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2023-05-01 | Hot deformation behavior of a high Al ferritic low-density steel (Fe-11wt.%Al-10wt.%Mn-1wt.%C) was investigated using hot compression tests up to a true strain of 0.69 at strain rates of 0.001-0.1 s −1 in a Gleeble thermomechanical simulator. When deformed at 900 °C the steel is ferritic and mostly dynamic recovery was observed. The samples hot compressed at 1000 and 1100 °C exhibited a dual phase microstructure (ferrite + austenite) and an appreciable amount of dynamic recrystallization (DRX) was observed in both the phases. There was a significant refinement in microstructure when the alloy was deformed in the intercritical region. The activation energy of dynamic recrystallization for the alloy was calculated to be 272.08 kJ mol −1 . The ferrite phase exhibited continuous dynamic recrystallization (CDRX) whereas the austenite exhibited discontinuous dynamic recrystallization (DDRX). A constitutive equation for predicting the flow stress values corresponding to a particular strain during hot deformation was derived using the basic Zener-Hollomon equation. Average absolute relative error (AARE) value of 6.2% and correlation coefficient (R) value of 0.97 were obtained indicating a high accuracy of the formulated constitutive relation. The DRX fractions were calculated from Johnson–Mehl–Avrami–Kolmogorov (JMAK) equation as well as grain orientation spread (GOS ≤ 1°) criterion. Fractions obtained for different deformation conditions by the two methods were compared. | Studies on Hot Deformation Behavior and Dynamic Recrystallization in a High Al Ferritic Low-Density Steel | 10.1007/s11665-022-07428-6 |
2023-05-01 | The paper presents a computational and analytical study of GTP-based cogeneration power plants, designed to produce electrical power using low-grade heat energy obtained from liquefied natural gas (LNG). Each energy system consists of three circuits. Results of thermodynamic calculations carried out for all circuits of the considered power plants are discussed, together with a comparison in terms of efficiency, power, and energy return coefficients, taking into account various working fluids and conditions at the boundaries of circuits. | Assessing the Efficiency of Circuit Solutions for LNG-Fueled GTP-Based Cogeneration Plants | 10.1007/s10556-023-01207-3 |
2023-05-01 | Abstract Experiments were carried out to study the stable attachment of an atmospheric pressured argon dc arc to the surface of pure, thoriated and lanthanated tungsten. Using spectroscopic methods electron temperatures and concentrations were obtained in the positive plasma column near the cathode. With a current of 200 A and a plasma gas flow rate of 1.5 g/s, the average values of temperatures were T e ~ 2.6 eV for pure tungsten, T e ~ 2 eV for thoriated and lanthanated tungesten, and concentrations n e ~ 10 17 cm –3 . In these experiments, the cathode with an insert of lanthanated tungsten (3100 K) had the lowest working surface temperature due to the lower effective work function, while for thoriated and pure tungsten surface temperatures were 3300 and 3800 K, respectively. It was found that at a current of 200 A, the tip of the pure tungsten cathode was in the liquid phase, in contrast to thoriated and lanthanated tungsten that remained in solid phase. | Research of the Binding of an Argon Arc to the Cathode in a DC Plasma Torch | 10.1134/S1063780X22601493 |
2023-05-01 | Dry sliding friction and wear test of Nb containing low carbon microalloyed steel was carried out at room temperature, and the effect of Nb on the wear behavior of the steel, as welll as the mechanism was studied. Scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) were employed to analyze the morphology and composition of the worn surface, and the structure evolution of the plastic deformation layer. The carbide content and type in the steel were analyzed by the electrolytic extraction device and X-ray diffraction (XRD). The experimental results demonstrate that the addition of 0.2% Nb can refine the grain and generate NbC to improve the wear resistance of the steel. By enhancing the load and speed of wear experiment, the wear mechanism of the test steel with 0.2% Nb changes from slight oxidation wear to severe adhesion wear and oxidation wear. Compared with the load, the increase in the rotation speed exerts a greater influence on the wear of the test steel. | Friction and wear behavior and mechanism of low carbon microalloyed steel containing Nb | 10.1007/s41230-023-2104-8 |
2023-05-01 | Recently, rapid progress has been made in the application of organic-inorganic halide perovskites in electronic devices, such as memristors and artificial synaptic devices. Organic-inorganic halide perovskite is considered as a promising candidate for the next generation of computing devices due to its ion migration property and advantages in manufacturing. In this work, a two-dimensional (2D)-3D organic-inorganic hybrid perovskite memristor was studied, using the stacking structure of indium tin oxide (ITO)/FA 1− y MA y PbI 3−x Cl x /(PEA) 2 PbI 4 /Au. The results show that this new type of memristor has novel resistance switching characteristics, such as scanning-rate-dependent current switching property, good current-voltage ( I–V ) curve repeatability, and ultralow energy consumption. A defect-modulated electron tunneling mechanism is demonstrated using the p-i-n junction model, and it is proven that the conductance state of the memristive device is determined by the defect concentration in the perovskite film near the electrode sides. In addition to the good memristive properties, this 2D-3D perovskite memristor can also function well as an artificial synapse, and its internal defect movement can faithfully simulate the inflow and extrusion of Ca 2+ in biological synapses. Moreover, this perovskite-based artificial synapse has ultra-low power consumption due to the switchable p-i-n structure in organic-inorganic halide perovskites. Our finding highlights the immense application potential of the 2D-3D perovskite memristor in the future neuromorphic computing system. 近年来, 有机-无机卤化物钙钛矿在忆阻器和人工突触器件等电子器件中的应用取得了快速进展. 由于其离子迁移特性和制造上的优势, 有机-无机卤化物钙钛矿有望成为下一代计算设备的候选材料. 本文采用ITO/FA1−yMAyPbI 3− x Cl x /(PEA) 2 PbI 4 /Au的叠层结构, 研究了2D-3D有机-无机杂化钙钛矿忆阻器. 结果表明, 这种新型忆阻器具有新颖的电阻开关特性, 如扫描速率相关的电流开关特性、良好的电流-电压曲线重复性和超低能耗. 利用p-i-n结模型证实了缺陷调制电子隧穿机制, 并证明了忆阻器件的电导状态由电极侧附近钙钛矿薄膜中的缺陷浓度决定. 除了良好的忆阻特性外, 这种2D-3D钙钛矿型忆阻器还可以很好地用作人工突触, 其内部缺陷运动可以真实地模拟生物突触中Ca 2+ 的流入和挤出. 此外, 由于有机-无机卤化物钙钛矿中的可切换p-i-n结构, 这种基于钙钛矿的人工突触具有超低功耗. 我们的发现展示了2D-3D钙钛矿忆阻器在未来神经形态计算系统中的巨大应用潜力. | 2D-3D perovskite memristor with low energy consumption and high stability for neural morphology calculation | 10.1007/s40843-022-2317-0 |
2023-05-01 | Vibrio natriegens has massive biotechnological potential owing to its fast growth rate. However, this bacterium rapidly loses its culturability during low-temperature preservation (LTP), the reason for which is still unknown. To reveal the metabolic responses of V. natriegens during LTP, we analyzed and compared the transcriptome before and after 8 days of preservation at 4 or 25 °C (room-temperature preservation (RTP)) in liquid culture medium. Most genes exhibited significant transcriptional responses to LTP. Using gene set enrichment analysis, we compared the transcriptional responses of different V. natriegens Gene Ontology (GO) sets during LTP or RTP. The enrichment of the GO set “SOS response” during LTP, but not RTP, indicated the occurrence of DNA damage during LTP. The GO set “respiratory electron transport chain” was suppressed during LTP and RTP. Although the GO set “response to oxidative stress” was not significantly altered, we observed an increase in reactive oxygen species (ROS) during LTP, suggesting a relationship between ROS and cold-induced loss of culturability (CILC) in V. natriegens . The faster loss of culturability and accumulation of ROS in 20 mL compared to 100 mL of liquid culture medium further suggested a relationship between CILC and oxygen availability. Furthermore, we showed that the deletion of Na + -translocating NADH-ubiquinone oxidoreductase, but not type-II NADH dehydrogenase, accelerated CILC and increased intracellular ROS levels in V. natriegens . These findings will help to understand the cause of CILC which may lead to improving the stability of V. natriegens at low temperatures. • V. natriegens transcriptome was analyzed before and after storage at 4 or 25 °C. • V. natriegens SOS response was induced by 4 °C storage. • Medium volume, NaCl concentration, and nqr deletion affect the CILC of V. natriegens. | Transcriptomic responses of the fast-growing bacterium Vibrio natriegens during cold-induced loss of culturability | 10.1007/s00253-023-12487-3 |
2023-05-01 | The paper presents the design of a device for the low-temperature separation of liquid media with two-stage freezing using frozen ice as a cold-accumulating mass for product pre-cooling. A method for calculating the dynamics of the water ice freezing on the inner cylindrical surface, represented by the working surface of the proposed device, is proposed. The efficiency values of single- and two-stage freezing devices are compared. | Evaluating the Performance of Low-Temperature Liquid Separation Devices with Two-Stage Refrigeration and Pre-Cooling | 10.1007/s10556-023-01218-0 |
2023-05-01 | In the present work, the response of composite hybrid laminates made of carbon and glass fibers in different stacking configurations was tested under low-velocity impact loads. Experimental drop impact tests were conducted on three different stacking sequences and three rising impact energy levels. The results from the tests were assumed for the development and validation of a numerical impact model reproducing for each stacking sequence and all the impact energy levels, the laminates impact response. The validated model investigated the occurred damage mechanisms, their distribution in the panel thickness and their extension on the plane of the laminate. Depending on the stacking sequence and the impact energy level, the energy absorption capacity was related to the dominant damage mechanism. The percentage contribution of interlaminar and intralaminar damages was presented and conclusions were drawn about the influence of stacking sequences on energy absorption and damage characteristics. | Design, Manufacturing, and Numerical Characterization of Hybrid Fiber Reinforced Polymer under Dynamic Loads | 10.1007/s11665-023-07926-1 |
2023-05-01 | Seasonal low-oxygen in marine ranching in the northern Yellow Sea has been one of the major environmental problems in coastal waters in recent years. Nitrogen (N) and phosphorus (P) are important nutrients, which are susceptible to the concentration of dissolved oxygen (DO). This article studied the effects of low-oxygen on nutrients represented by N and P fractions in marine ranching in the northern Yellow Sea. The results showed that there were significant layer differences in temperature and salinity during the low-oxygen period. In the seawater, the nutrient distribution in the death disaster zone of sea cucumbers and the non-disaster zone was similar, and DO had a strong positive correlation with dissolved inorganic nitrogen (DIN). In the sediment, significant regional differences existed in nutrient concentration, and the concentration of total phosphorus (TP) decreased significantly with the increase in DO content. The results showed that the sources and sinks of nitrogen and phosphorus nutrients were inconsistent in this zone, and migration and transformation of the existing form of nitrogen with the seasonal changes in the water environment was a main factor for N distribution. This study extended the understanding of the effects of seasonal low-oxygen on N and P. | Distribution of nitrogen (N) and phosphorus (P) in seasonal low-oxygen marine ranching in northern Yellow Sea, China | 10.1007/s11356-023-26932-3 |
2023-05-01 | Abstract The concept of plasma mass separation of substances in a configuration with a potential well implies the creation of specialized plasma sources that comply with a number of requirements. The following can be distinguished as the main ones: a high degree of ionization of the plasma flow, single ionization, the possibility of working with a complex mixture of oxides and metals as a working substance, high productivity rate (up to 1 kg/h), kinetic energy at the level of several tens of electron-volts. One possible application of this concept is the separation of spent nuclear fuel. The conversion of condensed matter into a low-temperature plasma flow and its further injection into the separation chamber is the initial stage of the concept and it largely determines the efficiency of the technological process. This paper presents the results of studies of the energy distribution of lead ions in the plasma jet of a plasma source created on the basis of a non-self-sustained arc discharge with a hot cathode in a magnetic field. The influence of this distribution on the separation process was analyzed. | Transformation of Condensed Matter into a Low-Temperature Plasma Flow for Problems of Plasma Mass Separation with a Potential Well | 10.1134/S1063780X22601754 |
2023-05-01 | Objectives The aim of the study was to determine the association between occupational ambient cold exposure and neck–shoulder pain (NSP), low back pain (LBP), and radiating LBP. Methods The study cohort comprised of 3,843 working subjects in northern Sweden who answered a baseline (spring 2015) and a follow-up questionnaire (spring 2021). NSP, LBP, and radiating LBP were assessed in both surveys. Occupational cold exposure was assessed at baseline, on a whole number numerical rating scale (NRS) and categorized in quartiles. Binary logistic regression determined the association between cold exposure at baseline and incident NSP, LBP, and radiating LBP, adjusted for age, gender, body mass index, smoking, mental stress, and physical workload. Results There were statistically significant associations between high occupational ambient cold exposure (NRS 5–7 and NRS 8–10) and NSP (1.59; 95% CI 1.08–2.33 and OR 1.50; 95% CI 1.03–2.19); NRS 8–10 and LBP (OR 1.61; 95% CI 1.13–2.29); and NRS 5–7 and radiating LBP (OR 1.87; 95% CI 1.12–3.16). Gender-stratified analyses showed statistically significant associations between high occupational ambient cold exposure (NRS 5–7 and NRS 8–10) and NSP (OR 1.97; 95% CI 1.07–3.61 and OR 1.97; 95% CI 1.06–3.67) for men and between NRS 8–10 and LBP (OR 1.82; 95% CI 1.14–2.91) and NRS 5–7 and radiating LBP (OR 2.20; 95% CI 1.15–4.24) for women. Conclusions Occupational ambient cold exposure was associated with NSP, LBP, and radiating LBP, and should be recognised as a possible occupational risk factor. | The association between cold exposure and musculoskeletal disorders: a prospective population-based study | 10.1007/s00420-022-01949-2 |
2023-05-01 | Abstract Macro- and fractographic studies of fractures of CTOD specimens after fatigue testing of essential steel rolled products with a thickness of 82 mm for fixed offshore structures of the S420MLO quality category, produced using the technology of thermomechanical processing with accelerated cooling, are presented. Fracture nature and the mechanisms of fatigue crack propagation at test temperatures of minus 10 and minus 30°C were studied. The potential reasons for the formation of a “secondary” fatigue crack propagation front and its potentially negative impact on the final test results are described. Research results and testing were used in passing, with a positive result of certification tests of rolled products of quality categories S355MLO and S420MLO with a thickness of up to 82 mm in accordance with the requirements of EN10225-1:2019 and NORSOK M-120. | Fractographic Studies of Destruction Nature of Plate Steel S420MLO After Fatigue Tests CTOD | 10.3103/S0967091223050054 |
2023-05-01 | The study investigates the mechanism of teleconnection between the variability of sea ice extent (SIE) in the Indian Ocean sector of the Southern Ocean and the variability of Indian summer monsoon rainfall. We utilized reanalysis, satellite, in-situ observation data, and model output from the coupled model intercomparison project phase 5 (CMIP5) from 1979 to 2013. The empirical orthogonal function (EOF) and correlation analysis show that the first and third modes of principal component (PC1 and PC3) of SIE in the Indian Ocean sector during April–May–June (AMJ) are significantly correlated with the second mode of principal component (PC2) of Indian summer monsoon rainfall. The reanalysis data revealed that the changes in the SIE in the Indian Ocean sector excite meridional wave train responses along the Indian Ocean for both principal component modes. Positive (negative) SIE anomalies based on first and third EOFs (EOF1 and EOF3), contribute to the strengthening (weakening) of the Polar, Ferrel, and Hadley cells, inducing stronger (weaker) convective activity over the Indian latitudes. The stronger (weaker) convective activity over the Indian region leads to more (less) rainfall over the region during high (low) ice phase years. Furthermore, a stronger (weaker) polar jet during the high (low) ice phase is also noted. The selected CMIP5 models captured certain atmospheric teleconnection features found in the reanalysis. During AMJ, the SIE simulated by the NorESM1-M model was significantly positively correlated with Indian summer monsoon rainfall, whereas the IPSL-CM54-LR model showed a negative correlation. | The mechanism linking the variability of the Antarctic sea ice extent in the Indian Ocean sector to Indian summer monsoon rainfall | 10.1007/s00382-022-06466-z |
2023-05-01 | A major source of anthropogenic polycyclic aromatic hydrocarbon (PAH) inputs into marine environments are diffuse emissions which result in low PAH concentrations in the ocean water, posing a potential threat for the affected ecosystems. However, the remediation of low-dosage PAH contaminations through microbial processes remains largely unknown. Here, we developed a process-based numerical model to simulate batch cultures receiving repeated low-dosage naphthalene pulses compared to the conventionally used one-time high-dosage. Pulsing frequency as well as dosage concentration had a large impact on the degradation efficiency. After 10 days, 99.7%, 97.2%, 86.6%, or 83.5% of the 145 mg L −1 naphthalene was degraded when given as a one-time high-dosage or in 2, 5, or 10 repeated low-concentration dosages equally spaced throughout the experiment, respectively. If the simulation was altered, giving the system that received 10 pulses time to recover to 99.7%, pulsing patterns affected the degradation of naphthalene. When pulsing 10 days at once per day, naphthalene accumulated following each pulse and if the degradation was allowed to continue until the recovered state was reached, the incubation time was prolonged to 17 days with a generation time of 3.81 days. If a full recovery was conditional before the next pulse was added, the scenario elongated to 55 days and generation time increased to 14.15 days. This indicates that dissolution kinetics dominate biodegradation kinetics, and the biomass concentration of PAH-degrading bacteria alone is not a sufficient indicator for quantifying active biodegradation. Applying those findings to the environment, a one-time input of a high dosage is potentially degraded faster than repeated low-dosage PAH pollution and repeated low-dosage input could lead to PAH accumulation in vulnerable pristine environments. Further research on the overlooked field of chronic low-dosage PAH contamination is necessary. | Dosage concentration and pulsing frequency affect the degradation efficiency in simulated bacterial polycyclic aromatic hydrocarbon-degrading cultures | 10.1007/s11356-023-26546-9 |
2023-05-01 | Long-term bioelectric potential recording requires highly reliable wearable dry electrodes. Laser-induced graphene (LIG) dry electrodes on polyimide (PI) films are difficult to conform to the skin due to the non-stretchability and low flexibility of PI films. As a result, high interface impedance and motion artifacts can occur during body movements. Transferring LIG to flexible substrates such as polydimethylsiloxane (PDMS) and Ecoflex allows for stretchability and flexibility. However, the transfer process produces a significant loss of conductivity destroying the structural function and electron conduction properties of the LIG. We found robust physical and chemical bonding effects between LIG and styrene-ethylene-butylene-styrene (SEBS) thermoplastic elastomer substrates and proposed a simple and robust low-conductivity loss transfer technique. Successfully embedded LIG onto SEBS to obtain high stretchability, high flexibility, and low conductivity losses. Electrophoretic deposition (EPD) of poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid (PEDOT:PSS) on LIG forms an ultrathin polymer conductive coating. The deposition thickness of the conductive polymer is adjusted by controlling the EPD deposition time to achieve optimal conductivity and chemical stability. SEBS/LIG/PEDOT:PSS (SLPP) dry electrodes have high conductivity (114 Ω/Sq), stretchability (300%) and reliability (30% stretch, 15,000 cycles), and low electrode-skin impedance (14.39 kΩ, 10 Hz). The detected biopotential signal has a high signal-to-noise ratio (SNR) of 35.78 dB. Finally, the feasibility of SLPP dry electrodes for long-term biopotential monitoring and biopotential-based human-machine interface control of household appliances was verified. | Highly conductive, stretchable, durable, skin-conformal dry electrodes based on thermoplastic elastomer-embedded 3D porous graphene for multifunctional wearable bioelectronics | 10.1007/s12274-023-5429-5 |
2023-05-01 | Designing highly active and thermally stable electrodes is crucial for realizing low-temperature solid oxide fuel cells (LT-SOFCs) with excellent performance. In this study, we fabricated an yttria-doped ceria (YDC) shell layer by atomic layer deposition (ALD) over a Pt cathode by controlling the doping concentration of yttria in YDC film. The exchange current density was enhanced by a factor of five when the ALD YDC shell layer was deposited onto the cathode surface compared to the bare Pt cathode, resulting in an 80% decrease in the activation resistance of the 19 mol%-doped ALD YDC-overcoated Pt cathode compared to that of the bare Pt cathode. Furthermore, the thermal stability was enhanced in low-to-medium-doped (7–19 mol%) ALD YDC-coated Pt cathodes, whereas the highly doped (31 mol%) cathode showed a relatively marginal improvement in stability. | Nanometer Yttria-doped Ceria Shell by Atomic Layer Deposition over Porous Pt for Improved Oxygen Reduction Reactions | 10.1007/s40684-023-00506-7 |
2023-05-01 | Urbanisation can cause a variety of environmental and health issues, which has prompted experts to evaluate degraded areas and develop management strategies aimed at promoting urban sustainability and reducing carbon emissions. In low-carbon cities, sustainable urban areas have low carbon emission and prioritised carbon reduction by implementing sustainable transportation, green infrastructure, and energy-efficient buildings. On the other hand, unsustainable urban areas tend to lack these priorities and rely heavily on non-renewable energy sources and have high carbon emission. Therefore, this study aims to identify the most sustainable and unsustainable regions in the Abha-Khamis Mushayet Twin City region of Saudi Arabia in respect to urbanisation and carbon emission during the period between 1990 and 2020. To do so, we used Landsat datasets to create land use land cover (LULC) maps and then calculated carbon storage, emission, and absorption using InVest software. Additionally, the study examined micro-climatic conditions by calculating the urban heat island (UHI) effect, which allowed determining sustainable and unsustainable regions by comparing the UHI model and carbon similarity and mismatch model using coupling coordination degree model ( CCDM ). The study found that during the last three decades, the LULC pattern of the region underwent significant alterations, resulting in a substantial decline in carbon storage from 710,425 Mg C/hm 2 in 1990 to approximately 527,012.9 Mg C/hm 2 in 2020. Conversely, carbon emissions were observed to be very high in areas with high built-up density, with emission levels exceeding 20 tons per annum. Whilst the areas of excess carbon have decreased significantly, the areas of excess carbon emission have increased over time, resulting in the UHI effect due to high greenhouse gases. By comparing the UHI and carbon similarity and mismatch model, the researchers found that over 280 km 2 of the study area is unsustainable and has increased since 1990. In contrast, only about 410 km 2 of the study area is currently sustainable. To promote sustainability, the study recommends several strategies such as carbon capture, utilisation, and storage; green infrastructure; and the use of renewable energy to manage carbon emissions. | Mapping and evaluating sustainable and unsustainable urban areas for ecological management towards achieving low-carbon city: an empirical study of Asir Region, Saudi Arabia | 10.1007/s11356-023-27129-4 |
2023-05-01 | The effect of the micro-structure surface on the passive compression performance of the intake system of an air-breathing ion engine (ABIE) system is proposed and analysed. The scattering distributions of the thermal Ar beam pulses at the microstructure surface were measured experimentally. The scattering process at the microstructure surface demonstrated anisotropic nature at a grazing angle of incidence; however, it demonstrated a complex scattering pattern due to the multiple bounce effect at the facet surface, despite each scattering pattern being similar to that on the flat surface. The DSMC calculation at an altitude of 250 km was also performed using the simple scattering model, which is based on the experimental results of scattering distribution and recent ABIE design. The computational results indicate that the compression performance of the microstructure intake is higher than that of the diffusive and specular flat intakes. | Anisotropic molecular scattering at microstructured surface for rarefied gas compression inside air breathing ion engine | 10.1007/s12567-022-00430-7 |
2023-05-01 | Lead (Pb) is a known environmental risk factor in the etiology of Alzheimer’s disease (AD). The existing reports suggest that Pb exposure increases beta-amyloid (Aβ) levels in brain tissues and cerebrospinal fluid (CSF) and facilitates the formation of amyloid plaques, which is a pathological hallmark for AD. Pb exposure has long been associated with cerebral vasculature injury. Yet it remained unclear if Pb exposure caused excessive Ab buildup in cerebral vasculature, which may damage the blood–brain barrier and cause abnormal Ab accumulation. This study was designed to investigate the impact of chronic Pb exposure on Aβ accumulation in cerebral capillary and the expression of low-density lipoprotein receptor protein-1 (LRP1), a critical Aβ transporter, in brain capillary and parenchyma. Sprague–Dawley rats received daily oral gavage at doses of 0, 14 (low-dose), and 27 (high-dose) mg Pb/kg as Pb acetate, 5 d/wk, for 4 or 8 wks. At the end of Pb exposure, a solution containing Aβ 40 was infused into the brain via the cannulated internal carotid artery. Data by ELISA showed a strikingly high affinity of Ab to cerebral vasculature, which was approximately 7–14 times higher than that to the parenchymal fractions collected from control brains. Pb exposure further aggravated the Aβ accumulation in cerebral vasculature in a dose-dependent manner. Western blot analyses revealed that Pb exposure decreased LRP1 expression in cortical capillaries and hippocampal parenchyma. Immunohistochemistry (IHC) studies further revealed a disrupted distribution of LRP1 alongside hippocampal vasculature accompanied with a decreased expression in hippocampal neurons by Pb exposure. Taken together, the current study demonstrated that the cerebral vasculature naturally possessed a high affinity to Aβ present in circulating blood. Pb exposure significantly increased Aβ accumulation in cerebral vasculature; such an increased Aβ accumulation was due partly to the diminished expression of LRP1 in response to Pb in tested brain regions. Perceivably, Pb-facilitated Ab aggravation in cerebral vasculature may contribute to Pb-associated amyloid alterations. 1. Affinity of Aβ 40 to cerebral vasculature was exceptionally high. 2. Pb exposure exacerbated Aβ 40 accumulation in cerebral vasculature. 3. LRP1 expression was disrupted by Pb in brain parenchyma and vasculature. | High affinity of β-amyloid proteins to cerebral capillaries: implications in chronic lead exposure-induced neurotoxicity in rats | 10.1186/s12987-023-00432-5 |
2023-05-01 | Background The human population living in high level natural radiation areas (HLNRAs) of Kerala coast provide unique opportunities to study the biological effects of low dose and low dose rate ionizing radiation below 100 mGy. The level of radiation in this area varies from < 1.0 to 45 mGy/year. The areas with ≤ 1.50 mGy/year are considered as normal level natural radiation areas (NLNRA) and > 1.50 mGy/year, as high level natural radiation areas (HLNRA). The present study evaluated dose response relationship between DNA double strand breaks (DSBs) and background radiation dose in individuals residing in Kerala coast. Venous blood samples were collected from 200 individuals belonging to NLNRA (n = 50) and four dose groups of HLNRA; 1.51-5.0 mGy/year (n = 50), 5.01-10.0 mGy/year (n = 30), 10.01-15.0 mGy/year (n = 33), > 15.0 mGy/year (n = 37) with written informed consent. The mean dose of NLNRA and four HLNRA dose groups studied are 1.21 ± 0.21 (range: 0.57–1.49), 3.02 ± 0.95 (range: 1.57–4.93), 7.43 ± 1.48 (range: 5.01–9.75), 12.22 ± 1.47 (range: 10.21–14.99), 21.64 ± 6.28 (range: 15.26–39.88) mGy/year, respectively. DNA DSBs were quantified using γH2AX as a marker, where foci were counted per cell using fluorescence microscopy. Results Our results revealed that the frequency of γH2AX foci per cell was 0.090 ± 0.051 and 0.096 ± 0.051, respectively in NLNRA and HLNRA individuals, which were not significantly different (t 198 = 0.33; P = 0.739). The frequency of γH2AX foci was observed to be 0.090 ± 0.051, 0.096 ± 0.051, 0.076 ± 0.036, 0.087 ± 0.042, 0.108 ± 0.046 per cell, respectively in different dose groups of ≤ 1.50, 1.51-5.0, 5.01-10.0, 10.01-15.0, > 15.0mGy/year (ANOVA, F 4,195 = 2.18, P = 0.072) and suggested non-linearity in dose response. The frequency of γH2AX foci was observed to be 0.098 ± 0.042, 0.078 ± 0.037, 0.084 ± 0.042, 0.099 ± 0.058, 0.097 ± 0.06 and 0.114 ± 0.033 per cell in the age groups of ≤ 29, 30–34, 35–39, 40–44, 45–49 and ≥ 50 years, respectively (ANOVA, F 5,194 = 2.17, P = 0.059), which suggested marginal influence of age on the baseline of DSBs. Personal habits such as smoking (No v/s Yes: 0.092 ± 0.047 v/s 0.093 ± 0.048, t 198 = 0.13; P = 0.895) and drinking alcohol (No v/s Yes: 0.096 ± 0.052 v/s 0.091 ± 0.045, t 198 = 0.62; P = 0.538) did not show any influence on DSBs in the population. Conclusion The present study did not show any increase in DSBs in different dose groups of HLNRA compared to NLNRA, however, it suggested a non-linear dose response between DNA DSBs and chronic low dose radiation. | Non-linear dose response of DNA double strand breaks in response to chronic low dose radiation in individuals from high level natural radiation areas of Kerala coast | 10.1186/s41021-023-00273-6 |
2023-05-01 | We use an ocean general circulation model and its adjoint to analyze the causal chain linking sea surface buoyancy anomalies in the Labrador Sea to variability in the deep branch of the Atlantic meridional overturning circulation (AMOC) on inter-annual timescales. Our study highlights the importance of the North Atlantic Current (NAC) for the north-to-south connectivity in the AMOC and for the meridional transport of Lower North Atlantic Deep Water (LNADW). We identify two mechanisms that allow the Labrador Sea to impact velocities in the LNADW layer. The first mechanism involves a passive advection of surface buoyancy anomalies from the Labrador Sea towards the eastern subpolar gyre by the background NAC. The second mechanism plays a dominant role and involves a dynamical response of the NAC to surface density anomalies originating in the Labrador Sea; the NAC adjustment modifies the northward transport of salt and heat and exerts a strong positive feedback, amplifying the upper ocean buoyancy anomalies. The two mechanisms spin up/down the subpolar gyre on a timescale of years, while boundary trapped waves rapidly communicate this signal to the subtropics and trigger an adjustment of LNADW transport on a timescale of months. The NAC and the eastern subpolar gyre play an essential role in both mechanisms linking the Labrador Sea with LNADW transport variability and the subtropical AMOC. We thus reconcile two apparently contradictory paradigms about AMOC connectivity: (1) Labrador Sea buoyancy anomalies drive AMOC variability; (2) water mass transformation is largest in the eastern subpolar gyre. | Fast mechanisms linking the Labrador Sea with subtropical Atlantic overturning | 10.1007/s00382-022-06459-y |
2023-05-01 | Modern developments of biomedical applications demand a better understanding of mechanical behaviour of soft biological tissues. As human soft tissues demonstrate a significant structural and functional diversity, characterisation of their mechanical behaviour still remains a challenge. Limitations related with implementation of mechanical experiments on human participants lead to a use of finite-element models for analysis of mechanical responses of soft tissues to different loads. This study focuses on parameters of numerical simulation considered for modelling of indentation of a human lower limb. Assessment of the effect of boundary conditions on the model size shows that at a ratio of its length to the tissue’s thickness of 1.7 for the 3D model this effect vanishes. The numerical results obtained with models employing various sets of mechanical parameters of the first-order Ogden scheme were compared with original experimental data. Furthermore, high sensitivity of the resulting reaction forces to the indenting direction is demonstrated for cases of both linear and angular misalignments of the indenter. Finally, the effect of changes in material parameters and their domain on their contribution to the reaction forces is discussed with the aim to improve our understanding of mechanical behaviour of soft tissues based on numerical methods. The undertaken research with its results on minimal requirements for finite-element models of indentation of soft tissues can support inverse analysis of their mechanical properties and underpin orthopaedic and medical procedures. | Modelling indentation of human lower-limb soft tissue: simulation parameters and their effects | 10.1007/s00161-020-00933-w |
2023-05-01 | A generation of microplastics caused by improper disposal of disposable masks has become a non-negligible environmental concern. In order to investigate the degradation mechanisms of masks and the release of microplastics under different environmental conditions, the masks are placed in 4 common environments. After 30 days of weathering, the total amount and release kinetics of microplastics released from different layers of the mask were studied. The chemical and mechanical properties of the mask were also discussed. The results showed that the mask released 25141±3543 particles/mask into the soil, which is much more than the sea and river water. The release kinetics of microplastics fit the Elovich model better. All samples correspond to the release rate of microplastics from fast to slow. Experiments show that the middle layer of the mask is released more than the other layers, and the amount of release was highest in the soil. And the tensile capacity of the mask is negatively correlated with its ability to release microplastics in the following order, which are soil > seawater > river > air > new masks. In addition, during the weathering process, the C-C/C-H bond of the mask was broken. | Different weathering conditions affect the release of microplastics by masks | 10.1007/s11356-023-27116-9 |
2023-05-01 | Within Salmonidae, spawning and rearing in brackish water is rare; however, brackish-water resident lake trout ( Salvelinus namaycush ) have recently been documented in the Arctic. Additionally, early rearing in brackish-water environments increased the fish’s ability to ionoregulate in elevated salinities. Here, we examined the impact of a freshwater (FWR, 0 ppt) or brackish-water (BWR, 5 ppt) rearing environment on salinity preference in lake trout using a dynamic choice experiment. We observed significant differences in salinity preference between our treatments suggesting the importance of early environment in shaping salinity preference. Contrary to our predictions, FWR lake trout selected higher salinity (17.3 ppt) compared to BWR fish (4.8 ppt). Four of the seven FWR fish had preferred salinities near 30 ppt, which is considered physiologically challenging and potentially lethal for lake trout based on direct transfer experiments. Thus, heightened FWR salinity preference might not be a true preference but rather due to a reduced ability to sense differences in salinity, and a result of chance as mean preferred salinity was near half that of the upper and lower thresholds, and variance was larger. Selection of lower salinity by BWR fish suggests that the ability to sense and select different salinities is present in lake trout as a species and appears to be linked to difference in early rearing at elevated salinities. | A salt on your senses: influences of rearing environment on salinity preference and sensing in lake trout Salvelinus namaycush | 10.1007/s10641-022-01286-w |
2023-05-01 | For manufacturing HC340LA cold-rolled steel annealed in bell-type furnaces from two melt steel of different compositions using Nb or Ti microalloying, metal samples were studied from nine experimental batches of hot-rolled semi-finished stocks. Based on the results, the efficiency of the developed principles for improving the existing technology to enhance the properties and quality of steel is substantiated while reducing production costs. | Justification of the Production Technology Efficiency for Low-Alloy Steels with Improved Properties and Quality at Low-Cost. Part 1. Hot-Rolled Products | 10.1007/s11015-023-01496-2 |
2023-05-01 | Abstract The performance of polyalkyl acrylate additives of various compositions in low-temperature dewaxing of 11 oil fractions differing in the viscosity and content of waxes, aromatic hydrocarbons, and resins was studied. The dewaxing was performed in a methyl ethyl ketone–toluene mixed solvent. For polyalkyl acrylate with pendant C 16–10 alkyl chains, the raffinates can be subdivided into three groups with respect to an increase in the yield of dewaxed oils (relative to the process without additives): increase by 12–13, 5–8, and 3–4%. In most cases, introduction into such polymer of 5–30% polar groups (amino ester, amino amide, amide, oligoethylene glycol) allowed the oil yield to be additionally increased. | Performance of Polyalkyl Acrylate Additives of Various Compositions in Low-Temperature Dewaxing of Oil Raffinates | 10.1134/S0965544123030155 |
2023-05-01 | Low-head dams are becoming a ubiquitous feature of the landscape of headwater streams. The ecological effects of low-head dams have long been studied; however, most studies have ignored the invasion of native-invasive species commonly occurring in large streams. Based on fish data from 25 first-order streams within an important tributary of the Yangtze River, we investigated whether and how low-head dams facilitate the invasion of native-invasive fish to headwater streams in regions where native fish species are completely dominant. We found that the ratio of native-invasive species (Ratio) was significantly higher in impoundments than in free-flowing segments, suggesting that low-head dams facilitate the invasion of native-invasive fish. We demonstrated that the niche and dispersal processes affected the seasonal variation in Ratio differently. In addition, changes in the Ratio using abundance data were significantly related to landscape conditions and dam size in the dry season and only to landscape conditions in the wet season, suggesting that the latter greatly underestimated the blocking effect of low-head dams on fish dispersal. In conclusion, our study demonstrated that increasing anthropogenic landscape disturbances in catchments where low-head dams were located exacerbated the invasion of native-invasive species are commonly found in large streams. | Low-head dams facilitate the native invasion of downstream fishes to subtropical headwater streams, China | 10.1007/s10750-023-05200-y |
2023-05-01 | The creep characteristics of coal pillars left over from old mining directly affect the long-term stability of underground engineering. To study the creep characteristics and long-term stability of the No. 3 anthracite pillar in Qinshui Coal Field, Shanxi Province, China, conventional triaxial compression and triaxial creep tests were conducted under four low confining pressures (0.5, 1.0, 1.5 and 2.0 MPa), and the creep laws of the anthracite samples under different confining pressures were explored. Moreover, based on the test data, a nonlinear viscoelastic-plastic creep model was established which could better describe each creep stage. The test results show that: 1) when the axial stress is higher than the yield stress, the creep of anthracite undergoes three stages: initial creep, steady creep, and accelerated creep; 2) the instantaneous elastic strain of anthracite increases linearly with the axial stress level, and the smaller the confining pressure was, the faster the instantaneous elastic strain increased; 3) Compared with the instantaneous strength, the long-term strength of anthracite decreased by approximately 20%. The creep properties reduced the shear strength of anthracite, and compared with the short-term shear strength, the internal friction angle and cohesion decreased by 8% and 14%, respectively. 旧采遗留煤柱的蠕变特性直接影响井下工程的长期稳定性, 小煤柱边界及内部弹性核区的应力环境一般为低围压三向应力状态。为了研究山西沁水煤田3#无烟煤柱的蠕变特性及长期稳定性, 进行了4 种低围压(0.5、1.0、1.5 和2.0 MPa)状态的常规三轴压缩和三轴蠕变试验, 探索了不同围压条件下无烟煤的蠕变规律, 并基于试验数据建立了能较好地描述各蠕变阶段的非线性黏弹塑性蠕变模型。试验研究结果表明:1)轴向应力大于屈服应力时, 无烟煤的蠕变经历三个阶段:即初始蠕变、稳定蠕变和加速蠕变阶段;2)无烟煤试样的瞬时弹性应变与轴向应力水平大致呈线性增长关系, 且围压越小, 其瞬时弹性应变随轴向应力水平的增长速率越快;3)与瞬时强度相比, 无烟煤的长期强度降低20%;蠕变特性降低了无烟煤的强度参数, 与短期抗剪强度相比, 其内摩擦角和内聚力分别降低了8%和14%。 | Experimental study on triaxial creep characteristics of the anthracite coal under low confining pressure | 10.1007/s11771-023-5317-5 |
2023-05-01 | Surface waves in the Arctic Seas are jointly analyzed using satellite altimeter observations, classical fetch and duration laws of wave development, and a two-dimensional parametric wave model. A simplified scenario is first considered for the wave development under known physical fetch conditions during cold air outbreak events. Wave developments are found to agree well with the fetch laws, given known wave fetch and fetch-averaged wind speed, for significant wave heights (SWHs) less than 4–6 m and wind speeds below 20 m s −1 . Wind wave conditions remarkably change for moving storms, associated with rapidly evolving polar lows (PLs). For such conditions, wind-generated waves exhibit properties similar to those encountered during tropical cyclones (TCs), reaching very large SWHs (8–12 m) and long wavelengths (up to 350 m). Still, wave parametrizations based on the extended fetch concept, previously developed for TC conditions, cannot be directly applied to PL cases due to their inherent marked space–time non-stationarity. Instead, an extended duration concept for wave development under PLs is suggested. Extended duration laws provide first-guess wave parameters, based on characteristic wind speed, translation velocity, spatial scale, and duration of a PL. A 2D parametric wave model, previously developed for TC conditions, is then applied to simulate waves generated during cold air outbreaks and PLs. Comparisons with altimeter measurements are favourable making it possible to consider this simple modelling tool for fast estimates and predictions of waves generated under highly variable Arctic wind conditions. | On Surface Waves in Arctic Seas | 10.1007/s10546-022-00768-9 |
2023-05-01 | The tuning of the structural batteries for various applications of transportation is an ambitious target. The pollutant emission and mostly the process for battery recycling and recovery are peculiar aspects to consider for new designs. The goal is to reduce the weight. In this frame, taking into account that the traditional battery packs do not contribute to the structural performance, it is worth to underline the solution of the structural batteries allows to increase the mechanical properties as they are integrated into the primary structure. The paper establishes the response of a composite structural battery model subjected to low-velocity impact tests. The process used to manufacture the structural battery model is described, and the experimental activities are performed by a customized drop tower and finally replicated numerically by explicit code to enhance the comprehension of the structural dynamics. Differences with respect to a carbon fiber laminate are highlighted both for the force released at the impact and dart displacement, for the same levels of energy. | Impact Response of a Composite Structural Battery in Low-Velocity Tests | 10.1007/s11665-023-07979-2 |
2023-05-01 | Two-dimensional metal-organic frameworks (2D MOFs), as a new type of 2D materials, have been widely applied in various applications because of their unique structures and exposed active sites. Herein, we reported two low-cost 2D MOFs constructed by a raw chemical succinic acid (SA), M-SA (M = Ni or Co), which served as efficient photocatalysts for the reduction of CO 2 to CO. Taking advantage of the thinness and open metal sites, the ultrathin Ni-SA nanosheets (ca. 3.6 nm) exhibited excellent CO production of 6.96(7) mmol·g −1 h −1 and CO selectivity of 96.6%. Photoelectrochemical tests and theoretical calculations further confirmed the higher charge transfer efficiency and unsaturated metal sites for promoting photocatalytic performances. More importantly, Ni-SA can also be synthesized in large-scale by an energy-saving method under room temperature, strongly suggesting its promising future and potential for practical applications. | Large-scale synthesis of low-cost 2D metal-organic frameworks for highly selective photocatalytic CO2 reduction | 10.1007/s12274-023-5405-8 |
2023-05-01 | Metal alloys have been widely applied for heterogeneous catalysis, especially alkane dehydrogenation. However, the catalysts always suffer from sintering and coke deposition due to the rigorous reaction conditions. Herein, we described an original approach to prepare a catalyst where highly dispersed Pt clusters alloying with copper were encapsulated in silicalite-1 (S-1) zeolite for propane dehydrogenation (PDH). The introduction of Cu species significantly enhances the catalytic activity and prolongs the lifetime of the catalyst. 0.1Pt0.4CuK@S-1 exhibits a propane conversion of 24.8% with 98.2% selectivity of propene, and the specific activity of propylene formation is up to 32 mol·g Pt −1 ·h −1 at 500 °C. No obvious deactivation is observed even after 73 h on stream, affording an extremely low deactivation constant of 0.00032 h −1 . The excellent activity and stability are ascribed to the confinement of zeolites and the stabilization of Cu species for Pt clusters. | Enhanced performance for propane dehydrogenation through Pt clusters alloying with copper in zeolite | 10.1007/s12274-022-5317-z |
2023-05-01 | The IANOS Medicane was one of the most severe storms that have formed in the Mediterranean Sea with Category 2 Hurricane characteristics. The storm induced a significant increase in sea-level elevation along its pathway and caused storm surges at the central Ionian Sea with consequent impacts on coastal regions of the Ionian Islands and western Greece. An integrated approach, based on hydrodynamic ocean simulations, coupled to meteorological and coastal flooding simulations, is used in combination with field and satellite observations to analyze the marine weather conditions, the storm surge characteristics, and the coastal inundation characteristics due to the impact of IANOS Medicane in September 2020. The evolution of the Medicane and the respective storm surge in the ocean have been successfully recorded by the met-ocean simulations, part of an active public-access operational forecast system. Both wind and atmospheric pressure patterns affected the storm surge variability over the Ionian Sea. The direct intrusion of the Medicane from the central Mediterranean Sea toward the Ionian Sea formed storm surges over several coastal areas, even before the storm’s landfall, due to the accompanying onshore currents. Storm surges in the order of 30 cm generated extensive flooding over lowland coastal areas, as confirmed by both satellite (Normalized Difference Water Index, NDWI) and numerical (coastal inundation modeling) data. Satellite-derived and simulated estimations showed that, in specific coastal regions, the run-up of seawater extended up to 200 m inland, depending on the hydraulic connectivity between the lowland areas, which determined the inundation extents during the storm surge. | Storm surges and coastal inundation during extreme events in the Mediterranean Sea: the IANOS Medicane | 10.1007/s11069-023-05890-6 |
2023-05-01 | Laser cladding technology is usually employed to produce high-entropy alloy coatings. However, the thickness of coatings is normally up to a millimeter scale, which increased the consumption of laser energy and materials. In this work, a micron-scale coating of CrMnFeCoNi high-entropy alloy on Al alloy by using low-power laser cladding was proposed. The influences of heat input on the geometric parameters and element distribution of coating were studied in detail. The results showed that the effects of heat input on the depth, width and dilution ratio of coating were obvious. The greater the heat input, the greater the uniformity in the element distribution of coating. When the heat input of 2 J/mm was used, the element distribution in the coating was uniform. The above results feasibility confirmed low-power laser cladding of micron-scale coating of high-entropy alloy on aluminum alloy. | Influences of Heat Input on the Geometric Parameters and Element Distribution of CrMnFeCoNi High-Entropy Alloy Coating on Aluminum Alloy Using Laser Cladding | 10.1007/s12666-022-02825-w |
2023-05-01 | The major challenge in the field of water quality monitoring is the presence of a large number of parameters and the difficulty related to their online measurement. Some variables can be measured continuously with low-cost sensors, however, there are other variables requiring specific and expensive laboratory analyses due to the lack of dedicated sensors. Soft sensors are an efficient and economical way to solve such problems. However, conventional soft sensors are subject to several external factors that may affect the robustness of the sensor, the most important of which is the noise generated by the measurement process. In this paper, a calcium (Ca) soft sensor is developed with lower costs and more robustness with respect to noise. For this purpose, four machine learning techniques integrated with an infinite impulse response (IIR) digital low-pass filter (LPF) are used as innovative models to address the above problems. In this work, Support Vector Regression (SVR), Extreme Learning Machine (ELM), Elman Recurrent Neural Network (ERNN), and Multilayer perceptron (MLP) models are used to develop the soft sensor. Moreover, Principal Component Analysis (PCA) technique is used to choose the variables that have the greatest impact on the soft sensor. The results showed that the developed models outperform the traditional soft sensors. Furthermore, the IIR-SVR hybrid model gives the best performance with root-mean-squared error ( RMSE ) = 1.595 mg/L, mean absolute error ( MAE ) = 1.194 mg/L, mean square error ( MSE ) = 2.544 mg/L, root relative squared error ( RRSE ) = 24.34%, and correlation coefficient ( R 2 ) = 0.941. | Calcium Soft Sensor Based on the Combination of Support Vector Regression and 1-D Digital Filter for Water Quality Monitoring | 10.1007/s13369-022-07263-w |
2023-05-01 | Wireless underground sensor networks (WUSNs) enable large-scale agricultural monitoring for improving farming efficiency and reducing pollution. A WUSN system based on the long range wide area network (LoRaWAN) standard is proposed. A novel LoRaWAN-based simulator is developed to model wireless signal attenuation and path loss in an underground environment by incorporating the Peplinski and modified Friis models. The simulator incorporates the full network stack of the LoRa physical and MAC layers. Simulation results show LoRaWAN-based WUSNs (with a node burial depth of 50 cm) can maintain network connectivity with a range of over several kilometres. The simulation results also show the regional duty cycle restriction significantly reduces network scalability due to acknowledgements from end-devices. For agricultural applications where such frequent acknowledgements are not required, the results show a LoRaWAN WUSN is scalable. A field experiment to evaluate the accuracy of the theoretical path loss model was conducted and results were found to agree with the simulations. | Long range wide area network for agricultural wireless underground sensor networks | 10.1007/s12652-020-02137-1 |
2023-05-01 | To evaluate the relationships between maternal particulate matter exposure and offspring birth weight. Studies were categorized into three subgroups: term low birth weight (TLBW) among full-term births and all births (regardless of gestational age) and low birth weight (LBW) among all births, based on the search results of MEDLINE and the Web of Science from the inception of the database to April 2022. Subgroup analyses were conducted based on the economic status, region, exposure assessment, risk of bias, and adjustment. Sixty-one studies involving 34,506,975 singleton live births in 15 countries were analyzed. Overall, the risk of bias for most studies (75%) was low. In 39 of 47 term birth studies, the pooled odds ratio of TLBW among term births for per interquartile range (IQR) increases throughout the entire pregnancy was 1.02 (1.01 to 1.03) for PM 2.5 and 1.03 (1.01 to 1.05) for PM 10 after adjustment for covariates. No significant relevance was detected across each trimester period for PM 2.5 . A stronger effect was observed during the second trimester (1.03, 1.01 to 1.06) for PM 10 . There was no increased risk of TLBW in all births associated with IQR increases in PM 2.5 and PM 10 . LBW was associated with PM 2.5 exposure in 4 of 7 studies, but statistical heterogeneity was considerable. In the TLBW subgroup analysis, the effects of PM 2.5 and PM 10 were both greater in studies conducted in advanced countries, studies with low bias, and studies that adjusted for maternal age, infant sex, and parity. Stronger effects were present for PM 2.5 exposure collected from monitoring stations and PM 10 exposure interpolated from the inverse distance weighting model. TLBW may be associated with prenatal exposure to particulate matter, but no critical windows were identified. Stronger associations were observed in advanced countries. Future original study designs need to consider the impact of different exposure assessment modalities and all possible confounding factors. | Prenatal exposure to particulate matter and term low birth weight: systematic review and meta-analysis | 10.1007/s11356-023-26831-7 |
2023-05-01 | The wave fields of coastal bays are comprised of waves generated by far-off storms that enter the bay to combine with waves generated locally by winds inside the bay and regionally outside the bay. In any given location, the resultant wave field varies spatially and temporally, and affects coastal features, such as beaches in estuaries and bays (BEBs). However, wave fields in enclosed bays with tidal shoals are poorly studied, limiting the efficacy of coastal protection and restoration projects in these systems, a critical focus in light of ongoing sea level rise. Here we present observations of the wave field in Tomales Bay, a 20-km-long, narrow, semi-enclosed embayment on the wave-dominated coast of Northern California (USA) with a spring-tide range of 2.5 m. We deployed pressure sensors near several beaches along the linear axis of the bay. Low-frequency waves ( $$4*10^{-2}-2.5*10^{-1}$$ 4 ∗ 10 - 2 - 2.5 ∗ 10 - 1 Hz or 4–25-s period) were not observed further than 4 km of the mouth, delineating the “outer bay” region, where remotely generated swell and regionally generated wind waves could dominate. The wave spectrum of the landward “inner bay” was dominated by fetch-limited waves generated within the bay with frequency $$\ge 2.5*10^{-1}$$ ≥ 2.5 ∗ 10 - 1 Hz. The energy of both ocean waves and locally generated wind waves across all sites were controlled by the tide, but the former by changes in attenuation and the latter likely by modulation of wave generation. Wave energies were low at low tide and high at high tide, but high-frequency wind wave energy was increased during ebb tides while lower-frequency swell energy was reduced during ebb tides, suggesting different mechanisms of tidal influences. Thus, in addition to fluctuations in winds and the presence of ocean waves, tides exert a strong control on the wave energy spectra at coastal features in mesotidal regions. In general, events that may be impactful for BEB morphology are expected to occur when waves due to high winds or high-swell event arrive during high-tide periods. However, no such events were observed during our study and questions remain as to how rarely such events occur across the bay. | Components and Tidal Modulation of the Wave Field in a Semi-enclosed Shallow Bay | 10.1007/s12237-022-01154-x |
2023-05-01 | The present work focused on investigating the corrosion behavior of NiCu low alloy steel in 0.05 M NaHCO 3 solutions with different Cl − concentrations under the aerobic–anoxic condition. The results showed that NiCu steel tended to be pseudo-passivated in the solutions of 0.05 M NaHCO 3 and 0.05 M NaHCO 3 + 0.01 M NaCl exposed to air. The cathodic process transformed from oxygen reduction to the common reduction of oxygen and α -FeOOH, while the anodic process was the iron dissolution. As Cl − increased to 0.1 M, the steel tended to be activity dissolution. Due to the blocking effect of rust layer on the oxygen, the cathodic process transformed to the reduction of α -FeOOH. After the solutions were deoxidized, the cathodic process was controlled by only rust reduction. Meanwhile, both the cathodic process and anodic process of NiCu steel corrosion were significantly inhibited. During the whole aerobic–anoxic immersion, the corrosion rate of NiCu steel increased with Cl − concentration. It was not only related to the promotion of Cl − on the anodic dissolution of steel, but also related to the cathodic reduction of more α -FeOOH generated, which could accelerate the cathodic process. | Effects of Aerobic and Anoxic Conditions on the Corrosion Behavior of NiCu Low Alloy Steel in the Simulated Groundwater Solutions | 10.1007/s40195-022-01490-8 |
2023-05-01 | A novel lanthanum manganese oxide (La 0.96 Mn 0.96 O 3 , LMO) was synthesized for advanced phosphate removal to alleviate water eutrophication process. The adsorbent had a specific surface area of 18.51 m 2 /g with pH at point of zero charge of 6.6; exhibited excellent phosphate adsorption capacity of 168.4 mg/g; performed well in a wide pH range from 3 to 10. The phosphate removal was not interfered by coexisting ions. The adsorbent remained 94.8% of its initial adsorption efficiency after reused for four times. Phosphate adsorption process conformed to pseudo-second-order model (R 2 =0.992) and Langmuir model (R 2 =0.935). Ligand exchange and electrostatic interaction played important roles in phosphate removal. In addition, the actual sewage secondary effluent was used to further verify the phosphate removal performance of LMO. For practical water treatment, the LMO showed high phosphate removal efficiency of 83.4% and low residual P of 0.1 mg/L. LMO is a potential candidate for low-concentration phosphate removal in real water environment. | Advanced removal of phosphate from water by a novel lanthanum manganese oxide: Performance and mechanism | 10.1007/s11356-023-26526-z |
2023-05-01 | This paper presents a numerical model for the evaluation of the active and passive seismic earth pressure coefficients against the retaining structures subjected to pseudo-dynamic loading using the lower bound limit analysis coupled with finite element discretization and second-order cone programming. The active and passive pseudo-dynamic earth pressures are formulated as functions of the earthquake non-dimensional wavelength as well as the local site effects originated from the backfill damping characteristics and the elastic properties of the underlying foundation. Results generally show that the retaining wall tends to instability by increasing the seismic intensity. In particular, it is shown that when the input acceleration at the base of the wall increases, the active and passive lateral earth pressure coefficients undergo increment and decrement, respectively. Moreover, the pseudo-dynamic active and passive earth pressures are bounded between their static and pseudo-static equivalents. Indeed, it is revealed that when trivial wavelengths are encountered, the influence of seismic loading vanishes due to the counteracted inertia force increments and the static solution is reached. On the contrary, when very high wavelengths are assumed, especially for shorter walls, the acceleration fields become homogeneous lending support to the contention that the pseudo-dynamic earth pressure starts from the pseudo-static asymptote values. The soil-wall interface friction angle is also observed to considerably affect the limit earth pressure coefficients due to the augmented shear resistance provision. Furthermore, foundation elasticity is shown to be as important as the backfill damping characteristics in the pseudo-dynamic site response analysis. | Evaluation of the Active and Passive Pseudo-dynamic Earth Pressures using Finite Element Limit Analysis and Second-order Cone Programming | 10.1007/s10706-023-02381-0 |
2023-05-01 | The current approach for the risk assessment of chemicals does not account for the complex human real-life exposure scenarios. Exposure to chemical mixtures in everyday life has raised scientific, regulatory, and societal concerns in recent years. Several studies aiming to identify the safety limits of chemical mixtures determined hazardous levels lower than those of separate chemicals. Following these observations, this study built on the standards set by the real-life risk simulation (RLRS) scenario and investigated the effect of long-term exposure (18 months) to a mixture of 13 chemicals (methomyl, triadimefon, dimethoate, glyphosate, carbaryl, methyl parathion, aspartame, sodium benzoate, EDTA, ethylparaben, butylparaben, bisphenol A and acacia gum) in adult rats. Animals were divided into four dosing groups [0xNOAEL (control), 0.0025xNOAEL (low dose—LD), 0.01xNOAEL (medium dose—MD) and 0.05xNOAEL (high dose-HD) (mg/kg BW/day)]. After 18 months of exposure, all animals were sacrificed, and their organs were harvested, weighed, and pathologically examined. While organ weight tended to be higher in males than in females, when sex and dose were taken into account, lungs and hearts from female rats had significantly greater weight than that of males. This discrepancy was more obvious in the LD group. Histopathology showed that long-term exposure to the chemical mixture selected for this study caused dose-dependent changes in all examined organs. The main organs that contribute to chemical biotransformation and clearance (liver, kidneys, and lungs) consistently presented histopathological changes following exposure to the chemical mixture. In conclusion, exposure to very low doses (below the NOAEL) of the tested mixture for 18 months induced histopathological lesions and cytotoxic effects in a dose and tissue-dependent manner. | A mixture of 13 pesticides, contaminants, and food additives below individual NOAELs produces histopathological and organ weight changes in rats | 10.1007/s00204-023-03455-x |
2023-05-01 | Abstract— The need of traversing the flow gas-dynamic parameters, when trying out new last stages of a steam turbine’s low-pressure cylinders (LPC), is shown. The specific features of pressure measurements according to the pneumometric method by means of probes in the last stages operating in a wet steam (two-phase) medium, with the probe’s receiving holes and pneumatic lines becoming blocked with condensate, are shown. The changeover for using small-size probe heads featuring better measurement accuracy in comparison with large-size heads is substantiated. A universal algorithm for purging the pneumatic lines periodically with atmospheric air for various probes with receiving holes of certain diameters is proposed. The universal algorithm is obtained by supplementing the system with a subroutine that automatically monitors the time delay after closing the purging valves prior to carrying out measurements at the traversing point. At that, excluded are incomplete removal of residual purging air with condensate from the pneumatic lines and excessive time delay before measurements. The algorithm is implemented in improving the previously developed traversing system. Better accuracy of measuring the pressures and flow meridian angles is achieved owing to the use of high-precision transducers in each of the probe measurement channels with the absolute pressure range 0–30 kPa with the accuracy equal to 0.05% of the upper measurement limit. The time taken to process the traversing results is decreased by adding three measurement channels to the system, which operate synchronously with the probe and characterize the turbine operation mode. A modern system for traversing the flow in the gap between blade rings of the last stages has been developed. The results of this development are used in studying the advanced steam turbine LPC compartment on the full-scale test bench at JSC Power Machines. | Improving the Accuracy of Measurements of Gas-Dynamic Parameters in LPC Last Stages Using Modern Flow Traversing System in Studies on a Full-Scale Test Bench | 10.1134/S0040601523050038 |
2023-05-01 | The results of an electron microscopy study of the dislocation structure evolution in polycrystals of Cu–Mn homogeneous solid solutions having an fcc-lattice are presented. A scheme of the dislocation substructure rearrangements identified on the stress-strain curves in the transitions from one stage to another is constructed for the Cu–Mn alloys as a function of the concentration. A critical role of solid solution strengthening in the development of dislocation substructures (DSS) in the Cu–Mn alloys with an fcc crystal lattice is identified, which are the principal deformation carriers for a particular deformation stage. It is shown that the transitions from one DSS type to another occur in specific strain degree intervals ε. It is revealed that every deformation stage has its corresponding DSSs – deformation carriers. A stage-to-stage transition is followed by the formation of new deformation carriers, which is a characteristic feature of the low-stability states of this system. | RETRACTED ARTICLE: Evolution of Dislocation Structure of Polycrystals of Homogeneous Copper-Manganese Solid Solutions Under Conditions of Plastic Deformation | 10.1007/s11182-023-02904-5 |
2023-05-01 | Sarcomas are rare malignancies, the number of reports is limited, and this rarity makes further research difficult even though liposarcoma is one of major sarcomas. 2D cell culture remains an important role in establishing basic tumor biology research, but its various shortcomings and limitations are still of concern, and it is now well-accepted that the behavior of 3D-cultured cells is more reflective of in vivo cellular responses compared to 2D models. This study aimed to establish 3D cell culture of liposarcomas using two different methods: scaffold-based (Matrigel extracellular matrix [ECM] scaffold method) and scaffold-free (Ultra-low attachment [ULA] plate). Lipo246, Lipo224 and Lipo863 cell lines were cultured, and distinctive differences in structures were observed in Matrigel 3D model: Lipo224 and Lipo863 formed spheroids, whereas Lipo246 grew radially without forming spheres. In ULA plate approaches, all cell lines formed spheroids, but Lipo224 and Lipo863 spheroids showed bigger size and looser aggregation than Lipo246. Formalin fixed, paraffin embedded (FFPE) blocks were obtained from all 3D models, confirming the spheroid structures. The expression of MDM2, Ki-67 positivity and MDM2 amplification were confirmed by IHC and DNAscope™, respectively. Protein and DNA were extracted from all samples and MDM2 upregulation was confirmed by western blot and qPCR analysis. After treatment with MDM2 inhibitor SAR405838, DDLPS spheroids demonstrated different sensitivity patterns from 2D models. Taken together, we believed that 3D models would have a possibility to provide us a new predictability of efficacy and toxicity, and considered as one important process in in vitro pre-clinical phase prior to moving forward to clinical trials. | Three dimensional models of dedifferentiated liposarcoma cell lines: scaffold-based and scaffold-free approaches | 10.1007/s13577-023-00865-y |
2023-05-01 | Background and objective Umbilical venous catheters (UVC) and peripherally inserted central catheters (PICC) are commonly used in preterm infants but have been associated with a number of serious complications. We performed a survey in Austria and Germany to assess the use of UVCs and PICCs in preterm infants with a birth weight < 1250 g and associated rates of catheter-related adverse events. Methods Electronic survey of participating centers of the NeoVitaA trial. Main outcome parameter was the reported rates of UVC- and PICC-associated complications (infection, thrombosis, emboli, organ injury, arrhythmia, dislocation, miscellaneous). Results In total, 20 neonatal intensive care units (NICU) providing maximal intensive care in Austria and Germany (level I) were contacted, with a senior neonatologist response rate of 12/20 (60%). The reported rates for UVC with a dwell time of 1–10 days were bacterial infection: 4.2 ± 3.4% (range 0–10%); thrombosis: 7.3 ± 7.1% (0–20%); emboli: 0.9 ± 2.0% (0–5%); organ injury: 1.1 ± 1.9% (0–5%); cardiac arrhythmia: 2.2 ± 2.5% (0–5%); and dislocation: 5.4 ± 8.7% (0–30%); and for PICCs with a dwell time of 1–14 days bacterial infection: 15.0 ± 3.4% (range 2.5–30%); thrombosis; 4.3 ± 3.5% (0–10%); emboli: 0.8 ± 1.6% (0–5%); organ injury: 1.5 ± 2.3% (0–5%); cardiac arrhythmia: 1.5 ± 2.3% (0–5%), and dislocation: 8.5 ± 4.6% (0–30%). Conclusion The catheter-related complication rates reported in this survey differed between UVCs and PICCs and were higher than those reported in the literature. To generate more reliable data on this clinically important issue, we plan to perform a large prospective multicenter randomized controlled trial investigating the non-inferiority of a prolonged UVC dwell time (up to 10 days) against the early change (up to 5 days) to a PICC. Hintergrund und Ziel Nabelvenenkatheter („umbilical venous catheters“ [UVC]) und periphere zentrale Venenkatheter (PICC) werden häufig bei Frühgeborenen eingesetzt, sind jedoch mit einer Reihe von schwerwiegenden Komplikationen verbunden. In Österreich und Deutschland wurde eine Umfrage durchgeführt, um die Verwendung von UVC und PICC bei Frühgeborenen mit einem Geburtsgewicht < 1250 g und die damit verbundenen Raten von katheterbedingten unerwünschten Ereignissen zu bewerten. Methoden Elektronische Befragung der teilnehmenden Zentren der NeoVitaA-Studie. Hauptergebnisparameter waren die gemeldeten Raten von UVC- und PICC-assoziierten Komplikationen (Infektion, Thrombose, Embolie, Organverletzung, Arrhythmie, Dislokation, Sonstiges). Ergebnisse Insgesamt wurden 20 neonatale Intensivstationen (NICU) mit maximaler Intensivpflege in Österreich und Deutschland (Level I) kontaktiert, wobei 12/20 (60 %) von leitenden Neonatologen beantwortet wurden. Die gemeldeten Raten für UVC mit einer Verweildauer von 1 bis 10 Tagen waren bakterielle Infektionen: 4,2 ± 3,4 % (Bereich: 0–10 %); Thrombose: 7,3 ± 7,1 % (0–20 %); Embolie: 0,9 ± 2,0 % (0–5 %); Organverletzung: 1,1 ± 1,9 % (0–5 %); Herzrhythmusstörungen: 2,2 ± 2,5 % (0–5 %); und Dislokation: 5,4 ± 8,7% (0–30 %); und bei PICC mit einer Verweildauer von 1 bis 14 Tagen bakterielle Infektionen: 15,0 ± 3,4 % (Bereich: 2,5–30 %); Thrombose: 4,3 ± 3,5 % (0–10 %); Embolie: 0,8 ± 1,6 % (0–5 %); Organverletzung: 1,5 ± 2,3 % (0–5 %); Herzrhythmusstörungen: 1,5 ± 2,3 % (0–5 %) und Verrenkungen: 8,5 ± 4,6 % (0–30 %). Schlussfolgerung Die in dieser Umfrage berichteten katheterbedingten Komplikationsraten unterschieden sich zwischen UVC und PICC und waren höher als die in der Literatur berichteten. Um zuverlässigere Daten zu diesem klinisch wichtigen Thema zu erhalten, ist eine große prospektive, multizentrische, randomisierte, kontrollierte Studie geplant, in der die Nichtunterlegenheit einer verlängerten UVC-Verweildauer (bis zu 10 Tage) gegenüber dem frühen Wechsel (bis zu 5 Tage) zu einem PICC untersucht werden soll. | Umbilical venous catheter- and peripherally inserted central catheter-associated complications in preterm infants with birth weight < 1250 g | 10.1007/s10354-022-00952-z |
2023-05-01 | Purpose To investigate whether the elevation in metabolic cost of walking on treadmills compared to overground for healthy elderly is related to self-reported anxiety and if changes in self-reported anxiety are related to changes in heart rate. Methods We measured overground preferred walking speed, oxygen consumption rate and heart rates during rest and walking, and self-reported anxiety in 10 elderly (mean age 69.5 ± 3.1 years, 8 males and 2 females). At their preferred speed, the participants first walked overground, then on a high treadmill, and then on a low treadmill. Gross and Net metabolic costs of walking were calculated from the rates of oxygen consumption. Results Gross and net metabolic cost of walking were higher ( p < 0.05) on high treadmill (net cost: 2.64 J kg −1 m −1 ) and low treadmill (net cost: 2.68 J kg −1 m −1 ) compared to overground (net cost: 2.44 J kg −1 m −1 ), and the same was true for heart rate. There were no significant differences ( p > 0.05) in metabolic costs and heart rates between the two treadmill conditions. Self-reported anxiety was higher on the high treadmill compared to overground ( p = 0.004) and compared to low treadmill ( p = 0.02). We found no significant difference ( p > 0.05) for self-reported anxiety between overground and the low treadmill. Conclusion These results show that treadmill walking cannot be adequately generalized to overground walking. The differences found in metabolic cost on treadmills compared to overground were not related to differences in self-reported anxiety. Furthermore, the changes in heart rate are not related to changes in self-reported anxiety. | The elevated metabolic cost of walking at preferred speeds of healthy elderly on treadmills compared to overground is not related to increased self-reported anxiety | 10.1007/s00421-023-05138-y |
2023-05-01 | Towards Zero Thromboembolic Events After Bariatric Metabolic Surgery | 10.1007/s11695-023-06511-8 | |
2023-05-01 | Logistics is a crucial part of every business. The logistics sector not only contributes significantly to Asian economies but also has far-reaching effects on ecological and social concerns. Therefore, it is important to examine the factors that can affect the logistics performance of the country. Hence, the primary objective of the study is to estimate the impact of CO 2 emissions, ICT, and human capital on the logistics performance of the 20 Asian economies. In order to investigate the relationship between the variables, we have employed the OLS, 2SLS, GMM, and panel quantile regression. The estimates of CO 2 emissions and GHG emissions are significantly negative in 2SLS and GMM methods, implying that environmental pollution hurt logistic performance. The estimates of ICT and education are positively significant, suggesting that increased use of internet and higher education rate are crucial in improving logistics performance. In the panel quantile regression model, the estimates of CO 2 , internet, and education are insignificant at most quantiles except at a few higher quantiles. Thus, governments should invest in the development of efficient logistics infrastructure to achieve sustainable development. | Asian logistics industry efficiency under low carbon environment: policy implications for sustainable development | 10.1007/s11356-023-26681-3 |
2023-05-01 | Objective To validate the Tibetan version of the International Prostate Symptom Score (IPSS-Tib) in patients with and without urinary symptoms in a Tibetan population. Methods The validity and reliability of IPSS-Tib were studied in 85 patients with benign prostatic hyperplasia (BPH) and 62 controls without lower urinary tract symptoms (LUTS). Reliability was evaluated using the test−retest method and internal consistency using Cronbach's α , and the construct validity was assessed by the correlation between IPSS-Tib scores and quality of life questions (QoL-Tib). Results The Cronbach’s α coefficient of the IPSS-Tib was 0.80 and of a single IPSS scoring item ranged from 0.77 to 0.86. The IPSS-Tib test−retest reliability was evaluated by the intraclass correlation coefficient, and its average value was 0.79 ( P < 0.001). The mean (SEM, 95% CI) area under the ROC curve for the IPSS-Tib was 0.91 (0.87–0.96). The IPSS-Tib had a high correlation with the QoL-Tib (Spearman’s rank correlation coefficient 0.84, P < 0.01). The mean IPSS score before transurethral resection of the prostate (TURP) was 21.9 (6.8), and dropped to 6.38 (1.54) after TURP ( P < 0.001), and the average difference was 15.52 (6.23), related to the drop from 4.5 (0.9) to 1.46 (0.48) in the QoL ( P < 0.001). Conclusion The IPSS-Tib has good reliability and validity in the diagnosis and symptom severity assessment of patients with BPH in Tibetan areas. It is an ideal assessment tool that can be used in Tibetan-speaking areas for patients with BPH and as a method for evaluating postoperative curative effect assessment of patients with BPH. | Reliability and validity of the Tibetan version of the International Prostate Symptom Score | 10.1007/s00345-023-04368-1 |
2023-05-01 | Purpose Growing evidence have suggested an association between nephrolithiasis and cardiovascular disease (CVD) with unclear mechanism. Oxidized low-density lipoproteins (oxLDL) induces atherosclerosis and was found to be the possible link between these two diseases. Our study aimed to examine the serum, urine and kidney expression of oxLDL in relation to large calcium oxalate (CaOx) renal stone disease. Methods A total of 67 large CaOx dominant renal stone patients and 31 stone-free controls were enrolled in the prospective case–control study. All participants were without known CVD history. Serum, urine, and kidney biopsy were collected before and during percutaneous nephrolithotomy, respectively. Enzyme-linked immunosorbent assays were used to assess serum and urine oxLDL, lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), and high-sensitivity C-reactive protein (hsCRP). Results There was no significantly difference in circulating oxLDL, but serum hsCRP was significantly near two-fold higher in nephrolithiasis patients. Serum hsCRP was also correlated with stone maximal length. Urine oxLDL was significantly higher in the nephrolithiasis group and correlated with serum hsCRP and stone maximal length. Increased oxLDL uptake in kidney was found in nephrolithiasis patients, whereas no significantly renal expression of oxLDL was observed in controls. Conclusions The renal uptake of oxLDL with increased oxLDL excretion from large CaOx renal stone formers, independent of increased circulating oxLDL, is a novel pathological finding in kidney stone disease and brings attention to the possible involvement of renal steatosis in the process of urolithiasis formation. | Increased renal uptake and urine excretion of oxidized LDL is possibly associated with formation of large calcium oxalate nephrolithiasis: a preliminary study | 10.1007/s00345-023-04360-9 |
2023-05-01 | Non-axisymmetric endwall (NAEW) contouring method has shown promising results to reduce secondary losses using both experimental and numerical studies. The parameterized endwall contour shaping redistributes the local static pressure resulting in a reduced effect of loss generating elements. Present study discusses the effect of the fore extension of NAEW shape on secondary flow field at design and off-design incidences numerically for low-pressure (LP) linear turbine cascade. The steady Reynolds averaged Navier-Stokes (RANS) simulations are performed using shear stress transport (SST) based γ − θ turbulence model in commercial solver. The simulations are performed for a low Re = 1.6×10 5 based on blade chord and isentropic exit velocity. The two-part study discusses the effect of upstream extension of NAEW profile at design and off-design incidence cases, respectively. The study observed reduction in total pressure loss coefficient ( $$\bar \omega$$ ω ¯ ) by implementing NAEW contour profiling. The NAEW with 40 % C ax extension is the most favorable case. | Effect of axial extension on parameterized endwall contour with incidence change for low-pressure turbine linear cascade | 10.1007/s12206-023-2109-7 |
2023-05-01 | Background It is yet unknown if the ApneaGraph200 system can replace the Polysomnography system (PSG), which is now the gold standard for obstructive sleep apnea (OSA) diagnosis. We performed a meta-analysis to evaluate the difference in apnea hypopnea index and lowest oxygen saturation levels between the AG200 system and PSG system. Methods Utilizing PubMed, Elsevier, Wanfang, and China National Knowledge Internet (CNKI), a thorough literature search was carried out. Eligible studies contrasting the AG200 system and the PSG system were found by two separate researchers. Review Manager (version 5.3) was adopted for data synthesis. Results The meta-analysis A pooled the comparison of AHI between the AG and PSG groups, and included seven studies involving a total of 419 participants, which revealed that there was a significant difference in AHI between the above two diagnostic methods (standard mean difference (SMD) = − 0.19, 95% confidence interval (CI) = − 0.32 to − 0.05, P = 0.008). As a supplementary, meta-analysis B pooled the comparison of lowest oxygen saturation between the AG and PSG groups and included five studies involving a total of 224 participants. It revealed that there was no significant difference between the AG group and the PSG group (SMD = 0.09, 95% CI − 0.24 to 0.43, P = 0.58). Conclusion The ApneaGraph200 system can be used for the initial screening of OSA patients, but it is not a complete alternative to polysomnography for the diagnosis and severity of the OSA condition. | Can polysomnography be replaced by ApneaGraph200 for OSA diagnosis? A protocol for systematic review and meta-analysis | 10.1007/s00405-022-07815-8 |
2023-04-29 | A comparison study was done on poly (9,9-di-n-octylfluorenyl-2,7-diyl) (PFO)/n-silicon (Si) photodiodes, using pure PFO vs. ZnO nanorods (NRs)-PFO nanocomposite. The nanocomposite was synthesized by mixing scratched-hydrothermally grown ZnO NRs into the prepared PFO solution. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) confirmed the presence of ZnO NRs in PFO, proving successful nanocomposite synthesis. The nanocomposite showed a slight blue-shift in photoluminescence (PL) spectra than pure PFO. The nanocomposite-based photodiode showed improved performance, due to the presence of two heterojunctions (PFO/n-Si and PFO/ZnO NRs) acting as the source of photogenerated electron-hole pairs. A higher current density of ZnO also played an important part in the increase in performance. The photodiodes prepared using PFO-ZnO NRs nanocomposite reported the highest sensitivity at 0 V bias voltage (3920%) and highest responsivity at 8 V bias voltage (0.93 A/W). Lastly, a proposed mechanism diagram was drawn to explain the roles of the two heterojunctions in the workings of the photodiode. | Comparison study on the influence of pure PFO and PFO-ZnO nanorods in PFO/n-Si photodiodes | 10.1007/s10965-023-03557-1 |
2023-04-29 | Background In low- and middle-income countries, approximately two thirds of maternal deaths occur in the postpartum period. Yet, care for women beyond 24 h after discharge is limited. The objective of this systematic review is to summarize current evidence on socio-demographic and clinical risk factors for (1) postpartum mortality and (2) postpartum hospital readmission. Methods A combination of keywords and subject headings (i.e. MeSH terms) for postpartum maternal mortality or readmission were searched. Articles published up to January 9, 2021 were identified in MEDLINE, EMBASE, and CINAHL databases, without language restrictions. Studies reporting socio-demographic or clinical risk factors for postpartum mortality or readmission within six weeks of delivery among women who delivered a livebirth in a low- or middle-income country were included. Data were extracted independently by two reviewers based on study characteristics, population, and outcomes. Included studies were assessed for quality and risk of bias using the Downs and Black checklist for ratings of randomized and non-randomized studies. Results Of 8783 abstracts screened, seven studies were included (total N = 387,786). Risk factors for postpartum mortality included Caesarean mode of delivery, nulliparity, low or very low birthweight, and shock upon admission. Risk factors for postpartum readmission included Caesarean mode of delivery, HIV positive serostatus, and abnormal body temperature. Conclusions Few studies reported individual socio-demographic or clinical risk factors for mortality or readmission after delivery in low- and middle-income countries; only Caesarean delivery was consistently reported. Further research is needed to identify factors that put women at greatest risk of post-discharge complications and mortality. Understanding post-discharge risk would facilitate targeted postpartum care and reduce adverse outcomes in women after delivery. Trial registration PROSPERO registration number: CRD42018103955. | Risk factors for postpartum maternal mortality and hospital readmission in low- and middle-income countries: a systematic review | 10.1186/s12884-023-05459-y |
2023-04-28 | Backgrounds Gynaecological cancer survivors may develop lower limb lymphoedema after surgery, which negatively impacts quality of life. The purposes of this study were (1) to assess the levels of symptom distress, depression, body image, and health-related quality of life (HRQoL); (2) to recognize factors associated with HRQoL related in gynaecologic cancer survivors with lower limb lymphoedema. Methods A cross-sectional study was conducted with convenience sampling of gynaecologic cancer survivors with lower limb lymphoedema. Gynaecologic cancer survivors were assessed for symptom distress, depression, body image, and HRQoL. Multiple regression analysis was conducted to recognize the factors associated with HRQoL. Independent-samples t - test was used to compare symptom distress, depression, body image, and HRQoL by grade of lymphoedema. Results The most common distressing symptoms of lower limb lymphoedema were lower extremity oedema, lower extremity tightness, and lower extremity stiffness. Worse HRQoL was associated with more symptom distress, less satisfaction with body image, a high grade of lymphoedema, and a longer duration of lower limb lymphoedema. These factors explained 76.5% of the variance in HRQoL. Gynaecologic cancer survivors with late grade lymphoedema experienced lower HRQoL and higher levels of symptom distress, depression, and greater dissatisfaction with body image than those who had early grade lymphoedema. Conclusions Symptom distress had the strongest association with overall HRQoL and with all individual domains of HRQoL, except mental function. These results suggest that educating gynaecologic cancer survivors to assess lower limb lymphoedema-related problems, providing symptom management, and guiding survivors in physical activity to relieve lower extremity discomfort can improve HRQoL. | Factors associated with health-related quality of life in gynaecologic cancer survivors with lower limb lymphedema: a cross-sectional study in Taiwan | 10.1186/s12905-023-02340-0 |
2023-04-27 | The solubility of Na 2 O·xAl 2 O 3 in a NaF-KF-AlF 3 -based low-temperature electrolyte was investigated, and the influence of electrolyte temperature at 750 ℃, CR = 1.3–1.4, CaF 2 , and LiF on the alumina solubility was studied. The dissolution rate of alumina in the electrolyte was determined by measuring the alumina concentration in the electrolyte at different times with an oxygen analyzer. The results showed that in the NaF-KF-AlF 3 -based low-temperature electrolyte, the dissolution rate of alumina in Na 2 O·xAl 2 O 3 was faster than that of Al 2 O 3 . As the Na 2 O content in alumina increased, the dissolution rate increased. Similarly, a higher CR of NaF-KF-AlF 3 and a higher temperature of the molten salt (750–850 °C) increased the dissolution rate of alumina in the electrolyte. The dissolution rate of alumina in NaF-KF-AlF 3 decreased after adding CaF 2 and LiF. According to the kinetics analysis, the dissolution rate of alumina followed the zero-order reaction rate law from 0–5 min, which showed that it depended on the amount of alumina absorbed in the electrolyte in the first five minutes. | Solubility of Na2O·xAl2O3 in NaF-KF-AlF3-based low-temperature electrolyte | 10.1007/s43938-023-00027-4 |
2023-04-27 | The single high-dose application of biochar to increase rice yield has been well reported. However, limited information is available about the long-term effects of increasing rice yield and soil fertility. This study was designed to perform a 6-year field experiment to unveil the rice yield with time due to various biochar application strategies. Moreover, an alternative strategy of the Annual Low dose biochar application (AL, 8 × 35% = 2.8 t ha −1 ) was also conducted to make a comparison with the High Single dose (HS, 22.5 t ha −1 ), and annual Rice Straw (RS, 8 t ha −1 ) amendment to investigate the effects on annual rice yield attributes and soil nutrient concentrations. Results showed that the rice yield in AL with a lower biochar application exceeded that of HS significantly ( p < 0.05 ) in the 6th experimental year. The rice yield increased by 14.3% in RS, 10.9% in AL, and 4.2% in HS. The unexpectedly higher rice yield in AL than HS resulted from enhanced soil total carbon (TC), pH, and available Ca. However, compared to AL, liable carbon fraction increased by 33.7% in HS, while refractory carbon fraction dropped by 22.3%. Likewise, biochar characterization showed that more oxygen functional groups existed in HS than in AL. Decreasing inert organic carbon pools due to the constant degradation of the aromatic part of biochar in HS led to a lower soil TC than AL, even with a higher amount of biochar application. Likewise, the annual depletion lowered the soil pH and available Ca declination in HS. Based on the obtained results, this study suggested AL as a promising strategy to enhance rice productivity, soil nutrient enrichment, and carbon sequestration in the paddy ecosystem. Graphic abstract Annual Low-rate biochar strategy showed higher rice yields than High Single in the 6th year. Higher total carbon, pH, and Ca 2+ led to higher rice yields in Annual Low than High Single. Higher aromatic carbon loss in High Single contributed to lower inert organic carbon. | The implication from six years of field experiment: the aging process induced lower rice production even with a high amount of biochar application | 10.1007/s42773-023-00218-w |
2023-04-25 | Ultra-high strength low alloy (UHSLA) steels are one of pivotal materials used in industrial sector. Its diversified compositions and characteristic mechanical properties as per service requirement have created an inevitable place for this steel class. The current study has been carried out on the deformation behavior and plastic instability of newly developed (UHSLA steel) XF1700 over a wide temperature range $${T}_{\mathrm{r}}$$ T r to near $${T}_{\mathrm{m}}$$ T m (298-1673 K) and at quasi-static (0.01-1/s) as well as dynamic (10-10 4 /s) conditions. Such a wide range of data were obtained by utilizing chemical composition of this alloy system in JMatPro (an efficient software based on CALPHAD module). The effect of temperature with increasing strain and strain rate has been quantified in terms of a four-parameter exponential model based on two Z (Zener–Hollomon) parameters $${Z}_{\mathrm{m}}$$ Z m and $${Z}_{\mathrm{n}}$$ Z n , as such to predict cold, warm and hot deformation mechanism by a subsection method. The novelty of this work lies in its simple mathematical model that can describe the deformation behavior of a material for temperature range $${T}_{\mathrm{r}}$$ T r to near $${T}_{\mathrm{m}}$$ T m , considering the temperature compensated strain and strain rate factors. EBSD analysis was carried out for microstructural analysis to support the deformation behavior and plastic instability mechanism. Based on four-parameter exponential model, the deformation stability criteria have also been elucidated for all the three zones: Zone I, cold forming zone (298-673 K); Zone II, warm forming zone (673 < T ≤ 973 K) and Zone III, hot forming zone (973 < T ≤ 1673 K). Through non-linear regression model in SPSS software, material parameters describing deformation behavior and plastic instability were segregated in parts and the four-parameter exponential model has been verified which is found to be in excellent agreement with available data. The AARE obtained was 2.03% (zone I), 7.17% (zone II) and 4.07% (zone III), respectively, while the overall AARE was 4.42%. Graphical abstract | Deformation Behavior and Plastic Instability of Ultra-High Strength Low Alloy Steel over Wide Temperature and Velocity Range | 10.1007/s11665-023-08145-4 |
2023-04-25 | Enhanced phosphorus treatment and recovery has been continuously pursued due to the stringent wastewater discharge regulations and a phosphate supply shortage. Here, a new adsorption-membrane separation strategy was developed for rational reutilization of phosphate from sea cucumber aquaculture wastewater using a Zr-modified-bentonite filled polyvinyl chloride membrane. The asobtained polyvinyl chloride/Zr-modified-bentonite membrane was highly permeability (940 L/(m 2 ·h)), 1–2 times higher than those reported in other studies, and its adsorption capacity was high (20.6 mg/g) when the phosphate concentration in water was low (5 mg/L). It remained stable under various conditions, such as different pH, initial phosphate concentrations, and the presence of different ions after 24 h of adsorption in a cross-flow filtration system. The total phosphorus and phosphate removal rate reached 91.5% and 95.9%, respectively, after the membrane was used to treat sea cucumber aquaculture wastewater for 24 h and no other water quality parameters had been changed. After the purification process, the utilization of the membrane as a new source of phosphorus in the phosphorus-free f/2 medium experiments indicated the high cultivability of economic microalgae Phaeodactylum tricornutum FACHB-863 and 1.2 times more chlorophyll a was present than in f/2 medium. The biomass and lipid content of the microalgae in the two different media were similar. The innovative polyvinyl chloride/Zr-modified-bentonite membrane used for phosphorus removal and recovery is an important instrument to establish the groundwork for both the treatment of low concentration phosphate from wastewater as well as the reuse of enriched phosphorus in required fields. | Highly efficient and selective removal of phosphate from wastewater of sea cucumber aquaculture for microalgae culture using a new adsorption-membrane separation-coordinated strategy | 10.1007/s11783-023-1720-2 |
2023-04-24 | The derived diagram defines three main ranges of hydrogen concentration in the metal, which have their own specific mechanisms of hydrogen influence on the characteristics of strength and ductility of the pipeline steel. It has been demonstrated that the nature of the hydrogen effect mechanism depends on the ratio of diffusible $$C_{{{\text{H}}\left( {{\text{dif}}} \right)}}$$ C H dif and residual (trapped) hydrogen $$C_{{{\text{H}}\left( {{\text{res}}} \right)}}$$ C H res in the steel. A specific effect has been found, namely: at the hydrogen concentration $$C_{{\text{H}}} \cong 0.01{\text{-}}0.2\;{\text{ppm}}$$ C H ≅ 0.01 - 0.2 ppm where all hydrogen is practically diffusible, the plastic deformation of the steel is facilitated, i.e., the deforming of the material takes place more easily. At the concentration range $$C_{{\text{H}}} \cong 0.8{\text{-}}10\;{\text{ppm}}$$ C H ≅ 0.8 - 10 ppm , where the trapped hydrogen prevails, the mechanism of hydrogen embrittlement of the steel is completely dominated. Therefore, the hydrogen concentration range beginning from $$C_{{\text{H}}} \cong 0.8\;{\text{ppm}}$$ C H ≅ 0.8 ppm can be considered as critical. The range of values of hydrogen concentration in the metal $$C_{{\text{H}}} \cong 0.2{\text{-}}0.8\;{\text{ppm}}$$ C H ≅ 0.2 - 0.8 ppm is a transition zone where the simultaneous coexistence of these two mechanisms is possible. The constructed diagram can be applied for the interpretation of the inspection results of long-term operated pipelines, and also for the choice of materials for the construction of new networks for hydrogen transportation. | Special Diagram for Hydrogen Effect Evaluation on Mechanical Characterizations of Pipeline Steel | 10.1007/s11665-023-08215-7 |
2023-04-24 | Prevention of hydrate plugs during oil and natural gas transportation in the pipeline network is challenging and may require significant operating expenditure. Synthetic inhibitors are deployed in large volumes to inhibit hydrate formation, and these inhibitors are highly expensive and toxic to the environment. Consequently, this study investigates the effectiveness of cassava ( Manihot esculenta ) leaf extract as an environmentally friendly, biodegradable, and cost-efficient novel green inhibitor of gas hydrate. Cassava is a tropical plant cultivated majorly in Nigeria, and its leaf is, in almost all cases, discarded as waste. In this study, an extract is made from cassava leaf and used in varying weight percentages as hydrate inhibitors using a locally fabricated mini flow. Results show cassava leaf extract (CLE) performed significantly better than conventional inhibitor methanol (MeOH) at a higher weight percentage. The presented results show that at varying weights of 0.02 wt%, 0.04 wt%, and 0.06 wt% of the CLE, the final pressures were found to be the pressures were found to be 29 psi, 27 psi, and 24 psi, respectively. These pressures indicates that more gas was converted to hydrate with the lower pressure value in the system. These results were compared with 2 wt%, 4 wt%, and 6 wt% of MeOH, with a differential pressure of 28 psi, 46 psi, and 50 psi, respectively. CLE’s gas hydrate inhibition capacity was found at pressure conditions of 51.7 psi, 55 psi, and 60 psi for 0.02 wt%, 0.04 wt%, and 0.06 wt%, respectively. These results demonstrate that CLE performed significantly better than methanol as a gas hydrate inhibitor, despite being used in a much lower dosage than methanol, which had inhibition pressures conditions of 53.3 psi, 23.3 psi, and 16.7 psi for 2 wt%, 4 wt%, and 6 wt%, respectively. | Experimental investigation of cassava (Manihot esculenta) leaf extract as a green inhibitor of gas hydrate formation | 10.1007/s13399-023-04213-w |
2023-04-24 | Background Osteoporosis is a degenerative disease characterized by reduced bone mass, with low peak bone mass being the predominant manifestation during development and having an intrauterine origin. Pregnant women at risk of preterm delivery are commonly treated with dexamethasone to promote fetal lung development. However, pregnant dexamethasone exposure (PDE) can lead to reduced peak bone mass and susceptibility to osteoporosis in offspring. In this study, we aimed to investigate the mechanism of PDE-induced low peak bone mass in female offspring from the perspective of altered osteoclast developmental programming. Methods 0.2 mg/kg.d dexamethasone was injected subcutaneously into rats on gestation days (GDs) 9–20. Some pregnant rats were killed at GD20 to remove fetal rat long bones, the rest were delivered naturally, and some adult offspring rats were given ice water swimming stimulation for two weeks. Results The results showed that the fetal rat osteoclast development was inhibited in the PDE group compared with the control group. In contrast, the adult rat osteoclast function was hyperactivation with reduced peak bone mass. We further found that the promoter region methylation levels of lysyl oxidase (LOX) were decreased, the expression was increased, and the production of reactive oxygen species (ROS) was raised in PDE offspring rat long bone before and after birth. Combined in vivo and in vitro experiments, we confirmed that intrauterine dexamethasone promoted the expression and binding of the glucocorticoid receptor (GR) and estrogen receptor β (ERβ) in osteoclasts and mediated the decrease of LOX methylation level and increase of expression through upregulation of 10–11 translocator protein 3 (Tet3). Conclusions Taken together, we confirm that dexamethasone causes osteoclast LOX hypomethylation and high expression through the GR/ERβ/Tet3 pathway, leading to elevated ROS production and that this intrauterine epigenetic programming effect can be carried over to postnatal mediating hyperactivation in osteoclast and reduced peak bone mass in adult offspring. This study provides an experimental basis for elucidating the mechanism of osteoclast-mediated intrauterine programming of low peak bone mass in female offspring of PDE and for exploring its early targets for prevention and treatment. Video Abstract | LOX overexpression programming mediates the osteoclast mechanism of low peak bone mass in female offspring rats caused by pregnant dexamethasone exposure | 10.1186/s12964-023-01115-2 |
2023-04-24 | Background In most areas of China, mothers typically do not participate in early care of preterm infants in NICU. This study aims to examine the early experience of mothers of preterm infants participating in skin-to-skin contact combined with non-nutritive comfort sucking in China. Methods This qualitative research study used one-on-one, face-to-face, semi-structured in-depth interviews. Eighteen mothers who participated in early skin-to-skin contact combined with non-nutritive comfort sucking were interviewed in the NICU of a tertiary children’s hospital in Shanghai between July and December 2020. Their experiences were analyzed using the inductive topic analysis method. Results Five themes about skin-to-skin contact combined with non-nutritive comfort sucking were identified, including alleviation of maternal anxiety and fear during mother infant separation, reshaping the maternal role, promotion of active breast pumping, enhances the mother’s willingness to actively breast feed and building the maternal confidence in baby care. Conclusion Skin-to-skin contact combined with non-nutritive comfort sucking in the NICU can not only enhance the identity and responsibility of the mother’s role, but also provide non-nutritive sucking experience for promoting the establishment of oral feeding in preterm infants. | The clinical experience of early skin-to-skin contact combined with non-nutritive comfort sucking in mothers of preterm infants: a qualitative study | 10.1186/s12884-023-05581-x |
2023-04-24 | In this work, we study the information scrambling and the entanglement dynamics in the complex Brownian Sachdev-Ye-Kitaev (cBSYK) models, focusing on their dependence on the charge density n . We first derive the effective theory for scramblons in a single cBSYK model, which gives closed-form expressions for the late-time OTOC and operator size. In particular, the result for OTOC is consistent with numerical observations in [ 1 ]. We then study the entanglement dynamics in cBSYK chains. We derive the density dependence of the entanglement velocity for both Rényi entropies and the Von Neumann entropy, with a comparison to the butterfly velocity. We further consider adding repeated measurements and derive the effective theory of the measurement induced transition which shows U(2) L ⊗ U(2) R symmetry for non-interacting models. | Information scrambling and entanglement dynamics of complex Brownian Sachdev-Ye-Kitaev models | 10.1007/JHEP04(2023)105 |
2023-04-22 | Anaerobic digestion, a renewable energy source, is the degradation of organic waste into biogas, mainly composed of CH 4 and CO 2 . The sector is expanding rapidly due to its multiple environmental and economic benefits. This process is implemented industrially in concrete structures that are in direct contact with the biowaste being digested and the gas produced. Both phases can damage concrete through (i) the presence of volatile fatty acids, dissolved CO 2 , ammonium, and microbial biofilm in the liquid phase, and (ii) high concentrations of CO 2 and various concentrations of H 2 S in the gas phase. In order to develop more sustainable concrete biogas units, long-term, in-situ experiments were carried out in a semi-industrial scale digester to provide new insights into the performance levels and deterioration mechanisms of various low-CO 2 binders, including alkali-activated metakaolin (geopolymer), alkali-activated slag (AAS), and supersulfated cements (SSC), in comparison to calcium aluminate cement (CAC) and Portland cement based matrices. In the running conditions explored, carbonation of the cementitious matrices was predominant over other deterioration phenomena in both the digester liquid and the gas phases. Alkali-activated metakaolin and calcium aluminate cement performed better with few degradations observed. Supersulfated cements and alkali-activated slag showed an intermediate behaviour with good performance in the acidic liquid phase but low performance in the CO 2 -rich gas phase. Graphical abstract | Potential of low carbon materials facing biodeterioration in concrete biogas structures | 10.1617/s11527-023-02174-0 |
2023-04-21 | The Low Code Development Platform (LCDP) is a versatile platform to handle process, database, mobile and web based applications. The platform provides us opportunity to digitize the activities in IT, telecommunication, government and all other industries as well as different departments of the organization in the form of applications. The manufacturing industry can also incorporate low-code apps for data analysis and their manufacturing processes to automate the process. This research work has proposed a novel sustainable LCDP with optimization techniques for data analysis. The proposed platform allows user to execute data analysis applications in optimization and without optimization mode. The result shows that optimized LCDP reduces both space and time required for the any type of application. | Optimization for achieving sustainability in low code development platform | 10.1007/s12008-023-01338-0 |
2023-04-21 | The TENO-family schemes (Fu et al. in J Comput Phys 305: 333–359, 2016) have been demonstrated to perform well for compressible gas dynamics and turbulent flow predictions on structured meshes. However, the extension of the TENO schemes to unstructured meshes is non-trivial and challenging, particularly when the multiple design objectives are pursued simultaneously, i.e., restoring the high-order accuracy in smooth regions, retaining the low numerical dissipation for small-scale features, maintaining the sharp shock-capturing property, and featuring the good numerical robustness for high-Mach flows. In this work, a family of very-high-order (up to seventh-order accuracy) robust finite-volume TENO schemes with dual ENO-like stencil selection for unstructured meshes is proposed. The stencils include one large stencil and several small stencils. The novelty originates from a so-called dual ENO-like stencil selection strategy. Following a strong scale separation, the ENO-like stencil selection procedure with a small $$C_T$$ C T is first enforced among all the candidates such that the high-order candidate scheme on the large stencil is adopted for the final reconstruction when the local flow is smooth. If the large stencil is judged to be crossed by discontinuities, a second ENO-like stencil selection with a relatively large $$C_T$$ C T is applied to all the left small stencils and the ENO property is obtained by selecting the smooth small stencils which are not crossed by discontinuities. The smaller $$C_T$$ C T in the first stage ensures that the high-order reconstruction is restored for smooth flow scales with higher wavenumbers. On the other hand, the larger $$C_T$$ C T in the second stage can enforce a strong nonlinear adaptation for capturing discontinuities with better robustness. Such a dual ENO-like stencil selection strategy introduces an explicit scale separation and deploys the optimal strategy for different types of flows correspondingly. Without parameter tuning, a set of benchmark simulations has been conducted to validate the performance of the proposed TENO schemes. Numerical results demonstrate the good numerical robustness and the low-dissipation property for highly compressible flows with shockwaves. | High-Order Finite-Volume TENO Schemes with Dual ENO-Like Stencil Selection for Unstructured Meshes | 10.1007/s10915-023-02199-1 |
2023-04-20 | The low-temperature detection of ammonia gas (NH 3 ) is essential in daily life and environment protection. In this work, Au nanoparticle–functionalized ZnSnO 3 cubes have been synthesized by a simple solution-based chemical method. Surface morphology characterization and chemical state analysis were combined to indicate that the Au nanoparticles (NPs) were well contacted with ZnSnO 3 cubes to form the Schottky barrier–type junctions from characterization results. Based on the chemical catalysis and the Schottky barrier, the sensor based on Au-ZnSnO 3 cubes demonstrated excellent response (94.3 to 100 ppm) and better selectivity to ammonia gas at low temperature (80 °C) with the fast response/recovery time of 8/5 s. Meanwhile, the sensor exhibited good repeatability stability and high selectivity towards ammonia among other test gases. The sensing mechanism was proposed in terms of the combination of ZnSnO 3 cube structure and catalytic activity of Au nanoparticles loaded. This work provides an efficient strategy for the fabrication of NH 3 sensors at low temperature. Graphical abstract | Enhanced ammonia sensing performance of Au nanoparticle–functionalized ZnSnO3 cubes at low temperature | 10.1007/s11051-023-05738-x |
2023-04-20 | Background AP2/ERF transcription factors (AP2/ERFs) are important regulators of plant physiological and biochemical metabolism. Evidence suggests that AP2/ERFs may be involved in the regulation of bud break in woody perennials. Green tea is economically vital in China, and its production value is significantly affected by the time of spring bud break of tea plant. However, the relationship between AP2/ERFs in tea plant and spring bud break remains largely unknown. Results A total of 178 AP2/ERF genes ( CsAP2/ERFs ) were identified in the genome of tea plant. Based on the phylogenetic analysis, these genes could be classified into five subfamilies. The analysis of gene duplication events demonstrated that whole genome duplication (WGD) or segmental duplication was the primary way of CsAP2/ERFs amplification. According to the result of the Ka/Ks value calculation, purification selection dominated the evolution of CsAP2/ERFs . Furthermore, gene composition and structure analyses of CsAP2/ERFs indicated that different subfamilies contained a variety of gene structures and conserved motifs, potentially resulting in functional differences among five subfamilies. The promoters of CsAP2/ERFs also contained various signal-sensing elements, such as abscisic acid responsive elements, light responsive elements and low temperature responsive elements. The evidence presented here offers a theoretical foundation for the diverse functions of CsAP2/ERFs . Additionally, the expressions of CsAP2/ERFs during spring bud break of tea plant were analyzed by RNA-seq and grouped into clusters A-F according to their expression patterns. The gene expression changes in clusters A and B were more synchronized with the spring bud break of tea plant. Moreover, several potential correlation genes, such as D-type cyclin genes, were screened out through weighted correlation network analysis (WGCNA). Temperature and light treatment experiments individually identified nine candidate CsAP2/ERFs that may be related to the spring bud break of tea plant. Conclusions This study provides new evidence for role of the CsAP2/ERFs in the spring bud break of tea plant, establishes a theoretical foundation for analyzing the molecular mechanism of the spring bud break of tea plant, and contributes to the improvement of tea cultivars. | Comprehensive analysis and expression profiles of the AP2/ERF gene family during spring bud break in tea plant (Camellia sinensis) | 10.1186/s12870-023-04221-y |
2023-04-19 | The polyethylene (PE)-based low-smoke halogen-free flame-retardant composites by introducing clay-based organic sheet silicates (COSS) into PE and ethylene–vinyl acetate copolymer (EVA) blends were prepared by melt blending method. COSS with hydroxyl and organic functional groups on the surface had a good compatibility with the polymer matrix, which favored their uniform dispersion in the polymer matrix. The introduction of COSS restricted the movement of molecular chains and raised the thermal decomposition temperature of the polymer. Meanwhile, the storage modulus and complex viscosity of the materials were raised, and the internal plastic deformation of the materials was enhanced. When the COSS content was 1 wt %, the tensile strength reached 14.7 MPa, and the elongation at break was 596%. The introduced COSS could weaken the regularity of the molecular chain, generate many holes and carriers, and reduce the crystallization ability and volume resistivity of the material. Significantly, a low addition of 3 wt % COSS could improve the density and uniformity of the carbon layer and greatly alleviate the dripping phenomenon during the burning process of the material. With the addition of 7 wt % COSS, the limiting oxygen index (LOI) of the material could reach 28.8%, and the material had a good stiffness balance and significant anti-drip effect. | High-performance low-smoke halogen-free flame-retardant composites for Fuxing electric multiple units via synergistic effects of char formation and anti-dripping of clay-based organic sheet silicates | 10.1007/s42114-023-00670-z |
2023-04-19 | Low voltage oxide thin-film transistors (TFTs) operating below 1.0 V were developed using a high dielectric constant tantalum oxide produced by thermal oxidation. Thermal oxidation was carried out at 400, 500 and 600 °C under an oxygen atmosphere. The tantalum oxide was evaluated by X-ray photoelectron spectroscopy (XPS). XPS confirmed the binding energy of Ta4f, indicating the binding state of tantalum oxide. The bottom gate oxide TFT with the gate insulator of tantalum oxide grown at 500 °C exhibited mobility of 26.7 cm 2 /V s and a threshold voltage of 1.3 V. The transfer characteristics at the drain voltages below 1.0 V show its applicability to low voltage operation below 1 V. The bootstrapped inverter with developed oxide TFTs operated well at the 1.0 and 2.0 V operation voltages. Graphical Abstract | Low Voltage a-IGZO Thin Film Transistor Using Tantalum Oxide by Thermal Oxidation | 10.1007/s13391-023-00431-6 |
2023-04-19 | Considering the significance of low-energy electrons (LEEs; 0–20 eV) in radiobiology, the sensitization potential of gold nanoparticles (AuNPs) as high-flux LEE emitters when irradiated with sub-keV electrons has been suggested. In this study, a track-structure Monte Carlo simulation code using the dielectric theory was developed to simulate the transport of electrons below 50 keV in gold. In this code, modifications, particularly for elastic scattering, are implemented for a more precise description of the LEE emission in secondary electron emission. This code was validated using the secondary electron yield and backscattering coefficient. To ensure dosimetry accuracy, we further verified the code for energy deposition calculations using the Monte Carlo toolkit, Geant4. The development of this code provides a basis for future studies regarding the role of AuNPs in targeted radionuclide radiotherapy. | A refined Monte Carlo code for low-energy electron emission from gold material irradiated with sub-keV electrons | 10.1007/s41365-023-01204-4 |
2023-04-19 | Photobiomodulation therapy (PBMT) causes stimulatory effects that raise cell metabolism. The study aimed to evaluate the effects of PBMT on the endothelial function of healthy individuals. It was a controlled, randomized, crossover, triple-blind trial with 22 healthy volunteers (female: 77.3%), aged 25.45 years which were randomly divided into three groups. PBMT with gallium-aluminum-arsenide (GaAlAs) diode laser (810 nm, continuous-wave mode, 1000 mW, 0.28 cm 2 ) was applied over the radial and ulnar artery regions in two parallel spots: group 1—30 J ( n = 22, 107 J/cm 2 ) per spot; group 2—60 J ( n = 22, 214 J/cm 2 ) per spot; and group 3—placebo ( n = 22, sham). The endothelial function was measured before and immediately after PBMT by the flow-mediated dilation technique (%FMD) with high-resolution ultrasound. Statistical analysis was made with ANOVA for repeated measures, the effect size was measured by Cohen’s d , and results are presented as mean and standard error (or 95% confidence intervals). A p -value < 0.05 was considered statistically significant. The %FMD increases 10.4% with 60 J (mean difference = 0.496 mm, 95% CI = 0.42 to 0.57, p < 0.001), 7.3% with 30 J (mean difference = 0.518 mm, 95% CI = 0.44 to 0.59, p < 0.001), and 4.7% with placebo (mean difference = 0.560 mm, 95% CI = 0.48 to 0.63, p < 0.001). We found a small effect size ( p = 0.702; d de Cohen = 0.24) without statistical difference between interventions. PBMT with the energy density of 60 J and 30 J did not improve endothelial function. Trial registration number: NCT03252184 (01/09/2017). | Effects of photobiomodulation therapy (PBMT) over endothelial function in healthy individuals: a preliminary crossover clinical trial | 10.1007/s10103-023-03762-w |
2023-04-18 | The present study examines the influence of successive treatments on the fiber surface (NaOH, hydrogen peroxide, and acetic anhydride). The palm petiole fibers were incorporated as reinforcement in linear low-density polyethylene (LLDPE) composites with a loading of 15 wt% and evaluated for mechanical, morphological, and dynamic mechanical properties. The effect of treatments on fiber surfaces has been confirmed using FTIR. The scanning electron microscopy (SEM) results showed that the enhanced interfacial adhesion between the fibers and the matrix makes treated composites more rigid and homogeneous, which means that the fibers are distributed uniformly. The tensile modulus and flexural strength were all enhanced by adding 15% of untreated palm petiole fibers recorded at 598 MPa and 15.56 MPa, respectively, while the tensile strength was decreased. Palm-petiole fiber composites’ storage modulus increased, and the acetylated-alkali fiber (FNA) reinforced LLDPE composite showed the highest storage modulus. Loss modulus increased when palm petiole fibers were strengthened. The Tan delta of composites made from palm petiole fibers was low initially but expanded with fiber addition. We concluded that successive treatments improve the performance of the palm petiole fiber residue and have the potential to create a new type of sustainable and eco-friendly material for various applications. | Effect of fiber surface treatment on the mechanical, morphological, and dynamic mechanical properties of palm petiole fiber/LLDPE composites | 10.1007/s13399-023-04197-7 |
2023-04-18 | Background Cholesterol plays a vital role in multiple physiological processes. Cellular uptake of cholesterol is mediated primarily through endocytosis of low-density lipoprotein (LDL) receptor. New modifiers of this process remain to be characterized. Particularly, the role of fasting- and CREB-H-induced (FACI) protein in cholesterol homeostasis merits further investigation. Methods Interactome profiling by proximity labeling and affinity purification − mass spectrometry was performed. Total internal reflection fluorescence microscopy and confocal immunofluorescence microscopy were used to analyze protein co-localization and interaction. Mutational analysis was carried out to define the domain and residues required for FACI localization and function. Endocytosis was traced by fluorescent cargos. LDL uptake in cultured cells and diet-induced hypercholesterolemia in mice were assessed. Results FACI interacted with proteins critically involved in clathrin-mediated endocytosis, vesicle trafficking, and membrane cytoskeleton. FACI localized to clathrin-coated pits (CCP) on plasma membranes. FACI contains a conserved DxxxLI motif, which mediates its binding with the adaptor protein 2 (AP2) complex. Disruption of this motif of FACI abolished its CCP localization but didn’t affect its association with plasma membrane. Cholesterol was found to facilitate FACI transport from plasma membrane to endocytic recycling compartment in a clathrin- and cytoskeleton-dependent manner. LDL endocytosis was enhanced in FACI-overexpressed AML12 cells but impaired in FACI-depleted HeLa cells. In vivo study indicated that hepatic FACI overexpression alleviated diet-induced hypercholesterolemia in mice. Conclusions FACI facilitates LDL endocytosis through its interaction with the AP2 complex. | FACI is a novel clathrin adaptor protein 2-binding protein that facilitates low-density lipoprotein endocytosis | 10.1186/s13578-023-01023-5 |
2023-04-17 | R-1132a is increasingly being considered as a low global warming potential component in alternative mixtures to R-23 in specialized low temperature and ultra-low temperature refrigeration systems. Though the thermodynamic properties of R-1132a were investigated in several studies up to 2018, reinvestigations have been carried out in recent years. In order to contribute toward these renewed measurements, the critical parameters of R-1132a were experimentally re-determined. Thirty-two vapor pressures from 240 K to the critical temperature, fifteen saturated vapor and six saturated liquid densities above 254 K and the PvT properties in both the vapor phase (98 points) and liquid phase (34 points) from densities of 50 kg·m −3 to 760 kg·m −3 were also measured. Specific correlations for each of these properties were optimized and compared to previously available data from the literature. Additionally, the Peng–Robinson equation of state was used to represent the aforementioned properties and further utilized to determine the enthalpy and entropy of R-1132a. | PvT Properties and Thermodynamic Property Correlations for the Low Global Warming Potential Hydrofluoroolefin Refrigerant R-1132a (1,1-Difluoroethene) | 10.1007/s10765-023-03184-4 |
2023-04-17 | Titanium and its alloys have already been widely used as implant materials due to their outstanding mechanical characteristics and biocompatibility. Notwithstanding this, researchers and businesses alike have continued to actively pursue superior alloys since there are still problems which need urgent consideration. One of these is a noteworthy difference in the implant material’s elastics modulus and that of natural bone, which result into an issue of stress shielding. With prolonged use Ti alloys releases dangerous ions. The Ti alloy surface has a low bioactivity, which prolongs the healing process. β-Ti alloys could be used as viable alternatives when creating dental implants. Additionally, β-Ti alloys characteristics, such as low Young modulus, increased strength, appropriate biocompatibility, and strong abrasion and corrosion resistance, serve as the necessary evidence. Ti alloys when altered structurally, chemically, and by thermomechanical treatment thereby enabling the creation of material which can match the requirements of a various clinical practise scenarios. Additional research is needed which can focused on identifying next century Ti alloys consisting of some more compatible phase and transforming the Ti alloys surface from intrinsically bioinert to bioactive to prevent different issues. In order to give scientific support for adopting β-Ti-based alloys as an alternative to cpTi, this paper evaluates the information currently available on the chemical, mechanical, biological, and electrochemical properties of key β-titanium alloys designed from the past few years. This article is also focusing on β-titanium alloy, its properties and performance over other type of titanium alloy such as α titanium alloys. However, in-vivo research is needed to evaluate novel β titanium alloys to support their use as cpTi alternatives. | A review—metastable β titanium alloy for biomedical applications | 10.1186/s44147-023-00196-7 |
2023-04-17 | The paper summarizes the conditions that are necessary to secure accurate measurements of the thermal conductivity of fluids using the transient hot-wire technique. The paper draws upon the development of the method over five decades to produce a prescription for its use. The purpose is to provide guidance on the implementation of the method to those who wish to make use of it for the first time. It is shown that instruments of the transient hot-wire type can produce measurements of the thermal conductivity with the smallest uncertainty yet achieved (± 0.2%). This can be achieved either when a finite element method (FEM) is employed to solve the relevant heat transfer equations for the instrument or when an approximate analytic solution is used to describe it over a limited range of experimental times from 0.1 s to 1 s. As well as establishing the constraints for the proper operation of the instrument we consider the means that should be employed to demonstrate that the experiment operates in accordance with the theoretical model of it. If the constraints are all satisfied then an uncertainty in thermal conductivity measurements of as little as ± 0.2–0.5% can be obtained for gases and liquids over a wide range of thermodynamic state from 0.1 MPa to 700 MPa and temperatures from 70 K to 500 K with the exception of near critical conditions. It is observed that many applications of the transient hot-wire technique do not conform to the constraints set out here and therefore may be burdened with very much greater uncertainties, sometimes large enough to render the results meaningless. | Correct Use of the Transient Hot-Wire Technique for Thermal Conductivity Measurements on Fluids | 10.1007/s10765-023-03195-1 |
2023-04-17 | The many constrains introduced by the F-gas Regulation and the Kigali Amendment to the Montreal Protocol have resulted in an intense search for alternatives to fluorinated greenhouses gases for air conditioning and refrigeration purposes (Mota-Babiloni A, Makhnatch P, in Int J Refrig 127:101–110, 2021). With respect to the urge of new low-GWP and low-ODP refrigerants, blends composed of hydrofluoroolefins (HFO) are considered promising possible substitutes to hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs) for HVAC&R applications (Sovacool et al., in Renew Sustain Energy Rev 141:110759), but thermophysical properties data for these blends are still scarce (Bell et al., in: J Chem Eng Data, 2021). In the present study, the vapor–liquid equilibrium (VLE) for the binary system (HFO-1243zf + HFO-1234yf), for which just one set of data on the VLE is available to date in literature, has been experimentally studied by means of a vapor recirculation apparatus. The measurements have been performed at isothermal conditions in the range of temperatures between 283.15 K and 323.15 K, while the composition of both the phases in equilibrium has been measured by gas-chromatographic analysis. The experimental VLE data have been correlated by two different equations of state (EoS): the Peng-Robinson (PR) EoS combined with Mathias–Copeman (MC) alpha function and van der Waals (vdW) mixing rules, and the Helmoltz EoS with dedicated binary interaction parameters. Correlated results showed a good agreement with the experimental data for the binary system. | Isothermal (Vapour + Liquid) Equilibrium Measurements and Correlation of the Binary Mixture {3,3,3-Trifluoropropene (HFO-1243zf) + 2,3,3,3-tetrafluoropropene (HFO-1234yf)} at Temperatures from 283.15 K to 323.15 K | 10.1007/s10765-023-03192-4 |
2023-04-17 | Gamma-emitting radionuclide 99m Tc is globally used for the diagnosis of various pathological conditions owing to its ideal single-photon emission computed tomography (SPECT) characteristics. However, the short half-life of 99m Tc ( T 1/2 = 6 h) makes it difficult to store or transport. Thus, the production of 99m Tc is tied to its parent radionuclide 99 Mo ( T 1/2 = 66 h). The major production paths are based on accelerators and research reactors. The reactor process presents the potential for nuclear proliferation owing to its use of highly enriched uranium (HEU). Accelerator-based methods tend to use deuterium–tritium (D–T) neutron sources but are hindered by the high cost of tritium and its challenging operation. In this study, a new 99 Mo production design was developed based on a deuterium–deuterium (D–D) gas dynamic trap fusion neutron source (GDT-FNS) and a subcritical blanket system (SBS) assembly with a low-enriched uranium (LEU) solution. GDT-FNS can provide a relatively high-neutron intensity, which is one of the advantages of 99 Mo production. We provide a Monte Carlo-based neutronics analysis covering the calculation of the subcritical multiplication factor ( k s ) of the SBS, optimization design for the reflector, shielding layer, and 99 Mo production capacity. Other calculations, including the neutron flux and nuclear heating distributions, are also provided for an overall evaluation of the production system. The results demonstrated that the SBS meets the nuclear critical safety design requirement ( k s < 0.97) and maintained a high 99 Mo production capacity. The proposed system can generate approximately 157 Ci 99 Mo for a stable 24 h operation with a neutron intensity of 1 × 10 14 n/s, which can meet 50% of China’s demand in 2025. | Neutronics analysis of a subcritical blanket system driven by a gas dynamic trap-based fusion neutron source for 99Mo production | 10.1007/s41365-023-01206-2 |
2023-04-17 | Background Mesenchymal stem cell (MSC) transplantation therapy is highly investigated for the regenerative repair of cartilage defects. Low-intensity pulsed ultrasound (LIPUS) has the potential to promote chondrogenic differentiation of MSCs. However, its underlying mechanism remains unclear. Here, we investigated the promoting effects and mechanisms underlying LIPUS stimulation on the chondrogenic differentiation of human umbilical cord mesenchymal stem cells (hUC-MSCs) and further evaluated its regenerative application value in articular cartilage defects in rats. Methods LIPUS was applied to stimulate cultured hUC-MSCs and C28/I2 cells in vitro. Immunofluorescence staining, qPCR analysis, and transcriptome sequencing were used to detect mature cartilage-related markers of gene and protein expression for a comprehensive evaluation of differentiation. Injured articular cartilage rat models were established for further hUC-MSC transplantation and LIPUS stimulation in vivo. Histopathology and H&E staining were used to evaluate the repair effects of the injured articular cartilage with LIPUS stimulation. Results The results showed that LIPUS stimulation with specific parameters effectively promoted the expression of mature cartilage-related genes and proteins, inhibited TNF-α gene expression in hUC-MSCs, and exhibited anti-inflammation in C28/I2 cells. In addition, the articular cartilage defects of rats were significantly repaired after hUC-MSC transplantation and LIPUS stimulation. Conclusions Taken together, LIPUS stimulation could realize articular cartilage regeneration based on hUC-MSC transplantation due to the inhibition of the TNF signaling pathway, which is of clinical value for the relief of osteoarthritis. | Low-intensity pulsed ultrasound promotes mesenchymal stem cell transplantation-based articular cartilage regeneration via inhibiting the TNF signaling pathway | 10.1186/s13287-023-03296-6 |
2023-04-14 | Ammonia nitrogen pollutant in aqueous media is difficult to treat, which leads to a deterioration of pristine water ecosystems because of eutrophication and poses significant risks to human health. The efficient treatment of low-concentration ammonia nitrogen wastewater remains difficult. Adsorption is a promising remediation strategy, but suitable adsorbent materials that are abundant, low-cost, environmentally friendly, and efficient remain challenging to find. Recent developments in low-cost adsorbent materials for ammonia nitrogen removal from aqueous solution have been summarized. The physicochemical properties; ammonia removal mechanism; and advantages and disadvantages of representative adsorbent materials, including natural mineral materials, industrial byproducts, biochar, biopolymers, and their modified forms, have been compared. Future perspectives and research directions on the use of inexpensive adsorbents for ammonia nitrogen removal have been provided. | Removal of Ammonia Nitrogen from Aqueous Media with Low-cost Adsorbents: a Review | 10.1007/s11270-023-06285-w |
2023-04-12 | External spacecraft materials play an important role in satellite protection from the harsh space environment.Research has shown that the physical, chemical, and optical properties of matter change continuously as a result of exposure to solar radiation and aggressive chemical species produced in Earth’s upper atmosphere. Thorough knowledge of the material properties evolution throughout a planned mission lifetime helps to improve the reliability of spacecraft. Moreover, the establishment of correlation factors between true space exposure and accelerated space weather experiments at ground facilities enables accurate prediction of on-orbit material performance based on laboratory-based testing. The presented work evaluates the radiation effects of different doses of high-energy electron exposure on surface morphology, optical, and charge transport properties of two materials from the PET family, Melinex ® 454 and Mylar ® M021. | Characterization of polyethylene terephthalate (PET) materials under high-energy electron exposure | 10.1007/s12567-023-00495-y |
2023-04-10 | Background Waxy corn has a short growth cycle and high multiple cropping index. However, after being planted in early spring, late autumn and winter, it is susceptible to low temperature (LT), which reduces the emergence rate and yield. Therefore, it is important to analyze the response mechanism of waxy corn under LT stress. Results All phenotype indexes of waxy corn inbred lines N28 were significantly higher than waxy corn inbred lines N67 under LT. With the increase of LT stress time, all physiological indexes showed an upward trend in N28 and N67. Differentially expressed genes (DEGs) 16,017 and 14,435 were identified in N28 and N67 compared with nongerminated control under LT germination, respectively, and differential metabolites 127 and 93 were detected in N28 and N67, respectively. In addition, the expression level of some genes involved in plant hormones and mitogen activated protein kinase (MAPK) signaling pathways was significantly up-regulated in N28. Compared with N67, flavonoid metabolites were also significantly enriched in N28 under LT germination. Conclusion Under LT stress, the inbred lines N28 was significantly higher than the inbred lines N67 in the phenotypic and physiological indices of cold resistance. Compared with N67, the expression levels of some genes involved in the plant hormones and MAPK pathways were significantly up-regulated in N28, and flavonoid metabolites were also significantly enriched in N28 under LT stress. These genes and metabolites may help N28 to improve cold resistance and may be as potential target genes for cold resistance breeding in waxy corn. | Integrated metabolomics and transcriptomics analysis during seed germination of waxy corn under low temperature stress | 10.1186/s12870-023-04195-x |
2023-04-10 | Microbes in marine sediments detected and counted by direct observation of membrane-filtered sediment samples stained with acridine orange. This technique can still be applied to high-biomass (> 10 5 cells/cm 3 ) sedimentary habitats, such as organic-rich sediments collected in shallow areas near the seafloor. However, to further explore the nutrients and energy turnover under extremely low energy flux conditions, or in habitats that are close to the lower limit of the biosphere, technological breakthroughs have been required to increase the detection sensitivity for microbial life at densities of a few cells/cm 3 of sediment. These technological developments contributed to increasing fundamental information on microbial life at the fringes of the subseafloor biosphere and led to the discovery of revivable microbes in sediments aged up to 101.5 million years old. More recently, chemical detection methods have revealed the existence of spores in the deep biosphere that are impermeable to conventional DNA stains. Previous applications of molecular biology-based approaches have been limited to relatively higher biomass samples, potentially because the cells surviving in these very low energy flux environments have less integrated genomes. Here, I review the contribution and importance of the technological developments that have been made in the study of microbes from the subseafloor biosphere, recent developments of alternative methods to microscopically detect microbial spores and their application to deep subseafloor sediments, and the challenges associated with applying molecular biological approaches to study low-biomass samples. | Accessing the energy-limited and sparsely populated deep biosphere: achievements and ongoing challenges of available technologies | 10.1186/s40645-023-00551-5 |
2023-04-10 | Data from monitoring programs with high spatial resolution but low temporal resolution are often overlooked when assessing temporal trends, as the data structure does not permit the use of established trend analysis methods. However, the data include uniquely detailed information about geographically differentiated temporal trends driven by large-scale influences, such as climate or airborne deposition. In this study, we used geographically weighted regression models, extended with a temporal component, to evaluate linear and nonlinear trends in environmental monitoring data. To improve the results, we tested approaches for station-wise pre-processing of data and for validation of the resulting models. To illustrate the method, we used data on changes in total organic carbon (TOC) obtained in a monitoring program of around 4800 Swedish lakes observed once every 6 years between 2008 and 2021. On applying the methods developed here, we identified nonlinear changes in TOC from consistent negative trends over most of Sweden around 2010 to positive trends during later years in parts of the country. | Temporal trend evaluation in monitoring programs with high spatial resolution and low temporal resolution using geographically weighted regression models | 10.1007/s10661-023-11172-2 |
2023-04-10 | Impurity scattering in junctionless transistors reduces electron velocity in the channel, so the performance of analog/RF at high frequencies degrades. For the first time, this study offers shell-doped channel along with a stacked layer in the source region to optimize analog/RF figure of merits and high-frequency noise performance of heterostructure silicon on insulator-junctionless transistor (HH-SOI-JLT). The suggested idea causes increasing gate control in the maximum current path and decreases impurity scattering. Therefore, current density and mobility of electrons in the channel enhance, and transconductance remarkably increases. The proposed structure named shell-doped channel HH-SOI-JLT (SDCh-HH-SOI-JLT) attains g mmax = 25 mS/µm (transconductance), $$f_{{\text{T}}}$$ f T = 3.5 THz (unity gain cut-off frequency), NF min = 0.07 dB (minimum noise figure), and Gma = 26.8 dB (maximum available gain). The g mmax , $$f_{{\text{T}}}$$ f T , NF min , and Gma are modified by 150%, 110%, 100%, and 23% compared to HH-SOI-JLT, respectively. A low-noise amplifier (LNA) using SDCh-HH-SOI-JLT designed for F-Band 6G. An s2p model is developed for the proposed device and incorporated into the ADS software in circuit simulation. The LNA with NF < 0.3 dB and nearly flat S 21 (≈ 15 dB) were achieved. Thus, the SDCh-HH-SOI-JLT is considered a reasonable candidate for 6G mobile communication systems and radars. Graphical abstract | Low-noise Si/Si0.5Ge0.5 SOI junctionless TeraFET for designing sub-0.5 dB ultra-broadband LNA in 6G applications | 10.1007/s00339-023-06546-9 |
2023-04-07 | In the last decades, the industry of HVAC&R has faced continuous changes trying to identify environmentally friendly refrigerants for the numerous applications of the sector. However, the amount of low GWP fluids still available as potential refrigerants is limited to some natural fluids and, among synthetic chemicals, to hydrofluoroolefins (HFO). The knowledge of the thermophysical properties of these compounds and the evaluation of their energy efficiency in experimental apparatuses is essential to properly address the selection of the most suitable fluids. However, regarding the wide majority of HFOs, the information on the thermophysical properties, especially for the blends, are still scarce and require further research. In this work, an analysis of the possible substitutes and the available experimental data sets on their thermophysical properties was carried out to find out for which fluids further studies are needed to obtain an accurate representation of their thermophysical properties. Specifically, for 21 pure refrigerants, an overview of the thermodynamic ( critical point, p sat , PVT , heat capacity and speed of sound) and transport properties ( λ, μ, σ ) data published in the peer reviewed literature was provided. In addition, a more comprehensive analysis was carried out for four fluids (R1243zf, R1233zd(E), R1336mzz(Z), and R1224yd(Z)), for which major efforts have been made in the last 4 years to investigate the above thermophysical properties. Although an increasing amount of data sets on thermophysical properties have been compiled in recent years, the present study indicates that research efforts are still needed, especially on transport properties, as only 4 of the fluids of interest for the present research have been fully investigated (R1234yf, R1234ze(E), R1233zd(E), R1243zf), while other 4 (R1234ze(Z), R1336mzz(Z), R1224yd(Z), R1336mzz(E)) have been almost completely characterised. | Thermophysical Properties of Low GWP Refrigerants: An Update | 10.1007/s10765-023-03191-5 |
2023-04-07 | Extremely low visibility affects aviation services. Aviation services need accurate fog and low-visibility predictions for airport operations. Fog and low-visibility forecasting are difficult even with modern numerical weather prediction models and guiding systems. Limitations in comprehending the micro-scale processes that lead to fog formation, intensification, onset, and dissipation complicate fog prediction. This article predicts low visibility for Jay Prakash Narayan International Airport (JPNI), Patna, India, using a historical synoptic dataset. The proposed machine learning (ML) approaches optimize three meta-algorithm approaches: boosting (which reduces variances), bagging (which reduces bias), and stacking (which improves predictive forces). The ML approaches optimize the best prediction algorithms (at level 0) for fog (surface visibility ≤ 1000 m) and dense fog (surface visibility ≤ 200 m), and the suggested ensemble models at level 1 (an ensemble of level 0 ML approaches) deliver the highest performance and stability in prediction output. All time series perform well with the specified model (6-h to 1-h lead time for any combination of observed historical datasets). Airport management, planning, and decision-making rely on high reliability. Because it works well and is reliable, the proposed approaches can be used at other airports in India's Indo-Gangetic Plain. If low visibility can be predicted with a high level of accuracy, airports could run more efficiently. Proposed ensemble ML approach optimize bagging, boosting, and stacking algorithms to reliably predict low visibility. It fills the gap in predicting low visibility in the Indo-Gangetic Plain (IGP), where fog is a perennial issue in winter. | Early warning of low visibility using the ensembling of machine learning approaches for aviation services at Jay Prakash Narayan International (JPNI) Airport Patna | 10.1007/s42452-023-05350-7 |
2023-04-07 | With the rise of deep learning, spoken language understanding (SLU) for command-and-control applications such as a voice-controlled virtual assistant can offer reliable hands-free operation to physically disabled individuals. However, due to data scarcity, it is still a challenge to process dysarthric speech. Pre-training (part of) the SLU model with supervised automatic speech recognition (ASR) targets or with self-supervised learning (SSL) may help to overcome a lack of data, but no research has shown which pre-training strategy performs better for SLU on dysarthric speech and to which extent the SLU task benefits from knowledge transfer from pre-training with dysarthric acoustic tasks. This work aims to compare different mono- or cross-lingual pre-training ( supervised and unsupervised ) methodologies and quantitatively investigates the benefits of pre-training for SLU tasks on Dutch dysarthric speech. The designed SLU systems consist of a pre-trained speech representations encoder and a SLU decoder to map encoded features to intents. Four types of pre-trained encoders, a mono-lingual time-delay neural network (TDNN) acoustic model, a mono-lingual transformer acoustic model, a cross-lingual transformer acoustic model (Whisper), and a cross-lingual SSL Wav2Vec2.0 model (XLSR-53), are evaluated complemented with three types of SLU decoders: non-negative matrix factorization (NMF), capsule networks, and long short-term memory (LSTM) networks. The acoustic analysis of the four pre-trained encoders are tested on Dutch dysarthric home-automation data with word error rate (WER) results to investigate the correlations of the dysarthric acoustic task (ASR) and the semantic task (SLU). By introducing the intelligibility score (IS) as a metric of the impairment severity, this paper further quantitatively analyzes dysarthria-severity-dependent models for SLU tasks. | Benefits of pre-trained mono- and cross-lingual speech representations for spoken language understanding of Dutch dysarthric speech | 10.1186/s13636-023-00280-z |
2023-04-06 | The storage of liquified natural gas in concrete tanks is important for the adjustment of imbalance between consumption and supply. The mechanical properties of concrete under different water saturation and low temperature conditions are investigated from the uniaxial compression and splitting tensile strength tests. Both the elastic strain and peak strain at failure increase with the decrease of temperature in the compressive strength tests. The compressive and tensile strengths decrease with the increase of water content at 20 °C due to the water softening effects, while they increase with the water content at subzero temperatures resulting from the ice filling and binding effects. The elastic modulus follows the same trend with that of the compressive strength. Significant increases in the strength and brittleness index occur between − 30 and − 90 °C as the water in the vast nanopores is frozen. The freeze–thaw cycle at − 30 °C induces the increase in the number of larger pores, while the large pores are collapsed or filled after one freeze–thaw cycle at − 90 °C and − 180 °C due to the inward deformation resulting from the inconsistent contraction and expansion deformations between different particles. Our proposed prediction models show better fitting for the compressive and tensile strengths. | Mechanical properties of concrete under different water content and low temperature conditions | 10.1617/s11527-023-02152-6 |
2023-04-05 | Background Low temperature (LT) stress is one of the major environmental stress factors affecting the growth and yield of maize ( Zea mays L.). Hence, it is important to unravel the molecular mechanisms behind LT stress tolerance to improve molecular breeding in LT tolerant genotypes. In the present study, two maize genotypes viz. Gurez local from Kashmir Himalaya and tropical grown GM6, were dissected for their LT stress response in terms of accumulation of differentially regulated proteins (DRPs). Leaf proteome analysis at three-leaf stage of maize seedlings subjected to LT stress of 6 °C for a total of 12 h duration was performed using two dimensional gel electrophoresis (2D-PAGE) followed by subsequent identification of the proteins involved. Results After MALDI-TOF (Matrix-assisted laser desorption/ionization-time of flight) and bioinformatics analysis, 19 proteins were successfully identified in Gurez local, while as 10 proteins were found to get successful identification in GM6. The interesting observations from the present investigation is the identification of three novel proteins viz. threonine dehydratase biosynthetic chloroplastic, thylakoidal processing peptidase 1 chloroplastic, and nodulin-like protein, whose role in abiotic stress tolerance, in general, and LT stress, in particular, has not been reported so far. It is important to highlight here that most of LT responsive proteins including the three novel proteins were identified from Gurez local only, owing to its exceptional LT tolerance. From the protein profiles, obtained in both genotypes immediately after LT stress perception, it was inferred that stress responsive protein accumulation and their expression fashion help the Gurez local in seedling establishment and withstand unfavorable conditions as compared to GM6. This was inferred from the findings of pathway enrichment analysis like regulation of seed growth, timing of floral transition, lipid glycosylation, and aspartate family amino acid catabolic processes, besides other key stress defense mechanisms. However, in GM6, metabolic pathways enriched were found to be involved in more general processes including cell cycle DNA replication and regulation of phenylpropanoid metabolism. Furthermore, majority of the qRT-PCR results of the selected proteins demonstrated positive correlation between protein levels and transcript abundance, thereby strengthening our findings. Conclusions In conclusion, our findings reported majority of the identified proteins in Gurez local exhibiting up-regulated pattern under LT stress as compared to GM6. Furthermore, three novel proteins induced by LT stress were found in Gurez local, requiring further functional validation. Therefore, our results offer more insights for elucidating the molecular networks mediating LT stress tolerance in maize. | Comparative protein analysis of two maize genotypes with contrasting tolerance to low temperature | 10.1186/s12870-023-04198-8 |
2023-04-05 | Background Optimal shaping of contextual factors (CFs) during clinical encounters may be associated with analgesic responses in treatments for musculoskeletal pain. These CFs (i.e., the patient-practitioner relationship, patient’s and practitioner’s beliefs/characteristics, treatment characteristics, and environment) have not been widely evaluated by musculoskeletal practitioners. Understanding their views has the potential to improve treatment quality and effectiveness. Drawing on a panel of United Kingdom practitioners’ expertise, this study aimed to investigate their perceptions of CFs during the management of patients presenting with chronic low back pain (LBP). Methods A modified two-round online Delphi-consensus survey was conducted to measure the extent of panel agreement regarding the perceived acceptability and influence of five main types of CFs during clinical management of patients with chronic LBP. Qualified musculoskeletal practitioners in the United Kingdom providing regular treatment for patients with chronic LBP were invited to take part. Results The successive Delphi rounds included 39 and 23 panellists with an average of 19.9 and 21.3 years of clinical experience respectively. The panel demonstrated a high degree of consensus regarding approaches to enhance the patient-practitioner relationship (18/19 statements); leverage their own characteristics/beliefs (10/11 statements); modify the patient’s beliefs and consider patient’s characteristics (21/25 statements) to influence patient outcomes during chronic LBP rehabilitation. There was a lower degree of consensus regarding the influence and use of approaches related to the treatment characteristics (6/12 statements) and treatment environment (3/7 statements), and these CFs were viewed as the least important. The patient-practitioner relationship was rated as the most important CF, although the panel were not entirely confident in managing a range of patients’ cognitive and emotional needs. Conclusion This Delphi study provides initial insights regarding a panel of musculoskeletal practitioners’ attitudes towards CFs during chronic LBP rehabilitation in the United Kingdom. All five CF domains were perceived as capable of influencing patient outcomes, with the patient-practitioner relationship being perceived as the most important CF during routine clinical practice. Musculoskeletal practitioners may require further training to enhance their proficiency and confidence in applying essential psychosocial skills to address the complex needs of patients with chronic LBP. | Musculoskeletal practitioners’ perceptions of contextual factors that may influence chronic low back pain outcomes: a modified Delphi study | 10.1186/s12998-023-00482-4 |
2023-04-04 | The deep underground environment has complex geological conditions, which result in cement-based materials under the coupling conditions of high crustal stress, high pressure, and high temperature for the long-term. Thus, the mechanism of water transport is more complicated and often accelerates the deterioration of cement-based materials. In this study, the rules of water transport in mortar with an ultra-low w/b ratio under the coupling conditions of osmotic pressure, confining pressure, and temperature were systemically investigated based on a novel experimental device and low-field NMR technology. Experimental results showed that the saturation of the pore structure and penetration depth of mortar increased rapidly in the early stage (the first 10 min), and the water was mainly filled in nano-scale pores. Low-field NMR imaging technology could be applied to the visualization study of water transport in WPC mortar. With the increase of osmotic pressure and ambient temperature, the penetration rate of water in mortar was significantly increased, and the water was preferentially filled in nano-scale pores with pore sizes less than approximately 200 nm. The increase of confining pressure could improve the permeability of mortar to a certain extent due to the decrease in the penetration rate of water. For water transport in mortar with an ultra-low w/b ratio, the descending order of influence degree of different factors was osmotic pressure, confining pressure, and temperature. | In situ visualization of water transport in cement mortar with an ultra-low w/b ratio under the coupling conditions of osmotic pressure, confining pressure, and temperature | 10.1617/s11527-023-02145-5 |
2023-04-04 | Abstract Orange peel is a fruit-based biomass produced in huge quantities worldwide, requiring an appropriate management strategy to meet the waste-to-wealth approach. In the current study, this agricultural waste was used (as an adsorbent) to treat dye-laden wastewater, followed by its regeneration and recyclability for dual biogas and biochar production. An adsorbent material was prepared by mixing orange peel powder (OPP) with biochar (1:1, w/w) and used to remove various pollutants from textile wastewater (TWW) within 30 min. This adsorption system achieved chemical oxygen demand (COD), total dissolved solids (TDS), turbidity, and color removal efficiencies of 38.56±1.73%, 29.31±1.25%, 91.92±4.75%, and 74.81±3.96%, respectively. The spent adsorbent was cleaned and mixed with cow dung (as inoculum) to generate biogas via anaerobic co-digestion. This system maintained a bio-CH 4 of 411.5±21.7 mL/g volatile solids (VS), equivalent to 14.3±1.1% of COD initial . Because the digestate of the co-digestion process contained volatile suspended solids (VSS), with a VSS/COD initial percentage of 45.2±3.2%, it was efficiently pyrolyzed to obtain biochar. The adsorption/co-digestion/pyrolysis combined system revealed a financially feasible scenario, with a payback period of 7.5 years. The study outputs would fulfill various sustainable development goals (SDGs) related to waste minimization, environmental protection, and affordable energy supply. Graphical abstract | Utilizing orange peel waste biomass in textile wastewater treatment and its recyclability for dual biogas and biochar production: a techno-economic sustainable approach | 10.1007/s13399-023-04111-1 |
2023-04-04 | Background Sacroiliac (SI) joint dysfunction is a common source of back pain. Recent evidence from different parts of the world suggest that cooled radiofrequency ablation of sacral nerves supplying the SI joints has superior pain alleviating properties than currently available treatment options for SI joint dysfunction. Patients and methods After obtaining institutional review board approval, the medical records of 81 patients who underwent cooled radiofrequency ablation in a single institution and by a single surgeon were analyzed retrospectively. The recurrence of pain, progression to fusion and functional outcomes were noted. The patients were operated on between June 2020 and December 2021, they include 59 females and 22 males, the average age was 55.4 ± 17.3. Follow up was at least 6 months postoperative. Results 22 of the patients had previously underwent lumbar fusions. Follow up period ranged from 6 to 18 months. After radiofrequency ablation, 7 patients progressed to fusions, and 6 patients had to have the procedure done again to relieve their pain. Student t-test was used to compare between preoperative and postoperative values of NPRS (numerical pain rating score) and ODI (Oswestry disability index). It showed significance with P-value < 0.001 in both. Conclusions Sacroiliac joint radiofrequency ablation is a good option in the treatment of SI joint pain showing good results in the short term follow up period. It is a simple procedure that can be done in less than 30 min and is capable of providing significant pain relief for patients with sacroiliac joint dysfunction. | Cooled radiofrequency ablation of the sacroiliac joint a retrospective case series | 10.1186/s12891-023-06344-7 |
2023-04-03 | With the development of new technologies, particularly Internet of Things (IoT), there has been an increase in the deployment of low-cost air quality monitoring systems. Compared to traditional robust monitoring stations, these systems provide real-time information with higher spatio-temporal resolution. These systems use inexpensive and low-cost sensors, with lower accuracy as compared to robust systems. This fact has raised some concern regarding the quality of the data gathered by the IoT systems, which may compromise the performance of the environmental models. Considering the relevance of the data quality in this scenario, this paper presents a study of the data quality associated with IoT-based air quality monitoring systems. Following a systematic mapping method, and based on existing guidelines to assess data quality in these systems, we have identified the main Data Quality (DQ) dimensions and the corresponding DQ enhancement techniques. After analyzing more than 70 papers, we found that the most common DQ dimensions targeted by the different works are accuracy and precision, which are enhanced by the use of different calibration techniques. Based on our findings, we present a discussion on the challenges that must be addressed in order to improve data quality in IoT-based air quality monitoring systems. | Data Quality in IoT-Based Air Quality Monitoring Systems: a Systematic Mapping Study | 10.1007/s11270-023-06127-9 |
2023-04-03 | Background Chronic neck and back pain are among the most commonly encountered health problems in neurosurgical practice. Many cases fail prolonged pharmacological and physical therapy and are not proper candidates for surgical interventions, or had refused proposed surgical treatment. Objective To provide an informative critical summary of the literature about the topic of interventional management of axial neck and low back pain and highlighting the new trends and pieces of evidence. Methods The English literature published over the last two decades was reviewed by the author for recent and relevant data about the principles of interventional management of chronic neck and low back pain. A PubMed search was performed through phrase searching and combined searching using Boolean operators. The articles thought to be most relevant to the study aim and the neurosurgeons’ practice were extracted. Results Neck and low back pain continue to be among the most common musculoskeletal health problems and the most common cause of disability worldwide. A detailed understanding of relevant spine anatomy is crucial for interventionists who should deal with the concept of “functional spine unit” with multiple potential pain generators. Chronic spinal pain is best managed through a dedicated multidisciplinary team in well-equipped healthcare facilities. An algorithmic approach for the diagnosis and management of spinal pain is the mainstay of providing the best patient care and should be based on the commonality and treatability of pain generators, values of patients and available resources. Conclusion Management of chronic neck and back pain can represent a clinical dilemma due to the multiplicity of pain generators that may coexist in the same individual resulting in a complex type and pattern of pain. Approach to these patients requires contributions from the members of a multidisciplinary team, implementing a standardized approach in a well-equipped healthcare facility. | Interventional non-operative management of low back and neck pain | 10.1186/s41984-023-00189-x |
2023-04-02 | Materials with high hardness, strength or plasticity have been widely used in the fields of aviation, aerospace, and military, among others. However, the poor machinability of these materials leads to large cutting forces, high cutting temperatures, serious tool wear, and chip adhesion, which affect machining quality. Low-temperature plasma contains a variety of active particles and can effectively adjust material properties, including hardness, strength, ductility, and wettability, significantly improving material machinability. In this paper, we first discuss the mechanisms and applications of low-temperature plasma-assisted machining. After introducing the characteristics, classifications, and action mechanisms of the low-temperature plasma, we describe the effects of the low-temperature plasma on different machining processes of various difficult-to-cut materials. The low-temperature plasma can be classified as hot plasma and cold plasma according to the different equilibrium states. Hot plasma improves material machinability via the thermal softening effect induced by the high temperature, whereas the main mechanisms of the cold plasma can be summarized as chemical reactions to reduce material hardness, the hydrophilization effect to improve surface wettability, and the Rehbinder effect to promote fracture. In addition, hybrid machining methods combining the merits of the low-temperature plasma and other energy fields like ultrasonic vibration, liquid nitrogen, and minimum quantity lubrication are also described and analyzed. Finally, the promising development trends of low-temperature plasma-assisted machining are presented, which include more precise control of the heat-affected zone in hot plasma-assisted machining, cold plasma-assisted polishing of metal materials, and further investigations on the reaction mechanisms between the cold plasma and other materials. | A review of low-temperature plasma-assisted machining: from mechanism to application | 10.1007/s11465-022-0734-y |
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