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2023-06-01 | CUPID is a next-generation tonne-scale bolometric neutrinoless double beta decay experiment that will probe the Majorana nature of neutrinos and discover lepton number violation in case of observation of this singular process. CUPID will be built on experience, expertise and lessons learned in CUORE and will be installed in the current CUORE infra-structure in the Gran Sasso underground laboratory. The CUPID detector technology, successfully tested in the CUPID-Mo experiment, is based on scintillating bolometers of Li $$_2$$ 2 MoO $$_4$$ 4 enriched in the isotope of interest $$^{100}$$ 100 Mo. In order to achieve its ambitious science goals, the CUPID collaboration aims to reduce the backgrounds in the region of interest by a factor 100 with respect to CUORE. This performance will be achieved by introducing the high efficient $$\alpha$$ α / $$\beta$$ β discrimination demonstrated by the CUPID-0 and CUPID-Mo experiments, and using a high transition energy double beta decay nucleus such as $$^{100}$$ 100 Mo to minimize the impact of the gamma background. CUPID will consist of about 1500 hybrid heat-light detectors for a total isotope mass of 250 kg. The CUPID scientific reach is supported by a detailed and safe background model based on CUORE, CUPID-Mo and CUPID-0 results. The required performances have already been demonstrated and will be presented. | CUPID: The Next-Generation Neutrinoless Double Beta Decay Experiment | 10.1007/s10909-022-02909-3 |
2023-06-01 | Abstract The introduction of biodegradable additives into the matrix of synthetic polymers allows one to develop environmentally friendly materials with increased biodegradability. In this paper, composite films based on low-density polyethylene with natural rubber at a content of 10–30 wt % are studied. A mycological test with fungi and field test of soil have shown that the composite with the addition of natural rubber in the amount of 30 wt % is the most biodegradable (mass loss is comprised 7.2 wt % in 90 days). In the experiment on biodegradation in soil, the most intensive development of filamentous fungi has been recorded in field tests. A study has been also conducted of compositions with the addition of polylactide, which belongs to biodegradable polymers. When exposed to soil, a different character of the destruction of the material is noted, mainly due to hydrolysis. Thus, depending on the nature of biodegradable polymer additives, operational characteristics and biodegradation in the soil change. | The Effect of the Nature of Biodegradable Components on Biodegradability of Composites Based on Polyethylene | 10.1134/S1995421223020466 |
2023-06-01 | The permeability of a C 60 fullerite in a simple cubic phase for natural gas components is investigated. The classical molecular dynamics methods and the Monte Carlo method are used to study the physical effects appearing in the case where the particles pass through a thin layer of a crystalline fullerite. A discrete model of atom-atom interactions is used to take into account the mutual influence of the elements of the system (fullerenes and penetrating particles). The influence of the incoming particle velocities on the permeability is shown, and a characteristic factor affecting the permeability of the crystalline system is determined. | Selective Property of Ultrathin Layers of a Low-temperature Fullerite | 10.1007/s11182-023-02931-2 |
2023-06-01 | Anti-reflective (AR) coatings are used in various optical products, such as lenses, filters, and transparent conductive films. High-performance multilayer AR coatings can be achieved by reducing the refractive index of the top layer. Preventing light scattering by forming finely structured film is also important for a high-performance antireflection film. In this study, porous SiO 2 thin films with ultralow refractive indices were prepared using a simple sol–gel method. A high-quality porous SiO 2 thin film with an ultralow refractive index of 1.17 bearing a fine porous structure was fabricated by carefully selecting the solvent and base species. Observation and simulation of the film structure revealed the factors responsible for the low scattering of light and the ultralow refractive index exhibited by the film. Hydrophobic treatment of the film was conducted to reduce the fluctuation of optical performance caused by changes in the refractive index owing to the water adsorbed. Therefore, porous SiO 2 thin films can be used in the lenses and filters of various optical instruments. Graphical abstract A transparent film with low refractive index was obtained. The film has porous structure, consisting of silica particles of a few nm in size. The pores size was found to be a few nm by image analysis. Thin films with low refractive index and low scattering for optics were successfully prepared by a simple sol–gel method. Ultralow refractive index porous silica film, n = 1.17, was prepared using a simple sol–gel method. Decreasing of light scattering was achieved by choice of basic catalyst and solvent. Hydrophobic treatment successfully reduced the fluctuation of the refractive index of the film. | Fabrication of a porous SiO2 thin film with an ultralow refractive index for anti-reflective coatings | 10.1007/s10971-023-06108-8 |
2023-06-01 | The Follow-up X-ray Telescope (FXT) is one of the key payloads onboard EP. It is a Wolter-I type X-ray focusing telescope equipped with two telescope modules (focal length 1.6 m), with a total effective area of ~ 600 cm2 at 1.25 keV and an energy range of 0.3–10 keV. FXT is mainly composed of an X-ray focusing mirror assembly (MA) and a camera assembly with a PNCCD detector module. The two FXT modules are completely independent from each other, thus avoiding a single point failure. We completed the internal composites of FXT structural design, which meets the function and performance requirements of mechanical, thermal, contamination control and X-ray optics. The FXT passed successfully the mechanical, thermal qualification level tests on the spacecraft platform in the phase C. | The structural design and thermo-mechanical performance of the FXT for the EP mission | 10.1007/s10686-023-09889-6 |
2023-06-01 | Synthetic single crystals of K[(Cu II ,Mn II ,Mn III ) 2 (TeO 3 ) 3 ]·2H 2 O were obtained from an overconcentrated alkaline aqueous solution in the system K 2 O-MnO-CuO-TeO 2 under hydrothermal conditions at T ≤ 220 °C. Subeuhedral single crystals have been investigated by means of single-crystal X-ray diffraction. The crystal structure of this new zemannite-type representative adopts a monoclinic twofold superstructure. The doubling of the unit-cell volume is accompanied by a hexagonal-to-monoclinic symmetry reduction, resulting in threefold twinning with individual crystal domains following the space group symmetry P 2 1 . Refinements of site-occupation factors and the evaluation of bond valences suggest a distribution of di- and trivalent cations at the octahedrally coordinated M sites with a ratio (Cu II + Mn II ):Mn III approximating 1:1. Based on arguments about the cation sizes and the individual bond valence sums, a distribution of Cu II 1– x Mn III x and Mn II x Mn III 1– x at each two of the four M sites can be assumed with x between ~ 0.14 and ~ 0.50. The K + cations and H 2 O molecules inside the channels are located off the central channel axis. In contrast to most other known zemannite-type phases, the extra-framework atoms show full occupancies and are not disordered. The distribution of the channel contents supports the anisotropic deformation of the surrounding framework, which follows the local symmetry reduction as required for the Jahn-Teller distortion of the octahedrally coordinated M sites within the framework. The arrangement of the deformed channels can be understood as the origin of the existing superstructure. | K[(CuII,MnII,MnIII)2(TeO3)3]∙2H2O, the first zemannite-type structure based on a Jahn-Teller-distorted framework | 10.1007/s00710-022-00808-9 |
2023-06-01 | Potassium metal battery is a promising alternative to Li-ion battery for large-scale energy storage due to the abundant potassium resources and high energy density. However, it suffers from rapid capacity fading and safety issues due to the uncontrolled dendrite growth. Herein, we design a fluorine-free ultra-low concentration electrolyte (ULCE) with the super bulky [BPh 4 ] − anions for stable potassium metal battery. In this special electrolyte, the migration rate of K + in the electrolyte is about six times faster than that of the [BPh 4 ] − anions because of the super bulky structure of the [BPh 4 ] − anions, thus resulting in a high K + transference number of 0.76. This high transference number can effectively make up for the deficiency of K + in ULCE for ensuring the normal operation of the potassium metal battery. In addition, the improved transference number can also promote the uniform distribution of K + flux on the surface of the K metal anode, resulting in uniform K deposition. As a result, this electrolyte achieves a high K plating/stripping Coulombic efficiency of 92.6% over 200 cycles and a stable discharging/charging for 100 cycles under the full battery configuration (K used as the anode and perylene-3,4,9,10-tetracarboxylic dianhydride used as the cathode). | An ultra-low concentration electrolyte with fluorine-free bulky anions for stable potassium metal batteries | 10.1007/s12274-022-4961-7 |
2023-06-01 | The lacustrine source rocks of the upper member of the lower Ganchaigou Formation ( $${\text{E}}_{3}^{2}$$ E 3 2 ) in the Yingxi area are considered to be important source rocks in the Qaidam Basin in northwestern China. In this study, we investigated the organic geochemical characteristics of the source rocks by selecting representative samples of the Eocene lacustrine succession spanning 200 m. The results show that the source rock quality is at a fair to good level, and the organic matter (OM) is in the immature–low-maturity stage. The OM originated from plankton/algae and bacteria, with a fluctuating input of terrigenous plants. The source rocks were deposited in a reducing saline-hypersaline environment, with water-column stratification associated with a variable chemocline related to a fluctuating salinity. The vertical variability of the OM abundance is accompanied by simultaneous changes in the source of the OM and the lake water environment parameters, which is caused by the oscillations between drier and wetter conditions in inland Asia in the Late Eocene. The drier periods had strong evaporation and low fluvial input, which facilitated the formation of widespread water anoxia and enhanced OM preservation, while the wetter periods had higher fluvial input and moderate OM preservation conditions because the higher sedimentation rate led to a strong terrestrial dilution effect, which in turn limited the accumulation of OM. | Organic geochemical characteristics and organic matter accumulation of the Eocene lacustrine source rock in the Yingxi area, Western Qaidam Basin, China | 10.1007/s00531-023-02297-3 |
2023-06-01 | The aim of this paper is to demonstrate the efficiency of a low-cost and sustainable timber-based energy dissipation system with recentering ability, which can be used as a seismic isolation system or a tuned mass damper for the seismic protection of structures in developing or developed countries. The system, defined as Dovetail with SPrings (Dove-SP), utilizes the attractive properties of timber to store CO 2 , thus reducing the carbon footprint of the existing energy dissipation systems: It comprises two timber slabs that are designed to slide against each other in a motion that is restrained by a dovetail sliding joint. Two sliding interfaces that allow this sliding motion at an attractively low friction coefficient are experimentally investigated: A PVC sand-wich (PVC-s) sliding interface, comprising a thin layer of sand that is sand-wiched between two PVC layers and a timber sand-wich sliding interface consisting of a thin layer of sand encapsulated between two beech timber surfaces. A set of low-cost steel springs is designed and installed on both sides of the dovetail joint to recenter the structure back to its original position after the end of an earthquake ground motion excitation. A novel, low-cost and deformable wood material fabricated from delignified balsa wood is used to reduce the pounding effects before the activation of the steel springs. The seismic behavior and the recentering ability of the novel timber-based energy dissipation system subjected to an ensemble of recorded earthquake ground motion excitations was experimentally investigated through a large-scale shaking table investigation at ETH Zurich. | Shaking table investigation of a low-cost and sustainable timber-based energy dissipation system with recentering ability | 10.1007/s10518-022-01464-2 |
2023-06-01 | Abstract The effects of a low-frequency pulsed magnetic field (1.5 Hz) and low-intensity laser radiation (0.3 and 0.7 W) on the activity of intracellular oxidoreductases of micromycetes, Penicillium cyclopium , Aspergillus niger , and Alternaria alternata , which are active agents of biodegradation of industrial materials, were studied. The studied physical factors had dose-dependent effects on the activity of fungal intracellular oxidoreductases (catalase and peroxidase); both an increase and a decrease in enzyme activity were observed. An increase in the activity of enzymes can contribute to the manifestation of the adaptive properties of fungi to the action of such physical factors as low-intensity laser radiation and magnetic field. A decrease in the activity of intracellular catalase and peroxidase under the action of these factors may inhibit the vital activity of microorganisms. | Changes in the Activity of Micromycete Intracellular Oxidoreductases under the Action of a Low-Frequency Pulsed Magnetic Field and Low-Intensity Laser Radiation | 10.1134/S0006350923030132 |
2023-06-01 | To achieve more efficient and accurate measurement of low- and intermediate-level radioactive waste (LILW), a room-temperature semiconductor detector CdZnTe (CZT) can be used to replace the high-purity germanium detector. The traditional method cannot identify nuclides since the energy resolution of CZT detectors is poor, and the spectrum have more overlapping peaks, compared with HPGe detectors. Therefore, in this study, we proposed a gamma spectrum analysis method based on an intelligent dynamic library. Simulation spectrum experiment and standard-source spectrum experiment achieved LILW all-nuclide quantitative analysis based on a CZT detector for the first time globally. | Research on the CdZnTe γ spectrum analysis based on an intelligent dynamic library | 10.1007/s10967-023-08858-9 |
2023-06-01 | In this paper, an interface circuit for far-distance energy harvesting from magnetic field of overhead lines is presented. Due to the specific conditions of this type of energy harvesting, such as low available power, low induced voltage in the energy harvester coil, and change of energy harvester impedance, a direct AC/DC switching converter should be used. A maximum power point tracking solution is also necessary to guarantee impedance matching at different operation points. Since the harvested power is in the range of a hundred micro-watts, the power usage of the control circuitry is of significant importance and conventional design approaches based on microcontrollers and FPGAs which require ADCs, DACs and digital signal processing cannot be applied here. The proposed processing circuitry presented in this paper uses three feedback loops to perform the harvesting and energy transfer control. Only low-power comparators and basic digital gates are used as signal-processing elements to limit the power dissipation of the designed control blocks. The impedance matching inner loop samples the H-bridge voltage drop to extract the output load current and perform PWM impedance matching while transferring a rectified current to the output capacitor. Another inner feedback loop is used at the output capacitor using two-level comparison to regulate the output voltage. For maximum power point tracking an outer feedback loop samples the output voltage transfer rate and using a 50 Hz reference generator, adjusts the parameters of the impedance matching circuit of the first inner loop. With the proposed approach, in addition to converting the AC input power to a DC voltage, the output load is regulated at a fixed potential and using the MPPT control loop, the maximum power available from the coil is delivered to the output with relatively low dissipation. The proposed circuit is evaluated using a 0.18 μm standard CMOS technology and operates as a self-powered circuit without an external power source. Based on the obtained results, the efficiency of the proposed circuit at 119 µW input power is about 92.4%, and the MPPT efficiency is about 95%, which is suitable for low-power applications. | An energy-efficient CMOS interface circuit with maximum power point tracking and power management capabilities for self-powered sensor node applications using 50/60 Hz transmission line magnetic field harvesters | 10.1007/s00202-023-01740-7 |
2023-06-01 | An experimental investigation is made for evaluating the long-term creep behavior of a compacted clay under low confining pressure (from 12 to 50 kPa). Specimens compacted at the natural dry density and natural water content were first subjected to consolidated undrained shear tests to determine the shear strength. Undrained triaxial creep tests were thereafter conducted to study the axial strain versus time relationships under different deviatoric stress levels which were determined referencing the shear strength. Mercury intrusion porosimetry tests were performed to track the evolution of the microstructure during the undrained creep. Testing results showed that (i) the diameter of the dominant pores within the clay increases under low confining pressure but decreases under higher confining pressure after undrained creep, (ii) all axial strain versus time relationships show attenuated or transitional characteristics and no creep rupture occurs, and (iii) the proportion of total progressive axial strain in the total axial strain increases with the increasing deviatoric stress level and decreasing confining pressure. Three approaches were used to predict the measured axial strain versus time relationships under low confining pressures. Good agreements have been achieved between the predictions and measurements obtained in this study, which confirms the validity of the proposed approaches. | Undrained creep behavior of a compacted clay under low confining pressure | 10.1007/s11043-022-09582-9 |
2023-06-01 | In order to study the influence of different vascular stenosis rates and stent-to-artery ratios on the fatigue strength and reliability of lower limb arterial stents, numerical simulation was conducted for the fatigue strength of complete SE stents under pulsating loads using a finite element method. Then, fracture mechanics and conditional probability theory were adopted for mathematical modeling, whereby analyzing the crack growth rate and reliability with stents of different thickness (0.12, 0.15, and 0.18 mm) at different vascular stenosis rates (30, 50, and 70%) and stent-to-artery ratios (80, 85, and 90%). The study found: all three stents of different thickness failed to meet 10-year service life at three vascular stenosis rates; all three stents of different thickness met 10-year service life at three stent-to-artery ratios. With increased vascular stenosis rate, the elastic strain of stents was increased, while the fatigue strength was decreased; with increased stent-to-artery ratio, the elastic strain of the stent was increased, while the reliability of the stent was reduced. After the stent with an initial crack was implanted into the vessel, the crack length underwent non-linear growth with increased pulsating cyclic loads. When the pulsating load reached 3 × 10 8 , the growth rate of the crack on the stent surface increased exponentially, leading to a rapid decrease in reliability. Vascular stenosis rate, stent release ratio, and support thickness have significant effects on crack length propagation rate and reliability. Determining the influence of vascular stenosis rate and stent-to-artery ratio on the fatigue strength and reliability of stents provides a valuable reference for evaluating the fracture failure rate and safety of stents. | Analysis of Fatigue Strength and Reliability of Lower Limb Arterial Stent at Different Vascular Stenosis Rates and Stent-to-Artery Ratios | 10.1007/s10439-023-03165-6 |
2023-06-01 | Arsenic (As) contamination of the bodies of water, especially drinking water sources, is a crucial environmental issue with direct implications on human health. In developing countries such as Pakistan, many inhabitants are exposed to contaminated drinking water. For several decades, there has been a search for cost-effective and efficient methods to treat As-contaminated water. Bentonite clays are a cheap potential candidate that could be effective in decontaminating As-polluted drinking water on an industrial scale. Four bentonite deposits in Khyber Pakhtunkhwa, Pakistan, were investigated in detail for their mineralogical composition and potential use as As adsorbents. It was hypothesized that smectite-rich local bentonite clays are effective in decontaminating As-contaminated drinking water. Thus, the specific objective was to evaluate the potential of indigenous bentonite clay deposits in Khyber Pakhtunkhwa for As decontamination and adsorption mechanism. Bentonite deposits in Khyber Pakhtunkhwa Province from Nowshera, Spin Kana, Spin Khak, and Peshawar were sampled. Along with other physicochemical properties, the detailed mineral composition of the clays was determined through X-ray diffraction analysis, total elemental composition through X-ray fluorescence analysis, and surface area through BET. The As adsorption capacity was determined through a batch sorption experiment by equilibrating uniform clay mass with different concentrations of As. Adsorption data were fitted to Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin equations for adsorption parameters. Results showed that Nowshera bentonite was fine in texture, while Peshawar bentonite was rich in quartz (coarse texture) and cation exchange capacity (CEC), and specific surface area was greater for Nowshera bentonite followed by Spin Kana, Spin Khak, and Peshawar clays. Smectite occurred as the dominant mineral in Nowshera bentonite, while mica, quartz, feldspar, and calcite were the major mineral impurities in all the bentonites. The Nowshera bentonite rich in smectite adsorbed the maximum As (1040 mg kg −1 ) from the solution with greater affinity. Freundlich equation had a better fit compared to other adsorption equations indicating chemisorption of As on heterogeneous surfaces. It can be inferred from the study that Nowshera bentonite has the greatest As adsorption capacity and adsorption affinity. Arsenic sorption on smectite clays was mainly through chemisorption; bentonites with greater mineral impurities had lower As adsorption potential. The clay quarry of Nowshera could be utilized for the effective purification of As-polluted drinking water. | Controlling Arsenic Contamination Through Bentonite Clays: a Batch Sorption Study | 10.1007/s42729-023-01191-w |
2023-06-01 | Low-power pulsed laser-MAG hybrid welding was carried out by different heat source arrangement methods (lead mode, distance between laser spot and welding wire tip ( D LA )). The coupling effect and welding characteristics of hybrid heat sources under different modes were studied by using high-speed image ( HSI ) and real-time electrical signals. HSI observation and electronic signals showed that the lead mode and D LA significantly affected the coupling state of the heat source and welding characteristics (weld morphology, process stability, and droplet transfer). The influence of lead mode on weld forming was more significant than that of D LA . In laser-lead mode, when D LA = 1 ~ 2 mm, the laser and arc generated a perfect coupling effect, resulting in a good weld formation, less spatter, and greater penetration. In arc-lead mode, the weld formation was poor and the undercut defect was common, while the penetration was greater than that in laser-lead mode. In terms of welding process stability, the arc-lead mode was better than the laser-lead mode. When D LA = 1 ~ 2 mm, stable droplet transfer could be realized under both modes. | Influence of heat source arrangement on coupling characteristics of low-power pulsed laser-MAG hybrid welding | 10.1007/s00170-023-11227-1 |
2023-06-01 | Background: Human umbilical cord mesenchymal stem cells (hUCMSCs) have emerged as promising therapy for immune and inflammatory diseases. However, how to maintain the activity and unique properties during cold storage and transportation is one of the key factors affecting the therapeutic efficiency of hUCMSCs. Schisandrin B (SchB) has many functions in cell protection as a natural medicine. In this study, we investigated the protective effects of SchB on the hypothermic preservation of hUCMSCs. Methods: hUCMSCs were isolated from Wharton’s jelly. Subsequently, hUCMSCs were exposed to cold storage (4 °C) and 24-h re-warming. After that, cells viability, surface markers, immunomodulatory effects, reactive oxygen species (ROS), mitochondrial integrity, apoptosis-related and antioxidant proteins expression level were evaluated. Results: SchB significantly alleviated the cells injury and maintained unique properties such as differentiation potential, level of surface markers and immunomodulatory effects of hUCMSCs. The protective effects of SchB on hUCMSCs after hypothermic storage seemed associated with its inhibition of apoptosis and the anti-oxidative stress effect mediated by nuclear factor erythroid 2–related factor 2 signaling. Conclusion: These results demonstrate SchB could be used as an agent for hypothermic preservation of hUCMSCs. | Schisandrin B Improves the Hypothermic Preservation of Celsior Solution in Human Umbilical Cord Mesenchymal Stem Cells | 10.1007/s13770-023-00531-2 |
2023-06-01 | In the present work, the MoN-MoS x composite coatings were prepared by reactive sputtering of Mo and MoS 2 targets. The influence of MoS 2 target power on the structure, morphology and mechanical properties of composite coatings was investigated, and the tribological properties of coatings were evaluated under PAO6 base oil lubrication. As the increase of MoS 2 target power was from 0 to 1000 W, the highest coating hardness and the optimized tribological performances were achieved at 400 W. Different from pure MoN coating, it was observed that MoN-MoS x composite coatings exhibited a time-dependent friction behavior, the friction coefficients and wear rates slowly decreased with the extension of sliding time. As the sliding test lasted for 4 h, the MoN-MoS x coating with the highest hardness gave a lower friction coefficient (~ 0.06) and significantly higher wear resistance (1.1 × 10 −9 mm 3 /N·m). Worn surface analysis indicated that a tribofilm containing MoS 2 , Mo oxides, and sulfates on steel ball could be associated with the excellent friction and wear properties of MoN-MoS x coating solid–liquid composite lubrication. As a result, it can be concluded that such MoN-MoS x coating offers a new candidate for tribological engineering toward future green and high-performance applications. | MoN-MoSx Coating Achieving Excellent Tribological Properties in Solid–Liquid Composite Lubrication through a Time-Dependent Tribofilm | 10.1007/s11665-022-07457-1 |
2023-06-01 | In the present work, the interaction of Sb and initial annealing before single-roll drive rolling on the microstructure, crystallographic texture, and magnetic behavior of 1.2 wt% Si steel was studied. Steel ingots with different antimony percentages were produced under the Ar atmosphere. After homogenization, they were subjected to symmetric hot-rolling. The produced sheets were then divided into two groups. The first group was cold-rolled to 1 mm thickness using a single-roll drive rolling machine, while the second group was subjected to initial annealing before asymmetric cold-rolling. Finally, all samples were annealed at 1000 °C for 3 min. Microstructural studies showed that with the addition of antimony, the mean grain size of samples was decreased. This effect was less significant in samples subjected to initial annealing. Moreover, the addition of antimony positively affected the desired texture. In specific, it yielded a gradual increase of θ-fiber in samples. The intensity of θ-fiber was higher in samples subjected to initial annealing compared with those without initial annealing. The comparison of the effect of average grain size and texture on magnetic behavior showed that grain size acted as the dominant parameter as the coercivity and remanence increased with decreasing grain size. However, in constant grain size, the texture played the main role in enhancing the magnetic behavior by increasing the θ-fiber intensity. The results showed that the combination of antimony and initial annealing before single-roll drive rolling resulted in the best magnetic performance in a low silicon steel sheet. Graphical Abstract | Effect of Sb and Initial Annealing on the Microstructure, Texture, and Magnetic Behavior of Low Silicon Steel Produced by Single-Roll Drive Rolling | 10.1007/s12540-022-01337-y |
2023-06-01 | One-phase-low-pH MICP (Microbially Induced Carbonate Precipitation) or EICP (Enzyme Induced Carbonate Precipitation) is a new biocementation method for soil improvement. This method uses the low pH of bacterial or urease solution to provide a delay for the MICP or EICP process so that the treatment solution can be evenly distributed in soil during grouting. However, how are the delay duration and the effect of biocementation affected by the initial pH (pH 0 ) of bacterial or urease solution has not been studied. In this paper, an experimental study using different pH 0 of urease (or bacterial) solution for EICP (or MICP) biocementation is presented. The study shows that the lower the pH 0 , the longer the delay period. However, the EICP or MICP process becomes ineffective when the pH 0 is equal to or lower than 4.5 or 4.0 for EICP and MICP, respectively. The pH 0 also has a significant effect on the strength of treated sand by affecting the morphology and crystallinity of precipitated calcium carbonate crystals. The pH 0 on the other hand, has little effect on the amount of calcium carbonate production and its distribution in soil as long as the delay duration is sufficient for the distribution of treatment solution in soil. | Effect of pH on soil improvement using one-phase-low-pH MICP or EICP biocementation method | 10.1007/s11440-022-01759-3 |
2023-06-01 | Abstract The possibility of estimating the defect sizes during the preparation of samples with artificial defects using eddy current testing is considered. The designs of orthogonal and absolute eddy current probes are compared, and it is recommended to use absolute eddy current probes for materials with a high electrical conductivity. An analysis of the obtained experimental results shows that the sensitivity and accuracy of the eddy current method can be significantly increased during static loading of samples (creation of tensile strains in the defect zone). This finding will allow us to prepare samples with defects the sizes of which are significantly smaller than those detected by standard control systems. | Application of Eddy Current Testing for the Preparation of Samples with Artificial Defects | 10.1134/S003602952306037X |
2023-06-01 | The Eastern Indian Ocean is a tectonically and geodynamically active region that has experienced deformations due to rifting, uplifting, and plume activity. The earlier Rayleigh wave studies in the East Indian Ocean were mainly focused on the structure of the Bay of Bengal, Ninety East Ridge, and Broken Ridge. The structure of other region of the East Indian Ocean is not much explored. In the present study, Rayleigh wave dispersion analysis is performed to observe the signatures of upper mantle deformation in terms of shear wave velocity of the East Indian Ocean using global search method. The fundamental mode Rayleigh wave group velocities are estimated between 15 and 100 s using the multiple filter technique. The group velocities of the raypaths that traverse the same region are clustered (E1–E8) to get an average dispersion curve. Using a genetic algorithm, each cluster's group velocities are inverted for shear velocity structure. The observed dispersion curve of E6, E7, and E8 indicates the lower group velocities between 35 and 100 s relative to E1, E2, E3, E4, and E5, with an average variation of about 0.07–0.18 km/s. The crustal thickness obtained in the study region is ~ 26 km and is due to the increased thickness of the lower crust (9.1–12.4 km) having Vs 3.95–4.04 km/s. The theoretical Vs have been calculated for serpentinite rock at uppermost lithospheric conditions and found to be similar to the Vs of the lower crust in the present study. Hence, it is assumed that unusual crustal thickness is due to the progressive development of the upper lithosphere formation (Ultramafic rock) into material (serpentinite rock) with crustal-like shear velocity or moderately lower than sub-Moho shears velocity. The undeformed lithosphere is evidenced by the high-velocity (Vs 4.62–4.77 km/s) layer beneath the Moho, whose thickness ranges from 41.3 to 51.6 km. The high-velocity lithosphere is followed by a low-velocity zone that extends up to 160 km; however, the variation in Vs (4.57–4.31 km/s) indicates that the low-velocity zone is deformed. | Shear wave velocity structure beneath the eastern Indian Ocean from Rayleigh wave dispersion measurements | 10.1007/s11600-023-01045-0 |
2023-06-01 | The seismic performance of precast reinforced concrete structures has long been a source of concern that impedes their use in seismic regions and high-rise buildings. To further optimize the reinforcement configuration and enhance the seismic performance of the superimposed slab shear wall structures, this research proposed a superimposed slab shear wall with innovative construction details. Five innovative superimposed slab shear walls and one cast-in-place concrete shear wall were designed and tested under low cycle lateral load. The effect of axial compression was considered during tests and analyses as well. In this paper, the seismic performance, including failure mode, hysteretic behavior, load-bearing capacity, lateral stiffness degradation, energy dissipation, and seismic ductility was investigated and analyzed. The experimental results showed that five innovative superimposed slab shear walls and one cast-in-place concrete shear wall exhibited a similar failure mode of flexural-shear failure, and a large area of concrete was damaged and crushed at the shear wall corner. However, the area of crushing concrete in the cast-in-place concrete shear wall was relatively small. And the area of crushing concrete in the superimposed slab shear walls increased with the axial compression ratio. For the superimposed slab shear walls, the development of concrete cracks decreased gradually with the enlargement in the axial compression ratio, while the length of the cracks increased in this respect. The results indicated that innovative superimposed slab shear walls had a higher strength capacity and lower lateral-resistant stiffness than the cast-in-place concrete shear wall. With the enlargement in the axial compression ratio, the peak strength capacity of the superimposed slab shear wall increased obviously, while it degraded rapidly after the peak load. It is suggested that the contribution of axial compression to the shear resist capacity of the inclined section should not be considered in practical design. Meanwhile, the ductility coefficients of the six specimens were larger than 2.2, which was in accordance with the seismic requirements. This investigation could provide effective experimental data for future structural seismic performance evaluations and applications of precast superimposed slab shear wall structures. | Experimental Study on the Seismic Mechanism of Full-scale Specimens of Superimposed Slab Shear Walls with Innovative Construction Details | 10.1007/s12205-023-2338-4 |
2023-06-01 | The rapid emergence of antimicrobial resistance represents a major public health threaten, which necessitates the discovery of novel antibacterial agents. In this study, four gemcitabine derivatives were synthesized by introduction of aromatic substituents at the amine group. Then, the derivates were evaluated for in vitro antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) ATCC 33591 and methicillin-sensitive S. aureus (MSSA) ATCC 25923. All derivatives exhibited moderate or good antibacterial activity, among which GEM-3 displayed the most potent antibacterial activity with low minimum inhibitory concentration (MIC) values of 0.5 μg/mL against both MRSA ATCC 33591 and MSSA ATCC 25923. Furthermore, all derivatives showed low cytotoxicity toward human normal cells and tumor cells. Moreover, all derivatives exhibited low hemolytic rates. Besides, the molecular docking study implied that these derivatives may work through targeting deoxyadenosine kinase. Taken together, with potent antibacterial activities and low toxicity profiles, gemcitabine derivatives may be promising lead compounds for antibacterial agents. | Discovery of Gemcitabine Derivatives as Potent Inhibitors Against Drug-Resistant Bacteria with Decreased Toxicity Profiles | 10.1007/s11094-023-02897-y |
2023-06-01 | Background N6-methyladenosine (m6A) modification is involved in tumorigenesis and progression as well as closely correlated with stem cell differentiation and pluripotency. Moreover, tumor progression includes the acquisition of stemness characteristics and accumulating loss of differentiation phenotype. Therefore, we integrated m6A modification and stemness indicator mRNAsi to classify patients and predict prognosis for LGG. Methods We performed consensus clustering, weighted gene co-expression network analysis, and least absolute shrinkage and selection operator Cox regression analysis to identify an m6A regulation- and mRNAsi-related prognostic index (MRMRPI). Based on this prognostic index, we also explored the differences in immune microenvironments between high- and low-risk populations. Next, immunotherapy responses were also predicted. Moreover, single-cell RNA sequencing data was further used to verify the expression of these genes in MRMRPI. At last, the tumor-promoting and tumor-associated macrophage polarization roles of TIMP1 in LGG were validated by in vitro experiments. Results Ten genes (DGCR10, CYP2E1, CSMD3, HOXB3, CABP4, AVIL, PTCRA, TIMP1, CLEC18A, and SAMD9) were identified to construct the MRMRPI, which was able to successfully classify patients into high- and low-risk group. Significant differences in prognosis, immune microenvironment, and immunotherapy responses were found between distinct groups. A nomogram integrating the MRMRPI and other prognostic factors were also developed to accurately predict prognosis. Moreover, in vitro experiments illustrated that inhibition of TIMP1 could inhibit the proliferation, migration, and invasion of LGG cells and also inhibit the polarization of tumor-associated macrophages. Conclusion These findings provide novel insights into understanding the interactions of m6A methylation regulation and tumor stemness on LGG development and contribute to guiding more precise immunotherapy strategies. | An N6-methyladenosine regulation- and mRNAsi-related prognostic index reveals the distinct immune microenvironment and immunotherapy responses in lower-grade glioma | 10.1186/s12859-023-05328-7 |
2023-06-01 | Abstract —The dependences of the resistance and inductive reactance of the laminated busbar stacks of ore-smelting furnaces on the geometry, the method of restacking conductors, and the distance between them are studied by numerical simulation of the electromagnetic field of conductor systems using the ANSYS software package. The resistance of the busbars is shown to be comparable with their inductive reactance, and this finding should be taken into account to design them. New versions of busbar stacks have been developed for the phase resistances to be symmetrical. | Impedance of the Busbar Stacks of Ore-Smelting Furnaces as a Function of Their Design | 10.1134/S0036029523060083 |
2023-06-01 | Background and objectives Research suggests that diabetic peripheral neuropathy (DPN) is related to high serum uric acid (SUA) level, although its correlation with low SUA level has not been reported. Here, diabetic patients with hyperuricemia were excluded, and the correlation between low SUA level and DPN was explored. Subjects and methods This prospective observational clinical study enrolled 525 type 2 diabetes mellitus (T2DM) patients without hyperuricemia, who were divided into the diabetes with symptomatic neuropathy (150 cases), diabetes with asymptomatic neuropathy (125 cases) and diabetes with no neuropathy (250 cases) groups. Results The SUA slightly decreased in subjects with asymptomatic DPN compared with those with no neuropathy and greatly decreased in subjects with symptomatic DPN compared with those without ( P < 0.001). The association of the SUA with diabetic neuropathy was independent of the hyperglycemic state and other potential confounders (odds ratio 0.985 [0.981–0.988], P < 0.001). The SUA was closely correlated with the means of motor/sensory nerve amplitude and CV (all P < 0.001). The optimal cut-off point for SUA to distinguish patients with diabetic neuropathy from those without was 324 umol/L, with a sensitivity of 76.0% and a specificity of 79.2% (AUC = 0.806). Conclusions The low SUA level is closely associated with DPN. Future studies are warranted to clarify the relationship. | Serum uric acid and diabetic peripheral neuropathy: a double-edged sword | 10.1007/s13760-022-01978-1 |
2023-06-01 | Over the past 20 years, the literature on corporate responses to climate change has offered a vast array of theoretical and practical insights into organizational efforts to reduce business-related carbon emissions. However, it remains unclear whether these efforts will result in significant reductions of carbon emissions. Presently, it becomes crucial to understand, if, why, and how companies can effectively respond to the current challenges of deep decarbonization, defined as the process of emission reduction down to, or close to, zero to limit global warming. By means of a systematic literature review with 370 identified papers, we are able to categorize the main findings of the literature according to the four most common areas of investigation, including drivers, actions, barriers, and facilitators. Additionally, we conduct a comparative analysis of the literature along these four areas of investigation according to two categories: conventional responses and deep decarbonization responses. The results show that the literature on conventional responses to climate change (n = 321) extensively covers all four areas of investigation; however, it only touches on the descriptive (i.e., ‘what’) aspects of decarbonization. The recent and emerging literature on deep decarbonization responses (n = 49) provides novel insights on the prescriptive (i.e., ‘why’ and ‘how’) aspects of deep decarbonization. However, this literature is restricted to mostly regional and industrial foci, and it does not connect drivers, barriers, and facilitators in a systematic way. Thus, we highlight key implications for future research and practice in order to effectively address corporate deep decarbonization. | Beyond conventional corporate responses to climate change towards deep decarbonization: a systematic literature review | 10.1007/s11301-023-00318-8 |
2023-06-01 | By coating the inside of an overmoded, smooth wall metallic waveguide with a thin dielectric layer, one can obtain similar boundary conditions to corrugated waveguides and achieve extremely low transmission loss propagating the HE 11 mode. A theoretical model provides an analytic method for computing attenuation. The propagation mode of a prototype dielectric lined waveguide is characterized using low power transmission measurements to analyze the beam radiated from the waveguide aperture. Results indicate HE 11 mode purity of approximately 98%. Furthermore, we quantified attenuation with low power Fabry-Pérot measurements, verifying low loss performance of the experimental prototype. These results demonstrate that dielectric lined waveguides could have applications in many fields demanding low attenuation millimeter and terahertz transmission, such as radar, high-frequency communication systems, THz dynamic nuclear polarization, and electron cyclotron heating in magnetically confined fusion experiments. | Measurements of Dielectric Lined Waveguides for Low Loss Millimeter Wave and Terahertz Transmission | 10.1007/s10762-023-00912-7 |
2023-06-01 | Purpose Low expression of HER2 (HER2-low expression) in breast cancer (BC) has unique biological characteristics. However, whether HER2-low expression has an impact on neoadjuvant chemotherapy (NACT) in HER2-negative breast cancer remains unclear. Methods This study reviewed the clinicopathological data of patients with BC treated with NACT at a single hospital from January 2018 to July 2022. Baseline patient characteristics, efficacy of NACT, and survival data were compared between the HER2-0 and HER2-low groups. The impact of NACT on HER2 status also was investigated. Subgroup analyses based on hormone receptor (HR) status were performed to explore the impact of HR signaling on HER2 status during chemotherapy. Results The progesterone receptor-positive rate in the HER2-low group was significantly higher than that in HER2-0 group. The local treatment response of the HER2-low group was worse, but the disease-free survival rate of the HER2-low group was significantly better than that of the HER2-0 group. The proportion of patients with increased HER2 immunohistochemistry score after NACT was significantly higher in the HER2-0 group. Subgroup analysis showed that the efficacy of chemotherapy in HR + patients was significantly worse than in HR− patients, and HR + patients had a higher proportion of increased HER2 immunohistochemistry score after chemotherapy. Mechanistic studies suggested that MLH1 expression loss during chemotherapy might link HR signaling and regulation of HER2 expression. Conclusions We found that HER2-low expressing BC exhibits differential sensitivity to chemotherapy compared to HER2-0 expressing BC. The regulation of HER2 expression by HR signaling may mediate aspects of chemoresistance. | The impact of HER2-low status on response to neoadjuvant chemotherapy in clinically HER2-negative breast cancer | 10.1007/s12094-022-03062-9 |
2023-06-01 | This study suggests using user-initiated detecting and data gathering from power-limited and even passive wireless devices, such as passive RFID tags, wireless sensor networks (WSNs), and Internet of Things (IoT) devices, that either power limitation or poor cellular coverage prevents them from communicating directly with wireless networks. While previous studies focused on sensors that continuously transmit their data, the focus of this study is on passive devices. The key idea is that instead of receiving the data transmitted by the sensor nodes, an external device (a reader), such as an unnamed aerial vehicle (UAV), or a smartphone is used to detect IoT devices and read the data stored in the sensor nodes, and then deliver it to the cloud, in which it is stored and processed. While previous studies on UAV-aided data collection from WSNs focused on UAV path planning, the focus of this study is on the rate at which the passive sensor nodes should be polled. That is, to find the minimal monitoring rate that still guarantees accurate and reliable data collection. The proposed scheme enables us to deploy wireless sensor networks over a large geographic area (e.g., for agricultural applications), in which the cellular coverage is very poor if any. Furthermore, the usage of initiated data collection can enable the deployment of passive WSNs. Thus, can significantly reduce both the operational cost, as well as the deployment cost, of the WSN. The performance of the proposed scheme was validated by simulation. The simulation results demonstrate a significant reduction in the power consumption of the sensors, in comparison with the power consumed by sensors in conventional WSNs. | Monitoring Passive Wireless Devices | 10.1007/s10776-023-00594-x |
2023-06-01 | Climate change (CC) will most likely alter the future low flows and adapting to its impact is the key to successful management of water resources. This study investigates CC impact on the full spectrum of low flows by taking the case of Budhigandaki River Basin under RCP 4.5 and RCP 8.5, considering baseline flows (1983–2012) and ensembled future flows (2021–2099). Gumbel distribution is found to be the best fit for 1-day, 7-day, 30-day, and monthly low flow series and the same is used to compare the future 2, 5, 10, 20, 25 and 50-year return period low flows against the corresponding baseline flows for three time windows: Near (2021–2050), Mid (2046–2075) and Far Future (2070–2099). Our results analyzing 72 scenarios show that future low flows are expected to increase compared to the corresponding baseline flows for all return periods, emission scenarios and time windows. It can be attributed to higher anticipated future rainfall in the basin. The respective changes are higher under RCP 8.5 than under RCP 4.5. The change in the projected low flows compared to the baseline for different durations increases with the return period under both RCPs in all the time windows. Contrary to the popular belief, CC is expected to have positive implications on low flows in this region. | Impact of climate change on the full spectrum of future low flows of Budhigandaki River Basin in Nepal using Gumbel distribution | 10.1007/s42108-022-00214-z |
2023-06-01 | Abstract The surface treatment of ultra-high-molecular-weight polyethylene (UHMWPE) in helium plasma at a pressure of 0.133 mbar has been studied by IR spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscopy. It has been shown that the helium plasma treatment leads to the formation of double bonds in the UHMWPE surface layer and the associated formation of intermolecular crosslinks. The crosslinking of the surface layer is accompanied by a decrease in the nanowear of the UHMWPE surface by more than three orders of magnitude, which is confirmed by measurements using an atomic force microscope in the contact mode. | Structure Modification and Enhancement of Wear Resistance of Ultra-High-Molecular-Weight Polyethylene by Low-Pressure Helium Plasma Treatment | 10.1134/S0018143923010137 |
2023-06-01 | With the recent realization of exascale performance by Oak Ridge National Laboratory’s Frontier supercomputer, reducing communication in kernels like QR factorization has become even more imperative. Low-synchronization Gram-Schmidt methods, first introduced in Świrydowicz et al. ( Numer. Lin. Alg. Appl. 28(2):e2343, 2020 ), have been shown to improve the scalability of the Arnoldi method in high-performance distributed computing. Block versions of low-synchronization Gram-Schmidt show further potential for speeding up algorithms, as column-batching allows for maximizing cache usage with matrix-matrix operations. In this work, low-synchronization block Gram-Schmidt variants from Carson et al. ( Linear Algebra Appl. 638:150–195, 2022 ) are transformed into block Arnoldi variants for use in block full orthogonalization methods (BFOM) and block generalized minimal residual methods (BGMRES). An adaptive restarting heuristic is developed to handle instabilities that arise with the increasing condition number of the Krylov basis. The performance, accuracy, and stability of these methods are assessed via a flexible benchmarking tool written in MATLAB. The modularity of the tool additionally permits generalized block inner products, like the global inner product. | Adaptively restarted block Krylov subspace methods with low-synchronization skeletons | 10.1007/s11075-022-01437-1 |
2023-06-01 | Inertial and nonlinear friction parameters precise identification of Stewart platform (SP) is a pending problem owing to the strong coupling and small workspace. This paper proposes a novel identification model based on symmetric excitation trajectory (SET), which is verified on low impact docking mechanism (LIDM, a typical SP). Firstly, the SET is defined, and its decoupling and filtering characteristics of the SP are analyzed. The dynamic equation of the LIDM is derived from Boltzmann–Hamel–d’alembert formula, and a typical dynamic parameter identification model (TM) is obtained. Then, a symmetric dynamic parameter identification model (SM) with the decoupling characteristic is derived from the SET. Moreover, the SM is improved according to the nonlinear friction phenomenon, and a nonlinear dynamic parameter identification model (SM_Non) including acceleration term is established. Besides, the speed-span index is given to ensure sufficient excitation of friction at different velocities during the identification process. Finally, experiments on the LIDM demonstrate the validity and accuracy of the proposed methods. The results of joint current prediction experiments show that the root mean square error of the SM_Non is 92.789% lower than that of the TM. | Dynamic modeling and identification of low impact docking mechanism based on symmetric excitation trajectory | 10.1007/s11071-023-08341-w |
2023-06-01 | Low phosphorus (P) availability is a major problem for cotton production. However, little is known about cotton agronomic and physiological traits associated with low P tolerance. Therefore, the agronomic and physiological performance of three cotton genotypes with strong tolerance to low P (STGs) and three cotton genotypes with weak tolerance (WTGs) was characterized under low and normal P conditions in hydroponic and pot culture. The results showed that low P significantly reduced dry matter production, photosynthesis, and carbon metabolism in both STGs and WTGs; however, the reduction was more in WTGs. In contrast, low P improved root morphology, carbohydrate accumulation, and P metabolism, especially in STGs genotype Jimian169, whereas the opposite responses were observed for WTGs mainly DES926. The multivariate analysis suggested that root morphological traits, carbohydrate contents, and enzymes related to P metabolism were strong positively correlated and contributed more to the genotypic variation, suggesting the importance of root over shoot in low P tolerance. Moreover, plants grown under low P produced low yields than normal P, whereas WTGs yields were lower than the STGs yield. Overall, it was suggested that the low P tolerance of cotton genotypes is closely related to root morphology and physiology. In the future, the identified contrasting low P tolerant cotton genotypes Jimian169 and DES926 will be used to understand the molecular mechanisms of low P tolerance in cotton. | Low Phosphorus Tolerance in Cotton Genotypes is Regulated by Root Morphology and Physiology | 10.1007/s00344-022-10829-5 |
2023-06-01 | The effects of blood benzene, toluene, ethylbenzene, and xylenes (BTEX) on lung function among general adults remain unknown. We enrolled 5519 adults with measured blood BTEX concentrations and lung function from the US National Health and Nutrition Examination Survey 2007–2012. Weighted linear models were fitted to assess the associations of BTEX with lung function and inflammation parameters (white blood cell five-part differential count and C-reactive protein). The mediating effect of inflammation between BTEX and lung function was also examined. Blood BTEX concentrations decreased yearly from 1999 and were extremely low from 2007 to 2012. Benzene and toluene exerted the greatest influence on lung function in terms of forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), calculated FEV1:FVC ratio, peak expiratory flow rate (PEFR), and forced mid expiratory flow (FEF 25–75% ). Both ethylbenzene and all xylene isomers had no effects on FVC but reduced FEV1, FEV1:FVC ratio, PEFR, and FEF 25–75% . Weighted quantile analyses demonstrated that BTEX mixture was associated with decreases in FVC, FEV1, FEV1:FVC ratio, PEFR, and FEF 25–75% , with benzene weighted most heavily for all lung function parameters. BTEX also increased the levels of inflammation indicated by white blood cell five-part differential count and C-reactive protein, and increased levels of inflammation also reduced lung function. From multiple mediation analysis, inflammation mediated the effects of benzene on FEV1 and PEFR, the effects of toluene on FEV1, and the effects of ethylbenzene on FEV1 and PEFR. Low-dose exposure to BTEX was associated with reduced pulmonary function both in large and small airways. Inflammation could be involved in this pathogenesis. | Low-dose blood BTEX are associated with pulmonary function through changes in inflammatory markers among US adults: NHANES 2007–2012 | 10.1007/s11356-023-27181-0 |
2023-06-01 | International expeditions extensively excavated Lower Nubia (between the First and Second Nile Cataracts) before it was submerged under the waters of Lake Nasser and Lake Nubia. The expeditions concentrated on monumental architecture and cemeteries, including sites at Qustul and Serra East, where the New Kingdom, and Napatan, Meroitic, Nobadian, and Makurian-period elites and common people were buried, ca. 1400 BC–AD 1400. Although the finds abound in adornments, including bead imports from Egypt and South India/Sri Lanka, only a few traces of local glass bead-making have been recorded in Nubia so far. Based on results of laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) analysis of 76 glass beads, pendants, and chunks from Qustul and Serra East contexts, dated between the New Kingdom and the Makuria Kingdom periods, this paper discusses the composition and provenance of two types of plant-ash soda-lime (v-Na-Ca) glass, two types of mineral soda-lime glass (m-Na-Ca), and two types of mineral-soda-high alumina (m-Na-Al) glass. It also presents the remains of a probable local glass bead-making workshop dated to the period of intensive long-distance bead trade in Northeast Africa, AD 400–600. La Basse Nubie (région située entre la Première et la Deuxième Cataracte du Nil) a fait l’objet de fouilles extensives par des missions internationales, avant d’être submergée par les eaux du lac Nasser et du lac de Nubie. Les expéditions ont concentré leurs efforts sur l’architecture monumentale et les nécropoles, incluant des sites comme Qustul et Serra Est, où étaient enterrés les élites et les gens ordinaires pendant près d’un millénaire. En effet, les sépultures de ces cimetières datent du Nouvel Empire, ainsi que des périodes Napatéenne, Méroïtique, Nobadienne et Makurite (14 e s. av. J.-C. – 14 e s. ap. J.-C.). Bien que les trouvailles archéologiques d’ornements personnels soient nombreuses, y compris des perles importées d’Egypte et du Sud de l’Inde/Sri Lanka, les traces d’une manufacture locale du verre en Nubie restent rares. En se basant sur les résultats d’analyse obtenus par spectrométrie de masse à plasma inductif avec prélèvement par ablation laser (LA-ICP-MS) de 76 perles, pendentifs et morceaux de verre de Qustul et Serra Est, cet article discute la composition et la provenance des types de verre, datés entre l’époque du Nouvel Empire et la période du royaume de Makuria. Au total deux types de verre sodo-calcique à base de cendres végétales (v-Na-Ca), deux types de verre sodo-calcique à la soude minérale (m-Na-Ca) et deux types de verre à la soude minérale et à fortes teneurs en alumine (m-Na-Al) ont été identifiés. L’article présente également les restes d’un probable atelier de perles en verre actif durant une période pendant laquelle ce type d’ornements étaient l’objet d’un intense commerce à longue distance en Afrique du Nord-Est (4 e – 6 e s. ap. J.-C.). | Teardrops at the Lake: Chemistry of New Kingdom to Makuria Glass Beads and Pendants Between the First and Second Nile Cataracts | 10.1007/s10437-021-09467-1 |
2023-06-01 | A study was conducted to design, develop and evaluate a low-cost willow wicker peeling machine for farmers and wicker craft industry of Jammu and Kashmir. The relevant physical characteristics of willow wicker were measured in terms of length, diameter and peel thickness to finalize the design values of individual working components of willow wicker machine. The machine comprised of hopper, peeling rollers, electric motor and discharging unit with overall dimension of 736 × 406 × 609 mm. The evaluation was carried out at three moisture content (13, 18 and 23% w.b), roller speeds (350, 700 and 1050 rpm) and wicker varieties ( Salix triandra, Salix purpurea and Salix viminalis ). The optimization of the data through design expert 10.0.1 revealed that operating the machine at 700 rpm with S. purpurea variety containing 13% (w.b) moisture content resulted in throughput capacity of 15 twigs/min, 83.85% peeling efficiency, 0.74% damage percentage, 0.064 man-min/twig labour requirement and 1.4 kJ/twig specific mechanical energy consumption. The cost economics showed that operating the machine requires 64.3 Rs h −1 with benefit–cost ratio of 2.35:1, breakeven point of 109,800 twigs and payback period of 640.44 hours. The comparative analysis showed the cost difference of Rs. 45 per hour between manual and mechanical peeling of willow wicker twigs. The weight of the machine was recorded as 53 kilograms. The study can be useful for wicker craft (keani keam) industry with huge employment and entrepreneurship generation potential. | A Low-Cost Portable Willow Wicker Peeling Machine: An Innovative Mechanical Intervention in the Wickercraft Industry of Kashmir | 10.1007/s40030-023-00726-9 |
2023-06-01 | About one tenth of humans are impacted by water shortages around the globe. Water resilience is worsening under climate change because intensifying weather extremes induce more severe and increasingly frequent droughts and floods. In particular, China, as the world’s most populous nation, has battled with persisting water shortages and devastating floods for decades. As a consequence, Chinese scholars have designed the sponge city concept in the early 2010s to relieve cities from the growing pressure of water shortages and floods. This is done by integrating a more natural, green infrastructure into existing urban drainage pipeline systems for absorbing, storing, and purifying rainwater in a sponge-like manner during rainfall events. Here we review the principles, design guidelines, construction items and assessment requirements of sponge cities and other similar strategies for urban stormwater management. We present four case studies of sponge cities in China in both newly constructed and renovated urban districts. Overall, China's sponge cities appear promising for green urbanization, to relieve cities from water scarcity, devastating floods and urban heat island effects, while restoring the ecological functions and aesthetics of urban natural environments. | China’s sponge cities alleviate urban flooding and water shortage: a review | 10.1007/s10311-022-01559-x |
2023-06-01 | Abstract —Nerve growth factor (NGF) contributes to the proliferation, differentiation, and maintenance of the viability and functioning of peripheral and central neurons. At the Zakusov Research Institute of Pharmacology, a dimeric dipeptide mimetic of the NGF loop 4 bis-(monosuccinyl-L-glutamyl-L-lysine) hexamethylenediamide (GK-2) was created. GK-2 activates PI3K/AKT and PLC-γ1 signaling cascades, without affecting MAPK/ERK, and appears to have procognitive properties. In the present study, we investigated the mnemotropic effects of GK-2 with a single intraperitoneal dose of 0.1, 0.5, and 5.0 mg/kg in the novel object recognition test in rats. GK-2 at a dose of 0.5 mg/kg significantly improved the long-term memory of animals. In experiments with acute hippocampal slices of rats, we evaluated the effects of GK-2 on synaptic transmission and its plastic properties in the Schaffer collaterals–CA1 pyramidal cell synaptic system. | The Effects of the Low Molecular Weight Nerve Growth Factor Mimetic GK-2 on Cognitive Function and Synaptic Transmission in Hippocampal Slices | 10.1134/S1819712423020186 |
2023-06-01 | The geophysical challenges low-velocity layers pose during the acquisition of reflection seismic data and even in the construction of structures are enormous. This is due to the heterogeneity, low compaction and high porosity of the weathered zones or layers which make these zones exhibit low-velocity characteristics that cause delay or reduction in travel time experienced between the source of seismic energy generation and signal receiver during the propagation of seismic energy or waves. These very poorly compacted zones do not only affect seismic reflection data acquisition negatively, but also affect structures as well, leading to collapse in most cases, hence this research. The results obtained from the downhole refraction survey carried out in the study area indicate a velocity model that has two layers with the thicknesses of weathering layers ranging from 8.6 to 15.1 m, having an average value of 10.675 m, while weathered zone velocities vary from 869 to 997 m/s with an average velocity of 934.25 m/s. In a similar order, the velocities observed within the consolidated layer range between 1657 and 1722 m/s, having a regional average velocity of 1691.5 m/s. 3D models of weathered layer velocity and thickness as well as a 3D contour of elevation were generated; thickness and weathered velocity were also generated. | Investigation of geophysical effects of low-velocity layers in reflection seismic data acquisition and civil engineering | 10.1007/s13762-022-04436-w |
2023-06-01 | Abstract This study numerically examines the influences of transverse annulation around a cone surface on the characteristics of a flow over an orthocone. This work is inspired by Spyroceras , a fossilized genus of nautiloid cephalopods from the Paleozoic era, whose method of locomotion is understudied. As a baseline case, a flow over a smooth orthoconic model with a blunt cone end is investigated numerically at Reynolds numbers from 500 to 1500. As Reynolds increases, two different shedding mechanisms—hairpin-vortex wake and spiral-vortex wake—are captured. We notice that an introduction of annulation over the cone surface changes the critical Reynolds number for the transition of the shedding mechanism. The dominant shedding frequency increases with the Reynolds number for the smooth and annulated cone flows. Moreover, the annulation reduces the dominant frequency for the same Reynolds number and increases the time-averaged drag coefficient. Modal decompositions—Proper Orthogonal Decomposition (POD) and Spectral Proper Orthogonal Decomposition (SPOD)—are used to capture the coherent structures and their oscillating frequencies. We have captured modes corresponding to the hairpin-vortex wake and spiral-vortex wake shedding mechanisms. Comparing the leading POD modes for the smooth and the annulated cone flows, we find that the annulation can reduce the twisting effects of the coherent structures in the wake. Additionally, we find that the SPOD analysis can identify modes presenting both hairpin-vortex wake and spiral-vortex wake in one flow condition as leading modes, while the POD leading modes only reveal one shedding mechanism in each flow. Graphical abstract | Effects of annulation on low Reynolds number flows over an orthocone | 10.1007/s00162-023-00649-y |
2023-06-01 | The Andean region of Ecuador is being impacted by climate change, and improved best management practices for agriculture are needed to increase yields and food security. We conducted a study comparing different nitrogen (N) rates to determine the optimum N application rate for potato ( Solanum tuberosum L.) systems in this region. We examined five application rates of N: 0, 100, 200, 300, and 400 kg N ha − 1 . The results suggest that an N application rate of 300 kg N ha − 1 increased productivity and net income by 87% and 146%, respectively, compared to no application of N. We transferred these improved practices to farmers, and all farms increased their yields and net economic returns. The average yields and net economic returns for these farmers increased by 50% and 64%, respectively. Additional N use efficiency (NUE) studies are needed to continue increasing yields and economic returns for farmers in the Andean region. La región andina de Ecuador está siendo impactada por el cambio climático, y se necesitan mejores prácticas de manejo para la agricultura para aumentar los rendimientos y la seguridad alimentaria. Realizamos un estudio que comparó diferentes tasas de nitrógeno (N) para determinar la tasa óptima de aplicación de N para los sistemas de papa ( Solanum tuberosum L.) en esta región. Se examinaron cinco dosis de aplicación de N: 0, 100, 200, 300 y 400 kg N ha − 1 . Los resultados sugieren que una tasa de aplicación de N de 300 kg N ha − 1 aumentó la productividad y el ingreso neto en un 87% y 146%, respectivamente, en comparación con ninguna aplicación de N. Transferimos estas prácticas mejoradas a los agricultores, y todas las siembras aumentaron sus rendimientos y ganancias económicas netas. Los rendimientos medios y los rendimientos económicos netos para estos agricultores aumentaron en un 50% y 64%, respectivamente. Se necesitan estudios adicionales de eficiencia en el uso de N (NUE) para continuar aumentando los rendimientos y ganancias económicas para los agricultores de la región andina. | Nitrogen Management Can Increase Potato Yields and Food Security for Climate Change Adaptation in the Andean Region | 10.1007/s12230-023-09912-8 |
2023-05-31 | This study investigates the microstructural and mechanical properties of dissimilar alloy 718/720Li joints, contemplated for use in hot-end applications of aircraft engine components with service temperatures of up to 730°C. Microstructural characterization, microhardness, and room-temperature tensile tests were performed, followed by high-temperature tensile tests (650°C) on both as-welded and post-direct aging heat-treated conditions to analyze the performance of weld joints at high temperature. Results indicate that the friction welded joint interface in its as-welded condition exhibits lower hardness (240 HV at the heat affected zone) than the alloy 718 base material due to the dissolution of strengthening precipitates. However, post-weld direct aging (DA) with an alloy 718 aging cycle has improved the microhardness to be comparable to the parent materials. The peak hardness value of 478 HV achieved at the interface region is 26% higher than the as-welded condition. The dissimilar 718/720Li FRW joints in direct aging condition show room and high-temperature tensile strengths of 1374 and 1172 MPa, respectively. Similarly, during low-cycle fatigue testing, 718/720Li FRW joints in direct aging condition withstand up to 3648 cycles, comparable to the low-cycle fatigue life of the alloy 718 parent material, with failures away from the FRW weld interface and into the alloy 718 base material. The cyclic softening and hysteresis trend obtained during low-cycle fatigue tests of dissimilar 718/720Li friction welded joints are comparable with alloy 718 parent material. The dissimilar 718/720Li friction welded joints have a peak stress of 1097 MPa, which falls between low-strength alloy 718 and high-strength alloy 720Li. These findings confirm that friction welding of dissimilar nickel-based superalloys, such as alloy 718 with alloy 720Li, is promising for adaptation in aero engine applications. | Tensile and Low-Cycle Fatigue Behavior of Dissimilar Friction Welds of Alloy 718/Alloy 720Li | 10.1007/s11665-023-08348-9 |
2023-05-30 | In the present study, a systematic comparison of additively manufactured CoCrNi medium entropy alloy having face-centered-cubic (FCC) structure with standard FCC materials 316L austenitic stainless steel was carried out. The effect of energy density (71 J/mm 2 ) on microstructural heterogeneity and crystallographic orientation of planes parallel to the build direction ( X – Z ) and perpendicular to the build direction ( X – Y ) was recorded. Scanning electron microscopy, x-ray diffraction and electron backscattered diffraction techniques were used to reveal the surface and structural features. The effect of repetitive heating associated with layer-by-layer deposition of the X – Z axis was reflected as the favorable formation of the (1 1 1) plane at the expense of the (2 2 0) plane. The low angle grain boundaries at the X – Z axis have been decreased by ~ 27% compared to the X – Y axis for CoCrNi, while a ~ 17% reduction was recorded for 316L austenitic stainless steel. Furthermore, the decreasing trends in nanomechanical properties and wear resistance were observed, with a low number of low angle grain boundaries at the X – Z axis, by employing a nanoindenter. Significant microcracks in CoCrNi medium entropy alloy manifest the brittle fracture mode, whereas 316L alloy denotes the mixed type of failure mode. | Role of Microstructural Heterogeneity on Nanoscale Mechanical Properties and Wear Responses of Additively Manufactured CoCrNi Medium Entropy Alloy and 316L Stainless Steel | 10.1007/s11665-023-08339-w |
2023-05-29 | Optical fiber sensors have great potential for application in civil construction, especially in the field of structural health monitoring. However, one of the barriers to the diffusion of these sensors is allied to the fact that their implementation is quite expensive, mainly due to the high price of commercial optical interrogators. Therefore, the present work seeks to develop a low-cost optical interrogation system. For this, the present study proposes the development of this system based on the use of tunable filters and edge filters in the monitoring of low and high frequencies, and consequent digital processing of the collected signals through the find_picks algorithm and the Fourier transform. As a result, it was possible to observe the adequate functioning of the tunable filters, with the validation of the system using a FBG, and a previous simulation for the edge filter system with frequencies superior to 100 kHz. | Low-cost optical interrogator system for structural health monitoring | 10.1007/s41024-023-00313-2 |
2023-05-28 | Background This work presents the design and experimental data results of a functional rotating machine prototype supported by active magnetic bearings (AMBs), whose digital data acquisition and control system were entirely designed using a digital signal processing (DSP) microcontroller and other low-cost electronic components. Situating the case From studies on rotordynamics, AMBs, and control engineering, a computer code devoted to the design of AMBs was implemented. Methodology Subsequently, the characterization of the electronic components with the potential of application to the development and integration of the submodules of the control electronic system was carried out. Then, the three-dimensional mechanical design was performed to get the manufacturing plans and to allow for the rotordynamic analysis. Then, the design of the analog power control signal processing submodule was performed, as required to develop the digital-to-analog converter–serial peripheral interface (DAC-SPI) submodule (hardware and firmware) due to the limitation of the number of DAC outputs available on the microcontroller unit (MCU) with DSP features. About the case Experimental tests were performed with the rotor system based on the proportional–integral–derivative (PID) control parameters calculated in the numerical/computational model implemented in the MATLAB ® /Simulink environment. The obtained results demonstrated that the AMB was able to support the shaft operating at two different rotation speeds, namely 1500 and 1800 RPM. Under these conditions, the maximum vibration amplitude of the shaft reached 450 µm and 300 µm, respectively. Additionally, it was demonstrated that the design and construction of a functional rotating machine supported by AMBs using low-cost electronic hardware are feasible and constitute the main contribution of the present paper. The detailed discussion on the design of the associated hardware and firmware can be also considered as an important contribution of the present contribution. | Design and Implementation of a Low-Cost Active Magnetic Bearing | 10.1007/s42417-023-01018-z |
2023-05-27 | The Himalayan region witnesses several natural hazards like earthquakes and landslides due to the continental collisions between the Indian and Eurasian plates. This has given rise to extreme topographic variations throughout the Himalayan belt. The Kumaun–Garhwal region is a classic example of such geological consequences and is prone to several earthquakes. High-quality three-component teleseismic waveform data recorded at seven seismological stations operated by the Wadia Institute of Himalayan Geology (WIHG) are used to investigate the detailed subsurface structure of the crust, the intra-crustal low-velocity layer (LVL), and the upper mantle discontinuities beneath the Kumaun–Garhwal, north-west Himalaya. The results, derived from the inversion of individual station's stacked P-receiver functions (PRFs) using the neighbourhood algorithm approach, show that the crustal thickness varies from 44 to 54 km beneath the study region. The depth of LVL observed beneath six stations from individual and stacked PRFs, varies from 9 to 24 km. The LVL zone with a high V p / V s ratio may be due to fluid or partial melt, leading to shallow seismic activity within the study region. The presence of fluid or partial melts in the LVL may be due to the shear heating, cooling, and decompression. The 2D PRF migration image depicts a thick mantle transition zone due to the elevated 410 km discontinuity with respect to the global average values predicted by the IASP91 velocity model. The present research suggests that this might be due to the colder transition zone in this region, indicating the cool underthrust Indian plate with respect to the ambient mantle has reached down to the upper mantle transition zone. | Seismological evidence for intra-crustal low velocity and thick mantle transition zones in the north-west Himalaya | 10.1007/s12040-023-02109-x |
2023-05-26 | Excellent mechanical and physical properties like high thermal resistance, high hardness, and chemical stability have encouraged the use of ceramics in various applications such as automotive engines, electronic substrates for microwave devices, dielectric materials, etc. The hard and brittle nature of these ceramics makes them difficult to cut using conventional machining due to large cutting forces as well as severe tool wear involved for such hard-to-cut material. Thus, non-contact laser machining is suitable to cut the hard and brittle ceramics. A highly focused laser beam strikes the workpiece with a high energy such that the temperature of the workpiece exceeds its boiling temperature, resulting in vaporization and ablation. In this paper, an experimental investigation of the laser cutting of 7 mm thick ceramic panels, commonly used as glazed floor tiles, is carried out using a fiber laser. The present study involves a systematic experimental investigation with the aim of evaluating the influence of the input process parameters, namely laser power, frequency, scanning speed and gas pressure on kerf widths on the top and bottom surfaces, glass formation width on the bottom surface and taper angle. Based on the experimental results, regression equations are developed to estimate the responses as functions of the laser process parameters and gas pressure. Investigations reveal that kerf widths on the top and the bottom surfaces, glass formation width, and taper angle increases with laser power and decreases with increasing scanning speed at constant gas pressure and frequency. Moreover, glass formation width increases with increasing frequency at constant laser power and gas pressure, decreases with increasing frequency at constant scanning speed and gas pressure. The optimum process parameters are also found based on minimizing the taper angle at relatively low operating energy cost by minimizing the line energy, i.e., by minimizing laser power, P and maximizing scanning speed, V . | Parametric study of laser cutting of glazed ceramic tiles | 10.1007/s40430-023-04247-1 |
2023-05-25 | Background Cyclic nucleotide-gated ion channels (CNGCs) are nonselective cation channels that are ubiquitous in eukaryotic organisms. As Ca 2+ channels, some CNGCs have also proven to be K + -permeable and involved in plant development and responses to environmental stimuli. Sugarcane is an important sugar and energy crop worldwide. However, reports on CNGC genes in sugarcane are limited. Results In this study, 16 CNGC genes and their alleles were identified from Saccharum spontaneum and classified into 5 groups based on phylogenetic analysis. Investigation of gene duplication and syntenic relationships between S . spontaneum and both rice and Arabidopsis demonstrated that the CNGC gene family in S. spontaneum expanded primarily by segmental duplication events. Many SsCNGC s showed variable expression during growth and development as well as in tissues, suggesting functional divergence. Light-responsive cis -acting elements were discovered in the promoters of all the identified SsCNGC s, and the expression of most of the SsCNGC s showed a diurnal rhythm. In sugarcane, the expression of some SsCNGC s was regulated by low-K + treatment. Notably, SsCNGC13 may be involved in both sugarcane development and its response to environmental stimuli, including response to low-K + stress. Conclusion This study identified the CNGC genes in S . spontaneum and provided insights into the transcriptional regulation of these SsCNGC s during development, circadian rhythm and under low-K + stress. These findings lay a theoretical foundation for future investigations of the CNGC gene family in sugarcane. | Genome-wide identification and expression analysis of the cyclic nucleotide-gated ion channel (CNGC) gene family in Saccharum spontaneum | 10.1186/s12864-023-09307-3 |
2023-05-24 | Rice is a major food crop in the world. Owing to the shortage of rural labor and the development of agricultural mechanization, direct seeding has become the main method of rice cultivation. At present, the main problems faced by direct seeding of rice are low whole seedling rate, serious weeds, and easy lodging of rice in the middle and late stages of growth. Along with the rapid development of functional genomics, the functions of a large number of genes have been confirmed, including seed vigor, low-temperature tolerance germination, low oxygen tolerance growth, early seedling vigor, early root vigor, resistance to lodging, and other functional genes related to the direct seeding of rice. A review of the related functional genes has not yet been reported. In this study, the genes related to direct seeding of rice are summarized to comprehensively understand the genetic basis and mechanism of action in direct seeding of rice and to lay the foundation for further basic theoretical research and breeding application research in direct seeding of rice. | Progress in the study of functional genes related to direct seeding of rice | 10.1007/s11032-023-01388-y |
2023-05-23 | Abstract The effect of photoperiod duration on efficiency of low-temperature hardening was investigated in Arabidopsis thaliana (L.) Heynh. plants, ecotype Col-0. Six-week-old plants were exposed to cold acclimation at a temperature of 2°С during 1‒5 days at photoperiods of 0, 8, and 16 h (illuminance of 200 µmol/(m 2 s)). According to survival data and leakage of electrolytes after test freezing (–6°C, 24 h), the plants exposed to cold acclimation in the dark did not show frost resistance. The plants hardened in the light (irrespective of the length of photoperiod) considerably improved their frost resistance by the end of the cold-acclimation period. Net photosynthesis/dark respiration ratio in these plants was almost two times greater than in control material (without hardening). The plants exposed to a 16-h-long photoperiod surpassed the type of treatment with 8-h-long illumination both in the highest levels of accumulation of sugars (by almost 40%) and in the rate of reaching these levels in daily dynamics of hardening. It was shown that MDA content transiently rose during the first 24 h of hardening in the light and did not change in the dark, which may point to a signal role of lipid peroxidation products upon cold acclimation. It was discovered that the photoperiod duration affected the formation rate of frost resistance in A. thaliana plants. A more prolonged operation of A. thaliana’s photosynthetic apparatus at 16-h-long photoperiod considerably accelerated the accumulation of sugars upon cold acclimation and, therefore, hastened development of frost resistance as compared with an 8-h-long photoperiod. It was concluded that rapid formation of frost resistance in A. thaliana requires a combination of low above-zero temperature and 16-h-long photoperiod. | Effect of Photoperiod Duration on Efficiency of Low-Temperature Hardening of Arabidopsis thaliana Heynh. (L.) | 10.1134/S1021443722603093 |
2023-05-23 | Abstract Freezing injury is a common abiotic stress in alpine regions. γ-Aminobutyric acid (GABA) is a ubiquitous non-protein amino acid that plays an active role in plant stress resistance. Metabonomic results have shown that the GABA content in winter wheat ( Triticum aestivum L.) “Dongnongdongmai 1” (Dn1) significantly changes with decrease in temperature. To clarify the relationship between GABA metabolism and low-temperature stress in winter wheat Dn1, we analyzed the expression of TaGAD and TaGABA-T in the tillering node under natural cooling conditions in the field. Additionally, we constructed plant overexpression vectors and introduced them into Arabidopsis thaliana to obtain stable genetic T 3 plants, which were then analyzed under low-temperature stress (–10°C). The expression of TaGAD and TaGABA-T in winter wheat Dn1 gradually increased with decrease in temperature and significantly increased with a temperature decreased from 0 to –10°C. TaGAD expression was highest at –25°C, and the expression abundance of TaGABA-T was close to –10 at –25°C. Moreover, the T 3 generation of A. thaliana overexpressing TaGAD and TaGABA-T showed stronger cold resistance than the wild-type. After low-temperature stress, the relative expression in the overexpression lines significantly increased and the relative conductivity and malondialdehyde content decreased compared to those in the wild-type; however, TaGAD -overexpressing lines were better than TaGABA-T- overexpressing lines. These results indicate that the GABA pathway can positively respond to low-temperature stress and that the overexpression of TaGAD is better than that of TaGABA-T for enhancing cold resistance. | Cloning of TaGAD and TaGABA-T from Winter Wheat and Expression Analysis in Arabidopsis thaliana | 10.1134/S1021443722602786 |
2023-05-23 | Abstract The effect of nitrogen starvation and, for the first time, low temperature, as well as their simultaneous effect, on the physiology and ultrastructure of cells of microalgae of the genus Lobosphaera (Chlorophyta, Trebouxiophyceae) was studied. Nitrogen deficiency in both strains led to a decrease in the content of chlorophyll by three times and an increase in the proportion of carotenoids by two times. A decrease in the content of both chlorophyll and carotenoids was observed at +10°C. The simultaneous effect of two factors resulted in a threefold decrease in the chlorophyll content in NAMSU 924/2 and a sixfold decrease in NAMSU (CALU) 1497; the proportion of carotenoids in both strains decreased by 1.5–2 times. Data on ultrastructural changes in cells of microalgae of the genus Lobosphaera under the influence of stress factors have been obtained. A similar nature of the response in both strains to stress conditions was noted. Nitrogen deficiency led to the accumulation of numerous lipid droplets in the cytoplasm of cells along the cell wall. Long-term incubation on a nitrogen-free medium led to the filling of the entire volume of cells with lipid droplets, disassembly of the membrane system of chloroplasts, that reduction in sizeand being located between densely lying lipid droplets. At low temperatures, the number of thylakoids decreased, while the interthylakoid space and the size of chloroplasts increased. With simultaneous exposure to nitrogen starvation and low temperature, numerous lipid droplets accumulated, the number of thylakoids decreased, the interthylakoid space and the size of the chloroplast increased, which was noted under separate exposure to stress factors. The pyrenoid in both strains did not undergo significant changes in all cases. | The effect of Low Temperature and Nitrogen Starvation on the Morphological and Physiological Characteristics of Two Strains of Green Microalgae of the Genus Lobosphaera sp. (Chlorophyta, Trebouxiophyceae) | 10.1134/S1021443722700091 |
2023-05-23 | In this paper, we initiate the study of operator local quenches in non-conformal field theories. We consider the dynamics of excited local states in massive scalar field theory in an arbitrary spacetime dimension and generalize the well-known two-dimensional CFT results. We derive the energy density, U(1)-charge density and ϕ 2 ( x )-condensate post-quench dynamics, and identify different regimes of their evolution depending on the values of the field mass and the quench regularization parameter. For local quenches in higher-dimensional free massless scalar theories, we reproduce the structure of the available holographic results. We also investigate the local quenches in massive scalar field theory on a cylinder and show that they cause an erratic and chaotic-like evolution of observables with a complicated localization/delocalization pattern. | From locality to irregularity: introducing local quenches in massive scalar field theory | 10.1007/JHEP05(2023)188 |
2023-05-22 | High-entropy alloys offer a simpler alternative to the precise balance of binary alloy designs in terms of chemical composition. Such alloys consist of at least five basic metallic elements with solute elements that have relatively similar atomic sizes, resulting in a roughly equimolar ratio. Alloys produced using this method exhibit extraordinary physical properties, attracting the attention of researchers. However, for them to be viable for industrial production, their economic value must also be reasonable. In this study, high-purity and commercial alloying elements were used to produce samples by arc melting. Structural analysis was conducted on the resulting samples, and the differences in their structural characteristics were examined through heat treatment. The high-purity high-entropy alloy samples showed a structure similar to that of the commercially pure sample before heat treatment. However, after heat treatment, it was found that different structures had formed in the commercial sample, likely due to the presence of small amounts of impurities in the content of the commercially pure alloy. | Characterization of AlCoCrFeNiVTi High Entropy Alloy Produced with Different Alloying Sources | 10.1007/s11665-023-08316-3 |
2023-05-20 | Background Regulatory T cells (Tregs) play an important role in regulation of immune response and immunologic tolerance in cancer. Gastrointestinal cancer is still a leading cause of cancer-related death in the world. This study aimed to detect Tregs in patients with gastrointestinal cancer. Methods In this study, 45 gastric cancer patients, 50 colorectal cancer patients and 50 healthy controls were enrolled. Flow cytometry was used to detect CD4 + CD25 hi CD127 low Tregs, CD4 + CD25 hi , and CD4 + cells in peripheral blood. Cytokine interleukin-10 (IL-10) and transforming growth factor-β1 (TGF-β1) in peripheral blood and in the supernatant of Tregs cultures were measured by enzyme linked immunosorbent assay. Results Compared with healthy controls, the levels of CD4 + CD25 hi CD127 low Tregs and CD4 + CD25 hi cells increased significantly in patients with gastrointestinal cancer. Patients with gastrointestinal cancer also showed a significantly increased levels of IL-10 and TGF-β1 in both peripheral blood and CD4 + CD25 hi CD127 low Tregs culture medium. Conclusion The present study firstly demonstrated that gastrointestinal patients have a compromised immune status where the CD4 + CD25 hi CD127 low Tregs, as well as levels of IL-10 and TGF-β1 are elevated. The data offered new information for understanding the immunological features of gastrointestinal patients, as well as provided new insights into approaches to develop new immunotherapies for patients with gastrointestinal cancer. | Peripheral CD4+CD25hiCD127low regulatory T cells are increased in patients with gastrointestinal cancer | 10.1186/s12876-023-02798-0 |
2023-05-20 | Background Chorioamnionitis (CAM) is a common risk factor for preterm births, resulting in several adverse outcomes. The association between infertility treatment and CAM is unclear. Therefore, this study examined the association between infertility treatment and CAM and described subsequent neonatal outcomes. Methods This population-based cohort study used data from the National Vital Statistics System Database. We included women who had a singleton live birth from January 1, 2016 to December 31, 2018. Women-infant pairs were stratified by infertility treatment, and the main outcome was a reported diagnosis of CAM in a checkbox format: clinical CAM or maternal temperature of > 38 °C. Multivariate logistic regression was used to examine the association between infertility treatment and CAM and the effect of infertility treatment on neonatal outcomes in women diagnosed with CAM. Results The final sample comprised 10,900,495 woman-infant pairs, and 1.4% received infertility treatment. Compared with the natural conception group, women receiving infertility treatment had a significantly higher risk of CAM (adjusted odds ratio [aOR] 1.772 [95% confidence interval {CI}, 1.718–1.827]). Furthermore, newborns exposed to CAM had a higher risk of very low birth weight (VLBW) (aOR, 2.083 [95% CI, 1.664–2.606], P < .001), preterm birth (aOR, 1.497 [95% CI, 1.324–1.693]; P < .001), neonatal intensive care unit admission (aOR, 1.234 [95% CI, 1.156–1.317]; P < .001), and other adverse neonatal outcomes in the infertility treatment group compared with ones conceived naturally. Conclusions This study found that women who received infertility treatment had a higher risk of CAM. And CAM deteriorated neonatal outcomes in the infertility treatment group. | Association of chorioamnionitis with infertility treatment and subsequent neonatal outcomes in the US: a population-based cohort study | 10.1186/s12884-023-05619-0 |
2023-05-19 | Background Suicide is more prevalent among disadvantaged, discriminated, and marginalised people with the majority of global suicide deaths occurring in the low-and middle-income countries (LMICs). This can be attributed to sociocultural contexts and exacerbated by access to limited resources and services that can assist with early identification, treatment, and support. Accurate information on the personal experiences of suicide is lacking, as many LMICs legislate that suicide is illegal. Methods This study aims to review the qualitative literature to explore the experiences of suicide in LMICs from the first-person perspective. Following the PRISMA-2020 guidelines, the search for qualitative literature published between January 2010 and December 2021 was undertaken. A total number of 110 qualitative articles from 2569 primary studies met the inclusion criteria. Included records were appraised, extracted, and synthesised. Results The results provide lived experience insight into suicide from those living in LMICs, including understanding variations of the causes of suicides, the impacts on others exposed to suicide, existing support systems, and prevention measures to reduce suicide among LMICs. The study offers a contemporary understanding of how people in LMIC experience suicide. Conclusions The findings and recommendations are derived from the similarities and differences within the existing knowledge base that is dominated by evidence from high-income countries. Timely suggestions for future researchers, stakeholders, and policymakers are provided. | Qualitative research in suicidology: a systematic review of the literature of low-and middle-income countries | 10.1186/s12889-023-15767-9 |
2023-05-18 | Main conclusion Through QTL-seq, QTL mapping and RNA-seq, six candidate genes of qLTG9 can be used as targets for cold tolerance functional characterization, and six KASP markers can be used for marker-assisted breeding to improve the germination ability of japonica rice at low temperature. Abstract The development of direct-seeded rice at high latitudes and altitudes depends on the seed germination ability of rice under a low-temperature environment. However, the lack of regulatory genes for low-temperature germination has severely limited the application of genetics in improving the breeds. Here, we used cultivars DN430 and DF104 with significantly different low-temperature germination (LTG) and 460 F 2:3 progeny derived from them to identify LTG regulators by combining QTL-sequencing, linkage mapping, and RNA-sequencing. The QTL-sequencing mapped qLTG9 within a physical interval of 3.4 Mb. In addition, we used 10 Kompetitive allele-specific PCR (KASP) markers provided by the two parents, and qLTG9 was optimized from 3.4 Mb to a physical interval of 397.9 kb and accounted for 20.4% of the phenotypic variation. RNA-sequencing identified qLTG9 as eight candidate genes with significantly different expression within the 397.9 kb interval, six of which possessed SNPs on the promoter and coding regions. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) completely validated the results of these six genes in RNA-sequencing. Subsequently, six non-synonymous SNPs were designed using variants in the coding region of these six candidates. Genotypic analysis of these SNPs in 60 individuals with extreme phenotypes indicated these SNPs determined the differences in cold tolerance between parents. The six candidate genes of qLTG9 and the six KASP markers could be used together for marker-assisted breeding to improve LTG. | Combined QTL-sequencing, linkage mapping, and RNA-sequencing identify candidate genes and KASP markers for low-temperature germination in Oryza sativa L. ssp. Japonica | 10.1007/s00425-023-04155-7 |
2023-05-18 | This study evaluates hydrology and hydrological extremes under future climate change scenarios. The climate change scenarios were developed from multiple Global Circulation Models (GCMs), Representative Concentration Pathway (RCP) scenarios, and statistical downscaling techniques. To ensure hydrological model robustness, the Soil Water Assessment Tool (SWAT) was calibrated and validated using the Differential Split Sample Test (DSST) approach. The model was also calibrated and validated at the multi-gauges of the watershed. Future climate change scenarios revealed a reduction in precipitation (in the order of −9.1% to 4.9%) and a consistent increase in maximum temperature (0.34°C to 4.10°C) and minimum temperature (−0.15 °C to 3.7°C) in different climate model simulations. The climate change scenarios triggered a reduction of surface runoff and streamflow and a moderate increase in evapotranspiration. Future climate change scenarios projected a decrease in high flow (Q5) and low flow (Q95). A higher reduction of Q5 and annual minimum flow is also simulated in future climate scenarios, whereas an increase in annual maximum flow is simulated in climate change scenarios developed from the RCP8.5 emission scenario. The study suggests optimal water management structures which can reduce the effect of change in high and low flows. | Hydrology and hydrological extremes under climate change scenarios in the Bosque watershed, North-Central Texas, USA | 10.1007/s11356-023-27477-1 |
2023-05-18 | Background The aim of the study was to determine the rate of cytomegalovirus virolactia in the human milk (HM) of mothers of VLBW infants, compare the CMV infection rates and the changes in CMV DNA viral load and nutrient profile among different HM preparation methods. Methods A prospective randomized controlled study was performed in infants with gestational age < 32 weeks or birth-weight < 1500 g admitted to neonatal intensive care unit of Asan Medical Center and Haeundae Paik Hospital who were given mother’s own milk. Enrolled infants were randomized into three groups according to the HM preparation methods: freezing-thawing (FT), FT + low-temperature Holder pasteurization (FT + LP), and FT + high-temperature short-term pasteurization (FT + HP). Urine CMV culture and PCR were obtained at birth and at 4, 8, and 12 weeks. HM CMV culture and PCR were obtained at birth and at 3, 6, 9, and 12 weeks. Changes in macronutrients in HM was obtained at 4 ~ 6 weeks. Results Of 564 infants, 217 mothers (38.5%) produced CMV PCR positive milk. After exclusion, a total of 125 infants were randomized into the FT (n = 41), FT + LP (n = 42), and FT + HP (n = 42) groups, whose rate of HM-acquired CMV infection was 4.9% (n = 2), 9.5% (n = 4), and 2.4% (n = 1), respectively. Out of seven CMV infected infants, two infants fed with FT + LP HM developed CMV infection- associated symptoms. Ages at diagnoses were earlier (28.5 days after birth) and at younger post conceptional age (< 32 weeks) in comparison to infants with asymptomatic CMV infection. CMV DNA viral load significantly decreased after pasturizations, especially in FT + HP group. Conclusions HM-acquired symptomatic CMV infection rate is low and its impact on clinical course was not serious in our VLBW infants. However, evidences showing poor neurodevelopmental outcome in later life, we need to generate a guideline to protect VLBW infant form HM transmitted CMV infection. Based on our small sized study, we did not find any superiority in pasteurizing HM with frequently used LP in comparison to frozen or HP HM. More research is needed to determine the method and duration of pasteurization to reduce the HM-acquired CMV infection. | Prevention of human milk-acquired cytomegalovirus infection in very-low-birth-weight infants | 10.1186/s12887-023-04044-8 |
2023-05-18 | Various steep-slope devices based on novel structures and mechanisms garnered considerable attention for their potential in ultra-low power logic applications. In this work, a novel steep-slope negative quantum capacitance field-effect transistor (NQCFET) with molybdenum disulfide (MoS 2 )-integrated gate stack was realized by theoretical analysis and experimental evaluation. By combining the MoS 2 equivalent capacitance model calibrated with experimental results, the NQCFET device model is further established. The results demonstrated that the optimized MoS 2 -integrated NQCFET can achieve a subthreshold swing (SS) of sub-60 mV/dec over a current range of 5 decades, with the minimum SS reaching 29 mV/dec, indicating the remarkable potential of MoS 2 -integrated NQCFETs for ultra-low power applications. | A novel negative quantum capacitance field-effect transistor with molybdenum disulfide integrated gate stack and steep subthreshold swing for ultra-low power applications | 10.1007/s11432-023-3763-3 |
2023-05-18 | Background This study aims to identify the impact on the reaction while the clasp and sling fibers of the human lower esophageal sphincter are under the electrical field stimulation, by adding lysophosphatidic acid receptor subtypes antagonist. Methods Between March 2018 to December 2018, muscle strips were isolated from 28 patients who underwent esophagectomy for mid-third esophageal carcinomas. Muscle tension measurement technique in vitro and electrical field stimulation were used to examine the effects of selective lysophosphatidic acid receptor antagonist on the clasp and sling fibers of human lower esophageal sphincter. Results The optimal frequency of frequency-dependent relaxation in clasp fibers and contraction in sling fibers induced by electrical field stimulation is 64 Hz and 128 Hz respectively. The selective lysophosphatidic acid 1 and 3 receptor antagonist produced no significant difference in the frequency-dependent relaxation in clasp fibers and contraction in sling fibers induced by the electrical field stimulation ( P > 0.05). Conclusion The electrical field stimulation induced a frequency-dependent relaxation in clasp fibers and contraction in sling fibers. The lysophosphatidic acid 1 and 3 receptors are not involved in the response of clasp and sling fibers of the human lower esophageal sphincter induced by the electrical field stimulation. | The contribution of lysophosphatidic acid receptors in the response of human lower esophageal sphincter under the electrical field stimulation | 10.1186/s12876-023-02738-y |
2023-05-17 | In this paper, the ferrite grain size was controlled by two annealing methods, which can affect the low-temperature toughness of ferrite nodular cast iron. The annealing temperature ranged from 720 to 750 °C, and one annealing method consisted of constant temperature heating with temperature controlled to ± 1 °C. The other method employed cyclic heating, with a temperature change of 19 ( + 14, − 5) °C and a period of 450 s. The change law of ferrite grain size under low temperature annealing and the effect of ferrite grain size on low-temperature impact toughness were studied. The conditions under which the superheated ferrite does not transform into austenite were determined. The mechanism by which coarse ferrite favors high toughness in nodular cast iron at low temperatures was discussed. Nodular cast iron with tensile strength of 392 MPa, yield strength of 206 MPa, elongation of 26% and impact energy of 13.5 J at − 70 °C was obtained. | Study on the Control Method of Ferrite Grain Size of Nodular Cast Iron and Its Effect on Low-Temperature Impact Toughness | 10.1007/s11665-023-08172-1 |
2023-05-16 | Background Colorectal tumor differentially expressed (CRNDE) is specifically expressed in human brains and is the most highly expressed lncRNA in gliomas. Nevertheless, its implications in low grade glioma (LGG) are still indistinct. This study presented systematic analyses of CRNDE in LGG biology. Methods We retrospectively retrieved TCGA, CGGC and GSE16011 LGG cohorts. Survival analysis was conducted for evaluating the prognostic significance of CRNDE in LGG. A CRNDE-based nomogram was established, and its predictive performance was verified. Signaling pathways underlying CRNDE were analyzed through ssGSEA and GSEA approaches. The abundance of immune cells and activity of cancer-immunity cycle were estimated with ssGSEA approach. Immune checkpoints, HLAs, chemokines, and immunotherapeutic response indicators (TIDE, and TMB) was quantified. U251 and SW1088 cells were transfected with specific shRNAs of CRNDE, and flow cytometry (apoptosis) and western blot (β-catenin and Wnt5a) assays were conducted. Results Up-regulated CRNDE was found in LGG, and was linked to unfavorable clinical outcomes. The CRNDE-based nomogram enabled to accurately predict patients’ prognosis. High CRNDE expression was linked to more genomic variations, activity of tumorigenic pathways, tumor immunity (increase in infiltration of immune cells, expression of immune checkpoints, HLAs and chemokines, and cancer-immunity cycle), and therapeutic sensitivity. CRNDE knockdown mitigated malignant phenotypes of LGG cells. Conclusions Our study determined CRNDE as a novel predictor for patient prognosis, tumor immunity and therapeutic response in LGG. Assessment of CRNDE expression is a promising approach for predicting the therapeutic benefits of LGG patients. | Implications of CRNDE in prognosis, tumor immunity, and therapeutic sensitivity in low grade glioma patients | 10.1186/s12935-023-02930-w |
2023-05-16 | The present study aims to reveal horizontal sporadic E (Es) movements driven by atmospheric diurnal/semi-diurnal tides using a three-dimensional (3D) ionospheric model. Horizontal Es movements have been investigated since the mid-twentieth century, using a variety of 1D/2D observational techniques. However, there are no comprehensive studies that explain the different results asserted by the observations. Herein, we performed 3D Es simulations at mid- and low-latitudes. This is the first study to investigate horizontal Es movements from a 3D perspective. We found that the Es layers are constrained at the zonal-wind shear nodes above $$\sim$$ ∼ 110 km, but transported by horizontal winds below $$\sim$$ ∼ 110 km. The Es layers that descend with the downward tidal phases move southward. The descending Es layers move westward as they lag behind the zonal-wind shear nodes. The Es layers that stagnate at $$\sim$$ ∼ 100 km are transported by the semi-diurnal tides. In general, the descending and stagnating Es layers do not move eastward. This is because the Es layers diffuse vertically in the eastward/northward wind region or in the early stage of formation in the eastward/southward wind region. The horizontal Es movement tendency in the simulations agreed with and provided a general explanation for previous observations. Graphic Abstract | Simulation of horizontal sporadic E layer movement driven by atmospheric tides | 10.1186/s40623-023-01837-0 |
2023-05-15 | The effect of low-energy Ar + ion irradiation on the work function of stainless steel AISI 304L (SS-304L) was studied by varying energy and fluence of Ar + ion. The irradiation of Ar + ions on stainless steel creates several vacancies in the target material which resulted a change in work function. The retarding field diode method was used for the measurement of work function. Results reveal work function decreases with an increase in ion energy (for fixed ion fluence) of irradiated Ar + ion. Furthermore, it was observed that at varying ion fluence (for fixed ion energy) the decrease in work function value was more prominently, but at higher fluence, it again increases. In both (energy and fluence) cases of irradiation, the displacement per atom (DPA) in the material has been estimated with the stopping range using the SRIM-2013.00 program and is correlated with the experimental observation. Overall, the maximum work function was observed to be decreased by ~ 7.28% relative to the pristine sample in the case of fluence variation keeping the energy constant at 30 keV. The results indicate that low-energy ion irradiation can be utilized for work function modulation of materials and can be optimized by controlling ion fluence. The results are useful for further understanding of corrosion rate of materials and the data are extremely important for various nuclear reactors, where these materials are used. | Effect of low energy argon ion irradiation on work function of AISI 304L stainless steel | 10.1007/s00339-023-06682-2 |
2023-05-15 | In this work, a series of hypercrosslinked polymers of intrinsic microporosity (HCP-PIMs), namely nitro-triptycene (TRIP-NO 2 ), amino-triptycene (TRIP-NH 2 ), sulfonated-triptycene (TRIP-SO 3 H) and hydrocarbon-triptycene (TRIP-HC), are employed for the adsorption of organic dyes from wastewater. The materials show the efficient removal of cationic (malachite green, MG) and anionic (methyl orange, MO) dyes. The adsorption parameters herein investigated include the initial pH, the adsorbate concentration and the contact time, with the aim to elucidate their effect on the adsorption process. Furthermore, the adsorption kinetic and isotherms are studied, and the findings suggest the results fit well with pseudo-second-order kinetics and Langmuir model. The reported maximum adsorption capacity is competitive for all the tested polymers. More specifically, TRIP-SO 3 H and TRIP-HC exhibit adsorptions of ~ 303 and ~ 270 mg g −1 for MG and MO, respectively. The selectivity toward cationic and anionic dyes is assessed by mixing the two dyes, and showing that TRIP-HC completely removes both species, whereas TRIP-NO 2 , TRIP-NH 2 and TRIP-SO 3 H show an enhanced selectivity toward the cationic MG, compared to the anionic MO. The effect of the type of water is assessed by performing ultrasonic-assisted adsorption experiments, using TRIP-SO 3 H and TRIP-HC in the presence of either tap or seawater. The presence of competing ions and their concentrations is evaluated by ICP-MS. Our study shows that tap water does not have a detrimental effect on the adsorption of both polymers, whereas, in the presence of seawater, the performance of TRIP-HC toward MO proved to be more stable than MG with TRIP-SO 3 H, which is probably due to a larger concentration of competing ions. Comparison between ultrasonic-assisted and magnetic stirring adsorption demonstrates that the former exhibits a greater efficiency. This seems due to a more rapid mass transfer, driven by the formation of high velocity micro-jets, acoustic microstreaming and shock waves, at the polymer surface. Reusability studies show a good stability up to five adsorption–desorption cycles. | Ultrasonic-assisted removal of cationic and anionic dyes residues from wastewater using functionalized triptycene-based polymers of intrinsic microporosity (PIMs) | 10.1007/s13201-023-01935-0 |
2023-05-14 | In this article, a simulation of surface plasmon resonance (SPR) based Al-doped ZnO (AZO) coated long-range low refractive index detections in infrared range sensor by the finite element method is presented. Plasmonic material Al-doped ZnO is used for SPR conditions in the desired range. The effects of AZO layer thickness on resonance wavelength, confinement loss, and sensitivity of the proposed sensor are examined for different analyte refractive indices. We have optimized coated AZO layer thickness of 90 nm and width of 124.70 µm in our work. The proposed infrared sensor has achieved refractive index sensitivity 2000–16,000 nm/RIU, and the resolution $$5.00\times {10}^{-5}-6.25\times {10}^{-6}\, \mathrm{RIU}$$ 5.00 × 10 - 5 - 6.25 × 10 - 6 RIU for the analyte’s refractive index range from 1.23 to 1.37. The proposed sensor may be utilized for detecting low refractive index organic chemicals, biomedical, and liquid foods and may also be used in other sensing applications. | Al-doped ZnO based long range optical fibre sensor for efficient low refractive index detection | 10.1007/s11082-023-04896-5 |
2023-05-14 | Background Low-grade gliomas (LGG) are a type of brain tumor that can be lethal, and it is essential to identify genes that are correlated with patient prognosis. In this study, we aimed to use CRISPR-cas9 screening data to identify key signaling pathways and develop a genetic signature associated with high-risk, low-grade glioma patients. Methods The study used CRISPR-cas9 screening data to identify essential genes correlated with cell survival in LGG. We used RNA-seq data to identify differentially expressed genes (DEGs) related to cell viability. Moreover, we used the least absolute shrinkage and selection operator (LASSO) method to construct a genetic signature for predicting overall survival in patients. We performed enrichment analysis to identify pathways mediated by DEGs, overlapping genes, and genes shared in the Weighted correlation network analysis (WGCNA). Finally, the study used western blot, qRT-PCR, and IHC to detect the expression of hub genes from signature in clinical samples. Results The study identified 145 overexpressed oncogenes in low-grade gliomas using the TCGA database. These genes were intersected with lethal genes identified in the CRISPR-cas9 screening data from Depmap database, which are enriched in Hippo pathways. A total of 19 genes were used to construct a genetic signature, and the Hippo signaling pathway was found to be the predominantly enriched pathway. The signature effectively distinguished between low- and high-risk patients, with high-risk patients showing a shorter overall survival duration. Differences in hub gene expression were found in different clinical samples, with the protein and mRNA expression of REP65 being significantly up-regulated in tumor cells. The study suggests that the Hippo signaling pathway may be a critical regulator of viability and tumor proliferation and therefore is an innovative new target for treating cancerous brain tumors, including low-grade gliomas. Conclusion Our study identified a novel genetic signature associated with high-risk, LGG patients. We found that the Hippo signaling pathway was significantly enriched in this signature, indicating that it may be a critical regulator of tumor viability and proliferation in LGG. Targeting the Hippo pathway could be an innovative new strategy for treating LGG. | CRISPR-cas9 screening identified lethal genes enriched in Hippo kinase pathway and of predictive significance in primary low-grade glioma | 10.1186/s10020-023-00652-3 |
2023-05-12 | In this work, membrane fouling represented as the time-to-filter (TTF) was investigated in a function of current density (ranging from 0.3 to 1.5 mA/cm 2 ) and temperature (from 8 to 20 °C). Settling characteristics, defined as sludge volume index (SVI), were also assessed. Under low temperatures, activated sludge from electro-bioreactors revealed excellent settling and filtration properties at several combinations of low periodic current density (CD) experiments. For instance, after a 72-h electrokinetic (EK) operation at a CD of 0.3 mA/cm 2 and a temperature of 8 °C, TTF, SVI, mixed liquor suspended solids (MLSS), mixed liquor volatile suspended solids (MLVSS), ζ-potential, mean particle-size distribution (PSD), soluble microbial products (SMPs), and extracellular polymeric substances (EPSs) were 4.2 min, 53 mL g −1 , 4000 mg L −1 , 3200 mg L −1 , 12 to − 20 mV, 57.82 μm, 17.26 mg L −1 , and 13.9 mg gVSS −1 , respectively. Such improvements in both filterability and settleability of activated sludge and then potential membrane performance could be attributed to a change in the floc size and structure of activated sludge by adequate CD field operation. Nevertheless, a CD of 1.5 mA/cm 2 with a shorter resting time (i.e., 60 s ON/60 s OFF) exhibited poor filterability compared to other exposure regimes because of the elevated no growth associated SMP products. Overall, this research provides a chemical-free electrokinetic (EK) approach to improve the physicochemical and biological properties of the sludge and reduce membrane fouling at even low-temperature environments. This study demonstrated that the technological parameters of a membrane electro-bioreactor (MEBR) could be applied to low temperature sewage. | Effects of current density on fouling-related properties of sludge in an electro-bioreactor at low-temperature conditions | 10.1007/s13399-023-04199-5 |
2023-05-12 | Main conclusion Soil water content only affected regeneration time, whereas the NSC content was related to the success of alfalfa regeneration. Abstract Non-structural carbohydrates (NSCs) are important factors influencing the overwintering and regeneration of alfalfa. In this study, we analyzed eight in-situ samplings at three depths of coarse roots (crown, 20 and 40 cm depths) during the overwintering period and assessed the dynamic change and allocation of root NSCs under three irrigation frequencies (irrigation once every second day/4 days/8 days). Primary results showed that: (i) before cold acclimation, irrigation once every second day was beneficial to the accumulation of soluble sugars and starch in crown tissues, which would be maintained until the following spring and accelerate the regeneration time of alfalfa; (ii) during the overwintering process, the soluble sugars and starch contents in the crown were significantly higher than those in deeper roots, and there was an asynchronous effect caused by the change in soluble sugars and starch among roots at three depths; and (iii) the change trend of soluble sugar and starch contents was consistent with that of semi-lethal temperature, and there was a significant negative correlation between the content of soluble sugar ( R 2 = 0.8046) and starch ( R 2 = 0.6332) and the semi-lethal temperature. This study demonstrated that NSCs are the key driver of cold tolerance and regeneration under the three irrigation frequencies evaluated. Our results provide further insight into the allocation of NSCs in winter. This improved understanding of the mechanism of overwintering will allow for improved water management of alfalfa in high latitude areas. | Non-structural carbohydrates contributed to cold tolerance and regeneration of Medicago sativa L. | 10.1007/s00425-023-04154-8 |
2023-05-12 | Purpose We aimed at determining whether the load–velocity relationship of the Smith machine concentric-back squat differs between sexes and persons with different levels of strength. Methods Thirty-two participants (16 males: 23.3 ± 3.8 years and 16 females: 26.1 ± 2.7 years) were included. Load and mean concentric velocity (MCV) were obtained individually during an incremental test (30–90% one-repetition maximum—1RM). Results We obtained strong linear relationships between the individual MCV and relative load ( $${R}^{2}>$$ R 2 > 0.95). Overall, relatively strong persons reached faster MCVs throughout the full range of relative loads (effect size [ES]: 0.48–0.93), except at 1RM. We also obtained steeper slopes and higher velocity intercepts (y intercepts) in relatively strong participants (ES: 0.05 and 0.83, respectively; p < 0.01). Finally, we found that males attained steeper load–velocity relationships (ES favoring relatively strong and weak males: 2.8 and 1.4, respectively) and higher velocity intercepts (ES favoring relatively strong and weak males: 2.0 and 1.0, respectively) than females ( p < 0.0001). Conclusion MCV can be used to estimate relative load on the Smith machine concentric-back squat in males and females with different levels of muscle strength; however, the load–velocity relationship is affected by muscle strength and sex. Therefore, the extraction of individual load–velocity relationships is advisable instead of computing group estimations. | Influence of sex and strength differences on the load–velocity relationship of the Smith-machine back squat | 10.1007/s11332-023-01069-5 |
2023-05-09 | Background The role of pain sensitivity in the development and maintenance of chronic pain states, impaired executive functioning, and patient recovery is being investigated. Conditioned pain modulation (CPM) is widely used to measure musculoskeletal pain associated with central sensitization (CS). Despite the recommendations of many reviews and clinical practice guidelines that exercise programs reduce pain and disability, the overall confidence in these results is considered “critically low.” The “active ingredient” of exercise programs and the dominant factor influencing CPM remain largely unknown. The objectives of this trial are to determine: • If different exercises cause different results on the CPM in a subgroup of people with chronic low back pain (CLBP) who are labeled as having CS pain, • If a program of exercise interventions for 12 weeks would alter executive functioning, quality of life (QoL), disability, and pain in persons with CLBP. • The relationship between patient characteristics, executive functions, CPM, and QoL Methods The trial is a randomized, controlled, multi-center study with four experimental groups and one healthy control group. Both the researchers and the people in the study will be blinded to the results. This paper describes the protocol for a trial examining the effects of 12-week individualized, twice-weekly exercise sessions lasting 30 to 60 min in persons with CLBP, who are positive for CS. Participants will be randomized to receive either patient education with motor control exercises (MCE), superficial strengthening (SS), aerobic exercises (AE), or patient education alone. Another group comprised of healthy volunteers will serve as controls. The primary outcomes are changes in CPM outcomes as measured by the cold pressor test (CPT). The secondary objectives are to evaluate executive functioning, pain, disability, quality of life, and spine muscle strength. The outcomes will be measured at 3 months and at a 6-month follow-up. Discussion The outcomes of the study will help in gaining more information and evidence about exercise-induced analgesia from the perspective of CPM. Measuring exercise outcomes will aid in scientifically prescribing exercise prescriptions in people with CLBP. The study outcomes will also assist in identifying the characteristics of individuals who will respond or respond indifferently to exercises. Investigating the relationship between the study’s various outcomes could provide information for future trials. Trial registration Clinical Trials Registry of India (CTRI) identifier: CTRI/2022/03/041143. Registered on 16 March 2022. | Effectiveness of motor control exercise, aerobic walking, and muscle strengthening programs in improving outcomes in a subgroup of population with chronic low back pain positive for central sensitization: a study protocol for a randomized controlled trial | 10.1186/s13063-023-07316-x |
2023-05-09 | Neuropathic pain (NP) following spinal cord injury (SCI) often lasts for a long time and causes a range of problems that reduce the quality of life. Current treatments are not generally effective; however, photobiomodulation therapy (PBMT) has made some progress in this area. Due to the novelty of this treatment, standard therapeutic protocols have not yet been agreed upon. In the present study, we compare the analgesic effect of two PBMT protocols (2 and 4 weeks of radiation). A total of thirty-two adult male Wistar rats were divided into four groups: control, SCI, 2 W PBMT, and 4 W PBMT. SCI was induced by an aneurism clip and PBMT used a 660-nm, initiated 30 min post-SCI, and continued daily for 2 or 4 weeks. Functional recovery, hyperalgesia, and allodynia were measured weekly. At the end of the study, the Gad65, interleukin 1-alpha (IL1α), interleukin 10 (IL10), IL4, and purinergic receptor (P2xR and P2yR) expressions were measured. Data were analyzed by Prism6. The results showed PBM irradiation for 2 and 4 weeks had the same effects in improving hyperalgesia. In the case of allodynia and functional recovery, 4 W PBMT was more effective ( p <0.01). 4 W PBMT increased the Gad65 expression ( p <0.001) and reduced P2Y4R ( p <0.05) compared to SCI animals. The effects of 2 and 4 W PBMT were the same for IL1α, IL10, and P2X3 receptors. 4 W PBMT was more effective in reducing the complications of SCI such as pain and disability. PBMT therapy is an effective method aimed at immune system function modulation to reduce NP and motor dysfunction. | Time-dependent photobiomodulation management of neuropathic pain induced by spinal cord injury in male rats | 10.1007/s10103-023-03722-4 |
2023-05-08 | Recently, the Doppler shifts from Low Earth Orbit (LEO) satellites have been used to augment GNSS and provide navigation services. We propose a Doppler-only point-solution algorithm for GNSS-like navigation systems operated in LEO. The proposed algorithm can simultaneously estimate the receiver clock drift, position and velocity. Then, we analyze the main error sources in Doppler positioning. To achieve the meter-level positioning accuracy, the satellite position and velocity errors should be within several meters and several centimeters per second, respectively. The ionospheric delay rates of C-band signal will cause about 1 m error in Doppler positioning, which can be eliminated using the ionosphere-free combination. The Doppler positioning accuracy will deteriorate sharply by dozens of meters if there are no corrections for the tropospheric errors. Subsequently, we analyze the Doppler positioning performance. The undifferenced Doppler positioning accuracy is at meter level, which is comparable with the pseudorange-based positioning in GNSS. To ensure convergence in the LEO-based Doppler positioning, the initial receiver position error should be less than 300 km when the satellites orbit is at an altitude of 550 km. | Revisiting Doppler positioning performance with LEO satellites | 10.1007/s10291-023-01466-w |
2023-05-06 | Background Breast milk (BM) is a dynamic fluid that varies over time and between women. The variations in BM components are most likely associated with maternal diet quality. This study aimed to assess adherence to a low carbohydrate dietary (LCD) pattern with oxidative stress markers of BM characteristics and infants’ urine. Materials and methods In this cross-sectional study 350 breastfeeding mothers and their infants were recruited. BM samples were collected from mothers, and urine specimens were obtained from each infant. To evaluate LCD scores, subjects were divided into 10 deciles according to the percent of energy obtained from carbohydrates, proteins, and fats. Determination of total antioxidant activity was conducted using the ferric reducing antioxidant power (FRAP), 2, 2′-diphenyl-1-picrylhydrazyl (DPPH), thiobarbituric acid reactive substances (TBARs), and Ellman’s assay. Biochemical assays of samples including calcium, total protein, and triglyceride level were also performed using commercial kits. Results Participants with the greatest LCD pattern adherence were placed into the last quartile (Q4), and those with the minimum LCD were in the first quartile (Q1). Individuals in the highest LCD quartile had significantly higher levels of milk FRAP, thiol, and protein, as well as infant urinary FRAP and lower milk MDA levels than those in the lowest quartile. Multivariate linear regression analyses indicated that higher score of the LCD pattern was associated with a higher level of milk thiol, protein, and lower level of milk MDA ( p < 0.05). Conclusion Our findings show that adherence to a LCD, as defined by a low level of carbohydrates in daily food intake, is linked with improved BM quality and markers of oxidative stress in infant urine. | Association between adherence to a low carbohydrate dietary (LCD) pattern with breast milk characteristics and oxidative markers in infants’ urine: a cross-sectional study | 10.1186/s41043-023-00381-7 |
2023-05-06 | Background Acute lower respiratory tract infections (ALRTIs) among children under five are still the leading cause of mortality among this group of children in low and middle-income countries (LMICs), especially countries in sub-Saharan Africa (SSA). This scoping review aims to map evidence on prevalence and risk factors associated with ALRTIs among children under 5 years to inform interventions, policies and future studies. Methods A thorough search was conducted via four main databases (PubMed, JSTOR, Web of Science and Central). In all, 3,329 records were identified, and 107 full-text studies were considered for evaluation after vigorous screening and removing duplicates, of which 43 were included in this scoping review. Findings Findings indicate a high prevalence (between 1.9% to 60.2%) of ALRTIs among children under five in SSA. Poor education, poverty, malnutrition, exposure to second-hand smoke, poor ventilation, HIV, traditional cooking stoves, unclean fuel usage, poor sanitation facilities and unclean drinking water make children under five more vulnerable to ALRTIs in SSA. Also, health promotion strategies like health education have doubled the health-seeking behaviours of mothers of children under 5 years against ALRTIs. Conclusion ALRTIs among children under five still present a significant disease burden in SSA. Therefore, there is a need for intersectoral collaboration to reduce the burden of ALRTIs among children under five by strengthening poverty alleviation strategies, improving living conditions, optimising child nutrition, and ensuring that all children have access to clean water. There is also the need for high-quality studies where confounding variables in ALRTIs are controlled. | Acute lower respiratory infections among children under five in Sub-Saharan Africa: a scoping review of prevalence and risk factors | 10.1186/s12887-023-04033-x |
2023-05-04 | Background In wheat, nitrogen (N) remobilization from vegetative tissues to developing grains largely depends on genetic and environmental factors. The evaluation of genetic potential of crops under limited resource inputs such as limited N supply would provide an opportunity to identify N-efficient lines with improved N utilisation efficiency and yield potential. We assessed the genetic variation in wheat recombinant inbred lines (RILs) for uptake, partitioning, and remobilization of N towards grain, its association with grain protein concentration (GPC) and grain yield. Methods We used the nested association mapping (NAM) population (195 lines) derived by crossing Paragon (P) with CIMMYT core germplasm (P × Cim), Baj (P × Baj), Watkins (P × Wat), and Wyalkatchem (P × Wya). These lines were evaluated in the field for two seasons under limited N supply. The plant sampling was done at anthesis and physiological maturity stages. Various physiological traits were recorded and total N uptake and other N related indices were calculated. The grain protein deviation (GPD) was calculated from the regression of grain yield on GPC. These lines were grouped into different clusters by hierarchical cluster analysis based on grain yield and N-remobilization efficiency (NRE). Results The genetic variation in accumulation of biomass at both pre- and post-anthesis stages were correlated with grain-yield. The NRE significantly correlated with aboveground N uptake at anthesis (AGNa) and grain yield but negatively associated with AGN at post-anthesis (AGNpa) suggesting higher N uptake till anthesis favours high N remobilization during grain filling. Hierarchical cluster analysis of these RILs based on NRE and yield resulted in four clusters, efficient (31), moderately efficient (59), moderately inefficient (58), and inefficient (47). In the N-efficient lines, AGNa contributed to 77% of total N accumulated in grains, while it was 63% in N-inefficient lines. Several N-efficient lines also exhibited positive grain protein deviation (GPD), combining high grain yield and GPC. Among crosses, the P × Cim were superior and N-efficient, while P × Wya responded poorly to low N input. Conclusions We propose that traits favouring pre- or post-anthesis biomass accumulation and pre-anthesis N uptake may be targeted for breeding to improve grain-yield under limited N. The lines with positive GPD, a first report of genotype-dependent GPD associated with both AGNpa and AGNa in wheat, may be used as varieties or genetic resources to improve grain yield with high GPC for sustainable development under limited N conditions. | Nitrogen uptake and remobilization from pre- and post-anthesis stages contribute towards grain yield and grain protein concentration in wheat grown in limited nitrogen conditions | 10.1186/s43170-023-00153-7 |
2023-05-04 | Background Radiation damage and the cellular response has been studied in various direction, however, the synergic effects of radiation damage with environmental pollution on cells or tissues remained poorly understood. In particular, gene and pathway regulation by low-dose radiation exposure remains unclear. Dust and air pollution in Asian countries contains metal oxide and titanium dioxide nanoparticles (TiO 2 NPs), which exacerbate respiratory distress. Objective To explore the synergic injury of radiation damage with air pollution, we examined the effects of low-dose-rate radiation with TiO2NPs on pulmonary response in mice. Results Thirty-six mice (C57bl/6) were divided into six groups: sham, 0.1 Gy, 0.3 Gy, TiO 2 NPs, TiO 2 NPs + 0.1 Gy, and TiO 2 NPs + 0.3 Gy group. Mice were irradiated at a low-dose-rate at a dose of 0.1 Gy (0.182 mGy/h) and 0.3 Gy (0.554 mGy/h) for 24 days and exposed to TiO 2 NPs by intranasal injection at a dose of 0.1 mg daily for 4 days (from day 21 to 24). The combination of low-dose-rate radiation and TiO 2 NPs caused significantly more pulmonary inflammation via MAPK phosphorylation in mice than did each stimulus alone. Conclusion We conclude that while exposure to each of these two distinct stimuli alone does not cause notable lung damage, they may potentially cause lung damage when combined owing to their synergistic effects. Therefore, we should pay attention to the possible combined effects of low-dose radiation and exposure to TiO 2 NPs, considering their potential danger in patients with respiratory problems. | Low-dose-rate gamma radiation aggravates titanium dioxide nanoparticle-induced lung injury in mice | 10.1007/s13273-023-00353-2 |
2023-05-03 | The catalytic conversion of biomass platform chemicals using abundant non-noble metal nanocatalysts is a challenging topic. Here, high-density cobalt oxide nanoparticles loaded on biomass-derived porous N-doped carbon (NC) was fabricated by a tandem hydrothermal pyrolysis and mild nitrate decomposition process, which is a green and cheap preparation method. The Co 3 O 4 nanoparticles with the average size of 12 nm were uniformly distributed on the porous NC. The nanocomposites also possessed large surface area, high N content, good dispersibility in isopropanol, and furfural absorbability. Due to these characteristics, the novel cobalt nanocatalyst exhibited high catalytic activity for producing furfuryl alcohol, yielding 98.7% of the conversion and 97.1% of the selectivity at 160 °C for 6 h under 1 bar H 2 . The control experiments implied that both direct hydrogenation and transfer hydrogenation pathways co-existed in the hydrogenation reaction. The excellent catalytic activity of Co 3 O 4 @NC was attributed to the cooperative effects of porous NC and Co 3 O 4 nanoparticles. This approach provides a new idea to design effective high-density nonnoble metal oxide nanocatalysts for hydrogenation reactions, which can make full use of sustainable natural biomass. | Robust Co3O4 nanocatalysts supported on biomass-derived porous N-doped carbon toward low-pressure hydrogenation of furfural | 10.1007/s11706-023-0645-9 |
2023-05-01 | Acetone is a solvent used in many laboratories and factories. Serious problems will occur when it is exposed to the environment. Therefore, a new design hydrophobicity bimetallic metal material (10-Fe 1 Mn 1 -USY) was prepared for acetone adsorption under conditions of high humidity. Hydrophobic Y type zeolite was used to prepare bimetallic metal materials and the effect of different operating parameters (including different material, humidity, temperature, pollutant concentration, residence time, and regeneration) on the efficiency of acetone treatment was examined. Isothermal adsorption model, kinetics and thermodynamic model analysis were also used to establish the reaction mechanism. The 10-Fe 1 Mn 1 -USY material has good adsorption capacity (133 mg g −1 ) for acetone under a relative humidity of 50%. The main factors affecting the adsorption capacity are the contact angle, hydrophobicity, specific surface area, and Si/Al of the material. The isothermal adsorption and the kinetic adsorption behavior of 10-Fe 1 Mn 1 -USY material for acetone are more suitable for the Temkin isotherm adsorption model and the pseudo-first-order kinetic model. The adsorption of acetone by 10-Fe 1 Mn 1 -USY material is dominated by intra-particle diffusion. According to the thermodynamic analysis results, the adsorption behavior of 10-Fe 1 Mn 1 -USY material for acetone is a type of physical adsorption, and a spontaneous and non-sequential reaction. | Specifically designed 10-Fe1Mn1-USY hydrophobicity material for acetone adsorption under high humidity condition | 10.1186/s42834-023-00173-y |
2023-05-01 | The aim of this study is to appraise the potential of calcium sulfoaluminate (CSA) cement-based grouts in simulated permafrost environments. The hydration and performance of CSA cement-based grouts cured in cold environments (10, 0, and −10 °C) are investigated using a combination of tests, including temperature recording, X-ray diffraction (XRD) tests, thermogravimetric analysis (TGA), and unconfined compressive strength (UCS) tests. The recorded temperature shows a rapid increase in temperature at the early stage in all the samples. Meanwhile, results of the TGA and XRD tests show the generation of a significant quantity of hydration products, which indicates the rapid hydration of CSA cement-based grouts at the early stage at low temperatures. Consequently, the CSA cement-based grouts exhibit remarkably high early strength. The UCS values of the samples cured for 2 h at −10, 0, and 10 °C are 6.5, 12.0, and 12.3 MPa, respectively. The UCS of the grouts cured at −10, 0, and 10 °C increases continuously with age and ultimately reached 14.9, 19.0, and 30.6 MPa at 28 d, respectively. The findings show that the strength of grouts fabricated using CSA cement can develop rapidly in cold environments, thus rendering them promising for permafrost applications. | Appraising the potential of calcium sulfoaluminate cement-based grouts in simulated permafrost environments | 10.1007/s11709-023-0950-5 |
2023-05-01 | The conductivity of the electrolyte and the kinetics of Li + inside lithium-ion batteries (LIBs) will decrease at low temperatures, which may promote the formation of lithium dendrite. The growing of lithium dendrites will penetrate the separator, and cause the internal short circuits and thermal runaway of cells. Thus, battery preheating is essential to improve the safety of LIBs. To investigate the temperature changes of battery during discharging and preheating at low temperatures, the electro-thermal model and the preheating model of LIBs at low temperature are established and verified based on the second-order equivalent circuit model. The internal resistance of battery decreases with the increase of temperature. Moreover, a battery module with polyimide flexible heating film is proposed, and the heating films are arranged on both sides of the battery symmetrically. When the power of heating films is 1 W, 3 W, and 5 W, it takes 395 s, 190 s and 126 s to preheat the battery temperature from − 10°C to 25°C, respectively. Additionally, different heating powers can be arranged in the heating process to reduce the heating time and temperature difference of battery. The research in this study contributes to the preheating of LIBs in cold regions, and has certain reference value. | Preheating Performance by Heating Film for the Safe Application of Cylindrical Lithium-ion Battery at Low Temperature | 10.1007/s10694-022-01251-0 |
2023-05-01 | Due to its excellent piezoelectric characteristics and Curie temperatures, PZT-5H piezoelectric ceramics are perfect for creating low-temperature co-fired multilayer devices. The effects of Bi 2 O 3 doping on the low-temperature sintering properties of PZT-5H ceramic powder were investigated in this work. When the mass fraction of Bi 2 O 3 is 0.9%, PZT-5H ceramics can be completely sintered at 850°C. In addition, the chemical composition exhibits the best electrical properties at this doping level and lies at the morphological phase boundary (MPB). The property is as follows: d 33 = 504pC/N, tan δ = 0.0296, k p = 0.653, Q m = 30.983, and T c = 230°C. A multilayer piezoelectric ceramic actuator was created in this work to better demonstrate the real-world applications of using this material in low-temperature co-fired devices. The multilayer piezoelectric actuator’s characterization revealed that the material was tightly attached to the Ag electrode, and that there was minimal Ag diffusion at the bond, with satisfactory co-firing matching. At a drive voltage of 600 V, the multilayer actuator produced a displacement of 2.18 μ m and a strain value of 0.109%. This showed that it was feasible to create multilayer piezoelectric ceramic actuators with this material, and that it provides a new alternative material for creating other multilayer piezoelectric ceramic devices. | Low-Temperature Sintering Properties of Bi2O3 Doped PZT-5H Piezoelectric Ceramics | 10.1007/s11664-023-10312-1 |
2023-05-01 | Polydicyclopentadiene (PDCPD) is a thermosetting resin material with excellent comprehensive mechanical properties, which is obtained from DCPD by ring-opening transfer curing. PDCPD has excellent physical properties and stable chemical properties, and its characteristics of light weight and high strength are very prominent. It is used for rapid prototyping of lightweight products, such as commercial car roof guide cover, side skirt board, mecha cover and other car exterior decoration. By reducing its density, it can expand its application field, save the resources and meet the needs of the times. A light PDCPD foaming resin was designed by using the strong heat release in the curing process of DCPD, which can simultaneously trigger the foaming of thermal expansion microspheres. When the thermal expansion microspheres are heated, bubbles stabilize in the resin matrix and form microporous structures. This will reduce the density of the material while maintaining the desired mechanical properties. In this paper, the thermal expansion microspheres were characterized, and the influence of the viscosity of the material on the dispersion of microspheres, the influence of the amounts of microspheres and curing temperature on the mechanical properties of PDCPD were studied. Finally, the influence of microsphere diameter and distribution on foaming was studied by formula derivation. This provides a theoretical basis for the preparation of expanded microspheres. Adding thermal expansion microspheres into PDCPD can reduce the density of the material while maintaining its mechanical properties which reduces the cost of materials and saves energy. | Polydicyclopentadiene with low density and high performance was synthesized by using thermal expansion microspheres | 10.1007/s00289-022-04296-x |
2023-05-01 | The simultaneous presence of CO 2 -saturated water with natural oil in the transmission pipeline system, often made from steel, is inevitable. Therefore, in the present study, three brine salinities (low salinity, medium salinity, and high salinity) and six different temperatures (35, 45, 55, 65, 75, 85 °C) in CO 2 -saturated brines containing NaCl, CaCl 2 , MgCl 2, Na 2 SO 4 and KCl were employed to study the individual and synergistic effects of brine salinity and temperature on CO 2 corrosion of low carbon API N80 steel. According to Tafel polarization tests results, in the 35-65 °C temperature range, increasing the brine salinity resulted in a decrease in the corrosion rate; however, from 65 to 85 °C, by increasing the salinity from low to high, the corrosion rate increased. In all brine salinities, increasing the temperature resulted in the corrosion rate enhancement to a maximum value and then a decrease was observed. Electrochemical impedance spectroscopy and Tafel tests results agreed. Weight loss method was also performed to validate the electrochemical technique and the results confirmed the electrochemical data. According to the quantitative analysis (using the analysis of variance experimental design method), the synergistic action of salt concentration and temperature was higher than the individual action of them and among temperature and salt concentration, the most influential parameter was temperature. Furthermore, according to qualitative analysis results, which was used to predict the direction of variations, the synergistic effect of temperature and salt concentration in all 6 temperatures and both medium and high salt concentrations was accelerating. | Investigation of Individual and Synergistic Effects of Salinity and Temperature on CO2 Corrosion Performance of Low Carbon API N80 Steel | 10.1007/s11665-022-07439-3 |
2023-05-01 | The development of Al 2 O 3 -SiO 2 aerogel with high thermal stability and low thermal conductivity at low cost is meaningful for its scale application. In this paper, Al 2 O 3 -SiO 2 aerogel (ASA) from water glass and aluminum chloride were successfully prepared. For comparison, SiO 2 aerogel (SA) was also prepared. The physical properties, morphology, thermal stability, and thermal conductivity of ASA were explored. The specific surface area of ASA with a Al/Si molar ratio of 0.37 (named ASA-0.37) was 613 m 2 /g at room temperature, while that of SA was 606 m 2 /g. The specific surface area retention rate (ratio of the specific surface area after calcined to that at 25 °C) of ASA-0.37 (11.8%) after calcined at 1000 °C was higher than that of SA (1.2%). After calcined at 1200 °C, the ASA-0.37 displayed a lower thermal conductivity of 0.121 W/m·K than that of SA (0.167 W/m·K). It is shown that mullite crystals were produced during heat treatment of ASA, and it restrained the surface diffusion and viscous flow at high temperatures. Thus, high thermal stability was improved. This work provides a low-cost and useful solution to prepare Al 2 O 3 -SiO 2 aerogel with high thermal stability and low thermal conductivity. Graphical Abstract The graphical abstract shows the mechanism of enhancing high-temperature resistance of the Al 2 O 3 -SiO 2 aerogel. Without the doping of aluminum, the SiO 2 aerogel is severely sintered when the temperature rises to 1200 °C. The SEM graph shows that there is almost no residual three-dimensional network structure and the SiO 2 particles agglomerate into large particles. In Al 2 O 3 -SiO 2 aerogel, the doped aluminum reacts with silica and the mullite crystal is formed. The formed mullite can effectively attenuate the sinter of SiO 2 particles, and thus the three-dimensional network structure is retained so that the high-temperature performance of the aerogel is improved. | Synthesis of Al2O3-SiO2 aerogel from water glass with high thermal stability and low thermal conductivity | 10.1007/s10971-023-06085-y |
2023-05-01 | The cationic monomer 2-((dimethylamino)methyl)-4-formyl-6-methoxyphenyl acrylate (DMAMVA) has been synthesized in facile methods. It was evaluated by 1 H, 13 C NMR, and FT IR. Three thermo-pH responsive terpolymers were synthesized based on N -isopropyl acrylamide, DMAMVA, and styrene in various 5, 10 and 15 mol% DMAMVA. The terpolymer with 10 mol% was modified via post-polymerization with ß-alanine. 1 H NMR, FT IR investigated both terpolymers and post-terpolymer. However, the physical peculiarities have been tested by gel permeation chromatography GPC for molecular weights and dispersity, differential scanning calorimetry DSC for the glass temperature, the contact angle was tested via the wettability test. The UV/Vis spectroscopy measured the phase separation temperature of terpolymers solutions by the turbidity test as the variations of temperature against transmittance percent; on the other hand, micro-DSC has also been implemented to record the phase transition temperature. The complementary of this study will be focused on the separation of biological molecules via the post-polymerization of thermo-pH terpolymers. Graphical abstract | Schiff base post-polymerization based on temperature/pH environmentally responsive poly (NIPAAm-co-DMAMVA-co-S): characterization and the trigger of LCST behavioral changes | 10.1007/s00289-022-04327-7 |
2023-05-01 | As a common safety issue, thermal runaway (TR) of lithium-ion batteries (LIBs) may propagate to adjacent batteries and grow into a large-scale fire, in a multi-cell array or pack. A dynamic pressure chamber was developed to investigate the effect of airflow rates on TR propagation among pouch LIBs under the ambient pressures of 95 kPa and 20 kPa. The results indicate that the ununiform heating and asynchronous trigger of TR between two side of battery are occurred when the TR propagated from TR battery with high temperature over 800°C. The TR propagation can be slowed down under low ambient pressure, e.g., propagation time under 20 kPa is 83 s slightly slower than 73 s under 95 kPa with same airflow rate of 60 L/s. As the increase of airflow rate under 20 kPa from 60 L/s to 150 L/s, peak heat release rate and total heat release increase from 6.1 kW to 29 kW, and from 287 kJ to 872 kJ, and TR fire behaviours also are intensified, which can further shorten the TR propagation time from 83 s to 71 s, through heat feedback from TR combustion fire. The release of toxic/flammable or potentially explosive gases, such as 3620 ppm for total hydrocarbons, 0.97% for CO under 20 kPa during TR propagation needs to be paid attentions especially with low airflow rate. Airflow rate under low pressure condition of 20 kPa has a great impact on the TR propagation, and some mitigation measures and protection design about the LIB module used under low pressure environments should be taken. | Lithium-Ion Battery Thermal Runaway Propagation Characteristics Under 20 kPa with Different Airflow Rates | 10.1007/s10694-022-01281-8 |
2023-05-01 | Safe and efficient detection of hazardous n-butanol gas is very great significance to the health of workers and researchers in chemical environments. In this work, we successfully developed a GaN gas sensor by a simple solvothermal method and a low-temperature nitridation process. Material characterization results show that one-dimensional nanorods structures were obtained and the products presented a superior growth orientation along with (101) plane. The gas sensing test results show that the sensor exhibits excellent responsivity, repeatability, and selectivity to n-butanol at room temperature. The response and recovery time of the sensor to 200 ppm n-butanol gas was 45 s/34 s. Gas adsorption model and electron depletion layer theory were established to understand the n-butanol sensing mechanism. This work provides the possibility for its real application in n-butanol detection with safe and efficient at room temperature. Graphical Abstract | GaN Nanorods Gas Sensor for Highly Sensitive n-butanol Detection at room Temperature | 10.1007/s13391-022-00400-5 |
2023-05-01 | Climate models are vital to the assessment of the impacts of climate change in the Central African regions. Establishing how well models reproduce key processes is important to the confidence we attach to these tools. This study examines model representation of the September to November characteristics, such as location and intensity, of the African Easterly Jet (AEJ) north and south in a sample of 16 commonly evaluated CMIP5 and CMIP6 models and in two reanalyses (ERA5 and MERRA2). The analysis evolves to assess key drivers of the AEJ from energetic interactions, the characteristics of mid-level highs and thermal lows and the nature of surface thermal heating. Over West Africa, several models miss the southeast-northwest orientation of the AEJ-N core, leading to a gap of around 6 0 in the location of the jet while most CMIP5 models also fail to locate AEJ-S over southern Central Africa. In general, the spread of simulated AEJ locations around reanalyses is larger for the CMIP5 sample compared to CMIP6 equivalent models, indicating improvement from CMIP5 to CMIP6 in this 16 model subset. However, this improvement in some CMIP6 models (e.g. GISS-E2-1-G and MIROC6) is not related to a maximum surface meridional gradient in temperature. Most CMIP5 and CMIP6 models underestimate the surface temperature gradient over AEJ-N region. As a first order diagnostic of the jet's acceleration, most coupled models better simulate the atmospheric energetic interactions over AEJ-N region that leads to its strong contribution to AEJ-N maintenance compared to AEJ-S. This study strengthens our understanding of the mid-level circulation over Central Africa by detecting gaps in the mechanisms maintaining the AEJ in coupled models and highlights processes that should be improved in future ensembles. | How do coupled models represent the African Easterly Jets and their associated dynamics over Central Africa during the September–November rainy season? | 10.1007/s00382-022-06467-y |
2023-05-01 | In this study, the temperature of the low-temperature reduction-diffusion (LTRD) process was successfully decreased to below 600 °C by introducing LiCl-KCl eutectic molten salt with a low eutectic point (352 °C) as a solvent for Ca reductant. Therefore, the Sm-Fe binary compounds, which were synthesizable at previously-unexplored low temperatures by the LTRD process using LiCl-KCl eutectic molten salt, were investigated, including whether a new metastable or ThMn 12 -type Sm-Fe binary phase was formed. The Sm-Fe phase transitions of the Sm-Fe binary compounds at a low temperature were identified, and it was found that MgCu 2 -type Sm-Fe, PuNi 3 -type Sm-Fe and TbCu 7 -type Sm-Fe phases were synthesized and stable at 400, 500 and 550 °C respectively. Although no new metastable Sm-Fe and ThMn 12 -type Sm-Fe compounds were discovered in this study, this work can demonstrate that it is possible to synthesize the Sm-Fe phase at very low temperatures by the LTRD process for the first time. Graphical Abstract | Low-temperature synthesis of Sm-Fe binary compounds by reduction-diffusion process using an eutectic salt solvent | 10.1007/s12598-022-02219-3 |
2023-05-01 | Abstract Herein is presented a preliminary concept of a nuclear power installation (NPI) based on a low-power multipurpose test research reactor with a supercritical pressure light water coolant (LMTRR-SCP), which can operate as a test or research reactor, and has the following capabilities: substantiation of operating conditions for a supercritical water-cooled power reactor in the fast neutron spectrum; adjustment of the design operating regimes of the reactor with supercritical coolant conditions (including reactor startup, attainment of the energy power level, switch-over between power levels, rated power operation, shutdown, etc.); reactor irradiation of promising types of nuclear fuel, absorbing and structural materials for nuclear installations with fast, intermediate, or thermal neutron spectrum; comprehensive experimental and numerical investigations to obtain information required for development and verification of numerical codes; evaluation of new types of equipment for various process systems (including elements of emergency cooling systems, steam generators, etc.), instruments, and control, monitoring, and diagnostics systems for power reactors of various types. Investigations into the closed nuclear fuel cycle (CNFC) problem; utilization of actinides and handling of long-lived fission products, including pilot demonstration closure of the fuel cycle; mastering of processes for the manufacture of radionuclide products for various applications; production of modified materials; and use of the reactor’s thermal energy for heat and power generation. A potential also exists for the development of international cooperation within the scope of joint research programs on the basis of LMTRR-SCP. | The Concept of a Nuclear Power Unit on the Basis of a Low-Power Multipurpose Test Research Reactor with Supercritical Light-Water Coolant | 10.1134/S0040601523050063 |
2023-05-01 | Release of hazardous heavy metals into the environment by industries is one of the major problems affecting human health. Researchers worldwide are working on the preservation of the quality of water and the prevention of environmental contamination. Removal of heavy metals from wastewater by various methods has been widely researched. Heavy metal sequestration/remediation is considered expensive due to the use of non-regenerable metals and the high cost involved when conventional methods are used. Scientists are involved in the adsorption process and various materials, with various materials being used for this purpose. Adsorption is an efficient purification technique due to benefits like stabilization, utility, low cost, installation convenience, and efficiency. Adsorption reduces heavy metal levels to very low concentration through the use of low-cost agro-waste adsorbent materials such as agricultural/non-agricultural biomass, algal/food biomass, activated carbon/biochar, and zeolite/clay minerals. Adsorption of metal on an adsorbent is a complex problem, specifically agro-waste, as it is regulated by different variables. Complexation, chemisorption, surface adsorption, pore complexity, micro-precipitation, and ion-exchange are part of this process. In adsorption, the functional components of biological material such as sulphydryl, amido, hydroxyl, and carboxyl groups are attached to metal ions and are separated from wastewater. This review discusses how low-cost biosorbents like sawdust, leaves, fruit peels, and crop waste–like husk, shell, hull, fiber, residue, and biofertilizers can be used as adsorbent material for the removal of zinc(II) metal ions from wastewater. | A comprehensive review on zinc(II) sequestration from wastewater using various natural/modified low-cost agro-waste sorbents | 10.1007/s13399-021-01822-1 |
2023-05-01 | In this study, a modified catalytic converter was employed to treat the harmful exhaust gas pollutants of a twin-cylinder, four-stroke spark-ignition engine. This research mainly focuses on the emission reduction of unburnt hydrocarbons, carbon monoxide, and nitrogen oxides at low light-off temperatures. A sucrolite catalyst (sucrolite) was coated over the metallic substrate present inside the catalytic converter, and exhaust gas was allowed to pass through it. A scanning electron microscope, X-ray diffraction, and Fourier transform infrared spectroscopy were used to investigate the changes in morphology, chemical compounds, and functional group elements caused by the reactions. Catalytic reactions were studied by varying the engine loads and bed temperatures, and the results were compared with those of the commercial catalytic converter. The results show that sucrose present in the catalyst was suitable at low temperatures while alumina was suitable for a wide range of temperatures. In the case of the modified catalytic converter, the maximum catalytic conversion efficiencies achieved for oxidizing CO and HC were 70.73% and 85.14%, respectively, and for reduction reaction at NO x was 60.22% which is around 42% higher than in commercial catalytic converter. As a result, this study claims that sucrolite catalyst is effective for low-temperature exhaust gas. Graphical abstract | Experimental investigation on sucrose/alumina catalyst coated converter in gasoline engine exhaust gas | 10.1007/s11356-022-20655-7 |
2023-05-01 | Time–temperature–transformation (TTT) diagram plays a critical role in designing appropriate heat treatment process of steels by describing the relationship among holding time, temperature, and quantities of phase transformation. Making predictions for TTT diagrams of new steel rapidly and accurately is therefore of much practical importance, especially for costly and time-consuming experimental determination. Here, TTT diagrams for carbon and low-alloy steels were predicted using machine learning methods. Five commonly used machine learning (ML) algorithms, backpropagation artificial neural network (BP network), LibSVM, k-nearest neighbor, Bagging, and Random tree, were adopted to select appropriate models for the prediction. The results illustrate that Bagging is the optimal model for the prediction of pearlite transformation and bainite transformation, and BP network is the optimal model for martensite transformation. Finally, the ML framework composed of Bagging and BP network models was applied to predict the entire TTT diagram. Additionally, the ML models show superior performance on the prediction of testing samples than the commercial software JMatPro. | Machine learning study on time–temperature–transformation diagram of carbon and low-alloy steel | 10.1007/s42243-023-00932-6 |
2023-05-01 | A low-permittivity Li 5 Al 5 Zn 8 Ge 9 O 36 microwave dielectric ceramic was prepared via a conventional solid-phase reaction, and its sintering behavior, phase structure, and microwave dielectric properties were investigated. The Li 5 Al 5 Zn 8 Ge 9 O 36 ceramic had a cubic spinel structure, and no other phases were detected. The microstructure of the ceramic was relatively uniform and dense. The Li 5 Al 5 Zn 8 Ge 9 O 36 ceramic sintered at 1150°C exhibited excellent microwave dielectric properties ( ε r = 6.66, Q × f = 24,600 GHz, and τ f = −38 ppm/°C), indicating that it is a good candidate for microwave equipment. | Sintering Behavior, Phase Structure, and Microwave Dielectric Properties of Low-Permittivity Li5Al5Zn8Ge9O36 Ceramics | 10.1007/s11664-023-10295-z |
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