Soft Magnetic Nanocrystalline Alloys: Materials and Models

By: Victorino Franco, Material Matters, 2016, 11.4

Victorino Franco
Departamento de Física de la Materia Condensada, ICMSE-CSIC
Universidad de Sevilla, P.O. Box 1065, 41080, Sevilla, Spain

Magnetic materials permeate numerous daily activities in our lives.1 They are essential components of a diversity of products including hard drives that reliably store information on our computers, decorative magnets that keep the shopping list attached to the refrigerator door, electric bicycles that speed our commute to work, as well as wind turbines for conversion of wind energy to electrical power. While permanent magnets require materials that maintain their magnetization even under the influence of external stimuli, soft magnetic materials can easily change their magnetization when external conditions require it. Permanent magnets require the magnetization vs. field hysteresis loop, M(H), to be broad, with a large coercive field in order to allow energy to be stored in the material. In contrast, soft magnetic materials require a narrow hysteresis loop, which implies the use of small amounts of energy to magnetize the material. As the area of the loop is related to energy losses during the cyclic magnetization of the material, a low coercive field implies better energy efficiency of the final application in which the soft magnetic material is used.

In addition to saturation magnetization (Ms), the most relevant properties of soft magnetic materials are the coercive field (Hc) and the magnetic permeability (μr). Maximizing Ms and μr uses less material to achieve the same value of magnetic moment (Ms) and a larger response to the excitation field (μr). In contrast, optimized soft magnetic materials have the lowest possible value of Hc. From a practical point of view, large values of μr imply that permeability and susceptibility (χ) are interchangeable for the purpose of describing the properties of the material, expressed as μr = 1 + χ ≈ χ. In addition, large susceptibility requires additional attention when characterizing the magnetic material. The magnetic field sensed by the sample, the internal field Hi, is not directly the applied field Ha, but rather depends on the demagnetizing factor (N) of the sample: Hi = Ha – NM. If we disregard the difference between internal and applied fields and we consider that the apparent susceptibility of the sample (χa) associates magnetization and applied field (instead of relating magnetization and internal field, which stands for the intrinsic susceptibility of the material, χ) we obtain:

Therefore, for samples with large values of N made of materials with a large value of χ, the apparent susceptibility does not depend on the actual value of the susceptibility of the material, but only on the demagnetizing factor, as: χa ≈ 1/N (Equation 2).

Thus, the measurement is exclusively dependent on the shape of the sample. To avoid this artifact, geometries that minimize N, such as long wires magnetized along their axis, planar samples magnetized in plane, or toroids magnetized along the toroidal direction are best used. As a direct consequence of Equation 2, the internal field is cancelled, shielding the magnetic field from a spatial region. In fact, a cage made using a soft magnetic material with large susceptibility provides a path for the magnetic field, minimizing its value in the interior of the cage. This explains why mu-metal®, with relative permeability values on the order of 500,000, is used in this type of application.

Scientific publications on soft magnets have steadily increased over the past decades. For example, the discovery of the alloy FINEMET® with its outstanding soft magnetic properties has made the field more attractive to researchers.2 A comparison between the number of papers published on soft magnets to those on hard, or permanent magnets (Figure 1), shows the latter field has been more active in recent years. The accelerating research on soft magnetic nanocrystalline materials in Asia is considered a major driver of growth in the field. This heightened interest has generated an increased demand for and consumption of electrical steel since 2008, promoting the installation of new transformers to improve grid reliability and reduce energy losses. The connection between energy efficiency and soft magnets will help to move soft magnetic nanocrystalline alloy research back into the forefront in the future.

This article provides a brief overview of soft magnetic nanocrystalline alloys. As indicated above, a main goal of optimizing these materials is to obtain the lowest possible coercivity. Here, we review the most important families of nanocrystalline soft magnets with a description of their typical properties and how their composition and processing allow the optimization of these properties. Finally, we present an outlook of potential future fields of interest.

Evolution of the number of publications appearing in Science Citation Index Expanded on soft magnetic materials

Figure 1. Evolution of the number of publications appearing in Science Citation Index Expanded on soft magnetic materials and permanent magnets since 1980. The search string used for the search is provided in the labels.

Desired Properties

The dependence of coercivity on crystal size exhibits two different behavioral regimes. The traditional method of decreasing coercivity in soft magnetic materials has historically been to increase grain size because this decreases the amount of grain boundaries that act as pinning centers for the domain walls. By increasing grain size from 100 nm to 100 μm, it is possible to decrease Hc from ~10,000 A/m to values on the order of 1 A/m. The counter-example of this approach appeared with the emergence of amorphous and nanocrystalline materials. By decreasing grain size to values on the order of 10 nm or even making the solid amorphous, coercivity decreases to reach values comparable to those of very large crystals. Taking into account that an amorphous structure is, by definition, full of defects, the previous argument of decreasing coercivity with decreasing concentration of defects no longer holds true. This characteristic behavior can be explained with the Random Anisotropy Model (RAM) of Alben, Becker, and Chi3 and has been applied to nanocrystalline alloys by Herzer.4

Random Anisotropy Model: An Explanation Based on Analogies

A formal explanation of the RAM remains elusive for researchers more interested in material properties than in the development of physical models. However, understanding the physics behind the model can help in designing materials with the desired performance. We use several analogies taken from everyday life to grasp the concept of RAM. The message here is that the existence of very different length scales in the sample is responsible for the vanishing effective anisotropy of the amorphous and nanocrystalline alloys, which gives rise to extremely low coercivity values.

The first example takes us on a walk to a traditional monument found in many old cities, like Sevilla. Many of these ancient cities have patios with a floor made of numerous pebbles. When walking on top of these floors, those wearing high heels will typically have more difficulty walking than those wearing flat-soled shoes. The most reasonable explanation for this circumstance is that high heels have a typical size comparable to the pebbles and the gaps between them so they detect the discrete maximum and minimum heights of the floor. Flat shoes average the irregularities and allow us to walk more steadily because the heel is much longer than the pebbles and gaps.

Another example uses two refrigerator magnets with the same characteristics (ideally, two identical ones). Magnets of this type are fabricated using polymer-bonded ferromagnetic particles with a domain structure consisting of a set of stripes pointing outward and inward on one side, with the other side containing closure domains. The side with the closure domains is typically decorated and will not stick to the fridge. When one magnet is placed directly on top of the other with the same orientation (decorated sides facing the exterior), the magnets stick together. However when one magnet is slid perpendicular to the stripe domain, the upper magnet jumps as it moves along the attractive and repulsive regions with a periodicity corresponding to twice the domain width. As both the upper and lower magnets have the same characteristic length, i.e., the width of the domains, the system samples energy maxima and minima and they are detected macroscopically. This can be felt in our hands when trying to move the magnets, often producing a sound due to the abrupt attaching and detaching of the flexible laminae. However, if we rotate the upper magnet 90° with respect to the lower magnet, in a perpendicular orientation of the stripe domains of both laminae, the movement in any direction becomes smooth. It is not because the local maxima and minima have disappeared. There are still regions where equal poles face each other and therefore repel, as well as areas in which opposite poles lie on top of each other, creating attraction. The difference with respect to the previous situation is that any position of the upper magnet samples the same amount of attractive and repelling areas. The periodicity of the lower magnet remains the width of the domains, while the periodicity of the upper magnet turns to the length of the magnet. As one is much larger than the other, we cannot macroscopically detect the local energy difference and the magnets displace smoothly, similar to the flat-soled shoes on the pebbled patio.

A Simple Model for Nanocrystalline Alloys

Nanocrystalline alloys also can be modeled in a simple fashion as an ensemble of single domain nanoparticles (shown as squares in Figure 2A) with a typical grain size of 10 nm and with randomly oriented easy axes. Even if Fe-based nanocrystals have cubic magnetocrystalline anisotropy, we consider uniaxial anisotropy in the current model. We will show that the effective anisotropy is almost averaged to zero, thus this assumption of symmetry does not affect our conclusion. Consider the case in which the domain size (connected to the magnetic correlation length and marked as a thick white square in Figure 2B) is comparable to the structural correlation length (the grain size in Figure 2A). Assuming we have a domain in which the magnetization is oriented in the horizontal direction inside the white square, we color code the anisotropy energy of the different crystals from blue (minimal anisotropy energy) to red (maximal anisotropy energy). It is easy to see in the figure that it is not equivalent to displace this domain in all directions, since in some cases we gain blue squares (when moving to the right), while we don’t notice a remarkable difference in red or blue when moving up because there is anisotropy in the displacement of the domain. When we progressively decrease grain size while keeping the domain size constant, differences in energy will become gradually smaller when we move the domain in any direction, becoming negligible below a certain grain size. Each grain has its own anisotropy energy, but the system as a whole does not present anisotropy. In order to perform this simulation more quantitatively, we create different grids using different ratios of grain size to domain size and place the correlated domain at all positions in the grid, calculating the total value of energy in each position and the difference between maximal and minimal energy values for each of the grids. When we plot the difference in energy as a function of the number of particles inside each domain, N, we clearly observe a decreasing trend that can be fit to a 1 / law. Taking into account, for this model, anisotropy is a function of the difference in energy for each position of the domain inside the  grid, we observe that the effective anisotropy, K*, corresponds to K* = K / ,where K is the anisotropy of the crystals. This is the same result formally obtained from the RAM and originates from the difference between the magnetic correlation length and the structural correlation length. As a consequence of this discussion, when particle size decreases noticeably below the exchange correlation length, the effective anisotropy decreases toward zero and makes coercivity practically null.

This simplistic explanation, while keeping the essence of the phenomenology, was improved by also considering nanocrystalline alloys are not only formed by the nanocrystals, but they are two-phase systems in which the nanocrystals are embedded in a residual amorphous matrix, which is also ferromagnetic. More sophisticated models for multiphase materials have been developed5,6 that also include the contributions of magnetoelastic energy.

Set of Lc-sized particles with randomly oriented uniaxial anisotropy

Figure 2. A) Set of Lc-sized particles with randomly oriented uniaxial anisotropy. B) Color-coded energy of such crystals if their magnetization is horizontal, showing one particular size of the magnetic correlation length Lm. C) Relative differences in energy of the correlated region when placed in all different areas of the ensemble, as a function of the number of crystals inside the correlated region (by altering the Lm/Lc ratio); inset: logarithmic plot and linear fit to the data, showing 1 / dependence.

Soft Magnetic Nanocrystalline Alloys

As indicated in the previous section, obtaining materials in which the exchange correlation length is much larger than the structural correlation length will lead to effective magnetic anisotropies that are negligible when compared to the magnetocrystalline anisotropy of the bulk material. In practice, this can be achieved by controlled crystallization of a precursor amorphous alloy.

A major breakthrough in this research field took place with the discovery of the FINEMET® alloy by Yoshizawa, Oguma and Yamaguchi in 1988.2 This alloy is formed from Fe, Si, and B, with small additions of Cu and Nb, and has a typical alloy composition of Fe73.5Si13.5B9Cu1Nb3. The alloy is usually fabricated using rapid solidification techniques such as melt spinning in order to obtain an amorphous precursor with the desired composition. At this stage of the fabrication process, the role of B is to increase the glassforming ability of the precursor alloy. Subsequently, the obtained ribbons are submitted to controlled annealing, typically 1 h at temperatures on the order of 500 °C in order to obtain the desired microstructure of α-FeSi nanocrystals with a typical grain size of 10 nm embedded in a residual ferromagnetic amorphous matrix. The role of Cu is to favor the nucleation of the nanocrystals via segregation either prior to or at the early stages of nanocrystallization. Conversely, the slow diffusing Nb accumulates at the boundaries of the emerging nanocrystals and hinders grain growth.

This special microstructure creates the optimal soft magnetic properties found in this type of alloy; the nanocrystals couple magnetically through the amorphous ferromagnetic matrix in which they are embedded, making the magnetic correlation length much larger than the size of the nanocrystals and averaging the magnetocrystalline anisotropy down to zero. Nevertheless, magnetocrystalline anisotropy is not the only source of coercivity. Magnetoelastic anisotropy also plays an important role. However, the different sign of the saturation magnetostriction constant of the two ferromagnetic phases (negative for the nanocrystals, positive for the amorphous matrix) means that, for a proper amount of the crystalline fraction, this source of anisotropy also vanishes. This makes FINEMET one of the softest materials known to date, with coercivities under 1 A/m. Compositional variations of the alloy produce slightly different Si content in the nanocrystals, altering the value of their magnetostriction constant. This modifies the overall magnetic anisotropy and alters either the optimal crystalline fraction to minimize coercivity, or prevents the overall magnetostriction from vanishing.7

The dependence of coercivity on annealing temperature, i.e., changing microstructure, is illustrated in Figure 3.8 As cast, the amorphous alloy is considered soft for most applications. Annealing at temperatures below the first crystallization stage produces a decrease of coercivity due to stress relaxation processes, diminishing magnetoelastic anisotropy. The appearance of the first nanocrystals increases coercivity by acting as pinning centers for the domain walls and by inducing new stresses in the sample. Increasing annealing temperature further increases the crystalline volume fraction. When the fraction is large enough, the nanocrystals are magnetically coupled through the ferromagnetic amorphous matrix, averaging the magnetocrystalline anisotropy according to the random anisotropy model extended to two-phase systems.5,6 Finally, the onset of the second crystallization stage, with the precipitation of highly anisotropic iron boride type phases, increases coercivity to such an extent the material is of no use as a soft magnet.

Annealing temperature dependence of room temperature coercivity

Figure 3. Annealing temperature dependence of room temperature coercivity and initial susceptibility of Fe76Cu1Nb3Si10.5B9.5 alloy.

Fabrication and Processing

The most common methods for obtaining nanocrystalline microstructure include either conventional annealing in a furnace or Joule-heating/flash annealing, i.e., passing a current through a sample in order to heat it in a controlled fashion. The latter method has been proven useful in reducing the brittleness of the nanocrystalline samples9 and is also combined with the simultaneous application of mechanical stress.10 Processing the alloy under the combined effect of temperature and magnetic field is also useful for inducing anisotropy in the alloys and, therefore, controlling the shape of the hysteresis loop, making them more appropriate for certain applications.11–13

Although there have been attempts to produce these ultra-soft nanocrystalline alloys using mechanical alloying of pure elemental powders, the coercivity of these powders is considerably higher than that obtained for ribbon-shaped samples.14 The increase in magnetoelastic anisotropy due to the additional microstrains and the reduced mobility of domain walls as a result of the size of the powder particles are the main causes of the increased coercivity. It is also important to consider the difficulties in incorporating B into the alloy, despite starting from amorphous or crystalline B powders.15

Compositional Effects

In recent years, there have been numerous studies on the influence of composition on the soft magnetic properties of amorphous and nanocrystalline alloys. Due to the necessary brevity of this paper, the reader is referred to the literature for more comprehensive reviews.16,17 In addition to the FINEMET® alloy and its variations already mentioned in this paper, the three most relevant families of nanocrystalline alloys for soft magnetic applications are NANOPERM®, HITPERM, and NANOMET®. NANOPERM alloys have a typical composition of Fe88Zr7B4Cu.18,19 The larger Fe content and the lesser amount of B increases its saturation magnetization with respect to FINEMET alloys. The nanocrystalline phase consists in α-Fe, in contrast to the FINEMET alloy which also contained Si in the nanocrystals. This has made these alloys a preferred system for the study of the nanocrystallization process via Mossbauer spectroscopy.20

HITPERM alloys were designed as high-temperature soft magnetic materials.21 Their original composition was Fe44Co44Zr7B4Cu, in which Co serves two purposes. On one hand, it helps to maximize the magnetic moment, as Fe-Co alloys are at the top of the Slater-Pauling curve. On the other hand, Co increases the Curie temperature of both the residual amorphous phase and the nanocrystals (which are α-FeCo and α’-FeCo) and allows the operation of HITPERM alloys at much larger temperatures than the other families. But for high temperature applications, the challenge is not only connected to the Curie temperature of the phases, but since we are dealing with metastable materials, we also have to take into account the temperature at which microstructural transformation will take place. This family of alloys fulfills both requirements.

The latest addition to the families of soft magnetic nanocrystalline alloys is the NANOMET alloy, with typical composition Fe83.3–84.3Si4B8P3–4Cu0.7.22 NANOMET was developed to increase the saturation magnetization and minimize material cost by reducing or eliminating the metallic additions of Nb, Zr, Mo, and Cu which were usually required in the alloy families in order to achieve the nanocrystalline microstructure. These nanocrystalline alloys show high saturation magnetization, comparable to the commercial Fe-Si crystalline soft magnetic alloys, and low coercivity.

Regardless of the alloy family, nanocrystalline soft magnets must be optimized for specific operating conditions. A material with good performance at room temperature will most likely not be suitable for cryogenic applications. Cryogenic application studies of the compositional effects in the (Fe,Si,Al)NbBCu alloy series show that proper selection of the Fe:Si:Al ratio allows for the optimal combination of high saturation magnetization, low coercivity, and large electrical resistivity at liquid nitrogen temperatures.23 In another recent example, the Curie temperature of amorphous and nanocrystalline alloys was tuned by compositional variation of the Co:Ni ratio in the Fe882xCoxNixZr7B4Cu1 alloy series with the aim of analyzing the potential of Fe-based amorphous alloys for room temperature magnetic refrigeration.24 The Fe88–2xCoxNixZr7B4Cu1 alloy series exhibits the largest refrigerant capacity (RC) of Fe-based amorphous alloys found to date, while still keeping one of the largest magnetic entropy changes among Fe-based amorphous alloys. For magnetic refrigeration, it appears that nanocrystalline Fe-based25 and Ni-based26 alloys are not suitable and amorphous alloys are preferred, since the magnetic entropy change peak of the two-phase nanocrystalline alloys is split between the magnetic phase transition of the amorphous phase and that of the nanocrystals, decreasing its total magnitude.27

In addition to their use as soft magnets, ultra-soft magnetic materials can be combined with other materials for the development of exchangecoupled nanocomposite permanent magnets, in which a nanoscale soft magnetic phase is added into a hard magnetic phase matrix, increasing the energy density of the composite due to interphase exchange coupling.28

Nevertheless, the scientific interest in soft magnetic nanocrystalline alloys is not only driven by their technological applications and potential to increase energy efficiency. Their two-phase nature, with magnetic phases with different Curie temperatures, makes them a good testing ground for conducting fundamental studies in magnetism. Soft magnetic nanocrystalline alloys have been used to study the superparamagnetism of nanocrystals embedded in the matrix29 in order to develop models of the dipolar interactions between superparamagnetic nanoparticles30–33 or to propose procedures for the determination of critical exponents of multiphase magnetic systems.26

Conclusions and Outlook

Nanocrystalline alloys are among the softest magnetic materials known to science, and different alloy families have been optimized for unique applications and operating conditions. In addition to compositional effects that will affect intrinsic magnetic properties, the use of different processing methods enables the optimization of extrinsic properties such as coercivity.

The physical reason for the extremely low values of magnetic anisotropy and coercive field can be explained using the random anisotropy model: the two characteristic length scales of nanocrystalline alloys (grain size and magnetic correlation length) are very different, and anisotropy cannot be detected macroscopically, even if each nanocrystal is anisotropic.

Soft magnets are currently used in a variety of applications, ranging from energy conversion to sensors. Remaining challenges in the development of soft magnetic nanocrystalline alloys include the optimization of material properties for specific applications and the enhancement of their usability by decreasing brittleness and increasing thermal stability of the metastable phases. These goals can be achieved by a combination of compositional changes and appropriate processing of the alloys. Tuning the hysteresis loops by processing the materials under the simultaneous influence of magnetic field, stress, and temperature is a promising route to broadening the applications of nanocrystalline soft magnets. In addition, the design of exchange-coupled hard-soft magnetic nanocomposites is an area of significant interest in which ultrasoft nanocrystalline alloys may play a role. Moreover, the interest in soft nanocrystalline alloys is not limited to technological applications as these materials are also a good testing ground for developing fundamental models of multiphase magnetic materials.

This work was supported by MINECO and EU FEDER (project MAT2016-77265-R) and the PAI of the Regional Government of Andalucia.

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Linear Equations and Functions

Constant Proportionality A constant ratio of two variables related proportionally
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Linear Equations An equation whose solutions form a straight line on a coordinate plane
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Slop-Intercept A linear equation written in the form y=mx+b, where m represents slope and b represents the y- intercept
Rate of Change The ratio of the change in the output value and change in the input value of a function
Slope A measure of the steepness of a line on a graph; the rise divided by the run
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Firefox Lorentz

Mozilla Foundation

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Overshot WaterWheel....
The overshot wheel is the most common wheel in north America. It is a gravity wheel. This means that it harnesses the force of gravity acting vertically on the water as it travels from the top to the bottom of the wheel. Properly designed for a particular site, and correctly timed, an overshot wheel can slow the natural velocity of the falling water to as little as 10% of what it would be if the wheel was not there.
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When the head, or fall of water was not sufficient for a large diameter overshot wheel, the breast wheel often is used. This is halfway between the overshot and undershot wheels. Water strikes the buckets of the breast wheel about midway between top and bottom, using the weight of the water for a 90 degree segment of arc. While more efficient than the undershot, their efficiency is far less than the overshot, which uses the weight of the water for a full 180 degrees.

Undershot Waterwheel
This type of waterwheel relies on the flow of water, coming along the base flowing at a good rate of speed to push or thrust the waterwheel. This type of waterwheel is used on mills built on rivers or streams that do not have any height or (head). Undershot wheels are normally narrow and have to have the channel walls very close to the sides of the wheel to maximize the flow of water to pass through the wheels to generate power. This type of wheel is generally the least efficient type of wheel - usually in the 30-50% range. The exception to this is the Poncelet wheel that can get up to 80% efficiency if the channel is properly constructed and the buckets are designed right.

Original artwork by Daniel M. Short, CC BY-SA 2.5


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Addictive Potential

The addictive potential of a drug varies from substance to substance, and from individual to individual. Dose, frequency, pharmacokinetics of a particular substance, route of administration, and time are critical factors for developing a drug addiction.

An article in The Lancet compared the harm and addiction of 20 drugs, using a scale from 0 to 3 for physical addiction, psychological addiction, and pleasure to create a mean score for addiction. Selected results can be seen in the chart below.Wikipedia narcotic chart

Capture RatesWikipedia narcotic chart

The percentage of users who reported that they had become addicted to their respective drug at some point.

Substance Abuse

Also known as drug abuse, is a patterned use of a substance (drug) in which the user consumes the substance in amounts or with methods which are harmful to themselves or others. The exact cause of substance abuse is impossible to know because there is not just one direct cause. However substance abuse and addiction is known to run in families. One theory suggests there is a genetic disposition which predisposes certain individuals toward substance abuse. Another suggests substance abuse is learned there for people subjected to substance abuse by those around them begin to copy the same behaviors. Substance abuse might start out as a bad habit but when and if addiction develops it manifests as a chronic debilitating disease.

Drug Abuse PictureThe terms have a huge range of definitions related to taking a psychoactive drug or performance enhancing drug for a non-therapeutic or non-medical effect. All of these definitions imply a negative judgment of the drug use in question (compare with the term responsible drug use for alternative views). Some of the drugs most often associated with this term include alcohol, substituted amphetamines, barbiturates, benzodiazepines (particularly alprazolam, temazepam, diazepam and clonazepam), cocaine, methaqualone, and opioids.

Use of these drugs may lead to criminal penalty in addition to possible physical, social, and psychological harm, both strongly depending on local jurisdiction. There are many cases in which criminal or anti-social behavior occur when the person is under the influence of a drug. Long term personality changes in individuals may occur as well. Other definitions of drug abuse fall into four main categories: public health definitions, mass communication and vernacular usage, medical definitions, and political and criminal justice definitions. Substance abuse is prevalent with an estimated 120 million users of hard drugs such as cocaine, heroin, and other synthetic drugs.

Substance abuse is a form of substance-related disorder.

Drug Misuse

Legal drugs are not necessarily safer. A study in 2010 asked drug-harm experts to rank various illegal and legal drugs. Alcohol was found to be the most dangerous by far.

Drug AbuseDrug misuse is a term used commonly when prescription medication with sedative, anxiolytic, analgesic, or stimulant properties are used for mood alteration or intoxication ignoring the fact that overdose of such medicines have serious adverse effects. Prescription misuse has been defined differently and rather inconsistently based on status of drug prescription, the uses without a prescription, intentional use to achieve intoxicating effects, route of administration, co-ingestion with alcohol, and the presence or absence of dependence symptoms. Chronic use leads to a change in the central nervous system which means the patient has developed tolerance to the medicine that more of the substance is needed in order to produce desired effects.When this happens, any effort to stop or reduce the use of this substance would cause withdrawal symptoms to occur.

The rate of prescription drug abuse is fast overtaking illegal drug abuse in the United States. According to the National Institute of Drug Abuse, 7 million people were taking prescription drugs for nonmedical use in 2010. Among 12th graders, prescription drug misuse is now second only to cannabis. “Nearly 1 in 12 high school seniors reported nonmedical use of Vicodin; 1 in 20 reported abuse of OxyContin.”

Avenues of obtaining prescription drugs for misuse are varied: sharing between family and friends, illegally buying medications at school or work, and often “doctor shopping” to find multiple physicians to prescribe the same medication, without knowledge of other prescribers.

substance abuseIncreasingly, law enforcement is holding physicians responsible for prescribing controlled substances without fully establishing patient controls, such as a patient “drug contract.” Concerned physicians are educating themselves on how to identify medication-seeking behavior in their patients, and are becoming familiar with “red flags” that would alert them to potential prescription drug abuse.

As a Value Judgment

Philip Jenkins points out that there are two issues with the term “drug abuse”. First, what constitutes a “drug” is debatable. For instance, GHB, a naturally occurring substance in the central nervous system is considered a drug, and is illegal in many countries, while nicotine is not officially considered a drug in most countries. Second, the word “abuse” implies a recognized standard of use for any substance. Drinking an occasional glass of wine is considered acceptable in most Western countries, while drinking several bottles is seen as an abuse. Strict temperance advocates, who may or may not be religiously motivated, would see drinking even one glass as an abuse. Some groups even condemn caffeine use in any quantity. Similarly, adopting the view that any (recreational) use of marijuana or substituted amphetamines constitutes drug abuse implies a decision made that the substance is harmful, even in minute quantities.

Signs and Symptoms

Depending on the actual compound, drug abuse including alcohol may lead to health problems, social problems, morbidity, injuries, unprotected sex, violence, deaths, motor vehicle accidents, homicides, suicides, physical dependence or psychological addiction.

There is a high rate of suicide in alcoholics and other drug abusers. The reasons believed to cause the increased risk of suicide include the long-term abuse of alcohol and other drugs causing physiological distortion of brain chemistry as well as the social isolation. Another factor is the acute intoxicating effects of the drugs may make suicide more likely to occur. Suicide is also very common in adolescent alcohol abusers, with 1 in 4 suicides in adolescents being related to alcohol abuse. In the USA approximately 30 percent of suicides are related to alcohol abuse. Alcohol abuse is also associated with increased risks of committing criminal offenses including child abuse, domestic violence, rapes, burglaries and assaults.substance abuse pills

Drug abuse, including alcohol and prescription drugs, can induce symptomatology which resembles mental illness. This can occur both in the intoxicated state and also during the withdrawal state. In some cases these substance induced psychiatric disorders can persist long after detoxification, such as prolonged psychosis or depression after amphetamine or cocaine abuse. A protracted withdrawal syndrome can also occur with symptoms persisting for months after cessation of use. Benzodiazepines are the most notable drug for inducing prolonged withdrawal effects with symptoms sometimes persisting for years after cessation of use. Abuse of hallucinogens can trigger delusional and other psychotic phenomena long after cessation of use and cannabis may trigger panic attacks during intoxication and with use it may cause a state similar to dysthymia. Severe anxiety and depression are commonly induced by sustained alcohol abuse which in most cases abates with prolonged abstinence. Even moderate alcohol sustained use may increase anxiety and depression levels in some individuals. In most cases these drug induced psychiatric disorders fade away with prolonged abstinence.

Drug abuse makes central nervous system (CNS) effects, which produce changes in mood, levels of awareness or perceptions and sensations. Most of these drugs also alter systems other than the CNS. Some of these are often thought of as being abused. Some drugs appear to be more likely to lead to uncontrolled use than others.

Traditionally, new pharmacotherapies are quickly adopted in primary care settings; however, drugs for substance abuse treatment have faced many barriers. Naltrexone, a drug originally marketed under the name “ReVia,” and now marketed in intramuscular formulation as “Vivitrol” or in oral formulation as a generic, is a medication approved for the treatment of alcohol dependence. This drug has reached very few patients. This may be due to a number of factors, including resistance by Addiction Medicine specialists and lack of resources.

The ability to recognize the signs of drug use or the symptoms of drug use in family members by parents and spouses has been affected significantly by the emergence of home drug test technology which helps identify recent use of common street and prescription drugs with near lab quality accuracy.

Treatment for substance abuse is critical for many around the world. Often a formal intervention is necessary to convince the substance abuser to submit to any form of treatment. Behavioral interventions and medications exist that have helped many people reduce, or discontinue, their substance abuse.

From the applied behavior analysis literature, behavioral psychology, and from randomized clinical trials, several evidenced based interventions have emerged: behavioral marital therapy, motivational Interviewing, community reinforcement approach, exposure therapy, contingency management.

In children and adolescents, cognitive behavioral therapy (CBT) and family therapy currently have the most research evidence for the treatment of substance abuse problems. These treatments can be administered in a variety of different formats, each of which has varying levels of research support.

Alcoholics Anonymous is one of the most widely known self-help organizations in which members support each other not to use alcohol.

Social skills are significantly impaired in people suffering from alcoholism due to the neurotoxic effects of alcohol on the brain, especially the prefrontal cortex area of the brain. It has been suggested that social skills training adjunctive to inpatient treatment of alcohol dependence is probably efficacious, including managing the social environment.

Pharmacological therapy – A number of medications have been approved for the treatment of substance abuse. These include replacement therapies such as buprenorphine and methadone as well as antagonist medications like disulfiram and naltrexone in either short acting, or the newer long acting form. Several other medications, often ones originally used in other contexts, have also been shown to be effective including bupropion and modafinil.

Methadone and buprenorphine are sometimes used to treat opiate addiction. These drugs are used as substitutes for other opioids and still cause withdrawal symptoms.

Antipsychotic medications have not been found to be useful.

 Text is available under the Creative Commons Attribution-ShareAlike License; Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.


Malibu Lagoon Project Threatens the Tidewater Goby and Other Wildlife

NOTE: This is a guest blog post from Jennifer Estes, Program Manager for Sea Save Foundation.

The Malibu Lagoon, a pristine wetland at the base of Malibu Creek located just north of Los Angeles, California, is a lush ecosystem home to a variety of species of flora and fauna. However, years of urban sprawl and human interference have shrunk the size of the lagoon and threatened the well-being of the entire environment.

Two years ago the California Coastal Commission conditionally approved the proposal of the California Department of Parks and Recreation to restore the Malibu Lagoon. However, citizen activists have discovered many flaws and gaps in the official plan to restore the lagoon that will cost an estimated $8.5 million dollars. Such flaws include improper handling of wildlife and reliance on assumptions of outdated science, which can harm both the environment and public health. The City of Malibu, which unanimously voted against the project on April 9, 2012, has persistently lobbied the involved agencies for more answers. Now there is less than one week left before ground breaks on June 1.

The lagoon is home to the Tidewater Goby, a Federally listed endangered species. The behavioral pattern of the Goby is such that they retreat into mud burrows for shelter upon sensing any loud noise or other disturbance to their habitat. To make matters worse, nesting season begins in June, so thousands of eggs will be buried deep in the mud when the project begins. When the bulldozers roll on June 1, both the burrowed Fish and their buried eggs will be destroyed. Nowhere in the state parks’ plan is this issue addressed. In addition to the Goby, the planned project imperils at least one other endangered species and several threatened animals.

Please help save the Lagoon and the residents who thrive in this habitat. Encourage the State Parks to explore other less invasive alternatives by signing our petition.

Photo courtesy of Sea Save

Christine Stewart

If the Goby fish and other species will be destroyed by the project, they need to rethink the whole thing- otherwise, there will be a "pretty" lagoon, but devoid of its aquatic life...

Anita Wisch
Anita Wisch5 years ago

Whenever we get involved to fix something we caused, nature is the loser.

Linda Jarsky
Linda Jarsky5 years ago

Isabel A.
Isabel Araujo5 years ago

Petition signed, thank you.

Marie W.
Marie W5 years ago

We have met the enemy and he is us.

Carole H.
Carole H5 years ago

Jen Matheson
Past Member 5 years ago

This is terrible.

Gianna Macias
Gianna Macias5 years ago

Why can't men stopping wasting nature.

Anna Ballinger
Anna Ballinger5 years ago

Thank you for sharing this.

Ruth S.
Ruth C5 years ago

Humans are the ones that are destroying the world!!


Safety concerns over bad weather commuting

Employee refusing to come to work in bad weather
By Tim Mitchell
|Canadian Employment Law Today|Last Updated: 03/04/2015

Question: How should an employer handle an employee who refuses for safety reasons to commute to work whenever the weather is bad, even if the employer does not consider it bad enough to close the office?

Answer: In the absence of a contractual or statutory obligation, an employer is not required to pay an employee who chooses to take a snow day when the office is open and work is available to be performed. The decision to grant or withhold pay in such a situation is a decision within the employer’s discretion.


Knowledge of the mechanism of association and dissociation of macromolecules is important for many biological structures and processes. Among the examples are the binding and dissociation of substrates of enzyme reactions, the recognition of ligands by their receptors or of DNA sequences by the DNA binding domains of regulatory proteins. These processes have in common a transition from one equilibrium state to another which often is a rare event on the time scale of molecular dynamics simulations of a few hundreds of picoseconds. Conventional computational methods for the sampling of barrier-crossing events increase the probability of unlikely configurations. Once such configurations have been sampled their actual occurence can be determined through the known relation between old and new probabilities. A methodologically related avenue to characterize rare events through molecular dynamics simulation is the addition of external forces which reduce the energy barriers. This approach has the advantage that it corresponds closely to micromanipulation through atomic force microscopy or optical tweezers.

The external force techniques can be applied to study many processes, including dissociation of avidin-biotin complex, dissociation of retinal from bacteriorhodopsin, stretching of DNA, etc.The forces can be defined using the MDScope graphics/MD software developed in our group

Avidin-Biotin Complex

We performed molecular dynamics simulations which induce, over periods of 40~ps to 500~ps, the unbinding of biotin from avidin by means of external harmonic forces with force constants close to those of AFM cantilevers. The applied forces are sufficiently large to reduce the overall binding energy enough to yield unbinding within the measurement time. Our study complements the work by Grubmueller et al. on biotin-streptavidin which employed a much larger harmonic force constant. The simulations reveal a variety of unbinding pathways, the role of key residues contributing to adhesion as well as the spatial range over which avidin binds biotin. In contrast to Grubmueller et al., the calculated rupture forces exceed by far those observed. We demonstrated, in the framework of models expressed in terms of one-dimensional Langevin equations with a schematic binding potential, the associated Smoluchowski equations, and the theory of first passage times, that picosecond to nanosecond simulation of ligand unbinding requires such strong forces that the resulting protein-ligand motion proceeds far from the thermally activated regime of millisecond AFM experiments, and that simulated unbinding cannot be readily extrapolated to the experimentally observed rupture.

MD simulations of protein-ligand adhesion for the avidin-biotin complex.

We are applying the steered molecular dynamics method to investigate the action of human synovial protein phospholipase A2 (PLA2) at the lipid water interface. PLA2 binds to a membrane surface in a scooting mode and catalyzes the hydrolysis reaction of the sn-2 ester bond of phospholipids which subsequently results in the destruction of membrane surface. The actual catalysis is believed to be initiated through the suction of a phospholipid from the membrane surface into the hydrophobic channel of PLA2 where the reaction takes place. The mechanism of this suction is little understood and is hypothesized to be caused by destabilization of the polar phospholipid headgroup by the hydrophobic environment of the binding channel of PLA2. We investigate the process of extrusion of the phospholipid for two modes of coupling of PLA2 to the membrane surface, i. e., tightly and loosely bound modes. Our hypothesis is that prior to extruding the phospholipid, PLA2 must form the tightly bound complex, while the loosely bound complex should not lead to catalysis.

Retinal's Binding Pathway in bR

Formation of bacteriorhodopsin (bR) from the apoprotein and retinal has been studied experimentally, but the actual pathway, including the site of retinal entry, is little understood. Molecular dynamics simulations provide a surprisingly clear prediction. A window between bR helices E and F in the trans-membrane part of the protein can be identified as an entry site for retinal (purple van der Waals spheres in this figure). Steered molecular dynamics, performed by applying a series of external forces of 200--1000 pN over a period of 0.2 ns to retinal, allow one to extract retinal from bR once the Schiff base bond to Lys216 (blue van der Waals spheres) is cleaved. Extraction proceeds until the retinal tail forms a hydrogen bond network with side groups lining the entry window. The manipulation induces a distortion with a fitted RMS deviation of coordinates (ignoring retinal, water, and hydrogen atoms) of less than 1.9 Angstroms by the time the entry window--retinal tail hydrogen bond network forms. The forces used are consistent with those expected for fast extraction and do not indicate significant potential barriers. We suggest that the path followed in the simulated extraction of retinal also describes the binding of retinal. The simulation reveals that movement of a water molecule between Lys216 and retinal's aldehyde group can initiate unbinding.

Dr. Sergey Stepaniants

Sergei Izrailev

Barry Isralewitz

Justin Gullingsrud


Duterte taps coast guard vs lawless violence

President Rodrigo Duterte has tapped the Philippine Coast Guard (PCG)x to help implement the state of national emergency he declared in early September.

Memorandum Order (MO) 4, signed by Executive Secretary Salvador Medialdea on September 26, sought to expand the application of MO 3 that aims to deploy government forces on major streets and thoroughfares as well as crowded places.

MO 3 provided guidelines to the military and police in the implementation of measures to suppress and prevent lawless violence.

Under MO 4, the President tapped the PCG to intensify its activities related to the enforcement and maintenance of maritime safety and security to prevent or suppress lawless violence at sea.

The memorandum states that the PCG should inspect all merchant ships and vessels to ensure compliance with safety standards, rules and regulations.

It also directs the PCG to inspect persons, vessels and watercraft within the maritime jurisdiction of the Philippines, and suspected of committing, or conspiring to commit, an offense in the Philippines.

The President tasked the Department of Justice to closely coordinate with the PCG and other law enforcement agencies for the prompt investigation and prosecution of all individuals or groups apprehended.

Please follow our commenting guidelines.

  1. This is a very wise move to help the President in their own way to suppress the proliferation of drugs and other criminal activities.Now evrybody are working.

  2. DU30 is diverting the PCG to do others things and divert the attention of PN,PAF,Marines and Army so that he can bring the communist in his team, bring China and Russia in Philippine soil.

    Its all out, DU30 is giving the Philippines to China and Communist ideology with flying colors. AFP, please do something to stop this criminal.


Official reprint from UpToDate®

Medline ® Abstract for Reference 28

of 'Iliotibial band syndrome'

Noehren B, Davis I, Hamill J
Clin Biomech (Bristol, Avon). 2007;22(9):951. Epub 2007 Aug 28.
BACKGROUND: Iliotibial band syndrome is the leading cause of lateral knee pain in runners. Despite its high prevalence, little is known about the biomechanics that lead to this syndrome. The purpose of this study was to prospectively compare lower extremity kinematics and kinetics between a group of female runners who develop iliotibial band syndrome compared to healthy controls. It was hypothesized that runners who develop iliotibial band syndrome will exhibit greater peak hip adduction, knee internal rotation, rearfoot eversion and no difference in knee flexion at heel strike. Additionally, the iliotibial band syndrome group were expected to have greater hip abduction, knee external rotation, and rearfoot inversion moments.
METHODS: A group of healthy female recreational runners underwent an instrumented gait analysis and were then followed for two years. Eighteen runners developed iliotibial band syndrome. Their initial running mechanics were compared to a group of age and mileage matched controls with no history of knee or hip pain. Comparisons of peak hip, knee, rearfoot angles and moments were made during the stance phase of running. Variables of interest were averaged over the five running trials, and then averaged across groups.
FINDINGS: The iliotibial band syndrome group exhibited significantly greater hip adduction and knee internal rotation. However, rearfoot eversion and knee flexion were similar between groups. There were no differences in moments between groups.
INTERPRETATION: The development of iliotibial band syndrome appears to be related to increased peak hip adduction and knee internal rotation. These combined motions may increase iliotibial band strain causing it to compress against the lateral femoral condyle. These data suggest that treatment interventions should focus on controlling these secondary plane movements through strengthening, stretching and neuromuscular re-education.
Department of Physical Therapy, University of Delaware, 301 Mckinly Laboratory, Newark, DE 19716, USA. bwn51@yahoo.com


Page 1

The World of

Y M R A O R U B SE I L A Teaching Guide for Daniel Kirk’s Library Mouse Books

About the Author: Daniel Kirk was inspired to write the Library Mouse books after spending countless days with his family perusing the stacks of his local library. He lives in Glen Ridge, New Jersey with his wife, three children, and two rabbits. Visit him at

About the Books: Library Mouse Sam is a library mouse. His home is in a little hole in the wall behind the children’s reference books, and he thinks that life is very good indeed. For Sam loves to read. He reads picture books and chapter books, biographies and poetry, and ghost stories and mysteries. Sam reads so much that finally one day he decides to write a book himself! Sam shares his books with other library visitors by placing them on a bookshelf at night. But there comes a time when people want to meet this talented author. Whatever is Sam to do?

Library Mouse: A Friend’s Tale Sam loves to write and draw, and everyone loves the little books he leaves on the shelves of the library for them to find. But Sam is also very shy around people, and no one at the library has ever met him—until Tom. When the library’s Writers and Illustrators Club is given an assignment to work in partners, Tom finds that he is the odd kid out. Then he discovers Sam’s identity and hopes they can work together on a project. But what will happen if everyone discovers Sam is a mouse? Can Tom keep the secret?

Library Mouse: A World to Explore In the library one evening, Sam meets fellow mouse Sarah, a wild-eyed explorer who loves adventure! Sarah would rather scurry to the tops of the tallest library shelves and roam the darkest corners of the building than read about the places she wants to visit. Unlike Sarah, Sam never climbs up high—he’s too afraid! He’d rather research subjects and write about them. When Sam reveals to Sarah the joy and adventure one can have by reading books, she decides to help him in turn. Can Sarah help Sam overcome his fear of heights? Together this duo shows that, with teamwork and determination, anything is possible.

A Conversation with Daniel Kirk Q: What inspired you to write Library Mouse? Writing “Library Mouse” was a long and winding road. The story started as an “ABC in the Library” book until I discovered that there were already several such alphabet books in print. Around that time I met a school librarian who was plagued with a naughty wild mouse, causing endless mousey mischief in her stacks. This gave me the idea of putting a mouse in my story, and Sam’s personality sort of fell into place with the plot. The library is a perfect home for a mouse who loves to read and write! Q: When you are creating a story, what comes first— the words or the pictures? I think developing characters is a good way to start working on a story, so often I’ll make many drawings before I begin writing. This helps me figure out what my characters will look like, and gives me a glimpse into their personalities. But I don’t do actual illustrations for a book until the story is done and the text is written in stone!

Q: Which is more satisfying for you—writing or drawing? When I spend a lot of time writing, it’s always refreshing and fun to get back to drawing pictures. But when I am swamped with trying to meet a deadline for my illustrations, I long to go back to the world of words. There I can describe a character or scene in just a few words or sentences that it might take me weeks to paint. Sometimes it’s hard juggling both of these skills, but there are many ways to tell stories, and I like exploring them all. That’s why it makes sense for me to write AND draw. Q: You serve as the author and illustrator of the Library Mouse books; how is this experience different from your other projects where you provide the illustrations in collaboration with another author’s story?

Here’s a secret—Sam is really me. He fantasizes that he is bold and adventurous, but in reality he’s kind of shy and reclusive, and most of his adventures take place in his imagination, where it’s safe from real danger. I’m pretty much like that, myself.

More than anything else I love being a solo creator, telling my own stories in my own way and illustrating them with appropriate pictures. I think of myself as an artist and writer working in the medium of books. Once in a while, though, I’ll be offered the chance to illustrate someone else’s story. This has the possibility of forcing me to be creative in a different way . . . I find new ways of expressing ideas, or developing characters. Sometimes I reach a whole different audience with books that I illustrate, but did not write. It’s an interesting experience. Someday it would be fun to have another illustrator tackle one of my stories. No matter what my role, it’s all an adventure in creativity and expression!

Q: In what ways do you think young readers benefit from meeting a character like Sam?

Q: How do you use your local library when putting the books together?

Sam is curious, imaginative, good-hearted, and he sticks at things—he’ll keep trying until he gets something right. The fact that he isn’t perfect, that he’s shy and finds certain things about the world scary and daunting, appeals to kids because they understand his weakness and empathize with him. We all have things we’re afraid of, and we all have to keep exposing ourselves to challenges to make ourselves grow.

Research is a big part of any book, whether you’re writing or illustrating. I use my library all the time to help me with research. In the last couple of years I’ve needed information about what mice, elephants, and hawks looks like, what the North Pole is like in the autumn, how a tow truck works, and how birds are handled in an animal shelter. I’ve researched global warming, how the Dewey decimal system operates, and studied how libraries and librarians have been described in children’s books over the last fifty years. The library is an invaluable tool for me. I’ve gone to the library to photograph a globe, to see how light looks falling on the shelves on a sunny morning and on a cloudy day. Librarians help me find things I’m looking for, and can order books for me that I might find useful. I’d be lost without my local library!

Q: Sam’s character is smart, sensitive, curious, and kind, yet he could also be described as timid because of his anxiety of new places and experiences. What made you decide to develop his personality in this manner?

Library Mouse

Discussion Questions for Library Mouse  As Sam explores the library and reads widely, he begins to create his own stories. Why does reading so many different types of books make this easier for him?  Based on hints embedded in Kirk’s illustrations, how does Sam feel about seeing his books being read by the children that visit the library?  Though he is excited that his books are well loved, Sam is nervous and afraid of people finding out who and what he is. Do you agree with the way he feels?  Consider his dilemma to being asked to attend “Meet the Author Day.” Do you think creating the “Meet the Author” box (with the mirror contained inside) is the best solution to his problem? Why or why not?

EXTENSION ACTIVITIES: Learning the Library Layout: Host a Scavenger Hunt Throughout the course of Sam’s adventures, he explores the library and learns about the different sections of the children’s department. To help students become more familiar with the library, create a scavenger hunt and have students work in small teams to search for answers to the questions you provide. Make sure to:  Decide what areas of the library students need to best become familiar with ahead of time.  Ask simple questions that offer student’s specific direction for their search. An example might be to “find a biography of an American president and determine what year he was born.”  Keep the scavenger hunt fairly short (7–10 questions).  Encourage students to work in small groups and provide prizes for completed sheets.  Prevent crowding by rearranging the order of the questions so that groups are searching for different answers at the same time.

What’s in a Name: Discovering Biographies and Autobiographies As Sam explores the library, he reads a variety of biographies and autobiographies that help him better understand these genres as he begins to create his first book, Squeak! A Mouse’s Life. Using the resources in the library, have students learn more about what makes these types of nonfiction works unique. Have students create a Venn diagram charting the similarities and differences of these types of writing. After discussing these similarities and differences, have students create original biographies. Begin by pairing students up and providing them an interview sheet so they can ask questions of their partner. After gathering necessary information, have them create a biography about their classmate. Alternatively, students can use Sam’s model and write an original autobiography about themselves, creating original art and illustrations or using copies of family photos. Using the title of Sam’s work as a model (Squeak! A Mouse’s Life), have students reflect on what their story would be named or entitled.

Host a “Meet the Author” Day After sharing Library Mouse with classes, have students regroup at stations where tissue box/mirror units have been placed. After allowing students time to “reflect” and consider what story they have to tell as an author, provide them with small, prepared mini-books similar to those created by Sam. Encourage students to write the kind of story they like to read or share a past personal experience. After the story has been drafted, provide the “authors” time to illustrate their work. After all the works have been created, display these books in the classroom and allow time for students to read and share each other’s work. As an enrichment activity, consider hosting a Young Author’s Celebration and invite other classes and families to come celebrate the work of these young authors.

Genre Studies: Generating a Greater Understanding of Literary Categories In Library Mouse, readers discover that Sam reads widely as he explores the vast variety of books within the library. Introduce the term genre to students and have them create a list of the many types of books Sam reads and, eventually, writes. Discuss the major components of these types of books and have students consider what makes these genres unique. Have students analyze the books they have read most recently to determine what genre category in which they fall. Is there a pattern to their reading? After allowing time for analysis and discussion, take students to the library to select a book that falls into a new genre that they haven’t read recently.

Library Mouse: A Friend’s Tale Discussion Questions for Library Mouse: A Friend’s Tale  After the Writing and Illustrators group pairs up to complete their assigned activity, Tom is left without a partner. How do you think this makes him feel? Have you ever been in a similar situation? What was that experience like for you?  Once Tom discovers Sam’s work and his tracks, his curiosity leads him on a quest to learn more about Sam’s identity. Do you think Tom is making the right choice in trying to discover who Sam really is? Have you ever been so curious about something that you searched widely for answers?  Tom fears that if others learn Sam’s real identity, he might be at risk. Do you agree? Why or why not?  Predict what will happen to Sam and Tom after the story ends.

EXTENSION ACTIVITIES: Dynamic Duos: Researching Author/Illustrator Teams Author Daniel Kirk takes special care in his artwork to highlight and acknowledge collaborations of many author/illustrator pairs. After reading Library Mouse: A Friend’s Tale with students, have them closely examine Kirk’s illustrations. What other books are featured in his artwork? Place students in pairs or small groups and have them select a highlighted pair. Take students to the library to learn more about their selected author/illustrator team. Have them answer the following questions:  Who is the author and illustrator?  How many times have they collaborated on books?  What are some of the titles of their work?  Does the pair live close by each other?  Does either partner work with other authors/illustrators?

Perfect Pals: Create a Friendship Handbook

In Library Mouse: A Friend’s Tale readers witness Tom taking special care to win Sam’s trust. Reread the story and answer the following: How does Tom feel when he learns the identity of Sam? What are some of the things Tom does to prove his friendship and protect Sam? In what ways are they ideal friends for each other? After discussing, ask students to consider their own actions and the ways they can prove they are a true friend. Have each student create a Friendship Handbook detailing and listing the qualities and behaviors of good friends.

Library Mouse: A World to Explore Discussion Questions for Library Mouse: A World to Explore

 In Library Mouse: A World to Explore, Sam spends an evening looking at the class projects displayed in the library which highlight what the children have learned about places all over the world. If you could select a place or historical landmark to explore, what would it be? What makes you interested in learning more about this topic?  Sam is very surprised to learn that Sarah also lives in the library. After their initial meeting, they quickly discover that they are both explorers, but the manner in which they conduct their explorations is quite different. What are the benefits to each of their styles? In what ways are Sarah and Sam alike? How are they different? Thinking about yourself, who do you think you are more alike? Why?  Describe Sarah. In what ways is she a good influence on Sam? Do you have a friend who pushes you to try new things? What are some of the benefits of having a friend who is bold and fearless? What are some of the drawbacks?  Looking at the illustrations, which one is your favorite? What is it about the picture that appeals most to you?

Write All About It!: Journaling Activity After discussing the possibility of climbing into the display plane suspended over the library so that they can have a panoramic view of the facility, Sam’s hesitation and fear is obvious. Sarah tells Sam, “Tonight we’re going to get into that airplane, and we’re going to see the world!” After sharing this passage with students, take a few minutes to allow them to study the illustrations. Next, make a list of the emotions that are evident based on the images of the characters. After discussion, share a personal experience where fear temporarily handicapped you. After offering your story (and how you overcame your apprehensions), ask students to reflect on a time where, like Sam, they were afraid to try something new (examples could include starting school, sleeping without a night-light, trying out for a sport, etc.). Have them consider this fearful experience and what made them afraid, and finally, what happened when they chose to try to over come their fear. Allow students a few minutes to reflect before journaling and sharing their story. To enrich this activity, have students draw illustrations of the experience after completing their story.

Introducing the Basics of Research: Guiding Students as They Learn the Research Process Like the student projects referenced in Library Mouse: A World to Explore, students love learning and discovering new topics of interest while exploring the wide variety of informational books in the library. For young children, a basic introduction of research is helpful. Begin by working with your librarian to design and teach basic research lessons. Lessons may include (but are not limited to) an introduction to the Dewey decimal system, the Big6 research model, or I-Search research framework. After selecting the research technique best suited for the students, allow them to self-select a topic of which they want to learn more, and follow these steps outlined in the research model, making sure to offer a wide variety of choices in regard to the creation of a final product.

This guide was created by Rose Brock, a school librarian and doctoral candidate at Texas Woman’s University, specializing in children’s and young adult literature. © 2010 Abrams Books for Young Readers, an imprint of ABRAMS

The World of Library Mouse: A Teaching Guide for Daniel Kirk's Library Mouse Books

A Teaching Guide for Daniel Kirk’s Library Mouse Books


Caribbean reefs underwent significant biotic change during the Late Oligocene and Early Miocene. This was a critical time in the evolution of the modern Caribbean fauna characterized by increasing endemism resulting from regional extinction of lineages that survive in the modern Indo-Pacific. An understanding of the dynamics and potential causes of the Oligocene/Miocene transition, however, is hampered by the relative lack of well-preserved Oligocene to early Miocene coral faunas in the Caribbean. Here we examine new exposures in the Culebra Formation of Panama that contain a well-preserved coral fauna of Early Miocene age. Taxonomic, stratigraphic, and paleoecologic study of the Culebra Formation exposed along the Gaillard Cut of the Panama Canal allows us to infer the paleoenvironments and reef coral communities from the Panama Canal Basin during this critical interval. The Culebra Formation consists of a deepening upward sequence with shallow-lagoon sediments at the base, overlain by fringing reef facies in the middle of the section, and open-shelf to bathyal facies at the top of the section. We recovered 31 species of reef corals from a combination of new and old collections. Comparison of our collections with other Late Oligocene to Middle Miocene reef coral assemblages confirms that there was a major faunal turnover after deposition of the Upper Oligocene Antigua Formation. This turnover consisted of a large number of extinctions followed by an increased rate of first occurrences so that regional diversity did not change appreciably. Improved stratigraphic resolution at this and other Caribbean localities is required to understand fully the dynamics of change during the Oligocene/ Miocene transition.

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The rules of law

The Wikipedia gives its own definition of the Rule of Law according with the following ideas: "The rule of law implies that government authority may only be exercised in accordance with written laws, which were adopted through an established procedure. The principle is intended to be a safeguard against arbitrary rulings in individual cases. Thus, those who make and enforce the law are themselves bound to adhere to it." (Wikipedia, 2006).
This last point is very important in order to understand the significance of the Rule of Law. The lawmakers have to obey the law. That point is the main characteristic of the Rule of Law, because there are some countries in which the government officials behave as if they shouldn't obey the law. In undemocratic societies the people from the government are above the law. That is a very serious situation. That is why they don't have democracy and many times that is why they are underdeveloped countries. Later on we will take a look at some examples in the case of China regarding this topic.
During the last decades a lot of money has been spent trying to apply the Rule of Law in countries with undemocratic societies and in underdeveloped countries. The People's Republic of China is one of those countries. As we can see, the Rule of Law is a very conflictive topic for a lot of people in our present society. We really think that the Rule of Law is very important in order to establish democracy and development in any country. But first let's see what the Rule of Law is. Tom Glass defines the Rule of Law according to the following concepts: "Government decisions are made according to written law and rules; Government sanctions cannot be made up after the fact (ex post facto); Rules are applied as much as possible consistently to all; Courts provide citizens consistent, written process (due process) before life, liberty, or property is taken; Courts provide reasons based upon the law for their decisions." (Glass, 2005).
Chinese people couldn't get the ideas behind these points due to the fact of their Confucian background in which there was a heavy dependence upon the clan or the group. As the UN China puts it: "Under the philosophy that the government represents the people, internal government procedures regulated conflicts between the government and the individual, not laws." (UN China, 2001). There was a rule of man, rather than a rule of law until recently when Chinese leaders have recognize the rule of law as necessary for the establishment of a democratic society.
The Rule of Law is extremely important as a pre-requisite for democracy and development in any country. In a society with a solid Rule of Law we can trust the government officials and everybody feels secure in such an environment where the Law rules. People who opposed the Rule of Law like China's leaders were in favor of the Rule by Law, or in other words, the Rule by Power, or the Rule of Power. For example, general elections are held commonly in China, but only in rural areas, not on a nation-wide level, just on the village level. For example, free expression, association and assembly are constitutional right ...Show more

In the dialogue between China and the West, the Oriental country had been opposed for a long time to the concept of the Rule of Law in favor of the Rule by Law. China's leaders used to considered that the Rule of Law goes against the class struggles in society so they favored a different concept of Rule by Law instead of Rule of Law…
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Nowadays, there is a huge emphasis placed upon training in the workplace. Employers often devote a significant amount of resources to arranging, delivering and recording training provided to their employees. This is of course important. However, despite the emphasis placed on training, how useful in practice is evidence of a company's training regime in defending allegations of fault when there has been a serious accident in the workplace?

It is estimated that up to 80% of accidents at work may be caused by human error ('Reducing error and influencing behaviour' Health & Safety Executive HSG48). Considering this, it is up to employers to attempt to limit the possibility of human error by focusing on their own management and procedures, as opposed to training, so it is less likely accidents will occur.

There is an industry accepted hierarchy of hazard control which is used to minimise or eliminate exposure to hazards. This hierarchy underpins the bulk of current health and safety legislation across a wide spectrum and it sets out the various risk control measures available in the workplace in descending order of effectiveness, as follows:-

  1. Elimination - physical removal of the hazard by redesigning the job or substituting a substance so the hazard is removed or eliminated
  2. Substitution - replacing the material or process with a less hazardous one
  3. Engineering controls - isolating employees from hazards by adapting or installing work equipment, e.g. installing guarding protecting the dangerous parts of machinery or installing ventilation to remove potentially harmful dust or fumes
  4. Administrative Controls - identifying and implementing procedures needed to work safely, e.g. increasing signage, performing risk assessments and undertaking training
  5. Personal Protective Equipment - this measure is deemed the least effective way to control hazards and should be used only where all other measures are considered ineffective.

Therefore, when considering the various risk control measures available in the workplace, eliminating and controlling risks are deemed to be to be most effective with training near the bottom of the list. This means that the employer attending Court and holding up its training records as an indication of compliance may be required to explain why it did not attempt to achieve more effective measures or show that such measures were not reasonably practicable, i.e. possible in the workplace. This may be very difficult to show when, as so often happens the employer has not considered proper compliance at a higher level beforehand.

As an example, many employees require to work at height, however, falls from height are the biggest cause of workplace deaths and injuries. Employers are required to consider the task which requires to be carried out and put the control measures outlined above in place. The employer in these circumstances should firstly consider and act upon whether (1) the need to work at height can be avoided; (2) there is equipment which could be used to prevent a fall, e.g. work platforms or rope access; and (3) the distance and consequences of a fall. Only after these matters are addressed and found impracticable does the question of supply of harnesses and training become relevant in considering fault.

The Enterprise and Regulatory Reform Act, which is expected to come into force later this year, will fundamentally change the civil law relating to damages claims for accidents at work so that employees raising an action will require to establish that their employer was negligent. The employer will in turn have the defence that all reasonable steps were taken to protect their employees. Accordingly, in the future it will be far more difficult for a pursuer to succeed in recovering damages. The statutory regulations and the hierarchy however continue to apply for criminal liability. This may well create the anomalous situation where an employer, successfully prosecuted for a clear breach of statutory regulations is nevertheless able to defend or frustrate a claimant suffering serious injuries because of the same accident.

Currently, training cannot be used as a substitute for proper risk control, e.g. to compensate for poorly designed plant or inadequate work stations. In the future, however, in civil cases proof of adequate training may defeat a civil claim while being largely irrelevant in a criminal prosecution. The implications for employees remain to be seen.