cssi/SciSciGPT-SciSciNet huggingface dataset:
Sangivamycin, a Nucleoside Analogue, Is a Potent Inhibitor of Protein Kinase C

Protein kinase C functions prominently in cell regulation via its pleiotropic role in signal transduction processes. Certain oncogene products resemble elements involved in transmembrane signaling, elevate cellular sn-1,2-diacylglycerol second messenger levels, and activate protein kinase C. Sangivamycin was unique among the nucleoside compounds tested in its ability to potently inhibit protein kinase C activity. Inhibition was competitive with respect to ATP for both protein kinase C and the catalytic fragment of protein kinase C prepared by trypsin digestion. Sangivamycin was a noncompetitive inhibitor with respect to histone and lipid cofactors (phosphatidylserine and diacylglycerol). Sangivamycin inhibited native protein kinase C and the catalytic fragment identically, with apparent Ki values of 11 and 15 microM, respectively. Sangivamycin was an effective an inhibitor of protein kinase C as H-7, an isoquinolinsulfonamide. Sangivamycin did not inhibit [3H]phorbol-12,13-dibutyrate binding to protein kinase C. Sangivamycin did not exert its action through the lipid binding/regulatory domain; inhibition was not affected by the presence of lipid or detergent. Unlike H-7, sangivamycin selectively inhibited protein kinase C compared to cAMP-dependent protein kinase. The discovery that protein kinase C is inhibited by sangivamycin and other antitumor agents suggests that protein kinase C may be a target for rational design of antitumor compounds.
Pulse-based interface circuits for SPR sensing systems [analyte concentration measurement]

This paper presents a means for reducing the impact of dark current, photodetector mismatch (fixed pattern noise), and the background medium on the signals generated by a surface plasmon resonance (SPR) sensing system for determining the concentration of targeted analytes in solution. Results for each circuit component (simulated and experimental) correlate well, with a maximum error of 3%, 7% and 12% in basic behavior (between simulated and actual results) for the dark current reduction, background medium compensation, and weighted sum circuits at relevant operating points, respectively. System level results on SPR signals also demonstrate the usefulness of these circuits for system-on-chip style signal processing. The chip produces a single output that indicates the refractive index (and resulting analyte concentration) of an SPR probe, independent of fluctuations in the background medium.
Strategic planning for disaster recovery with stochastic last mile distribution

This paper considers the single commodity allocation problem (SCAP) for disaster recovery, a fundamental problem faced by all populated areas. SCAPs are complex stochastic optimization problems that combine resource allocation, warehouse routing, and parallel fleet routing. Moreover, these problems must be solved under tight runtime constraints to be practical in real-world disaster situations. This paper formalizes the specification of SCAPs and introduces a novel multi-stage hybrid-optimization algorithm that utilizes the strengths of mixed integer programming, constraint programming, and large neighborhood search. The algorithm was validated on hurricane disaster scenarios generated by Los Alamos National Laboratory using state-of-the-art disaster simulation tools and is deployed to aid federal organizations in the US.
Dynamic response of the piezoelectric polymer PVDF

The paper concerns the dynamic response of polyvinylidene fluoride (PVDF), a commercially available piezoelectric polymer currently used in numerous applications. The paper consists of two parts. The first part presents a summary review of recent experimental results regarding the time-dependent behavior of PVDF tested under combined static and cyclic loading conditions. It has been observed that the polymer has demonstrated accelerated creep rates due to cyclic loading effects. Cyclic creep acceleration in PVDF has been significant even in the range of stresses well below the viscoelastic linearity limit. This phenomenon, defined as "vibrocreep", appears to be essentially nonlinear, since the material response under combined static and cyclic loads did not represent a simple superposition of the responses to static and fully reversed cyclic loads applied separately. The second part of the paper provides a formulation of a nonlinear constitutive model, which describes the synergistic interaction between creep and cyclic damage evolution. The proposed constitutive model combines the concepts of linear hereditary viscoelasticity with damage characterization through a cyclic damage function. The latter is formulated using the basic principles of continuum damage mechanics. The potentials and limitations of the proposed constitutive model are discussed, and experimental results providing model validation are presented.
Muller, Dobzhansky, and overdominance

The most important issue on which H. J. Muller and Th. Dobzhansky differed was a question that had puzzled plant and animal breeders during most of the first half of the twentieth century. Breeders were concerned with maximizing performance. Dobzhansky was concerned with the potential of the species for further evolution and so was Muller, but his immediate concern was the impact on future generations of a radiation-induced increase in the mutation rate. All three concerns centered on how much of the genetic variability in the population depends on overdominance, that is, gene loci where the phenotype of a heterozygote is outside the range of the phenotypes of the two corresponding homozygotes. Heterosis, the greater vigor and performance of heterozygotes, attracted so much attention that in the summer of 1950 Iowa State College held a five-week symposium on the subject.' It will be helpful to make the vocabulary clear at the outset with an illustrative example:
Streamlining Field Data Collection With Mobile Apps

Fieldwork is a major component of nearly every geoscience discipline. Over the past 3 decades, scientists have amassed an array of specialized instrumentation and equipment to help them measure and monitor a staggering assortment of geophysical phenomena.
Biophysics of the leading lamella.

Several chapters in the proceedings have amply demonstrated that the biochemistry and structural biology of the leading lamella are complicated [Soll, 1988; Hartwig and Yin, 1988; Condeelis, et al., 19881. Therefore, I will approach the phenomenon of cell locomotion by posing two questions about the physics of this organelle: What are the mechanical forces that drive cell protrusion? How are the chemical and physical events coordinated? Too little is known to answer these questions definitively; but, enough is known to enable us to nominate some candidates. However complex the biochemistry of cell protrusion is, the cell must obey the laws of mechanics, which narrows the possibilities for protrusive forces much more than it constrains the chemical reactions that generate them. We now know that the plasma membrane-far from a simple oily film coating the cytoskeleton-is both a catalytic surface and a pool of reactants. The theme of my talk will be that the “control system” that directs cell protrusion resides in the cytoplasmic face of the membrane surrounding the leading lamella. Because this is not a “real” paper, but rather a rough transliteration of a talk, the format of my presentation will be bite-sized panels, each addressing a single issue. The diagrams in these panels are intended to be heuristic, not representational. Because my aim is to sion, adhesion, and retraction. Inherent in the properties of the leading lamella are many characteristics of cell locomotion; these include contact inhibition taxes: chemotaxis, haptotaxis, galvanotaxis substrate guidance 8 ruffles retraction induced spreading tension inhibition of spreading centripetal particle movement surging and steady spreading
Explicit formulation of titration models for isothermal titration calorimetry

Isothermal titration calorimetry (ITC) produces a differential heat signal with respect to the total titrant concentration. This feature gives ITC excellent sensitivity for studying the thermodynamics of complex biomolecular interactions in solution. Currently, numerical methods for data fitting are based primarily on indirect approaches rooted in the usual practice of formulating biochemical models in terms of integrated variables. Here, a direct approach is presented wherein ITC models are formulated and solved as numerical initial value problems for data fitting and simulation purposes. To do so, the ITC signal is cast explicitly as a first-order ordinary differential equation (ODE) with total titrant concentration as independent variable and the concentration of a bound or free ligand species as dependent variable. This approach was applied to four ligand-receptor binding and homotropic dissociation models. Qualitative analysis of the explicit ODEs offers insights into the behavior of the models that would be inaccessible to indirect methods of analysis. Numerical ODEs are also highly compatible with regression analysis. Since solutions to numerical initial value problems are straightforward to implement on common computing platforms in the biochemical laboratory, this method is expected to facilitate the development of ITC models tailored to any experimental system of interest.
Restoration of descending inputs fails to rescue activity following deafferentation of a motor network.

Motor networks such as the pyloric network of the stomatogastric ganglion often require descending neuromodulatory inputs to initiate, regulate, and modulate their activity and their synaptic connectivity to manifest physiologically appropriate output. Prolonged removal of these descending inputs often results in a compensatory response that alters the inputs themselves, their targets, or both. Using the pyloric network of the crab, Cancer borealis, we investigated whether isolation of motor networks would result in alterations that change the responses of these networks to restored modulatory input. We used a reversible block with isotonic sucrose to transiently alter descending inputs into the pyloric network of the crab stomatogastric ganglion. Using this method, we found that blocking neuromodulatory inputs caused a reduced ability for subsequently restored modulatory projections to appropriately generate network output. Our results suggest that this could be due to changes in activity of descending p...
Two algorithmic results for the traveling salesman problem

For any norm in a Euclidean space and for any number δ > 0 we present a polynomial time algorithm which computes a Hamiltonian circuit with the given vertices in the space whose length approximates, with relative error less than δ, the largest length of a Hamiltonian circuit with these vertices. We also present an algorithm which for a given graph with n vertices computes the number of Hamiltonian circuits in this graph with 2n+Olog n time complexity and a polynomial in n space complexity. As a by-product of our approach we prove that the permanent of a matrix can be computed in polynomial time provided the rank of the matrix is fixed.
Game Assessment: Fun as Well as Effective

Alternative methods of assessing student knowledge are useful since assessment is increasingly being emphasized by administrators, accrediting agencies and legislators. A game (team) format to assess students' knowledge of course material was experimentally compared with the traditional format of testing a student who answers individually. Team‐game scores were more often correct than individual scores in all comparisons. Team decisions, which involved cooperation within one's group while at the same time competing against other teams, were rarely the result of a single individual deciding on the team answer. Students preferred the game‐assessment condition more and also perceived it as a more accurate measure of their course knowledge.
The utility of trained arthritis patient educators in the evaluation and improvement of musculoskeletal examination skills of physicians in training.

Objective To determine the level of examination skills of internal medicine residents and to assess whether an intervention by trained persons with arthritis could have a greater impact on their examination skills than participation in an ambulatory care training experience. Methods Twenty-seven residents attended a 6-week ambulatory care rotation that included didactic teaching as well as attendance at an outpatient arthritis clinic with supervision by rheumatologists. Sixteen residents were randomly assigned to have a training encounter with an arthritis educator along with the standard experience in the arthritis clinic, whereas 11 residents received training in the arthritis clinic only. Arthritis educators evaluated the musculoskeletal examination skills of each resident during the first week of the rotation. The 16 residents in the intervention group received instruction on joint examination techniques by the arthritis educator immediately following their evaluation. At the end of the 6-week rotation, the groups were re-evaluated by a different arthritis educator. A group of 21 rheumatologists was also asked to perform a comprehensive musculoskeletal examination on individual arthritis educators. The arthritis educators assessed the examination of the rheumatologists using the same evaluation instrument that was used to assess the residents. Results Initially, internal medicine residents carried out the musculoskeletal examination poorly (34.2 ± 0.09% correct, n = 27). By contrast, the rheumatologists carried out a significantly greater amount of the examination correctly (54.5 ± 0.05%). The musculoskeletal examination skills of the residents who received additional training from an arthritis educator were significantly greater at the end of the rotation than the group who did not receive this intervention (50.5 ± 0.10% versus 41.9 ± 0.14% correct, P = 2.15 × 10−5). Conclusion Internal medicine residents carried out the musculoskeletal examination poorly. However, an intervention by arthritis educators improved the musculoskeletal examination skills of internal medicine residents significantly and more effectively than the standard clinical teaching in a rheumatology outpatient clinic. The impact of the arthritis educator intervention persisted for at least 5 weeks.
BDNF expression in perirhinal cortex is associated with exercise-induced improvement in object recognition memory

Abstract Physical exercise induces widespread neurobiological adaptations and improves learning and memory. Most research in this field has focused on hippocampus-based spatial tasks and changes in brain-derived neurotrophic factor (BDNF) as a putative substrate underlying exercise-induced cognitive improvements. Chronic exercise can also be anxiolytic and causes adaptive changes in stress-reactivity. The present study employed a perirhinal cortex-dependent object recognition task as well as the elevated plus maze to directly test for interactions between the cognitive and anxiolytic effects of exercise in male Long Evans rats. Hippocampal and perirhinal cortex tissue was collected to determine whether the relationship between BDNF and cognitive performance extends to this non-spatial and non-hippocampal-dependent task. We also examined whether the cognitive improvements persisted once the exercise regimen was terminated. Our data indicate that 4 weeks of voluntary exercise every-other-day improved object recognition memory. Importantly, BDNF expression in the perirhinal cortex of exercising rats was strongly correlated with object recognition memory. Exercise also decreased anxiety-like behavior, however there was no evidence to support a relationship between anxiety-like behavior and performance on the novel object recognition task. There was a trend for a negative relationship between anxiety-like behavior and hippocampal BDNF. Neither the cognitive improvements nor the relationship between cognitive function and perirhinal BDNF levels persisted after 2 weeks of inactivity. These are the first data demonstrating that region-specific changes in BDNF protein levels are correlated with exercise-induced improvements in non-spatial memory, mediated by structures outside the hippocampus and are consistent with the theory that, with regard to object recognition, the anxiolytic and cognitive effects of exercise may be mediated through separable mechanisms.
Numerical results for the thermal scattering functions

A recent formulation in radiative transfer defined the thermal scattering functions that characterize radiative transfer from a general plane-parallel finite medium driven solely by an internal distribution of thermal sources. Exiting diffuse intensities are expressed as space convolutions of the thermal scattering functions with any thermal source distribution. A parametric study is presented to obtain the basic structure of these scattering functions. The independent variables of these azimuthally independent functions are the direction cosine and source location, while the parameters are the single-scattering albedo, total optical depth, and the asymmetry factor in the Henyey-Greenstein phase function. The basic functional trends are discussed by using various parametric plots, and selected results are given to allow numerical checks. The computational method is invariant imbedding.
Selectivity isotherms for permeation of monovalent cations in gallbladder epithelium.

IN measuring transepithelial permeability ratios of cations in gallbladder, we have found that ‘biological variation’ among different individuals, between species and as a function of pH is not random but defines systematic patterns. These patterns, the so-called selectivity isotherms, are significant because they are in striking accord with Eisenman's1–3 theory of selectivity and because they provide a ‘fingerprint’ of the cation-selective membrane sites.
EPTATRETIN: A POTENT CARDIOACTIVE AGENT FROM THE BRANCHIAL HEART OF THE PACIFIC HAGFISH, EPTATRETUS STOUTII.

Abstract 1. 1. Isolation of a potent cardiac stimulant having marked pacemaker activity from the aneural branchial heart of the Pacific hagfish (Eptatretusstoutii) is described. The method developed involves preparation of a purified extract of the cardiac tissue with subsequent isolation of the cardioactive agent by elution from filter paper chromatograms and recrystallization from acetone. This material has been named “eptatretin” after the generic name of the fish whence it is obtained. 2. 2. Physical and chemical analyses have shown that eptatretin is apparently an amine or amide having certain characteristics of an aromatic compound. It is highly unstable when in crystalline form. Evidence is presented which indicates that eptatretin is definitely not a catecholamine or other commonly occuring biochemical. 3. 3. Comparative studies performed on hearts and other tissues of a number of organisms have revealed that eptatretin is apparently found only in the hagfishes. 4. 4. Pharmacological studies have revealed that eptatretin is a cardiac stimulant not only in lower forms but in the intact mammal (dog) as well. This obtains not only under normal but also certain abnormal situations. 5. 5. The possible role of eptatretin in cardiac automatism is discussed briefly.
Evaluation and treatment of HIV-related illnesses in the emergency department

Individuals infected with the human immunodeficiency virus (HIV) present frequently to emergency departments for treatment of complications. A working knowledge of the multisystem problems seen in HIV-infected patients is essential for the emergency physician. These problems are reviewed, with an emphasis on the respiratory, central nervous system, and gastrointestinal complications seen in patients with the acquired immune deficiency syndrome (AIDS). A practical approach is offered for management of febrile episodes and the other problems an emergency physician is likely to encounter.
Effect of corticosteroids on the dose response of surfactant in preterm rabbits

We injected 16 pregnant does with .1 mg/kg·day betamethasone (B) or vehicle (C) on the 2 days before C-section at day 27. The newborns were tracheostomized and randomly treated with normal saline (Sal), 5, 15, 30, or 50 mg/kg of rabbit surfactant (SA). They were then ventilated for 10 min with a ventilator-plethysmograph at tidal volumes of 12-15 ml/kg. After lung collapse, air pressure-volume inflation (Vi) and deflation (Vd) curves were measured from 0 (V0) to 35 cm H2O (V35) with volumes expressed as mean±SEM for ml/g dry lung wt and lung stability index (LSI) as (2V5±V10-3V0)/(2V35-2V0). There were significant differences for Vi35, Vd35, Vd15 and compliance between C and B at each dose (p<.01). The similarity of values for LSI between C and B showed that the steroid effect was not related to changing surface tension. Steroids have a threshold and synergistic effect on surfactant at low doses.
Graft force-setting technique in reconstruction of the anterior cruciate ligament

The objective of this work was to present a method for controlling the mechanical state of the knee during graft fixation in an ACL reconstruction; that is, adjusting the unloaded length of the graft at the time of fixation so that the force-carrying characteristics of the graft match that of the intact ACL, when the normal and recon structed knees are subjected to the same external load. To demonstrate the new method, an experimental knee testing system was used to measure ligament and graft forces with buckle transducers, as external loads were applied to five fresh knee specimens with a pneumatic load apparatus. ACL and collateral ligament force data were collected as anteriorly directed loads of 90 N (20 pounds) were applied at 0°, 30°, 60°, and 90° of flexion in the normal intact knee and the same knee following ACL excision. A composite graft was prepared, con sisting of distally based semitendinosus and gracilis autogenous tissue augmented with the Kennedy Liga ment Augmentation Device. Femoral fix...
Calculation of the dynamic impedance of the double layer on a planar electrode by the theory of electrokinetics.

Abstract Applications of microelectromechanical systems in the biotechnological arena (bioMEMS) are a subject of great current interest. Accurate calculation of electric field distribution in these devices is essential to the understanding and design of processes such as dielectrophoresis and AC electroosmosis that drive MEMS-based devices. In this paper, we present the calculation of the electrical double-layer impedance ( Z el ) of an ideally polarizable plane electrode using the standard model of colloidal electrokinetics. The frequency variation of the electrical potential drop across the double layer above a planar electrode in a general electrolyte solution is discussed as a function of the electrode zeta potential ζ, the Debye length κ −1 , the electrolyte composition and the bulk region thickness L.
New Experimental Test of Coulomb's Law: A Laboratory Upper Limit on the Photon Rest Mass

A high-frequency test of Coulomb's law is described. The sensitivity of the experiment is given in terms of a finite photon rest mass using the Proca equations. The null result of our measurement expressed in the form of the photon rest mass squared is ${\ensuremath{\mu}}^{2}=(1.04\ifmmode\pm\else\textpm\fi{}1.2)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}19}$ ${\mathrm{cm}}^{\ensuremath{-}2}$. Expressed as a deviation from Coulomb's law of the form $\frac{1}{{r}^{2+q}}$, our experiment gives $q=(2.7\ifmmode\pm\else\textpm\fi{}3.1)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}16}$. This result extends the validity of Coulomb's law by two orders of magnitude.
Computing the risky steady state of DSGE models

This note describes a simple procedure for solving the risky steady state in medium-scale macroeconomic models. This is the “point where agents choose to stay at a given date if they expect future risk and if the realization of shocks is 0 at this date” [Coeurdacier, N., Rey, H., Winant, P., 2011. The risky steady state. The American Economic Review 101 (3), 398–401]. This new procedure is a direct method which makes use of a second-order approximation of the macroeconomic model around its deterministic steady state, thus avoiding the need to employ an iterative algorithm to solve a fixed-point problem.
Sibling Pretend Play in Early and Middle Childhood: The Role of Creativity and Maternal Context

Research Findings: Sibling pretend play, collaboration, and creativity during maternal presence and absence were investigated in 24 dyads in early and middle childhood (younger siblings' M age = 5.3 years; older siblings' M age = 8.2 years). Associations between sibling behavior and maternal interaction (e.g., guidance, positive responses) were also examined. Creativity was assessed by (a) the number of object transformations, (b) pretense themes (set-up, typical, creative), and (c) use of descriptive language (i.e., adjectives). Findings indicated that maternal presence had an inhibitory impact on the frequency of sibling pretense, collaboration, and measures of creativity. Creativity measures were positively associated both within and across play sessions. Although maternal guidance was generally not associated with sibling interaction, maternal positive responses were associated with the younger sibling's behavior, suggesting that most mothers were responsive but not actively engaged in their children'...
A concise solution for shear flow problems in cylindrical geometry

A new development on theFN method for solving cylindrical flows problems in the field of rarefied gas dynamics is presented. The present approach is based on an integral-transform technique of the linearized Bhatnagar-Gross-Krook (BGK) model for shear flow and thus does not require availability of the exact elementary solutions of the shear flow equation.
Attractive Two-Body Interactions in Partially Ionized Plasmas

It has recently been shown that in a classical plasma a shielded Coulomb (Yukawa) potential describes the effective two-particle interactions through chains of intermediate particles. It therefore seemed reasonable to use this potential to approximate two-particle quantum interactions in a sea of charged particles, such as a hydrogen plasma. Consequently, an approximate solution of the Schr\"odinger equation was obtained for a hydrogen atom in a shielded Coulomb potential. With this potential, the number of H-atom bound states is finite and the energy eigenvalues are a function of the density and temperature. A variational calculation was performed using hydrogen-like single electron functions as a basis set and the effective nuclear charge as a variational parameter. Bound-state energies were obtained for 45 states of hydrogen in a gird of values for the screening constant. As the screening increases, the bound-state energy increases. For each state there is a maximum shielding above which the state is free, i.e., for which $Eg0$. According to the present calculation, the energy of the ground state becomes zero at a screening of 1.15 atomic units. Above this value then, no bound states can exist.
Single Nanoparticle Tracking Reveals Influence of Chemical Functionality of Nanoparticles on Local Ordering of Liquid Crystals and Nanoparticle Diffusion Coefficients

This letter reports that darkfield microscopy can be used to track the trajectories of chemically functionalized gold nanoparticles in nematic liquid crystals (LCs), thus leading to measurements of the diffusion coefficients of the nanoparticles in the LCs. These measurements reveal that the diffusion coefficients of the nanoparticles dispersed in the LC are strongly dependent on the surface chemistry of the nanoparticles. Because the changes in surface chemistry are measured to have negligible influence on the diffusion coefficients of the same nanoparticles dispersed in isotropic solvents, we conclude that surface chemistry-induced changes in the local order of LCs underlie the behavior of the diffusion coefficients of the nanoparticles in the LC. Surface chemistry-dependent ordering of the LCs near the surfaces of the nanoparticles was also found to influence diffusion coefficients measured when the LC was heated above the bulk nematic-to-isotropic transition temperature. These experimental measurements are placed into the context of past theoretical predictions regarding the impact of local ordering of LCs on diffusion coefficients. The results that emerge from this study provide important insights into the mobility of nanoparticles in LCs and suggest new approaches based on measurements of nanoparticle dynamics that can yield information on the ordering of LCs near nanoparticles.
Wild quotient singularities of surfaces

Let $$(B,\mathcal{M }_B)$$ be a noetherian regular local ring of dimension $$2$$ with residue field $$B/\mathcal{M }_B$$ of characteristic $$p>0$$ . Assume that $$B$$ is endowed with an action of a finite cyclic group $$H$$ whose order is divisible by $$p$$ . Associated with a resolution of singularities of $$\mathrm{Spec}B^H$$ is a resolution graph $$G$$ and an intersection matrix $$N$$ . We prove in this article three structural properties of wild quotient singularities, which suggest that in general, one should expect when $$H= \mathbb{Z }/p\mathbb{Z }$$ that the graph $$G$$ is a tree, that the Smith group $$\mathbb{Z }^n/\mathrm{Im}(N)$$ is killed by $$p$$ , and that the fundamental cycle $$Z$$ has self-intersection $$|Z^2|\le p$$ . We undertake a combinatorial study of intersection matrices $$N$$ with a view towards the explicit determination of the invariants $$\mathbb{Z }^n/\mathrm{Im}(N)$$ and $$Z$$ . We also exhibit explicitly the resolution graphs of an infinite set of wild $$\mathbb{Z }/2\mathbb{Z }$$ -singularities, using some results on elliptic curves with potentially good ordinary reduction which could be of independent interest.
Poverty and Depressed Mood Among Urban African-American Adolescents: A Family Stress Perspective

We examined the role of family stress as a mediator of the relationship between poverty and depressed mood among 1,704 low-income, inner-city African- American adolescents. Nearly half of participants (47%) reported clinically significant levels of depressive symptoms. Being female, reporting higher levels of family stress, and scoring higher on a poverty index were significantly associated with increased reports of depressed mood. Family stress significantly mediated the relationship between poverty and adolescent depressed mood, explaining 50% of the total effect. Sex-specific analyses revealed that this relationship only held for females, and there was no direct relationship between poverty and depressed mood for males. Results lend further support to family stress theory, although they suggest that the model may be more relevant for females than males. Implications for community-based preventive intervention and social policy are discussed.
Effective elastoplastic behavior of metal matrix composites containing randomly located aligned spheroidal Inhomogeneities. Part II: applications

Abstract Based on the proposed formulation in Part I of this sequel (Ju, J.W., Sun, L.Z., Int. J. Solids Struct. 38, 183–201), effective elastoplastic constitutive relations are implemented in this article for metal matrix composites (MMCs) with randomly located and unidirectionally aligned spheroidal particles. First, we investigate the uniaxial elastoplastic stress–strain behavior of MMCs. In particular, we perform comparisons among the theoretical uniaxial stress–strain predictions, existing finite element results and experimental data for MMCs to illustrate the capability of the proposed method. Furthermore, the effect of stress triaxiality is discussed under either the purely hydrostatic or axisymmetric loading on the overall elastoplastic behavior of composites. The proposed initial effective yield surfaces for composites are demonstrated and compared with those of the experimental data. As a special case of the incompressible ductile material containing aligned spheroidal voids, the initial effective yield criterion is studied and compared with that of mathematical upper bound. Finally, viscoplastic extension is briefly presented.
A deterministic¿stochastic hybrid model of downbursts and its impact on a cantilevered structure

Abstract Thunderstorm downbursts, which are sources of extreme wind loadings in nature, have caused numerous structural failures around the world. It is essential to build some applicable, though approximate, model for these loadings under which structures can be assessed. In this paper, a deterministic–stochastic hybrid model of downbursts is presented. In this model, downburst winds are the summation of a deterministic mean and a stochastic fluctuation. Wood’s velocity profile for the vertical profile and Holmes’ empirical model for the time function are utilized to model the mean wind. The fluctuation is modeled as a uniformly modulated evolutionary vector stochastic process. Time histories of downburst wind speeds over slender structures, such as tall buildings, can be simulated by the spectral representation method. Using the simulated downbursts as input, the dynamic responses of structures are obtained in the time domain. As a numerical example, the dynamic response of a cantilevered structure to simulated downbursts is computed and their sensitivity to the coherence function is discussed.
Translational research models and methods for mother-infant interactions and developmental studies.

The disruption of mother-infant interactions can have life-long detrimental consequences for offspring and mothers. Recently, science has begun to emphasize translational research including preclinical and neurobiological research that may have direct implications for clinical populations and issues (see Figure ​Figure1)1) (Watson et al., 2006). This group of papers focuses broadly on translational studies highlighting factors that may affect or alter infant or child development and maternal response capability. Articles, both preclinical and clinical, highlight topics such as drug abuse, maternal neglect, altered reward systems, stress, biological and neural system development, child and infant behavioral development, genetics/epigenetics, intergenerational studies, and logistical issues of comparative measurement. Articles include research methods papers, reviews, original research articles, techniques, and opinion articles that address these topics. New methods papers for comparative measures between clinical and preclinical populations are included. Our aims include introducing new translational models and methods for research through a group of outstanding papers focused on these topics. Figure 1 Approximate neuro-development comparison in humans (blue) and rats (orange; Watson et al., 2006). 1–6 = Myelination, 1 = myelination onset internal capsule, 2 = onset olfactory tract, 3 = onset anterior commissure, 4 = onset fornix, 5 = 50% ...
The presence of chlorophyll b in Synechocystis sp. PCC 6803 disturbs tetrapyrrole biosynthesis and enhances chlorophyll degradation.

Both chlorophyll (Chl) a andb accumulate in the light in a Synechocystissp. PCC 6803 strain that expresses higher plant genes coding for a light-harvesting complex II protein and Chl aoxygenase. This cyanobacterial strain also lacks photosystem (PS) I and cannot synthesize Chl in darkness because of the lack ofchlL. When this PS I-less/chlL−/lhcb +/cao +strain was grown in darkness, small amounts of two unusual tetrapyrroles, protochlorophyllide (PChlide) b and pheophorbide (pheide) b, were identified. Accumulation of PChlide b trailed that of PChlide a by several days, suggesting that PChlide a is an inefficient substrate of Chl a oxygenase. The presence of pheide b in this organism suggests a breakdown of Chl b via a pathway that does not involve conversion to a-type pigments. When the PS I-less/chlL− control strain was grown in darkness, Chl degradation was much slower than in the PS I-less/chlL−/lhcb +/cao +strain, suggesting that the presence of Chl b leads to more rapid turnover of Chl-binding proteins and/or a more active Chl degradation pathway. Levels and biosynthesis kinetics of Chl and of its biosynthetic intermediates are very different in the PS I-less/chlL−/lhcb +/cao +strain versus in the control. Moreover, when grown in darkness for 14 days, upon the addition of δ-aminolevulinic acid, the level of magnesium-protoporphyrin IX increased 60-fold in the PS I-less/chlL−/lhcb +/cao +strain (only ∼2-fold in the PS I-less/chlL−control strain), whereas the PChlide and protoheme levels remained fairly constant. We propose that a b-type PChlide, Chl, or pheide in the PS I-less/chlL−/lhcb +/cao +strain may bind to tetrapyrrole biosynthesis regulatory protein(s) (for example, the small Cab-like proteins) and thus affect the regulation of this pathway.
Semi-Automated Named Entity Annotation

We investigate a way to partially automate corpus annotation for named entity recognition, by requiring only binary decisions from an annotator. Our approach is based on a linear sequence model trained using a k-best MIRA learning algorithm. We ask an annotator to decide whether each mention produced by a high recall tagger is a true mention or a false positive. We conclude that our approach can reduce the effort of extending a seed training corpus by up to 58%.
Ambient and high-temperature thermal conductivity of thermal sprayed coatings

Aside from its importance as a design parameter for thermal barrier coatings, measuring thermal conductivity of thermal sprayed coatings itself provides a unique method to critically characterize the nature, quantity, and anisotropy of the defect morphologies in these splat-based coatings. In this paper, the authors present a systematic assessment of thermal conductivity of wide range using the flash diffusivity technique. For the case of plasma sprayed yttria-stabilized zirconia (YSZ), coatings obtained from wide-ranging initial powder morphologies as well as those fabricated under different particle states were characterized. Both in-plane and through-thickness properties were obtained. Other material systems that were considered include: metallic alloys and semiconductors of interests. Issues such as reproducibility and reliability in measurements were also considered and assessed. Finally, work in collaboration with the Oak Ridge National Laboratory (ORNL) for alternate approaches to characterization of thermal conductivity as well as high-temperature measurements was performed.
Stars in the Beginning

Loeb9s primer on the formation of early stars and galaxies opens a new series meant to offer short, accessible introductions to current frontiers of fundamental physics research.
SH3 Domains: Minding your p's and q's

SH3 domains mediate many important protein-protein interactions. The molecular basis of the binding of these domains to their ligands has been revealed, making it possible to identify SH3-binding sites in new proteins.
Perioperative issues in patients with cancer

The perioperative care of patients with cancer can be an exciting challenge. The physician must consider many factors, including the cancer diagnosis, the extent of disease, treatment received, the presence of comorbid conditions, and the patient's prognosis and must understand the impact of these factors on the planned surgical procedure. In this setting, the physician has the opportunity to perform an essential role in the perioperative management of patients with cancer.
Compliance with Parents’ Rules: Between-Person and Within-Person Predictions

The current study focused on the childhood to adolescence transition and sought to determine why some children are more compliant than others as well as why children comply more often with some of their parents’ rules than with others. Indices of parents’ agency and children’s agency were tested as predictors of compliance. Parent-based decision-making and parents’ responses to expressed disagreement served as indices of parents’ agency while children’s beliefs regarding the legitimacy of parents’ rules and felt obligation to obey rules served as indices of children’s agency. Parent–child dyads (n = 218; 51 % female, 49 % European American, 47 % African American) were interviewed during the summers following the children’s 5th (M adolescent age = 11.9 years) and 6th grade school years. Children who felt that their parents’ rules were more legitimate were more compliant overall than were children who felt that the rules were less legitimate. Children compiled more with rules governing topics perceived to be legitimately regulated by parents, when parents made more decisions regarding the topic and when parents responded to disagreement by standing strong. Results were generally consistent across parents’ and children’s reports of compliance and across cross-sectional and longitudinal analyses. At the transition from childhood to adolescence, only children’s agency explained why some children are more compliant than others, but parents’ and children’s agency helped to explain why children complied with some rules more than others.
Exploring adolescent's STEM learning through scaffolded game design

This paper presents the findings of two case studies concentrating on the learning experiences of disadvantaged middle school children participating in The Science and Art of Game Design (SAGD) and Globaloria, learning environments intended to teach skills in Science, Technology, Engineering, and Mathematics, through educational game design within informal and school-based settings.In SAGD, youth are introduced to the STEM principles underlying modern computer games through a two-part curriculum that takes a reverse engineering approach to educational game design. It begins with Gamestar Mechanic, a web-based role-playing game that encourages students to think of games as systems made up of game-specific components and principles that are learned by playing games, repairing dysfunctional games, and creating new ones for sharing and critique in an online communities [1]. The second part encourages them to learn to use these design principles and apply them to solving of problems requiring computational thinking [2] within the design of games centered on STEM subjects using Microsoft Kodu, a Microsoft 3D game creation tool.Globaloria is a learning environment designed for middle school classrooms where students learn STEM concepts in the process of learning to design computer games using the Adobe Flash platform. Globaloria classrooms are designed around constructionist pedagogies, and feature a project-based curriculum supported by a framework of Web 2.0 technologies, and an online community of school classrooms, educators, and professional game designers.Using multimodal content and discourse analysis, the study examined the evolution of students' STEM learning and literacy in these two contexts, as a function of their changes in language use, design strategies, and game artifact production. Findings suggest that scaffolded game design can provide an effective context for students to develop deep understandings and engagement with STEM subjects, in forms valued within the 21st century workplace.
The Chemistry of New Heat-Resistant Films and Fibers

This survey is principally concerned with papers published since 1959 on hydrocarbon polymers, aliphatic poly(terephthalamide) fibers, poly(hydroxybenzoic acid) films, poly(oxadiazole) fibers, poly(benzimidazole) films, poly(phenyltriazole) films, poly(pyromellitimide) films, and fibers from cyclized poly(acrylonitrile). All these materials have extremely high melting points and satisfactory in-use characteristics at high temperatures.
Multi-reflected echoes: Another ionogram signature of large-scale wave structure

[1] One or more steeply sloped traces have been found in evening ionograms taken from the Kwajalein Atoll (4.3°N dip latitude) during July 1979. Their resemblance to the normal F trace suggests that they are echoes that have undergone a large number of reflections from the F layer. These multi-reflected echoes (MREs) are interpreted in terms of focusing produced by curved isodensity contours in the bottomside F layer, which appear to be associated with large-scale wave structure (LSWS) that develops in the bottomside F layer. MREs appear to be another signature for LSWS, together with satellite traces that appear later in time, closer to the onset of plasma structure referred to as equatorial spread F. MREs are interesting because they display, for the data set examined, a strong preference to occur during the post-sunset rise of the F layer, which includes E-region sunset. How this finding affects our understanding of LSWS is discussed.
Design of neural nets with intermittent response and certain other relevant studies.

The application of the earlier results (Pavlidis, T. 1965. “A New Model for Simple Neural Nets and its Application in the Design of a Neural Oscillator.”Bull. Math. Biophysics,27, No. 2, 215–229) to the design of more complex neural nets is attempted. The following cases are considered: 1. Chains of neurons where it is proven that the frequency of the output pulses does not depend on the value of the input as long as it is above a certain threshold. 2. Groups of neurons with backward inhibition which present an intermittent mode of operation. 3. Neural nets with periodic facilitation which permit time sharing of certain components for different functions. 4. A neural net which can detect the sign of the input even if the main receptor is sensitive only to the absolute value of it, is presented. 5. A velocity estimating neural net which in combination with one of the nets with intermittent response provides a model for the smooth eye tracking movements.
The mechanism of ciliary movement. III. Theory of suppression of reversal by electrical potential of cilia reversed by barium ions

It is well known that Paramecium (1) is cathodally galvanotactic in mixtures of sodium and calcium salts because of ciliary reversal at the cathodal end, and that (2) the cilia also may be reversed in solutions rich in monovalent cations or in barium or manganese ions, and (3) the organisms swim backward in these solutions. It also is well known (Kamada, '31) that Paramecium in solutions of barium salts (4) is anodally galvanotactic at low electric potentials, (5) is cathodally galvanotactic at higher potentials, and (6) again becomes anodally galvanotactic if the potential is lowered, but these results have never been explained. However, they can be explained if the membrane is assumed to act as an ion exchanger. Cilia are reversed by barium because barium replaces some of the calcium on the membrane. When a low cathodal potential is applied, the barium, because of its high electrophoretic velocity (Ba++> Ca++> Na+) is removed, thereby causing a suppression of the reversal. If the potential is increased, calcium is also removed, leaving mostly sodium on the membrane, and this causes a return of the reversal. Lowering the potential again causes a suppression of the reversal. Changes at the anodal end can be explained in a comparable manner.
A Study in the Application of Socio-Psychological Research to the Problems of Business and Industry

(1948). A Study in the Application of Socio-Psychological Research to the Problems of Business and Industry. The Journal of Social Psychology: Vol. 27, No. 1, pp. 37-61.
Turbulence modelling over two-dimensional hills using an algebraic Reynolds stress expression

We carry out model studies of turbulence quantities for flow over two-dimensional hills using a non-hydrostatic version of the Regional Atmospheric Modeling System (RAMS). We test two turbulence closure models: the first one is an explicit Algebraic Reynolds Stress Model (ARSM) and the second one is a combination of the ARSM and a transport equation for the shear stress {ovuw}. Model predictions for the turbulent stresses are compared with data from a wind-tunnel experiment containing isolated two-dimensional hills of varying slope. From the comparison, it is concluded that the first model can only predict the normal stresses adequately while the second model provides satisfactory predictions for the normal stresses as well as giving an improved result for the shear stress {ovuw}.