cssi/SciSciGPT-SciSciNet huggingface dataset:
Amino acid neurotransmitters in the CNS. Relationships between net uptake and exchange in rat brain synaptosomes.

Carefully isolated, metabolically competent rat brain synaptosomes accumulate acidic amino acid neuro-transmitters down to very low external levels. This supports the suggestion that nerve endings are involved in terminating transmission at the synapses and in maintaining low levels of these molecules in the external environment in the brain. At saturating levels of acidic amino acids, the rate of inward and outward movements of the Na+-amino acid complex (exchange) is much faster than the net uptake. The transmembrane gradients of aspartate and glutamate approach each other under all conditions explored which indicates that these two amino acids share the same transport system.
PENNSYLVANIA'S EXPERIENCE IN THE COMPACTION OF ASPHALT PAVEMENTS

During 1974 through 1977, premature pavement distress in the form of loss of fines (matrix) and ravelling (loss of aggregate particle larger than 6.35 mm (1/4 in.)) was observed on several asphaltic concrete overlay projects in Pennsylvania. Statistically designed detailed investigations were conducted to determine the cause of this premature distress. Cores 152 mm (6 in.) in diameter were obtained at random and tested for density, air void content, mix composition, and rheological properties of the recovered asphalt. Lack of adequate compaction (high air void content) was determined to be the primary cause of distress. Nuclear control-strip techniques were used on these projects for compaction. The following data obtained from these investigations are included in the paper: (1) correlation of air void content with the extent of loss of fines and ravelling (rated as none, slight, moderate, and severe from field observations) and (2) correlation between the percent compaction data obtained by two methods (core density and nuclear gage density) at the same locations on the distressed pavements. Statistical analysis of the data from these projects indicated that (1) the percent compaction just after construction should be at least 92% of the maximum specific gravity of the mix to prevent the premature distress in the pavement and (2) the nuclear gage cannot be relied on completely by the user agency for acceptance purposes; it is most suited for compaction quality control by the contractor during construction. A statistical (end result) specification for compaction was developed and implemented by the Pennsylvania Department of Transportation in 1978. Density cores are obtained and tested at the central laboratory. The adoption of this compaction specification has resulted in a very significant improvement statewide in the initial compaction levels of asphalt pavements. The paper gives the outlines of this compaction specification, test procedures, and implications. The data on actual compaction levels (based on approximately 6000 core test) achieved statewide in 1981 have been analyzed statistically for both binder and wearing courses. (Author)
Etiology of nonspecific cause of death coding in New York City motor vehicle crash-related fatalities.

Objectives: Nearly 20 percent of New York City's (NYC) accidental deaths are related to motor vehicles crashes (MVCs). Detailed International Classification of Disease (ICD-10; World Health Organization [WHO] 2007) cause-of-death coding of MVC-related fatalities improves surveillance and resulting identification of prevention strategies. We investigated ICD-10 codes in these fatalities and the potential to make them more specific. Methods: We defined “nonspecific” MVC ICD-10 codes as all globally unspecific codes (V870–V878, V892) and any codes with nonspecific components regarding vehicle involved, decedent position in vehicle, or MVC setting. We calculated nonspecific-code frequency for 1999–2008 MVC deaths. We reviewed a random 10 percent sample of 2007–2008 MVC deaths (N = 61) and medical examiner (ME) records of all nonspecific death certificates (N = 52), including police accident reports (“full PAR”) and summaries prepared by onsite police officers (“brief PAR”) to determine whether MEs had suffici...
Intervalley scattering and field screening in germanium/silicon-germanium quantum wells

The scattering time of electrons from the direct Γ to the indirect L valley in the conduction band of germanium/silicon-germanium quantum wells is measured to be ∼250 fs. Carrier field screening is also observed and modeled.
High-Performance Gbit/s Data Transmission through Slow Light Elements

This paper will highlight various systems issues that relate to transmitting high-speed data through slow-light delay elements, such as: (i) data-pattern-dependent penalties, (ii) PSK and QPSK data signals, and (iii) synchronization and multiplexing.
Time-dependent current-density-functional theory for the linear response of weakly disordered systems

Time-dependent density-functional theory (TDFT) provides a way of calculating, in principle exactly, the linear response of interacting many-electron systems, and thus allows one to obtain their excitation energies. For extended systems, there exist excitations of a collective nature, such as bulk and surface plasmons in metals or intersubband plasmons in doped semiconductor quantum wells. This paper develops a quantitatively accurate first-principles description for the frequency and the linewidth of such excitations in inhomogeneous weakly disordered systems. A finite linewidth in general has intrinsic and extrinsic sources. At low temperatures and outside the region where electron-phonon interaction occurs, the only intrinsic damping mechanism is provided by electron-electron interaction. This kind of intrinsic damping can be described within TDFT, but one needs to go beyond the adiabatic approximation and include retardation effects. It has been shown [G. Vignale, C. A. Ullrich, and S. Conti, Phys. Rev. Lett. 79, 4878 (1997)] that a density-functional response theory that is local in space but nonlocal in time has to be constructed in terms of the currents, rather than the density. This theory will be reviewed in the first part of this paper. For quantitatively accurate linewidths, extrinsic dissipation mechanisms, such as impurities or disorder, have to be included in the response theory. In the second part of this paper, we discuss how extrinsic dissipation can be described within the so-called memory-function formalism. This formalism will first be introduced and reviewed for homogeneous systems. We will then present a synthesis of TDFT with the memory function formalism for inhomogeneous systems, which allows one to simultaneously account for intrinsic and extrinsic damping of collective excitations. As an example where both sources of dissipation are important and where high-quality experimental data are available for comparison, we discuss intersubband plasmons in a 40-nm-wide $\mathrm{GaAs}/{\mathrm{Al}}_{0.3}{\mathrm{Ga}}_{0.7}\mathrm{As}$ quantum well.
Consciousness, cognition, and communication

Awareness of our communication, of cognition and of consciousness itself remains one of the mysteries of the human experience. Consciousness seems central to our conception of what it means to be human, yet upon inspection appears to be peripheral to much of our communication and cognition. This paradox has been a central issue in the historic debate over determinism and free will and the recent debate over whether communication is largely intentional and/or conscious. Controversies continue over the nature of consciousness, the neural basis of consciousness and its relationship to communication, whether consciousness is unitary or dual, the benefits or harms of consciousness and its relationship to communication competence and pedagogy. In this essay the current state of thinking on these issues is critically examined.
Constitutive excitation by Gly90Asp rhodopsin rescues rods from degeneration caused by elevated production of cGMP in the dark.

Previous experiments indicate that congenital human retinal degeneration caused by genetic mutations that change the Ca2+ sensitivity of retinal guanylyl cyclase (retGC) can result from an increase in concentration of free intracellular cGMP and Ca2+ in the photoreceptors. To rescue degeneration in transgenic mouse models having either the Y99C or E155G mutations of the retGC modulator guanylyl cyclase-activating protein 1 (GCAP-1), which produce elevated cGMP synthesis in the dark, we used the G90D rhodopsin mutation, which produces constitutive stimulation of cGMP hydrolysis. The effects of the G90D transgene were evaluated by measuring retGC activity biochemically, by recording single rod and electroretinogram (ERG) responses, by intracellular free Ca2+ measurement, and by retinal morphological analysis. Although the G90D rhodopsin did not alter the abnormal Ca2+ sensitivity of retGC in the double-mutant animals, the intracellular free cGMP and Ca2+ concentrations returned close to normal levels, consistent with constitutive activation of the phosphodiesterase PDE6 cascade in darkness. G90D decreased the light sensitivity of rods but spared them from severe retinal degeneration in Y99C and E155G GCAP-1 mice. More than half of the photoreceptors remained alive, appeared morphologically normal, and produced electrical responses, at the time when their siblings lacking the G90D rhodopsin transgene lost the entire retinal outer nuclear layer and no longer responded to illumination. These experiments indicate that mutations that lead to increases in cGMP and Ca2+ can trigger photoreceptor degeneration but that constitutive activation of the transduction cascade in these animals can greatly enhance cell survival.
The Monument, or, Christopher Wren's Roman Accent

To commemorate the Great Fire, the Corporation of London commissioned Christopher Wren to design the Monument. This article identifies its formal sources in ancient Roman triumphal columns and in a sixteenth-century fluted Tuscan Doric column in Paris, in the inscription on the Column of Trajan, and in a passage from Ammianus Marcellinus. Textual models for the Latin inscriptions on the pedestal include Suetonius's Augustus, Seneca the Younger's Epistle no. 91, and Tacitus's Annals. The political situation in Restoration England cast references to Tacitus into oblivion, yet this commission demonstrates how Wren's knowledge of Latin had a determining effect on his architectural practice.
Optimization of replenishment policies for decentralized and centralized capacitated supply chains under various demands

Abstract In this paper, the optimal replenishment policies of capacitated supply chains (SC) operating under two different control strategies (decentralized vs. centralized) and various demands are determined and insights useful to management are discussed. The details of the system used, including the underlying supply chain inventory model and the simulation-based optimization framework, are presented. The effectiveness and efficiency of the proposed optimization framework is illustrated by comparing it with brute force estimation of the true optimum on three selected scenarios. The entire study was carried out by following a design of experiment, covering ten demand patterns, four levels of capacity constraints, and two control strategies. The main and two-factor interaction effects were analyzed via ANOVA. Detailed analyses of the ordering patterns, cost distribution over the SC and internal service level were carried out to provide useful insights. For demand with high variation, capacity constraint may lead to significant changes in ordering patterns. Failing to detect those changes may lead to unnecessary cost increase. Overall it is beneficial to adopt centralized control and cost savings realized are dependent upon the demand patterns. An incentive mechanism is proposed to coordinate the decentralized system so that each player in the SC will be better off. Additional experiments were also carried out to investigate the effect of using different allocation rules by the distributor.
Persistent One-Dimensional Face-to-Face π-Stacks within Organic Cocrystals

A general method for directing the formation of one-dimensional face-to-face π-stacking in the solid state that is based on supramolecular ladders within organic cocrystals is described.
Global/local analysis of composite plates with cracks

This paper presents a simple and accurate global-local method to calculate the static response of simply-supported, composite plates with small cracks. The approach primarily involves two steps. In the first step a global approach, the Ritz method, is used to calculate the response of the structure. Displacement based Ritz functions for the plate without the crack are augmented with a perturbation function, which is accurate for isotropic plates only, to account for the crack. The Ritz solution does not accurately satisfy the natural boundary conditions at the crack boundary. Therefore, a second step, local in nature, is taken in which a small area in the vicinity of the crack and encompassing other points of singularities, is discretized using a fine finite element mesh. The displacement boundary conditions for the local region are obtained from the global Ritz analysis. The methodology is applied for the local model including the crack. The proposed approach resulted in accurate prediction of stresses, with 85% savings in computational time and 92% in data storage for the analysis of composite flat panels.
Some remarks on subdynamics for systems interacting with reservoirs

Abstract It is shown that collision operators defined by the projector of Argyres and Kelley may provide useful examples for study of the subdynamics of the Brussels group. An application of this formalism to the optical pumping model of Barrat and Cohen-Tannoudji is discussed.
On radiant energy in high-temperature research

Abstract The mechanism of heating solids with radiant energy is reviewed and the need for measuring radiative properties is pointed out. Image furnaces are suitable for such measurement at high temperatures. The limitations of image furnace operations are discussed and methods as well as equipment offered to overcome the limitations. The importance of artificial black bodies in high-flux measurements is described and a new shape for such cavities is proposed. Data comparing this shape with hitherto used shapes are tabulated. Design for a fast-action on-off shutter for image furnaces is presented. In its retracted position the shutter does not cast any shadow on the mirror and it does not require artificial cooling even when exposed to radiation.
Fab FM: the design, making, and modification of an open-source electronic product

This paper explores the ways in which digital fabrication allows for the small-scale manufacture and individual customization of consumer electronic products. We present Fab FM, an open-source FM radio that integrates an electronic circuit board, laser-cut wood, and fabric. We describe a workshop in which participants designed and built their own Fab FM variants, modifying the form, materials, and behavior of the radio. Drawing from this experience, we discuss three themes: the issues involved in working across design domains, the ways in which design can serve as source code, and the difference between open- source and hackable. We present potential business models for Fab FM, and discuss the possibilities that digital fabrication offers for a more diverse landscape of high-tech products.
An Approach to Mitigating Unwanted Interactions between Search Operators in Multi-Objective Optimization

At run time, software systems often face a myriad of adverse environmental conditions and system failures that cannot be anticipated during the system's initial design phase. These uncertainties drive the need for dynamically adaptive systems that are capable of providing self-* properties (e.g., self-monitoring, self-adaptive, self-healing, etc.). Prescriptive techniques to manually preload these systems with a limited set of configurations often result in brittle, rigid designs that are unable to cope with environmental uncertainty. An alternative approach is to embed a search technique capable of exploring and generating optimal reconfigurations at run time. Increasingly, DAS applications are defined by multiple competing objectives (e.g., cost vs. performance) in which a set of valid solutions with a range of trade-offs are to be considered rather than a single optimal solution. While leveraging a multi-objective optimization technique, NSGA-II, to manage these competing objectives, hidden interactions were observed between search operators that prevented fair competition among solutions and restricted search from regions where valid optimal configurations existed. In this follow-on work, we demonstrate the role that niching can play in mitigating these unwanted interactions by explicitly creating favorable regions within the objective space where optimal solutions can equally compete and co-exist.
Simultaneous ultrafiltration and affinity sorptive separation of proteins in a hollow fiber membrane module

A protein separation scheme combining affinity or ion exchange sorption with hollow fiber cross-flow filtration is described. Sorptive gel particles were loaded into the shell side of a hollow fiber membrane module. In the adsorption step, crude protein mixtures were passed through the lumen and permeating proteins passed through the membrane to bind on the gel particles in the shell. During elution, a buffer of adequate ionic strength to desorb the bound proteins was passed through the lumen and permeated through the shell. The eluant was then collected at the outlet to the shell of the hollow fiber module. The concept is illustrated by two examples: the purification of butyrylcholinesterase (EC 3.1.1.7) from raw horse serum using the affinity gel procainamide-Sepharose as the packing and the separation of carboxylesterase (EC 3.1.1.1) from beef liver homogenate using DEAE-Sephadex as the packing. The technique has the advantage of high volumetric throughputs typical of hollow fiber membrane modules as well as the high capacity characteristic of chromatographic packings. In addition, cross-flow filtration of particulates, agglomerates, and debris in passing protein from lumen to shell side can help eliminate the need for extensive pretreatment.
Germination Inhibition of Alfalfa by Two‐Component Salt Mixtures

Soil and water salinity can severely constrain agricultural production by reducing plant stands and growth. Breeders have used germination in saline (NaCl) media to screen plant germplasm for salt tolerance. However, salt tolerance during germination in NaCl may not adquately describe the ability of seeds to germinate in mixtures of salts. Naturally occuring combinations of salts may be more or less inhibitory than the individual salts alone. The objective of this research was to quantify the effects of individual as well as two-component mixtures of various salts and ions on the seed germination of alfalfa (Medicago sativa L.) [...]
Hydrographic control of the marine ecosystem in the South Shetland-Elephant Island and Bransfield Strait region

The South Shetland-Elephant Island and Bransfield Strait region of the West Antarctic Peninsula is an important spawning and nursery ground of Antarctic krill (Euphausia superba) and is an important source of krill to the Southern Ocean. Krill reproductive and recruitment success, hence supply of krill to predator populations locally and in downstream areas, are extremely variable on interannual and longer time scales. Interannual ecosystem variability in this region has long been recognized and thought related to El Nino Southern Oscillation (ENSO) events, but understanding of how has been limited by the hydrographic complexity of the region and lack of appropriate ocean-atmosphere interaction models. This study utilizes multidisciplinary data sets collected in the region from 1990 to 2004 by the U.S. Antarctic Living Marine Resources (AMLR) Program. We focus on hydrographic conditions associated with changes in the distribution, abundance and composition of salp- and copepod-dominated zooplankton assemblages during 1998 and 1999, years characterized respectively by a strong El Nino event and La Nina conditions. We provide detailed analyses of hydrographic, biological and ecological conditions during these dichotomous years in order to identify previously elusive oceanographic processes underlying ecosystem variability. We found that fluctuations between salp-dominated coastal zooplankton assemblages and copepod-dominated oceanic zooplankton assemblages result from the relative influence of Weddell Sea and oceanic waters and that these fluctuations are associated with latitudinal movement of the Southern Antarctic Circumpolar Current Front (sACCf). Latitudinal movements of the sACCf can be explained by meridional atmosphere teleconnections instigated in the western tropical Pacific Ocean by ENSO variability and are consistent with out-of-phase forcing in the South Pacific and South Atlantic Oceans by the Antarctic Dipole high-latitude climate mode. During El Nino decreased northwest winds, equatorward movement of the sACCf and an intensified Weddell Gyre allow Weddell Sea water to flow into eastern Bransfield Strait. During these periods mixing between oceanic and coastal waters is reduced, chlorophyll a concentrations are low, salps numerically dominate the zooplankton, and krill recruitment success is poor. During La Nina increased and more frequent northwest winds and poleward movement of the sACCf allows increased influence of oceanic waters and mixing of these with cold coastal waters. These periods are characterized by numerical dominance of copepods, elevated concentrations of oceanic zooplankton taxa and phytoplankton blooms that promote krill reproduction and recruitment success. Hydrographic and ecological changes after the 1998 El Nino are associated with a shift from frequent El Ninos to the prevalence of La Nina and neutral conditions and conform to a decadal-scale climate regime shift in the Antarctic Peninsula region.
Commentary on Prothro's Content Analysis.

James W. Prothro's hypothesis is that, while there has been a resurgence of "conservatism" in American political theory and practice, the actual intervention of the New Deal between the conservative government of Hoover and the conservative government of Eisenhower makes the complete rejection of New Deal appeals by a conservative administration difficult, if not impossible. There can be little quarrel with that thesis itself. Once given the assumptions that "conservatism" is an adequate frame of reference, that Hoover and Eisenhower may in some understandable way be classed as "conservatives," and that, since the administration did in fact reluctantly accept certain New Deal symbols, they were necessarily obliged to do so, there is some question as to whether the thesis is not obvious. Prothro, however, gives serious reasons for buttressing "impressions" with precision, and presents a careful content analysis which strengthens his argument and should serve to enhance our understanding of current political trends. His presentation, however, raises at least three meaningful questions: whether "conservatism" is an adequate frame of reference for the discussion of political ideas, whether content analysis is a sound method for distinguishing political ideas, and whether, and under what conditions, it is useful to give scientific precision to "impressions." In exploring these questions I do not propose to I)ick a quarrel with Prothro. Differences will come out in the discussion, but the larger problems relate to the general study of political theory, and the exploration may at times take me far from the specific questions raised in Prothro's scholarly paper. I fully sympathize with the author's impatience with those who reject the scientific method on purely aesthetic grounds. By all means let us seek precision, as far as that can be had, on all levels of investigation.
Chiral Optical Properties of a Helical Polymer Synthesized from Nearly Racemic Chiral Monomers Highly Diluted with Achiral Monomers

In polyisocyanates composed only of randomly distributed (R) and (S) units, the chiral optical properties of the polymer are far out of proportion to the enantiomeric excess of the monomers. This highly disproportionate relationship, which arises from a majority-rule effect among these enantiomeric units on the helical sense of the backbone, is now found to be unaffected, within certain limits, by the overwhelming presence of achiral units randomly distributed along the chain. This experimental result can be explained quantitatively by an analysis based on the one-dimensional random-field Ising model, which shows that dilution of the chiral units with achiral units increases the helical domain size in a manner that compensates for the dilution. In qualitative terms, since the random-field domain size is limited by the "objection" of the minority units to the helical sense dictated by the majority units, dilution of this "objection" acts to increase the domain size. As long as this domain size is not limited by the chain length or by thermal fluctuations, the achiral dilution will not reduce the optical activity of the polymer.
Ultrasound-guided pediatric liver transplant biopsy using a spring-propelled cutting needle (biopsy gun).

Biopsy is the best way to diagnose allograft rejection, the most common complication following liver transplantation. The authors reviewed 99 consecutive ultrasound-guided cutting needle biopsies in 19 infants and children. Conscious sedation was used with 95 biopsies. General anesthesia was used with four biopsies, all in patients undergoing percutaneous biliary procedures at the same time. Ninety-eight biopsies were diagnostic. Only one major complication occurred: biloma. Ultrasoundguided cutting needle biopsy of pediatric liver transplant patients can be performed safely and efficaciously.
Suppression of dispersion in FDTD solutions of Maxwell's equations

Yee's finite difference time-domain method is widely used for numerically solving Maxwell's equations. The Yee algorithm is numerically dispersive which limits its usefulness for modeling wide-band electromagnetic phenomena. In this paper, we describe the use of flux-corrected transport for suppressing the numerical dispersion associated with the Yee algorithm. Flux-corrected transport uses the computed results from a numerically dispersive finite-difference algorithm and a numerically diffusive finite-difference algorithm at each time step to arrive at a final solution. In this case, the dispersive algorithm used is the original Yee FDTD method. Results are given comparing the accuracy of the FDTD algorithm with flux-corrected transport versus the unmodified Yee algorithm for propagating pulsed-type plane waves in two dimensional scattering problems.
The Phenomenology of Hairpulling in College Students

This study examined the phenomenology of hairpulling in a large nonclinical college student sample. Given that hairpulling is conceptualized as occurring on a continuum of severity, we expected to inform the assessment and treatment of Trichotillomania (TTM) by examining hairpulling behavior across its range of presentation. Hairpulling occurred at a rate of 9.7%, while average age of onset was 13.57 years. Self-reported hairpulling styles were identified with 31.3% endorsing focused hairpulling, while 68.7% endorsed an automatic hairpulling style. The most commonly endorsed ritual was “examine the root (37.3%) while the scalp was the most frequently endorsed hairpulling site (49%). Eyelashes were more frequently endorsed as a pulling site by focused (43.8) compared to automatic (5.7%) hairpullers. The hairpulling environments most often endorsed were “while reading” and “while studying” (75%). Affective states were found to change across the pulling cycle in support of hairpulling serving in an emotion regulation capacity. Focused hairpullers endorsed significantly higher trait anxiety than automatic hairpullers. Depression scores (BDI) were elevated for hairpullers compared to non-hairpullers. Implications for assessment and treatment were discussed and directions for future research were provided.
Longitudinal Gompertzian analysis of amyotrophic lateral sclerosis mortality in the U.S., 1977-1986: evidence for an inherently susceptible population subset

Age-adjusted mortality rates for amyotrophic lateral sclerosis (ALS) for men and women in the United States from 1977 to 1986 were determined and subjected to longitudinal Gompertzian analysis. The exponential decline in the rate of increase of age-adjusted ALS mortality rates after age 55 years is most consistent with the existence of an inherently susceptible population subset that is decreasing faster than the general population. In the U.S. between 1977 and 1986, annual age-adjusted ALS mortality rate distributions were determined by a common fixed intersect point (for men, the death rate at age 46.38 years was 0.91/100,000; for women, the death rate at age 45.85 years was 0.46/100,000); and an environmental factor that varied erratically during the decade by a factor of 7.21 for men and 11.64 for women. On the average, the U.S. environment during this period was 4.33 times more conducive to mortality from ALS in men than in women. Overall ALS mortality between 1977 and 1986 increased 46% and 49% for men and women, respectively. The common fixed intersect point in mortality rate distributions suggests that these increases were real and not merely the result of improved diagnosis and/or better reporting. The overall increase in ALS mortality most likely results from an effective increase in the susceptible population subset due to increasing life expectancy, rather than to environmental factors. That is, as life expectancy increases, more of the susceptible population subset live long enough to express the disease.
Comparative Ab Initio study of electronic and ionic properties of lithium nitride (Li3N), lithium phosphide (Li3P), and lithium arsenide (Li3As)

Ab initio Hartree–Fock band structure calculations are presented for the first time for lithium phosphide (Li3P) and lithium arsenide (Li3As) in the hexagonal P6/mmm crystal structure. Results are compared to those for lithium nitride (Li3N). The new calculations for Li3N agree with previous Hartree–Fock calculations, except for the valence band structure where results of previous pseudopotential calculations are confirmed. Geometry optimization for Li3P yields a lattice parameter a of 4.45 A and a c value of 4.80 A. These values differ markedly from experimental results reported to be 4.271 and 7.590 A, respectively. A similar discrepancy is found for lithium arsenide: a = 4.60 A and c = 4.96 A have to be compared to the reported experimental values of 4.397 A for a and 7.824 A for c. Force constants are derived for in-plane and interplane vibrations. The band structures for Li3P and Li3As are found to be very similar to the one calculated for Li3N. Using Li3P as an example, it is shown how the band structure of the insulator can be derived from the band structures of the two metallic constitutent Li2P and Li monolayers. The metal–insulator transition occurs if the inter-plane distance falls below 4.25 A. Contrary to expectations raised earlier, it is found that the 3d electrons in arsenic are strongly localized, evidenced by a very narrow d band width of 0.1 eV. They cannot be used to explain the difference in conductivity between the phosphide and the arsenide. A Mulliken population analysis gives charge distributions close to the ideal ionic structure (Li+)3X3−, X = N, P, and As. Overall it is found that hexagonal lithium phosphide and lithium arsenide arsenide are more similar to lithium nitride and less anisotropic than suggested previously. This discrepancy could be due to the use of polycrystalline samples in earlier experiments.
Attachments to Family and Community and the Young Adult Transition of Rural Youth

Rural youth in economically troubled regions develop plans for their future in a context in which opportunities for educational and occupational success generally lie elsewhere, prompting the need to migrate. This study investigates the links between rural adolescents' residential preferences and their plans for the future, perceptions of local opportunity, and ties to family and community. We examine whether residential preferences shape the pathways to adulthood through decisions about where to live as well as educational and occupational attainments. Residential preferences are indeed related to adolescents' academic achievements and future educational plans, their relationships with parents, and perceptions of local job opportunities, but they are not associated with family socioeconomic background and social ties to the community. For the most part, residential preferences are linked to where young people live and pursue higher education in the years after high school, but generally not to their socioeconomic attainment.
Laser-induced fluorescent cooling of rare-earth-doped fluoride glasses

Continual cooling of a material by anti-Stokes luminescence has been experimentally observed in a solid material. Net cooling was achieved by pumping to the lower levels of the 2F5/2 manifold of Yb3+, followed by population redistribution across this manifold via thermalization and fluorescence to the ground state. Fluoride glass hosts in the ZBLAN and BaF2–InF3–GaF3 (BIG) families have been used in these experiments. Temperature decreases of 0.33 K in a bulk glass sample and 16 K in a fiber sample were obtained in ZBLANPb:Yb3+. Net cooling was achieved when an electrochemical purification stage was incorporated into the glass fabrication process to decrease the extrinsic absorptive component of the host glass in the 1.0 μm region. Resonant laser ablation experiments showed the positive and negative effects of electrochemical processing on fluoride glasses in reducing transition metal content which is detrimental to successful fluorescent cooling. Reduction in copper, iron, and chromium content of 18, 4.2, and 5.5 were determined for the ZBLANPb sample via RLA. However, reductions in transition metal content were only 1.9 for copper and a negligible amount for iron and chromium in the BIG glasses.
Model-Based Sliding Mode Control for a Robot With SMA Actuators

ABSTRACT This paper presents a model-based sliding mode control law for a planar three-degree-of-freedom robot arm actuated by two rotary Shape Memory Alloy (SMA) actuat ors and a servomotor. The SMA actuators use a combination of SMA wires and pulleys to produce rotational motion. A model of the robot is developed which combines robot equations of motion with the SMA wire heat convection, constitutive law, and phase transformation equations. Two second-order sliding surfaces are defined leading to derivation of asymptotically stable co ntrol laws within the actuation region of the SMA wires. Outside the actuation region, constant inputs are used based on the one-way nature of the SMA actuators. The control law is shown to be effective in several simulations for both set point and trajectory tracking of the robot. Introduction Shape Memory Alloy (SMA) actuators have certain advantages that makes them suitable for robotics applications [1-2] including high power to mass ratio, lack of frictional parts, silence, and simplicity of their mechanisms. However, precise motion control, speed, and efficiency of these actuators have remained problematic. Control difficulties generally arise from large uncertainties in the macro-model of the actuator and delays in response due to dependency of the actuation on heating and cooling of the material. Considerable research for modeling the microscopic and macroscopic behavior of shape memory alloys has been performed in past forty yea rs. Since the mechanical behavior of shape memory alloys is closely related to microscopic phase transformation (between Martensite and Austenite phases), constitutive relatio n are ot merely stress-strain based andmustinclude phase transformation and heat transfer characteristics [3-5]. Mre recently researchers have developed Preisach model ing met h ods ad accunte fr bt maj r and mnohysteresis loops to overcome precision control difficulties associated with SMA actuators [6]. In the controls area, researchers have explored linear controllers as well as Pulse Wid th Modulatio n, optimal co rol, fuzzy logic, and variable structu re and sl id ng mode control a poaches [7-15]. Amothese sl id g mode cont ro lhas sh w p omi sng resu because of significant parameter uncertainties in SMA models. In this work, we derive present an asymptotically stable sliding mode control law for an in-house three-link planar robot arm actuated by a combination of two bias type SMA actuators and a servomotor. The control law is based on a model of the robot that includes coupled robot equations of motion and SMA constitutive law, heat convection, and phase transformation. Two second-order sliding mode surfaces are defined leading to derivation of a control law which guarantees asymptotic stability when the SMA actuators are within the actuation region defined based on the alloy’s stress and temperature. Simulations are performed to show that the control law is able to accurately position the robot in both set point and trajectory tracking cases.
Measurement of the expansion of picosecond laser-produced plasmas using resonance absorption profile spectroscopy.

Time-resolved, submicron density scale lengths in picosecond laser-produced plasmas are measured using resonance absorption profile spectroscopy. The density scale length at critical density is inferred from the angle and polarization dependence of the absorption of a picosecond laser pulse in a performed plasma. The early expansion of picosecond laser-produced plasmas produced from an Au target is studied, with measured scale lengths in the range of \ensuremath{\sim}1000\char21{}5000 A\r{}.
Design and characterization of Si and InGaAs pyrometers for radiance temperature scale realization between 232 °C and 962 °C

New transfer standard pyrometers, named "RT900" and "RT1550," operating at 900 nm and 1550 nm, respectively, have been designed, characterized, and calibrated with defined fixed points of the International Temperature Scale 1990 (ITS-90) at the National Institute of Standards and Technology (NIST). The pyrometers are designed for radiance temperature measurements in the range between the freezing temperatures of Sn (231.928 °C) and Ag (961.78 °C). These instruments also incorporate design elements optimized for compactness and portability that allow them to be used to interpolate, maintain and disseminate radiance temperature scales as well as for inter-laboratory comparisons. The calibration of the RT900 at different fixed points demonstrate agreement to within 25 mK. The size of source effect (SSE) correction for a source with a 40-mm diameter has been measured to be as low as 0.01 %.
Traditional Knowledge and Intellectual Property

Biotechnological inventions are sometimes based upon the traditional knowledge of indigenous communities about the beneficial properties of plants and animals. Some institutions have adopted the uniqueness of traditional knowledge approach, which maintains that the indigenous communities have sui generis rights to a share of the profits from these inventions. Others have adopted the protection of inventive steps approach, which maintains that the inventors are entitled to the full profits from the invention if it involves a non-obvious and novel inventive step. The article analyzes this debate at the Convention on Biological Diversity, at the World Intellectual Property Organization, and at the World Trade Organization. It concludes that the adherents of the uniqueness of traditional knowledge approach have not justified their claims.
Intermittent short‐duration magnetic field anomalies in the Io torus: Evidence for plasma interchange?

On Galileo's inbound pass through the Io plasma torus in December 1995, we detected intermittent, short-duration increases in the magnetic field magnitude, notable by their abrupt onset and subsequent abrupt recovery to the previous level. The events were small and brief, with an average field change of 15.7 nT (1–2% of the background field) and an average duration of ∼26 s. They were observed first shortly after data at high time resolution were first acquired at a radial distance of 7.7 RJ from Jupiter's center. The last and most clearly-defined signature, with exceptionally sharp boundaries, was observed at 6.03 RJ, about 12 minutes before closest approach to Io. The magnetic pressure change across the boundaries of these structures was ∼10 to ∼33 nPa, the latter value in a region with background plasma pressure of 60 nPa. Thus, although of small amplitude in the magnetic field, they represent large changes in the pressure. Abrupt changes in the measurements of the other fields and particles instruments correlate with some of the magnetic signatures. In this paper, we present the magnetometer data for these unusual signatures, discuss the limits on particle density changes that they imply, the significance of their spatial distribution, and their relationship to transport of plasma in the torus.
Comparative Evaluation of ProEx C and ImmunoCyt/uCyt Assays in Atypical Urine Cytology

Context.—Detection of urothelial carcinoma by urine cytology can be challenging. Recently, ProEx C has been studied as a marker to improve detection of urothelial carcinoma. ProEx C is an assay targeting expression of topoisomerase II-α and the minichromosome maintenance protein-2 and is used to assist in diagnoses of gynecologic specimens. Objective.—To evaluate the utility of ProEx C and uCyt in atypical urine cytology. Design.—Sixty-eight specimens with a diagnosis of atypical urine cytology, concurrent uCyt testing, and surgical biopsy follow-up were included. Slides were restained with ProEx C. ProEx C was recorded as positive when nuclear staining was seen in at least one morphologically atypical urothelial cell. The uCyt was scored as positive if at least one morphologically atypical urothelial cell showed positive fluorescence staining. Thirteen cases (19%) had benign histologic diagnoses, 18 (26%) had low-grade papillary urothelial carcinoma, and 37 (54%) had high-grade urothelial carcinoma. Resu...
Development of a mouse test for repetitive, restricted behaviors: relevance to autism.

Abstract Repetitive behavior, a core symptom of autism, encompasses stereotyped responses, restricted interests, and resistance to change. These studies investigated whether different components of the repetitive behavior domain could be modeled in the exploratory hole-board task in mice. Four inbred mouse strains, C57BL/6J, BALB/cByJ, BTBR T+tf/J, and FVB/NJ, and mice with reduced expression of Grin1, leading to NMDA receptor hypofunction (NR1neo/neo mice), were tested for exploration and preference for olfactory stimuli in an activity chamber with a 16-hole floor-board. Reduced exploration and high preference for holes located in the corners of the chamber were observed in BALB/cByJ and BTBR T+tf/J mice. All inbred strains had initial high preference for a familiar olfactory stimulus (clean cage bedding). BTBR T+tf/J was the only strain that did not demonstrate a shift in hole preference towards an appetitive olfactory stimulus (cereal or a chocolate chip), following home cage exposure to the food. The NR1neo/neo mice showed lower hole selectivity and aberrant olfactory stimulus preference, in comparison to wildtype controls. The results indicate that NR1neo/neo mice have repetitive nose poke responses that are less modified by environmental contingencies than responses in wildtype mice. 25–30% of NMDA receptor hypomorphic mice also show self-injurious responses. Findings from the olfactory studies suggest that resistance to change and restricted interests might be modeled in mice by a failure to alter patterns of hole preference following familiarization with an appetitive stimulus, and by high preference persistently demonstrated for one particular olfactory stimulus. Further work is required to determine the characteristics of optimal mouse social stimuli in the olfactory hole-board test.
Primary Cutaneous B-Cell Lymphomas

B-cell lymphomas occurring in the skin often tend to be of systemic origin with secondary cutaneous involvement. Primary cutaneous B-cell lymphomas tend to be indolent disorders, with the exception of primary cutaneous diffuse large B-cell lymphoma-leg type (PCDLBCL-LT). In indolent conditions, the distinction between cutaneous lymphoma and cutaneous lymphoid hyperplasia can be difficult. Integration of all available information, including the clinical setting, is crucial to arriving at the appropriate diagnosis. In this review, we cover the diagnostic approaches to primary cutaneous marginal zone lymphoma, primary cutaneous follicle center lymphoma, and PCDLBCL-LT, and discuss their differential diagnosis.
A re-examination of atmospheric sulfuric acid aerosol formation and growth

Abstract Atmospheric sulfuric acid aerosol formation and growth is re-examined using the Middleton-Kiang kinetic aerosol model revised to include new information on aerosol nucleation and coagulation rates. The recent modifications in the coagulation rate coefficient are shown to have little effect on our previous analysis of aerosol growth process. Use of the new sulfuric acid vapor pressure data, which is higher than previously assumed, leads to an increase in the nucleation rates. As a result, secondary aerosol formation in the presence of pre-existing particles is enhanced. In addition, growth of these tiny new particles into the submicron particle size range which contribute to adverse effects such as visibility degradation becomes even more pronounced.
The effects of thermal history on the structure/property relationship in polyphenylenesulfide/carbon fiber composites

The purpose of this investigation was to examine the effects of thermal history during cooling from the melt on the degree of crystallinity, morphology, and mechanical properties of polyphenylenesulfide (PPS)/carbon fiber composites. Three thermal treatments were employed in this study: isothermal crystallization from the melt at 140, 160, 180, 200, and 220 C; quenching from 315 C and then annealing at 160 and 200 C; and nonisothermal crystallization from the melt at rates varying from 0.4 C/min to 68 C/s. The effect of varying the thermal history of the sample on the degree of crystallinity developed in the matrix polymer was determined using DSC. The effect of thermal history on and the resulting matrix morphology was examined by SEM. The subsequent effects of the degree of crystallinity and the morphology on the mechanical behavior of the samples were monitored by transverse tensile tests and flexural tests. In all cases, the transverse tensile and flexural moduli increased as the amount of crystallinity in the samples increased. However, samples with greater amounts of crystallinity did not always yield higher transverse tensile or flexural strengths. Upon examination of the composite samples by electron microscopy, it was observed that large increases in the valuesmore » of the transverse tensile and flexural strengths could be correlated with structural changes in the matrix. 25 refs.« less
ROEDDERITE IN THE QINGZHEN (EH3) CHONDRITE

The rare mineral roedderite, (Na1.09 K0.89 Ca0.02)2.00 (Mg4.71 Fe0.27)4.98 (Si11.80 Al0.09)11.89 O30 has been found in accessory amounts in the highly unequilibrated enstatite chondrite, Qingzhen. It occurs in association with minor amounts of albite and SiO2 as inclusions within the metal or sulfide phases of metal-sulfide assemblages. The roedderite crystals are connected through oxide and silicate veins to the surrounding matrix. The presence of glass coated vesicles on the surface of the assemblages strongly suggests that roedderite originated in the presence of a fluid phase, presumably during post-accretional planetary processes.