cssi/SciSciGPT-SciSciNet huggingface dataset:
Classical Hodgkin Lymphoma of cystic thymus in a patient with infectious mononucleosis: Diagnostic challenges and practical considerations

Abstract Establishing the diagnosis of classical Hodgkin lymphoma (cHL) in a timely fashion can be a challenge, as there are no pathognomonic signs or symptoms. The percutaneous needle biopsy (CNB) of the tumor gained increased popularity due to its minimal invasiveness and expeditious recovery from procedure. The diagnostic accuracy of CNB depends upon patient size, mass accessibility, and feasibility to obtain diagnostic tissue assuming that the tumor is histologically homogenous. We report on a patient with cHL who underwent multiple CNB from different sites before the diagnosis was established. Yet, only the incisional biopsy of the most metabolically-active tumor site resulted in diagnostic success. It is imperative to thoroughly consider both the biopsy method and the biopsy site for establishing correct diagnosis.
β-Methyl-δ-valerolactone-containing Thermoplastic Poly(ester-amide)s: Synthesis, Mechanical Properties, and Degradation Behavior.

Poly(ester-amide)s (PEAs) have been prepared from (glucose-derived) β-methyl-δ-valerolactone (MVL) by reaction of MVL-derived diamidodiols with diacid chlorides in solution to form poly(ester-amide)s having alternating diester-diamide subunits. The PEAs formed by this method exhibit plastic properties and are of sufficiently high molecular weight to be tough, ductile materials (stress at break: 41–53 MPa, strain at break: 530–640%). The length of the methylene linker unit (n = 1,2,3) between amide groups of the diamidodiols affects the Young's modulus; longer linkers reduce the stiffness of the materials. This allows tuning of the properties by judicious choice of precursors. MVL was also converted to a diacid chloride that was then used to prepare a PEA that is 76 wt% MVL-derived. The degradation rates of suspensions of these new PEAs in basic aqueous media were benchmarked and their instability in aqueous acid was also observed. NMR studies were used to detect the hydrolytic degradation products of both these PEAs as well as a structurally simpler analog.
Social status differences in allostatic load among young adults in the United States.

Allostatic load refers to wear and tear on the body due to repeated activation of the stress response and, thus, may be an early subclinical indicator of future disease and mortality risk. To date, few studies of allostatic load have focused on young adults, racial/ethnic comparisons that include Mexican Americans, or the interplay between race/ethnicity, gender, and educational attainment. To fill these gaps, we used data on non-Hispanic Black, non-Hispanic White, and Mexican-origin respondents from Waves I (1994-1995) and IV (2007-2008) of the National Longitudinal Study of Adolescent to Adult Health (Add Health; N = 11,807). We calculated allostatic load scores based on respondents' values for 10 metabolic, cardiovascular, and inflammatory biomarkers measured at Wave IV, when respondents were 24-34 years old. We then used negative binomial regression models to assess the combined effects of race/ethnicity, gender, and educational attainment on allostatic load, while controlling for key covariates. We found that Black women had significantly higher allostatic load scores than White women and Black men, net of educational attainment and other covariates. Yet, education modified the relationship between race/ethnicity, gender, and allostatic load. Obtaining a college education was protective for White males and females but no more or less protective for other women and deleterious for Black males. In other words, by the time they reach young adulthood, the cumulative physiological burden of stress on Black women and college-educated Black men is already greater than it is among their similarly or less educated White counterparts. These findings provide important information about the intermediate physiological dysregulation that underlies social inequalities in stress-related health outcomes, especially those that occur at the intersections of race/ethnicity, gender, and educational attainment. They also suggest that research on its antecedents should focus on earlier life periods.
An Integrated 2D Ultrasound Phased Array Transmitter in CMOS With Pixel Pitch-Matched Beamforming

Emerging non-imaging ultrasound applications, such as ultrasonic wireless power delivery to implantable devices and ultrasound neuromodulation, require wearable form factors, millisecond-range pulse durations and focal spot diameters approaching 100 μm with electronic control of its three-dimensional location. None of these are compatible with typical handheld linear array ultrasound imaging probes. In this work, we present a 4 mm × 5 mm 2D ultrasound phased array transmitter with integrated piezoelectric ultrasound transducers on complementary metal-oxide-semiconductor (CMOS) integrated circuits, featuring pixel-level pitch-matched transmit beamforming circuits which support arbitrary pulse duration. Our direct integration method enabled up to 10 MHz ultrasound arrays in a patch form-factor, leading to focal spot diameter of ∼200 μm, while pixel pitch-matched beamforming allowed for precise three-dimensional positioning of the ultrasound focal spot. Our device has the potential to provide a high-spatial resolution and wearable interface to both powering of highly-miniaturized implantable devices and ultrasound neuromodulation.
Unit-Weight Laplacians are Complete for Linear Systems Modulo $p$

In this paper, we prove that over the finite field $\mathbb{Z}_p$, solving unit-weight Laplacian linear systems is as hard as solving general linear systems. The proof includes the following two reductions. (1) Reduce solving a general linear system $\mathbf{A}$ to solving a weighted Laplacian system $\mathbf{L}$ of size $O(\mathrm{nnz}(\mathbf{A}))$. (2) Reduce solving a weighted Laplacian system $\mathbf{L}$ to solving a unit-weight Laplacian system $\bar{\mathbf{L}}$ of size $O\left(\mathrm{nnz}(\mathbf{L})\log^2p/\log\log p\right)$.
Astrocytic ApoE underlies maturation of hippocampal neurons and cognitive recovery after traumatic brain injury in mice

Polymorphisms in the apolipoprotein E (ApoE) gene confer a major genetic risk for the development of late-onset Alzheimer's disease (AD) and are predictive of outcome following traumatic brain injury (TBI). Alterations in adult hippocampal neurogenesis have long been associated with both the development of AD and recovery following TBI and ApoE is known to play a role in this process. In order to determine how ApoE might influence hippocampal injury-induced neurogenesis, we generated a conditional knockout system whereby functional ApoE from astrocytes was ablated prior to injury. While successfully ablating ApoE just prior to TBI in mice, we observed an attenuation in the development of the spines in the newborn neurons. Intriguingly, animals with a double-hit, i.e. injury and ApoE conditionally inactivated in astrocytes, demonstrated the most pronounced impairments in the hippocampal-dependent Morris water maze test, failing to exhibit spatial memory after both acquisition and reversal training trials. In comparison, conditional knockout mice without injury displayed impairments but only in the reversal phase of the test, suggesting accumulative effects of astrocytic ApoE deficiency and traumatic brain injury on AD-like phenotypes. Together, these findings demonstrate that astrocytic ApoE is required for functional injury-induced neurogenesis following traumatic brain injury.
A two-level multicast routing strategy for delay tolerant networks

Delay Tolerant Networks (DTNs) are sparse mobile ad-hoc networks in which there is typically no complete path between the source and destination. Multicast is an important group communication paradigm that is required by many potential DTN applications, such as data dissemination during military and rescue operations. While multicasting has been studied extensively in the context of the Internet and Mobile Ad-Hoc Networks (MANETs), efficient multicasting in DTNs is a significantly different and challenging problem due to frequent partitions and intermittent connectivity among nodes. In this paper, we propose a two-level single-copy multicast routing strategy that optimizes both the computing resource usage and the delivery rate. Furthermore, our scheme minimizes the transmission cost by bundling multiple multicast receivers into a single copy of the data packet, and forwarding it to an encounter node that has high delivery probabilities to those multicast receivers. This dynamic tree branching technique allows routing paths to be efficiently shared among multicast destinations. Lastly, we propose new methods to compute one-hop and multihop delivery probabilities that are used in forwarder selection. Through extensive simulation studies using a real-world mobility trace, we show that our scheme achieves a high delivery ratio, low delay, and low (or comparable) transmission cost compared to other multicast strategies.
The Main Sequence Evolution of Rotation and Chromospheric Activity in Solar-Type Stars

The behavior of rotation and chromospheric emission is outlined for solar-type stars. From about 1.2 M ⊙ down to 0.8 M⊙, rotation appears to obey a power-law relationship with age: Ω ∝ t –1/2. This relation can be derived from simple models of angular momentum loss. For stars more massive than the Sun, there is a sharp decline of Ω with mass at any age, but this levels out for stars less massive than the Sun. The most rapidly rotating solar-type stars rotate at about 10 times the solar rate, and the slowest at about half the solar rate.
Generalized accumulation of neutral glycosphingolipids with GM2 ganglioside accumulation in the brain

Analyses have been made of glycosphingolipids from visceral organs and brain of a patient with an unusual lipid storage disorder diagnosed initially as classical Tay-Sachs disease. Levels of the lipids from fresh-frozen sections of gray and white matter, kidney, spleen, liver, and heart from this patient were compared with those of normal juvenile controls, and the fatty acid composition of accumulated glycosphingolipids was compared with reference compounds. This patient was found to have abnormally high concentrations of a globoside in liver, kidney, and spleen, asialo GM2 ganglioside in brain and liver, and GM2 ganglioside in the brain. On the basis of these findings along with the clinical manifestations of Tay-Sachs disease with visceral involvement (hepatosplenomegaly) and demonstration of total deficiency of both A and B components of β-N-acetylhexosaminidase activity, this glycosphingolipidosis is the same as two previously reported cases of GM2 gangliosidosis with globoside accumulation and total β-N-acetylhexosaminidase deficiency.
Predicting medical school and internship success: does the quality of the research and clinical experience matter?

ABSTRACT Objectives: This article explores specific aspects of self-reported clinical and research experience and their relationship to performance in medical training. Methods: This is a retrospective cohort study conducted at the Uniformed Services University. The American Medical College Application Service application was used to discern students' self-reported clinical and research experience. Two authors applied a classification scheme for clinical and research experience to the self-reported experiences. Study outcomes included medical school grade point average (GPA), U.S. Medical Licensing Examination (USMLE) scores, and intern expertise and professionalism scores. A linear regression analysis was conducted for each outcome while controlling for prematriculation GPA. Results: Data were retrieved on 1,020 matriculants. There were several statistically significant but small differences across outcomes when comparing the various categories of clinical experience with no clinical experience. The tech...
Instructional Sensitivity as a Psychometric Property of Assessments

Standards-based reform, as codified by the No Child Left Behind Act, relies on the ability of assessments to accurately reflect the learning that takes place in U.S. classrooms. However, this property of assessments—their instructional sensitivity—is rarely, if ever, investigated by test developers, states, or researchers. In this paper, the literature on the psychometric property of instructional sensitivity is reviewed. Three categories of instructional sensitivity measures are identified—those relying on item or test scores only, those relying on item or test scores and teacher reports of instruction, and strictly judgmental methods. Each method identified in the literature is discussed alongside the evidence for its utility. Finally, recommendations are made as to the proper role of instructional sensitivity in the evaluation of assessments used under standards-based reform.
The Role of Genotypes That Modify the Toxicity of Chemical Mutagens in the Risk for Myeloproliferative Neoplasms

Background: The etiology of myeloproliferative neoplasms (MPN) (polycythemia vera; essential thrombocythemia; primary myelofibrosis) is unknown, however they are associated with a somatic mutation—JAK2 V617F—suggesting a potential role for environmental mutagens. Methods: We conducted a population-based case-control study in three rural Pennsylvania counties of persons born 1921–1968 and residing in the area between 2000–2008. Twenty seven MPN cases and 292 controls were recruited through random digit dialing. Subjects were genotyped and odds ratios estimated for a select set of polymorphisms in environmentally sensitive genes that might implicate specific environmental mutagens if found to be associated with a disease. Results: The presence of NAT2 slow acetylator genotype, and CYP1A2, GSTA1, and GSTM3 variants were associated with an average 3–5 fold increased risk. Conclusions: Exposures, such as to aromatic compounds, whose toxicity is modified by genotypes associated with outcome in our analysis may play a role in the environmental etiology of MPNs.
Culinary Skills and Their Importance to Practicing Dietitians

Abstract Knowledge of food plays an important role in all areas of dietetics. The American Dietetic Association recently updated standards of practice to require that entry level dietitians have basic knowledge of culinary skills. However, there is limited researcn on the culinary or food skills needed by dietitians. This purpose of this research was to determine the basic culinary skills important to practicing dietitians. A convenience sample of 83 Registered Dietitians who attended the national meeting completed the survey.Of the respondents, 31% had food management responsibilities. The respondents rated 26 basic culinary skills on a 5-point Likert scale from 1 very unimportant to 5 very important. The highest rated skills were handling food safely (4.17), making food substitutions for special diets (4.11), and developing menus (4.02). The lowest rated skills included understanding leavening systems (2.20) and preparing yeast breads (1.98). When comparing dietitians with food management responsibilities to those without, there were significant differences (p≥.05) for 15 of the 26 skills. Those which were not significantly different were knowledge of international cuisines, making substitutions for special diets, and using common food substitutes. In today's dietetic practice, many "nutrition" experts have tried to separate themselves from food. These findings support the American Dietetic Association and its Standards of Practice because they indicate that culinary skills are a key competency for practicing dietitians.
Approach to the treatment of hypertension in older patients: Preliminary results with isradipine

Abstract The risks of hypertension in the elderly, including increased morbidity and mortality rates from stroke, congestive heart failure, coronary heart disease, peripheral vascular disease, and maculopathy, are well documented. Although treatment of combined systolic and diastolic hypertension in older patients has been shown to be effective in decreasing morbidity and mortality rates and is associated with a low risk of adverse effects, many physicians remain reluctant to treat the elderly. There is substantial interest in the potential value of calcium channel blockers as monotherapy in elderly hypertensive patients. This article reports the preliminary results from a study comparing titrated doses of 25 to 75 mg per day hydrochlorothiazide with titrated doses of 5 to 15 mg per day of a new calcium channel blocker, isradipine, in hypertensive persons 65 years and older.
Characterization of random copolymers by size exclusion chromatography with a light scattering detector

Abstract Measurement of the molecular weight and molecular-weight distribution of copolymers by size exclusion chromatography (s.e.c.) can be difficult because of the lack of appropriate samples for calibration of the column. Comparison of copolymers of varying composition is even more problematic. The recent development of light scattering detectors for s.e.c. permits direct measurement of the molecular weight as the polymer elutes from the column, so that no calibration is necessary. A series of six copolymers of poly(4-(acetoxymethyl)styrene- co -4-(t-butyloxycarbonyloxy)styrene) have been measured, ranging in composition from 5 to 100 mol% of the poly(4-(acetoxymethyl)styrene). The differential refractive index increment varied linearly with composition. The weight-average molecular weights ( M w ) determined by s.e.c. with the light scattering detector agree well with those determined with light scattering alone. Application of the technique to copolymers is discussed.
The Role of Markets, Technology, and Policy in Generating Palm-Oil Demand in Indonesia

Indonesia produces more palm oil and consumes more palm oil per capita than any country in the world. This paper examines the processes through which Indonesia has promoted palm oil consumption and some of the consequences of that transformation. Partial equilibrium modeling shows that Indonesia’s remarkable increase in palm oil consumption since 1985 is not largely attributable to population and income growth. Instead, much of Indonesia’s palm oil consumption growth results from substitution away from coconut oil, a process that was facilitated by government policies around technology, pricing, distribution, and trade. The switch from coconut oil to palm oil in Indonesia was associated with increased land conversions to agriculture and diminished smallholder competitiveness. Despite lower rates of cooking oil substitution in the future, simulations suggest that Indonesia’s total palm oil consumption in 2035 will be at least double that of 2010.
Computer simulation of displacement spike annealing

Abstract A computer simulation of short term annealing of 5- and 20-keV displacement cascades in α-iron has been carried out. A Monte Carlo technique was used to move the defects in correlated random walks on a bcc lattice. Correlations extended to 10th neighbors for interstitials and 5th neighbors for vacancies. A low temperature simulation permitted only interstitial migration, whereas a high temperature simulation permitted both interstitial and vacancy migration with a jump frequency ratio of 100 to 1. Temperature sensitive parameters included the jump frequency of the di-interstitial relative to the single interstitial and the recombination region for unlike defects. Annihilation amounted to 80 per cent and 50 per cent at high and low temperature, respectively. Relative to the low temperature anneal, the high temperature anneal resulted in about the same number of vacancy clusters (although the production of large clusters was clearly enhanced) and only one-third as many interstitial clusters. A deta...
Visual processing in amblyopia: human studies.

Within the last five years, there have been a number of exciting new advances in our knowledge and understanding of amblyopia. This article reviews recent psychophysical studies of naturally occurring amblyopia in humans. These studies suggest that: 1) There are significant differences in the patterns of visual loss among the clinically defined categories of amblyopes. A key factor in determining the nature of the loss is the presence or absence of binocularity. 2) Dysfunction within the amblyopic visual system first occurs in area V1, and the effects of amblyopia may be amplified downstream. 3) There appears to be substantial neural plasticity in the amblyopic brain beyond the “critical period.”
Numerical quadrature computation of the macdonald function for complex orders

The use of Gaussian quadrature formulae is explored for the computation of the Macdonald function (modified Bessel function) of complex orders and positive arguments. It is shown that for arguments larger than one, Gaussian quadrature applied to the integral representation of this function is a viable approach, provided the (nonclassical) weight function is suitably chosen. In combination with Gauss–Legendre quadrature the approach works also for arguments smaller than one. For very small arguments, power series can be used. A Matlab routine is provided that implements this approach.
Understanding the differences in film formation mechanisms of two comparable solvent based and water-borne coatings on bronze substrates by electrochemical impedance spectroscopy

Abstract Corrosion protection of bronze, a metal alloy which is commonly used in decorative architectural elements and for statuary, is a challenge particularly as new and previously untested water-borne coatings are supplanting traditionally used solvent based polymers as protective coatings. Studying film formation of coatings to better prevent corrosion of culturally significant works is an important problem in the field of conservation science. This work aims to further understanding of differences between films formed from water-borne lattices versus solvent based polymeric coatings on bronze substrates using electrochemical impedance spectroscopy and gravimetric analysis to investigate the changes of coatings as they formed solid films. Using equivalent electric circuit models, electrochemical snapshots of the developing films were produced. Those models established time points for the transitions between theoretical stages of the nascent films and allowed for a comparison between two major classes of coating types (using the water-borne Rhoplex™ WL-81 and the solvent based Paraloid™ B-44). Electrochemical analysis showed that diffusion occurs during early stages of film formation of both coating types. The prolonged coalescence of coatings produced from the water-borne latex was found to leave those films susceptible to water sorption. Annealing films as a means to drive out remaining hydrophilic additives and to facilitate film formation was investigated.
Galantide distinguishes putative subtypes of galanin receptors in mudpuppy parasympathetic neurons

Abstract The effect of the chimeric ligand galantide on the galanin-induced activation of membrane K+ conductance and inhibition of voltage-dependent Ca2+ conductance has been studied using voltage-clamped dissociated mudpuppy parasympathetic neurons. Galantide did not activate the K+ conductance but produced a concentration-dependent antagonism (IC50 = 4 nM) of the galanin-induced increase in K+ conductance. Galantide acted like galanin and inhibited the voltage-dependent Ba2+ current (IBa). The inhibition of IBa also was concentration dependent (IC50 = 16 nM) and the maximum inhibition produced by galantide was approximately 40%. We also demonstrate that the galanin-(1–16) fragment increased the membrane K+ conductance and decreased IBa, suggesting that the NH2 portion of the galanin molecule is sufficient to mediate both actions. One interpretation of these observations is that different galanin receptors mediate the different effects of galanin on the mudpuppy parasympathetic neurons.
High speed all-optical PRBS generation based on quantum-dot semiconductor optical amplifiers

A scheme to generate return-to-zero on-off keying (RZ-OOK) high speed all-optical pseudo random bit sequence (PRBS) based on quantum-dot semiconductor optical amplifiers (QD SOA) has been studied. By analyzing the performance of the core functional unit of this system, which is composed of QD SOA-based logic XOR and AND gates, as well as considering the saturation effect of the QD device and noise level of the system, we demonstrated the system's capability of producing stable high speed optical PRBS signals. Results show that the performance of the system depends on a number of parameters, including relaxation lifetime from QD excited state to ground state, injected current density, bit repetition rate, signal pulse width and single pulse energy. For devices with relaxation time approximately 1.0 ps, injected current density >1.8 kA/cm(2), single pulse energy <1.0 pJ with pulse width around 1.0 ps, the system is capable of PRBS generation at speeds of approximately 250 Gb/s.
Antimicrobial Stewardship—the State of the Art in 2011: Focus on Outcome and Methods

Antimicrobial stewardship programs attempt to optimize prescribing of these drugs to benefit both current and future patients. Recent regulatory and other incentives have led to widespread adoption of such programs. Measurements of the success of these programs have focused primarily on process measures. However, evaluation of outcome measures will be needed to ensure sustainability of these efforts. Outcome efforts to date provide some evidence for improved care of individual patients, some evidence for minimizing emergence of resistance, and ample evidence for cost reduction. Attention to evaluation methods must be increased to provide convincing evidence for the continuation of such programs.
Excited State Relaxation Dynamics of the Zinc(II) Tetraphenylporphine Cation Radical

A new technique employed to study the photophysical properties of the zinc(II) tetraphenylporphine cation radical is reported. It employs a combination of controlled potential coulometry and femtosecond absorption spectrometry. The fast transient lifetime of 17 ps of the pi-cation species originates in very efficient mixing of the a(2u) HOMO cation orbital that places electronic density mainly on pyrrolic nitrogens and metal d-orbitals. That explains the lack of any emission of the cationic species. This nonradiative decay process might elucidate the processes taking place in photosynthetic systems when an electron is removed from the porphyrinic moiety and the hole is produced.
Combined Open and Endovascular Repair for Aortic Arch Pathology

Background and Objectives We describe our experience with combined open and endovascular repair in patients who have aortic arch pathology.
Three-dimensional structure of a low-Reynolds-number turbulent boundary layer

A low-Reynolds-number zero-pressure-gradient incompressible turbulent boundary layer was investigated using a volumetric imaging technique. The Reynolds number based on momentum thickness was 700. The flow was tagged with a passive scalar from two spanwise dye slots to distinguish between fluid motions originating in the inner and outer portions of the boundary layer. The resulting volumetric scalar field was interrogated using a laser sheet scanner developed for this study. Twoand three-dimensional time-dependent visualizations of a 50 volume time series are presented (equivalent to 17δ in length). In the outer portion of the boundary layer, scalar structures were observed to lie along lines in the (x, z)-plane, inclined to the streamwise (x-)direction in the range ±50 ◦ . The ejection of brightly dyed fluid packets from the near-wall region was observed to be spatially organized, and related to the passage of the large-scale scalar structures.
Vessel-Based Education Programs in the Great Lakes: An Evaluation of Effects on Student Knowledge and Attitudes

Abstract Vessel-based education programs are found throughout the Great Lakes region, yet they have received little quantitative evaluation attention. The focus of this research was to measure the impacts of one such multi-disciplinary program, the Great Lakes Education Program (GLEP), on changes in Great Lakes knowledge and attitudes of fourth grade students. A valid and reliable written survey was developed from eight pre-existing instruments. The study incorporated a quasi-experimental, pre- and post-test design involving 39 fourth grade classrooms (945 students). As a result of the GLEP vessel experience, students exhibited a highly significant increase in Great Lakes knowledge, and girls experienced a statistically significant increase in positive attitudes toward the Great Lakes. Boys had significantly more Great Lakes and aquatic experiences than girls. Recommendations for vessel-based education programs include conducting rigorous evaluations with reliable and valid measurements for knowledge and attitudes, using research designs with controls for threats to validity, conducting longerterm follow-up evaluations with students, and strengthening cruise and classroom curricula.
Nutritional and disease stress of juveniles from the Dakhleh Oasis, Egypt

Bioarchaeologists use skeletal health indicators to measure how ancient populations adapted to their physical, cultural and biological environments. Skeletons of infants and children are rarely included in these kinds of analyses because of factors such as poor preservation, small sample size, incomplete recovery or research design. In this study, skeletal remains of juveniles aged from foetal to 15 years (N = 238) from Kellis 2, a Romano-Byzantine cemetery in the Dakhleh Oasis, Egypt, are analysed to shed light on how infants and children were affected by Roman policies during the early years of the Christianisation of Egypt. Non-specific indicators of physiological stress (cribra orbitalia, enamel hypoplasia and osteoperiostitis) are analysed for post-natal individuals and interpreted in the context of the physical, cultural and biological landscapes. Results from these analyses suggest moderate levels of skeletal and dental stress with a marked improvement in general health from pre-Roman times. This study contributes to a better understanding of juvenile paleoepidemiology and mortuary practices in Egypt during the Romano-Byzantine period. Copyright © 2010 John Wiley & Sons, Ltd.
Linguistic register of foreign language instruction

In an attempt to establish systematic characteristics and patterning of the language variety used by foreign language teachers in talking to their students, an experiment was designed to isolate significant features of this linguistic register from the speech of eight native speakers of Czech addressing a group of Stanford students who were studying Czech as a foreign language. It was found that a Foreign Language Classroom Register is a linguistic subsystem that can be defined (1) by rules of linguistic simplification similar to those of the Foreigner Talk and Baby Talk Registers, and (2) by constraints imposed by the social setting, which is the norm of the standard language used in a classroom communication.
Effects of increased suspended sediment on growth rate and gill condition of two southern Appalachian minnows

Despite the recognition that increased suspended sediment concentration (SSC) is a correlate of imperilment for native riverine fishes, research is limited on the effects of SSC on small non-game species. This study quantifies the impact of suspended sediment on fish growth and gill condition of two stream-dwelling minnows. Specific growth rate (i.e., percent change in mass per day) and gill condition (i.e., lamellar thickness and interlamellar area) were measured in young-of-year whitetail shiners, Cyprinella galactura, and federally threatened spotfin chubs, Erimonax monachus, exposed for 21 days to increased SSC (0, 25, 50, 100, and 500 mg L−1). Exposure to elevated SSC caused a significant decrease in specific growth rate in both species and at all life stages tested. The effect of increased SSC was greatest in spotfin chubs, which exhibited a 15-fold decrease in specific growth rate at the highest treatment (500 mg L−1). Effects of increased SSC were least for 8–9-month-old whitetail shiners, which had growth rates similar to controls for 25, 50, and 100 mg L−1 treatments. These minnows exhibited a greater response to increasing SSC than salmonids at low to moderate SSC, and a lesser response at higher sediment levels. Gill damage was minimal at the three lowest treatment levels, moderate at 100 mg L−1 and severe at 500 mg L−1, indicating that respiratory surfaces of upland minnows may be much more sensitive than other species. Specific growth rate decreased significantly with increasing gill lamellar thickness, suggesting that respiratory impairment is one mechanism responsible for negative impacts of excessive sediment on small riverine fishes.
High temperatures in inertial confinement fusion radiation cavities heated with 0.35 microm light.

We have demonstrated efficient coupling of 0.35 $\ensuremath{\mu}\mathrm{m}$ laser light for radiation production in inertial confinement fusion (ICF) cavity targets. Temperatures of 270 eV are measured in cavities used for implosions and 300 eV in smaller cavities, significantly extending the temperature range attained in the laboratory to those required for high-gain indirect drive ICF. High-contrast, shaped drive pulses required for implosion experiments have also been demonstrated for the first time. Low levels of scattered light and fast electrons are observed, indicating that plasma instability production is not significant.
DLG1 is an anchor for the E3 ligase MARCH2 at sites of cell–cell contact

PDZ domain containing molecular scaffolds plays a central role in organizing synaptic junctions. Observations in Drosophila and mammalian cells have implicated that ubiquitination and endosomal trafficking, of molecular scaffolds are critical to the development and maintenance of cell-cell junctions and cell polarity. To elucidate if there is a connection between these pathways, we applied an integrative genomic strategy, which combined comparative genomics and proteomics with cell biological assays. Given the importance of ubiquitin in regulating endocytic processes, we first identified the subset of E3 ligases with conserved PDZ binding motifs. Among this subset, the MARCH family ubiquitin ligases account for the largest family and MARCH2 has been previously implicated in endosomal trafficking. Next, we tested in an unbiased fashion, if MARCH2 binds PDZ proteins in vivo using a modified tandem affinity purification strategy followed by mass spectrometry. Of note, DLG1 was co-purified from MARCH2, with subsequent confirmation that MARCH2 interacts with full-length DLG1 in a PDZ domain dependent manner. Furthermore, we demonstrated that MARCH2 co-localized with DLG1 at sites of cell-cell contact. In addition, loss of the MARCH2 PDZ binding motif led to loss of MARCH2 localization at cell-cell contact sites and MARCH2 appeared to localize away from cell-cell junctions. In in vivo ubiquitination assays we show that MARCH2 promotes DLG1 ubiquitination. Overall, these results suggest that PDZ ligands with E3 ligase activity may link PDZ domain containing tumor suppressors to endocytic pathways and cell polarity determination.
Fast computation of the Euclidian distance maps for binary images: Fast computations of the Euclidean distance maps for binary images

Abstract A simple algorithm is given for the computation of the Euclidian distance from the set of black points in an N × N black and white image, for all points in the image. The running time is O(N2 log N) and O(N) extra space is required. The algorithm is suitable for implementation on a parallel machine.
Models of acute myeloid leukemia: Prospects for drug development and testing

Acute myeloid leukemia (AML) is a common and deadly form of leukemia. New therapies are desperately needed. The availability of appropriate disease model systems is crucial to development of effective treatment. A significant progress in generating and characterizing such model systems has been made in the past decade. Here, the relative benefits of cell lines, transgenic mice and xenografted primary AML model will be compared, along with speculation on new models suitable for AML drug discovery.
La caja negra de la teoría del haz: desafíos explicativos para la teoría de la sustancia como haz de propiedades

En este articulo me propongo contribuir al proyecto mas amplio de evaluar los meritos relativos de las distintas teorias de la sustancia. Un paso preliminar importante en este proyecto consiste en evaluar los recursos explicativos de una de las principales teorias de la sustancia, la asi llamada teoria del haz. Este articulo pretende contribuir a tal evaluacion. Identifico y explico tres desafios explicativos diferentes que una teoria del haz adecuada debe responder. Cada uno apunta a una supuesta brecha explicativa, por lo que los llamo desafios explicativos. Considero tres estrategias para responder a estos desafios en el marco de la teoria del haz. Argumento que ninguna de ellas logra grandes avances. El resultado es que, a falta de otras estrategias para responder a los desafios, la teoria del haz requiere una cantidad significativa de estipulacion. Esta caja negra hace a la teoria del haz relativamente debil en lo que respecta a su poder explicativo —a menos que, por supuesto, las teorias rivales de la sustancia sean incapaces de hacer algo mejor—.
The structure of the acidic polysaccharide secreted by Rhizobium phaseoli strain 127 K38t

The acidic polysaccharide secreted by Rhizobium phaseoli strain 127 K36 was found to have a repeating unit of eight glycosyl residues and to contain two pyruvic acetal groups. Each of the glycosyl residues of the polysaccharide was determined to be in the d configuration and in the pyranoid ring-form. This repeating unit is, with the possible exception of base-labile substituents, identical with those found previously for the polysaccharides secreted by two strains of Rhizobium trifolii and two strains of Rhizobium leguminosarum, but different from the repeating unit of the polysaccharide secreted by Rhizobium phaseoli 127 K38. The octasaccharide repeating-unit of the Rhizobium phaseoli 127 K36 polysaccharide is shown on page 142.
Influence of alkaloid concentration on acceptability of tall larkspur (Delphinium spp.) to cattle and sheep.

Tall larkspur (Delphinium spp.) is a serious toxic plant problem on western U.S. ranges. The major toxins in tall larkspur are methyllycaconitine (MLA) and 14-deacetylnudicauline (14-DAN); the sum of both is termed the toxic alkaloid concentration. Toxic alkaloids comprise about 20–50% of the total alkaloid concentration in tall larkspur. Toxic and total alkaloid concentration generally declines with maturity, whereas cattle and sheep consumption of larkspur typically increases with plant maturity. We hypothesized that cattle and sheep consumption of tall larkspur was negatively related to higher concentrations of total or toxic alkaloid. We compared consumption of several collections of dried, ground larkspur and fresh larkspur in a series of trials. In another trial, a crude alkaloid fraction was extracted with ethanol, added to alfalfa hay, and consumption compared to untreated alfalfa hay, alcohol-treated hay, and the essentially alkaloid-free plant residue. In all cases we correlated amounts eaten with total and toxic alkaloid concentration. A grazing trial was also conducted to relate larkspur consumption over time to alkaloid concentrations. Total alkaloid concentrations in dried, whole-plant collections ranged from 9.3 to 38.8 mg/g of dry weight, whereas toxic alkaloid concentrations varied from 0.0 to 7.1 mg/g. In one pen trial, cattle preferred a larkspur collection (P 0.05), however, between concentrations of total or toxic alkaloids and amount of dry plant consumed in this or any other trial. Conversely, sheep consumption tended to be negatively influenced by total and toxic alkaloid concentration (P≤0.08). In the trials with extract, cattle preferred the alcohol-treated hay and rejected the alkaloid-free residue (P 0.05) to alkaloid concentration. Cattle preferred leaves over flowers when offered individual plants differing in phenological stage and/or amount of shade, but alkaloid concentration was not related to consumption. We conclude that knowledge of the concentration of total or toxic alkaloid in tall larkspur will give little or no indication of plant acceptability to cattle. Even though accurate predictions can be made about the potential toxicity of larkspur based on the concentration of toxic alkaloids, predictions about consumption must be based primarily on plant phenology.
Thermomechanical response of a lead-free solder reinforced with a shape memory alloy

Abstract In order to improve solder joint life, we have experimented with a lead-free solder reinforced with a NiTi shape memory alloy (SMA). Concept viability was evaluated by conducting thermomechanical double-shear tests on bare SMA wire and single-fiber composites of Sn–3.5Ag matrix reinforced with a single SMA wire. A copper wire reinforced composite served as the control sample. The results indicate that a significant reduction in inelastic strain range can be realized by the SMA composite approach, suggesting a possible payoff in the life of solder joints.
Recent vertical crustal movement along the east coast of the United States

Abstract The first detailed profile of apparent vertical crustal movement along the east coast of the United States, extending from Calais, Maine to Key West, Florida, has been produced from the results of precise leveling by the National Geodetic Survey. Comparison of this profile with one obtained from secular trends in sea level reveals a serious systematic disagreement between the two methods, as large as 19 mm/year. Estimates of normal measurement error can account for some, but not all, of the misclosures indicated. Thus at least one of the methods must be seriously affected by some systematic non-tectonic influence. The cause of the discrepancy is presently unknown, but the comparisons presented here make possible an estimate of its magnitude, an important step toward identification of the cause and elimination of its effect. The two data sets have been adjusted using different assumptions as to the source of their disagreement to produce several possible versions of a crustal movement profile along the east coast. Comparison of these profiles with topography, gravity and seismicity indicate some weak correlations. However, there are several striking correspondences between apparent movements and tectonic and geomorphic features on a regional scale; in particular, the Connecticut Valley graben, the Chesapeake embayment, the Cape Fear arch and the Cape Canaveral prominence correspond to marked changes in the crustal movement profile. These correlations persist in all of the adjustments and it is unlikely that they can be attributed to chance. The implication is, therefore, that these four features are active elements in the contemporary tectonic fabric of the eastern United States.
Visual pigments of deep-sea fish.

EXPERIMENTS have been made on board R.V. Sarsia with the fresh retinae of four species of deep-sea fish caught in the Bay of Biscay. These species, Stomias boa (Risso), Flagellostomias sp., Argyropelecus olfersii (Cuvier) and Myctophum punctatum Rafinesque, are often caught around 500 m.1, a depth close to that at which the human eye ceases to see the light of day2.
A Hierarchical key management Scheme for End-to-End Encryption in Internet Environments

The problem of designing key management schemes for establishing end-to-end encrypted sessions between source-destinationpairs when the source and the destination are on different networks interconnected via Gateways and intermediate networks is considered. In such an internet environment, the key management problem attains a high degree of complexity due to the differences in the key distribution mechanisms used in the constituent networks and the infeasibility of effecting extensive hardware and software changes to the existing networks. In this paper, a hierarchical approach for key management is presented which utilizes the existing network specific protocols at the lower levels and protocols between Authentication Servers and/or Control Centers of different networks at the higher levels. Details of this approach are discussed for specific illustrative scenarios to demonstrate the implementational simplicity. A formal verification of the security of the resulting system is also conducted by an automatic procedure utilizing certain combinatory logic principles. This approach is general and can be used for verifying the security of any existing key management scheme.
Influences on peer evaluation in a group project: an exploration of leadership, demographics and course performance

Collaborative learning strategies are widely used in higher education to deepen learning, promote team-building skills and achieve course learning objectives. Using peer evaluation is an important strategy to ensure that engaged and active students are rewarded for their efforts, and to discourage loafing within groups. However, less is known about what biases may influence students’ peer evaluations. In this paper, we investigate what variables students may (consciously or unconsciously) use to evaluate their peers. We explore the role of sex, race, course performance and group leadership on peer evaluation. We also investigate whether these variables correlate with students’ final course grade. We found that students who reported being leaders in groups were evaluated higher than peers who reported being followers, and that course performance positively correlated with peer evaluations. White students received higher peer evaluations than students of colour. This difference reflects trends in group lead...
Comparing preference assessments: Selection- versus duration-based preference assessment procedures

In the current investigation, the results of a selection- and a duration-based preference assessment procedure were compared. A Multiple Stimulus With Replacement (MSW) preference assessment [Windsor, J., Piche, L. M., & Locke, P. A. (1994). Preference testing: A comparison of two presentation methods. Research in Developmental Disabilities, 15, 439-455] and a variation of a Free-Operant (FO) preference assessment procedure [Roane, H. S., Vollmer, T. R., Ringdahl, J. E., & Marcus, B. A. (1998). Evaluation of a brief stimulus preference assessment. Journal of Applied Behavior Analysis, 31, 605-620] were conducted with four participants. A reinforcer assessment was conducted to determine which preference assessment procedure identified the item that produced the highest rates of responding. The items identified as most highly preferred were different across preference assessment procedures for all participants. Results of the reinforcer assessment showed that the MSW identified the item that functioned as the most effective reinforcer for two participants.
The Existence of Reasonable Doubt as to Revenue Collection and Expense Payment: Implications for Accrual Basis Taxpayers

One of the basic assumptions of accrual accounting is that, in due time, revenue earned in the normal course of business will be collected and liabilities incurred will be paid. Yet, case law indicates that it is inappropriate to impose the income tax on amounts whose collection is reasonably in doubt, even though these amounts are fixed, determinable, and undeniably due the taxpayer. In such an event, taxpayers can either exclude the income item from gross income, viz., the common law doubtful collection exception, or include the item in gross income and charge bad debt expense upon specifically writing off the matching receivable. While the common law doubtful collection exception is conceptually sanctioned by the tax court and the Federal Circuits, conflict exists concerning the level of financial distress required to establish reasonable doubt and the exact point in time when such distress must exist. More important, given that the common law doubtful collection exception is independent of the highly ...