cssi/SciSciGPT-SciSciNet huggingface dataset:
The Variable Threshold Rod Experiment: A Comparison of Measured and Computed Deformations

By appropriate prior cold working of stock material and fabrication of test specimens with tailored dimensions, the location of the deformation zones along the gage length of tensile specimens was controlled. The experiment provides a sensitive test to judge the ability of constitutive models to replicate the behavior of metals undergoing inhomogeneous deformation. A comparison of experimental results with simulated response using an isotropic state variable model is presented
Solubilization and characterization of hormone- responsive phosphodiesterase activity of rat fat cells.

Abstract Fat cell particulate phosphodiesterase activity can be solubilized in high yield (80–100%) in a buffer system (30 mM Tris · HCl, pH 8.0) containing non-ionic detergents (0.1% Brij 30, 1.0% Triton X-100), salt (3.0 mM MgSO 4 , 5.0 mM NaBr) and dithiothreitol (5.0 mM). Polycrylamide gel electrophoresis of the solubilized enzyme activity indicated the presence of two bands of activities of different electrophoretic mobilities, both of which hydrolyzed cylic AMP and cyclic GMP. The solubilized activity eluted from DEAE Bio-Gel columns as a somewhat broad profile with at least two peaks of activity. Activity against both cyclic AMP and cyclic GMP eluted in similar but not identical patterns. The solubilized enzyme and DEAE column eluates exhibited low ( μ M) Michaelis constants for cyclic AMP and cyclic GMP. In addition, the increase in phosphodiesterase activity induced by incubation of intact fat cells with insulin or adrenocorticotropic hormone are maintained in the solubilized state.
Aortic Aneurysm Rupture Into a Retroaortic Left Renal Vein

We report the case of a patient who was transferred to our facility after a CT scan obtained at a local hospital revealed a leaking abdominal aortic aneurysm. Review of the scan showed an aorto-left renal vein fistula. Knowing this fistula was present made the operative repair of the aneurysm and control of the fistula much more straightforward than might otherwise have been the case. Although relatively rare, major anomalies of the renal veins and perirenal vena cava should be borne in mind when operating on the abdominal aorta. This case illustrates the merit of contrast-enhanced CT scanning prior to aortic surgery.
Acute Myocardial Infarction Attributable to Adrenergic Crises in a Patient with Pheochromocytoma and Neurofibromatosis 1

ABSTRACT Objective To describe a rare case of acute myocardial infarction in a patient with neurofibromatosis 1 and pheochromocytoma and to review the literature on the coexistence of these 2 diseases, the causes of myocardial injury in patients with pheochromocytoma, and the utility of genetic testing and pheochromocytoma screening for those patients and their families. Methods We present a case report, including the detailed clinical, laboratory, and radiographic data, results of adrenal mass pathology, and results of coronary angiography. We also survey other relevant reports available in the literature. Results A 43-year-old woman with a history of longstanding hypertension, neurofibromatosis 1, headaches, sweating, and palpitations presented to the hospital with chest pain and shortness of breath. She was found to have an acute myocardial infarction and pulmonary edema, as well as a right adrenal mass. A pheochromocytoma was suspected, and phenoxybenzamine was added to her treatment regimen. Cardiac catheterization showed nonobstructive coronary disease. The levels of plasma catecholamine metabolites were extremely high. The patient underwent uncomplicated laparoscopic right adrenalectomy 2 weeks after this admission. Surgical pathology confirmed the diagnosis of pheochromocytoma. Conclusion Adrenergic crisis attributable to pheochromocytoma can result in acute myocardial infarction even in the absence of obstructive coronary disease. Inclusion of pheochromocytoma in the differential diagnosis of hypertension in patients with neurofibromatosis is very important and helps avoid mistakes in the management of such patients. (Endocr Pract. 2007;13:269-273)
Analyzing the traumatic impact of childhood visual impairment.

Material is presented from three analyses involving the impact on adult functioning of childhood trauma to the visual system. The clinical process by which unrecognized but ongoing traumatic reactions are identified for subsequent analysis is described. It is of particular importance, with these patients, to recognize their lifelong experience of visual confusion resulting from problems in their visual anatomy. Only then can fantasies and affects related to these physically induced states of confusion be worked through. Working through these reactions promotes the neutralization of related primitive narcissistic affects, mourning, and realistic accommodation, and leads to a more intact and integrated sense of self, and a marked increase in self-esteem. With this newly integrated sense of self, the complex interaction between physically induced confusion states and more typical developmental conflicts with objects can be worked through, resulting in more realistic and intense cathexes of the external world. The trauma suffered by these patients had been greatly compounded by its having gone unrecognized. To miss this yet again in an analysis is to repeat the past and retraumatize the patient. These findings have clear implications for patients with other biologically related symptoms (e.g., ADD, ADHD, and dyslexia).
A two-level additive Schwarz preconditioner for nonconforming plate elements

A two-level additive Schwarz preconditioner is developed for the systems resulting from the discretizations of the plate bending problem by the Morley finite element, the Fraeijs de Veubeke finite element, the Zienkiewicz finite element and the Adini finite element. The condition numbers of the preconditioned systems are shown to be bounded independent of mesh sizes and the number of subdomains in the case of a generous overlap.
Independent measurements of force and position in atomic force microscopy

Historically, precise vertical control of an atomic force microscope (AFM) tip while it is disengaged from the surface has been an unsolved problem. By separately scattering a pair of lasers off the tip and a fiducial mark in the sample, we locally measured and thereby actively controlled tip and sample position in three dimensions, achieving atomic-scale (0.1 nm) precision at ambient conditions. We also measured cantilever deflection (force) using the standard optical-lever- arm geometry. Both detection techniques were used to determine the vertical location of the surface (z = 0) relative to the AFM tip assembly. The difference in these vertical determinations was 0.0 ± 0.3 nm (mean ± S.D.; N = 86). This agreement allowed us to establish an optically based reference frame to measure the vertical position of the tip relative to the surface. This reference frame is insensitive to long-term mechanical drift of the AFM assembly and complementary to the cantilever deflection sensing, which measures force. We expect this dual z-detection to be useful in a broad array of applications that demand precise tip-sample control, including tip-based nanofabrication and single-molecule force spectroscopy.
Ontogeny of estrogen binding sites in the brain of gray short-tailed opossums (Monodelphis domestica)

Abstract This study evaluated the binding of [ 3 H]estradiol to brain cytosols from gray short-tailed opossums ranging in age from newborn to 63 days postnatal. Estrogen binding was undetectable in whole-brain cytosol of newborn opossums. By postnatal day 4, high affinity ( K d = 0.2 nM), saturable ( B max = 3 fmol/mg protein) estrogen binding sites were present, and estrogen binding in whole-brain remained low but detectable (2–5 fmol/mg) through day 63. In contrast, estrogen binding sites in the hypothalamus-preoptic area increased substantially from 3.4 fmol/mg on day 16 to 14 fmol/mg by day 63.
A Statistical Test of Network Analysis: Can it Detect Differences in Food Web Properties?

Ecological network analysis (ENA) is a modeling approach increasingly being used to examine food webs. However, most studies do not replicate networks, and a statistical evaluation of ENA is lacking. The major objectives of this study, therefore, were to evaluate statistically the effectiveness of ENA in detecting differences in food web properties and to compare ENA output with established community level indices. Quantitative trophic networks (n = 12) representing four high salt marsh ponds during three times (corresponding to low stress, high stress, and post-disturbance) were constructed from an extensive field sampling program augmented by literature values. Food webs of salt marsh ponds were used because these systems contain relatively simple food webs, have well defined boundaries, and allow for adequate replication. A null hypothesis was tested to determine how values of 12 indices from ENA output differed among the three stress/disturbance conditions (H o: low stress = high stress = post-disturbance). Results of both ANOVA and Friedman’s tests indicated most ENA indices were significantly different among the three stress/disturbance conditions. The amount of covariance among the indices was relatively low (7 of 66 were significant). Results were compared to differences in community indices (richness, evenness, and diversity) among the three stress/disturbance conditions. ENA output identified differences beyond those recognized by the community indices. Overall, networks were unique enough under different environmental conditions to provide statistically significant differences in ENA results. Our findings are supportive of the use of carefully constructed networks in food web analysis and for decision making in ecosystem-based management.
Density functional study of the lithiation of cyclic vinyl ethers in solution

Abstract Lithiation of three cyclic vinyl ethers—2,3-dihydrofuran, 3,4-dihydro-2H-pyran, and 2,3-dihydrooxepin in ethereal solution are investigated at the density functional theory level of B3LYP/6-31++G(d,p). Several solvation models were used, including the microsolvation model, the continuum models such as the Onsager model, the polarized continuum models, and the isodensity polarized continuum model, and the mixed discrete-continuum model. Both the microsolvation and the mixed discrete-continuum model gave results consistent with experiments. Theoretical calculations also indicate that lithiation of 2,3-dihydrooxepin undergoes allylic lithiation concomitant with ring opening.
Seroprevalence of ovine progressive pneumonia virus and other selected pathogens in California cull sheep

Abstract An abattoir-based serosurvey was done to determine the point prevalence rate of antibodies to ovine progressive pneumonia virus (OPPV) in California sheep flocks, to detect differences in seroreactivity between primarily sheep-raising regions of the state, and to detect associations between infection with OPPV and serologic evidence of exposure to several other infectious agents. The overall seroprevalence of OPPV amongst sheep in this study was 43%. There was no significant difference in the prevalence of antibodies to OPPV between the two regions. In the analysis of independence of OPPV seroreactivity with other infectious agents, the chi-square test suggested an association between the presence of antibodies to OPPV and the presence of antibodies to Corynebacterium pseudotuberculosis . The relative risk was 1.35.
The evolutionary history of the genus Acanthamoeba and the identification of eight new 18S rRNA gene sequence types

The 18S rRNA gene (Rns) phylogeny of Acanthamoeba is being investigated as a basis for improvements in the nomenclature and taxonomy of the genus. We previously analyzed Rns sequences from 18 isolates from morphological groups 2 and 3 and found that they fell into four distinct evolutionary lineages we called sequence types T1-T4. Here, we analyzed sequences from 53 isolates representing 16 species and including 35 new strains. Eight additional lineages (sequence types T5-T12) were identified. Four of the 12 sequence types included strains from more than one nominal species. Thus, sequence types could be equated with species in some cases or with complexes of closely related species in others. The largest complex, sequence type T4, which contained six closely related nominal species, included 24 of 25 keratitis isolates. Rns sequence variation was insufficient for full phylogenetic resolution of branching orders within this complex, but the mixing of species observed at terminal nodes confirmed that traditional classification of isolates has been inconsistent. One solution to this problem would be to equate sequence types and single species. Alternatively, additional molecular information will be required to reliably differentiate species within the complexes. Three sequence types of morphological group 1 species represented the earliest divergence in the history of the genus and, based on their genetic distinctiveness, are candidates for reclassification as one or more novel genera.
Preparation of Ethyl Hypophosphite1,2

Abstract We report a convenient synthesis of ethyl hypophosphite by the O-alkylation of sodium hypophosphite (eq 1). Thus, when sodium hypo-phosphite is allowed to react with triethyloxonium tetrafluoroborate in methylene chloride at 0°, simple filtration from the inorganic salts and evaporation of the solvent gives the pure ester in 80% yield. This simple preparation employs readily available starting materials3.
Simulation of the effect of variation in the cooling cycle on the state of cure in a rubber component

The distribution of state of cure in a molded rubber component is usually nonuniform due to slow heat transfer processes involved in the molding/cooling cycle. In certain molding processes, the cure accumulated during the cooling process that occurs after a molding cycle can be a significant part of the total. In this work, prior simulation of the state of cure profile developed in a one-dimensional rectangular geometry is extended to consider the effect of the cooling conditions on the distribution of the state of cure. In addition, the effect of manufacturing process variation on the resulting state of cure distribution and the viability of the molding process is examined. Recommendations are made to minimize the effect of variation in process conditions.
Human Dose–response Curves for Neuromuscular Blocking Drugs: A Comparison of Two Methods of Construction and Analysis

This study was done to demonstrate the validity of the log-probit method of analyzing dose–response data and to test the accuracy of the incremental dose method for generating dose–response data for pancuronium and d-tubocurarine. During balanced general anesthesia, cumulative dose–response data were obtained from ten patients each for pancuronium and d-tubocurarine. Dose–response data were also obtained using a single bolus injection method in 46 patients given pancuronium and 27 patients given d-tubocurarine. Evoked thumb adduction response was measured using an FT-10 force-displacement transducer and recorded on a Grass®-7 polygraph. Dose–response data were plotted on log-probit paper and analyzed by the Litchfield-Wilcoxon approximation method to determine mean ED50 and ED95 for each muscle relaxant. The dose–response data were also plotted on arithmetic scales and analyzed by the linear regression method to determine ED50 and ED95. These results were compared with those obtained by use of the log-probit method. The validity of the incremental dose method of obtaining dose–response curves was determined by comparison with the dose–response curves obtained using the conventional single bolus injection method. For each neuromuscular relaxant studied, the mean dose–response curve obtained by the cumulative dose method was not statistically significantly different from the bolus method dose–response curve. Comparing methods of analysis, the log-probit method yields results that are statistically not different from those obtained by use of conventional linear regression analysis. The log-probit plot is a simple, accurate, appropriate approach for analyzing neuromuscular relaxant dose–response data. The log-probit curve yields results that are not statistically significantly different from those of the linear regression method, and is a better fit to the data at the clinically important extremes (85–99 per cent) of the response scale. For pancuronium and d-tubocurarine, the incremental dose method is efficient and accurate for generating dose–response curves.
Increasing the Print Focus of Adult-Child Shared Book Reading Through Observational Learning

An instructional strategy for increasing adults’ verbal and nonverbal references to print while reading to typically developing 4-year-old children was evaluated. Also investigated were the effects...
Differences in American and British Vocabulary: Implications for International Business Communication

American English and British English vocabularies have diverged over time, result, ing in lexical differences that have the potential to confound English-language intercultural communication. The differences derive from the need to adapt the meanings of existing expressions or to find new expressions for different things and to borrow expressions from different cultures. Separation and slow means of com munication also cause differences and encourage one side to retain archaic expres sions that others have abandoned or modified. The differences in vocabulary can be grouped into four categories: the same expression with differences in style, con notation, and/or frequency; the same expression with one or more shared and dif ferent meanings; the same expression with completely different meanings; and dif ferent expressions with the same shared meaning. These differences in vocabularies affect understanding of all varieties of English. To bridge differences in Enghsh language vocabularies, international busi...
Calorigenesis of brown adipose tissue in cold-exposed rats.

Brown adipose tissue calorigenesis related to total heat production of rats during acute cold exposure
Ultrafast nonlinearities in semiconductor laser amplifiers.

The bound-electronic optical nonlinearities in highly excited semiconductors (i.e., semiconductor lasers) have been calculated using a two-parabolic-band model. The nonlinear absorption spectrum is first obtained using a dressed-state formalism taking into account the contributions from two-photon absorption, electronic Raman, and optical Stark effects. The nonlinear refractive index (${\mathit{n}}_{2}$) is then found by performing a Kramers-Kronig transformation on the nonlinear absorption spectrum. It is also shown that the quadratic Stark splitting of the bands leads to a shift in the quasi-Fermi levels, which introduces additional absorptive and refractive nonlinearities. The sign, magnitude, and the current-density dependence of the calculated ${\mathit{n}}_{2}$ agree well with some recently published experimental results for Al-Ga-As and In-Ga-As-P diode lasers.
Film Photography Is Dead: Long Live Film: What can Digital Photography Learn from the Film Era?

The paper reviews the technological development in photography. The authors discusses different aspects of photography such as film photography, optical imaging, and digital photography.
Experience with rituximab immunotherapy as an early intervention in patients with Rai stage 0 to II chronic lymphocytic leukemia

BACKGROUND: Management of asymptomatic early stage chronic lymphocytic leukemia (CLL) centered on expectant surveillance for active disease warranting chemotherapy. In CLL, elevated serum β-2 microglobulin (β2M) levels were associated with more rapid disease progression and shorter survival (OS). METHODS: An early intervention trial was designed to assess response, time-to-progression (TTP), and OS after immunotherapy with standard-dose rituximab (375 mg/m2 intravenously weekly for 8 consecutive weeks) in 34 asymptomatic untreated early stage CLL with β2M level ≥ 2 mg/dL. RESULTS: Long-term follow-up and results are reported. The overall response rate in 34 patients was 82% (9% complete [CR]), median TTP in the 28 responders was 23 months, the median time to subsequent treatment was 43 months, and the 8-year OS rate was 74% (median follow-up, 102 months). CONCLUSIONS: Early treatment with rituximab was well tolerated and safe. Further studies are needed to determine if this intervention can decrease CLL-related morbidity and mortality. Cancer 2011. © 2011 American Cancer Society.
Information systems development as social action: Theoretical perspective and practice

Abstract Information systems development (ISD) continues to receive considerable attention in the literature. Much of it, however, simply perpetuates the myth that ISD should somehow be conceived in technical terms. In this paper, we challenge this view by presenting systems development as a form of social action. The hypothesis offered is that ISD can be more effectively understood by applying seven basic building blocks of social action theories: Knowledge, Power, Subjective Meanings, Human Interests, Consensus, Conflict, and Resistance. It is the interplay of these seven elements which make up the fundamental basis of systems development. To show that our understanding of ISD is enhanced through viewing it as social action, we present evidence from four case studies. It is shown that the practice of systems development is reflected in our notion of social action; more specifically, that it makes sense to view information systems development as social action.
People who were obese tried diets but felt they needed ongoing support to empower them to make lifestyle changes.

How do people who are obese describe their experiences with weight loss solutions? What do they think may help them to lose weight? Qualitative study. Victoria, Australia. Convenience and purposive sample of 76 people (mean age 47 y, 83% women) who had a body mass index ⩾30. Data were collected in face-to-face or telephone interviews. Interviews were audiotaped and transcribed. Data were analysed thematically using constant comparison. (1) Motivations for dieting included overall health and well-being, advice from healthcare professionals, and social acceptance. One participant stated, “…I really am sticking to the diet to get this weight off so I can fit into a skirt that I want to wear.” (2) Weight loss techniques . Participants progressed from “fad” diets as teenagers to more commercialised diets, such as Weight Watchers and Jenny Craig . For many, diet groups were a social activity shared with family and friends. Some participants felt a sense of belonging in such groups; however, groups could also reinforce low self-esteem, negative feelings, and self-blame. …
Applications of Embryo Transfer and Related Technologies to Cattle

It is possible to recover embryos from superovulated cows nonsurgically, divide each embryo in half, and routinely obtain pregnancy rates of greater than 50% per half embryo after nonsurgical transfer, which is equivalent to greater than 100% per original embryo. It is also possible to freeze and sex embryos, although the cryopreservation process kills some embryos and the sexing process is so new that efficacy under field conditions is unknown. Embryo transfer techniques are applied to thousands of dairy cows, but in 1982 only about one dairy calf per thousand born in North America was from embryo transfer. Nevertheless, use of this technology is increasing, in part because of simplification of procedures, increased efficacy, and lower costs. It is difficult to predict when additional technologies will become available for commercial use, but it is likely that several additional exciting developments will occur in cattle breeding before the end of the century.
Differential regulation of seizure activity in the hippocampus of male and female rats

Abstract OBJECTIVE: The aim of the current study was to directly examine and compare the susceptibility to N-methyl-D-aspartate-induced seizures in male versus female rats. We Also sought to compare the anticonvulsant effects of magnesium sulfate in these two groups. STUDY DESIGN: Eighteen female and 10 male rats were stereotaxically implanted with a chronic bipolar recording electrode in the hippocampus and an injection cannula in the lateral cerebral ventricle. After 1 week rats randomly received an intravenous injection of 90 mg/kg magnesium sulfate or saline solution control. Fifteen minutes after the infusion rats were given the convulsant N-methyl-D-aspartate at a dose of 5 μg/μl by direct intraventricular injection. Electrical seizure activity was thereafter assessed for 20 minutes. All data were analyzed by the Mann-Whitney U test and Student t test. RESULTS: In saline solution-treated rats receiving the convulsant N-methyl-D-aspartate, females had significantly lower total duration ( p p p p p CONCLUSION: N-methyl-D-aspartate-induced seizure activity is more severe in males versus female rats. Magnesium sulfate's effect on N-methyl-D-aspartate-induced seizures is also dependent on gender. We speculate that seizure regulation may be hormonally influenced.
The efficacy of behavioral interventions to modify dietary fat and fruit and vegetable intake: a review of the evidence.

Background. The evidence suggesting that nutrition, particularly dietary saturated fat and fruit and vegetable intake, is related to chronic disease risk has prompted considerable research on behavioral interventions focusing on dietary change. No clear understanding has emerged, however, of the degree to which these interventions can materially influence dietary change, or the types of intervention that are most effective and for whom. Therefore, the primary objective of the current study was to evaluate the overall effectiveness of behavioral dietary interventions in promoting dietary change related to chronic disease risk reduction. A secondary goal was to explore the relative effectiveness of specific intervention features and among different population subgroups. Methods. We conducted an evidence-based review and secondary analysis of existing literature. Our data sources included reports of randomized controlled trials and other study designs identified from multiple searches of MEDLINE, EMBASE, PsycINFO, CINAHL, AGELINE, and AGRICOLA. We included all studies on humans (including children, adolescents, and adults) published in English since 1975 that had been conducted in North America, Europe, or Australia; that had sample sizes of at least 40 subjects at follow-up; that were not based on controlled diets; and that otherwise met inclusion criteria. Through dual review, we abstracted detailed information on study characteristics, methodology, and outcomes relating to consumption of fruits, vegetables, and fats. Results. From 907 unduplicated articles originally identified, we retained 104 articles reporting on 92 independent studies. The studies were similarly successful in reducing intake of total and saturated fat, and increasing fruit and vegetable intake. More than three-quarters of the studies (17 of the 22 reporting results for fruit and vegetable intake) reported significant increases in fruit and vegetable intake, with an average increase of 0.6 servings per day. Similar consistent decreases were seen in intake of saturated fat and total fat (7.3% reduction in the percentage of calories from fat). Interventions appeared to be more successful at positively changing dietary behavior among populations at risk of (or diagnosed with) disease than among general, healthy populations. Two intervention components seemed to be particularly promising in modifying dietary behavior—goal setting and small groups. Conclusions. The majority of the interventions reviewed resulted in meaningful improvements in dietary factors behaviors associated with the prevention of chronic disease, particularly among individuals at elevated disease risk. The lack of similarity across studies in outcome measures, study design, analysis strategy, and intervention technique hampered our ability to draw broad conclusions about the most effective behavioral dietary interventions, but our findings offer insight into intervention components that may hold promise for future research efforts.
Making images by hand and by code: motivating students with multi-language interactive media application scripting (abstract only)

Calls are growing for computer science faculty to build a citizenry who are fluent with information technology and able to think computationally. While one might hope that our students would naturally understand the importance of such knowledge, many do not. CS faculty must therefore find ways to motivate such students.In this project, we explore interactive scripting, scripting done while working in an application. Scripting applications allows non-programmers to explore creative spaces and more efficiently accomplish many tasks. The interactive scripting model allows students to mix work they do normally ("by hand") with scripts that they write to better interact with the system ("by code"). Rather than focusing on one language or programming environment, we explore a multilingual approach that supports scripting in the environment the student (or their professor) considers appropriate. The success of the Media Computation approach leads us to focus on media applications, primarily image making and manipulation.We describe our experience (1) developing and using libraries to support interactive scripting in a functional language and an object-oriented language; (2) extending two open-source graphics applications, the GNU Image Manipulation Program and Inkscape, to support interactive multilingual scripting and (3) building novice-friendly examples and procedures.
Stochastic processes of soil production and transport: erosion rates, topographic variation and cosmogenic nuclides in the Oregon Coast Range

Landscapes in areas of active uplift and erosion can only remain soil-mantled if the local production of soil equals or exceeds the local erosion rate. The soil production rate varies with soil depth, hence local variation in soil depth may provide clues about spatial variation in erosion rates. If uplift and the consequent erosion rates are sufficiently uniform in space and time, then there will be tendency toward equilibrium landforms shaped by the erosional processes. Soil mantle thickness would adjust such that soil production matched the erosion. Previous work in the Oregon Coast Range suggested that there may be a tendency locally toward equilibrium between hillslope erosion and sediment yield. Here results from a new methodology based on cosmogenic radionuclide accumulation in bedrock minerals at the base of the soil column are reported. We quantify how soil production varies with soil thickness in the southern Oregon Coast Range and explore further the issue of landscape equilibrium. Apparent soil production is determined to be an inverse exponential function of soil depth, with a maximum inferred production rate of 268 m Ma−1 occurring under zero soil depth. This rate depends, however, on the degree of weathering of the underlying bedrock. The stochastic and large-scale nature of soil production by biogenic processes leads to large temporal and spatial variations in soil depth; the spatial variation of soil depth neither supports nor rejects equilibrium morphology. Our observed catchment-averaged erosion rate of 117 m Ma−1 is, however, similar to that estimated for the region by others, and to soil production rates under thin and intermediate soils typical for the steep ridges. We suggest that portions of the Oregon Coast Range may be eroding at roughly the same rate, but that local competition between drainage networks and episodic erosional events leads to landforms that are out of equilibrium locally and have a spatially varying soil mantle. Copyright © 2001 John Wiley & Sons, Ltd.
Epitope specificity and TCR Vβ gene utilization in the encephalitogenic response of B10.RIII(71NS)/SnJ mice

A high proportion of peptide 1-11 specific T cells from H-2u (V beta 8+, H-2u) mice express the V beta 8 TCR chain. Peptide 89-101 is immunodominant for B10.RIII (V beta 8+, H-2r) mice; thus, it was of interest to determine whether V beta 8 TCR would be over-represented in a population of peptide 89-101-specific T cells of this strain. Second, it was asked whether MBP peptides other than 89-101 would induce EAE in these mice. Of 70 B10.RIII(71NS)/SnJ mice immunized with mouse myelin basic protein (MBP), 32 of 41 males (78%) and 11 of 29 females (38%) showed clinical signs of experimental allergic encephalomyelitis (EAE). All mice immunized with peptide 89-101 showed clinical signs. One of six mice immunized with peptide 91-103 showed clinical signs, and 9 of 16 mice, all males, responded with EAE when immunized with peptide 38-88. No clinical EAE was observed in mice immunized with peptide 43-67, 68-88, 55-74, 1-37 or 1-20. A peptide 89-101-specific T cell line was established. At the initial stimulation the line was 29% V beta 8+ versus 21% in normal controls, and the line did not transfer EAE adoptively. After five in vitro stimulations, the percentage of V beta 8+ T cells had increased to 54%, and the line was encephalitogenic. Encephalitogenicity was partially blocked by anti-V beta 8 monoclonal antibody. Thus, over-representation of V beta 8+ TCR by encephalitogenic peptide-specific T cells is not limited to peptide 1-11-specific T cells from H-2u mice.(ABSTRACT TRUNCATED AT 250 WORDS)
Raman Effect as a Method of Analysis of Amino Acid Solutions

THE possibility of using the Raman effect for quantitative analysis depends upon two conditions: (1) The components of the mixture in question should possess distinguishable spectra, a requirement depending on the nature of the molecules. (2) The photographed spectra should be sufficiently intense and the background clear enough to provide good microphotometer measurements. The accompanying account concerns an investigation of these conditions in the case of amino acid solutions.
Unified Formulation for High-Order Streamline Tracing on Two-Dimensional Unstructured Grids

Accurate streamline tracing and travel time computation are essential ingredients of streamline methods for groundwater transport and petroleum reservoir simulation. In this paper we present a unified formulation for the development of high-order accurate streamline tracing algorithms on unstructured triangular and quadrilateral grids. The main result of this paper is the identification of velocity spaces that are suitable for streamline tracing. The essential requirement is that the divergence-free part of the velocity must induce a stream function. We recognize several classes of velocity spaces satisfying this requirement from the theory of mixed finite element methods and, for each class, we obtain the precise functional form of the stream function. Not surprisingly, the most widely used tracing algorithm (Pollock's method) emanates in fact from the lowest-order admissible velocity approximation. Therefore, we provide a sound theoretical justification for the low-order algorithms currently in use, and we show how to achieve higher-order accuracy both in the streamline tracing and the travel time computation.
Fully relativistic energy bands and cohesive energy of ReSi2.

Using the semirelativistic norm-conserving pseudopotential, we calculate, self-consistently, the equilibrium bond length and symmetrical optical-phonon frequency of ${\mathrm{ReSi}}_{2}$. At the equilibrium bond length, fully relativistic calculations of the energy bands, projected densities of states, cohesive energy, bonding charge density, and Fermi surface are performed. The results are compared with previous calculations for ${\mathrm{MoSi}}_{2}$ and ${\mathrm{WSi}}_{2}$, the only other silicides with the same crystal structure.
High-Temperature Thermosetting Polyimide Nanocomposites Prepared with Reduced Charge Organoclay

The naturally occurring sodium and calcium cations found in bentonite clay galleries were exchanged with lithium cations. Following the cation exchange, a series of reduced charge clays were prepared by heat treatment of the lithium bentonite at 130 C, 150 C, or 170 C. Inductively coupled plasma (ICP) analysis showed that heating the lithium clay at elevated temperatures reduced its cation exchange capacity. Ion exchange of heat-treated clays with either a protonated alkyl amine or a protonated aromatic diamine resulted in decreasing amounts of the organic modifier incorporated into the lithium clay. The level of silicate dispersion in a thermosetting polyimide matrix was dependent upon the temperature of Li-clay heat treatment as well as the organic modification. In general, clays treated at 150 C or 170 C, and exchanged with protonated octadcylamine or protonated 2,2'-dimethlybenzidine (DMBZ) showed a higher degree of dispersion than clays treated at 130 C, or exchanged with protonated dodecylamine. Dynamic mechanical analysis showed little change in the storage modulus or T(sub g) of the nanocomposites compared to the base resin. However, long term isothermal aging of the samples showed a significant decrease in the resin oxidative weight loss. Nanocomposite samples aged in air for 1000 hours at 288 C showed of to a decrease in weight loss compared to that of the base resin. This again was dependent on the temperature at which the Li-clay was heated and the choice of organic modification.
Optimal harvesting strategies for stochastic competitive Lotka-Volterra ecosystems

This work develops optimal harvest strategies for Lotka-Volterra systems so as to establish economically, ecologically, and environmentally reasonable strategies for populations subject to the risk of extinction. To better reflect reality, a continuous-time Markov chain is used to model the random environment. The underlying systems are thus controlled regime-switching diffusions that belong to the class of singular control problems. Starting with a model having multiple species, we construct upper bounds for the value functions, prove the finiteness of the harvesting value, and derive properties of the value functions. Then we construct explicit chattering harvesting strategies and the corresponding lower bounds for the value functions by using the idea of harvesting only one species at a time. We further show that this is a reasonable candidate for the best lower bound that one can expect. Moreover, in some cases, the lower bounds provide a good approximation of the value functions.
Determination of Bounds on Performance Measure and Min-Max Controllers in Time-Lag Systems

The effect of bounded deterministic disturbances (external and/or internal) on a chosen performance index (PI) is investigated. Upper and lower bounds of the PI about a nominal value are determined by the application of the optimum control theory. A computational procedure is also proposed to determine an approximately optimal feedback controller for time-lag systems. Such a controller is designed here on the basis of min-max criteria. Numerical examples illustrate the proposed approach.
A preliminary investigation of cognitive and relaxation treatment of panic disorder: Effects on intense anxiety vs ‘background’ anxiety

Abstract In this study, three adult males complaining of Panic Disorders were treated with cognitive therapy followed by relaxation training combined with cognitive therapy in a multiple-baseline across S s design. All S s demonstrated a decrease in the number and duration of episodes of heightened or intense anxiety, which was maintained at 3-month follow-up. Daily time-sampled ratings of ‘background’ anxiety, not necessarily associated with periods of intense anxiety, showed a substantial decrease for S 2, which was maintained at 3-month follow-up. However, S 1 and S 3 evidenced an increase in background anxiety during the combined treatment phase in contrast to the effects of treatment on periods of ‘intense’ anxiety. These results suggest that psychological treatments for patients classified as suffering from Panic Disorder are effective and lend some support to the differentiation of panic from ‘general’ anxiety. Recent observations of relaxation-induced anxiety were also replicated in this clinical setting. These data also illustrate the advantages and difficulties of self-monitoring anxiety over a period of time.
Purification and properties of human intestine alanine aminopeptidase

Abstract Human intestinal alanine aminopeptidase has been purified to greater than 90% homogeneity. The enzyme was released from mucosal cell membranes by Triton X-100 treatment. The native enzyme had a molecular weight of 206 000 in dilute buffer and 108 000 in the presence of sodium dodecyl sulfate. The enzyme was inhibited by chelators suggesting the presence of a metal ion in the enzyme. The most potent chelator inhibitor tested, o -phenanthroline, gave mixed kinetics ( K i = 67 μ M). Activity was restored by removal of the chelator. The enzyme was inhibited competitively by amino acids having hydrophobic side chains such as l -phenylalanine ( K i = 0.67 mM). Puromycin and methicillin also inhibited the enzyme in the competitive ( K i = 12.5 μ M) and noncompetitive ( K i = 4.6 mM) manner, respectively. Kinetic analysis of several amino acid β-naphthylamides as substrates demonstrated the preference for substrates having hydrophobic or basic amino terminal residues with no β-branching. l -Methionyl-β-naphthylamide was the most tightly bound while l -alanyl-β-naphthylamide was the most rapidly hydrolyzed.
Human Factors in Electronics-Historical Sketch

The growth of the new science dealing with manmachine relationships is traced from the first organized efforts during World War II to the present. The current rapid growth is underlined by the organization of professional societies, the largest of which is the IRE Professional Group on Human Factors in Electronics. The discussion includes reference to the several government, university and industrial laboratories which have pioneered in this field.
INVERTED CONTRAST MEDIUM‐URINE LAYERING IN THE CANINE URINARY BLADDER ON COMPUTED TOMOGRAPHY

Contrast medium-urine layering is routinely identified on transverse computed tomography (CT) images in the urinary bladder following intravesicular or intravenous administration of iodinated contrast medium. The contrast opacified urine typically occupies the dependent portion of the urinary bladder whereas the nonopacified urine layers above it. In this retrospective study, three patients with inverted contrast medium layering following intravenous contrast medium administration are described. A review of this phenomenon in humans is presented and an explanation for similar imaging findings in the dog proposed.
Surface ablation of porcine skin tissue using nanosecond laser pulses at 1064 nm

A selective photothermolysis model has been widely used to explain skin tissue ablation by nanosecond laser pulses. Nevertheless, fundamental questions regarding the mechanism underlying the ablation process remain to be answered. We have investigated the surface ablation of fresh porcine skin tissue with 8 ns pulses at 1064 nm and its dependence on spot size. Histology analysis of the ablated tissue samples has been conducted. From these preliminary results we have plotted the ablation depth per pulse as a function of laser fluence at different spot sizes.
The effect of prior night call status on the American Board of Surgery in-training examination scores: eight years of data from a single institution.

Purpose Despite recent attention to resident duty hours, little data evaluate the effect of being on-call the night before taking an in-training examination on examination performance. The few previous studies evaluated single-year test scores, from heterogeneous cohorts, with inconsistent findings. The purpose of this study was to determine the effect of being on-call the night before taking the American Board of Surgery In-Training Examination (ABSITE) on resident scores at a single institution over a duration of several years. Methods Overall percentile rank, standard scores, and prior night call status were recorded for all residents (categorical and preliminary) taking the ABSITE at our institution from 1999 to 2006. A 2-way ANOVA was performed to determine whether (1) the standard scores varied significantly between residents not on-call and those who were on-call, 2) performance varied significantly by PGY level, and 3) there was a significant interaction between call status and PGY level. Percentile rank of residents on-call the night before the examination were compared with those off-call using the Mann-Whitney U-test. For residents with scores from multiple years, standard scores from years on-call were compared with years off-call using the Wilcoxon signed rank test. Results A total of 282 ABSITE results were recorded with 69 (24%) residents taking in-house call the night before the examination. A 2-way analysis of variance indicated that although standard score performance varied significantly by PGY level (p Conclusions Based on several analytic models, being on-call the night before the ABSITE does not significantly affect resident performance.
Interaction of purulent material with antibiotics used to treat Pseudomonas infections

To define factors contributing to the adverse prognosis of patients with gram-negative bacillemia and abscess formation, we studied the interaction between polymyxin B, colistin sulfate, gentamicin, or carbenicillin with purulent material. Carbenicillin activity was not significantly altered by incubation with pus. Equal volumes of antibiotic and purulent sediment decreased the effective concentration of polymyxin B, colistin sulfate, or gentamicin from 100 μg/ml to 3 to 6 μg/ml. One milliliter of purulent sediment bound more than 700 μg of gentamicin and 1,500 μg of polymyxin B or colistin sulfate. This effect occurred rapidly, proceeded at 4 and 37 C, was stable for 24 to 48 h, and was altered, but not abolished, by varying the pH of the solution. Antibiotic activity could be removed from pus by high concentrations of protamine sulfate, heparin, sodium chloride, or potassium chloride, suggesting binding rather than inactivation.
TU-EE-A3-04: Cone Beam CT Imaging Versus Digital Tomosynthesis: A Computer Simulation Study for Comparisons

Purpose: We used a general-purpose PC cluster to develop a parallel computer simulation model for comparisons between the cone beam CT imaging and digital tomosynthesis with the same image acquisition geometry. Method and Materials: Our model incorporates quantum noise, detector blurring, and additive system noise into the computer simulation. Radon transforms formalism was applied to analytically calculate the phantom image projection data which were then used to reconstruct the volumetric images for low contrast performance and image quality studies. Feldkamp algorithm was used in the cone beam CT imaging, while the shift-and-add, filtered backprojection, and optimization based algorithms were used in digital tomosynthesis. We implemented a parallel random number generator based on the Weyl sequence to simulate both quantum and system noise. For digital tomosynthesis, we used blurring profiles and the artifact spread function (ASF) to quantify the magnitude of the out-of-plane artifacts. We also calculated the noise power spectra to characterize the image quality for cone beam CT imaging and digital tomosynthesis. Some artifacts removal methods and programming optimization techniques were also investigated in this study. Results: The test results showed that our parallel random number generator had good randomness quality and can be used in the noise study. The images reconstructed from using the digital tomosynthesis algorithms were worse than the Feldkamp algorithm in the cone beam CT imaging. However, it was possible to remove the out-of-plane blurring in digital tomosynthesis by using some special techniques. Conclusion: We had successfully developed a parallel computing technique to simulate quantum noise, detector blurring, and system noise for both cone beam CT imaging and digital tomosynthesis. Several quantification methodologies were used to compare these two 3D imaging techniques. Supported in part by a research grant EB000117 from the NIBIB and a research grant CA104759 from the NCI.