cssi/SciSciGPT-SciSciNet huggingface dataset:
Colonoscopic diagnosis and treatment of arteriovenous malformations in chronic lower gastrointestinal bleeding. Clinical accuracy and efficacy.

The authors reviewed their experience with diagnosis and treatment of lower gastrointestinal bleeding secondary to colonic arteriovenous malformations (AVM). A diagnosis was established exclusively by endoscopy in 80 percent of the patients. Twenty-eight patients were treated by endoscopic coagulation; bleeding stopped after one or more treatments in 67.9 percent of these patients. There were no complications or mortality as a consequence of endoscopic treatment. Surgery controlled the recurrent bleeding in six of seven cases of failed endoscopic coagulation, and in 13 of 17 cases where surgery only was undertaken, for an overall success rate of 79.2 percent. It is concluded that colonoscopy can accurately establish the diagnosis of colonic AVMs in chronic lower gastrointestinal bleeding. Endoscopic coagulation is a useful adjunct in the treatment of this condition, and is safe, effective, and leaves other options open.
Implications of electrically-induced action potential prolongation for reentry induction in the heart

We have investigated the effects of electric field stimulation on repolarlzation of the myocardial action potential, and assessed the consequences of these effects for reentry induction around a critical point in the heart.
The Integrating and Segregating Effects of School Choice

We evaluate the integrating and segregating effects of three distinct school choice programs in San Diego. We go beyond the traditional question of racial integration and examine the integration of students by test scores, parental education levels, and language status. In addition to measuring the net integrative effects of school choice, we also examine the underlying motives behind student participation in school choice programs and the limiting influence of supply-side constraints. Two of the programs that we consider are rooted in 1970s integration-based reforms that provide public transportation for program participants. The third program is a state-mandated, open-enrollment program that requires participants to find their own transportation to and from their choice schools. We find that the two programs with underlying integrative objectives do indeed integrate the district, but the open-enrollment program segregates the district along most dimensions. Provision of busing and geographic preferences...
Fractionation and comparison of proteins from bovine uterine fluid and bovine allantoic fluid

Serum, allantoic fluid and uterine washings obtained from cows at various stages of pregnancy were fractionated by gel filtration and the fractions compared by electrophoretic and immunological methods. Several proteins were detected in uterine washings which were not found in serum. Some of these proteins were sensitive to the experimental conditions used for concentrating the uterine washings, being irreversibly adsorbed onto the glass containers on freeze drying. The number and imtensity of the "uterine-specific" proteins varied with the stage of pregnancy, changes in the electrophoretic patterns being detected just prior to rapid elongation of the embryo and at a stage when luteolysis would have occurred in the unmated cow. Many of the "uterine-specific" proteins were also detected in allantoic fluid.
Sagittal growth trends of the craniofacial complex during formation of the secondary palate in mice.

Normal C57BL and A/J mice and A/Js with spontaneous bilateral cleft lip and palate were obtained at 13–16 days of gestation and the heads were prepared for serial sectioning in the sagittal plane. The midsagittal sections were photographically enlarged and measurements made to assess the amount and rate of growth. The C57BL fetuses outgrew the A/Js. in all parameters. A mandibular growth spurt was not observed, but an increase in mandibular growth relative to that of the maxilla was found. Maxillary growth was less in malformed A/Js but the mandible was not micrognathic. The cranial base angle was not significantly different in normal and malformed A/J fetuses, but the vertical dimension was significantly greater in the former than the latter at days 15 and 16. The increase in the angle made by the mandible and the posterior cranial base before and during palatal closure appeared to have the greatest influence on the vertical dimension.
CD80 and CD86, but not CD154, augment DNA vaccine-induced protection in experimental bovine tuberculosis.

DNA vaccination is known to elicit robust cellular and humoral responses to encoded antigen. The co-administration of costimulatory molecules CD80 (B7-1), CD86 (B7-2) and CD154 (CD40L) has been shown to enhance immune responses in several murine models. The role of specific costimulatory molecules in non-rodent species remains incompletely characterized. In these studies, we demonstrate that the co-administration of CD80 and CD86, but not CD154, to an existing candidate subunit DNA vaccine (ESAT-6) against bovine tuberculosis, enhances protection after aerosol challenge with virulent Mycobacterium bovis. Additionally, we have shown that vaccination with M. bovis BCG is protective against tuberculosis following aerosol challenge in cattle. Two independent trials were conducted in cattle to determine the adjuvant effect of encoded antigen + CD80/CD86 and directly compare the adjuvant activities of CD80/CD86 to those of CD154. Co-administration of either CD80/CD86 or CD154 enhanced ESAT-6-specific IFN-γ responses as compared to animals vaccinated with ESAT-6 DNA alone. However, following aerosol challenge, only animals vaccinated with CD80/CD86 possessed decreased pathology of the lungs and associated lymph nodes, as measured by gross examination, radiographic lesion morphometry and bacterial recovery. Collectively, these results demonstrate that the co-administration of costimulatory molecules with a protective antigen target enhances bovine immune responses to DNA vaccination, and that CD80/CD86 is superior to CD154 in augmenting DNA vaccine-induced protection in experimental bovine tuberculosis.
Unraveling bisphenol A pharmacokinetics using physiologically based pharmacokinetic modeling

Physiologically based pharmacokinetic (PBPK) models integrate both chemical- and system-specific information into a mathematical framework, offering a mechanistic approach to predict the internal dose metrics of a chemical and an ability to perform species and dose extrapolations. Bisphenol A (BPA), because of its ubiquitous presence in a variety of consumer products, has received a considerable amount of attention from the public and regulatory bodies. PBPK models using deuterated BPA were developed for immature and adult rats and non-human primates and for adult humans to understand better the dosimetry of BPA. The focus of the present paper is to provide a rationale for interpreting species- and age-related pharmacokinetics of BPA. Gastrointestinal tract metabolism was an important consideration to predict unconjugated BPA serum kinetic profiles in adult and immature rats and monkeys. Biliary excretion and enterohepatic recirculation of BPA conjugates accounted for the slowed systemic clearance of BPA conjugates in rats. For monkeys, renal reabsorption was proposed as a mechanism influencing systemic clearance of BPA conjugates. The quantitative understanding of the processes driving the pharmacokinetics of BPA across different species and life stages using a computational modeling approach provides more confidence in the interpretation of human biomonitoring data and the extrapolation of experimental animal findings to humans.
Thermal enzymes. VI. Heat stability of pyruvic oxidase.

Abstract The pyruvic oxidase system found in a cell particle obtained from Bacillus stearothermophilus is easily inactivated at the growing temperatures of the organism (60–65 °C.) unless magnesium ions, pyruvate, and oxygen are present. Pyruvic oxidase is the only enzyme (or system) thus far found in this organism that is sensitive to destruction by heat in the temperature range of optimum growth.
Pharmacologic Receptor Activity of Rabbit Aorta Effect of Dithiothreitol and N-Ethylmaleimide

N-ethylmaleimide (NEM), an alkylating agent that covalently binds sulfhydryl groups, and dithiothreitol (DTT, Cleland's reagent), which reduces disulfide bridges to sulfhydryl groups, affected drug-induced contractions of rabbit aorta. NEM depressed aortic responses to potassium chloride (KCl), norepinephrine, serotonin, histamine, and angiotensin II. This action was attributed to an interaction of NEM with sulfhydryl groups vital to either the membrane function or the contractile apparatus. DTT had minimal effects on responses to KCl, norepinephrine, and serotonin; it potentiated aortic contractions produced by histamine and abolished responses to angiotensin II. Enhancement of the histamine response by DTT was not accompanied by an effect on the histamine-metabolizing enzymes or by an alteration in the KB and pA2 values for pyrilamine. The results suggest that a disulfide bridge plays a prominent role in both histamine and angiotensin receptor activity of rabbit aorta. With regard to the histamine recep...
Discrepancy between cytotoxicity and DNA interstrand crosslinking of carboplatin and cisplatin in vivo

We used the method of alkaline elution to compare quantitatively the DNA lesions produced by cisplatin and carboplatin in the AKR leukemia in vivo. These data were compared with cytotoxicity of each drug in the same animal model and in a solid tumor murine model (colon 26).
Identification of new QTLs for seed mineral, cysteine,and methionine concentrations in soybean[Glycine max (L.) Merr.]

Increased concentrations of important nutrients in edible parts of plants could result in biofortified foods. Soybean [Glycine max (L.) Merr.] is a major legume crop and an important source of certain nutrients, including protein and minerals, in human and animal diets. Understanding the underlying genetic basis of seed composition is crucial to improving seed nutrient composition. In this study we used three soybean recombinant inbred line mapping populations derived from the crosses Williams 82 × DSR-173, Williams 82 × NKS19-90 and Williams 82 × Vinton 81, and constructed a joint linkage map from these populations. Forty quantitative trait loci (QTLs) were detected for 18 traits: seed weight, seed magnesium, sulfur, calcium, manganese, potassium, iron, cobalt, nickel, copper, zinc, selenium, molybdenum, cadmium and arsenic concentrations, total nitrogen:total sulfur (N:S) ratio, cysteine and methionine concentrations. Using the joint linkage map, we detected nine QTLs that were not identified in the individual populations. We identified several candidate genes that might contribute to these traits, including transporters and genes involved in nitrogen and amino acid metabolism. Some strong QTLs had no obvious candidate genes, offering the possibility that subsequent confirmation of these QTLs may result in identification of new genes affecting seed nutrients in soybean. Seed weight and seed mineral concentrations were not highly correlated, suggesting the possibility of improving seed mineral concentrations without significant changes in seed weight. An inverse relationship between N:S ratio and most other minerals suggests the possibility of using N:S ratio as an indirect measure of seed mineral concentration in soybean breeding programs.
On the formation of isolated Se8 rings in zeolites

Abstract Even at sub-stoichiometric Se loading into the supercages of Sr–Y zeolite, significant concentrations of Se 8 rings form in addition to the open chain structures. This material provides an excellent medium for the investigation of the vibrational and UV/VIS absorption spectra of isolated Se 8 molecules under well-defined conditions. The potential of these nanostructured composite materials has not yet been fully exploited, and a complete understanding of the molecular structure of such encapsulates is prerequisite for tailoring new materials for optoelectronic purposes.
Use of Quantitative Real-Time PCR to Investigate the Dynamics of the Red Tide Dinoflagellate Lingulodinium polyedrum

A new method based on quantitative real-time polymerase chain reaction (qPCR) was developed and applied to quantify the red tide dinoflagellate Lingulodinium polyedrum in natural seawater samples and in laboratory cultures. The method uses a Molecular Beacon™ approach to target a species-specific region of the small subunit ribosomal RNA gene. The accuracy of the method was verified by microscopical counts using cultures of the dinoflagellate isolated from coastal waters near Los Angeles, CA, and with natural water samples spiked with cultured L. polyedrum. The method was applied to document the pattern and timing of vertical migration by the dinoflagellate in a 2-m water column on an 11:13 h light/dark photoperiod established in the laboratory. Positive phototaxis of L. polyedrum resulted in dense aggregations of the dinoflagellate within the top few centimeters of the water column during the light period. This pattern of distribution was readily established by both methods, although abundances of L. polyedrum determined using qPCR were higher than abundances determined by microscopy in the morning and lower in the afternoon and evening. These differences may have been a consequence of variability in the DNA content per cell because of synchrony of cell division. Counts using both methods to analyze natural samples collected from coastal waters in the Long Beach–Los Angeles area and adjacent San Pedro Channel were in close agreement. However, the qPCR method exhibited greater sensitivity than the microscopical method when L. polyedrum was present at low abundances, and qPCR had a much higher rate of sample throughput than microscopy. The development of this new approach for enumerating L. polyedrum provides a useful tool for studying the ecology of this important red tide species.
GPR identification of an early monument at Los Morteros in the Peruvian coastal desert

Abstract Los Morteros (8˚39′54″S, 78˚42 ′00″W) is located in coastal, northern Peru, one of the six original centers of world civilization. The site consists of a large, sand-covered, isolated prominence situated on a Mid-Holocene shoreline, ∼ 5 km from the present coast. Preceramic archaeological deposits (4040 ± 75 to 4656 ± 60 14 C yr BP or ∼ 3600–5500 cal yr BP) cap this feature, which has been identified by prior researchers as a sand-draped, bedrock-cored landform or a relict dune deposit. Because neither explanation is geomorphologically probable, we used ground-penetrating radar (GPR) and high-resolution mapping to assess the mound's interior structure. Our results indicate an anthropogenic origin for Los Morteros, potentially placing it among the earliest monumental structures in prehistoric South America. The extremely arid setting raises new questions about the purpose and the logistics of early mound construction in this region. This work demonstrates the value of an integrated Quaternary sciences approach to assess long-term landscape change and to understand the interaction between humans and the environment.
Seasonal trends in sleep-disordered breathing: evidence from Internet search engine query data.

The primary aim of the current study was to test the hypothesis that there is a seasonal component to snoring and obstructive sleep apnea (OSA) through the use of Google search engine query data. Internet search engine query data were retrieved from Google Trends from January 2006 to December 2012. Monthly normalized search volume was obtained over that 7-year period in the USA and Australia for the following search terms: “snoring” and “sleep apnea”. Seasonal effects were investigated by fitting cosinor regression models. In addition, the search terms “snoring children” and “sleep apnea children” were evaluated to examine seasonal effects in pediatric populations. Statistically significant seasonal effects were found using cosinor analysis in both USA and Australia for “snoring” (p < 0.00001 for both countries). Similarly, seasonal patterns were observed for “sleep apnea” in the USA (p = 0.001); however, cosinor analysis was not significant for this search term in Australia (p = 0.13). Seasonal patterns for “snoring children” and “sleep apnea children” were observed in the USA (p = 0.002 and p < 0.00001, respectively), with insufficient search volume to examine these search terms in Australia. All searches peaked in the winter or early spring in both countries, with the magnitude of seasonal effect ranging from 5 to 50 %. Our findings indicate that there are significant seasonal trends for both snoring and sleep apnea internet search engine queries, with a peak in the winter and early spring. Further research is indicated to determine the mechanisms underlying these findings, whether they have clinical impact, and if they are associated with other comorbid medical conditions that have similar patterns of seasonal exacerbation.
A large solid angle electron detector with very low sensitivity to γ-rays

Abstract A large solid angle detector consisting of a hin crystal of anthracene coupled to a fast photomultiplier by an air-filled light guide has been designed and constructed for use in experiments which require the detection of electrons of positrons from the internal pair decay of excited nuclear levels in coincidence with nuclear reaction products. The primary design considerations were high efficiency for electrons and low sensitivity to γ rays. In tests involving the first excited 0 + state of 16 O an efficiency of (31.9 ± 0.6)% was observed; γ rays from the nearby second excited state were detected with a sensitivity approximately 100 times smaller.
The survival of religious peace movements: When mobilization increases as political opportunity decreases:

Research on social movement life-cycles specifies four stages of movement progression: emergence, rise, decline, and dormancy. This article challenges conventional perspectives on the final stage o...
Optimization of left ventricular ejection fraction measurement by two-dimensional echocardiography in patients with repaired tetralogy of Fallot: comparison of geometric methods with cardiovascular magnetic resonance

In patients with repaired tetralogy of Fallot (rTOF), left ventricular ejection fraction (LVEF) predicts adverse clinical outcomes. Cardiovascular magnetic resonance (CMR) is the gold standard for LVEF measurement, but two-dimensional echocardiography (2DE) is commonly used for serial evaluatio no f LVEF. The optimal 2DE method for LVEF measurement and limiting factors in this population are not known. Methods This single-center retrospective study included all patients with rTOF with CMR performed 2007-2010 without general anesthesia and 2DE within 3 months of CMR, with adequate images for analysis by all 2DE methods. Two investigators blinded to CMR results measured LVEF from 2DE studies by biplane Simpson’s (BiS) method (using apical 4-chamber and apical or parasternal 3-chamber images), 5/6 area*length (AL), and visual estimate. Two investigators blinded to 2DE results measured LVEF from CMR by Simpson’s method, as well as by AL, to test validity of geometric assumptions. An investigator re-evaluated each modality at least one month later. Results In 20 patients (28.5±14.7 years old, 40% female), visual estimation by 2DE best approximated LVEF by CMR
Erratum: The toxic mind: the biology of mental illness and violence

Abstract The continual suppression of emotions during fight or flight reactions results in atrophy and endogenous toxicosis in noradrenergic neurons. Diminished synaptic levels of norepinephrine are associated with depression. During periodic detoxification crises excess norepinephrine and other metabolites flood synapses. The norepinephrine overexcites postsynaptic neurons and causes symptoms ranging from mild anxiety to violent behavior. Some of the other metabolites, which may include dopamine, epinephrine, serotonin, gamma-aminobutyric acid, peptides, amino acids, and various metabolic waste products, are bound by noradrenergic receptors and alter neurotransmission. When they prevent norepinephrine from exciting postsynaptic neurons, depression returns. A mechanism is proposed for the binding of norepinephrine and for the effects of the other metabolites, many of which have been thought to be neurotransmitters. The diverse receptor proteins presumed to be specific for false neurotransmitters may instead encode specific memories. The shift in depressive and excitatory behavior is characteristic of nearly all nervous and mental disorders, including addictions, Alzheimer’s disease, Parkinson’s disease, and psychosomatic disorders. When toxins accumulate in regions of the brain that control specific activities, the symptoms observed will be related to those activities, giving rise to supposedly distinct disorders that represent the same detoxification process. Recovery can be facilitated by therapy and self-help measures that involve the releasing and redirecting of repressed emotions. Full text: http://homepages.nyu.edu/~er26/toxicmind.html
Ultrafast Photoinduced Charge Separation Resulting from Self-assembly of a Green Perylene-based Dye into π-Stacked Arrays

Condensation of 3,4,5-tris(n-dodecyloxy)aniline with the green chromophore 1,7-bis(N-pyrrolidinyl)perylene-3,4;9,10-tetracarboxylic dianhydride yields N,N‘-bis(3,4,5-tris(n-dodecyloxy)phenyl)-1,7-bis(N-pyrrolidinyl)perylene-3,4;9,10-bis(dicarboximide), 5PDI-TAP, which absorbs light strongly from 550 to 750 nm. 5PDI-TAP dissolves readily in methylcyclohexane (MCH), resulting in self-assembly into H-aggregates. Small-angle X-ray scattering data obtained on 10-4 M solutions of 5PDI-TAP in MCH show that the aggregates are π-stacked monodisperse pentamers. Femtosecond transient absorption spectroscopy on solutions of (5PDI-TAP)5 in MCH shows evidence of charge separation occurring with τ ≤ 150 fs between adjacent stacked members of 5PDI-TAP within the pentamer followed by charge recombination with τ = 860 ps. Transmission electron microscopy of 5PDI-TAP films cast from solution show isolated bundles of columnar aggregates. (5PDI-TAP)n is a potentially useful material for organic photovoltaics because efficient...
Power Savings of a Variable Recruitment Hydraulic Artificial Muscle Actuation Scheme

We investigate utilizing inelastic bladder hydraulic artificial muscle actuators as muscle fibers. These muscle fibers are then grouped together to form a variable recruitment artificial muscle bundle. This muscle bundle configuration is biologically inspired, where in skeletal muscle, different numbers of motor units are recruited to match the load by increasing the number of motor neurons firing. This results in extremely efficient locomotion in nature. It is desired to use a similar methodology to increase the actuation efficiency of valve-controlled hydraulic systems. Such hydraulic control systems induce a pressure drop in the valves to throttle the flow to the cylinder actuators. Using the valves in this manner is simple but very inefficient. Hence, this paper presents selectively recruiting different numbers of the hydraulic artificial muscle fibers to match a required loading scenario similar to our bipedal robot. By using fewer of the muscle fibers to match a smaller load, less power is consumed from the hydraulic power unit because instead of inducing a pressure drop, the volume of fluid delivered is decreased. The potential efficiency improvements associated with this actuation scheme is compared to a traditional hydraulic system with differential cylinders.Copyright © 2014 by ASME
Soot Aerosol Properties in Laminar Soot-Emitting Microgravity Nonpremixed Flames

The spatial distributions and morphological properties of the soot aerosol are examined experimentally in a series of 0-g laminar gas-jet nonpremixed flames. The methodology deploys round jet diffusion flames of nitrogen-diluted acetylene fuel burning in quiescent air at atmospheric pressure. Full-field laser-light extinction is utilized to determine transient soot spatial distributions within the flames. Thermophoretic sampling is employed in conjunction with transmission electron microscopy to define soot microstructure within the soot-emitting 0-g flames. The microgravity tests indicate that the 0-g flames attain a quasi-steady state roughly 0.7 s after ignition, and sustain their annular structure even beyond their luminous flame tip. The measured peak soot volume fractions show a complex dependence on burner exit conditions, and decrease in a nonlinear fashion with decreasing characteristic flow residence times. Fuel preheat by approximately 140 K appears to accelerate the formation of soot near the flame axis via enhanced fuel pyrolysis rates. The increased soot presence caused by the elevated fuel injection temperatures triggers higher flame radiative losses, which may account for the premature suppression of soot growth observed along the annular region of preheated-fuel flames. Electron micrographs of soot aggregates collected in 0-g reveal the presence of soot precursor particles near the symmetry axis at midflame height, The observations also verify that soot primary particle sizes are nearly uniform among aggregates present at the same flame location, but vary considerably with radius at a fixed distance from the burner. The maximum primary size in 0-g is found to be by 40% larger than in 1-g, under the same burner exit conditions. Estimates of the number concentration of primary particles and surface area of soot particulate phase per unit volume of the combustion gases are also made for selected in-flame locations.
On the random allocation design for the control of selection bias in sequential experiments

SUMMARY In comparing two treatments, suppose that eligible subjects come to the experiment sequentially and must be treated immediately. In this paper we assume that the experimenter selects 2n subjects and treat n subjects with each treatment. If, during the experiment, the experimenter knows or guesses which treatment is to be administered next, he may bias the experiment by his selection of subjects. The problem is how to control this bias through choice of design. In this paper, a design criterion is derived. Under this criterion the random allocation design is superior to the truncated binomial design which has been shown to be the minimax one by Blackwell & Hodges (1957) under their design criterion.
Energy balance and the speed of crack growth in a compressed plate with delamination

Abstract The evolution of the crack growth speed in a buckled one-dimensional delamination model is studied and two approximate solutions are presented. In the quasi-dynamic analysis one assumes that the time-dependent deflection of the delaminated layer may be approximated by the static postbuckling solution for the current delamination length. In a refined analysis one introduces an indeterminate amplitude function. The local growth condition at the crack tip is not enforced but a global energy-balance condition is used. The crack growth speeds are found to be comparable to the speeds of flexural waves. For slow and moderate rates of crack growth, the present results are in close agreement with the finite-difference solutions of the dynamic problem.
Metabolic resting-state brain networks in health and disease

The delineation of resting state networks (RSNs) in the human brain relies on the analysis of temporal fluctuations in functional MRI signal, representing a small fraction of total neuronal activity. Here, we used metabolic PET, which maps nonfluctuating signals related to total activity, to identify and validate reproducible RSN topographies in healthy and disease populations. In healthy subjects, the dominant (first component) metabolic RSN was topographically similar to the default mode network (DMN). In contrast, in Parkinson’s disease (PD), this RSN was subordinated to an independent disease-related pattern. Network functionality was assessed by quantifying metabolic RSN expression in cerebral blood flow PET scans acquired at rest and during task performance. Consistent task-related deactivation of the “DMN-like” dominant metabolic RSN was observed in healthy subjects and early PD patients; in contrast, the subordinate RSNs were activated during task performance. Network deactivation was reduced in advanced PD; this abnormality was partially corrected by dopaminergic therapy. Time-course comparisons of DMN loss in longitudinal resting metabolic scans from PD and Alzheimer’s disease subjects illustrated that significant reductions appeared later for PD, in parallel with the development of cognitive dysfunction. In contrast, in Alzheimer’s disease significant reductions in network expression were already present at diagnosis, progressing over time. Metabolic imaging can directly provide useful information regarding the resting organization of the brain in health and disease.
Analysis and classification of delay-sensitive cortical neurons based on response to temporal parameters in echolocation signals

Abstract Echolocating bats generate an acoustic image of their target by processing target-reflected echoes of their emitted biosonar pulses. Efforts in building computational models of auditory processing in the bat auditory system, using extensive neurophysiological data from cortical studies are challenged by the intrinsic complexity and the significant variability in neural response to stimuli. In this paper, we use a computerized method for the analysis and classification of delay-sensitive neurons to classify neurons from the auditory cortex of Myotis lucifugus, a species that echolocates with FM signals. The coefficients of the bi-linear fit to the best delay response surfaces (mean R2 = 0.01) were used in classifying the neurons. Six classes were derived that corresponded to the four previously characterized neuropysiologically. The first class corresponded to delay-tuned neurons which exhibited a constant best delay at different pulse repetition rates and pulse durations. Three other classes corresponded to the different subtypes of tracking neurons which changed their best-delay to one or both of these stimulus temporal parameters. Two additional classes were differentiated although their best-delay response were similar to either the delay-tuned or the duration and pulse-repetition rate sensitive class. Artificial delay-sensitive neurons built from the parameters of the centroid of each class, will serve a key role in the bat auditory system model that we are building.
Progress in self-quenching InP-based single photon detectors

The operation of InP-based single photon avalanche diodes (SPADs) in Geiger mode provides great utility for the detection of single photons at near-infrared wavelengths between 1.0 and 1.6 μm. However, SPADs have performance limitations with respect to photon counting rate and the absence of photon number resolution that, at the most fundamental level, can be traced back to the positive feedback inherent in the impact ionization-driven avalanche process. In this paper, we describe the inclusion of negative feedback with best-in-class InP-based single photon avalanche diode (SPAD) structures to form negative feedback avalanche diodes (NFADs) in which many of the present limitations of SPAD operation can be overcome. The use of thin film resistors as monolithic passive negative feedback elements ensures rapid self-quenching with very low parasitic effects. We demonstrate a qualitative difference in the performance of NFADs in the two regimes of small and large negative feedback. With small feedback, we have studied the behavior of the persistent current prior to quenching, for which we have found oscillatory behavior as well as an exponentially distributed duration. For large feedback, we find rapid quenching, accompanied by evidence for a partial discharge of the detector capacitance, leading to charge flows as low as ~3 ×105 carriers associated with each avalanche event.
Chromosome breakage hotspots and delineation of the critical region for the 9p-deletion syndrome.

Summary The clinical features of the 9p-deletion syndrome include dysmorphic facial features (trigonocephaly, midface hypoplasia, upward-slanting palpebral fissures, and a long philtrum) and mental retardation. The majority of these patients appear to have similar cytogenetic breakpoints in 9p22, but some cases show phenotypic heterogeneity. To define the breakpoints of the deleted chromosomes, we studied 24 patients with a deletion of 9p, by high-resolution cytogenetics, FISH with 19 YACs, and PCR using 25 different sequence-tagged sites. Of 10 different breakpoints identified, 9 were localized within an ∼5-Mb region, in 9p22-p23, that encompasses the interval between D9S1869 (telomeric) and D9S162 (centromeric). Eight unrelated patients had a breakpoint (group 1) in the same interval, between D9S274 (948h1) and D9S285 (767f2), suggesting a chromosome-breakage hotspot. Among 12 patients, seven different breakpoints (groups 3–9) were localized to a 2-Mb genomic region between D9S1709 and D9S162, which identified a breakpoint-cluster region. The critical region for the 9p-deletion syndrome maps to a 4–6-Mb region in 9p22-p23. The results from this study have provided insight into both the heterogeneous nature of the breakage in this deletion syndrome and the resultant phenotype-karyotype correlations.
Nuclear excitation by 1 MeV to 3 MeV electrons

Abstract A calculation by Robl of the cross-section for nuclear excitation by low-energy electrons has been tested for states with measured lifetimes in Li7, In115 and Cd111. The inelastic electron scattering cross-section for 3 MeV electrons agrees with theory for the 0.478 MeV states of Li7. The total cross-sections for electron excitation of In115 and Cd111 was larger than expected by an order of magnitude near threshold. Agreement is obtained if the Robl cross-section is multiplied by F(Z, p) S L (L) F(Z, p 0 ) where F(Z, p) is the Fermi function and SL(L) is the forbidden s-spectrum shape factor. Photon absorption measurements gave g Γ 0 =(2.8±0.8)×10 −4 eV and g Γ 0 =(1.8±0.6)×10 −3 eV for the 1.07 MeV and 1.46 MeV states of In115.
Rhetoric versus Reality Rogue States in Interstate Conflict

The term rogue statehas become part of the common language of American foreign policy, and the assumptions made by policy makers about the international conduct of these actors—that they represent ...
Analytical and numerical results for first escape time in 2D

Abstract We consider the problem of a particle subject to Brownian motion in a 2D circular domain with reflecting boundaries except for an absorbing gate. An exact solution for the mean first escape time is given for a gate of any size. Also obtained is the exact probability density of the location of an exiting particle. Numerical simulations of the stochastic process with finite step size are compared with the exact solution to the Brownian motion (the limit of zero step size). The difference between the two appears to decrease with diminishing step size.
CORRELATION OF SELECTED WELL WATER QUALITY PARAMETERS WITH SOIL AND AQUIFER HYDROLOGIC PROPERTIES

: The geographical distribution of well water specific electrical conductivity and nitrate levels in a 932 km2 ground water quality study area in the Fresno-Clovis, California, indicated that frequently areas of lower ground water salinity were also areas of relatively greater soil and aquifer permeability. From these observations and certain assumptions we hypothesized that the quality of the well water should be better in areas with permeable soils and geological formations. Correlation and multiple linear regression analysis supported this hypothesis for well water salinity. However, well water nitrate levels were significantly negatively correlated with only the estimated equivalent specific yield of the aquifer system. The multiple R2 values of the most significant multiple linear regression models showed that only a fourth to a third of the variability in well water specific electric conductivity and nitrate levels could be ascribed to the effects of the hydrogeological parameters considered with more than 90 percent confidence. This indicates that three-fourths to two-thirds of the variability in ground water salinity and nitrate levels may be related to land use. Thus, there is considerable room for land use management techniques to improve ground water quality and reduce its variability.
High-efficiency gene targeting in Schizosaccharomyces pombe using a modular, PCR-based approach with long tracts of flanking homology.

Bahler et al.(1998) recently described a PCR-based system for the deletion, tagging and overexpression of endogenous genes in the fission yeast Schizosaccharomyces pombe. A small set of PCR primers can be used to generate gene-targeting substrates from each of several modules that differ in the selectable marker (ura4(+) or kanMX6), the presence or absence of specific epitope tags (HA, Myc, GST or GFP), the position in which the epitopes will be inserted (C- or N-terminal), and the presence or absence of a regulatable promoter (the nmt1 promoter). This is a straightforward and powerful system: nine different genes were C-terminal tagged at an average efficiency of 73%, using primers producing only 60-81 bp of homology. In contrast, when studying three transcriptionally-silent genes (rec8(+), rec10(+) and rec11(+)) we obtained an average homologous integration efficiency of 4% for 12 targeting constructs when using primers that contained 80 bp of homology. By using a PCR-based increase in the amount of flanking homology to >/=250 bp, we obtained homologous integration efficiencies of up to 100%. Thus, loci of S. pombe that are refractory to gene targeting when using short tracts of homology can be readily modified by increasing the extent of homology flanking the targeting modules. This straightforward and cost-effective approach might therefore be the one of choice for the modification of S. pombe loci in general and of targeting-refractory loci in particular.
Critical Stress: Police Officer Religiosity and Coping with Critical Stress Incidents

As a result of exposure to critical stress inducing incidents, police officers experience high rates of family disruption, alcohol abuse, domestic violence, and physical and psychological problems. This paper evaluates the ability of religion to mitigate the harmful consequences of critical stress using data obtained from a survey of metropolitan police officers (n = 811). Contrary to our expectations, we found less religious officer used more adaptive coping strategies when confronted by critical stress incidents than their more religious counterparts. Furthermore, we found Protestants employed more adaptive strategies than Catholics. Potential explanations for the unexpected findings are discussed.
Structure and Dynamics in an Urban Landscape: Toward a Multiscale View

Ecosystems and city systems often form hierarchically structured landscapes whose spatial pattern is scale dependent. While trends in the upper tail of national city-size distributions leave the impression that fractal-scaling laws such as Zipf’s law or the rank-size rule truly represent the essence of the system, the linearity depicted at aggregate scale actually obscures variation and discontinuity in the urban size-density function, including multimodalities evident in regional data sets. Tracing individual city trajectories through these hierarchical patterns reveals structural resilience at macroscopic scale, the punctuated growth of individual cities of differing sizes, the persistence and self-reinforcing character of spatial agglomeration, and a general need for further empirical investigation of the relationship between city size and growth. It also raises questions for future exploration, including the meaning of persistent departures from the power laws of traditional urban systems theory. Interpretation of such departures in the context of questions of jurisdictional scale in environmental management and “smart growth” policy adds a practical dimension to the research agenda.
Agreement about Identifying Patients Who Change over Time: Cautionary Results in Cataract and Heart Failure Patients

Background. Preference-based measures of health-related quality of life all use the same dead = 0.00 to perfect health = 1.00 scale, but there are substantial differences among measures. Objective. The objective was to examine agreement in classifying patients as better, stable, or worse. Methods. The EQ-5D, Health Utilities Index Mark 2 and Mark 3, Quality of Well-Being–Self-Administered scale, Short-Form 36 (Short-Form 6D), and disease-targeted measures were administered prospectively in 2 clinical cohorts. The study was conducted at academic medical centers: University of California, Los Angeles; University of California, San Diego; University of Wisconsin–Madison; and University of Southern California. Patients undergoing cataract extraction surgery with lens replacement completed the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25). Patients newly referred to congestive heart failure specialty clinics completed the Minnesota Living with Heart Failure Questionnaire (MLHF). In ...
The orientation of centrioles in migrating 3T3 cells

Abstract Based on electron microscopic examination of 20 migrating 3T3 cells, the paper suggests that one centriole of a pair is preferentially oriented perpendicular, the other parallel to the substrate. The finding is interpreted as further support for the possibility that centrioles are involved in the control of migration in 3T3 cells.
For Better or for Worse? Women's Autonomy and Marital Status in Zimbabwe☆☆☆★

This article explores the nature of women's autonomy in household decision making using data from the 1994 Zimbabwe Demographic and Health Survey. Using multivariate regression techniques, I compare women's autonomy across marital status, age at marriage, and duration of marriage, with particular attention to social context. Contrary to expectations, most women do not experience complete male domination of household decisions. Older single, divorced, and widowed women have a substantial amount of sole decision-making autonomy, while married women have input through joint decision making. Regardless of marital status, women who live with their parents are often not even consulted in major household decisions. This study shows that in Zimbabwe, marital status is a key predictor of decision making and that women may have incentives to alter their marital status to improve their degree of control over their lives.
COROTATION RESONANCE: UGC 2885 AND A NEW METHOD

Kinematic data on the minor axis of the giant sprial galaxy UGC 2885 show a change in the sign of the raidal velocity across spiral arms. Such a sign change indicates that corotation has been crossed. In fact, two sign changes are seen, implying that there are two spiral patterns. The morphology of the galaxy supports this interpretation. A general method is also presented that can be used to locate the corotation resonance in a grand design spiral galaxy. The method relies on the effects of geometric phase, and assumes only that the spiral flow is wave-based and periodic in azimuth.
Rapidly solidified nanocomposite SmCo7/fcc Co permanent magnets

Abstract High-remanent Sm–Co permanent magnetic alloys modified with Nb and C have been produced with isotropic grain structures consisting of 100–200 nm SmCo7 and 10–15 nm fcc Co phases, with the Co phase comprising only 2–4 vol%. Remanence ratios of 0.7 have been consistently observed, with coercive forces approaching 10 kOe.
Treatment with a sclerostin antibody increases cancellous bone formation and bone mass regardless of marrow composition in adult female rats.

Abstract The current report describes the skeletal effects of a sclerostin monoclonal antibody (Scl-AbIII) treatment at a yellow (fatty) marrow skeletal site in adult female rats. Ten-month-old female Sprague–Dawley rats were treated with vehicle or Scl-AbIII at 5 or 25 mg/kg, twice per week by s.c. injection for 4 weeks. Trabecular bone from a yellow (fatty) marrow site, the 5th caudal vertebral body (CVB), was processed undecalcified for quantitative bone histomorphometric analysis. Compared to vehicle controls, Scl-AbIII at both doses significantly increased bone formation parameters and trabecular bone volume and thickness and decreased bone resorption parameter in the trabecular bone of the CVB. As a reference, we also found that the Scl-AbIII at both doses significantly decreased bone resorption and increased bone formation and bone volume in a red (hematopoietic) marrow site, the 4th lumber vertebral body (LVB). It appears that the percentage of increase in trabecular bone volume induced by Scl-AbIII treatment was slightly larger in the LVB than in the CVB. In summary, these preclinical findings show that antibody-mediated sclerostin inhibition has significant bone anabolic effects at both red and yellow marrow skeletal sites.
Molecular Consequences of the BCR-ABL Translocation in Chronic Myelogenous Leukemia

The BCR-ABL translocation of chronic myelogenous leukemia represents a paradigm for the study of translocations that create fusion proteins. The work of many laboratories has clearly established that the BCR-ABL protein can transform cells and cause leukemias in mice. This oncogenic signal appears to involve transduction of a tyrosine kinase signal from the cytoplasm to the nucleus via intermediary proteins such as ras and myc. Although the biological effects of the BCR-ABL fusion protein are well characterized, the normal biological functions of ABL and BCR are only beginning to come to light. ABL is a nuclear tyrosine kinase which binds DNA, suggesting a possible normal role in transcription. BCR has homology to proteins which regulate membrane ruffling. Understanding the normal roles of ABL and BCR will help define the abnormal leukemogenic effects of the BCR-ABL fusion.
P07 Hydrogen sulfide relaxes intrapulmonary airways by inhibiting Ca2+ release through InsP3 receptors and Ca2+ oscillations in smooth muscle cells

Hydrogen sulfide (H2S) is a signaling molecule that regulates diverse cell physiological process in several organs and systems including vascular and airway smooth muscle cell (SMC) contraction. Decreases in endogenous H2S synthesis have been associated with the development of cardiovascular diseases and asthma. Here we investigated the mechanism of airway SMC relaxation induced by H2S in small intrapulmonary airways using mouse lung slices and confocal and phase-contrast video microscopy. Exogenous H2S (100 μM) reversibly inhibited Ca2+ release and airway contraction evoked by inositol-1,4,5-trisphosphate (InsP3) uncaging in airway SMCs. Similarly, InsP3-evoked Ca2+ release and contraction was inhibited by endogenous H2S precursor L-cysteine (10 mM) but not by L-serine (10 mM) or either amino acid in the presence of DL-propargylglycine (PPG). Consistent with the inhibition of Ca2+ release through InsP3 receptors (InsP3R), H2S reversibly inhibited acetylcholine (ACh)-induced Ca2+ oscillations in airway SMCs. In addition, exogenous H2S and L-cysteine caused relaxation of airways pre-contracted with either ACh or 5-hydroxytriptamine (5-HT). The effects of H2S on InsP3-evoked Ca2+ release and contraction as well as on the relaxation of agonist-contracted airways were mimicked by the thiol-reducing agent dithiothreitol (DTT, 10 mM) and inhibited by the oxidizing agent diamide (30 μM). These studies indicate that H2S causes airway SMC relaxation by inhibiting Ca2+ release through InsP3R and consequent reduction of agonist-induced Ca2+ oscillations in SMCs. These results suggest a novel role for endogenously produced H2S that involves the modulation of InsP3-evoked Ca2+ release —a cell-signaling system of critical importance for many physiological and pathophysiological processes.