cssi/SciSciGPT-SciSciNet huggingface dataset:
Source retrieval from broadband regional seismograms: Hindu Kush region

Abstract A method of relocation and source characterization of small earthquakes using one modern regional station is developed and tested. First, we model teleseismic body waves of two events, which are used as masters. Short period depth phases, pP and sP, are used to establish the epicentral depth, and the events are relocated using calibrated stations and a mantle model derived for this region, TIP. The events moved upward by 12 and 31 km, respectively. The regional waveforms recorded at the IRIS station GAR from the best-determined source are forward modeled to establish a local crustal model. A four-layered model with a thickness of 65 km proves effective. Synthetics from this crustal model can then be compared with the data from other events where the depths are poorly known, i.e. PDE depths of 33 km. Forward modeling of the short period phases allows better estimates of depth and makes relocation possible. Next, we perform a long period inversion of whole and partial waveform data to obtain source mechanism and moment, and repeat the procedure if necessary. This technique is applied to events in the tectonically active Pamir-Hindu Kush region to test its usefulness. Five crustal events sampling various azimuths are presented as examples of relocation and determination of source mechanisms from small events. The smallest event has a moment of 5.1 × 1022 dyn cm. For the seven events we studied, the average depth correction to PDE is 19 km, and the location correction is 11 km on average. The method can be used to identify earthquakes and thus it lowers the threshold below present mb: MS discrimination, since these events are too small to be seen teleseismically. Secondly, these events can be used as ‘masters’ in the calibration of other systems, case-based event characterizations, etc.
Primary steps in the oxidation of pyridine and pyrrole added to a lean methaneoxygenargon flame

Abstract An understanding of the fuel-nitrogen oxidation mechanism is important for modeling combustion of fuels containing nitrogen and for developing nitric oxide emission control strategies. The work reported here identifies the primary reactions for pyridine and pyrrole in a lean methaneoxygenargon flame. A major intermediate in the breakdown of pyridine in the flame. C3H5CN, was found to be the same as the product of the reaction of O(3P) with pyridine observed under single collision conditions. The analogous product of pyrrole oxidation in the flame, C2H5CN, was an isomer of the product observed from the reaction of O(3P) with pyrrole, C2H5NC. Other intermediates found in the early stages of the flame could be identified as reaction products of H and OH with pyridine and pyrrole. The important ring-opening step in the flame appears to be the decomposition of hydroxypyridine or hydroxypyrrole produced by the reaction of O(3P) or OH with pyrrole or pyridine.
Slow decomposition of silicone rubber

The sol content of previously extracted samples of lightly crosslinked silicone rubber has been found to increase during prolonged storage under relatively mild conditions. Simultaneously, the tensile stress slowly decreases in samples held stretched, and the equilibrium degree of swelling increases somewhat. Thus, the polymer network appears to undergo slow decomposition. This process is accelerated by moisture, by ammonia vapor, and by raising the temperature of storage. It is slowed down by prior treatment of the polymer with a silazane reagent which reduces the number of residual OH groups. It is therefore attributed to hydrolytic decomposition of the poly(dimethylsiloxane) molecules initiated by OH groups.
Polyphosphatase Activity of CthTTM, a Bacterial Triphosphate Tunnel Metalloenzyme

Triphosphate tunnel metalloenzymes (TTMs) are a superfamily of phosphotransferases with a distinctive active site located within an eight-stranded β barrel. The best understood family members are the eukaryal RNA triphosphatases, which catalyze the initial step in mRNA capping. The RNA triphosphatases characteristically hydrolyze nucleoside 5′-triphosphates in the presence of manganese and are inept at cleaving inorganic tripolyphosphate. We recently identified a TTM protein from the bacterium Clostridium thermocellum (CthTTM) with the opposite substrate preference. Here we report that CthTTM catalyzes hydrolysis of guanosine 5′-tetraphosphate to yield GTP and Pi (Km = 70 μm, kcat = 170 s-1) much more effectively than it converts GTP to GDP and Pi (Km = 70 μm, kcat = 0.3 s-1), implying that a nucleoside interferes when positioned too close to the tunnel entrance. CthTTM is capable of quantitatively cleaving diadenosine hexaphosphate but has feeble activity with shorter derivatives diadenosine tetraphosphate and diadenosine pentaphosphate. We propose that the tunnel opens to accommodate the dumbbell-shaped diadenosine hexaphosphate and then closes around it to perform catalysis. We find that CthTTM can exhaustively hydrolyze a long-chain inorganic polyphosphate, a molecule that plays important roles in bacterial physiology. CthTTM differs from other known polyphosphatases in that it yields a ∼2:1 mixture of Pi and PPi end products. Bacterial/archaeal TTMs have a C-terminal helix located near the tunnel entrance. Deletion of this helix from CthTTM exerts pleiotropic effects. (i) It suppresses hydrolysis of guanosine 5′-tetraphosphate and inorganic PPPi; (ii) it stimulates NTP hydrolysis; and (iii) it biases the outcome of the long-chain polyphosphatase reaction more strongly in favor of Pi production. We discuss models for substrate binding in the triphosphate tunnel.
Charge symmetry breaking in the valence quark distributions of the nucleon

Using a quark model, we study the effect of charge symmetry breaking on the valence quark distributions of the nucleon. The effect due to quark mass differences and the Coulomb interaction of the electrically charged quarks is calculated and, in contrast to recent claims, found to be small. In addition, we investigate the effect of charge symmetry breaking in the confining interaction, and in the perturbative evolution equations used to relate the quark model distributions to experiment. We find that both these effects are small, and that the strong charge symmetry breaking effect included in the scalar confining interactions may be distinguishable from that generated by quark mass differences. {copyright} {ital 1997} {ital The American Physical Society}
Illicit worlds of Indian dance: cultures of exclusion

The history of Indian dance as narrated in most twentieth-century texts (written by scholars such as and Mohan Khokar, and a number of classical dance practitioners, among others) is restricted to ...
The C-terminal domain of DNA gyrase A adopts a DNA-bending β-pinwheel fold

DNA gyrase is unique among enzymes for its ability to actively introduce negative supercoils into DNA. This function is mediated in part by the C-terminal domain of its A subunit (GyrA CTD). Here, we report the crystal structure of this ≈35-kDa domain determined to 1.75-A resolution. The GyrA CTD unexpectedly adopts an unusual fold, which we term a β-pinwheel, that is globally reminiscent of a β-propeller but is built of blades with a previously unobserved topology. A large, conserved basic patch on the outer edge of this domain suggests a likely site for binding and bending DNA; fluorescence resonance energy transfer-based assays show that the GyrA CTD is capable of bending DNA by ≥180° over a 40-bp region. Surprisingly, we find that the CTD of the topoisomerase IV A subunit, which shares limited sequence homology with the GyrA CTD, also bends DNA. Together, these data provide a physical explanation for the ability of DNA gyrase to constrain a positive superhelical DNA wrap, and also suggest that the particular substrate preferences of topoisomerase IV might be dictated in part by the function of this domain.
CD3 δ and ϵ gene expression in CD3t-CD16+ natural killer cell clones derived from thymic precursors

Abstract To better understand the maturational stages during T-cell development, we studied the expression of CD3δ and CD3ϵ genes, as well as the presence of TCR gene rearrangements, within CD3 − CD16 + NK clones derived from thymic precursors in vitro. Northern blot analysis revealed that CD3 − CD16 + clones derived from CD7 + CD3 − CD4 − CD8 − (TN) thymocytes expressed transcripts for the CD3ϵ gene; however, no transcripts for the CD38 gene were detected. Importantly, both the CD3ϵ and CD3δ genes were expressed in TN thymocytes examined prior to cloning. A CD7 + CD8 + CD3 − CD4 − thymocyte population that makes up only 0.4% of the total thymocyte pool was also isolated from human thymus. We determined the maturation potential of this CD7 + CDS + CD3 − CD4 − population by limiting dilution cloning and found that 67% of the clones generated in vitro had a CD3 − CD16 + CD8 + phenotype. In contrast to the NK clones derived from TN precursors, most CD3 − CD16 + clones derived from CD7 + CD8 + CD3 − CD4 − thymocytes expressed transcripts for both CD3ϵ and CD3δ genes. Southern blot analysis of the NK clones derived from either thymic precursor population revealed no rearrangement of the TCR β or γ genes. These results demonstrate that the TN progenitor population and their CD3 − CD16 + progeny differ in their expression of the CD38 transcript and during in vitro culture there is loss of CD38 expression and acquisition of surface CD16 within these NK clones. Furthermore, the CD3 − CD16 + clones derived from TN versus CD7 + CD8 + CD3 − CD4 − thymocytes differed in their expression of the CD38 gene. The signaling events regulating the expression of the CD3 invariant chain genes within immature lymphoid progenitor cells may be important in determining their eventual maturation into T-cell and NK-cell lineages in vivo.
Cow milk allergy in infancy and hypoallergenic formulas

Substitute feedings have been used to treat infants with cow milk protein allergy for most of this century. For the past 50 years, several infant formulas based on animal proteins, both intact and chemically modified, or on vegetable protein have been labeled "hypoallergenic." Because of the risk of anaphylaxis and other serious adverse reactions, formulas that are claimed to be hypoallergenic should be subjected to rigorous preclinical and clinical testing. At a minimum, such formulas should not provoke any allergic signs or symptoms in 90% of infants with documented cow milk protein allergy when tested in double-blind, placebo-controlled trials. A standardized definition of "hypoallergenic" will allow clinicians and parents to understand the true risks to a cow milk-allergic infant fed such hypoallergenic formulas.
A comparative study of stress‐induced crystallization of guayule, hevea, and synthetic polyisoprenes

A comparative study of the stress induced crystallization of natural (Hevea, Guayule) and synthetic high cis-1,4-polyisoprenes at room temperature is presented. Hevea and Guayule are both found using WAXS to crystallize into the unit cell of Morss and Bunn previously described for Hevea. DSC studies of polyisoprenes held at −25°C indicate that Hevea and Guayule crystallize more rapidly than synthetics. Studies of relative birefringence and stress decay following uniaxial extension confirm this. Under conditions of comparison at the same stress, raw Hevea crystallizes more rapidly than extracted Hevea, Guayule, and the other polyisoprenes.
Enhancement of single particle rare earth doped NaYF4: Yb, Er emission with a gold shell

Upconversion of infrared light to visible light has important implications for bioimaging. However, the small absorption cross-section of rare earth dopants has limited the efficiency of these anti-Stokes nanomaterials. We present enhanced excitation absorption and single particle fluorescent emission of sodium yttrium fluoride, NaYF4: Yb, Er based upconverting nanoparticles coated with a gold nanoshell through surface plasmon resonance. The single gold-shell coated nanoparticles show enhanced absorption in the near infrared, enhanced total emission intensity, and increased green relative to red emission. We also show differences in enhancement between single and aggregated gold shell nanoparticles. The surface plasmon resonance of the gold-shell coated nanoparticle is shown to be dependent on the shell thickness. In contrast to other reported results, our single particle experimental observations are corroborated by finite element calculations that show where the green/red emission enhancement occurs, and what portion of the enhancement is due to electromagnetic effects. We find that the excitation enhancement and green/red emission ratio enhancement occurs at the corners and edges of the doped emissive core.
Organizational gossip: A revolving door of regulation and resistance

Empirical studies of gossip are unusual in organizational communication, where gossip as a specific communicative practice has been largely ignored. This interpretive study was conducted with four organizations in various geographical regions in the United States: a manufacturing plant, an electrical utility, a worker‐owned restaurant, and a college. Thirty‐one narrators were asked to share their opinions about and experiences with gossip in their workplaces. Their accounts illustrate how gossip serves organizational regulation and individual resistance through its performance as a “gossip‐information revolving door” and through accounts of company (anti)heroes and cautionary tales, gossipy humor and nostalgia, and interpersonal maneuvers. Gossip can be understood in the context of organizational citizenship behaviors (OCBs) as “social capital” that enhances the organization or workplace deviance behaviors (WDBs) that detract from the desired goals of citizenry.
Thermospheric storms and related ionospheric effects

A comparative study of thermospheric storms for equinox and winter conditions is presented based on neutral-composition measurements from the Aeros-A neutral-atmosphere temperature experiment. The main features of the two storms as inferred from changes in N2, Ar, He, and O are described, and their implications for current theories of thermospheric storms are discussed. On the basis of the study of the F-region critical frequency measured from a chain of ground-based ionospheric stations during the two storm periods, the general characteristics of the ionospheric storms and the traveling ionospheric disturbances are described. It is suggested that the positive and negative phases of ionospheric storms are different manifestations of thermospheric storms.
Contour finish turning operations with coated grooved tools : Optimization of machining performance

This paper presents a new methodology for optimization of machining performance in contour finish turning operations. Two machining performance measures, chip breakability and surface roughness, are considered as optimization criteria due to their importance in finishing operations. Chip breakability covers two major factors: chip shape and size. Comprehensive case studies are presented to demonstrate the determination and application of optimal cutting conditions through experimental validation.
An electron microscopic study of structural changes during the large amplitude swelling and contraction of isolated beef-heart mitochondria

The structural changes of isolated beef-heart mitochondria undergoing hypotonic swelling and ATP-induced contraction are described. During swelling the mitochondria take up water, the matrix space enlarges, the inner membrane becomes greatly extended with material which is apparently derived from the cristae (the rest of which fragment) and the outer membrane is ruptured. On addition of ATP, Mn++ and Ca++ water is extruded as the extended inner membrane contracts around the remnants of the cristae to give compact bundles of vesicles which bear little resemblance to the original organized structure.
Sequential disassembly of vertebrate muscle thick filaments.

Abstract Native thick filaments from rabbit psoas muscle have been sequentially dissolved by incremental rises in salt concentration. Three quite separate stages of depolymerization can be detected; these presumably reflect constraints imposed on the disassembly process by variations in the packing of myosin and by the presence of other thick filament proteins.
Social influences on the sexual behavior of youth at risk for HIV exposure.

OBJECTIVES. Adolescents are increasingly at risk for infection with human immunodeficiency virus (HIV) and other sexually transmitted diseases, especially in poor urban minority communities. To aid the design of interventions in these communities, this study investigated the role of knowledge, attitudes, perceived parental monitoring, and peer behavior in the onset and progression of sexual behavior in children at risk for exposure to HIV. METHODS. A computerized personal interview was administered to 300 African-American 9- to 15-year-old children living in six public housing developments in a large US city. RESULTS. Although children's knowledge about the hazards of sex increased with age, their sexual activity also increased (from 12% sexually experienced at 9 years of age to more than 80% experienced at 15 years of age). Parental monitoring appeared able to influence sexual activity. However, the perceived behavior of friends was associated with the rate at which sexual activity progressed with age an...
SU-E-J-270: Study of PET Response to HDR Brachytherapy of Rectal Cancer

Purpose: Dose-response studies in radiation therapy are typically using single response values for tumors across ensembles of tumors. Using the high dose rate (HDR) treatment plan dose grid and pre- and post-therapy FDG-PET images, we look for correlations between voxelized dose and FDG uptake response in individual tumors. Methods: Fifteen patients were treated for localized rectal cancer using 192Ir HDR brachytherapy in conjunction with surgery. FDG-PET images were acquired before HDR therapy and 6–8 weeks after treatment (prior to surgery). Treatment planning was done on a commercial workstation and the dose grid was calculated. The two PETs and the treatment dose grid were registered to each other using non-rigid registration. The difference in PET SUV values before and after HDR was plotted versus absorbed radiation dose for each voxel. The voxels were then separated into bins for every 400 cGy of absorbed dose and the bin average values plotted similarly. Results: Individual voxel doses did not correlate with PET response; however, when group into tumor subregions corresponding to dose bins, eighty percent of the patients showed a significant positive correlation (R2 > 0) between PET uptake difference in the targeted region and the absorbed dose. Conclusion: By considering larger ensembles of voxels, such as organ average absorbed dose or the dose bins considered here, valuable information may be obtained. The dose-response correlations as measured by FDG-PET difference potentially underlines the importance of FDG-PET as a measure of response, as well as the value of voxelized information.
A distributed implementation of an adaptive finite element method for fluid problems

Abstract The potential for using a network of workstations for solving the incompressible Navier–Stokes equations using the finite element method is investigated. A programming paradigm suitable for a heterogeneous distributed workstation environment is presented and compared to the traditional paradigm employed for distributed memory parallel computers. In particular, the issues of load balancing and fault recovery are explored. Extension of the programming paradigms to include mesh adaptivity is discussed.
Power scintillations due to the wandering of the laser beam

The wandering of the laser beam causes a fading effect at the receiving terminal. A simple model is discussed to investigate the probability distribution of the power intercepted by a circular aperture.
Folded zoom lenses: a review of patent literature

Folded zoom lenses offer an interesting opportunity for a review of patent literature: they are of a reasonable complexity that the designs are likely to be instructive, they offer a small range of design constraints because of the standardization of CMOS imager sizes and the mechanical constraints imposed on DSC cameras, and there is enough recent activity in awarded patents that a representative sample of contemporary designs can be collected. This paper presents a review of recent patent literature for folded zoom lenses. Zemax models were built for the designs disclosed in 67 patents. For this large set of models, the distribution of paraxial properties and lens materials is presented. For the most-common design constraints, two particularly-similar disclosed designs are compared in detail. Engineering differences between the two disclosed designs are compared to differences in patent claims directed to the disclosed designs; the patents’ claims are shown to omit, at least for these two patents, some design differences that seem important from an engineering point of view.
Blood pressure but not parental history for hypertension predicts pain perception in women

Previous work has suggested an attenuated sensitivity to painful stimulation in hypertensive men. We recently reported that, compared with persons with negative parental history, men, but not women, with a positive history for hypertension showed attenuated pain perception. This study specifically addressed factors that predict pain perception in women, including blood pressure, parental history and mood states. Fifty-four normotensive women with positive (PH+; n=20) or negative parental history (PH−; n=34) for hypertension and high or low casual systolic blood pressure (BP) performed the cold pressor (CP) test. Participants rated their pain every 15 s during a 90-s hand CP (0–4°C) and a 90-s post-CP rest period. Detailed mood ratings were obtained immediately before the CP test. Data were evaluated using multivariate repeated measure analyses of variance and regression analyses. PH+ and PH− women did not differ in age, height, weight, education, resting BP, or heart rate. PH+ and PH− women did not differ in pain ratings during or after the CP, or pain ratings using the McGill Pain Questionnaire (MPQ), and they did not differ in their cardiovascular responses to the CP, confirming our earlier study in a separate sample. Women with high casual systolic BP reported significantly less pain, especially after the CP (P<0.01). MPQ total scores confirmed this finding with high BP women reporting less pain than low BP women (P<0.05). Regression analyses confirmed these effects. Controlling for potential confounding variables did not alter these relationships. These findings suggest that in women, phenotype systolic BP may be a better predictor of hypoalgesia than parental history of hypertension.
Atmospheric evolution of organic aerosol

[1] We report here results of an experimental study of the OH-initiated oxidation of solid organics in the presence of O2, NOx and H2O, using two kinds of self-assembled organic monolayers (alkane and aromatic), paraffin and pyrene films as proxies for organic aerosol. We show that the OH-initiated oxidation of the alkane surfaces leads to rapid volatilization. The gas-phase products detected include HO2, H2O2, CO, CO2, HCO, CH2O, CH3CHO, CH3OH, and HCOOH. We conclude that volatilization is at least as efficient as wet deposition as a removal process for aliphatic particulates, whereas aromatic particulates show higher stability towards volatilization.
Parathyroid hyperplasia in uremic rats precedes down-regulation of the calcium receptor

Parathyroid hyperplasia in uremic rats precedes down-regulation of the calcium receptor. Background Recent evidence points to a relationship between the down-regulation of the calcium-sensing receptor (CaR) and parathyroid cell hyperplasia that is associated with chronic renal failure. It is not known, however, if down-regulation of the CaR precedes, and perhaps initiates, parathyroid cell proliferation, or if a decrease in the expression of the CaR occurs subsequently to hyperplasia or the conditions promoting it. The current study examined the temporal relationship of these two events. Methods Rats were made uremic by subtotal nephrectomy and were ( 1 ) placed immediately on a high phosphate (HP) diet that promotes parathyroid gland hyperplasia, or ( 2 ) maintained on a low phosphate (LP) diet that inhibits development of secondary hyperparathyroidism before being switched to the HP diet. Serum chemistries and parathyroid gland (PTG) weights were examined; CaR content and parathyroid cell proliferation (PCNA/Ki-67) were analyzed by immunohistochemistry. Results When rats were nephrectomized and placed immediately on a HP diet, parathyroid cell proliferation was significantly increased by day 2 and continued to increase at day 4. CaR content was unchanged at 1 and 2 days post-nephrectomy, but fell by day 4. When nephrectomized rats were maintained for 1 week on a LP diet, then switched to a HP diet, an increase in parathyroid cell proliferation was again seen at day 2; down-regulation of the CaR did not occur until after 7 days of uremia and the HP diet. Conclusion These data indicate that parathyroid cell hyperplasia precedes down-regulation of CaR expression in the uremic rat model.
Bounded boxes, Hausdorff distance, and a new proof of an interesting Helly-type theorem

In the first part of this paper, we reduce two geometric optimization problems to convex programming: finding the largest axis-aligned box in the intersection of a family of convex sets, and finding the translation and scaling that minimizes the Hausdorff distance between two polytopes. These reductions imply that important cases of these problems can be solved in expected linear time. In the second part of the paper, we use convex programming to give a new, short proof of an interesting Helly-type theorem, first conjectured by Gru¨nbaum and Motzkin.
Therapeutic Inhibition of Platelet Function in Stroke

Platelet-dependent thrombotic- and thromboembolic-occlusive events are the usual cause of ischemic strokes. Antiplatelet strategies target one of the three platelet recruitment pathways (thromboxane A
RhoA as a Mediator of Clinically Relevant Androgen Action in Prostate Cancer Cells

Recently, we have identified serum response factor (SRF) as a mediator of clinically relevant androgen receptor (AR) action in prostate cancer (PCa). Genes that rely on SRF for androgen responsiveness represent a small fraction of androgen-regulated genes, but distinguish benign from malignant prostate, correlate with aggressive disease, and are associated with biochemical recurrence. Thus, understanding the mechanism(s) by which SRF conveys androgen regulation to its target genes may provide novel opportunities to target clinically relevant androgen signaling. Here, we show that the small GTPase ras homolog family member A (RhoA) mediates androgen-responsiveness of more than half of SRF target genes. Interference with expression of RhoA, activity of the RhoA effector Rho-associated coiled-coil containing protein kinase 1 (ROCK), and actin polymerization necessary for nuclear translocation of the SRF cofactor megakaryocytic acute leukemia (MAL) prevented full androgen regulation of SRF target genes. Andro...
Parturient Paresis. VII. A Study of the Leucocytes of Cows with Parturient Paresis

Summary A study was made of the reaction of the leucocytes to milk fever. The leucocyte reaction is similar to that obtained by an injection of ACTH. These results indicate that the stress of milk fever causes an increased secretion from the adrenal cortex.
Prolongation of simple and choice reaction times in a double-blind comparison of twice-daily hydroxyzine versus terfenadine.

Abstract Newer, nonsedating antihistamines provide a therapeutic alternative for the patient with allergy whose work is impaired by the side effects of traditional H 1 antihistamines. To assess the differential effect of these antihistamines on reaction times and subjective symptoms, we compared terfenadine, 60 mg twice daily, to hydroxyzine, 25 mg twice daily, in a double-blind, placebo-controlled, crossover study of 16 healthy, asymptomatic adults. Simple reaction time and choice reaction time were measured with a computer-based, eye-hand, reaction-time testing apparatus. Reaction times and symptom scores were assessed 90 minutes after the fourth and tenth doses of each drug. Hydroxyzine, but not terfenadine, significantly prolonged both simple and choice reaction time ( p ≤ 0.0001). However, decision time, the time to process one bit of spatial information, was not prolonged by either antihistamine. Therefore, hydroxyzine prolonged the interpretation and response to stimuli of the central nervous system without increasing single-bit processing time. Although terfenadine was not different from placebo for any symptom assessed, hydroxyzine produced significant drowsiness ( p = 0.001), dry mouth ( p = 0.022), and irritability ( p = 0.021). During the 5 days of hydroxyzine administration, neither objective nor subjective symptoms demonstrated the development of tolerance. No correlation was found between subjective symptoms and prolongation of reaction times by hydroxyzine, suggesting that side effect symptoms of traditional antihistamines are unreliable predictors of objective performance. Terfenadine provides a promising therapeutic alternative to traditional antihistamines for individuals performing critical tasks.
The dependence of the initial electron-transfer rate on driving force in Rhodobacter sphaeroides reaction centers

The kinetics of the primary electron transfer following excitation of the bacteriochlorophyll dimer (P) to its lowest excited singlet state were determined for a series of reaction center mutants of Rhodobacter sphaeroides that have P/P+ midpoint potentials 44−147 mV below wild type. These strains were capable of photosynthetic growth and had normal bacteriochlorophyll-to-bacteriopheophytin ratios. Decreasing the P/P+ midpoint potential resulted in an increase in the rate constant of initial electron transfer in each of the mutants tested. At room temperature, the fastest electron-transfer time constant observed was 1.8 ps from a mutant with a midpoint potential 127 mV below wild type. The dependence of the rate on driving force in these measurements and in previous measurements of mutants with high P/P+ midpoint potentials at room temperature was fit to a Marcus equation. Wild type was displaced approximately 100 meV from the peak of this curve. This analysis yielded a reorganization energy between 180 a...
In search of wisdom and its blind spots: Catholic reflections on Swami Vivekananda’s 150th birth anniversary

The 150th birth anniversary of Swami Vivekananda is an occasion for interreligious reflection on the enduring significance of his teachings and their potential for reflective engagement. This essay presents and engages select motifs from his four lectures on 'Practical Vedanta', particularly his understandings of sin, solidarity, and the relevance of his thought to the pervasive challenge of religious absolutism in contemporary experience. The essay notes some blind spots or vulnerabilities in his teachings owing to historical context and adopts these as tools to assist in Catholic theological reflection on analogous weaknesses in that tradition.
Characteristics of Radiation Absorption in Metallic Particles

Thermal radiation absorption in metallic particles is an important phenomenon in many contemporary laser-processing techniques, including laser cladding of coating materials and laser cleaning of particulate contaminations. In this work, the Drude free-electron theory and electromagnetic wave theory are utilized to characterize the internal absorption of CO{sub 2} laser radiation in aluminum, chromium, and nickel particles. The results show that metallic particles have unique radiation properties. Radiation absorption in large particles occurs only in a very narrow region of the front particle surface, which results in inefficient radiation absorption. On the other hand, micron and submicron particles can absorb radiation very efficiently due to the strong diffraction effect at the particle surface. For extremely small particles (e.g., nanometer particles), radiation absorption becomes less efficient. The particle absorption efficiency is found to increase with temperature, and this temperature dependence can be determined from those of flat metal surfaces at the normal incidence. 28 refs., 8 figs., 1 tab.
Do Nutrients Influence Bone Health? A Commentary on New Findings in the Field †

Food is always a good topic of conversation and inquiry. Humans require it, the variety of eating patterns spark personal debate, scientific measurement of dietary intakes are fraught with methodical issues, and the often changing (and inconsistent) nutrition messages in the media make for good discussion. The devil is in the detail when it comes to nutrients and the inferences to health beyond food intakes. Indeed, food is often the example when nuances of scientific inference are examined across time periods: “Is dairy good or bad for you?”, “should we consume more or less protein in our diet?” “how much fruit & vegetable is needed?”, or “should salt intake be limited”? Macronutrients (carbohydrates, proteins and fats) as well as micronutrients (minerals and vitamins) are essential for the human body. Intakes of these nutrients have been the topic of bone investigations and patient questions for many years, especially as related to the occurrence of fractures. In this issue of Journal of Bone & Mineral Research, two exciting articles present their findings on first, serum sodium levels, and then, fruit and vegetable intakes, in relation to fracture risk. These topics are highly relevant to clinicians and researchers interested in bone outcomes. Patients are keenly interested in nutrition-related influences upon bone health, both those with positive as well as negative aspects. Examining nutrient intakes in relation to health outcomes is complicated, but can lead to significant risk factor modification as well as influence in food and health decisions, especially in older adults. Defining dietary intakes precisely is a major challenge in both clinical patients and participants of population-based studies as the scientific community continues to search for the long-term effects of dietary intakes. Nutrition studies are common in outcomes of cancer and heart disease, and less so with bone outcomes (with the exception of calcium and vitamin D). Prior to inference of causality, especially for dietary intakes, it is important to first document a significant association with outcomes and across populations.
Schistosoma mansoni: male-biased sex ratios in snails and mice

Adult sex ratios of Schistosoma mansoni, in mice, were shown to be biased toward males (3:1) despite the finding that sex ratios of miracidia were 50:50. The adult male bias was caused by greater male infectivity of miracidia for snails and cercariae for mice. A significantly higher percentage of male miracidia developed to cercarial production in unimiracidial infections (57 male, 34 female), and a significantly higher percentage of male cercariae developed to adulthood in mice (143 male, 79 female worms resulted from 900 male and 900 female cercariae). No significant differences were found between male and female parasites for longevity of miracidia (both sexes, 10 hr) and cercariae (males 21.3 +/- 5.75 hr, females 25.0 +/- 7.02 hr), prepatent periods in snail hosts (male 34 +/- 2.92 days, females 33 +/- 2.36 days), longevity of snail infections (males 96.6 +/- 25.15 days, females 115.2 +/- 82.43 days), and the numbers of cercariae produced per snail lifetime (males 30,751.44 +/- 18,064.33, females 34,083.00 +/- 33,732.82). Present results provide a better understanding of the life cycle of S. mansoni, are of theoretical significance for theories of biased sex ratios (which at present cannot account for the male-biased ratio of S. mansoni), and also suggest that schistosomiasis transmission models assuming a 50:50 sex ratio at all stages of the life cycle should be reassessed.
Virus diseases of orchids in The Netherlands

The most commonly encountered virus diseases in orchid plants in The Netherlands are caused byCymbidium mosaic virus (CyMV) andOdontoglossum ringspot virus (ORSV), either singly or in combination. Data on host ranges are given. De meest algemeen voorkomende virusziekten van orchideeen in Nederland worden veroorzaakt doorCymbidium-mozaiekvirus (CyMV) ofOdontoglossum-kringvlekkenvirus (ORSV) of door een combinatie van beide virussen. Aan de waardplantenreeks van beide virussen wordt uitvoerig aandacht geschonken.
Measuring attentional demand in continuous dual-task performance

Despite its intuitive appeal, the commonly held assumption that there is some general limitation on dual-task performance has been shown to be seriously flawed (Allport 1980; Navon 1984). Central t...
An Exploratory Analysis of Florida Law Enforcement Domestic Violence Policies

The high social cost of domestic violence has caught the attention of lawmakers and criminal justice agency administrators across the country. As public awareness and concern over the incidence of domestic violence has risen, domestic violence legislation has focused on, among other things, the law enforcement response to domestic violence. The purpose of this study is to examine Florida law enforcement agency response to domestic violence by analyzing agency standard operating procedures (SOPs) across measures identified in the Florida Model Policy for Domestic Violence. Utilizing content analysis, the authors identify agency policy mandates including the number of officers responding to the scene, the use of specialized units, availability of victim advocates, and procedures for investigation.
Probabilistic demand models and fragility estimates for offshore wind turbine support structures

Abstract Probabilistic models are developed to predict the deformation, shear and moment demands on offshore wind turbine support structures subject to operational and environmental loadings (i.e., day to day wind, wave and current). An existing deterministic model is corrected by adding a correction term to capture the inherent bias, and model error arising from an inaccurate model form or missing variables. A database of structural responses is used to calibrate the proposed models. The database is obtained from detailed three-dimensional finite element analyses of a set of typical wind turbine systems with different design parameters. The finite element analyses account for the nonlinear soil-structure interaction. The proposed probabilistic demand models provide accurate and unbiased estimates of the demands on the support structure properly accounting for the underlying uncertainties. The models are then used to estimate the fragility of the support structure of wind turbines which is defined as the conditional probability of not meeting specified capacity levels.
Story and Narrative Noticing : Workaholism Autoethnographies

We enter this energetic debate over causes and consequences of workaholism using autoethnography. Our main contribution is to explore when our autoethnographies of workaholism experiences is narrative, and when it is expressive, living story. The difference in narrative is a re-presentation (following representationalism of a sensory remembrance), where as living story is a matter of reflexivity upon the fragile nature of our life world. We began through analysis of workaholism narratives in our own academic lives, and in the movies of popular culture, the influence of a particular meta-narrative – that of the American Dream. We proceed to juxtapose our own living stories in their struggle with those American Dream narratives.
Time-of-flight focusing in a system consisting of electrostatic mirrors with two-dimensional fields

Abstract Time-of-flight properties of a system consisting of successively located mirrors with two-dimensional electrostatic fields having a common plane of symmetry are considered. The conditions for time-of-flight focusing in an angle of divergence of a charged particle beam and in the energy spread are found. The schemes of a time-of-flight spectrometer composed of cylindrical mirrors with external and internal reflection of a beam are calculated.
Assessing the Potential for Reducing Life-Cycle Environmental Impacts through Transit-Oriented Development Infill along Existing Light Rail in Phoenix

There is significant interest in reducing urban growth impacts yet little information exists to comprehensively estimate the energy and air quality tradeoffs. An integrated transportation and land-use life-cycle assessment framework is developed to quantify the long-term impacts from residential infill, using the Phoenix light rail system as a case study. The results show that (1) significant reductions in life-cycle energy use, greenhouse gas emissions, respiratory, and smog impacts are possible; (2) building construction, vehicle manufacturing, and energy feedstock effects are significant; and (3) marginal benefits from reduced automobile use and potential household behavior changes exceed marginal costs from new rail service.
Rate-dependency and hyperactivity: Methylphenidate effects on operant responding

Abstract The two most common treatment for hyperactivity are psychopharmacological regiments and behavior therapy. Although the concurrent use of stimulant medication has been purported to enhance a child's rate of responding under a behavior management program, studies examining the interaction of the two treatments have been unable to confirm this hypothesis. The present investigation sought to examine the effects of differing levels of methylphenidate hydrochloride (Ritalin) upon operant responding with hyperactive children. After an initial drug-free training period, 10 first through fourth grade hyperactive males performed an operant key-pressing task under a mult VR 5 FI 30 sec reinforcement schedule across four randomly determined, double-blind drug conditions (placebo, 5, 10, 15 mg). Only VR responding changed significantly during medication conditions; however, rate-dependent psychostimulant effects were found within both reinforcement schedules. Discrepancies with animal rate-dependency and implications for treatment and future research are discussed. Medication effects on operant responding appear to depend upon the reinforcement schedule and dose employed.
Synchronized oscillations during cooperative feature linking in a cortical model of visual perception

Abstract A neural network model of synchronized oscillator activity in visual cortex is presented in order to account for recent neurophysiological findings that such synchronization may reflect global properties of the stimulus. In these recent experiments, it was reported that synchronization of oscillatory firing responses to moving bar stimuli occurred not only for nearby neurons, but also occurred between neurons separated by several cortical columns (several mm of cortex) when these neurons shared some receptive field preferences specific to the stimuli. These results were obtained not only for single bar stimuli but also across two disconnected, but colinear, bars moving in the same direction. Our model and computer simulations obtain these synchrony results across both single and double bar stimuli. For the double bar case, synchronous oscillations are induced in the region between the bars, but no oscillations are induced in the regions beyond the stimuli. These results were achieved with cellular units that exhibit limit cycle oscillations for a robust range of input values, but which approach an equilibrium state when undriven. Single and double bar synchronization of these oscillators was achieved by different, but formally related, models of preattentive visual boundary segmentation and attentive visual object recognition, as well as nearest-neighbor and randomly coupled models. In preattentive visual segmentation, synchronous oscillations may reflect the binding of local feature detectors into a globally coherent grouping. In object recognition, synchronous oscillations may occur during an attentive resonant state that triggers new learning. These modelling results support earlier theoretical predictions of synchronous visual cortical oscillations and demonstrate the robustness of the mechanisms capable of generating synchrony.
Electron-electron scattering modifications of intervalley transition rates and ultrafast relaxation of hot photoexcited carriers in GaAs

Abstract The femtosecond relaxation of photoexcited carriers in GaAs is investigated by the use of ensemble Monte Carlo calculations coupled with a molecular dynamics approach for the carrier-carrier interaction, to probe various scattering mechanisms and the dynamic screening of hot carriers in semiconductors. At a density for which the GaAs is degenerate (in equilibrium), scattering out of the excitation volume is dominated in the initial tens of femtoseconds by electron-electron scattering, and the lifetime decreases with increasing density. This decrease agrees both in lifetime magnitude and in density dependence with recent experimental measurements. The presence of electron-electron scattering modifies both the population transition rates and the carrier densities in the satellite valleys, primarily by reshaping the energy distribution of carriers in the central valley. Intervalley scattering rates slow by two orders of magnitude as the electronic system cools in the first picosecond. Thus, while intervalley processes do play a role in the initial decay, the same processes play a role in the picosecond-scale luminescence decay. We find that rates, for particular mechanisms of carrier transfer to the satellite valleys, must be estimated carefully since the Γ-L population shift contains a significant fraction of electrons that reach the L valleys by way of the X valleys.
Infusing photonics to increase enrollment in electronics engineering technology

During the last 15 years most of the electronics engineering technology programs across the nation have experienced a constant decline in enrollment. Today's high school students do not seem to consider a career in electronics engineering appealing enough to commit to a field of study in desperate need of new students. They still associate electronics programs with the electronics section of a department store; televisions, stereo systems, DVD and VCR players, and other disposable electronics. While the downward trend continues across the nation, Indian River Community College (IRCC) has been able not only to stop it but to reverse it by attracting a new generation of students. By introducing high school students to new and emerging technologies, their perception of established degrees has changed and their interest has been stimulated. Photonics is one of those technologies capturing students' attention. IRCC, a partner college in the National Center for Optics and Photonics Education (OP-TEC), with the assistance of other colleges like Camden County College which already offers an Associate in Applied Science degree in Photonics, has created a Photonics specialization under the Electronics Engineering Technology program. The targeted marketing of this new specialization has led to an increase in enrollment of 50% in 2005, 80% in 2006, and for 2007 it is projected it to be over 100%. An interesting comparison can be made concerning enrollment at colleges with a full AAS program in photonics like Camden County College and IRCC which uses photonics as an enabling technology. This analysis could lead to a new approach in restructuring engineering technology degrees with the infusion of photonics throughout many technology fields. This presentation will discuss the plan of action that made possible this initiative at Indian River Community College and new program directions at Camden County College, Blackwood, New Jersey.