cssi/SciSciGPT-SciSciNet huggingface dataset:
Light scattering from nonequilibrium interfaces

The asymmetry of the two Brillouin peaks of light scattered from capillary waves on a water-nitrogen interface subject to a temperature gradient has been observed using a Fourier transform heterodyne technique. The local oscillator is frequency-shifted by a few kilohertz to separate the Stokes and anti-Stokes components. Although the sign and the order of magnitude of the effect agree with linear theory, the magnitude of the experimental asymmetry is about one-half of that predicted by linear fluctuating hydrodynamics.
Diagnostic algorithm for the evaluation of hematuria.

Purpose: To present a logical and cost-effective diagnostic approach for primary care physicians to a common symptom, hematuria. Data source: Selected research, review articles, as well as medical textbooks and current government guidelines. Conclusion: Dipstick test and microscopic urinalysis are two common screening tests for hematuria. Once hematuria is discovered, its etiology should be investigated through a comprehensive history, a focused physical examination, laboratory studies, and radiographic imaging. Microscopic urinalysis is simple yet important in distinguishing glomerular from nonglomerular sources of bleeding. Intravenous urography, renal ultrasonography, or computed tomography may be needed to determine the location and characteristics of lesions. Cytoscopy is important in evaluating lower urinary tract lesions. Implications for practice: Hematuria is a frequently encountered symptom that has a broad differential diagnosis ranging from insignificant etiology to potentially life-threatening neoplastic lesions. A systematic method can be useful in efficiently and cost-effectively managing hematuria. Early and appropriate diagnosis of this common symptom results in improved clinical outcomes.
Acute Treatment Options for Spinal Cord Injury

Most treatment options for acute traumatic spinal cord injury (SCI) are directed at minimizing progression of the initial injury and preventing secondary injury. Failure to adhere to certain guiding principles can be detrimental to the long-term neurologic and functional outcome of these patients. Therapy for the hyperacute phase of traumatic SCI focuses on stabilizing vital signs and follows the Advanced Trauma Life Support (ATLS) algorithm for ensuring stability of airway, breathing and circulation, and disability (neurologic evaluation)—with spinal stabilization—and exposure. Spinal stabilization, with cervical collars and long backboards, is used to prevent movement of a potentially unstable spinal column injury to prevent further injury to the spinal cord and nerve roots, especially during prehospital transport. Surgery to stabilize the spine is undertaken after life-threatening injuries (hemorrhage, evacuation of intracranial hemorrhage, acute vascular compromise) are addressed. Intensive care unit (ICU) admission is to be considered for all patients with high SCI or hemodynamic instability, as well as those with other injuries that independently warrant ICU admission. Avoidance of hypotension and hypoxia may minimize secondary neurologic injury. Elevating the mean arterial pressure above 85 mmHg for 7 days should be considered, to allow for spinal cord perfusion. The use of intravenous steroids (methylprednisolone) is controversial. Early tracheostomy in patients with lesions above C5 may reduce the number of ventilator days and the incidence of ventilator-associated pneumonia. Select patients may benefit from the placement of a diaphragmatic pacer. Aggressive measures, including CoughAssist and Intermittent Positive Pressure Breaths (IPPB), should be used to maintain lung recruitment and aid in the mobilization of secretions. Some patients with high SCI who are dependent on mechanical ventilation can eventually be liberated from the ventilator with consistent efforts from both the patient and the caregiver, along with some patience. Intermittent catheterization by the patient or a caregiver may be associated with a lower incidence of urinary tract infections, compared with an in-dwelling urinary catheter. Early mobilization of patients and a multidisciplinary approach (including respiratory therapists, nutritional experts, physical therapists, and occupational therapists) can streamline care and may improve long-term outcomes. A number of investigational drugs and therapies offer hope of neurologic recovery for some patients.
Transbilayer phospholipid movement and the clearance of apoptotic cells

When lymphocytes (and other cells) die by apoptosis, they orchestrate their own orderly removal by macrophages, and thereby prevent the inflammation that would otherwise attend cell lysis. As part of their demise, apoptotic cells disrupt the normal asymmetric distribution of phospholipids across their plasma membranes, an asymmetry normally maintained by an aminophospholipid translocase. This disruption of asymmetry, mediated by an activity known as the scramblase, generates ligands on the cell surface that trigger phagocytosis of the dying cell before lysis can occur. This crucial alteration of the plasma membrane is not dependent on caspase-mediated proteolysis, but quite unexpectedly, it is required both on the apoptotic target cell and on the phagocyte that engulfs it. At least in the phagocyte, this rearrangement may depend on the activity of an ABC ATPase, termed ABC1 in mammals and ced-7 in C. elegans.
Supernova neutrino detection

Abstract Detecting neutrinos is the key to understanding core-collapse supernovae, but this is notoriously difficult due to the small interaction cross section of neutrinos and the low frequency of supernovae in galaxies. The revolutionary implications of the detection of about 20 neutrinos from SN 1987A tell us that this quest is worthy. However, there is the sobering fact that there have been no other detections, before or since. Now, after decades of effort and patience, we have good reasons to anticipate that detecting supernova neutrinos again is within reach, in particular for the Diffuse Supernova Neutrino Background (DSNB). A first detection of the DSNB in a short time is possible if Super-Kamiokande is upgraded with the proposed modification of dissolved gadolinium to allow neutron tagging. Longer-term, a comprehensive understanding of core-collapse supernovae will require something like the possible Hyper-Kamiokande detector, eventually also with dissolved gadolinium. This systematic path towards increasing sensitivity will surely lead to further revolutionary discoveries in astrophysics.
Chiral catalyst enhancement of diastereocontrol for OH insertion reactions of styryl- and phenyldiazoacetate esters of pantolactone

Abstract The chiral dirhodium(II) catalyst Rh2(MEAZ)4 increases diastereocontrol for intermolecular OH insertion reactions of diazo esters having a chiral auxiliary over that achieved with Rh2(OAc)4.
Willingness to pay for reliable supplies of safe drinking water in Guatemala: A referendum contingent valuation study

Unreliability of water systems has become a major concern in many developing countries. A referendum-format contingent valuation (CV) survey was implemented to investigate household preferences, in monetary terms, for improved water services in the small town of San Lorenzo, Guatemala. A random sample of 500 households report that they currently adopt a variety of averting measures (e.g. in-home water storage and treatment) to cope with service interruptions and low water quality. Findings also indicate that households are willing to pay an increase of more than 200% in their water bill for reliable supplies of safe drinking water.
Cholera--modern pandemic disease of ancient lineage.

Cholera has affected humans for at least a millennium and persists as a major cause of illness and death worldwide, with recent epidemics in Zimbabwe (2008–2009) and Haiti (2010). Clinically, evidence exists of increasing severity of disease linked with emergence of atypical Vibrio cholerae organisms that have incorporated genetic material from classical biotype strains into an El Tor biotype background. A key element in transmission may be a recently recognized hyperinfectious phase, which persists for hours after passage in diarrheal feces. We propose a model of transmission in which environmental triggers (such as temperature) lead to increases in V. cholerae in environmental reservoirs, with spillover into human populations. However, once the microorganism is introduced into a human population, transmission occurs primary by “fast” transmission from person to person (taking advantage of the hyperinfectious state), without returning to the aquatic environment.
Time-dependent diffusion coefficients in periodic porous materials.

We derive an approximate solution for the Laplace transform of the time-dependent diffusion coefficient, D(t), of a molecule diffusing in a periodic porous material. In our model, the material is represented by a simple cubic lattice of identical cubic cavities filled with a solvent and connected by small circular apertures in otherwise reflecting cavity walls, the thickness of which can be neglected. The solution describes the decrease of D(t) from its initial value, D(0) = D, where D is the diffusion constant in the free solvent, to its asymptotic value, D(∞) = Deff, which is much smaller than D. A simple heuristic formula for the mean-squared displacement of the diffusing molecule is suggested. The theoretically predicted results are in good agreement with the data obtained from Brownian dynamics simulations.
Sperm transport and storage and its relation to the annual sexual cycle of the female red-sided garter snake, Thamnophis sirtalis parietalis.

Female red-sided garter snakes (Thamnophis sirtalis parietalis) store sperm from both late-summer and spring matings. Before winter dormancy, sperm are stored in specialized furrows in the vaginal portion of the oviduct, 3-6 cm anterior to the vent. After 6 weeks in dormancy, the epithelial cells lining this vaginal region hypertrophy and stain strongly with periodic acid-Schiff (PAS). This PAS+ epithelial border sloughs and associates with sperm. These aggregations of PAS+ material, which will be referred to as carrier matrices, move anteriorly through the oviduct. After 20 weeks in dormancy, most sperm are found in specialized infundibular storage regions. Spring mating induces a rapid degeneration of winter-stored sperm. Stored sperm are evacuated from infundibular storage receptacles within 6 hours after mating. Yet sperm from the spring mating are not evident in the oviduct until 24 hours after mating. Carrier matrices begin to form at this time. At 48 hours after mating, sperm, often associated with carrier matrices, appear in the infundibulum. At 40 days after mating, most sperm have moved into infundibular storage receptacles. Evidence suggests that carrier matrices not only facilitate the transport of sperm anteriorly from vaginal to infundibular regions, but also function as nutritional stores.
Factors Influencing the Distribution of Lindane and Other Hexachlorocyclohexanes in the Environment

This review examines the potential for γ-hexachlorocyclohexane (HCH) to be transformed into other isomers of HCH. HCH residues are among the most widely distributed and frequently detected organochlorine contaminants in the environment. The potential environmental and human health risks associated with these residues have prompted Canada, the United States, and Mexico to consider the development of a North American Regional Action Plan (NARAP) to assess and mitigate HCH pollution. More information on the propensity of γ-HCH to transform into other isomers is essential to the development of an effective regional management program. The high relative concentrations of α-HCH in the Arctic suggest that γ-HCH may be transformed into other isomers in the environment. Laboratory studies show that significant photoisomerization of γ-HCH to α-HCH is possible. However, field studies do not find evidence for significant isomerization of γ-HCH, and recent environmental samples suggest that α-HCH residues are declinin...
Flow Structure in a Radial Flow Pumping System Using High-Image-Density Particle Image Velocimetry

Use of high-image-density particle image velocimetry (PIV) allows characterization of the instantaneous structure of wake and wake-blade interactions in a simulated rotating machine. The distribution of vorticity over an entire plane within the pumping system is related to the instantaneous pressure source terms in the wake of the impeller. Comparison of instantaneous and ensemble-averaged vorticity contours shows that limited ensemble-averaging can produce a substantial reduction in vorticity levels associated with the instantaneous pressure source terms. When the wake from the impeller interacts with a stationary diffuser blade, the instantaneous processes of flow separation and reattachment can be effectively characterized using combinations of instantaneous streamline patterns and contours of constant vorticity. Moreover, active control of the inflow into the pumping system allows substantial modification of these vorticity distributions.
Disposition kinetics of ethambutol in man

Six normal adult volunteers were administered 15 mg/kg of ethambutol (EMB) by a constant-rate 1-hr infusion. Plasma and urine samples were collected up to 24 and 72 hr, respectively. Peak plasma levels following the 1-hr infusion ranged from 11.6 to 15.4 μg/ml. Subsequent postinfusion EMB levels exhibited multiphasic decay. In the 12-hr period following infusion, EMB levels showed biexponential decay. However, 24-hr plasma levels in all subjects were observed to be higher than those predicted using a two-compartment body model. The α phase in these subjects had a mean half-life of 8.6 min while the half-life of the β phase ranged from 2.5 to 3.6 hr (mean 3.1). The half-life of the γ phase estimated from plasma data points between 12 and 24 hr averaged 11.2±3.6 hr. A terminal γt1/2 of 15.4±1.7 hr was calculated from 12–72 hr urine data. The mean value for the steady-state volume of distribution using a noncompartmental method was 3.89 liters/kg. Plasma EMB clearance ranged from 7.47 to 9.87 ml/min/kg (mean 8.57). The fraction of the dose eliminated unchanged varied from 0.75 to 0.84 (mean 0.79). Renal clearance ranged from 5.93 to 8.45 ml/min/kg (mean 6.81), indicating active tubular secretion.
ASSESSMENT OF THE EXTENT OF CONSISTENCY LOSS IN SEMILIQUID FOODS BY COMPRESSION AND SHEAR

The consistency of commercial mayonnaise, mustard and tomato paste samples was assessed by squeezing flow before and after compression or stirring, by hand and with a domestic blender which caused intensive shearing. The specimens before and after these treatments were squeezed between Teflon® coated parallel plates mounted on an Instron UTM model 5542 to a final height of 0. 8 mm and had been let to relax before the crosshead was withdrawn. Their consistency was assessed in terms of their apparent stress at three heights, and after relaxation for I and 2 min at 0.8 mm height. Compression of the specimen prior to its testing (1-3 times) has very little effect on the specimen's consistency which supports the view that there was little friction between the Teflon® coated plates and the samples. Shearing caused measurable loss of consistency in the mustard and tomato paste which was not fully restored even after three hours. The sheared mayonnaise restored much of its consistency after about an hour as judged by the apparent stress at a given height, and almost fully recovered it if judged by the apparent residual stress after relaxation.
In Vitro Mesenchymal Trilineage Differentiation and Extracellular Matrix Production by Adipose and Bone Marrow Derived Adult Equine Multipotent Stromal Cells on a Collagen Scaffold

Directed differentiation of adult multipotent stromal cells (MSC) is critical for effective treatment strategies. This study was designed to evaluate the capability of equine MSC from bone marrow (BMSC) and adipose tissue (ASC) on a type I collagen (COLI) scaffold to undergo chondrogenic, osteogenic and adipogenic differentiation and form extracellular matrix (ECM) in vitro. Following determination of surface antigen expression, MSC were loaded into scaffolds in a perfusion bioreactor and loading efficiency was quantified. Cell-scaffold constructs were assessed after loading and 7, 14 and 21 days of culture in stromal or induction medium. Cell number was determined with DNA content, cell viability and spatial uniformity with confocal laser microscopy and cell phenotype and matrix production with light and scanning electron microscopy and mRNA levels. The MSC were positive for CD29 (>90 %), CD44 (>99 %), and CD105 (>60 %). Loading efficiencies were >70 %. The ASC and BMSC cell numbers on scaffolds were affected by culture in induction medium differently. Viable cells remained uniformly distributed in scaffolds for up to 21 days and could be directed to differentiate or to maintain an MSC phenotype. Micro- and ultrastructure showed lineage-specific cell and ECM changes. Lineage-specific mRNA levels differed between ASC and BMSC with induction and changed with time. Based on these results, equine ASC and BMSC differentiate into chondrogenic, osteogenic and adipogenic lineages and form ECM similarly on COLI scaffolds. The collected data supports the potential for equine MSC-COLI constructs to support diverse equine tissue formation for controlled biological studies.
Factors Influencing the Development of Perfectionism in Gifted College Students

This study is part of a larger research investigation of perfectionism in gifted college students. Employing a qualitative interview design, this study examined factors contributing to the development of two dimensions of perfectionism, socially prescribed and self-oriented, in gifted college students. Findings indicated that exposure to parental perfectionism and an authoritarian parenting style led to the perception of stringent expectations, self-worth tied to achievement, and a fear of disappointing others, which collectively influenced the development of socially prescribed perfectionism. Factors contributing to the development of self-oriented perfection included mastery of early academic experiences without effort, no previous experience with academic failure, and modeling of parental perfectionism. Implications for future research and recommendations for parents and educators of gifted children are suggested.
A Dynamical Successor to Modernism and Postmodernism.

The author introduces an emerging worldview that could affect counseling concepts and methods greatly in the relatively near future. The worldview, dynamicalism, incorporates essential features of modernism and postmodernism. It also incorporates cutting-edge concepts from physics and philosophy. The synthesis of these ideas provides a conceptual basis for thinking about and conducting counseling in new ways.
A principal component analysis of SO2−4 precipitation concentrations over the eastern United States

Abstract The spatial and temporal variability of SO 4 2− concentrations in precipitation over the eastern U.S. during the period 1981–1986 was examined through the use of principal component analysis. Application of Kaiser's Varimax orthogonal rotation led to the delineation of seven contiguous subregions, each displaying statistically unique SO 4 2− concentration characteristics. These seven statistically significant modes of variability, which together accounted for 74.2% of the total variance, corresponded well with major SO x emission patterns. Examination of the time series associated with each subregion revealed a general seasonality in which periods of high concentrations are more likely during the summer, while periods of low concentration are more likely during the winter. This seasonal cycle, however, was more prevalent in those subregions which contained few major emissions, and was less prevalent and often obscured by perturbations in those subregions which contained major emissions.
Transition State Stabilization and α-Amino Carbon Acidity in Alanine Racemase

Combined QM/MM simulations have been carried out to investigate the origin of the carbon acidity enhancement in the alanine racemization reaction catalyzed by alanine racemase (AlaR). The present studies show that enhancement of carbon acidity of α-amino acids by cofactor pyridoxal 5‘-phosphate, PLP, with an unusual, unprotonated pyridine is due to solvation effects, in contrast to the intrinsic electron-withdrawing stabilization by the pyridinium ion to form a quinonoid intermediate. Alanine racemase further lowers the α-proton acidity and provides an overall 14−17 kcal/mol transition state stabilization. Our computational results are consistent with the hypothesis that the use of the unusual form of PLP cofactor in AlaR is to raise the free energy of the intermediate, thereby increasing the reprotonation rate and enhancing the enzyme selectivity for racemization.
Imaging the Permeability Pore Transition in Single Mitochondria

In mitochondria the opening of a large proteinaceous pore, the "mitochondrial permeability transition pore" (MTP), is known to occur under conditions of oxidative stress and matrix calcium overload. MTP opening and the resulting cellular energy deprivation have been implicated in processes such as hypoxic cell damage, apoptosis, and neuronal excitotoxicity. Membrane potential (delta psi(m)) in single isolated heart mitochondria was measured by confocal microscopy with a voltage-sensitive fluorescent dye. Measurements in mitochondrial populations revealed a gradual loss of delta psi(m) due to the light-induced generation of free radicals. In contrast, the depolarization in individual mitochondria was fast, sometimes causing marked oscillations of delta psi(m). Rapid depolarizations were accompanied by an increased permeability of the inner mitochondrial membrane to matrix-entrapped calcein (approximately 620 Da), indicating the opening of a large membrane pore. The MTP inhibitor cyclosporin A significantly stabilized delta psi(m) in single mitochondria, thereby slowing the voltage decay in averaged recordings. We conclude that the spontaneous depolarizations were caused by repeated stochastic openings and closings of the transition pore. The data demonstrate a much more dynamic regulation of membrane permeability at the level of a single organelle than predicted from ensemble behavior of mitochondrial populations.
Indications for Lower Urinary Tract Reconstruction in Women After Cystectomy for Bladder Cancer: A Pathological Review of Female Cystectomy Specimens

AbstractPurpose: In an attempt to identify women who may be appropriate candidates for orthotopic lower urinary tract reconstruction, archival cystectomy specimens from female patients undergoing cystectomy for primary bladder cancer were reviewed. These pathological findings should provide a better understanding of tumor involvement at the bladder neck (vesicourethral junction) and urethra in women with transitional cell carcinoma of the bladder.Materials and Methods: Cystectomy specimens of 67 consecutive women undergoing surgery for biopsy proved transitional cell carcinoma of the bladder between July 1982 and July 1990 were pathologically reviewed.Results: Histological evidence of tumor (carcinoma in situ or gross carcinoma) involving the urethra was present in 9 patients (13 percent). Tumor was confined to the proximal and mid urethra, and the distal urethra was not involved. All patients with carcinoma involving the urethra had concomitant evidence of carcinoma involving the bladder neck. A total of...
Conceptual citation differences in science, technology, and social sciences literature

Abstract This study examined three disciplines and the literature to determine if there were any differences in conceptual referencing patterns. Physics, engineering, and sociology were examined using the actual literature of the disciplines for the year 1984. Samples were drawn from major abstracting and indexing services. A Dunn planned comparison approach was used to test for differences. The results of the testing indicated that physics, engineering, and sociology all differ in terms of conceptual references. Two sub-tests were performed on the data. Total number of references were examined, indicating no difference between physics and sociology, but distinct differences between physics and engineering and between sociology and engineering. The second sub-test examined the number of references to literature within a 5-year span of publication. This second test indicated differences between physics and sociology and between physics and engineering, but no difference between sociology and engineering. Suggestions for further study are offered.
SIMTOOLS: a software tool kit for discrete event simulation in Pascal

SIMTOOLS is a collection of procedures and functions that allow discrete event simulation programs to be easily developed in Pascal. The package, which implements the event view, has pro cedures for creating and deleting entities, managing lists or queues, event scheduling and sequencing, system tracing and data collection. It is useful for any model-building effort, but especially those which do not fall neatly into the class of queu ing networks where specialized simulation software is available. The advantages of such an approach include the ability to apply top-down design, self-documentation, portability and the fact that the only development software required is the Pascal compiler.
All-Time Releases of Mercury to the Atmosphere from Human Activities

Understanding the biogeochemical cycling of mercury is critical for explaining the presence of mercury in remote regions of the world, such as the Arctic and the Himalayas, as well as local concentrations. While we have good knowledge of present-day fluxes of mercury to the atmosphere, we have little knowledge of what emission levels were like in the past. Here we develop a trend of anthropogenic emissions of mercury to the atmosphere from 1850 to 2008-for which relatively complete data are available-and supplement that trend with an estimate of anthropogenic emissions prior to 1850. Global mercury emissions peaked in 1890 at 2600 Mg yr(-1), fell to 700-800 Mg yr(-1) in the interwar years, then rose steadily after 1950 to present-day levels of 2000 Mg yr(-1). Our estimate for total mercury emissions from human activities over all time is 350 Gg, of which 39% was emitted before 1850 and 61% after 1850. Using an eight-compartment global box-model of mercury biogeochemical cycling, we show that these emission trends successfully reproduce present-day atmospheric enrichment in mercury.
Calculation of infrared band intensities of various chlorinated methanes

Abstract Infrared band intensities of three molecular species CHCl 3 , CDCl 3 and CCl 4 , were measured in the vapour phase and the band intensity data of thirteen kinds of various chlorinated methanes, from methane to carbon tetrachloride, have been interpreted by means of as few as possible common intensity parameters. The parameters have been determined by using the least squares method from the observed data on the basis of the valence-optical theory. As a result, it has been proved that for almost all electro-optical parameters, it is possible to determine values which are commonly applicable to all chlorinated methane molecules, but for μ CH and ∂μ CH / ∂ r CH , it is not possible to find commonly applicable values.
Can the client with chronic schizophrenia consent to nursing research

As nurses enter the field of research and design nursing studies, an awareness of the standards of informed consent becomes imperative. Informed consent is commonly considered to include providing the subject with adequate and understandable information regarding therapeutic and experimental procedures and ensuring subjects' competent understanding of this information. Providing information about a procedure is relatively easy but evaluating competency is often difficult. It is especially difficult with the subject who may suffer cognitive impairment, e.g. schizophrenia. Clients with schizophrenia have traditionally been a disenfranchised group. It is important they do not become neglected in nursing research because of concerns about competency to provide informed consent. This paper provides a discussion of the historical development of informed consent. Additionally, the legal standards of informed consent and the legally accepted standards of competency are elucidated. Four issues are considered: (a) evidencing a choice, (b) factual understanding of the issues, (c) rational manipulation of information, and (d) appreciation of the nature of the situation. These issues are related to a nursing research study designed by the senior author to test the beliefs of subjects with chronic schizophrenia.
The effects of heavy metal cations and sulfhydryl reagents on degranulation from digitonin-permeabilized neutrophils

Digitonin-permeabilized neutrophils were exposed to micromolar levels of a variety of heavy metal cations and sulfhydryl oxidants to gain insight into the potential biochemical mechanisms underlying neutrophil degranulation. The results from this study suggest that the oxidation of intracellular sulfhydryl groups may play a role in neutrophil signal transduction. Evidence to support this conclusion is based on the observation that cupric phenanthroline and Cu2+/cysteine, agents reported to induce disulfide bond formation, evoke significant granule enzyme release when presented to permeabilized neutrophils. The stimulatory actions of these compounds occur in the absence of Ca2+ and are blocked by the sulfhydryl reducing agent, dithiothreitol. In addition, we observed marked potentiation of Ca2+-induced secretion by potentially physiological levels of Ni2+. Although we are unaware of any Ni2+-requiring enzymes in eukaryotic cells that are likely to be pertinent to degranulation, the ability of this divalent metal cation to lower the Ca2+ requirements for granule secretion suggests that it may play an important regulatory role in Ca2+-dependent processes. Finally, we observed significant granule release when permeabilized neutrophils were exposed to the heavy metal cations, Hg2+ and Ag+. The apparent stimulatory actions of these metals were the result of lysis rather than degranulation. Thus, the ability of these metals to lyse intracellular organelles such as lysosomal granules may contribute to their toxicological properties.
In vitro production of ultraviolet-absorbing lipids by hog adrenal homogenates.

A technique by which corticoid biosynthesis proceeds with hog adrenal homogenates is described. The amount of UVAL released into the incubation medium is greater than, but proportional to, the amount of blue tetrazolium reacting corticoids produced. A TPNH generating system under aerobic conditions is required for steroid production. Substitution of N2 for O2 in the incubation atmosphere or deletion of TPN or G6P from the medium resulted in a complete cessation of corticoid production. G6PD was present in sufficient quantities in the adrenal tissue, and it was found that the addition of exogenous enzyme was not required. Chromatographing the methylene dichloride extract of the incubation medium revealed that in the presence of TPNH under aerobic conditions the major products were BT reacting corticoids, that progesterone did not accumulate, and that a sharp drop in adrenal free cholesterol content occurred. In the absence of TPNH, pregnenolone stimulated the formation of UVAL, of which 25 to 35% was tenta...
Striatal concentrations of vesicular monoamine transporters are identical in MPTP-sensitive (C57BL/6) and -insensitive (CD-1) mouse strains

Abstract Sensitivity to the neurotoxic actions of 1-methyl-4-pheny1-1,2,3,6-tetrahydropyridine (MPTP) varies greatly among strains of mice. The numbers of vesicular monoamine transporters was examined in various brain regions of MPTP-sensitive (C57BL/6) and MPTP-insensitive (CD-1) mouse strains. In vivo radioligand binding to the vesicular monoamine transporter was studied using [11C]methoxytetrabenazine, and in vitro Bmax values determined using [3H]dihydrotetrabenazine autoradiography. Using either technique, no significant differences between the two strains were seen in the striatal binding of these radioligands to the vesicular monoamine transporter. The in vivo binding of radioligands to this transporter in the striatum was also not gender dependent. The relative resistance of CD-1 mice to the neurotoxic effects of peripheral MPTP administration thus does not appear to be a result of enhanced protection by higher levels of vesicular storage in dopaminergic neurons of the striatum.
Particle annihilation in cold dark matter micropancakes

Cold primordial particle dark matter forms with a distribution in six-dimensional phase space closely approximating a three-dimensional sheet. Folds in the mapping of this sheet onto configuration space create ubiquitous sheetlike caustics (``micropancakes''). A typical weakly interacting massive particle dark matter halo has many micropancakes, each with a scale comparable to the halo itself, a width about ${10}^{\ensuremath{-}8}$ of the halo size and a typical maximum density up to about ${10}^{4}$ times the halo mean. It is suggested here that the total annihilation rate of dark matter particles is dominated by particles close to these micropancakes, so radiation is emitted predominantly from highly contorted two-dimensional surfaces rather than a filled volume. The total annihilation rate of particles is about a factor of 5 higher than predicted from N-body simulations, which cannot resolve these features. Micropancakes also produce sharp line discontinuities in the surface brightness of annihilation radiation.
Enhanced Born charge and proximity to ferroelectricity in thallium halides

Electronic-structure and lattice-dynamics calculations on thallium halides show that the Born effective charges in these compounds are more than twice larger than the nominal ionic charges. This is a result of cross-band-gap hybridization between $\text{Tl}\text{ }p$ and halogen-$p$ states. The large Born charges cause giant splitting between longitudinal and transverse-optic phonon modes, bringing the lattice close to ferroelectric instability. Our calculations indeed show that cubic TlBr develops ferroelectric instabilities upon lattice expansion starting at 2%. It is remarkable that the apparently ionic thallium halides with a simple cubic CsCl structure and large differences in electronegativity between cations and anions can be very close to ferroelectricity. This can lead to effective screening of defects and impurities that would otherwise be strong carrier traps and may therefore contribute to the relatively good carrier transport properties in TlBr radiation detectors.
Relation between damping, current-induced torques, and wall resistance for domain walls in magnetic nanowires

We show that each mechanism of the Gilbert damping of wall motion corresponds to a current-induced drive torque on the domain wall, based on the same electron processes. For example, the damping theory of Heinrich, Fraitova, and Kambersky is directly related to the theory of (nonadiabatic) drive torques by Zhang and Li. Using momentum conservation, this relation is extended to the wall resistance. This leads to a classification of most existing electron theories of damping and drive torques, and of wall resistance, into only three different kinds. In all cases, the drive torque is derived from the damping torque by replacing the wall speed by an electron drift speed $\ensuremath{\simeq}{R}_{0}j$, where ${R}_{0}$ is the ordinary Hall constant and $j$ the current density. This drift speed differs from the one which appears in existing theories of adiabatic spin-transfer torques on a wall. Using the present ideas, mechanisms for drive torques and wall resistance have been invented.
Effect of Substrate Temperature on Properties of Nano-Scale Functionally Graded Calcium Phosphate Coatings

The effect of substrate temperature and processing parameters on microstructure and crystallinity of calcium phosphate coatings deposited on heated substrates in an Ion Beam Assisted Deposition (IBAD) system are being studied. The experimental procedures include mechanical testing and film thickness measurements using bonding strength and profilometery. Cross-sectional scanning transmission electron microscopy (STEM) with energy dispersive X-ray spectroscopy (EDX) through the thickness of the film as well as scanning electron microscopy (SEM) with EDX at the top surface of the film was performed to evaluate the microstructure of the film. The coating crystallinity was studied through X-ray diffraction (XRD). The information gained from current analysis on the set temperature coatings will be used to refine the processing techniques of the Functionally Graded Hydroxyapatite (FGHA) coating.Copyright © 2006 by ASME
Hydride transfer reactions involving saturated hydrocarbons and CCl3+, CCl2H+, CCl2F+, CF2Cl+, CF2H+, CF3+, NO+, C2H5+, sec-C3H7+ and t-C4H9+☆

Abstract The compounds CCl4, CCl3H, CCl3F, CCl2F2, CF3H, CF4, NO, C2H6, neo-C5H12, and C3H8 were ionized by low energy electrons in a pulsed ion cyclotron resonance spectrometer to produce CCl3+, CCl2H+, CCl2F+, CF2Cl+, CF2H+, CF3+, NO+, C2H5+, t-C4H9+, and sec-C3H7+ ions, respectively. In these pure compounds, the respective ions formed are all unreactive, and can be trapped with essentially no loss in the ICR analyzer cell for up to 0.2 s after their formation, at a pressure of 10−7–10−5 torr. When alkanes or cycloalkanes are added to these compounds, the predominant ions formed in each case undergo a hydride transfer reaction with the added alkane. This is the only reaction channel: A+ + RH → AH + R+ (where A+ is the initial ion formed and RH is the added alkane or cycloalkane). By following the abundances of the reactant ions as a function of time in these dilute mixtures, approximately one hundred rate coefficients of hydride transfer reactions of thermal ions (in the range 10−12–10−9 cm3 molecule−1 s−1) have been determined. For several of these ions, it is demonstrated that even when reaction is very exothermic at every site in the molecule the reacting ion exhibits positional selectivity. Detailed examination of the reaction probabilities for these ions reacting with alkanes of different chain lengths and structures leads to the conclusion that the rates of hydride transfer reactions depend in part on the exothermicity of the reaction and in part on the lifetime of the ion-molecule complex. For large reactant ions such as t-C4H9+, steric effects may also play a role. The product ions formed in these hydride transfer reactions undergo further fragmentation to an extent which depends on the exothermicity of the reaction; the most important fragmentation paths correspond to loss of C2C4 olefins from the product alkyl ions.
Quantitative MR imaging of children with sickle cell disease: Striking T1 elevation in the thalamus

Nineteen patients with sickle cell disease (SCD) were examined with conventional MR imaging (cMRI), including T1- and T2-weighted sequences and MR angiography (MRA). qMRI mapping of T1 was also done using a precise and accurate inversion-recovery (PAIR) technique optimized and validated previously. In addition, 21 healthy African-American control subjects had the qMRI examination. Nonparametric Kruskal-Wallis analysis of variance of control subjects, of SCD patients without stroke, and of SCD patients with stroke showed that T1 increased with disease severity in the thalamus, frontal white matter, genu, and occipital white matter. T1 was significantly longer in SCD patients without stroke (n = 13) than in control subjects (n = 21) in the thalamus and frontal white matter. In addition, T1 values were significantly longer in SCD patients with stroke than in patients without stroke in the genu and frontal white matter. Abnormality of the thalamus was identified by qMRI in a substantial fraction of patients read as normal by both cMRI and MRA, suggesting that it may be possible to use T1 elevation to identify a subset of patients with SCD who are at elevated risk for stroke.
Golgi Localization of Carbohydrate Sulfotransferases Is a Determinant of L-selectin Ligand Biosynthesis

Sulfation of endothelial glycoproteins by the sulfotransferase GlcNAc6ST-2 is a regulatory modification that promotes binding of the leukocyte adhesion molecule L-selectin. GlcNAc6ST-2 is a member of a family of related enzymes that act on similar carbohydrate substrates in vitro but discrete glycoproteins in vivo. We demonstrate that GlcNAc6ST-1, -2, and -3 have distinct Golgi distributions, with GlcNAc6ST-1 confined to the trans-Golgi network, GlcNAc6ST-3 confined to the early secretory pathway, and GlcNAc6ST-2 distributed throughout the Golgi. Their localization was correlated with preferred activity on either N-linked or O-linked glycoproteins. A chimera comprising the localization domain of GlcNAc6ST-1 fused to the catalytic domain of GlcNAc6ST-2 was confined to the trans-Golgi network and adopted the substrate preference of GlcNAc6ST-1. We propose a model in which Golgi enzyme localization and competition orchestrate the biosynthesis of L-selectin ligands.
Savulescu’s objections to the future of value argument

This essay is a response to Julian Savulescu’s objections to the future of value argument for the immorality of abortion published in the Journal of Medical Ethics , June 2002. Firstly, Savulescu’s claim that the future of value argument has implausible implications is considered. The author argues that the argument does not have these implications. Secondly, properties which, according to Savulescu, could underwrite the wrongness of killing and that are acquired only after implantation, are considered. It is argued that none of these properties is an adequate basis for the distinction between wrongful and permissible killing.
Transrectal ultrasound-guided biopsy causes hematogenous dissemination of prostate cells as determined by RT-PCR

Objectives. To determine if transrectal ultrasound-guided (TRUS) prostate biopsy causes dissemination of prostate cells into the circulation as assessed by reverse transcriptase-polymerase chain reaction (RT-PCR) targeted against prostate-specific antigen (PSA) mRNA. Methods. RT-PCR PSA analysis was performed before and after prostatic invasive manipulations in 50 men. The cases consisted of 47 patients with TRUS and 3 with transurethral resection of the prostate (TURP). Peripheral venous blood (8 mL) was drawn before and within 60 minutes after the procedure. Total RNA was extracted from fractionated blood, and RNA/cDNA quality was assured and normalized with beta-actin RT-PCR analysis. The PSA primers hybridize exons 3 and 5, yielding a 254-basepair PCR product. The assay detects one LNCaP cell in a background of 100 million lymphoid cells and a single copy of PSA cDNA on an ethidium bromide gel. Results. Among the 47 TRUS cases, 43 specimens were evaluable. Forty-two cases were negative before biopsy; among these patients, 4 cases (9.5%) converted to a positive RT-PCR PSA result. Both benign and malignant TRUS biopsies were capable of producing a positive RT-PCR PSA signal implicating iatrogenic dissemination of cells. All three TURP cases converted from a negative to a highly intense positive signal. Conclusions. We conclude that a positive RT-PCR PSA signal may result from release of prostate cells into the peripheral circulation after a TRUS biopsy and TURP. TURP causes greater dissemination than TRUS. Based on these preliminary data, we recommend that future molecular staging studies should be based on blood specimens drawn before performance of TRUS biopsy. This may be an important mechanism of prostate cancer dissemination meriting further investigations.
Low-cost analog signal generation using a pulse-density modulated digital ATE channel

This paper proposes using a digital ATE channel to generate a pulse-density modulated bit stream, which is then filtered on the DUT-board to form an arbitrary analog waveform at very low cost. Experiments have shown a noise density of -121 dBc in 1 Hz and a spurious free dynamic range (SFDR) of 73 dB, which make the approach suitable for medium performance applications. A per-pin ATE architecture where bit frequency and pattern sequence can be selected for a single pin is particularly well suited. Low-jitter digital channels and symmetrical pulses lead to good analog signal quality. The proposed low-cost test resource contributes to lower cost of test by enabling more parallel test.
On experiments with a transport protocol for pervasive computing environments

It is well-known that TCP performs poorly in a wireless environment. This paper presents an empirical performance analysis of TCP on cellular digital packet data, Bluetooth and wireless LAN. We also present CentaurusComm, a message based transport protocol designed to perform well in low bandwidth networks and resource poor devices. In particular, CentaurusComm is optimized to handle data exchanges consisting of short message sizes. The application used to perform all the experiments is typical of common applications that would use these protocols and network technologies. Typical mobile devices used in the experiments included Palm Pilots. We present results of performance evaluation of TCP and CentaurusComm on different wireless technologies.
10 networking papers: recommended reading

Christophe Diot, the Editor-in-Chief of this ACM Computer Communication Review, and I were recently discussing our impression that we often seem to be drowning in a sea of papers – there are more interesting papers being published than one could read in a lifetime. We discussed the idea of a series of occasional contributions to CCR by members of our technical community on networking papers that they would recommend to others. Certainly, I’d like to hear what my colleagues would recommend as interesting, important, or thought-provoking papers in our field! Christophe asked me to kickoff this series, and I have taken him up on his offer.
Regulation of local populations of a coral reef fish via joint effects of density- and number-dependent mortality

Density-dependent mortality can regulate local populations - effectively minimizing the likelihood of lo- cal extinctions and unchecked population growth. It is considered particularly important for many marine reef organisms with demographically open populations that lack potential regulatory mechanisms tied to local repro- duction. While density-dependent mortality has been doc- umented frequently for reef fishes, few studies have ex- plored how the strength of density-dependence varies with density, or how density-dependence may be modi- fied by numerical effects (i.e., number-dependent mortali- ty). Both issues can have profound effects on spatial pat- terns of abundance and the regulation of local popula- tions. I address these issues through empirical studies in Moorea, French Polynesia, of the six bar wrasse ( Thalas- soma hardwicke), a reef fish that settles to isolated patch reefs. Per capita mortality rates of newly settled wrasse increased as a function of density and were well approxi- mated by the Beverton-Holt function for both naturally formed and experimentally generated juvenile cohorts. Average instantaneous mortality rates were a decelerating function of initial densities, indicating the per capita strength of density-dependence decreased with density. Results of a factorial manipulation of density and group size indicate that per capita mortality rates were simulta- neously density- and number-dependent; fish at higher densities and/or in groups had higher probabilities of dis- appearing from patch reefs compared with fish that were solitary and/or at lower densities. Mortality rates were ~30% higher for fish at densities of 0.5 fish/m 2 than at 0.25 fish/m 2 . Similarly, mortality rates increased by ~45% when group size was increased from 1 to 2 individ- uals per patch, even when density was kept constant. These observations suggest that the number of interact- ing individuals, independent of patch size (i.e., density- independent effects) can contribute to regulation of local populations. Overall, this work highlights a greater need to consider numerical effects in addition to density effects when exploring sources of population regulation.