cssi/SciSciGPT-SciSciNet huggingface dataset:
Compound specific amino acid δ 15 N in marine sediments: A new approach for studies of the marine nitrogen cycle

Abstract The nitrogen (N) isotopic composition (δ15N) of bulk sedimentary N (δ15Nbulk) is a common tool for studying past biogeochemical cycling in the paleoceanographic record. Empirical evidence suggests that natural fluctuations in the δ15N of surface nutrient N are reflected in the δ15N of exported planktonic biomass and in sedimentary δ15Nbulk. However, δ15Nbulk is an analysis of total combustible sedimentary N, and therefore also includes mixtures of N sources and/or selective removal or preservation of N-containing compounds. Compound-specific nitrogen isotope analyses of individual amino acids (δ15NAA) are novel measurements with the potential to decouple δ15N changes in nutrient N from trophic effects, two main processes that can influence δ15Nbulk records. As a proof of concept study to examine how δ15NAA can be applied in marine sedimentary systems, we compare the δ15NAA signatures of surface and sinking POM sources with shallow surface sediments from the Santa Barbara Basin, a sub-oxic depositional environmental that exhibits excellent preservation of sedimentary organic matter. Our results demonstrate that δ15NAA signatures of both planktonic biomass and sinking POM are well preserved in such surface sediments. However, we also observed an unexpected inverse correlation between δ15N value of phenylalanine (δ15NPhe; the best AA proxy for N isotopic value at the base of the food web) and calculated trophic position. We used a simple N isotope mass balance model to confirm that over long time scales, δ15NPhe values should in fact be directly dependent on shifts in ecosystem trophic position. While this result may appear incongruent with current applications of δ15NAA in food webs, it is consistent with expectations that paleoarchives will integrate N dynamics over much longer timescales. We therefore propose that for paleoceanographic applications, key δ15NAA parameters are ecosystem trophic position, which determines relative partitioning of 15N into source AA versus trophic AA pools, and the integrated δ15NAA of all common protein AA (δ15NTHAA), which serves as a proxy for the δ15N of nutrient N. Together, we suggest that these can provide a coupled picture of regime shifts in planktonic ecosystem structure, δ15N at the base of food webs, and possibly additional information about nutrient dynamics.
Vibrationally Enhanced Hydrogen Tunneling in the Escherichia coli Thymidylate Synthase Catalyzed Reaction

The enzyme thymidylate synthase (TS) catalyzes a complex reaction that involves forming and breaking at least six covalent bonds. The physical nature of the hydride transfer step in this complex reaction cascade has been studied by means of isotope effects and their temperature dependence. Competitive kinetic isotope effects (KIEs) on the second-order rate constant (V/K) were measured over a temperature range of 5−45 °C. The observed H/T (TV/KH) and D/T (TV/KD) KIEs were used to calculate the intrinsic KIEs throughout the temperature range. The Swain−Schaad relationships between the H/T and D/T V/K KIEs revealed that the hydride transfer step is the rate-determining step at the physiological temperature of Escherichia coli (20−30 °C) but is only partly rate-determining at elevated and reduced temperatures. H/D KIE on the first-order rate constant kcat (Dk = 3.72) has been previously reported [Spencer et al. (1997) Biochemistry 36, 4212−4222]. Additionally, the Swain−Schaad relationships between that Dk an...
Motion of an electron from a point source in parallel electric and magnetic fields.

Negative ions undergoing near-threshold photodetachment in a weak laser field provide an almost pointlike, isotropic source of low-energy electrons. External fields exert forces on the emitted coherent electron wave and direct its motion. Here, we examine the spatial distribution of photodetached electrons in uniform, parallel electric and magnetic fields. The interplay of the electric and magnetic forces leads to a surprising intricate shape of the refracted electron wave, and mutiple interfering trajectories generate complex fringe patterns in the matter wave. The exact quantum solution is best understood in terms of the classical electron motion.
Is domperidone a selective peripheral dopamine-receptor antagonist in vivo?

The ability of domperidone (DOM) to antagonize dopamine (DA) receptor agonist-induced hypothermia or hyperactivity was investigated in rats. Apomorphine (APO) or RDS-127 (2-di-n-propylamino-4,7-dimethoxyindane), two DA receptor agonists, produced dose-dependent hypothermia following subcutaneous (s.c.) administration. Also, RDS-127 produced hypothermia following lateral ventricular (i.c.v.) administration. The hypothermia produced by apomorphine or RDS-127 (given s.c. or i.c.v.) was antagonized by pretreatment with pimozide (0.25 mg/kg, i.p.) or domperidone (0.2, 1.0 and 5.0 mg/kg, i.p.) The hyperactivity produced by apomorphine was unaffected by pretreatment with domperidone. These data suggested that central DA receptors mediating temperature regulation, but not those mediating locomotor activity are accessible to peripherally administered domperidone. Therefore, domperidone may not be useful to differentiate hypothalamic (central) vs peripheral sites of action for DA receptor agonists in the rat.
Effect of PGE1 or PGE2 on PGF2α-induced luteolysis in nonbred ewes

Abstract Fifty-six ewes were used to study the effects of PGE1 or PGE2 plus PGF2α given into the perivascular space of the ovarian vascular pedicle on luteal function of nonbread ewes. All ewes receiving PGF2α had reduced levels of plasma progesterone and unoccupied receptors for LH at 24 hr after treatment regardless even if they received PGE1 or PGE2 concomitantly. Levels of plasma progesterone in ewes receiving only PGF2α were reduced further at 48 hour. Plasma progesterone and unoccupied receptors for LH of ewes receiving PGE2 + PGF2α were maintained at 48 hr at levels seen at 24 hr after treatment, while progesterone in ewes receiving PGE1 + PGF2α at 48 hr returned to levels seen in controls at 48 hr and unoccupied receptors for LH were three fold greater then controls.
Contact interactions in closed superstring field theory

We show that closed (type II and heterotic) superstring field theories, which are presently formulated without contact interactions in the light-cone gauge, do not have a stable vacuum state. States with arbitrary negative energy can be constructed in these theories; an explicit example is given. Negative energy states imply violation of the supersymmetry relation {Q−A, Q−B} = 2σABH. Using coherent state methods, we show that the super-Pioncare algebra is indeed violated by the standard light-cone gauge superstring hamiltonians, since the supercharge anticommulator generates local, 4-string contact interactions at O(λ2), where λ is the coupling of the 3-vertex. Contact interactions must therefore be added to the usual hamiltonian to restore supersymmetry and vacuum stability.
A RESEARCH NOTE FLAVOR‐MASKING AGENT EFFECTS ON SENSORY CHARACTERISTICS OF LACTATE‐CONTAINING CHICKEN MODEL SYSTEMS

To determine the effects of potential masking agents on sensory characteristics of ground chicken containing 3% or 4% sodium (SL) or potassium lactate(PL), sucrose, dextrose, lactitol, sorbitol or lysine were added individually to ground chicken breast tissue. Ground chicken in cylindrical containers was cooked to 72C in a circulating water bath, then evaluated at 45C, by a trained sensory panel for saltiness, bitterness, soapiness and sweetness. Chicken containing PL was more bitter and soapy, and less sweet than that containing SL. Chicken containing 4% SL was more salty and bitter than that containing 3% SL. Bitterness decreased in samples containing SL when 1% sucrose or lactitol was added. Sucrose also decreased soapiness in chicken containing PL. Sweetness did not increase in samples in which it decreased bitterness and soapiness. These results demonstrate that bitterness and soapiness imparted by lactates may be reduced by selected masking agents.
CELASTROL SUPPORTS SURVIVAL OF RETINAL GANGLION CELLS INJURED BY OPTIC NERVE CRUSH

The present study evaluates the effect of celastrol on the survival of retinal ganglion cells (RGCs) injured by optic nerve crush (ONC). Celastrol, a quinine methide triterpene extracted from the perennial vine Tripterygium wilfordii (Celastraceae), has been identified as a potential neuroprotective candidate in a comprehensive drug screen against various neurodegenerative diseases. Two weeks after ONC, the average density of remaining RGCs in retinas of animals treated with daily intraperitoneal (i.p.) injections of celastrol (1mg/kg) was approximately 1332 cells/mm(2), or 40.8% of the Celastrol/Control group. In retinas of the Vehicle/ONC group about 381 RGCs/mm(2) were counted, which is 9.6% of the total number of RGCs in the DMSO/Control group. This corresponds to approximately a 250% increase in RGC survival mediated by celastrol treatment compared to Vehicle/ONC group. Furthermore, the average RGC number in retinas of ONC animals treated with a single intravitreal injection of 1mg/kg or 5mg/kg of celastrol was increased by approximately 80% (760 RGCs/mm(2)) and 78% (753 RGCs/mm(2)), respectively, compared to Vehicle/ONC controls (422 cells/mm(2)). Injection of 0.2mg/kg of celastrol had no significant effect on cell survival, with the average number of RGCs being 514 cells/mm(2) in celastrol-treated animals versus 422 cells/mm(2) in controls. The expression levels of Hsp70, Hsf1, Hsf2, HO-1 and TNF-alpha in the retina were analyzed to evaluate the roles of these proteins in the celastrol-mediated protection of injured RGCs. No statistically significant change in HO-1, Hsf1 and Hsp70 levels was seen in animals with ONC. An approximately 2 fold increase in Hsf2 level was observed in celastrol-treated animals with or without injury. Hsf2 level was also increased 1.8 fold in DMSO-treated animals with ONC injury compared to DMSO-treated animals with no injury suggesting that Hsf2 induction has an injury-induced component. Expression of TNF-alpha in retinas of celastrol-treated uninjured and ONC animals was reduced by approximately 2 and 1.5 fold compared to vehicle treated animals, respectively. The observed results suggest that mechanisms underlying celastrol׳s RGC protective effect are associated with inhibition of TNF-alpha-mediated cell death.
Landslide susceptibility revealed by LIDAR imagery and historical records, Seattle, Washington

Abstract Light detection and ranging (LIDAR) data were used to visually map landslides, headscarps, and denuded slopes in Seattle, Washington. Four times more landslides were mapped than by previous efforts that used aerial photographs. The mapped landforms (landslides, headscarps, and denuded slopes) were created by many individual landslides. The spatial distribution of mapped landforms and 1308 historical landslides show that historical landslide activity has been concentrated on the mapped landforms, and that most of the landslide activity that created the landforms was prehistoric. Thus, the spatial densities of historical landslides on the landforms provide approximations of the landforms' relative susceptibilities to future landsliding. Historical landslide characteristics appear to be closely related to landform type so relative susceptibilities were determined for landslides with various characteristics. No strong relations were identified between stratigraphy and landslide occurrence; however, landslide characteristics and slope morphology appear to be related to stratigraphic conditions. Human activity is responsible for causing about 80% of historical Seattle landslides. The distribution of mapped landforms and human-caused landslides suggests the probable characteristics of future human-caused landslides on each of the landforms. The distribution of mapped landforms and historical landslides suggests that erosion of slope-toes by surface water has been a necessary condition for causing Seattle landslides. Human activity has largely arrested this erosion, which implies that landslide activity will decrease with time as hillsides naturally stabilize. However, evaluation of glacial-age analogs of areas of recent slope-toe erosion suggests that landslide activity in Seattle will continue for the foreseeable future.
Phytochemicals at the plant‐insect interface

Opportunities for genetic engineering of natural products are increasing, while discovery and development of synthetic insecticides and developmental regulators are declining. However, discovery and potential applications of natural compounds are constrained by present ecological knowledge and theory. Biochemistry offers additional perspective to chemical interaction across the interface between plant and herbivore. Phytochemical effects on an insect herbivore may be determined by physical, chemical, and biotic characteristics of the microenvironment during phytochemical transfer between plant and insect. The midgut lumen is often overlooked as part of this microenvironment. It initially determines rates of metabolism and uptake of phytochemicals into hemolymph, and ultimately the quantity of a compound seen by affected tissues. Additive processes such as absorption, binding, and transport by proteins in hemolymph may ultimately prove more crucial to toxication than subtractive processes such as metabolism and excretion. Uptake and transport of coumarins in hemolymph are being studied in larvae of the citrus root weevil Diaprepes abbreviatus. Studies with synthetic 7-amino-3-phenyl coumarin (coumarin-10) have preceded studies with natural coumarins. The fluorescence properties of coumarin-10 have enabled determination of absorption and binding to hemolymph proteins.
The effect of activation method on the properties of pecan shell-activated carbons

Pecan shell chars were activated using steam, carbon dioxide (CO2), or phosphoric acid (H3PO4) to produce granular activated carbons (GACs). The GACs were characterized for select physical, chemical and adsorption properties. Air oxidation of the GACs was used to increase copper ion (Cu2+) adsorption. BET surface areas of pecan carbons were equal to or greater than commercial GACs. Carbon dioxide activation favored microporosity, while the other activations increased both mesoporosity and microporosity. Bulk densities and particle attrition of the pecan shell GACs were generally similar to the commercial carbons. Air oxidation of steam-and CO2-activated GACs increased copper ion adsorption, although not to the same extent as GACs made by H3PO4 activation. Copper ion adsorption and the amount of titratable functional groups greatly exceeded the values for the commercial GACs. Steam-and CO2-activated pecan shell carbons were similar to but in some cases exceeded the ability of commercial GACs to remove certain organic compounds from water. GACs from pecan shells showed considerable commercial potential to remove metal ions and organic contaminants from water. © 1999 Society of Chemical Industry
Reliability and validity of a tool to assess oncology nurses' experiences with prognosis-related communication.

PURPOSE/OBJECTIVES: To establish the reliability and validity of a previously developed survey measuring nurses' experiences with prognosis-related communication. DESIGN: Psychometric testing of survey. SETTING: Mailed survey of Oncology Nursing Society (ONS) members. SAMPLE: 392 ONS members. METHODS: Reliability was analyzed using Cronbach's alpha. Total scale and subscale characteristics were evaluated through inter-item correlation matrices, average inter-item correlations, corrected item-to-total correlations, and Cronbach's alpha coefficients if the items were removed. Construct validity was assessed using exploratory factor analysis and contrasted group comparisons. MAIN RESEARCH VARIABLES: Measures of attitudes toward prognosis-related communication, demographic variables. FINDINGS: A three-factor structure emerged with acceptable reliability and validity. Contrasted group comparisons revealed differences in prognosis-related communication by nurses' years of experience with patients with cancer, level of education, and extent of education about prognosis-related communication. CONCLUSIONS: The final three-factor instrument, Prognosis-Related Communication in Oncology Nursing, was found to have acceptable reliability and validity. IMPLICATIONS FOR NURSING: The final instrument can serve as a tool to measure nurses' experiences with prognosis-related communication. Such measurements may guide interventions that aim to improve the process of prognostic disclosure and elucidate the role of the nurse in the process.
Effects of exercise on aging trends in cardiovascular dynamics

Strong cross sectional age trends were found in noninvasive cardiovascular testing of 50 men aged 36 to 57. They were first tested while resting immediately prior to undergoing a standard electrocardiographic exercise protocol (Bruce graded treadmill test). The reproducibility of each measurement was assessed and found to be high. Cardiovascular testing of each man was repeated during the recovery period 5 minutes after cessation of exercise. In most cases, measurements from resting and recovery periods were highly and significantly correlated. Despite this fact, cross sectional age trends based upon the recovery period were either not significant statistically, or greatly underestimated. These results demonstrate the capability of exogenous factors such as exercise, invasive testing, or psychic stress to vitiate strong cross sectional trends useful for research in aging.
PREPARATION OF LUMINESCENT SILICON NANOPARTICLES BY PHOTOTHERMAL AEROSOL SYNTHESIS FOLLOWED BY ACID ETCHING

CO2 laser-induced pyrolysis of silane (photothermal aerosol synthesis) was used to produce Si nanoparticles. Particles with an average diameter as small as 5 nm were prepared directly from silane in the gas phase. Etching these particles with mixtures of hydrofluoric acid (HF) and nitric acid (HNO3) is shown to be an effective method to reduce the size of the particles produced by silane pyrolysis. After etching, silicon particles with controlled visible luminescence at room temperature were produced. The wavelength of maximum photoluminescence (PL) intensity can be controlled from over 780–500 nm by controlling the etching time and conditions.
Twenty years of progress in biogerontology research.

The first 10 years of NIA's existence were characterized by funding for descriptive and discovery research, as the field had not yet come of age. As Couzin expressed it in the July 1, 2005 issue of Science, “Just 2 or 3 decades ago, research on aging was a backwater” (Couzin J 2005 How much can human life span be extended. Science 309: 83). With the isolation of long-lived animal mutants and the application of the tools of molecular biology and transgenic technology to biogerontology research, the situation has changed dramatically since then, and aging research has become increasingly mechanistic and respectable. This transition has been aided by some well-thought out research initiatives by the NIA, and the purpose of this article is to provide a brief summary of the progress made in the past 20 years, and describe the part that NIA initiatives and funding have played in this transition.
Tracheotomy in pediatric patients: a national perspective.

Background During the past 50 years, changes in the epidemiology of infectious diseases and the capabilities of medical technology have altered the indications for, and implications of, tracheotomy in children. Given the complexity of health care that these patients subsequently require, monitoring the performance of this procedure and patient outcomes across the diverse US health care system is warranted. Objectives To characterize children who received tracheotomies in 1997 and to determine whether disposition and mortality vary by region or health care system attributes. Design A nationally representative retrospective cohort drawn from an 80% sample of administrative hospital discharge records from all pediatric admissions in 22 states during 1997. Participants Patients aged 0 to 18 years who underwent tracheotomy. Methods The sampling scheme of the discharge records enabled the calculation of regional and national estimates and of age-stratified population-based rates of tracheotomies. Weighted descriptive statistical and Poisson analyses were performed. Results The 2065 tracheotomy procedures recorded in the Kids' Inpatient Database yielded a national estimate of 4861 tracheotomies performed in 1997. The mean length of hospital stay was 50 days, with a mean total facilities charge exceeding $200 000. The rate of tracheotomy was highest among infants and varied significantly across regions of the United States. Adjusting for other patient and health care system attributes, patients who received their tracheotomy in a children's hospital had half the risk of dying during the admission compared with patients who were cared for in a non–children's hospital. Hospitals that performed more pediatric tracheotomies had significantly lower mortality rates than hospitals with lesser case volume. Among patients who survived to discharge, those cared for in the Northeast were discharged to long-term care facilities at twice the rate of patients in the West. Children cared for in children's hospitals or in teaching hospitals were significantly less likely to be discharged to a long-term care facility. Conclusions Pediatric tracheotomy is associated with significant variation in rates and outcomes across the United States and across different hospital types. Further research to clarify the reasons for these associations is warranted.
Quantum Cascade Laser-Based Nitric Oxide Detection in Exhaled Breath of Patients with Chronic Obstructive Pulmonary Disease

A continuous wave quantum cascade laser operating at 5.45 µm coupled with integrated cavity output spectroscopy and wavelength modulation is detecting nitric oxide in exhaled breath of subjects with chronic obstructive pulmonary disease.
Development and age-associated differences in electron transport potential and consequences for oxidant generation.

Abstract We determined the activities of NADH dehydrogenase (ND), succinate dehydrogenase, and cytochromec oxidase (COX) in 29 skin fibroblast lines established from donors ranging in age from 12 gestational weeks to 94 years. The results of this study demonstrate that all three of the enzyme activities examined are greater in adult-derived fibroblasts than in the fetal cell lines. The ratio of enzyme activities that control electron entry into and exit from the electron transport chain varied directly with lucigenin-detected chemiluminescence (an indicator of⋅O2 − generation) and inversely with H2O2 generation. These results indicate a clear difference in the predominant oxidant species generated during fetal and adult stages of life. We also examined the mRNA abundances of different components of the electron transport chain complexes. We observed higher abundances of mitochondrial encoded mRNAs (COX 1 and ND 4) in cell lines established from adults than in fetal cells. No differences in the mRNA abundances of the nuclear encoded sequences (COX 4 and ND 51) were observed in fetal and postnatal-derived lines. Succinate dehydrogenase mRNA abundance was greater in cell lines established from postnatal donors than in fetal cell lines. No significant differences between cell lines established from young and old adults were detected in any of the parameters examined.
Tropospheric delay ray tracing applied in VLBI analysis

Tropospheric delay modeling error continues to be one of the largest sources of error in VLBI (very long baseline interferometry) analysis. For standard operational solutions, we use the VMF1 elevation-dependent mapping functions derived from European Centre for Medium-Range Weather Forecasts data. These mapping functions assume that tropospheric delay at a site is azimuthally symmetric. As this assumption is not true, we have instead determined the ray trace delay along the signal path through the troposphere for each VLBI quasar observation. We determined the troposphere refractivity fields from the pressure, temperature, specific humidity, and geopotential height fields of the NASA Goddard Space Flight Center Goddard Earth Observing System version 5 numerical weather model. When applied in VLBI analysis, baseline length repeatabilities were improved compared with using the VMF1 mapping function model for 72% of the baselines and site vertical repeatabilities were better for 11 of 13 sites during the 2 week CONT11 observing period in September 2011. When applied to a larger data set (2011–2013), we see a similar improvement in baseline length and also in site position repeatabilities for about two thirds of the stations in each of the site topocentric components.
The magic angle effect: a source of artifact, determinant of image contrast, and technique for imaging.

This review provides a formalism for understanding magic angle effects in clinical studies. It involves consideration of the fiber-to-field angle for linear structures such as tendons, ligaments, and peripheral nerves, disc-like and circular structures such as menisci and labra, as well as complex three-dimensional structures. There may be one or more fiber types with different orientations within each of these tissues. The orientation of these fibers to B0 is crucial in determining their magic angle effect. Tissues may show a variety of appearances depending on their baseline T2, as well as the increase in T2 produced by the magic angle effect. The appearances are affected by TE, which affects both the general tissue signal level and the change in signal produced by the magic angle effect, fiber-to-slice orientation, and partial volume effects. Deliberate positioning of structures and tissues at particular orientations to B0 can be used to increase the signal from tissues such as tendons and ligaments and so allow them to be imaged with conventional sequences. The technique can also be used to produce contrast between tissues with fibers that have different orientations to B0. J. Magn. Reson. Imaging 2007. © 2007 Wiley-Liss, Inc.
Pharmacokinetics and disposition of a novel NMDA glycine site antagonist (UK-240,455) in rats, dogs and man

1. UK-240,455 ((+) 6,7-dichloro-5-{ N- (2-hydroxyethyl)methanesulphonamido}-2,3 (1H,4H)-quinoxalinedione) is a potent, selective N- methyl D-aspartate (NMDA) glycine site antagonist that is being evaluated for the potential treatment of stroke. 2. UK-240,455 is predominately excreted unchanged in urine (58-68%) in rats, dogs and man following intravenous administration. The remainder of the dose is excreted unchanged in the faeces. It is considered that UK-240,455 is predominantly cleared by active renal tubular secretion and active hepatobiliary transport. In man, there is evidence that UK-240,455 undergoes glucuronidation. However, there is no evidence for this in rats and dogs. 3. UK-240,455 has a short elimination half-life in rats, dogs and man (0.4-1.4 h) and clearances of 12, 13 and 6 ml min − 1 kg − 1, respectively. The compound shows limited tissue distribution with volumes of distribution of 0.4-0.8 l kg − 1 in rats, dogs and man. The species' variation in pharmacokinetic parameters was related ...
A statistical study on characteristics of high latitude Pi 3 pulsations

The latitude and magnetic local time distributions of Pi 3 pulsations relative to polarization and the position of maximum intensity are presented using data from the high-latitude North American International Magnetospheric Study magnetometer network. These distributions are compared with those of Pc 5 and Pi 2 pulsations. The locus of Pi 3 maximum amplitude and the corresponding curve for Pc 5 are similar in general shape, but the former is located at considerably lower geomagnetic latitudes than the latter. For Pi 2 pulsations, the latitude of maximum amplitude is found to agree well with the auroral oval, whereas the locus of Pi 3 amplitude maximum deviates from the auroral oval appreciably in the dawn and dusk regions and is near the poleward border of the auroral oval in the premidnight region where the equatorward boundary of the oval is lowest in latitude. It is concluded that dayside Pi 3 pulsations may have a different generation mechanism from that for nightside Pi 3 events.
Parametric search visualization

This video provides a visualization of parametric search using as the underlying application an algorithm for computing a tangent to a level in arrangement proposed by Matousek [2]. The visualization is based on the framework of van~Oostrum and Veltkamp [6], which simplifies considerably the implementation of parametric search algorithms.
The potential adventive geographic range of glassy-winged sharpshooter, Homalodisca coagulata and the grape pathogen Xylella fastidiosa: implications for California and other grape growing regions of the world

Abstract The invasion risk posed by the xylem feeding hemipteran, Homalodisca coagulata (native to the southeast USA and northeast Mexico, and a recent invader of California (USA) and Tahiti) and a xylem-dwelling phytopathogenic bacterium, Xylella fastidiosa (native to the Americas and causative agent of Pierce's disease of grape vines), was examined using the computer climate modeling program CLIMEX. Model predictions indicated that suitable climatic conditions for H. coagulata and Pierce's disease causing strains of X. fastidiosa exist in almost all grape production areas of the world, and H. coagulata may be able to colonize areas unsuitable for X. fastidiosa. Additionally, the model indicated that regions north of California will be unable to sustain populations of both pests because of cold stress, and that irrigation of agricultural and urban areas in California's deserts has removed dry stress limitations, which when combined with a depauperate natural enemy fauna most likely facilitated successful invasion by H. coagulata. CLIMEX predicted that cold stress accumulation would exclude Pierce's disease causing strains of X. fastidiosa from France and northern and central grape producing areas of Spain and Italy. This result is incongruous with Pierce's disease reports from Kosovo in the Balkans and may suggest that cold-tolerant strains of X. fastidiosa that cause Pierce's disease exist which could exhibit invasion potential and establish in areas of Europe contrary to results reported here.
Work-Sampling as a Technique in Determining Labor Utilization of Dairy Plants

Summary Work-sampling was found to be a useful time-study technique in securing labor utilization data in a dairy plant. The work-sampling technique has several advantages over other time-study procedures in the collecting of data on labor requirements. The technique will obtain a maximum of information in a minimum of time, which is important both from the standpoint of the more efficient utilization of the time-study man's time and the cost to the plant. One man can study the entire plant operation, or any particular phase of the operation that management desires. Another feature of importance is that this technique will not interfere, to any extent, with the daily routine of plant operation. Workers pay little attention to the time-study observer, since the observations are made by mere glances at the workers, rather than by direct concentration on a specific employee, as utilized in a production study.
Statistical texture analysis based MRI quantification of Duchenne muscular dystrophy in a canine model

Golden retriever muscular dystrophy (GRMD) is a canine model of Duchenne muscular dystrophy (DMD) that has been increasingly used in both pathogenetic and therapeutic pre-clinical studies. Recent studies have shown that Magnetic resonance imaging (MRI) has great potential to noninvasively assess muscle disorders and has been increasingly used to monitor disease progression in DMD patients and GRMD dogs. In this study, we developed a statistical texture analysis based MRI quantification framework for GRMD. Our system was applied to a database of 45 MRI scans from 8 normal and 10 GRMD dogs in a natural history study. The dogs were longitudinally scanned at 3, 6 and 9 months of age. We first segmented six proximal limb muscles of each dog using a semi-automated, interpolation-based method and then automatically measured the 3D first-order histogram and novel 3D high-order run-length matrix based texture features within each segmented muscle. Our results indicated that MRI texture features has the ability to distinguish the normal and GRMD muscles at each age. Our experimental results demonstrated the potential of MRI texture measurements to serve as biomarkers to distinguish normal and muscular dystrophic muscles in DMD patients.
Desorption of polyacrylamide and hydrolized polyacrylamide from kaolinite surface

Abstract Desorption of labeled nonionic and hydrolyzed polyacrylamide from kaolinite in NaCl solutions is obtained using sodium metaphosphate as well as unlabeled polyacrylamide, whereas mere dilution with NaCl solution produced no measurable desorption. Extent of desorption achieved depends upon the charge characteristics of the polymer and the additives. Most interesting, desorption is found to depend upon the amount of original adsorption. Thus almost no polymer was desorbed at low surface coverages whereas up to 56% of a polyacrylamide polyacrylic acid could be desorbed at saturation surface coverage using sodium tripolyphosphate. Sodium metaphosphate desorbed less of the hydrolyzed polymer than the tripolyphosphate but both phosphates performed on an equal basis in the case of nonionic polyacrylamide. Results are discussed in terms of the configuration of the adsorbed polymer, detachment of individual segments of a polymer molecule from the mineral surface, and competition by the additives for the vacated sites and the contribution of the anionic species of the additives to the electrostatic repulsion between similarly charged polymers and mineral surface.
The complete cDNA coding sequence for the mouse proα1(I) chain of type I procollagen

The complete sequence of the cDNA for the pro alpha 1 (I) chain of mouse type I procollagen is presented. The encoded amino acid sequence shows 96% identity to the human pro alpha 1 (I) collagen chain.
Climatic Impact of Volcanic Eruptions

Volcanic eruptions have the potential to force global climate, provided they are explosive enough to emit at least 1–5 megaton of sulfur gases into the stratosphere. The sulfuric acid produced during oxidation of these gases will both absorb and reflect incoming solar radiation, thus warming the stratosphere and cooling the Earth’s surface. Maximum global cooling on the order of 0.2–0.3°C, using instrumental temperature records, occurs in the first 2 years after the eruption, with lesser cooling possibly up to the 4th year. Equatorial eruptions are able to affect global climate, whereas mid- to high-latitude events will impact the hemisphere of origin. However, regional responses may differ, including the possibility of winter warming following certain eruptions. Also, El Nino warming may override the cooling induced by volcanic activity. Evaluation of different style eruptions as well as of multiple eruptions closely spaced in time beyond the instrumental record is attained through the analysis of ice-core, tree-ring, and geologic records. Using these data in conjunction with climate proxy data indicates that multiple eruptions may force climate on decadal time scales, as appears to have occurred during the Little Ice Age (i.e., roughly AD 1400s–1800s). The Toba mega-eruption of ~75,000 years ago may have injected extremely large amounts of material into the stratosphere that remained aloft for up to about 7 years. This scenario could lead to the initiation of feedback mechanisms within the climate system, such as cooling of sea-surface temperatures. These interacting mechanisms following a mega-eruption may cool climate on centennial time scales.
The Effect of Procion Blue on Certain Metabolic Activities of Streptococcus mutans

Metabolic activities of S mutans were selectively affected by Procion Blue, known to cause covalent bonds and stable cross links in relation to carbohydrate and protein. In this study, despite the reduction in extra polysaccharide, the level of activity of glucosyltransferase was not significantly changed from the control level and colonial morphology was not transformed from smooth to rough. The results of the investigation imply at least interference with formation of extracellular polysaccharide, possibly in the bacterial cell wall.
The effect of evaporation losses in the analysis of counterflow cooling towers

Abstract In Merkel's method for the thermal design of counterflow cooling towers, the variation of the water flow from the tower inlet to outlet (due to evaporation losses) is neglected, which does not lead to a convervative design. In this analysis, the water evaporation losses are included in the energy balance and a new technique for the thermal design of cooling towers is developed. A comparison of the present analysis with the Merkel solution indicates that the error in the Merkel method may reach 12%, depending on the design conditions. The present solution is recommended where more accurate results are needed.
A nanoscale ordered materials diffractometer for the SNS

Abstract The Nanoscale Ordered Materials Diffractometer (NOMAD) is one of five neutron scattering instruments being managed within the Spallation Neutron Source (SNS) Instruments—Next Generation (SING) project. NOMAD is designed as a high-flux, medium-resolution diffractometer using a large bandwidth of neutron energies and extensive detector coverage to perform structural determinations of local order in crystalline and amorphous materials. The instrument will enable studies of a large variety of samples ranging from liquids, solutions, glasses, polymers, and nanocrystalline materials to long-range ordered crystals and will allow unprecedented access to high-resolution pair distribution functions, small-contrast isotope substitution experiments, small sample sizes, and parametric studies. Project completion for the instrument is anticipated in 2010 and a review of the design status will be given.
Migration of embryos in the anastomosed uterine horns of the pig.

One ovary was removed from 28 gilts and the uterus was transected, closed and anastomosed in one of four patterns. In three of the patterns the uterine horns were jointed near the uterotubal junction and in the fourth pattern the uterus formed one continuous tube from one oviduct to the cervix. Gilts were mated, then killed at 15 to 60 days of gestation when fetuses were located. The proportion of gilts pregnant was lower (P < 0.05) in the two groups requiring passage of sperm through an anastomosis than in the two groups where fertilization did not require that sperm traverse an anastomosis. Ten gilts were pregnant when killed and embryos were distributed in both horns in each gilt. Embryos can pass through an anastomosis and migrate and are spaced quite evenly even after disturbance of the normal anatomical relationships between uterine horns.
Abnormalities of mononuclear cell regulation in vitro in primary biliary cirrhosis1

ABSTRACT— In primary biliary cirrhosis (PBC) enhanced lymphocyte cytotoxicity, disruption by mononuclear cells of intrahepatic bile ducts, as well as high levels of circulating autoantibodies, immunoglobulins and immune complexes are found. These observations suggest the presence in PBC of defective regulation of immune functions. To evaluate immune regulation of T-cell and B-cell function in PBC, we measured the capability of suppressor cells generated by concanavalin A (Con A) from peripheral blood mononuclear cells (PBMC) to inhibit allogeneic T-cell proliferative responses as well as B-cell immunoglobulin synthesis in vitro. The inhibitory effect of Con A-induced suppressor cells on T-cell proliferation was significantly reduced in PBC patients compared to controls. This immunoregulatory defect did not correlate with indicators of disease activity and was not seen in patients with chronic extrahepatic biliary obstruction. In contrast, Con A-induced suppressor cells from PBC patients inhibited in vitro IgG and IgM synthesis normally. Finding that the potential to generate suppressor cell activity of B-cell immunoglobulin synthesis was preserved in PBC, we explored other mechanisms for elevated globulins in this disease. Comparing in vitro immunoglobulin synthesis by unstimulated and pokeweed mitogen-stimulated PBMC from PBC patients and controls, we found that baseline IgG synthesis in vitro was normal but baseline IgM synthesis significantly depressed in PBC. On the other hand, whereas PBMC from PBC patients responded normally to pokeweed mitogen stimulation of IgM synthesis, the same PBMC were refractory to pokeweed mitogen stimulation of IgG synthesis in vitro. These studies suggest that in PBC there is a dissociation between inducible suppressor cell activity of T-cell function, which is impaired, and inducible suppressor cell activity of B-cell immunoglobulin synthesis, which is preserved. Whereas a defect in regulation of cellular immune function may provide a permissive environment for initiation or perpetuation of cell-mediated autoimmune hepatobiliary injury in PBC, our studies failed to identify an extrinsic immunoregulatory defect to account for humoral immune aberrations, which may result, instead, from altered responsiveness intrinsic to B-cell progeny.
Chemical composition of a cellular fraction enriched in plasma membranes from sugarcane

Abstract The protein-lipid ratio in the enriched plasma membrane fraction of sugarcane leaves is almost 1:1. Virtually no phospholipid is present in the lipid fraction of the membranes. The major lipid is digalactosy diglyceride with smaller amounts of sterol glycosides, sterol esters, and acyl sterol glycosides. The potential importance of the glycolipids and two detected glycoproteins in the recognition phenomenon in plant diseases is discussed.
Hypertension enhances Aβ-induced neurovascular dysfunction, promotes β-secretase activity, and leads to amyloidogenic processing of APP

Hypertension (HTN) doubles the risk of Alzheimer’s disease (AD), but the mechanisms remain unclear. Amyloid-β (Aβ), a key pathogenic factor in AD, induces cerebrovascular dysfunction. We hypothesiz...
Complex Surgical Site Infections and the Devilish Details of Risk Adjustment: Important Implications for Public Reporting

Objective.To validate the National Nosocomial Infection Surveillance (NNIS) risk index as a tool to account for differences in case mix when reporting rates of complex surgical site infection (SSI).Design.Prospective cohort study.Setting.Twenty-four community hospitals in the southeastern United States.Methods.We identified surgical procedures performed between January 1, 2005, and June 30, 2007. The Goodman-Kruskal gamma or G statistic was used to determine the correlation between the NNIS risk index score and the rates of complex SSI (not including superficial incisional SSI). Procedure-specific analyses were performed for SSI after abdominal hysterectomy, cardiothoracic procedures, colon procedures, insertion of a hip prosthesis, insertion of a knee prosthesis, and vascular procedures.Results.A total of 2,257 SSIs were identified during the study period (overall rate, 1.19 SSIs per 100 procedures), of which 1,093 (48.4%) were complex (0.58 complex SSIs per 100 procedures). There were 45 complex SSIs identified following 7,032 abdominal hysterectomies (rate, 0.64 SSIs per 100 procedures); 63 following 5,318 cardiothoracic procedures (1.18 SSIs per 100 procedures); 139 following 5,144 colon procedures (2.70 SSIs per 100 procedures); 63 following 6,639 hip prosthesis insertions (0.94 SSIs per 100 procedures); 73 following 9,658 knee prosthesis insertions (0.76 SSIs per 100 procedures); and 55 following 6,575 vascular procedures (0.84 SSIs per 100 procedures). All 6 procedure-specific rates of complex SSI were significantly correlated with increasing NNIS risk index score (P< .05).Conclusions.Some experts recommend reporting rates of complex SSI to overcome the widely acknowledged detection bias associated with superficial incisional infection. Furthermore, it is necessary to compensate for case-mix differences in patient populations, to ensure that intrahospital comparisons are meaningful. Our results indicate that the NNIS risk index is a reasonable method for the risk stratification of complex SSIs for several commonly performed procedures.
Real-time three-dimensional Fourier-domain optical coherence tomography video image guided microsurgeries

The authors describe the development of an ultrafast three-dimensional (3D) optical coherence tomography (OCT) imaging system that provides real-time intraoperative video images of the surgical site to assist surgeons during microsurgical procedures. This system is based on a full-range complex conjugate free Fourier- domain OCT (FD-OCT). The system was built in a CPU-GPU heterogeneous computing architecture capable of video OCT image processing. The system displays at a maximum speed of 10 volume∕s for an image volume size of 160 × 80 × 1024 ðX × Y × ZÞ pixels. We have used this system to visualize and guide two prototypical microsur- gical maneuvers: microvascular anastomosis of the rat femoral artery and ultramicrovascular isolation of the retinal arterioles of the bovine retina. Our preliminary experiments using 3D-OCT-guided microvascular anastomosis showed optimal visualization of the rat femoral artery (diameter < 0.8 mm), instruments, and suture material. Real-time intraoperative guidance helped facilitate precise suture placement due to optimized views of the vessel wall during anastomosis. Using the bovine retina as a model system, we have performed "ultra microvascular" feasibility studies by guiding handheld surgical micro-instruments to isolate retinal arterioles (diameter ∼0.1 mm). Isolation of the microvessels was confirmed by successfully passing a suture beneath the vessel in
Peer-Led Team Learning: 2008 James Flack Norris Award Address

This paper offers an overview of the development of the peer-led team learning (PLTL) model for teaching and learning chemistry, from the personal journeys of the authors in their classrooms to the national dissemination of the model to the full range of colleges and universities and to other STEM disciplines. In the PLTL model, students who have done well in the course serve as peer-leaders to facilitate Workshops that supplement the lecture part of the course for new students. In the weekly Workshops, 6−8 students engage in active debate, discussion, and problem solving under the guidance of the peer leaders. A diverse faculty team led the development of instructional materials for the Workshops, methods to train peer leaders, and tactics to institutionalize PLTL. Students and leaders value the peer-led Workshops, and results from within the PLTL project (as well as numerous independent studies) demonstrate significant gains in student learning for both groups. PLTL remains an active area of research an...
Crystallization and preliminary X-ray diffraction studies of an anti-4-hydroxy-3-nitrophenylacetic acid monoclonal antibody Fab fragment complexed with immunizing and heteroclitic haptens.

The Fab fragment of the anti-4-hydroxy-3-nitrophenylacetic acid monoclonal antibody, 88C6/12, has been crystallized in the presence of the eliciting hapten, 4-hydroxy-3-nitrophenacetyl-e-aminocaproic acid (NP-aminocap) and the heteroclitic iodinated analog, 4-hydroxy-3-iodo-5-nitrophenylacetyl-e-aminocaproic acid (NIP-aminocap). Crystals obtained by precipitation with 32% (wv) polyethylene glycol 3400 in the presence of 40 to 400 μm of either NP-aminocap or NIP-aminocap, belong to the orthorhombic space group P212121 with cell dimensions a = 81.2 A, b = 86.9 A, c = 131.1 A. The cell volume suggests the presence of two molecules of the complex per asymmetric unit. Analysis of the Patterson function indicates that these two molecules are related by a local 2-fold axis parallel to the crystallographic b axis located at x = 0.218 and z = 0.25.