cssi/SciSciGPT-SciSciNet huggingface dataset:
Sulfolobus Acidocaldarius Synthesizes UMP via a Standard De Novo Pathway: Results of Biochemical-Genetic Study

A genetic approach was used to establish the route of UMP biosynthesis in Sulfolobus acidocaldarius, a member of the hyperthermophilic division (the Crenarchaeota) of the Archaea domain. Pyrimidine auxotrophs of S. acidocaldarius DG6 were isolated by direct selection and by brute-force methods. Enzymatic assay of extracts from wild-type S. acidocaldarius, from pyrimidine auxotrophs, and from phenotypic revertants demonstrated that S. acidocaldarius synthesizes UMP via orotate in six enzymatic steps corresponding to the de novo pathway of other organisms. The results also show that a single carbamoyl phosphate synthetase supplies both the pyrimidine and arginine pathways of this organism. To gain similar insight into pyrimidine salvage pathway(s), prototrophic mutants resistant to toxic pyrimidine analogs were also isolated and characterized. The results suggest that a single class of mutants which had acquired elevated resistance to four different 5-fluoropyrimidines had been isolated. These fluoropyrimidine-resistant mutants appear to have a regulatory defect leading to overproduction of one or more endogenous pyrimidine compounds. Images
Effects of evaporation and solute concentration on presence and composition of water in and around the waste package at Yucca Mountain

For the proposed repository at Yucca Mountain, the amount, timing, and expected composition of water contacting the waste package are major concerns. In the presence of thermal loading from radioactive decay, a flow system is set up with water leaving as vapor and returning as liquid flowing through the matrix and fractures. A hypothesis is developed suggesting that most water in the vicinity of the waste package evaporates, leaving behind a scale deposit and concentrated solution. The vapor pressure lowering caused by the brine solution maintains a water film on the rock and waste package materials even in the presence of a dry environment with thermal gradients. The chemical environment within which container corrosion and spent fuel alteration occur is anticipated to be an initial period of concentrated brine, followed by solutions of lower ionic strength as the repository cools. The specific environment and timing could vary widely between different waste packages and within individual waste packages subsequent to container failure.
THE COMPROMISE DECISION SUPPORT PROBLEM: MODELING THE DEVIATION FUNCTION AS IN PHYSICAL PROGRAMMING

Abstract The Archimedean and preemptive formulations that are currently used in the goal formulation of the Compromise Decision Support Problem (DSP) suffer two major drawbacks related to the arbitrary definition of priority levels and targets for multiple objectives. The Archimedean formulation is very difficult to implement because there is no consistent way to determine a prioria correct set of weights. Thus, choosing weights is either done arbitrarily or by cumbersome iterations. In the preemptive approach one objective is assumed to be infinitely more important than the others. Also, in the Compromise DSP it is necessary to define targets for each goal, and usually those targets are selected based on “educated guesses” or through an inefficient process of iteration. These shortcomings undermine the effectiveness of the Compromise DSP as a design tool. These problems can be amended by modifying the Compromise DSP according to the Linear Physical Programming (LPP) formulation. In this paper the modific...
The Thermodynamics of Folding of a β Hairpin Peptide Probed Through Replica Exchange Molecular Dynamics Simulations

Peptides that possess a well defined native state are ideal model systems to study the folding of proteins. They possess many of the complexities of larger proteins, yet their small size renders their study computationally tractable. Recent advances in sampling techniques, including replica exchange molecular dynamics, now permit a full characterization of the thermodynamics of folding of small peptides. These simulations not only yield insight into the folding of larger proteins, but equally importantly, they allow, through comparison with experiment, an objective test of the accuracy of force fields, water models and of different numerical schemes for dealing with electrostatic interactions. In this account, we present a molecular dynamics simulation of a small β-hairpin peptide using the replica exchange algorithm and illustrate how this enhanced sampling scheme enables a thorough characterization of the native and unfolded states, and sheds new light into its folding mechanism.
Biosynthesis and characterization of type X collagen in human fetal epiphyseal growth plate cartilage

Summary We examined in vitro collagen biosynthesis by organ cultures from human fetal epiphyseal growth plate cartilage. The biosynthetic products were characterized by NaCl fractional precipitation, limited proteolytic digestion, and sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis. Organ cultures of human fetal epiphyseal growth plate cartilage synthesized large amounts of type X collagen in addition to type II, type IX, and type XI collagens. The individual polypeptide chains of human type X collagen migrated with an apparent M r of 45 kDa after proteolytic digestion with pepsin. The migration pattern of these molecules did not change when examined under reducing and nonreducing conditions, indicating that they did not contain intrahelical disulfide bonds. Comparison of the rates at type X collagen biosynthesis at weeks 20 and 24 of human fetal development showed a marked increase of 24 weeks. Northern hybridization analysis of total RNA from freshly isolated epiphyseal growth plate chondrocytes with a cDNA corresponding to the carboxyl terminus of human type X collagen indicated that the developmental increase of type X collagen production is determined by pre-translational mechanisms.
Influence of pH and ionic strength on the metal profile of impregnation catalysts

Abstract In this study the influence of pH and ionic strength on the final metal distribution is investigated. After impregnation, catalysts are usually dried at temperatures between 50°C and 200°C. During this process, a redistribution of the metal occurs, which is a complex function of the drying conditions, the properties of the impregnating solution and the support material. In our model, transport in the gas and liquid phase is described by the dusty gas model, and the Nernst–Plank equation, respectively. The metal adsorption on the porous support is described by the Revised Physical Adsorption model developed by Agashe and Regalbuto (J. Colloid Interface Sci. 185 (1997) 174). In their model, the adsorption constant is a function of the pH and the ionic strength of the liquid solution. The results show that for a positively charged metal complex, the impact of drying is strong when the initial pH of the liquid solution is below the point of zero charge (PZC). In such a case, the metal accumulates at the particle surface when the convective flow is strong (high temperature), and at the particle center when the solute-metal diffusivity is high. A comparison of our model with a drying model that assumes a constant adsorption equilibrium constant shows that the variations of pH and ionic strength cannot be ignored when the initial adsorption constant is low and the pH below the PZC. In such cases, the adsorption constant increases over several orders of magnitude when pH and ionic strength effects are accounted for.
Reproductive Capacity of Dairy Bulls. II. Gonadal and Extra-Gonadal Sperm Reserves as Determined by Direct Counts and Depletion Trials; Dimensions and Weight of Genitalia

Summary Extra-gonadal sperm reserves (EGR) determined by direct counts averaged 69.4 billion for 15 sexually rested (SR) bulls, 73.5 billion for 15 sexually rested bulls depleted just before slaughter (SR-D), and 68.0 billion for five bulls ejaculated six or seven times per week for at least 6 wk. prior to slaughter (6–7 x). While total EGR, which included an average of 38.5 billion sperm collected on the day of slaughter from SR-D bulls and 10.5 billion from 6–7 × bulls, did not vary significantly among the three groups, sperm distribution was significantly different. Sperm counts of the caput, corpus, and cauda epididymis averaged 19.4, 4.7, and 37.6 billion for SR bulls, 16.2, 3.0, and 13.7 billion for SR-D bulls, and 22.6, 5.2, and 26.4 billion for 6–7 × bulls. Depletion removed 52.8 ± 2.3% of the total EGR of SR-D bulls; although the cauda epididymis was nearly emptied, partial replenishment with sperm from the caput and corpus occurred during the 60- to 90-min. interval between the end of depletion and slaughter. Daily sperm output for the 6–7 × bulls averaged 4.9 billion for 6 wk. The sperm content of the cauda epididymis was 25% lower than if they had been sexually rested. The ductus deferens and ampulla of SR bulls contained only 7.6 billion sperm. When corrected for preslaughter treatment, the EGR for the 35, 76 ± 5-mo.-old bulls averaged 72.6 billion sperm. Preslaughter treatment did not affect gonadal sperm reserves. Fifty testes, averaging 374 g., contained 20.2 billion sperm, or 54.8 ± 1.0 million per gram. Testis sperm numbers were highly significantly correlated (+ 0.62) with testis weight. The highly significant correlation (+ 0.87) between EGR and total sperm removed in a depletion should permit estimation of EGR in living animals by depletion trials of about 20 ejaculates. Gonadal sperm reserves were not significantly correlated to epididymal sperm reserves in SR bulls. The independence of testicular sperm production and storage of sperm in the excurrent duct system is stressed. Genitalia dimensions and weight for 55 bulls are presented by breeds and ages.
Tolerance of normal rabbit femoral arteries to single high dose external beam irradiation.

Abstract Purpose. We gave high single doses of external radiation to normal vessels to produce vascular injury and establish the dose tolerance in an animal model. We also performed immunohistochemical staining for macrophages and smooth muscle cells to assess qualitative changes in their populations. Methods. Following direct bilateral inguinal cutdown in New Zealand white rabbits, single doses of 15, 20 and 30 Gy were delivered to one vessel. At predetermined time intervals following treatment, the animals underwent angiography and were sacrificed. Both systems were harvested and analyzed, and their luminal and medial areas compared. Results. No statistically significant differences were found between any treatment vessel and its contralateral control at any time point. In addition, no alterations in subintimal or medial content of macrophages or smooth muscle cells were observed. Conclusions. Our data suggest that single radiation doses as high as 30 Gy appear to be well tolerated in the normal, uninjured rabbit vessel over a 6-month follow-up. However, the use of a diseased vessel model and longer follow-up times need to be studied to provide a better clinical understanding of the basic radiobiology of this technique.
Intrinsic Changes and Extrinsic Influences of Myogenic Stem Cell Function During Aging

The myogenic stem cell (satellite cell) is almost solely responsible for the remarkable regeneration of adult skeletal muscle fibers after injury. The availability and the functionality of satellite cells are the determinants of efficient muscle regeneration. During aging, the efficiency of muscle regeneration declines, suggesting that the functionality of satellite cells and their progeny may be altered. Satellite cells do not sit in isolation but rather are surrounded by, and influenced by, many extrinsic factors within the muscle tissue that can alter their functionality. These factors likely change during aging and impart both reversible and irreversible changes to the satellite cells and on their proliferating progeny. In this review, we discuss the possible mechanisms of impaired muscle regeneration with respect to the biology of satellite cells. Future studies that enhance our understanding of the interactions between stem cells and the environment in which they reside will offer promise for therapeutic applications in age-related diseases.
Unsteady internal boundary layer analysis applied to gun barrel wall heat transfer

Abstract Convective heating to gun barrel walls is of considerable importance when attempting to evaluate the degradation of performance in a ballistic device. The purpose of this study was to isolate and examine convective heating in order to calculate gun tube wall temperature as occurs during the firing of a projectile. Internal flow structure was decoupled by specifying in viscid core properties through measured and assumed axial and temporal variations. A fluid mechanics model was then used to solve the unsteady, compressible, and turbulent momentum and energy boundary layer development at discrete piston locations. Shear layer solutions were coupled through the energy equation. A consideration of radial heat conduction into the bore surface of the ballistic device was used to predict the interior wall temperature history at all locations behind a moving projectile. The results, when compared to those predictions which utilize integral methods and assumed known heat transfer coefficients, indicate that conventional integral methods do not adequately represent the convective heat transfer process. The influence of transverse curvature on the surface heating of small bore guns was examined. Recommendations are given for improving the present model.
Optimal diet selection with variable nutrient intake: Balancing reproduction with risk of starvation

Abstract We develop a model to predict optimal diet selection when energy intake varies over consecutive foraging periods. The model assumes that fitness is maximized when the forager maximizes its net reproduction (survivorship × reproduction) over some specified time period. This goal differs from earlier risk-sensitive foraging models which assume that the forager minimizes the risk of failing to satisfy minimum requirements for survivorship or reproduction. In our model, the net number of offspring produced per reproductive bout is expressed as an explicit function of fitness gained from reproduction and fitness lost due to starvation risk for different potential diets. Potential model solutions are explored graphically and are compared with solutions for previous foraging models. In general, the model predicts that foragers with a goal of maximizing net reproduction should accept greater risks of starvation than foragers with a goal of minimizing the risk of failing to satisfy minimum energy requirements.
A simple and efficient methodology to approximate a general non-Gaussian stationary stochastic process by a translation process

Some widely used methodologies for simulation of non-Gaussian processes rely on translation process theory which imposes certain compatibility conditions between the non-Gaussian power spectral density function (PSDF) and the non-Gaussian probability density function (PDF) of the process. In many practical applications, the non-Gaussian PSDF and PDF are assigned arbitrarily; therefore, in general they can be incompatible. Several techniques to approximate such incompatible non-Gaussian PSDF/PDF pairs with a compatible pair have been proposed that involve either some iterative scheme on simulated sample functions or some general optimization approach. Although some of these techniques produce satisfactory results, they can be time consuming because of their nature. In this paper, a new iterative methodology is developed that estimates a non-Gaussian PSDF that: (a) is compatible with the prescribed non-Gaussian PDF, and (b) closely approximates the prescribed incompatible non-Gaussian PSDF. The corresponding underlying Gaussian PSDF is also determined. The basic idea is to iteratively upgrade the underlying Gaussian PSDF using the directly computed (through translation process theory) non-Gaussian PSDF at each iteration, rather than through expensive ensemble averaging of PSDFs computed from generated non-Gaussian sample functions. The proposed iterative scheme possesses two major advantages: it is conceptually very simple and it converges extremely fast with minimal computational effort. Once the underlying Gaussian PSDF is determined, generation of non-Gaussian sample functions is straightforward without any need for iterations. Numerical examples are provided demonstrating the capabilities of the methodology.
Asymmetric Colloidal Dimers under Quasi-Two-Dimensional Confinement

The synthesis and assembly of mildly fused asymmetric polystyrene/silica dimers confined to gap heights intermediate to an in-plane monolayer and an out-of-plane monolayer are explored. Using real-space confocal microscopy, we show that structures evolve from an oblique two-dimensional (2D) phase to a quasi-2D rotator, and finally to an upright hexagonally close-packed monolayer. The existence of the novel quasi-2D state, where out-of-plane motion is allowed, highlights the critical role that confinement dimensionality plays on the nature of ordering in complex colloidal systems.
Every solution has a problem.

(2001). Every solution has a problem. Disability and Rehabilitation: Vol. 23, No. 1, pp. 30-35.
Lethal and sublethal effects of embryonic and larval exposure of Hyla versicolor to stormwater pond sediments.

Stormwater ponds are common features of modern stormwater management practices. Stormwater ponds often retain standing water for extended periods of time, develop vegetative characteristics similar to natural wetlands, and attract wildlife. However, because stormwater ponds are designed to capture pollutants, wildlife that utilize ponds might be exposed to pollutants and suffer toxicological effects. To investigate the toxicity of stormwater pond sediments to Hyla versicolor, an anuran commonly found using retention ponds for breeding, we exposed embryos and larvae to sediments in laboratory microcosms. Exposure to pond sediments reduced survival of embryos by approximately 50% but did not affect larval survival. Larvae exposed to stormwater pond sediment developed significantly faster (x = 39 days compared to 42 days; p = 0.005) and were significantly larger at metamorphosis (x = 0.49 g compared to 0.36 g; p < 0.001) than controls that were exposed to clean sand. Substantial amounts (712-2215 mg/l) of chloride leached from pond sediments into the water column of treatment microcosms; subsequently, survival of embryos was negatively correlated (r (2) = 0.50; p < 0.001) with water conductivity during development. Our results, along with the limited number of other toxicological studies of stormwater ponds, suggest that road salt contributes to the degradation of stormwater pond habitat quality for amphibian reproduction and that future research should focus on understanding interactions among road salts and other pollutants and stressors characteristic of urban environments.
A temporal channel for information in sparse sensory coding.

Summary Background Sparse codes are found in nearly every sensory system, but the role of spike timing in sparse sensory coding is unclear. Here, we use the olfactory system of awake locusts to test whether the timing of spikes in Kenyon cells, a population of neurons that responds sparsely to odors, carries sensory information to and influences the responses of follower neurons. Results We characterized two major classes of direct followers of Kenyon cells. With paired intracellular and field potential recordings made during odor presentations, we found that these followers contain information about odor identity in the temporal patterns of their spikes rather than in the spike rate, the spike phase, or the identities of the responsive neurons. Subtly manipulating the relative timing of Kenyon cell spikes with temporally and spatially structured microstimulation reliably altered the response patterns of the followers. Conclusions Our results show that even remarkably sparse spiking responses can provide information through stimulus-specific variations in timing on the order of tens to hundreds of milliseconds and that these variations can determine the responses of downstream neurons. These results establish the importance of spike timing in a sparse sensory code.
The environmental audit. II. Application to stream network design

The planning and execution of water quality management programs requires careful collection and analysis of data coupled with a systematic review and analysis of programmatic success. The environmental audit is a tool which facilitates improved water quality planning and management. This article demonstrates the utility of the environmental audit by reviewing portions of a comprehensive review of the water quality management program for the state of Idaho. The audit is a tool which forces careful design of a sampling program before data are collected. In the audit approach, program objectives are clearly stated prior to initiation of sampling. Stated objectives are also evaluated regularly to identify tension points, that is, conflicts between expectations and reality. In the example taken from Idaho, a management review team followed a directive to redesign the water quality monitoring program. We present a summary of the redesign as proposed by that team, to illustrate the results of a typical review of monitoring programs. That summary is followed by an example of how the proposed program would differ if the audit approach had been used. The two approaches offered both coincident and conflicting recommendations. Management review team and audit recommendations for lake sampling programs were similar even though a different process was used to develop the recommendations. The most striking contrast between the two results lies in the review team's approach to the problem. The directives followed, and the team's responses, concentrate on tools, such as increasing biological monitoring or reliance on monthly BWMP stations. In contrast, the audit results stress addressing management questions for which clear objectives have been stated, depending on specific tools only as needed to meet stated objectives. Although the audit does integrate externalities in its structure, it is little affected by economic or political influences. A major strength of the audit approach is its ability to provide defensible data for management decision making.
High-Stakes Testing: Barrier to Gifted Girls in Mathematics and Science?

The gender gap in scores on the mathematics section of the Scholastic Assessment Test (SAT-M) is currently approximately 30 points for academically gifted middle school students who take the SAT as part of Talent Search participation. This paper explores possible reasons for the gap, including test bias, variability in scores, the timed nature of the test, and environmental factors. When the SAT-M is used as the sole criterion for admission, gender differences in scores mean that disparate numbers of boys and girls are identified for high-level mathematics and science programs. Solutions to the problem are proposed, taking the perspective that the goal of the special programs is to identify and serve students who are likely to benefit from and be successful in such programs.
Mucosal Vaccination with Recombinantly Attenuated Staphylococcal Enterotoxin B and Protection in a Murine Model

Previous work in our laboratory revealed that mice parenterally vaccinated with recombinantly attenuated staphylococcal enterotoxin (SE) or toxic shock syndrome toxin 1 develop protective antibodies against a lethal intraperitoneal (i.p.) toxin challenge. This study investigated the efficacy of nasal and oral immunizations with an SEB vaccine (SEBv) toward an i.p. or mucosal (via an aerosol) toxin challenge. Both vaccination routes, with the immunoadjuvant cholera toxin (CT), elicited comparable SEB-specific immunoglobulin A (IgA) and IgG levels in saliva. Nasal or oral inoculations also generated SEB-specific IgA, IgG, and IgM in the serum, but the nasal route yielded higher specific IgG titers. SEBv alone, when given nasally or orally, did not induce any detectable SEB-specific antibody. Mice vaccinated mucosally were protected against a 50% lethal dose of wild-type SEB given i.p. or mucosally, thus demonstrating that nasal or oral administration of this SEBv, with CT, elicits systemic and mucosal antibodies to SEB that protect against SEB-induced lethal shock.
Habitat segregation among mimetic ithomiine butterflies (Nymphalidae)

The extensive wing pattern diversity observed among sympatric unpalatable mimetic butterflies is difficult to explain. Diversity is a paradox because selection by predators is expected to drive local species to use the same aposematic patterns. Habitat segregation among mimicry complexes has been suggested as a hypothesis to explain how diversity could be maintained. However, very few studies have tested this hypothesis. To test whether mimicry complexes are associated with particular habitats, I sampled a diverse assemblage of ithomiine butterflies from eastern Ecuador comprising nine discrete mimicry complexes. Butterflies were sampled in four habitats varying along a gradient of succession. A total of 43 species and 902 individuals were sampled. Ithomiine species richness and abundance were lowest in open habitats, and habitat preferences were documented for many species. Mimicry complexes exhibited significant habitat differences supporting the role of habitat segregation in maintaining mimetic diversity. However, there was obvious overlap among mimicry complexes, particularly involving the two numerically dominant patterns at the site. The pattern of segregation appears to be driven by common species, with relatively little evidence that the distribution of rarer species matches that of the more abundant species. Thus, habitat segregation is likely to play a role in the evolution of mimetic diversity as a result of segregated abundant model species, but the effect is probably weak and other factors are also important.
Optical Tomography on Simple Riemannian Surfaces

ABSTRACT Optical tomography means the use of near-infrared light to determine the optical absorption and scattering properties of a medium. In the stationary Euclidean case the dynamics are modeled by the radiative transport equation, which assumes that, in the absence of interaction, particles follow straight lines. Here we shall study the problem in the presence of a Riemannian metric where particles follow the geodesic flow of the metric. In particular, we study the problem in dimension two, where the analysis is more delicate than in the higher dimensional cases.
Changes in Oxygenation With Inhaled Nitric Oxide in Severe Bronchopulmonary Dysplasia

BACKGROUND Severe bronchopulmonary dysplasia (BPD), which is associated with high mortality and morbidity, is thought to be the result of mechanical, inflammatory, and oxidant injury to the immature lung, and includes the development of pulmonary hypertension with vascular remodeling. METHODS A phase II pilot study was conducted to determine the effect of inhaled nitric oxide (iNO) on oxygenation in severe BPD. This was an open-labeled, noncontrolled trial to evaluate safety and determine appropriate dosing for a future randomized controlled trial. Infants were eligible for enrollment if they were >/=4 weeks of age and ventilator dependent with a mean airway pressure of >/=10 cm H2O and an FIO2 of >/=0.45. Study infants received iNO (20 ppm) for 72 hours, and FIO2 was adjusted to maintain oxygen saturations of >92%. Infants who had a >/=15% reduction in FIO2 after 72 hours received prolonged treatment with low-dose iNO, weaning by 20% every 3 days as tolerated. FINDINGS Sixteen preterm infants (23-29 weeks of gestation), age 1 to 7 months, were enrolled. Eleven of 16 infants had a significant increase in PaO2 after 1 hour of iNO (median change, 24 mm Hg; range, -15 to 59 mm Hg; P /=15% reduction in FIO2, and 7 of the 11 had >/=35% reduction (P <. 01). Among the 11 infants who responded to iNO after 72 hours, 10 had a sustained improvement in oxygenation throughout their course of treatment (duration, 8-90 days), and ventilator support could also be decreased. No adverse effects from iNO (increased methemoglobin, bleeding, or increased plasma 3-nitrotyrosine) were observed. Four of the 11 infants (36%) who responded to iNO ultimately weaned off mechanical ventilation and 4 died, whereas all the infants who failed to respond to iNO either died or continue to require mechanical ventilation. INTERPRETATION We conclude that the use of low-dose iNO may improve oxygenation in some infants with severe BPD, allowing decreased FIO2 and ventilator support without evidence of adverse effects. Randomized clinical trials of low-dose iNO for BPD are warranted.
Improving the effect of guarantees: : the role of a retailer's reputation

Abstract This research examines the interaction of two cues, retailer reputation and guarantees on evaluations. Extending Mandler's (1982) incongruity framework, we illustrate across three studies how moderately incongruent signals can be combined to enhance evaluations. Unique to our application of moderate incongruity, however, is the fact that guarantee cues can be incongruent with the retailer's reputation, in terms of domain (e.g., price matching guarantee (PMG) offered by provider whose reputation is based on service, not pricing) or valence (e.g., PMG offered by retailer known for carrying expensive merchandize). This dual perspective on the source of incongruity (domain or valence) is important and highlights when guarantees enhance evaluations.
Vasodilation to PTH (1-84) in bone arteries is dependent upon the vascular endothelium and is mediated partially via VEGF signaling.

Abstract Background Intermittent PTH administration directly stimulates osteoblasts; however, mechanisms of bone accrual that are independent of the direct actions on osteoblasts may be under-appreciated. Our aims were to decipher (1) whether PTH 1-84 augments vasodilation of the femoral principal nutrient artery (PNA), (2) whether 15 days of intermittent PTH 1-84 augments endothelium-dependent and/or -independent vasodilation of the femoral PNA, and (3) the signaling mechanisms involved. Methods Experiment 1: Femoral PNAs from male Wistar rats were exposed to cumulative doses of PTH 1-84 with and without an anti-vascular endothelial growth factor antibody and/or the endothelial NO synthase inhibitor l -NAME. Experiment 2: Male Wistar rats were administered PTH and/or the anti-VEGF antibody for 2 weeks. Subsequently, endothelium-dependent vasodilation to acetylcholine and endothelium-independent vasodilation to sodium nitroprusside were assessed. In addition, endothelium-dependent signaling pathways were analyzed by use of l -NAME and/or and the cyclooxygenase inhibitor indomethacin. Results Cumulative doses of PTH 1-84 induced vasodilation of the femoral PNA, which was reduced by 38% and 87% with the anti-VEGF antibody and l -NAME, respectively. Secondly, 2 weeks of intermittent PTH 1-84 administration doubled trabecular bone volume, augmented bone formation parameters and reduced osteoclast activity. In addition, PTH enhanced endothelium-dependent vasodilation via up-regulation of NO. Co-administration of the anti-VEGF antibody (1) inhibited the PTH-induced increase in bone volume and remodeling parameters and (2) blunted the augmented vasodilator responsiveness of the PNA. Finally, endothelium-dependent vasodilation in PTH-treated rats was highly correlated with trabecular bone volume. Conclusion As hypothesized, PTH enhanced endothelium-dependent vasodilation of the femoral PNA via augmented NO production and was mediated partially through VEGF signaling. Further, vasodilation to PTH appears independent of vascular smooth muscle cell participation. More importantly, the strong association between vasodilation and bone volume suggests that bone arteriolar function is critical for PTH-induced bone anabolism.
Effect of deuterium oxide on the saprophytic culture of Claviceps. I. Nutritional factors.

At high concentrations of heavy water, the saprophytic growth of a clavine-producing strain of Claviceps (strain 47A-Tyler) is highly dependent upon the carbon source. Minimal media containing only succinate as the carbon source support growth at D 2 O levels up to 90 per cent, but growth is progressively inhibited by deuterium oxide, and is extremely slow at the 80–90 per cent level. The addition of glucose, however, leads to good vegetative growth not only at 90 per cent D 2 O, but also at 99.6 per cent D 2 O. Preliminary investigations indicate that alkaloid accumulation is also a function of both deuterium concentration and the composition of the medium.
Clinical and Etiological Update of Myofascial Pain from Trigger Points

Objectives: To review clinical literature concerning the prevalence, diagnostic criteria, and treatment of myofascial trigger points [TrPs] and to summarize a new understanding of their etiology. Findings: In three studies, the prevalence of myofascial TrPs among patients complaining of pain anywhere in the body ranged from 30% to 93%; among patients with chronic craniofacial pain, 55%; and for lumbogluteal pain, 21%. Among four studies of interrater reliability for five TrP diagnostic characteristics, untrained experienced examiners achieved unsatisfactory mean kappa values of 0.35 and 0.38, trained inexperienced examiners examiners a fai value of 0.49, and trained experience examiners a good mean kappa of 0.74. The highest mean kappa values were for spot tenderness, pain recognition, and palpable band [0.84-0.88]. A revision of previous injection technique more effectively inactivates the multiple active loci that are an essential part of a trigger point. Recent literature introduced two differing hypot...
A practical route for the characterization of zinc powder compacts with the aid of instrumented indentation and scratch tests

Abstract In the current investigation the microstructural and mechanical properties of zinc compacted pallets were investigated. The pallets were compacted to different normalized densities (81–93%) under different pressures of 150, 200 and 450 MPa, respectively. The effect of sintering the samples under inert environment at 378 °C was also studied. Instrumented nanoindentation tests were utilized to deduce the mechanical properties of the compacted pallets. Nanoscratch tests were employed to qualitatively measure the sample resistance to plastic deformation. It was observed that there are two mechanisms driving the improvement of the mechanical properties. One mechanism is due to recrystallization driven by the increasing dislocation density and the other mechanism is due to consolidation of the particles into a continuous network due to diffusion and grain growth under high temperature sintering. The results also reveal that the mechanical properties and densities of the tablets are not linearly proportional to the compaction pressure. Higher compaction pressures resulted in denser tablets with higher elastic modulus and hardness. Upon sintering the compacts soften but also form a solid network due to the neighboring particles diffusion. Therefore, the hardness value drops but the reduced modulus increases. Furthermore, the nanoscratch tests revealed that higher compaction pressure produce not only a more compacted tablet, but also a more homogeneous one.
Methionine sulfoximine in vivo modifies the tRNALys pool of developing rat brain.

: tRNA was extracted from brains of 3-, 8-, and 18-day-old rats that were injected intracerebrally, 45 min before death, with [3H]methyl methionine or [8-3H]guanosine, and intraperitoneally, 3 h before death, with l-methionine-dl-sulfoximine (MSO), a methylation-activating convulsant agent. Although there was no effect of age or of MSO on the per gram yield of tRNA, its specific radioactivity (dpm/A260) was highest at 3 days in both the control and the MSO groups. Age- and MSO-related changes in the tRNALys content of the brain tRNA pool were investigated by means of benzoylated DEAE- cellulose (BDC) and reverse-phase chromatography (RPC). BDC chromatography revealed tRNALys species in the brains of the MSO-treated animals that were absent in control brains. Of particular interest was the finding that differences in RPC-5 chromatographic mobility between control and MSO-tRNALys species were abolished by conversion to lysyl-tRNA, suggesting that the MSO-elicited change(s) in tRNALLys structure involved the binding site(s) for lysine. Two additional findings were made: (a) lysine acceptance by the [3H]methyl-labeled tRNALys purified from brains of the MSO-treated animals was higher than that of controls at 18 days; and (b) omission of the BDC chromatographic step accentuated the differences in mobility on RPC-5 columns between tRNALys species of control and MSO-treated brains. Lastly, we found that some tRNALys species present in the MSO-treated brains contained significantly different proportions of N2-methyl guanine and 1-methyl adenine, relative to controls. These MSO-elicited changes in the methyl base content of tRNALys of immature rat brain are the first evidence of an alteration of brain tRNA structure by a centrally acting excitatory agent.
Acceleration of Anisotropic Scattering Computations Using Coupled Ordinates Method (COMET)

Traditional sequential solution procedures for solving coupled heat transfer and radiation problems are known to perform very poorly when the optical thickness is high. This poor performance can be traced to the fact that sequential procedures cannot handle strong inter-equation coupling resulting from large absorption and scattering coefficients. This paper extends the use of the coupled ordinates method (COMET) to problems involving anisotropic scattering, where inter-equation coupling results from the in-scattering terms. A finite volume formulation for arbitrary unstructured meshes is used to discretize the radiative transfer equation. An efficient point-solution procedure is devised which is suitable for different scattering phase functions, and eliminates the cubic dependence of the operation count on the angular discretization. This solution scheme is used as a relaxation sweep in a multigrid procedure designed to eliminate long-wavelength errors. The method is applied to scattering problems and shown to substantially accelerate convergence for moderate to large optical thicknesses
C-reactive protein as a marker of severe calcification among patients with bicuspid aortic valve disease

Abstract Background. Bicuspid aortic valve (BAV) may be associated with aneurysmal dilatation of the ascending aorta, even after successful aortic valve replacement. There are as yet no biomarkers that correlate with the progression of such disease. Elevated levels of C-reactive protein (CRP), a marker of acute inflammation, are seen in chronic rheumatic valve disease, especially those with multivalvular disease, and have been shown to return to normal after valve replacement. We hypothesized that dilatation of the ascending aorta with BAV would be associated with ongoing inflammation, and, accordingly, elevated levels of CRP. Methods. High-sensitivity CRP levels [normal 0.02–0.8 mg/dl] were assayed from blood samples drawn in the operating room prior to cardiopulmonary bypass in 25 patients (4 female and 21 male, mean age 50 years, range 18–72 years) with bicuspid aortic valve disease undergoing valve replacement or repair. Preoperative cardiovascular risk factors for coronary artery disease, as well as valve function, area, and ascending aortic diameter based on echocardiogram were noted. Degree of valve calcification (none to minimal or moderate to severe) was recorded based on surgical observation or pathology report. None of the patients had active infections, tumors, or acute myocardial infarction. Results. There was no correlation of the CRP level to aortic diameter, valve area, patient age, gender, or body mass index (BMI). CRP levels were higher among patients with moderate-to-severe valvular calcification ( n = 13, mean 0.711 ± 2.22 mg/dl) compared with none or minimal valvular calcification ( n = 12, mean CRP 3.071 ± 5.62 mg/dl) ( P = 0.0065). This difference remained statistically significant after excluding patients with coronary artery disease ( n = 13). There was a trend for higher CRP level among patients with aortic stenosis (mean CRP 5.378 mg/dl) compared to those with aortic regurgitation (mean CRP 0.103 mg/dl) ( P = 0.058). Conclusions. Elevated CRP among patients with BAV did not correlate with aortic diameter, but was associated with advanced calcific valve disease. This assay may prove useful in understanding the pathogenesis of calcification in this group of patients and to identify those with BAV at risk for progressive aortic valve disease.
Spectral- and Pulse-Shape Discrimination in Triplet-Harvesting Plastic Scintillators

In this work, we describe a method to control the relative proportion of prompt and delayed luminosity of organic-based scintillators via direct and exponential emission from an extrinsic triplet state. This approach involves the incorporation of triplet-harvesting heavy metal complexes in plastic scintillator matrices to convert intrinsically non-luminescent host states to highly emissive guest states. Measurements on these plastic scintillators indicate improved light yields over the undoped polymers and the ability to perform neutron/gamma particle-discrimination. A similar extent of molecular-level control is not possible in traditional organic materials due to complex decay kinetics and the absence of spectral information for the delayed triplet-derived emission. The materials described here address these limitations through efficient host-guest triplet harvesting, which enables particle discrimination according to conventional pulse-shape discrimination (PSD) and a previously unreported spectral-shape discrimination (SSD) scheme.
A quadrupole ion trap/time-of-flight mass spectrometer with a parabolic reflectron

A matrix-assisted laser desorption/ionization-quadrupole ion trap/reflectron time-of-flight (MALDI-QIT/reTOF) mass spectrometer design and its operation in both normal and tandem mass spectrometric modes are described. A parabolic reflectron was found to be capable of providing mass resolution of 5000 for an initial ion energy distribution ranging over a 50% energy interval of the entire reflectron energy range. The sensitivity, ion isolation and fragmentation efficiency in the MALDI-QIT/reTOF instrument were close to those observed in the MALDI/QIT mass spectrometer. The mass resolution was shown to depend on the extraction field potentials, the r.f. trapping voltage amplitude and the phase of shutting down the r.f. voltage before extraction. At values of qz 0.4 is irregular but normally it is lower than that for ions having lower qz values. Mass spectral line positions shifted when the trapping voltage before extraction was varied. The line shifts were larger for lower mass ions and were comparable to the line widths in the case of very low masses. © 1998 John Wiley & Sons, Ltd.
T03-P-06 Evulvalution: portrayals of female genitalia across time and the current prepubescent ideal presented in mainstream men s magazines in the USA

Introduction Media depictions of the female body often inform women's conceptions of the societal ideal, serving as the gold standard for self-evaluation. Given the taboo surrounding display or discussion of female genitalia, these published images may be one of few sources of information regarding genital appearance that women encounter; consequently, any perceived physical deviation may be particularly disconcerting and compromise sexual satisfaction. The current study examined the portrayal of female genitalia within a mainstream men's magazine to characterize the prototype and its evolution across time. Design and Method Two independent raters conducted a content analysis of the centerfold pictorials (N=647) of a popular men's magazine featuring images of nude women for all monthly issues published between December 1953 and October 2007. The appearance of each centerfold model's external genitalia, including the color and visibility of her labia minora, as well as other physical and demographic characteristics were coded and analyzed. Results Despite medical evidence of wide variation in genital appearance within the general population, specific ideals were identifiable per era because of the homogeneity among images presented during each. An emerging trend towards nonexistent pubic hair and minimal visibility of the labia minora was found in recent photos that exposed the external genitalia. Conclusions Findings suggest that the genital ideal may be shifting farther away from the natural female form in favor of a prepubescent appearance. Accordingly, women's physical deviation from the prototype may become increasingly salient to them, which may have detrimental implications for their self-image and sexual satisfaction.
Critical decision making in the management of patients with acute myocardial infarction and other acute coronary syndromes.

Optimal management of a patient presenting to the emergency department (ED) with signs or symptoms suggestive of an acute coronary syndrome (ACS), including acute myocardial infarction (AMI), should be efficient and cost effective. The diagnosis and differential diagnosis should be established accurately and rapidly. The least expensive initial strategy might not be the most cost effective in the long run, however. For example, applying more costly diagnostic testing in the ED (such as cardiac nuclear imaging or exercise testing) to determine whether a patient can be discharged home with follow-up testing can add up-front cost but could well be the least expensive alternative if those costs are offset by a substantial decrease in the number of patients requiring unnecessary hospitalization. The purpose of this article is to describe and analyze the process by which critical decisions must be made in diagnosing and managing patients who present to the ED with signs or symptoms of an AMI or other ACS. Example cases are used to illustrate key steps in the decision-making process. In addition, several common pitfalls in clinical decision making will be pointed out.
Automated Concept Generation Using Branched Functional Models

This paper discusses a new concept generation technique that improves upon a previous automated concept generation theory and algorithm developed by Bryant, et al. at the University of Missouri – Rolla. The previous automated concept generation algorithm utilizes the design knowledge present in a repository to produce an array of partial concept solutions. While the previous algorithm is capable of handling branched functional models, it does not efficiently remove all of the infeasible partial solutions to leave only whole concepts in the final results. A matrix-based algorithm is presented in this paper that utilizes the result from the previous concept generation algorithm and solves for complete solutions of branched concepts. The presented algorithm eliminates incomplete and infeasible concepts or components from the results and generates a set of full solutions for further analysis by a designer. The details of the algorithm are described in this paper, and a peanut-sheller example is used to illustrate the effective use of the algorithm for producing branched concept variants.Copyright © 2010 by ASME