cssi/SciSciGPT-SciSciNet huggingface dataset:
An optimum supervisory system for paper production using distributed controls

Abstract A method for the control of basis weight by supervisory optimization is worked out. The objective is to determine the optimum supervisory machine speed and basis weight set point adjustments to maximize the profitability of production subject to the constraints of plant operation. The cost function consists of production cost and the loss due to rejects. An optimization scheme is worked out to calculate an optimization policy. Furthermore, the machine speed versus profit relations are developed to arrive at a supervisory machine speed that provides the globally minimized cost (maximized profit). The sampled measurements are processed to determine the variance and expected values of process variables. The expected values are used by the optimization system to determine the set point adjustments (corrections) by using the production and reject cost data. The supervisory machine speed is determined based on the optimum cost values of operation at various speeds to reach a globally minimum cost value. The implementation by distributed control systems is described, including the benefits of such a system.
Electromechanical comparison of cantilevered beams with multifunctional piezoceramic devices

Abstract This paper presents an electromechanical comparison of the transduction capabilities of a clamped-free Macro-Fiber Composite (MFC) actuated unimorph to other unimorphs employing monolithic piezoceramic devices. Four cantilevered unimorph beams, employing PSI PZT-5A, PSI PZT-5H, MIDE QP10N and MFC 8528-P1 type devices, are analyzed in the comparison. The unimorphs are evaluated for their actuation performance via tip displacement induced with harmonic voltage excitation, energy harvesting via electrical power output on a resistive shunt induced by harmonic base acceleration and linear feedback control effectiveness with the application of a Positive Position Feedback controller. The constitutive nonlinearities arising from large strain and electric field amplitudes are identified and briefly discussed. The MFC 8528-P1 type unimorph showed the highest mass-normalized actuation authority and the lowest energy harvesting capability.
Pharmacokinetic analysis of piperacillin administered with tazobactam in critically ill, morbidly obese surgical patients.

Study Objective To evaluate the steady-state pharmacokinetic and pharmacodynamic parameters of piperacillin in morbidly obese, surgical intensive care patients. Design Open-label single-center prospective study. Setting Level I trauma center and university-affiliated teaching institution. Patients Nine morbidly obese (body mass index [BMI] 40.0 kg/m2 or higher) hospitalized patients admitted to the trauma and surgical intensive care service who were treated with piperacillin-tazobactam between December 15, 2010, and April 18, 2012. Intervention Patients received intravenous piperacillin-tazobactam 4.5 g every 6 hours, administered as a 30-minute infusion. Measurements and Main Results Patients' blood samples were collected after the administration of the fourth, fifth, or sixth dose (i.e., at steady state). Serum piperacillin concentrations were determined by using a validated high-performance liquid chromatography assay; these concentrations were used to estimate pharmacokinetic parameters, and 5000-patient Monte Carlo simulations were performed. The probability of target attainment for 50% or higher of the dosing interval during which free (unbound) drug concentrations exceeded the minimum inhibitory concentration (%fT > MIC) of likely pathogens was calculated for piperacillin at various MICs. Patient demographic and clinical characteristics included a mean ± SD total body weight of 164 ± 50 kg, BMI of 57 ± 15.3 kg/m2, and age 57 ± 11 years, and a median Acute Physiology and Chronic Health Evaluation II score of 22 (interquartile range 21–26). Compared with values previously reported in other populations, the volume of distribution was increased in the study patients, and total system clearance was decreased. The net result was a mean ± SD half-life of 3.7 ± 1.2 hours compared with ~1 hour reported in other populations. This contributed to an extended %fT > MIC for likely pathogens. Results from all nine patients showed %fT > MIC of 100% at the susceptibility breakpoint MIC of 16 mg/L and 85% or higher at an MIC of 32 mg/L. Conclusion The pharmacokinetics of piperacillin is altered in morbidly obese, surgical intensive care patients. The use of standard-dosage piperacillin-tazobactam 4.5 g intravenously every 6 hours was shown to be an appropriate dosage for this study population.
Reduction of protein mixed disulfides (Dethiolation) by Escherichia coli thioredoxin: A study with glycogen phosphorylase b and creatine kinase

The role of thioredoxin in the reduction of protein mixed disulfides (dethiolation) was studied by electrofocusing methodology with glycogen phosphorylase b and creatine kinase as substrates for the reaction. Glycogen phosphorylase b was effectively dethiolated by Escherichia coli thioredoxin with dithiothreitol as the reductant, while creatine kinase could not be dethiolated by this mechanism. The rate of dethiolation of phosphorylase b was dependent on the concentration of thioredoxin up to a maximum at 20 microM when the concentration of phosphorylase b was 4 microM in monomer. Rat heart contained a thioredoxin reductase activity that could use added E. coli thioredoxin to dethiolate phosphorylase b and the same concentration of thioredoxin as above was required. This activity was not expressed with creatine kinase as the substrate. Cardiac tissue was shown to have a similar endogenous dethiolating activity. These results suggest that thioredoxin may play an important role in dethiolating specific proteins that might become S-thiolated during oxidative stress of cardiac tissue.
Ring array antenna with optimized beamformer for Simultaneous Transmit And Receive

In order to avoid self-interference, Simultaneous Transmit And Receive (STAR) systems require low mutual coupling between their respective transmit and receive antennas. This paper discusses the development of an 8-element transmit ring array antenna on a circular ground plane with a raised receive element. When combined with a beamformer that supplies linear progressive phase shifts to the array with opposing elements phased 180-degrees apart, the receive and transmit antennas are measured to exhibit 55 dB of isolation and omni-directional patterns in the 2.4 to 2.5 GHz band.
IRAS 15099 - 5856 and the composite supernova remnant G320.4 - 1.2

The supernova remnant (SNR) G320.4 - 1.2 is a composite SNR, containing both a shock-dominated shell, and a pulsar-dominated plerion. G320.4 - 1.2 is one of the few SNRs in which a pulsar has been detected. This paper reports on IRAS observations of this SNR. A pointlike source (IRAS 15099 - 5856) near the position of the pulsar appears quite prominently at 25 microns. The region appears more complex at 60 and 100 microns. Three models that may account for the IR emission of IRAS 15099 - 5856 are examined; none of these is entirely satisfactory. Some IR emission is detected from the brightest portion of the shell of this SNR, but this emission is nearly hidden by other confusing sources.
Effects of Chromium on Body Composition and Weight Loss

Chromium is an essential nutrient involved in the regulation of carbohydrate and lipid metabolism. Normal dietary intake of chromium in humans and farm animals is often suboptimal. In addition to its effects on glucose, insulin, and lipid metabolism, chromium has been reported to increase lean body mass and decrease percentage body fat, which may lead to weight loss in humans. The effects of chromium on body composition are controversial but are supported by animal studies, which increase their validity. A subject's response to chromium depends on his or her chromium status, diet consumed, type and amount of supplemental chromium, and study duration. There have been no confirmed negative effects of chromium in nutritional studies. Chromium is only a small part of the puzzle in the control of weight loss and body composition, and its effects, if present, will be small compared with those of exercise and a well-balanced diet.
Force response to electrical stimulation of canine skeletal muscles.

Abstract In previous papers by the authors ( J. Biomechanics 14 , 579 and 587) studies of the modulated over-the-skin stimulation of human subjects are reported. The stimulation efficiency is quantified by recording the external pull induced by muscle contraction. This study is undertaken to obtain comparative data on live dogs where direct measurements of the muscle pull is possible. Results from the over-the-skin stimulation tests are compared with those obtained where the electrodes are placed directly on the muscle. Load sharing in a muscle group is also investigated when the electrodes are placed at different locations over the skin. Results from experiments on 39 dogs are discussed and compared to those obtained from the tests on human subjects.
Comparison of transfer ribonucleic acid aminoacylation by various regions of chicken brain.

Aminoacylation of tRNA with valine was greater in the cerebrum of chicken than the cerebellum or optic lobes. This greater aminoacylation was due to both the activity of the cerebral valyl-tRNA synthetases and the accepting activity of the cerebral tRNAval.
Transmission electron microscope studies on Li-doped MgO

Abstract Transmission electron microscope investigations of as-grown Li-doped MgO have revealed the presence of precipitates with an average size of 220 A. Detailed micro-diffraction studies and moire pattern analyses have identified these precipitates as Li2O with the cubic fluorite structure. Exposures of Li-doped MgO crystals either to high temperatures in air for 10 min followed by quenching or to a large dose of ionizing radiation at ambient temperature leads to a reduction in the precipitate size. These results lend support to our previous conjecture from optical and magnetic resonance studies that localized lithium-rich environments are responsible for the stable [Li]0 centres and that the source of these lithium ions are the precipitates.
Today's Top 30 Flow Assurance Technologies: Where Do They Stand?

The purpose of this paper is to provide conclusions from an extensive evaluation of all known state-of-the art flow assurance methodologies. The various technologies were assessed by maturity level (i.e. embryonic, emerging, matured or aging), applicability, solution type and their effectivity. Effectivity is a function of ease of application, probability of success and cost effectiveness. Within this study, the solutions were classified into thermal, chemical, hardware, operating and software technologies.
Narrative Review: Electrocution and Life-Threatening Electrical Injuries

The authors reviewed the mechanisms and pathophysiology of typically encountered electrical injuries by searching English-language publications listed in MEDLINE and reference lists from identified articles. They included relevant retrospective studies, case reports, and review articles published between 1966 and 2005. The authors also searched the Internet for information related to electrocution and life-threatening electrical injuries. They found that familiarity with basic principles of physics elucidates the typical injuries sustained by patients who experience electrical shock. Death due to electrocution occurs frequently. However, patients successfully resuscitated after cardiopulmonary arrest often have a favorable prognosis. Approximately 3000 patients who survive electrical shock are admitted to specialized burn units annually. Patients with serious electrical burns admitted to the intensive care unit are trauma patients and should be treated accordingly. Initial prediction of outcome for patients who have experienced electrical shock is difficult, as the full degree of injury is often not apparent.
A General ANOVA Method for Robust Tests of Additive Models for Variances

Abstract Linearly combining Levene's z 2 variable with the jackknife pseudo-values of s 2 produces a family of variables that allows for analysis of variance (ANOVA) tests of additive models for the variances in fixed effects designs. Some distributional theory is developed, and a new robust homogeneity of variance test is advocated.
Functional reconstitution of protein ion channels into planar polymerizable phospholipid membranes.

We demonstrate that polymerizable planar membranes permit reconstitution of protein ion channels formed by the bacterial toxins Staphylococcus aureus α-hemolysin (αHL) and Bacillus anthracis protective antigen 63. The αHL channel remained functional even after membrane polymerization. Surface pressure measurements suggest that the ease of forming membranes depends on membrane surface elasticity estimated from Langmuir−Blodgett monolayer pressure−area isotherms. The ability to stabilize nanoscale pores in robust ultrathin films may prove useful in single molecule sensing applications.
Erratum to Youth self-report of physical and sexual abuse: A latent class analysis [Child Abuse & Neglect 34 (2010) 146―154]

a Department of Psychology, Montclair State University, Montclair, NJ, USA b Department of Psychology, San Diego State University and SDSU/UCSD Joint Doctoral Program in Clinical Psychology, San Diego, CA, USA c Juvenile Protective Association, Chicago, IL, USA d School of Public Health, University of North Carolina, Chapel Hill, NC, USA e School of Social Work, University of Washington, Seattle, WA, USA f Department of Social Medicine, University of North Carolina School of Medicine, Chapel Hill, NC, USA g Department of Psychiatry, University of North Carolina School of Medicine, Chapel Hill, NC, USA
Hormonal regulation of dopa decarboxylase during a larval molt.

Abstract Cuticular sclerotization in insects requires dopamine derivatives and thus the presence of dopa decarboxylase (DDC), the enzyme which converts dopa to dopamine. During the last half of the larval molt of the tobacco hornworm, Manduca sexta, beginning at 16 hr after head capsule slippage, the epidermal DDC activity increased fourfold. By contrast, allatectomized larvae which were destined to produce a melanized cuticle showed a sevenfold increase. This increase in DDC activity was prevented by infusion of 20-hydroxyecdysone (20HE) into the larva, indicating that the fall of the ecdysteroid titer is necessary for the increase. In vitro 20HE also prevented the increase in a dose-dependent manner when the epidermis was explanted at 16 hr after head capsule slippage but had less effect on epidermis explanted 3 hr later. Both 5 μg/ml α-amanitin and 100 μg/ml cycloheximide also prevented the increase. Application of juvenile hormone I showed that the critical period for determination of the level of the later increase in DDC activity was about 4 hr after head capsule slippage at the peak of the ecdysteroid titer. Apparently then the rise and fall of ecdysteroid regulate different aspects of DDC synthesis, the rise determining its later appearance and the fall timing this appearance.
Humoral Thymic Factor in Mice: Further Evidence

Mice of the C3H and DBA strains thymectomized at birth showed a consistent and striking suppression of antibody production (hemolysin response) to sheep erythrocytes. When cell-tight Millipore diffusion chambers containing syngeneic thymic tissue were implanted intraperitoneally, the capacity of these neonatally thymectomized mice to respond to this antigen was restored. The pattern of response and the mean titer were similar to the pattern and mean titer observed in neonatally thymectomized mice bearing subcutaneous grafts of syngeneic thymic tissue. These data are consistent with the concept that thymic tissue within the chamber produced a specific diffusible factor that enabled the thymectomized animal to establish immunologic competence.
Facial muscle activity and EEG recordings: redundancy analysis

Abstract The present study ecplored the use of redundancy analysis, a multivariate technique for assessment of interset association, to examine facial muscle contamination of EEG recordings in studies involving covert levels of emotional expression. Redundancy analyses were performed on simultaneously recorded EEG and facial EMG data obtained in an emotion induction paradigm. Redundancy indices obtained suggest that (1) the amount of variance in EEG activity that can be explained by facial muscle activity under such conditions is minimal, and (2) the EEG alpha band may be at least as or even more susceptible to muscle contamination as the beta band.
MICRO-INTERACTIONAL CONSTRUCTIONS OF POWER AND IDENTITY

This issue examines how micro-interactional processes contribute to constructions of identity and power in face-to-face interactions. In using the term “power,” we are specifically talking about id...
Lower esophageal rings as a cause of dysphagia in progressive systemic sclerosis--coincidence or consequence?

Lower esophageal rings were found in five of 40 consecutive patients seen with progressive systemic sclerosis. Three of these five patients had diffuse skin involvement and two had the CREST variant of progressive systemic sclerosis. All of the patients with lower esophageal rings had intermittent esophageal obstruction (initially attributed to esophageal dysmotility), but so did five of seven patients with esophageal strictures without lower esophageal rings. Esophageal bougienage relieved this symptom in four of the five patients with rings in which it was performed. Persistent relief of these obstructive symptoms (6–36 months) in the patients with rings was in contrast to the recurrent dilatations that have been needed in the group of patients with peptic strictures. In contrast to esophageal aperistalsis and/or stricture formation, the lower esophageal ring, perhaps as a consequence of chronic gastroesophageal reflux, may be a more treatable cause of dysphagia in patients with progressive systemic sclerosis.
Nonoperative management of blunt renal injury: a need for further study.

Abstract Background Blunt renal injury in children is usually managed without an operation. However, there are no published guidelines for nonoperative management. Therefore, we conducted a retrospective review to examine the natural history of these injuries and to identify potential recommendations for management. Methods A retrospective analysis of our most recent 12-year experience with blunt renal injury was performed. Results One hundred eleven trauma patients were identified as having a renal injury. Mean age was 10.8 ± 4.4 years with a weight of 43.1 ± 20.8 kg and 65% of the patients were males. In patients with an isolated renal injury (n = 65), the mean length of bed rest was 3.8 ± 1.9 days, resulting in a mean length of hospitalization of 3.8 ± 3.1 days. There were no transfusions, and the only operation for renal trauma was a nephrectomy in a patient with existing end-stage obstructive nephropathy of that kidney. There were 15 patients discharged with persistent hematuria, none of which had long-term sequelae. Conclusion Our data suggest the risk of significant injury from blunt renal trauma is low, and clearance of hematuria is not likely an important parameter such that bed rest with serial blood and urine monitoring may not be justified. There is clearly a role for the prospective application of a more liberal management protocol.
Decay widths and scattering processes in massive QED2

Abstract Using mass perturbation theory, we infer the bound-state spectrum of massive QED 2 and compute some decay widths of unstable bound states. Further, we discuss scattering processes, where all the resonances and particle production thresholds are properly taken into account by our methods.
Transformations between random networks and dense random-packed models for amorphous solids

Random network models used in describing a covalently bonded material such as amorphous silicon or germanium can be transformed to a dense random-packed model used in describing metallic amorphous ...
Glioblastoma in Children

Both morphologic and clinical features of 72 consecutive cases of brain tumors, collected over 9 years at Le Bonheur Children's Medical Center, were reviewed. We identified 11 cases as glioblastoma, representing 16% of all intracranial neoplasm and 26% of glial tumors. The patients ranged in age from 1 to 15 years with the median age of 10 years. There were 4 females and 7 males; 2 blacks and 9 whites. The median survival was 9 months. The tumor was observed in both cerebrum and cerebellum. Sexual predominance was not appreciable, although there was male excess. The tumor was significantly more frequent in whites than blacks (p < 0.05). Similar racial predominance was noted in the other, more common brain tumors in children such as astrocytoma and medulloblastoma.
The Lithium−Sodium−Methylamine System: Does a Low-Melting Sodide Become a Liquid Metal?

The properties of the simplest sodide, LiNa(CH3NH2)n, are reported as a function of n. The phase diagram, established by using differential thermal analysis, shows the presence of a compound with n ≈ 6, which melts congruently at 168.5 ± 0.5 K. Two eutectics are present with n = 7.3 ± 0.3, T1 = 166 ± 1 K and n = 3.0 ± 0.2, T2 = 151 ± 1 K. The phase diagram was extended to metal concentrations that correspond to n = 1.45 and indicated the presence of a second compound with 2 ≤ n ≤ 3. The properties of these systems were investigated by EPR and alkali metal NMR spectroscopies and static magnetic susceptibilities. The 23Na NMR results clearly show that sodium is present as Na- for n ≥ 8. At higher metal concentrations the resonance line shifts smoothly toward more paramagnetic values (positive), with larger shifts at higher temperatures. EPR spectroscopy shows a transition from a single nearly symmetric line at large values of n to a strongly asymmetric signal characteristic of conduction electron spin reson...
Knowledge assets in the global economy: assessment of national intellectual capital

This article has the following objectives: developing the need for assessing knowledge capital at the national economic level; review of a national case study of how intellectual capital assessment was done in case of one nation state; suggesting implications of use of such assessment methods and needed areas of advancement; and highlighting caveats in existing assessment methods that underscore the directions for future research. With increasing emphasis on aligning national information resource planning, design and implementation with growth and performance needs of businesses or nations, better understanding of new valuation and assessment techniques are necessary for information resource management policymakers, practitioners and researchers.
A novel cache distribution heuristic algorithm for a mesh of caches and its performance evaluation

The widespread use of the Internet has created two problems: document retrieval latency and network traffic. Caching of documents 'close' to users has helped alleviate both problems. Different caching policies have been proposed/implemented to make best use of limited available cache at each caching server. A mesh of caching servers, aided by different data diffusion algorithms and the natural hierarchical structure of the Internet topology, has increased 'virtual' size of cache. Yet the size of available cache is small compared to the total size of all documents served, and remains a major resource constraint. In this work, we looked at how to improve document download time, by distributing a fixed amount of total storage in a network or mesh of caches. The intuition behind our cache distribution approach is to give more storage to the caching nodes in the network, which experience more traffic, in the hope that this will reduce the average latency of document retrieval in the network. A heuristic was developed to estimate traffic at each cache of a network. From this traffic estimation, each cache then receives a corresponding percentage of the total storage capacity of the network. Through extensive simulation it is found that the proposed cache distribution algorithm can reduce latency up to 80% over prior work that includes both Harvest-type and demand-driven data diffusion algorithms. Furthermore, the best improvement was achieved in a cache range that corresponds to practical, real world cache ranges.
Oncogenic KRAS promotes malignant brain tumors in zebrafish

Zebrafish have been used as a vertebrate model to study human cancers such as melanoma, rhabdomyosarcoma, liver cancer, and leukemia as well as for high-throughput screening of small molecules of therapeutic value. However, they are just emerging as a model for human brain tumors, which are among the most devastating and difficult to treat. In this study, we evaluated zebrafish as a brain tumor model by overexpressing a human version of oncogenic KRAS (KRASG12V). Using zebrafish cytokeratin 5 (krt5) and glial fibrillary acidic protein (gfap) gene promoters, we activated Ras signaling in the zebrafish central nervous system (CNS) through transient and stable transgenic overexpression. Immunohistochemical analyses were performed to identify activated pathways in the resulting brain tumors. The effects of the MEK inhibitor U0126 on oncogenic KRAS were evaluated. We demonstrated that transient transgenic expression of KRASG12V in putative neural stem and/or progenitor cells induced brain tumorigenesis. When expressed under the control of the krt5 gene promoter, KRASG12V induced brain tumors in ventricular zones (VZ) at low frequency. The majority of other tumors were composed mostly of spindle and epithelioid cells, reminiscent of malignant peripheral nerve sheath tumors (MPNSTs). In contrast, when expressed under the control of the gfap gene promoter, KRASG12V induced brain tumors in both VZs and brain parenchyma at higher frequency. Immunohistochemical analyses indicated prominent activation of the canonical RAS-RAF-ERK pathway, variable activation of the mTOR pathway, but no activation of the PI3K-AKT pathway. In a krt5-derived stable and inducible transgenic line, expression of oncogenic KRAS resulted in skin hyperplasia, and the MEK inhibitor U0126 effectively suppressed this pro-proliferative effects. In a gfap-derived stable and inducible line, expression of oncogenic KRAS led to significantly increased mitotic index in the spinal cord. Our studies demonstrate that zebrafish could be explored to study cellular origins and molecular mechanisms of brain tumorigenesis and could also be used as a platform for studying human oncogene function and for discovering oncogenic RAS inhibitors.
Circadian blood pressure classification scheme and the health of patients with chronic kidney disease.

Background: In health, a sinusoidal rhythm is observed in systolic blood pressure (BP) that peaks (acrophase) during the waking hours (in-phase), but in those with chronic kidney di
Pre-slow roll initial conditions: large scale power suppression and infrared aspects during inflation

If the large scale anomalies in the temperature power spectrum of the cosmic microwave background are of primordial origin, they may herald modifications to the slow roll inflationary paradigm on the largest scales. We study the possibility that the origin of the large scale power suppression is a modification of initial conditions during slow roll as a result of a pre-slow roll phase during which the inflaton evolves rapidly. This stage is manifest in a potential in the equations for the Gaussian fluctuations during slow roll and modify the power spectra of scalar perturbations via an initial condition transfer function T (k). We provide a general analytical study of its large and small scale properties and analyze the impact of these initial conditions on the infrared aspects of typical test scalar fields. The infrared behavior of massless minimally coupled test scalar field theories leads to the dynamical generation of mass and anomalous dimensions, both depend non-analytically on T (0). During inflation all quanta decay into many quanta even of the same field because of the lack of kinematic thresholds. The decay leads to a quantum entangled state of sub and superhorizon quanta with correlations across the horizon. We find the modifications of the decay width and the entanglement entropy from the initial conditions. In all cases, initial conditions from a “fast-roll” stage that lead to a suppression in the scalar power spectrum at large scales also result in a suppression of the dynamically generated masses, anomalous dimensions and decay widths.
Molar microwear and diet in large carnivores: inferences concerning diet in the sabretooth cat, Smilodon fatalis

Patterns of dental microwear provide some of the best indirect evidence of tooth use and diet in living and extinct species, and thus can supplement inferences based on gross morphology. In this paper, dental microwear features are examined in the extinct sabretooth cat Smilodon fatalis and among eight species of extant large carnivores, including felids, canids, hyaenids and a mustelid. Although all the living species are primarily carnivorous, some differ in the relative quantities of large bones consumed; hyaenas are the most frequent bone-crushers and cheetahs the least. Because bone is harder than meat, interspecific differences in bone consumption are expected to be reflected by differences in microwear pattern. Scanning electron micrographs of the wear facet of the lower first molar (carnassial) were used to estimate the average density, size, shape and orientation of microwear features for each species. Results indicate that dietary differences are highlighted when features shorter than 30 μm in length are excluded from the analysis. When this is done, hyaenas are distinguished from other species by a combination of relatively few long features and a high proportion of pits to scratches. By contrast, the cheetah is characterized by a predominance of narrow features, relatively few of which are pits. Species of intermediate diet, such as the wolf, leopard, wild dog and wolverine, tend to be intermediate in pit density and feature shape. Comparisons of the carnivore microwear data with that published for primates reveal that the eight carnivores are most similar to frugivorous primates that specialize on relatively hard fruits. In addition, the orientation of microwear features is significantly more variable in carnivores than in the only comparably studied primate, the chimpanzee. This suggests that many of the microwear features on the carnassial are produced by food moving in directions other than occlusal pathways. The pattern of microwear features in the sabretooth cat is distinct from all of the sampled extant carnivores. Smilodon has relatively narrow, long features and an extremely low pit frequency. Thus Smilodon probably consumed less bone than does the cheetah and may have left behind significant amounts of bone and meat for scavengers. The sabretooth cat may have avoided bone in order to protect its long canines from breakage.
Efficient implementation of the Fourier dual reciprocity boundary element method using two-dimensional fast Fourier transforms

Abstract The Poisson equation is one of the field equations which arises often in aerospace applications, and its efficient solution is of great importance to aerodynamic studies. The boundary element method (BEM) is a powerful method for the solution of such field problems as it reduces the dimension of the problem by one and leads to boundary only discretization for linear problems without distributed source/sink terms. The Fourier Dual Reciprocity Boundary Element Method (FDRBEM) was developed to retain the boundary only discretization character of the BEM. The basis of the method is the expansion of the generation term in a two-dimensional Fourier series which is in turn used to transform the BEM area integrals into contour integrals. In this paper, a two-dimensional Fast Fourier Transform (FFT) algorithm is developed to efficiently and accurately extract the Fourier coefficients of the two-dimensional series expansion of the source term. Practical concerns in the implementation of the FDRBEM are discussed. Four numerical examples are presented to validate the approach.
Effects of Three Refrigerants on the Interior Quality and Functional Properties of Shell Eggs

ABSTRACT INTRODUCTION COMMERCIAL short-term storage of shell eggs is a common practice. In many instances eggs are in storage for several months under refrigeration, and it is not uncommon for refrigeration systems to break down or for leaks to occur in the systems. This study was undertaken to establish what effects three of the most common refrigerants, namely, freon 11, freon 12, and ammonia gas, would have on the interior quality and functional properties of shell eggs. Known concentrations of each gas were applied to shell eggs for a 24-hour period before testing. LITERATURE REVIEW Freon 11 (trichloromonofluoromethane) and freon 12 (dichlorodifluoromethane) are chemically inert, of low toxicity, nonflammable, colorless, and, in concentrations under 20 percent in air, are odorless. Freon 11 is used widely in industrial and commercial refrigeration as is freon 12, but freon 12 is more often used in household refrigerators and also as an aerosol propellent, either . . .
Combination of inhibition of thrombin and blockade of thromboxane A2 synthetase and receptors enhances thrombolysis and delays reocclusion in canine coronary arteries.

BACKGROUNDThe efficacy of thrombolytic therapy in treating patients with acute myocardial infarction is limited by failure to achieve reperfusion in some patients, by the prolonged time required to achieve reperfusion, and by reocclusion of some coronary arteries. We designed this study to examine the effect of combined inhibition of thrombin and thromboxane synthesis and blockade of thromboxane A2 receptors in addition to tissue-type plasminogen activator (t-PA) on thrombolysis and reocclusion in an experimental canine model with coronary thrombosis.METHODS AND RESULTSBlood flow velocity in the left anterior descending coronary artery (LAD) of 32 anesthetized mongrel dogs was monitored by a pulsed Doppler flow probe. Coronary thrombosis was induced by applying electrical stimulation to the LAD at the site where an external constrictor was used to narrow the artery. Three hours after the formation of occlusive thrombus, animals were randomly assigned to receive one of the following: 1) t-PA (80 micrograms...
Assessment of video display workstation set up on risk factors associated with the development of low back and neck discomfort

Abstract Approximately 33% of visual display terminal (VDT) operators report back and neck pain annually. As a result, a number of “ergonomic” chairs have been developed ranging the price spectrum. The objectives of this study were to (1) assess the effects of monitor height and chair type on low back and neck muscle activity, perceived level of discomfort (PLD), and posture shifts; and (2) determine if chairs at opposing ends of their price spectrum differ in the physiological benefits. Two levels of monitor height and chair type were assessed. The findings of this research indicate that the interaction of monitor height and chair type significantly affects the loads placed on the human body. Task demands also play an important role in the loads placed on the body, posture fixity, and level of discomfort reported. Therefore, the location of VDT equipment and chair selection should be based on task demands to minimize static loading and discomfort. In general, no gross physiological differences were identified between high and low cost chairs, again supporting the recommendation that chair selection be based on task demands. Relevance to industry This research assesses differences in high and low cost ergonomic chairs as they relate to physiological responses of the back and neck and user perceived discomfort. This information can be used to guide organizations in the purchase of office equipment.
Hypoxia induces angiogenic factors in brain microvascular endothelial cells

Hypoxia is increasingly recognized as an important contributing factor to the development of brain diseases such as Alzheimer's disease (AD). In the periphery, hypoxia is a powerful regulator of angiogenesis. However, vascular endothelial cells are remarkably heterogeneous and little is known about how brain endothelial cells respond to hypoxic challenge. The objective of this study is to characterize the effect of hypoxic challenge on the angiogenic response of cultured brain-derived microvascular endothelial cells. Brain endothelial cell cultures were initiated from isolated rat brain microvessels and subjected to hypoxia (1% O(2)) for various time periods. The results showed that hypoxia induced rapid (≤ 0.5h) expression of hypoxia-inducible factor 1α (HIF-1α) and that cell viability, assessed by MTT assay, was unaffected within the first 8h. Examination of brain endothelial cell cultures for pro- and anti-angiogenic proteins by western blot, RT-PCR and ELISA revealed that within 0.5 to 2h of hypoxia levels of vascular endothelial growth factor and endothelin-1 mRNA and protein were elevated. The expression of heme oxygenase-1 also increased but only after 8h of hypoxia. In contrast, similar hypoxia exposure evoked a decrease in endothelial nitric oxide synthase and thrombospondin-2 levels. Exposure of brain endothelial cell cultures to hypoxia resulted in a significant (p<0.001) decrease (94%) in tube length, an in vitro index of angiogenesis, compared to control cultures. The data indicate that, despite a shift toward a pro-angiogenic phenotype, hypoxia inhibited vessel formation in brain endothelial cells. These results suggest that in brain endothelial cells expression of angiogenic factors is not sufficient for the development of new vessels. Further work is needed to determine what factors/conditions prevent hypoxia-induced angiogenic changes from culminating in the formation of new brain blood vessels and what role this may play in the pathologic changes observed in AD and other diseases characterized by cerebral hypoxia.
Molecular basis of fertilization in the mouse

Abstract Recent studies of mouse fertilization have identified two complementary gamete receptors that mediate sperm-egg binding. Sperm surface β1,4-galactosyltransferase (GalTase) binds to specific oligosaccharides of the egg coat (zona pellucida) glycoprotein ZP3. Evidence suggests that these same molecules may stimulate the acrosome reaction in sperm. After the acrosome reaction, it is thought that sperm remain adherent to the zona by binding another glycoprotein, ZP2. The acrosome-reacted sperm releases hydrolytic enzymes, including acrosin and N-acetylglucosaminidase, enabling it to penetrate the zona pellucida. After the penetrating sperm binds to the egg membrane and activates development, N-acetylglucosaminidase is exocytosed from egg cortical granules and, as part of the zona block to polyspermy, globally removes the sperm GalTase binding site from ZP3 oligosaccharides.
Body Image, Acculturation, and Substance Abuse Among Boys and Girls in the Southwest

This study explored body image as measured by perceptions of weight and appearance and its impact on adolescent drug use among predominately Mexican American middle school students in the southwest. Outcomes analyzed included lifetime and recent alcohol, cigarette, and marijuana use and antidrug norms. Disliking one's looks was more of a risk factor for boys, whereas negative weight perceptions were more of a risk factor for girls. Relative to more acculturated (English-dominant) Latinos (N = 903), non-Latino Whites (N = 121), and other non-Latino youth (N = 107), less acculturated (Spanish-dominant) Latino youth (N = 212) reported the poorest body image. However, more acculturated Latino youth with poor body image had the greatest risk of substance use. More acculturated Latino boys who disliked their looks reported relatively greater amounts of recent alcohol use, and those who rated their bodies as too thin reported higher lifetime cigarette use, a greater amount and frequency of recent cigarette use, ...
The Effect of Dye Structure on Order Parameter in a Nematic Liquid Crystalline Host1

Abstract The order parameters (S) of a number of substituted azobenzenes and phenylazothiazole, -benzothiazole and -heterocyclic compounds dissolved in a nematic liquid crystalline host have been determined. The measured order parameters for a class of azo compounds bear a strong relationship to the structure of the dye. For azobenzenes, there is an additivity of substituent effects which leads to good agreement between empirically-derived and observed S values. Disazo dyes give higher S values than the corresponding monoazo dyes. For heterocyclic phenylazo dyes, the end group substituents on the phenyl ring play a significant role in influencing S, whereas the nature of the heterocyclic system, as well as the end group substituents on the heterocyclic ring, are only of minor importance. The presence of an N-H moiety as part of a heterocyclic ring, or the fusion of a benzene ring onto a heterocyclic ring, can lead to significant changes in the order parameter.
Analytical studies of contact of nominally flat surfaces - Effect of previous loading

Previous plastic loading deformation effect on contact area, print number, size distribution and thermal conductivity for flat surfaces
Generation and Gender: Normative and Covert Hierarchies

This essay argues that gender is an irreducible category of clinical observation and theorizing, as crucial to the family therapy paradigm as the concept of "generation." Gender, therefore, is not a secondary, mediating variable like race, class, or ethnicity, but, rather, a fundamental, organizing principle of all family systems. The author analyzes the history and politics of family therapy in order to explicate how gender, as a co-equal concept, was erased as a universal principle of family organization, leaving only generation. The theoretical and clinical implications of situating gender at the center of family therapy are then discussed.
Finding their way on: Career decision‐making processes of urban science teachers

This article reports on a research study investigating the career decision-making processes of urban science teachers as one element central to understanding the high rates of attrition in the field. Using a longitudinal, prospective, context- and subject-specific approach, this study followed the career decisions of case study teachers over a period of 12 months. All eight of the case study teachers envisioned themselves eventually moving out of classroom teaching positions. Each used an ongoing and active process of decision making to evaluate their professional direction and sought confirmation of their contribution to the field before moving into new roles and responsibilities. This article describes the experiences of several teachers who exemplify these decision-making processes. These cases suggest potential benefits for differentiated roles, professional mentoring, and recognition and feedback from professional communities. © 2009 Wiley Periodicals, Inc. Sci Ed93:1096–1121, 2009
INTRAMOLECULAR HYDROGENATION OF ARYLOXIDE LIGANDS AT NIOBIUM METAL CENTERS: STEREOCHEMICAL CONSEQUENCES OF REACTION REGIOCHEMISTRY

The sodium amalgam reduction (2Na per Nb) of hydrocarbon solutions of the niobium compounds [Nb(OC6H3Ph2-2,6)3Cl2], 2a (OC6H3Ph2-2,6 = 2,6-diphenylphenoxide) and [Nb(OC6H2Ph3-2,4,6)3Cl2], 2b (OC6H2Ph3-2,4,6 = 2,4,6-triphenylphenoxide) under 1 atm of H2 leads to the deep-red, η4-cyclohexadiene complexes [Nb(OC6H3Ph-η4-C6H7) (OC6H3Ph2-2,6)2], 3a and [Nb(OC6H2Ph2-η4-C6H7)(OC6H2Ph3-2,4,6)2], 3b, respectively. The spectroscopic properties of 3a and 3b are consistent with one of the aryloxide ligands having undergone 1,2-hydrogenation of an ortho-phenyl substituent, leading to a cyclohexadiene group which is strongly coordinated to the metal center. This is confirmed by a single crystal X-ray diffraction analysis of 3a, showing the coordination sphere about niobium to consist of two, normal 2,6-diphenylphenoxide ligands and one chelating, partially hydrogenated aryloxide group. The η4-bonding of the chelated cyclohexadiene group is slightly distorted with NbC distances of 2.27(1), 2.27(2), 2.37(1) and 2.40(1) A. Hydrocarbon solutions of 3a and 3b will react further with hydrogen (200–1200 psi) to produce upon hydrolysis 2-cyclohexyl-4-phenylphenol and 2,6-dicyclohexylphenol (for 3a) and 2-cyclohexyl-4,6-diphenylphenol and 2,6-dicyclohexyl-4-phenylphenol (for 3b). The intra-molecular hydrogenation of aryl-phenoxide groups can also be achieved by treating mixtures of the chloride compounds [Nb(OC6H3Ph2-2,6)nCl5−n] or [Nb(OC6HPh4-2,3,5,6)nCl5−n] (n = 2,3) with (5 − n) equivalents of BunLi under hydrogen. Spectroscopic (1H, 13C NMR) analysis of the phenols obtained in all cases indicated that exclusive hydrogenation of ortho-phenyl groups occurs with no evidence of attack on either the meta- or para-phenyl substituents or upon the central phenoxy ring. The use of D2 as reagent gas leads to dicyclohexylphenols containing up to 11 deuterium atoms per cyclohexyl ring due to the presence of H/D exchange processes. Analysis of the stereochemical positions of the remaining protons in the cyclohexyl rings indicates that the hydrogenation of the phenyl rings occurs via two regiochemically distinct reaction pathways. Crystal data at 183 K for NbCl3O2C72H54, 1c: [Nb(OC6HPh4-2,3,5,6)2Cl3]·2C6H6, a = 12.561(2), b = 13.810(3), c = 17.836(3) A, α = 87.37(1), β = 72.63(1), γ = 76.85(1)°, Z = 2 in space group P1; at 294 K for NbO3C36H50, 3a: [Nb(OC6H3Ph-η4-C6H7)(OC6H3Ph2)2]·C7H7, a = 9.339(1), b = 13.107(1), c = 20.681(2) A, α = 93.807(8), β = 94.109(9), γ = 105.992(9)°, Z = 2 in space group P1. The trichloride compound 1c adopts a square pyramidal geometry about the mononuclear niobium metal center with one axial and one basal aryloxide ligand.
The Biogeochemistry of an Ombrotrophic Bog: Evaluation of Use as an Archive of Atmospheric Mercury Deposition

Abstract The utility of ombrotrophic bogs as archives of atmospheric mercury deposition was assessed with an investigation in Arlberg Bog, Minnesota, U.S.A. Since the use of ombrotrophic bogs as archives depends on the immobility of deposited trace metals, we examined the postdepositional transport processes revealed by the solid-phase distributions of mercury and ancillary metals (Fe, Al, Mn, and Pb) in this bog. We modeled metal speciation in bog porewaters as a function of pe in order to understand metal behavior in ombrotrophic peat. Specifically, we considered the effect of water movement and resultant shifts in redox potential gradients on metal retention. Our results indicate that Hg and Pb are immobile in ombrotrophic peat, so their distribution can be used to determine temporal changes in deposition. To substantiate the deposition estimates determined in this study, we emphasized the importance of confirming the validity of the dating scheme, assessing the degree of horizontal homogeneity in the accumulation record, and providing evidence for retention of Hg based on geochemical modeling. As recorded in Arlberg Bog, historic atmospheric Hg deposition increased gradually after the mid-1800s, peaked between 1950 and 1960, and may have declined thereafter. Preindustrial deposition was about 4 μg/m2year and recent deposition about 19 μg/m2year. The results of this study indicate that deposition at Arlberg Bog has been influenced by a regional and/or local-scale source.