cssi/SciSciGPT-SciSciNet huggingface dataset:
Spin-orbit splitting of GaAs and InSb bands near Γ

An ab initio pseudopotential calculation is used to examine the spin-orbit splitting of states in the zinc-blende semiconductors GaAs and InSb within the local-density approximation (LDA). The relativistic pseudopotentials are generated with the occupied d orbitals of the atoms in the rigid core. No correction is made to the calculated band gaps even though they are too small as a result of the LDA, resulting in a semimetal for InSb. These two features differ from an earlier ab initio linear muffin-tin orbitals (LMTO) calculation in which mixing of the d core states was included and the gap was corrected empirically. We examine the spin-orbit splitting of the valence bands at point \ensuremath{\Gamma}, and the linear-in-\ensuremath{\Vert}k\ensuremath{\Vert} splitting and mixing of the upper valence bands for the [100], [111], and [110] directions in a small region around point \ensuremath{\Gamma}. This provides a detailed calculation of the splitting and mixing of the light- and heavy-hole valence bands in the region of near-degeneracy. We also examine the linear and cubic terms away from point \ensuremath{\Gamma} in the [110] direction where the light and heavy holes are separated in energy and do not intermix appreciably. The spin-orbit splittings and linear-in-\ensuremath{\Vert}k\ensuremath{\Vert} valence-band splittings are in excellent agreement with the LMTO calculation and with experiment; however, an error in earlier analyses regarding the relative sign of two linear terms is found. The cubic terms are, for the most part, not accurate, which is expected from a local-density-functional calculation.
Components of the multifactor complex needed for internal initiation by the IRES of hepatitis C virus in Saccharomyces cerevisiae

Interaction between the 40S ribosomal subunit and the IRES of hepatitis C virus (HCV) is thought to be independent of initiation proteins, while joining of the 60S ribosomal subunit, and initiation of translation is dependent upon components of the translation machinery. An established in vivo functional assay for internal initiation mediated by the HCV IRES was used to identify proteins needed for IRES dependent translation in Saccharomyces cerevisiae strains possessing alterations of the translation machinery. Internal initiation dependent upon the HCV IRES was abrogated in strains lacking eIF5B, and reduced in strains with altered eIF3, either lacking the Hcr1p subunit, a component of eIF3 not previously known to interact with HCV RNA, or possessing an amino acid change in the Rpg1p subunit. The HCV RNA-induced conformational change in the 40S subunit might affect positioning of eIF3 and lead to different interactions between the ribosome, eIF3, and the multifactor complex. HCV IRES dependent initiation was unaffected in strains in which the concentration of the initiating tRNA was reduced. Alteration of the δ subunit of eIF2B, which leads to inefficient recycling, or substitution of aspartic acid for serine 51 of eIF2α had no effect on internal initiation. Production of human Pkr inhibited HCV IRES dependent initiation in yeast. The synthesis of Pkr in yeast is known to result in high levels of eIF2α phosphorylation, increased Gcn4p synthesis, and reduced ribosomal protein production. These alterations may explain the effect of Pkr synthesis on HCV IRES dependent initiation in yeast.
"IDEAL" Aging Is Associated with Lower Resting Metabolic Rate: The Baltimore Longitudinal Study of Aging

Objectives: To assess the associations among age, health status, and resting metabolic rate (RMR) in a large population of older adults. Design: Cross-sectional analysis. Setting: Community-dwelling volunteers from the Baltimore Longitudinal Study of Aging (BLSA). Participants: Persons aged 40 to 96 (mean 68.2 ± 11.0) who underwent a comprehensive physical examination, cognitive assessment, RMR testing, body composition assessment, and physical function testing during a 3-day clinic visit (N = 420). Measurements: Participants were assigned to Insight into the Determination of Exceptional Aging and Longevity (IDEAL) or non-IDEAL categories based on health status. IDEAL participants were defined according to the absence of physical and cognitive impairments, chronic conditions and comorbidities, and blood profile abnormalities. A three-stage linear regression model was used to assess the relationship between RMR and age, using IDEAL classification as a predictor and adjusting for sex and body composition. Results: Resting metabolic rate averaged 1,512.4 ± 442.9 kcal/d and was lower with older age (? = -8.55, P < .001). After adjusting for age, sex, and body composition, RMR was 109.6 kcal/d lower in IDEAL than non-IDEAL participants (P < .005). Conclusion: Individuals who are fully functional and free of major medical conditions have lower RMR than those with disease and functional impairments. These findings suggest that health status plays a role in energy use and regulation independent of age and body composition and that elevated RMR may be a global biomarker of poor health in older persons.
Computer-simulation models of scoria cone degradation

Abstract Long-term erosional modifications of the relatively simple morphology of scoria (`cinder') cones are ideally suited for study by field and computer-simulation methods. A series of temporally-distinct cones in the San Francisco and Springerville volcanic fields of Arizona provides the foundation for documenting the degradational evolution of scoria cones in a semi-arid climate. Progressive changes due to erosion are illustrated by the systematic decrease with increasing age of various morphometric parameters, including scoria cone height, cone height/width ratio (Hco/Wco), crater depth/width ratio, and slope angle. For example, Holocene–latest Pleistocene cones in the San Francisco field have a mean Hco/Wco value of 0.178±0.041, a mean maximum slope angle of 29.7±4.2°, and a mean average slope angle of 26.4±7.3°, whereas the group of Pliocene cones have values of 0.077±0.024, 20.5±5.8°, and 8.7±2.7°, respectively. Comparative morphology of scoria cones is a potentially useful dating tool for mapping volcanic fields. In order to better understand the degradational modifications of these volcanic landforms, we have developed a numerical approach to simulate the surficial processes responsible for the erosion of a typical scoria cone. The simulation algorithm can apply either a linear diffusion-equation model or a model with a nonlinear transport law. Using a finite-difference formulation, the simulation operates upon a three-dimensional scoria cone input as a matrix of elevation values. Utilizing both field and model results, the correlation between changing Hco/Wco value, cone age, and computer time step was expressed graphically to derive comprehensive values of the transport or diffusion coefficient (Df) for both volcanic fields. For the San Francisco volcanic field, Df had a calculated value of 21.4 m2/kyr for the linear model and 5.3 m/kyr for the nonlinear model, while for the Springerville volcanic field Df had a calculated value of 24.4 m2/kyr for the linear model and 6.3 m/kyr for the nonlinear model.
Co-Contraction Recruitment and Spinal Load during Isometric Pushing Tasks

Pushing and pulling tasks account for 20% of occupational low-back injury claims but few studies have investigated the neuromuscular control of the spine during these tasks. Primary torso muscle groups recruited during pushing tasks include the rectus abdominis and external obliques. However, theoretical analyses suggest that co-contraction of the paraspinal muscles is necessary to stabilize the spine during flexion exertions. A biomechanical model was implemented to estimate co-contraction and spinal load from measured surface EMG and trunk moment data recorded during trunk flexion and extension exertions. Results demonstrate that co-contraction during flexion exertions was approximately twice the value of co-contraction during extension. Co-contraction accounted for up to 47% of the total spinal load during flexion exertions and spinal load attributed to co-contraction was nearly 50% greater during flexion than during extension exertions despite similar levels of trunk moment. Results underscore the nee...
Positive relativizations of the P=? NP problem

Whether or not P is properly included in NP is currently one of the most important open problems in computer science. A deterministic polynomially time-bounded reducibility ⩽rP and its nondeterministic analogue ⩽rNP provide a positive relativization of this problem if P = NP is equivalent to P · r(B) = NP · r(B) for all oracle sets B. Initial attempts to relativize the P = ?NP problem considered reducibilities which are not known to yield positive relativizations. Baker, Gill, and Solovay [1] provided oracle sets B and B′ such that P · T(B) ≠ NP · T(B) and P · T(B′) = NP · T(B'); however, it remains open whether P ⩞ NP or, equivalently, whether the polynomially time-bounded Turing reducibility of Cook (in “Proceedings, 3rd Annual ACM Symposium on Theory of Computing, 1971,” pp. 151–158) provides a positive relativization of the problem. Book, Long, and Selman (SIAM J. Comput.13 (1984), 461–487) found a restricted form of Cook's reducibility that does provide a positive relativization. Several reducibilities between polynomially time-bounded Turing reducibility and polynomially time-bounded many-one reducibility are investigated for their ability to positively relativize the P = ?NP problem.
Is Winning Everything? The Relative Contributions of Motivational Climate and Won-Lost Percentage in Youth Sports

The purpose of this study was to examine the main and interactive effects of motivational climate and won-lost percentage upon young athletes’ evaluations of their coaches, enjoyment of their team experience, and perceived parental liking for the coach. A total of 268 male and female youth basketball players, aged 10 to 15 years, completed the Motivational Climate Scale for Youth Sports (Smith, Cumming, & Smoll, in press) and selected attitudinal scales relating to their sport enjoyment and their evaluations of their coach. Regular season won-lost percentages were calculated for each of the 50 teams. Hierarchical linear modeling was used to predict player evaluations of the coach. Attitudes toward the coach were positively associated with perceptions of a mastery-involved climate and negatively associated with perceptions of an ego-involved climate. Won-lost percentages positively predicted players’ evaluations of their coach's knowledge and teaching ability, but accounted for far less attitudinal varianc...
Periodic forcing of the CSTR: An Application of the generalized II-criterion

Nonlinearities give the opportunity to influence the time average performance of a system by periodic forcing of external parameters. In this article, this concept is applied to the following reactions occurring in a continuous stirred tank reactor: A B, A C; A ⇋ B; A B C; and A B, A + B C. It is shown, using a generalized II-criterion, that if the activation energies satisfy the constraint E1 > E2, then the yield of B is improved using high-frequency periodic perturbations in the temperature regardless of reaction order and operating conditions. Conversely, if E1 > E2, then high-frequency forcing always leads to a deterioration of the yield. There exist regions of parameter space where low-frequency forcing may lead to an improvement. Results valid for low and intermediate frequencies are developed and can be used to predict additional areas of parameter space of interest for periodic operation.
A Basic Concept in the Clinical Ethics of Managed Care: Physicians and Institutions as Economically Disciplined Moral Co-Fiduciaries of Populations of Patients

Managed care employs two business tools of managed practice that raise important ethical issues: paying physicians in ways that impose conflicts of interest on them; and regulating physicians' clinical judgment, decision making, and behavior. The literature on the clinical ethics of managed care has begun to develop rapidly in the past several years. Professional organizations of physicians have made important contributions to this literature. The statements on ethical issues in managed care of four such organizations are considered here, the American Medical Association, the American College of Physicians, the American College of Obstetricians and Gynecologists, and the American Academy of Pediatrics. Three themes common to these statements are identified and critically assessed: the primacy of meeting the medical needs of each individual patient; disclosure of conflicts of interest in how physicians are paid; and opposition to gag orders. The paper concludes with an argument for a basic concept in the clinical ethics of managed care: physicians and institutions as economically disciplined moral co-fiduciaries of populations of patients.
Charcoal—Its Manufacture and Use

Charcoal is the most ancient of manufactured plant products, dating from early prehistoric times. Today about 375,000 tons are annually produced in the United States, to he used not only as fuel but also in the metallurgical industry and as a chemical raw material Both hardwoods and softwoods are converted into it.
Robust contour tracking based on a coupling between geodesic active contours and conditional random fields

This paper presents a new general framework for contour tracking based on the synergy of two powerful segmentation tools, namely, spatial temporal conditional random fields (CRFs) and geodesic active contours (GACs). The contours of targets are modeled using a level set representation. The evolution of the level sets toward the target contours is formulated as one of the joint region-based (CRF) and boundary-based (GAC) segmentations under a unified Bayesian framework. A variational inference technique is used to solve this otherwise intractable inference problem, leading to approximate MAP solutions of both the new 3D spatial temporal CRF and the GAC model. The tracking result of the previous frame is used to initialize the curve in the current frame. Typical contour tracking problems are considered and experimental results are given to illustrate the robustness of the method against noise and its accurate performance in moving objects boundary localization.
A modified CT severity index for evaluating acute pancreatitis: Improved correlation with patient outcome

OBJECTIVE. This study was conducted to assess the correlation with patient outcome and interobserver variability of a modified CT severity index in the evaluation of patients with acute pancreatitis compared with the currently accepted CT severity index.MATERIALS AND METHODS. Of 266 consecutive patients diagnosed with acute pancreatitis during a 1-year period, 66 underwent contrast-enhanced MDCT within 1 week of the onset of symptoms. Three radiologists who were blinded to patient outcome independently scored the severity of the pancreatitis using both the currently accepted and modified CT severity indexes. The modified index included a simplified assessment of pancreatic inflammation and necrosis as well as an assessment of extrapancreatic complications. Outcome parameters included the length of hospital stay; the need for surgery or percutaneous intervention; and the occurrences of infection, organ failure, and death. For both the current and modified indexes, correlation between the severity of the pa...
Left inferior frontal gyrus is critical for response inhibition

Lesion studies in human and non-human primates have linked several different regions of prefrontal cortex (PFC) with the ability to inhibit inappropriate motor responses. However, recent functional neuroimaging studies have specifically implicated right inferior PFC in response inhibition. Right frontal dominance for inhibitory motor control has become a commonly accepted view, although support for this position has not been consistent. Particularly conspicuous is the lack of data on the importance of the homologous region in the left hemisphere. To investigate whether the left inferior frontal gyrus (IFG) is critical for response inhibition, we used neuropsychological methodology with carefully characterized brain lesions in neurological patients. Twelve individuals with damage in the left IFG and the insula were tested in a Go/NoGo response inhibition task. In alternating blocks, the difficulty of response inhibition was easy (50% NoGo trials) or hard (10% NoGo trials). Controls showed the predicted pattern of faster reaction times and more false alarm errors in the hard condition. Left IFG patients had higher error rates than controls in both conditions, but were more impaired in the hard condition, when a greater degree of inhibitory control was required. In contrast, a patient control group with orbitofrontal cortex lesions showed intact performance. Recent neuroimaging studies have focused on a highly specific association between right IFG and inhibitory control. The present results indicate that the integrity of left IFG is also critical for successful implementation of inhibitory control over motor responses. Our findings demonstrate the importance of obtaining converging evidence from multiple methodologies in cognitive neuroscience.
Health‐related quality of life and employment among renal transplant recipients

Objective: To examine the relationship between health-related quality of life (HQoL) and employment status in renal transplant recipients (RTRs). Methods: Eighty-two RTRs met inclusion criteria: 21-65 yr of age; greater than one yr post-transplant; and received calcineurin inhibitors. A cross- sectional survey was conducted using a demographics questionnaire and the following HQoL instruments: SF-12 Health Survey version 2 (Physical Component Summary (PCS-12) and Mental Component Summary (MCS- 12)) and Kidney Transplant Questionnaire (KTQ). Two multivariate lo- gistic regression analyses (SF-12 model and KTQ model) were conducted to determine whether HQoL and demographic variables were independently associated with employment status. Results: Seventy-five RTRs were included in the analysis. Compared with employed RTRs, a greater number of unemployed RTRs were non-white, had lower education levels, and had deceased donor transplants (p < 0.05). Employed RTRs had significantly higher SF-12 scores (p < 0.05). In the SF-12 logistic regression model, PCS-12 and education level were significant predictors of employment status (p < 0.05). In the KTQ model, the Fatigue subscale and education level were significant predictors of employment status (p < 0.05). Conclusions: Findings suggest higher PCS-12, higher KTQ-Fatigue, and education level are independently associated with employment status. Interventions targeted to improve HQoL, decrease fatigue, and increase education level are discussed.
Signal diversification in Oecanthus tree crickets is shaped by energetic, morphometric, and acoustic trade-offs

Physiology, physics, and ecological interactions can generate trade-offs within species, but may also shape divergence among species. We tested whether signal divergence in Oecanthus tree crickets is shaped by acoustic, energetic, and behavioral trade-offs. We found that species with faster pulse rates, produced by opening and closing wings up to twice as many times per second, did not have higher metabolic costs of calling. The relatively constant energetic cost across species is explained by trade-offs between the duration and repetition rate of acoustic signals-species with fewer stridulatory teeth closed their wings more frequently such that the number of teeth struck per second of calling and the resulting duty cycle were relatively constant across species. Further trade-offs were evident in relationships between signals and body size. Calling was relatively inexpensive for small males, permitting them to call for much of the night, but at low amplitude. Large males produced much louder calls, reaching up to four times more area, but the energetic costs increased substantially with increasing size and the time spent calling dropped to only 20% of the night. These trade-offs indicate that the trait combinations that arise in these species represent a limited subset of conceivable trait combinations.
Joint harmonic functions and their supervised connections

The cluster assumption had a significant impact on the reasoning behind semi-supervised classification methods in graph-based learning. The literature includes numerous applications where harmonic functions provided estimates that conformed to data satisfying this well-known assumption, but the relationship between this assumption and harmonic functions is not as well-understood theoretically. We investigate these matters from the perspective of supervised kernel classification and provide concrete answers to two fundamental questions. (i) Under what conditions do semi-supervised harmonic approaches satisfy this assumption? (ii) If such an assumption is satisfied then why precisely would an observation sacrifice its own supervised estimate in favor of the cluster? First, a harmonic function is guaranteed to assign labels to data in harmony with the cluster assumption if a specific condition on the boundary of the harmonic function is satisfied. Second, it is shown that any harmonic function estimate within the interior is a probability weighted average of supervised estimates, where the weight is focused on supervised kernel estimates near labeled cases. We demonstrate that the uniqueness criterion for harmonic estimators is sensitive when the graph is sparse or the size of the boundary is relatively small. This sets the stage for a third contribution, a new regularized joint harmonic function for semi-supervised learning based on a joint optimization criterion. Mathematical properties of this estimator, such as its uniqueness even when the graph is sparse or the size of the boundary is relatively small, are proven. A main selling point is its ability to operate in circumstances where the cluster assumption may not be fully satisfied on real data by compromising between the purely harmonic and purely supervised estimators. The competitive stature of the new regularized joint harmonic approach is established.
Implementation of a pharmacist-managed heart failure medication titration clinic.

Purpose The development, implementation, and initial results of a pharmacist-managed heart failure (HF) medication titration clinic are described. Summary In a quality-improvement initiative at a Veterans Affairs health care system, clinical pharmacists were incorporated into the hospital system’s interprofessional outpatient HF clinic. In addition, a separate pharmacist-managed HF medication titration clinic was established, in which pharmacists were granted an advanced scope of practice and prescribing privileges, enabling them to initiate and adjust medication dosages under specific protocols jointly established by cardiology and pharmacy staff. Pharmacists involved in the titration clinic tracked patients’ daily body weight, vital signs, and volume status using telephone-monitoring technology and via patient interviews. A retrospective chart review comparing achievement of target doses of angiotensin-converting enzyme inhibitor (ACEI), angiotensin-receptor blocker (ARB), and β-blocker therapies in a group of patients ( n = 28) whose dosage titrations were carried out by nurses or physicians prior to implementation of the pharmacist-managed HF medication titration clinic and a group of patients ( n = 27) enrolled in the medication titration clinic during its first six months of operation indicated that target ACEI and ARB doses were achieved in a significantly higher percentage of pharmacist-managed titration clinic enrollees (52.9% versus 31%, p = 0.007). Patients enrolled in the pharmacist-managed HF medication titration clinic also had a significantly higher rate of attainment of optimal β-blocker doses (49% versus 24.7%, p = 0.012). Conclusion Implementation of a pharmacist-managed HF medication titration clinic increased the percentage of patients achieving optimal ACEI, ARB, and β-blocker dosages.
THE EFFECT OF INTERTIDAL ENVIRONMENT ON THE COMPOSITION OF CALCAREOUS SKELETAL MATERIAL1

Oysters and barnacles were collected in the intertidal zone from four pilings within the estuary system near Sapelo Island, Georgia. The calcareous skeletal material was analyzed for Sr, Fe, Mg, Na, and Mn. Distinct and regular differences in skeletal composition were found. Sr and Mn exhibit some particularly close linear relationships between composition and piling level. Mg is the only element for which no linear relationship was observed.
THE DYNAMICS OF RETICULOENDOTHELIAL BLOCKADE.

The dynamics of "reticuloendothelial blockade" were studied in living rabbits and isolated, perfused rabbit livers utilizing gelatin as a blockading agent and Au198 stabilized in gelatin as a tracer. Employing the above experimental model, the following observations were made. (a) RES blockade was specific and dependent on the surface properties of the particle under study. (b) RES blockade was not caused by saturation of hepatic removal mechanisms. (c) RES blockade was not caused by depletion of demonstrable serum opsonins. (d) RES blockade appeared to correlate with high circulating levels of the blockading agent, per se. Thus, under the conditions employed, the term "reticuloendothelial blockade" was a misnomer. Although specificity of liver macrophage-particle interaction was evident and deserves further study, the data suggest that blockade as usually studied is a laboratory phenomenon induced by the continuing circulation of the blockading agent.
Statistical expression deconvolution from mixed tissue samples

Motivation: Global expression patterns within cells are used for purposes ranging from the identification of disease biomarkers to basic understanding of cellular processes. Unfortunately, tissue samples used in cancer studies are usually composed of multiple cell types and the non-cancerous portions can significantly affect expression profiles. This severely limits the conclusions that can be made about the specificity of gene expression in the cell-type of interest. However, statistical analysis can be used to identify differentially expressed genes that are related to the biological question being studied. Results: We propose a statistical approach to expression deconvolution from mixed tissue samples in which the proportion of each component cell type is unknown. Our method estimates the proportion of each component in a mixed tissue sample; this estimate can be used to provide estimates of gene expression from each component. We demonstrate our technique on xenograft samples from breast cancer research and publicly available experimental datasets found in the National Center for Biotechnology Information Gene Expression Omnibus repository. Availability: R code ( http://www.r-project.org/) for estimating sample proportions is freely available to non-commercial users and available at http://www.med.miami.edu/medicine/x2691.xml Contact: jclarke@med.miami.edu
CALCI Websheets - calculation enabled web documents

The extensive dynamic capabilities of the browser allow for platforms of infinite extensibility and omni-functional power to be delivered via the internet. This paper considers the possibilities of converting web pages into an intelligent immersive omni-functional platform with special focus on calculations. Such standards-compliant documents with omni-functionalities (enhanced by calculations, but including advanced graphics, picture manipulation, composition, presentation, etc.) can be intermingled with semantic web structures to create powerful models for the next generation of the Internet. The paper builds on the features that are extended by such representations, and imply potential solutions that can be developed from such strategies. The paper documents the possibility of converting every webpage into a full-fledged calculation platform (named Websheets) that demonstrate more power than the most advanced spreadsheet tools available today.
Association of common variations on chromosome 4q25 and left atrial volume in patients with atrial fibrillation.

Aims: Recent studies have shown that several genetic variants near the PITX2 locus on chromosome 4q25 are associated with atrial fibrillation (AF). However, the mechanism that mediates this association remains unclear. Basic murine studies suggest that reduced PITX2 expression is associated with left atrial dilatation. We sought to examine the association between single nucleotide polymorphisms (SNPs) near PITX2 and left atrial size in patients with AF. Methods: We prospectively enrolled 96 consecutive patients (mean age 60 ± 10 years, 72% male) with drug-resistant AF (57% paroxysmal, 38% persistent, and 5% long-standing persistent) who underwent catheter ablation. Following DNA extraction from blood obtained pre-operatively, SNPs rs10033464 and rs2200733 were genotyped using the Sequenom MassARRAY. Left atrial volume (LAV) was determined using three-dimensional imaging (CT or MRI prior to first ablation) and by investigators blinded to genotype results. Results: The minor allele frequencies at SNPs rs10033464 and rs2200733 were 0.14 and 0.25, respectively. Using multivariable linear regression, homozygosity for the minor allele at rs10033464 (recessive model) was independently associated with larger LAV (P = 0.002) after adjustment for age, gender, BMI, height, type, and duration of AF, left ventricular ejection fraction, history of hypertension, valve disease, and antiarrhythmic drug use. The strength of the association was reconfirmed in a bootstrap study with 1000 resamplings. In contrast, no association was found between rs2200733 variant alleles and LAV. Conclusion: SNP rs10033464 near the PITX2 locus on 4q25 is associated with LAV. Left atrial dilatation may mediate the association of common variants at 4q25 with AF.
Coupled oscillations in a platform with four springy legs and local feedback

Based on the modeling of animal central pattern generators by networks of coupled oscillators, approaches for four-legged robot control are considered. As a first step, the effect of a simple local feedback at each of four springy legs on a platform is examined. Using classical averaging, it is shown that stable oscillations occur which correspond to four-legged animal gaits. In addition, numerical experiments demonstrate the feasibility of further augmenting the local controllers with a coupled oscillator controller to perform gait transitions.
Lyophilization and Reconstitution of Reverse-Osmosis Concentrated Natural Organic Matter from a Drinking Water Source

AbstractDrinking water treatment research can be complicated by difficulties in shipping large water quantities and changing natural organic matter (NOM) characteristics over time. To overcome these issues, it is advantageous to have a reliable method for concentrating NOM with minimal loss and maximum shelf-life. NOM concentration and preservation by lyophilization (freeze-drying) has been practiced for many years; however, little information for lyophilizing and reconstituting NOM exists in the literature. The purpose of this research was to both evaluate and improve the lyophilization process of a concentrated NOM solution and to determine the appropriate conditions (pH, mixing time, and concentration factor) under which to reconstitute lyophilized NOM for maximum total organic carbon (TOC) and ultraviolet absorbance at 254-nm (UV254 ) recovery. To achieve this, a new lyophilization method was developed, in which NOM concentrate is supercooled below its freezing point and heat transfer is carefully reg...
Collaborative technologies in knowledge telework: an exploratory study

Abstract. Knowledge workers in distributed work environments require substantial communication with colleagues and supervisors to perform their work activities, and collaborative technologies, like groupware, continue to improve the potential for such communication. This study investigates how an improvement in collaborative technology among a group of knowledge teleworkers impacts their communication patterns. The study focuses on one communication-based work process: knowledge sharing. The research involves a 6-month exploratory longitudinal case study of a group of teleworkers where a new groupware technology was implemented. The results indicate that while there are fewer instances of communication among group members after the technology is implemented, communication becomes more centralized around the district manager. These results suggest that increased collaborative technologies result in an adjustment between explicit and tacit knowledge sharing, as the availability of a centralized and updateable database reduces workgroup communications. However, consistent with structuration theory, telework group members do use communication technologies to address their most apparent needs and concerns. Other potential explanations and implications of these findings are discussed.
P5B-6 In Vitro Pressure Estimation Obtained from Subharmonic Contrast Microbubble Signals

The long term goal of this project is to monitor and quantifyintra-cardiac pressures via contrast-enhanced subharmonic imaging. Our group has proposed the concept of subharmonic aided pressure estimation (SHAPE) utilizing microbubble-based contrast agent signals for the noninvasive estimation of hydrostatic blood pressures in heart cavities and major blood vessels. An experimental system for in vitro SHAPE was constructed based on two single-element transducers assembled confocally at a 60deg angle to each other. Changes in the first, second, and subharmonic amplitudes of the contrast agents Sonazoid, Optison, Definity, PRC-1 and Levovist were measured in vitro over a pressure range from 0 to 186 mmHg using a sealed 2.25 L water tank that can sustain pressure changes in excess of 200 mmHg. Over the pressure range studied the first and second harmonic amplitudes reduced only approximately 2.4 dB and 1.8 dB in vitro. Over the same pressure range, the subharmonic amplitudes of the agents decreased between 9.6 and 13 dB. Excellent linear regressions (r > 0.98; p > 0.001) were achieved between the subharmonic amplitude and hydrostatic pressure for all five agents tested. In conclusion, the subharmonic microbubble signal component is a good indicator of the hydrostatic pressure variation in vitro. SHAPE offers the possibility of allowing pressure gradients in the heart to be obtained noninvasively. Future studies will include in vivo pressure measurements.
Radium Sampling Methods and Residence Times in St. Andrew Bay, Florida

Activity ratios (AR) of radium isotopes have been used with success to constrain estimates of water ages and to approximate residence times in coastal waters. We compared two common radium sampling methods (grab sampling and stationary moorings) to estimate water ages and the residence time of St. Andrew Bay waters in northwest Florida, USA. Both sampling methods utilize manganese dioxide fibers (“Mn fibers”) to adsorb dissolved radium from the water column. Grab samples capture radium activities at a discrete time while moorings integrate radium activities over longer deployments. The two methods yielded similar results in this study and thus both approaches are useful for water age comparisons and residence time approximations. However, since radium often varies as a function of tidal stage, deploying moorings over a complete tidal cycle is the preferred approach. An estimated residence time for North Bay and West Bay of 8–11 days was approximated using ARs for both ex224Ra/223Ra and ex224Ra/228Ra. Some complications were introduced as St. Andrew Bay is a tidally dominated, rather than a river-dominated bay system where this method has previously been applied. The largest freshwater source to this bay system is from a man-made reservoir, with an average freshwater flow of only 20 m3 s−1. The activity concentrations and ARs measured by both sampling methods suggest that while the reservoir is the prominent radium source, it is not the only radium source. Nonetheless, a tidal mixing model applied to the western half of the system yielded an approximate flushing time of 10–12 days, similar to that derived from our radium-based water age approach.
Hydrolyzable ATP and PIP2 Modulate the Small-conductance K+ Channel in Apical Membranes of Rat Cortical-Collecting Duct (CCD)

The small-conductance K+ channel (SK) in the apical membrane of the cortical-collecting duct (CCD) is regulated by adenosine triphosphate (ATP) and phosphorylation-dephosphorylation processes. When expressed in Xenopus oocytes, ROMK, a cloned K+ channel similar to the native SK channel, can be stimulated by phosphatidylinositol bisphosphate (PIP2), which is produced by phosphoinositide kinases from phosphatidylinositol. However, the effects of PIP2 on SK channel activity are not known. In the present study, we investigated the mechanism by which hydrolyzable ATP prevented run-down of SK channel activity in excised apical patches of principal cells from rat CCD. Channel run-down was significantly delayed by pretreatment with hydrolyzable Mg-ATP, but ATPγS and AMP-PNP had no effect. Addition of alkaline phosphatase also resulted in loss of channel activity. After run-down, SK channel activity rapidly increased upon addition of PIP2. Exposure of inside-out patches to phosphoinositide kinase inhibitors (LY294002, quercetin or wortmannin) decreased channel activity by 74% in the presence of Mg-ATP. PIP2 added to excised patches reactivated SK channels in the presence of these phosphoinositide kinase inhibitors. The protein kinase A inhibitor, PKI, reduced channel activity by 36% in the presence of Mg-ATP. PIP2 was also shown to modulate the inhibitory effects of extracellular and cytosolic ATP. We conclude that both ATP-dependent formation of PIP2 through membrane-bound phosphoinositide kinases and phosphorylation of SK by PKA play important roles in modulating SK channel activity.
INFLUENCE OF GENETIC FACTORS ON THE MAGNITUDE AND THE HETEROGENEITY OF THE IMMUNE RESPONSE IN THE RABBIT

Selective breeding of rabbits immunized with Group C and Group A streptococcal vaccines was employed to reveal genetic influences on the magnitude and on the restriction in heterogeneity of the immune response to the group-specific carbohydrates. After two generations of selective breeding, complete segregation was achieved between a high-response population (>18 mg precipitins/ml serum, average 33 mg/ml) and a low-response population (<13 mg precipitins/ml serum, average 7.5 mg/ml) to Group C carbohydrate. This suggests that a limited number of genes controls the magnitude of the immune response to this antigen. Selective breeding of rabbits which were representative of heterogeneous, restricted, and monoclonal responses revealed that the degree of antibody heterogeneity in the parental rabbits is reflected in the offspring. More than 95% of the offspring derived from rabbits which had a heterogeneous immune response developed heterogeneous antibodies. 33% of the offspring derived from rabbits which had restricted and monoclonal immune responses developed monoclonal antibodies. This suggests that the degree of heterogeneity of the antibody response to the streptococcal carbohydrates is under genetic control. The degree of heterogeneity and the magnitude of the immune response appear to be independent variables.
Characteristic polynomials of finitely generated modules over Weyl algebras

The role of Hilbert polynomials in commutative algebra and algebraic geometry is well known. In [2] Bernstein introduced an analog of the Hilbert polynomial for a finitely generated filtered module over a Weyl algebra and extended the theory of multiplicity to the class of such modules. The results of this study have found interesting analytical applications (many of them are considered in Bjork's book [4]). In particular, they allowed Bernstein [3] to prove the Gelfand's conjecture on meromorphic extensions of functions Tf(X) — J P(x)f(x)dx of one complex variable A defined in the half-space Re(X) > 0 for any polynomial in n real variables P(x) = P(x\,... ,xn) and for any function f{x) = f(Xl, ...,xn)€ C g ° ( R n ) . In what follows we prove the existence, determine invariants and outline methods of computation of dimension polynomials in two variables associated with the natural bifiltration of a finitely generated module over a Weyl algebra An(K). We show that such polynomials not only characterise the Bernstein class of left An (K) -modules, but also carry, in general, more invariants than the dimension polynomials introduced by Bernstein.
Metropolitan Structure and Criminal Violence

This article re-examines the conclusions of an earlier paper (Blau and Blau. 1982); i.e., that racial inequality in metropolitan places increases criminal violence and is accountable for various fa...
Cold rolled ABS. Part 1: The effect of rubber particle size on the tensile properties of ABS before and after cold rolling†

The effect of rubber particle size on the tensile properties of rolled and unrolled acrylonitrile-butadiene-styrene has been studied by considering model systems consisting of mixtures of a small particle (0.1 micron diam) rubber, S, and a large particle (0.56 micron diam) rubber, L, in an SAN matrix. Before rolling, tensile toughness is characterized by crazing. While both rubber induce matrix crazing, ABS systems containing only the S rubber exhibits early failure due to crack formation, before crazing is propagated very far along the tensile axis. The inefficiency of the small particle rubber is interpreted in terms of high composite yield stress and insufficient distance between particles to allow craze branching. The efficiency of the small particle rubber is improved via the addition of a small amount of large particle, L, rubber to the composite or by a slight degree of cold rolling, both of which enhance craze propagation in the tensile direction. With further rolling, the tensile deformation mode changes from one of localized crazing, which is propagated, to one of uniform deformation, which occurs without crazing.
Identification of Supplementary Metrics to Sustain Fleet Readiness from a Maintenance Perspective

A wide variety of programs and schemes are in place (and many programs are in continuous development by organizations such as the Office of Naval Research) that address the sustainability of the Navy's Fleet. Newly developed technologies are allowing for the continued design and development of much more complex ships with a host of innovative concepts and requirements. The cost of construction of these next-generation ships, budgetary restraints, and other factors have also made it so necessary to maintain, adapt, and extend the life of the legacy fleet to meet operational requirements and maintain our maritime dominance. As we extend and adapt technology to become implemented across the wide variety of vessel platforms in existence in the legacy fleet, manning reductions are being implemented across the various ship-type classes. As more and more maintenance is being shifted from the sailors on the ships to various off-ship organizations, this brings into question the level of training necessary for ship's personnel in the maintenance area that is required when manning the ship from a tactical or operational perspective. Decision tools need to be developed for senior Navy management for use in evaluating and determining the optimal balance in manning ships from not only the operational perspective but also from the maintainability/survivability perspective. It is believed evaluation of the requirements, benchmarking, and the development of assessment metrics for determining the requirements of the Fleet for capable maintainers are of vital importance and will have far-reaching impact on the Sea Warrior, Sea Trial, and Sea Enterprise programs in support of the "Sea Power 21" strategic concept of the Navy. This paper explores the necessity of benchmarking current ship's force capabilities, establishing manning requirement metrics, and evaluation of current maintenance policies.
Raman spectra of graphite as indicators of degree of metamorphism

This study demonstrates the usefulness of Raman microspectroscopy an evaluation of the crystallinity of graphite in natural samples. The sensitivity obtained is at least as good as that for X-ray diffractometry. Laser Raman microprobe analyses of graphite separates, mostly from suites of regionally metamorphosed carbon-bearing pelites (Grew 1974), show that l) the spectra oferaphite accurately reflect the degree of crystallinity in terms of the (001) inplane crystallite size, 2) the same spectral features and changes with crystallinity occur in the spectra of natural graphite as in those of synthetic samples, 3) the Raman spectrum is a sensitive monitor of changes in graphite crystallinity, reflecting conditions from greenschist- to granulitefacies metamorphism, 4) significant changes in the Raman spectral profile coincide with transitions in the metapelites that delineate the chlorite, biotite + garnet, staurolite -r. kyanite + andalusite, and sillimanite zones, and 5) the graphite stmcture apparently records only the peak metamorphic temperatures and does not recrystallize under retrograde conditions.
Teaching excellence in public health: a call to action.

'"Publish or perish' is the mantra of faculty members at most major universities nationwide. While research and its resulting publications are vital to [universities], teaching excellence must be, too. But unfortunately, that is not always the case?especially in professional schools that rely on 'soft' money, salary funding that individual researchers raise for themselves through grants."1 ?David Kleinbaum, first recipient of the Association of Schools of Public Health (ASPH)/ Pfizer Award for Teaching Excellence
Observations of barroom drinking; methodology and preliminary results.

Data from a field study of barroom behavior indicate that most people do not stay very long or consume many drinks in a bar, that the number of sips per drink is a reliable measure of drinking rate...
Taking the Measure of National Bandwidths: Evolving Patterns of the International Digital Divide for 1986-2013

The article measures different aspects of the evolution of the international digital divide between 1986 and 2013. The traditional approach of measuring digital development in terms of telecom subscriptions is increasingly becoming obsolete, especially as mobile phone penetration reaches population saturation levels. It shows that the bandwidth divide continuous to be dynamic and is very persistent, as it can closely be linked to the international income divide. Novel findings reveal that only 3 countries host 50 % of the globally installed bandwidth potential (10 countries 75 %), that the digital divide between high-and low income countries in terms of kbps per capita has increased between 2001 and 2008, only decreasing below historic levels very recently during 2012-2013, and that the contribution of mobile to global bandwidth is continuously fluctuating with incessant technological innovation, reaching almost 40 % in both 2001 and 2013, while falling to 16 % in 2007.