cssi/SciSciGPT-SciSciNet huggingface dataset:
Ankle-brachial index, toe-brachial index, and cardiovascular mortality in persons with and without diabetes mellitus.

Background The prognostic utility of the ankle-brachial index (ABI) may be hampered in persons with diabetes due to peripheral arterial stiffening in the ankles. Stiffening of toe arteries occurs infrequently in diabetes. We aimed to determine the nature of the relationship of the toe-brachial index (TBI) and ABI with cardiovascular disease (CVD) mortality and to determine whether the associations are modified in individuals with diabetes. Methods Individuals with clinically suspected atherosclerotic peripheral arterial disease who underwent ABI and TBI measurements in a vascular laboratory were monitored longitudinally for CVD mortality. Results Among 469 participants (89% men), the mean age was 68 ± 9 years, and 36% had diabetes. The mean ABI was 0.83 ± 0.28 and the mean TBI was 0.60 ± 0.24. During median 7.0 years of follow-up, there were 158 CVD deaths. The association of the ABI categories with CVD deaths differed in diabetic vs nondiabetic participants ( P = .002 for interaction). In contrast, the association of the TBI categories with CVD deaths was similar, irrespective of diabetes status ( P = .17 for interaction). Among diabetic patients, a U-shaped relationship was observed between ABI categories and CVD death: those with low ( 1.30) ABIs were both at higher risk than those with normal ABIs (range, 0.90-1.30). In nondiabetic patients, association of ABI categories with CVD death was linear, such that those with an ABI >1.30 were at the lowest risk, whereas those with an ABI Conclusions Among diabetic individuals with clinically suspected peripheral arterial disease, those with low and high ABIs are both at higher risk of CVD death. In contrast, a linear relationship was observed between TBI categories and CVD death irrespective of diabetes status. These findings suggest that stiffened ankle arteries may limit the predictive value of the ABI in individuals with diabetes, a limitation that may be overcome by measurement of the TBI.
Environmental signals and cell fate specification in premigratory neural crest.

Neural crest cells are multipotent progenitors, capable of producing diverse cell types upon differentiation. Recent studies have identified significant heterogeneity in both the fates produced and genes expressed by different premigratory crest cells. While these cells may be specified toward particular fates prior to migration, transplant studies show that some may still be capable of respecification at this time. Here we summarize evidence that extracellular signals in the local environment may act to specify premigratory crest and thus generate diversity in the population. Three main classes of signals–Wnts, BMP2/BMP4 and TGFβ1,2,3–have been shown to directly influence the production of particular neural crest cell fates, and all are expressed near the premigratory crest. This system may therefore provide a good model for integration of multiple signaling pathways during embryonic cell fate specification. BioEssays 22:708–716, 2000. © 2000 John Wiley & Sons, Inc.
Prediction of Mastitis Using Milk Somatic Cell Count, N-Acetyl-β-D-Glucosaminidase, and Lactose

The objectives of this work were 1) to examine the responsiveness of SCC, lactose concentration, and NAGase activity in milk to changes in bacteriological status and 2) to develop models for predicting bacteriological status of mammary glands. Data included 550 cows in 10 commercial herds. Natural logarithm NAGase and log cell count were most responsive to changes in bacterial status. The log NAGase was relatively more effective in identifying major from minor pathogen infections, whereas log SCC was better able to differentiate between infected and uninfected classes. Non-transformed NAGase, SCC, and lactose were considerably less responsive to infection status. Logistic regression of bacterial status on herd, lactation number, milk, log SCC, log NAGase, and stage of lactation was performed. The least significant variables were removed in a stepwise process. Final predictors of infection status were herd, log SCC, and log NAGase. The role of log SCC was to discriminate infection from no infection, whereas log NAGase discriminated major from minor pathogens. The log NAGase, alone or in combination with log SCC, added substantially to the detection power of the model. Chi-square goodness of fit tests found no significant differences between observed and predicted infection probabilities. Substitution of herd averages for log SCC and log NAGase for the herd variables resulted in significant differences between predicted and observed herd infection probabilities.
Field data analysis of occupant injury during rollover crashes

Some researchers have found a general correlation between vehicle roof deformation and occupant injury by using field accident data. However, this correlation does not represent causality, because both roof deformation and occupant injury are related to impact severity. To examine the relationship between roof deformation and injuries, this study compared the injury odds with and without roof deformation under different levels of impact severities using single-vehicle rollover crash data from the NASS-CDS database. The results demonstrated that the number of potential roof-to-ground impacts was an indicator of rollover severity, there was no clear correlation between injury odds and roof deformation under similar impact severity, and there was no clear correlation between ejection odds and roof deformation for unbelted occupants under similar impact severity. The results also showed that the injury odds for females were double those for males, and there was a strong correlation between age and injury odds.
A resonance mechanism in plane Couette flow

The temporal evolution of small three-dimensional disturbances on viscous flows between parallel walls is studied. The initial-value problem is formally solved by using Fourier–Laplace transform techniques. The streamwise velocity component is obtained as the solution of a forced problem. As a consequence of the three-dimensionality, a resonant response is possible, leading to algebraic growth for small times. It occurs when the eigenvalues of the Orr–Sommerfeld equation coincide with the eigenvalues of the homogeneous operator for the streamwise velocity component. The resonance has been investigated numerically for plane Couette flow. The phase speed of the resonant waves equals the average mean velocity. The wavenumber combination that leads to the largest amplitude corresponds to structures highly elongated in the streamwise direction. The maximum amplitude, and the time to reach this maximum, scale with the Reynolds number. The aspect ratio of the most rapidly growing wave increases with the Reynolds number, with its spanwise wavelength approaching a constant value of about 3 channel heights.
Synthesis of sedoheptulose from non-dialyzable, endogenous substrates in mammalian tissue extracts

Sedoheptulose was observed to be formed at the rate of 12-120 nmol/g tissue/h in dialyzed rat and bovine tissue homogenates. The compound was identified by its gas-chromatographic retention time and by its mass spectrum. A standard of [14C]-sedoheptulose was prepared from D-[14C]fructose 6-phosphate and D-erythrose 4-phosphate for use in radioactive gas-chromatographic analysis in studies of possible precursors of the sedoheptulose. The reaction was stimulated by NAD+. Evidence is presented to show that non-dialyzable sedoheptulose 7-phosphate may be the endogenous precursor. These results show that care must be exercised when using crude enzyme preparations and extremely sensitive analytical methods so that chromatographically unresolved products formed from non-dialyzable, endogenous substrates of low molecular weight do not introduce significant error in the analysis of the expected product.
The effects of amphetamine isomers on rotarod performance.

The amphetamine isomers impair the rotarod performance of rats in a dose-related manner, with (+)-amphetamine approximately four-times as potent as its (-)-isomer. At a rotation speed of 4 rpm, 60 min after i.p. administration, the TD50 values (mg/kg) were: (+)-amphetamine, 24 (21.9–26.4) and (-)-amphetamine, 96 (76.3–118.4), with the curves not deviating from parallelism. Coadministration of the peripheral cholinesterase inhibitor neostigmine salicylate (0.005 mg/kg) attenuated (+)-amphetamine neurotoxicity [30 (26.4–34.1)]. These results, in conjunction with previously reported effects of the drug on isolated nerve-muscle preparations, suggest that the muscle weakness produced by high doses of amphetamine may result from inhibition of transmission at the neuromuscular junction.
A Spatial Analysis of Tourism, Entrepreneurship and the Entrepreneurial Ecosystem in North Carolina, USA

AbstractIn light of the projected long-term national economic trends, the vulnerability of rural regions, and the difficulty of small businesses to stay solvent, it is imperative to understand the critical elements within a small business' operating environment or “ecosystem” that support or thwart entrepreneurial activity. Using the 100 counties of North Carolina as a case study, the purpose of this research project was to determine which entrepreneurial ecosystem elements (E3) have the most influence on tourism and entrepreneurship, to identify spatial patterns in this relationship, as well as the extent to which entrepreneurial and tourist activity overlap regionally. Using national secondary data sources, the authors identified that the interaction of entrepreneurship with the proportion of those employed in the creative class is strongly associated with the growth in the number of new establishments and employment, particularly in those rural counties endowed with attractive outdoor amenities.
The preparation and catalytic applications of supported zirconocene and hafnocene complexes

Abstract Polymer-attached Cp2ZrCl2, Cp2HfCl2, CpZrCl3, CpHfCl3, Cp2ZrCl and Cp3HfCl have been prepared. The polymer-attached Cp2ZrCl2, on reduction with BuLi, produced an active catalyst whose efficiency for olefin hydrogenation is about eight times as great as that of the corresponding homogeneous species under the same conditions. The reduction products of supported zirconocene and hafnocene complexes are active hydrogenation catalysts for diphenylacetylene which was hydrogenated to 1,2-diphenylethane through intermediate stilbene. The similar reduction products have also been employed in catalytic isomerization of allylbenzene, cis-stilbene and 1,5-cyclooctadiene. Allylbenzene was converted into a mixture of trans- and cis-propenylbenzene, cis-stilbene was isomerized to trans-stilbene, and 1,5-cyclooctadiene was isomerized to 1,3-cyclooctadiene through the 1,4-cyclooctadiene intermediate. Polymer-attached Cp2ZrCl2, CpZrCl3, Cp2HfCl2, and CpHfCl3 can be used directly, without going through the reduction process, for the low yield epoxidation of cyclohexene. Polymer-attached Cp2ZrCl2 was used in hydrozirconation and carbon monoxide reduction studies.
Basic computational problems in the finite element analysis of shells

Abstract The purpose of this paper is to examine the two fundamental questions in the finite element analysis of shells; namely, the rates of convergence resulting from different interpolation schemes for the inplane and normal displacements, and the dependence of the condition number of the resulting algebraic system on the various parameters both of the shell and of the discretization.
Cognitive hurdles in the use of decision support systems to enhance problem understanding

Computer-assisted decision support systems have been widely promoted as a means of enhancing problem understanding in crisis and noncrisis decision making. Clinical observation of actual applications of a particular category of software for interactive decisions (CONAN, DECISIONMAKER) have identified cognitive hurdles in the use of such systems. These hurdles not only pose a challenge to the development of such normative interventions in the decision process, but also an opportunity for furthering the shift to a new psychologically informed paradigm for decision making.
Implicit multigrid techniques for compressible flows

Recent advances in the development of the diagonalized alternating direction implicit multigrid method for compressible aerodynamic problems are reviewed. These include the extension of the method originally developed for the Euler equations to include viscous effects, the computation of turbulent flows and the implementation on parallel computers of the scheme on multiblock rids.
Effects of septal lesions on the lordotic behavior of weanling male and female rats.

Abstract Twenty-four-day-old weanling male and female rats were either lesioned in the septal area, gonadectomized, lesioned and gonadectomized, or not treated. Tests for lordotic behavior were carried out at 27 and 28 days of age after priming with estradiol alone and with estradiol plus progesterone. A second set of tests for lordotic behavior was carried out at 47 and 48 days of age. In the interim period, some of the animals were given chronic estrogen treatment. In tests given at 27 days of age, septal lesions facilitated lordotic responding after estrogen priming; no differences were observed between male and female animals. At 47 and 48 days of age, however, unless male rats had been exposed to chronic estrogens following septal lesioning, no facilitation of estrogen-induced lordotic behavior occurred. In addition, it was found that female rats gonadectomized at 24 days of age and given no exposure to estrogens between the tests at 27 and 28 days and those at 47 and 48 days of age showed reduced sensitivity to estrogens, as compared to normal or estrogen-treated females, whether lesioned or not.
Protection against hydrogen peroxide-induced cell death in cultured human retinal pigment epithelial cells by 17β-estradiol: A differential gene expression profile

It has been demonstrated that estrogen receptors are present in the retinal pigment epithelium (RPE)-choroids complex regardless of sex. This suggests that estrogen could play a functional role in the outer retina, especially the RPE. To gain further insights on the molecular mechanisms differentially activated by 17beta-estradiol (betaE2) in RPE cells, we investigated gene expression changes in response to betaE2 in cultured RPE cells using cDNA microarray technology. A total of 47 genes among 21,329 human genes are significantly altered in response to betaE2 treatment in RPE cells. Among these 47 altered genes, 34 are up-regulated and 13 are down-regulated by betaE2. The products of 34 genes have a known or suspected function. These functions belong to various categories, including caspases; extracellular matrix proteins; metabolism pathway components; GTP/GDP exchangers and G-protein GTPase activity modulators; transcription activators and repressors. Six genes which may contribute to the unique functions of the RPE cells have been validated by both quantitative real-time reverse transcription (RT)-PCR and semi-quantitative RT-PCR. In addition, we also demonstrated that betaE2 quenches H2O2-induced up-regulation of apoptosis-related protein, and protects RPE cell degeneration. These results indicate that estrogen regulates functions of RPE cells and is involved in the maintaining and survival of RPE cells during oxidative stress, and its deficiency during menopause period may be a factor contributing to the development of age-related macular degeneration in elderly women.
Possible structural role of the disaccharide unit in Fe-bleomycin before and after oxygen activation

Our previous investigation of the solution structure of Fe(II)-bleomycin pointed toward the carbamoyl group in the mannose moiety or a water molecule as possible alternative axial ligands to the metal center in this metallo-bleomycin. The possibility of a solvent molecule occupying the apical position trans to the primary amine has not been ruled out yet. In order to explore this possibility even further, the coordination chemistry of azide-bound Fe(II)-bleomycin was investigated with the use of NMR applied to paramagnetic molecules. Fe(II)- and apo-bleomycin were also re-visited. Comparison of the NMR results for both Fe(II)-bound molecules obtained in the present study strongly suggests that the carbamoyl oxygen is ligated to Fe(II), and it is released from coordination upon azide binding. This event is suggested based on the diminished paramagnetic character exhibited by the carbohydrate moiety in Fe(II)-azide-bleomycin when compared with its parent metal complex. A possible structural role for the glucopyranose fragment, which changes throughout the process that starts with metallo-bleomycin formation and ends with DNA binding, is discussed. The study of the coordination of azide by Fe(II)-bleomycin through NMR has not been reported previously. Unlike magnetic CD data, NMR offers a residue-by-residue account of the possible structural changes that take place in Fe(II)-bleomycin after azide binding.
Cardiovascular risk factors after liver transplantation

1. Yearly screening of liver recipients with serum cholesterol, triglycerides, and lipoproteins, and assessment for risk factors for atherosclerotic cardiovascular disease, is an important component of comprehensive post transplant care. 2. Revised guidelines and target levels of LDL-cholesterol levels specific for moderate and high cardiovascular risk patients have been recently revised. 3. Transplant physicians should be aware of advances in the management of post transplant arterial hypertension, diabetes mellitus, obesity, and nicotine dependence.
Congenital Heart Surgery Nomenclature and Database Project: transposition of the great arteries

The extant nomenclature for transposition of the great arteries (TGA) is reviewed for the purposes of establishing a unified reporting system. The subject was debated and reviewed by members of the STS-Congenital Heart Surgery Database Committee and representatives from the European Association for Cardiothoracic Surgery. All efforts were made to include relevant nomenclature categories including synonyms where appropriate. The general categories of TGA are: TGA with intact ventricular septum, TGA with ventricular septal defect (VSD) and TGA with VSD and left ventricular outflow tract obstruction (LVOTO). A comprehensive database set is presented which is based on a hierarchical scheme. Data are entered at various levels of complexity and detail that can be determined by the clinician. A detailed hierarchical system is described herein for classification of the coronary artery anatomy associated with TGA. These data can lay the foundation for comprehensive risk stratification analyses. A minimum database set is also presented which will allow for data sharing and would lend itself to basic interpretation of trends.
Critical reexamination of Pierce's space-charge factor (QC) in the conventional TWT theory

We have used several different methods to calculate the dispersion relation of the space charge waves on a sheet beam inside a slow wave structure. Pierce's parameters C and QC in his traveling wave tube (TYT) theory are evaluated. Contrary to the conventional theory, we find no unique identification of the space charge fields and the circuit fields in beam-structure interaction. The interdependence between these fields is addressed.
Disposal of NORM Waste in Salt Caverns

Some types of oil and gas production and processing wastes contain naturally occurring radioactive materials (NORM). If NORM is present at concentrations above regulatory levels in oil field waste, the waste requires special disposal practices. The existing disposal options for wastes containing NORM are limited and costly. This paper evaluates the legality, technical feasibility, economics, and human health risk of disposing of NORM-contaminated oil field wastes in salt caverns. Cavern disposal of NORM waste is technically feasible and poses a very low human health risk. From a legal perspective, there are no fatal flaws that would prevent a state regulatory agency from approving cavern disposal of NORM. On the basis of the costs charged by caverns currently used for disposal of nonhazardous oil field waste (NOW), NORM waste disposal caverns could be cost competitive with existing NORM waste disposal methods when regulatory agencies approve the practice.
Stability and nonsingular stable precompensation: An algebraic approach

The module theoretic framework in linear time invariant system theory is extended to include stability considerations as well. The resulting setup is then applied to an investigation of nonsingular, causal, and stable precompensation. The main issues are resolved through the introduction of two sets of integer invariants-thestability indices and thepole indices. The stability indices characterize the dynamical properties of all the stable systems that can be obtained from a specified system through the application of nonsingular, causal, and stable precompensation. The pole indices characterize the dynamical properties of all the nonsingular, causal, and stable precompensators that stabilize a specified system.
Longing to be Langston

This article is an autoethnodrama, which originally began as a workshop piece coming to fruition as an enacted staged reading at the University of Illinois during Fall 2011. As an ethnodrama, the a...
Does prohibiting child labor increase secondary school enrolment? Insights from a new global dataset

Abstract Objective This article examines the association between minimum age of employment and secondary school enrolment. Methods We reviewed child labor laws for 185 states in 2008 and 2012. We assessed how many countries had a minimum age of employment of 15 or over and tested the association between these laws and secondary enrolment rates, after controlling for per-capita GDP, level of urbanization, and compulsory lower secondary education. Results A minimum age of employment of 15 or higher was significantly associated with increased secondary enrolment for girls, boys, and overall. Conclusions Combining a legislated minimum age of employment of 15 or higher with compulsory education may strengthen children's opportunity to achieve a secondary education.
Trapping a Single Vortex and Reducing Quasiparticles in a Superconducting Resonator

Vortices trapped in thin-film superconducting microwave resonators can have a significant influence on the resonator performance. Using a variable-linewidth geometry for a weakly coupled resonator, we are able to observe the effects of a single vortex trapped in the resonator through field cooling. For resonant modes where the vortex is near a current antinode, the presence of even a single vortex leads to a measurable decrease in the quality factor and a dispersive shift of the resonant frequency. For modes with the vortex located at a current node, the presence of the vortex results in no detectable excess loss and, in fact, produces an increase in the quality factor. We attribute this enhancement to a reduction in the density of nonequilibrium quasiparticles in the resonator due to their trapping and relaxation near the vortex core.
The Hydrophobic Face Orientation of Apolipoprotein A-I Amphipathic Helix Domain 143–164 Regulates Lecithin:Cholesterol Acyltransferase Activation

Apolipoprotein A-I (apoA-I) activates the plasma enzyme lecithin:cholesterol acyltransferase (LCAT), catalyzing the rapid conversion of lipoprotein cholesterol to cholesterol ester. Structural mutants of apoA-I have been used to study the details of apoA-I-LCAT-catalyzed cholesterol ester formation. Several studies have shown that the alpha-helical segments corresponding to amino acids 143-164 and 165-186 (repeats 6 and 7) are essential for LCAT activation. In the present studies, we examined how the orientation of the hydrophobic face, independent of an increase in overall hydrophobicity, affects LCAT activation. We designed, expressed, and characterized a mutant, reverse of 6 apoA-I (RO6 apoA-I), in which the primary amino acid sequence of repeat 6 (amino acids 143-164) was reversed from its normal orientation. This mutation rotates the hydrophobic face of repeat 6 approximately 80 degrees. Lipid-free RO6 apoA-I showed a marked stabilization when denatured by guanidine hydrochloride, but showed significant destabilization to guanidine hydrochloride denaturation in the lipid-bound state compared with wild-type apoA-I. Recombinant high density lipoprotein discs (rHDL) formed from RO6 apoA-I, sn-1-palmitoyl-sn-2-oleoyl phosphati-dylcholine, and cholesterol were approximately 12 A smaller than wild-type apoA-I rHDL. The reduced size suggests that one of the repeats did not effectively participate in phospholipid binding and organization. The sn-1-palmitoyl-sn-2-oleoyl phosphatidylcholine RO6 rHDL were a less effective substrate for LCAT. Mapping the entire lipid-free and lipid-bound RO6 apoA-I with a series of monoclonal antibodies revealed that both the lipid-free and lipid-bound RO6 apoA-I displayed altered or absent epitopes in domains within and adjacent to repeat 6. Together, these results suggest that the proper alignment and orientation of the hydrophobic face of repeat 6 is an important determinant for maintaining and stabilizing helix-bilayer and helix-helix interactions.
Cervicothoracic complications of intravenous drug abuse

Abstract During a recent four month period, clinical and radiologic evaluation of four patients with inflammatory disease in the neck or upper mediastinum was performed. All patients admitted to attempting intravenous narcotic injections in the neck. Three patients were examined by computed tomography in addition to plain films and one patient was also examined angiographically. Complications in this group of patients included cellulitis, abscess, venous thrombosis and pneumothorax. Computed tomography appears to be the imaging modality ideally suited to the evaluation of these abnormalities.
Development of a Field Design for In Situ Gaseous Treatment of Sediment Based on Laboratory Column Test Data

A testing methodology is presented that supports the development of a field design for in situ gaseous treatment of sediments with diluted hydrogen sulfide. This approach involves the collection of column breakthrough test results at various flow rates, allowing a relationship to be developed between pore velocity of the carrier gas and velocity of the hydrogen sulfide reaction front that permits sizing to the field scale. A regression fit of a set of laboratory column breakthrough test data collected in this study is utilized to illustrate the development of a field design based on a two-dimensional radial flow analytical model. Information regarding treatment time and hydrogen sulfide consumption characteristics associated with in situ gaseous treatment can then be obtained from this model and used as a basis for estimation of treatment schedule and costs. The regression relationship can also be utilized in numerical models in more complex geometries to support the field design of in situ gaseous treatment operations.
Controversies in juvenile idiopathic arthritis-associated uveitis.

AbstractJuvenile idiopathic arthritis-associated uveitis (JIAU) accounts for a sizable proportion of uveitis cases in children and is an important cause of ocular morbidity in uveitis patients in this age group. The authors present the results of a survey conducted to obtain a better understanding of the current views and practices of ophthalmologists involved in the care of children with JIAU. A detailed questionnaire consisting of 54 questions addressing epidemiology, diagnosis, and therapy of JIAU was distributed to 67 uveitis specialists. The responses from 37 completed questionnaires were tabulated for this report. While the experts often agreed on aspects of the epidemiologic and clinical features of JIAU and its complications, considerable diversity of responses was noted—particularly with regard to practice patterns. Regarding diagnostics and disease monitoring, all experts favored ANA testing, whereas two-thirds also suggested HLA-B27 typing. Laser flare photometry was available to and routinely ...
Special Issue Overview: Optimizing Mixed Methods for Implementation Research in Large Systems

States and healthcare systems spend significant resources on mental and physical health services, are responsible for serving entire populations under their purview, and struggle to ensure that the services they provide are informed by the best available evidence. Consequently, implementation research has become a powerful branch of applied science with a focus on identifying strategies for improving the quality of population-based services. These large systems are multi-level, with clients nested within providers, providers nested within clinics or agencies, and agencies nested within state or healthcare systems that craft policies. Despite the development of numerous conceptual models and a small number of studies on phases and stages in implementing specific practices (Saldana 2014; Chamberlain et al. 2011; Olin et al. in press), very little attention has been directed towards offering solutions for the unique methodological challenges of research, particularly within large and complex state and healthcare systems.
Erosion of terrestrial planet atmosphere by surface motion after a large impact

The history of atmosphere accretion has a large significance in the evolution of the Earth and other planets. Here we present a quantitative analysis of the Earth's response to large impacts (in the 10^(32)–10^(38) erg energy range), and the resulting atmosphere loss owing to the global radial surface motion. Our results show that it is possible to deplete the Earth's atmosphere via this mechanism in very large (lunar-sized, ∼ 10^(38) erg) impacts.
Risk factors and predictors of mortality of methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia in HIV-infected patients

OBJECTIVES To define the incidence, risk factors and short-term predictors of mortality of methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia in HIV-infected patients. PATIENTS AND METHODS All HIV-infected subjects with S. aureus bacteraemia were consecutively enrolled in a case-control study between January 1, 1991 and December 31, 2000 and prospectively followed up. RESULTS In the study period, 129 of 419 (31%) HIV-infected patients with bacteraemia had a diagnosis of S. aureus bacteraemia. The comparative analysis of incidence of S. aureus bacteraemia in the period 1991-96 and 1997-2000 showed a significant decrease (P < 0.001). The same trend was observed for MRSA bacteraemia (P = 0.002). The analysis of antimicrobial resistance showed that among 129 S. aureus strains, 88 (68%) were methicillin susceptible and 41 (32%) were methicillin resistant. The majority of MRSA bacteraemia was hospital acquired (78%). Previous administration of beta-lactams (P < 0.001), multiple previous hospital admissions (P < 0.001) and low numbers of CD4+ peripheral cells (P < 0.001) were found to be independent risk factors of methicillin resistance at multivariate analysis. The mortality rate was 34% in the cases and 11% in the controls (P = 0.002). Multivariate analysis indicated that a high Acute Physiology and Chronic Health Evaluation (APACHE) III score (P < 0.001) and high HIV viraemia (P = 0.02), but not methicillin resistance, predicted an increased risk of death in patients with S. aureus bacteraemia. CONCLUSION Individual exposure to beta-lactams, in association with a history of multiple hospitalizations and low CD4+ cell number, plays a pivotal role as a risk factor for the development of methicillin resistance in HIV-infected patients. Methicillin resistance does not influence the outcome of S. aureus bacteraemia when included in a multivariate analysis.
Tracking the Actions and Possessions of Agents

We propose that there is a powerful human disposition to track the actions and possessions of agents. In two experiments, 3-year-olds and adults viewed sets of objects, learned a new fact about one of the objects in each set (either that it belonged to the participant, or that it possessed a particular label), and were queried about either the taught fact or an unrelated dimension (preference) immediately after a spatiotemporal transformation, and after a delay. Adults uniformly tracked object identity under all conditions, whereas children tracked identity more when taught ownership versus labeling information, and only regarding the taught fact (not the unrelated dimension). These findings suggest that the special attention that children and adults pay to agents readily extends to include inanimate objects. That young children track an object's history, despite their reliance on surface features on many cognitive tasks, suggests that unobservable historical features are foundational in human cognition.
Thermal Stability of Ultrathin Amorphous Carbon Films for Energy-Assisted Magnetic Recording

Energy-assisted magnetic recording (EAMR) uses a laser-optical system integrated into the magnetic head to heat locally a fine-grained material of high magnetic anisotropy energy density above its Curie temperature, and store single bits in very small areas without being limited by the superparamagnetic effect. However, localized laser heating may affect the thermal stability of the carbon overcoat of the hard disk. To examine the effect of laser heating on the overcoat thermal stability, ultrathin amorphous carbon (a-C) films of similar thickness (~ 3.6 nm) synthesized by filtered cathodic vacuum arc (FCVA) and chemical vapor deposition (CVD) were subjected to repetitive heating under different laser powers. Carbon hybridization and surface roughness of the a-C films were examined by Raman spectroscopy and atomic force microscopy, respectively. For the laser power range studied (150-300 mW), a-C films produced by the FCVA technique demonstrated superior thermal stability than CVD films of similar thickness. To investigate the possibility of further reducing the magnetic spacing, thinner (~ 0.9 nm) a-C films deposited by the FCVA method were subjected to the same laser heating conditions. Although the thermal stability of the FCVA-synthesized a-C films exhibited thickness dependence, even the thinner (~ 0.9 nm) FCVA film demonstrated higher thermal stability than the much thicker (~ 3.6 nm) CVD film. The results of this study illustrate the high potential of FCVA as a coating method for EAMR.
Dynamics of Circulating Progesterone Concentrations Before and During Luteolysis: A Comparison Between Cattle and Horses

The profile of circulating progesterone concentration is more dynamic in cattle than in horses. Greater prominence of progesterone fluctuations in cattle than in horses reflect periodic interplay in cattle between pulses of a luteotropin (luteinizing hormone; LH) and pulses of a luteolysin (prostaglandin F2alpha; PGF2alpha). A dose of PGF2alpha that induces complete regression of a mature corpus luteum with a single treatment in cattle or horses is an overdose. The overdose effects on the progesterone profile in cattle are an immediate nonphysiological increase taking place over about 30 min, a decrease to below the original concentration, a dose-dependent rebound 2 h after treatment, and a progressive decrease until the end of luteolysis. An overdose of PGF2alpha in horses results in a similar nonphysiological increase in progesterone followed by complete luteolysis; a rebound does not occur. An overdose of PGF2alpha and apparent lack of awareness of the rebound phenomenon has led to faulty interpretations on the nature of spontaneous luteolysis. A transient progesterone suppression and a transient rebound occur within the hours of a natural PGF2alpha pulse in cattle but not in horses. Progesterone rebounds are from the combined effects of an LH pulse and the descending portion of a PGF2alpha pulse. A complete transitional progesterone rebound occurs at the end of preluteolysis and the beginning of luteolysis and returns progesterone to its original concentration. It is proposed that luteolysis does not begin in cattle until after the transitional rebound. During luteolysis, rebounds are incomplete and gradually wane. A partial rebound during luteolysis in cattle is associated with a concomitant increase in luteal blood flow. A similar increase in luteal blood flow does not occur in mares.
Does Rotation Influence Double-Diffusive Fluxes in Polar Oceans?

AbstractThe diffusive (or semiconvection) regime of double-diffusive convection (DDC) is widespread in the polar oceans, generating “staircases” consisting of high-gradient interfaces of temperature and salinity separated by convectively mixed layers. Using two-dimensional direct numerical simulations, support is provided for a previous theory that rotation can influence DDC heat fluxes when the thickness of the thermal interface sufficiently exceeds that of the Ekman layer. This study finds, therefore, that the earth’s rotation places constraints on small-scale vertical heat fluxes through double-diffusive layers. This leads to departures from laboratory-based parameterizations that can significantly change estimates of Arctic Ocean heat fluxes in certain regions, although most of the upper Arctic Ocean thermocline is not expected to be dominated by rotation.
A case study in metals for inventions and innovations

An improved method for the measurement of innovation and innovative activity across long life cycles, especially where patentable technology plays a part in the innovation is studied in this article. In a previous publication we were able to distinguish four stages of a long life cycle. In this article we examine whether the patent life cycle and the production activity life cycle are related. Two conventional schools of thought commonly exist in reference to measurement of technical innovation, one suggesting the use of patents as the best indicator of innovative activity, and the other recommending alternative means, not using patent data. This article proposes a novel method of measurement utilizing yearly patent counts. A model was developed using twelve metals whose yearly production activity was correlated with patent counts associated with the same materials. This correlated data was then entered into best-fit equations to obtain fitted patent and activity life cycle curves. Differences in the origins of these fitted curves were interpreted as lags of time in the life cycle of the patent or activity thus allowing for comparisons between patents and innovation activity. The behavior of the number of patents with time was found to be similar to production growth, making patents a measure and representation of technical innovation. In conclusion we were able to categorize the metals into three groups. Group 1, containing chromium, magnesium, nickel and zirconium are metals whose patent activity is driving their production. Group 2, containing aluminum, copper, titanium and zinc are metals in which production is driving the patenting. Group 3, which is composed of the Stage IV metals iron, manganese, molybdenum and tungsten, represents materials that have no current innovative activity that can be measured or correlated to the patent activity. The results suggest a fertile field of future research extending the initial pattern equation model to include R&D, Patents, and Performance.
Role of the Core Region of the PufX Protein in Inhibition of Reconstitution of the Core Light-Harvesting Complexes of Rhodobacter sphaeroides and Rhodobacter capsulatus†

PufX, the protein encoded by the pufX gene of Rhodobacter capsulatus and Rhodobacter sphaeroides, has been further characterized. The mature forms of these proteins contain 9 and 12 fewer amino acids, respectively, at the C-terminal end of the protein than are encoded by their pufX genes. To identify the portion of PufX responsible for inhibition of LH1 formation in reconstitution experiments, different regions (N-terminus and several core regions containing different lengths of the C-terminus) of Rb. sphaeroides and Rb. capsulatus PufX were chemically synthesized. Neither the N- nor C-terminal polypeptides of Rb. sphaeroides were inhibitory to LH1 reconstitution. However, all core segments were active, causing 50% inhibition at a concentration ratio of between 3:1 and 6:1 relative to the LH1 α-polypeptides whose concentrations were 3−4 μM. CD measurements indicated that the core segment containing 39 amino acids of Rb. sphaeroides PufX exhibited 47% α-helix in trifluoroethanol while the core segment cont...
The preventable proportion of type 2 diabetes by ethnicity: the multiethnic cohort.

Purpose To estimate the population-attributable risk (PAR) associated with modifiable risk factors for diabetes among Caucasians, Native Hawaiians, and Japanese Americans in the Hawaii component of the Multiethnic Cohort. Methods This analysis is based on 74,970 cohort participants ages 45-75 years who completed a questionnaire on demographics, diet, and lifestyle factors in 1993-1996. After a mean follow-up time of 12.1 (0.01-14.4) years, 8559 diabetes cases were identified by self-report, a medication questionnaire, and through health plan linkages. Hazard ratios for diabetes and partial PARs for single and different combinations of modifiable risk factors were estimated. Results Overweight, physical inactivity, high meat intake, no alcohol consumption, and smoking were positively associated with diabetes risk in all ethnic groups. The estimated PARs suggested that among men, 78%, and among women, 83%, of new diabetes cases could have been avoided if all individuals had been in the low risk category for all of the modifiable risk factors. The slightly lower PARs in Japanese Americans were not significantly different from those in Caucasian and Native Hawaiian subjects. Conclusions Although PARs varied slightly over ethnicity, our findings do not support ethnic-specific prevention strategies; interventions targeted at multiple behaviors are needed in all ethnic groups.
Genetics of arginine biosynthesis in Neurospora crassa.

A large number of arginine-requiring mutants of Neurospora was isolated, using a strain already partially impaired in an enzyme of the pathway. Among the mutants, all previously described loci, except one, were represented, and several new loci were defined and mapped. Four groups of mutants were of particular interest. First, the large group of arg-6 mutants, when tested for intragenic complementation, suggested a bifunctional gene, possibly controlling two steps in ornithine synthesis. This is consistent with the limited enzymic information about this locus. Second, the arg-13 locus was represented by 14 new mutants. All five tested were quite leaky, suggesting that the function controlled by this gene can be carried out to a limited extent spontaneously or by another gene product. Third, a new locus, arg-14, was defined. It controls a step in ornithine synthesis. It lies in a 1 to 2 map-unit interval between arg-2 and pyr-3 on LG IVR, as shown by mapping in relation to translocation breakpoints. Fourth, a second new locus whose mutants render the partial mutation in starting material auxotrophic was defined and mapped near the centromere of LG VIL. These new mutants are unable to derepress enzymes of the pathway and may qualify as regulatory mutants.
Frameworks for learner assessment in medicine: AMEE Guide No. 78

In any evaluation system of medical trainees there is an underlying set of assumptions about what is to be evaluated (i.e., which goals reflect the values of the system or institution), what kind of observations or assessments are useful to allow judgments 1 ; and how these are to be analyzed and compared to a standard of what is to be achieved by the learner. These assumptions can be conventionalized into a framework for evaluation. Frameworks encompass, or ‘‘frame,’’ a group of ideas or categories to reflect the educational goals against which a trainee’s level of competence or progress is gauged. Different frameworks provide different ways of looking at the practice of medicine and have different purposes. In the first place, frameworks should enable educators to determine to what extent trainees are ready for advancement, that is, whether the desired competence has been attained. They should provide both a valid mental model of competence and also terms to describe successful performance, either at the end of training or as milestones during the curriculum. Consequently, such frameworks drive learning by providing learners with a guide for what is expected. Frameworks should also enhance consistency and reliability of ratings across staff and settings. Finally, they determine the content of, and resources needed for, rater training to achieve consistency of use. This is especially important in clinical rotations, in which reliable assessments have been most difficult to achieve. Because the limitations of workplace-based assessment have persisted despite the use of traditional frameworks (such as those based on knowledge, skills, and attitudes), this Guide will explore the assumptions and characteristics of traditional and newer frameworks. In this AMEE Guide, we make a distinction between analytic, synthetic, and developmental frameworks. Analytic frameworks deconstruct competence into individual pieces, to evaluate each separately. Synthetic frameworks attempt to view competence holistically, focusing evaluation on the performance in real-world activities. Developmental frameworks focus on stages of, or milestones, in the progression toward competence. Most frameworks have one predominant perspective; some have a hybrid nature.
Double explosions and jet formation in gamma-ray burst–supernova progenitors

Progenitors of long gamma-ray bursts (GRBs), and of core-collapse supernovae in general, may have two separate mechanisms driving the outflows: quasi-isotropic neutrino-driven supernova explosions followed by a highly collimated relativistic outflow driven by the GRB central engine, a black hole or a magnetar. We consider the dynamics of the second GRB-driven explosion propagating through the expanding envelope generated by the passage of the primary supernova shock. Beyond the central core, in the region of steep density gradient created by the supernova shock breakout, the accelerating secondary quasi-spherical GRB shock becomes unstable to corrugation and under certain conditions may form a highly collimated jet, a 'chimney', when a flow expands almost exclusively along a nearly cylindrically collimated channel. Thus, weakly non-spherical driving and/or non-spherical initial conditions of the wind cavity may produce highly non-spherical, jetted outflows. For a constant luminosity GRB central engine, this occurs for density gradient in the envelope ρ ∝ r -ω steeper than ω > 4.
Laparoscopy in the Contemporary Management of Acute Appendicitis

Abstract Background We sought to compare laparoscopic appendectomy (LA) with open appendectomy (OA) focusing on the negative appendectomy rate (NAR), emergency department (ED) to operating room (OR) time, procedure length, and histopathological correlation. Methods All appendectomies for appendicitis over a 6-year period at a single hospital were reviewed. Open and laparoscopic procedures were compared. Results There were 1,312 appendectomies (54.6% OA and 45.4% LA) Mean ED to OR time was as follows: LA 10.8 hours (standard deviation [SD] ± 9.0) versus 9.8 hours (SD ± 8.5) OA ( P = .0333). Mean OR time was 61.2 minutes (SD ± 29.1) LA versus 57.7minutes (SD ± 28) OA ( P = .0293). NAR was 18.3%, LA 23.3% versus14.0% OA ( P P = .0003). In the LA group, 9.9% with a "normal" appendix had appendicitis by histopathology. Conclusions LA is associated with increased presentation to procedure time, operative time, and negative appendectomy rate. Removing a "normal" appendix during LA in the absence of alternate pathology is recommended.