cssi/SciSciGPT-SciSciNet huggingface dataset:
Role of catheter mapping in the preoperative evaluation of ventricular tachycardia

Although surgery is an accepted mode of therapy for refractory ventricular tachycardia, routine aneurysmectomy has yielded unpredictable results. This is believed to have occurred because there was no documentation that the arrhythmia actually arose from resected aneurysmal tissue. Catheter endocardial mapping has been used to localize preoperatively the area of origin of the arrhythmia. This technique has established that the arrhythmias arise near the endocardium at the borders of the aneurysm or infarction, or both. These regions, particularly when they occur in the interventricular septum, are not resected by standard aneurysmectomy. Intraoperative endocardial and epicardial mapping have validated the accuracy of this technique. We believe that catheter mapping should be performed before surgery for the following reasons: (1) In some patients ventricular tachycardia is not inducible in the operating room (for example, automatic ventricular tachycardia can be mapped in the catheterization laboratory); (2) in some patients not all morphologic forms of tachycardia can be induced or mapped intraoperatively because of failure of inducibility, time constraints or degeneration of the arrhythmia to ventricular fibrillation; and (3) intraoperative endocardial mapping occasionally cannot be performed because of lack of technical skills, physical factors such as mural thrombosis, or the inability to induce ventricular tachycardia after aneurysmectomy. Other methods currently being evaluated to localize the origin of ventricular tachycardia that do not require induction of arrhythmia are analysis of ventricular electrograms during sinus rhythm and pacemapping.
Hypothermia Induces T-Cell Production of Immunosuppressive Cytokines

Abstract Background. Hypothermia is associated with increased postoperative infectious complications. We hypothesized that hypothermia suppresses the inflammatory response by altering T-cell cytokine production from a proinflammatory to an antiinflammatory profile, thus explaining the increased susceptibility to infectious complications associated with perioperative hypothermia. Methods. Forty rats were randomized to either a Hypothermia (30°C) or Control (38°C) group. Blood samples taken at baseline and after 8 h of thermoregulation were stimulated with phorbol 12-myristate 13-acetate and ionomycin. Interleukin (IL)-2 receptor expression and intracellular IL-10 production were measured using monoclonal antibodies and flow cytometry in CD4 and CD8 T cells. Differences in IL-10 production and IL-2 receptor expression for stimulated samples in the Hypothermia and Control groups were compared. Results. Stimulated CD4 cells demonstrated an antiinflammatory cytokine expression profile after hypothermia. Intracellular IL-10 production increased in the Hypothermia group but remained the same in the Control group (% change = 40 [3,87] and 2 [−36,26], respectively; P = 0.043). The increase in IL-2 receptor expression observed in the control group was suppressed after hypothermia (% change = 12[8,30] and 1 [−3,13], respectively; P = 0.026). We observed a greater increase in IL-10 production by CD8 cells from hypothermic animals than in those from control animals (% change = 41 [−8,90] and −4 [−40,5], respectively; P = 0.019). CD8 IL-2 receptor expression in hypothermic animals was similar to that of control animals (% change = 23 [−7,37] vs 25 [2,80], respectively; P = 0.32). Conclusions. Hypothermia induced an antiinflammatory T-cell cytokine profile.
FMRI Measurement of CNS Responses to Naloxone Infusion and Subsequent Mild Noxious Thermal Stimuli in Healthy Volunteers

The aims of this study were to assess the effects of a μ-opioid antagonist, naloxone, on endogenous opioid systems and to evaluate the effect of naloxone on the CNS response to mild noxious heat. D...
Arterial Thrombin Activity After Angioplasty in an Atherosclerotic Rabbit Model Time Course and Effect of Hirudin

Background A 2-hour infusion of the direct thrombin inhibitor hirudin at the time of balloon angioplasty limits restenosis in the focally atherosclerotic rabbit. Although short-term administration of hirudin may have a prolonged biological effect, the effect of hirudin on vessel thrombin activity has not been previously studied in an animal model of angioplasty. We hypothesized that a short intravenous infusion of hirudin would result in prolonged inhibition of arterial wall–associated thrombin activity (ATA) after angioplasty. Methods and Results Sixty-one rabbits received recombinant hirudin (r-hirudin) (1 mg/kg bolus plus 1 mg · kg−1 · h−1×2 hours) or bolus heparin (controls, 150 U/kg) intravenously at the time of femoral balloon angioplasty. ATA was measured through exposure of arterial segments ex vivo to fibrinogen and conducting an assay for fibrinopeptide A (FPA). ATA was low in nonballooned, atherosclerotic vessels (FPA=0.5±0.3 ng · mL−1 · mg−1) but increased significantly at 24 hours after angio...
Word frequency and selection strategies in verbal-discrimination learning

Selection strategies for enhancing or hindering the establishment of functional stimuli related to the consistent selection of intrapair right items in verbal-discrimination learning were investigated by means of various transfer conditions. Specific item content of the two lists was unrelated. However, a strategy activated during List 1 practice that was based on the pre-experimental word-frequency attributes of wrong and right items in the list was found to transfer to performance on List 2.
Role of the Autonomic Nervous System in Modulating Cardiac Arrhythmias

The autonomic nervous system plays an important role in the modulation of cardiac electrophysiology and arrhythmogenesis. Decades of research has contributed to a better understanding of the anatomy and physiology of cardiac autonomic nervous system and provided evidence supporting the relationship of autonomic tone to clinically significant arrhythmias. The mechanisms by which autonomic activation is arrhythmogenic or antiarrhythmic are complex and different for specific arrhythmias. In atrial fibrillation, simultaneous sympathetic and parasympathetic activations are the most common trigger. In contrast, in ventricular fibrillation in the setting of cardiac ischemia, sympathetic activation is proarrhythmic, whereas parasympathetic activation is antiarrhythmic. In inherited arrhythmia syndromes, sympathetic stimulation precipitates ventricular tachyarrhythmias and sudden cardiac death except in Brugada and J-wave syndromes where it can prevent them. The identification of specific autonomic triggers in different arrhythmias has brought the idea of modulating autonomic activities for both preventing and treating these arrhythmias. This has been achieved by either neural ablation or stimulation. Neural modulation as a treatment for arrhythmias has been well established in certain diseases, such as long QT syndrome. However, in most other arrhythmia diseases, it is still an emerging modality and under investigation. Recent preliminary trials have yielded encouraging results. Further larger-scale clinical studies are necessary before widespread application can be recommended.
Opposing Regulation of Pair Bond Formation by cAMP Signaling within the Nucleus Accumbens Shell

The formation of monogamous pair bonds, by prairie voles, is facilitated by activation of dopamine (DA) D2-like, but not D1-like, receptors within the nucleus accumbens (NAcc) shell. Because DA exerts opposing regulation of cAMP production depending on the subtype of receptor activated, we tested the hypothesis that DA regulation of pair bond formation is mediated via the cAMP signaling cascade. Consistent with activation of D2-like receptors, decreasing cAMP signaling, by blocking cAMP binding sites on protein kinase A (PKA), facilitated partner preference formation. Conversely, increasing cAMP signaling, by preventing the activation of inhibitory G-proteins, activating stimulatory G-proteins, or stimulating PKA prevented the formation of mating-induced partner preferences. These manipulations were effective in the shell, but not the core, of the NAcc. Together, these data demonstrate opposing regulation over pair bond formation by cAMP signaling within the NAcc shell.
Electric utilities, fuel use, and responsiveness to fuel prices

This research tests the impact of changes in fuel price to explain fuel use by electric utilities. We employ a three-stage least squares model that explains changes in fuel use as a function of changes in three fuel prices. This model is repeated across sub-samples of data aggregated at the plant level and operating holding company level. We expect that plants and holding companies reduce fuel use when fuel prices rise. Several fuel substitution effects within and across plants and holding companies are demonstrated, as well as several frictions. At the plant level, higher prices of natural gas lead to less natural gas consumption, less coal consumption, and more fuel oil consumption. At the operating holding company level, results demonstrate the inelasticity of coal use and the increases of natural gas in response to higher coal prices. Subsamples demonstrate heterogeneity of results across different plants. Results emphasize that technological, market, and regulatory frictions may hinder the performance of energy policies.
3D nanovision for the inspection of micro-electro-mechanical systems

Micro-electro-mechanical systems (MEMS) are found in area applications such as the automotive industry, the aviation industry, the semiconductor industry, the medical field, and various other fields where miniaturization is taking over. The accurate measurement of features on the surface of MEMS is an important tool for the assessment and monitoring of product quality. Presented here are the algorithms and results of 3D model reconstructions of MEMS devices using a variety of microscopic sensors. These sensors include an atomic force microscope, a scanning electron microscope, and a laser scanning confocal microscope. MEMS devices with micron-size features were first scanned with these microscopes. 3D models were then built and visualized using methods specific to each microscope. This allows for the models use in applications such as inspection, study of wear and tear, behavior, and reaction of such systems to pressure, heat, and friction.
Oxidative stress inhibits vascular KATP channels by S-glutathionylation

The KATP channel is an important player in vascular tone regulation. Its opening and closure lead to vasodilation and vasoconstriction, respectively. Such functions may be disrupted in oxidative stress seen in a variety of cardiovascular diseases, while the underlying mechanism remains unclear. Here, we demonstrated that S-glutathionylation was a modulation mechanism underlying oxidant-mediated vascular KATP channel regulation. An exposure of isolated mesenteric rings to hydrogen peroxide (H2O2) impaired the KATP channel-mediated vascular dilation. In whole-cell recordings and inside-out patches, H2O2 or diamide caused a strong inhibition of the vascular KATP channel (Kir6.1/SUR2B) in the presence, but not in the absence, of glutathione (GSH). Similar channel inhibition was seen with oxidized glutathione (GSSG) and thiol-modulating reagents. The oxidant-mediated channel inhibition was reversed by the reducing agent dithiothreitol (DTT) and the specific deglutathionylation reagent glutaredoxin-1 (Grx1). Consistent with S-glutathionylation, streptavidin pull-down assays with biotinylated glutathione ethyl ester (BioGEE) showed incorporation of GSH to the Kir6.1 subunit in the presence of H2O2. These results suggest that S-glutathionylation is an important mechanism for the vascular KATP channel modulation in oxidative stress.
Seed bank potential of moist-soil managed wetlands in east-central Texas

Proper management techniques on moist-soil wetlands provide methods for enhancement of established wetlands, restoration of former wetlands, and creation of new wetland habitat. These techniques also create suitable wetland habitat for non-breeding waterfowl and other wetland dependent species during winter. To understand moist-soil managed wetland vegetative patterns, aspects such as plant species distribution, reproductive strategy, seed bank composition and viability should be thoroughly characterized. We investigated soil seed bank potential of moist-soil managed wetlands on Richland Creek Wildlife Management Area, Texas to determine which treatment (i.e., drawdown or flooded) produced the most desirable moist-soil plants. A total of 27 species germinated, producing 3,731 and 3,031 seedlings in drawdown and flooded treatments, respectively. There were also differences in stem densities between treatments of desirable and non-desirable species. Drawdown treatments had more seedlings germinate than flooded treatments, validating the notion that drawdown treatments provide favorable conditions for seed germination. Drawdown and flooding techniques, when properly timed, will allow managers to drive and directly influence managed wetland plant communities based on seed bank composition and response to presence or absence of water during the germination period.
METAL UTILIZATION FROM CASEIN AND SOY BASED DIETS AS AFFECTED BY TRIPOLYPHOSPHATE AND HEXAMETAPHOSPHATE.

Abstract Rats were fed casein- or soy based diets, both either free of polyphosphates or with 0.5% tripolyphosphate or hexametaphosphate incorporated. Both polyphosphates increased zinc absorption and utilization from both diets; the greatest effect was exerted in the soy diet, where tripolyphosphate was more effective. Both polyphosphates enhanced the absorption and liver accumulation of iron, but tripolyphosphate depressed femur iron levels, especially in the soy-fed animals. Tripolyphosphate reduced calcium and mangesium bioavailability, and both polyphosphates decreased urinary calcium, magnesium and fluid excretion. These effects were most pronounced in the soy-tripolyphosphate group, where renal calcification was found, but disappeared in all groups by the end of 15 days.
Frequency and dependence of long range temporal correlations in human hippocampal energy fluctuations

Spontaneous energy fluctuations in human hippocampal EEG show prominent amplitude and temporal variability. Here we show hippocampal energy fluctuations often exhibit long-range temporal correlations with power-law scaling. In most cases this scaling behavior persisted on time scales in excess of 10 minutes, the maximum duration we could detect with our recording durations. During these epochs we find that the energy fluctuations exhibit long-range correlations over a broad frequency range (0.5‐100 Hz) with greater persistence of the correlations in the lower frequency bands (0.5‐30 Hz) than the higher (30‐100 Hz). The correlation in hippocampal energy fluctuations is characterized by a bias for energy fluctuations to be followed by similar magnitude fluctuations over all energy scales, i.e. large fluctuations begets large fluctuations and small begets small. © 2005 Wiley Periodicals, Inc. Complexity 10: 35‐44, 2005
Acute pressure dependence of the electron ionization mass spectrum of molybdenyl acetylacetonate

Formation of both fragment and polymeric ions observed in the electron impact mass spectrum of molybdenyl acetylacetonate exhibit a strong dependence on the instantaneous pressure in the ionization source. The indicated source pressure increases with increasing direct probe temperature. Utilizing a probe temperature increase of only 30°C min−1, the relative abundances of some ions can change by factors as high as 15 over a period of 60 s. Some ions are remarkably transient, appearing in only the few scans during which the source pressure corresponds to just that required for their formation. These rapid changes in the ion relative abundances are also exhibited in tandem mass spectra, and especially in parent ion scans.
Advances in Development of J-Integral Experimental Estimation, Testing and Standardization

The J-integral is an important concept in the elastic-plastic fracture mechanics, and serves as a critical material parameter to quantify the toughness or resistance of ductile materials against fracture. The relation between the J-integral and crack extension has been widely used as the resistance curve of ductile materials in fracture mechanics design and in structural integrity assessment. Experimental testing and evaluation have played a central role in providing reliable fracture toughness properties to fracture mechanics analysis. Since the J-integral concept was proposed, extensive efforts of investigations have been made to develop its experimental estimation method, testing technique and standardization, as evident in the ASTM E1820 — a commonly used fracture toughness testing standard. In recent years, significant progresses of the J-integral fracture testing and experimental estimation have been achieved, and a part of them was accepted and updated in ASTM E1820. To better understand and use this fracture testing standard, the present paper gives a brief review of historical efforts and recent advances in the development of the J-integral experimental estimation and standard testing.Copyright © 2011 by ASME
The Glycoprotein Precursor Gene of Junin Virus Determines the Virulence of the Romero Strain and the Attenuation of the Candid #1 Strain in a Representative Animal Model of Argentine Hemorrhagic Fever

ABSTRACT The New World arenavirus Junin virus (JUNV) is the causative agent of Argentine hemorrhagic fever (AHF), a potentially deadly disease endemic to central regions of Argentina. The live-attenuated Candid #1 (Can) strain of JUNV is currently used to vaccinate the human population at risk. However, the mechanism of attenuation of this strain is still largely unknown. Therefore, the identification and functional characterization of viral genetic determinants dictating JUNV virulence or attenuation would significantly improve the understanding of the mechanisms underlying AHF and facilitate the development of novel, more effective, and safer vaccines. Here, we utilized a reverse genetics approach to generate recombinant JUNV (rJUNV) strains encoding different gene combinations of the pathogenic Romero (Rom) and attenuated Can strains of JUNV. All strains of rJUNV exhibited in vitro growth kinetics similar to those of their parental counterparts. Analysis of virulence of the rJUNV in a guinea pig model of lethal infection that closely reproduces the features of AHF identified the envelope glycoproteins (GPs) as the major determinants of pathogenesis and attenuation of JUNV. Accordingly, rJUNV strains expressing the full-length GPs of Rom and Can exhibited virulent and attenuated phenotypes, respectively, in guinea pigs. Mutation F427I in the transmembrane region of JUNV envelope glycoprotein GP2 has been shown to attenuate the neurovirulence of JUNV in suckling mice. We document that in the guinea pig model of AHF, mutation F427I in GP2 is also highly attenuating but insufficient to prevent virus dissemination and development of mild clinical and pathological symptoms, indicating that complete attenuation of JUNV requires additional mutations present in Can glycoprotein precursor (GPC). IMPORTANCE Development of antiviral strategies against viral hemorrhagic fevers, including AHF, is one of the top priorities within the Implementation Plan of the U.S. Department of Health and Human Services Public Health Emergency Medical Countermeasures Enterprise. Live-attenuated Candid #1 strain, derived from the 44th mouse brain passage of the prototype XJ strain of JUNV, has been demonstrated to be safe, immunogenic, and highly protective and is currently licensed for human use in Argentina. However, the bases for the attenuated phenotype of Candid #1 have not been established. Therefore, the identification and functional characterization of viral genetic factors implicated in JUNV pathogenesis and attenuation would significantly improve the understanding of the molecular mechanisms underlying AHF and facilitate the development of novel antiviral strategies.
Comparison of the late HI histone genes of the sea urchins Lytechinus pictus and Strongelocentrotus purpuratus

We have isolated and sequenced a gene encoding a late H1 histone subtype from the sea urchin species L. pictus. The primary structure of the late H1 subtype encoded by this gene is 209 amino acids in length, and has a net positive charge of 67. This gene is present in a single copy per haploid genome and encodes an mRNA of 752 nucleotides. Late H1 transcripts are detected in the unfertilized egg and are most prevalent in gastrulating embryos. Comparison of 375 bp of 5' flanking sequences of the L. pictus late H1 gene and the H1-gamma gene of a distantly related sea urchin species, S. purpuratus, reveals large blocks of sequences that are identical between the two genes. To determine if these conserved 5' sequences are present in other members of the sea urchin H1 gene family, the analogous region of S. purpuratus H1-alpha, an early H1 gene, was sequenced. The homology between the flanking sequences of the early and late families was limited to consensus sequences which are found upstream of all H1 genes. The possible regulatory implications of these findings are discussed.
Acculturation, weight status, and eating habits among Chinese-American preschool children and their primary caregivers: a pilot study

Abstract This study investigated acculturation, eating habits, and weight status among 53 Chinese-American children and their primary caregivers. Caregivers' mean acculturation score was 2.1, indicating low acculturation. Caregivers' mean body mass index (BMI) was 23.3; 21% were overweight (BMI ≥ 25). Children's mean BMI was 16.6; 17% were overweight (BMI ≥ 95th percentile). The food groups most commonly consumed at the child care center were dairy (15%), mixed dishes (15%), fruits (13%), 100% fruit juice (13%), and vegetables (11%). Of the food groups consumed at home, 43% reflected Chinese food, 26% reflected American food, and 31% reflected food that were shared by both cultures. Of the Chinese food, 26% were mixed dishes, 23% were bread, 16% were vegetables, 11% were meat, and 11% were soup. For American food consumed at home, 19% were desserts, 14% were sweetened beverages, and 11% were bread. Understanding acculturation, eating habits, and weight status of Chinese-American families is critical for designing and monitoring nutrition programs for this understudied population.
Linear chromosomal physical and genetic map of Borrelia burgdorferi, the Lyme disease agent

A physical map of the 952 kbp chromosome of Borrelia burgdorferi Sh-2-82 has been constructed. Eighty-three intervals on the chromosome, defined by the cleavage sites of 15 restriction enzymes, are delineated. The intervals vary in size from 96 kbp to a few hundred bp, with an average size of 11.5 kbp. A striking feature of the map is its linearity; no other bacterial groups are known to have linear chromosomes. The two ends of the chromosome do not hybridize with one another, indicating that there are no large common terminal regions. The chromosome of this strain was found to be stable in culture; passage 6, 165 and 320 cultures have identical chromosomal restriction maps. We have positioned all previously known Borrelia burgdorferi chromosomal genes and several newly identified ones on this map. These include the gyrA/gyrB/dnaA/dnaN gene cluster, the rRNA gene cluster, fla, flgE, groEL (hsp60), recA, the rho/hip cluster, the dnaK (hsp70)/dnaJ/grpE cluster, the pheT/pheS cluster, and the genes which encode the potent immunogen proteins p22A, p39 and p83. Our electrophoretic analysis detects five linear and at least two circular plasmids in B. burgdorferi Sh-2-82. We have constructed a physical map of the 53 kbp linear plasmid and located the operon that encodes the two major outer surface proteins ospA and ospB on this plasmid. Because of the absence of functional genetic tools for this organism, these maps will serve as a basis for future mapping, cloning and sequencing studies of B. burgdorferi.
Physical properties of coarse aerosol particles and haze elements in polluted urban-marine environment

Abstract Measurements of coarse particles (with r ≥ 1.0 μm) with the aid of a cascade impactor and of particle (droplet) identification in sensitized gelatine layers reveal their mean concentration of about 1.5 cm −3 during the months of May and June 20 km west from Napoli in Italy. Haze particles (droplets) are usually featured by insoluble core and many small particles deposited on their surface. Sea salt aerosol does not play a dominant role in the haze element formation at this site of measurement.
In vitro fertilization and childhood retinoblastoma

Aims To estimate the frequency of childhood retinoblastoma among children conceived by in vitro fertilization (IVF). Methods Using the United Kingdom-based General Practice Research Database (GPRD), we identified all live births, cases of retinoblastoma and IVF procedures occurring between January 1989 and December 2001. Results We identified 0 cases of retinoblastoma among 176 children conceived by IVF (Risk = 0/176, one-sided 97.5% CI 0, 0.02) and 24 cases of retinoblastoma diagnosed before age 5 years among 358 094 children not conceived by IVF (6.7 cases per 100 000 births [95% CI 4.5, 10]). Conclusions These data provide some reassurance that children born as a result of IVF are not at markedly increased risk of retinoblastoma.
Medications in neonatal resuscitation

Medication usage in neonatal resuscitation has been largely extrapolated from adult resuscitation guidelines. Compared to older children and adults, newborn infants have major anatomical and physiological differences which affect their need for and response to medications during resuscitation. This article discusses some of these differences, highlights the discussion of the Emergency Cardiac Care Panel for Neonatal Pharmacology, lists the recommendations of the panel to the Emergency Cardiac Care Committee, and discusses areas of future research in neonatal resuscitation.
Neuromuscular blocking action of verapamil in cats

The effects of the calcium (slow) channel blocker verapamil, on non-cardiac excitable membranes were examined in vivo. In barbiturate anaesthetized cats, the effect of intravenously administered verapamil (0.1, 0.2, and 0.4 mg*kg-1) on isometric twitch amplitude of the flexor carpi radialis muscle, elicited by indirect and direct electrical stimulation, was determined. At all doses tested, verapamil significantly reduced muscle twitch amplitude from control values. The effect of dosage on twitch reduction was far more pronounced for indirect than direct stimulation. Full recovery to control was observed by 90 minutes only with the lowest dose (0.1 mg*kg-1IV). Reduction of twitch amplitude (direct and indirect) lasted the duration of the experiment (180 minutes) for the two higher doses of verapamil. No significant changes in blood pressure, cardiac rate or rhythm were observed. The specific site and mechanism of verapamil’s neuromuscular blocking action remains unclear. In clinical situations where potent inhalation agents, adjuncts or neuromuscular blocking agents may be used, therapeutic doses of verapamil may interact to promote muscle weakness.
Applications in precision machining - factors in ns/ps choice

As the need for precision machining has grown, especially, to enable advances in smaller, faster, lower power consumption micro-electronics products, so have the capabilities in industrial lasers capable of high precision machining. One of the most important application decisions is related to the choice of ns regime or ps regime lasers. The appeal for higher precision, lower HAZ (heat affected zone) as well as layer selectivity offers new capability. We will cover key aspects of ns vs. ps choice and examples of good fit for each in key micro-electronics applications.
Synthesis of δ-stearolactone from oleic acid

δ-Stearolactone was prepared from oleic acid using concentrated sulfuric acid under various conditions in the presence of polar, nonparticipating solvents. δ-Stearolactone was formed in as high as 15∶1 ratios over the thermodynamic product, ψ-lactone, in the presence of methylene chloride, 100% wt/vol, at room temperature with two equivalents of sulfuric acid for 24 h. This procedure is applicable to other olefinic fatty acids such as estolides and fatty acid methyl esters. Temperature plays a role in the regioselectivity of the cyclization for δ-lactone, as lower temperatures (20°C) gave higher σ/ψ ratios. At higher temperatures (50°C) in the presence of sulfuric acid and methylene chloride the yield of lactone was 75% but with a σ/ψ ratio of only 0.3∶1. Cyclization of oleic acid to lactone also occurred with other acids. Oleic acid underwent reaction with perchloric acid, one equivalent, in the absence of solvent at 50°C, which yielded σ-lactone in a modest yield with a 3.1 σ/ψ ratio. The same temperature effect was observed with perchloric acid that was observed in the case of sulfiric acid. Because σ-stearolactone is much more reactive than the corresponding fatty acid, fatty acid ester, or ψ-lactone, we believe that it will be a useful synthon for many new industrial products including new biodegradable detergents.
Obesity in albino mice due to single injections of goldthioglucose.

SummaryMarked weight gains were produced in stock albino mice by single injections of goldthioglucose. Analysis of total body lipids, protein, water, and ash showed these weight gains to be primarily due to an increase in adipose tissue. This obesity occurred in approximately one-third of the survivors of sublethal doses of goldthioglucose. Except for centrolubular fatty infiltration of the liver in obese animals, no-anatomic lesions were found in the organs examined.
Reconsidering the effects of seat belt laws and their enforcement status

The debate over the benefits of mandatory seat belt laws and their enforcement status has focused on a controversial empirical enigma: why have these policies, which appear to have increased belt use sharply, had a relatively small impact on traffic fatalities? In this paper, I offer new insights into this question by examining panel data on observed belt use from the National Highway Traffic Safety Administration and self-reported data on belt use from pooled cross-sections of the Centers for Disease Control and Prevention's 1985-1993 Behavioral Risk Factor Surveillance System. By exploiting the panel nature of these data, I demonstrate that prior estimates, which have not conditioned on the unobserved time-varying determinants of belt use, have dramatically overestimated the impact of seat belt laws and their enforcement status on belt use. The true effects are more consistent with the modest impact these policies have had on traffic fatalities without having to appeal to the possibility of risk compensation by drivers. However, I find strong evidence in support of the selective recruitment hypothesis. Belt use among those most likely to be involved in traffic accidents (e.g. males, drinkers of alcohol, the young) has been significantly less responsive to seat belt laws and their enforcement status.
Gendered water spaces: a study of the transition from wells to handpumps in Mozambique

In many parts of rural Africa, women and children spend a lot of time collecting water. In the development literature, the water collection task is portrayed as oppressive, arduous, and disliked by women. Eliminating this activity from women's lives is believed to empower them, yet there has been little research investigating what actually happens at the water source or how women themselves perceive the time spent there. This research is based on one year of ethnographic fieldwork in five rural communities in the northern province of Nampula, Mozambique. Over this year, handpumps were constructed in communities where people previously collected water from distant shallow wells and rivers. This article compares the social interactions and activities between the customary water sites and the handpump through the lens of gendered space. The customary water sites are controlled by women and highly valued for their social attributes. While clean water is more accessible at the handpumps, men often regulate acc...
Quantum nonlinear optics: Tailored single photons

A convenient optical scheme for compressing the bandwidth and tuning the frequency of single photons could allow photon qubits to be used in matter-based quantum memories. This development is also an important step towards arbitrary waveform generation of quantum states of light.
Mouse Glucocorticoid Receptor Phosphorylation Status Influences Multiple Functions of the Receptor Protein

Although studies have shown that the mouse glucocorticoid receptor (mGR) contains eight phosphorylation sites (Bodwell, J. E., Orti, E., Coull, J. M., Pappin, D. J. C., Smith, L. I., and Swift, F. (1991) J. Biol. Chem. 266, 7549-7555), the effect of phosphorylation on receptor function is unclear. We have examined the consequences of single or multiple phosphorylation site mutations on several properties of mGR including receptor expression, ligand-dependent nuclear translocation, hormone-mediated transactivation, ligand-dependent down-regulation of mGR, and receptor protein half-life. Mutations had little effect on receptor expression, subcellular distribution, ligand-dependent nuclear translocation, or on the ability to activate hormone-mediated transcription from a complex (murine mammary tumor virus) promoter. In contrast, the phosphorylation status of the mGR had a profound effect on the ability to transactivate a minimal promoter containing simple glucocorticoid response elements after hormone administration. Similarly, ligand-dependent down-regulation by glucocorticoids of both receptor mRNA and protein was abrogated in mutants containing three or more phosphorylation site alterations. Finally, we show that the phosphorylation status of mGR has a profound effect on the stability of the glucocorticoid receptor protein. Receptors containing seven or eight mutated sites have a markedly extended half-life and do not show the ligand-dependent destabilization seen with wild type receptor. These data show that receptor phosphorylation may play a crucial role in regulating receptor levels and hence control receptor functions.
Problem-solving, proving, and learning: The relationship between problem-solving processes and learning opportunities in the activity of proof construction

Abstract In university mathematics courses, the activity of proof construction can be viewed as a problem-solving task in which the prover is asked to form a logical justification demonstrating that a given statement must be true. The purposes of this paper are to describe some of the different types of reasoning and problem-solving processes used by undergraduates to construct proofs in their university mathematics courses, and to consider the relationship between the reasoning that students use when constructing a proof and what they have the opportunity to learn from their proving experience.
Large rectifier station practice: Station design

THE use of the mercury-arc rectifier to supply large amounts of direct current required in electrochemical and electrometallurgical industries has received considerable impetus in the last several decades by many new installations by large companies. Operating experience and installation details as described by representatives of four companies provide interesting material for comparison.
Consequences of mite feeding injury to beans on the fecundity and survivorship of the two-spotted spider mite (Acari: Tetranychidae)

Fecundity and survival of the two-spotted spider mite,Tetranychus urticae Koch, were examined on bean (Phaseolus vulgaris L.) plants that had been subjected to mite feeding injury in the laboratory. Different numbers ofT. urticae were restricted on the first two leaves of young bean plants, and spider-mite fecundity and survivorship was assayed on the third leaf. Each plant received four recently enclosed females, one female from each of four mite lineages. Using changes in the ratio of root mass to shoot mass of bean plants as a continuous measure of plant stress from spider-mite feeding, fecundity was positively related to stress for three out of four experiments. In two out of four experiments, survival of females was also positively related to stress, but reached an asymptote at slight or moderate stress levels. No evidence for induced resistance in beans was found. Mite lineage and the interaction between lineage and stress affected female survival but not fecundity. The implications of these results for understanding spider-mite outbreaks are discussed.
Long-term assessment of right ventricular diastolic filling in patients with pulmonic valve stenosis successfully treated in childhood.

Abstract Patients with severe pulmonic stenosis (PS) have right ventricular (RV) diastolic filling abnormalities detectable by tricuspid valve pulsed Doppler examination. To determine if these abnormalities persist long term after successful therapy of PS, 19 patients were examined 8 ± 3 years after PS therapy. At the time of follow-up Doppler examination, the PS gradient was 15 ± 8 mm Hg. From the tricuspid valve inflow Doppler study, the following measurements were obtained at peak inspiration: peak velocities at rapid filling (peak E) and during atrial contraction (peak A), ratio of peak E to peak A velocities, RV peak filling rate normalized for stroke volume, deceleration time, the fraction of filling in the first 0.33 of diastole as well as under the E and A waves, and the ratio of E to A area. Data from PS follow-up patients were compared with our previously reported data from 12 age-related control subjects and 14 untreated patients with PS. Patients with PS who were followed up had higher peak E velocity (0.75 ± 0.14 vs 0.59 ± 0.21 m/s), lower peak A velocity (0.47 ± 0.09 vs 0.64 ± 0.28 m/s), higher E A velocity ratio (1.65 ± 0.33 vs 1.11 ± 0.52), higher 0.33 area fraction (0.52 ± 0.08 vs 0.34 ± 0.14), lower A area fraction (0.29 ± 0.06 vs 0.45 ± 0.21) and higher E A area ratio (2.48 ± 0.82 vs 1.73 ± 1.05) than PS patients without treatment (p E A area ratio that was slightly lower (2.48 ± 0.82 vs 3.50 ± 1.25) (p
Evaluation of the relationship between elevated vancomycin trough concentrations and increased efficacy and/or toxicity

Isolation of Staphylococcus aureus with minimum inhibitory concentrations, 1 to 2 mg/L, suggests increasing vancomycin trough ranges, from 10 to 20 mg/L or even higher. Vancomycin troughs from 604 treatment courses from 560 patients with suspected or actual Gram-positive infection were analyzed with focus on potential toxicity/efficacy. Trough concentrations were required to be drawn within 15 to 45 minutes before the administration of at least the third vancomycin dose. Patients were retrospectively evaluated for their total daily dose and milligrams per kilograms per vancomycin dose. Data on the duration of vancomycin therapy, days to a normal temperature, and white blood cells were obtained. Data were stratified by trough concentration as 10 mg/L to determine whether there was any relationship between response and trough concentration. Demographic data were obtained in 560 patients with 604 vancomycin treatment courses. For 361 patients with 379 separate treatment courses of vancomycin therapy no other nephrotoxic antimicrobial agent had been used. The greatest risk of vancomycin nephrotoxicity correlated with the duration of treatment. Using the log time to normal temperature, white blood cell count, heart rate, outcome from vancomycin therapy was assessed and no relationship could be demonstrated for the three vancomycin trough strata using analysis of variance (F .05). These data indicate that vancomycin trough elevation may not guarantee treatment success and that there may be no real benefit from higher vancomycin trough concentrations in thermal injury patients with burns <20% TBSA.
Transform methods for the hypergeometric distribution

Two new methods for computing with hypergeometric distributions on lattice points are presented. One uses Fourier analysis, and the other uses Grobner bases in the Weyl algebra. Both are very general and apply to log-linear models that are graphical or non-graphical.
Assuring robustness to noise in optimal quantum control experiments

Closed-loop optimal quantum control experiments operate in the inherent presence of laser noise. In many applications, attaining high quality results [i.e., a high signal-to-noise (S/N) ratio for the optimized objective] is as important as producing a high control yield. Enhancement of the S/N ratio will typically be in competition with the mean signal, however, the latter competition can be balanced by biasing the optimization experiments towards higher mean yields while retaining a good S/N ratio. Other strategies can also direct the optimization to reduce the standard deviation of the statistical signal distribution. The ability to enhance the S/N ratio through an optimized choice of the control is demonstrated for two condensed phase model systems: second harmonic generation in a nonlinear optical crystal and stimulated emission pumping in a dye solution.
Bilingual education policy as political spectacle: educating Latino immigrant youth in New York City

Abstract To examine the ways in which high schools in New York City attend to second language acquisition is to consider everyday actions in schools, government dealings, localized policy responses, and disparate discourses on bilingualism. It is to position the circumstances of learning and teaching English in an American high school within the problems encountered and produced when multiple educational policies collide in local settings, such as individual schools. It is also to consider, and then interrogate, the ‘political spectacle’ in which educational actors associated with schools – teachers, counselors, parents, students, community members, activists, and administrators – become dramaturgically cast into political-policy roles as they enact federal, state, and district policies with regard not only to issues of language acquisition and bilingualism but also to increased accountability, mandated high-stakes testing, and other sanctions-driven approaches. Drawing on qualitative research conducted b...
An unusual presentation of pheochromocytoma.

Pheochromocytoma is a catecholamine-producing tumor that is often considered in a differential diagnosis of secondary hypertension but rarely diagnosed. The tumor is composed of chromaffin cells responsible for producing catecholamines. The classic triad (headache, palpitations and diaphoresis) is easily recognized by most clinicians, but catecholamine excess can present in a variety of different contexts. We describe the case of a woman who developed catecholamine excess after receiving glucocorticoids for an allergic reaction, which resulted in non-ketotic lactic acidosis, non-cardiogenic pulmonary edema and progressed into cardiogenic shock and acute renal failure. A summary outlining this patient’s presentation, hospital course and management will be discussed; in addition, to relevant literature supporting the findings, management and teaching points.
Computerized tomographic and magnetic resonance angiography for perforator-based free flaps: technical considerations.

Perforator-based free flaps rely on the appropriate dominant vessel supplying the vascular territory of the flap. Preoperative knowledge of the vascular anatomy can improve outcome and diminish surgical time. Several preoperative imaging techniques exist for surgical planning. Computed tomographic and magnetic resonance angiography are two emerging modalities that provide exceptional anatomic detail. Despite the growing utilization of cross-sectional imaging for preoperative planning, each modality has specific technical considerations that are necessary to consider in order to produce a quality study.
Diffusion in MgO at high pressure: Implications for lower mantle rheology

Theoretical calculations of diffusion in periclase were performed to model the rheological properties of the lower mantle. Gibbs free energy values derived from molecular dynamics simulations using a non-empirical interatomic potential to accurately predict diffusion in MgO at zero pressure. Diffusion coefficients were computed for pressures and temperatures up to 140 GPa and 5000 K. We find that Mg vacancies required for diffusive transport are likely extrinsic (due to impurities), and the resulting O vacancies would then be too few to support bulk O transport. Estimates of viscosity from these results are consistent with those inferred for the lower mantle from geophysical observations if grain boundary diffusion is responsible for O transport.
The relationship between congressional spending and tenure with an application to term limits

Whether term limits would increase or decrease federal spending depends on the reason for the causal relationship between tenure and spending. We investigate this subject by empirically studying congressional spending and tenure for all United States House and Senate members who entered Congress between the 94th and 102nd Congresses (1975–1992). As our measure of congressional spending we use the National Taxpayers Union's Congressional Spending Scores. Our study finds that a statistically significant relationship exists between congressional spending and tenure for some groups of congressmen. We then test three hypotheses relating tenure and spending. No single hypothesis is consistent with all of our empirical results. Nevertheless, the small sizes of the empirical effects estimated in this study suggest that term limits would have an inconsequential impact on the level of federal spending – at least via the “moral hazard” mechanisms described in this paper.
Optically mapping the electronic structure of coupled quantum dots

Arrays of quantum dots can be useful for building ‘artificial molecules’, and potentially as elements of quantum information networks. But in practice, no two dots are the same. An optical technique provides the means for in situ characterization of individual dots, and their collective properties.
Bayesian analysis for a stress‐strength system under noninformative priors

Noninformative priors are used for estimating the reliability of a stress-strength system. Several reference priors (cf. Berger and Bernardo 1989, 1992) are derived. A class of priors is found by matching the coverage probabilities of one-sided Bayesian credible intervals with the corresponding frequentist coverage probabilities. It turns out that none of the reference priors is a matching prior. Sufficient conditions for propriety of posteriors under reference priors and matching priors are provided. A simple matching prior is compared with three reference priors when sample sizes are small. The study shows that the matching prior performs better than Jeffreys's prior and reference priors in meeting the target coverage probabilities. Nous utilisons des a priori non-informatifs pour estimer la fiabilite d'un systeme stress-puissance. Nous derivons plusieurs a priori de reference (cf. Berger et Bernardo, 1989, 1992). Nous trouvons une classe d'a priori en appariant les probabilites de couverture d'intervalles credibles bayesiennes unilaterales avec les probabilites de couverture frequentistes correspondantes. II appert qu'aucun des a priori de reference est un a priori apparie. Nous fournissons les conditions suffisantes pour la propriete des a posteriori sous a priori de reference et a priori apparies. Nous comparons un a priori apparie simple a trois a priori de reference lorsque les tailles des echantillons sont petites. L'etude demontre que l'a priori apparie obtient une meilleure performance que l'a priori de Jeffrey et les a priori de reference en atteignant les probabilites de couverture cible.