cssi/SciSciGPT-SciSciNet huggingface dataset:
Abnormal Heart Rate Characteristics Predict Urinary Tract Infections in VLBW Infants

Background: Urinary tract infection (UTI) is a common diagnosis in the neonatal intensive care unit (NICU). Approach to diagnosis and management of UTI is controversial in this population, but early detection may lead to improved outcomes. Abnormal heart rate characteristics (HRC) of decreased variability and repetitive transient decelerations are associated with late-onset neonatal sepsis. In an 8-center randomized clinical trial (RCT) of 3,003 VLBW infants, continuous HRC index (HeRO score) monitoring was associated with 22% lower all-cause mortality (Moorman, 2011) and 40% lower septicemia-associated mortality (Fairchild 2013). Urine culture results have …
The effect of institutional distance on international market selection: comparing export to foreign direct investment

The goal of the current paper is to investigate the effect of institutional distance on market expansion. We specifically focus on two dependent variables, export and foreign direct investments (FDIs) from the USA. The research uses a cross-sectional time-series analysis to test the influence of institutional factors on exports and FDI. Dimensions of the institutional environment have an effect on export and FDI activity between two countries. The regulative, normative, and cultural dimensions of the institutional environment vary in importance across the two modes of entry. Of the three, culture turns out to be the most significant. Our framework allows companies to classify markets with regards to these macro variables and then investigate international expansion opportunities.
Novel Treatment-Refractory Preschool Wheeze Phenotypes Identified by Cluster Analysis of Lung Lavage Constituents.

Background Preschool children with treatment-refractory wheeze often require unscheduled acute care. Current guidelines advise treatment of persistent wheeze with inhaled corticosteroids. Alternative treatments targeting structural abnormalities and specific inflammatory patterns could be more effective. Objective To apply unsupervised analysis of lung lavage (bronchoalveolar lavage [BAL]) variables to identify clusters of preschool children with treatment-refractory wheeze. Methods A total of 155 children 6 years or younger underwent bronchoscopy with BAL for evaluation of airway structure, inflammatory markers, and pathogens. Variables were screened with factor analysis and sorted into clusters by Ward's method, and membership was confirmed by discriminant analysis. Results The model was repeatable in a 48-case validation sample and accurately classified 86% of cases. Cluster 1 (n = 60) had early-onset wheeze, 85% with structural abnormalities, mostly tracheamalacia, with low total IgE and agranulocytic BAL. Cluster 2 (n = 42) had later-onset wheeze, the highest prevalence of gastroesophageal reflux, little atopy, and two-third had increased BAL lipid-laden macrophages. Cluster 3 (n = 46) had mid-onset wheeze, low total IgE, and two-third had BAL viral transcripts, predominately human rhinovirus, with BAL neutrophilia. Cluster 4 (n = 7) was older, with high total IgE, blood eosinophilia, and mixed BAL eosinophils and neutrophils. Conclusions Preschool children with recurrent wheeze refractory to inhaled corticosteroid treatment include 4 clusters: airway malacia, gastroesophageal reflux, indolent human rhinovirus bronchoalveolitis, and type-2high inflammation. The results support the risk and cost of invasive bronchoscopy to diagnose causes of treatment-refractory wheeze and develop novel therapies targeting airway malacia, human rhinovirus infection, and BAL neutrophilia in preschool children.
Making the Grade during Pandemic: Early-stage and Late-stage Provisional Institutions

This is an article that draws on the institutional work literature about provisional institutions. To date, nearly every U.S. sector has been impacted by COVID-19. To sustain their core missions, h...
2020 U.S. Presidential Election: Analysis of Female and Male Users on Twitter.

Social media is commonly used by the public during election campaigns to express their opinions regarding different issues. Among various social media channels, Twitter provides an efficient platform for researchers and politicians to explore public opinion regarding a wide range of topics such as economy and foreign policy. Current literature mainly focuses on analyzing the content of tweets without considering the gender of users. This research collects and analyzes a large number of tweets and uses computational, human coding, and statistical analyses to identify topics in more than 300,000 tweets posted during the 2020 U.S. presidential election and to compare female and male users regarding the average weight of the topics. Our findings are based upon a wide range of topics, such as tax, climate change, and the COVID-19 pandemic. Out of the topics, there exists a significant difference between female and male users for more than 70% of topics. Our research approach can inform studies in the areas of informatics, politics, and communication, and it can be used by political campaigns to obtain a gender-based understanding of public opinion.
Extending EO and the Role of the Top Management Team

This chapter centers on the top management team, which is an under-explored context in EO research. I begin the chapter by tackling the question if the firm wants to maximize its EO, should it universally have entrepreneurially minded senior executives; that is, to be an entrepreneurial firm, its senior leaders should themselves be inclined toward entrepreneurship. I also briefly consider the perspective sometimes raised in the EO literature that a firm’s performance yield from EO may be a function of counterbalance among the executive team—a CEO with a high tolerance for entrepreneurial risk may benefit from a chief operating officer with a modest risk tolerance. I then explore differences across senior executive roles, and how those roles may enable or constrain the firm’s EO. I then investigate the role of performance evaluations, and how the firm’s appraisal structure may enable or constrain EO. Lastly, I consider the role of middle management in the firm’s EO, specifically through the lens of strategic execution.
Gardner-associated fibroma presenting as an unusual floor of mouth mass in a child:

Floor of mouth lesions in the paediatric population are uncommon. The spectrum of pathology that afflicts the floor of mouth spans inflammatory conditions, developmental anomalies, vascular malform...
Challenges to the Self

On her way to recovery after a long illness, Caroline no longer felt like the attractive, sophisticated woman she had been. “I feel like a doddering old lady,” she cried woefully. “I have no energy; I feel ugly, gnarled—like one of those old women sitting on a veranda, rocking in her chair, as if life has passed me by—I can’t fight anymore.” Trying to regain her old self seemed like too much of an effort, and for that matter she wasn’t sure that she wanted to be that person anymore.
Variation in copepod species assemblage distributions: The utility of the log-normal approach

Abstract Pelagic copepod species distributions were found to vary in relation to an environmental gradient. As suggested by Gray, systematic changes were noted in the skewness of the log-normal. However, no systematic changes in the standard of deviation of the log-normal were noted. The data indicate that such assemblages ill-fit Preston's ‘canonical’ expectation. Further, analysis of changes in the evenness function yielded similar conclusions.
Atomic-resolution single-spin magnetic resonance detection concept based on tunneling force microscopy

A study of a force detected single-spin magnetic resonance measurement concept with atomic spatial resolution is presented. The method is based upon electrostatic force detection of spin-selection rule controlled single-electron tunneling between two electrically isolated paramagnetic states. Single-spin magnetic resonance detection is possible by measuring the force detected tunneling charge noise on and off spin resonance. Simulation results of this charge noise, based upon physical models of the tunneling and spin physics, are directly compared to measured atomic force microscopy system noise. The results show that the approach could provide single-spin measurement of electrically isolated qubit states with atomic spatial resolution at room temperature.
Comparison of High Performance Liquid Chromatography and Enzymatic Method for the Measurement of Lactose in Milk

A high performance liquid chromatographic (HPLC) procedure was compared with an enzymatic method for the measurement of lactose in milk. A new rapid HPLC sample preparation technique was used for precipitating milk proteins with 2-propanol. Results indicated that lactose detected in milk (expressed as percentage) was consistently lower with the enzymatic method than the HPLC procedure. Mean difference between the two methods was 0.15% with a range of 0.04 to 0.51. Coefficient of variability for the HPLC and enzymatic methods were 1.02 and 2.75, respectively. Recovery of added lactose in milk by HPLC was 100.3% for whole milk, 97.1% for low fat milk, and 99.5% for skim milk.
Acute transverse myelitis and silent infection with Mycoplasma pneumoniae

Mycoplasma pneumoniae is a bacterium which frequently causes respiratory symptoms but may present neurological complications. We report two cases of pediatric patients with acute transverse myelitis as a complication of silent infection with M. pneumoniae. To our knowledge, these are two unique cases in which respiratory symptoms did not appear prior to onset of neurological complications. We believe that clinicians may need to reevaluate the existing diagnostic protocol of acute transverse myelitis and routinely consider M. pneumoniae as a potential etiology.
Interactive effects of pH and leaf litter on a shredder, the scirtid beetle, Helodes pulchella, inhabiting tree‐holes

1. Scirtid beetles (Coleoptera: Scirtidae) are common inhabitants of water-filled treeholes and interact with other detritivores in a processing chain commensalism. The strength of the commensalism is determined by resource quantity and the organisms involved have different tolerances to low pH. To determine the effects and interactions of resource quantity and pH on one of these leaf-shredding scirtid beetles, Helodes pulchella (Guerin), leaf litter and pH were varied independently in experimental microcosms which mimic treehole habitats. 2. Helodes pulchella growth was affected by both resources and pH in two similar experiments conducted in different years. Scirtid larvae grew more slowly in low resource treatments and also grew more slowly in low pH treatments. Scirtid survival was not affected by pH, but was lower in high resource microcosms in the 1997 experiment. Consumption of leaf litter was much higher in high resource microcosms, even though not all leaf litter was consumed in low leaf litter treatments. 3. Thus, water chemistry and leaf litter quantity could have strong effects on resource availability through effects on these beetle facilitators, in turn affecting other insects living in these detritus-based communities.
Reactive oxygen species contribute to arsenic-induced EZH2 phosphorylation in human bronchial epithelial cells and lung cancer cells

Our previous studies suggested that arsenic is able to induce serine 21 phosphorylation of the EZH2 protein through activation of JNK, STAT3, and Akt signaling pathways in the bronchial epithelial cell line, BEAS-2B. In the present report, we further demonstrated that reactive oxygen species (ROS) were involved in the arsenic-induced protein kinase activation that leads to EZH2 phosphorylation. Several lines of evidence supported this notion. First, the pretreatment of the cells with N-acetyl-l-cysteine (NAC), a potent antioxidant, abolishes arsenic-induced EZH2 phosphorylation along with the inhibition of JNK, STAT3, and Akt. Second, H2O2, the most important form of ROS in the cells in response to extracellular stress signals, can induce phosphorylation of the EZH2 protein and the activation of JNK, STAT3, and Akt. By ectopic expression of the myc-tagged EZH2, we additionally identified direct interaction and phosphorylation of the EZH2 protein by Akt in response to arsenic and H2O2. Furthermore, both arsenic and H2O2 were able to induce the translocation of ectopically expressed or endogenous EZH2 from nucleus to cytoplasm. In summary, the data presented in this report indicate that oxidative stress due to ROS generation plays an important role in the arsenic-induced EZH2 phosphorylation.
Pressurized Xenon-Filled Multiwire Proportional Chamber for Radionuclide Imaging

A pressurized multiwire proportional chamber radionuclide imaging system has been constructed which has operated at pressures of up to 11 atmospheres absolute using a xenon-methane gas mix. The experimental detector has an active imaging area of 25 sq. cm. and an effective depth of 11 cm. An all digital readout system has been constructed with an intrinsic resolution of 1.3 mm FWHM. The FWHM has been measured for various radionuclides: iodine-125 (28 keV), 1.3 mm; thallium - 201 (75 keV), 2 mm; technetium-99 m (140 keV), 3 mm. Our primary goal has been the investigation of properties of such detectors that offer advantages over conventional gamma cameras, including high data rate and improved spatial resolution, particularly for isotopes with photon energies below 100 keV. We have fabricated a gas purification system which permits long term operation of the system without degradation and have investigated construction techniques to produce reliable devices which could be used in a hospital environment.
Hemoglobins in Macaca speciosa: quantitative differences.

Abstract The Macaca speciosa, which possess two hemoglobins in unequal concentrations, were used to study factors responsible for quantitative differences in the production of proteins. Relative rates of synthesis of the two hemoglobins were determined in both immature and mature synthesizing systems by measuring the in vitro incorporation of radioactive leucine into hemoglobin by whole cells. Evidence of hemoglobin destruction was also sought. It was concluded that the unequal proportions of these hemoglobins in erythrocytes were not caused by differences in rates of synthesis. Attempts to detect additional hemoglobins, structurally different but electrophoretically equivalent, were unsuccessful.
Astronomy: Galaxy sets distance mark.

A galaxy has smashed the record for the most distant object ever observed. The object sheds light on the nature of the sources that stripped electrons from hydrogen atoms during the reionization epoch. See Letter p.940 Until now, the most distant spectroscopically confirmed galaxies known in the Universe were at redshifts z ≈ 8.2 and z ≈ 6.96. Lehnert et al. now report that UDFy-38135539 is at a redshift of z = 8.6. The galaxy was first identified as a candidate z ≈ 8.6 object in deep Wide Field Camera 3 observations of the Hubble Ultra Deep Field, and the discovery in ground-based observations that it is emitting Lyman-α photons provides confirmation. This single source is unlikely to provide enough photons to ionize the volume necessary for the emission line to escape, requiring a significant contribution from other, probably fainter galaxies nearby.
Glycogen synthase kinase-3 (GSK3): Regulation, actions, and diseases

Glycogen synthase kinase-3 (GSK3) may be the busiest kinase in most cells, with over 100 known substrates to deal with. How does GSK3 maintain control to selectively phosphorylate each substrate, and why was it evolutionarily favorable for GSK3 to assume such a large responsibility? GSK3 must be particularly adaptable for incorporating new substrates into its repertoire, and we discuss the distinct properties of GSK3 that may contribute to its capacity to fulfill its roles in multiple signaling pathways. The mechanisms regulating GSK3 (predominantly post-translational modifications, substrate priming, cellular trafficking, protein complexes) have been reviewed previously, so here we focus on newly identified complexities in these mechanisms, how each of these regulatory mechanism contributes to the ability of GSK3 to select which substrates to phosphorylate, and how these mechanisms may have contributed to its adaptability as new substrates evolved. The current understanding of the mechanisms regulating GSK3 is reviewed, as are emerging topics in the actions of GSK3, particularly its interactions with receptors and receptor-coupled signal transduction events, and differential actions and regulation of the two GSK3 isoforms, GSK3α and GSK3β. Another remarkable characteristic of GSK3 is its involvement in many prevalent disorders, including psychiatric and neurological diseases, inflammatory diseases, cancer, and others. We address the feasibility of targeting GSK3 therapeutically, and provide an update of its involvement in the etiology and treatment of several disorders.
Deep Infrared Imaging of the Microquasars 1E 1740-2942 and GRS 1758-258

We present deep infrared (2.2 μm) imaging of the Galactic microquasars 1E 1740-2942 and GRS 1758-258 using the Keck I 10 m telescope in 1998 June. The observations were taken under excellent seeing conditions (~045 full width at half-maximum), making them exceptionally deep for these crowded fields. We used the USNO-A2.0 catalog to astrometrically calibrate the infrared images (along with an optical CCD image in the case of GRS 1758-258), providing independent frame ties to the known radio positions of the objects. For 1E 1740-2942, we confirm potential candidates for the microquasar previously identified by Marti et al. and show that none of the objects near the microquasar have varied significantly from 1998 to 1999. For GRS 1758-258, our astrometry indicates a position shifted from previous reports of candidates for the microquasar. We find no candidates inside our 90% confidence radius to a 2 σ limiting magnitude of Ks = 20.3 mag. We discuss the implications of these results for the nature of the microquasar binary systems.
Hybrid simulations of the saturated Farley‐Buneman instability in the ionosphere

Numerical simulations of the Farley-Buneman instability in 2-1/2 dimensions using particle ions and fluid electrons show the growth, saturation and nonlinear behavior of two-stream waves. This hybrid technique models the saturated state of the instability for a much longer period of time than the pure particle codes that preceded it. While focusing principally on modeling the topside E region equatorial electrojet, many of these results apply to the auroral two-stream instability as well. The following features are seen in all our hybrid simulations: (1) wave growth at an angle offset from the electron drift direction where the angle depends on the strength of the driving electric field, (2) nonlinear coupling to waves traveling perpendicular to the propagation direction of the principal two-stream waves, (3) a saturated wave phase velocity at or above the sound speed but well below the velocity predicted by linear theory and (4) phase velocities which remain almost constant as a simulated radar sweeps from a horizontal direction to nearly vertical. The nonlinear electron motion dominates the behavior of these waves. Further, these simulations indicate that ion kinetic effects are not essential for the saturation of the instability and that electron temperature effects have a minor impact on the final saturated state.
Diffusional deposition of airborne particles in curved bronchial airways

Abstract The diffusional deposition in a curved tube is investigated theoretically and the results show good agreement with experimental data obtained by Bell (1974). It is shown that the deposition flux per unit tube length based on heat transfer analogy yields values higher than both Bell's experimental data and our calculated values. The increase in diffusional particle deposition in the human respiratory airways due to secondary swirling motion in a curved tube is also discussed.
Effect of Temperature and an Ion‐Exchange Resin on Cation Diffusion through Silicone Polymer Tubing

Abstract Permeation of cations through silicone rubber tubing was measured, and the effect of an ion‐exchange resin on the cation diffusion was determined. Silicone rubber has been used as a biomedical polymer and shows a very low solubility to ionizable species. Correlations between the calculated diffusion coefficients, with and without the resin, depended on the charge and number of waters of hydration for each cation. These increases ranged from 1.11 for potassium to 3.06 for iron, multiplied by the diffusion coefficient as a result of the resin. Solubilities of each cation in the polymer were temperature dependent. Activation energies were calculated for each cation by measuring the increased permeation with increasing temperature, with and without the resin. Decreasing magnitudes of activation energies ranged from 0.9) for sodium to 0.57 for iron when the resin was present. Correlations were established between the measured activation energies and reported free energy change for the hydration of each cation.
A 10-year climatology of tropical radiative heating and its vertical structure from TRMM observations.

Abstract This paper outlines recent advances in estimating atmospheric radiative heating rate profiles from the sensors aboard the Tropical Rainfall Measuring Mission (TRMM). The approach employs a deterministic framework in which four distinct retrievals of clouds, precipitation, and other atmospheric and surface properties are combined to form input to a broadband radiative transfer model that simulates profiles of upwelling and downwelling longwave and shortwave radiative fluxes in the atmosphere. Monthly, 5° top of the atmosphere outgoing longwave and shortwave flux estimates agree with corresponding observations from the Clouds and the Earth’s Radiant Energy System (CERES) to within 7 W m−2 and 3%, respectively, suggesting that the resulting products can be thought of as extending the eight-month CERES dataset to cover the full lifetime of TRMM. The analysis of a decade of TRMM data provides a baseline climatology of the vertical structure of atmospheric radiative heating in today’s climate and an es...
Epigenetic genome control by heterochromatin and RNAi machinery

RNAi is a conserved mechanism in which small interfering RNAs (siRNAs) guide the degradation of cognate RNAs, but also promote heterochromatin assembly at repetitive DNA elements such as centromeric repeats. However, the full extent of RNAi functions and its endogenous targets have not been explored. We show that in the fission yeast Schizosaccharomyces pombe, RNAi and heterochromatin factors cooperate to silence diverse loci, including sexual differentiation genes, genes encoding transmembrane proteins, and retrotransposons that are also targeted by the exosome RNA degradation machinery. In the absence of the exosome, transcripts are processed preferentially by the RNAi, revealing siRNA clusters and corresponding increase in heterochromatin modifications across large domains containing genes and retrotransposons. Interestingly, the generation of siRNA clusters and heterochromatin assembly by RNAi is triggered by a mechanism involving the canonical poly(A) polymerase Pla1 and an associated RNA surveillance factor Red1, which also activate the exosome. More importantly, siRNA production and heterochromatin modifications at these target loci are regulated by environmental growth conditions, and by developmental signals that induce gene expression during sexual differentiation. These analyses uncover interplay between RNAi and the exosome that is conserved in higher eukaryotes, and show that differentiation signals modulate RNAi silencing to regulate developmental genes.
Aging and infection reduce expression of specific brain-derived neurotrophic factor mRNAs in hippocampus.

Abstract Aging increases the likelihood of cognitive decline after negative life events such as infection or injury. We have modeled this increased vulnerability in aged (24-month-old), but otherwise unimpaired F344xBN rats. In these animals, but not in younger (3-month-old) counterparts, a single intraperitoneal injection of E. coli leads to specific deficits in long-term memory and long-lasting synaptic plasticity in hippocampal area CA1—processes strongly dependent on brain-derived neurotrophic factor (BDNF). Here we have investigated the effects of age and infection on basal and fear-conditioning-stimulated expression of Bdnf in hippocampus. We performed in situ hybridization with 6 probes recognizing: total (pan-)BDNF mRNA, the 4 predominant 5′ exon-specific transcripts (I, II, IV, and VI), and BDNF mRNAs with a long 3′ untranslated region (3′ UTR). In CA1, aging reduced basal levels and fear-conditioning-induced expression of total BDNF mRNA, exon IV-specific transcripts, and transcripts with long 3′ UTRs; effects of infection were similar and sometimes compounded the effects of aging. In CA3, aging reduced all of the transcripts to some degree; infection had no effect. Effects in dentate were minimal. Northern blot analysis confirmed an aging-associated loss of total BDNF mRNA in areas CA1 and CA3, and revealed a parallel, preferential loss of BDNF mRNA transcripts with long 3′ UTRs.
Observed wurtzite derivatives and related dipolar tetrahedral structures

Abstract Eight lower-symmetry ordered derivatives of the wurtzite type and an additional six related dipolar tetrahedral structure types were observed. All these structures are based on hexagonal closest packing of anions. Their mutual symmetry relationships can be summarized in a Barnighausen diagram. Dipolar tetrahedral structures are characterized by centrosymmetric space groups, thus resulting in a dipolar distribution of the coordination tetrahedra. Dipolar tetrahedral structures often exhibit disorder and random statistical occupations and several good ionic conductors are found among them. The wurtzite-type derivatives are characterized by polar space groups and all coordination tetrahedra in them are pointing in the same direction. Some simple, geometrically possible wurtzite derivatives have never been observed. Their absence can be rationalized on the basis of a poor geometrical fit between tetrahedral chains as demonstrated by computer simulations of their hypothetical structures. The ratio ϵ (quotient of the thickness of one hexagonal layer in [001] over one measure of the mean diameter of one atom within this layer) is useful for ordering the wurtzite derivatives on the basis of their chemical composition, since ϵ increases from the oxides, over the nitrides to the sulfides. The ϵ ratio also distinguishes clearly between the oxidic wurtzite types (0.79) and the tetrahedral rutile types of β-BeO derivatives (0.86), while the dipolar tetrahedral types have ϵ values around 0.82, that is, close to the value expected for hexagonal closest packing.
Obstructive sleep apnea associated with erectile dysfunction and cardiovascular disease.

We appreciate Dr Edmond's comments regarding previously observed associations between OSA and ED and CVD. However, previous associations between OSA and ED are not completely consistent.1,2 Additionally, in the Olmsted County Study of Urinary Symptoms and Health Status among Men, heavy snoring was associated with decreased sexual satisfaction but not with ED, ejaculatory dysfunction, or decreased sexual drive.3 These results suggest that physiologic sexual dysfunction may be limited only to men with severe cases of OSA.
Reaching VUV transitions with multiphoton processes

A review of the historical development of multiphoton processes with emphasis on high degrees of excitation is given. The present understanding of the mechanisms involved will be discussed along with some special effects due to multiphoton transitions. Finally, an account of more recent work concerning autoionizing resonances and their behavior under the influence of strong fields will be given.
Low-dose aldosterone blockade as a new treatment paradigm for controlling resistant hypertension.

Treatment of resistant hypertension requires confirmation of true resistance, diagnosis and treatment of secondary causes of hypertension, adoption of appropriate lifestyle modifications, and effective use of multidrug antihypertensive regimens. Excessive volume retention often underlies resistant hypertension, so diuretics are generally necessary to achieve blood pressure (BP) goals. Although treatment regimens consisting of 3 or more agents have not been systematically evaluated, the author has found a triple regimen consisting of a thiazide diuretic, a calcium channel blocker, and an angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) to be generally effective and well tolerated. Although hydrochlorothiazide is more widely used, chlorthalidone provides better BP reduction and should be preferentially used in patients with resistant hypertension, particularly if the patient remains uncontrolled on hydrochlorothiazide. Recent studies have demonstrated that low doses of aldosterone antagonists, when added to multi-drug regimens that include a thiazide diuretic and an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, provide significant additional BP reduction, seemingly exceeding what would be expected with addition of alternative classes of agents. The degree of BP reduction induced by aldosterone blockade has been similar in patients with and without evidence of aldosterone excess. Aldosterone antagonists are generally safe and well tolerated. The most common adverse effect of low-dose spironolactone has been breast tenderness, occurring in about 10% of men. Hyperkalemia is uncommon, but can occur, necessitating biochemical monitoring. Risk of hyperkalemia is increased in patients with chronic kidney disease or diabetes, elderly patients, and patients already receiving an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker.
Continued-factorization method for optical dispersion*

A set of continually factorized uniformly convergent series is introduced for optical refractivities. Upper and lower bounds on the refractivities are obtained by truncating two such adjacent series, which alternately converge from above and below, after finite numbers of terms. The extent to which the present method complements the Pade method for extrapolating the refractive index from infrared and visible to ultraviolet frequencies is demonstrated by calculations on heavy inert gases. With exactly the same original data, the present method sometimes helps to reduce the Pade bounds to one third. The present method also complements Wolfsohn’s method in obtaining bounded estimates of oscillator strengths from refractivity measurements. This is illustrated in the case of argon, for which the oscillator strengths of two close lines are separately determined. In the case of atomic hydrogen, the results of the present method for oscillator strengths and the refractivity, below as well as above the first resonance line, are compared with exact values. Finally, as an illustrative example of estimating the refractivity at frequencies above the first resonance line, we extend a Sellmeier dispersion equation for argon in the normal-dispersion region to frequencies between the first and third excitation levels.
Hepatic protein kinase C is not activated despite high intracellular 1,2-sn-diacylglycerol in obese Zucker rats

Abstract High intracellular 1,2,-sn-diacylglycerol (DAG) usually activates protein kinase C (PKC). In choline-deficient Fischer 344 rats, we previously showed that fatty liver was associated with elevated hepatic DAG and sustained activation of PKC. Steatosis is a sequelae of many liver toxins, and we wanted to determine whether fatty liver is always associated with accumulation of DAG with activation of PKC. Obese Zucker rats had 11-fold more triacylglycerol in their livers and 2-fold more DAG in their hepatic plasma membrane than did lean control Zucker rats. However, this increased diacylglycerol was not associated with translocation or activation of PKC in hepatic plasma membrane (activity in obese rats was 897 pmol/mg protein×min−1 vs. 780 pmol/mg protein×min−1 in lean rats). No differences in PKC isoform expression were detected between obese and lean rats. In additional studies, we found that choline deficiency in the Zucker rat did not result in activation of PKC in liver, unlike our earlier observations in the choline deficient Fischer rat. This dissociation between fatty liver, DAG accumulation and PKC activation in Zucker rats supports previous reports of abnormalities in PKC signaling in this strain of rats.
Endogenous Technological Progress and the Malthusian Trap: Could Simon and Boserup Have Saved Easter Island?

One solution typically suggested for the Malthusian Trap involves technological progress. Using Easter Island as a natural experiment, we ask what could have happened had the island’s technology progressed over time? As argued by Julian Simon and Ester Boserup, we assume that technological progress rises with resource scarcity and population size. The analysis employs model building and simulations. The model includes a composite manufactured good and a composite harvested renewable resource. The resource’s carrying capacity, intrinsic growth rate, and harvesting productivity are subject to endogenous technological progress. The model yields a system of five simultaneous, nonlinear differential equations, which is parameterized for Easter Island and simulated. In all cases, the population, resource and social welfare trajectories exhibit a significant boom-bust nature. The forces envisioned by Simon and Boserup then, do not save our (hypothetical) Easter Island. The relevance of these findings to contemporary less developed societies is evaluated.
Cysteine string proteins and presynaptic function.

Abstract A brief review is presented of investigations of a novel family of synaptic vesicle proteins, the cysteine string proteins (csps). Studies of csp mutants in Drosophila reveal that csps are crucial components of the excitation-secretion machinery at nerve terminals. Current data cannot distinguish between a primary role of csps in modulating calcium ion influx at the nerve terminal versus a more-direct role in the exocytotic cascade. In this context, the remarkable post-translational modification of csps, namely the fatty acylation of as many as 12 of the 13 cysteine residues of the Torpedo protein, suggests that csps may participate more directly in the process of membrane fusion that underlies exocytosis. This would be achieved by using the fatty acyl chains of the csps as templates for ‘lipid flow’ that would allow the fusion of vesicular and plasma membranes. These hypotheses provide a useful framework for empirical tests of the role of csps in nerve terminal function.
Interdisciplinary research is key to understanding sex differences: report from the Society for Women's Health Research Meeting on understanding the biology of sex differences.

Progress in sex-based biology, the study of biological and behavioral differences between males and females, and the impact of those differences on health and disease will require collaboration across research disciplines and medical specialties and among all research approaches, from molecular biology to epidemiology. The importance of sex-based biology to healthcare necessitates a bench-to-bedside approach that is built on integration of research findings from studies at the cellular level, in animals, and in human subjects. Barriers to interdisciplinary collaborations are being addressed in a variety of ways by public and private funders. The J.D. and C.T. MacArthur Foundation supports interdisciplinary research networks that address broad questions in health and behavior. The National Institute of Mental Health supports cross-disciplinary research networks investigating the hypothalamic-pituitary-adrenal network. The National Institute of Child Health and Human Development offers grants for Building I...
Refutational theorem proving using term-rewriting systems

Abstract In this paper we propose a new approach to theorem proving in first-order logic based on the term-rewriting method. First for propositional calculus, we introduce a canonical term-rewriting system for Boolean algebra. This system enables us to transform the first-order predicate calculus into a form of equational logic, and to develop several complete strategies (both clausal and nonclausal) for first-order theories based on the Knuth-Bendix Completion Procedure. More importantly, our strategies can deal with predicate logic and built-in (equational) theories in a uniform and effective way. We also describe an implementation and comparisons with some other first-order theorem-proving methods.
PIV measurements of flow in and around scour holes

Two sets of experiments related to the scour of cohesionless sediment by planar turbulent jets are presented and discussed. The first set of experiments measures the growth of the scour hole and downstream dune as a function of time. Measurements reveal a bedform that is nearly self-similar and whose growth in time is governed by a power-law relationship. The bedform is well represented by three linear segments with slopes near the angle of repose of the sediment. The second set of experiments uses Particle Image Velocimetry to characterize the mean velocity field in the scour hole and above the dune. For this set of experiments, a series of successively larger roughened fixed-bed models was used in place of the mobile bed. The measurements reveal the presence of strong recirculation in the hole and an attached wall jet on the main slope. Discussion of the utility of the present fixed-bed measurements in estimating shear stress along the bed and related application to predictive modeling of hydraulic scour is provided. Discussion of the technical challenges of similar mobile-bed measurements is also given.
A retrospective assessment of the flow regulation of the West Salmon River, Newfoundland, Canada

The Upper Salmon Hydroelectric Project in central Newfoundland, Canada, constructed in the early 1980s, affected the hydrology of the West Salmon River, a major spawning and juvenile rearing river for landlocked Atlantic salmon, Salmo salar L., and brook trout, Salvelinus fontinalis (Mitchill). A controlled flow release strategy, based on Tennant’s Montana method, was developed to protect this habitat and prescribed a release of 40% of the mean annual flow (MAF) (2.6 m3 s–1) between 1 June and 30 November and 20% of the MAF (1.3 m3 s–1) from 1 December to 31 May. Studies were conducted to assess the impact of river regulation including: (1) a post-impoundment evaluation of the anticipated geomorphic and sedimentary characteristics; (2) monitoring of juvenile fish populations under regulation; and (3) a retrospective IFIM (instream flow incremental methodology) assessment. Studies provided evidence of the initial stages of river aggradation. Biological monitoring found no apparent effects of sediment deposition on spawning and egg incubation. However, densities of older age classes (parr, 1+ and greater) declined under regulation, possibly related to poor overwintering conditions under the lower winter flow. IFIM study results supported these observations and indicated that the prescribed flow regimen provided habitat conditions that would benefit salmon fry more than older age classes. This retrospective assessment suggested that future proposals for flow regulation in Newfoundland should consider the need for more dynamic flow management as well as to provide overwintering habitat for resident fish. Habitat–hydraulic models are preferred to standard setting approaches owing to more detailed analysis of habitat trade-offs as related to flow regulation.
Biological and molecular characteristics of the premalignant mouse mammary gland

Preneoplastic lesions in murine mammary tumorigenesis have been extensively investigated over the past 50 years. The two general types of lesions that have malignant potential are the alveolar hyperplasias represented by the classical hyperplastic alveolar nodule (HAN) and the ductal hyperplasias (DHs) represented by usual DH and ductal carcinoma in situ (DCIS). The former type of lesion is induced by viral, chemical and hormonal agents; the latter by chemical agents and specific genetic alterations. Individual animal models have been utilized to elucidate the basic biological properties of the lesions and some of the basic molecular alterations. The biological phenotype of the two types of lesions include immortalization and epithelial hyperplasia. The DHs are distinguished from the alveolar hyperplasias by their pattern of epithelial hyperplasia, extent of ovarian hormone dependence, activation of telomerase and presence of aneuploidy. The molecular alterations underlying mammary epithelial hyperplasia are numerous and dependent on the particular animal model. An important issue is how faithfully any of these models mimic human premalignant progression. A minimal set of criteria is proposed that includes morphological progression, hormone dependence and genetic instability. Analogous hyperplasias from several defined genetic models, adequately characterized at the biological and molecular levels, would provide appropriate models for testing chemopreventive agents and for elucidating secondary molecular events causative for malignant behavior.
Spatial Representations of the Sets of Familiar and Unfamiliar Television Programs

Three experiments explored representations of spaces depicted on long-running television shows. The first two experiments tested representations of the space depicted in the show ER, which is filmed on a multiple-view set that allows the action to be viewed from any vantage point. Participants who had not seen the show, as well as those who had seen it frequently, made judgments about relative directions on the ER set. The experienced viewers were unable to perform this task more accurately than novices. In the third experiment, representations of two multiple-view sets (ER and West Wing) were compared with representations of more traditional constrained-view sets in which camera positions are limited to the region behind a “fourth wall.” Results demonstrated that experience watching the constrained-view shows was much more strongly associated with accurate representations than was experience with the multiple-view shows. In addition, a novel view of a constrained set was tested, and experience again did ...
Isolation and characterization of mutations affecting UDPG pyrophosphorylase activity in Dictyostelium discoideum

A procedure for screening large numbers of clones for an enzyme activity was used to isolate mutations which affect UDPG pyrophosphorylase activity (EC 2.7.7.9) in the cellular slime mold Dictyostelium discoideum. Five strains were recovered which have little or no UDPG pyrophosphorylase activity. Ten other strains were found which have significant activity in vivo which is rapidly inactivated upon cell lysis. These strains have permitted us to evaluate the role of UDPG pyrophosphorylase during growth and development. The enzyme affects the growth rate of the cells but is not essential for growth. However, during development the lack of enzyme activity leads to cell death and lysis. Strains which lack UDPG pyrophosphorylase accomplish early developmental events but are unable to culminate. However, certain biochemical and cytological differentiations associated with late stages were observed.
Pediatric intradural extramedullary synovial sarcoma: case report.

OBJECTIVE: The diagnosis of intradural synovial sarcoma has not been previously published. This report provides a summary of the literature on this tumor and on tumors arising in this location, as well as a description of this patient's clinical course. CLINICAL PRESENTATON: An 11-year-old girl presented with back pain and radiculopathy. A magnetic resonance imaging scan of the spine revealed a spinal intradural, extramedullary mass at L2-L4, and four additional nodules of enhancement. INTERVENTION: The mass was nearly totally resected. Radiation and chemotherapy were administered. Intracranial metastases became evident during treatment. The patient died of the disease 14 months after diagnosis. CONCLUSION: The rapid progression of leptomeningeal metastasis despite maximal treatment demonstrates the aggressive nature of the tumor and the need for further study.
Development of catecholaminergic phenotypic characters in the mouse locus coeruleus in vivo and in culture

Abstract While abundant studies have begun to elucidate ontogeny of the peripheral nervous system, molecular mechanisms underlying brain development remain obscure. To approach this problem, we initiated parallel in vivo and in vitro studies of the mouse locus coeruleus (l.c.), a brainstem noradrenergic nucleus. The catecholaminergic enzymes tyrosine hydroxylase (TH) and dopamine-β-hydroxylase (DBH) were used to monitor phenotypic expression and development. TH catalytic activity and immunocytochemical reactivity were initially detectable on gestational Day 13 (E-13) in vivo, and adult levels of activity were approximated by the third postnatal week. Immunotitration studies indicated that the developmental increase was due to accumulation of enzyme molecules and not enzyme activation. The in vivo developmental profile of DBH approximated that of TH. To begin defining regulatory mechanisms, explants of embryonic brainstem were placed in culture. Explantation on E-12, prior to expression of TH or DBH, resulted in the de novo appearance of these phenotypic characters after 4 days. Explantation on E-18, after the enzymes are already expressed, was followed by a striking sixfold rise in TH activity. Immunotitration studies revealed that the increase in TH activity in E-18 cultures was attributable to increased molecule number, reproducing the in vivo results. Moreover, the E-18 explants, cultured for 3 weeks, attained higher plateau levels of TH activity than E-12 cultures, and this difference was due to increased molecule number. Morphometric analysis indicated that 3-week E-12 cultures actually had more l.c. cells than E-18 cultures, indicating that differences in TH were not due to increased cells in the E-18 l.c. Finally, systematic study revealed that the development of TH activity in culture increased progressively from E-11 to E-12 to E-13, suggesting that critical regulatory events occur at this time. Our studies suggest that the l.c. is an excellent model for the study of brain development in vivo and in vitro. Initial phenotypic expression and dramatic development occur in culture in the absence of normal targets, normal afferent innervation and, presumably, normal humoural milieu.
Airborne laser scanning for high-resolution mapping of Antarctica

In order to evaluate the potential of airborne laser scanning for topographic mapping in Antarctica and to establish calibration/validation sites for NASA's Ice, Cloud and land Elevation Satellite (ICESat) altimeter mission, NASA, the U.S. National Science Foundation (NSF), and the U.S. Geological Survey (USGS) joined forces to collect high-resolution airborne laser scanning data. In a two-week campaign during the 2001–2002 austral summer, NASA's Airborne Topographic Mapper (ATM) system was used to collect data over several sites in the McMurdo Sound area of Antarctica (Figure 1a). From the recorded signals, NASA computed laser points and The Ohio State University (OSU) completed the elaborate computation/verification of high-resolution Digital Elevation Models (DEMs) in 2003. This article reports about the DEM generation and some exemplary results from scientists using the geomorphologic information from the DEMs during the 2003–2004 field season.