cssi/SciSciGPT-SciSciNet huggingface dataset:
Electron microscope and optical diffraction studies on isolated cell walls from Chlamydomonas.

THERE are few high resolution electron microscope studies specifically concerned with the architecture of the cell walls of the green alga Chlamydomonas. Sager and Palade1 state that the wall of C. reinhardi is a multilayered structure about 40.0 nm thick and that the structure is consistent with the cellulose wall described from light microscope observations. The description of the wall given by Walne2,3 and by Cavalier-Smith4 is essentially similar to that given by Sager and Palade. Barnett and Preston5 using the freeze etching technique reported the presence of oriented microfibrils in the cell walls. The regular features were interpreted as being cellulose which was thought to be synthesized by small granules associated with the surface of the plasmalemma. In the related species C. moewusii the wall had a regular periodicity of 23.3 nm, and again the striations were interpreted6 as being cellulose fibrils, but it was noted that the spacings were smaller than those observed in other structures containing cellulose fibrils7.
Reciprocating thermocompressor performance with non-ideal component characteristics

AbstractUsing heat to compress a gas can have many technological uses including power generation and heat-activated cooling. A model is presented here for a reciprocating, displacer-based thermocom...
An evaluation of WLSMV and Bayesian methods for confirmatory factor analysis with categorical indicators

This Monte Carlo study evaluated the performance of three estimation methods in fitting confirmatory factor analysis (CFA) models for ordered categorical data, with the focus on data with non-normal underlying distributions and small sample sizes. The three methods are: weighted least squares with mean and variance adjusted (WLSMV), Bayesian with non-informative priors (BN), and Bayesian with informative priors (BI). Design factors included sample sizes, factor structures, underlying continuous distributions, and categorical distributions. Results were evaluated based on the model-data fit, point estimates, and standard errors of point estimates. Results showed that Bayesian methods encountered less convergence problems than WLSMV. Bayesian methods were robust to the non-normality of underlying continuous distributions. WLSMV tended to perform equally well or slightly better than Bayesian methods except for some conditions with small sample sizes or highly non-normal underlying distributions.
Buyer-seller relationships in the procurement of logistical services

This study presents a two-phase model of interfirm exchange in the logistical supply industry. The first phase uses transaction cost analysis to identify conditions leading to market-based transactions, unilateral agreements, and bilateral alliances. The second phase illustrates how formal controls and relational norms yield performance in market, unilateral, and bilateral governance systems. A test of the model with data from 189 logistical supply relationships suggests that bilateral alliances emerge through the interaction of user investments in the logistics supplier, supplier logistical services, and marketplace uncertainty. Bilateral alliances attain desired outcomes through participative management and flexibility. By contrast, market-based transactions yield desired outcomes through formalization and solidarity. Unilateral agreements gain performance through formalization, participation, information sharing, and solidarity. Implications for logistics management and theory are discussed.
Clinical and biochemical profiles suggest fibromuscular dysplasia is a systemic disease with altered TGF-β expression and connective tissue features

Fibromuscular dysplasia (FMD) is a rare, nonatherosclerotic arterial disease for which the molecular basis is unknown. We comprehensively studied 47 subjects with FMD, including physical examination, spine magnetic resonance imaging, bone densitometry, and brain magnetic resonance angiography. Inflammatory biomarkers in plasma and transforming growth factor β (TGF-β) cytokines in patient-derived dermal fibroblasts were measured by ELISA. Arterial pathology other than medial fibrodysplasia with multifocal stenosis included cerebral aneurysm, found in 12.8% of subjects. Extra-arterial pathology included low bone density (P<0.001); early onset degenerative spine disease (95.7%); increased incidence of Chiari I malformation (6.4%) and dural ectasia (42.6%); and physical examination findings of a mild connective tissue dysplasia (95.7%). Screening for mutations causing known genetically mediated arteriopathies was unrevealing. We found elevated plasma TGF-β1 (P=0.009), TGF-β2 (P=0.004) and additional inflammatory markers, and increased TGF-β1 (P=0.0009) and TGF-β2 (P=0.0001) secretion in dermal fibroblast cell lines from subjects with FMD compared to age- and gender-matched controls. Detailed phenotyping of patients with FMD allowed us to demonstrate that FMD is a systemic disease with alterations in common with the spectrum of genetic syndromes that involve altered TGF-β signaling and offers TGF-β as a marker of FMD.
Contribution of the amino and carboxyl termini for PHA‐4/FoxA function in Caenorhabditis elegans

FoxA transcription factors are central regulators of gut development in all animals that have been studied. Here we examine the sole Caenorhabditis elegans FoxA protein, which is called pha-4. We describe the molecular characterization of five pha-4 mutations and characterize their associated phenotypes. Two nonsense mutations are predicted to truncate PHA-4 after the DNA binding domain and remove the conserved carboxyl terminus. Surprisingly, animals harboring these mutations are viable, provided the mutant mRNAs are stabilized by inactivating the nonsense-mediated decay pathway. Two additional nonsense mutations reveal that the DNA binding domain is critical for activity. A missense mutation predicted to alter the PHA-4 amino terminus leads to a dramatic reduction in pha-4 activity even though the protein is expressed appropriately. We suggest that the PHA-4 amino terminus is essential for PHA-4 function in vivo, possibly as a transactivation domain, and can compensate for loss of the carboxyl terminus. We also provide evidence for autoregulation by PHA-4.
An information-theoretic framework for optimal temperature sensor allocation and full-chip thermal monitoring

Full-chip thermal monitoring is an important and challenging issue in today's microprocessor design. In this paper, we propose a new information-theoretic framework to quantitatively model the uncertainty of on-chip temperature variation by differential entropy. Based on this framework, an efficient optimization scheme is developed to find the optimal spatial locations for temperature sensors such that the full-chip thermal map can be accurately captured with a minimum number of on-chip sensors. In addition, several efficient numerical algorithms are proposed to minimize the computational cost of the proposed entropy calculation and optimization. As will be demonstrated by our experimental examples, the proposed entropy-based method achieves superior accuracy (1.4× error reduction) for full-chip thermal monitoring over prior art.
Mesenteric Ischemia in the Elderly

Intestinal ischemia is a relatively common disorder in the elderly and, if not treated promptly, still carries a high morbidity and mortality rate. High degree of clinical suspicion is of paramount importance in diagnosis, because there is no specific laboratory test available and physical examination findings may be subtle. Once the diagnosis is made, management relies on early resuscitation, identification, and treatment of the predisposing conditions, along with careful planning of the therapeutic invasive interventions, which altogether may help reduce the mortality and morbidity associated with this condition.
Transparency in 21st century fisheries management: Options for public participation to enhance conservation and management of international fish stocks

Abstract Effective implementation of international environmental and natural resource conservation agreements depends not only upon the cooperation of contracting parties, but also upon the ability of the agreement to win the continuing support and input of non‐governmental stakeholders. This view, accepted and advocated by nations in the 1992 Rio Declaration, Agenda 21, and the recent Aarhus Convention on Public Participation, is now being incorporated into modern regional fisheries management organizations. These and earlier fisheries organizations can benefit from an awareness of how other multilateral agreements that adhere to the Rio Declaration and Agenda 21 tenets have enhanced sustainable development through their provisions for transparency and public participation. This article surveys how these regimes have implemented the principles of access to information, access to decision‐making and access to justice, and makes corresponding recommendations to assist fisheries management organizations in ...
Seasonal and spatial variations in pelagic community respiration on the southeastern U.S. continental shelf

Abstract Pelagic microbial community respiratory rates on the southeastern continental shelf show strong seasonal changes, with summer maxima and winter minima. In nearshore waters 2 l −1 h −1 are similar to recent estimates of primary production. In outer shelf water >40 m, strongly influenced by the Gulf Stream, community respiration is 0.1–2.7 μM O 2 l −1 h −1 , exceeding primary production in summer. The changes in microbial community respiration are partially explained by changes in bacterial numbers. A related potential cause is the inverse relationship between limiting substrate concentration and temperature, affecting rates of growth and respiration, that has been found to exist for aerobic heterotrophy bacterial isolates in the laboratory. These processes result in shifts between net autotrophy in winter and net heterotrophy in summer for the community as a whole, with little excess organic production remaining for export to the ocean's interior.
Enhancing Grid Measurements: Wide Area Measurement Systems, NASPInet, and Security

Deregulation, market transactions, congestion management, and the separation of functions have created increasing complexity that is making it difficult to maintain situational awareness and supervision of power system performance over large areas. Past reliability events (such as blackouts) have highlighted the need for better situational awareness and advanced applications to improve planning, operations, and maintenance. The deployment of a continent- wide wide area measurement system (WAMS) is an important part of the solution to these complex problems, but it faces challenges with respect to communications and security.
Association between repeat sizes and clinical and pathological characteristics in carriers of C9ORF72 repeat expansions (Xpansize-72): a cross-sectional cohort study

Summary Background Hexanucleotide repeat expansions in chromosome 9 open reading frame 72 ( C9ORF72 ) are the most common known genetic cause of frontotemporal dementia (FTD) and motor neuron disease (MND). We assessed whether expansion size is associated with disease severity or phenotype. Methods We did a cross-sectional Southern blot characterisation study (Xpansize-72) in a cohort of individuals with FTD, MND, both these diseases, or no clinical phenotype. All participants had GGGGCC repeat expansions in C9ORF72 , and high quality DNA was available from one or more of the frontal cortex, cerebellum, or blood. We used Southern blotting techniques and densitometry to estimate the repeat size of the most abundant expansion species. We compared repeat sizes between different tissues using Wilcoxon rank sum and Wilcoxon signed rank tests, and between disease subgroups using Kruskal-Wallis rank sum tests. We assessed the association of repeat size with age at onset and age at collection using a Spearman's test of correlation, and assessed the association between repeat size and survival after disease onset using Cox proportional hazards regression models. Findings We included 84 individuals with C9ORF72 expansions: 35 had FTD, 16 had FTD and MND, 30 had MND, and three had no clinical phenotype. We focused our analysis on three major tissue subgroups: frontal cortex (available from 41 patients [21 with FTD, 11 with FTD and MND, and nine with MND]), cerebellum (40 patients [20 with FTD, 12 with FTD and MND, and eight with MND]), and blood (47 patients [15 with FTD, nine with FTD and MND, and 23 with MND] and three carriers who had no clinical phenotype). Repeat lengths in the cerebellum were smaller (median 12·3 kb [about 1667 repeat units], IQR 11·1–14·3) than those in the frontal cortex (33·8 kb [about 5250 repeat units], 23·5–44·9; p r =0·63; p=0·003) and age at sample collection ( r =0·58; p=0·006); we did not detect such a correlation in samples from the cerebellum or blood. When assessing cerebellum samples from the overall cohort, survival after disease onset was 4·8 years (IQR 3·0–7·4) in the group with expansions greater than 1467 repeat units (the 25th percentile of repeat lengths) versus 7·4 years (6·3–10·9) in the group with smaller expansions (HR 3·27, 95% CI 1·34–7·95; p=0·009). Interpretation We detected substantial variation in repeat sizes between samples from the cerebellum, frontal cortex, and blood, and longer repeat sizes in the cerebellum seem to be associated with a survival disadvantage. Our findings indicate that expansion size does affect disease severity, which—if replicated in other cohorts—could be relevant for genetic counselling. Funding The ALS Therapy Alliance, the National Institute of Neurological Disorders and Stroke, the National Institute on Aging, the Arizona Department of Health Services, the Arizona Biomedical Research Commission, and the Michael J Fox Foundation for Parkinson's Research.
Rare gases in separated whitlockite from the St. Severin chondrite: xenon and krypton from fission of extinct 244Pu

Abstract Helium, neon, argon, krypton and xenon data are presented from stepwise heating of samples of the mineral whitlockite from the chondritic meteorite St. Severin. The xenon is shown to be a uniform mixture derived from 244 Pu fission and rare-earth element spallation. The krypton similarly contains spallation products and 86 Kr from 244 Pu fission. Plutonium-244 fission yields of 86 Kr / 129 Xe / 131 Xe / 132 Xe / 134 Xe / 136 Xe = 1.9 ± 0.5/4.8 ± 5.5/24.6 ± 2.0/88.5 ±3.0/93.9 ± 0.8/  100 are obtained. The helium, neon and argon are dominated by spallation and radiogenic 4 He and 40 Ar. A pile neutron irradiation experiment does not yield a unique Pu/U ratio for this mineral but yields ratios varying from 0.045 down to 0.017. Both the high concentration of 244 Pu fission xenon and the high ratio of Pu/U previously reported by Wasserburg et al. ( J. Oeophys. Res . 74 , 4221–4232, 1969) are thus confirmed.
Elementary Education in England

(1905). Elementary Education in England. The Pedagogical Seminary: Vol. 12, No. 1, pp. 69-85.
Baculovirus replication induces the expression of heat shock proteins in vivo and in vitro

A recent handful of studies have linked baculovirus infection with the induction of heat shock proteins, a highly conserved family of cytoprotective proteins. Here, we demonstrate baculovirus-stimulated upregulation of hsp70 transcription in the natural host, Helicoverpa zea. Larvae lethally infected with Helicoverpa zea single nucleopolyhedrovirus (HzSNPV) accumulated hsp70 transcripts throughout the 72-hour course of infection in the midgut, hemocytes, and fat body. While a maximal 17- or 15-fold induction of hsp70 was noted in the midgut and hemocytes, respectively, by 72 hours postinfection, the level of hsp70 transcription in the fat body of larvae was greater than two orders of magnitude higher than in mock-infected larvae. These results were largely mirrored in cultures of infected cells, and a potentiation effect was observed in cells that were both heat shocked and infected. In contrast, Spodoptera frugiperda multiple nucleopolyhedrovirus and ultraviolet-inactivated HzSNPV did not stimulate hsp70 transcription in these non-permissive larvae and in cell culture, respectively. Taken together, this report documents baculovirus-mediated upregulation of hsp70 in the host and demonstrates the requirement for productive infection for hsp70 induction in vitro and in vivo.
Tibial plateau fracture following anterior cruciate ligament reconstruction

A case is presented of a tibial plateau fracture after previous anterior cruciate ligament reconstruction using patellar tendon autograft. The tibial plateau fracture occurred through the transosseous tibial tunnel and followed a torsional injury to the involved extremity. The stress riser effect of the transosseous tibial tunnel and the anatomic location of the cortical defect probably facilitated development of the fracture. Minimally invasive fixation of the fracture was effective in preserving knee stability without need for revision anterior cruciate ligament reconstruction.
The Predictive Capacity of the Theory of Reasoned Action and the Theory of Planned Behavior in Exercise Research: An Integrated Literature Review

Although the association between habitual exercise and health benefits has been well documented, physical activity levels in the United States are lower than is necessary to reach the nation's health potential. Beliefs that people hold can be a motivating factor in engaging in exercise. A critical review of the literature was conducted to assess the efficacy of using the Theory of Reasoned Action and the Theory of Planned Behavior with respect to exercise. Evidence for the predictive utility of the theories was found. The Theory of Planned Behavior is a more promising framework for the study of exercise because it includes beliefs about control of factors that would facilitate or inhibit carrying out exercise. Strategies for use of the theories in planning exercise programs are provided and suggestions for future research discussed.
Calcineurin, synaptic plasticity, and memory.

A long-held hypothesis in neuroscience holds that learning and memory mechanisms involve lasting changes in synaptic weights. Multiple mechanisms for producing such changes exist, of which NMDA-receptor–dependent long-term potentiation (LTP) is the most widely studied. Curiously, the relatively simple hypothesis that LTP plays a role in learning and memory has proven difficult to test. A current experimental strategy is to generate genetically altered mice with mutations in genes thought to be involved in LTP and assess the effects of these mutations both on LTP and animal behavior[1,2]. A difficulty associated with these approaches has been that they are not temporally or spatially refined. To alleviate this problem, Dr. Isabelle Mansuy and colleagues used an inducible and reversible transgene expression system in which transgene expression could be controlled on a week-to-week timescale to assess the effects of genetic reduction of the activity of a protein phosphatase known as calcineurin or PP2B in adult mouse forebrain[3,4].
Characterization of limonin glucoside metabolites from human prostate cell culture medium using high-performance liquid chromatography/electrospray ionization mass spectrometry and tandem mass spectrometry.

The metabolism of limonin 17-β-D-glucopyranoside (LG) by non-cancerous (RWPE-1) and cancerous (PC-3) human prostate epithelial cells was investigated using high-performance liquid chromatography/electrospray ionization mass spectrometry (LC/ESI-MS) with in-source fragmentation and tandem mass spectrometry (MS/MS). During positive ion LC/ESI-MS, LG formed an abundant sodiated species ([M+Na]+) while the protonated molecule was barely observable. [M+Na]+ further fragmented into the less abundant [LARL+H]+ and a predominantly protonated aglycone molecule (limonin) due to in-source fragmentation. The major metabolite, limonin A-ring lactone (LARL), formed an abundant protonated molecule that was fragmented into a protonated molecule of limonin by loss of one molecule of water. In MS/MS by collisionally activated dissociation (CAD), LG produced the sodiated aglycone, [aglycone+Na]+, while LARL fragmented into [M+H]+ of limonin and fragment ions resulted by further loss of water, carbon monoxide and carbon dioxide, indicating the presence of oxygenated-ring structures. The limits of detection of LG were 0.4 and 20 fmol in selected-ion monitoring (SIM) and selected-reaction monitoring (SRM) detection, respectively. Copyright © 2004 John Wiley & Sons, Ltd.
Penalization versus part-time occlusion and binocular outcome in treatment of strabismic amblyopia.

Objective: The purpose of the study is to compare the visual outcome of occlusion versus penalization treatment of strabismic amblyopia, with particular attention to binocularity outcome. Design: The study design was a retrospective study. Participants: Patients with strabismic amblyopia, 75 receiving penalization alone, 87 with a history of occlusion treatment who were later treated by penalization, and 30 treated by means of part-time occlusion (2 to 6 hours/day) participated in this study. Main Outcome Measures: Logarithm of the minimum angle of resolution (logMAR) visual acuity and binocularity index were measured. Results: No statistically significant difference was found between outcomes for the penalization groups with and without a history of occlusion, either by univariate analysis or by multivariate analysis controlling for initial-visit age, acuity, and binocularity status. One marginally significant outcome difference was found between the pure penalization and part-time occlusion groups by univariate analysis, but no significant difference was found in the multivariate analyses controlling for the same three variables at the initial visit. All visual outcome differences between the pure penalization and part-time occlusion groups were less than 1 10gMAR line visual acuity or less than a half-unit on the binocularity index. Conclusions: The study provided no evidence of a difference in visual function outcome between penalization and occlusion, in terms of either statistical or clinical significance, although limitations of the patient samples used preclude these data from showing conclusively that there was no such difference. The lack of any other study adequately comparing these two treatment methods, in combination with the current study's demonstration of the difficulty of making adequate retrospective-based comparison despite a large patient base (n = 1413), suggests that a large prospective, randomized comparative treatment trial is needed. If atropine penalization, with its high acceptability to patients and parents, is found to produce results comparable with those of occlusion in cases of mild-to-moderate amblyopia, as the current and previous smaller studies suggest, then reconsideration of the standard of care for such amblyopia cases is indicated.
Characterization of DNA polymerase beta mutants with amino acid substitutions located in the C-terminal portion of the enzyme.

We used quantitative complementation assays to characterize individual DNA polymeraseβ (Polβ) mutants for their ability to function in DNA replication and DNA repair. We also describe a screen for detecting imitator activity of DNA polymeraseβ mutants. By using these bioassays, together with DNA polymerase activity gels, we characterized 15 new DNA polymeraseβ mutants that display a wide spectrum of phenotypes. Most of these mutants are generally defective in their ability to synthesize DNA. However, two of our Polβ mutants show more complex phenotypes: they are able to function in DNA repair but unable to participate in DNA replication. One of our mutants displays imitator activity in vivo. Our work provides a model to study mutant mammalian enzymes inEscherichia coli with phenotypes that are otherwise difficult to assess.
Multi-component wind turbine modeling and simulation for wind farm operations and maintenance

Wind farms produce electricity and provide a source of renewable energy. The growth in wind farm installations in the past 10 years has led to an increase in the number of wind turbines reaching the end of their manufacturing warranties. As a consequence, the wind industry is now facing a rising cost of unscheduled maintenance, which is pushing up the operation and maintenance expenditures. Wind turbines experience stochastic loading due to seasonal variations in wind speed and direction. These harsh operational conditions lead to failures of wind turbine components, which are difficult to predict. Consequently, it is challenging to schedule maintenance actions that will avoid failures. In this paper, we derive algorithms for scheduling wind farm maintenance for wind turbines modeled explicitly as comprising multiple components: the gearbox, power generator, blades and control system. We perform simulations based on a real wind farm with 100 turbines and report on several wind farm performance measures. The results we obtain provide insights regarding how to efficiently manage limited maintenance resources in wind farms. For example, the results show that maintenance policies that consider performing maintenance on multiple components of a wind turbine on the same maintenance scheduled trip provides significant cost savings while reducing the number of turbine failures.
Novel nonlinear transmission of porphyrin complexes containing rhenium selenide clusters

Nonlinear transmission is found to be significantly enhanced by introducing heavy metal atoms on the periphery of macrocycle porphyrin complexes via rhenium selenide clusters that are coordinated to four pyridyl groups. Experiments on 5, 10, 15, 20-tetra(4-pyridyl) porphyrin (H 2 TPyP), CuTPyP, [Re 6 ( μ 3 -Se) 8 (PEt 3 ) 5 ] 4 (H 2 TPyP)(SbF 6 ) 8 (abbreviated as P5H 2 TPyP), and [Re 6 ( μ 3 -Se) 8 (PEt 3 ) 5 ] 4 Cu(TPyP)(SbF 6 ) 8 (abbreviated as CuP5TPyP) using 10 ns laser pulses at 523 nm show that, in contrast to CuTPyP and P5H 2 TPyP, which are saturable absorbers at a low fluence of 1-100 mJ/cm 2 and become nonlinear absorbers with a threshold larger than 1000 mJ/cm 2 at high fluence, CuP5TPyP exhibits an excellent nonlinear transmission performance with a threshold as low as 20 mJ/cm 2 . A bulky rhenium selenide cluster was coordinated to pyridyl groups in tetrapyridyl porphyrin. The modified copper (II) porphyrin complex CuP5TPyP has strong nonlinear absorption at 523 nm and synergistic interaction between CuTPyP and P5H 2 TPyP is one of possible mechanisms.
Controlling window protocols for time-constrained communication in a multiple access environment

For many time-constrained communication applications, such as packetized voice, a critical performance measure is the percentage of messages which are transmitted within a given amount of time after their arrival at a sending station. We examine the use of a group random access protocol based on time windows for achieving time-constrained communication in a multiple access environment. First, we formulate a policy for controlling protocol operation in order to minimize the percentage of messages with waiting times greater than some given bound. A semi-Markov decision model is then developed for protocol operation and three of the four optimal control elements of this policy are then determined.Although the semi-Markov decision model can also be used to obtain performance results, the procedure is too computationally expensive to be of practical use. Thus, an alternate performance model based on a centralized queueing system with impatient customers is developed. Protocol performance under the optimal elements of the control policy shows significant improvements over cases in which the protocol is not controlled in this manner. Simulation results are also presented to corroborate the analytic results.
Mechanisms of CO2 laser mitigation of laser damage growth in fused silica

Theoretical models for heating, evaporation, material flow, and stress and strain generation accompanying CO{sub 2} laser damage mitigation and surface treatment of fused silica are developed to aid understanding of scaling with process parameters. We find that lateral nonlinear heat transport is an important cooling mechanism, more significant than evaporative cooling. Scaling laws relating experiments with different set of parameters are presented. Transverse conduction, together with the increased thermal conductivity at high temperatures, allows a gentle evaporation regime at low laser intensity in which the rate can be controlled via laser fluence. For higher laser intensity, recoil momentum imparted by rapid evaporation generates pressure, which can lead to transverse flow of the melted material. Only a very thin layer can flow because viscosity increases rapidly with depth. Evaporation and flow are subject to instabilities that can impact surface quality, especially surface flatness, if large areas are processed. Also material flow can heal cracks and improve material quality. Analysis of stress indicates that maximal tensile stresses of order 0.1 GPa, comparable to the tensile strength, can be generated.
Kinetic evidence that arachidonate-induced calcium efflux from platelet microsomes involves a carrier-type ionophoric mechanism

Abstract Arachidonate, at concentrations up to 50 μM, induced dose-dependent calcium efflux from preloaded microsomes prepared from human platelets, but not from unilamellar egg phosphatidylcholine vesicles. Arachidonate-induced efflux from microsomes was not inhibited by indomethacin, 13-azaprostanoic acid, or catalase and superoxide dismutase, indicating that the release was due to arachidonate and not a metabolite. Linolenate (18:3, cis ) and linoleate (18:2, cis ) induced calcium efflux in a manner similar to arachidonate (20:4, cis ), while arachidate (20:0), linolelaidate (18:2, trans , elaidate (18:1, trans ), oleate (18:1, cis ), stearate (18:0) and palmitate (16:0) had no effect. An experimental method was developed for distinguishing between carrier ionophore, small aqueous pore (i.e., calcium channel), or large aqueous pore (i.e., detergent effect) mechanisms in vesicular efflux systems in which calcium efflux occurs over a period of minutes. This development predicted that with a carrier ionophore mechanism, an increase in either internal or external calcium should competitively inhibit 45 Ca efflux. In contrast, 45 Ca efflux by diffusion through a small aqueous pore or a large aqueous pore should be measurably insensitive to variations in internal or external calcium. These predictions were experimentally verified in the platelet microsomal system using efflux agents with known mechanisms. Efflux of 45 Ca by A23187, a calcium ion carrier ionophore, was sensitive to internal or external calcium competition, while alamethicin, a small aqueous pore channel model, and Triton X-100, a detergent which forms large aqueous pores, mediated 45 Ca efflux which was measurably insensitive to variations in internal or external calcium concentration. Arachidonate-induced 45 Ca efflux was inhibited by increasing either internal and external calcium concentration, suggesting that the fatty acid functions as a carrier ionophore. Arachidonate-induced 45 Ca efflux was also inhibited with extravesicular Sr 2+ , but not Mn 2+ or Ba 2+ . The dependence of the initial arachidonate efflux rate on arachidonate concentration showed that at least two aracidonates were contained in the calcium-carrier complex. These results are consistent with a model in which arachidonate (A) and an endogenous microsomal component (B) translocate calcium across the membrane through a carrier ionophore mechanism as part of a complex with a stoichiometry of A 2 B·Ca.
Cardiac output changes secondary to theophylline therapy in preterm infants

The cardiovascular effects of theophylline were studied in 11 clinically stable preterm infants. Theophylline was given as aminophylline using a loading dose of 6.8 mg/kg and a maintenance dose of 2 mg/kg every 8 hours intravenously. Cardiac output, stroke volume, and heart rate were measured using a combination of pulsed Doppler ultrasound and M-mode echocardiography. Compared with day 0, an increase was found in both cardiac output (P
Treatment of chlamydial infections

Introduction: Chlamydiae are obligate intracellular bacterial pathogens whose entry into mucosal epithelial cells is required for intracellular survival and subsequent growth. The life cycle of Chlamydia spp. and the ability to cause persistent, often subclinical infection, has major ramifications for diagnosis and treatment of C. trachomatis and C. pneumoniae infections in humans. Areas covered: This up-to-date review describes the current state of knowledge of antimicrobial susceptibilities and treatment of genital infections due to C. trachomatis and respiratory infections due to C. pneumoniae. Expert opinion: Chlamydiae are susceptible to antibiotics that interfere with DNA and protein synthesis, including tetracyclines, macrolides and quinolones, which are the compounds that have been most extensively studied and used for treatment of human infection. Treatment of individuals with C. trachomatis genital infection prevents sexual transmission and complications, including pelvic inflammatory disease. T...
A review of two studies of elasticity in academe

Abstract This is a review of a paper by Chang and Tuckman on elasticity of demand for college faculty at different types of institutions, and one by Chressanthis on elasticity of demand for enrollment by class standing at a state college. While Chang and Tuckman attribute some of the changes in the distribution of faculty across ranks to the different responsiveness to salary changes by institutions with different missions, I attribute these changes in rank distributions to the pattern of academic hiring and promotions, as constrained by the tenure system. Chressanthis finds variation by class standing in elasticity of demand for enrollment at a state college, and therefore recommends a two-tier tuition policy.
Stationary populations with below-replacement fertility

With constant immigration flows, there are an uncountably infinite number of stationary populations for any below-replacement fertility schedule f and life table l. Each corresponds to a different pattern of age-specific annual immigrant inflows. This brief paper derives a general formula for the age structure of these populations, provides numerical examples using contemporary Austrian demographic data, and illustrates an application of the main relationship to the study of stationary dependency ratios.
Intra-Industry Specialization in United States–China Trade

Frictions in U.S.–China bilateral trade relations have intensified in recent years. Changes in intra-industry specialization indicators are used to assess factor adjustment pressures that may have been experienced by U.S. and Chinese industries from recent growth in bilateral trade. Many industries experienced large increases in intra-industry trade over the 2000–10 period. Only 14 of 62 U.S. industries may have experienced factor adjustment pressures. Most U.S. industries gained from growth in U.S.–China trade. Nine Chinese industries may have faced factor adjustment pressures. The United States should refrain from using trade remedy measures to address bilateral trade frictions and focus instead on improving trade relations.
Promoter analysis of the vesicular stomatitis virus RNA polymerase

We have reconstituted synthetic VSV nucleocapsids from synthetic RNA and purified VSV N protein which are active as templates for transcription by the viral RNA polymerase in vitro. Utilizing progressively shorter RNAs in this system, we found that nucleocapsids containing just the 3' 22 nucleotides of either (-) or (+) strand viral RNA served as good transcription templates. Of this sequence, optimal transcription required the 15-17 3'-terminal nucleotides as a promoter. We showed with two VSV serotypes that the 3'-terminal nucleotides, UGC, were absolutely essential for transcription of the synthetic nucleocapsid by added RNA polymerase. Addition of extra nucleotides to the normal 3' end of nucleocapsid RNA totally abolished activity. The requirements for the nucleotides from positions 4 to 17 from the 3' end were less stringent, since individual changes in this region had variable effects on transcription, from partial inhibition to stimulation. The characterization of the transcription products synthesized from a variety of nucleocapids showed both full-length products and short (8-12 nucleotides) products which initiated directly at the 3' end but prematurely terminated. The VSV RNA polymerase was capable of adding one or more nontemplated bases to the 3' end of the product RNA depending on the nucleocapsid RNA sequence and the presence or absence of 5' triphosphates on the RNA.
Pressure and temperature effects in bituminous coal pyrolysis : experimental observations and a transient lumped-parameter model

Abstract Total weight loss and yields of tar, light gases and pyridine-extractables of cooled chars from pyrolysis of 63–75 μm particles of Pittsburgh No. 8 bituminous coal, as affected by total pressure (0.1–1 MPa He) and final temperature (753–1233 K) were measured at a nominal heating rate of 1000 Ks − 1 , using an electrical screen heater reactor. Molecular weight distributions of tars and changes in coal particle morphology during pyrolysis were determined. Above 973 K, with an increase in pressure from 0.1 to 1 MPa, tar yield declined by 6–7 wt% (daf coal basis); increases in the yields of char (~5 wt%) and light gases (mainly C 1 C 3 hydrocarbons) (~ 1 wt%) accounted for most or all of this tar loss. Tar MW declined slightly with increasing temperature from ~ 850 to 973K at 0.1 MPa, and from ~ 850 to 1233K at 1 MPa. It also decreased moderately with increasing pressure from 0.1 to 1 MPa at all temperatures from 850 to 1200 K, except in the neighbourhood of 970 K, where no change with pressure was apparent. A mathematical model was developed to predict tar and extractables yields from rapid pyrolysis of softening coals. The model accounts for intraparticle transport and secondary reactions of liquids generated by coal pyrolysis, and satisfyingly captures important features of the current experimental data, e.g. temperature and pressure effects on tar yields, and rapid changes in extractables yields from 760 to 900 K at 0.1 and 1 MPa. The data and modelling results indicate that secondary reactions of liquids within the coal significantly affect tar release at temperatures ⩾ 1000 K.
Riblets as a Viscous Drag Reduction Technique

T viscous drag of turbulent boundary layers is a significant factor contributing to the fuel costs of the airlines. Several studies have indicated that microsurface geometry variations which change the near-wall structure of the flow have been effective in reducing drag. Summarized here is an investigation into the verification and extension of the most promising of these riblet variations.
Histologic models for optical tomography and spectroscopy of tissues

Histologic information is often the ground truth against which imaging technology performance is measured. Typically, this information is limited, however, due to the need to excise tissue, stain it and have the tissue section manually reviewed. As a consequence, histologic models of actual tissues are difficult to acquire and are generally prohibitively expensive. Models and phantoms for imaging development, hence, have to be simple and reproducible for concordance between different groups developing the same imaging methods but may not reflect tissue structure. Here, we propose a route to histologic information that does not involve the use of human review nor does it require specialized dyes or stains. We combine mid-infrared Fourier transform infrared (FT-IR) spectroscopy with imaging to record data from tissue sections. Attendant numerical algorithms are used to convert the data to histologic information. Additionally, the biochemical nature of the recorded information can be used to generate contrast for other modalities. We propose that this histologic model and spectroscopic generation of contrast can serve as standard for testing and design aid for tomography and spectroscopy of tissues. We discuss here the biochemical and statistical issues involved in creating histologic models and demonstrate the use of the approach in generating optical coherence tomography (OCT) images of prostate tissue samples.
The Inheritance of Egg Shell Color

Abstract ECONOMIC studies have shown definite consumer preference based on egg shell color. In North Carolina the State College Extension Service has observed that brown-shelled eggs which are sorted on the basis of color sell more rapidly than brown-shelled eggs which are unsorted and sold in mixed shades of brown. In most strains which lay brown-shelled eggs, variation in color is so great that sorting of different shades is not practical. The possibility that a uniformly dark shell color might be secured by breeding was considered. In order to determine the limitations of selective breeding, it is desirable to know something of the nature of the inheritance of egg shell color. Hurst (1905) and Warren (1930) have reported that the progeny of matings involving white- and dark-shelled breeds of chickens laid eggs of an intermediate color. Benjamin (1920) found that dominance was not involved in the inheritance of egg shell color . . .
Acceleration of Electrocatalytic Activity on Pt–Sn Nanoparticles

A SnCl 2 shell on Pt metal core nanoparticle synthesis technique has recently been demonstrated to permit electrostatic layer-by-layer (LbL) assembly of well-ordered electrocatalysts without precipitation onto porous carbon supports. In this paper, the electrocatalytic activity of the LbL-assembled Pt nanoparticles is shown to depend critically upon removal of surface-adsorbed Sn (Sn ads ). By subjecting the synthesized Pt nanoparticle electrodes to potential sweeps greater than 1.0 V vs reversible hydrogen electrode, Sn ads are removed and a nearly threefold enhancement in oxygen reduction reaction (ORR) specific activity over commercial catalysts is obtained. In contrast to this electrochemical acceleration approach, we also investigate electroless, wet-acceleration methods for Sn ads removal. Energy-dispersive spectroscopy and inductively coupled plasma-mass spectrometry are used to quantify the Pt/Sn ratio in the electrode assemblies as a function of immersion time in solution (both alkaline and acidic) and during electrochemical acceleration, respectively. Charging current for the underpotential deposition of protons on the Pt nanoparticle surface is used to monitor the removal of Sn ads during electrochemical acceleration, followed by ORR activity measurement in saturated perchloric acid (HClO 4 ). Wet-chemical acceleration in NaOH solution is found to remove similar amounts of Sn as compared to the electrochemical technique.
Age-dependent reduction of cortical contusion volume by ketones after traumatic brain injury

Although the adult brain primarily metabolizes glucose, the evidence from the starvation literature has demonstrated that the adult brain retains some potential to revert to ketone metabolism. This attribute has been exploited recently to shift the adult brain toward ketone metabolism after traumatic brain injury (TBI), resulting in increased cerebral uptake and oxidation of exogenously administered ketones and improved cerebral energy. The ability to utilize ketones as an alternative substrate decreases with cerebral maturation, suggesting that the younger brain has a greater ability to metabolize this substrate and may be more receptive to this therapy. It was hypothesized that the administration of ketones after TBI in the developing brain will decrease lesion size in an age-dependent manner. Postnatal day (PND) 17, 35, 45, and 65 rats were placed on either a standard or ketogenic (KG) diet after controlled cortical impact (CCI) injury. PND35 and PND45 KG-fed animals showed a 58% and 39% reduction in cortical contusion volume, respectively, at 7 days post-injury. The KG diet had no effect on contusion volume in PND17 and PND65 injured rats. Both PND35 and PND45 KG-fed groups revealed fewer Fluoro-Jade-positive cells in the cortex and hippocampus at 6 hr and showed earlier decreases in plasma lactate compared to standard-fed animals. The age-dependent ketogenic neuroprotection is likely related to age-related differences in cerebral metabolism of ketones and suggests that alternative substrate therapy has potential applications for younger head-injured patients.
Prediction of long-term cognitive outcome of brain injury with neuropsychological, severity of injury, and demographic data

A comparison was made of the relative power of a brief post-injury neuropsychological assessment and a brain-injury severity measure (PTA) to predict long-term cognitive outcome after severe brain injury. Subjects were 78 patients with severe brain injury. Regression analysis revealed that neuropsychological variables were as predictive of outcome as PTA. A combination of neuropsychological, brain-injury severity, and demographic variables predicted a substantial proportion of variance in both general cognitive ability and memory functioning at outcome. Removal of PTA from the set of predictors had only modest impact on predictive power, suggesting that, in the absence of accurate injury severity data, meaningful prediction about long-term cognitive outcome can still be made.
SURVEY RESULTS ON MEDICAL AND SURGICAL FOLLOWUP OF PATIENTS WITH VESICOURETERAL REFLUX FROM AMERICAN ASSOCIATION OF PEDIATRICS, SECTION ON UROLOGY MEMBERS

Purpose: Little data are available on the appropriate followup protocols for patients treated medically or surgically for vesicoureteral reflux. We surveyed urologists who primarily practice pediatric urology to determine current practice patterns for following patients treated for vesicoureteral reflux.Materials and Methods: A 1-page survey was mailed to the 225 members of the American Academy of Pediatrics, Section on Urology. The mailing roster and labels were provided by the American Academy of Pediatrics. The survey included questions on the followup of patients with low and high grade reflux treated medically or surgically. Returned surveys were blindly tabulated by 2 independent reviewers (F. A. F. and P. H. M.).Results: Of the 225 surveys 155 were returned and analyzed for an overall response rate of approximately 61%. Urine culture is routinely performed by 64% and 71% of respondents to follow children with uncorrected low grade reflux and those with high grade reflux undergoing medical treatment...