cssi/SciSciGPT-SciSciNet huggingface dataset:
Permeability of fluorescein-labelled dextrans in fundus fluorescein angiography of rats and birds.

Abstract Intravenously injected sodium fluorescein (mol. wt. 376) does not leak from normal mammalian retinal vessels. However, sodium fluorescein (NaFl) leaks profusely from the avian pecten, a pigmented, vascularized organ located atop the optic nerve head and protruding into the vitreous cavity. Since molecular size is one property of molecules which governs their permeability in a given blood vessel system, the permeability of these two intraocular blood vessel systems to fluorescein labelled compounds of selected molecular sizes was compared in vivo by standard fluorescein angiographic techniques. The compounds used were fluorescein isothiocyanate (FITC) labelled dextrans of the following average dimensions: FITC-Dex 3 (mol. wt. 3000, radius, 12 A); FITC-Dex 20 (mol. wt. 20 000, 32 A); FITC-Dex 40 (mol. wt. 40 000, 45 A); FITC-Dex 70 (mol. wt. 70 000, 58 A). Normal rat retinal vessels were impermeable to any of these dextrans. In contrast to the known response to NaFl, the pigeon pecten effectively excluded each of the FITC Dextrans from entering the vitreous. It is thought that dissimilar mechanisms are responsible for the individual permeability responses of these mammalian and avian intraocular vessel systems.
Accuracy of plain films, and the effect of experience, in the assessment of ankle effusions.

To investigate the accuracy of plain radiographs, and the effect of observer experience, in the assessment of ankle effusions compared with an MRI gold standard. Anteroposterior (AP) and lateral radiographs of the ankle of 39 patients were evaluated by four observers, ranging from first-year radiology resident to an attending musculoskeletal radiologist. Observers independently graded the lateral films from 0 to5 at one sitting, and the AP films at a second sitting. All patients had an MRI scan performed within 48 h of the ankle radiographs, on which distention of the anterior recess was used as the gold standard for an effusion. Lateral radiographs had variable sensitivity (range 17―63%), but specificity (81–94%) was usually high. AP radiographs similarly had variable sensitivity (15–55%), but their specificity (63–75%) was surprisingly good. Overall, sensitivity and specificity were inversely proportional and more related to individual variability than experience (observer 1, 53% and 81%; observer 2, 17% and 94%; observer 3, 63% and 88%; observer 4, 21% and 94%); however, individual sensitivity and specificity were consistent between AP and lateral radiographs (observer 1, 53% and 81%, 50% and 65%; observer 2, 17% and 94%, 15% and 75%), observer 3, 63% and 88%, 55% and 63%; observer 4, 21% and 94%, 25% and 70%). Positive predictive value was reasonably good for lateral radiographs (range 75―86%); however, it was fairly low for AP radiographs (38–61%). Negative predictive value was low for both lateral (50–67%) and AP (47–58%) radiographs. Accuracy was low for both AP (45–59%) and lateral (53–74%) radiographs. As expected, individual accuracy was consistently higher for lateral radiographs than for AP radiographs (observer 1, 65% and 58%; observer 2, 53% and 45%; observer 3, 74% and 59%; observer 4, 54% and 48%). For the diagnosis of ankle effusions the overall accuracy of radiographs was surprisingly low. Quite surprisingly, the diagnosis of effusions on AP radiographs was not much poorer than on lateral films. Results, however, varied little with experience and training.
Smoothed analysis of the perceptron algorithm for linear programming

The smoothed complexity [1] of an algorithm is the expected running time of the algorithm on an arbitrary instance under a random perturbation. It was shown recently that the simplex algorithm has polynomial smoothed complexity. We show that a simple greedy algorithm for linear programming, the perceptron algorithm, also has polynomial smoothed complexity, in a high probability sense; that is, the running time is polynomial with high probability over the random perturbation.
302. Anti-Angiogenic Treatment Enhances Anti- Tumor Effects of an Oncolytic Virus in an Experimental Rat Glioma Model

Oncolytic viruses (OVs) are viruses with selective ability to replicate & lyse in tumors. Recent results from clinical trials have established their safety yet efficacy remains elusive. We are examining stromal responses elicited upon treatment of intracerebral brain tumor by hrR3 (type 1 Herpes simplex virus (HSV-1) derived OV). Effect of OV treatment on host tumor vasculature. 7 days post intracerebral tumor implantation (D74HveC rat glioma cells), rats were treated with intratumoral injection of hrR3 or PBS. Effect of OV on tumor vasculature was evaluated by i.v injection of FITC- dextran 3 days post OV infection. Our results have uncovered a significant increase in vascular permeability in response to OV treatment of tumors. Quantification of the leaked fluorescent dye in tissue revealed that vascular leakage in OV treated groups was 4 fold higher than in control PBS injected animals (35.7 |[plusmn]| 6 (OV) Vs (8.9 |[plusmn]| 0.3) (PBS). This observation was confirmed on ultra high field, high resolution MRI performed at 8.0-Tesla using ultrasmall particle of iron oxide (USPIO) enhanced gradient echo sequence. Additionally this OV induced vascular leakage was not evident in Cyclophosphamide (CPA) treated immune suppressed rats. These results indicate that increased vessel permeability was a result of endothelial cell activation in response to OV infection. This increased permeability allows for host immune cell infiltration into the tumor which is deleterious to the presence of OV. Effect of OV treatment on angiogenesis. The host immune system uses the OV induced breach in Blood Brain Barrier (BBB) to infiltrate tumor tissue with macrophages resulting in destruction of therapeutic OV. Activated macrophages can secrete VEGF and initiate an angiogenic response. Tumor bearing rats treated with OV or PBS, were sacrificed prior to death and vessel density was evaluated in size matched tumors. The number of vessels/view field, was quantified by RECA-1 and CD31 immunostaining for endothelial cells. Neovascularization was significantly greater in tumors treated with OV compared to control (OV: 101 |[plusmn]| 21.6; versus PBS : 19.8 |[plusmn]| 10) (P = 0.0037). Effect of pretreatment with an anti-angiogenic agent on OV mediated therapy. Based on the above findings we hypothesized that a reduction in tumor blood vessels prior to OV infection would result in reduced tumor infiltration of host inflammatory cells leading to enhancement of OV efficacy. We tested this hypothesis by using Cilengitide (cRGD), a known anti-angiogenic agent & antagonist of integrin |[alpha]|v|[beta]|3. Pretreatment of rats with a single dose of cRGD prior to OV injection significantly increased survival of rats compared to rats treated with a single agent (median survival: PBS: d12; cRGD: d13; OV: d18; cRGD + OV: d22) (P < 0.05 between OV and cRGD + OV).
The effectiveness of the erratum in avoiding error propagation in physics

The propagation of errors in physics research is studied, with particular attention being paid to the effectiveness of the erratum in avoiding error propagation. We study the citation history of 17 physics papers which have significant errata associated with them. It would appear that the existence of an erratum does not significantly decrease the frequency with which a paper is cited and in most cases the erratum isnot cited along with the original paper. The authors comment on implications for the responsibilities of authors.
Can We Predict Who Will Be Alive and Well After Transcatheter Aortic Valve Replacement? Is That Useful to Individual Patients?

The goal of health care is to optimize both quantity and quality of life for patients. Among select patients with severe symptomatic aortic stenosis, transcatheter aortic valve replacement (TAVR) can, on average, improve both survival and health status (i.e. symptoms, functional status, and quality of life).1,2 Yet, the technology is currently limited to patients who are either ineligible or at high risk for open surgical AVR. The result is that TAVR is used in older patients with multi-morbidity and frailty. As such, success is far from guaranteed for each of these complex cases. Indeed, despite the overall benefits seen in the Placement of AoRTic TraNscathetER Valve (PARTNER) trial, approximately 1 in 5 patients undergoing TAVR died within 6-months.3 An unmet need is to better determine, prior to TAVR, which individual patients are unlikely to achieve a "good" outcome.
Phosphorus(III) oxide: The reaction of tetraphosphorus hexaoxide with group VIB metal carbonyls

Abstract The monosubstituted Group VIB metal carbonyl derivatives of phosphorus(III) oxide, P 4 O 6 , have been prepared and characterized by mass spectrometry, and IR and 31 P NMR spectroscopy. The 31 P NMR chemical shift of the uncoordinated phosphorus(III) atoms in the P 4 O 6 cage is found to be a measure of the extent of interaction between the coordinated phosphorus atom and the Lewis acid metal carbonyl site. The P 4 O 6 cage appears to be a strong π acceptor ligand.
Parametric time delay modeling for floating point units

A parametric time delay model to compare floating point unit implementations is proposed. This model is used to compare a previously proposed floating point adder using a redundant number representation with other high-performance implementations. The operand width, the fan-in of the logic gates and the radix of the redundant format are used as parameters to the model. The comparison is done over a range of operand widths, fan-in and radices to show the merits of each implementation.
Next-generation soft-tissue-friendly large-diameter femoral head

Abstract Large-diameter femoral heads are being used increasingly in total hip arthroplasty (THA) to minimize hip dislocation risk. However, recent studies have shown that conventional large heads can impinge on native soft tissues, particularly the iliopsoas, leading to activity-limiting anterior hip pain. To address this, a novel soft-tissue-friendly anatomically contoured femoral head (ACH) was developed. This paper describes the design rationale and pre-clinical testing of the ACH implant. The test results demonstrate that anatomical contouring of large-diameter femoral heads for soft-tissue relief can be accomplished without affecting dislocation resistance, femoroacetabular contact area, or wear performance in ceramic-on-polyethylene implants.
The biochemistry of electrolyte transport.

Summary A number of observations pertaining to the linkage of electrolyte transport to cellular metabolism are reviewed. Cellular respiration is apparently the source of energy for sodium ion transport in the frog skin, in the proximal tubule of Necturus and in the kidney slice, but there is no convincing evidence that oxygen is necessary for electrolyte transport in the intact kidney. The marked differences in the enzyme patterns of renal glomerula, cortex and medulla suggest different energetic coupling in the various parts of the nephron. In the production and secretion of ammonia and hydrogen ions, enzymes probably participate directly in the transfer of these ions. A particularly attractive hypothesis of ion transport involving diglycerate and phosphatidic acid has been presented by Hokin and Hokin.
The synthesis of certain 4‐mono‐ and 4,7 dihydroxy‐1,10‐phenanthrolines

Aminocrotonates and cinnamates formed by the action of ethyl acetoacetate and ethyl benzoylacetate on substituted 8-aminoquinolines have been cyclized to 4-hydroxy and 4,7-dihydroxy-1,10-phenanthrolines.
Lumbar spine bone mineral density in US adults: demographic patterns and relationship with femur neck skeletal status

This analysis examines lumbar spine bone mineral density (BMD) of US adults from NHANES 2005–2008 by age, sex, and race/ethnicity. Prevalence of low spine BMD and agreement between the prevalence of low BMD at the spine and femur neck in older adults are also assessed. Lumbar spine BMD data from a representative sample of the US population have not been previously available. We used data from the National Health and Nutrition Examination Survey 2005–2008 to examine demographic patterns in lumbar spine BMD among US adults age ≥20 years and the prevalence of low lumbar spine BMD in adults age ≥50 years. Agreement between the prevalence of low BMD at the femur neck and spine in older adults was also assessed. Dual-energy X-ray absorptiometry was used to measure lumbar spine and femur neck BMD. World Health Organization definitions were used to categorize skeletal status as normal, osteopenia, or osteoporosis. Compared to non-Hispanic whites, non-Hispanic blacks had higher and Mexican Americans had lower lumbar spine BMD. Lumbar spine BMD declined with age in women, but not in men. Approximately 4.7 million (10%) older US women and 1 million (3%) older men had lumbar spine osteoporosis in 2005–2008. Roughly one third of them differed in skeletal status at the spine and hip but most were normal at one site and osteopenic at the other. Only 3–10%, depending on sex, had osteoporosis at one skeletal site but not at the other skeletal site. Between 76% and 87% with discordant skeletal status had lumbar spine T-scores within 1 unit of the category threshold. These findings suggest that measuring either the femur neck or the lumbar spine will correctly classify the majority of individuals who present for care as osteoporotic or not.
A design for long-term status and trends monitoring

Abstract The statistical limitations of sampling make monitoring of environmental status and trends very difficult. The reason for the difficulty is that, at the time of the design of a survey, the timing, location, nature and extent of any impact is unknown. This lack of prior knowledge introduces a large element of chance into a monitoring design which must detect population events from data collected at fixed location, reference stations. Instead, rotational survey designs are recommended for the design of long-term monitoring programs. This monitoring scheme overcomes traditional limitations by replacing a subset of the sampling stations each year to continually survey new locations which would otherwise go unsampled. Sampling with partial replacement has the additional advantages of minimizing the bias in estimates of status while continually updating prior estimates through time series calculations.
Modeling atmospheric O2 over Phanerozoic time

A carbon and sulfur isotope mass balance model has been constructed for calculating the variation of atmospheric O2 over Phanerozoic time. In order to obtain realistic O2 levels, rapid sediment recycling and O2-dependent isotope fractionation have been employed by the modelling. The dependence of isotope fractionation on O2 is based, for carbon, on the results of laboratory photosynthesis experiments and, for sulfur, on the observed relation between oxidation/reduction recycling and S-isotope fractionation during early diagenetic pyrite formation. The range of fractionations used in the modeling agree with measurements of Phanerozoic sediments by others. Results, derived from extensive sensitivity analysis, suggest that there was a positive excursion of O2 to levels as high as 35% during the Permo-Carboniferous. High O2 at this time agrees with independent modeling, based on the abundances of organic matter and pyrite in sediments, and with the occurrence of giant insects during this period. The cause of the excursion is believed to be the rise of vascular land plants and the consequent increased production of O2 by the burial in sediments of lignin-rich organic matter that was resistant to biological decomposition.
What are the metes and bounds of a wave

Abstract Seaward extension of national boundaries raises a number of problems. Oceans are fluids and boundary requirements differ from those on land. Water mass and fish‐movements do not respect political boundaries. National perceptions of ocean resource values vary, as do expectations of the benefits that can be derived from the oceans. Extensions of national jurisdiction may solve some conflicts, but neighbor‐to‐neighbor relations are likely to be aggravated as ecological processes mediate opportunities and interactions between nations.
Individual differences in dysfunctional automatic thinking and parental bonding: specificity of maternal care

Although research has assessed the relationship between variables such as attachment and dysfunctional beliefs, little research has addressed the link between individual differences in parental bonding and automatic thinking. To address this question, analyses were conducted with two subject samples who had completed measures of parental bonding, positive and negative automatic thinking, and affective symptoms. After controlling for affective symptomatology, regression analyses indicated that maternal care was consistently associated with both positive and negative cognitive self-statements. In a subsequent analysis using the first sample, individuals who did not evidence elevated affective symptomatology were divided into positive or negative bonding groups. Results indicated that those with positive maternal bonding experiences reported more positive and fewer negative thoughts than did those with poor maternal bonding. These data suggest that ambient levels of automatic thinking may explain some of the increased risk experienced by individuals with poor bonding.
The Functions and Inhibition of the Membrane Glycoproteins of Paramyxoviruses and Myxoviruses and the Role of the Measles Virus M Protein in Subacute Sclerosing Panencephalitis

The F glycoprotein of paramyxoviruses is responsible for cell fusion and hemolysis and for virus penetration via fusion of viral and cell membranes. These functions are activated by specific proteolytic cleavage of an inactive precursor (F0) into two disulfide-linked polypeptides (F1 and F2). The susceptibility of the F0 protein to cleavage by a host protease is a major determinant of virus host range and virulence. Synthetic oligopeptides that mimic the N-terminal region of the F1 polypeptide are specific inhibitors of paramyxoviruses, and oligopeptides that mimic the N-terminus of the HA2 polypeptide of influenza virus, also generated by cleavage, specifically inhibit that virus. Antibodies to F protein prevent the spread of paramyxovirus infection via membrane fusion, but antibodies to HN protein do not, although they neutralize released virus. These results and previous findings that formalin-treated virus does not induce antibodies to F protein provide an explanation for atypical measles. The HN protein has both receptor-binding and neuraminidase activities, and Cl- inhibition of neuraminidase may modulate these antagonistic activities. Studies in patients with subacute sclerosing panencephalitis (SSPE) suggest that there is a host restriction of synthesis of the M protein of measles virus in brain cells which is involved in the abortive, persistent infection that causes SSPE.
RELACION FAMILIA Y ESCUELA:: UN ESTUDIO COMPARATIVO EN LA RURALIDAD

In spite of the fact that the family is the first socializing agency during childhood, at present the family does not play this role alone because other agents, such as the school, share this important function. Studies about the relationship between family and school are scarce especially in rural areas. Thus, it was important to carry out a descriptive-comparative study about the topic in two elementary schools in different rural areas. The information was obtained from the application of various interviews to mothers, teachers and students from 1st to 6th grade as well as from schools’ documents and complemented with ethnographic observations. The results show that families as well as students give great importance to school and have high educational expectations. The teachers‘ perceptions, however, are different. A high percentage of the teachers of one of the schools studied believe families do not perceive school as important and do not participate in school activities.
Apolipoprotein E in Alzheimer's disease risk and case detection : A case-control study

Abstract The objective of this study was to describe the association between the epsilon 4 allele of the apolipoprotein E gene (APOE E4) and Alzheimer's disease (AD) and to evaluate APOE E4 genotyping as a test for AD. The study base of this case-control study included about 23,000 persons 60 year of age or greater (a large health maintenance organization); the demographic characteristics of this group are similar to those of the surrounding area. Analysis focused on 234 Caucasian probable AD patients first identified between 1987 and 1993; and 304 cognitively intact controls of similar age, sex, and race who were randomly selected from the same study base. All cases were examined and diagnosed by study physicians using standard protocols. All subjects participate in continuing annual follow-up testing to verify their cognitive status. APOE genotypes were determined from blood samples using standard laboratory methods. Subject characteristics and diagnoses were obtained from interviews, diagnostic examination, or medical record review. Heterozygous E4 individuals had a crude odds ratio of 3.1 (2.1–4.5) for AD compared to those with no E4, while homozygous E4 subjects had an odds ratio of 34.3 (8.0–146.3) for AD. As an indicator of AD, having one E4 allele showed a sensitivity of 0.52 and a specificity of 0.74. Homozygous E4 genotype had a sensitivity of 0.23 and a specificity of 0.99 (when compared to non-E4 genotypes). Cardiovascular disease differed in cases and controls, but did not confound or modify the APOE E4-AD association. In this study base, the APOE E4 allele was a significant risk factor. However, considering either homozygous or heterozygous E4 genotype as a screen or diagnostic marker for AD would miss many true cases and could misclassify many normals as AD.
Nonlinear adaptive control with parameter estimation of a CSTR

Abstract The goal of this paper is to describe a linearizing feedback adaptive control structure which guarantees high quality regulation of the output error in the face of unknown parameters. The effectiveness of this control structure is demonstrated on a continuous stirred tank reactor in two instances. The first is when there is full state feedback and the second when only temperature measurements are available. In the latter a nonlinear observer is constructed to infer conversion. In both cases conditions for asymptotic stability are presented and discussed.
Particles and microfluidics merged: perspectives of highly sensitive diagnostic detection

There is a growing need for diagnostic technologies that provide laboratories with solutions that improve quality, enhance laboratory system productivity, and provide accurate detection of a broad range of infectious diseases and cancers. Recent advances in micro- and nanoscience and engineering, in particular in the areas of particles and microfluidic technologies, have advanced the “lab-on-a-chip” concept towards the development of a new generation of point-of-care diagnostic devices that could significantly enhance test sensitivity and speed. In this review, we will discuss many of the recent advances in microfluidics and particle technologies with an eye towards merging these two technologies for application in medical diagnostics. Although the potential diagnostic applications are virtually unlimited, the most important applications are foreseen in the areas of biomarker research, cancer diagnosis, and detection of infectious microorganisms.
Template matching in pyramids

Abstract Correlation of a small “template” array with a large image array is an operation commonly used in image analysis. Edge detection, line and corner finding are some applications of the technique. Two problems with template matching are its computational cost and its sensitivity to noise. Pyramids (image hierarchies incorporating variable resolution) allow template matching to be performed in a new manner. Hierarchical template matching allows both a savings in computation time (by a problem-dependent amount) and a considerable degree of insensitivity to noise. These techniques are introduced and analyzed through a series of simple and empirical examples. An important feature of template matching locations that would be difficult to enforce and evene to express, in the traditional nonhierarchical framework. The hierarchical approach admits a large variety of image-processing operations.
The human Leydig insulin-like (hLEY I-L) gene is expressed in the corpus luteum and trophoblast.

A novel member of the insulin superfamily has previously been shown to be expressed only in porcine pre and postnatal Leydig cells and its human analogue demonstrated in the human testes but not in other organs and hence has been tentatively termed Leydig insulin-like peptide (Ley I-L). However, we have detected hLey I-L gene expression in the cyclic human corpus luteum and trophoblast by the reverse transcriptase-polymerase chain reaction (RT-PCR), with primers selected from the published human Ley I-L sequence. Normal and neoplastic breast tissue and fetal membranes with adhering decidua did not express the gene. The overall sequence of the trophoblast gene was in agreement with that reported with minor changes only in the putative connecting peptide, confirmed by restricted enzyme digestion. A 290 bp RT-PCR product was cloned and used as a cDNA probe in Northern analyses; hybridization was readily shown with cyclic corpora lutea but not with other tissues. The broader spectrum of the expression of this...
Gene expression during development of Blastocladiella emersonii

Abstract To evaluate gene expression during sporulation and early development of the aquatic fungus Blastocladiella emersonii, the nucleotide sequence complexity of the polysomal RNA has been measured at different stages. To assess the effect of medium composition on gene expression, similar experiments were completed during early development in a range of simple to complex media. The polysomal RNA sequence complexity was measured by hybridization with single-copy tracer DNA and with a complex class-enriched cDNA fraction copied from the stored zoospore poly(A+)RNA. Forty-four to eighty-six percent (8.2 × 106 to 16 × 106 nucleotides) of the single-copy DNA sequence complexity was found on polysomes, depending upon the stage examined or the medium used, compared to 42.5% (8 × 106 nucleotides) in the stored RNA pool of zoospores. The highest levels of complexity occurred during the two periods of active differentiation, sporulation and germination. During starvation-induced sporulation, and average of 82% of the total asymmetrically transcribed complexity was expressed; half of this complexity was lost prior to the completion of zoospore differentiation and was missing from the zoospore-stored RNA pool. During the first 30 min of zoospore germination the level of sequence complexity increased by 46 to 66% over the zoospore level, depending upon the medium used. The polysomal RNA complexity then decreased by a nearly equal amount between 30 and 60 min when the cells entered the growth phase. An inverse relationship was found between the richness of the medium and the level of sequence complexity found on polysomes. The data indicate that sequences representative of most of the zoospore-stored poly(A+)RNA were expressed at all other stages and maintained by turnover and resynthesis. In addition, significant numbers of new sequences were also expressed, particularly during stages of active differentiation. Cells that germinated and completed early development in an inorganic starvation medium showed a marked loss of the middle and high abundance classes of poly(A+)RNA and slight enrichment for the low abundance class.
Modes of Interannual Tropical Ocean–Atmosphere Interaction—a Unified View. Part I: Numerical Results

Abstract Coupled ocean-atmosphere models exhibit a variety of forms of tropical interannual variability that may be understood as different flow regimes of the coupled system. The parameter dependence of the primary bifurcation is examined in a “stripped-down” version of the Zebiak and Cane model using the equatorial band approximation for the sea surface temperature (SST) equation as by Neelin. In Part I of this three-part series, numerical results are obtained for a conventional semispectral version; Parts II and III use an integral formulation to generate analytical results in simplifying limits. In the uncoupled case and in the fast-wave limit (where oceanic adjustment occurs fast compared to SST time scales), distinct sets of modes occur that are primarily related to the time scales of SST change (SST modes) and of oceanic adjustment (ocean-dynamics modes). Elsewhere in the parameter space, the leading modes are best characterized as mixed SST/ocean-dynamics modes; in particular, the continuous surfa...
Gender and seasonally related differences in myocardial recovery and susceptibility to sotalol-induced arrhythmias in isolated rabbit hearts.

Gender and Seasonal Differences in Rabbit Hearts. Introduction: Gender differences and seasonal variations in cardiac electrophysiology and susceptibility to arrhythmias have been described clinically. The present study was undertaken to determine if there are similar gender and seasonally related differences in the electrophysiology of the rabbit heart. Methods and Results: We analyzed epicardial electrograms, left ventricular endocardial monophasic action potentials (MAPs), and simulated X and Y lead ECGs from 145 isolated rabbit hearts studied over a period of 41 months. Hearts from males had seasonal increases in the duration of myocardial recovery. During the months of June to September compared with October to January and February to May, epicardial activation-recovery intervals (231.6 ± 23.4 vs 215.6 ± 19.2 and 213.5 ± 18.8 msec, P = 0.003), MAP durations (256.5 ± 25.4 vs 237.0 ± 19.6 and 230.7 ± 26.4 msec, P < 0.001), and QT intervals (278.3 ± 25.6 vs 267.3 ± 11.8 and 261.3 ± 13.0 msec, P = 0.03) were longer. Overall, hearts from females had shorter QT intervals than males (257.7 ± 15.7 vs 270.1 ± 20.3 msec, P < 0.001), and this difference was reflected in their shorter epicardial activationrecovery intervals and MAP durations. However, hearts from females showed a greater prolongation of epicardial recovery (P = 0.007) and greater incidence of arrhythmias (P < 0.001) with sotalol than males. Also, the incidence of arrhythmias was greater in the winter months October to May (P < 0.001). Conclusion: The isolated rabbit heart provides a spontaneous model of gender and seasonally related differences in cardiac electrophysiology and arrhythmia susceptibility. These differences may be related to variation in the expression of or regulation of the membrane ion channels mediating repolarization.
Expression of cholinergic markers in transplants of immature mouse neocortex into adult mouse parietal cortex

Cerebral cortex of embryonic and newborn mouse was removed and transplanted into adult mouse neocortex to investigate whether the development of cholinergic markers would proceed normally after transplantation. It is shown that both AChE and muscarinic receptors developed in transplanted mouse neocortex. However, while muscarinic receptor binding increased to adult levels in transplants from both pre- and postnatal donors AChE staining intensity only achieved adult levels in tissue from postnatal donors. These results are in accordance with the normal developmental time course of the two different cholinergic markers, since muscarinic receptors appear prenatally in cortex while AChE becomes histochemically detectable after birth. These data suggest that the prenatal donor tissue, unlike the postnatal transplants, lacks an environmental signal for the appearance of AChE stained elements, that is, presumably host AChE fiber ingrowth. Transplantation of immature donor CNS tissue into adult host thus appears to be a useful paradigm to study the regulation of differentiation processes.
Mechanism of interferon action Interferon-mediated inhibition of reovirus mRNA translation in the absence of dettectable mRNA degradation but in the presence of protein phosphorylation

Abstract The effect of treating mouse fibroblast L cells with interferon on the ability of nonpreincubated and micrococcal nuclease-treated extracts prepared from them to catalyze reovirus messenger RNA translation, protein phosphorylation, and messenger RNA degradation was investigated both in the presence and the absence of exogenously added double-stranded RNA (dsRNA) and transfer RNA (tRNA). The following results were obtained: (1) Phosphorylation of ribosome-associated protein P, and protein synthesis initiation factor eIF-2α was enhanced in both nonpreincubated and micrococcal nuclease-treated extracts prepared from interferon-treated cells. The enhancement in phosphorylation was dependent upon the presence of reovirus dsRNA, although the apparent dsRNA requirement could also be fulfilled by reovirus mRNA at concentrations of mRNA typical of those used in cell-free protein synthesizing systems. (2) By contrast, the degradation of reovirus [ 3 H]mRNA was enhanced in extracts prepared from interferon-treated cells when nonpreincubated, but not when micrococcal nuclease-treated and supplemented with ethyleneglycol-bis(β-aminoethyl ether)- N , N ′-tetraacetic acid (EGTSA) and 2′-deoxythymidine-3′,5′-diphosphate (pTp). The enhancement in degradation observed in nonpreincubated extracts lacking EGTA and pTp was dependent upon the presence of dsRNA and the absence of tRNA; enhanced dsRNA-dependent degradation was not detectable in the presence of tRNA. The limited degradation of reovirus [ 3 H]mRNA, in both the presence and the absence of dsRNA and tRNA, was comparable in EGTA- and pTp-supplemented micrococcal nuclease-treated extracts prepared from either interferon-treated or untreated cells. The addition of 2′,5′-oligoadenylate enhanced degradation in nonpreincubated extracts but not in EGTA- and pTp-supplemented micrococcal nuclease-treated extracts (3) Reovirus mRNA was translated poorly by interferon-treated as compared to untreated systems in both the nonpreincubated and the micrococcal nuclease-treated extracts in the absence of reovirus dsRNA. The presence of dsRNA further decreased the translation by interferon-treated systems. The efficiency of endogenous cellular mRNA translation by untreated as compared to interferon-treated systems was comparable in nonpreincubated extracts, both in the presence and absence of dsRNA. The addition of mouse ascites tRNA stimulated translation in both untreated and interferon-treated systems, both in nonpreincubated and micrococcal nuclease-treated extracts. These results suggest that the translation of reovirus mRNA in interferon-treated systems is inhibited both in the presence and absence of interferon-mediated mRNA degradation, and that protein phosphorylation may play a primary role in regulating translation in interferon-treated cells.
Epidemiology of norovirus gastroenteritis outbreaks in two primary schools in a city in eastern China

We describe the epidemiology of 2 outbreaks of norovirus (GII) gastroenteritis in elementary schools in a city in eastern China using data from field investigations, pathogen testing, and face-to-face interviews. The transmission shows a point source type. In a case-control study, we identified airborne and person-to-person transmission as the source of the outbreaks.
Preferential alkylation by 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) of guanines with guanines as neighboring bases in DNA.

Abstract The base sequence of DNA has been shown to influence the kinds and amounts of alkylation of purine bases by N-methyl-N-nitrosourea [W.T. Briscoe and L-E. Cotter, Chem. Biol. Interact. 56, 321 (1985)]. In the present study, the alkylation of DNA polymers of denned sequence by 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) has been investigated. The assay involved treating poly (dG)-poly(dC), poly(dG-dC)-poly(dG-dC), poly(dA-dC)-poly(dG-dT), poly(dA-dG)-poly(dC-dT), and calf thymus DNA with BCNU, followed by hydrolysis to release the modified purine bases and separation and quantitation of these by HPLC. Analysis of the results revealed that there was a 24-fold increase of 7-(β-hydroxyethyl)guanine (HOEtG) in poly(dG)-poly(dC) relative to poly(dAdG)· poly(dC-dT). There was also a 3-fold increase in HOEtG in poly(dG-dC)· poly(dG-dC), poly(dAdC)·poly(dG-dT) and calf thymus DNA relative to poly(dA-dG)· poly(dC-dT). A 2- to 4-fold increase of 7(β-aminoethyl)guanine (AmEtG) was observed in poly(dG-dC)· poly(dG-dC) relative to the other polymers tested. This study has determined that guanines in certain base sequences in polydeoxy-ribonucleotides are more susceptible to BCNU alkylation at the N-7 position than guanines in other sequences.
Hypersonic flowfield effects on small delta- tail surfaces.

A multilayered model for the structure of the hypersonic flowfield about a cone cylinder at cross-flow Mach numbers (Mc = M sinoj) up to 3.5, is deduced empirically from wind-tunnel force measurements on a delta-tail surface at freestream Mach numbers (M) of 4.4 and 7.7, from schlieren photographs, and from cone flowfield surveys reported in the literature. Based on this model, a shock-expansion type of theory is developed, then used to calculate forces on the tail surface which agree with wind-tunnel data for various locations around the body circumference and angles of attack (a:) up to 25°. It appears that at hypersonic Mach numbers, body shock-wave effects require that two inviscid flow regimes, one at high and another at low angles of attack, be distinguished.
The interaction of an isolated sprinkler spray and a two-layer compartment fire environment. phenomena and model simulations

Abstract A general description of the interaction of sprinklers and compartment-fire-generated smoke layers is presented. Various possible aspects of the interaction phenomena (upper-layer smoke entrainment into the sprinkler spray, momentum and mass exchange between droplets and entrained gas, gas cooling by evaporation, buoyancy effects, and others) are discussed in the context of a two-layer-type description of the fire environment. The inputs and outputs for a mathematical submodel which simulates the phenomena are discussed. The submodel is suitable for general use in any two-layer, zone-type compartment fire model. Results from exercising the submodel are presented. These example calculations simulate the interaction between the spray of a real sprinkler device and a range of two-layer fire environments. The calculations reveal an important generic interaction phenomenon, namely, an abrupt and large change in the growth rate of the upper layer that would accompany an increase in upper-layer thickness beyond a critical thickness (for a given upper-layer temperature) or an increase in upper-layer temperature beyond a critical temperature (for a given upper-layer thickness). Exceeding these critical values would lead to a very large rate of growth of upper layer thickness, a growth that could lead to rapid and complete smoke filling of even the largest compartments of fire origin.
The Effect of Marked Inhibition of Sebum Production with 13Cis-retinoic Acid on Skin Surface Lipid Composition

Sebum production and skin surface lipid composition have been measured during the oral treatment with 13cis-retinoic acid of a group of patients with severe cystic acne. Two hundred and thirty-eight paired samples have been analyzed and compared. A marked, drug-induced decrease in sebum production was accompanied by a decrease in the concentration of wax esters, a slight decrease in the squalene concentration and in increase in the cholesterol concentration in the skin surface lipids. These changes were consonant with changes in the relative contributions of sebum and epidermal lipid to the surface film, except that at very low levels of sebum production there might be preferential preservation of squalene synthesis.
Relative bioavailability of a novel sustained-release acetaminophen molded tablet☆

Abstract An experimental easily swallowable oral sustained-release dosage form of acetaminophen (APAP) that can be administered to patients every 12 hours was formulated and evaluated in 8 healthy, adult volunteers. The test product was compared to a well-characterized, commercially available immediate-release acetaminophen caplet. Multiple doses of these two products were administered to 8 healthy human subjects in a two-way cross-over design. Saliva samples were collected over a period of 24–48 h depending upon the administered treatment. The time course of acetaminophen concentrations in saliva was analyzed using non-compartmental methods. Results indicate that it is possible to maintain the desired therapeutic concentration over a 12-h dosing interval using the molded tablet dosage form.
Toward detecting the formation of a single helical turn by 2D IR cross peaks between the amide-I and -II modes.

We have combined two-dimensional infrared (2D IR) spectroscopy and isotope substitutions to reveal the vibrational couplings between a pair of amide-I and -II modes that are several residues away but directly connected through a hydrogen bond in a helical peptide. This strategy is demonstrated on a 310-helical hexapeptide, Z-Aib-l-Leu-(Aib)2-Gly-Aib-OtBu, and its 13C═18O-Leu monolabeled and 13C═18O-Leu/15N-Gly bis-labeled isotopomers in CDCl3. The isotope-dependent amide-I/II cross peaks clearly show that the second and fourth peptide linkages are vibrationally coupled as they are in proximity, forming a 310-helical turn. The experimental spectra are compared to simulations based on a vibrational exciton Hamiltonian model that fully takes into account the amide-I and -II modes. The amide-II local mode frequency is evaluated by a new model based on the effects of hydrogen-bond geometry and sites. Ab initio nearest-neighbor coupling maps of the amide-I/I, -I/II, -II/I and -II/II modes are generated by isoto...
Interaction of moving interfaces with obstacles

Abstract The interaction of a moving interface with a single obstacle, a lattice and a random array of obstacles in d = 2 dimensions is investigated. The time to overcome an obstacle, conditions for pinning and the formation of islands by surrounding obstacles are considered.
Market Demand for Special Education Faculty

Since 1988, researchers have monitored the extent and severity of the chronic special education (SE) faculty shortage. The present study sought to add to this knowledge base by (a) gathering data o...
Rayleigh Task Performance as a Method to Evaluate Image Reconstruction Algorithms

We evaluate several tomographic reconstruction algorithms on the basis of how well one can perform the Rayleigh discrimination task using the reconstructed images. The Rayleigh task is defined here as deciding whether a perceived object is either a pair of neighboring points or a line, both convolved with a 2D Gaussian. The method of evaluation is based on the results of a numerical testing procedure in which the stated discrimination task is carried out on reconstructions of a randomly generated sequence of images. The ability to perform the Rayleigh task is summarized in terms of a discriminability index that is derived from the area under the receiver-operating characteristic (ROC) curve. Reconstruction algorithms employing a nonnegativity constraint are compared, including maximum a posteriori (MAP) estimation based on the Bayesian method with entropy and Gaussian priors as well as the additive and multiplicative versions of the algebraic reconstruction technique (ART and MART). The performance of all four algorithms tested is found to be similar for complete noisy data. However, for sparse noiseless data, the MAP algorithm based on the Gaussian prior does not perform as well as the others.
Using the affective reasoner to support social simulations

This paper is in two parts. In the first part, the outline of an emotion reasoning architecture, embodied in a simulation program called the Affective Reasoner, is presented, and a rudimentary personality representation for simulated agents is introduced. In the second part, an exercise is reviewed in which the Affective Reasoner is given the task of representing agents with different personality types in such a way as to allow the user to engage in a simulated interaction with them. Representational issues pertaining to the unique appraisal and behavioral styles of the different personality types are addressed. Conclusions are drawn about the usefulness of the Affective Reasoner in such a paradigm.
ZRT/IRT-like Protein 14 (ZIP14) Promotes the Cellular Assimilation of Iron from Transferrin

ZIP14 is a transmembrane metal ion transporter that is abundantly expressed in the liver, heart, and pancreas. Previous studies of HEK 293 cells and the hepatocyte cell lines AML12 and HepG2 established that ZIP14 mediates the uptake of non-transferrin-bound iron, a form of iron that appears in the plasma during pathologic iron overload. In this study we investigated the role of ZIP14 in the cellular assimilation of iron from transferrin, the circulating plasma protein that normally delivers iron to cells by receptor-mediated endocytosis. We also determined the subcellular localization of ZIP14 in HepG2 cells. We found that overexpression of ZIP14 in HEK 293T cells increased the assimilation of iron from transferrin without increasing levels of transferrin receptor 1 or the uptake of transferrin. To allow for highly specific and sensitive detection of endogenous ZIP14 in HepG2 cells, we used a targeted knock-in approach to generate a cell line expressing a FLAG-tagged ZIP14 allele. Confocal microscopic analysis of these cells detected ZIP14 at the plasma membrane and in endosomes containing internalized transferrin. HepG2 cells in which endogenous ZIP14 was suppressed by siRNA assimilated 50% less iron from transferrin compared with controls. The uptake of transferrin, however, was unaffected. We also found that ZIP14 can mediate the transport of iron at pH 6.5, the pH at which iron dissociates from transferrin within the endosome. These results suggest that endosomal ZIP14 participates in the cellular assimilation of iron from transferrin, thus identifying a potentially new role for ZIP14 in iron metabolism.
Nucleotide sequence of the mannitol (mtl) operon in Escherichia coli

Summary The nucleotide sequence of the known portions of the mannitol operon in Escherichia coli (mtlOPAD) has been determined. Both the operator-promoter region and the intercistronic region between the mtlA and mtID genes (encoding the mannitol-specific Enzyme II of the phosphotransferase system and mannitol–1- phosphate dehydrogenase, respectively) show parallels with corresponding regions of the glucitol (gut) operon, but neither the mtlA nor the mtlD gene products show obvious homology with the corresponding gene products of the glucitol operon. Five potential cyclic AMP receptor protein binding sites were identified in the mtlOP region, all showing near identity with the consensus sequence. Four regions of dyad symmetry (four to seven bases in length), serving as potential repressor binding sites, overlap with the potential cyclic AMP receptor protein binding sites. Repetitive extragenic pallndromic (REP) sequences, forming stem-loop structures in the intercistronic region between mtlA and mtlD and following the mtlD gene were identified. Probable terminator sequences were not found in any of these three regulatory regions. Mannitol–1-phosphate dehydrogenase exhibits two overlapping, potential NAD+ binding sites near the W-terminus of the protein. Computer techniques were used to analyse the mtlD gene and its product.