cssi/SciSciGPT-SciSciNet huggingface dataset:
Central serotonergic uptake mechanisms in hypertensive rats: effects of clonidine and centhaquin

Abstract The binding of a highly specific ligand for serotonin (5-HT) uptake sites, [ 3 H]paroxetine, was studied in brain regions of normotensive. Wistar-Kyoto rats (WKY) and spontaneous hypertensive rats (SHR). [ 3 H]Paroxetine bound to a single ,high affinity binding site in the brain. In midbrain, the density (B max values) of [ 3 H]paroxetine binding were significantly reduced (27.16%) in SHR as compared to WKY. The affinity (K d values) were found to be similar in SHR and WKY. The K d and B max values of [ 3 H]paroxetine binding were found to be similar in spinal cord, pons and medulla and cerebral cortex of WKY and SHR. The effect of centrally acting hypotensive agents, clonidine and centhaquin, on [ 3 H]paroxetine binding was also determined and compared with imipramine, a known 5-HT uptake inhibitor. Clonidine did not displace [ 3 H]paroxetine binding at any concentration (10 −4 to 10 −7 M). On the other hand, centhaquin, which produces hypotension similar to clonidine, could displace [ 3 H]paroxetine binding in a concentration dependent manner. In cerebral cortex and brainstem (midbrain, pons and medulla) membranes, the IC 50 values of imipramine and centhaquin for [ 3 H]paroxetine binding were found to be similar in WKY and SHR. The IC 50 of centhaquin in displacing paroxetine from 5-HT uptake sites was 1- times lower in the cerebral cortex and 4 times lower in the brainstem membranes when compared to imipramine. Clonidine had no effect on 5-HT uptake sites. The results indicate that (1) the density of 5-HT uptake sites is reduced in the midbrain of hypertensive rats, and (2) centhaquin, a centrally acting hypotensive agent, acts on 5-HT transporter sites. These findings suggest that 5-HT uptake mechanisms may play a role in hypertension.
Preliminary Studies of Artificial Spawning of Channel Catfish as Male-Female Pairs or All-Female Groups in Recirculating Systems

Abstract— Channel catfish Icralurus punctatus are commonly spawned for research purposes by pairing of a hormonally treated female with a male in flow-through aquaria. A technique that allows hormonal induction of ovulation in females without pairing would accelerate genetic improvement and production of hybrid catfish. Over a 3-yr period (1994, 1995, and 1996) we conducted a series of trials to demonstrate the potential for artificial spawning in recirculating systems, and in 1996 we included trials with grouped females in addition to male-female pairs. Females were induced to spawn with injection of synthetic leuteinizing hormone-releasing hormone, and those that ovulated were stripped and the eggs were artificially fertilized. During 1994 and 1995, all fish were spawned by pairing, and in 1996, half of the females were spawned by pairing and half were grouped in tanks without males. Spawning success (percent of females that produced eggs), latency (time between injection and ovulation), and percent fertilization were observed for the paired and grouped trials. Spawning success was 36% in 1994 (N= 36). 22% in 1995 (N= 54). 41% in 1996 (N= 27). and 58% for grouped females (N= 26). The latency period was 113 ± 69 h in 1994, 109 ± 57 h in 1995, 44 ± 8 h in 1996, and 50 ± 9 h for grouped females. Percent fertilization was 16 ± 26% for eggs stripped in 1994, 72 ± 25% in 1995, 43 ± 20% in 1996, and 16 ± 37% for grouped females. In 1995, water quality problems were associated with high mortality of females (24 of 44 females; 4 of 44 males). The metabolic demands of final oocyte maturation in combination with methemoglobinemia caused by high nitrite levels could account for the increased vulnerability of females. These trials indicate that with adequate biofiltration, artificial spawning is possible in recirculating systems and with females grouped rather than paired. Further research on hormone dosage and timing of egg stripping will increase the utility of grouped spawning of channel catfish.
Absorption and distribution of Cr51 in the albino rat

Orally administered Na2Cr51O4 was absorbed to the extent of about 6% in fasted rats and about 3% in nonfasted rats as judged by the excretion of chromium in the urine. In both fasted and nonfasted animals hexavalent chromium was absorbed to a much greater extent than trivalent chromium. Considerable reduction of chromate to the trivalent state occurred in the stomach, and to a lesser extent in the intestines. After feeding radioactive chromate, the liver showed a maximal uptake after 1 day of about 1% of the administered dose whereas kidney and blood contained 0.1-0.2%. These quantities decreased over a 2-week period. Chromium absorbed by the spleen appeared to be bound more tightly than in other tissues studied.
Temporal reference in Paraguayan Guaraní, a tenseless language

This paper contributes data from Paraguayan Guarani (Tupi-Guarani) to the discussion of how temporal reference is determined in tenseless languages. The empirical focus of this study is on finite clauses headed by verbs inflected only for person/number information, which are compatible only with non-future temporal reference in most matrix clause contexts. The paper first explores the possibility of accounting for the temporal reference of such clauses with a phonologically empty non-future tense morpheme, along the lines of Matthewson’s (Linguist Philos 29:673–713, 2006) analysis of a similar phenomenon in St’at’imcets (Salish). This analysis is then contrasted with one according to which temporal reference is not constrained by tense in Paraguayan Guarani, but only by context and temporal adverbials. A comparison of the two analyses, both of which are couched in a dynamic semantic framework, suggests empirical and theoretical advantages of the tenseless analysis over the tensed one. The paper concludes with a discussion of cross-linguistic variation of temporal reference in tensed and tenseless languages.
Avian immunology: From Fundamental Immune Mechanisms to the Integrative Management of Poultry

Abstract INTRODUCTION The papers in this section represent the proceedings of the Symposium, “Current Advances in Avian Immunology” held preceding the 1993 Poultry Science Association Meeting. The symposium papers are initiated by contributions from two keynote immunologists, Noel Rose and Bruce Glick. Subsequent contributions follow a progression in which current concepts regarding avian immune mechanisms are first detailed by immune cell type. This is followed by consideration of interactions between the avian immune system and other genetic or physiological factors, including the soluble mediators for these interactions. Finally, a discussion of immune-environment interactions leads into presentations describing current and future strategies for immune management of poultry. The breadth of scope among these papers reflects the current status of avian immunology: namely, that the information base for the avian immune system has reached a sufficiently significant level to consider the application of integrated systems of immune management for poultry. Both the understanding …
Ensemble methods with simple features for document zone classification

Document layout analysis is of fundamental importance for document image understanding and information retrieval. It requires the identification of blocks extracted from a document image via features extraction and block classification. In this paper, we focus on the classification of the extracted blocks into five classes: text (machine printed), handwriting, graphics, images, and noise. We propose a new set of features for efficient classifications of these blocks. We present a comparative evaluation of three ensemble based classification algorithms (boosting, bagging, and combined model trees) in addition to other known learning algorithms. Experimental results are demonstrated for a set of 36503 zones extracted from 416 document images which were randomly selected from the tobacco legacy document collection. The results obtained verify the robustness and effectiveness of the proposed set of features in comparison to the commonly used Ocropus recognition features. When used in conjunction with the Ocropus feature set, we further improve the performance of the block classification system to obtain a classification accuracy of 99.21%.
Mammalian pitrilysin: substrate specificity and mitochondrial targeting.

The substrate specificity of the mitochondrial metallopeptidase proteinase 1 (MP1) was investigated and its mitochondrial targeting signal identified. The substrate specificity of MP1 was examined with physiological peptides as substrates. Although the enzyme exhibits broad substrate specificity, there is a trend for peptides containing 13 or more residues to exhibit Km values of 2 μM or less. Three of four peptides containing 11 or fewer residues exhibited Km values above 10 μM. Similarly, peptides containing 13 or more residues exhibited kcat values below 10 min−1, while three of four peptides containing 11 or fewer residues exhibited kcat values above 30 min−1. Many of the peptide cleavage sites of MP1 resemble that of the mitochondrial processing protease (MPP); however, MP1 does not process the precursor form of citrate synthase. The enzyme, however, does cleave the released prepeptide from precitrate synthase. A mitochondria localization was shown in MP1 transfected NT2 and HepG2 cells. Deletion of ...
Effects of stratification on data mining in the US Vaccine Adverse Event Reporting System (VAERS).

Background: Vaccines are administered differentially according to age and sex, and disease patterns also vary among people of different age and sex groups. Estimates of disproportionality should be calculated based on comparisons of groups that have a similar likelihood of receiving similar vaccines and experiencing similar adverse events, to prevent false disproportionality from occurring. Stratified empirical Bayesian (EB) methods have been compared with crude, but not stratified, proportional reporting ratios (PRRs) in their performance on adverse event data. Objectives: (i) to implement stratification of PRR; (ii) to quantify and compare vaccine-event pairs that are highlighted by PRR and EB05 (the lower bound of the 90% CI of the EB geometric mean), for both crude and stratified; and (iii) to evaluate the effects of stratification by age and sex, in identifying adverse events that are accepted to be caused by vaccines. Methods: We applied EB and PRR data mining methods to data from the US Vaccine Adverse Event Reporting System (VAERS). We stratified PRR and EB05 by age and sex. To study the effects of stratification, we compared the crude PRR and stratified PRR. We also assessed the crude EB05 and stratified EB05, and then compared the effects of stratification on EB05 and PRR. Results: Stratification not only changed the number of vaccine-event pairs that were highlighted, but also changed which pairs were highlighted. There were 283 vaccine-event pairs that were highlighted by the crude EB05, but not the stratified; 12 that were highlighted by the stratified EB05, but not the crude; and 162 that were highlighted by both. Similarly, there were 701 vaccine-event pairs that were highlighted by the crude PRR, but not the stratified; 139 that were highlighted by the stratified PRR, but not the crude; and 895 that were highlighted by both. There were 1466 vaccine-event pairs in which the effect of stratification was different for EB05 and PRR. Conclusion: To our knowledge, this is the first published analysis using stratified PRRs. In this analysis of passive surveillance data, stratification revealed and reduced confounding in EB and PRR, and also unmasked some vaccine-event pairs that the crude values did not highlight. Stratification should be applied if confounding is suspected. By decreasing the total number of highlighted vaccine-event pairs, stratification is likely to increase efficiency and therefore might reduce workload.
Effects of metronidazole on periodontal treatment needs

Periodontitis, a common cause of tooth loss in adult populations, is an inflammatory response to the overgrowth of anaerobic organisms such as spirochetes and bacteroides and, in some cases, micro-aerophilic organisms in the subgingival plaque. In the present investigation, using a double-blind clinical design, we sought to determine whether 1 week of metronidazole treatment plus debridement of the tooth surfaces was superior to 1 week of placebo treatment plus debridement (positive control) in reducing the subsequent amount of periodontal surgery given to the patients. Thirty-nine patients were randomly assigned to either the metronidazole or placebo (positive control) groups. All patients were given the necessary scaling and root planing and were unsupervised in their usage of the medication. After the completion of this treatment, they were reexamined and it was found that the metronidazole regimen caused a significant reduction in surgical needs of about 5 teeth per patient compared to the positive control (difference before and after treatment 8.3 +/- 6.8 teeth metronidazole versus 2.9 +/- 4.8 positive control, P = 0.007). The difference between groups was maintained during the 2 to 3 years' recall period. Metronidazole had a significant effect on the site specific reduction of spirochetes: 90% of the sites in the metronidazole group versus 64% in the positive-control group had a decrease in the percentage of spirochetes (P less than 0.05). We conclude that systemic metronidazole given 250 mg tid for 7 days in conjunction with debridement of the tooth surfaces can significantly reduce the need for periodontal surgery compared to the standard regimen which included only debridement.
Improved Hatchability of Turkey Eggs at High Altitudes Due to Added Oxygen and Increased Incubation Temperature

Abstract Turkey egg hatchability at high altitudes was examined at two different oxygen tensions and two incubation temperatures. Incubating turkey eggs in a 149-torr oxygen environment at 37.7 C gave significantly better hatchability than a 109-torr oxygen environment at 37.5 C. Embryonic mortality data indicated that the higher incubation temperature in combination with increased oxygen tension decreased embryonic mortality during the 3rd and 4th wk of incubation and resulted in higher hatchability. The data suggest that hatchery managers at high altitudes should supplement with oxygen and incubate turkey eggs at higher temperatures than employed at lower altitudes.
Unmarked gene deletion mutagenesis of gtfB and gtfC in Streptococcus mutans using a targeted hit-and-run strategy with a thermosensitive plasmid

Unmarked gene deletion of the Streptococcus mutans gtfB-gtfC locus was achieved using a thermosensitive plasmid. DNA fragments flanking the locus were amplified by polymerase chain reaction and jointly ligated into pG+host5, which was transformed into S. mutans at 37 degrees C to facilitate integration. A transformant was then grown at 28 degrees C for 60 generations without antibiotics to facilitate excision. Antibiotic sensitive clones appeared at a frequency of about 99% and were analyzed for deletions of gtfB, gtfC and a part of mbrA by the lack of insoluble glucan synthesis, sensitivity to bacitracin, and polymerase chain reaction. Targeted gene deletions occurred at a frequency of 2.5%.
Metabolites Associated with Adaptation of Microorganisms to an Acidophilic, Metal-Rich Environment Identified by Stable-Isotope-Enabled Metabolomics

ABSTRACT Microorganisms grow under a remarkable range of extreme conditions. Environmental transcriptomic and proteomic studies have highlighted metabolic pathways active in extremophilic communities. However, metabolites directly linked to their physiology are less well defined because metabolomics methods lag behind other omics technologies due to a wide range of experimental complexities often associated with the environmental matrix. We identified key metabolites associated with acidophilic and metal-tolerant microorganisms using stable isotope labeling coupled with untargeted, high-resolution mass spectrometry. We observed >3,500 metabolic features in biofilms growing in pH ~0.9 acid mine drainage solutions containing millimolar concentrations of iron, sulfate, zinc, copper, and arsenic. Stable isotope labeling improved chemical formula prediction by >50% for larger metabolites (>250 atomic mass units), many of which were unrepresented in metabolic databases and may represent novel compounds. Taurine and hydroxyectoine were identified and likely provide protection from osmotic stress in the biofilms. Community genomic, transcriptomic, and proteomic data implicate fungi in taurine metabolism. Leptospirillum group II bacteria decrease production of ectoine and hydroxyectoine as biofilms mature, suggesting that biofilm structure provides some resistance to high metal and proton concentrations. The combination of taurine, ectoine, and hydroxyectoine may also constitute a sulfur, nitrogen, and carbon currency in the communities. IMPORTANCE Microbial communities are central to many critical global processes and yet remain enigmatic largely due to their complex and distributed metabolic interactions. Metabolomics has the possibility of providing mechanistic insights into the function and ecology of microbial communities. However, our limited knowledge of microbial metabolites, the difficulty of identifying metabolites from complex samples, and the inability to link metabolites directly to community members have proven to be major limitations in developing advances in systems interactions. Here, we show that combining stable-isotope-enabled metabolomics with genomics, transcriptomics, and proteomics can illuminate the ecology of microorganisms at the community scale.
Writing motivation of students with language impairments

This study compared the writing motivation of students with language impairments (LI) and their typically developing (TD) peers. For the study 272 students (33 students with language impairments, 242 TD peers) aged 8–10 years, in 11 elementary schools, were sampled. The two groups completed self-report measures of writing motivation and 20 grade-appropriate spelling words from a standardized measure. Multiple regression analyses were used to examine the hypothesis that perceived writing competence – a self-evaluative judgment of writing competence – mediates the relationship between LI status (LI or TD) and intrinsic forms of writing motivation. Statistical analyses indicated that (1) students with specific language impairments reported lower levels of perceived writing competence and intrinsic writing motivation; (2) LI status was a significant predictor of perceived competence after spelling, grade and gender were controlled; and (3) when spelling, grade and gender were controlled, perceived writing com...
Analysis of the convergence behavior of the complex Gaussian kernel LMS algorithm

Kernel-based adaptive filters present a new opportunity to re-cast nonlinear optimization problems over a Reproducing Kernel Hilbert Space (RKHS), transforming the nonlinear task to linear, where easier and well-known methods may be used. The approach can be seen to yield solutions suitable for sparse adaptive filtering. The new Complex Kernel Least Mean Square algorithm (CKLMS), derived by Bouboulis and Theodoridis, allows kernel-based online adaptive filtering for complex data. Here we report our results on the convergence of CKLMS with the complexified form of the Gaussian kernel. The analysis performed is based on a recent study of the Kernel LMS from Parreira et al. The analysis is used to generate theory-predicted MSE curves which consider the circularity/non-circularity of complex input which to our knowledge has not been considered previously for online nonlinear learning. Simulations are used to verify the theoretical analysis results.
Current approaches in the treatment of chronic kidney disease mineral and bone disorder

Patients with chronic kidney disease (CKD) develop mineral and bone disorder (MBD), a common and important complication, as a result of impaired phosphorus excretion and reduced vitamin D activatio...
Structural characterization of SiO2-CsAlO2 and SiO2-RbAlO2 glasses

Glasses along the SiO2–CsAlO2 and SiO2–RbAlO2 joins were prepared by a sol–gel method and studied using 29Si and 27Al nuclear magnetic resonance and by infrared and Raman spectroscopy. The 29Si and 27Al chemical shifts follow the same trend with composition as found in previous studies, due to the formation of Q4(1Al) and Q4(2Al) species in the glass, consistent with Raman spectroscopy. The Raman spectra indicate a larger proportion of 3-membered (Si, Al)-containing rings than is present in other alkali aluminosilicate glasses with similar silica content. This effect occurs because the large alkali cations (Cs+, Rb+) require the formation of large cages in the glass structure, which in return requires the simultaneous formation of additional small rings.
The impact of single antimicrobial intervention treatment with cetylpyridinium chloride, trisodium phosphate, chlorine dioxide or lactic acid on ground beef lipid, instrumental color and sensory characteristics

Abstract The effects of antimicrobial agents on ground beef were evaluated to determine if instrumental color, sensory or odor characteristics were impacted. Trimmings were treated with 0.5% cetylpyridinium chloride (CPC), 200-ppm chlorine dioxide (CLO), 0.5% lactic acid (LA), 10% trisodium phosphate (TSP), or an untreated control (C). Ground beef made from trimmings with CLO and TSP were similar ( P > 0.05) in L ∗ values to the control; however, samples were redder ( a ∗ ; P P P >0.05) to the control in beef odor intensity until day 3 of display. Therefore, the use of antimicrobial agents on beef trimmings may not adversely affect, and may improve bulk ground beef color and odor characteristics.
Emerging tick-borne diseases

Ticks are capable of transmitting numerous pathogens to both humans and their pets. The risks of tick-borne disease risks vary geographically and are determined by the climate, environment, the presence of rodents and other mammal reservoirs, and the species of ticks parasitizing wild and domestic animals. Zoonoses such as Lyme borreliosis, tularemia, and tick-borne rickettsioses can emerge in previously nonendemic areas when circumstances favorable to their maintenance and transmission arise. Tick-borne zoonosis can be prevented by implementation and adoption of an integrated program to reduce the likelihood of tick bites on pets and their owners.
4663 Pancreatic sphincterotomy improves symptoms in patients with pancreatic sphincter hypertension persisting after biliary sphincterotomy.

BACKGROUND: PSH can persist after BSx. There is little information regarding the clinical symptom response to BSx and PSx in patients with PSH. AIM: Evaluate the effect of PSx on symptoms in patients with persistent PSH after prior BSx. METHODS: Patients with prior sphincter of Oddi dysfunction (SOD) treated initially with BSx and who had persistent PSH were analyzed. Clinical data were evaluated for the subsequent endoscopic therapy (if any). All patients were contacted by telephone to evaluate symptom response to their most recent endoscopic therapy. Manometry was performed with a standard perfused, aspirating catheter and SOD diagnosed if the mean pressure form two leads was ≥ 40 mmHg. Persistent PSH was documented by pancreatic manometry immediately after BSx and prior to PSx at a subsequent procedure. Patients who had normal pancreatic manometry were excluded from analysis. RESULTS: 42 patients (mean age 53 yrs, range 21-83 yrs , M:F=9/39) underwent isolated BSx in the setting of PSH. Of these 21 (50%) patients returned with persistent symptoms and underwent PSx. Patients were interviewed regarding symptom response at a mean of 39 months ( range 6.8-53months) after their most recent endoscopic intervention. Of the 21 patients who only had BSx as their most recent therapy (i.e. untreated PSH), 13 (62%) reported resolution of pain/symptoms, 6 (29%) reported improvement of symptoms and 2 (9%) reported no change in symptoms. Of the 21 patients who returned after BSx with persistent symptoms and who underwent PSx to treat PSH, 3 (14%) reported resolution of symptoms,11 (52%) reported improved symptoms, 6 (29%) reported no change and 1 (5%) reported worsening symptoms. After initial BSx, post-ERCP pancreatitis occurred in 4/21 (19%) patients who subsequently returned with symptoms, compared to 1/21 (5%) (NS) in patients who did not receive subsequent PSx. CONCLUSIONS: 1] Pancreatic sphincterotomy can improve symptoms in 66% of patients with prior biliary sphincterotomy but persistent PSH and symptoms. 2] However, a significant portion of patients (45%) with persistent PSH immediately after biliary sphincterotomy report symptom improvement without pancreatic sphincterotomy. This suggests that BSx alone may provide adequate symptom relief in some patients. Further study is needed to identify which patients with PSH would benefit from pancreatic sphincterotomy in addition to biliary sphincterotomy.
Using Random Walks for Question-focused Sentence Retrieval

We consider the problem of question-focused sentence retrieval from complex news articles describing multi-event stories published over time. Annotators generated a list of questions central to understanding each story in our corpus. Because of the dynamic nature of the stories, many questions are time-sensitive (e.g. "How many victims have been found?") Judges found sentences providing an answer to each question. To address the sentence retrieval problem, we apply a stochastic, graph-based method for comparing the relative importance of the textual units, which was previously used successfully for generic summarization. Currently, we present a topic-sensitive version of our method and hypothesize that it can outperform a competitive baseline, which compares the similarity of each sentence to the input question via IDF-weighted word overlap. In our experiments, the method achieves a TRDR score that is significantly higher than that of the baseline.
Sea level variations, global sedimentation rates and the hypsographic curve

Sea level changes during the Neozoic have been estimated by two different methods. The first involves measuring the amount of present-day land area which was flooded during the past, and using the present-day hypsographic curve to estimate the amount of sea level rise necessary to produce this flooding. The second involves the estimation of the changing volume of mid-oceanic ridges through time, and estimating sea level changes after having allowed for isostatic adjustment. A difference in sea level of 170 m is obtained from the two methods for the Cretaceous (80-100 m.y.B.P.). This is equivalent to a difference in continental flooding of 24 Mm 2, using the present-day hypsographic curve. We attempt to explain this difference firstly by allowing for the fact that the present-day ocean basins have more sediment in them than did the Cretaceous ocean basins. This produces a sea level change in the opposite direction to that produced by the reduction in mid-ocean ridge volume since the Cretaceous. Secondly, we suggest another large factor in producing the difference is that the present-day hypsographic curve is not the correct one to use when studying sea level stands in the Cretaceous. Present-day average continental heights are closely related to continental areas. Accepting this principle, if continents are joined together in the past, their average height must be greater, and so their hypsographic curve must be steeper. A given sea level rise would produce less continental flooding during times of continental aggregation than it would today.
Characterization of synthetic rabbit globin DNA.

Abstract Synthetic DNA (cDNA) complementary to purified mRNA has already proven to be a useful hybridization probe for the quantitation of specific genes and for the detection of specific mRNAs in eukaryotic organisms. In view of its central role in such studies, it seemed necessary to characterize further one such cDNA and to determine the value of established techniques for detecting DNA-RNA hybrids when cDNA is used as a probe. We, therefore, synthesized cDNA complementary to purified rabbit globin mRNA using avian myeloblastosis virus reverse transcriptase. Equilibrium centrifugation in cesium chloride and nearest-neighbor analysis show this cDNA to be heteropolymeric, with a G,C content of 46–48%. Its base composition and nearest-neighbor analysis reflect the expected high frequency of TpT doublets, but also a relatively high proportion of GpG doublets. The cDNA contains at least one T-rich region of sufficient length to form a hybrid with poly (A). Hybridization involving this region is not detected when S i nuclease is used to detect DNA-RNA hybrids. However, this interaction does affect results obtained using hydroxyapatite chromatography. Thus, rabbit globin cDNA exhibits stringent hybridization specificity when assayed using S 1 nuclease, annealing efficiently to rabbit globin mRNA, and not to ribosomal, transfer, or nonglobin mRNAs.
Toxicity of penicillin for the Syrian hamster.

SummaryA single injection of crystalline penicillin G potassium administered subcutaneously or intraperitoneally is toxic for hamsters in proportion to amount administered. Toxicity is of the delayed type, the vast majority of deaths occurring on 3rd, 4th and 5th days following injection. This parallels the reported experience with guinea pigs and is in contrast to Swiss mice who easily tolerate very large doses of this antibiotic. In the light of these findings, reevaluation of experimental data concerned with Syrian hamsters either treated with or injected with material sterilized with penicillin would seem to be indicated.
High temperature SrCe0.9Eu0.1O3-δ proton conducting membrane reactor for H2 production using the water-gas shift reaction

Abstract The water–gas shift (WGS) reaction is used to shift the CO/H2 ratio prior to Fischer–Tropsch synthesis and/or to increase H2 yield. A WGS membrane reactor was developed using a mixed protonic–electronic conducting SrCe0.9Eu0.1O3−δ membrane coated on a Ni–SrCeO3−δ support. The membrane reactor overcomes the thermodynamic equilibrium limitations. A 46% increase in CO conversion and total H2 yield was achieved at 900 °C under 3% CO and 6% H2O, resulting in a 92% single pass H2 production yield and 32% single pass yield of pure permeated H2.
Autoimmune Disease 2002: An Overview

Autoimmune disease includes a large spectrum of clinically distinct entities that share a common etiology, a misguided, self-directed immune response. Collectively, they are major contributors to morbidity and mortality. Normally, the body utilizes a number of strategies to avoid the pathologic consequences of autoimmune reactions, but these defenses may fail for a combination of hereditary and environmental factors. Infection has long been regarded as a common environmental trigger of autoimmune disease. Our laboratory has developed a mouse model of myocarditis induced by Coxsackievirus B3 infection and demonstrated some of the steps involved in the transition from an infection to an autoimmune disease. Such basic studies may suggest improved treatment or preventive measures for this group of diseases.
Bremsstrahlung: an experimentalist’s personal perspective on the postmodern era

Abstract In this brief review I will discuss the recent experimental work on the doubly differential cross section, i.e. the photon energy and angular distribution, for electron bremsstrahlung from thin solid film and gas targets. Since the beginning of the modern era in the study of bremsstrahlung with the publication of the 1971 paper by Tseng and Pratt, Professor Pratt has been the dominant influence in bremsstrahlung research. Most, if not all, experimental research during the modern era has been motivated by the interest in comparing data with the theory of Pratt and his coworkers. As bremsstrahlung research has moved into its postmodern era, new experiments with increasing precision are concentrating on determining under what conditions ordinary bremsstrahlung theory needs to be supplemented by a contribution from polarization bremsstrahlung. Efforts to improve the comparison of thin-target experiment with theory have also led to new experimental and modeling work on bremsstrahlung from thick solid targets. Thick-target bremsstrahlung is interesting in its own right, but we also want to understand it better since it is the ever-present background in the thin-target experiments and the limiting factor in the effort to distinguish the polarization contribution to the total bremsstrahlung spectrum. Professor Pratt ushered in the modern era in bremsstrahlung research and has recently guided the transition into the postmodern era. It can be expected that he will continue to have a formative influence on the developments of bremsstrahlung research into the foreseeable future.
Radical Nephrectomy for pT1a Renal Masses May be Associated With Decreased Overall Survival Compared With Partial Nephrectomy

Purpose: We reviewed our surgical experience with small renal tumors, comparing overall survival in patients treated with radical and partial nephrectomy.Materials and Methods: Using our nephrectomy registry we identified patients with sporadic, unilateral, solitary and localized renal masses 4 cm or less who underwent radical or partial nephrectomy between 1989 and 2003. Patients with a solitary kidney or impaired renal function at presentation were excluded, leaving 648 available for analysis. Overall survival was estimated using the Kaplan-Meier method and associations with death were evaluated using Cox proportional hazards regression.Results: At last followup 146 patients had died of any cause and 502 were alive at a median of 7.1 years. Radical and partial nephrectomy was performed in 290 and 358 patients, respectively. In all patients radical nephrectomy was not significantly associated with death from any cause compared with partial nephrectomy (RR 1.12, p = 0.52). However, there was a significant...
Transient Q waves and reversible cardiac failure during myocardial ischemia: electrical and mechanical stunning of the heart.

Profound myocardial ischemia incapable of producing necrosis may alter myocardial biochemical processes, ultrastructure, and function for variable lengths of time after the ischemic process is reversed.’ Ordinarily, ECG manifestations of ischemia are limited to repolarization abnormalities. We describe here two patients who suffered from severe myocardial ischemia without infarction, which manifested as intractable angina and congestive heart failure due to advanced atherosclerotic disease in one patient and to vasospastic angina in the second. In both patients Q waves appeared and persisted for 36 and 48 hours, respectively. Subsequently Q waves disappeared after cessation of chest pain and reversal of ST-T changes. Myocardial necrosis was ruled out by serial enzyme determinations, normalization of ECGs, and normal ventricular wall motion on angiography. Exemplary patient 1. J.M., an 85-year-old woman with a 3-year history of stable angina pectoris, essential hypertension, and chronic bronchitis, was admitted to the hospital for bilateral cataract extraction under local anesthesia. Shortly after the operation she developed severe anterior chest pain. An ECG revealed ST elevation in leads V, to V, and atria1 fibrillation. She was transferred to the Coronary Care Unit. Physical examination revealed blood pressure of 140/‘/O mmHg, pulse 100 per minute, short apical systolic murmur, and scattered rales. Prolonged attacks of angina persisted. An ECG on admission to the Coronary Care Unit
Global Telecommunications Services: Strategies of Major Carriers

The globalization of telecommunications markets is of primary concern for todayâ€™s large telecommunications carriers. International business telecommunications is growing at a rate twice that of domestic traffic. Multi-national customers with offices around the world are demanding integrated solutions to their telecommunications needs. As telecommunication carriers respond to these customersâ€™ needs, the carriers are beginning to expand outside their national boundaries. This paper identifies the dominant telecommunications carriers and the major markets. Then, it describes the regulatory environment in the major markets of Japan, the United States and Western Europe and analyzes how the dominant carriers are implementing their globalization strategies. Based on the analysis, AT&T and British Telecom emerge as having the highest potential for continued globalization.
The role of the membrane in the inactivation of factor va by plasmin. Amino acid region 307-348 of factor V plays a critical role in factor Va cofactor function

Abstract The mechanism of inactivation of bovine factor Va by plasmin was studied in the presence and absence of phospholipid vesicles (PCPS vesicles). Following 60-min incubation with plasmin (4 nm) membrane-bound factor Va (400 nm) is completely inactive, whereas in the absence of phospholipid vesicles following a 1-h incubation period, the cofactor retains 90% of its initial cofactor activity. Amino acid sequencing of the fragments deriving from cleavage of factor Va by plasmin demonstrated that while both chains of factor Va are cleaved by plasmin, only cleavage of the heavy chain correlates with inactivation of the cofactor. In the presence of a membrane surface the heavy chain of the bovine cofactor is first cleaved at Arg348 to generate a fragment of M r 47,000 containing the NH2-terminal part of the cofactor (amino acid residues 1–348) and a M r 42,000 fragment (amino acid residues 349–713). This cleavage is associated with minimal loss in cofactor activity. Complete loss of activity of the membrane-bound cofactor coincides with three cleavages at the COOH-terminal portion of the M r 47,000 fragment: Lys309, Lys310, and Arg313. These cleavages result in the release of the COOH terminus of the molecule and the production of a M r 40,000 fragment containing the NH2-terminal portion of the factor Va molecule. Factor Va was treated with plasmin in the absence of phospholipid vesicles followed by the addition of PCPS vesicles and activated protein C (APC). A rapid inactivation of the cofactor was observed as a result of cleavage of the M r 47,000 fragment at Arg306 by APC and appearance of aM r 39,000 fragment. These data suggest a critical role of the amino acid sequence 307–348 of factor Va. A 42-amino acid peptide encompassing the region 307–348 of human factor Va (N42R) was found to be a good inhibitor of factor Va clotting activity with an IC50 of ∼1.3 μm. These data suggest that plasmin is a potent inactivator of factor Va and that region 307–348 of the cofactor plays a critical role in cofactor function and may be responsible for the interaction of the cofactor with factor Xa and/or prothrombin.
Influence of Nozzle Conditions and Discrete Forcing on Turbulent Planar Jets

Planar turbulent jets are of great interest in a broad range of engineering applications such as combustion, propulsion, and environmental flows. The influence of the turbulence intensity at the inflow and the shear-layer momentum thickness, as well as the effects of discrete forcing on the initial development of the jet, are studied computationally. The inflow fluctuation intensity and shear-layer momentum thickness have significant impact on the initial growth of the jet. Higher fluctuation intensity and thinner shear layers lead to more rapid growth of the jet with an asymptotic approach of the centerline turbulent kinetic energy to the self-similar values. The influence of the shear-layer thickness suggests a strong dependence of the initial growth on the shear-layer instabilities near the nozzle. Two-dimensional discrete forcing enhances the growth and two-dimensionality of the large-scale structures in the near field of the jet. However, significant three-dimensional small-scale structures coexist with the large-scale structures. The influence of the forcing is rapidly lost downstream as the large-scale structures break down
Self‐consistent Monte Carlo simulations of the electron and ion distributions of inhomogeneous liquid alkali metals. I. Longitudinal and transverse density distributions in the liquid–vapor interface of a one‐component system

Previous Monte Carlo simulations of the liquid–vapor interfaces of simple metals, which predict stratification of the liquid–vapor transition zone extending three atomic diameters into the bulk, suffer from a limitation arising from the use of a local electroneutrality approximation. This approximation is embodied in the assumption that, for the purpose of calculating the change in potential energy accompanying a change in configuration, there is exact coincidence of the electronic and ionic density profiles. In this paper we describe a generalized Monte Carlo simulation which avoids the local electroneutrality approximation by directly incorporating the Lang–Kohn treatment of the jellium‐vacuum interface into the simulations. We report the results of generalized Monte Carlo simulations of slabs of sodium at 100 and 200 °C and cesium at 100 °C. The new simulations predict structure in the liquid–vapor interface very similar to that predicted using the local‐electroneutrality approximation. The geometry of...
Towards the development of novel Trypanosoma brucei RNA editing ligase 1 inhibitors.

Background Trypanosoma brucei (T. brucei) is an infectious agent for which drug development has been largely neglected. We here use a recently developed computer program called AutoGrow to add interacting molecular fragments to S5, a known inhibitor of the validated T. brucei drug target RNA editing ligase 1, in order to improve its predicted binding affinity.
Scanning electron microscope analog of scatterometry

Optical scatterometry has attracted a great deal of interest for linewidth measurement due to its high repeatability and capability of measuring sidewall shape. We have developed an analogous and complementary technique for the scanning electron microscope. The new method, like scatterometry, measures shape parameters (e.g., wall angles) as well as feature widths. Also like scatterometry, it operates by finding a match between the measured signal from an unknown sample and a library of signals calculated for known samples. A physics-based model of the measurement is employed for the calculation of libraries. The method differs from scatterometry in that the signal is an image rather than a scattering pattern, and the probe particles are electrons rather than photons. Because the electron-sample interaction is more highly localized, isolated structures or individual structures within an array can be measured. Results of this technique were compared to an SEM cross section for an isolated polycrystalline silicon line. The agreement was better than 2 nm for the width and 0.2{degrees} for wall angles, differences that can be accounted for by measurement errors arising from line edge roughness.
Aluminium Disoaps as Drag Reducing Agents

Recent articles1–3 dealing with the drag reduction of aluminium disoaps in non-aqueous solvents suggest that some disoaps may be more effective than others in reducing turbulent friction in pipe flows or the like and further that critical concentrations of some disoaps must be exceeded before drag reduction is actually observed. According to the available literature data4 aluminium disoaps may be prepared in a variety of molecular weights, the ultimate molecular weight depending upon the extent of polar impurities, the conditions of preparation for both soap and soap dispersions and ageing effects. So subtle is the influence of soap preparation on the final product, however, that soap batches prepared in nominally the same fashion yielding the same elemental analyses result in colloids of quite different maximum molecular weights4. None the less, when plots of intrinsic viscosity against number-average molecular weight were made, most of the disoap data seem to lie on a common curve irrespective of fatty acid residue4. The available data suggest, for example, that it would be difficult to say that aluminium dilaurate always forms higher molecular weight colloids (or “polymers” of greater length) than does aluminium distearate, or the converse. In order to test for the presence of soap critical drag reducing concentrations and to determine whether or not drag reduction effects increased as disoap monomer weight decreased, I decided to prepare carefully two aluminium disoaps.
Influence of fluoride co-cystallized with sugar on caries development in desalivated rats

Previous studies have shown that fluoride (F) administered concomitantly with sucrose in drinking water, in the diet, or alone is an effective cariostatic agent. The purpose of the present study was to determine the minimum concentration of F co-crystallized with sugar that may be used to prevent dental caries in rats subjected to a severe cariogenic challenge. Desalivated Sprague-Dawley rats, infected with Streptococcus sobrinus, were placed in a Konig-Hofer programmed feeder. The rats received 17 meals daily for 21 days as follows: group (1) sucrose and sterile distilled water (s.d.w.); (2) sucrose and 1 part/10(6) F-water; (3) 1 part/10(6) F-sucrose and s.d.w.; (4) 4 parts/10(6) F-sucrose and s.d.w.; (5) 8 parts/10(6) F-sucrose and s.d.w.; (6) sucrose and 10 parts/10(6) F-water. Essential nutrition was administered by gavage. At death, blood was collected from each animal and one-half of the lower jaw was sonicated in 0.9% saline solution for microbial assessment and F analysis. Keyes smooth-surface and sulcal caries scores were significantly lower in the groups that received 10 parts/10(6) F-water and 8 parts/10(6) F-sucrose than in all other groups. The F concentration in the jaw suspension and plasma were significantly higher in the 10 parts/10(6) F-water and the 8 parts/10(6) F-sucrose groups than in all other groups. The total cultivable flora and Strep. sobrinus populations were lowest in F groups but this did not reach statistical significance. It is concluded that 8 parts/10(6) F co-crystallized with sucrose reduces the cariogenic potential of sugar as effectively as 10 parts/10(6) F in water, that is as little as 1 part/10(6) in sucrose has a significant effect, and that this cariostatic action is related to the amount of F in the oral environment.
Oscillations and instability of a shallow-arch under two-frequency excitation

A shallow, sinusoidal, elastic arch with pinned ends is considered. It is subjected to a distributed load with sinusoidal spatial distribution and an amplitude comprised of two harmonic components. The equation for the response amplitude contains quadratic and cubic non-linearities, as well as damping, and it is solved by numerical integration. The effects of the arch rise and the excitation frequencies on the critical load are investigated, including the influence of primary, subharmonic, superharmonic, and combination resonances. To study the response of the arch, time histories, phase plane portraits, and power spectra are plotted for a number of loading conditions. Various types of limit cycles occur, and in some cases the motion is chaotic.
Effects of bias-sputtering on magnetron-sputtered magneto-optical recording media

Effects of substrate bias on the magnetic properties and microstructure of both RF-magnetron- and DC-magnetron-sputtered magnetooptical recording thin films of TbCo are investigated. It is shown that as an applied RF substrate bias voltage (V/sub b/) becomes more negative, argon entrapment in the TbCo films increases precipitously and the deposition rate decreases. Applying V/sub b/ more negative than -30 V (at a cathode voltage of -0.5 kV) results in the formation of voids and a columnar microstructure in magnetron-sputtered films. The diffraction patterns of these amorphous films reveal traces of microcrystallites a few nanometers in size. In addition to the dominant perpendicular anisotropy, evidence of in-plane magnetization is detected. In contrast to what has been found for RF diode sputtering, substrate bias thus adversely affects the properties of magnetron-sputtered films. >