cssi/SciSciGPT-SciSciNet huggingface dataset:
Extraction, Isolation and Identification of a Luteolytic Substance from Bovine Endometrium

A seriesofexperimentswas conductedleadingtotheisolation and identification ofarachidonic acid as a luteolytic agent in extracts of bovine endometrial tissue. Luteolytic activity was followed duringfractionation of endometrialtissueby measuringcorpusluteum weightsand progesterone contents in the ovariesof pseudopregnant hysterectomized hamsters injected with each fraction. The luteolytic activitywas removed from an active protein fraction and identified as a fatty acid. Fatty acids from the microsomal fraction of the endometrium were found to be particularly active. The luteolysin was identified as arachidonic acid by the following criteria: 1) identical Rf’s for the active material and arachidonic acid in several thin layer chromatography systems, 2) identical retentiontimesformethylatedarachidonicacidand one component of the activesubstanceon gas liquidchromatography (GLC), usingthreeseparatecolumns and 3) identical mass spectrafor arachidonicacid and one component of the activematerialobtainedby GLC. Sufficient arachidonicacidwas presentintheactivefractions toproducetheluteolytic effects observed. The effectof arachidonicacid is specific;no other similarfattyacids tested were luteolytic. Unsaturation seems essential for luteolytic activity, since hydrogenation of both arachidonic and thepurifiedactiveendometrialfractiondestroyedthe activity. The role of arachidonic acid of uterineorigininluteolysis in thecow remainstobe determined.
Gain‐area product limitation of circular aperture

Circular apertures are synthesized for maximization of the minimum gain over the coverage area. This study develops the gain-coverage area product limitation for circular apertures. Two conclusions are: (i) The gain-coverage area product is not directly proportional to the aperture diameter, (ii) The in-phase field is the proper field to use in small aperture.
A latent trait approach to the development of persistent stuttering.

The premise that stuttering disorders develop according to the orthogentic principle, preceding in a continuous, unilinear fashion from a state of relative lack of differentiation to a state of increasing differentiation and hierarchic integration, was examined. Responses to Woolf's Perceptions of Stuttering Inventory of 87 individuals who stutter were analyzed using a Rasch 1980 latent trait model for dichotomously scored data. Analyses of responses indicated struggle, avoidance, and expectation through the development of stuttering that became increasingly articulated, integrated, stable, and yet responsive to environmental changes. Four stages of development were noted: Stage I was characterized by the expectation of interruptions in the flow of speech, the addition of unnecessary sounds, and general body tension. Stage II was typified by distinctions between troublesome and not so troublesome words and sounds and between the speaker and various audiences and contexts for speaking. In Stage III, speech...
The Keeping Quality of Samples of Commercially Dried Milk Packed in Air and in Inert Gas

The primary cause for the spoilage of dried milk is the autoxidation of the fat. The rate of autoxidation varies with the quality of the milk; the moisture, copper, and iron content; the method of processing; the temperature of storage; and the oxygen content of the atmosphere of the container. With the advent of the war a special need arose for dried milk that would remain in good condition for at least six months to one year under severe conditions of handling and storage. At that time some of the dried milks were packaged in air and some in inert gas or gases. Among the questions which confronted the potential users of large quantities of the product as well as manufacturers, were (a) what is the general keeping quality of commercial dried milk at different temperatures of storage; (b) how can the keeping quality of dried milks be predicted; and (c) to what extent can the keeping quality be augmented by packing the product in an inert gas ? The work described herein was designed to answer these questions. EXPERIMENTAL
New classical versus neoclassical frameworks: a review of Yang

Abstract Yang (2001) summarizes new classical economics, pioneered by Yang (1988). Individuals are consumer-producers; consumption is linked to the level of productive specialization. The key parameter is an “iceberg” transaction cost (i.e., one dollar spent means less than one dollar received). Autarky (specialization) occurs when transactions costs are above (below) a certain threshold. Firms are collections of consumer-producers tied together by contracts. Trade occurs even if individuals have identical preferences and productive capabilities because there are increasing returns to specialization. The division of labor, the extent of the market and economic organization are characterized by aggregating.
A naturally derived dextran–peptide vector for microRNA antagomir delivery

Single stranded microRNAs and their antagomirs are unstable and polyanionic, which impedes efficient cellular uptake and reduces half-life. Therefore, effective delivery systems with low toxicity for microRNAs are urgently needed for the success of microRNA-based therapy. Here, a dextran–peptide hybrid, Dex10-R5H5(40%), was developed as a carrier to deliver microRNAs. Dex10-R5H5(40%) loaded with antagomir-149 could reduce the level of endogenous microRNA-149 by 76% and it is more effective than the commercially available transfection reagent, RNAiMAX, which leads to 67% reduction. Additionally, Dex10-R5H5(40%) exhibited no cytotoxicity to HepG2 cells. These results indicate that the dextran–peptide hybrid may be a promising delivery system for the safe and efficient microRNA-based therapy.
Race and sex differences in cardiovascular recovery from acute stress.

Abstract To evaluate the effects of race and gender on recovery, i.e. the relative return to baseline after a stress challenge, cardiovascular and catecholamine measures were examined before, during, and after two standardized laboratory Stressors (a speaking and a mirror tracing task) in a group of 85 Black and White men and women (mean age 35.6 years, range 20 to 52). For the speech task, White men showed the least systolic ( p p p p
Chlamydia pneumoniae and atherosclerosis: Links to the disease process

Chlamydia pneumoniae is an obligate intracellular prokaryotic human pathogen responsible for a significant portion of atypical pneumonia and associated with a variety of chronic sequelae, the most significant of which is atherosclerosis. The organism is endowed with several attributes that may contribute to the development of atherosclerotic lesions or promote tissue damage at the site of an existing lesion. Two key events that are directly involved in the atherogenic process include the development of foam cells from macrophages and the oxidation of lipoproteins at the site of lesion development. The former process allows for deposition of cholesterol-containing low-density lipoprotein (LDL) and the latter can contribute directly to tissue damage locally. We have hypothesized that C pneumoniae may interact with mononuclear phagocytes in ways that are consistent with the view that this organism contributes to atherosclerotic lesion development. We have demonstrated that the presence of C pneumoniae causes macrophage foam cell formation and lipid oxidation with murine and human cells cocultured in the presence of LDL. In addition, we have provided evidence that implicates 2 putative chlamydial virulence factors in the development of these pathologic processes. Chlamydial lipopolysaccharide has been shown to cause macrophages to develop into foam cells in the presence of LDL, and the 60-kDa chlamydial heat shock protein (cHsp60), a known pathogenesis-inducing protein, has been found to contribute to oxidation of LDL in the presence of macrophages. Work is currently underway to define mechanisms involved in these processes and to further refine the putative role of C pneumoniae in atherogenesis and atherosclerotic lesion development.
Fault Adaptive Formation Control of Mobile Robots

A supervisory control framework for a team of mobile robots to accomplish a given task in the presence of system faults is presented in this paper. The supervisor, which contains the upper-level switching logic, coordinates a set of lower-level controllers to accomplish a task. The stability analysis of both the lower-level controllers and the internal dynamics associated with them are presented. A switching scheme that satisfies the input constraints and guarantees the stability of the overall system is developed. Results from a leader-follower task with a two-robot team are presented. In this task, the follower becomes the leader when the leader develops a fault by using three lower-level controllers and a switching logic that guarantees stability of the entire operation.Copyright © 2004 by ASME
Characteristics of the swallowing reflex induced by peripheral nerve and brain stem stimulation

Abstract Electrical stimulation of the brain stem through a multiple electrode array indicates that discrete sites evoke the buccopharyngeal component of the swallow. Variation of pulse patterns indicate that the frequency specificity of internal laryngeal nerve stimulation is maintained within the brain stem pathways evoking the swallowing. This frequency specificity suggests that the optimum frequencies of electrical stimulation simulate the integrative input of fibers of the nerve and determine the motor response and synergy of active muscles (i.e., glottic closure, vomiting). Histological verification of the electrode positions in the brain stem indicates that positive points are heavily clustered ventral to the solitarius complex in the dorsal reticular formation. This region receives divergent sensory inflow, particularly from the solitarius complex, and has extensive connections with many of the cranial motor nuclei and the brain stem reticular formation. The most rostral positive points are located in the medial reticular formation at the rostral pole of the inferior olive, a region which previous studies indicated must remain intact for the sequential muscular activity of the buccopharyngeal phase of the swallowing reflex. Evidence suggests a diversified pathway for the control of the swallow originating with the primary afferent fibers in the tractus solitarius. It suggests a sensory-integrative segment located in the dorsal reticular formation ventral to the solitarius complex and a more rostral extension to a discrete magnocellular region of the reticular formation which serves as the final penultimate pathway for motor nuclei control.
Initiation and Repair of Intentional Communication Acts by Adults with Severe to Profound Cognitive Disabilities.

This study assessed the communication initiation and repair behaviors of 28 individuals with severe to profound mental retardation in a variety of experimental conditions. All of these individuals ...
Residues in established alfalfa treated with granulated phorate (Thimet) and their effect on cattle fed the hay.

Granulated phorate (formerly designated as Thimet) at 1 and 4 pounds actual per acre was applied to each of two plots of established alfalfa immediately following cutting and prior to an irrigation. Hay from these two plots harvested 27 days after treatment, was fed to two groups of five steers each for a 1-month period, while a similar group was fed hay from an untreated plot. All groups received untreated hay for a second month. Cattle fed hay from the 4-pound treatment gained weight at a lesser rate than cattle fed hay from the 1-pound treatment, and these in turn gained at a lesser rate than cattle fed untreated hay. The differences, however, were not significant. These differences were smaller during the second month when only untreated hay was fed to the three groups; however, the reduced number of individuals does not allow a valid comparison for this period. Residue determinations using an electrometric technique involving inhibition of blood plasma cholines terase were made on alfalfa samples taken during the growth period following treatment. Maximum residue concentrations, 390 ± 236 and 520±225 parts per million for the lower and higher treatment rates, respectively, were found on the third day after treatment. Samples from the 1-pound plot showed no residues on the 14th day, while those from the 4-pound rate continued to show residues through the 21st and perhaps through the 25th day. No residues were found in air air-dried hay from the 4-pound plot harvested on the 27th day. Cholinesterase activity of blood samples taken periodically from the steers during the feeding period was determined by a spectrophotometric method. Considerable variation in this activity was found between animals within groups and furthermore between sampling dates on individual animals. No evidence was found to indicate that blood cholinesterase activity was appreciably affected by the ingestion of hay from either of the two treatments.
Predicting dishonest actions using the theory of planned behavior

Abstract The prediction of dishonest actions was studied in the context of the theory of planned behavior. College students completed a questionnaire that assessed attitudes, subjective norms, perceptions of behavioral control, intentions, and perceptions of moral obligations, as well as self-reports of behavior with respect to cheating on a test, shoplifting, and lying to get out of assignments. A subsample of respondents returned several months later for a second administration of the questionnaire. Multiple regression analyses showed that the theory of planned behavior predicted intentions with a high degree of accuracy, and that it was moderately successful in the prediction of actual behavior. Addition of perceived moral obligations to the prediction equation improved prediction of reported lying behavior, but did not help to account for much variance in cheating and shoplifting. Self-reports of past dishonesty were used to evaluate the sufficiency of the theory of planned behavior.
Blunt trauma to the carotid arteries

Abstract Blunt carotid artery trauma is an uncommon but potentially dangerous clinical entity. We report eight patients from a 10-year interval who sustained blunt injuries to the carotid arteries. Six of eight patients suffered a hyperextension injury or had a cervical spine fracture or both. Arteriography revealed four arterial dissections and four thrombotic occlusions. Two asymptomatic common carotid artery occlusions and one dissection with transient ischemic attacks had successful arterial reconstructions. Five patients were treated nonoperatively: three internal carotid artery dissections with minor or no neurologic deficit; one asymptomatic thrombosis; and one internal carotid artery thrombosis with a major fixed neurologic deficit that did not improve. No patient died, and seven of eight made a complete neurologic recovery or remained asymptomatic. The diagnosis of blunt carotid artery injuries should be suspected in patients with neck hyperextension injuries or with cervical spine fractures as well as in patients with neurologic deficits not explained by intracranial trauma. Duplex scanning may be a useful noninvasive study. Surgery is indicated for selected patients with accessible lesions who have minor or no neurologic deficits. Asymptomatic patients with small intimal flaps or dissections may be successfully treated nonoperatively. (J VASC SURG 1991;14:789-95.)
The Role of Boundary Conditions on the Thermal Stability of a Landau Slab

Abstract Landau's analysis for the thermal stability of an infinite plane slab is re-solved with four commonly encountered boundary conditions other than a constant temperature on the slab surfaces. Consistent with Landau's findings, critical parameters are identified for the slab with each of the chosen modes of peripheral heat transfer. These critical constants for thermal stability of the slab may be significant to the service-worthiness of industrial products, to the life span of structures, as well as to public safety.
Hormonal changes with cholesterol reduction: a double-blind pilot study.

Summary Background: The lowering of high serum cholesterol levels may be associated with increased non-cardiac mortality due to behavioral changes, although such endpoints are likely rare. Objective: This current study sought to determine if hormonal changes accompany pharmacologically induced decreases in serum cholesterol levels. Method: Cholesterol, dopamine, homovanillic acid (HVA), serotonin, 5-HIAA, testosterone, cortisol and pregnenolone were measured at baseline and after 4 weeks of treatment. Results: Subjects’ cholesterol levels significantly declined within 4 weeks. Concomitant significant increase in dopamine and HVA were noted. Conclusion: Although this study is limited in size, it raises the possibility that cholesterol-lowering drug treatment is associated with hormonal perturbations.
Analysis of directional dependence using asymmetric copula-based regression models

The directional dependence between variables using asymmetric copula regression has drawn much attention in recent years. There are, however, some critical issues which have not been properly addressed in regards to the statistical inference of the directional dependence. For example, the previous use of asymmetric copulas failed to fully capture the dependence patterns between variables, and the method used for the parameter estimation was not optimal. In addition, no method was considered for selecting a suitable asymmetric copula or for computing the general measurements of the directional dependence when there are no closed-form expressions. In this paper, we propose a generalized multiple-step procedure for the full inference of the directional dependence in joint behaviour based on the asymmetric copula regression. The proposed procedure utilizes several novel methodologies that have not been considered in the literature of the analysis of directional dependence. The performance and advantages of th...
Ablation of ventricular arrhythmia in patients with heart failure

Ventricular arrhythmias (VAs) in patients with cardiomyopathy and advanced-symptom class heart failure (HF) are associated with significant morbidity and mortality. VAs are typically managed with antiarrhythmic drug therapy and implantable cardiac defibrillators (ICD). Although ICDs are highly effective in reducing sudden cardiac death by termination of VA, they do not prevent arrhythmia recurrences. Recurrent shocks are not only associated with poor quality of life but also progressive HF and increased mortality and morbidity. Radiofrequency catheter ablation has emerged as an important therapeutic option for patients with drug-refractory ventricular tachycardia to reduce or prevent ICD shocks.
Nickel(II) sorption on hydrous silica: A kinetic and thermodynamic study

Sorption of nickel, Ni2+, on SiO2 . xH2O (silica gel) has been studied as a function of time conditions: amount of silica gel: 0.10-1.00 g, nickel concentration: 5.00 . 10-5-1.20 . 10-3M, ionic strength: 0.20-1.40M NaClO4, pH 6.50 to 8.50, and temperature 273-318 K. From the kinetic data, the diffusion coefficient of Ni2+ ion was calculated to be 1.28(±0.07) . 10-11 m2 . s-1 under particle diffusion-controlled conditions. The sorption rate was determined as 3.79(±0.35) . 10-3 s-1 at 298 K, pH 8.40 in 0.20M (NaClO4). The sorption data were fitted to Freundlich, Langmuir and Dubinin-Radushkevich (D-R) isotherms. Nickel sorption on 0.20 g silica gel decreased with ionic strength from 77.70±0.70% (0.20M NaClO4) to 16.12±0.37% (1.40M NaClO4) at intial pH of 8.50±0.05. A gradual decrease in pH with increasing ionic strength suggests an ion exchange mechanism and the sorption of Ni2+ on silica gel increasing with temperature indicates an endothermic enthalpy. The effect of different ligands such as fluoride, carbonate, phosphate and oxalate on Ni2+ sorption on silica gel was studied.
Vapor Phase Conversion of α-Alumina + Zirconia Composites into Sodium Ion Conducting Na-β″-Alumina + Zirconia Solid Electrolytes

Two phase composites of α-alumina + 3 mol.% Y2O3-stabilized zirconia (YSZ) with both phases being contiguous were fabricated by sintering powder compacts over a temperature range from 1500°C to 1800°C. The sintered samples were embedded in Na-β''-alumina powder and thermally treated over a temperature range from 1250°C to 1450°C for up to 32 hours. This thermal treatment led to the conversion of α-alumina + YSZ composites into Na-β''-alumina + YSZ composites. The mechanism of conversion involves a coupled transport of Na+ through the Na-β''-alumina and of O2− through the YSZ. The kinetics of conversion was investigated by measuring the conversion thickness as a function of time. A model for the conversion kinetics is developed which involves two interface steps (at the gas/solid interface and at the α-alumina + YSZ/Na-β''-alumina + YSZ reaction front) and a coupled transport of Na+ through Na-β''-alumina and of O2− through YSZ. The data are analyzed using the model developed. At small thicknesses, the kinetics tends to be interface-controlled. At large thicknesses, the kinetics approaches diffusion control.
Fiber-optic probes for cyanide using metalloporphyrins and a corrin

Fiber-optic probes for cyanide detection were constructed using metalloporphyrins and a corrin. The probes are based on a change in absorbance that occurs when cyanide coordinates with the reagent used. Response times are as fast as 2 min for cyanide concentrations above 1 × 10−5 M. The reproducibility at a given cyanide concentration level varies for the different reagents, but is most often below 5% (r.s.d.) for the useful portion of the calibration graph. The corrin-based probe is reversible and can be reused. The utility of each reagent is characterized in terms of response time, useful concentration range and reversibility.
Fault tolerant control of an autonomous underwater vehicle under thruster redundancy: simulations and experiments

An approach to the allocation of thruster forces of an autonomous underwater vehicle (AUV) is investigated. Generally, the number of thrusters in an AUV is more than what is minimally required to produce the desired motion. We investigate how to exploit the excess number of thrusters to accommodate thruster faults during operation. First, a redundancy resolution scheme is presented that takes into account the presence of excess number of thrusters along with any thruster faults and determines the reference thruster forces to produce the desired motion. These reference thruster forces are utilized in the thruster controller to generate the required motion. This approach resolves the thruster redundancy in the Cartesian space and allows the AUV to track the task-space trajectories with asymptotic reduction of the task-space errors. Results from both computer simulations and experiments are provided to demonstrate the viability of the proposed scheme. The paper is built upon the preliminary concept proposed earlier by Podder and Sarkar (1999).
Antibodies in Action: Role of Human Opsonins in Killing Salmonella enterica Serovar Typhi

Although vaccines have been available for over a century, a correlate of protection for typhoid fever has yet to be identified. Antibodies are produced in response to typhoid infection and vaccination and are generally used as the gold standard for determining vaccine immunogenicity, even though their role in clearance of Salmonella enterica serovar Typhi infections is poorly defined. Here, we describe the first functional characterization of S. Typhi-specific antibodies following vaccination with a new vaccine, M01ZH09 (Ty2 ΔaroC ΔssaV). We determined that postvaccination sera increased the uptake of wild-type S. Typhi by human macrophages up to 2.3-fold relative to prevaccination (day 0) or placebo samples. These results were recapitulated using immunoglobulins purified from postvaccination serum, demonstrating that antibodies were largely responsible for increases in uptake. Imaging verified that macrophages internalized 2- to 9.5-fold more S. Typhi when the bacteria were opsonized with postvaccination sera than when the bacteria were opsonized with day 0 or placebo sera. Once inside macrophages, the survival of S. Typhi was reduced as much as 50% when opsonized with postvaccination sera relative to day 0 or placebo serum samples. Lastly, bactericidal assays indicated that antibodies generated postvaccination were recognized by complement factors and assisted in killing S. Typhi: mean postvaccination bactericidal antibody titers were higher at all time points than placebo and day 0 titers. These data clearly demonstrate that there are at least two mechanisms by which antibodies facilitate killing of S. Typhi. Future work could lead to improved immunogenicity tests associated with vaccine efficacy and the identification of correlates of protection against typhoid fever.
Heat Transfer Enhancement Using Angled Grooves as Turbulence Promoters

An experimental study is conducted on a simulated internal cooling channel of a turbine airfoil using angled grooves and combination of grooves-ribs to enhance the heat transfer from the wall. The grooves are angled at 45° to the mainstream flow direction and combinations of four different geometries are studied that include: (1) angled grooves with a pitch, p/δ = 10, (2) angled groove with a larger pitch, p/δ = 15, (3) combination of angled groove and 45° angled rib, and (4) combination of angled groove with transverse rib. Transient liquid crystal experiments are conducted for a Reynolds number range of 13,000–55,000, and local and averaged heat transfer coefficient values are presented for all the geometries. Pressure drops are measured between the inlet and the exit of the grooved channel and friction factors are calculated. The combination of the angled groove and 45° angled rib provided the highest performance factor of the four cases considered, and these values were higher or comparable to among the best-performing rib geometries (45-degree broken ribs) commonly used in gas turbine airfoils.Copyright © 2013 by ASME
Nanostructure and molecular mechanics of spider dragline silk protein assemblies.

Spider silk is a self-assembling biopolymer that outperforms most known materials in terms of its mechanical performance, despite its underlying weak chemical bonding based on H-bonds. While experimental studies have shown that the molecular structure of silk proteins has a direct influence on the stiffness, toughness and failure strength of silk, no molecular-level analysis of the nanostructure and associated mechanical properties of silk assemblies have been reported. Here, we report atomic-level structures of MaSp1 and MaSp2 proteins from the Nephila clavipes spider dragline silk sequence, obtained using replica exchange molecular dynamics, and subject these structures to mechanical loading for a detailed nanomechanical analysis. The structural analysis reveals that poly-alanine regions in silk predominantly form distinct and orderly beta-sheet crystal domains, while disorderly regions are formed by glycine-rich repeats that consist of 31-helix type structures and beta-turns. Our structural predictions are validated against experimental data based on dihedral angle pair calculations presented in Ramachandran plots, alpha-carbon atomic distances, as well as secondary structure content. Mechanical shearing simulations on selected structures illustrate that the nanoscale behaviour of silk protein assemblies is controlled by the distinctly different secondary structure content and hydrogen bonding in the crystalline and semi-amorphous regions. Both structural and mechanical characterization results show excellent agreement with available experimental evidence. Our findings set the stage for extensive atomistic investigations of silk, which may contribute towards an improved understanding of the source of the strength and toughness of this biological superfibre.
William Larned, Overseer of the Poor: Power and Precariousness in the Early Republic

Abstract He was a loving father who struggled financially. Yet, he also held immense power over the lives of his fellow townspeople in Providence, Rhode Island. Not rich, not poor, but middling, Wi...
Effect of fish oil and sunflower oil supplementation on milk conjugated linoleic acid content for grazing dairy cows

Abstract The objective of this study was to determine the effect of adding fish oil (FO) and sunflower oil (SFO) to grazing dairy cows’ diets on the temporal changes in milk conjugated linoleic acid (cis-9, trans-11 CLA). Sixteen Holstein cows were divided into two diet regimen groups. One group (CONT) was fed a basal diet (7.6 kg DM basis) plus 400 g animal fat. The other group (FOSFO) were fed a basal diet plus 100 g of FO and 300 g of SFO (FOSFO). The cows were milked twice a day and milk samples were collected every 3-day for a period of 21 days. Both groups grazed together on pasture ad libitum and fed treatment diets after the morning and afternoon milking. Milk production, milk fat percentages, milk fat yield, milk protein percentages, and milk protein yield were not affected (P>0.05) by treatment diets. The concentrations of cis-9 trans-11 CLA and vaccenic acid (VA) in milk fat were higher (P
Multiple description transform codes with an application to packetized speech

The design of multiple description transform codes is presented along with approximate results at high rates. This technique is then applied to packetized speech transmission and performance improvements are obtained in packet loss environments. >
Interaction of angiogenesis inhibitor TNP-470 with basic fibroblast growth factor receptors.

TNP-470 is a synthetic analogue of fumagillin that acts as a potent angiogenesis inhibitor. Recently, our laboratory demonstrated that systemic administration of TNP-470 (5.0 mg/kg) decreased the rate of cutaneous wound healing by greater than 20%. In this study, we tested the hypothesis that TNP-470 interferes with the wound repair-stimulating action of basic fibroblast growth factor (bFGF) by competing with endogenous bFGF for its binding sites on the receptor protein. The influence of TNP-470 was examined in vitro in a ligand competition assay of high- and low-affinity receptor binding to (125)I-bFGF in NIH/3T3 cells. Results demonstrated that recognition of (125)I-bFGF by low-affinity growth factor binding sites was significantly decreased (P < 0.01) in the presence of TNP-470. However, TNP-470 inhibition of radiolabeled bFGF binding to high-affinity sites was not significantly affected (P = 0.07). In view of recent studies demonstrating that the low-affinity receptors of bFGF were heparan sulfate proteoglycans, we suggest that the influence of TNP-470 on diminished wound healing is due to its direct recognition by these molecules.
Environmental Adaptation Contributes to Gene Polymorphism across the Arabidopsis thaliana Genome

The level of within-species polymorphism differs greatly among genes in a genome. Many genomic studies have investigated the relationship between gene polymorphism and factors such as recombination rate or expression pattern. However, the polymorphism of a gene is affected not only by its physical properties or functional constraints but also by natural selection on organisms in their environments. Specifically, if functionally divergent alleles enable adaptation to different environments, locus-specific polymorphism may be maintained by spatially heterogeneous natural selection. To test this hypothesis and estimate the extent to which environmental selection shapes the pattern of genome-wide polymorphism, we define the "environmental relevance" of a gene as the proportion of genetic variation explained by environmental factors, after controlling for population structure. We found substantial effects of environmental relevance on patterns of polymorphism among genes. In addition, the correlation between environmental relevance and gene polymorphism is positive, consistent with the expectation that balancing selection among heterogeneous environments maintains genetic variation at ecologically important genes. Comparison of the gene ontology annotations shows that genes with high environmental relevance are enriched in unknown function categories. These results suggest an important role for environmental factors in shaping genome-wide patterns of polymorphism and indicate another direction of genomic study.
Application of macroscopic balances to the identification of gross measurement errors

A systematic method is presented which is capable of both detecting the presence of grossly biased measurement errors and locating the source of these errors in a bioreactor through statistical hypothesis testing. Equality constraints derived from material and energy balances are employed for the detection of data inconsistencies and for the subsequent identification of the suspect measurements by a process of data analysis and rectification. Maximum likelihood techniques are applied to the estimation of the states and parameters of the bioreactor after the suspect measurements have been eliminated. The level if significance is specified by the experimenter while the measurements are assumed to be randomly, normally distributed with zero mean and known variances. Two different approaches of data analysis, batchwise and sequential, that lead to a consistent set of adjustments on the experimental values, are discussed. Several examples based on the fermentation data taken from literature sources are presented to demonstrate the utility of the proposed method, and one set of data is solved numerically to illustrate the computational aspect of the algorithm
Code-size minimization in multiprocessor real-time systems

Program code size is a critical factor in determining the manufacturing cost of many embedded systems, particularly those aimed at the extremely cost-conscious consumer market. However, the focus of most prior theoretical research on partitioning algorithms for real-time multiprocessor platforms has been on ensuring that the cumulative computing requirements of the tasks assigned to each processor do not exceed the processor's computing capacity. We consider the problem of task partitioning in multiprocessor platforms in order to minimize the total code size, in application systems in which there may be several different implementations of each task available, with each implementation having different code sizes and different computing requirements. We prove that the general problem is intractable, and present polynomial-time algorithms for solving (well-defined) special cases of the general problem.
Histophilus somni host–parasite relationships

Histophilus somni (Haemophilus somnus) is one of the key bacterial pathogens involved in the multifactorial etiology of the Bovine Respiratory Disease Complex. This Gram negative pleomorphic rod also causes bovine septicemia, thrombotic meningencephalitis, myocarditis, arthritis, abortion and infertility, as well as disease in sheep, bison and bighorn sheep. Virulence factors include lipooligosaccharide, immunoglobulin binding proteins (as a surface fibrillar network), a major outer membrane protein (MOMP), other outer membrane proteins (OMPs) and exopolysaccharide. Histamine production, biofilm formation and quorum sensing may also contribute to pathogenesis. Antibodies are very important in protection as shown in passive protection studies. The lack of long-term survival of the organism in macrophages, unlike facultative intracellular bacteria, also suggests that antibodies should be critical in protection. Of the immunoglobulin classes, IgG2 antibodies are most implicated in protection and IgE antibodies in immunopathogenesis. The immunodominant antigen recognized by IgE is the MOMP and by IgG2 is a 40 kDa OMP. Pathogenetic synergy of bovine respiratory syncytial virus (BRSV) and H. somni in calves can be attributed, in part at least, to the higher IgE anti-MOMP antibody responses in dually infected calves. Other antigens are probably involved in stimulating host defense or immunopathology as well.
The McCormack model for gas mixtures: The temperature-jump problem

An analytical version of the discrete-ordinates method (the ADO method) is used to establish a concise and particularly accurate solution to the temperature-jump problem for a binary gas mixture described by the McCormack kinetic model. The solution yields, in addition to the temperature-jump coefficient for the general (specular–diffuse) case of Maxwell boundary conditions for each of the two species, the density and temperature profiles for both types of particles. Numerical results are reported for two binary mixtures (Ne-Ar and He-Xe) with various molar concentrations. The algorithm is considered especially easy to use, and the developed (FORTRAN) code requires typically less than a second on a 2.2 GHz Pentium 4 machine to compute all quantities of interest.
Clinical stability and switch therapy in hospitalised patients with community-acquired pneumonia: are we there yet?

In this issue of the European Respiratory Journal , Engel et al. [1] studied barriers for early switch therapy in hospitalised patients with community-acquired pneumonia (CAP). The authors reference our initial work in the field of switch therapy, published in 1995 in Archives of Internal Medicine [2]. In hospitalised patients with CAP, the standard of practice before 1995 was to use intravenous antibiotics for the full duration of therapy. During our initial study, we obtained consent from patients to see if they were willing to participate in a trial using oral antibiotics once they reached clinical stability. Our Institutional Review Board requested a full evaluation of the initial 10 patients enrolled in the trial to be sure that a switch to oral antibiotics would not be associated with poor clinical outcomes. During the development of the protocol we decided to define clinical stability using two symptoms of CAP (cough and sputum production) and two signs of systemic response (fever and leukocytosis). Patients were defined as …
Extreme Programming Explored

Forward. Preface. Acknowledgments. Introduction. I. PROGRAMMING. 1. How Do You Write a Program? Program Incrementally and Test First. 2. What is Refactoring? "Refactoring: Improving the Design of Existing Code."-Martin Fowler. II. TEAM PRACTICES. 3. What Are XP's Team Practices? "We'll Explore These Practices and Their Alternatives." 4. What is it Like to Program in Pairs? Pair Programming is Exhausting but Productive. 5. Where's the Architecture? Architecture Shows Up in Spikes, the Metaphor, the First Iteration, and Elsewhere. 6. What is the System Metaphor? "The System Metaphor is a Story that Everyone-Customers, Programmers, and Managers-Can Tell About How the System Works,"-Kent Beck. III. PROCESS. 7. How Do You Plan a Release? What are Stories Like? Write, Estimate, and Prioritize Stories. 8. How Do You Plan an Iteration? Iteration Planning Can be Thought of as a Board Game. 9. Customer, Programmer, Manager: What is a Typical Day? Customer: questions, tests, and steering. Programmer: testing, coding, and refactoring. Manager: Project Manager, Tracker, and Coach. 10. Conclusion. Bibliography. Index.
Estrogen Induces Thymic Atrophy by Eliminating Early Thymic Progenitors and Inhibiting Proliferation of β-Selected Thymocytes

Although it has been established that high levels of estrogen can induce thymic involution, the mechanism by which this happens is not known. We have found that daily i.p. injections of the synthetic estrogen 17-beta-estradiol reduce thymus cellularity by 80% over a period of 4-6 days. Although the atrophy is most strikingly observed in the CD4/CD8 double-positive (DP) thymic subset, the loss of thymocytes is not accompanied by a significant increase in thymocyte apoptosis, suggesting that direct killing of cells may not be the dominant means by which estrogens induce thymic atrophy. Instead, we find that estradiol drastically reduces the lineage-negative, Flt3(+)Sca-1(+)c-Kit(+) population in the bone marrow, a population that contains thymic homing progenitors. Within the thymus, we observe that estradiol treatment results in a preferential depletion of early thymic progenitors. In addition, we find that estradiol leads to a significant reduction in the proliferation of thymocytes responding to pre-TCR signals. Reduced proliferation of DN3 and DN4 cell subsets is likely the major contributor to the reduction in DP thymocytes that is observed. The reduction in early thymic progenitors is also likely to contribute to thymic atrophy, as we show that estradiol treatment can reduce the size of Rag1-deficient thymuses, which lack pre-TCR signals and DP thymocytes.
Cell-cycle-dependent protein accumulation by producer and nonproducer murine hybridoma cell lines: A population analysis

Single-cell rates of accumulation of cellular protein have been determined as a function of total protein content using flow cytometry and population balance equations for exponentially growing murine hybridoma cells in the individual G(1), S(1) and G(2) + M cell cycle phases. A novel flow cytometric technique for the identification of hybridoma cells in mitosis was developed and implemented. The data were obtained from a producer cell line which synthesizes and secretes high levels of monoclonal antibodies, and from a nonproducer clone which does not synthesize and secrete substantial amounts of antibody. The results indicate that the kinetics of single-cell protein accumulation in these two cell lines are considerably different. In particular, low protein content G(1) phase producer cells were characterized by a rate of protein accumulation which was approximately five times higher than the mean rate observed for higher protein content producer cells cycle phase. In contrast, the rate of accumulation of protein increased continuously with total protein content for the G(1) phase nonproducer cells. S phase hybridoma cells were characterized by a considerably lower rate of protein accumulation which did not vary much with protein content for either cell line. Finally, G(2) + M phase producer cells demonstrated a negative rate of protein accumulation which indicates that the rates of protein synthesis. It was hypothesized that these differences in total protein accumulation are caused by differences in monoclonal antibody accumulation. The distribution of rates suggests the need for a segregated approach to the modeling of the kinetics of antibody production in hybridomas.
Preconditioned iterative solution of IML/moment method problems

The impedance matrix localization (IML) method replaces the usual method of moments matrix Z by a sparse matrix T. For example, when both Z and T are N*N, T generally has about 50 N nonzero elements. Although this allows each iteration of an iterative method to take only 50 N operations (rather than N/sup 2/), the number of iterations still must be decreased to truly have a fast method. For example, often more than N iterations are necessary for standard methods. Several standard and fast iterative methods are compared. These methods all converge to the exact solution of the matrix equation involving T, and the fast ones do so by using an approximate solution derived from a sparse, approximate factorization of T. The approximate factorization is accurate enough to allow a solution for general problems in five iterations. >
Bottleneck Steiner trees in the plane

A Steiner tree with maximum-weight edge minimized is called a bottleneck Steiner tree (BST). The authors propose a Theta ( mod rho mod log mod rho mod ) time algorithm for constructing a BST on a point set rho , with points labeled as Steiner or demand; a lower bound, in the linear decision tree model, is also established. It is shown that if it is desired to minimize further the number of used Steiner points, then the problem becomes NP-complete. It is shown that when locations of Steiner points are not fixed the problem remains NP-complete; however, if the topology of the final tree is given, then the problem can be solved in Theta ( mod rho mod log mod rho mod ) time. The BST problem can be used, for example, in VLSI layout, communication network design, and (facility) location problems. >
17O NMR spectroscopy: Proton–oxygen coupling in simple alcohols at natural abundance

17O NMR data are reported for 3-pentanol (1), cyclopentanol (2), cyclohexanol (3), and cycloheptanol (4). The 17O NMR signals for 1–4 appeared as doublets, shown to arise from proton–oxygen coupling (1JOH = 76 ± 3 Hz) by proton decoupling experiments. The effect of concentration, temperature, and solvent was examined in detail for 2. Proton—oxygen coupling was observed at low concentrations, decreased at lower temperatures, and was sensitive to solvent.
Sensory Coding in the Grasshopper (Orthoptera: Acrididae) Gustatory System

We reexamine the generally accepted view that gustatory decisions of grasshoppers are based on patterns of input from populations of gustatory receptors. We distinguish the activities of different neurons that respond to stimulation with sucrose and nicotine hydrogen tartrate, compounds that are, respectively, phagostimulatory and deterrent, in Cibolacris parviceps (Walker), Schistocerca americana (Drury), and Syrbula montezuma (Saussure). The responses are qualitatively similar in all 3 species. The neurons responding to sucrose are the same as those responding to sodium chloride and we suggest that the insects are able to distinguish between these compounds by the differential firing rate of 2 neurons, 1 of which has an excitatory input and 1 with an inhibitory input. All the grasshoppers that have been examined electrophysiologically appear to have deterrent-sensitive neurons comparable with those present in some other phytophagous insects. We conclude that the gustatory sensilla of grasshoppers contain neurons that provide qualitatively different information to the central nervous system and in this respect they are comparable with those of other insects. Across-fiber patterning, however, remains an essential feature of a grasshopper's decisions about food quality.
Dissociation of Centrosome Replication Events From Cycles of DNA Synthesis and Mitotic Division in Hydroxyurea-Arrested Chinese Hamster Ovary Cells

Relatively little is known about the mechanisms used by somatic cells to regulate the replication of the centrosome complex. Centrosome doubling was studied in CHO cells by electron microscopy and immunofluorescence microscopy using human autoimmune anticentrosome antiserum, and by Northern blotting using the cDNA encoding portion of the centrosome autoantigen pericentriolar material (PCM)-1. Centrosome doubling could be dissociated from cycles of DNA synthesis and mitotic division by arresting cells at the G1/S boundary of the cell cycle using either hydroxyurea or aphidicolin. Immunofluorescence micros-copy using SPJ human autoimmune anticentrosome antiserum demonstrated that arrested cells were able to undergo numerous rounds of centrosome replication in the absence of cycles of DNA synthesis and mitosis. Northern blot analysis demonstrated that the synthesis and degradation of the mRNA encoding PCM-1 occurred in a cell cycle-dependent fashion in CHO cells with peak levels of PCM-1 mRNA being present in G1 and S phase cells before mRNA amounts dropped to undetectable levels in G2 and M phases. Conversely, cells arrested at the G1/S boundary of the cell cycle maintained PCM-1 mRNA at artificially elevated levels, providing a possible molecular mechanism for explaining the multiple rounds of centrosome replication that occurred in CHO cells during prolonged hydroxyurea-induced arrest. The capacity to replicate centrosomes could be abolished in hydroxyurea-arrested CHO cells by culturing the cells in dialyzed serum. However, the ability to replicate centrosomes and to synthesize PCM-1 mRNA could be re-initiated by adding EGF to the dialyzed serum. This experimental system should be useful for investigating the positive and negative molecular mechanisms used by somatic cells to regulate the replication of centrosomes and for studying and the methods used by somatic cells for coordinating centrosome duplication with other cell cycle progression events.