cssi/SciSciGPT-SciSciNet huggingface dataset:
Combination therapy with 1,3-bis(2-chloroethyl)-1-nitrosourea and low dose rate radiation in the 9L rat brain tumor and spheroid models: implications for brain tumor brachytherapy.

The effects of combination treatment with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and low dose rate radiation were studied in the 9L rat brain tumor in vivo model and the 9L multicellular tumor spheroid model. F-344 rats bearing intracerebral 9L gliosarcomas were implanted with removable /sup 125/I sources. Minimal (peripheral) tumor doses of 6387 rad produced an increased life-span (ILS) of 28% over that of control rats implanted with dummy sources, BCNU alone (13.3 mg/kg) produced in an ILS of 67%, and combination treatment with BCNU and implanted /sup 125/I sources produced an ILS of 167%. As measured by a colony-forming efficiency assay, the greatest cell kill in 9L spheroids occurred when BCNU was administered 24 hours before irradiation from a /sup 137/Cs source at a low dose rate of 5 rad/minute. At a higher dose rate of 210 rad/minute, the time dependence of the effects of combination treatment was identical and therefore independent of dose rate.
Both transmembrane domains of BK β1 subunits are essential to confer the normal phenotype of β1-containing BK channels.

Voltage/Ca2+i-gated, large conductance K+ (BK) channels result from tetrameric association of α (slo1) subunits. In most tissues, BK protein complexes include regulatory β subunits that contain two transmembrane domains (TM1, TM2), an extracellular loop, and two short intracellular termini. Four BK β types have been identified, each presenting a rather selective tissue-specific expression profile. Thus, BK β modifies current phenotype to suit physiology in a tissue-specific manner. The smooth muscle-abundant BK β1 drastically increases the channel's apparent Ca2+i sensitivity. The resulting phenotype is critical for BK channel activity to increase in response to Ca2+ levels reached near the channel during depolarization-induced Ca2+ influx and myocyte contraction. The eventual BK channel activation generates outward K+ currents that drive the membrane potential in the negative direction and eventually counteract depolarization-induced Ca2+ influx. The BK β1 regions responsible for the characteristic phenotype of β1-containing BK channels remain to be identified. We used patch-clamp electrophysiology on channels resulting from the combination of smooth muscle slo1 (cbv1) subunits with smooth muscle-abundant β1, neuron-abundant β4, or chimeras constructed by swapping β1 and β4 regions, and determined the contribution of specific β1 regions to the BK phenotype. At Ca2+ levels found near the channel during myocyte contraction (10 µM), channel complexes that included chimeras having both TMs from β1 and the remaining regions (“background”) from β4 showed a phenotype (Vhalf, τact, τdeact) identical to that of complexes containing wt β1. This phenotype could not be evoked by complexes that included chimeras combining either β1 TM1 or β1 TM2 with a β4 background. Likewise, β “halves” (each including β1 TM1 or β1 TM2) resulting from interrupting the continuity of the EC loop failed to render the normal phenotype, indicating that physical connection between β1 TMs via the EC loop is also necessary for proper channel function.
Studies of a Water Treatment Device That Uses Magnetic Fields

Abstract It is experimentally shown that voltages and currents are produced when conducting solutions are made to flow through a water treatment device that uses magnetic fields. The magnitude of this voltage is found to vary with the solution flow rate in accordance with well-known laws of physics governing the motion of charged particles under the influence of a magnetic field. Current vs flow rate plots and surface pH measurements yield results that are in accord with the presence of enhanced corrosion of the metal housing of the device. It is postulated that the current generated magnetohydrodynamically produces a precipitation initiator that favors the precipitation of scaling salts in the bulk of the solution rather than on the walls of the plumbing.
"Macrophage" nitric oxide synthase is a glucocorticoid-inhibitable primary response gene in 3T3 cells.

Both nitric oxide and prostaglandins are potent paracrine mediators of intercellular communication. An endotoxin-lipopolysaccharide (LPS) inducible form of nitric oxide synthase (mac-NOS) has recently been cloned from murine macrophages. An inducible prostaglandin synthase (TIS1O/PGS-2), cloned from 3T3 cells, is also induced in LPS-activated macrophage. Because of the wide range of ligands that induce primary response genes in 3T3 cells, the ease of studying chimeric promoter constructs in 3T3 cells, and the importance of both nitric oxide and prostaglandins as paracrine mediators, we examined expression of mac-NOS in 3T3 cells. Tetradecanoyl phorbol-13 acetate (TPA), forskolin, platelet-derived growth factor, fibroblast growth factor, and serum all induce mac-NOS expression in Swiss 3T3 cells. Thus the mac-NOS gene can respond to a far wider range of inducers than previously suspected. mac-NOS is a primary response gene; cycloheximide does not block induction. TPA-induced mac-NOS and TIS10/PGS-2 mRNA accumulation patterns are similar. LPS is a potent inducer of mac-NOS in Swiss 3T3 cells but cannot induce TIS10/PGS-2. In contrast, v-src expression induces TIS10/PGS-2 message, but not iNOS message in a BALB/c 3T3 cell line containing a temperature-sensitive v-src gene. Dexamethasone (DEX) prevents induction of TIS10/PGS-2, but not most other primary response genes. DEX also blocks mac-NOS induction in Swiss 3T3 cells. The inducible TIS10/PGS-2 and mac-NOS genes, responsible for the production of two distinct paracrine agents, appear to share many regulatory features in 3T3 cells. © 1993 Wiley-Liss, Inc.
Microwave-assisted cleavage of Weinreb amide for carboxylate protection in the synthesis of a (R)-3-hydroxyalkanoic acid

Abstract A versatile route for the modular synthesis of ( R )-3-hydroxyalkanoic acids, constituents of the naturally biodegradable poly(3-hydroxyalkanoate) polymers, and its application to the synthesis of ( R )-3-hydroxydecanoic acid is described. Key steps include a microwave-assisted catalytic transfer hydrogenation and a facile microwave-assisted hydrolysis of an N -methoxy- N -methyl (Weinreb) amide, which enhances the practicality of this protecting group for carboxylic acids.
Effect of Young's Modulus on the Detachment Force of 7 μm Particles

The detachment force of ground, 7-μm-diameter polyester particles overcoated with clusters of silica having a cluster radius of approximately 100 nm from ceramer substrates with varying Young's mod...
Psychometric correlates of the effects of image-enhancing algorithms on visual performance

Future military imaging devices will have computational capabilities that will allow agile, real-time image enhancement. In preparing for such devices, numerous image enhancement algorithms should be studied. However, these algorithms need evaluating in terms of human visual performance using military-relevant imagery. Evaluating these algorithms through objective performance measures requires extensive time and resources. We investigated several subjective methodologies for down-selecting algorithms to be studied in future research. Degraded imagery was processed using six algorithms and then ranked along with the original non-degraded and degraded imagery through the method of paired comparisons and the method of magnitude estimation, in terms of subjective attitude. These rankings were then compared to objective performance measures: reaction times and errors in finding targets in the processed imagery. In general, we found associations between subjective and objective measures. This leads us to believe that subjective assessment may provide an easy and fast way for down-selecting algorithms but at the same time should not be used in place of objective performance-based measures.
Advances in nuclear medicine instrumentation : considerations in the design and selection of an imaging system

Nuclear medicine remains a vibrant and dynamic medical specialty because it so adeptly marries advances in basic science research, technology, and medical practice in attempting to solve patients’ problems. As a physicist, it is my responsibility to identify or design new instrumentation and techniques, and to implement, validate, and help apply these new approaches in the practice of nuclear medicine. At Johns Hopkins, we are currently in the process of purchasing both a single-photon/coincidence tomographic imaging system and a dedicated positron emission tomography (PET) scanner. Given the exciting advances that have been made, but the conflicting opinions of manufacturers and colleagues alike regarding ”best” choices, it seemed useful to review what is new now, and what is on the horizon, to help identify all of the important considerations in the design and selection of an imaging system. It is important to note that many of the ”advances” described here are in an early stage of development, and may never make it to routine clinical practice. Further, not all of the advances are of equal importance, or have the same degree of general clinical applicability. Please also note that the references contained herein are for illustrative purposes and are not all-inclusive; no implication that those chosen are ”better” than others not mentioned is intended.
Preservice Education: Perspectives about Integrating Caregivers

A disconnect is present between philosophical desire to actively involve caregivers in early intervention (EI) and implementation by EI providers. Preservice education may shape beliefs and build knowledge and skills supporting active participation of caregivers. Two graduate clinicians in speech-language pathology completed a practicum with a two-year-old child, Sam, and his family with half of the sessions including active participation by the caregivers. Analysis of progress notes, individual reflections, and interview transcript yielded clinicians reporting beliefs in collaboration with caregivers and building relationships with caregivers as key to involving caregivers. The clinicians demonstrated knowledge regarding intervention techniques with differences in progress notes based on the presence of the caregiver in sessions. This practicum opportunity promoted development of beliefs, knowledge, and skills about actively involving caregivers in early intervention.
Identification of a cellular protein substrate phosphorylated by the avian sarcoma virus-transforming gene product.

Abstract The avian sarcoma virus-transforming gene product (pp60 src ) appears potentially able to mediate cell transformation via phosphorylation since it is tightly associated with a protein kinase activity. We have searched for and have been able to identify a normal cellular protein that appears to be a substrate of pp60 src . The phosphorylation of this protein (34K) is transformation-specific in ASV-transformed cells of both avian and mammalian origin. Moreover, the 34K polypeptide serves as a substrate for the pp60 src phosphotransferase activity in vitro and is phosphorylated at a site identical to the major site of phosphorylation in vivo. These data suggest that upon transformation the 34,000-dalton protein is phosphorylated directly as a result of pp60 src activity.
Phloem loading and plasmodesmata

Phloem loading, the active accumulation of photosynthate in minor veins, is thought to be the motivating force for translocation. Can loading take place along an entirely symplastic route, through the plasmodesmata, from mesophyll to phloem? Transport of small molecules through the plasmodesmata is apparently passive, and the concept of symplastic phloem loading thus appears to violate thermodynamic principles. Nonetheless, evidence for such a pathway in many plants has been accumulating steadily and an answer to the thermodynamic argument has been put forward. The proposed mechanism involves synthesis and trapping of raffinose and stachyose in the phloem.
Calcium content of St. Thomas' II cardioplegic solution damages ischemic immature myocardium

Clinical application of hypothermic pharmacologic cardioplegia in pediatric cardiac surgery is less than satisfactory, despite its well known benefits in adults. Protection of the ischemic immature rabbit heart with hypothermia alone is better than with hypothermic St. Thomas' II cardioplegic solution. Control of cellular calcium is a critical component of cardioplegic protection. We determined whether the existing calcium content of St. Thomas' II solution (1.2 mmol/L) is responsible for suboptimal protection of the ischemic immature rabbit heart. Modified hypothermic St. Thomas' II solutions (calcium content, 0 to 2.4 mmol/L) were compared with hypothermic Krebs bicarbonate buffer in protecting ischemic immature (7- to 10-day-old) hearts. Hearts (n = 6 per group) underwent aerobic "working" perfusion with Krebs buffer, and cardiac function was measured. The hearts were then arrested with a 3-minute infusion of either cold (14 degrees C) Krebs buffer (1.8 mmol calcium/L) as hypothermia alone or cold St. Thomas' II solution before 6 hours of hypothermic (14 degrees C) global ischemia. Hearts were reperfused, and postischemic enzyme leakage and recovery of function were measured. A bell-shaped dose-response profile for calcium was observed for recovery of aortic flow but not for creatine kinase leakage, with improved protection at lower calcium concentrations. Optimal myocardial protection occurred at a calcium content of 0.3 mmol/L, which was better than with hypothermia alone and standard St. Thomas' II solution. We conclude that the existing calcium content of St. Thomas' II solution is responsible, in part, for its damaging effect on the ischemic immature rabbit heart.
Abstract P6-06-34: Comparing recurrence risk scores derived from 4 immunohistochemistry stains (IHC4) versus oncoType DX

Background: Prognostically relevant biomarkers in breast cancers can be assayed using nucleic acid (e.g. OncoType DX) or protein based (e.g. immunohistochemistry (IHC)) detection stratagies. Nucleic acid tests measure many more markers compared to immunohistochemistry, but are weighted heavily for ER, PR, and HER2 in their prognostic scoring algorithms. Recent data suggest that a panel of 4 IHC stains (IHC4) may have equivalent prognostic ability to multigene assays. The aim of this study was to retrospectively compare IHC4 scores to OncoType DX recurrence scores in a large cohort of patients in our statewide health system. Methods: Formalin-fixed paraffin-embedded breast cancer samples previously submitted for OncoType DX testing between 2008 and 2011 were obtained and sections stained for ER, PR, HER2, and Ki67 (the IHC4 staining panel). Stained slides were scanned digitally and scored using customized pathologist assisted image analysis algorithms (Leica Biosystems Aperio, Vista CA). The resulting data were used in the modified “Magee Equation 3” (Klein et al. Mod Pathol. 2013. PMID: 23503643) to calculate an IHC4 recurrence score on a numerically comparable scale to that used in the OncoType score. The IHC4 and Oncotype DX scores were directly compared for concordance and correlation. Results: 280 breast cancer samples comprised the study cohort. The mean (median) IHC4 score was 20.13 (19), range: 11-42. The mean (median) OncoType score was 18.48 (16), range: 0-75. Using cut-offs of 0-17 for low risk, 18-30 for intermediate risk, and >30 for high risk, the concordance data is shown in Table 1. Pearson9s correlation coefficient for the entire set was 0.6669. The overall concordance was 56.1%; one-step discordance 43.6%; and two-step discordance: 0.3%. Eliminating the intermediate scores, the concordance was 98.8%. Conclusions: Reasonable agreement was seen between risk scores derived by IHC4 and OncoType DX. Only one discrepancy among 280 scores would have resulted in a different treatment recommendation (low risk by IHC4 and high risk by OncoType). If the IHC4 score is clearly high or low, one would not expect a dramatically different result from Oncotype DX, and the Oncotype DX test may not be needed. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-06-34.
Optimal atrioventricular (AV) pacing interval during temporary AV sequential pacing after cardiac surgery

Temporary dual chamber atrioventricular (AV) pacing is often used to increase cardiac output (CO) after cardiac surgery. The AV interval was varied to investigate the effect on CO in 13 patients. CO was computed from the Fick principle using mixed venous oxygen saturation (SvO2), arterial oxygen saturation (SaO2), hemoglobin, and oxygen consumption (VO2). AV intervals were varied randomly from 0.025 to 0.300 seconds in 0.025-second increments. The effect on CO from increasing the AV interval was dependent on the control CO. In all patients, as the AV interval was increased from 0.025 to 0.100 seconds, CO progressively increased. In most patients, the highest (optimal) CO occurred with AV pacing and averaged 300 mL/min greater than with atrial (A) pacing alone (P 6.0 L/min), CO peaked and averaged 0.5 L/min more than with A pacing. CO was maximal for each of these patients at a unique AV interval between 0.100 and 0.225 seconds, and at intervals greater than 0.225 seconds CO decreased (P < .01). In patients with intermediate CO (4-6 L/min) at AV intervals greater than 0.100 seconds, a plateau in CO was reached. No consistent pattern was seen in patients with low initial CO (< 4.0 L/min). Maximal CO may be achieved by optimizing the AV interval in patients following cardiac surgery. The optimal AV interval is between 0.100 and 0.225 seconds and is different for each patient. Continuous SvO2 monitoring allows rapid evaluation of CO changes and optimization of the AV pacing interval.
Light availability as a possible regulator of cyanobacteria species composition in a shallow subtropical lake

1. Variations in the relative biovolumes of dominant cyanobacterial taxa were evaluated in the context of environmental conditions using canonical correlation analysis (CCorrA) and Redundancy Analysis (RDA). The objective was to test a conceptual model in which underwater irradiance determines dominance by bloom-forming (high light adapted) or non-blooming (low light adapted) taxa. 2. The data set consisted of 404 contiguous observations, collected over a 3-year period at eight pelagic sites, in shallow Lake Okeechobee, Florida, U.S.A. Data included species biovolumes, total phosphorus (TP), total nitrogen (TN), dissolved oxygen (DO) and chlorophyll a concentrations, as well as two indices: underwater irradiance (Secchi depth) and the ratio of Secchi:total depth. 3. The first environmental canonical variable was strongly correlated with the two light-related indices, and negatively correlated with TP. This reflects the predominant role of resuspended P-rich lake sediments in controlling underwater irradiance in the shallow lake. The first species canonical variable displayed a strong negative correlation with Lyngbya limnetica and L. contorta, and positive correlations with Anabaena circinalis, Aphanizomenon flos aquae and Microcystis spp. The results support the conceptual model; the first pair of canonical variables explained 55% of the variation in the species–environmental data set. RDA results provided further support for the hypothesis that irradiance was the major force controlling community structure. 4. One unexpected result was a positive association between Oscillatoria spp. dominance and indicators of high irradiance. This conflicts with past research indicating that Oscillatoria is a low light adapted taxon, and the finding that it is the most abundant taxon in Lake Okeechobee. This may reflect the fact that the two Lyngbya taxa were more strongly associated with low light conditions than Oscillatoria. CCorrA results indicated that Oscillatoria densities are strongly controlled by water temperature. There is a need for more detailed studies of cyanobacteria ecophysiology in order to explain fully the seasonality of phytoplankton in this and other shallow subtropical lakes.
WHO-defined chronic neutrophilic leukemia: a long-term analysis of 12 cases and a critical review of the literature.

WHO-defined chronic neutrophilic leukemia: a long-term analysis of 12 cases and a critical review of the literature
Molecular Dynamics Study of the Ionic Liquid 1-n-Butyl-3-methylimidazolium Hexafluorophosphate

We report the results of a molecular dynamics study of the ionic liquid 1-n-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6], a widely studied ionic liquid. An all-atom force field is developed using a combination of density functional theory calculations and CHARMM 22 parameter values. Molecular dynamics simulations are carried out in the isothermal−isobaric ensemble at three different temperatures. Quantities computed include infrared frequencies, molar volumes, volume expansivities, isothermal compressibililties, self-diffusivities, cation−anion exchange rates, rotational dynamics, and radial distribution functions. Computed thermodynamic properties are in good agreement with available experimental values.
Activity and distribution of phosphoinositidase C in rat sciatic nerve

The hydrolysis of phosphatidylinositol-4,5-bisphosphate (PIP2) by rat sciatic nerve cytosolic phosphoinositidase C [phosphoinositide-specific phospholipase C (PIC)] was studied at neutral pH and at ionic concentrations that approximate intracellular conditions. The principal water-soluble product formed was shown to be inositol trisphosphate by anion exchange chromatography. The maximum hydrolysis rate (2.5 nmol/min/mg protein) was achieved at < 100 nM Ca2+. Hydrolysis was markedly increased to 15 nmol/min/mg protein by inclusion of K+ in the reaction mixture. In the presence of 200 mM K+, the optimum Ca2+ was increased to approximately 600 nM. Higher Ca2+ concentrations progressively inhibited PIP2 hydrolysis. Mg2+ also inhibited the reaction, but the presence of equimolar amounts of ATP and Mg2+ had no effect. Appreciable degradation of phosphatidylinositol-4-phosphate (PIP) also occurred in the nanomolar Ca2+ range, whereas breakdown of phosphatidylinositol (PI) required millimolar Ca2+. The presence of PIP but not PI inhibited PIP2 hydrolysis. Upon subcellular fractionation of nerve, more than 50% of recovered PIC activity was in the cytosol and about 20% was located in a myelin-enriched fraction. Using PIP2 as substrate, PIC activities in nerves from normal and streptozotocin-induced diabetic animals were not different. However, the myelin-associated enzyme from diabetic animals was more labile to freezing and thawing. © 1992 Wiley-Liss, Inc.
Independent role of blood pressure on cardiovascular risk factors in nondiabetic, obese African-American women with family history of type 2 diabetes: Implications for metabolic syndrome components.

Abstract African-American women (AAW) suffer disproportionately from hypertension and its consequences. We investigated the significance of systolic and diastolic blood pressure (SBP/DBP) as components of metabolic syndrome (MetS) in nondiabetic, overweight/obese AAW. We studied 258 AAW (mean age, 42.4 ± 8.4 years and body mass index (BMI), 33.4 ± 8.0 kg/m 2 ) in a cross-sectional manner. We estimated the prevalence of MetS and its components using Adult Treatment Panel (ATP III) criteria, insulin sensitivity (Si), insulin resistance (HOMA-IR), and cardiovascular disease risk factors according to the tertiles of blood pressure (BP). Mean age and BMI did not differ with increases in BP tertiles. At screening, 35.7% of our subjects were hypertensive. MetS was found in 32.2% of our AAW. Prevalence of MetS increased as the tertiles of BP increased (SBP = first [10.5%], second [15.1%], third [58.1%], and DBP=first [9.3%], second [23.3%], third [54.7%]). We found that the components of Adult Treatment Panel (ATP) did not track with the corresponding BP tertiles. However, the prevalence of individuals meeting ATP III criteria for BP was highest in the third tertile of both SBP and DBP. Consequently, the prevalence of MetS was highest in the third vs. first and second tertiles. Using linear regression analysis, SBP and DBP did not correlate with the conventional cardiovascular risk factors, HOMA-IR, or Si. In overweight/obese AAW, we found the components of MetS do not track with BP. In the absence of elevated BP, the prevalence of MetS appears to be very low in overweight and obese AAW. Conversely, elevated BP or hypertension was associated with remarkably higher rates of MetS in our AAW. Therefore BP criteria constitute an important and independent determinant of ATP III definition of MetS in AAW.
Automating Software Engineering Best Practices Using an Open Source Continuous Integration Framework (Abstract Only)

Ideally, software engineering courses should adequately reflect real-world software development so that students obtain a better understanding and experience with practices and techniques used in industry. Our objective is to improve software engineering courses by incorporating best practices for automated software engineering and facilitating rapid feedback for students using an open source continuous integration framework for evaluating student software development. The open source Jenkins Continuous Integration Server is the core of our framework, which provides a consistent environment for building student projects, executing automated test cases, calculating code coverage, executing static analysis, and generating reports for students. By using continuous integration, a common tool in real-world software development, we can incorporate software engineering best practices, introduce students to continuous integration in practice, and provide formative feedback to students throughout the software development lifecycle. We found that 76% or more of students in each of the classes that deploy our framework reported that using Jenkins increased their productivity, and that 84% or more of students in each of the classes reported that using Jenkins increased their code quality.
The Influence of Presentation Format on the “Bigger is Better” (BIB) Effect:

Summary.—Two experiments tested the “bigger is better” (BIB) effect, whereby bigger objects are perceived more favorably than smaller ones. In Experiment 1, participants directly compared pairs of objects and a strong BIB effect was obtained for both positively and negatively valenced stimuli. In Experiment 2, comparative and absolute evaluations were combined in a single experiment and the BIB effect was mediated for positively and negatively valenced stimuli. Taken in combination, the data support a complex hypothesis that pair-wise presentations induce a comparative process that causes a BIB effect. But when objects are evaluated separately, size and valence interact such that increased size evokes more positive ratings of positive objects and more negative ratings for negative objects.
Heme degradation by reactive oxygen species.

Heme proteins play a major role in various biological functions, such as oxygen sensing, electron transport, signal transduction, and antioxidant defense enzymes. Most of these reactions are carried out by redox reactions of heme iron. As the heme is not recycled, most cells containing heme proteins have the microsomal mixed function oxygenase, heme oxygenase, which enzymatically degrades heme to biliverdin, carbon monoxide, and iron. However, the red cell with the largest pool of heme protein, hemoglobin, contains no heme oxygenase, and enzymatic degradation of the red cell heme occurs only after the senescent red cells are removed by the reticuloendothelial system. Therefore, only nonenzymatic heme degradation initiated when the heme iron undergoes redox reactions in the presence of oxygen-producing reactive oxygen species takes place in the red cell. Unlike enzymatic degradation, which specifically attacks the α-methene bridge, reactive oxygen species randomly attack all the carbon methene bridges of t...
Representation and retention of verbatim information

Two experiments are reported that study subjects' memory for active and passive sentences. A reaction time methodolgy is used to measure subjects' memory for verbatim information about the sentence. It is shown that retention of the verbatim information displays the traditional short-term versus long-term discontinuity. The verbatim information can be interfered with by interpolation of meaningless strings of similar words. This is taken as evidence that the encoding of the verbatim information is similar to the encoding for a meaningless string of words. The various data can be accounted for by the ACT model ( Anderson, Language, Memory, and thought. Hillsdale, N.J.: Lawrence Erlbaum Associates, 1976 ) which represents both kinds of information in a propositional network.
Alternating flow in trachea

Abstract An alternating laminar flow in a straight tube used to simulate the respiratory flow in trachea is studied analytically. Flow characteristics are shown to be all affected by the frequency of oscillation. Some qualitative agreement between the present theory and some published experimental results has been found. It is concluded that the theories developed previously for the bronchial tree without considering the oscillatory fluid motion need to be modified.
Intra- and Inter-seasonal Variation in the Socio-Spatial Behavior of Adult Male Collared Lizards, Crotaphytus collaris (Reptilia, Crotaphytidae)

When individuals maintain strong inter-seasonal philopatry to the same territories, males may be able to re-establish territory occupancy without intense intra-sexual aggression, and instead spend more time courting females early in the reproductive season. Furthermore, when some males have prior experience defending the same territories, it may be necessary for young males to exhibit higher levels of aggression because they are establishing a territory for the first time. We tested these hypotheses by examining within-season (1992 and 1997) temporal variation in the social behavior of adult male collared lizards of known age and prior territorial experience in a population where inter-season philopatry to territories is high. Contrary to expectations, the frequency of aggression exhibited by males with and without prior territorial experience did not differ. The frequency of intra-sexual aggression was higher in 1992 than in 1997, perhaps because male competitors were more abundant in 1992. Although there was an interactive effect of year, male display and patrol were low at the beginning of the reproductive season in Apr. and May, reached peaks during midseason in June, and then decreased as reproduction ended in July. The size of territories showed a similar pattern, with males defending larger areas in June. Our data support the philopatry hypothesis in that the establishment of territories occurred without high levels of aggression early in the season, perhaps because territory boundaries have been well defined by high rates of patrol and advertisement during the middle of the previous season. Inter-sexual interactions were most frequent in June rather than at the beginning of the reproductive season. Adult females are producing their second clutches and yearling females are producing their first clutches in June. The high rate of inter-sexual encounters in June supports the hypothesis that males allocate more time to courtship when females are receptive because there are more reproductively active females at this time. The temporal pattern of activities in adult Crotaphytus collaris appears to function as a compromise between competing intra- and inter-sexual social demands on males, allowing males to maximize mating opportunities as well as maintain future access to productive territories.
Isonicotinamide enhances Sir2 protein-mediated silencing and longevity in yeast by raising intracellular NAD+ concentration.

Sirtuins are an evolutionarily conserved family of NAD+-dependent protein deacetylases that function in the regulation of gene transcription, cellular metabolism, and aging. Their activity requires the maintenance of an adequate intracellular NAD+ concentration through the combined action of NAD+ biosynthesis and salvage pathways. Nicotinamide (NAM) is a key NAD+ precursor that is also a byproduct and feedback inhibitor of the deacetylation reaction. In Saccharomyces cerevisiae, the nicotinamidase Pnc1 converts NAM to nicotinic acid (NA), which is then used as a substrate by the NAD+ salvage pathway enzyme NA phosphoribosyltransferase (Npt1). Isonicotinamide (INAM) is an isostere of NAM that stimulates yeast Sir2 deacetylase activity in vitro by alleviating the NAM inhibition. In this study, we determined that INAM stimulates Sir2 through an additional mechanism in vivo, which involves elevation of the intracellular NAD+ concentration. INAM enhanced normal silencing at the rDNA locus but only partially suppressed the silencing defects of an npt1Δ mutant. Yeast cells grown in media lacking NA had a short replicative life span, which was extended by INAM in a SIR2-dependent manner and correlated with increased NAD+. The INAM-induced increase in NAD+ was strongly dependent on Pnc1 and Npt1, suggesting that INAM increases flux through the NAD+ salvage pathway. Part of this effect was mediated by the NR salvage pathways, which generate NAM as a product and require Pnc1 to produce NAD+. We also provide evidence suggesting that INAM influences the expression of multiple NAD+ biosynthesis and salvage pathways to promote homeostasis during stationary phase.
Electronic structure of ferromagnetic hcp cobalt. III. Magnetic hyperfine field

Using the energy bands and wave functions of ferromagnetic cobalt from a self-consistent hybridized tight-binding---orthogonalized-plane-wave ferromagnetic band calculation, we have obtained the core and the band contributions to the hyperfine field at the cobalt nucleus to be, respectively, -380.1 and -42.7 kOe. The core contribution of -380.1 kOe, in the moment-perturbation (MP) approach, is composed of contributions from $1s$, $2s$, and $3s$ cores, respectively, of -0.07, -272.4, and -107.7 kOe. These values have been transformed to derive the results that would be expected from a unrestricted-Hartree-Fock (UHF) theory, for the core states and give the individual contributions, in order, from $1s$, $2s$, and $3s$ states as -19.0, -528.1, and +154.6 kOe which add up to about the same total core contribution. The most important effect, causing the individual core contributions to differ substantially in the two methods, is shown to result from exclusion-principle-violating (EPV) diagrams. The small difference of the total core contributions from the MP and the UHF approaches arises from EPV diagrams in which the band electrons are involved. The negative band contribution to the hyperfine field is found to arise from the paired $3d$-like and free-like band states, which overwhelm the positive contribution from the unpaired-spin electrons in the majority-spin band. Arguments are proposed to show that the difference between the theoretical value -422.9 kOe for the hyperfine field and the experimental value of -223.0 could arise from the influence of correlation effect on the $3d$-like band electron wave functions, particularly those at the Fermi surface.
Dynamic software updating

Many important applications must run continuously and without interruption, yet must be changed to fix bugs or upgrade functionality. No prior general-purpose methodology for dynamic updating achieves a practical balance between flexibility, robustness, low overhead, and ease of use.We present a new approach for C-like languages that provides type-safe dynamic updating of native code in an extremely flexible manner (code, data, and types may be updated, at programmer-determined times) and permits the use of automated tools to aid the programmer in the updating process. Our system is based on dynamic patches that both contain the updated code and the code needed to transition from the old version to the new. A novel aspect of our patches is that they consist of verifiable native code (e.g. Proof-Carrying Code [17] or Typed Assembly Language [16]), which is native code accompanied by annotations that allow on-line verification of the code's safety. We discuss how patches are generated mostly automatically, how they are applied using dynamic-linking technology, and how code is compiled to make it updateable.To concretely illustrate our system, we have implemented a dynamically-updateable web server, FlashEd. We discuss our experience building and maintaining FlashEd. Performance experiments show that for FlashEd, the overhead due to updating is typically less than 1%.
One‐Month Repeatability of Emotional Responses to Alcohol

Thirty-four subjects in the Colorado Alcohol Research on Twins and Adoptees (CARTA) were brought back between 30 to 60 days after their initial testing to be retested on all the CARTA procedures. As before, subjects were given a dose of ethanol (0.8 g/kg) calculated to bring their blood alcohol concentration (BAC) to near 0.10 g/dl. Additional doses were given at the end of each of the next 2 hr to maintain their BAC near peak for approximately 3 hr. During both testings, subjects' self-reports of their emotional responses and perceived intoxication following alcohol dosing were only minimally correlated with their alcohol metabolism parameters and reported average level of alcohol use. Repeatabilities (test-retest correlations) for subjects' self-reports of positive affect and of intoxication following alcohol dosing were consistently high, in contrast to earlier reports of minimal repeatabilities for alcohol metabolism and responses to alcohol on physiological, motor coordination, reaction time, and perceptual speed measures. Tester ratings of the subjects' levels of intoxication were also moderately stable between the two testings.
The color of country: Black influence and experience in American country music

Various Artists. From Where I Stand: The Black Experience in Country Music. (3 discs) Warner Bros. 9–46428–2. Ray Charles. The Complete Country & Western Recordings. (4 discs) Rhino Records 75328. Charley Pride. The Essential Charley Pride. RCA/BMG 67428. Charley Pride. The Sensational Charley Pride. Koch 7985. Various Artists. Rhythm Country and Blues. MCA MCAD‐10965.
Role of surface antisite defects in the formation of heterojunctions

Abstract Fermi level pinning positions were measured for Si overlayers on cleaved, n-type GaAs and GaP substrates. The observed positions are 0.73 ± 0.1 eV and 0.98 ± 0.1 eV above the top of the substrate valence band. Theoretical calculations of the surface antisite acceptor levels predict the same chemical trend on going from GaAs to GaP. This agreement and other arguments suggest an important role for surface defects in the formation of semiconductor heterojunctions.
The Combinatorial Approach: A Useful Tool for Studying Epitaxial Processes in Doped Magnetic Semiconductors

; We describe the recent discovery of promising new Ge-based magnetic semiconductors and heterostructures using combinatorial molecular-beam epitaxy for the science and applications of spintronics. We discuss key experimental considerations for implementing combinatorial synthesis and characterization, and highlight important findings in epitaxial films of (100) Ge doped by Co and Mn, specifically the ternary epitaxial phase-diagram, and the novel magnetic and electrical-transport phenomena. We illustriite the natural marriage between the controlled synthesis and combinatorial approach, and demonstrate the usefulness of the approach for studying complex epitaxial, processes.
The Positive Effects of Negative Work: Increased Muscle Strength and Decreased Fall Risk in a Frail Elderly Population

Background. The objective of this study was to determine if a chronic eccentric training intervention, i.e., negative work, could limit or even reverse sarcopenia and its related impairments and functional limitations. Is high-force eccentric training tolerable by elderly people and will it result in improved muscle size, strength, balance, and fall risk? Methods. 21 frail elderly subjects (mean age, 80 years) experienced 11 weeks of lower extremity resistance training. The experimental eccentric (ECC) group (n ¼ 11) performed negative work while exercising on a high-force eccentric ergometer. The active ‘‘controls’’ performed traditional (TRAD) (n ¼ 10) lower extremity resistance exercises (weight training). Muscle fiber cross-sectional area and strength, balance, stair descending abilities, and fall risk were assessed prior to and following this intervention. Results. All ECC subjects who started the negative work intervention completed the study and reported the training to be relatively effortless; they experienced minimal and transient muscle soreness. Both groups experienced a significant increase in muscle fiber cross-sectional area (ECC ¼ 60%, TRAD ¼ 41%). Only the ECC group experienced significant improvements in strength (60%), balance (7%), and stair descent (21%) abilities. The timed up and go task improved in both groups, but only the ECC group went from a high to a low fall risk. Conclusions. These data demonstrate that lower extremity resistance exercise can improve muscle structure and function in those with limited exercise tolerance. The greater strength increase following negative work training resulted in improved balance, stair descent, and fall risk only in the ECC group. Because low energy cost is coupled to high force production with eccentric exercise, this intervention may be useful for a number of patients that are otherwise unable to achieve high muscle forces with traditional resistance exercise.
Defending the Hobbesian Right of Self-Defense

A well-known part of Hobbes's political theory is his discussion of the inalienability of the right of self-defense. In this article, I present and defend a reinterpretation of Hobbes's account of self-defense. I begin by showing the weaknesses of the standard interpretation of this account: It rests on an implausible thesis about the evil of death; it renders Hobbes's applications of the right of self-defense inexplicable; and it conflicts with Hobbes's claim that there are cases in which the right of self-defense can be given up. I argue that we should understand Hobbes's claim to be that the right of self-defense is inalienable only in the social contract, and I offer a new interpretation of how his argument on this point might go.
The Effect of Immersion on the Breaking Force and Failure Locus in an Epoxy/Mild Steel System

Abstract This paper presents the effects of immersion on the adhesion behavior in a polyamide-cured epoxy system immersed in sodium chloride electrolyte adjusted to three different pH values. The strength of lap shear joints was measured before and after exposure and after redrying. The failure locus was determined on a macroscopic and microscopic level. It was found that a large adhesion loss occurred upon immersion. Most of that loss was recovered upon redrying. All of the breaking force was recovered when the immersion fluid was distilled water. The locus of failure was primarily through the bulk of the adhesive before immersion. After immersion the failure was interfacial with a thin residue of polymer remaining on the metal surface. These results are discussed with respect to earlier work on the water absorption properties of the system.
Winter wheat and proso millet yield reduction due to sunflower in rotation

Producers wishing to diversify crop production systems from the traditional winter wheat (Triticum aestivum L.)-fallow system of the central Great Plains need information regarding the impact of sunflower (Helianthus annuus L.) on subsequent winter wheat and proso millet (Panicum miliaceum L.) yields. This study was conducted to quantify winter wheat and proso millet yield reductions due to the lower available soil water that exists when sunflower is the prior crop in rotation. Eight crop rotations-including combinations of winter wheat (W), proso millet (M), corn (Zea mays L.) (C), sunflower (Sun), and fallow (F)-were established in 1990 and evaluated for yield, available soil water at planting, and crop water use in 1995, 1996, and 1997. The experiment was conducted at Akron, CO, on a Weld silt loam (fine, smectitic, mesic Aridic Paleustoll). Available soil water at wheat and millet planting was lower where sunflower had been the previous crop than where sunflower was not the previous crop. In dry years, rotations with sunflower as the previous crop had lower wheat and millet water use than other rotations, but averaged over 3 yr, there was no effect of sunflower on wheat or millet water use. Average wheat yield in a W-Sun-F rotation was about 30% lower than wheat yield from W-C-Sun-F, W-M-Sun-F, W-C-F, and W-F. Average millet yield in a M-Sun rotation was 43% lower than millet yield from M-W-C. Wheat yield declined by 178.5 lb/acre (3 bu/acre) for each inch decline in available soil water at planting. Millet yield declined by 295.6 Iblacre for each inch decline in available soil water at planting. In making the decision to include sunflower in crop rotations, producers will have to consider impact on subsequent crop yields, as well as costs of production, market value of crop, impact on pest problems, and total productivity of all crops in the rotation.
Writing as a tool for learning

The faculty at Ward College of Technology CT, USA is expanding emphasis on writing as a method of improving student learning. The approach is three-pronged: first, to expand the writing portion of laboratory reports; second, to include free writing exercises in theory classes; and third, to introduce oral presentations into the laboratory. As a result of these efforts, students are becoming more organized and critical in their thinking and writing, which is reflected in more precise troubleshooting procedures and technical analysis. Grade improvement is noticeable at the middle (B and C) levels. The process writing exercises used are presented, and the suggested methods for the use of oral presentations are described. >
The influence of channel wettability and geometry on water plug formation and drop location in a proton exchange membrane fuel cell flow field

Abstract The critical volume of liquid water required to form a plug in a channel having mixed wettability similar to that found in the flow field of a proton exchange membrane (PEM) fuel cell is computed for a range of gas diffusion layer (GDL) and bipolar plate wettabilities and channel bend dihedral angles. Three gas diffusion layers (GDL) with 80, 110 and 150° contact angles are considered while the bipolar plate wettabilities are varied with static contact angles ranging from 50 to 130°. The critical volume is an intrinsic property of the channel-GDL configuration and has direct implications for the liquid holdup, the water distribution in the flow fields of PEM fuel cells as well as on the pumping parasitic power loss. The plug volume correlations may be used as an optimization tool for water management in channels of mixed wettability. The effect of cross-section geometry on the critical volume is also investigated through a comparison between a square and a trapezoidal channel. Mixed wettability drop simulations reveal that water can be passively removed from the GDL surface to the bipolar plate if the latter has a lower contact angle, potentially avoiding the flooding of the porous electrodes.