cssi/SciSciGPT-SciSciNet huggingface dataset:
Dissociating nicotine and nonnicotine components of cigarette smoking.

Abstract To dissociate the sensorimotor aspects of cigarette smoking from the pharmacologic effects of nicotine, smokers rated the subjective effects of nicotine-containing or denicotinized cigarettes, and intravenous (IV) nicotine or saline infusions. Three groups of participants (n=20 per group) received either: (1) continuous nicotine, (2) pulsed nicotine, or (3) saline. Each group was exposed to an IV condition once while smoking a denicotinized cigarette and once while not smoking, in a 3×2 mixed design. A fourth group (n=20) received saline while smoking their usual brand of cigarette. The dose and rate of nicotine administration were individualized based on previous measures of ad lib smoke intake. Denicotinized cigarette smoke significantly reduced craving and was rated significantly more satisfying and rewarding than the no-smoking conditions. IV nicotine reduced craving for cigarettes, and increased ratings of lightheadedness and dizziness. However, no significant satisfaction or reward was reported after IV nicotine. The combination of IV nicotine and denicotinized cigarette smoke produced effects similar to those of smoking the usual brand of cigarette. The results suggest that sensorimotor factors are critical in mediating the immediate subjective response to smoking, and that the immediate subjective effects of nicotine administered in doses obtained from cigarette smoking are subtle. Thus, addressing smokers' needs for both for the sensorimotor aspects of smoking as well as for the direct CNS effects of nicotine may be critical in enhancing smoking cessation treatment outcome.
School Vending Machine Purchasing Behavior: Results From the 2005 YouthStyles Survey

BACKGROUND: Competitive foods are often available in school vending machines. Providing youth with access to school vending machines, and thus competitive foods, is of concern, considering the continued high prevalence of childhood obesity: competitive foods tend to be energy dense and nutrient poor and can contribute to increased energy intake in children and adolescents. METHODS: To evaluate the relationship between school vending machine purchasing behavior and school vending machine access and individual-level dietary characteristics, we used population-level YouthStyles 2005 survey data to compare nutrition-related policy and behavioral characteristics by the number of weekly vending machine purchases made by public school children and adolescents (N = 86 9 ). Odds ratios (ORs) and corresponding 95 % confidence intervals (Cls) were computed using age- and race/ethnicity-adjusted logistic regression models that were weighted on age and sex of child, annual household income, head of household age, and race/ethnicity of the adult in study. Data were collected in 2005 and analyzed in 200 8. RESULTS: Compared to participants who did not purchase from a vending machine, participants who purchased ≥3 days/week were more likely to (1) have unrestricted access to a school vending machine (OR = 1. 7 1; 95 % CI = 1.1 3 -2. 59 ); ( 2 ) consume regular soda and chocolate candy ≥1 time/day (OR = 3 .21; 95 % CI = 1.8 7 - 5 . 5 1 and OR = 2. 7 1; 95% CI = 1. 34 - 5 . 4 6, respectively); and ( 3 ) purchase pizza or fried foods from a school cafeteria ≥1 day/week (OR = 5 .0 5 ; 95% CI = 3 .10-8.22). CONCLUSIONS: Future studies are needed to establish the contribution that the school-nutrition environment makes on overall youth dietary intake behavior, paying special attention to health disparities between whites and nonwhites.
SIMPLE TEST OF THE EFFECT OF AN ELECTRIC FIELD ON THE 14N-HYPERFINE COUPLING CONSTANT IN NITROXIDE SPIN PROBES

The sensitivity of the 14N-hyperfine splitting of nitroxide spin to the local electric field, Eloc, has often been used to probe the polarity of microenvironments; however, two uncertainties have been faced at once as follows: (i) the value of Eloc in a complex microenvironment and (ii) the effect of Eloc on the hyperfine splitting. In this paper, we study nitroxide free radicals that may be charged (positively or negatively) by varying the pH. The additional charge produces an additional Eloc, whose value we may calculate with confidence, allowing us to focus attention on the effect that Eloc has on the hyperfine splitting. A simple theory is developed that provides a link between the shift in the 14N-hyperfine splitting, ΔAN, and the local electric field, Eloc. To test this approach, we have calculated the ΔAN for several charged nitroxide spin probes and found good agreement (both magnitude and sign) with the measured values using ΔAN = −3.8 × 10-8Eloc (ΔAN in Gauss and Eloc in V/cm), where Eloc is th...
SOUTHERN SECTION INTERDISCIPLINARY BEEF CATTLE SYMPOSIUM: Forage and co-product systems for stockers in the South: Have fundamental shifts in markets changed the optimal system?

Stockering calves in the southern United States has been an economically viable enterprise for decades. Historically, the system that yielded the best opportunity for profitability was to purchase lightweight calves (130 kg to 220 kg) in autumn, add 100 to 200 kg of BW gain, and sell them in the spring. In most years, the value of the BW gain was worth more than the cost of BW gain in this system. With the exponential price increases in feed, fuel, and fertilizer during 2008 and the significant increase in cattle prices, it is prudent to assess the potential for continued profitability in this segment of the beef industry. Evaluation of 37 grazing experiments indicated that the forage systems most likely to result in inexpensive costs of BW gain for stocker calves involve tall fescue with legumes or ryegrass with small grains. Even with increased input prices, these systems still yield economical BW gain for stocker calves. Likewise, many diets can be blended to produce ADG of 1 kg using co-products that are abundant across the South. With many of these co-products, the most important performance factor in determining their value is G:F. In several experiments, DMI has exceeded 3% of BW in stocker calves, and the resulting G:F has been less than desirable. Several experiments have reported G:F of 0.13 to 0.16, resulting in economical BW gain, whereas some experiments have reported G:F as low as 0.09, which could result in BW gain that costs more to produce than it is worth. From 1979, the value of BW gain for stocker calves in Alabama has averaged US$1.05/kg. However, in the last 3 yr, the value of BW gain has risen to $2.32/kg. Fundamental shifts in feed, fuel, and fertilizer prices experienced in the United States between 2005 and 2010 have markedly changed the amount of capital needed to purchase several hundred stocker calves and to provide adequate feedstuffs for BW gain. However, the value of BW gain associated with producing feeder calves from those stockers has experienced a concomitant increase. The optimal system still uses high-quality cool-season forages and supplementation with co-product feeds. With this system, a significant margin of profit still exists for the Southeastern stocker cattle production system.
Fragile site expression in families with von Hippel-Lindau disease

Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder that predisposes to diverse tumors including renal cell carcinoma. Six affected and four unaffected subjects from five families were studied to determine the frequency of fragile site expression. Peripheral lymphocyte cultures from each subject were treated with low folate, 5-fluorodeoxyuridine (FUdR), and FUdR plus caffeine for fragile site induction. A site was considered to be fragile if it was expressed at least two times in half of the affected or unaffected subjects. Of the established sites, four were expressed in the unaffected group (3p14, 6p22, 8q22, and Xp22) and six were expressed in the affected group (3p14, 4q31, 5q31, 7q32, Xp22, and Xq22). Only 3p14 and Xp22 were expressed in both groups. There were four new sites: three (3q26, 6p21, 7p15) in the unaffected group and one (16q24) in the affected group. The 3p14 site was expressed twice as frequently in affected versus unaffected subjects. This finding is of interest because of reports of the involvement of 3p14 in hereditary renal cell carcinoma and in VHL.
Visual recognition memory deficits in methylmercury-exposed Macaca fascicularis infants

Abstract Infant Macaca fascicularis exposed prenatally to maternal subclinical levels of methylmercury (MeHg) and their nonexposed controls were administered a test of visual recognition memory beginning at 210 days postconception (mean postnatal age = 51.88 days,SD = 5.30). The test consisted of a series of problems in which two identical 35 mm slides of a monkey's face were presented for a study period, followed by a test trial in which the previously exposed stimulus was paired with a novel one, and the looking time to each was recorded. The nonexposed group showed differential visual attention to the novel stimuli, indicating visual recognition abilities. The exposed group's visual attention to the novel stimuli was random. These results, in conjunction with earlier findings, suggest that prenatal MeHg exposure is associated with impaired visual recognition memory performance.
Organizational and Institutional Arrangements for E-Government: A Preliminary Report on Contemporary IT Management Approaches in US State Governments

The success of e-government is believed to depend in part on the organizational and institutional arrangements that governments enact for the management of their IT resources. This paper develops the conceptualization of IT management arrangements by considering possible interactions between two dimensions-1) the organization of IT activities and 2) control over decisions about IT activities (also known as governance)-for each of two categories of IT activities-1) IT projects (such as website development) and 2) IT services (such as the operation of networks). In addition, the paper provides preliminary empirical evidence obtained from applying this expanded conceptualization in the context of American state governments. Many states appear to employ centralization of IT activities to offset decentralization of IT control and vice versa. Consequently, neither dimension alone provides a good characterization of governmental IT management arrangements. These findings have the potential to enhance our understanding of the barriers to, and enablers of e-government success.
Factors affecting recruitment age and recruitment probability in the Western Gull Larus occidentalis

We studied recruitment age (i.e. the age that a gull bred for the first time) and the probability that an adult reproduced during its life in three cohorts of Western Gulls Larus occidentalis breeding on southeast Farallon Island. We examined the effects of sex, hatching date, hatching order, brood size and annual variation in food supply during the recruitment period. Modal recruitment ages of males and females were 4 and 5 years, respectively, a difference that was significant. None of the factors examined, including hatching date, hatching order and brood size, had a significant effect on recruitment age. The probability of breeding in males who experienced low food supply in their fourth and fifth years was lower than that of males who experienced favourable food supply in their fourth and fifth years. Recruitment probability (the proportion of the sample group that recruited among those available to recruit during a given year) of 4- and 5-year-old males was lower in the food-poor 1983 El Nino than in years of favourable food supply. The only variable affecting recruitment probability of females was age: recruitment probability was greater among 5-year-olds than 4-year-olds. Recruitment age in males was more sensitive to annual variation in food supply, probably because females have more difficulty recruiting due to an excess of adult females in the population and because of the different roles in reproduction in which males are primarily responsible for provisioning chicks and maintaining the territory.
A proposed theoretical framework for design of decision support systems in computer-integrated manufacturing systems: A cognitive engineering approach

This article attempts to provide a conceptual basis for design of a decision support system (DSS) for the human supervisory controller in computer-integrated manufacturing systems (CIMSs) that acknowledges human cognitive abilities and limitations as well as the unique features of the CIMS environment. Issues related to information overload and to DSS design that are considered relevant to the CIMS environment are first examined. Utilizing a vertical/on-line/horizontal model of information flow within the CIMS, a conceptual basis for DSS design is then provided that considers the demands of the CIMS and the abilities of the human to meet those demands. Examples are provided to illustrate the proposed ideas underlying DSS design.
Influence of Vesicoureteral Reflux and Urinary Tract Infection on Renal Growth in Children with Upper Urinary Tract Duplication

The growth of the renal parenchyma was examined in children with duplicated outflow systems, vesicoureteral reflux (VUR), urinary tract infection (UTI) and no sign of obstruction. Ten patients with reflux occurring only in the caudal system (group A) and 4 patients with reflux both to the caudal and the apical system (group B) were studied shortly after their first UTI (study 1) and then 1.5 to 9 years later (study 2). The frequency of UTI was relatively high during the follow-up period. At urography, renal length and renal area were normal in group A in studies 1 and 2. Parenchymal thickness of the apical pole (APT/L) did not differ from normal values in any of the studies. Parenchymal thickness of the caudal pole (CPT/L) was significantly smaller than normal in both studies. There was also a significant decrease in CPT/L between study 1 and 2. UTI during the first year of life was associated with a greater reduction in CPT/L. The determination of renal length and renal area in children with a duplicated...
A new nonisolated three-port DC-DC converter with high step-up/down ratio

A new nonisolated three-port dc-dc converter integrating PV and battery power is proposed in this paper. The topology includes two coupled inductors and two active-clamp circuits. The coupled inductors are used to achieve high step up/down gain and to reduce the voltage stress on both primary and auxiliary switches. Two sets of active-clamp circuits in the proposed converter are used to recycle the energy stored in the leakage inductors. Therefore, the system efficiency can be improved. Charging/discharging transition of the battery is autonomous while tracking the maximum power of PV source and regulating the output voltage simultaneously. When the charging voltage is too high, the control loop of PV port will be switched from maximum power point tracking (MPPT) to battery voltage regulation. Experimental results of a 200W laboratory prototype are presented to verify the performance of the proposed three-port converter.
Information theory and genetics

A description of the kinds of systems susceptible to information theoretical analysis is given. By means of an example, certain common fallacies in the application of communication theory to biology are illustrated. The entropy-information analogy is discussed. *** DIRECT SUPPORT *** A01E2109 00008
President George W. Bush and his faith-based initiative: creative solution or political minefield?

On 29th January, 2001, President Bush issued an executive order creating a faith-based initiative office. This paper examines the history of the separation of church and state in the United States starting with the Constitution's First Amendment which established the freedom of religion. Pertinent historical facts through the 1990s are presented. The paper then defines President Bush's faith-based initiative and how it will be implemented. There is concern about whether this initiative will violate the Constitutional separation of religion and government. Another concern is how it will affect the religious organisations and the charities it is supposed to be helping. There is also a discussion on whether President Bush's faith-based initiative will have a positive or negative impact on religious organisations as well as keeping then separate from the government. The concern is whether the initiative will benefit and progress society as a whole. Copyright © 2003 Henry Stewart Publications
Exact sampling with coupled Markov chains and applications to statistical mechanics

For many applications it is useful to sample from a finite set of objects in accordance with some particular distribution. One approach is to run an ergodic (i.e., irreducible aperiodic) Markov chain whose stationary distribution is the desired distribution on this set; after the Markov chain has run for M steps, with M sufficiently large, the distribution governing the state of the chain approximates the desired distribution. Unfortunately, it can be difficult to determine how large M needs to be. We describe a simple variant of this method that determines on its own when to stop and that outputs samples in exact accordance with the desired distribution. The method uses couplings which have also played a role in other sampling schemes; however, rather than running the coupled chains from the present into the future, one runs from a distant point in the past up until the present, where the distance into the past that one needs to go is determined during the running of the algorithm itself. If the state space has a partial order that is preserved under the moves of the Markov chain, then the coupling is often particularly efficient. Using our approach, one can sample from the Gibbs distributions associated with various statistical mechanics models (including Ising, random-cluster, ice, and dimer) or choose uniformly at random from the elements of a finite distributive lattice. © 1996 John Wiley & Sons, Inc.
Bilayer pellicle and bilayer-coated prism beamsplitters for the division-of-amplitude photopolarimeter

A procedure is presented for the design of bilayer pellicle and bilayer-coated prism beam splitters that serve as the key optical element of the division-of-amplitude photopolarimeter DOAP. The bilayer con- sists of two transparent thin films of sufficiently different refractive indices whose thicknesses are selected to achieve 50 to 50% split ratio and optimum ellipsometric parameters in reflection and transmission, such that the determinant of the DOAP instrument matrix is maximized at the proper angle of incidence. As a specific example, we present a Ge- coated nitrocellulose NC first-order pellicle beamsplitter for the near IR 2.0 to 2.2 m. Visible designs include a GaP-coated NC fourth-order pellicle and a SiO2-GaP bilayer-coated glass prism at and near the 633-nm wavelength. Operation of these beamsplitters over a range of incidence angles, wavelengths, and in the presence of ±5% film thick- ness errors is also considered. © 2005 Society of Photo-Optical Instrumentation
Chemical and Thermodynamic Characterization of Metal Surfaces for the Adhesive Bonding of Metals

Abstract Several complementary surface analysis techniques were employed to determine the properties of the polished surfaces of titanium-6Al,4V, 2024-T3 aluminum, and interstitial free steel. XPS indicated that the oxides were all approximately 50 A thick and covered with a layer of carbon-containing compounds probably consisting of both hydrocarbons and more highly oxidized carbonaceous materials such as carbonates or bicarbonates. The calculation of wettability envelopes showed all of the surfaces to have similar energetics, possibly because these properties are determined largely by the adsorbed water and hydrocarbons present on all transition metal surfaces. The surface isoelectric points were estimated using indicator dyes and compared to published values. Finally, reflection-absorption infrared spectra were obtained from the aluminum surfaces, allowing the oxide structure to be determined and giving more information about the nature of the overlying carbon-containing compounds.
Liver X receptor α activation with the synthetic ligand T0901317 reduces lung injury and inflammation after hemorrhage and resuscitation via inhibition of the nuclear factor κB pathway

Liver X receptor α (LXRα) is a nuclear transcription factor that regulates lipid metabolism. Recently, it has been shown that activation of LXRα with synthetic ligands has anti-inflammatory effects in atherosclerosis and chemical-induced dermatitis. We investigated the effect of the LXRα agonist, T0901317, on lung inflammation in a rodent model of hemorrhagic shock. Hemorrhagic shock was induced in male rats by withdrawing blood to a goal mean arterial blood pressure of 50 mmHg. Blood pressure was maintained at this level for 3 h, at which point rats were rapidly resuscitated with shed blood. Animals were then treated with T0901317 (50 mg · kg) or vehicle i.p. and sacrificed at 1, 2, and 3 h after resuscitation. Treatment with T0901317 significantly improved the cardiac and stroke volume indices as well as the heart rate of rats during the resuscitation period as compared with vehicle-treated rats. The T0901317-treated animals showed significant improvement in the plasma level of lactate, whereas base deficit and bicarbonate levels both trended toward improvement. The T0901317-treated animals also showed lower levels of plasma cytokines and chemokines monocyte chemoattractant protein 1, macrophage inflammatory protein 1α, TNF-α, KC, and IL-6. Lung injury and neutrophil infiltration were reduced by treatment with T0901317, as evaluated by histology and myeloperoxidase assay. At molecular analysis, treatment with T0901317 increased nuclear LXRα expression and DNA binding while also inhibiting activation of nuclear factor κB, a proinflammatory transcription factor, in the lung. Thus, our data suggest that LXRα is an important modulator of the inflammatory response and lung injury after severe hemorrhagic shock, likely through the inhibition of the nuclear factor κB pathway.
Existence of the dielectric constant in nonpolar fluids

Abstract The dielectric constant ϵ exists (i.e., is well defined) only if the polarization P(r) is locally proportional to the Maxwell electric field E(r), the proportionality constant being independent of position and sample geometry. In this article the existence of ϵ is investigated for a model nonpolar fluid composed of molecules having density-independent harmonic polarizabilities. This investigation requires one to consider the general case in which a sample of arbitrary shape is subjected to a nonuniform external electric field. By expanding P(r) in powers of the molecular polarizability α, it is shown that ϵ is rigorously well defined at least to order α3. (For simplicity the demonstration is given only for molecules of spherical shape, but the generalization to nonspherical molecules is straightforward and the conclusion is unchanged.) An explicit expression for ϵ to this order is automatically obtained; it is identical to a well-known result previously obtained by assuming the existence of ϵ. Terms of higher order than α3 are expected to contribute negligibly to P(r), since the dimensionless parameter corresponding to α is of order 0.1. The dielectric constant is therefore well defined to a high degree of approximation, at both gas and liquid densities, for the molecular model considered.
Coulomb excitation of 67Zn and core-quasiparticle coupling in f52 nuclei

Abstract A qualitative explanation of the low-lying levels of g 9 2 shell nuclei using a recent theoretical improvement upon quasiparticle-phonon coupling theories has motivated the investigation of 67Zn, which belongs in the f 5 2 neutron shell. A Coulomb excitation experiment was performed with 3.2 to 4.86 MeV α-particles. De-excitation γ-rays were observed with a 45 cm3 Ge(Li) detector. In addition to excitation of previously known states at 184.6 keV ( 3 2 − ) and 880.0 keV ( 5 2 − ) , strong excitation of states at 815.2 keV ( 5 2 − , 7 2 − ) and 870.9 keV ( 3 2 − , 5 2 − , 7 2 − ) was observed. The latter state also appears to have been observed in high resolution (d, p) stripping work. Angular distribution data were taken at Eα = 4.0 and 4.86 MeV, and were used to obtain branching ratios, reduced upward transition probabilities, mixing ratios and spin assignments. The B(E2)↑ associated with the 67Zn levels populated in this experiment are (in units of e2 · b2) 184.6 keV (0.0190 ± 0.0014), 393.6 keV (0.00049 ± 0.00003), 815.2 keV (0.029 ± 0.002), 870.9 keV (0.04 ± 0.02), and 888.0 keV (0.0086 ± 0.0006). An extensive diagonalization using three single-quasiparticle states ( f 5 2 , p 3 2 , and P 1 2 ) in 67Zn, each coupled to a core phonon, was carried out and detailed predictions were made for level energies, reduced transition probabilities, magnetic dipole and electric quadrupole moments, relative γ-ray intensities, and mixing ratios. Generally, the predictions are in good agreement with 67Zn experimental data. Data for other f 5 2 shell nuclei lend further qualitative support to a quasiparticle-phonon coupling picture for odd-A nuclei in the f 5 2 shell. It is suggested that an extra 3 2 − low-lying level present in several f 5 2 shell nuclei has characteristics similar to those of the three-quasiparticle “intruder” state described by Kisslinger.
Calculations of V−V Transfer Rates in H2 and Comparison with Experiment†

Recent observations on VV transfer in H2 have shown interesting results. For nonresonant processes, comparison of the experimental rate constants with the results of previous semiclassical calculat...
High rate operation of warm-liquid ionization chambers

Abstract The effect of positive ion buildup at high rates in warm-liquid ionization chambers is considered. Measurements made with TMS indicate that warm liquids can operate at SSC particle fluxes.
Effect of Changes in the Flexible Arm on tRNase Z Processing Kinetics

tRNAs are transcribed as precursors and processed in a series of reactions culminating in aminoacylation and translation. Central to tRNA maturation, the 3′ end trailer can be endonucleolytically removed by tRNase Z. A flexible arm (FA) extruded from the body of tRNase Z consists of a structured ααββ hand that binds the elbow of pre-tRNA. Deleting the FA hand causes an almost 100-fold increase in Km with little change in kcat, establishing its contribution to substrate recognition/binding. Remarkably, a 40-residue Ala scan through the FA hand reveals a conserved leucine at the ascending stalk/hand boundary that causes practically the same increase in Km as the hand deletion, thus nearly eliminating its ability to bind substrate. Km also increases with substitutions in the GP (α4–α5) loop and at other conserved residues in the FA hand predicted to contact substrate based on the co-crystal structure. Substitutions that reduce kcat are clustered in the β10–β11 loop.
Interplanetary Dust and Carbonaceous Meteorites: Constraints on Porosity, Mineralogy and Chemistry of Meteors from Rubble-Pile Planetesimals

This paper discusses measured textures, porosity, chemical compositions and the minerals of interplanetary dust and meteorites from primitive planetesimals and how this information can be used to explain some of the observed physical and chemical properties of meteor phenomena.
Economic analysis of earning a PhD degree after completion of a PharmD degree

Objective. To determine the net present value (NPV) and internal rate of return (IRR) for earning a doctor of philosophy (PhD) degree and pursuing careers commonly associated with that degree after completion of a doctor of pharmacy (PharmD) degree compared to entering pharmacy practice directly upon completion of the PharmD degree.Methods. Income profiles were constructed based on 2008 annual salary data. NPV and IRR were calculated for careers resulting from the PhD degree and compared to those of the practicing community pharmacist. Trends in IRR also were examined across career paths from 1982 to 2008. A priori assumptions were developed and sensitivity analyses were conducted.Results. The NPVs for all careers associated with the PhD degree were negative compared to that of the practicing community pharmacist. IRRs ranged from -1.4% to 1.3% for PhD careers. Longitudinal examination of IRRs indicated a negative trend from 1982 to 2008.Conclusions. Economic financial incentives for PharmD graduates to p...
Smooth muscle stimulating action of venom from the Gila monster, Heloderma suspectum.

Abstract Venom from the Gila monster, Heloderma suspectum Cope, was tested on isolated sections of the guinea pig ileum, rat ascending colon, and rat estronized uterus. A stimulating effect of a delayed nature was found which was neither blocked by atropine nor by the anti-histaminic agent Benadryl. While incubation in a boiling water bath for 20 min destroyed this smooth muscle stimulatory effect, shorter incubation periods did not.
An Investigation of a Model of Academic Motivation for School Counseling.

A theoretical model of academic motivation consisting of (a) academic self-efficacy, (b) purposefulness and intentionality, and (c) support through school counseling for autonomous learning was explored with 346 high school juniors. Regression analysis indicated academic self-efficacy and utilization of school counseling to be significant predictors of academic motivation after controlling for previous school performance. A second regression analysis supported the premise that students who are more optimistic about their future and perceive fewer impediments to future goals will be more likely to use school counseling services. Recommendations for school counseling practice and research are discussed.
A Role for Fas in Negative Selection of Thymocytes In Vivo

To seek information on the role of Fas in negative selection, we examined subsets of thymocytes from normal neonatal mice versus Fas-deficient lpr/lpr mice injected with graded doses of antigen. In normal mice, injection of 1–100 μg of staphylococcal enterotoxin B (SEB) induced clonal elimination of SEB-reactive Vβ8+ cells at the level of the semi-mature population of HSAhi CD4+ 8− cells found in the thymic medulla; deletion of CD4+ 8+ cells was minimal. SEB injection also caused marked elimination of Vβ8+ HSAhi CD4+ 8− thymocytes in lpr/lpr mice. Paradoxically, however, elimination of these cells in lpr/lpr mice was induced by low-to-moderate doses of SEB (≤1 μg) but not by high doses (100 μg). Similar findings applied when T cell receptor transgenic mice were injected with specific peptide. These findings suggest that clonal elimination of semi-mature medullary T cells is Fas independent at low doses of antigen but Fas dependent at high doses. Previous reports documenting that negative selection is not obviously impaired in lpr/lpr mice could thus reflect that the antigens studied were expressed at only a low level.
Assessing the Impact of Massive Out-Migration on Albanian Agriculture

In this paper, we examine the impacts of migration on household-level farm production decisions, including labor allocation, crop diversification, and agricultural and total household incomes, using household survey data from Albania. Results indicate that increased international migration leads to a reduction in household labor allocated to agricultural activities and crop diversity, but has no impact on agricultural income. However, it does lead to higher total incomes. These findings suggest that international migration does not strengthen household agricultural production but instead facilitates the transition away from agriculture. We also consider the effect on agricultural outcomes of the network of adult children who have left home but are still living in Albania. The effect of this local migration on agriculture is the opposite: larger networks lead to higher agricultural incomes and greater agricultural labor per capita.
Polychromatic microdiffraction analysis of defect self-organization in shock deformed single crystals

Abstract A spatially resolved X-ray diffraction method – with a submicron 3D resolution together with SEM and OIM analysis are applied to understand the arrangements of voids, geometrically necessary dislocations and strain gradient distributions in samples of Al (1 2 3) and Cu (0 0 1) single crystals shocked to incipient spallation fracture. We describe how geometrically necessary dislocations and the effective strain gradient alter white beam Laue patterns of the shocked materials. Several distinct structural zones are observed at different depths under the impact surface. The density of geometrically necessary dislocations (GNDs) is extremely high near the impact and back surface of the shock recovered crystals. The spall region is characterized by a large density of mesoscale voids and GNDs. The spall region is separated from the impact and back surfaces by compressed regions with high total dislocation density but lower GNDs density. Self-organization of shear bands is observed in the shock recovered Cu single crystal.
Vitamin-responsive inborn errors of metabolism

Abstract Vitamins are essential precursors of coenzymes. The dietary intake, or exogenous supply that is sufficient to maintain normal metabolic and biochemical equilibrium, defines the requirement of a vitamin for man. Interindividual variation exists in the latter, the large part of which is accomodated by intakes conforming to the recommended dietary allowances (RDA) for individual vitamins. Deficient supply of a vitamin eventually affects all functions dependent on the presence of its coenzyme form; the deficiency state is usually corrected by replacement of the vitamin at the RDA level. Some individuals have a requirement for a particular vitamin that is met only by doses well above the RDA (i.e. at pharmacologic levels of intake). This type of aberration is usually inherited. The mutant gene product impedes some step in the sequence of events that makes the coenzyme form of the vitamin accessible to its apoenzyme(s). A mutation that imposes an exaggerated requirement for a vitamin may alter its transport across membranes, or its conversion into coenzyme (“biosynthetic defect”); alternatively, the mutation may affect an apoenzyme so that the steric relationships between coenzyme and protein are no longer favorable (“binding defect”). In the former, all apoenzymes served by the product of biosynthesis (coenzyme) will be perturbed; in the latter, only the specific apoenzyme is affected. Vitamin responsiveness, either biochemical or clinical indicates that a block in biosynthesis is “leaky”, or that an unfavorable relationship between enzyme and coenzyme can be overcome. It has also been suggested that saturation of a mutant apoenzyme by its coenzyme may cause posttranscriptional induction, by attenuating the rate of enzyme degradation; or the coenzyme may augment an alternate route of metabolism by induction of the enzyme at the first committed step. The mechanisms by which mutations permit vitamin responsiveness among the inborn errors of metabolism, while imposing an inherited aberration in vitamin requirement, are of more than theoretical interest. Individuals, with vitamin-responsive hereditary metabolic disease, in general, have milder variants of the classical (Garrodian) phenotype; moreover, their treatment is relatively simple and the response to it is often dramatic.
Segmenting Images Analytically in Shape Space

This paper presents a novel analytic technique to perform shape-driven segmentation. In our approach, shapes are represented using binary maps, and linear PCA is utilized to provide shape priors for segmentation. Intensity based probability distributions are then employed to convert a given test volume into a binary map representation, and a novel energy functional is proposed whose minimum can be analytically computed to obtain the desired segmentation in the shape space. We compare the proposed method with the log-likelihood based energy to elucidate some key differences. Our algorithm is applied to the segmentation of brain caudate nucleus and hippocampus from MRI data, which is of interest in the study of schizophrenia and Alzheimer's disease. Our validation (we compute the Hausdorff distance and the DICE coefficient between the automatic segmentation and ground-truth) shows that the proposed algorithm is very fast, requires no initialization and outperforms the log-likelihood based energy.
Hydrogen isotopic composition of individual n-alkanes as an intrinsic tracer for bioremediation and source identification of petroleum contamination.

The isotopic signatures of crude oil hydrocarbons are potentially powerful intrinsic tracers to their origins and the processes by which the oils are modified in the environment. Stable carbon isotopic data are of limited use for studying petroleum contaminants because of the relatively small amount of isotopic fractionation that occurs during natural processes. Hydrogen isotopes, in contrast, are commonly fractionated to a much greater extent and as a result display larger variations in δ values. We studied the effect of in vitro aerobic biodegradation on the hydrogen isotopic composition of individual n-alkanes from crude oil. The isotopic analysis was conducted using gas chromatography−thermal conversion−isotope ratio mass spectrometry. In general, biodegradation rates decreased with increasing hydrocarbon chain length, consistent with previous studies. More importantly the n-alkanes that were degraded at the fastest rates (n-C15 to n-C18) also showed the largest overall isotopic fractionation (∼12−25‰...
Developing Progress Monitoring Measures for Secondary Mathematics An Illustration in Algebra

Secondary special educators are in desperate need of progress monitoring measures in mathematics that appropriately reflect their students' instructional content. As educators across the country re...
Doppler measurements of aortic blood flow velocity and acceleration: load-independent indexes of left ventricular performance?

“...a substantial body of evidence has accumulated to indicate that the peak acceleration of blood ejected by the left ventricle into the ascending aorta is probably the most sensitive indicator of ventricular performance. Both peak flow velocity and outflow acceleration can be derived from ultrasonicjlow records without quantitative knowledge of the volume flow rate (stroke volume).” -Robert F. Rushmer, IUD
COMPARISON OF A STOCHASTIC MODEL OF FATIGUE CRACK GROWTH WITH EXPERIMENTS

A stochastic model of fatigue crack growth under constant amplitude loading, derived from a global/local energy balance, is compared with experiment data. Four random variables and a Gaussian white noise random field were assumed to model, respectively the statistical scatter of the crack length versus N curves and their stochastic fluctuations reflecting the effect of stochastic material non-homogeneity within a specimen. The statistical analysis of the so called Virkler and Ghonem-Dore data sets is extensively used to identify the probabilistic characteristics of the random variables and random field and to verify the stochastic model. Based on the importance sampling integration technique the fatigue lifetime probability distributions are effectively calculated. The influence of the particular assumptions accounting for the random material properties is investigated and the quality of the model prediction is verified by comparison with empirical statistical characteristics of the lifetime.
Validation of an Instrument to Measure Community College Student Satisfaction

This article reports the development and validation of a survey instrument to measure community college students'; satisfaction with their educational experiences. The initial survey included 95 questions addressing community college student experiences. Data were collected from 558 community college students during spring of 2001. An exploratory factor analysis was performed to classify the survey items, and the following 11 factors were retained: curriculum and instruction, counseling/advising, facilities, campus climate, orientation, academic development, personal development, availability of classes, financial aid and fees, admissions and course registration, and follow up of academic progress. The final instrument contains 60 questions representing students'; satisfaction with a full range of their community college experiences. Reliability coefficients for the survey ranged from .72 to .92. Limitations and future research directions are also discussed.
Time-dependent approach to scattering in a laser field

We formulate a numerical method for treating the time-dependent scattering of an electron from a potential in the presence of a classical oscillating radiation field. The Schroedinger equation is solved in momentum space, which obviates the need to impose artificial boundaries and facilitates the extraction of the rapidly varying part of the wave function. We present results of a test application to a one-dimensional system with atomic potential ..beta.. exp(-chemically bondxchemically bond/R) exposed to a short pulse.
Training and Mentoring: Family Child Care Providers' Use of Linguistic Inputs in Conversations with Children

Abstract The purpose of this study was to examine the effectiveness of two professional development models in increasing family child care providers’ frequency of linguistic inputs in conversations with young children. The first professional development model consisted of a 10-h in-service training focused on supporting early language development. The second included the same 10-h in-service training program and mentoring. Providers and children at 48 family child care programs participated in this study. The family child care programs were randomly assigned to one of the two professional development models (i.e., training or training with mentoring) or to a control group. Audio recordings of the language environment were collected prior to the in-service training, at the completion of the in-service training, and at the completion of the mentoring. Hierarchical linear modeling was used to examine the average increase in the frequency of providers’ use of linguistic inputs over three observations, conducted before training, immediately at the end of training, and 6 weeks after training. Results indicate that both forms of professional development increased linguistically stimulating inputs as compared to the control group. The professional development model including mentoring support was related to greater increases in providers’ use of informational talk and teaching utterances over in-service training without mentoring.
Simplified electrostatic model for band-gap underestimates in the local-density approximation.

An estimate of the undercounted electrostatic energy terms in local-density-functional total-energy calculations for nonmetallic systems with separated electron-hole pairs is used to derive a simplified correction to density-functional - theory band gaps. The correction is evaluated for Ne, Ar, Kr, LiF, NaCl, CsCl, MgO, CaS, BaS, C, AlP, and Si. The band-gap errors are reduced from 40-50% to 10-15% for most of the systems studied. Conduction-band corrections are shown to be nearly as large as valence-band corrections in free-electron-like semiconductors. 28 references, 1 figure.
Energy Transfer to the Low-Energy Triplet States of 1,3-Dicarbonylazomethine Dyes: The Role of Unique Geometries and Nonadiabatic Behavior

The observed kinetics of energy transfer to PhCO−(CNAr)−CONHPh (1), PhCO−(CNAr)−COPh (2), and PhCONH−(CNAr)−CONHPh (3) (Ar = p-NMe2C6H4) is consistent with formation of two triplet states for each dye: T1 and T2. A Balzani analysis of the data observed for 1 affords triplet energies of 23.4 ± 1.6 and 38.5 ± 1.7 kcal/mol for T1 and T2, respectively, and requires that T1 be formed in reactions having substantial nonadiabatic character. A similar result is found for 2. For 3, T1 and T2 are estimated at 25.0 and 38.5 kcal/mol, respectively, but formation of 3-T1 is found to be largely adiabatic. To rationalize these observations, the dyes have been studied by DFT methods (B3LYP/6-31G*). In the ground state (1-S0) 1 is computed to have a geometry in which the azomethine double bond is coplanar with the anilide fragment but is perpendicular to the carbonyl of the ketone. Similarly, 2-S0 is calculated to have a twisted 1,3-dicarbonyl arrangement. 3-S0, on the other hand, exhibits an intramolecular H-bond betwee...
Clinical Science Review: The Routinization of Intraperitoneal (Intracavitary) Chemotherapy and Immunotherapy

(1986). Clinical Science Review: The Routinization of Intraperitoneal (Intracavitary) Chemotherapy and Immunotherapy. Cancer Investigation: Vol. 4, No. 1, pp. 29-42.
Afferent influences on brain stem auditory nuclei of the chicken: presynaptic action potentials regulate protein synthesis in nucleus magnocellularis neurons

Studies of the avian auditory system indicate that neurons in nucleus magnocellularis (NM) and nucleus laminaris of young animals are dramatically altered by changes in the auditory receptor. We examined the role of presynaptic activity on these transneuronal regulatory events. TTX was used to block action potentials in the auditory nerve. TTX injections into the perilymph reliably blocked all neuronal activity in the cochlear nerve and NM. Far-field recordings of sound- evoked potentials revealed that responses returned within 6–12 hr after a single TTX injection. Changes in protein synthesis by NM neurons were measured by determining the incorporation of 3H-leucine using autoradiography. NM neurons on the side of the brain ipsilateral to the TTX injection were compared to normally active cells on the other side of the same tissue section. Grain counts over individual neurons revealed that a single injection of TTX produced a 40% decrease in grain density in ipsilateral NM neurons within 1.5 hr after the TTX injection. However, by 24 hr after a single TTX injection, grain densities were not different on the 2 sides of the brain. Continuous activity blockade for 6 hr caused the cessation of amino acid incorporation in a portion of NM neurons and a 15–20% decrease in the remaining neurons. These changes in amino acid incorporation are comparable to those following complete removal of the cochlea (Steward and Rubel, 1985). We also examined NM for neuron loss and soma shrinkage after blocking eighth nerve action potentials. TTX injected every 12 hr for 48 hr caused a 20% neuron loss and an 8% shrinkage of the remaining neurons. Similar reductions were found following cochlea removal (Born and Rubel, 1985). It is concluded that neuronal activity plays a major role in the maintenance of normal NM neurons. Furthermore, these results suggest that transneuronal morphological changes seen in neurons following deafferentation or alterations of sensory experience are a result of changes in the level of presynaptic activity.
Factors Influencing and Steps Leading to the Adoption of Best Management Practices by Louisiana Dairy Farmers

A logistic regression procedure was used to assess the impact of socioeconomic attributes on the best management practices (BMPs) adoption decision by Louisiana dairy farmers relative to cost-share and fixed incentive payments. Analysis of the steps in the BMP adoption decision process indicated visits between producers and the U.S. Department of Agriculture–Natural Resource Conservation Service significantly increase likelihood of BMP adoption. Producer willingness-to-pay results indicate that margin al increases in dairy BMP adoption and associated improvement in environmental quality require increased technical and financial assistance.