cssi/SciSciGPT-SciSciNet huggingface dataset:
Inviscid/boundary layer prediction of aeroheating on a bent-axis biconic

Newly developed inviscid and boundary layer codes are applied to the prediction of aerodynamic heating on both on-axis and bent-axis biconic orbital transfer vehicle configurations proposed by NASA. The inviscid code solves the full three-dimensional form of the nonconservative Euler equations. It features parabolic grid generation and an improved method of characteristics boundary condition. The boundary layer code solves the integral forms of the momentum and energy equations along inviscid streamlines. Generally good agreement is found in comparisons of the inviscid/boundary layer predictions with the experimental data.
Simplest doubly charged negative ion: Nonexistence of H2- resonances

Two independent types of ab initio calculations for three electrons in the field of a proton have been carried out. Neither calculation shows any evidence for the existence of a resonant state of ${\mathrm{H}}^{2\mathrm{\ensuremath{-}}}$ contributing to e+${\mathrm{H}}^{\mathrm{\ensuremath{-}}}$ inelastic scattering, at energies above the three-electron escape threshold. One of the methods used is based on an eigenchannel R-matrix calculation carried out within a reaction volume of finite radius ${\mathit{r}}_{0}$, followed by an averaging procedure over ${\mathit{r}}_{0}$. A second method is based on a configuration-interaction study of the dependence of the 2${\mathit{s}}^{2}$2p $^{2}$${\mathit{P}}^{\mathit{o}}$ resonance on the nuclear charge Z. These calculations suggest that previous experimental and theoretical studies of this system were in erroneous agreement that two $^{2}$${\mathit{P}}^{\mathit{o}}$ resonances exist in ${\mathrm{H}}^{2\mathrm{\ensuremath{-}}}$ above the three-electron escape threshold. We also show that the earlier apparent agreement between experimental and theoretical resonance properties would violate unitarity of the collision matrix.
Focused image recovery from two defocused images recorded with different camera settings

Two new methods are presented for recovering the focused image of an object from only two blurred images recorded with different camera parameter settings. First a blur parameter /spl sigma/ is estimated using one of our two recently proposed depth-from-defocus methods. Then one of the two blurred images is deconvolved to recover the focused image. The first method requires only the knowledge of /spl sigma/ of the camera's point spread function (PSF). It is based on a new spatial domain convolution/deconvolution transform. The second method requires full knowledge of the form of the PSF and is estimated using step edges. The focused image is obtained through deconvolution in the Fourier Domain using the Wiener filter. For both methods, results of experiments on actual defocused images recorded by a CCD camera are presented. The first method requires less computation and gives satisfactory results for up to medium levels of blur. The second method gives good results for up to relatively high levels of blur. >
Preventing Obesity: A Life Cycle Perspective

Traditional approaches to treating overweight and obese adults by focusing on individual weight loss have not been effective in stemming the tide of obesity in the population. Recent research has identified critical factors that, as they accumulate and interact over an individual's life span, may put a person at risk for obesity. These factors include rapid weight gain in infancy and childhood, early puberty, and excessive weight gain in pregnancy. Based on this research, a life cycle perspective can be used to develop comprehensive interventions that address the multiple determinants of obesity. Because obesity tracks across generations, it is essential to adopt effective obesity prevention measures now to prevent even higher rates of obesity in future generations. Dietetics professionals can reduce individual risks by providing nutritional services that support appropriate weight gain in childhood and pregnancy. We can also advocate for policies in communities, schools, and worksites that support breastfeeding, ensure access to health-promoting foods, and provide opportunities to be physically active.
An electron spin resonance study of human epidermal lipids using 5-doxyl stearic acid

Abstract The effect of laurocapram (1-dodecylazacycloheptan-2-one, Azone®) on the lipids of human epidermis was studied by electron spin resonance (ESR) of 5-doxyl stearic acid (5-DSA) intercalated into the epidermis. Order parameters S, polarities ao and S/Wratio (strongly immobilized/weakly immobilized spin label) from the ESR spectra demonstrate that Azone® increased the fluidity and the polarity of the local environment surrounding the spin label, and modified the conformation of epidermal lipid. Skin recovery from the disordered system was observed at a low Azone® concentration. Comparatively, Azone® showed a greater effect on stratum corneum lipid bilayers and a smaller effect on epidermal lipids. There was no direct relationship between the amount of enhancer used and the ESR parameters.
Germination and hyphal growth of vam fungi during and after storage in soil at five matric potentials

Abstract Four vesicular-arbuscular mycorrhizal (VAM) fungi, Cigaspora margarita Decker & Hall, Glomtu mosseae (Nicol. & Gerd.) Gerdemann & Trappe, Glomus intraradices Schenck & Smith, and Acavlospora languid Spain & Schenck. were studied to characterize the variety of responses of VAM fungi to storage. Spores were stored at 23°C for up to 4 months in soil at several matric potentials [Ψ m], then removed and exposed for 1 month in soil at field capacity to induce germination. Each species studied has a different response to storage duration and moisture availability, reflecting the complexity of the problem of storage of VAM fungi in soil. Net germinability, the difference in percentage germination between that which occurred in storage and germination after the subsequent month at field capacity, was effectively zero for Gi. margarita. Hyphae continued to grow and additional germ tubes were produced upon removal from storage. Gi. margarita spores which produced one germ tube per spore during storage in moist soil subsequently produced less root colonization of Paspalum notation than spores stored in drier soil. Net germinability of spores of G. intraradices increased with decreasing storage Ψm and was independent of storage duration. Upon removal from storage, preexisting hyphae resumed growth. Net germinability of spores of G. mosseae was inversely proportional to duration of storage and independent of Ψ m. Spores which germinated in storage did not resume growth upon removal from storage. Net germinability of A. longula increased with duration of storage and was independent of moisture availability during storage, indicating a dormant period.
The Relationships of Health Behaviors to Perceived Stress, Job Satisfaction, and Role Modeling among Health Professionals in South Korea

This study assesses the relationships between health behaviors of health professionals in South Korea and their perceived stress, job satisfaction, and role as positive models of health behaviors. The data were collected using a series of three mailings (n = 207). Based on factor analysis, the following four health behavior constructs were developed as measures of respondents' health behaviors: eating regular meals and fruit, drinking alcohol and smoking cigarettes, eating out and consuming snacks and caffeine, and engaging in regular physical activity and relaxation. Several items were used to measure the perception of stress, job satisfaction, and a role model of positive health behaviors. The results showed significant relationships between health behaviors and health professionals' perceptions on stress, job satisfaction and role modeling (p < .05). The results suggested that practicing positive health behaviors could have an influence on job performance as well as creating positive self-perception of...
Gas sorption and transport in polysulfone

Abstract The sorption and transport of CO2, CH4, Ar, and N2 were measured in a melt-extruded film of polysulfone at 35°C. The results are interpreted in terms of the dual sorption and mobility models and compared to the structurally similar glassy polycarbonate. In addition, sorption measurements were made on specimens with various processing and treatment histories including porous membranes prepared by water coagulation of concentrated polysulfone solutions in DMF and THF. The sorption capacity for CO2 varied considerably with the history of the specimen.
Potential error with in situ surveys of smallmouth bass, Micropterus dolomieu Lacepéde, as determined by radio-telemetry

Abstract In situ surveys using scuba are important tools in the management of smallmouth bass ( Micropterus dolomieu ) in boreal, clear lakes of North America. Population estimates that are derived from such surveys may be erroneous if the size composition of the fish observed by divers differs from that of the entire population. Forty-four adult smallmouth bass of three size classes were radio-tagged and tracked during the summer of 1993 (mid June to early September) in Green Lake, Maine, USA, to investigate possible size-related error from observations by divers being towed along the lake shore. Our results indicate that scuba divers may fail to count a significant portion of large smallmouth bass during late summer (mid July to early September), compared to small- or medium-sized fish. The results suggest that scuba surveys should be conducted during early summer (mid June to mid July) to derive more accurate population estimates.
Problems associated with estimating the relative impact rates on mars and the moon

The lunar cratering rate is known reasonably well from comparison of observed crater frequencies with radiometric ages. Attempts to obtain a cratering rate for Mars have usually been based on calculation of the relative flux of asteroidal and cometary bodies on Mars and the Moon. The asteroidal flux on Mars cannot be obtained in a simple way from the observed number of Mars-crossing asteroids, i.e. those asteroids with perihelia within the orbit of Mars. Calculations of the secular perturbations of these asteroids by several authors, particularly williams, has shown that most of these bodies rarely come near even to Mars' aphelion when they are in the vicinity of the ecliptic plane, and their contribution to the Martian meteoroid flux is much smaller than has been commonly stated. Ring asteroids in the vicinity of the ‘secular resonances’ discovered by Williams, high velocity fragments of asteroids on the inner edge of the asteroid belt, and possibly objects obtained from the 2:1 Kirkwood gap by a process described by Zimmerman and Wetherill are probably of greater importance in the 103-106 g meteoroid size range but are much less important in the production of large craters. Calculations of the Martian asteroidal and cometary impact rate are made, but the present unavoidable uncertainties in the results of these calculations result in their being of little value in establishing a Martian chronology. Suggestions for improving this situation are discussed.
Interfaces of polymeric precursors with ceramics/metals

Preceramic polymers that yield ceramic materials on heating have been investigated as precursors to fibers, binders, powders, and coatings. These materials have also been used as processing additives for ceramics, rheological control agents, and aids for controlling the microstructure of ceramics and coatings. The reactivity of the precursors with ceramic and metal powders or with substrate surfaces opens up many possibilities for improved processing of materials, fabrication of novel materials, and the preparation of materials and coatings with improved properties. Although reactions at interfaces between polymeric precursors and ceramics or metals are not yet well understood, the beneficial effects of using precursors have been demonstrated. Interfacial reactions between polymers and other materials depend on the polymer composition and rheological properties, the ceramic or metallic material composition and surface states, and the heat treatments and environments. Interfaces range from relatively simple interfaces between a pure polymer-derived material and a substrate, as reflected by the formation of coatings or the use of polymers to infiltrate porous materials, to complex interfaces between polymers, various powders, and occasionally substrates. Examples of complex interactions include the use of precursors as binders or microstructural control agents and the direct formation of bulk materials or matrix materialsmore » from polymer/powder compositions. This paper gives specific examples of the interactions of polymeric precursors with ceramics to provide controlled microstructure development during sintering of Si[sub 3]N[sub 4] (in-situ growth of elongated grains) and to form near-net-shape mullite and mullite-based coatings with unique properties.« less
Fluorescence studies with DNA probes: dynamic aspects of DNA structure and DNA-protein interactions

Time-resolved fluorescence measurements of optical probes incorporated at specific sites in DNA provides a new approach to studies of DNA structure and DNA:protein interactions. This approach can be used to study complex multi-state behavior, such as the folding of DNA into alternative higher order structures or the transfer of DNA between multiple binding sites on a protein. In this study, fluorescence anisotropy decay of an internal dansyl probe attached to 17/27-mer oligonucleotides was used to monitor the distribution of DNA 3' termini bound at either the polymerase of 3' to 5' exonuclease sites of the Klenow fragment of DNA polymerase I. Partitioning of the primer terminus between the two active sites of the enzyme resulted in a heterogeneous probe environment, reflected in the associative behavior of the fluorescence anisotropy decay. Analysis of the anisotropy decay with a two state model of solvent-exposed and protein-associated dansyl probes was used to determine the fraction of DNA bound at each site. We examined complexes of Klenow fragment with DNAs containing various base mismatches. Single mismatches at the primer terminus caused a 3-fold increase in the equilibrium partitioning of DNA into the exonuclease site, while two or more consecutive G:G mismatches caused the DNA to bind exclusively at the exonuclease site, with a partitioning constant at least 250- fold greater than that of the corresponding matched DNA sequence. Internal single mismatches located up to four bases from the primer terminus produced larger effects than the same mismatch at the primer terminus. These results provide insight into the recognition mechanisms that enable DNA polymerases to proofread misincorporated bases during DNA replication.
Treatment of isolated injuries of the lunotriquetral ligament

We studied 57 patients with isolated lunotriquetral injuries treated by arthrodesis, direct ligament repair, or ligament reconstruction. The outcomes were compared by using written questionnaires, the Disabilities of the Arm, Shoulder and Hand (DASH) score, range of movement, strength, morbidity and rates of reoperation. Isolated lunotriquetral injury was confirmed by arthroscopy or arthrotomy. The mean age of the patients was 30.7 years (15.4 to 53.7) and the injuries were subacute or chronic in 98.2%. Eight patients underwent lunotriquetral reconstruction using a distally-based strip of the tendon of extensor carpi ulnaris, 27 had lunotriquetral repair and 22 had lunotriquetral arthrodesis. The mean follow-up was 9.5 years (2 to 22). The probability of remaining free from complications at five years was 68.6% for reconstruction, 13.5% for repair, and less than 1% for arthrodesis. Of the lunotriquetral arthrodeses, 40.9% developed nonunion and 22.7% developed ulnocarpal impaction. The probability of not requiring further surgery at five years was 68.6% for reconstruction, 23.3% for repair and 21.8% for arthrodesis. The DASH scores for each group were not significantly different. Objective improvements in strength and movement, subjective indicators of pain relief and satisfaction were significantly higher in the lunotriquetral repair and reconstruction groups than in those undergoing arthrodesis.
Quantitative restrictions and tariffs with endogenous firm behavior

Abstract This paper considers a foreign oligopoly which dominates an importing country's market with its exports of differentiated products. It constructs a model where firm behavior is endogenously determined in an infinitely repeated game and it analyzes the impact of trade policies on market conduct and welfare. Optimal tariffs, optimal quotas and optimal tariff-quotas are characterized and compared. One result is that quotas can enhance competition and increase welfare. Another result is that quotas can be superior to tariffs. Finally, optimal tariff-quotas are welfare superior to either tariffs or quotas alone.
Online student evaluations of hospitality professors: A cross-cultural comparison

Abstract With the popularity of RateMyProfessors.com and similar online teacher-rating websites, research on online student evaluation issue has generated valuable results. Online data form a better research source for cross-cultural research than traditional survey data. Using data collected from two online teacher-rating websites: RateMyProfessors.com and PingLaoShi.com, the current study conducted cross-cultural comparisons of online student evaluations of hospitality professors in two countries, the United States and China. Twenty-one U.S. universities and 18 Chinese universities were selected, resulting in 469 professors in the U.S. and 646 professors in China. The results of multiple regressions showed that interest was the most important factor influencing overall quality of professors for both countries. However, the effects of easiness and gender on the overall quality were totally different across the two countries. The study then provided suggestions regarding hospitality education improvement in two countries.
Minireview : Obesity and LipOdystrophy-Where Do the Circles Intersect?

Adipose tissue is unique in that it can undergo significant hypertrophy and atrophy, resulting in wide ranges of obesities and lipodystrophies. At the base of this elasticity is the lipid-filled adipocyte, which can either overfill by storing large amounts of triglycerides or shrink to a tiny cell by depleting its lipids and as such is remarkable in sustaining insults. As a major energy reservoir, the adipocyte may hold considerable calories necessary for survival and reproduction, two functions that are essential for the survival of the species. This review will summarize some of the recent studies that have advanced our understanding of the central and peripheral mechanisms that are initiated by adipocyte-secreted factors such as leptin, adiponectin, resistin, and retinol-binding protein 4. The intersection of obesity and lipodystrophy results in insulin resistance, which may be unlocked by elucidating the roles of these factors in pathways that control insulin sensitivity and glucose uptake.
The question of a pressure effect in the reaction OH + CO at room temperature☆

Abstract Absolute rate constants for the reaction of OH with CO were determined at 296 ± 2 K, with 50 torr of He and 0–350 torr of SF6. The rate constant was found to change from ≈1.0 × 1011 to ≈1.9 × 1011 cm3 mol−1 s−1 depending on the pressure and nature of the third body M, in agreement with our earlier results and with the three studies by Heicklen, Cox, Calvert, and their co-workers. However, it is not possible, at present, to attribute the effect with certainty to any particular cause.
Dynamics within mutualism and the maintenance of diversity: inference from a model of interguild frequency dependence

Numerical models have suggested that the dynamics within mutualisms are not important for the maintenance of diversity. In this study it is demonstrated that the dynamics within mutualism can contribute to the maintenance of diversity within its participants, using a general model of frequency dependence between two mutualistically interacting guilds. Specifically, it is demonstrated that while mutualisms may exhibit positive feedback in density, there may be a negative feedback within a mutualism as a result of the change in composition within the interacting guild. Such a negative feedback results from an asymmetry in the delivery of benefit between participants of the mutualism that generates a negative interguild frequency dependence. This dynamic contributes to the maintenance of diversity within the interacting guilds. Conditions are identified for the maintenance of diversity and the maximization of benefit from mutualism within the context of the model. The utility of these conditions for testing hypotheses using data from the mutualistic interaction between plants and mycorrhizal fungi is then demonstrated.
The interactions of 1,4-dihydropyridines bearing a 2-(2-aminoethylthio)methyl substituent at voltage-dependent Ca+ channels of smooth muscle, cardiac muscle and neuronal tissues

The Ca2+ channel antagonistic potencies of tiamdipine [2-(2-aminoethylthio)methyl-3-carboethoxy-5-carbomethoxy-6-methyl-4-(3-nitrophenyl)-1,4-dihydropyridine] and nifedipine [2,6-dimethyl-3,5-dicarbomethoxy-4-(2nitrophenyl)-1,4-dihydropyridine] analogs bearing phenyl ring substituents were studied using pharmacologic and radioligand binding techniques. Additionally, analogs of tiamdipine possessing (2-aminoethylthio)methyl-, (2-acetamidoethylthio)methyl-and (2-pyrrolidinylmethylthio)methyl-groups at the C2 position of the 1,4-dihydropyridine ring have been studied.
The Effects of Fumonisin B1 on viability and mitogenic response of avian immune cells

Fumonisin B1 (FB1) is a mycotoxin produced by the fungus Fusarium verticillioides (formerly Fusarium moniliforme) and is found in diverse crops such as corn, wheat, and barley. Many diseases linked to FB1, such as porcine pulmonary edema, rat hepatic cancer, and equine leukoencephalomalacia, indicate a compromised immune system. The purpose of this study was to determine whether FB1 altered immunological responses in various cell populations of Single Comb White Leghorn chicks. Cells collected for this study were obtained from those immunological organs with well-defined responses (i.e., spleen, thymus, and blood). Cell populations were exposed to 5 to 50 microg/mL FB1 in vitro for 24 to 72 h, and viability and mitogenic response were evaluated. The effects of FB1 on the mitogenic response were evaluated in cell populations from the spleen and blood stimulated with the mitogens, lipopolysaccharide, concanavalin A, and pokeweed mitogen and in thymocytes stimulated with concanavalin A. The 3-(4,5-dimethylthazol-2-yl)-diphenyl-2H-tetrazolium bromide (MTT) reduction assay was used to assess viability and mitogenic response. Fumonisin B1 decreased spleen cell viability and mitogenic response, albeit the degree of decrease varied with mitogen and time of exposure. Fumonisin B1 increased number of viable thymic cells at 50 microg/mL but had no effect on the mitogenic response of thymocytes. Fumonisin B1 had no effect on blood lymphocyte viability or mitogenic response.
The flagellation and taxonomy of species of Acetobacter.

TheAcetobacter genus as presently constituted include two distinctly different morphological types, one having peritrichous flagella with a wavelength averaging 2.9 μ and the other having polar multitrichous flagella with a wavelength averaging 1.4 μ. All of the peritrichously flagellated types actively oxidized acetic and lactic acids to CO2 and H2O, while none of the polar flagellated types showed this property. It is proposed that the presentAcetobacter genus be divided into two genera:Acetobacter andAcetomonas gen.nov. The redefinedAcetobacter genus should include only peritrichously flagellated species and nonflagellated species with similar physiology.Acetomonas gen. nov. should include only polar multitrichous species and nonflagellated species of similar physiology. Typical species of the redefinedAcetobacter genus should oxidize acetic or lactic acid to CO2 and H2O while typical species ofAcetomonas gen. nov. should not have this property.
Herstellung und synthetische Verwendung von metallierten Dimethylhydrazonen Regio‐ und stereoselektive Alkylierung von Carbonylverbindungen

Dimethylhydrazone (DMH's) 6–10 von enolisierbaren Aldehyden und Ketonen konnen mit n-Butyllithium und/oder Lithium-diisopropylamid in Tetrahydrofuran quantitativ in α-Stellung metalliert werden. Die so erhaltenen Lithiumderivate 11–14 sind hochreaktive Kohlenstoffnucleophile. Ihre Verwendung als Enolataquivalente wird uber die Sequenz Carbonylverbindung, DMH-Derivat. Metallierung, Reaktion mit Alkylhalogeniden (→ 16, 18, 19) und Spaltung zur α-substituierten Carbonylverbindung (17) an einer Anzahl von Beispielen demonstriert. Die Alkylierungen erfolgen, von Spezialfallen abgesehen, regiospezifisch am weniger substituierten Kohlenstoffatom. Cyclohexanonderivate werden stereoselektiv axial alkyliert, was zur Darstellung von trans-disubstituierten Cyclohexanonen ausgenutzt wird. Zur quantitativen Spaltung der Dimethylhydrazone zuruck zu den Carbonylverbindungen unter milden Bedingungen (pH 7, Raumtemperatur) wurde eine neue oxidative Hydrolyse entwickelt. Die Vorteile der Methode werden kurz diskutiert.
Structure and Kinetics of PTEN Tumor Suppressor Association with Lipid Membranes

PTEN is the second most commonly mutated protein in human cancer [1]. The PTEN-PI3K phosphorylation switch regulates cell growth and survival by controlling the levels of PI(3,4,5)P3 in the plasma membrane. PTEN's association with the membrane is critical for bringing its active site in close proximity to the substrate, PI(3,4,5)P3. The crystal structure of a truncated PTEN was determined [2], however, the structure of membrane-bound PTEN remains unknown. In this work, we perform systematic binding studies of PTEN with membranes and report first steps toward a structural characterization of PTEN associated with bilayers.We compared the binding affinities of wt PTEN, the truncated PTEN [2] and two point mutants, C124S and H93R, to lipid membranes with various anionic lipid (PS, PI(4,5)P2 and PI(3,4,5)P3) compositions using Surface Plasmon Resonance (SPR). PS and PI(4,5)P2 show strong cooperativity in binding to wt PTEN while PI(4,5)P2 and PI(3,4,5)P3 show independent binding to the catalytically inactive C124S mutant. The H93R mutation is spatially separated from the active site as well as the membrane binding motifs, yet results in altered affinities to PS and PI(4,5)P2. The truncated PTEN mutant has an increased affinity to PS-containing membranes over wt PTEN due to an increase in its net positive charge. Neutron reflectivity (NR) experiments were performed to characterize the structure of the PTEN-membrane complex. We observe minimal penetration of the proteins into the lipid headgroup region, indicating that protein association occurs only with the membrane surface. Small, yet significant differences in the NR profiles emphasize the role the point mutations have in altering PTEN's association with the membrane. Molecular dynamics and coarse-grained simulations are currently being performed to interpret structural and orientational details in the NR data.[1] Nature (2006) 441, 424-430.[2] Cell (1999) 99, 323-334.
Development and verification of general correlations for pressure drop and heat transfer in single-phase turbulent flow in enhanced tubes

General correlations are developed and verified for friction factor and heat-transfer coefficient for single-phase turbulent flow in internally augmented tubes. Data from frequently referred investigations were gathered for a wide range of tube parameters with ed, 0.01 to 0.2; pd, 0.1 to 7.0; α90, 0.3 to 1.0, and flow parameters Re, 5000 to 250,000 and Pr, 0.66 to 37.6. The data were applied to a linear model to obtain normalized correlations that were then modified to approach smooth tube correlation as the roughness variables became very small. A shape function was included in the friction correlation to account for different rib profiles. These correlations were then verified by independent experiments. Different types of commercial ribbed tubes were tested with water as working fluid under heating conditions. Five wire coil inserts were tested in another apparatus using air under cooling conditions. The parameters tested were Re = 5000–60,000, ed = 0.023–0.127, pd = 0.12–1.17, and α90 = 0.34–0.91. The results proved that the correlations can be successfully applied to a wide range of roughness types and Prandtl number. The present correlations are superior, for this large database, to those presented by other investigators. The friction factor correlation predicts 96% of the database to within ±50% and 77% of the database to within ±20%. Corresponding prediction figures for the heat-transfer correlation are 99 and 69%.
On the stress/parasuicide or parasuicide/stress relationship

The question of whether high stress leads to attempting suicide (parasuicide) or suicide attempters are more likely to report high stress was examined in a one-year follow-up study of 98 persons, 47 of whom had attempted suicide. Cross-lagged panel correlations between stress and parasuicide provided both concurrent and predictive validity that stress as measured by life changes leads to parasuicide. A high relationship between stress at baseline and stress at follow-up provided support for the notion that some individuals experience chronic stress and that such individuals may be the ones at risk for future suicide attempts.
Molecular Mechanisms of Photoaging and its Prevention by Retinoic Acid: Ultraviolet Irradiation Induces MAP Kinase Signal Transduction Cascades that Induce Ap-1-Regulated Matrix Metalloproteinases that Degrade Human Skin In Vivo

Ultraviolet radiation from the sun damages human skin, resulting in an old and wrinkled appearance. A substantial amount of circumstantial evidence indicates that photoaging results in part from alterations in the composition, organization, and structure of the collagenous extracellular matrix in the dermis. This paper reviews the authors' investigations into the molecular mechanisms by which ultraviolet irradiation damages the dermal extracellular matrix and provides evidence for prevention of this damage by all-trans retinoic acid in human skin in vivo. Based on experimental evidence a working model is proposed whereby ultraviolet irradiation activates growth factor and cytokine receptors on keratinocytes and dermal cells, resulting in downstream signal transduction through activation of MAP kinase pathways. These signaling pathways converge in the nucleus of cells to induce c-Jun, which heterodimerizes with constitutively expressed c-Fos to form activated complexes of the transcription factor AP-1. In the dermis and epidermis, AP-1 induces expression of matrix metalloproteinases collagenase, 92 kDa gelatinase, and stromelysin, which degrade collagen and other proteins that comprise the dermal extracellular matrix. It is hypothesized that dermal breakdown is followed by repair that, like all wound repair, is imperfect. Imperfect repair yields a deficit in the structural integrity of the dermis, a solar scar. Dermal degradation followed by imperfect repair is repeated with each intermittent exposure to ultraviolet irradiation, leading to accumulation of solar scarring, and ultimately visible photoaging. All-trans retinoic acid acts to inhibit induction of c-Jun protein by ultraviolet irradiation, thereby preventing increased matrix metalloproteinases and ensuing dermal damage.
Differences in oxidative stress status and expression of MKP-1 in dorsal medulla of transgenic rats with altered brain renin-angiotensin system

ANG II-stimulated production of reactive oxygen species (ROS) through NADPH oxidase is suggested to activate MAPK pathways, which are implicated in neurally mediated pressor effects of ANG II. Emerging evidence suggests that ANG-(1–7) up regulates MAPK phosphatases to reduce MAPK signaling and attenuate actions of ANG II. Whether angiotensin peptides participate in long-term regulation of these systems in the brain is not known. Therefore, we determined tissue and mitochondrial ROS, as well as expression and activity of MAPK phosphatase-1 (MKP-1) in brain dorsal medullary tissue of hypertensive transgenic (mRen2)27 rats exhibiting higher ANG II/ANG-(1–7) tone or hypotensive transgenic rats with targeted decreased glial expression of angiotensinogen, ASrAOGEN (AS) exhibiting lower ANG II/ANG-(1–7) tone compared with normotensive Sprague-Dawley (SD) rats that serve as the control strain. Transgenic (mRen2)27 rats showed higher medullary tissue NADPH oxidase activity and dihydroethidium fluorescence in isolated mitochondria vs. SD or AS rats. Mitochondrial uncoupling protein 2 was lower in AS and unchanged in (mRen2)27 compared with SD rats. MKP-1 mRNA and protein expression were higher in AS and unchanged in (mRen2)27 compared with SD rats. AS rats also had lower phosphorylated ERK1/2 and JNK consistent with higher MKP-1 activity. Thus, an altered brain renin-angiotensin system influences oxidative stress status and regulates MKP-1 expression. However, there is a dissociation between these effects and the hemodynamic profiles. Higher ROS was associated with hypertension in (mRen2)27 and normal MKP-1, whereas the higher MKP-1 was associated with hypotension in AS, where ROS was normal relative to SD rats.
Interfacial Fracture Phenomena in Ceramic Composite Directionally Solidified Eutectics with a Ductile Interphase

Interphase interfaces in NixCo1−xO/ZrO2(CaO) directionally solidified eutectics (DSEs) are modified by selective chemical reduction of the NixCo1−xO oxide phase. Scanning electron microscopy studies of such NixCo1−xO/ZrO2(CaO) DSEs show formation of a thin layer of metallic Ni(Co) interphase (∼100 nm) and interfacial porosity upon reduction at high temperatures. A significant change is observed in the mechanical behavior of the reduced NixCo1−xO/ZrO2(CaO) DSEs compared with its pristine counterpart, which is largely attributed to the formation of metallic Ni(Co) interphases. Indentation fracture studies indicate that the presence of metallic interphases in the DSEs enhance the stress energy release mechanism through plastic deformation, interfacial delamination, crack arrest, and crack bridging across the metallic interphase after reduction.
Efficiency of electrochemical systems

The second-law efficiency is proposed for measuring and comparing the performance of electrochemical processes. It measures how close the process approaches a reversible process. Other definitions of efficiency found in the literature based on the first law of thermodynamics can generate efficiency values that are >100% for certain systems depending on whether the change in entropy for the overall chemical reaction involved in the process is positive or negative. Such efficiency values are misleading while making it difficult to compare processes that absorb or release significant quantities of thermal energy. Use of the proposed efficiency which is within the frame work of the second law of thermodynamics, can reach 100% only in the limit of a reversible process and will always stay <100% whether the entropy change is positive or negative. Furthermore, it accounts for the quality of thermal energy added to or removed from the system and thus provides a more consistent way of comparing different types of electrochemical devices. This consistency will allow better comparison of performance on a widespread basis, i.e., between groups working on distinct electrochemical systems.
But dictionaries are data too

Although empiricist approaches to machine translation depend vitally on data in the form of large bilingual corpora, bilingual dictionaries are also a source of information. We show how to model at least a part of the information contained in a bilingual dictionary so that we can treat a bilingual dictionary and a bilingual corpus as two facets of a unified collection of data from which to extract values for the parameters of a probabilistic machine translation system. We give an algorithm for obtaining maximum likelihood estimates of the parameters of a probabilistic model from this combined data and we show how these parameters are affected by inclusion of the dictionary for some sample words.
Topics in data assimilation: Stochastic processes

Abstract Stochastic models with varying degrees of complexity are increasingly widespread in the oceanic and atmospheric sciences. One application is data assimilation, i.e., the combination of model output with observations to form the best picture of the system under study. For any given quantity to be estimated, the relative weights of the model and the data will be adjusted according to estimated model and data error statistics, so implementation of any data assimilation scheme will require some assumption about errors, which are considered to be random. For dynamical models, some assumption about the evolution of errors will be needed. Stochastic models are also applied in studies of predictability. The formal theory of stochastic processes was well developed in the last half of the twentieth century. One consequence of this theory is that methods of simulation of deterministic processes cannot be applied to random processes without some modification. In some cases the rules of ordinary calculus must be modified. The formal theory was developed in terms of mathematical formalism that may be unfamiliar to many oceanic and atmospheric scientists. The purpose of this article is to provide an informal introduction to the relevant theory, and to point out those situations in which that theory must be applied in order to model random processes correctly.
Multiscale Modeling of Flood-Induced Piping in River Levees

A three-dimensional transient fully coupled fluid-particle model is utilized to simulate flood-induced piping under river levees and taking into account the effects of soil-fluid-structure interactions. The porous soil medium is modeled as a mixture of two phases, namely the fluid phase (water) and the particulate solid phase. The fluid is idealized as a continuum by using an averaged form of Navier–Stokes equations that accounts for the presence of the solid particles. These particles are modeled at a microscale using the discrete element method. The interphase momentum transfer is modeled using an established relationship that accounts for the dynamic change in porosity and possible occurrence of nonlinear losses. The hydraulic structure (levee) is modeled as an impervious rigid block and its motion is described by a combination of external and internal forces from the surrounding fluid and solid particles. A computational simulation is conducted to investigate the response of a granular deposit when su...
Finite-temperature chiral transition in real-world QCD?

Abstract I present and discuss the first physics results of a Langevin simulation of finite-temperature QCD with a realistic current quark spectrum. Up to several caveals which will need to be addressed by future studies, our present results suggest that there is a first-order chiral restoration phase transition in real-world QCD, that it is driven by the light condensate and that it should be accompanied by a partial restoration of U (1) A symmetry.
Tillage × Maize Hybrid Interactions

Continuous maize (Zea mays L.) yields may be depressed with no-tillage (NT) compared with conventional chisel and disking systems (CD). Shallow or deep in-row tillage (ST and DT, respectively) may help alleviate this yield reduction, whereas some hybrids may be better adapted to NT. We therefore evaluated five maize hybrids with NT, ST, DT, and CD from 2002 to 2004 on a Hagerstown silt loam (fine, mixed, semiactive, mesic Typic Hapludalf) in southeastern Pennsylvania. Residue cover, penetration resistance, bulk density, and soil temperature were measured as well as maize emergence, mid-season height, and yield. Residue cover varied in the order NT > ST and DT > CD. Bulk density and penetration resistance in NT were higher than in ST, DT, and CD to the depth of tillage. In 2002, the average soil temperature during the first month after planting varied in the order NT < ST and DT < CD, but did not vary between tillage systems in 2004. Emergence was slower in NT than the other tillage systems in 2002 only. Emergence varied between hybrids, but there was no tillage × hybrid interaction. Mid-season maize height was not lower in NT than the other tillage systems. Tillage systems did not affect yield, and there was no tillage × hybrid interaction for yield, although some hybrids yielded better than others. The study suggests continuous maize yields with NT will be similar to tilled systems on well-drained soils in the northeastern USA and that tillage system is not important for hybrid selection.
Application of Lévy Mutation Operator in Evolutionary Programming Optimization of Antennas

In this paper, we discuss the implementation of Evolutionary Programming (EP) using a mutation operator based on Levy probability distribution and investigate its performance in optimization of selected antenna problems. Since the shape-parameter, alpha, in the Levy distribution results in Cauchy and Gaussian distributions for values of 1 and 2, respectively, one can design adaptive schemes that dynamically change the shape of Levy distribution in generation of offsprings during the evolutionary process in order to exploit the desirable properties of these two distributions. In particular, we introduce a simple adaptive scheme and compare its performance in antenna optimization to adaptive and non-adaptive schemes, previously reported in the literature.
Superresolution Investigation of In Vivo Structure and Dynamics of E. coli FtsZ Structures during Cytokinesis

Control of E. coli cell division is achieved by a network of proteins that organize cytokinesis in space and time. FtsZ, a tubulin-like GTPase that forms head-to-tail protofilaments, localizes to the midcell and assembles into a ring-like structure known as the Z-ring. The Z-ring serves as an essential scaffold to recruit all other division proteins and generates contractile force for cytokinesis, but its supramolecular structure and contraction mechanism remain unknown. We have used photoactivated localization microscopy (PALM) to characterize the in vivo structural dynamics of the Z-ring in E. coli at a spatial resolution of ∼35 nm.Superresolution imaging revealed that the Z-ring is ∼110nm wide and is composed of a loose 3D bundle of FtsZ protofilaments that overlap with each other in both the longitudinal and radial directions in the cell. These 110nm rings were observed in either a single-ring conformation at midcell or in a multiple-ring conformation reminiscent of a tight helix. The tight helix conformation was very rarely observed in cells with a visible septation, suggesting that the Z-ring fluctuates between the single-ring and tight helix conformation before cytokinesis begins, but then adopts only the single-ring conformation during constriction. We also observed non-ringlike FtsZ structures emanating from the midcell in cells at later stages of constriction, indicating Z-ring disassembly. These disassembling structures were observed in cells with 200-600nm septum diameters, suggesting that Z-ring disassembly occurs gradually throughout the constriction process. We also observed that the bandwidth distribution of the Z-ring did not change with varying expression levels, cell size, or during the progression of cytokinesis, suggesting that the factors that regulate Z-ring thickness are not affected by FtsZ concentration or changes in cell shape.
Characterization and quantification of Bcl-2 antisense G3139 and metabolites in plasma and urine by ion-pair reversed phase HPLC coupled with electrospray ion-trap mass spectrometry.

Abstract A novel ion-pair reversed phase electrospray ionization (IP-RP-ESI) liquid chromatography–mass spectrometry (LC–MS) method has been developed for identification and quantification of Bcl-2 antisense phosphorothioate oligonucleotides G3139 and metabolites in plasma. This method utilized solid phase extraction for desalting and matrix removal and detection by an ion trap mass spectrometer. Resolution was accomplished on a micro C18 column eluted with a mobile phase consisting of hexafluoro-2-propanol and triethylamine in methanol at 50 °C. Five G3139 metabolites were identified in plasma and urine from treated patients and rats. A cassette HPLC–MS/MS quantification method for G3139 and three metabolites was developed and validated with a limit of quantification (LOQ) of 17.6 nM in human and rat plasma with acceptable precision and accuracy. Plasma pharmacokinetics of G3139 and metabolites in these species were described.
A survey to determine the occurrence of Histoplasma capsulatum and Cryptococcus neoformans in air-conditioners.

A survey of 84 dust samples from 42 air-conditioners and controls was conducted at Kansas State University, Manhattan. Isolations ofC. neoformans andH. capsulatum were attemped using various mycological procedures.
Determinants of Democracy in the Muslim World

This article, which examines the factors and processes that account for the negative correlation between Muslim majority states and democratization, focuses on the institutionalization of Islam in the state. I assess the effect of this factor along with other determinants on regime type from 1990 to 2002 in the population of fifty-one Muslim-majority states, using a multilevel mixed effects linear regression model and path analysis. The analysis shows that although Islam is arguably the most conspicuous factor characterizing this set of states, the institutionalization of Islam in the state is not an impediment to democratization. Instead, factors particularly associated with the Middle East and North Africa, as well as a communist legacy, delay meaningful democratic reform. The results of various regression models suggest that the states in this region with a better propensity toward democratic change are Egypt, Jordan, Tunisia, and Yemen.
ATP sulphurylase activity of the nodP and nodQ gene products of Rhizobium meliloti

THE symbiotic bacterium Rhizobium meliloti stimulates alfalfa (Medicago sativa L.) roots to undergo morphogenesis and form nitrogen-fixing nodules. It has been proposed that the bacterial genes nodABC, common to all Rhizobium, are required for synthesis of an oligosaccharide factor, which is converted to a sulphated form (NodRm-1) by the products of the R. meliloti-specific genes nodH and nodQ1–5; NodRm-1 elicits host-specific plant responses2. Previously we have shown that the nodP gene is homologous to a segment of the Escherichia coli genome6; when we cloned this E. coli fragment we found that it mapped near 59 minutes, corresponding to the cysDNC locus. The genes cysD and cysN encode proteins that catalyse the synthesis of adenosine 5′-phosphosulphate, the first step in the activation of inorganic sulphate7. Here we demonstrate that nodP and nodQ correspond to cysD and cysN, and that their proteins have ATP sulphurylase activity both in vivo and in vitro. We propose that nodP and nodQ synthesize an activated sulphate that is an intermediate in the formation of the alfalfa-specific sulphated nodRm-1 factor.