cssi/SciSciGPT-SciSciNet huggingface dataset:
Biopsychosocial mechanisms associated with tobacco use in smokers with and without serious mental illness.

Abstract Smokers with serious mental illness (SMI) are less responsive to cessation treatments than those without SMI. In this study, we compared smokers with and without SMI on validated measures of biological and psychosocial factors associated with tobacco use. Smokers with (n = 58) and without SMI (n = 83) who were enrolled in parallel clinical trials were compared on measures of carbon monoxide (CO) exposure, nicotine exposure, tobacco-specific nitrosamine exposure, craving, smoking motives, affect, perceived stress, environmental exposure to smoke/smokers, respiratory symptoms, tobacco-related health risk perceptions, and whether they had received recent advice to quit smoking from a health care provider. Data were collected between 2013 and 2017 in Providence, Rhode Island, USA. Samples were compared using independent-sample t-tests and chi-squared tests. Smokers with SMI had higher CO, nicotine, and tobacco-specific nitrosamine exposure levels, greater cigarette dependence, higher craving, and higher scores on eight out of eleven smoking motives (p's
Predictors of Self-Reported Burnout Among Radiology Faculty at a Large Academic Medical Center.

Abstract Objective Determine predictors of self-reported burnout among academic radiologists. Methods In 2017, radiologists at an urban medical center completed the Stanford Wellness Survey, rating burnout via Likert scale (0: no burnout; 1: occasional stress, no burnout; 2: one or more burnout symptoms; 3: persistent burnout symptoms; 4: completely burned out). Univariate analyses assessed age, gender, family situation, clinical versus research focus, and academic rank for association with burnout (Likert scale ≥ 2). Responses in 11 domains querying definitions of burnout (professional fulfillment, emotional exhaustion, interpersonal disengagement), individual factors (sleep-related impairment, self-compassion, negative work impact on personal relationships), institutional factors (perceived appreciation, control over schedule, organizational or personal values alignment, electronic health record experience, supervisor’s leadership quality) were evaluated for association with burnout, using χ2 and logistic regression to calculate odds ratios (ORs). Results In 159 of 204 (77.9%) completed radiologist surveys, 35.2% (56 of 159) reported burnout. Age Discussion Nearly all questions significantly predicted self-reported burnout, observed in over one-third of academic radiologists. Younger age and clinical focus were associated with burnout. Initiatives targeting individual factors (eg, sleep impairment, self-compassion) and institutional factors (eg, physician appreciation, leadership-faculty interactions) may reduce burnout.
Exploring Evolution in Action in the Classroom, through Human Genetic Diversity and Patterns

This chapter outlines the difficulty and importance of tackling human evolution in the classroom, and the different demands this places on the instructor. It discusses lessons for teaching evolution in action, specifically in the context of human evolution and population genetics. These lessons include explicit hands-on activities for the students in analyzing and interpreting human genetic data, and addressing the information flow from scientific journal articles to popular presentation in the media. This content was implemented in a course designed for graduate students though with the occasional advanced undergraduate student with background in STEM fields other than biology. The chapter finally reflect on what the students gain from these lessons, and what limitations remain.
Self-Assembled Peptide-Based Biocomposites for Near-Infrared Light Triggered Drug Release to Tumor Cells

Peptide-based nanomaterials are increasingly gaining popularity due to their specificity, biocompatibility, and biodegradability. In this work, a new multi-layered peptide-based biocomposite for targeting MCF-7 breast cancer cells is developed. The amphipathic Fluorenylmethyloxycarbonyl (Fmoc)-Leu-Ser peptide is synthesized, which is conjugated to a tumor-targeting peptide sequence Gly-Cys-Gly-Asn-Ser to form Fmoc-L-S-G-C-G-N-S (FLS) assemblies. To the FLS assemblies, gold nanorods are then attached to develop drug delivery vehicles (DDVs). The DDVs are entrapped with the anti-cancer drug fulvestrant. Entrapment efficiency is found to be 50.6%. Release studies indicate that irradiating the gold nanorod bound DDVs at NIR wavelength (785 nm) increases drug release by fourfold compared to assemblies that are not irradiated. These results also show higher cytotoxicity and lower cell invasion due to photo-triggered drug release. Furthermore, distinct actin cytoskeletal changes are observed. Such novel peptide-based gold nanorod bound DDVs demonstrate potential in dual targeting of MCF-7 breast cancer cells.
Attention to misleading and contentious tweets in the case of Hurricane Harvey

The spread of false and misleading information through online social media is an elevated concern in emergency contexts such as natural disasters, where the on-the ground decision-making window is shorter, and the stakes can be particularly high. Misinformation that gets attention and is drawn out longer during and after such disasters potentially puts the affected population at additional risk. This research focuses on popular but ambiguous and contentious narratives transmitted via Twitter during Hurricane Harvey. Two most talked about contentious narratives consisted of (1) government agencies putting undocumented immigrants at risk and (2) decisions about evacuation. They depict the process of debunking, competing narratives, and political ideology that have kept the stories alive. Our findings suggest the following: that government and reporters play important roles in stemming the spread of contentious or false information; ambiguous and contentious narratives remain in the conversation longer, specific debunking works faster and reaches a larger audience than general or confused debunking; and the lack of coordination of messaging online and on the ground as well as among different government agencies may threaten the timely and accurate delivery of disaster responses.
CRISPR People: The Science and Ethics of Editing Humans

People have been talking about human germline genome modification for decades, though without necessarily using those words. More than 15 years ago, I reviewed two books about changing a human's DNA in ways that would get into the eggs or sperm and possibly be passed down to future generations, 1 but even then, the debate had been raging for decades. This chapter looks at those discussions up to the disclosure of He's experiment, in two parts: the early discussions of recombinant DNA technology, notably at the famous Asilomar Conference, and the more focused discussions after the development of CRISPR as a genome editing system. Along the way, it takes a look at some of the people, "CRISPR people," although not "CRISPR'd people," who were involved.
Is it Worth it? Postsecondary Education and Labor Market Outcomes for the Disadvantaged

In this paper we examine a range of postsecondary education and labor market outcomes, with a particular focus on minorities and/or disadvantaged workers. We use administrative data from the state of Florida, where postsecondary student records have been linked to UI earnings data and also to secondary education records. Our main findings can be summarized as follows:1) Gaps in secondary school achievement can account for a large portion of the variation in postsecondary attainment and labor market outcomes between the disadvantaged and other students, but meaningful gaps also exist within achievement groups, and 2) Earnings of the disadvantaged are hurt by low completion rates in postsecondary programs, poor performance during college, and not choosing high-earning fields. In particular, significant labor market premia can be earned in a variety of more technical certificate and Associate (AA) programs, even for those with weak earlier academic performance, but instead many disadvantaged (and other) students choose general humanities programs at the AA (and even the Bachelor’s or BA) level with low completion rates and low compensation afterwards.A range of policies and practices might be used to improve student choices as well as their completion rates and earnings.
Impact of Assimilating the Special Radiosonde Observations on COAMPS Arctic Forecasts During the Year of Polar Prediction

We quantify the impact of assimilating the extra radiosonde observations launched in August 2018 during the Year of Polar Prediction (YOPP) on numerical weather prediction forecasts over the Arctic using the U.S. Navy's Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS®). The Naval Research Laboratory Atmospheric Variational Data Assimilation System (NAVDAS) is used to assimilate the observations and provide the initial conditions for the COAMPS forecasts. Four data assimilation experiments are conducted as part of an observing system experiment (OSE) to investigate the impact of assimilating the extra radiosonde observations on COAMPS short-term forecasts (up to 48 h). The four experiments explore the impacts of assimilating the additional radiosonde observations in NAVDAS in cold-start or warm-start configuration. Based on the results from the four-month-long data assimilation tests, we find that assimilating the extra YOPP radiosonde observations improves the overall accuracy of the COAMPS short-term atmospheric forecasts over the Arctic for both cold-start and warm-start initializations. The warm-start configuration makes the most significant improvement to the COAMPS Arctic forecasts during the test period. The domain-averaged mean RMSE of the 48 h forecast from the warm-start assimilation is about 17% less than that from the cold-start initialization.
One Train May Hide Another: Katz, Stonewall, and the SecretSubtext of Criminal Procedure

One of the greatest practical achievements of Katz v. United States, now largely forgotten, was helping to restrict the once common practice of spying on men in toilet stalls to catch homosexuals. This may not have been accidental. The conception of privacy championed in Katz resonated strongly with pervasive concerns in the 1960s about homosexuality and its policing. The Justices, or at least some of them, may well have understood that Katz would make it harder for the police to keep toilet stalls under clandestine surveillance, and there is reason to believe they would have welcomed that result. In fact, homosexuality and its policing - especially male homosexuality and its policing - may be a suppressed subtext of modern criminal procedure more broadly. Anxieties about peepholes and undercover decoys in public lavatories, and about related investigative tactics targeted at homosexuality elsewhere, helped shape what the Court thought about the police and about the kinds of threats they posed. Traces of those anxieties may be visible in three pervasive features of the criminal procedure revolution: the preoccupation with protecting a particular kind of privacy, the view of police as psychologically antidemocratic, and the commitment to reining in police discretion with judge-made rules.
Experimental Evidence on Willingness to Pay for Red Meat Traceability in the United States, Canada, the United Kingdom, and Japan

We employed Vickrey auctions to generate willingness-to-pay (WTP) data for red meat traceability and related product characteristics with comparable experimental auctions in the United States, Canada, the U.K., and Japan. The results show that subjects are willing to pay a nontrivial premium for traceability, but the same subjects show even higher WTP for traceability-provided characteristics like additional meat safety and humane animal treatment guarantees. The implication is that producers might be able to implement traceable meat systems profitably by tailoring the verifiable characteristics of the product to consumer preferences.
PYRUVATE OXIDATION BY PASTEURELLA TULARENSIS STRAINS OF GRADED VIRULENCE

Weinstein, I. (U.S. Army Chemical Corps, Fort Detrick, Frederick, Md.), M. L. Guss, and R. A. Altenbern. Pyruvate oxidation by Pasteurella tularensis strains of graded virulence. J. Bacteriol. 83:1010–1016. 1962.—The rate of oxidation of sodium pyruvate by Pasteurella tularensis was shown to be correlated with the virulence of the strain studied. No qualitative differences in cofactor requirements for or products of pyruvate oxidation were found among strains of graded virulence. The rate of pyruvate oxidation was directly related to strain virulence, whereas the endogenous respiration rate was inversely correlated with virulence. For all tested strains possessing some degree of virulence, maximal rates of pyruvate oxidation were obtained with small concentrations of pyruvate (10 to 20 μmoles), above which the oxidation rate was depressed. Small concentrations of glutamate or other dicarboxylic acids effected nonadditive stimulation (sparking) of the pyruvate oxidation rate only at pyruvate concentrations above optimal (greater than 20 μmoles). The avirulent strain 38A was unique, being characterized by a low endogenous respiration rate, a maximal rate of pyruvate oxidation at all concentrations above 20 μmoles, and the absence of glutamate sparking. Studies of cell-free extracts indicated that the differences in pyruvate oxidation among the strains may be attributed in part to variation in the properties of enzymes of the tricarboxylic acid cycle.
Heparin promotes the binding of thrombin to fibrin polymer. Quantitative characterization of a thrombin-fibrin polymer-heparin ternary complex.

The binding of human alpha-thrombin (IIa) to fibrin polymer (FnIIp) was studied in the presence and absence of a high affinity 20,300 Mr heparin (H) at pH 7.4, I 0.15, and 23 degrees C. In the absence of heparin, thrombin interacts with a high affinity class of binding sites on fibrin polymer with a dissociation constant of 301 +/- 36 nM in a manner which is independent of the enzyme active site. Studies of thrombin binding as a function of heparin and fibrin polymer concentrations imply that a ternary thrombin-fibrin polymer-heparin complex (IIa.FnIIp.H) is formed. Assembly of the ternary complex occurs randomly through the interactions of all three possible intermediate binary complexes; IIa.H, IIa.FnIIp, and FnIIp.H. Using an independently determined value of 280 +/- 35 nM for the FnIIp.H dissociation constant, global fits of the binding data yield a dissociation constant of 15 +/- 6 nM for the IIa.H interaction and 47 +/- 9 nM for the IIa.H intermediate binary complex interaction with FnIIp. These studies indicate that heparin enhances the binding of thrombin to fibrin polymer 6.4-fold with an overall dissociation constant for ternary complex formation of 705 nM2. The effect of heparin molecular weight on ternary complex formation has also been investigated. Heparins of molecular weights 11,200-20,300 behave similarly with respect to their influence on ternary complex formation, whereas heparins of lower molecular weight are less effective in promoting thrombin binding to fibrin polymer. This effect of heparin is also independent of whether it has high or low affinity for antithrombin III. The demonstration of the formation of a ternary IIa.FnIIp.H complex complements kinetic evidence indicating the formation of an analogous ternary complex with fibrin II monomer (Hogg, P. J., and Jackson, C. M. (1989) Proc. Natl. Acad. Sci. U. S. A. 86, 3619-3623). The possible implications of these findings for the in vivo distribution and actions of thrombin and the clinical efficacy of heparin are also discussed.
A new forward-backward sweeping parabolized Navier-Stokes algorithm with application to magnetohydrodynamic flows

A new forward-backward sweeping parabolized Navier-Stokes algorithm has been developed to efficiently compute supersonic/hypersonic flowfields with embedded separated regions. The algorithm splits the streamwise flux vector using the Steger-Warming method and employs multiple forward/backward sweeps of the flowfield in order to duplicate the results that would be obtained with the complete Navier-Stokes equations. The forward/backward sweeping of the flowfield significantly reduces the number of iterations required over previous iterative parabolized Navier-Stokes algorithms. Once a separated flow region is computed, the algorithm returns to the usual forward-space-marching mode until the next separated flow region is encountered. The new algorithm has been applied to three separated flow test cases consisting of flow over a compression ramp and two flows over a hollow-cylinder-flare geometry. The present numerical results are in excellent agreement with complete Navier-Stokes computations and experimental data. In addition, the new algorithm has been extended to efficiently compute magnetohydrodynamic (MHD) flows in the low magnetic Reynolds number regime. In this regime, the electrical conductivity is low and the induced magnetic field is negligible compared to the applied magnetic field. This allows the MHD effects to be modeled by introducing source terms into the governing equations. Turbulence has been included by modifying the Baldwin-Lomax turbulence model to account for MHD effects. The new algorithm with MHD effects included has been used to compute both laminar and turbulent, supersonic, MHD flows over flat plates, and 3-D supersonic viscous flows in an experimental MHD channel. The new algorithms have been successfully incorporated into NASA's parabolized Navier-Stokes (UPS) code.
An efficiency study of transient wave generation in a thermoelastic layer with a pulsed laser

The efficiency of transient wave generation in a thermoelastic silicon layer excited by a pulsed laser is considered. First a principle-based transfer matrix formulation with relaxation effect, also referred to as the generalized dynamic theory of linear thermoelasticity, is used in obtaining transfer functions between the input heat field and the elements of the thermoelastic state vector. The second sound effect, through this relaxation time term, is included to eliminate the thermal wave travelling with infinite velocity as predicted by the diffusion heat transfer model. By employing the fast Fourier transform (FFT) algorithm, the transient response of a silicon thermoelastic layer under a thermal excitation (by a pulsed laser) is investigated to quantify the conversion efficiency from thermal to mechanical energy. The transient acceleration, stress, heat, temperature, and mechanical power flux responses are presented. The pulse duration of the laser excitation is submicrosecond level and, consequently, a large number of modes of motion are excited. Rigid body singularities are eliminated by considering the higher order time derivatives of the state variables. A layer made of bulk silicon under this laser excitation is considered and it is found that the amplitude ratio of the applied heat field to the propagating heat flux at the data points is in the order of 10°. The ratio of the applied power (heat flux) to the generated mechanical power flux is in the order of 10°. The resulting rigid body motion of the layer due to the laser excitation is excluded in calculating the mechanical power.
Complex regulation of the global regulatory gene csrA: CsrA-mediated translational repression, transcription from five promoters by Eσ70 and EσS, and indirect transcriptional activation by CsrA

Summary CsrA of Escherichia coli is an RNA-binding protein that globally regulates gene expression by repressing translation and/or altering the stability of target transcripts. Here we explored mechanisms that control csrA expression. Four CsrA binding sites were predicted upstream of the csrA initiation codon, one of which overlapped its Shine–Dalgarno sequence. Results from gel shift, footprint, toeprint and in vitro translation experiments indicate that CsrA binds to these four sites and represses its own translation by directly competing with 30S ribosomal subunit binding. Experiments were also performed to examine transcription of csrA. Primer extension, in vitro transcription and in vivo expression studies identified two σ70-dependent (P2 and P5) and two σS-dependent (P1 and P3) promoters that drive transcription of csrA. Additional primer extension studies identified a fifth csrA promoter (P4). Transcription from P3, which is indirectly activated by CsrA, is primarily responsible for increased csrA expression as cells transition from exponential to stationary-phase growth. Taken together, our results indicate that regulation of csrA expression occurs by a variety of mechanisms, including transcription from multiple promoters by two sigma factors, indirect activation of its own transcription, as well as direct repression of its own translation.
Mathematical optimization of photovoltaic converters for diode lasers

The mathematical optimization of vertical-junction photovoltaic converters for use with diode laser arrays supplying powers of up to 1 MW is discussed. Photovoltaic parameters were optimized using a mathematical model. The optimized converters have 500 single junctions connected in series. The efficiency varies from 41% for a 0.73 mu m diode laser to 46% for a 0.83 mu m diode laser. The optimum width of the single-junction converter is small, 3.0 mu m, in order for the p-n junction to be within a diffusion length of the light-generated carriers. Another critical parameter is the series resistance; the optimum value of 1*10/sup -3/ Omega should be achievable. Another critical parameter is the donor carrier concentration, for which an optimum value of 5*10/sup 15/ carriers/cm/sup 3/ has been chosen. >
Regulation of the Fatty Acid Synthase Promoter by Insulin

Expression of critical enzymes in fatty acid and fat biosynthesis is tightly controlled by nutritional and hormonal stimuli. The expression of fatty acid synthase, which catalyzes all reactions for synthesis of palmitate from acetyl-CoA and malonyl-CoA, and of mitochondrial glycerol-3-phosphate acyltransferase, which catalyzes the first acylation step in glycerophospholipid synthesis, is decreased to an undetectable level during fasting. Food intake, especially a high carbohydrate, fat-free diet after fasting, causes a dramatic increase in the transcription of these genes. Insulin secretion is increased during feeding and has a positive effect on expression. By using adipocytes in culture and transgenic mice that express the reporter gene driven by the fatty acid synthase promoter, the cis-acting sequence that mediates insulin regulation of the fatty acid synthase promoter was defined. Upstream stimulatory factors (USF) that bind to the -65 E-box are required for insulin-mediated transcriptional activation of the fatty acid symthase gene. Sterol regulatory element binding protein (SREBP)-1 may be also involved in induction of these genes during feeding. Using specific inhibitors and expressing various signaling molecules, we found that insulin regulation of the fatty acid synthase promoter is mediated by the phosphatidylinositol (PI)3-kinase signaling pathway and that protein kinase B/akt is a downstream effector.
A Further Look at the Dramatic Parallels in García Lorca and Tennessee Williams: The Poetic Qualities and Symbolism in Yerma and The Purification

Este trabajo corresponde a una secuencia de un estudio anterior sobre las similitudes entre Federico Garcia Lorca y Tennessee Williams. Este analisis presenta las analogias entre las obras Yerma de Lorca y Purification de William.
Manifesto on Dyslexia

Publisher Summary This chapter discusses the testing of specific performance in dyslexia. It describes a simple perceptual test method. In this test, pairs of letters are projected tachistoscopically on a screen. One letter of the pair is always presented at the centre of gaze and the other letter in the peripheral field along the horizontal axis. In successive presentations, the peripheral letters are presented at different eccentricities (angular distances to either side from the centre of gaze). Each test consists of 200 such presentations. The response to each pair is recorded, and the plot of the average of correct peripheral letter identification against eccentricity is called the form-resolving field (FRF). As a diagnostic measure, the FRF is an easier test to perform than analysis of lateral masking within short strings of letters at different eccentricities. The chapter also discusses the results of some studies that show that dyslexics and ordinary readers are systematically different under a specific visual perception FRF test and the difference is in the hemifield corresponding to the direction of reading.
Steve the Steampunk Robot

Science Fiction Prototyping column editor Brian David Johnson sits down with eight-year-old Cole to imagine a robot when he least expects it--on vacation. The Web extra at http://youtu.be/hltHbW8Q22s is an audio interveiw in which author Brian David Johnson sits down with eight-year-old Cole to imagine a robot when he least expects it--on vacation.
Investigating morphological awareness and the processing of transparent and opaque words in adults with low literacy skills and in skilled readers

For adults with low literacy skills, the role of phonology in reading has been fairly well researched, but less is known about the role of morphology in reading. We investigated the contribution of morphological awareness to word reading and reading comprehension and found that for adults with low literacy skills and skilled readers, morphological awareness explained unique variance in word reading and reading comprehension. In addition, we investigated the effects of orthographic and phonological opacity in morphological processing. Results indicated that adults with low literacy skills were more impaired than skilled readers on items containing phonological changes but were spared on items involving orthographic changes. These results are consistent with previous findings of adults with low literacy skills reliance on orthographic codes. Educational implications are discussed.
Nucleotide sequence of Xenopus borealis oocyte 5S DNA: comparison of sequences that flank several related eucaryotic genes.

Abstract Genomic Xenopus borealis oocyte-specific 5S DNA (Xbo) contains clusters of 5S rRNA genes. The number of genes varies among clusters, and the distance between genes within a cluster is about 80 nucleotides. The spacer DNA between gene clusters is AT-rich and heterogeneous in length due in part to variable numbers of a tandemly repeated 21 nucleotide sequence. A cloned fragment of Xbo 5S DNA (Xbo1) containing three 5S rRNA genes has been sequenced. The sequences of Xbo1 genes 1 and 2 are very similar to the dominant 5S RNA sequence, whereas 15 of the 120 residues in the third gene are different. The sequence of gene 3 is as different from the dominant gene sequence as the X. laevis pseudogene is from the 5S RNA gene. Sequence analysis of genomic DNA shows that gene 3 is an abundant component of the multigene family. All three genes are transcribed when added to an extract of X. laevis oocyte nuclei, and a fragment of Xbo1 lacking the AT-rich spacer DNA and the 5′ end of the first gene supports transcription of genes 2 and 3 in this in vitro system. Thus the 80 nucleotides preceding each 5S gene are sufficient for promoter function. Nucleic acid sequences preceding several eucaryotic genes that are transcribed by RNA polymerase III were analyzed and the following common features were found: a purine-rich region; at least one direct repeat; the absence of dyad symmetry; transcription beginning with a purine; a pyrimidine residue immediately preceding the first nucleotide of the gene; and the oligonucleotides AAAAG, AGAAG and GAC, located approximately 15, 25 and 35 nucleotides, respectively, before the start of transcription. The 10 base pair (bp) spacing between the homologous oligonucleotides is that expected for a recognition signal on one face of a DNA double helix. The extensive sequence differences between most of the spacers that precedes these genes make the three conserved oligonucleotides more striking. Parts of the 5′ flanking regions of the three Xbo1 genes (−12 to −40), which include the conserved oligonucleotides, are identical. In contrast, 7 of the first 11 nucleotides that precede the third 5S RNA gene in Xbo1 differ from those that precede the first gene. The sequences following the X. borealis oocyte and somatic 5S genes are identical in 12 of the first 14 residues and contain two or more T clusters, as does the corresponding region of X. laevis oocyte 5S DNA. The 3′ sequences of the Xenopus 5S rRNA genes and several other eucaryotic genes contain features in common with procaryotic transcription termination sites. The 3′ end of the gene is GC-rich and contains a dyad symmetry. Termination occurs in an AT-rich region containing one or more T clusters on the noncoding strand.
Tension Induces Changes in Lipid Lateral Diffusion in Model Fluid-Phase Membranes

Shear stress due to blood flow on endothelial cells elicits numerous responses including G-protein coupled receptor activation and integrin-mediated signaling. Shear-induced change in membrane fluidity has been suggested to be one of the earliest mechanosensing mechanism involved in these processes [1, 2]. Alternatively, it has been suggested that shear forces are transduced through glycocalyx directly to transmembrane proteins and cytoskeleton [3], with very little shear force sensed by the membrane. It is not yet clear whether physiological tensions can alter membrane fluidity significantly.Copyright © 2009 by ASME
Central Nervous System Agents in the Treatment of Erectile Dysfunction

Abstract In the last two decades, a better understanding of the mechanisms governing erectile function and the pathophysiologies underlying erectile dysfunction (ED) have led re-searchers to investigate novel treatment concepts. Selective type-5 phosphodiesterase inhibitors are recommended as first-line therapy because of their high efficacy, but 30% to 40% of patients who have ED do not respond adequately to these agents and require alternative methods. The central nervous system plays a fundamental role in sexual behavior. Animal models have advanced our understanding of the neuroanatomic and neuropharmacologic basis of centrally induced penile erections. Clinical research with apomorphine has demonstrated efficacy in men who have a range of ED. Recent interest has focused on other centrally acting agents for ED treatment, including the melanocortin receptor agonists.
Mechanisms of coexistence between native bull trout (Salvelinus confluentus) and non-native lake trout (Salvelinus namaycush): inferences from pattern-oriented modeling

Determining the ecological mechanisms that control population abundances is an important issue for the conservation of endangered and threatened species. We examined whether a threatened bull trout...
Search for an adenine photoproduct in DNA.

Abstract Poly(d[14C]A), p(dA)2, and [14C]adenosine-labeled DNA were irradiated at 254 nm with fluences up to 50 J/m2, and then following formic acid hydrolysis at 170 degrees C WERE SUBJECTED TO PAPER CHROMAtography using a butanol:water:acetic acid (80:30:12) solvent system. For poly(dA), up to 25% of the radioactivity appeared as fluorescent material located in the Rf 0.21-0.29 region. The hydrolysate of the purified photoproduct, p(dA)2, isolated from irradiated p(dA)2 by DEAE chromatography also had an Rf of 0.29 as well as an absorbance maximum at 310 nm. In all cases studied, however, the photoproduct yield in the Rf 0.29 region for native DNA was less than 2%. Denaturation of the DNA appeared to enhance the yield slightly, although no pronounced peak in this region of the chromatogram was discerned. Mechanistic studies indicate that the yield of the adenine photoproduct in poly(dA) is favored by base stacking, has a singlet excimer as a precursor, and is quenched by hydrogen bonding to a pyrimidine. It is concluded that the yield of the adenine photoproduct in both native and denatured DNA is considerably less than in poly (dA) and in all probability does not represent a biologically significant product.
The cost of ventilation in birds measured via unidirectional artificial ventilation

Abstract The highly derived mechanism birds use to ventilate their lungs relies on dorsoventral excursions of their heavily muscled sternum and abdominal viscera. Our expectation of the level of mechanical work involved in this mechanism led us to hypothesize that the metabolic cost of breathing is higher in birds than in other tetrapods. To test this theory, we used unidirectional artificial ventilation (UDV) to stop normal ventilatory movements in guinea fowl ( Numida meleagris L.) at rest and during treadmill locomotion at three speeds. Oxygen consumption was measured during normal breathing and UDV, and the difference was used to approximate the cost of ventilation. Contrary to our prediction, metabolism increased when ventilatory movements ceased during UDV at rest. Although we do not understand why this occurred we suspect that UDV induced a homeostatic mechanism to counteract the loss of carbon dioxide. Nevertheless, across all running speeds, metabolism decreased significantly with UDV, indicating a minimum cost of ventilation during running of 1.43 ± 0.62% of total running metabolism or 0.48 ± 0.21 mL O 2 (L ventilated) − 1 . These results suggest that the metabolic cost of ventilation is low in birds and that it is within the range of costs reported previously for other amniotes.
Occurrence and load of selected herbicides and metabolites in the lower Mississippi River.

Analyses of water samples collected from the Mississippi River at Baton Rouge, Louisiana, during 1991–1997 indicate that hundreds of metric tons of herbicides and herbicide metabolites are being discharged annually to the Gulf of Mexico. Atrazine, metolachlor, and the ethane-sulfonic acid metabolite of alachlor (alachlor ESA) were the most frequently detected herbicides and, in general, were present in the largest concentrations. Almost 80% of the annual herbicide load to the Gulf of Mexico occurred during the growing season from May to August. The concentrations and loads of alachlor in the Mississippi River decreased dramatically after 1993 in response to decreased use in the basin. In contrast, the concentrations and loads of acetochlor increased after 1994, reflecting its role as a replacement for alachlor. The peak annual herbicide load occurred in 1993, when approximately 640 metric tons (t) of atrazine, 320 t of cyanazine, 215 t of metolachlor, 53 t of simazine, and 50 t of alachlor were discharged to the Gulf of Mexico. The annual loads of atrazine and cyanazine were generally 1–2% of the amount annually applied in the Mississippi River drainage basin; the annual loads of acetochlor, alachlor, and metolachlor were generally less than 1%. Despite a reduction in atrazine use, historical data do not indicate a long-term downward trend in the atrazine load to the Gulf of Mexico. Although a relation (r2=0.62) exists between the atrazine load and stream discharge during May to August, variations in herbicide use and rainfall patterns within subbasins can have a large effect on herbicide loads in the Mississippi River Basin and probably explain a large part of the annual variation in atrazine load to the Gulf of Mexico.
Heterogeneous catalytic reaction of elemental mercury vapor over cupric chloride for mercury emissions control

Abstract In this study, the reaction mechanism of Hg(0) vapor oxidation over cupric chloride (CuCl 2 ) was investigated using 10% (wt) CuCl 2 /α-Al 2 O 3 for mercury emissions control from coal-fired power plants. The CuCl 2 /α-Al 2 O 3 sample showed >90% Hg(0) oxidation with excellent resistance to SO 2 at 140 °C in a simulated flue gas containing 10 ppmv HCl, 2000 ppmv SO 2 , and 6% O 2 gases balanced with N 2 gas. In the absence of HCl and O 2 gases, Hg(0) vapor was found to be oxidized by consuming atomic Cl of CuCl 2 and reducing it to CuCl, following a Mars–Maessen mechanism. The reduced CuCl could be re-chlorinated back to CuCl 2 by replenishing empty Cl atoms under 10 ppmv HCl and 6% O 2 gases readily present in coal combustion flue gases even under 2000 ppmv SO 2 concentration for continuous Hg(0) oxidation. Cl 2 gas generation was not observed over CuCl 2 at 140 °C, indicating a heterogeneous catalytic reaction. CuCl 2 shows potential that can be realized in a honeycomb or plate catalyst bed.
Impairment of male copulatory behavior in rhesus monkeys following acute administration of cocaine

Abstract Although numerous studies in nonhuman primates have demosntrated an influence of cocaine on behavior, no studies have yet examined whether cocaine affects sexual behavior in nonhuman primates. The objective of the present study was to examine the acute effects of cocaine on male copulatory behavior of rhesus monkeys. Administration of cocaine produced dose-dependent effects on male copulatory behavior, with monkeys taking significantly longer to initiate copulation (mount latency) and achieve an ejaculation (ejaculation latency) after receiving 200–800 μg/kg cocaine. Male copulatory behavior was not affected by cocaine at doses below 200 μg/kg. These results indicate that cocaine can acutely impair sexual behavior performance of male rhesus monkeys. Further study is needed to determine the possible long-term consequences of chronic cocaine administration on male sexual behavior.
CLASPs link focal adhesion-associated microtubule capture to localized exocytosis and adhesion site turnover

Turnover of integrin-based focal adhesions (FAs) with the extracellular matrix (ECM) is essential for coordinated cell movement. In collectively migrating human keratinocytes, FAs assemble near the leading edge, grow and mature as a result of contractile forces and disassemble underneath the advancing cell body. We report that clustering of microtubule-associated CLASP1 and CLASP2 proteins around FAs temporally correlates with FA turnover. CLASPs and LL5β (also known as PHLDB2), which recruits CLASPs to FAs, facilitate FA disassembly. CLASPs are further required for FA-associated ECM degradation, and matrix metalloprotease inhibition slows FA disassembly similarly to CLASP or PHLDB2 (LL5β) depletion. Finally, CLASP-mediated microtubule tethering at FAs establishes an FA-directed transport pathway for delivery, docking and localized fusion of exocytic vesicles near FAs. We propose that CLASPs couple microtubule organization, vesicle transport and cell interactions with the ECM, establishing a local secretion pathway that facilitates FA turnover by severing cell-matrix connections.
Assessment of long scale plume transport to the US East coast using coordinated CREST lidar network and synergistic AERONET and satellite measurements

The vertical stratification and optical characteristics of aloft aerosol plumes are critical to evaluate their influences on climate radiation and air quality. In this study, we demonstrate the synergistic measurements of aloft aerosol plumes by a ground-based NOAA-CREST lidar network (CLN) along the US East Coast, the AERONET-sun/sky radiometer network at lidar sites, and satellite observations. During the plume intrusion period on March 6, 2012, the CLN and AERONET measurements were consistent in illustrating the onset of dust aerosol plumes. We observed two-layers of aerosol located at 1.0 ~ 8.0 km altitude. The column-average volume size distributions show increasing concentration of both fine- and coarse-modes aerosols, but are dominated by the coarse-mode. Direct lidar inversions illustrate that the aerosol plume layers contributed up to 70% of the total AOD. NOAA-HYSPLIT back-trajectories and CALIPSO observations indicate the trans-Pacific transport of Asian-dust at 3 - 8 km altitude to the US East Coast. Meanwhile, the NOAA-HMS fire and smoke products illustrate the transport and possible mixture of dust with fine-mode smoke particles from the middle and southwestern US. The small Angstrom exponents of MODIS/Aqua in the US East Coast imply the dominance of coarse-mode particles. Accordingly, the upper layer of coarse mode aerosols is most likely transported from the East Asia, while the lower layer at 1-3 km altitude probably consists of continental dust particles from the western US mixed with fine-mode smoke particles. In addition, the transport and vertical structure of aerosol are investigated with the NAAPS global aerosol transport model.
A Sensory Profile of Turnip Greens as Affected by Variety and Maturity

: Turnip greens, a Brassica, are characterized by a sulfurous aroma, pungent flavor, and a bitter taste due to isothiocyanates, degradation products of glucosinolates. This study examined the sensory characteristics and preference of turnip greens as affected by variety and maturity. A descriptive analysis panel characterized 16 aromas, flavors, and tastes. The intensity of mustard oil/mustard green aroma and flavor and bitterness was significantly affected (P < 0.05) by variety. Mustard oil/mustard green aroma and flavor, bitterness, and bitter aftertaste increased significantly (P < 0.05) with maturity. Seven Top was preferred significantly (P < 0.05) less than the remaining varieties and as the greens matured, preference decreased.
Stabilities of Monobridged Binuclear Cobalt Dioxygen Complexes: A Linear Free Energy Relationship

Abstract Equilibrium data for oxygenation of a number of cobalt(II) complexes of pentadentate ligands that form 5-membered chelate rings indicate that the logarithms of the stability constants of the oxygen adduct do not correlate with the stability constants of the cobalt (II)-ligand complexes, but correlate linearly with the sums of the pK ' s of the ligand donor groups coordinated to the cobalt.
Smaller and Faster: The 20-Residue Trp-Cage Protein Folds in 4 μs

We have used laser temperature jump spectroscopy to measure the folding speed of the 20-residue Trp-cage, the smallest polypeptide known to exhibit truly cooperative folding behavior. The observed folding time (4 μs at room temperature) makes this not only the smallest foldable protein, but also the fastest, with a folding speed that exceeds contact-order predictions and approaches anticipated diffusional “speed limits” for protein folding.
Bile acids LXIX. Selective K-Selectride reduction of 3,7-diketo steroids

Abstract The K-Selectride reduction at low temperature (-45°C) of 7-oxo-5α-holestan-3β-yl acetate and methyl 7-oxo-3α-hydroxy-5(β-cholanoate resulted in almost quantitative yield of the 7α-alcohol in the 5α-compound but only moderate yield of the 5β-analog. The simultaneous reduction of two carbonyl groups in the 3 and 7 positions afforded good to excellent yields of the diaxial diol in planar steroids (methyl 3,7-dioxo-5α-cholanoate, 3,7-dioxo-5α-cholestane and methyl 3,7-dioxo-5α-cholestan-27-oate) and only 14% of 3α,7α-(OH) 2 from methyl 3,7-dioxo-5β-cholanoate.
Rapid, high-yield purification of cell surface membrane using colloidal magnetite coated with polyvinylamine: sedimentation versus magnetic isolation.

Abstract A new technique for the magnetic isolation of external plasma membrane from Dictyostelium discoideum is described and compared to a previously published procedure employing sedimentation of silica-coated plasma membrane. The magnetic isolation technique involves coating intact cells with a polyvinylamine-magnetite colloid and overcoating with polyacrylate to form a dense pellicle. The magnetite pellicle totally coated the cells and was not internalized. Coated cells were lysed and membrane fragments retrieved from the cell homogenate using a diverging field electromagnet. The membrane obtained in such a manner was analyzed for marker enzyme activity and cell surface label. The plasma membrane was obtained in high yield (42%) with an average purification of 8-fold. The polyvinylamine-magnetite pellicle shielded the external plasma membrane face to proteolysis by papain and pronase. It also acted as a barrier to α-methylmannoside in concanavalin A-carbohydrate competition studies.
Effects of buffer systems on the interaction of the potent nephrotogenic aminonucleoside of pur014ycin with rat kidney cortex microsomes

Abstract Study of the effects of pH on the interaction of the nephrotogenic aminonucleoside of puromycin with rat kidney cortex microsomes clearly indicates that binding of aminonucleoside to the microsomal fraction is sharply reduced when equilibrium dialysis experiments are conducted in the presence of the Good series of buffers, and in the presence of glycylglycine or phosphate buffers. Marked similarity in binding values, obtained in the presence of the Good series of buffers over the pH range 6.21 to 8.71, suggests a common mechanism of interference of these buffers with the binding of aminonucleoside to the microsomal fraction, and a buffer effect independent of pH. In experiments conducted with any one buffer compound, adjusted to different pH values, however, a pH effect was discernible.
The direct thionation and aminoalkylation of pyridine 1-oxides and related reactions†

The reaction of lithiopyridine 1-oxides with oxygen gives poor yields of 1-hydroxy-2-pyridones. The reaction with sulfur, however, is a convenient route to the 1-hydroxy-2-pyridinethiones which have useful antibacterial and antifungal activity. Reaction with ethylene oxide gives mainly polymeric products, but addition to Shiff's bases promises to be a convenient mode of mono-, and particularly di-α-aminoalkylation of pyridine 1-oxides.
A tubular film extrusion of poly(vinylidene fluoride): structure/process/property behavior as a function of molecular weight

Abstract Five different poly(vinylidene fluoride) (PVDF) resins spanning the molecular weights from 85,000–250,000 g/mol with nearly comparable polydispersities of ca. 2.0 were investigated with respect to their strain induced crystalline morphologies as produced by a tubular uniaxial film extrusion process. By holding the process time window constant through the use of fixed melt temperature, line speed, quench height and film thickness, it was noted that as molecular weight increased, the uniaxial films produced systematically change from nearly a spherulitic structure to that of an extremely high concentration of fibril nuclei with minimal growth of folded chain lamella developing perpendicular to the fibrils. The systematic variation in the morphology was directly coupled through consideration of the melt process time window in conjunction with the characteristic relaxation time of a given resin at a given temperature. The latter was determined through use of a Carreau–Yasuda analysis of the melt rheological behavior of each resin and this relaxation time, when correlated to the process time, produced a relative Deborah number. It was distinctly shown that when the Deborah number was considerably less than unity, little crystal orientation was observed in the morphological texture whereas in the range of unity, a distinct rise in crystalline orientation occurred leading to fibril nucleation with lamella side growth in the form of the well known row structure morphology. Exceeding a Deborah number of unity led to nearly full crystalline orientation saturation and to a very high concentration of fibril nucleai with relatively few orthogonal lamella observable. The morphological textures were investigated using AFM, WAXS, SALS, SAXS and birefringence. Use of thermal analysis to determine some of the polymorphic character of the PVDF crystal form was also undertaken.