cssi/SciSciGPT-SciSciNet huggingface dataset:
Human plasma protein binding of the angiotensin II receptor antagonist losartan potassium (DuP 753/MK 954) and its pharmacologically active metabolite EXP3174.

The in vitro protein binding characteristics of the prototypical angiotensin II receptor antagonist losartan potassium (DuP 753/MK 954) and its pharmacologically active metabolite EXP3174 were determined by ultrafiltration with plasma from naive donors, volunteers dosed with losartan, and purified human plasma proteins. The binding of losartan was high, with a percent unbound (free) of 1.4 +/- 0.2% to 1.2 +/- 0.1% at concentrations ranging from 0.5 to 5.0 micrograms/mL; that is, approximately 98.6 to 98.8% bound. EXP3174 was more highly bound than losartan (P < .05) with 0.2 +/- 0.0% free at concentrations ranging from 0.1 to 10.0 micrograms/mL; or, greater than 99.7% bound. The binding in the plasma from volunteers given oral losartan was similar to that determined with plasma from naive donors, with 1.5 +/- 0.3 versus 1.4 +/- 0.1% free for losartan, and 0.5 +/- 0.1 versus 0.4 +/- 0.0% for EXP3174, respectively. This extensive plasma binding of both acidic compounds occurs primarily to albumin, with negligible binding to the alpha 1-acid glycoprotein. Although highly bound, neither losartan nor EXP3174 were displaced in vitro by pharmacologically relevant concentrations of non-steroidal antiinflammatory drugs (NSAIDs), warfarin, or diazepam; however, suprapharmacologic concentrations of the NSAIDs increased the free fraction of both compounds. These data show that the angiotensin II receptor antagonists losartan and EXP3174 are highly bound to plasma albumin in humans, although clinically significant drug interactions due to displacement from binding sites are unlikely.(ABSTRACT TRUNCATED AT 250 WORDS)
New thermo-oxidative protective coating for carbon/carbon composites in mid-temperature range using a combination of nano-filler and macro-filler with polybenzoxazine as a carbon-forming matrix

A novel main-chain type, oligomeric benzoxazine has been synthesized as a highly thermo-oxidative matrix material. The structure of the monomer is confirmed by 1H nuclear magnetic resonance spectroscopy and size exclusion chromatography. Octasilane polyhedral oligomeric silsesquioxane (OctaSilane POSS) and glass sphere are incorporated to form an effective oxidation-protective coating for the carbon/carbon composites. The composition has been optimized by varying benzoxazine and OctaSilane POSS ratio with the aid of thermogravimetric analyses. The even distribution of the three components has been confirmed by laser Raman image, and the effectiveness of the coating has been investigated using isothermal weight loss measurement at 700°C in air for 1300 h. POLYM. COMPOS., © 2011 Society of Plastics Engineers.
Monoamine Oxidase A Genotype, Childhood Trauma, and Subclinical Atherosclerosis: A Twin Study

Objective A functional promoter polymorphism in the MAOA gene has been implicated in neuropsychiatric disorders and also moderates the association between early life stress and mental disorders, which often co-occur with cardiovascular disease. No study has examined the relationship between MAOA genotype, childhood trauma and subclinical atherosclerosis. The objective of this investigation was to examine whether childhood trauma moderates the association between MAOA genotype and subclinical atherosclerosis.
Extracting rate coefficients from single-molecule photon trajectories and FRET efficiency histograms for a fast-folding protein.

Recently developed statistical methods by Gopich and Szabo were used to extract folding and unfolding rate coefficients from single-molecule Forster resonance energy transfer (FRET) data for proteins with kinetics too fast to measure waiting time distributions. Two types of experiments and two different analyses were performed. In one experiment bursts of photons were collected from donor and acceptor fluorophores attached to a 73-residue protein, α(3)D, freely diffusing through the illuminated volume of a confocal microscope system. In the second, the protein was immobilized by linkage to a surface, and photons were collected until one of the fluorophores bleached. Folding and unfolding rate coefficients and mean FRET efficiencies for the folded and unfolded subpopulations were obtained from a photon by photon analysis of the trajectories using a maximum likelihood method. The ability of the method to describe the data in terms of a two-state model was checked by recoloring the photon trajectories with the extracted parameters and comparing the calculated FRET efficiency histograms with the measured histograms. The sum of the rate coefficients for the two-state model agreed to within 30% with the relaxation rate obtained from the decay of the donor-acceptor cross-correlation function, confirming the high accuracy of the method. Interestingly, apparently reliable rate coefficients could be extracted using the maximum likelihood method, even at low (<10%) population of the minor component where the cross-correlation function was too noisy to obtain any useful information. The rate coefficients and mean FRET efficiencies were also obtained in an approximate procedure by simply fitting the FRET efficiency histograms, calculated by binning the donor and acceptor photons, with a sum of three-Gaussian functions. The kinetics are exposed in these histograms by the growth of a FRET efficiency peak at values intermediate between the folded and unfolded peaks as the bin size increases, a phenomenon with similarities to NMR exchange broadening. When comparable populations of folded and unfolded molecules are present, this method yields rate coefficients in very good agreement with those obtained with the maximum likelihood method. As a first step toward characterizing transition paths, the Viterbi algorithm was used to locate the most probable transition points in the photon trajectories.
Ulongapeptin, a cytotoxic cyclic depsipeptide from a Palauan marine cyanobacterium Lyngbya sp.

Ulongapeptin (1), a cyclic depsipeptide, was isolated from a Palauan marine cyanobacterium Lyngbya sp. The gross structure was elucidated through one-dimensional TOCSY experiments and other spectroscopic techniques. The absolute and relative stereochemistry of the β-amino acid, 3-amino-2-methyl-7-octynoic acid (AMO), in 1 was determined by synthesis of the saturated α-alkyl-β-amino acid and Marfey's analysis of the acid hydrolysate of tetrahydro-1. Ulongapeptin (1) was cytotoxic against KB cells at an IC50 value of 0.63 μM.
The Natural History of Observed Enhancing Renal Masses: Meta-Analysis and Review of the World Literature

Purpose: Standard therapy for an enhancing renal mass is surgical. However, operative treatment may not be plausible in all clinical circumstances. Data on the natural history of untreated enhancing renal lesions is limited but could serve as a decision making resource for patients and physicians. We examined available data on the natural history of observed solid renal masses.Materials and Methods: A Medline review of the literature was performed from 1966 to the present regarding untreated, observed, localized solid renal masses. To these data we added our institutional experience with a total of 61 lesions observed in 49 patients for a minimum of 1 year. Variables examined were initial lesion size at presentation, growth rate, duration of followup, pathological findings and progression to metastatic disease. Overall weighted mean estimates were calculated for lesion size at presentation, growth rate and followup based upon combining single institutional series with complete information.Results: We iden...
Is novel wheel inhibition of per1 and per2 expression linked to phase shift occurrence

We studied whether access to a novel running wheel in vivo could reset the suprachiasmatic nuclei (SCN) in vitro. Golden hamsters were transferred to dim red light at Zeitgeber time (ZT) 4, given their first exposure to a running wheel for 3 h, and killed at either ZT7 or ZT9. Using a brain slice preparation, the SCN firing rate rhythm in vitro was advanced relative to controls only in the slices prepared at ZT9 (phase shift: 2.36+/-0.06 h, n=4) but not ZT7 (-0.26+/-0.16 h, n=4). Transitions to dim red light or brain slice preparation at ZT7 or ZT9 alone do not shift the rhythm. Hamsters with wheels had significantly lower levels of SCN per1 mRNA compared with controls at ZT7, and lower per2 mRNA when examined at ZT9. We conclude that 3 h of novel wheel access appears to require some extended time in vivo in order for the SCN to be reset, even beyond the time when per1 mRNA levels have been altered.
Complete endoscopic mucosal resection is effective and durable treatment for Barrett's-associated neoplasia.

Background & Aims Barrett's esophagus (BE) with high-grade dysplasia (HGD) or intramucosal carcinoma (IMC) is treated by complete eradication of areas of BE by endoscopic mucosal resection (EMR). By using this approach, histologic analysis also can be performed. We investigated the effectiveness, safety, and durability of this approach, as well as its use in diagnosis after a single referral. Methods We collected data from 107 patients who were referred to the Center for Endoscopic Research and Therapeutics at the University of Chicago for BE (mean length, 3.6 cm) with suspected HGD or IMC, from August 2003 through December 2012. All patients underwent EMR and were followed up through January 2014 (mean follow-up time, 40.6 mo). The primary outcome was treatment efficacy (complete eradication of BE and associated neoplasia); secondary outcomes included safety, durability, and accuracy of diagnosis. Results BE was eradicated completely by EMR in 80.4% (86 of 107) of patients based on intention-to-treat analysis, and in 98.8% (79 of 80) of patients based on per-protocol analysis. The diagnosis was changed for 25% of patients after EMR, including 4 cases that initially were diagnosed as HGD by biopsy analysis and subsequently were found to have evidence of submucosal invasion when EMR specimens were assessed. Strictures and symptomatic dysphagia developed in 41.1% and 37.3% of patients, respectively, with an average of 2.3 dilations required. Perforations occurred in 2 patients after EMR and in 1 patient after dilation. HGD and IMC recurred in 1 patient each; both were treated successfully with EMR. Based on pathology analysis of the most recently collected specimens, 71.6% of patients (53 of 74) were in complete remission from intestinal metaplasia and 100% were in complete remission from HGD (74 of 74) or cancer (74 of 74). Conclusions For patients with BE with HGD or neoplasia, complete EMR is an effective and durable treatment and is a relatively safe technique. Specimens collected by EMR also can be analyzed histologically to aid in diagnosis. The common complication of EMR is esophageal stricture, which can be addressed with endoscopic dilation.
The Stability of Self-Reported Marijuana Use across Eight Years of the National Longitudinal Survey of Youth

This study examined teen marijuana report stability over 8 years. The stability of self-reports refers to the consistency of self-reported use across several years. This study used fives waves of data across 8 years from the National Longitudinal Survey of Youth. Analyses were conducted to examine the internal or within-wave consistency as well as external or across-waves consistency for self-reported marijuana use. Further tests were conducted to identify if there were any differences for age, ethnicity, and sex for report consistency. Report stability was higher for lifetime use reports than the age of onset reports. Wave-by-wave differences revealed stability remained at acceptable levels in nearly all comparisons at agreement being about 75%. Overall, report agreement was higher for females, older adolescents, and non-Hispanic/non-black youths in bivariate analyses. However, only older chronological age remained consistently significantly associated with better report stability in multiple logistic re...
Asthma Clinical Research Network: lessons learned.

The Asthma Clinical Research Network was created by the National Heart, Lung, and Blood Institute to improve public health by rapidly evaluating novel and existing therapeutic approaches to asthma. The multicenter clinical research network has greatly contributed to the healthcare community's understanding of asthma by conducting clinical trials independent of the pharmaceutical industry. The following manuscript reviews the experimental design and major findings of noteworthy studies performed in this network. All of the network's publications were reviewed, and 19 were selected for summary. As shown in these publications, the research performed by the Asthma Clinical Research Network has produced significant data with important implications that should impact the way the healthcare community treats asthma at the present time. Mt Sinai J Med 78:671–682, 2011.© 2011 Mount Sinai School of Medicine
Periodic and chaotic behaviour of a simple R&D model☆

Abstract The present paper deals with the dynamics of a simple descriptive non-linear R&D model. Special emphasis is put on the decision-making behaviour of real agents. Although our two-dimensional model is quite simple it produces periodic and chaotic behaviour. Despite we mainly concentrate on using numerical methods, we also present theoretical arguments for the occurrence of chaotic behaviour. We show that our time-discrete model can be reduced to a one-dimensional model by using a technique which is similar to the Poincare section of ordinary differential equations. This one-dimensional model has the same dynamic properties. Since a majority of the theorems and results are in the context of dynamics in one dimension, we gain further insights by applying some interesting propositions.
Semiempirical and ab initio transition state calculations for the transformation of N-acetyltetrazoles into corresponding 1,3,4-oxadiazoles

Abstract The transformation of 2-acetyl-5-substituted-tetrazoles into the corresponding 1,3,4-oxadiazoles was studied with the mopac semiempirical and gaussian ab initio methods. Two mechanisms, one with two transition states and the other with three, were elucidated by mopac . The first mechanism supported by PM3 and MNDO has a two-step, almost concerted, mechanism for the elimination of a nitrogen molecule from the tetrazole ring and formation of the oxadiazole product from an open-chain intermediate through carbon C5 and acetyl oxygen bond formation. The second mechanism supported by AM1 and MINDO/3 breaks the elimination of the nitrogen molecule into two steps: first breaking the N4-C5 and then the N2-N3 bonds. Even when the AM1 and MINDO/3 transition state structures were optimized by PM3 and MNDO, the obtained transition states present only one bond breaking. The HF/STO-3G and HF/3-21G ab initio methods agree with the first mechanism where two bonds are breaking almost simultaneously. Despite the disagreement in the mechanism of the nitrogen elimination, the transition state that presents the product formation from open-chain intermediates is quite similar for all methods studied. The semiempirical calculation of this transition state is possible only if it is assumed that it has biradical character. The activation energies calculated by PM3 seem to be insensitive to the nature of the substituents.
Nanoelectromechanical systems: Tuning in to a graphene oscillator

Self-sustaining electromechanical oscillators can be built from graphene membranes that vibrate at radiofrequencies and can be tuned by a gate voltage.
Logarithmic Temperature Dependence of the Sound Speed in Amorphous Silica at Low Temperatures

The tunneling model has enjoyed considerable success in describing the low temperature properties of glasses. However, departures from the tunneling model have been noted in experiments at very low temperatures (below 100 mK). We have measured the change in the sound speed ΔV/V 0 between 1 and 40 mK in an amorphous silica double paddle oscillator oscillating at 14 kHz. Most importantly, the sound speed displayed the logarithmic temperature dependence predicted by the tunneling model to a lower temperature than in previous experiments on amorphous silica. Below 3 mK the sound speed departed from the logarithmic temperature dependence and began to level off. The leveling off can be explained by either an intrinsic effect or thermal decoupling of the sample from the thermometer. By heating the oscillator with a gamma source to determine the thermal resistance of the oscillator, it was found that a relatively large stray heat input (9×10−4 nW) would be needed to cause the leveling off. Further work will be needed to determine whether the leveling off is due to stray heat or intrinsic physics.
An explicit separation of relativised random polynomial time and relativised deterministic polynomial time

Inthis note, we demonstrate that a certain class of naturally occuring problems involving an oracle are solvable in random polynomial time, but not in deterministic polynomial time. This class of problems is especially interesting because a very slight change in the parameters of the problem yields one that does have a polynomial solution.
Endothelial-Fibroblast Interactions in Angiogenesis and Matrix Remodeling

Revascularization is critical for successful regeneration of ischemic cardiac tissue after injury. To achieve revascularization in engineered cardiac grafts, it is necessary to understand the interactions between major cardiac cell types. The importance of cardiomyocyte-endothelial interactions in angiogenesis is well documented [1]; however, less is known about interactions between endothelial and stromal cells, fibroblasts in particular. Studies indicate that during capillary assembly, fibroblasts (FBs) provide chemical signaling via growth factor expression and endothelial activation and proliferation [2]. In addition, fibroblasts deposit extracellular matrix (ECM) proteins [3] and also play a role in matrix remodeling. The objective of our study was to further investigate the role of endothelial-fibroblast interactions in angiogenesis with a focus on FB regulation of the extracellular mechanical environment. We and others have recently shown that self-assembling peptide nanoscaffold is a promising material for cardiac tissue regeneration, enhancing angiogenesis in vitro and promoting tissue neovascularization in vivo [1, 4–5]. An important advantage of this nanoscaffold is the ability to control its material properties, such as stiffness and rate of MMP degradation, through its sequence and/or concentration [6]. In this study, RAD16-II peptide nanoscaffold was used as a controlled system to test the hypothesis that fibroblasts regulate angiogenesis via modifying the extracellular mechanical environment through mechanisms including cell-mediated scaffold disruption and matrix remodeling.Copyright © 2009 by ASME
Population genetic structure of Nantucket pine tip moth.

Variation at polymorphic isozyme loci was analyzed in Nantucket pine tip moth (NPTM) populations from 5 geographic locations. At the North Carolina location, populations representing 3 generations at 3 local sites were also studied. Four of the loci investigated (LAP, MDH, α-GPDH and AK), although variable, had few alleles per locus (3–5) and few differences among populations in allele frequencies. At each locus, all populations had the same allele at a high frequency. At the PGM locus, fifteen alleles were identified and allelic frequencies varied among populations. At least eight alleles were present within a population and, in most populations, two or more alleles had high frequencies that differed among populations. An excess of homozygotes over Hardy-Weinberg expectations was found for 7 out of the 10 populations studied, indicating the probable existence of some form of inbreeding structure or populational subdivision within sampled stands. Joint consideration of the results observed for PGM and the other four loci is counterindicative of neutrality at all loci and strongly indicative of genetic differentiation among locally disjunct populations.
Accuracy of Personality and Social Judgments as Functions of Familiarity

This study examined the relationship between degree of familiarity with another person (intimate, casual, or nonacquaintance) and ability to make accurate social and personality predictions of that person's behavior. 3 groups of 32 male-female dyads completed either a Q- or free-sort personality judgments task and a social judgments questionnaire twice for (a) self-description and (b) prediction of dyad partner. Mean accuracy scores on both judging tasks indicated that familiarity leads to increased predictive accuracy. The results were interpreted as due to valid behavioral observations and attenuation of emotional bias arising from increased familiarity. The obtained relative superiority of free- over Q-sort accuracy scores was explained in terms of the absence of restrictions placed on the judging behavior of free-sort Ss.
Contractile responses of dendrites in the bullfrog retina.

Abstract Isolated retinae of the bullfrog were found to “contract” when excited either by electric stimulation of the optic nerve or by light stimulation of the photoreceptors. Involvement of the dendrites of the ganglion and amacrine cells in these contractile responses is suggested.
Surface-relaxation contributions to axial screw dislocation contrast in synchrotron white-beam X-ray topographs of SiC

Micropipe images appeared in synchrotron white-beam X-ray topographs of thin basal-cut SiC wafers taken using prismatic reflections where g · b = 0. They consisted of white ovals inclined along the direction of the topographs' g vector that were terminated with dark spikes at either end. The thin wafers tended to curl; the appearance of a defect's image varied depending on the sign of the curvature relative to the side serving as the diffracted beam's exit surface. The micropipe images were computer simulated using the ray-tracing method. The calculation assumed that they arose from the surface-relaxation strain component of a closed-core screw dislocation perpendicular to the surface of a thin foil. The qualitative features of the micropipe images were reproduced in their simulations, but the magnitude of the lattice misorientations predicted by the model was not large enough to account for the size of the experimentally observed dislocation images.
Multiscale turbulence effects in underexpanded supersonic jets

A modified version of the multiscale turbulence model of Hanjalic has been applied to the problem of underexpanded supersonic jets. In particular, the shock-cell decay resulting from shock-mixing layer interactions has been studied for both mildly interacting and strongly resonant jet conditions. A version of the Hanjalic model which accounts for nonequilibrium energy transfer between two spectral scales of turbulence was incorporated into an existing shock-capturing, parabolized Navier-Stokes computational model in order to perform numerical experiments. Results are presented for nominal initial jet Mach numbers of 2.0, 1.4, and 1.0 and are compared to experiments and to predictions made using single-scale models. The results show significant effects of multi-spectral turbulent energy transfer on the predicted shock-cell decay particularly for the lower jet Mach numbers.
A method to determine the available UV-C dose for the decontamination of filtering facepiece respirators.

Aims: To develop a method to assess model-specific parameters for ultraviolet-C (UV-C, 254 nm) decontamination of filtering facepiece respirators (FFRs). Methods and Results: UV-C transmittance was quantified for the distinct composite layers of six N95 FFR models and used to calculate model-specific α-values, the percentage of the surface UV-C irradiance available for the internal filtering medium (IFM). Circular coupons, excised from the FFRs, were exposed to aerosolized particles containing MS2 coliphage and treated with IFM-specific UV-C doses ranging from 38 to 4707 J m−2. Models exposed to a minimum IFM dose of 1000 J m−2 demonstrated at least a 3 log reduction (LR) in viable MS2. Model-specific exposure times to achieve this IFM dose ranged from 2 to 266 min. Conclusions: UV-C transmits into and through FFR materials. LR of MS2 was a function of model-specific IFM UV-C doses. Significance and Impact of the Study: Filtering facepiece respirators are in high demand during infectious disease outbreaks, potentially leading to supply shortages. Reuse of disposable FFRs after decontamination has been discussed as a possible remediation strategy, but to date lacks supporting scientific evidence. The methods described here can be used to assess the likelihood that UV-C decontamination will be successful for specific FFR models.
The role of Sirt1: At the crossroad between promotion of longevity and protection against Alzheimer's disease neuropathology

Sirt1, a mammalian member of the sirtuin gene family, holds great potential for promoting longevity, preventing against disease and increasing cell survival. For example, studies suggest that the beneficial impact of caloric restriction in promoting longevity and cellular function may be mediated, in part, by Sirt1 through mechanisms involving PGC-1alpha, which plays important role in the regulation of cellular metabolism and inflammatory and antioxidant responses. Sirt1 may also interfere with mechanisms implicated in pathological disorders. We will present recent evidence indicating that Sirt1 may protect against Alzheimer's disease by interfering with the generation of beta-amyloid peptides. We will discuss Sirt1 as a potential novel target, in addition to the development of Sirt1 activators for the prevention and treatment of Alzheimer's disease.
Suppressor cell population in Sézary syndrome.

Abstract In the present study, T lymphocytes from a patient with the Sezary syndrome were shown to suppress the synthesis of immunoglobulin in B lymphocytes. Immunoglobulin synthesis and secretion were measured in cultures containing lymphocytes and pokeweed mitogen. Although normal peripheral blood lymphocytes synthesized immunoglobulin in vitro, lymphocytes from the Sezary patient were incapable of immunoglobulin synthesis. After fractionation of normal and Sezary lymphocytes into T- and B-cell populations, immunoglobulin synthesis was demonstrated in cultures containing normal T and Sezary B cells, but not in cultures of Sezary T and normal B cells. When Sezary T lymphocytes were cocultured with both normal T and B cells, immunoglobulin synthesis was suppressed by 80%, compared to appropriate controls. These studies demonstrate that malignant transformation of T lymphocytes in the Sezary syndrome can result in the generation of cells which suppress immunoglobulin synthesis. Furthermore, B cells from this patient were capable of synthesizing immunoglobulin, predominantly IgA, in the presence of normal T cells.
Interpretation of male rat renal tubule tumors.

Based on an analysis of recent scientific studies, a Technical Panel of the U.S. Environmental Protection Agency`s (EPA) Risk Assessment Forum recently advised EPA risk assessors against using information on certain male rat renal tubule tumors to assess human risk under conditions specified in a new Forum report. Risk assessment approaches generally assume that chemicals producing tumors in laboratory animals are a potential cancer hazard to humans. For most chemicals, including classical rodent kidney carcinogens such as N-ethyl-N-hydroxyethylnitrosamine, this extrapolation remains appropriate. Some chemicals, however, induce accumulation of {alpha}{sub 2u}-globulin ({alpha}{sub 2u}-g), a low molecular weight protein, in the male rat kidney. The {alpha}{sub 2u}-g accumulation initiates a sequence of events that appears to lead to renal tubule tumor formation. Female rats and other laboratory mammals administered the same chemicals do not accumulate low molecular weight protein in the kidney, and they do not develop renal tubule tumors. Because humans appear to be more like other laboratory animals than like the male rat, in this special situation, the male rat is not a good model for assessing human risk. The Forum report stresses the need for full scrutiny of a substantial set of data to determine when it is reasonablemore » to presume that renal tumors in male rats are linked to a process involving {alpha}{sub 2u}-g accumulation and to select appropriate procedures for estimating human risks under such circumstances. 92 refs.« less
Convective-radiative heat transfer in the thermal entrance region of the semicircular duct with streamwise internal fins

Abstract In this paper, steady laminar forced convection and radiation heat transfer in the entrance region of an internally finned semicircular duct are analyzed. The fins are continuous and longitudinal, with zero thickness. The thermal condition imposed on the semicircular duct is of uniform temperature, both axially and peripherally. The three-dimensional energy equation is discretized and solved numerically by the method of lines (MOL). The method of momentum (MOM) is employed to consider the radiation contribution, which models the radiation in the partial differential equation, instead of the partial integrodifferential equation. The resulting equations, based on coarse grids, are numerically computed, using a Runge-Kutta subroutine. The effect of five major parameters on the thermal behavior in the entry region of the semicircular duct is discussed: radiation-conduction, N; optical thickness, τ b ; wall emissivity, e w ; number of fins, M; and ratio of fin height to duct radius, H. The variations in the mean bulk temperature and total Nusselt numbers show that heat transfer is enhanced in this geometry by both thermal radiation and fins.
Characterization of cytochrome b from Toxoplasma gondii and Qo domain mutations as a mechanism of atovaquone-resistance

Atovaquone is active in vitro against the tachyzoites of Toxoplasma gondii at nanomolar concentrations and is used clinically to treat acute cases of human toxoplasmosis. In pursuit of the mechanism of action of atovaquone against T. gondii and to understand how resistance might arise, drug-resistant mutants were generated and examined. The previously uncloned cytochrome b gene of T. gondii was cloned and sequenced from wild type and resistant strains as this was a likely candidate for the target of the drug and thus a source of resistance. Mutations are present within the cytochrome b gene of atovaquone-resistant parasites (M129L and I254L) and represent alterations in two different regions of the ubiquinol-binding pocket (Q(o) domain) of cytochrome b, suggesting that atovaquone interferes with electron transport at the cytochrome bc(1) complex in T. gondii. A structural model for how this hydroxynaphthoquinone is binding within the Q(o) domain is presented. Further analysis of the cytochrome b gene suggested that the protein may differ from other homologues by terminating within the mitochondrial membrane. Cytochrome b becomes the first complete mitochondrial gene and cognate protein to be described for T. gondii.
Effects of thermal protection methods on haptic perception

Electric DC motors that convert electric current to torque are the most common type of actuators used in haptic interfaces. However, high currents necessary to deliver large haptic forces can generate heat in the electromagnetic coils, and in the extreme can cause malfunctions due to overheating. It is therefore necessary to add thermal protection mechanisms to limit the output current. While this is a common feature of haptic devices, it is not clear what makes a superior current limiting method or what effect such limits have on haptic perception.
Disruption of synaptic transmission or clock-gene-product oscillations in circadian pacemaker cells of Drosophila cause abnormal behavioral rhythms.

To study the function of clock-gene–expressing neurons, the tetanus-toxin light chain (TeTxLC), which blocks chemical synaptic transmission, was expressed under the control of promoters of the clock genes period (per) and timeless (tim), each fused to GAL4-encoding sequences. Although TeTxLC did not affect cycling of a clock-gene product at the gross level, it disrupted the rhythmic behavior of adult Drosophila. In constant darkness, the proportion of rhythmic flies was reduced in flies expressing active TeTxLC compared to controls, including those expressing inactive toxin. The behavior of TeTxLC-expressing flies was less synchronized to light:dark cycles than that of controls. To determine which neurons are responsible for these effects on behavior, the toxin was also expressed in restricted subsets of per/tim-expressing, laterally located pacemaker neurons by expressing TeTxLC under the control of a driver in which GAL4-encoding sequences are fused to the promoter of the pigment dispersing factor (pdf) gene. pdf-gal4–driven TeTxLC expression had relatively little effect on behavioral rhythms, implying that per/tim neurons other than pdf-expressing lateral neurons participate in the generation of rhythmic behavior. In another set of experiments, period gene products were expressed under the control of per-gal4 or tim-gal4. This resulted in an increased level of PER protein in many brain cells and reduction of bioluminescence cycling reported by a per-luciferase transgene, especially in the case of per expression affected by tim-gal4. This indicates a disruption of the transcriptional feedback loop that is a part of the oscillatory mechanism underlying Drosophila's circadian rhythms. Consistent with this molecular defect, the proportion of rhythmic individuals in constant darkness was subnormal in flies expressing PER under the control of tim-gal4, and their behavior in light:dark cycles was abnormal. © 2000 John Wiley & Sons, Inc. J Neurobiol 43: 207–233, 2000
Prognostic factors associated with response in platinum retreatment of platinum‐resistant ovarian cancer

The goal of this study was to determine the factors associated with response to platinum retreatment in patients with platinum-resistant ovarian cancer. A review of patients with epithelial ovarian cancer retreated with cisplatin or carboplatin between 2002 and 2004 was performed. The platinum-free interval (PFI) and treatment-free interval (TFI) were determined for each patient. Response was based on serial CA125 levels using a modification of the Rustin criteria. Patients with clinical benefit ([CB] those who attained at least stable disease) were compared to patients with disease progression (PD). An analysis was performed to determine factors associated with CB in platinum-resistant patients retreated with platinum. Of 48 patients identified, 37 were evaluable included in this analysis. CB was observed in 27 (73%) while disease progression was noted in 10 (27%) women. The PFI was longer in those women who achieved CB (12.3 vs 6.9 months; P = 0.02). The TFI was 7.1 months for patients benefited from platinum retreatment vs 3.5 months for those with disease progression (P = 0.06). There was no statistically significant difference in the number of cytotoxic agents between the time of platinum retreatment and the prior platinum regimen (2 vs 1.5 months; P = 0.61). A prolonged PFI was associated with an improved chance of achieving CB with platinum retreatment. There was no association between the response to platinum retreatment and the number of intervening cytotoxic agents utilized. Further prospective study is warranted to define the optimal timing of platinum retreatment.
Black and Female Municipal Employment: A Substantive Benefit of Minority Political Incorporation?

Research has advanced the expectation that black political mobilization will result not only in gains in black descriptive representation but also change in public policy. Under the premise that city employment is a substantive benefit, this article documents the relationships between mayoral leadership, minority descriptive representation on the city council, and trends in black and female municipal employment across eight job categories in New Orleans, Louisiana rom 1978 through 1997. It is hypothesized that with growing minority political incorporation there will occur a distinct and identifiable temporal sequence in minority city employment gains across several job categories dependent upon the relative desirability of those jobs. Over the period studied the following is found: (1) patterns of racial job stratification based on job desirability, (2) distinct trends in black male and black female employment, (3) male-female differences in traditional gender-specific occupations, and (4) bifurcation of black female and non-black female employment trends in gender-specific occupations. Although black political incorporation was in its ascendancy through the 1980s and public policy has been substantially controlled by the black leadership for more than a decade, the realization of substantive benefits in the form of municipal jobs has been much slower than previously theorized.
Unique tryptic peptides specific for bovine and human hemoglobin in the detection and confirmation of hemoglobin-based oxygen carriers.

Hemoglobin-based oxygen carriers (HBOCs) of bovine hemoglobin (Hb) or human Hb origin were developed for replacement or augmentation of blood during transfusion and have the potential to increase oxygen-carrying capacity of circulating blood and thus improve tissue oxygen delivery. Due to their potential for increasing oxygen-carrying capacity of circulating blood, they are excellent candidates for abuse in human and equine athletes. To deter athletes from blood doping with HBOCs such as Hemopure and Oxyglobin (OXY), a method for detection, confirmation, quantification, and distinguishing of HBOCs from native hemoglobin in test samples is needed. The purpose of this study was to identify unique peptides specific for bovine Hb and human Hb that are useful in the detection and confirmation of HBOCs in test samples. The LC−MS chromatographic peak profiles of tryptic digests from OXY, bovine Hb, human Hb, and equine Hb were compared, and unique tryptic peptides specific for bovine Hb, human Hb, and equine Hb ...
Tannic acid‐glutaraldehyde fixation reveals calcium ionophore‐induced changes in rabbit polymorphonuclear leukocyte membranes

TAG fixation of normal and Ca2+ ionophore-treated rabbit polymorphonuclear leukocytes (PMN) has revealed membrane components not apparent with conventional glutaraldehyde fixation. These included a 30 A external electron-dense coating on untreated cells. A somewhat thicker coat (40 A) was observed in ionophore-treated, nondegranulating PMN. In ionophore-treated, degranulating PMN, a 65 A cell membrane coat was observed. A similar coat was observed on the inner side of the membrane of some azurophil-type granules, but the electron density and thickness were not so pronounced. Cytoplasmic granules were often closely apposed and often protruded outward at the plasma membrane. Extracellular lamellae, sometimes stacked apposed to the plasma membrane, possibly represent remnants of intense granule extrusion. Sequential degranulation of the respective granules was not apparent.
Immunological identification of rat neurophysin precursors.

NEURONES in the supraoptic and paraventricular nuclei of the hypothalamus synthesise two peptide hormones, vasopressin and oxytocin. These hormones and their neurophysin ‘carrier’ proteins are stored in (and released from) nerve endings in the posterior lobe of the pituitary1–3. On the basis of extensive studies of the synthesis of vasopressin in vivo and in vitro, Sachs et al.4–8 have suggested that vasopressin and its associated neurophysin are synthesised as parts of a common precursor by a ribosomal mechanism. We have also presented evidence that the neurophysins are synthesised as parts of larger precursor molecules9,10. These 20,000 molecular weight precursors seem first to give rise to 17,000 molecular weight intermediates which, in turn, yield the 12,000 molecular weight neurophysins. The following data show that the putative neurophysin precursors and intermediates bind specifically to anti-rat neurophysin antiserum.
The significance of intramedullary cancellous bone formation in the repair of bone marrow tissue

The repair of hemopoietic bone marrow following evacuation of the tibial or femoral cavity of the rat was sequentially studied with the light microscope. A stereotyped train of histologic events occurred. These were capillary invasion of the cavity, appearance of primitive mesenchymal cells, osteoblastic proliferation, cancellous bone formation, development of sinusoids, reappearance of hemopoietic tissue and resorption of cancellous bone. The studies suggest that restoration of marrow sinusoids takes place only in the interstices of cancellous bone. Mechanical disruption of the sinusoidal system is one method of triggering cancellous bone formation. The cancellous bone which appeared after injury was thought to be produced by endosteal osteoblasts and osteoblasts derived from cells residing in normal hemopoietic tissue. Localized radiation of the tibia followed by mechanical disruption of hemopoietic tissue demonstrated that cancellous bone production and the repair process were unimpaired by 1,000 r but were completely blocked by 4,000 r. This would imply that the cell which can differentiate into an osteoblast is resistant to 1,000 r.
Incorporating positive psychology content and applications into various psychology courses

Courses devoted to the subject of positive psychology are becoming more common in colleges and universities throughout the United States and beyond, however, there are still many schools that do not have a positive psychology course as part of the psychology curriculum. This article was designed for instructors in such settings who desire to teach positive psychology, but do not have access to a course specifically on this topic or for those who already teach a positive psychology course but desire to implement positive psychology topics into other psychology courses as well. Although the recommendations in this article are not exhaustive in terms of covering all psychology courses and all aspects of positive psychology that have applications to these courses, the material provided should stimulate thinking about the various ways in which positive psychology can be infused into courses that are not entirely dedicated to the topic.
Influence of smooth muscle tone and longitudinal tension on the collapsibility of immature airways.

Mechanical properties and pressure-flow relationships of tracheae excised from very premature lambs were studied in a plethysmograph. Control (Group I) data revealed the tracheae to be extremely compliant, collapsible airways, with an inflation compliance (Si) of 0.033 (+/- 0.004 SE) mmHg-1, collapsing compliance (Sc) of 0.026 (+/- 0.001 SE) mmHg-1, and pressure-flow relationships similar to those of a Starling resistor. Acetylcholine administration (Group II) lowered both Si, 0.026 (+/- 0.003 SE) mmHg-1 and Sc, 0.022 (+/- SE) mmHg-1, as did longitudinal stretch (Group III): Si, 0.021 (+/- .003 SE) mmHg-1, and Sc, 0.017 (+/- 0.002 SE) mmHg-1. Alterations in tracheal collapsibility were also evidenced by significant reductions in resistance to airflow when the tracheae were subjected to compressive forces. Altering both smooth muscle tone (acetylcholine administration) and longitudinal length simultaneously (Group IV) produced results similar to those obtained for Group III. These data help to define the functional characteristics of immature airways and may provide insight for more effective clinical management of the premature infant.
Towards Efficient and Compact Phenomenological Representation of Arbitrary Bidirectional Surface Reflectance

The visual appearance of real-world surfaces is the net result of surface reflectance characteristics when exposed to illumination. Appearance models can be constructed using phenomenological models which capture surface appearance through mathematical modeling of the reflection process. This yields an integral equation, known as reflectance equation, describing the surface radiance, which depends on the interaction between the incident light field and the surface bidirectional reflectance distribution function (BRDF). The BRDF is a function defined on the cartesian product of two hemispheres corresponding to the incident and outgoing directions; the natural way to represent such a hemispherical function is to use hemispherical basis. However, due to their compactness in the frequency space, spherical harmonics (SH) have been extensively used for this purpose. In this paper, we address the geometrical compliance of hemispherical basis for representing surface BRDF. We propose a tensor product of the hemispherical harmonics (HSH) to provide a compact and efficient representation for arbitrary BRDFs, while satisfying the Helmholtz reciprocity property. We provide an analytical analysis and experimental justification that for a given approximation order, our proposed hemispherical basis provide better approximation accuracy when compared to Zernike-based basis, while avoiding the high computational complexity inherited from such polynomials. We validate our proposed Helmholtz HSH-based basis functions on Oren-Nayar and Cook-Torrance BRDF physical models.
Jehoshaphat and His Prayer among Sixteenth-Century Lutherans

Martin Luther, writing in his Betbuchlein in 1522, declared:Among the many harmful books and doctrines which are misleading and deceiving Christians and give rise to countless false beliefs, I regard the personal prayer books as by no means the least objectionable. They drub into the minds of simple people such a wretched counting up of sins and going to confession, such un-Christian tomfoolery about prayers to God and his saints! Moreover, these books are puffed up with promises of indulgences. … These books need a basic and thorough reformation if not total extermination.… But I just don't have the time to undertake such a reformation; it is too much for me alone.
Comparison of Molecular Simulation and Pseudo-Rigid-Body Model Predictions for a Carbon Nanotube–Based Compliant Parallel-Guiding Mechanism

We report on the accuracy of the pseudo-rigid-body model (PRBM) in predicting the behavior of a nanoscale parallel-guiding mechanism (nPGM) that uses two single-walled (5,5) carbon nanotubes (CNTs) as the flexural guiding elements. The nPGM has two regions of behavior: region I is governed by the bulk deformation of the nanotubes, and region 2 is characterized by hingelike flexing of four "kinks" that occur due to buckling of the nanotube walls. PRBM parameters for (5,5) CNTs are proposed. Molecular simulation results of region I behavior match PRBM predictions of (I) kinematic behavior with less than 7.3% error and (2) elastomechanic behavior with less than 5.7% error. Although region I is of more interest because of its well-defined and stable nature, region 2 motion is also investigated. We show that the PRBM parameters are dependent on the selection of the effective tube thickness and moment of inertia, the lesson being that designers must take care to consider the thickness and moment of inertia values when deriving PRBM constants.
Hipponax and His Enemies in Ovid's Ibis

Among the many textual difficulties that beset Ovid's Ibis are two passages that allude, in an oblique fashion typical of the whole poem, to the iambographer Hipponax: (1) et quae Pytheides fecit de fratre Medusae, eveniant capiti vota sinistra tuo, (447–8 La Penna) (2) utque parum stabili qui carmine laesit Athenin, invisus pereas deficiente cibo. (523–4 La Penna)
CHLOROPHYLL a:b RATIOS IN MARINE PLANKTONIC ALGAE1

Chlorophyll a:b ratios for Chlorella capsulata Guillard, Bold & MacEntee, Chlorosarcinopsis halophila Guillard, Bold,& MacEntee, Nannochloris atomus Butcher and Micromonas pusilla (Butcher) Manton & Parke were found to be 1.74, 2.46, 1.89, and 1.53, respectively. Compared to previously published values in marine planktonic algae, these ratios are similar to the average value (2.17, SD = 1.12) reported for 25 species in 15 genera. Both the new data and previously published data support the hypothesis that marine algae have lower chlorophyll a:b ratios than do other chlorophyll b containing plants.