cssi/SciSciGPT-SciSciNet huggingface dataset:
Fast and accurate solution of time domain electric field integral equation for dielectric half-space

In this work, an FFT-accelerated MOT solver is used to analyze broadband scattering phenomena in a half-space environment. The multilevel space-time FFT scheme accelerates both the matrix-fill and marching times by exploiting the translational invariance of the underlying integral kernel through the use of uniform spatial meshes. All time domain Green's functions are computed by inverse Fourier transforming their frequency domain counterparts, which, in turn, are computed by adaptive evaluation of Sommerfeld integrals. In what follows, the proposed method is applied to the analysis of transient scattering from PEC bodies residing above a dielectric half-space. The method is flexible enough to be used in the analysis of layered media with more complicated Green's functions and can be extended to nonuniformly meshed scatterers using the time domain adaptive integral method.
Analysis of ONEDANT code package for the calculation of the Doppler coefficient of reactivity

The viability of the use of the ONEDANT discrete ordinates code for the calculation of the Doppler coefficient of reactivity for a pressurized water reactor is investigated. The ONEDANT results are compared with benchmark results from a Monte Carlo code, MCNP-3A. A comparison with the results obtained using the CELL-2 and WIMS-AECL codes is also included. The influences of certain variables, such as spatial mesh, S[sub N] angular quadrature order, interaction convergence criterion, boundary conditions, P[sub N] order, and number of energy groups, are analyzed. An alternative benchmark calculation to the Monte Carlo result is attempted to provide some feel for the approximate accuracy of the Monte Carlo calculation. Such an alternative answer is important when less approximate methods are compared with these results.
Potassium Hydrogen Sulfide

[1310-61-8] HKS (MW 72.18) InChI = 1S/K.H2S/h;1H2/q+1;/p-1 InChIKey = ZOCLAPYLSUCOGI-UHFFFAOYSA-M (a nucleophile and reducing agent similar to NaSH; useful in the synthesis of thiols,1 thioethers,2 and thiocarbonyl compounds3) Physical Data: mp 455 °C; d 1.68–1.70 g cm−3. Solubility: very sol H2O; sol EtOH. Form Supplied in: commercially available as a crystalline solid; colorless when pure. May be contaminated with K2S2O3 and K2CO3. Preparative Method: saturation of ethanolic KOH by H2S.4 Handling, Storage, and Precautions: extremely hygroscopic. Darkens on heating to yellow, then deep red at mp. Aqueous solutions evolve H2S on heating (KSH + H2O  KOH + H2S), and decompose in air to polysulfides and H2S. Oxygen also yields K2S2O3 and traces of K2SO3. Carbon dioxide yields H2S and K2CO3. For other precautions and toxicity see Sodium Hydrogen Sulfide.
FLAMMABILITY OF AEROSOLS GENERATED BY A ROTARY ATOMIZER

Flammability of aerosols of hydrocarbon liquids was studied using a spinning disk atomizer, which simulates accidental aerosolization of a fuel from an aircraft. We determined the critical droplet sizes and fuel flow rates (or mass flux) needed to create an aerosol mixture that forms a stable flame upon ignition. At lower droplet sizes or higher flow rates than the critical values the aerosol mixtures were flammable. The critical flow rate increases with the droplet size for JP5 and are lower by a factor of 3 to 5 for heptane. The flammability diagram enables a quantitative comparison of different liquids in aerosol form. This is significantly different from the thermodynamic behavior of a liquid pool, which is dictated by the flash point or vapor pressure.
Pharmacogenetic testing: not as simple as it seems

Pharmacogenetics has the potential to help guide treatment decisions by tailoring appropriate drugs and dosages to patients most likely to benefit. This straightforward clinical goal has led some to suggest that pharmacogenetic testing is free of ethical concerns. However, a number of potential risks and clinical uncertainties arise in considering the use of these new tools in clinical care. We propose a classification of pharmacogenetic tests to identify and prioritize the policy issues that will need to be addressed to ensure appropriate delivery of pharmacogenetic testing. We use the classification framework to consider the benefits and risks associated with ancillary information, timing of testing, and storage and retrieval of pharmacogenetic test results among health professionals. These issues have implications for informed consent and genetic counseling requirements, and for the role of health professionals.
Colitis induced destruction of the tight junction (TJ) protein ZO-1 is IL-4/Stat6 dependent

Abstract Introduction: The TJ, which helps regulate the intestinal permeability (IP) barrier, is composed of both cytosolic proteins such as ZO-1 and transmembrane proteins such as claudin-1. Increased IP is present in intestinal inflammation. Stat6 regulates cytokine induced gene expression through the IL-4-Stat6 signaling pathway and may be involved in intestinal inflammation. Hypothesis: TJ expression is decreased in dextran sodium sulfate (DSS) induced colitis. Methods: Balb/c and Stat6 knockout (Stat6)- mice were fed 3–4% DSS in their water. Control animals received water. Animals were weighed and stool was checked for blood. On day 7 animals were sacrificed, the colon measured, and segments embedded in paraffin for histology. Colonic mucosa was harvested and assayed quantitatively by Western blot using a monoclonal antibody to ZO-1 and claudin-1. Results: DSS treated animals had heme positive stools, colitis by histology, significant weight loss and colon shortening (table) . TABLE—ABSTRACT 87 . Control Balb/c Control Stat6- DSS Balb/c DSS Stat6- % Wt gain 2.0 ± 0.5 −0.8 ± 1.0 −11.9 ± 1.8 ∗ −14.8 ± 2.1 ∗ Colon (cm) 8.37 ± 0.14 9.83 ± 0.22 6.44 ± 0.35 ∗ 6.52 ± 0.27 ∗ Mean ± standard error, ∗ P There were no differences between Balb/c and Stat6- DSS treated animals. There was an absence of ZO-1 in the Balb/c DSS treated animals but normal levels in the Stat6- DSS treated animals (figure). There were no changes in claudin-1 expression with DSS treatment in either mouse type. Conclusions: 1: DSS ingestion caused weight loss, colonic shortening, bloody diarrhea and colitis. 2: These findings were the same in both the Balb/c and Stat6- mice. 3: ZO-1, but not claudin-1, was absent in the DSS treated Balb/c mice suggesting that the inflammatory process destroyed ZO-1. 4: An intact IL-4-stat6 activation pathway is necessary for colitis induced disruption of ZO-1 because Stat6- DSS treated mice did not show a decrease in ZO-1. IL-4 may be responsible for the disruption of ZO-1 in this model. Download : Download high-res image (61KB) Download : Download full-size image
Geometric constraints and stereo disparity computation

Most stereo techniques compute disparity assuming that it varies slowly along surfaces. We quantify and justify this assumption, using weak assumptions about surface orientation distributions in the world to derive the density of disparity surface orientations. The small disparity change assumption is justified by the orientation density's heavy bias toward disparity surfaces that are nearly parallel to the image plane. In addition, the bias strengthens with smaller baselines, larger focal lengths, and as surfaces move farther from the cameras. To analyze current stereo techniques, we derive three densities from the first density, those of the disparity gradient magnitude, the directional derivative of disparity, and the difference in disparity between neighboring surface points. The latter may be used in Bayesian algorithms computing dense disparity fields. The directional derivative density and the disparity difference density both show that feature-based algorithms should strongly favor small disparity changes, contrary to several well-known algorithms. Finally, we use our original surface orientation density and the gradient magnitude density to derive two new “surfaces-from-stereo” techniques, techniques combining feature-based matching and surface reconstruction. The first uses the densities to severely restrict the search range for the optimum fit. The second incorporates the surface orientation density into the optimization criteria, producing a Bayesian formulation. Both algorithms are shown to be efficient and effective.
The asymptotic expansion of certain canonical integrals

Abstract Integrals of the form I(λ) = ∝ R 2 ƒ( x ) exp {iλφ( x )} d x , common in diffraction theory, are usually evaluated asymptotically for large λ using the stationary phase technique. At caustic points the classical technique is not applicable. A computation-oriented algorithm is developed for determining the asymptotic expansion of such integrals with φ( x ) a Thom umbilic, the canonical form appropriate at caustic points for most cases of physical interest.
A comparison of fuzzy and nonparametric linear regression

Nonparametric linear regression and fuzzy linear regression have been developed based on different perspectives and assumptions, and thus there exist conceptual and methodological differences between the two approaches. This article describes their comparative characteristics such as basic assumptions, parameter estimation, and applications, and then compares their predictive and descriptive performances by a simulation experiment to identify the conditions under which one method performs better than the other. The experimental results indicate that nonparametric linear regression is superior to fuzzy linear regression in predictive capability, whereas their descriptive capabilities depend on various factors. When the size of the data set is small, error terms have small variability, or when the relationships among variables are not well specified, fuzzy linear regression outperforms nonparametric linear regression with respect to descriptive capability. The conditions under which each method can be used as a viable alternative to the conventional least squares regression are also identified. The findings of this article would be useful in selecting the proper regression methodology to employ under specific conditions for descriptive and predictive purposes.
Bistable lasing wavelength in a mode-locked two-section quantum-dot diode laser

We report a two-section mode-locked quantum dot laser with an emission wavelength that is bistable with respect to applied reverse bias on the saturable absorber region.
Trophic relationships of deep-sea calanoid copepods from the benthic boundary layer of the Santa Catalina Basin, California

Abstract Benthopelagic zooplankton were collected and preserved in situ in the benthic boundary layer of the Santa Catalina Basin, using a multiple sampling opening-closing net system attached to the DSRV Alvin . Gut content analysis performed with transmission electron microscopy (TEM) showed that the majority of benthopelagic calanoid copepods examined were predominantly detritivores. They had ingested detritus and associated bacteria, including metal-precipitating bacteria; no attached enteric bacteria were observed in the copepods' guts. The gut particles indicated generalized feeding and qualitatively resembled material present in the environment at the time of collection, i.e. suspended particles, large fecal pellets, particles from the surface layer of the sediment, and phaeodia of phaeodarian radiolarians. TEM was necessary for identifying some of the amorphous material in copepod guts as either digested tissue or detrital material; some of the amorphous material was unidentifiable even with the resolution of TEM. TEM was also essential for detecting metal-precipitating bacteria and their capsules from the copepod guts and from particles in the water. Because they ingest metal-precipitating bacteria, detritivorous copepods may influence the distribution of metals in the ocean.
Fine needle aspiration biopsy in malignant obstructive jaundice

Percutaneous cytodiagnosis of malignancy in patients with biliary tract obstruction is often useful in planning subsequent therapy. Of 121 patients presenting for percutaneous transhepatic cholangiography and biliary drainage, 45 had fine needle aspiration biopsies. Forty-one patients had malignant obstruction of the biliary tree, while benign disease was present in 4 patients. Neoplasia was diagnosed in 12 of 13 patients with bile duct carcinoma, 16 of 22 patients with pancreatic cancer, and 3 of 6 patients with other malignancies. Radiologic biopsy sensitivity was only slightly inferior to surgical biopsy sensitivity in the same patient population. A scheme for biliary cytodiagnosis is presented, which uses a percutaneous approach for patients with suspected pancreatic carcinoma and a transcatheter approach for patients with suspected bile duct carcinoma. The utility of this procedure and the low complication rate are stressed.
Roles of Ionic Residues of the C1 Domain in Protein Kinase C-α Activation and the Origin of Phosphatidylserine Specificity

On the basis of extensive structure-function studies of protein kinase C-α (PKC-α), we have proposed an activation mechanism for conventional PKCs in which the C2 domain and the C1 domain interact sequentially with membranes (Medkova, M., and Cho, W. (1999) J. Biol. Chem. 274, 19852–19861). To further elucidate the interactions between the C1 and C2 domains during PKC activation and the origin of phosphatidylserine specificity, we mutated several charged residues in two C1 domains (C1a and C1b) of PKC-α. We then measured the membrane binding affinities, activities, and monolayer penetration of these mutants. Results indicate that cationic residues of the C1a domain, most notably Arg77, interact nonspecifically with anionic phospholipids prior to the membrane penetration of hydrophobic residues. The mutation of a single aspartate (Asp55) in the C1a domain to Ala or Lys resulted in dramatically reduced phosphatidylserine specificity in vesicle binding, activity, and monolayer penetration. In particular, D55A showed much higher vesicle affinity, activity, and monolayer penetration power than wild type under nonactivating conditions,i.e. with phosphatidylglycerol and in the absence of Ca2+, indicating that Asp55 is involved in the tethering of the C1a domain to another part of PKC-α, which keeps it in an inactive conformation at the resting state. Based on these results, we propose a refined model for the activation of conventional PKC, in which phosphatidylserine specifically disrupts the C1a domain tethering by competing with Asp55, which then leads to membrane penetration and diacylglycerol binding of the C1a domain and PKC activation.
Otto Hahn: Responsibility and Repression

The role that Otto Hahn (1879–1968) played in the discovery of nuclear fission and whether Lise Meitner (1878–1968) should have shared the Nobel Prize for that discovery have been subjects of earlier studies, but there is more to the story. I examine what Hahn and the scientists in his Kaiser Wilhelm Institute for Chemistry in Berlin-Dahlem did during the Third Reich, in particular, the significant contributions they made to the German uranium project during the Second World War. I then use this as a basis for judging Hahn’s postwar apologia as the last president of the Kaiser Wilhelm Society and first president of its successor, the Max Planck Society.
THE MANAGEMENT OF VIOLENCE BY POLICE PATROL OFFICERS

This study examines the dynamics of potentially violent encounters between police and public. It is based on systematic observation of about 350 eight-hour tours of duty by patrol officers in three precincts of New York City during the summer of 1986. It compares the tactics and resulting outcomes found in encounters handled, respectively, by patrol officers believed by their peers to be especially skilled at minimizing violence and a cross section of all other patrol officers. Its major conclusions are (1) violence, even verbal aggression, is relatively rare in police work: (2) most conflict is dampened by the arrival of the police, leaving little scope for the use of defusing tactics: and (3) the behavior of officers judged by colleagues to be skilled in minimizing violence is measurably different from the behavior of “average” patrol officers, and in ways that suggest that colleagues may be good judges of on-street performance.
SUSTAINABLE TRANSPORTATION AND LAND DEVELOPMENT ON THE PERIPHERY: A CASE STUDY OF FREIBURG, GERMANY AND CHULA VISTA, CALIFORNIA

Abstract This paper examines two land developments in the cities of Freiburg (Germany) and Chula Vista (California) with the purpose of comparing their transportation and land use planning institutions, processes, and actions for the importance placed on achieving sustainability. Planning practitioners in both places are committed to concepts of sustainability, but their respective attempts to achieve sustainability differ dramatically. Freiburg is pursuing relatively high density land development in conjunction with transit service, while Chula Vista is pursuing relatively low-density, auto-oriented land development patterns.
Production of scalar leptons in W- and Z-boson decay

Alternative decay modes of the W and Z bosons may provide a method either to discover the supersymmetric partners of leptons or to set greatly improved limits on their masses. Details are provided on these methods, and various distributions are shown for separating potential backgrounds. If p-barp..-->..W..-->..e/sub s/..nu../sub s/ is allowed, a clear signal for supersymmetry could be established from future data. In e/sup +/e/sup -/ annihilation a distinctive signature for scalar neutrinos could be jets plus an electron all confined to a single hemisphere (with substantial missing energy). Even more dramatic but rarer would be events with only e/sup +/+..mu../sup -/ together in one hemisphere and all other energy missing.
Assessment of clinical analytical sensitivity and specificity of next-generation sequencing for detection of simple and complex mutations

Detecting mutations in disease genes by full gene sequence analysis is common in clinical diagnostic laboratories. Sanger dideoxy terminator sequencing allows for rapid development and implementation of sequencing assays in the clinical laboratory, but it has limited throughput, and due to cost constraints, only allows analysis of one or at most a few genes in a patient. Next-generation sequencing (NGS), on the other hand, has evolved rapidly, although to date it has mainly been used for large-scale genome sequencing projects and is beginning to be used in the clinical diagnostic testing. One advantage of NGS is that many genes can be analyzed easily at the same time, allowing for mutation detection when there are many possible causative genes for a specific phenotype. In addition, regions of a gene typically not tested for mutations, like deep intronic and promoter mutations, can also be detected. Here we use 20 previously characterized Sanger-sequenced positive controls in disease-causing genes to demonstrate the utility of NGS in a clinical setting using standard PCR based amplification to assess the analytical sensitivity and specificity of the technology for detecting all previously characterized changes (mutations and benign SNPs). The positive controls chosen for validation range from simple substitution mutations to complex deletion and insertion mutations occurring in autosomal dominant and recessive disorders. The NGS data was 100% concordant with the Sanger sequencing data identifying all 119 previously identified changes in the 20 samples. We have demonstrated that NGS technology is ready to be deployed in clinical laboratories. However, NGS and associated technologies are evolving, and clinical laboratories will need to invest significantly in staff and infrastructure to build the necessary foundation for success.
Alternating copolymerization of carbon monoxide and α-olefins

Pd++ catalysts with bis(diphenylphosphino)alkane ligand and methanol as coinitiator were found to be very active for the alternating copolymerization of carbon monoxide with propylene, butene-1 and hexene-1. The catalysts with bis(diphenylphosphino) propane and butane have the highest polymerization activities but only modest regiospecificity. The chiral (-)-2, 3-0-isopropylidene-2,3-dihydroxy-1,4-bis(diphenylphosphino)butane-Pd catalyst has good activity as well as regioselectivity to produce semi-crystalline CO/propylene alternating copolymer.
How Undergraduates Perceive Their Professors: A Corpus Analysis of Rate My Professor:

While many may disparage the online website Rate my Professor, it remains a popular public evaluation site for students to post their evaluations and commentary on their professors. What implications can be drawn about students' perceptions of instruction and what are the implications of students' perceptions for professors and their work? Using the folk pedagogy theory of Jerome Bruner, I examine students' perceptions of what constitutes quality instruction as expressed on the Rate My Professor website. Issues attendant to the worldwide cultural embrace of public evaluation are also examined. The extant research on the validity of traditional student evaluations, the debate on Rate My Professor's validity, and the cultural phenomenon of academic consumerism are examined. Simple concordancing is used to analyze the language of student evaluations and how forms of folk pedagogy concerning quality education are expressed. Results suggest that students favor professors who are demanding, yet helpful and atte...
Response of mice to certain avirulent bacteria after exposure to sublethal total body X-irradiation.

ConclusionsIn these experiments, death was associated with bacteremia. When avirulent live bacteria were injected, the recovered organisms were either of the strain inoculated, or were apparently autogenous bacteria. However, when heat-killed bacteria were introduced, the recovered organisms were of autogenousorigin only. It is known that bacteremia, identified with normal bowel inhabitants, is often an integral part of the syndrome observed in animals dying from whole body irradiation. In this instance, however, bacteremia and death were induced in animals exposed to sublethal doses of irradiation and subsequently inoculated with live avirulent, or even dead organisms generically different from the bacteria normally present in the intestines of these animals. This observation may be of importance under conditions where irradiation is a factor and vaccination is indicated.
Influence of time, temperature and platelet concentration on dog platelet aggregation.

Abstract Previously encountered variability in platelet aggregation responses in laboratory and clinical investigations prompted this study of common physical factors that affect aggregability of platelets (specifically, canine platelets). Valid comparison of platelet responses under the various conditions of this study was made possible by calibrating the aggregometer-recorder system using the method described below. Using this technique a direct relationship was found between platelet concentration and the amplitude of the aggregation response. For the first 90 min after venepuncture, the magnitude of platelet aggregation was stable, but deterioration in platelet aggregability occurred after two hr in vitro. Choice of short-term (one hr) storage temperature affected the amplitude of aggregation induced by 30 uM epinephrine (EPI), but not by 21 uM adenosine diphosphate (ADP). EPI-induced aggregation was significantly greater after short term storage at room temperature (20°C) than after storage at freezing (0°C) or body (37°C and 40°C) temperatures. Comparing aggregating agents, the average amplitude of aggregation in response to ADP was significantly greater than to EPI even though, in administering equal weights of agents per volume of platelet rich plasma (PRP), the resulting molar concentration of EPI was stronger than that of ADP (30 uM EPI vs 21 uM ADP).
Host induction by transplanted neural stem cells in the spinal cord: further evidence for an adult spinal cord neurogenic niche.

Aim: To explore the hypothesis that grafts of exogenous stem cells in the spinal cord of athymic rats or rats with transgenic motor neuron disease can induce endogenous stem cells and initiate intrinsic repair mechanisms that can be exploited in amyotrophic lateral sclerosis therapeutics. Materials & methods: Human neural stem cells (NSCs) were transplanted into the lower lumbar spinal cord of healthy rats or rats with transgenic motor neuron disease to explore whether signals related to stem cells can initiate intrinsic repair mechanisms in normal and amyotrophic lateral sclerosis subjects. Patterns of migration and differentiation of NSCs in the gray and white matter, with emphasis on the central canal region and ependymal cell-driven neurogenesis, were analyzed. Results: Findings suggest that there is extensive cross-signaling between transplanted NSCs and a putative neurogenic niche in the ependyma of the lower lumbar cord. The formation of a neuronal cord from NSC-derived cells next to ependyma sugge...
The Impact of Using UPFC on Jordanian Power System Performance

This paper implements base and contingency cases analysis for Jordanian transmission system using software package (PSS/E) to study the impact of inclusion the Unified Power Flow Controller (UPFC) in the Jordanian power system under different levels of power exchange with Egyptian and Syrian power systems. The studies emphasize the ability to maintain safety and efficient operations of the transmission system on both steady state and transient conditions. It also investigates the possibility to improve the overall performance of the power system and strengthen its ability to solve some stability issues within the Mediterranean Ring that connects electric power transmission grids among the countries that encircle the Mediterranean Sea.
An experimental survey of rust preventives in water III. Some general results

The influence of pH, apart from the case of amines discussed in Part II,1 and geometrical factors on the inhibition thresholds for mild steel in non-acid aqueous solutions containing dissolved air, are described. Modifying the standard corrosion tests by partial or complete removal of the air-formed oxide film increased the inhibition threshold concentration with some but not all inhibitors. Conversely, pre-immersing the specimen in an inhibiting solution reduced the threshold value below the normal value. Substances which form soluble iron complexes, such as catechol and EDTA, were often found to increase the inhibition threshold for mild steel, but the results nevertheless indicate that inhibition is not necessarily associated with the deposition of an insoluble iron salt. The iron complex solutions were themselves found to inhibit in some instances, a fact probably relevant to the well-known inhibition effect of tannins. Generally no marked differences appeared in the threshold values for a number of irons and low alloy steels. Azide showed a resemblance to nitrite in its behaviour, which suggests a similar inhibition process, i.e. adsorption. The cast irons, especially the ferritic varieties, were considerably more difficult to inhibit. Many inhibitors for ferrous materials were also found to inhibit zinc corrosion, which indicates that unfilled electron energy bands or vacant atomic orbitals are not necessary for inhibition to occur. The results described in the three papers of this series are summarised, and a novel hypothesis is presented by one of us (P.H.) to account for inhibition by anions.
Cross-coupling and stability of non-linear stochastic control systems

A frequency domain stability criterion for cross-coupled symmetrical two-dimensional nonlinear stochastic systems is presented. It has been shown that tho effect of additivo white gaussian noise is to make the system less stable. A simple geometric interpretation of tho criterion is presented.
Radioactive Myoinositol: Incorporation into Streptomycin

Radioactive myoinositol was rapidly incorporated into streptomycin by Streptomyces griseus. All the incorporated radioactivity was found in the streptidine moiety of the antibiotic, as shown by chemical degradation of the streptomycin. To a certain extent inositol reversed the depressing effect of phosphate on the production of the antibiotic.
Neighborhood Socioeconomic Environment and Sexual Network Position

Rates of sexually transmitted infections (STIs) are strongly associated with neighborhood poverty; however, the mechanisms responsible for this association remain unclear. Using a population-based study of sexual networks among urban African American adolescents, we tested the hypothesis that poverty, unemployment, and the sex ratio drive STI rates by affecting sexual network structure. Participants were categorized as being in one of three network positions that had previously been found to be strongly linked to infection with chlamydia and gonorrhea: being in a confirmed dyad (i.e., a monogamous pair), being connected to a larger network through one partner, and being in the center of a larger network. We found that only poverty was statistically significantly associated with sexual network position. Residing in the poorest third of neighborhoods was associated with 85% decreased odds of being in confirmed dyads. There was no association of sexual network position with neighborhood employment. Living in a neighborhood with an unequal number of young men and women appeared to be associated with a higher likelihood of being in a confirmed dyad; however, the differences were not statistically significant. These results suggest that poverty may impact STI rates by shaping sexual network structure, but we did not find any evidence that this association operates through unemployment or the sex ratio.
Role of TRPV1 and cannabinoid CB1 receptors in AM 404-evoked hypothermia in rats.

Abstract AM 404 inhibits endocannabinoid uptake and enhances the cannabinoid CB 1 -mediated effects of endogenous cannabinoids. Accumulating evidence also suggests that AM 404 acts at sites other than the endocannabinoid system. One site is the transient receptor potential vanilloid 1 cation channel (TRPV1). A useful endpoint for discriminating between TRPV1- or CB 1 -mediated effects of AM 404 is hypothermia. This is because TRPV1 or CB 1 receptor activation produces a significant hypothermia in rats. The present study investigated the effects of AM 404 (1, 5, 10 and 20 mg/kg, i.p.) on body temperature in rats and the involvement of TRPV1 and CB 1 receptors in the effects of AM 404. Doses of 10 and 20 mg/kg of AM 404 produced significant hypothermia. Pre-treatment with capsazepine (30 mg/kg, i.p.) blocked the hypothermia caused by 10 and 20 mg/kg of AM 404. Pre-treatment with SB 366791 (2 mg/kg, i.p.), a new TRPV1 antagonist, also abolished the hypothermia evoked by AM 404 (20 mg/kg, i.p.). In contrast, pre-treatment with SR 141716A (Rimonabant), a CB 1 antagonist, or AA-5-HT, a fatty acid amide hydrolase (FAAH) blocker, did not affect AM 404-evoked hypothermia. The present data demonstrate that AM 404 evokes a significant hypothermia in rats that is dependent on TRPV1 receptor activation.
Vortex dynamics and persistent current decay in thin superfluid /sup 4/He films

A systematic analysis of vortex dynamics based on the Kosterlitz-Thouless theory for two-dimensional phase transitions is carried out to study theoretically the decay of persistent current in thin superfluid helium films. The relaxation of vortex density due to both bulk and edge processes is considered in parallel with the dissipation of persistent current. The relaxation effects are shown to be important for thin films where bulk processes dominate, but not for thick films with prevailing wall processes. The pinning-center effects are studied within a phenomenological model and turn out to play an essential role for films of intermediate thickness at the late stage of current decay. The screening due to free vortices is discussed self-consistently in the Debye-Hueckel approximation and is shown to be substantial in the onset region. The theoretical results are compared quantitatively with the experimental data of Ekholm and Hallock (Phys. Rev. B 21, 3902 (1980)) on persistent current decay. The memory effect observed in experiment is interpreted as a consequence of the vortex density relaxation.
Institutional efforts to address disadvantaged students: An “up-so-down” view

Practitioners at individual community colleges and in-state agencies recognize the struggles of disadvantaged students, yet their combined efforts do not overcome the policies and practices that are contrary to advancing and aiding large student populations.
Test–retest stability of calibrated BOLD-fMRI in HIV− and HIV+ subjects

Subject performance, scanner hardware, or biological factors can affect single session neuroimaging measures. Stability studies using calibrated blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-fMRI) have been performed in health but not disease. We utilized calibrated BOLD-fMRI to determine the effects of HIV on neurovascular coupling. Six clinically stable HIV-infected patients (HIV+) and 10 seronegative controls (HIV-) were scanned at two separate sessions approximately 3 months apart. Both mild hypercapnia (5% CO(2)) exposure and a visual functional activation task were performed. Intraclass correlation coefficients (ICC) and inter-subject variance were determined for calibrated BOLD-fMRI measures (baseline cerebral blood flow (CBF), functional CBF, BOLD, and cerebral metabolic rate of oxygen consumption (CMRO(2)) changes) for HIV+ and HIV- subjects. The two groups did not differ in age, sex, or education. HIV+ subjects had lower mean baseline CBF (p<0.04, Cohen's d=-1.07) and functional BOLD responses (p<0.001, Cohen's d=-2.47) and a trend towards a decrease in mean functional CBF responses (p=0.07, Cohen's d=-0.92) despite similar mean functional CMRO(2) changes (p=0.71, Cohen's d=0.19). The stability of each calibrated BOLD-fMRI measure, as assessed by ICC, was significantly lower for HIV+ subjects. In addition, HIV+ participants had greater inter-subject variability for baseline CBF (p<0.02), functional BOLD (p<0.001), CBF (p<0.001), and CMRO(2) (p<0.002) responses. Our results demonstrate that calibrated BOLD-fMRI measures have excellent stability within healthy controls. In contrast, these values have greater variability in clinically stable HIV+ subjects and may reflect alterations in coupling between CBF and CMRO(2) with disease.
Effort flow analysis: a methodology for directed product evolution

Abstract Part count reduction through part combination is a recognized goal of design for assembly (DFA). Some of the many benefits of part count reduction are: a reduced number of assembly operations, reduced procurement costs, cycle time reduction, supply chain reduction, and higher potential profits. In previous work, force flow analysis, a new technique to map forces as they flow across interfaces in a product, was shown to be successful at systematically providing creative insights for part combination. These insights arise by highlighting components having no relative motion between them. This paper presents a novel concept that extends the theoretical basis of force flow analysis to a much broader scope, referred to as effort flow analysis, addressing component combinations having varying degrees of relative motion. A systematic method for classifying these sets of components is given, and compliant mechanisms are presented as an example of successful combinations across interfaces with relative motion. Examples are provided for the redesign of a ‘Quick Grip™ Clamp’ and a staple remover, both of which highlight a specific class of relative motion components.
Video Acuity: A Metric to Quantify the Effective Performance of Video Systems

There is a widely acknowledged need for metrics to quantify the performance of video systems. Existing metrics are either difficult to measure, or are largely theoretical, or do not reflect the full range of effects to which video may be subject, or do not relate easily to performance in real world tasks. We propose a new empirical metric –Video Acuity – that is simple to measure and is likely to relate directly to task performance. Video acuity is determined by the smallest letters that can be automatically identified through the video system. It is expressed most conveniently in letters per degree of visual angle. We provide examples of application of the metric to several video systems.
Minimal Regulators for Rank-2 Subgroups of Rational and $K3$ Elliptic Surfaces

We determine the smallest possible regulator R(P,Q) for a rank-2 subgroup ℤP⊕ℤQ of an elliptic curve E over ℂ(t) of discriminant degree 12n for n = 1 (a rational elliptic surface) and n = 2 (a K3 elliptic surface), exhibiting equations for all (E,P,Q) attaining the minimum. The minimum R(P,Q) = 1/36 for a rational elliptic surface was known [Oguiso and Shioda 91], but a formula for (E,P,Q) was not, nor was the fact that this is the minimum for an elliptic curve of discriminant degree 12 over a function field of any genus. For a K3 surface, both the minimal regulator R(P,Q) = 1/100 and the explicit equations are new. We also prove that 1/100 is the minimum for an elliptic curve of discriminant degree 24 over a function field of any genus. The optimal (E,P,Q) are uniquely characterized by having mP and m′Q integral for m ≤ M and m′ ≤ M′, where (M,M′) = (3, 3) for n = 1 and (M,M′) = (6, 3) for n = 2. In each case MM′ is maximal. We use the connection with integral points to find explicit equations for the cu...
Evaluation of mass spectrometry and radiation detection for the analysis of radionuclides

Radioactive elements are of increasing importance in the areas of human health and safety, the environment, use in terrorism, and nuclear nonproliferation. Accurate and sensitive measurement of fission products, medical isotopes, and actinide species are a vital part of the job entrusted to the national laboratories. Several competing techniques exist. They can be mainly summarized into two categories: radiation and mass spectrometric detection methods. Traditional radiometric counting methods, which are based on the measurement of natural decay of radionuclides, play an important role in the detection of radionuclides. Fission track analysis, which uses thermal neutron induced fission to detect fissionable isotopes, now reaches a limit of detection (LOD) of 10 6 atoms. Of the mass spectrometric detection techniques, inductively coupled plasma mass spectrometry, provides the best sensitivity for the cost in low-level determinations of long-lived radionuclides. Other methods, such as thermal ionization mass spec and accelerator mass spec can provide greater sensitivity in some cases but the cost is higher. Depending on the types of mass analyzers, LOD varies from ng/l to pg/l. More importantly, mass spectrometry is capable of offering precise isotopic ratio information that may act as a fingerprint for identifying the origins of nuclear materials. As the technology matures mass techniques now can provide suitable detection of the shorter-lived isotopes. This criterion is critical as the prompt determination of radionuclides is becoming of overriding importance. This work provides radiometric information displayed in a manner that allows for easy comparison to mass counting. The information can then be used as a general guide to determine the most suitable method to use for the prompt determination of radionuclides.
Reach of Fermilab Tevatron upgrades for SU(5) supergravity models with nonuniversal gaugino masses

We explore the reach of luminosity upgrades of the Fermilab Tevatron collider for $\mathrm{SU}(5)$ supergravity models in which non-universal GUT-scale gaugino masses arise via a vacuum expectation value for the auxiliary component of a superfield that transforms as a 24, 75 or 200 dimensional representation of $\mathrm{SU}(5).$ This results in a different pattern of sparticle masses and mixing angles from what is expected in the minimal supergravity $(\mathrm{MSUGRA})$ model with universal GUT scale gaugino masses. We find that the resulting signal cross sections, and hence the reach of the Tevatron, are sensitive to the gaugino masses at the GUT scale. In the 24 model, the large splitting amongst the two lightest neutralinos leads to SUSY events containing many isolated leptons, including events with a real leptonic Z boson plus jets plus missing energy signal which is visible over much of parameter space. In contrast, in the 75 and 200 models, the reach via leptonic SUSY signals is greatly reduced relative to $\mathrm{MSUGRA},$ and the signal is usually visible only via the canonical ${E}_{T}+\mathrm{jets}$ channel.
Enhancing VR-based visualization with a 2D vibrotactile array

We discuss methods to enable haptic visualization on vibrotactile arrays. Our work is motivated by the potential for a tactile array to provide an additional useful channel for information such as location cues related to dataset features or remote user behaviors. We present a framework for array rendering and several specific techniques. Novel aspects of our work include the example application of a palm-sized tactile array to visualize dataset features or remote user state in a VR system, a generalized haptic glyph mechanism for 2D tactile arrays, and the extension of graphical visualization techniques to haptics (glyphs, fisheye distortion, spatial anti-aliasing, gamma correction).
The price of privately releasing contingency tables and the spectra of random matrices with correlated rows

Marginal (contingency) tables are the method of choice for government agencies releasing statistical summaries of categorical data. In this paper, we derive lower bounds on how much distortion (noise) is necessary in these tables to ensure the privacy of sensitive data. We extend a line of recent work on impossibility results for private data analysis [9, 12, 13, 15] to a natural and important class of functionalities. Consider a database consisting of n rows (one per individual), each row comprising d binary attributes. For any subset of T attributes of size |T|=k, the marginal table for T has 2k entries; each entry counts how many times in the database a particular setting of these attributes occurs. We provide lower bounds for releasing all d k k-attribute marginal tables under several different notions of privacy. (1) We give efficient polynomial time attacks which allow an adversary to reconstruct sensitive information given insufficiently perturbed marginal table releases. In particular, for a constant k, we obtain a tight bound of ~Ω(min √n, √dk-1) on the average distortion per entry for any mechanism that releases all k-attribute marginals while providing "attribute" privacy (a weak notion implied by most privacy definitions). (2) Our reconstruction attacks require a new lower bound on the least singular value of a random matrix with correlated rows. Let M(k) be a matrix with d k rows formed by taking all possible k-way entry-wise products of an underlying set of d random vectors from {0,1}n. For constant k, we show that the least singular value of M(k) is ~Ω(√dk) with high probability (the same asymptotic bound as for independent rows). (3) We obtain stronger lower bounds for marginal tables satisfying differential privacy. We give a lower bound of ~Ω(min {√n, √ dk), which is tight for n ~Ω (dk). We extend our analysis to obtain stronger results for mechanisms that add instance-independent noise and weaker results when k is super-constant.
Potassium currents of acutely isolated adult rat superior cervical ganglion neurons

K+ currents of adult rat superior cervical ganglion neurons were studied using the voltage-clamp technique. Neuronal somata were dissociated from the ganglion using an enzymatic dispersion technique and voltage-clamped using the whole-cell patch-clamp technique. In solutions designed to isolate K+ currents, depolarization from a prepulse potential of −100 mV induced both transient and sustained outward current components. The transient current was completely eliminated by depolarization to −50 mV. The remaining sustained current component could be separated further into Ca2+-sensitive and Ca2+-insensitive components by superfusion with a Ca2+-free external solution. The transient current, which could be isolated by digital substraction, rose rapidly and decayed over the subsequent 80 ms. Reversal potential determinations in different K+-containing solutions demonstrated that the current was carried primarily by K+. The transient current showed voltage-dependent inactivation, showing 50% inactivation near −87 mV and was completely inactivated at potentials more positive than −60 mV. The transient current recovered from inactivation with a voltage-dependent time course, the time course of inactivation decreasing with hyperpolarization. This transient outward current had characteristics of IA. The sustained Ca2+-insensitive outward current showed little decay over 800 ms and was also carried primarily by K+. This current component had characteristics similar to the delayed rectifier. A third sustained outward current eliminated by superfusion with Ca2+-free external solution had characteristics similar to the Ca2+-dependent K+ current.
Tall Fescue Cultivar and Fungal Endophyte Combinations Influence Plant Growth and Root Exudate Composition

Tall fescue (Lolium arundinaceum (Schreb.)) is a cool-season perennial grass used in pastures throughout the Southeastern United States. The grass can harbor a shoot-specific fungal endophyte (Epichloe coenophiala) thought to provide the plant with enhanced resistance to biotic and abiotic stresses. Because alkaloids produced by the common variety of the endophyte cause severe animal health issues, focus has been on replacing the common-toxic strain with novel varieties that do not produce the mammal-toxic alkaloids but maintain abiotic and biotic stress tolerance benefits. Little attention has been given to the influence of the plant-fungal symbiosis on rhizosphere processes. Therefore, our objective was to study the influence of this relationship on plant biomass production and root exudate composition in tall fescue cultivars PDF and 97TF1, which were either not infected with the endophyte (E-), infected with the common toxic endophyte (CTE+) strain or with one of two novel endophytes (AR542E+, AR584E+). Plants were grown sterile for three weeks after which plant biomass, total organic carbon, total phenolic content and detailed chemical composition of root exudates were determined. Plant biomass production and exudate phenolic and organic carbon content were influenced by endophyte status, tall fescue cultivar, and their interaction. GC-TOF MS identified 132 compounds, including lipids, carbohydrates and carboxylic acids. Cluster analysis showed that the interaction between endophyte and cultivar resulted in unique exudate profiles. This is the first detailed study to assess how endophyte infection, notably with novel endophytes, and tall fescue cultivar interact to influence root exudate composition. Our results illustrate that tall fescue cultivar and endophyte status can influence plant growth and root exudate composition, which may help explain the observed influence of this symbiosis on rhizosphere biogeochemical processes.