cssi/SciSciGPT-SciSciNet huggingface dataset:
The universal density of measurement

The notion of measurement plays a central role in human cognition. We measure people’s height, the weight of physical objects, the length of stretches of time, or the size of various collections of individuals. Measurements of height, weight, and the like are commonly thought of as mappings between objects and dense scales, while measurements of collections of individuals, as implemented for instance in counting, are assumed to involve discrete scales. It is also commonly assumed that natural language makes use of both types of scales and subsequently distinguishes between two types of measurements. This paper argues against the latter assumption. It argues that natural language semantics treats all measurements uniformly as mappings from objects (individuals or collections of individuals) to dense scales, hence the Universal Density of Measurement (UDM). If the arguments are successful, there are a variety of consequences for semantics and pragmatics, and more generally for the place of the linguistic system within an overall architecture of cognition.
A software-only scheme for managing heap data on limited local memory(LLM) multicore processors

This article presents a scheme for managing heap data in the local memory present in each core of a limited local memory (LLM) multicore architecture. Although managing heap data semi-automatically with software cache is feasible, it may require modifications of other thread codes. Crossthread modifications are very difficult to code and debug, and will become more complex and challenging as we increase the number of cores. In this article, we propose an intuitive programming interface, which is an automatic and scalable scheme for heap data management. Besides, for embedded applications, where the maximum heap size can be profiled, we propose several optimizations on our heap management to significantly decrease the library overheads. Our experiments on several benchmarks from MiBench executing on the Sony Playstation 3 show that our scheme is natural to use, and if we know the maximum size of heap data, our optimizations can improve application performance by an average of 14p.
Thrombophilias in Pregnancy

Thrombophilic conditions are associated with an increased risk of venous thromboembolic events (VTE) during pregnancy. Thrombophilic disorders are either acquired, as in antiphospholipid syndrome, or inherited, as in factor V Leiden. Both are associated with VTE but acquired disorders can also increase the risk of arterial events. However, there is controversy as to whether they may adversely affect other pregnancy outcomes including pregnancy loss, placental abruption, severe preeclampsia, and stillbirth. This article discusses the effect of thrombophilias on pregnancy.
Simultaneous transmit and sense for cognitive radios using full-duplex: A first study

In two-tier cognitive radio networks, spectrum sensing is important to minimize the interference to the primary users. With half-duplex radios, spectrum sensing has to be performed periodically between transmissions, leading to spectral inefficiencies. In this paper, we study the achievable rate gain and transmission range increase for in-band full-duplex transmissions using directional multi-reconfigurable antennas. The aim is to enable simultaneous transmission and sensing in cognitive radio networks. Our results show that directionality of multi-reconfigurable antennas can increase both the range and rate of full-duplex transmissions over omni-directional antenna based full-duplex transmissions.
Hydrodynamics of the spinal epidural space in pigs: effects of death and exsanguinations.

Background and Objectives: We have investigated how the vascular components of the spine determine the resistance and capacitance of the spinal epidural space and determined the magnitude of the longitudinal pressure gradient in the space during fluid infusion. Methods: Pigs were studied during isoflurane anesthesia. Tuohy needles were inserted into midthoracic spine at adjacent interspaces, one to measure pressure in the epidural space and one for fluid infusion. A third Tuohy needle was inserted in the lumbar epidural space. Fluid was infused at a constant flow (0.9-3.1 mL/min) until epidural space pressure reached a steady plateau, then the pump was shut off, and pressure returned to baseline over 5 to 6 mins. Resistance was calculated as the ratio of plateau pressure and flow. Initial (first 20-30 secs) and late (1-5 mins) capacitance was calculated. Measurements were made with the animal alive, 15 mins after its life was terminated by an intravenous injection of KCl, and then after exsanguination. Results: During fluid infusion, the pressure gradient between the lumbar and thoracic epidural space was small, on the order of 1 to 2 mm Hg. Death reduced resistance but not capacitance, whereas exsanguination reduced late capacitance but not resistance. Neither maneuver affected initial capacitance. Conclusions: There is a small longitudinal pressure gradient within the epidural space during fluid infusion. Hence, the major source of resistance occurs where fluid leaves the epidural space. Death reduced resistance, perhaps by depressurizing spinal arteries in the intervertebral foramina, but did not affect capacitance. Blood in epidural veins is a major determinant of late epidural capacitance.
A comparison of closed-form and finite-element solutions of thick laminated anisotropic rectangular plates

Abstract In this study the effects of reduced integration, mesh size, and element type (i.e. linear or quadratic) on the accuracy of a penalty-finite element based on the theory governing thick, laminated, anisotropic composite plates are investigated. In order to assess the accuracy of the present finite element, exact closed-form solutions are developed for cross-ply and antisymmetric angle-ply rectangular plates simply supported and subjected to sinusoidally distributed mechanical and/or thermal loadings, and free vibration.
Radar signatures of a vertical-axis wind turbine

The interference from wind farms on radar systems is a topic of current interest in the radar community. Significant efforts have gone into the assessment and mitigation of wind turbine induced clutter. In particular, the radar signatures of horizontal-axis wind turbines have been well studied based on electromagnetic simulations and measurements. Recently, the US Department of Energy is considering vertical-axis wind turbines (VAWT) as a candidate for offshore wind power generation (Sandia National Laboratories, Sandia Labs News Releases, Jul. 30, 2012 [Online]). Some of the potential advantages of VAWT over its horizontal-axis counterpart include better scalability to large sizes and mechanical simplicity for service and maintenance. From the radar perspective, it is important to evaluate how the radar signatures of a VAWT differ from those of the traditional three-blade horizontal-axis turbine.
ULTRASTRUCTURAL STUDIES OF VASOPRESSIN EFFECT ON ISOLATED PERFUSED RENAL COLLECTING TUBULES OF THE RABBIT

Isolated cortical collecting tubules from rabbit kidney were studied during perfusion with solutions made either isotonic or hypotonic to the external bathing medium. Examination of living tubules revealed a reversible increase in thickness of the cellular layer, prominence of lateral cell membranes, and formation of intracellular vacuoles during periods of vasopressin-induced osmotic water transport. Examination in the electron microscope revealed that vasopressin induced no changes in cell structure in collecting tubules in the absence of an osmotic difference and significant bulk water flow across the tubule wall. In contrast, tubules fixed during vasopressin-induced periods of high osmotic water transport showed prominent dilatation of lateral intercellular spaces, bulging of apical cell membranes into the tubular lumen, and formation of intracellular vacuoles. It is concluded that the ultrastructural changes are secondary to transepithelial bulk water flow and not to a direct effect of vasopressin on the cells, and that vasopressin induces osmotic flow by increasing water permeability of the luminal cell membrane. The lateral intercellular spaces may be part of the pathway for osmotically induced transepithelial bulk water flow.
Noncatalytic Alcoholysis Kinetics of Soybean Oil

Reaction kinetics for the alcoholysis of soybean oil with methanol, ethanol, and isopropanol were evaluated in the absence of catalyst. Metal reactor surfaces catalyzed these reactions, so the reactions were conducted in glass capillary tubes at 120, 150, and 180°C. The reactivity of the alcohols increased with decreasing carbon number. Higher temperatures promoted faster reactions. Higher alcohol stoichiometries did not significantly increase reaction rates; this was attributed to the limited solubility of the alcohol in the soybean oil. At less than 20% conversion, the solubility of the alcohol in the oil phase continuously increased, resulting in increased reaction rates. At approximately 20% conversion, the reaction systems became homogeneous until a glycerine phase was formed at high conversions. In addition to their fundamental value, these data provided a basis on which catalytic reactions can be investigated between 100 and 200°C.
From "magic bullet" to "specially engineered shotgun loads": the new genetics and the need for individualized pharmacotherapy.

Steady progress in the identification of human pharmacogenetic variants and new discoveries of disease susceptibility genes makes the old notion of one disease/one drug untenable. Advances in the ability to rapidly identify these variants, when coupled with appropriate drug delivery systems, should revolutionize pharmacotherapy. BioEssays20:683–685, 1998.© 1998 John Wiley & Sons Inc.
Respiratory neural activity during long-term facilitation

Intermittent hypoxia results in a long-term facilitation (LTF) of respiratory efferent activity. The studies reviewed here presented data from both anesthetized and decerebrate, paralyzed, vagotomized, artificially ventilated adult cats. Multiple arrays of tungsten microelectrodes were used to record the concurrent responses of brain stem neurons that contribute to respiratory motor pattern generation. Spike trains were analyzed with firing rate histograms, peristimulus time histograms, cycle triggered histograms, spike triggered averages with multiunit phrenic efferent activity, cross correlation histograms, joint peristimulus time histograms and the gravity method. These studies addressed several hypotheses. (1) There is parallel processing of input from carotid chemoreceptors to the brain stem. (2) Respiratory related midline neurons are involved in the induction and maintenance of LTF. (3) There is a change in effective connectivity of brain stem neurons with LTF. (4) Neural networks involved in the induction and maintenance of LTF have patterns of synchrony that recur with a frequency greater than expected by chance.
Improved SFE recovery of trace analytes from liver using an integral micrometering valve–SPE column holder assembly

A novel integral restrictor–collector has been designed for use with a conventional supercritical fluid extraction (SFE) apparatus. The assembly reduces the path length between a micrometering valve and collector (a solid phase extraction (SPE) column), obviating the need for the complicated tubing and connectors usually associated with such devices. Also described is a heating-block assembly which encases the micrometering valve and provides uniform heating of the valve during extraction. The valve–SPE column assembly was part of a system used to perform the first reported SFE multi-residue drug recovery from fortified liver. Extractions used carbon dioxide pressurized to 690 bar as the supercritical fluid. Flow rates of expanded gas through the SPE columns were 3–4 L/min with concomitant quantitative trapping of the analytes on the sorbent bed. After SFE the three nitrobenzamide antimicrobial drug residues from the liver were eluted from the SPE columns by off-line analysis. The results demonstrated that losses of trace level analytes in tissue may be significantly reduced by including an integral metering valve-collector assembly as part of the SFE apparatus.
Mechanistic role of NS4A and substrate in the activation of HCV NS3 protease

Hepatitis C virus (HCV) NS3 protease is the key enzyme for its maturation. Three hypotheses have been advanced in the literature to demonstrate the mechanism of the activation of the HCV NS3 protease. A virus-encoded protein NS4A and substrate are proposed to be involved in the activation of the HCV NS3 protease. However, the three hypotheses are not completely consistent with one another. Multiple molecular dynamics simulations were performed on various NS3 protease systems: free NS3 protease, NS3/4A, NS3/inhibitor, and NS3/4A/inhibitor complexes, to further unravel the mechanism of the activation of the NS3 protease. Simulation results suggest that the binding of NS4A induces a classic serine protease conformation of the catalytic triad of the NS3 protease. NS4A rearranges the secondary structure of both the N-terminus and catalytic site of the NS3 protease, reduces the mobility of the global structure of the NS3 protease, especially the catalytic site, and provides a rigid and tight structure, except for the S1 pocket, for the binding and hydrolysis of substrates. The binding of substrate also contributes to the activation of the NS3 protease by an induced-fit of the classic serine protease catalytic triad. However, the global structure of the NS3 protease is still loose and highly flexible without stable secondary structural elements, such as helix α0 at the N-terminus and helix α1 and β-sheet E1-F1 at the catalytic site. The structure of the NS3 protease without NS4A is not suitable for the binding and hydrolysis of substrates.
Hypocalcemic rickets: an unusual cause of dilated cardiomyopathy

We report a breast-fed infant with clinical evidence of rickets and with dilated cardiomyopathy who responded well to supplemental calcium and vitamin D. We believe that this is the first report of such an association in an American child.
On the buckling of stiffened imperfect cylindrical shells

A theoretical investigation of the buckling behavior of imperfect ring and stringer stiffened shells under axial compression was carried out. The nonlinear Donnell-type equations for imperfect shells with "smeared out" ring and stringer stiffeners have been reduced to an equivalent set of nonlinear ordinary differential equations. The resulting two-point boundary value problem was solved numerically by the "shooting method." The use of this method made it possible to investigate how the axial load level at the limit point is affected by the following factors: the prebuckling growth caused by the edge constraint, different sets of boundary conditions, the orientation and shape of the axisymmetric and asymmetric imperfection components and the eccentricity in the load application. As a result of this investigation, a simple formula is proposed which makes it possible to take into account both the effect of initial imperfections and the effect of the appropriate boundary conditions.
Organization of the neurons in the anterior division of the anteroventral cochlear nucleus of the cat. Light-microscopic observations

Abstract The anterior division of the anteroventral cochlear nucleus of the cat was studied in the light microscope. Criteria were developed to distinguish neurons in the Nissl-stained anteroventral cochlear nucleus which could then be correlated with those types found in Golgi preparations. Based on the patterns of distribution of the neuronal types, their size and shape, and the number of primary dendrites, the bushy cells (Golgi) are shown to correspond to the spherical cells (Nissl), whereas the stellate and small cells (Golgi) correspond to the ovoid cells (Nissl). The present results provide a background for a detailed study of the synaptic organization of the different cell types of the anterior division with the electron microscope and electrophysiological methods.
A general solution in partial orders for the Camin-Sokal model in phylogeny

Abstract In 1965 a criterion was described for choosing from among a large number of evolutionary hypotheses a group of those considered to be most likely (Camin & Sokal, 1965) . A method for finding all the evolutionary hypotheses which satisfied this criterion was not known at that time and this has continued to be a problem. Here a solution to this problem is presented. The theory of partial orders is used to analyze a slightly more general problem than was originally posed in 1965.
Research note: a lack of response to pantothenic acid supplementation to a corn and soybean meal broiler diet.

Abstract Two 21-day battery studies were conducted to determine whether a corn and soybean meal diet without pantothenic acid supplementation was adequate for growth and feed efficiency of broilers. In each experiment, 641-day-old broiler chicks (32 male and 32 female) were assigned to each of six dietary treatments. The basal diet was supplemented with 0, .3, .6, 2.4, 4.8, and 14.4 mg of supplemental pantothenic acid/kg of diet. Each diet in both experiments was fed to eight pens containing four females and four male day-old Arbor Acres broiler chicks. The basal diet contained 22.3% protein and 4.74 mg/kg pantothenic acid by analysis. No improvement in growth or feed efficiency was obtained from any level of pantothenic acid supplementation.
Evidence for simultaneous abiotic-biotic oxidations in a microbial-Fenton's system

The conditions that support the simultaneous activity of hydroxyl radicals (OH.) and heterotrophic aerobic bacterial metabolism were investigated using two probe compounds: (1) tetrachloroethene (PCE) for the detection of OH. generated by an iron-nitrilotriacetic acid (Fe-NTA) catalyzed Fenton-like reaction and (2) oxalate (OA) for the detection of heterotrophic metabolism of Xanthobacter flavus. In the absence of the bacterium in the quasi-steady-state Fenton's system, only PCE oxidation was observed; conversely, only OA assimilation was found in non-Fenton's systems containing X. flavus. In combined Fenton's-microbial systems, loss of both probes was observed. PCE oxidation increased and heterotrophic assimilation of OA declined as a function of an increase in the quasi-steady-state H2O2 concentration. Central composite rotatable experimental designs were used to determine the conditions that provide maximum simultaneous abiotic-biotic oxidations, which were achieved with a biomass level of 10(9) CFU/mL, 4.5 mM H2O2, and 2.5 mM Fe-NTA. These results demonstrate that heterotrophic bacterial metabolism can occur in the presence of hydroxyl radicals. Such simultaneous abiotic-biotic oxidations may exist when H2O2 is injected into the subsurface as a microbial oxygen source or as a source of chemical oxidants. In addition, hybrid abiotic-biotic systems could be used for the treatment of waters containing biorefractory organic contaminants present in recycle water, cooling water, or industrial waste streams.
Nanochannel-based electrochemical sensor for the detection of pharmaceutical contaminants in water.

Effective real-time monitoring is the key to understanding and tackling the issue of pharmaceutical contamination of water. This research demonstrates the utility of an alumina nanochannel-based electrochemical sensor platform for the detection of ibuprofen in water derived from various sources. Our results indicate that the sensor is highly sensitive with a limit of detection at 0.25 pg mL−1. The novel sensor described here has potential for application as a simple, rapid, inexpensive and highly reliable method for real-time environmental water quality assessment.
Metabolic jet lag when the fat clock is out of sync.

There is a growing appreciation of the importance of circadian regulation in energy homeostasis, and the dysregulation of the circadian clock has been associated with obesity and metabolic abnormalities. A new study shows that adipocyte-specific deletion of a core circadian clock gene, Arntl (Bmal1), in mice shifts the timing of their feeding behavior, resulting in obesity (pages 1768–1777).
Multifunctional acrylate monomers, dimers and oligomers: Applications from contact lenses to wood‐polymer composites

The synthesis of various esters of α-hydroxymethylacrylate are summarized along with a brief description of their properties and polymerizability. Polymer characterization is given, including thermal behavior, solubility and spectroscopic properties. Derivatives of the acrylates are generated through reaction of the alcohol group to give halides, esters, ethers, and ether dimers. The last, along with additional multifunctional acrylates generated through the chemistry inherent in the synthetic approach, allow formation of a number of cyclopolymers, Michael polyadducts, and crosslinked systems.
A content analysis of local television news in a top 50 market

The researchers developed a quantitative content analysis of three network television stations' local news. The four criteria developed from the review of literature were: (1) local news; (2) objectivity; (3) ambition; and (4) production. Results from three reviewers' judgments were that relatively high scores were found for local news, objectivity, and production. However, ambition scores were relatively low for all three stations. The researchers made suggestions for further studies in other locales.
Best Linear Unbiased Prediction of Breeding Values Not in the Model for Records

Abstract Methods for computing best linear unbiased predictions of random variables (breeding values or sire values) not appearing in the model for records are presented. One method involves taking linear functions of best linear unbiased predictions of variables appearing in the model for records. The second method involves expanding the usual mixed model equations to include variables not in the model.
Emotionality, Emotion Regulation, and School Performance in Middle School Children.

Abstract This research investigated the connections of middle school students' emotional dispositions and academic-related affect with their school performance. One hundred three 6th–8th grade students completed three self-rated assessments regarding: (a) their academic competency; (b) affective tendencies (both mood and emotion regulation); and (c) negative emotions experienced during school-related tasks. Teachers assessed students' positive and negative moods, and schools provided achievement test results and student grades as measures of cognitive ability/achievement and school performance, respectively. Results indicated that although students' emotion regulation, general affective dispositions, and academic affect were related to each other, each of these variables also made a unique significant contribution to students' GPA, over and above the influence of other cognitive contributors. Overall, these results provide support for the role of socio-emotional factors in students' school performance, while also clarifying some of the uniquely affective contributors (rather than relationships or goals) to that performance.
Blunt Cardiac Trauma: Atrioventricular Valve Disruption and Ventricular Septal Defect

Nonpenetrating cardiac trauma resulting in cardiac chamber or valvar rupture is uncommon, requiring a high degree of suspicion for diagnosis. A case involving avulsion of the tricuspid and mitral papillary muscles with resultant interventricular septal rupture is reported. This case illustrates the importance of transesophageal echocardiography in the rapid diagnosis of blunt cardiac trauma. Surgical treatment of this condition is also discussed.
Markets for public goods

There is a presumption in some circles that the identification of an externality or a public good presents a prima facie case for government intervention. Tyler Cowen has assembled a group of articles that challenge this view by arguing that the market, broadly construed, can handle many problems of public goods and externalities that are normally considered the province of the state. Although these articles present a stimulating perspective on problems of externalities and public goods, several of the essays overstate their case and misrepresent the standard theory of public goods and externalities.
Comparison of Scores for Intellectually Gifted Students on the WISC-R and the Fourth Edition of the Stanford-Binet.

The WISC-R and the Fourth Edition of the Stanford-Binet (SB: FE) were compared in the identification and assessment of 48 intellectually gifted students in the primary and secondary grades. While only a 3.2-point difference between the mean SB: FE Composite score and the mean WISC-R Full Scale score was found, (r = .393, p. ⩽ .01), the t test between the two scores was significant (t = 2.30, p ⩽ .05). Correlations between the three scales of the WISC-R and the SB: FE four broad area and Composite scores ranged from −.219 (SB: FE Abstract/Visual Reasoning with WISC-R Verbal) to .599 (SB: FE Short-Term Memory with WISC-R Full Scale). Within the correlational matrix, only 5 of the 15 correlations were significant. Both the SB: FE Abstract/Visual Reasoning and Quantitative Reasoning Area scores had no significant correlations with any of the WISC-R scores.
COMPARATIVE SEED SHADOWS OF BIRD-, MONKEY-, AND WIND-DISPERSED TREES

Although spatial patterns of seed distribution are thought to vary greatly among plant species dispersed by different vectors, few studies have directly examined this assumption. We compared patterns of seed rain of nine species of trees disseminated by large birds, monkeys, and wind in a closed canopy forest in Cameroon. We used maximum-likelihood methods to fit seed rain data to four dispersal functions: inverse power, negative exponential, Gaussian, and Student t. We then tested for differences in dispersal characteristics (1) among individuals within species, and (2) among species dispersed by the same vector. In general, an inverse power function best described animal-dispersed species and the Gaussian and Student t functions best described wind-dispersed species. Animal-dispersed species had longer mean dispersal distances than wind-dispersed species, but lower fecundities. In addition to these distinct differences in average dispersal distance and functional form of the seed shadow between animal- and wind-dispersed species, seed shadows varied markedly within species and vector, with conspecifics and species within vector varying in their dispersal scale, fecundity, and clumping parameters. Dispersal vectors determine a significant amount of variation in seed distribution, but much variation remains to be explained. Finally, we demonstrate that most seeds, regardless of vector, fall directly under the parent canopy. Long-distance dispersal events (>60 m) account for a small proportion of the seed crop but may still be important in terms of the absolute numbers of dispersed seeds and effects on population and community dynamics.
15-Year experience in the treatment of rectal prolapse in children.

Abstract Background Rectal prolapse is a common and usually self-limited condition in children. Several surgical techniques have been advocated for refractory prolapse. We reviewed our experience with treatment and the outcome of refractory rectal prolapse. Methods Retrospective review was conducted on patients undergoing surgery for rectal prolapse from January 1993 to March 2009. Patients with imperforate anus/cloacal abnormalities, Hirschsprung disease, spina bifida, or prior pull-through were excluded. Results Twenty patients underwent 23 procedures for rectal prolapse. There were 10 posterior sagittal rectopexies, 6 transabdominal rectopexies, 5 laparoscopic rectopexies, 1 hypertonic saline injection, and 1 anal cerclage. The mean duration of symptoms was 1.6 years (range, 1-10 years). The mean age at operation was 6.8 years (range, 4 months-19 years), with a 5:1 male predominance. There was no operative or perioperative mortality. Median length of follow-up was 7.2 months; 2 patients were lost to follow-up. The overall recurrence rate was 35%. All recurrences followed posterior sagittal rectopexies, which had a 70% recurrence rate. Four patients required reoperation, all done transabdominally (2 open and 2 laparoscopically). None of the 3 remaining patients with mild recurrences required reoperation. Conclusions A variety of options for management of refractory rectal prolapse in children exist. Laparoscopic rectopexy seems to be safe and a comparatively successful option in these children.
Ovulation resumption after medical abortion with mifepristone and misoprostol

Abstract Background As an antiprogestin, mifepristone may have an impact on the return to ovulation in a manner that is not only attributable to its abortifacient activity. Our aim was to measure the time-to-ovulation in women who received mifepristone 200 mg orally and misoprostol 800 mcg vaginally for abortion up to 63 days of gestation. Study Design This planned substudy was part of a multicenter randomized trial of mifepristone 200 mg followed immediately or 24 h later by misoprostol 800 mcg vaginally. Women who had successful expulsion of the gestational sac based on ultrasound examination 1 week after mifepristone treatment were enrolled. All subjects used nonhormonal contraception until study completion. Baseline serum progesterone (P) levels were drawn on day 8±1 after mifepristone administration and then twice weekly until the P level was >3 ng/mL, consistent with ovulation. The mean time-to-ovulation was calculated using interval censored regression to address the censoring due to participant discontinuation. Results Fourteen (52%) of 27 enrolled women completed the substudy. The longest period of time that a subject who did not complete the study was followed was 29 days. Ovulation occurred 20.6±5.1 (range 8–36) days after mifepristone administration. Time-to-ovulation was not affected by participant age, gestational age, study arm, body mass index or presence or absence of human chorionic gonadotropin. Conclusions Return to ovulation following medical abortion with mifepristone and misoprostol occurs on average 3 weeks postabortion. Mifepristone 200 mg does not appear to have a lasting effect on ovarian function. Our results should be contextualized by the small sample size, although this is one of the larger studies on return to ovulation after abortion.
Structural requirements and reaction pathways in dimethyl ether combustion catalyzed by supported Pt clusters.

The identity and reversibility of the elementary steps required for catalytic combustion of dimethyl ether (DME) on Pt clusters were determined by combining isotopic and kinetic analyses with density functional theory estimates of reaction energies and activation barriers to probe the lowest energy paths. Reaction rates are limited by C−H bond activation in DME molecules adsorbed on surfaces of Pt clusters containing chemisorbed oxygen atoms at near-saturation coverages. Reaction energies and activation barriers for C−H bond activation in DME to form methoxymethyl and hydroxyl surface intermediates show that this step is more favorable than the activation of C−O bonds to form two methoxides, consistent with measured rates and kinetic isotope effects. This kinetic preference is driven by the greater stability of the CH3OCH2* and OH* intermediates relative to chemisorbed methoxides. Experimental activation barriers on Pt clusters agree with density functional theory (DFT)-derived barriers on oxygen-covered ...
Magnetic-field-aligned characteristics of plasma bubbles in the nighttime equatorial ionosphere

Abstract Measurements of both incoherent-scatter (IS) and backscatter from field-aligned irregularities (FAI) were made in 1978 with ALTAIR, a fully-steerable high-power radar, to investigate the magnetic-field-aligned characteristics of equatorial plasma bubbles. By operating the radar in a latitude-scan IS mode, we were able to map the location and percentage depletion of plasma bubbles as a function of altitude and latitude. By showing that backscatter from FAI is spatially collocated with the upper wall of plasma bubbles, we were able to use the spatial displacement of a field aligned backscatter region to estimate the upward bubble velocity. Besides showing that plasma bubbles are indeed aligned along magnetic field lines, we use this data set to show that a plasma bubble with a percentage depletion of as much as 90% does not have as large an upward velocity as predicted by two-dimensional models. Instead, the inferred bubble velocity is shown to be in better agreement with the bubble velocity predicted by theoretical models using flux-tube-integrated values of electron density and Pedersen conductivity. The need to use flux-tube-integrated values when comparing theory and observation is further stressed by the presence of a non-uniform latitudinal distribution of electron density (i.e. the equatorial anomaly) that was found in the latitude-scan data.
Gill parasites of mummichogs, Fundulus heteroclitus (Teleostei : Cyprinodontidae) : Effects of season, locality, and host sex and size

I investigated the prevalences and densities of gill parasites in 4 seasonal samples of mummichog, Fundulus heter- oclitus (n = 242), from 2 creeks differing in salinity in central Chesapeake Bay. The parasites (and overall prevalence ranges) were: mobile (12-88%) and sessile (0-50%) peritrichs (Ciliophora); Myxobolus funduli (58-94%) (Myxozoa); Gyrodactylidae (0-94%) (includes Gyrodactylus sp. and Fundulotrema sp.) and Salsuginus sp. (74-100%) (Monogenea); metacercariae of Phag- icola diminuta (75-100%) and Echinochasmus schwartzi (79-100%) (Digenea); Ergasilus manicatus (25-100%) (Copepoda); Lironeca ovalis (0-11%) (Isopoda); and cysts of unknown etiology, or CUEs (64-94%) (unknown taxon). CUEs were more abundant in fall and gyrodactylids in winter. The myxozoan, copepod, and 1 species of digenean were most abundant in spring. Except for gyrodactylids and CUEs, densities were greater in the less saline creek for all taxa. There were no significant differences between sexes except in 1 sample; digenean densities increased with host length for females but not males. There was a strong positive relationship of CUE density with host length and weaker positive associations of gyrodactylid and Salsuginus sp. densities with host length. There is increasing interest among ecologists in identifying factors that shape patterns of parasite distributions among hosts. For example, differences in parasite prevalence or density have been related to season (Hanek and Fernando, 1978a, 1978b; Rohde, 1979), features of the host's habitat (Rohde, 1979; Jan- ovy and Hardin, 1987), and host size and sometimes host sex (Burnett-Herkes, 1974; Cloutman, 1975). In this study, I as- sessed the importance of environmental and host factors in de- termining gill parasite densities in mummichogs (Fundulus het- eroclitus) from 2 Chesapeake Bay creeks. Mummichogs inhabit marshes and tidal creeks from Nova Scotia to northern Florida (Hildebrand and Schroeder, 1928) and are abundant in Chesapeake Bay from freshwater to salt water (Weisberg, 1986). Knowledge of the gill parasites of F. heteroclitus is limited primarily to isolated accounts of single parasite species (Kudo, 1918, 1919; Wilson, 1932; Bere, 1936; Mueller, 1937; Bond, 1937, 1938; Hargis, 1955; Stunkard and Uzmann, 1955; Lawler, 1967; Heard, 1970; Roberts, 1970; Rawson, 1973; Billeter, 1974; Murith and Beverly-Burton, 1985) and 2 broad studies on the metazoan parasites of F. het-
Capacities of Hospitalized, Medically Ill Patients to Consent to Treatment

This study was designed to compare the abilities of hospitalized, medically ill patients with non-ill comparison subjects to engage in an informed consent process. Eighty-two inpatients under the age of 70 were recruited from patients admitted for evaluation or treatment of ischemic heart disease (N = 675). The comparison subjects (n = 82) were matched person-to-person on age, gender, race, educational level, and occupation and did not have histories of ischemic heart disease. The hospitalized subjects did not differ from the non-ill comparison subjects on three instruments developed to assess abilities related to decision-making competence. Demographic and mental state variables did not correlate with performance, except for verbal cognitive functioning. There is no reason to believe that hospitalized patients similar to this sample--even if being treated for potentially life-threatening conditions--are at increased risk of inability to engage in a meaningful informed consent process.
A biochemical specific locus mutation system in mice

Two mouse strains DBA/2J and C57BL/6J are heteromorphic with respect to the electrophoretic mobility of at least 8 enzymes and the beta-hemoglobin chain. The genotype of DBA/2J for these markers is: Es-1, Es-3, Gpd-1, Gpi-1, Id-1, Mod-1, Pmg-1, Dip-1 and Hbb; and of C57B1/6J: Es-1, Es-3, Gpd-1, Gpi-1, Id-1, Mod-1, Pgm-1, Dip-1 and Hbb. Electrophoresis on tissues of interstrain hybrids will show the two parental bands and additional hybrid bands if the enzyme is a polymeric structure. In specific locus mutations which result in loss of activity (deletions, nonsense mutations), the hybrid resembles the non-mutated parent. In the mutation results in a change in electrophoretic mobility, some of the bands on the gel will either run faster or slower compared to the hybrid bands in a normal F1 animal. Fifty DBA/2J males were irradiated with gamma-rays from a Co60 source with two doses of 500 R at 24-h intervals at a dose rate of 95 R/min. After this irradiation the males were sterile for approximately 3 months. After the males regained their fertility, they were continuously mated to C57BL/6 females. Thus far somewhat over 2600 animals have been tested and four new mutations detected, giving a frequency of approximately 1.7 X 10(-4) mutations per locus per generation. The four mutations are: two independent mutations at Hbb, one at Mod-1 and one at Id-1.
The mouse p (pink-eyed dilution) and human P genes, oculocutaneous albinism type 2 (OCA2), and melanosomal pH.

Recessive mutations of the mouse p (pink-eyed dilution) gene lead to hypopigmentation of the eyes, skin, and fur. Mice lacking a functional p protein have pink eyes and light gray fur (if non-agouti) or cream-colored fur (if agouti). The human orthologue is the P protein. Humans lacking a functional P protein have oculocutaneous albinism type 2 (OCA2). Melanocytes from p-deficient mice or OCA2 individuals contain small, minimally pigmented melanosomes. The mouse and human proteins are predicted to have 12 membrane spanning domains and possess significant sequence homology to a number of membrane transport proteins, some of which are involved in the transport of anions. The p protein has been localized to the melanosome membrane. Recently, it has been shown that melanosomes from p protein-deficient melanocytes have an abnormal pH. Melanosomes in cultured melanocytes derived from wild-type mice are typically acidic, whereas melanosomes from p protein-deficient mice are non-acidic. Melanosomes and related endosome-derived organelles (i.e., lysosomes) are thought to have an adenosine triphosphate (ATP)-driven proton pump that helps to generate an acidic lumen. To compensate for the charge of these protons, anions must also be transported to the lumen of the melanosome. In light of these observations, a model of p protein function is presented in which the p protein, together with the ATP-driven proton pump, regulates the pH of the melanosome.
Modelling photoelectron effects in X-ray Lithography

The study of photoelectron effects in X-ray Lithography motivates the need for modelling codes to simulate these effects to have an estimate of the influence of x-ray generated photoelectrons in the exposure of resists. We have performed a series of Monte Carlo simulations to study the spatial distribution of photoelectrons in a resist, PMMA, and parametrized this distribution with a set of energy-dependent gaussians for monochromatic X-rays within an energy range of 0.5 KeV to 2.5 KeV. We discuss the effects of the the redistribution of the photoelectron kinetic energy as a function of the electrons generated by the x-ray absorption in various atomic species.
The ferromagnetic-antiferromagnetic properties of copper-manganese and silver-manganese alloys

Abstract Magnetic hysteresis loops displaced from their symmetrical positions about the origin are observed when the alloys of about 5–30 per cent Mn in Cu and 10–25 per cent Mn in Ag are cooled to 1.8°K in a magnetic field. The two remanent magnetizations from each loop are equal both in magnitude and direction and represent a ferromagnetic alignment of a significant fraction of the Mn atomic moments. For each alloy, the hysteresis loop displacement decreases with increasing temperature and its disappearance is attended by large hysteresis losses. At a somewhat higher temperature, the losses vanish and the magnetic susceptibility reaches a maximum. However, the only anomaly in the electrical resistivity vs. temperature curve, indicative of a magnetic transition, occurs at a still higher temperature. All these properties and their dependence on alloy composition are shown to be qualitatively consistent with a microscopic exchange anisotropy model. According to this model, the coexistence of antiferromagnetic and ferromagnetic interactions between Mn atoms of different separation, together with the statistical fluctuations in the local Mn concentration, gives rise to unusual magnetic states in these atomically-disordered alloys.
Affiliation of large numbers of fibroblasts with larval muscle fibers

Abstract Muscle fibers from fourth and fifth instar caterpillars were examined with scanning and thin section electron microscopy. Scanning micrographs showed that early fifth instar specimens had a population of cells lying beneath the basal lamina over the surface of the muscle fiber and in conjunction with tracheoles and nerves. At least two cell types were present. One type could be categorized as tracheoblasts by their close association with the tracheoles and the presence of taenidia within the tracheoblast cytoplasm in sectioned material. A second cell type, characterized by long filamentous processes, contained extensive rough endoplasmic reticulum and cisternae swollen with an electron-dense substance similar in appearance to the basal lamina. This ultrastructural appearance is characteristic of vertebrate fibroblasts and certain types of insect hemocytes. Early and late fourth instar specimens had few cells on their muscle fiber surfaces. Measurements of the basal lamina thickness were taken from thin sections of non-digested muscle fibers of early fourth, late fourth, and early fifth instar animals. The results showed that the basal lamina underwent a large increase in thickness between the fourth and fifth instars. The proliferation of cells which appeared to be in an actively synthesizing state paralleled the increase in basal lamina thickness. This suggests the hypothesis that these cells are active in connective tissue formation, and contribute to the formation of the basal lamina that lies over both them and the muscle fiber.
Theory of transient creep in the L12 intermetallic compounds displaying the yield strength anomaly

Abstract A theory of transient creep in the L1 2 intermetallic alloys displaying the yield strength anomaly is presented. The theory is based on the hypothesis that the mobile a 〈101〉 superdislocations undergo a pinning-depinning transition, displaying critical behavior at a critical stress. The areal-velocity scaling function, which describes the average, time-dependent velocity profile of a dislocation as it propagates through the crystal, is introduced. The theory is compared with preliminary experiments. It is argued that the measurement of transient creep allows one to determine information concerning the deformation history of the sample.
Revisiting the Relationship Between Social Work and Law Enforcement

ABSTRACT Increasingly, law enforcement officers are becoming involved in community roles that require knowledge and sensitivity to social problems beyond their normal training. Social workers can be involved in the training, education, and resource development necessary to prevent incarceration and the escalation of mental health problems officers encounter, especially in the wake of recent terrorist events. Innovative team efforts in the community are elaborated as a product of the inclusion of social work courses in the Administration of Justice major, where officers are instructed in collaborative responses to community crises.
Mathematical programming-based perturbation analysis for GI/G/1 queues

This paper addresses several issues of using the mathematical programming representations of discrete-event dynamic systems in perturbation analysis. In particular, linear programming techniques are used to perform Infinitesimal Perturbation Analysis (IPA) on GI/G/1 queues. A condition for unbiasedness is derived. For finite perturbation analysis (FPA), an upper bound is given for the error term of FPA.
Strain Variation in Hematological Response of Broilers to Dietary Aflatoxin

Abstract The response of clinical blood values to graded levels of dietary aflatoxin was studied in three populations of chickens. Male chicks of two commercial broiler strains, one color-sexed and the other feather-sexed, and a randombred strain were fed dietary aflatoxin at levels of 0, 1.25, 2.50 or 5.0 μg/g of diet from 1 to 21 days of age. At the conclusion of the 21-day treatment period, all remaining birds were bled by cardiac puncture and packed cell volume (PCV), erythrocyte counts (RBC), hemoglobin concentration (Hb), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), total plasma protein, and total plasma cholesterol were determined. All strains of broilers were susceptible to aflatoxicosis as detected by total plasma protein and cholesterol. Anemia associated with aflatoxicosis was induced in the two commercial broiler lines, but not in the randombred line. The PCV, RBC, and Hb were diminished from control values in a dose-related fashion by graded levels of aflatoxin in the commercial broilers, but not in the randombred line. Decreases in MCV with no significant changes in MCHC were observed in all strains.
Alkyl ammonium cation stabilized biocidal polyiodides with adaptable high density and low pressure

The effective application of biocidal species requires building the active moiety into a molecular back bone that can be delivered and decomposed on demand under conditions of low pressure and prolonged high-temperature detonation. The goal is to destroy storage facilities and their contents while utilizing the biocidal products arising from the released energy to destroy any remaining harmful airborne agents. Decomposition of carefully selected iodine-rich compounds can produce large amounts of the very active biocides, hydroiodic acid (HI) and iodine (I2). Polyiodide anions, namely, I3(-), I5(-), which are excellent sources of such biocides, can be stabilized through interactions with large, symmetric cations, such as alkyl ammonium salts. We have designed and synthesized suitable compounds of adaptable high density up to 3.33 g cm(-3) that are low-pressure polyiodides with various alkyl ammonium cations, deliverable iodine contents of which range between 58.0-90.9%.
PKA, Rap1, ERK1/2, and p90RSK mediate PGE2 and EP4 signaling in neonatal ventricular myocytes

We have previously reported that 1) inhibition of cyclooxygenase-2 and PGE2 production reduces hypertrophy after myocardial infarction in mice and 2) PGE2 acting through its EP4 receptor causes hyp...