cssi/SciSciGPT-SciSciNet huggingface dataset:
5 – Catalytic Hydrogenation

Publisher Summary The technique of catalytic hydrogenation can be applied almost universally to unsaturated systems. By appropriate selection of catalyst, pressure, and temperature, a remarkable variety of substrates can be made to undergo hydrogenation, many of them under hydrogen pressure not exceeding 50 psi. A recent development in the technique of hydrogenation has been the use of homogeneous catalysts. The catalysts employed are soluble in organic solvents and allow for more rapid reactions under milder conditions. This chapter explains that dicyclopentadiene can be hydrogenated conveniently over a platinum catalyst in a Parr apparatus. Technical-grade dicyclopentadiene is purified by distillation under aspirator pressure through a short column. The hydrogenation of phenols appears to be a straightforward route to cyclohexanols, but the necessary conditions are frequently inconvenient, requiring high pressures and high temperatures. The rhodium catalyst is employed in the hydrogenation of p-hydroxybenzoic acid. The resulting mixture of cis and trans products is separated by virtue of the ready formation of the lactone of the cis product, which is then hydrolized to the hydroxy acid. The procedures given in the chapter are typical of low-pressure reactions.
Implementation of Telemedicine in Pediatric and Neonatal Transport.

Abstract Objective Telemedicine uses video technology to communicate visual clinical information. This study aimed to implement telemedicine in pediatric and neonatal transport, assess its value, and identify barriers. Methods This prospective study implemented telemedicine before transport to a tertiary care children's hospital. A preimplementation survey assessed attitudes toward telemedicine and perceived barriers. During the 12-week pilot, a video connection was initiated between transport and medical control. We collected survey results measuring telemedicine usefulness and hindrance after each use. A postimplementation survey assessed opinions about when telemedicine was useful. Results Initially, 82% of users had no direct experience with telemedicine. Perceived utility and burden of telemedicine varied significantly by department. During the study, telemedicine was offered 65% of the time, initiated in 47% of cases, and successful in 30% of cases. The greatest barrier was connectivity. Over time, transport members and physicians found telemedicine to be significantly more useful. In 14 cases, telemedicine changed patient outcome or management. Providers who reported a change in management rated telemedicine as significantly more useful. Conclusion This prospective pilot successfully implemented telemedicine before pediatric transport. Telemedicine was more useful in patients with visual findings on examination and, in some cases, changed the clinical outcome.
The role of photoinduced charge transfer for photocatalysis, photoelectrocatalysis and luminescence sensing in metal–organic frameworks

Metal–organic frameworks (MOFs) have emerged as promising porous optoelectronic compositions for energy conversion and sensing applications. The enormous structural possibilities, the large variety of photo- and redox-active building blocks along with several post-synthetic functionalization strategies make MOFs an ideal platform for photochemical and photoelectrochemical developments. Because MOFs assemble all the active building units in a dense fashion, the non-aggregated yet proximally positioned species ensure efficient photon absorption to drive photoinduced charge transfer (PCT) reactions for energy conversion and sensing. Hence, understanding the PCT processes within MOFs as a function of the topological and electronic structures of the donor–acceptor (D–A) moieties can provide transformative strategies to design new low-density compositions.
How to Govern Facebook: A Structural Model for Taxing and Regulating Big Tech

Digital platforms such as Facebook create value by connecting users, vendors, and contractors. Their strong supply and demand economies of scale can give them market power, and have led to increasing calls for special regulations and taxes. We construct and illustrate an approach for structural modeling of digital platforms. The model allows for heterogeneity in demand elasticity, disutility from advertising, and network effects across users. We paramaterize our model using a survey of over 57,000 US internet users on their demand for Facebook's eponymous application. Facebook creates $14 billion in social value per month, with consumer surplus concentrated among female and older users of Facebook. The most valuable friendships on Facebook are worth in excess of 50 cents per month, but most are worth far less, with connections to men more valuable on a per-friend basis. We find that Facebook has too low a level of advertising relative to their short-term profit maximizing strategy. Imputing their shadow value from maintaining a large user base, we estimate that the welfare lost from Facebook's market power, compared to the first best of a social welfare maximizing Facebook, is 9.6% of current social value, or $1.3 Billion per month. We then simulate six proposed policies for government management of digital platforms, taking Facebook's optimal response into account. Taxes are mostly incident on Facebook profit and properly targeted taxes can even raise consumer surplus. Achieving perfect competition in social media would raise social surplus from Facebook by 4.8% of current value. But a botched regulation that left the US with two smaller, non-competitive social media monopolies would decrease social surplus by 84.7%.
Visualization in the Analysis Cycle of Observational Data

The analysis cycle of observational data is expanded by visualization. To increase scientific productivity in the data analysis process it is necessary for the visualizations (visual data representations) to be expressive and effective. Additionally, the use of tools to visualize data must allow the scientist to concentrate on exploring scientific data rather than tackling a complex software environment. The paper also introduces STAR (Scientific Toolkit for Astrophysical Research), a software system that is designed to increase the productivity of astrophysicists through visualization.
Spatio-weighted information fusion and DRL-based control for connected autonomous vehicles

While on-board sensing equipment of CAVs can reasonably characterize the surrounding traffic environment, their performance is limited by the range of the sensors. By integrating short- and long-range information, a CAV can comprehensively construct its surrounding environment, thereby allowing it to plan both short and long-term maneuvers. Coalescing local information and downstream information is critical for the CAV to make safe and effective driving decisions. While literature is replete with CAV control approaches that use information sensed from the local traffic environment, studies that fuse information from various temporal-spatial instances to facilitate CAV movements is limited. In this paper, we propose a Deep Reinforcement Learning (DRL) based approach that fuses information obtained (via sensing and connectivity) on the local downstream environment for CAV lane changing decisions. We adopt learning-based techniques to provide an integrated solution that incorporates the information fusion and movement-decision processor. We also determine the optimal connectivity range for each operating traffic density. We anticipate that deployment of the proposed algorithm in a CAV will facilitate reliable proactive driving decisions and ultimately enhance the overall operational efficiency of CAVs in terms of safety and mobility.
Researching language in superdiverse urban contexts. Exploring methodological and theoretical concepts: edited by Clare Mar-Molinero, Bristol, UK; Blue Ridge Summit, PA, Multilingual Matters, 2020, 44.95 Euros, ISBN-13: 978-1-78892-646-1 (hbk) ISBN-13: 978-1-78892-645-4 (pbk)

This edited volume is invaluable in many ways. The chapters draw from theoretical and methodological contributions in the social sciences and the humanities and understand multilingualism’s social ...
Crisis narrative and the paradox of erasure: Making room for dialectic tension in a cancel culture

Abstract This study analyzed a crisis situation that a university faced when an historical artwork considered to be racially progressive when it was created nearly 70 years ago has been deemed racist in contemporary times. The university attempted to address criticisms by providing context to the artwork, explaining its creation and history as well as by creating companion artwork to lessen its offensiveness, but none of those attempts assuaged critics. We view the case through the lenses of narrative theory, dialectical tensions, and the paradox of erasure while recognizing the challenges organizations face navigating the limited space for competing narratives in a “cancel culture.” We add to and codify a typology of erasure in public relations and offer recommendations for universities dealing with crises that have competing interpretations of highly charged, socio-political issues, such as those stemming from racial injustice, at their center.
Observations of dissolved oxygen variability and physical drivers in a shallow highly stratified estuary

Abstract Evaluating the role of long-term anthropogenic changes on dissolved oxygen (DO) in coastal systems is often a challenge due to variability in a system and measurement sensitivity to spatial and temporal trends. Physical processes can significantly modify the DO variability and act as a major driver of uncertainty when it comes to quantifying the bio-chemical changes associated with the DO budget. Stratification has been observed to be a dominant factor in controlling the hypoxic conditions that can develop in Mobile Bay, AL, a shallow highly stratified estuary prone to episodic hypoxia. Using CTD transect data and long-term water quality monitoring stations the variability of DO was examined throughout Mobile Bay. This study examined the physical drivers of these trends and highlighted the role stratification, temperature, and advection play in driving the bay wide variability. Under stable conditions, the spatial trend in Mobile bay will reflect the along-estuary gradient. When stable conditions don't occur due to random episodic mixing events and cross estuary exchange, the Bay can be driven by a number of factors: the along-estuary gradients, time since the previous mixing event, level of stratification, and biochemical oxygen demand. The combination of these elements provides an increased understanding of the complex dynamics driving low DO in this system. Long-term trends show the DO is decreasing in Mobile Bay based on changes in DO in the shipping channel, northern region, and Bon Secour region.
Spectroscopic Investigation of the High-Pressure Behavior of Aliphatic Hydrocarbon: Implications for Planetary Processes

Octadecane (C18H38) is an aliphatic hydrocarbon that is abundant in carbonaceous chondritic meteorites. It is debated whether these hydrocarbons found in the meteorite are pristine or are a result ...
Overcoming the Tyranny of Distance: Culture Contact and Politics

Archaeologists have devised many different frameworks for treating the organizational effects of interregional interaction. Inner Asian statehood must be understood from the vantage point of multi-regional interaction and therefore requires a clear statement of the relationship between long-distance relationships, exchange, and political organization. By drawing on the anthropological concept of entanglement, this chapter sets out a model for social interaction, interregional contacts, and local politics that is suitable for the Inner Asian case study.
Computation for Circulation in Stratified Lakes

A mathematical method is developed for calculating the steady-state, three-dimensional, wind-driven circulation in a large stratified lake of arbitrary bottom topography and shape on a rotating earth. The stratification is modeled by a two-layer structure in which the hypolimnion and the epilimnion are considered as two distinct layers with different densities and eddy viscosities. The thermocline location responds sensitively to the applied wind stress and has an important effect on the circulation velocity. An off-shore wind is the primary cause of the cold water up-welling near the shore due to the movement of the thermocline. The surface current velocity generally has a smaller magnitude and greater deflection angle than in the homogeneous case except near the boundaries. The volume transport is strong and in the downwind direction near the shore in the epilimnion and near the deep center in the hypolimnion.
Growth Mechanism and Stability Study on the Fe3S4 Nanocrystals Synthesized Under Thermal and Humid Conditions

Greigite (Fe3S4) is important magnetic mineral that can not only instruct reducing environment but also provide paleomagnetic signal for the paleoenvironment research. Generally Fe3S4 exists as an unstable intermediate, whose preparation condition is rigorous. Previous studies have accumulated rich results, but the research on its stable conditions, formation mechanism, and evolution process remains to be verified. This study simulates the mineral growth and carries out experimental research systematically under thermal and humid conditions. Pure Fe3S4 is synthesized under the conditions of 200 °C, t = 30 h, pH = 4–5. The morphology of Fe3S4 is nanoscale particles. Fe3S4 stably exists at 200 °C, t = 30 h, and transforms to FeS2 with increasing time. The experimental results broaden the stability range of Fe3S4 in the Fe–S binary phase diagram. This study has typomorphic significance on geological conditions and provides a scientific basis for the preparation of Fe3S4 nano-magnetic materials.
MOTORCYCLE INTEGRATED BRAKES: HUMAN FACTORS CONSIDERATIONS AND BRAKING PERFORMANCE

The results of three studies are described in which motorcyclists rode motorcycles equipped with separated front and rear brakes and with integrated brakes, and carried out braking tests from 40.3km/h on dry and wet pavements. It was found that integrated front and rear brakes, compared with separated brakes, produced mean increases in decleration of 30–70% on dry pavements and 27–55% on wet pavements. It was concluded that, because accident investigations have shown that motorcyclists only use the front brake with the rear (foot) brake about half the time and often modulate the brakes ineffectively, a substantial proportion of motor–cycle crashes could be reduced in severity by the use of integrated brakes.
Building a Foundation for School Leadership: An Evaluation of the Annenberg Distributed Leadership Project, 2006-2010

Leading school change is a challenging endeavor. Successful leadership requires strategic and sustained effort, particularly in the shifting and uncertain environment of urban public schools. The concept of distributed leadership—in which multiple actors tackle the challenges of school leadership in concert—is a promising way to strengthen professional practice and thereby improve the educational experiences of all students. The Annenberg Distributed Leadership (DL) project was one of the first efforts in the nation to deliberately take on the challenge of designing and implementing a concerted effort to build distributed leadership capacity in a diverse set of urban schools to improve the quality of teaching and learning. The DL project featured the careful selection of leadership team members to identify and lead instructional improvement efforts; ample professional development to build cohesive teams and help members understand the motivational, psychological, and pedagogical aspects of advocating instructional change; resources to apply to the task; and ongoing school-based coaching to guide leadership team efforts. This report describes the Consortium for Policy Research in Education’s mixed-method evaluation of the DL project. The evaluation featured a cluster randomized control trial, where schools first agreed to participate in the study, and then were chosen by lottery to participate in the DL project or serve in the comparison group. Overall there were 16 DL schools and 21 comparison sites in the evaluation. Disciplines Curriculum and Instruction | Educational Assessment, Evaluation, and Research | Educational Leadership | Educational Psychology | Teacher Education and Professional Development | Urban Education Comments View on the CPRE website. This report is available at ScholarlyCommons: http://repository.upenn.edu/cpre_researchreports/67 CONSORTIUM FOR POLICY RESEARCH IN EDUCATION
What is at Stake in Debates among Normative Realists

One class of central debates between normative realists appears to concern whether we should be naturalists or reductionists about the normative. However, metaethical discussion of naturalism and reduction is often inconsistent, murky, or uninformative. This can make it hard to see why commitments relative to these metaphysical categories should matter to normative realists. This paper aims to clarify the nature of these categories, and their significance in debates between normative realists. I develop and defend what I call the joint-carving taxonomy, which builds on David Lewis� notion of elite properties. I argue that this taxonomy is clear and metaphysically interesting, and answers to distinctive taxonomic interests of normative realists. I also suggest that it has important implications for the project of adjudicating debates among normative realists.
DNA polymerase III from Saccharomyces cerevisiae. I. Purification and characterization.

Abstract Yeast cells from a wild type or protease-deficient strain were lysed in the absence or presence of protease inhibitors and the extracts analyzed by analytical high pressure liquid chromatography on diethylaminoethyl silica gel. Conditions that inhibited protease action caused elution of a novel DNA polymerase activity at a position in the gradient distinct from the elution positions of both DNA polymerase I and II. In large scale purifications, this DNA polymerase, called DNA polymerase III, copurified with a single-stranded DNA dependent 3'-5' exonuclease activity, exonuclease III, to near homogeneity. Glycerol gradient centrifugation partially dissociated the complex to yield two peaks of exonuclease III activity, one at 7.7 S together with the DNA polymerase, and one at 4.0 S without polymerase activity. Gel filtration indicated that the complex has a molecular mass greater than 400 kDa. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate indicated that the complex consists of several subunits: 140, 62, 55, and 53 kilodaltons, some of which may be proteolysis products. The exonuclease component of the complex can excise single nucleotide mismatches providing a base-paired primer-template which can be elongated by the DNA polymerase. Under replication conditions, the complex exhibits a measurable turnover rate of dTTP to dTMP and it contains no primase activity. The enzymatic activities of the 3'-5' exonuclease are consistent with a proofreading function during in vivo DNA replication. A second exonuclease activity, exonuclease IV, separated from the complex late in the purification scheme. It degrades both single-stranded and double-stranded DNA in the 5'----3' direction.
Mutations of L293 in transmembrane two of the mouse 5-hydroxytryptamine3A receptor alter gating and alcohol modulatory actions

1 The goal of this study was to determine whether mutations of L293 at the 15' position of TM2 in the 5-HT(3A) receptor alter macroscopic current kinetics, and if these changes could account for alterations in alcohol modulation. Receptor function was assessed in Xenopus oocytes under voltage-clamp and in HEK293 cells with whole-cell patch-clamp recording and rapid drug application. 2 Examination of responses of L293C and L293S receptors to agonist alone revealed enhanced activation, deactivation, and desensitization rates relative to the wild-type receptor. The L293G mutation produced marked slowing of deactivation and desensitization rates. Increased potency of 5-HT and increased efficacy of the partial agonist, DA, was also observed in these mutant receptors. 3 Ethanol and trichloroethanol (TCEt) enhancement of receptor function was reduced or eliminated in receptors containing L293 mutations to C, G, or S. The L293I mutant receptor retained ethanol and TCEt sensitivity. Ethanol and TCEt enhanced activation rate in the wild-type, but not the L293G and L293S receptors. No relationship was observed between any physicochemical property of the substituted amino acids and the change in alcohol potentiation of function. 4 The changes in receptor-channel properties in the mutant receptors support the idea that the L293 residue has important roles in channel gating. Our findings indicate that loss of allosteric modulation by alcohols is not related in any simple way to changes in channel kinetic properties brought about by L293 mutants. We did not observe any evidence that L293 is part of an alcohol binding site.
A qualitative model for barriers to software reuse adoption

With the increased pressures to deliver software applications at a faster rate and at a lower cost, software reuse is rapidly becoming an influential technology for software development. In this paper, software reuse is viewed as a systematic approach, encompassing all attempts to leverage software assets across systems by reusing them in development efforts. This paper focuses on grounding a descriptive and explanatory theory of the individual and organizational barriers associated with the adoption of reuse. A case study research method was used. A series of five cases were selected on the basis of theoretical replication. The five sites share commonalties in issues critical to the research. The findings of this research indicate that barriers occur at both the individual and at the organizational level. One of the key findings was that barriers at the individual level are actually a consequence of the interaction of barriers caused at the organizational level. Several other significant findings emerged as well.
Fundamental physics with cold and ultracold neutrons

Resumen en: Cold and ultra-cold neutrons are ideal tools for testing fundamental symmetries of the electroweak interaction. The emphasis is on precision measurement...
Biochemistry of Vibrio cholerae Virulence III. Nutritional Requirements for Toxin Production and the Effects of pH on Toxin Elaboration in Chemically Defined Media

The investigations described in this report concern the metabolic and physiologic parameters governing cholera enterotoxin production in chemically defined growth media. The results indicate that the minimal nutritional requirements for growth of pathogenic Vibrio cholerae are the same as those for toxin production, and that toxin production parallels growth of the organisms. Studies of the relationship between toxin accumulation and pH reveal that toxin biosynthesis can be separated from toxin release. Toxin is synthesized below pH 7.0, but release and accumulation of extracellular toxin occur only at neutral or alkaline pH values.
Validation of the NITI Endoluminal Compression Anastomosis Ring (EndoCAR) device and comparison to the traditional circular stapled colorectal anastomosis in a porcine model.

The purpose of this study was to determine whether the characteristics of compression anastomoses created by a new device are comparable to existing stapler technology. A total of 18 pigs were stud...
Technological Change in the Machine Tool Industry, 1840–1910

Technological change has come to absorb an increasing share of the attention of the economist in recent years. Several attempts have been made to assess the quantitative importance of technological change, as opposed to increases in factor supplies, in accounting for the secular rise in per capita incomes in the United States. It appears, in all these studies, that technological changes (shifts in the production function) have been far more important than has the mere growth in the supplies of capital and labor inputs, as conventionally measured (movement along an existing production function). In a sense, this should be cause for deep concern, since the comparative neglect of the process of technological change (with the major exceptions until very recent years, of the works of Marx, Schumpeter, and Usher) suggests a serious malallocation of our intellectual resources. If the studies of such people as Abramovitz and Solow are even approximately correct with respect to orders of magnitude, then the contribution of technological change to rising per capita incomes absolutely dwarfs the contribution from a rising but qualitatively unchanging stock of capital. It would appear that we have indeed been playing Hamlet without the Prince.
Impedance of Amalgam-Dentin Interface in Cat Tooth

The impedance between two amalgam electrodes implanted in the maxillary canine of a cat was measured at various frequencies between 0.02 kilohertz (kHz) and 100 kHz. When plotted on the X-R plane as a function of frequency, two types of impedance loci were obtained. One resembled a circular arc at low frequencies, whereas the other was parabolic or exponential in form. The circular-arc loci are similar to those calculated from membrane models. The parabolic or exponential loci are predicted by a polyelectrolyte model.
The effect of growth and thyroid hormones upon the removal by lavage of calcium and strontium from the skeleton of the rat.

Intraperitoneal lavage was used to remove some of the previously deposited radiostrontium and radiocalciuin from the skeletons of rats. The efficiency of radioisoiope removal was taken as an index of the incorporation of the radionuclide from the labile into the less-labile portions of bone. The data showed that removal efficiency decreased with time from dosing until the start of lavage. In hypophysectomized rats as compared to normals, removal efficiericy was increased at 24 hr after lavage but not at 8 or 48 hr. Supplying growth hormone to hypophysectomized rats decreased the amount of radioisotope that could be removed by lavage at 24 hr after dosing. Thiouracil, when fed to intact rats, increased the amount of radioisotopes that could be removed: however, thiouracil fed to hypophy-sectomized rats receiving growth hormone did not produce this response.
Country as brand, product, and beyond: A place marketing and brand management perspective

This paper examines how widely held country images affect attitudes towards a country's products and services and ability to attract investment, businesses and tourists. It assesses the role of strategic marketing management in promoting the country's image, attractiveness and products.
EFFECTS OF HEAT TREATMENT AND PROTEIN CONCENTRATION ON THE RHEOLOGY OF BOVINE PLASMA PROTEIN SUSPENSIONS

Changes in rheology during the heating of bovine plasma protein suspensions were examined at temperatures between 50°C and 90°C and for concentrations ranging from 6-12% protein isolate over a 3-hr period. An annular pumping device was used to determine a viscosity index for the suspensions. A model was developed to explain the data. The viscosity index increased exponentially with time at a particular temperature while being linearly dependent upon the concentration. The Arrhenius Equation described the effect of temperature on the rate of change of the viscosity index during heating.
Metric-driven harm: An exploration of unintended consequences of performance measurement

Performance measurement is an increasingly common element of the US health care system. Typically a proxy for high quality outcomes, there has been little systematic investigation of the potential negative unintended consequences of performance metrics, including metric-driven harm. This case study details an incidence of post-surgical metric-driven harm and offers Smith's 1995 work and a patient centered, context sensitive metric model for potential adoption by nurse researchers and clinicians. Implications for further research are discussed.
Effects of reserpine on the copulatory behavior of male rats.

Abstract Each of 27 male rats received three tests of copulatory behavior, one following saline injection, one following injection of 0.5 mg/kg reserpine, and one following injection of 1.0 mg/kg reserpine. Reserpine had a specific facilitatory effect on male copulatory behavior, causing significant reductions in the number of intromissions and in the time required to attain ejaculation in the second ejaculatory series.
High-Speed Low-Power Small-Area Accumulator Designs for Direct Digital Frequency Synthesizers

This paper presents high-speed low-power small-area accumulator designs to be used in DDFS systems. To reduce the Numerically Controlled Oscillator (NCO) design complexity and size, only the most significant bits of the accumulator drive the phase to amplitude mapping block. Those bits need to be updated on every sampling clock, while the least significant bits of the accumulator are not visible to the rest of the DDFS design and can be updated less frequently, which motivated the development of new accumulator designs. Without performance degradation, the proposed designs relieve constraints in implementation, and hence they can be employed for GHz-range DDFS, reduce power consumption up to 82% compared to standard accumulator design, and minimize chip area. For further power reduction, the proposed designs place the phase modulation adder at the front of the accumulator.
Host defense against pulmonary infection in neonates

Abstract It is well known that neonatal immune function is immature compared to adults and that ontogeny of the immune system continues for some time postnatally. This renders infants particularly susceptible to pulmonary bacterial and viral infections often associated with childhood. Innate immune responses are less intense and delayed compared to adults. Antigen presentation is immature in that antigen presenting cells are slow in upregulating costimulatory molecules. This results in reduced T-cell responses including T-cell help and cytotoxic lymphocytes (CTL) function. B-cell responses suffer from the lack of T-cell help. The maturation process of immune mediators in newborns corresponds with postnatal development of the lungs and may be a mechanism that keeps inflammation from causing damage to developing lungs.
Adiponectin is Associated with Increased Mortality and Heart Failure in Patients with Stable Ischemic Heart Disease: Data from the Heart and Soul Study

Objective Serum adiponectin protects against incident ischemic heart disease (IHD). However, in patients with existing IHD, higher adiponectin levels are paradoxically associated with worse outcomes. We investigated this paradox by evaluating the relationship between adiponectin and cardiovascular events in patients with existing IHD.
Spatial Model of Movement and Foraging in Harvester Ants (Pogonomyrmex) (II): The Roles of Environment and Seed Dispersion

Individual-based models provide a framework for understanding individual and collective behavior of a complex system, such as social insects. We applied an individual-based simulation model of foraging of the western harvester ant (Pogonomyrmex occidentalis) to two environments, shrub-steppe and shortgrass-steppe, in which the movement characteristics of individual ants differed according to vegetation structure. Using regular, clumped, and fractal seed dispersions, we simulated the influence of environment and foraging speed on rates of seed harvest by a colony of ants. The relative importance of individual and co-operative foraging behavior, where ants use spatial memory or chemical recruitment, was also explored in conjunction with environment and seed dispersion. Our replicated modeling "experiment" permitted us to study the three-way interaction among environment, seed dispersion, and behavior in the rates of seed harvest by ants. When foraging individually or co-operatively at observed movement rates, ants had similar harvest rates of seeds in a regular dispersion. In contrast, ants rapidly removed seeds from a fractal dispersion of seeds when foraging co-operatively. This suggests that differences in ant behavior were less important to the rate of food intake when foraging in a homogeneous resource dispersion, whereas co-operative foraging was most responsive to food resources that were spatially correlated over a range of scales. A slight difference was found between observed and modeled distributions of ant foraging distances in the shrub-steppe environment, while observed and modeled distributions were not significantly different in the shortgrass-steppe. Thus, our simulation model captured many of the foraging properties of individual ants, although it did not always accurately describe the spatial distribution of foraging ants. Our application to P. occidentalis shows that processes operating in a social unit, such as the rate of food intake by an ant colony, are strongly influenced by the interplay of the environment, resource dispersion, and the behavioral responses of individuals to food resources. This interaction arises because of the spatial properties of both foraging ants and seed resources, which suggest that spatially explicit modeling approaches may yield different insights into foraging than those based on energetic criteria.
The real cost of making customers wait

This paper considers the problem of estimating the service capacity that should be provided in a situation in which additional capacity may result in greater demand. Difficulties with conventional approaches are discussed. It is shown to be possible to estimate optimal service capacity in a relatively convenient manner from transaction data in some situations. This procedure has pedagogical as well as practical uses.
On the Fluorescence of NAD(P)H in Whole-Cell Preparations of Tumours and Normal Tissues

1 The ‘blue-shift’ of the fluorescence maximum of NAD(P)H bound to many proteins offers a means of studying coenzyme binding in whole cells. In earlier work there was a discrepancy between the fluorescence maximum seen in whole tissues (liver, kidney, heart-maximum at 460–470 nm, characteristic of NAD(P)H in solution) and in mitochondria isolated from them (maximum at 440 nm). 2 Study of the fluorescence-emission spectra and absolute absorption spectra of some types of isolated cell suspensions and tissue slices, now suggests that a blue shift of NAD(P)H fluorescence in cells may be disguised by an inner-absorption effect, since there is a marked change of absorbance from 410 to 460 nm. 3 The change of absorbance between 410 and 460 nm, and hence the distorting effect of inner absorption, varies considerably in different cell types. 4 The influence of inner-absorption on the fluoresence also varies with the concentration of cell suspensions, or thickness of slices; working at low cell concentrations, or extrapolation to zero thickness of slices, allows estimation of the wavelength of maximal NAD(P)H fluorescence, undistorted by inner-absorption. 5 Undistorted fluorescence maxima were thus estimated to be at approximately 440 nm for suspensions of bakers' yeast and rat-liver cells, and for liver slices. Maxima close to 460 nm were given by Ehrlich tumor cells and slices of hepatoma 3924 A. Fluorescence of NAD(P)H in cytosolic and mitochondrial compartments can be distinguished with appropriate substrates and inhibitors. In a given cell type, the fluorescence maximum in the two compartments was indistinguishable. 6 The difference between the fluorescence maxima of NAD(P)H in liver and hepatoma 3924 A is considered in the light of the known differences of dehydrogenase enzyme activity in the two tissues.
Strategies to retain participants in a long-term HIV prevention randomized controlled trial: lessons from the MINTS-II study.

Achieving satisfactory retention in online HIV prevention trials typically has proven difficult, particularly over extended timeframes. The overall aim of this study was to assess factors associated with retention in the Men’s INTernet Study II (MINTS-II), a randomized controlled trial of a sexual risk reduction intervention for men who have sex with men. Participants were recruited via e-mails and banner advertisements in December, 2007 to participate in the MINTS-II Sexpulse intervention and followed over a 12-month period. Retention across the treatment and control arms was 85.2% at 12 months. Factors associated with higher retention included: randomization to the control arm, previous participation in a study by the research team, e-mail and telephone reminders to complete a survey once it was available online, and fewer e-mail contacts between surveys. The results provide evidence that achieving satisfactory retention is possible in online HIV prevention trials, and suggest best practices for maximizing retention.
The validity of the successive intervals method of psychometric scaling

The degree to which scale values computed by the method of successive intervals diverge from theoretically “true” values is seen to be due to three types of error: error due to inequalities in variances of the distributions from which the scale values are computed, error due to non-normality of the distributions, and sampling error. The contribution of each type of error to the total error is evaluated; the latter is seen to be surprisingly small under appropriate conditions. Certain aspects of the formal methodology underlying scaling procedures are also briefly considered.
Effect of Surface Ambient on Manganese Diffusion in Gallium Arsenide

Data are presented showing the effects of diffusion sources, surface encapsulation, and As overpressure on Mn diffusion in GaAs. Four different Mn-containing sources are used, including Mn, Mn,MN3As, and MnAs granules as well as Mn thin film deposited directly onto GaAs substrate. Smooth surface morphology with high surface Mn concentration can be obtained using MnAs (and in certain conditions, Mn3As) as diffusion source; different degrees of surface degradation are observed if otherwise sources are used as diffusion source. Data also show surface encapsulation and As overpressure have significant effects on the reaction between the source and GaAs and the Mn diffusion in GaAs.
Uses of the microtiter technique in clinical pathology

Abstract Adaptations of the microtiter system to routine clinical serological procedures are described. Details of these methods are outlined together with a comparison of results with those obtained by conventional techniques. An improved method of reading is presented. The advantages, disadvantages, and the possible role of this system in the routine laboratory are discussed.
Extending the field of view of an adaptively corrected telescope by longitudinal pupil displacement

A simple scheme is proposed to increase the corrected field of view of a telescope equipped with adaptive optics. The optical system's entrance pupil is projected forward into the atmosphere and is slightly reduced in size. The field in any given direction is then imaged through just a portion of the main aperture, while the full aperture is used to collect light from the reference beacons, which may be either natural stars or laser beacons. The enlargement of the field of view is proportional to the reduction in pupil size and therefore comes at some cost in flux and resolution. A numerical simulation shows that the trade-off is modest and may in many cases be advantageous.
Impact of I 2 L

Technological, business and economic factors that may limit or accelerate the use of I2L technology in logic, memory and linear/analog applications will be surveyed by I2L, CMOS, N-channel and bipolar specialists.
Luteotrophic and Luteolytic Actions of LH in Hypophysectomized, Pseudopregnant Rabbits

The ability of LH to sustain the structure and function of corpora lutea (CL) for one week after hypophysectomy was studied in 95 pseudopregnant rabbits. When administered in large sc doses, 125 or 250 μg twice daily (b.i.d.), LH consistently failed to maintain CL regardless of whether the treatment was initiated between 2 to 3 or at 12 hr after hypophysectomy. FSH likewise failed to maintain the CL, although doses of either 200 or 300 μg b.i.d. prevented follicular regression. When smaller doses of LH were combined with FSH, luteal structure and function were maintained to a variable extent and the degree of maintenance was directly related to the weight of the ovary at autopsy. Since luteal maintenance in the rabbit depends on estrogen, these data suggest that small doses of LH, which sustain estrogen secretion from follicular tissue, will be luteotrophic. Larger doses of LH, which suppress estrogen secretion either by luteinization of follicles or by depletion of cholesterol esters, will be luteolytic....
Effects of the Television Spots on Images of Dole and Clinton

This experimental study of the 1996 television spots conducted in a series of locations during the general election campaign indicates that exposure to Dole's spots enhanced his image in September, but October exposures resulted in a negative image effect for Dole and a positive one for Clinton. Effects of spot exposure on independents and on women were particularly significant. The results also show that technological manipulations in negative spots can achieve the desired effects for ad sponsors.
Bilingual language assessment: a meta-analysis of diagnostic accuracy.

Purpose To describe quality indicators for appraising studies of diagnostic accuracy and to report a meta-analysis of measures for diagnosing language impairment (LI) in bilingual Spanish–English U...
Renin–angiotensin–aldosterone system (RAAS) pharmacogenomics: implications in heart failure management

Blockade of the renin–angiotensin–aldosterone system (RAAS) with ACE inhibitors has been a cornerstone of heart failure therapy for over 15 years. More recently, further blockade of RAAS with aldosterone antagonists and angiotensin receptor blockers (ARBs) has been studied. While these therapies have certainly improved outcomes in the treatment of heart failure, morbidity and mortality remain extremely high. Furthermore, polypharmacy and complex regimens of seven medications on average is the norm for management of heart failure. This results in increased costs, patient burden, and uncertainty as to the best course of therapy. The ability to personalize patients’ therapeutic regimens using pharmacogenomics has the potential of providing more effective and efficient use of RAAS-modulating medications. This review highlights the implications of major RAAS pharmacogenetic studies, while outlining future directions for translation to practice.
A hypothesis for the interaction of heme and arachidonic acid in the synthesis of prostaglandins.

Abstract A model is proposed for the interaction of arachidonic acid with the heme associated with the cyclo-oxygenase enzyme which synthesizes prostaglandin endoperoxides. According to this concept, arachidonic acid attaches with its carboxylic acid residue to one ligand of the Fe ++ in heme, then curls around the outside of the protoporphyrin to react with a molecule of oxygen associated with the ligand of the Fe ++ on the other side of the protoporphyrin with addition of O 2 at the C11 carbon, ring closure across C8–12, formation of the C9–11 endoperoxide and then addition of a second oxygen at C15 with an allylic shift of the double bond. This concept may resolve several experimental findings relating to the mechanism of prostaglandin synthesis and can account for much of the stereospecificity in the conversion of arachidonic acid to prostaglandin G 2 .
A review of reprocessing techniques of flexible nasopharyngoscopes

To provide assistance to otolaryngologists to decide the best manner in which to reprocess flexible nasopharyngoscopes, a review of existing English language medical literature regarding the methods of flexible endoscope reprocessing was performed, including previously published guidelines from other medical disciplines. Multiple steps were confirmed to be critical to effectively reprocess flexible nasopharyngoscopes. High-level disinfection has been determined to be the minimum level of disinfection required for reprocessing of flexible nasopharyngoscopes. Several steps are important in all reprocessing techniques, including manual cleaning, leak testing, cleaning with an enzymatic agent, high-level disinfection, and drying with vertical storage. Three techniques are available to achieve high-level disinfection: manual disinfection with a liquid disinfectant/sterilant, use of an automated endoscope reprocessor, and use of a disposable sheath. Achieving high-level disinfection of flexible nasopharyngoscopes can be accomplished by a variety of methods. Strict adherence to recommended procedures is critical.
Characterizing local traffic contributions to particulate air pollution in street canyons using mobile monitoring techniques

Abstract Traffic within urban street canyons can contribute significantly to ambient concentrations of particulate air pollution. In these settings, it is challenging to separate within-canyon source contributions from urban and regional background concentrations given the highly variable and complex emissions and dispersion characteristics. In this study, we used continuous mobile monitoring of traffic-related particulate air pollutants to assess the contribution to concentrations, above background, of traffic in the street canyons of midtown Manhattan. Concentrations of both ultrafine particles (UFP) and fine particles (PM 2.5 ) were measured at street level using portable instruments. Statistical modeling techniques accounting for autocorrelation were used to investigate the presence of spatial heterogeneity of pollutant concentrations as well as to quantify the contribution of within-canyon traffic sources. Measurements were also made within Central Park, to examine the impact of offsets from major roadways in this urban environment. On average, an approximate 11% increase in concentrations of UFP and 8% increase in concentrations of PM 2.5 over urban background was estimated during high-traffic periods in street canyons as opposed to low traffic periods. Estimates were 8% and 5%, respectively, after accounting for temporal autocorrelation. Within Central Park, concentrations were 40% higher than background (5% after accounting for temporal autocorrelation) within the first 100 m from the nearest roadway for UFP, with a smaller but statistically significant increase for PM 2.5 . Our findings demonstrate the viability of a mobile monitoring protocol coupled with spatiotemporal modeling techniques in characterizing local source contributions in a setting with street canyons.