cssi/SciSciGPT-SciSciNet huggingface dataset:
Volatilization kinetics of silicon carbide in reducing gases: an experimental study with applications to the survival of presolar grains in the solar nebula

The volatilization kinetics of single crystal α-SiC, polycrystalline β-SiC, and SiO_2 (cristobalite or glass) were determined in H_2-CO_2, CO-CO_2, and H_2-CO-CO_2 gas mixtures at oxygen fugacities between 1 log unit above and 10 log units below the iron-wustite (IW) buffer and temperatures in the range 1151 to 1501°C. Detailed sets of experiments on SiC were conducted at 2.8 and 6.0 log units below IW (IW-2.8 and IW-6.0) at a variety of temperatures, and at 1300°C at a variety of oxygen fugacities. Transmission electron microscopic and Rutherford backscattering spectroscopic characterization of run products shows that the surface of SiC exposed to IW-2.8 is characterized by a thin (<1 μm thick), continuous layer of cristobalite. SiC exposed to IW-6.0 lacks such a layer (or its thickness is <0.01 μm), although some SiO_2 was found within pits and along incised grain boundaries. In H_2-CO_2 gas mixtures above ∼IW-3, the similarity of the SiC volatilization rate and of its dependence on temperature and fO_2 to that for SiO_2 suggests that SiC volatilization is controlled by volatilization of a SiO_2 layer that forms on the surface of the SiC. With decreasing log fO_2 from ∼IW-3 to ∼IW-6, the SiC volatilization rate is constant at constant temperature, whereas that for SiO_2 increases. The independence of the SiC volatilization rate from the gas composition under these conditions suggests that the rate-controlling step is a solid-solid reaction at the internal SiC/SiO_2 interface. For gas compositions more reducing than ∼IW-6, the SiC volatilization rate increases with decreasing fO_2, with both bare SiC surfaces and perhaps silica residing in pits and along incised grain boundaries contributing to the overall reaction rate. If the volatilization mechanism and reaction rate in the solar nebula were the same as in our H_2-CO_2 experiments at IW-6.0, then estimated lifetimes of 1-μm-diameter presolar SiC grains range from several thousand years at ∼900°C, to ∼1 yr at 1100°C, ∼1 d at 1300°C, and ∼1 h at 1400°C. The corresponding lifetimes for 10-μm SiC grains would be an order of magnitude longer. If the supply of oxidants to surfaces of presolar SiC grains were rate limiting—for example, at T > 1100°C for P^(tot)= 10^(−6) atm and sticking coefficient = 0.01, then the calculated lifetimes would be about 10 yr for 10-μm-diameter grains, essentially independent of temperature. The results thus imply that presolar SiC grains would survive short heating events associated with formation of chondrules (minutes) and calcium-, aluminum-rich inclusions (days), but would have been destroyed by exposure to hot (≥900°C) nebular gases in less than several thousand years unless they were coated with minerals inert to reaction with a nebular gas.
Double Diastereoselection Operative During π-Facially Selective Addition of Chiral 1-Cyclopentenyllithium Reagents to (7R)-7-Methyl-7-Vinylbicyclo[3.2.0]Hept-2-En-6-One

Abstract Reaction of the title cyclobutanone with chiral cyclopentenyllithium reagents occurs exclusively from the convex face with low diastereoselectivity. Nonetheless, polycyclic networks with as many as nine stereogenic centers can be elaborated in very few steps.
Adolescent Sexual Activity and the Development of Delinquent Behavior: The Role of Relationship Context

Despite the well-established association between adolescent sexual activity and delinquent behavior, little research has examined the potential importance of relationship contexts in moderating this association. The current study used longitudinal, behavioral genetic data on 519 same-sex twin pairs (48.6% female) divided into two age cohorts (13–15 and 16–18 years olds) drawn from the National Longitudinal Study of Adolescent Health. Analyses tested whether adolescent sexual activity that occurred in romantic versus non-romantic relationships was associated with delinquency from adolescence to early adulthood, after controlling for genetic influences. Results indicated that, for both younger and older adolescents, common underlying genes influence both sexual behavior and delinquency. After controlling for these genetic influences, there was no within-twin pair association between sexual activity and delinquency in younger adolescents. In older adolescents, sexual activity that occurred in romantic relationships predicted lower levels of delinquency, both cross-sectionally and longitudinally, whereas sexual activity in non-romantic relationships predicted higher levels of delinquency. These results are consistent with emerging research that suggests that the psychological correlates of adolescent sexual activity may be moderated by the social context in which this activity occurs.
Treatment selection by constraint propagation: a case study in cutting fluid selection

The GREASE project is an investigation of the application of artificial intelligence to cutting fluid selection and blending for metal machining operations. The problem is to first diagnose the machining operations to determine what fluid characteristics are required, then to select a cutting fluid which satisfies the required characteristics. The problem is exacerbated by the need to select a single fluid to be used by multiple types of operations on a variety of materials. Diagnosis is relatively simple, but treatment specification is difficult due to the variety of operations to be handled.GREASE uses heuristic search in which the evaluation function is heuristically constructed. The construction of the evaluation function begins with the determination of the characteristics of an optimal fluid based on deep knowledge of the machining operations and materials. This is then altered heuristically according to problems diagnosed with the current fluid. Once the evaluation function is complete, it is used to select an existing fluid from the product line. GREASE has been tested extensively with results which equal that of the experts and has been field tested by the Chevron Corporation.
Opportunities for psychologists in health maintenance organizations: Implications for graduate education and training.

Recensement des roles actuels et des fonctions des psychologues dans les HMO (Health Maintenance Organizations) aussi bien dans le domaine de l'enseignement, de la recherche que de la therapie. Les changements perceptibles du marche doivent etre devances par des changements dans les programmes d'education et de formation des psychologues
Cognitive stigmergy: A study of emergence in small-group social networks

This paper proposes a model and theory of leadership emergence whereby (1) small social groups are modeled as small world networks and a betweeness metric is shown to be a property of networks with strong leadership, and (2) a theory of group formation based on stigmergy explains how such networks evolve and form. Specifically, dominant actors are observed to emerge from simulations of artificial termites constructing a wood chip network in a random walk, suggesting a correlation between various preferential attachment rules and emergent network topologies. Three attachment rules are studied: maximizing node betweeness (intermediary power), maximizing node degree (node connectivity), and limiting radius (size of the network in terms of network distance). The simulation results suggest that a preference for maximizing betweeness produces networks with structure similar to the 62-node 9-11 terrorist network. Further simulations of emergent networks with small world properties (small radius) and high betweeness centrality (strong leader) are shown to match the topological structure of the 9-11 terrorist network, also. Interestingly, the same properties are not found in a small sampling of human made physical infrastructure networks such as power grids, transportation systems, water and pipeline networks, suggesting a difference between social network emergence and physical infrastructure emergence. Additionally, a contagion model is applied to random and structured networks to understand the dynamics of anti-leader sentiment (uprisings and counter-movements that challenge the status quo). For random networks, simulated pro-leader (pro-government) and anti-leader (pro-rebel) sentiments are propagated throughout a social network like opposing diseases to determine which sentiment eventually prevails. Simulations of the rise of rebel sentiment versus the ratio of rebel to government sentiment show that rebel sentiment rises on less than 100% rebel/government sentiment when government sentiment is high (strong leadership), but requires greater than 100% rebel/government sentiment when government sentiment is low (weak leadership). However, when applied to the structured 9-11 terrorist network, rebel sentiment is slow to rise against strong leadership, because of the high betweeness structure of the 9-11 network. These results suggest a theory of how and why human stigmergy evolves networks with strong leaders, and why successful social networks are resilient against anti-leader sentiment. The author concludes that a combination of small world and high betweeness structure explain how social networks emerge strong leadership structure and why the resulting networks are resilient against being overthrown by a dissenting majority.
Lexical constraints and prepositional phrase attachment

Six experiments investigated how lexical constraints influence syntactic analysis during an ambiguous region of an isolated sentence. We focused on prepositional phrase (PP) attachment ambiguities in dative sentences such as “John gave a letter to his son …” to test some predictions of constraint-based lexicalist models. Processing difficulty was measured using word-by-word sensibility judgments (Experiments 1–3 and 5) and word-by-word reading times (Experiments 4 and 6). We found that both the timing and the type of lexical constraint information governed how it was used. A syntactic commitment was made early in the ambiguous region when one structure was supported by multiple constraints at the point of ambiguity. Thus, garden path effects were found for both “John gave a letterto his sonto a friend” and “Paul gave the scriptto the playto a girl.” (the locally ambiguous PP is italicized). The amount of processing difficulty experienced during the second PP was greatly reduced when the preposition in the first prepositional phrase was inconsistent with the verb's constraints on “recipient” PP's (e.g., “John gave a letter for/about his son to a friend”). In contrast, manipulating probabilistic constraints of the preposition had little effect on either judgments or reading times. These results support a constraint-based view of parsing in which those constraints that are encoded in competing lexical forms influence the strength with which syntactic alternatives are made available, while noncompeting constraints play a secondary role in ambiguity resolution.
Magnetostratigraphy of the late Tertiary Verde Formation, central Arizona

Abstract Paleomagnetic polarity data were obtained from nine sections of the Verde Formation, a late Tertiary carbonate-bearing lacustrine unit in central Arizona. This study tested the applicability of magnetostratigraphy as a geochronologic technique in a restricted terrestrial sedimentary basin, and its objective was to better define the age of the Verde Formation. Intensities of natural remanent magnetism (NRM) ranged from −7 to >10 −4 gauss. Although secondary components of viscous magnetization commonly were observed, alternating field demagnetization was successful in revealing the polarity of the primary NRM at almost all sites. Thermomagnetic analysis, partial thermal demagnetization of NRM, and polished section analysis together indicate that the primary NRM is a depositional remanence carried by detrital magnetite. Intrabasin stratigraphic correlation of the sections, together with K-Ar ages on interbedded and underlying volcanic rocks has allowed construction of a composite magnetostratigraphic column for the Verde Formation that is correlated with the late Cenozoic polarity time scale. The correlation indicates nearly continuous sedimentation in the Verde basin from ∼7.5 to ∼2.5 m.y. ago.
Computer Simulation of a Single Truss Tomato Cropping System

ABSTRACT THE development of a computer simulation model for greenhouse tomato crop management is discussed. The management model, based on a crop production model, will determine a production schedule designed to provide a continuous yield, optimize greenhouse space utilization, and predict production rates throughout the year.
An HR perspective: the global hunt for talent in the digital age

Purpose – The purpose of this paper is to provide the reader with a practical understanding of the dynamic changes in how resumes are handled by recruiters and the application of technology to the human resource (HR) functions not only of reading resumes, but also of how technology is making some of the initial decisions on how they are passed on to hiring managers. HR information system has changed the way talent is accessed, prescreened, sorted, and stored. Knowledge of these systems is imperative for the twenty‐first century job‐seeker.Design/methodology/approach – The authors interview industry practitioners regarding the use of resume scanning and identify the pros and cons of the systems from an industry perspective.Findings – These discussions find that technology will continue to impact HR group in the hospitality industry. As the HR teams find more and better ways to utilize the technology the applicant pool will have to adjust to ensure that they are not screened out because they are missing a “...
RIBBON DEVELOPMENTS IN THE URBAN BUSINESS PATTERN

(1959). RIBBON DEVELOPMENTS IN THE URBAN BUSINESS PATTERN. Annals of the Association of American Geographers: Vol. 49, No. 2, pp. 145-155.
Cholesterol Embolization: From Pathological Curiosity to Clinical Entity

In the two cases of multiple system disease due to atheromatous embolization presented, increasingly severe hypertension developed owing to renal involvement. One patient had acute pancreatitis from embolization to the pancreas. The second patient had mottling of the skin of the legs. Purple toes were present and gangrene developed in 3 toes. The possible influence of anticoagulant therapy in promoting peripheral cholesterol embolism is discussed. It is suggested that the "purple toe syndrome" may be a manifestation of cholesterol embolization secondary to anticoagulant therapy.
Synthesis and biological evaluation of Tc-99m-cyclopentadienyltricarbonyltechnetium-labeled octreotide.

Abstract Octreotide was labeled at its N -terminus with Tc-99m-cyclopentadienyltricarbonyltechnetium, and the biodistribution of the labeled conjugate was studied in adult female Sprague–Dawley rats. The synthesis began with the preparation of Tc-99m-(methoxycarbonylcyclopentadienyl)tricarbonyltechnetium from Tc-99m-pertechnetate using a novel double ligand transfer reaction; it was completed in a total of five steps, with an 8% overall radiochemical yield (15% decay-corrected). The 99m Tc-cyclopentadienyltricarbonyltechnetium-labeled octreotide conjugate ( 99m Tc-CpTT-octreotide) showed receptor-mediated uptake in the pancreas and adrenals, which was blocked (80% and 93%, respectively) by excess unlabeled octreotide. These studies illustrate a new method for labeling a peptide with Tc-99m through an organometallic linkage that is stable, nonpolar, and low molecular weight; it complements labeling approaches that utilize inorganic metal complexes.
Symmetric behavior-based trust: a new paradigm for internet computing

Current models of Internet Computing are highly asymmetric - a host protects itself from malicious mobile Java programs, but there is no way to get assurances about the behavior of a program running remotely. The asymmetry stems from a behavior-based security model: hosts ensure conformance to a given security policy by restricting the actions of programs. In contrast, security models that are based on cryptography (including code signing) are inherently symmetric by design but do not match the open architecture of the Internet and are unsuitable for reasoning about program behavior. We propose a new paradigm that combines the openness of the former with the symmetry of the latter and thereby enables completely new applications in a globally connected world.
Complementary Field Method For Interferometric Tomographic Reconstruction Of High Speed Aerodynamic Flows

A complementary field method has been devised for interferometric tomographic reconstruction of high-speed aerodynamic flows involving a shock. It is based on the reconstruction of the complementary field, which is the difference between the object field to be reconstructed and its estimate. The method is iterative in nature and incorporates a priori information. This study demonstrates advantages of the method in alleviating the deficiencies associated with computational reconstructors and measured data. Substantial reconstruction improvement is obtained, especially near a shock when its position is utilized as a priori information. Under the test conditions, convergence of the method is rapid.
Ultrasound Measurement of Two-Filler Concentrations in Polypropylene Compounds. Part 2: On-Line Calibration

An ultrasound system capable of measuring the concentration levels of two fillers, glass fibres and mica flakes, in polypropylene blends during extrusion compounding, has been successfully developed. The system is capable of operating under harsh conditions of the extruder settings while efficiently measuring the acoustic properties of the polymer melt. The attenuation and time-of-flight measurements of 1 MHz ultrasound waves propagating continuously through the polymer stream, prior to exiting the extrusion die, are used to characterise the morphology of the polymer blend and to determine the relative concentrations of blend additives. Prior work on the static calibration of the ultrasound set-up (Part I) has been used to evaluate the real-time performance of the system. The ultrasound measurements showed a good match with the laboratory analysis.
Relationship correspondence: similarities and differences in business response to complimentary versus complaining consumers

Abstract Maintaining and enhancing long-term business relationships with customers is essential to marketing-oriented organizations. For business such as consumer package goods manufacturers (CPGMs), who generally are removed from day-to-day contact with the ultimate customer, the handling of unsolicited consumer correspondence represents a unique relationship building opportunity. While relationship correspondence research to date has focused primarily on consumer complaints, this study investigated the extent to which CPGMs respond to both complaint and complimentary letters in a similar fashion. Although though several similarities are noted, paired analyses of CPGMs' responses to paired letters of praise and complaint revealed some inconsistencies. For example, responses to complaint letters were more likely to: 1) address specific consumer comments, 2) be longer, and 3) include a gift or coupon of greater monetary value. Praise responses were more likely to suggest other product uses or applications.
Epidemiology of Hunting Stand Injuries Presenting to US Emergency Departments, 2008-2013.

Objective To determine the epidemiology of injuries from hunting stands presenting to US emergency departments (EDs). Methods The National Electronic Injury Surveillance System (NEISS) database was queried for ED visits for the period 2008 through 2013 for hunting stand injuries and analyzed for age, diagnosis, sex, race, anatomic location of the injury, the use of alcohol, and association with a gunshot wound. Results There were an estimated 38,308 visits with an average age of 40.0 years (range, 1–83 years). The patients were predominantly male (93.3%), white (99.1%), and seen at small- or medium-size hospitals (80.6%). Disposition from the ED was admission in 20.1% and released in 79.9%. A fall occurred in 80.3%, a gunshot wound in 0.4%, and alcohol was involved in 0.6%. The most common diagnoses were a fracture (34.7%), contusion or abrasion (24.0%), strain or sprain (16.8%), laceration (7.7%), and internal organ injury (5.4%). Those injured in a fall were more frequently admitted (23.0% vs. 8.7%) and more likely to have a fracture (37.9% vs. 9.1%). Those with a fracture were older (44.6% vs. 37.9%). Those with internal organ injuries were more frequently admitted (44.8% vs 18.6%). Conclusions This study has characterized the epidemiology of hunting stand injuries with most occurring from falls. A fracture was the most common injury with a very low alcohol intoxication rate. These baseline data can now be used to compare other studies of hunting stand injuries and guide prevention strategies, such as education regarding the need for safety measures to prevent falls.
VISCERAL HELMINTH COMMUNITIES OF AN INSULAR POPULATION OF FERAL SWINE

Nine species of helminths, all nematodes, were recovered from the viscera of 48 feral swine (Sus scrofa) from Cumberland Island, Georgia. Both the overdispersed frequency distributions and the abundances of the four common species of helminths (Stephanurus dentatus, Metastrongylus apri, M. pudendotectus and Gongylonema pulchrum) did not vary significantly across the main and interactive effects of host sex and/or seasons. Whether or not the present low population densities of feral swine on Cumberland Island has influenced the pattern of fluctuations in abundances of helminth species across seasons as often observed in helminth communities from other hosts was not resolved. The apparent recent decline in prevalences and abundances, and the loss of certain species from the helminth communities of feral swine on the island may be explained partially by the decreasing transmission potentials of direct life cycle species caused by a recent marked reduction of numbers of individuals in the host population. Con...
Effect on Physician-Scientists of the Low Funding Rate of NIH Grant Applications

The threat to the future of the physician-scientist is currently the focus of considerable attention. Addresses to the scientific community and articles in the medical press frequently express concern over projected shortages in the number of physicians going into biomedical research and emphasize the need for organizations of physician-scientists to reverse this trend by promoting biomedical research as a national priority.1 2 3 4 5 The future of physician-scientists will ultimately depend on the existence of a funding system for biomedical research that provides medical schools with incentives to hire new physician-scientists and that ensures prospective physician-scientists of a reasonable chance of secure long-term . . .
Aspects of the Ecology of an Invasive Plant, Garlic Mustard (Alliaria petiolata), in Central Illinois

Alliaria petiolata (garlic mustard), an exotic plant species, has invaded woodlands in several areas in mid-western and northeastern United States and adjacent Canada, and it is displacing the indigenous under-story flora. This study was conducted to provide information about the species' biology that might be useful in controlling its spread in native woodlands. The plant is a strict biennial in North America, spending the first year of growth as a basal rosette. This period of relatively slow growth is followed by a period of rapid shoot elongation (1.9 cm/day) during early spring of the second growing season. The plant is capable of cross- and self-pollination, although pollination and stigma receptivity occur before the flower is open, so autogamy is the most likely breeding system. Garlic mustard invests 20.4% of its biomass in reproductive effort, with an annual seed rain of 15,000 seeds/m2. Seed dispersal from fruits begins in early July and continues into October. Most seeds germinate in the spring following the year in which they were produced. Seedling recruitment is high (8.3–18.0 seedlings/cm2), but only about 7.5% of the plants survive to maturity. The success of the plant in invading woodlands appears to be related to (1) its autogamous breeding system that allows a single individual, or a few individuals, to establish populations of genetically similar but interfertile individuals; (2) high seed production, permitting establishment of large numbers of individuals; and (3) rapid growth during the second growing season, which increases its competitive ability. Because of garlic mustard's ability to occupy understory habitats successfully, it may be unrealistic to expect to eliminate the plant from many habitats it has already invaded.
Stability analysis of a viscoelastic model for ion-irradiated silicon

Recently, elastic stress has been among several mechanisms hypothesized to induce the formation of ordered structures in Si irradiated at normal incidence by energetic ions. To test this hypothesis, we model the thin amorphous film atop ion-irradiated Si as a viscoelastic continuum into which the ion beam continually injects biaxial compressive stress. We find that at normal incidence, the model predicts a steady compressive stress of a magnitude comparable to experiment and molecular dynamics simulation. However, linear stability analysis at normal incidence reveals that this mechanism of stress generation is unconditionally stabilizing due to a purely kinematic material flow, depending on none of the material parameters. Thus, despite plausible conjectures in the literature as to its potential role in pattern formation, we conclude that compressive stress induced by normal-incidence ion bombardment is unlikely to be a source of instability at any energy. In fact, with this result, all hypothesized mechanisms suggested to explain structures on pure materials under normal incidence irradiation have now been overturned, supporting recent theories attributing hexagonal ordered dots to the effects of composition. In addition to this result, we find that the elastic moduli appear in neither the steady film stress nor the leading-order smoothening, suggesting that the primary effects of stress can be captured even if elasticity is neglected. This supports the basic framework recently adopted by other authors and should allow future analytical studies of highly nonplanar surface evolution, in which the beam-injected stress is considered to be an important effect.
Introduction to this special issue on human-robot interaction

(2004). Introduction to This Special Issue on Human-Robot Interaction. Human–Computer Interaction: Vol. 19, Human-Robot Interaction, pp. 1-8.
Falsely elevated plasma parathyroid hormone level mimicking tertiary hyperparathyroidism.

ABSTRACT Objective To report a case of misdiagnosed tertiary hyperparathyroidism attributable to heterophile antibody interference in a parathyroid hormone (PTH) assay. Methods We present clinical and laboratory data relative to this case and review the pertinent English-language literature. Results A 36-year-old woman with a functioning renal allograft, PTH excess (3, 374 pg/mL) refractory to medical therapy, and a history of renal osteodystrophy presented for consideration of a third parathyroidectomy. Remedial parathyroidectomy was performed. The PTH levels did not decline postoperatively, but the patient developed severe hypocalcemia. Reanalysis of the patient’s serum specimens was performed with (1) addition of heterophile blocking agents to the murine-based immunoassay and (2) use of a different, goat antibody-based immunoassay. The true PTH level was found to be 5 pg/mL with use of both methods. Conclusion Previous administration of muromonab-CD3 (Orthoclone OKT3) for immunosuppression may have resulted in the development of human antimurine heterophile antibodies, causing a falsely elevated PTH result. (Endocr Pract. 2011;17:e8-e11)
Decision Making in a Standby Service System

A standby service option allows a firm to lower its risk of not having sufficient capacity to satisfy demand without investing in additional capacity. Standby service options currently exist in the natural gas, electric, and water utility industries. Firms seeking standby service are typically large industrial or institutional organizations that, due to unexpectedly high demand or interruptions in their own supply system, look to a public utility to supplement their requirements. Typically, the firm pays the utility a reservation fee based on a nominated volume and a consumption charge based on the volume actually taken. In this paper, a single-period model is developed and optimized with respect to the amount of standby capacity a firm should reserve. Expressions for the mean and variance of the supplier's aggregate standby demand distribution are developed. A procedure for computing the level of capacity needed to safely meet its standby obligations is presented. Numerical results suggest that the standby supplier can safely meet its standby demand with a capacity that is generally between 20 to 50% of the aggregate nominated volume.
Noise Spectra and Directivity for a Scale-Model Landing Gear

An extensive experimental study has been conducted to acquire detailed noise spectra and directivity data for a high-fidelity, 6.3%-scale, Boeing 777 main landing gear. The measurements were conducted in the NASA Langley Quiet Flow Facility using a 41-microphone directional array system positioned at a range of polar and azimuthal observer angles with respect to the model. DAMAS (Deconvolution Approach for the Mapping of Acoustic Sources) array processing as well as straightforward individual microphone processing were employed to compile unique flyover and sideline directivity databases for a range of freestream Mach numbers (0.11 - 0.17) covering typical approach conditions. Comprehensive corrections were applied to the test data to account for shear layer ray path and amplitude variations. This allowed proper beamforming at different measurement orientations, as well as directivity presentation in free-field emission coordinates. Four different configurations of the landing gear were tested: a baseline configuration with and without an attached side door, and a noise reduction concept "toboggan" truck fairing with and without side door. DAMAS noise source distributions were determined. Spectral analyses demonstrated that individual microphones could establish model spectra. This finding permitted the determination of unique, spatially-detailed directivity contours of spectral band levels over a hemispherical surface. Spectral scaling for the baseline model confirmed that the acoustic intensity scaled with the expected sixth-power of the Mach number. Finally, comparison of spectra and directivity between the baseline gear and the gear with an attached toboggan indicated that the toboggan fairing may be of some value in reducing gear noise over particular frequency ranges.
Specific receptor for Escherichia coli heat‐stable enterotoxin (STa) may determine susceptibility of piglets to diarrheal disease

We have demonstrated the existence of a receptor that is specific for the Escherichia coli heat-stable enterotoxin (STa) on piglet's small intestine. The binding of STa to this receptor seemed specific, saturable and reversible. The receptor was demonstrated on brush border cells and membranes prepared from all of the piglets (n = 24) that developed clinical diarrhea when challenged with purified STa enterotoxin at the dose of 100 μg/kg body weight. The receptor was not demonstrated on intestinal brush border cells and membrane prepared from piglets (n = 3) that were refractory to the experimental induction of diarrhea. The data suggest that binding of the STa to a specific receptor on the small intestine of piglets is a prerequisite to the diarrheal response triggered by this toxin.
Surprising features of particle dynamics in channel-facilitated transport

ABSTRACT We analyze the consequences of interac tions between the pore and the transloca ting molecule within the framework of a continuous diffusion model using the Smoluchowski equati on with the radiation boundary conditions. We describe the solute-pore interaction in terms of the potential of mean force. Several of our analytical findings are quite counter-intuitive. Three of the examples to be discussed here are: (i) Sticking to the channel slows down translocation (a particle spends more time in the channel) but increases the flux; (ii) If the potential well modeling the particle-channel interaction occupies only a part of the channel length, the average translocation time is non-monotonic in the width of the potential well, first increasing and then decreasing; (iii) At a finite potential bias applied to the channel, the mean up-hill and downhill particle translocation times (and their distributions) are identical. Keywords: Diffusion, Smoluchowski equation, membrane transport
Energy Velocity in Negative Group Index Structures

Energy velocity in negative group index structures is investigated. It is shown that the negative group index phenomenon is an exhibition of effective negative index-of-refraction while the group velocity still equals the energy velocity.
Caldesmon tethers myosin V to actin and facilitates in vitro motility.

The current study examines the hypothesis that caldesmon can facilitate the interaction of myosin V with actin filaments by tethering myosin V to actin. Myosin V, purified from bovine brain stem, translocated actin filaments in an in vitro motility assay at a velocity of 0.30 ± 0.05 μm/s in the absence of caldesmon at a myosin concentration of 50 μg/ml (ionic strength=110 mM). Filament binding and motility was absent when the myosin concentration applied to the coverslip was reduced to 5 μg/ml, however, the addition of 0.4μM caldesmon restored binding and motility (0.28 ± 0.06 μm/s). This restoration of motility in the presence of caldesmon was blocked by an N-terminal fragment of caldesmon that competitively inhibits the binding of intact caldesmon to myosin. Similar to previous findings with both smooth muscle myosin and platelets (Haeberle et al., 1992; Hemric et al., 1994), these results demonstrate that caldesmon can form a mobile tether that maintains the proximity of myosin V with actin filaments without restricting filament sliding.
The Impact of Mobile Technologies on Distance Education

This article considers the growing amount of research on using mobile technologies in education. As mobile devices become increasingly more prevalent, it is imperative to study their use and effect on the growing field of distance education. This brief review of existing literature indicates that traditional theories of learning, in both traditional and distance settings, are relevant and applicable to mobile learning, and that mobile devices can be brought thoughtfully into pedagogy at the distance level. Flexibility, portability, and accessibility contribute to an overall positive impression on students, while faculty concerns can be met with appropriate training and tailoring to the various teaching and learning styles present in distance education. Student and faculty expectations of a mobile-integrated distance education experience will continue to grow, while teaching and learning should thrive in this increasingly more connected environment.
Toughness scale from first principles

We correlate the experimentally measured fracture toughness of 24 metals and ceramics to their quantum mechanically calculated brittleness parameter. The brittleness parameter is defined as the ratio of the elastic energy density needed to spontaneously break bonds in shear versus in tension, and is a primitive-cell property. Under 300 GPa hydrostatic pressure, the model predicts that diamond has smaller brittleness than molybdenum at zero pressure, and thus should deform plastically without cracking at room temperature.
Strategies to Improve Insulin Adherence in Adolescents With Type 1 Diabetes

The Pediatric Endocrinology Nursing Society (PENS) is committed to the development and advancement of nurses in the art and science of pediatric endocrinology nursing and to improve the care of all children with endocrine disorders through the education of the pediatric Type 1 diabetes (T1DM) is a serious health condition with the potential for significant morbidity and mortality, and economic burden (Stanger et al., 2013). Poor medication adherence is a common problem in adolescents with a chronic health condition, resulting in adverse health outcomes (Dean, Walters, & Hall, 2010; Hanghoj & Boisen, 2014). Medication adherence is crucial to survival for the T1DM adolescent and is an important aspect of care to minimize long-term complications. According to the Centers for Disease Control and Prevention, the incidence of T1DM in adolescents ages 12 to 19 is approximately 1 in 500, with significantly poorer adherence to medication than in adults (Stanger et al., 2013). Adherence is defined as the extent with which a person follows recommendations from the health care provider, and medication adherence is defined as the extent with which a person takes medications as prescribed by the health care practitioner (Dean et al., 2010). Evidence from the pivotal Diabetes Control and Complications Study documents the association between intensive insulin management and good glycemic control (Hood, Peterson, Rohan, & Drotar, 2009). However, the process is difficult for most adolescents, due in part to the changing insulin requirements as a result of puberty and insulin resistance in adolescence, but more importantly due to “the imperfect nature of the treatment regimen, and psychosocial variables” producing a negative effect upon glycemic control (Hood et al., 2009, p. e1172).
Bioaffinity limitations for anisotropically etched silicon microfluidics

Immobilisation of biological specimens is an essential process in biomicrofluidics for micro total analysis systems (μTASs) applications, to carry out high throughput bioassays. Closed microfluidic channels restrict immobilisation feasibilities to only direct conjugation of the biomolecules with the channel surface through appropriate flow control-based incubation techniques. In this work, the limitations of bioaffinity on anisotropically etched silicon microfluidic channels have been studied. The flow behaviour within the microchannels has been analysed by solving the Navier-Stokes equation using finite element method (FEM). The results have been used to predict the immobilisation and rinsing behaviour within anisotropically etched trapezoidal and triangular microfluidic channels.
Modeling of axially symmetric flow reactors

Abstract A method of calculating the velocity profiles and species concentrations in axially symmetric flow reactors is presented. The method is illustrated with a reactor consisting of three concentric tubes arranged so that reactants flow through the inner tube and inner annulus to a mixing region and the products flow out through the outer annulus. A single bimolecular reaction is used in the example. The method involves two steps; calculation of the velocity field from a solution of the Navier-Stokes equations, followed by solution of the species conservation equations. The technique provides a way of analyzing reactors with variable cross sections and sampling ports near mixing regions.
Community-acquired pneumonia

This seminar reviews important features and management issues of community-acquired pneumonia (CAP) that are especially relevant to immunocompetent adults in light of new information about cause, clinical course, diagnostic testing, treatment, and prevention. Streptococcus pneumoniae remains the most important pathogen; however, emerging resistance of this organism to antimicrobial agents has affected empirical treatment of CAP. Atypical pathogens have been quite commonly identified in several prospective studies. The clinical significance of these pathogens (with the exception of Legionella spp) is not clear, partly because of the lack of rapid, standardised tests. Diagnostic evaluation of CAP is important for appropriate assessment of severity of illness and for establishment of the causative agent in the disease. Until better rapid diagnostic methods are developed, most patients will be treated empirically. Antimicrobials continue to be the mainstay of treatment, and decisions about specific agents are guided by several considerations that include spectrum of activity, and pharmacokinetic and pharmacodynamic principles. Several factors have been shown to be associated with a beneficial clinical outcome in patients with CAP. These factors include administration of antimicrobials in a timely manner, choice of antibiotic therapy, and the use of a critical pneumonia pathway. The appropriate use of vaccines against pneumococcal disease and influenza should be encouraged. Several guidelines for management of CAP have recently been published, the recommendations of which are reviewed.
Is prompt exploratory laparotomy the best attitude for mesenteric ischemia after cardiac surgery

Mesenteric ischemia following cardiac surgery is a life-threatening complication. Early identification of patients may help optimizing management and improving outcome. Between January 2000 and July 2007, surgical exploration was realized when mesenteric ischemia was suspected after coronary-artery bypass grafts (CABG). Patients were divided in two groups according to diagnosis confirmation upon laparotomy. Peri-operative predictors of complication and death were analyzed. Of 1634 consecutive patients, 13 (0.8%) developed acute abdomen with suspicion of mesenteric ischemia. Seven (0.4%) underwent resection for ischemic lesions (group 1), of whom two were during a second look laparotomy. The other six patients had normal bowel (group 2). Both groups were comparable according to preoperative status, clinical signs, biological and radiological findings. Delays to laparotomy were 13.7+/-19.0 and 51.4+/-29.0 h in group 1 and 2, respectively (P=0.02). Mortality rates were 46.1% (6/13) overall, 42.8% for group 1 and 50% for group 2. All deaths occurred within the first nine postoperative days. Mesenteric ischemia following CABG is a fatal complication in almost half the cases. Diagnostic tools and timely laparotomy still need to be optimized. Low threshold-based strategy for prompt surgical intervention is efficient for both diagnosis and treatment.
An electron microscopy examination of primary recrystallization in TD-nickel

Primary recrystallization in TD-nickel 1 in. bar has previously been regarded as the process by which the initial fine grain structure (1μ average grain radius) is converted to a coarse grain size (increases in grain size by 500 times) under suitable deformation and annealing conditions. This process is dependent on deformation mode. While it occurs readily after rolling transverse to the bar axis and annealing (800°C), it is completely inhibited by longitudinal rolling and swaging deformations, even for very high (1320°C) annealing temperatures. A transmission electron microscopy examination of deformation and annealing substructures indicates that primary recrystallization in TD-nickel 1 in. bar actually occurs on the sub-light optical level, to produce a grain structure similar in size to the initial fine grained state. Coarse grain formation is the result of abnormal grain growth (or secondary recrystallization), which follows primary recrystallization.
Business as Usual? An Exploration of the Deteriminants of Success in the Multinational Transfer of Corporate Responsibility Initiatives

We conduct an exploratory study of the determinants of success in the multinational transfer of social practices. We find that though extant literature on business practice transfer provides some relevant insight, social practice transfer differs in significant ways from "business as usual." In particular, successful social practice transfer is associated not with concrete and clearly codified initiatives, but with ambiguous and loosely bounded initiatives; not with management by business units that have mastered internal organizational dynamics, but with those that focus on understanding external stakeholder needs; not with maintaining complete control over the transfer process, but with opening it up to substantive stakeholder involvement. We discuss the implications of our findings for development of a more nuanced view of how to manage social practices within multinationals.
Oxygen Barrier Properties of Copolyesters Containing a Mesogenic Monomer

Thermal properties and solid-state structure of copolyesters based on smectic poly(diethylene glycol 4,4‘-bibenzoate) (PDEGBB) and non-liquid crystalline poly(diethylene glycol isophthalate) (PDEGI) were characterized previously. The present study examined the oxygen transport properties and free volume characteristics of quenched films with 10−50 mol % isophthalate. Isophthalate was not accommodated in the smectic lattice; as a result, copolymerization effectively disrupted the LC character. The estimated smectic volume fraction of PDEGBB was 0.84. Copolymerization with 10 and 20 mol % isophthalate decreased the smectic fraction to 0.59 and 0.16, respectively. The copolymer with 30 mol % isophthalate did not exhibit any LC character. Decreasing density and increasing free volume hole size accompanied the loss of LC features. Oxygen permeability also increased due to increases in both solubility and diffusivity. Oxygen solubility of LC glasses conformed to a two-phase model consisting of a less permeable ...
Urinary excretion of cyclic nucleotides and phosphate in response to parathyroid hormone and calcitonin in man.

Summary: The response to parathyroid hormone (PTH) and calcitonin (CT) was studied in eight children with various bone diseases by determining the serum calcium (Ca) and phosphate (P) concentration, urinary phosphate excretion rate, renal phosphate clearance, the percentage of filtered phosphate reabsorbed by the renal tubule (%TRP), creatinine clearance (Ccr), urinary cyclic adenosine 3′,5′ monophosphate excretion rate (UcAMPV), and urinary cyclic guanosine 3′,5′ monophosphate excretion rate (UcGMPV). Administration of PTH caused no significant change in serum Ca and P values, whereas CT produced a decrease in Ca (Δ Ca, −1.4 ± 0.1 mg/100 ml) and P (ΔP; −1.1 ± 0.1 mg/100 ml). There was an increase in UcAMPV (ΔUcAMPV; 437 ± 74 nmoles/min/100 ml Ccr) without any significant change in UcGMPV after administration of PTH. Phosphaturia was produced by both PTH (Δ TRP, −18 ± 3%) and CT (ΔTRP, −13 ± 2%). However, CT did not elicit any increase in either UcAMPV or UcGMPV. Speculation: Parathyroid hormone (PTH) and calcitonin (CT) induce phosphaturia of a similar magnitude whereas PTH alone increased the urinary excretion of cyclic adenosine 3′,5′ monosphosphate (cAMP). The phosphaturia induced by CT may not be mediated by a similar mechanism involving the adenylate cyclase-cAMP system as demonstrated for PTH.
Isolation of partial complementary DNA encoding human thromboxane synthase

Thromboxane synthase catalyzes the biosynthesis of thromboxane A2 which plays a key role in the proaggregatory and vasoconstrictive processes. In this communication, we reported the successful cloning of thromboxane synthase cDNA from a human lung cDNA library. Oligonucleotides were synthesized according to the direct amino acid sequence of 2 peptides derived from purified human thromboxane synthase. Polymerase chain reaction was carried out using these oligonucleotides as primers to isolate a complementary DNA from human lung cDNA library. The longest cDNA thus obtained was 687 base pairs in length. Amino acid sequences deduced from the cDNA contained all three peptide sequences reported, confirming the authenticity of the cDNA clone.