cssi/SciSciGPT-SciSciNet huggingface dataset:
Hierarchical patterns of symbiotic orchid germination linked to adult proximity and environmental gradients

Summary 1 The recruitment stage can be critical in determining plant population dynamics, as juveniles encounter a range of abiotic and biotic stressors in the environments where they land after dispersal, and often experience high mortality rates. Although both abiotic and biotic constraints on recruitment are often assumed to operate at multiple scales, these relationships are rarely quantified in ways that enable prediction of recruitment dynamics across environmental gradients. 2 In plants such as orchids, an important bottleneck on recruitment may arise from an obligate dependence on mycorrhizal fungi in order to reach photosynthetic stage. Very little is known, however, about the factors controlling the distribution of the fungi or how fungal distributions may constrain orchid recruitment and distributions. 3 In this study, seed introduction experiments were used to test for relationships between symbiotic germination success of an orchid, Goodyera pubescens, and both proximity to adult orchids and soil abiotic conditions. Experiments were linked to ongoing demographic monitoring across a large environmental gradient to place patterns of germination better in the context of longer-term demographic patterns. 4 A hierarchical Bayesian statistical framework was used to evaluate explicitly how recruitment varies across scales and how this variation is explained by key abiotic variables. This framework was further utilized to link hypothesis testing to model building, and thereby improve our ability to make predictions across a range of environmental conditions. 5 At a microsite scale (< 4 m2) strong evidence was found for decreasing germination success further from adult plants. At distances greater than 1 m from adults, increased germination success was associated with higher soil moisture, higher organic content and lower pH, although the strength of these relationships varied regionally. Patterns of symbiotic germination success were also highly correlated with observed recruitment patterns at the population level. 6 Explicitly linking plant recruitment to underlying abiotic gradients and key biotic interactions using a hierarchical, predictive modelling framework is essential for understanding basic plant population processes and building capacity to make predictions of how species and communities may respond to environmental changes.
Electrospun polydioxanone–elastin blends: potential for bioresorbable vascular grafts*

An electrospun cardiovascular graft composed of polydioxanone (PDO) and elastin has been designed and fabricated with mechanical properties to more closely match those of native arterial tissue, while remaining conducive to tissue regeneration. PDO was chosen to provide mechanical integrity to the prosthetic, while elastin provides elasticity and bioactivity (to promote regeneration in vitro/in situ). It is the elastic nature of elastin that dominates the low-strain mechanical response of the vessel to blood flow and prevents pulsatile energy from being dissipated as heat. Uniaxial tensile and suture retention tests were performed on the electrospun grafts to demonstrate the similarities of the mechanical properties between the grafts and native vessel. Dynamic compliance measurements produced values that ranged from 1.2 to 5.6%/100 mmHg for a set of three different mean arterial pressures. Results showed the 50:50 ratio to closely mimic the compliance of native femoral artery, while grafts that contained less elastin exceeded the suture retention strength of native vessel. Preliminary cell culture studies showed the elastin-containing grafts to be bioactive as cells migrated through their full thickness within 7 days, but failed to migrate into pure PDO scaffolds. Electrospinning of the PDO and elastin-blended composite into a conduit for use as a small diameter vascular graft has extreme potential and warrants further investigation as it thus far compares favorably to native vessel.
Audio Frequency Dsp Laboratory On A Chip - TMS32010

Various applications of the TMS32010 as an audio signal processing system are discussed. Although this chip is a first generation part, it contains most of the architecture necessary for real time DSP in the audio frequency range. A number of experiments that can be performed with a minimum of hardware are described. Included are spectrum shifting, digital filters, spectrum analysis, and adaptive filters. This material should be useful to independent research groups and universities embarking on new DSP programs.
Photoionization threshold measurements for CF2 loss from perfluoropropylene, perfluorocyclopropane, and trifluoromethylbenzene. The heat of formation of CF2 and consideration of the potential-energy surface for interconversion of isomeric C3F6 neutrals and ions☆

Abstract Photoionization of perfluoropropylene, perfluorocyclopropane, and trifluoromethylbenzene yields onsets for production of ions formed by loss of a CF 2 neutral fragment. A value Δ H f 298 o , (CF 2 ) = —44.2 ± 1 kcal mol −1 is derived from these thresholds. Earlier determinations of Δ H f 298 o (CF 2 ) are re-interpreted using updated thermochemical values and found to be in excellent agreement with this value. The heat of formation of neutral perfluorocyclopropane, Δ H f 298 o (c-C 3 F 6 = —233.8 ± 2 kcal mol −1 , is derived from the onset for C 2 F 4 + production and the Δ H f o (CF 2 ) value cited. This compares favorably with the heat of formation of perfluorocyclopropane derived from measurements of the forward and reverse enthalpies of activation for the addition of CF 2 to C 2 F 4 . The energetics of the interconversion of perfluoropropylene and perfluorocyclopropane are described both for the neutral species and their molecular ions.
On Mentally Mapping Greater Asante: A Study Of Time And Motion

This paper examines the way in which Greater Asante was ‘mentally mapped’, thereby enabling government to regulate the movement of couriers, and others, along the great-roads. Lacking clocks, speed was reckoned anthropometrically, by reference to dɔn: rhythmic walking at a normal pace. Computing this against the determinate parts of the day, from dawn to dusk, on which travel (as opposed to eating and resting) was customary, it became possible to estimate the location of a courier at a given point in time. Greater Asante was ‘mapped’ as a circle, the diameter of which was the Asante month of forty-two days (of travel). The circle embraced the most distant of the territories over which the Asantehene claimed authority; these were in fact more or less twenty days from the capital. That it also embraced, in the south, lands under the sea, was of no practical relevance. Superimposing the reckoning of travel times on the matrix of the forty-two days ‘imperium’, the Asante government was able to establish a (‘Monday’) timetable for the conduct of business. The record shows that it worked remarkably well. An understanding of ‘traditional’ practices and procedures has much importance for the understanding of ‘modern’ ones: the past is encapsulated in the present.
Kinetics of Interaction of the Myristoylated Alanine-rich C Kinase Substrate, Membranes, and Calmodulin

Membrane binding of the myristoylated alanine-rich C kinase substrate (MARCKS) requires both its myristate chain and basic "effector" region. Previous studies with a peptide corresponding to the effector region, MARCKS-(151-175), showed that the 13 basic residues interact electrostatically with acidic lipids and that the 5 hydrophobic phenylalanine residues penetrate the polar head group region of the bilayer. Here we describe the kinetics of the membrane binding of fluorescent (acrylodan-labeled) peptides measured with a stopped-flow technique. Even though the peptide penetrates the polar head group region, the association of MARCKS-(151-175) with membranes is extremely rapid; association occurs with a diffusion-limited association rate constant. For example, kon = 10(11) M-1 s-1 for the peptide binding to 100-nm diameter phospholipid vesicles. As expected theoretically, kon is independent of factors that affect the molar partition coefficient, such as the mole fraction of acidic lipid in the vesicle and the salt concentration. The dissociation rate constant (koff) is approximately 10 s-1 (lifetime = 0.1 s) for vesicles with 10% acidic lipid in 100 mM KCl. Ca2+-calmodulin (Ca2+.CaM) decreases markedly the lifetime of the peptide on vesicles, e.g. from 0.1 to 0.01 s in the presence of 5 micrM Ca2+.CaM. Our results suggest that Ca2+.CaM collides with the membrane-bound MARCKS-(151-175) peptide and pulls the peptide off rapidly. We discuss the biological implications of this switch mechanism, speculating that an increase in the level of Ca2+-calmodulin could rapidly release phosphatidylinositol 4, 5-bisphosphate that previous work has suggested is sequestered in lateral domains formed by MARCKS and MARCKS-(151-175).
The potential benefit of 6 vs. 3 cycles of chemotherapy in subsets of women with early-stage high-risk epithelial ovarian cancer: An exploratory analysis of a Gynecologic Oncology Group study

Abstract Objectives A prior clinical trial on early-stage high risk ovarian cancer showed a lower recurrence rate in those treated with six vs. three cycles of chemotherapy. We proposed to identify subsets of patients who may benefit from more cycles of chemotherapy. Methods Outcomes of patients who underwent six vs. three cycles of chemotherapy were analyzed based on clinico-pathologic factors. Kaplan–Meier estimates and Cox Regression Model were used for analyses. Results Of 427 patients (median age: 55 years), 69% had stage I disease, 30% had clear cell, 25% endometrioid, 23% serous, 7% mucinous, and 15% had other cell types. The risk of recurrence in those who had six vs. three cycles of chemotherapy was not different based on age, performance status, stage, grade of disease, presence of ascites, tumor rupture, or positive cytology. However, those with serous tumors had a significantly lower risk of recurrence after six vs. three cycles of chemotherapy (HR=0.33, CI=0.14–0.77; p =0.04) in contrast to non-serous tumors (HR=0.94, CI=0.60–1.49). Nevertheless, a test of homogeneity did not show a difference in treatment effects across cell types ( p =0.285). Of those with serous tumors, the 5-year recurrence-free survival was 83% and 60% in those who received six vs. three cycles of chemotherapy, respectively ( p =0.007). Conclusions In this exploratory analysis of early-stage high risk ovarian cancer, our data suggest that six rather than three cycles of chemotherapy may decrease the recurrence of patients with serous tumors. Further studies are needed to confirm these findings.
Capital punishment and public opinion in the post‐Furman era: Trends and analyses

An analysis of public opinion polls shows a pronounced trend of increased support for the use of capital punishment since this sanction's ban and subsequent reinstatement in the 1970s. This support is frequently cited in political arenas as justification for the retention of this criminal justice practice despite its rejection by virtually all other culturally and economically similar societies. However, further examination of data from the General Social Surveys reveals that this trend is best understood in terms of a solidifying of support for capital punishment among whites, whose expressed approval is now nearly uniform across sociodemographic categories and has reached unprecedented heights during the late 1980s. Reasons for the racial nature of support for capital punishment are explored, and new areas of research are suggested as avenues of gaining further insight into the continuation of what has become a particularly unique criminal justice policy.
Effect of calcium and phosphate on bicarbonate and fluid transport by proximal tubules in vitro.

Effect of calcium and phosphate on bicarbonate and fluid transport by proximal tubules in vitro. Previous studies in living animals have suggested that variations in the serum concentrations of calcium and phosphate directly affect renal tubular bicarbonate transport. To examine this area more directly, we measured the bicarbonate and the fluid transport in isolated rabbit proximal convoluted and straight tubules perfused in vitro. The concentration of calcium in the perfusate was varied between 0 and 5mM and in the bath between 0.5 and 5mM. In proximal convoluted tubules, 5mM calcium in the perfusate and bath caused a significant increase in the rate of bicarbonate absorption, and removal of calcium from the perfusate inhibited both bicarbonate and fluid absorption. The concentration of phosphate in the perfusate and the bath was varied from 0.25 to 5mM. In both convoluted and straight tubules, there was no significant change in bicarbonate or fluid absorption with changes in the ambient phosphate concentration. We conclude that changes in calcium concentration have significant effects on bicarbonate transport by proximal convoluted tubules but that wide variations in the concentration of phosphate have no significant effect on bicarbonate, sodium, or fluid transport by proximal tubules in vitro. Effet du calcium et du phosphate sur le transport de bicarbonate et d'eau par les tubes proximaux in vitro. Des etudes anterieures in vivo ont suggere que les modifications des concentrations plasmatiques de calcium et de phosphate affectent directement le transport tubulaire du bicarbonate. Afin d'etudier ce probleme plus directement, le transport de bicarbonate et d'eau a ete mesure dans des tubes contournes proximaux et des tubes droits de lapin isoles perfuses in vitro. La concentration de calcium dans le perfusat a varie de 0 a 5mM et dans le bain de 0,5 a 5mM. Dans le tube contourne proximal une concentration de 5mM de calcium dans le perfusat et dans le bain a determine une augmentation significative du debit de reabsorption de bicarbonate et la suppression du calcium dans le perfusat a inhibe a la fois la reabsorption de bicarbonate et la reabsorption d'eau. La concentration de phosphate dans le perfusat et le bain a ete variee de 0,25 a 5mM. Aussi bien dans le tube contourne proximal que dans le tube droit il n'y a pas eu de modifications significatives dans l'absorption de bicarbonate ou d'eau liees a des modifications de la concentration ambiante de phosphate. Nous concluons que les modifications de la concentration de calcium ont des effets significatifs, sur le transport de bicarbonate par le tube contourne proximal mais que des variations importantes de la concentration de phosphate n'ont pas d'effet significatif sur le transport de bicarbonate de sodium ou d'eau par les tubes proximaux in vitro.
Stable Galerkin reduced order models for linearized compressible flow

The Galerkin projection procedure for construction of reduced order models of compressible flow is examined as an alternative discretization of the governing differential equations. The numerical stability of Galerkin models is shown to depend on the choice of inner product for the projection. For the linearized Euler equations, a symmetry transformation leads to a stable formulation for the inner product. Boundary conditions for compressible flow that preserve stability of the reduced order model are constructed. Preservation of stability for the discrete implementation of the Galerkin projection is made possible using a piecewise-smooth finite element basis. Stability of the reduced order model using this approach is demonstrated on several model problems, where a suitable approximation basis is generated using proper orthogonal decomposition of a transient computational fluid dynamics simulation.
Speech criticism effectiveness: A classification and suggestions for future research

This essay suggests there is a need to identify and integrate into one coherent perspective feedback variables associated with research on speech criticism effectiveness. It is suggested that these variables can be viewed as hierarchal levels to be either controlled or manipulated. Some research designs that emanate from this classification are suggested.
The Effects of Communication Apprehension on Interpersonal Attraction

Two studies are reported which indicate that high communication apprehensives are perceived as less interpersonally attractive than low communication apprehensives by members of the opposite sex. Effects of physical appearance and attitude similarity on interpersonal attraction, consistent with previous research, were also observed. It was also found that, in general, the more communication apprehensive the subject the less the subject was attracted to other people.
Reactions of metallocenes with potassium and potassium amide in liquid ammonia

Abstract Both (C 5 H 5 ) 2 Fe and (C 5 H 5 ) 2 Ni are soluble in liquid ammonia at −33·5° but show no evidence of formation of stable ammoniates; (C 5 H 5 ) 2 Cr however forms 9- and 4-ammoniates. Both (C 5 H 5 ) 2 Fe and (C 5 H 5 ) 2 Ni are unreactive toward ammonia solutions of potassium amide at −33·5°; (C 5 H 5 ) 2 Cr reacts to form CrN. All three metallocenes are reduced to the metals by solutions of potassium in ammonia at −33·5° without evidence for reduction to species in which the metal is in the formal 1+ oxidation state. The validity of Fischer and Wilkinson's reported synthesis of (C 5 H 5 ) 2 Ti is questioned.
Using modeling knowledge to guide design space search

Automated search of a space of candidate designs is an attractive way to improve the traditional engineering design process. To make this approach work, however, an automated design system must include both knowledge of the modeling limitations of the method used to evaluate candidate designs and an effective way to use this knowledge to influence the search process. We argue that a productive approach is to include this knowledge by implementing a set of model constraint functions which measure how much each modeling assumption is violated. The search is then guided by using the values of these model constraint functions as constraint inputs to a standard constrained nonlinear optimization numerical method. A key result of our work is a successful demonstration of the application of AI techniques to an important engineering problem. In an empirical study of parametric conceptual aircraft design, we observed a cost improvement of two orders of magnitude. The principal contribution of our work is a new design optimization methodology which makes explicit the interaction between models of artifacts, and validity models of artifact models.
Growth of Rhododendron, Rudbeckia and Thujia and the Leaching of Nitrates as Affected by the pH of Potting Media Amended with Biosolids Compost

A conventional potting media containing peat moss, softwood bark and sand was amended to contain 0,25,50,75 and 100 (percent vol−1) municipal compost made from yard waste and biosolids. Each medium was adjusted with limestone and sulfur to an approximate pH of 5.0, 6.0 or 7.0. Rhododendron Panticum L. ‘Anah Kruschke’ (Rhododendron), Thujia occidentalis L. (Arborvitae) and Rudbeckia hirta L. ‘Goldilocks’ (Black-eyed Susan) were grown in each medium and pH level for 18 months. Leachate from pots was tested for NO3-N and NH3-N+NH4-N to determine how media pH and the amount of compost effected the potential for potting media to be a source of nitrate in surface and ground water.Media pH affected plant growth more than the percent compost. Compared to media with a pH of 7.0, statistically significant increases in the growth of Rhododendron occurred in media with a pH of 5.0 or 6.0. This pH effect was similar but less pronounced for Thujia. Growth of Rudbeckia was not effected by media pH or percent compost. Me...
Communication and consumer decision making about cancer clinical trials.

Abstract Communication between patients and physicians likely mediates traditional patient and physician predispositions in determining patient outcomes, including perceptions and decision making. However, the extent to which a mediating effect occurs is unclear. The purpose of this essay is to outline the need for conceptualizing more holistic models of consumer–provider interaction that demonstrate the role of the therapeutic relationship in treatment outcomes. We focus on an important communicative context for exploring this question: the situation where patients, with the help of oncologists, are faced with making treatment choices, particularly whether to enroll in a clinical trial in response to their life-threatening cancer diagnosis. We explore the question from the perspectives of the medical provider, the patient, and the accompanying family member, in order to better frame the complex interactional dynamics occurring during the interaction.
Computer instruction for scholars in the humanities

The common theme running through our discussion of both modes of adaptation to computer technology and problem areas in effective computer-assisted research is the relationship between computer expertise and scholarly research. Knowledge about computers is currently gained by social scientists and humanists in a wide variety of fashions. There are very few formal instructional programs, and most computer skills are obtained on the job. Although it is impossible at this stage to specify in detail either the content or the prerequisites for computer instructional programs for scholars in the social sciences and the humanities, I would recommend for consideration on the following general points. Investigators should have a basic understanding of the design and logic of computers. This knowledge will enable them to have a clearer concept of computers as symbol manipulating devices capable of both arithmetic and logical operations. However, very few investigators will ever use a computer at the level of its basic machine language. Therefore, investigators should learn to solve problems in higher level languages. I consider it essential that they learn at least two such languages, including both numerical and character manipulations. This kind of comprehensive instructional program will assist investigators in exercising greater control over the computer-assisted phases of research; it should allow them wider flexibility in selecting computer techniques appropriate for the research design; and finally, it will allow greater ease in adapting to future advances in computers.
The black addict: I.Methodology, chronology of addiction, and overview of the population.

One hundred ninety-two Black, male heroin addicts in various phases of treatment and nontreatment, including never-treated active addicts and actively addicted treatment dropouts, were systematically interviewed for early life events, psychosocial variables, and natural history of addiction. This report presents the chronology of the addiction problem from childhood as well as evidence of significant early antisocial activities predating drug use in this population. Data on family characteristics, arrests, problems in formal schooling, and adult activities are summarized. The current work is compared to earlier data on comparable populations.
Development of a Web-Based, Student-Centered Stereochemistry Tutorial

A Web-based stereochemistry tutorial is described that details the core definitions and structural representations of stereochemistry in an organic chemistry course. The Cahn–Ingold–Prelog rules and their application for assigning R and S orientations to stereocenters and E and Z orientations to alkenes are discussed. This tutorial is unique in allowing students to determine their preferred structural representation of organic molecules and select their own method for making stereochemical comparisons between these molecules. The remaining content of the comparison section of the tutorial is presented using the method that the student selected.
Absorption and Mobility of Foliar Applied Nutrients.

The absorption, transport and mobility of foliar applied radioactive isotopes of rubidium, sodium, potassium, phosphorus, chlorine, sulfur, zinc, copper, manganese, iron, molybdenum, calcium, strontium, and barium were determined with the bean as the experimental plant. Using as a criterion the percent of the foliar applied radioactive isotope recovered in non-treated plant parts, and autoradiography to portray gross distribution in the plant it was found that rubidium, sodium and potassium were the most readily absorbed and most highly mobile. Calcium, strontium and barium while absorbed by the leaf were not exported from the leaf and were considered immobile. Phosphorus, chlorine, sulfur, zinc, copper, manganese, iron, and molybdenum were intermediate with decreasing mobility in the order given. Since the preparation of this manuscript, preliminary observations with magnesium (Mg/sup 28/) showed that it was immobile and its distribution following foliar application was the same as Ca/sup 45/, Sr/sup 89/ or BaLa/sup 140/. 22 references, 4 figures, 4 tables.
Clinical nurse specialist practice domains and evidence-based practice competencies: a matrix of influence.

Purpose The purpose of this article is to describe master's-level evidence-based practice (EBP) competencies as determined by a national consensus panel and present an EBP matrix that illustrates the influence that the clinical nurse specialist (CNS) practice can have on driving EBP change. Background Evidence-based practice is a growing and necessary paradigm for nursing care. The ACE Star Model conceptualizes the knowledge transformation that must occur in an EBP environment as 5 distinct points: discovery, summary, translation, integration, and evaluation. Master's-level EBP competencies based on these 5 steps were established by a national consensus panel. The CNS's practice can be organized around 5 domains: expert practitioner, researcher, consultant, educator, and leader. The master's-level EBP competencies can be transposed on a crosswalk of the ACE Star Model and the 5 CNS practice domains to form a matrix representing the influence that CNSs can have over the EBP process. Implications Each competency falls well within the practice domains of the CNS, making the CNS an ideal person to lead the EBP movement forward, providing tangible outcomes to further demonstrate the need for the CNS role.
Thinking outside the box by looking inside the box: Extending the cognitive revolution in leadership research

Abstract Follower and leader cognitions play critical roles in many organizational phenomena. In this review, we report and reflect on a decade of cognitive leadership research. Following a brief introduction, the review is divided into two sections—one devoted to individual and dyadic cognition, and the other to collective cognition. We identified three central themes for each section. For individual and dyadic cognition, we identified metacognitive processes and leadership, implicit leadership theories (ILTs), and network based models of ILTs as central themes. For collective cognition, we identified charisma, organizational performance and sensemaking, and transformation and change as central themes. Our goal in this review was to uncover important underlying assumptions of selected studies to illuminate more clearly the path of cognitive leadership research over the past 10 years and its potential paths over the next ten years.
Effects of fuel reduction on birds in pitch pine–scrub oak barrens of the United States

Fire-dependent ecosystems include some of the most threatened ecosystems in the world, and where fuels are allowed to accumulate, they can present significant threats to human life and property. Fuel reduction activities can be effective in reducing the risk of wildfire, but these practices need to be evaluated relative to their effect on biodiversity. We surveyed birds in an inland pitch pine–scrub oak barren, a fire-dependent plant community, in which fuel reduction had been carried out via thinning of canopy trees to reduce the risk of running crown fires. We hypothesized that thinning pitch pine forest would negatively affect the abundance of mature forest birds and positively affect the abundance of scrub–shrub birds. Our results confirmed these expectations: several mature forest bird species were less abundant in thinned pitch pine than unthinned pitch pine, although most of these species were also present in mixed deciduous forest, and therefore regionally well represented. In contrast, another group of bird species was scarce or absent from unthinned pitch pine and mixed deciduous forest, but present in thinned sites and scrub oak stands. These were scrub–shrub species that do not nest in mixed deciduous or pitch pine forest but depend on shrubland or savannah habitats that cover ∼3% of the region. We conclude that fuel reduction by thinning canopy trees at this site provides habitat for high-priority scrub–shrub bird species at the cost of modest reductions in numbers of forest birds whose regional aggregate population is large.
Gangliosides help stabilize the brain

Defects in the breakdown of gangliosides are associated with a class of disorders known as lysosomal storage diseases. Now, a defect in the synthesis of gangliosides, glycolipids that contain sialic acid and are abundant in the brain, has been shown to underlie an inherited form of epilepsy.
Nested transactional memory: model and architecture sketches

We offer a reference model for nested transactions at the level of memory accesses, and sketch possible hardware architecture designs that implement that model. We describe both closed and open nesting. The model is abstract in that it does not relate to hardware, such as caches, but describes memory as seen by each transaction, memory access conflicts, and the effects of commits and aborts. The hardware sketches describe approaches to implementing the model using bounded size caches in a processor with overflows to memory. In addition to a model that will support concurrency within a transaction, we describe a simpler model that we call linear nesting. Linear nesting supports only a single thread of execution in a transaction nest, but may be easier to implement. While we hope that the model is a good target to which to compile transactions from source languages, the mapping from source constructs to nested transactional memory is beyond the scope of the paper.
Low on-resistance GaN pin rectifiers grown on 6H-SiC substrates

Low on-resistance gallium nitride pin rectifiers grown by metal organic chemical vapour deposition on n-type 6H-SiC substrates are reported. The diode structures consist of an n + -GaN layer grown on the substrate, followed by a 2.5 mum unintentionally doped i-GaN layer, and a p-type GaN layer capped with a p ++ -GaN contact layer. The mesa-structure pin diodes exhibited a blocking voltage as large as V r ~-500 V, at a reverse current density of I r ~1 A/cm 2 . The on-resistance is 2.3 mOmega middot cm 2 for an 80 mum mesa diameter circular device. This yields a power figure of merit value of 108.69 MW/cm 2 . The on-resistance and the figure of merit values are believed to be the best reported for vertical mesa-geometry GaN pin rectifiers grown on 6H-SiC substrates with comparable i-layer thickness
Physiological responses of lichens to factorial fumigations with nitric acid and ozone.

Abstract This paper addresses the effects of gaseous nitric acid (HNO 3 ) and ozone (O 3 ), two important air pollutants, on six lichen species with different morphological, ecological, and biological characteristics. The treatment chambers were set up in a factorial design consisting of control chambers, chambers fumigated with HNO 3 , with O 3 , and with HNO 3 and O 3 , together. Each species showed a different sensitivity to the fumigations, reflecting the physiological variation among species. Our results clearly indicate that HNO 3 is a strong phytotoxin to many lichens, and that O 3 alone has little effect on the measured parameters. The combined fumigation effects of HNO 3 and O 3 were not significantly different from HNO 3 alone.
Endobronchial Ultrasonography with Transbronchial Needle Aspiration to Sample a Solitary Substernal Thyroid Nodule: A New Approach

Sampling of solitary thyroid nodules (STNs) is a common procedure performed for cytological diagnosis. The easiest and safest method is ultrasound guided fine needle aspiration biopsy (US-FNAB). This technique is usually performed under local anaesthesia in an office setting. In contrast, sampling a substernal STN could prove to be more difficult and problematic, and sometimes requires more invasive procedures. We describe a case of substernal thyroid nodule, where malignancy was excluded using endobronchial ultrasonography with transbronchial fine needle aspiration (EBUS-TBNA). We emphasise the feasibility and safety of EBUS-TBNA in sampling retrosternal thyroid nodules. In appropriate settings, this procedure can help avoid more invasive testing, and subsequently decrease the cost and complications.
The 25th anniversary of catalytic chain transfer

The transfer of hydrogen from a free radical to an olefin is catalyzed by some cobalt chelates. This reaction, when used in free-radical polymerization, can be called catalytic chain transfer (CCT) to a monomer. It allows the manufacture of oligomers that have defined molecular weights and are useful for a variety of applications. Because all the oligomers are getting terminal double bonds, they can behave as macromers. These macromers give rise to the formation of diblock and graft copolymers, telechelic polymers that have the same or different functional groups depending on the conditions and origins of the comonomers. The catalyst structure–property relation is discussed. Redox properties affect the CCT and provide additional leverage in controlling polymerization processes. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1753–1766, 2000
The Burgeoning HIV/HCV Syndemic in the Urban Northeast: HCV, HIV, and HIV/HCV Coinfection in an Urban Setting

Introduction Despite recommendations for generation-based HCV and once lifetime HIV screening, thousands of individuals in the U.S. still remain untested and undiagnosed. This cross-sectional study examines the correlates of HCV and HIV monoinfection and HIV/HCV coinfection in an urban Northeast setting.
Computer simulation of high-speed spinning of PET

An interactive computer simulation of the steady-state melt spinning of poly(ethylene terephthalate) was developed based upon a combination of physical laws and empirical relationships. The simulation incorporates crystallization effects which makes it valid for a wide range of take-up speeds. Modifications to the conventional threadline that allow judicious control over the threadline dynamics were modeled and included in the simulation for exploration of the effects of these perturbations. The modifications include quenching and on-line zone heating. The simulation was verified using experimental measurements of threadline diameter, velocity, and temperature at 3000, 4000, 5000, and 6000 m/min take-up. Off-line measurements of crystallinity and birefringence were also compared with the values calculated by the simulation at these speeds. © 1995 John Wiley & Sons, Inc.
Antares Reference Telescopes System

Antares is a 24-beam, 40-TW carbon-dioxide laser fusion system currently nearing completion at the Los Alamos National Laboratory. The 24 beams will be focused onto a tiny target (typically 300-1000 pm in diameter) located approximately at the center of a 7.3-m diameter by 9.3-m long vacuum (10-6 torr) chamber. The design goal is to position the targets to within 10 μm of a selected nominal position, which may be anywhere within a fixed spherical region 1 cm in diameter. The Antares Reference Telescope System is intended to help achieve this goal for alignment and viewing of the various targets used in the laser system. The Antares Reference Telescope System consists of two similar electro-optical systems positioned in a near orthogonal manner in the target chamber area of the laser. Each of these consists of four subsystems: 1) a fixed 9X optical imaging subsystem which produces an image of the target at the vidicon; 2) a reticle projection subsystem which superimposes an image of the reticle pattern at the vidicon; 3) an adjustable front-lighting subsystem which illuminates tne target; and 4) an adjustable back-lighting subsystem which also can be used to illuminate the target. The various optical, mechanical, and vidicon design considerations and trade-offs are discussed. The final system chosen (which is being built) and its current status are described in detail.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Major histocompatibility complex class II gene frequencies by serologic and deoxyribonucleic acid genomic typing in idiopathic dilated cardiomyopathy

Certain immunologic features associated with idiopathic dilated cardiomyopathy (IDC) suggest an infectious and/or autoimmune etiology. In this regard, an association between the major histocompatibility complex class II allele, DR4, and increased risk for IDC was previously identified. In the present report, 43 additional patients with IDC and 236 control subjects were studied for major histocompatibility class II allele associations. DR alleles were identified by microcytotoxicity. No significant differences between control subjects and patients with IDC were seen, although the frequency of DR4 was increased among patients. DR4 subtyping (n = 9) was performed by “dot blot” hybridization of allele-specific oligonucleotide probes to PCR-amplified genomic deoxyribonucleic acid. The DRB1∗0401 and DRB1∗0404 alleles were each found in 44% (n = 4) of patients with IDC, and DRB1∗0407 was identified in 1 patient (11%). DQ and DP alleles were identified by restriction endonuclease codigestion of polymerase chain reaction-amplified deoxyribonucleic acid. The digested fragments were separated and identified by polyacrylamide gel electrophoresis. Differences between patients and control subjects were observed for DQA1∗0501 (11% of patients vs 28% of control subjects, p < 0.05) and DQB1∗0201 (13% patients vs 25% control subjects, p < 0.05). A modest difference was noted for DQA1∗0301 (35% patients vs 23% control subjects, p = 0.08). These findings suggest a complex immune-related etiology for IDC that cannot be explained solely by the presence or absence of a single class II allele. However, this and other studies continue to implicate genes within the class II region in determining the risk for IDC.
Separation of deuterium by IR multiphoton decomposition of chlorodifluoromethane. IR multiphoton absorption by and decomposition of a CF2DCl/CF2HCl mixture

Abstract IR multiphoton absorption by various pressures of CF 2 HCl or of 1??? CF 2 DCl in CF 2 HCl was studied at several 9P and 10R lines of the CO 2 laser using temporally unmodified pulses. Values of 〈 n 〉 for the individual molecules, and thus the optical selectivities, obtained from these data indicate that the molecule is not a promising candidate for deuterium separation in these frequency ranges. A measurement of D-isotope depletion during the multiphoton decomposition of the same mixture at 9P42 (1025.2 cm −1 ) gave a minimum estimate of the isotopic selectivity of the dissociation process of 35.
MAXIMUM LIKELIHOOD ESTIMATION OF GRAVITY MODEL PARAMETERS

. It is shown that, under some very mild conditions, maximum likelihood estimates of gravity model parameters exist and are unique (up to a scale transformation for some parameters). An algorithm for finding such estimates is also proposed.
Reducing the Rates of Indeterminate Results of the QuantiFERON‐TB Gold In‐Tube Test During Routine Preemployment Screening for Latent Tuberculosis Infection Among Healthcare Personnel

We implemented the QuantiFERON-TB Gold (QFT-G) In-Tube test to identify latent tuberculosis infection among potential employees prior to employment. The rates of indeterminate QFT-G In-Tube test results were higher than expected and prompted an investigation that led to successful interventions (eg, manual vortexing before incubation and the use of a modified in-tube method). The tracking of indeterminate results is suggested as an important quality control measure.
The needle knife: a valuable tool in diagnostic and therapeutic ERCP

Using monopolar electrocautery technique, we have used both an electrified guide wire and a needle-tipped sphincterotome to successfully enter the common bile duct, subsequently image it, and perform therapeutic procedures when by virtue of the patient's anatomy, or because of tumor, this had not been possible using conventional ERCP catheters. In an initial group of 45 patients using the needle-tipped sphincterotome, clinically significant complications occurred in 3 patients but were not of a serious nature. The technique was an effective method for achieving both diagnostic ERCP and therapeutic maneuvers in 43 of 45 patients. We stress that this technique should only be attempted by those with long experience in ERCP and related procedures.
Adsorption of RDX and TATP on IRMOF-1: an ab initio study

The adsorption of 1,3,5-trinitro-s-triazine (RDX) and triacetone triperoxide (TATP) on representative fragments of metal organic framework (IRMOF-1) was studied at the B3LYP/6-31G(d) level of theory. For examined adsorbates several possible adsorption positions toward the IRMOF-1 fragments were found. The adsorption strength of the adsorbate on IRMOF-1 is largely affected by the geometry of the active site of IRMOF-1 which controls the orientation of the target molecule with respect to the IRMOF-1 fragment. The calculations show that the adsorption on these fragments occurs due to the formation of hydrogen bonds between the molecular C–H groups and the oxygen atoms of IRMOF-1. The RDX and TATP molecules are the most strongly adsorbed on the linker fragment of IRMOF-1. This type of adsorption results in the polarization of RDX and TATP on the IRMOF-1 fragments. The interaction energy of two most stable RDX-, and TATP-IRMOF-1 adsorption systems are −9.8 and −12.8 kcal/mol, respectively. It can be concluded that the 1,4-benzenedicarboxylate site of IRMOF-1 shows the stronger molecular adsorption of RDX and TATP than the site containing [Zn4O(CO2)6] and also it is characterized by higher reactivity than the other considered sites. The binding of studied explosive molecules to IRMOF-1 consists of interplay between attractive interactions between the target molecule and MOF as well as the shielding by the IRMOF-1 fragment induced by the molecular adsorption. The relative importance of these effects depends on the chemical nature, the size, and the shape of the molecule and MOF. Small-size molecules require smaller space for the adsorption and also they are less shielded by the sizeable adsorbent. So they interact better when adsorbed on larger IRMOF-1 fragment. On the other side, larger molecules show higher adsorption strength with small fragments of IRMOF-1.
Seeding prosperity and revitalizing corridors decision tools for community engagement and urban vacant land remediation

The SPARC Systems Synthesis Project (SSSP) assists in the development of an efficient and innovative approach to vacant lot revitalization by devising a toolkit to support decisions about the green redevelopment of abandoned and vacant land. Utilization of this analysis will serve to demonstrate where and how designated vacant lots will benefit from the process of green intervention strategies.
MICROWAVE MEASUREMENT-PARAMETER OPTIMIZATION FOR DETECTION OF SURFACE BREAKING HAIRLINE CRACKS IN METALS

Abstract Fatigue and stress induced hairline surface crack detection in metals is an important practical issue. A newly developed microwave inspection approach, using an open-ended rectangular waveguide, has proved to be an effective tool for detecting such cracks. This novel microwave approach overcomes some of the limitations associated with the standard detection methods for surface crack detection. In addition, this approach is applicable to exposed and filled cracks (with a dielectric such as dirt, rust, etc.), and cracks under dielectric coatings such as paint and composite dielectric laminates. This paper briefly presents the basic foundation of this surface crack detection methodology. More importantly, this paper focuses on the ways by which measurement parameters may be optimized for increased crack detection sensitivity. Theoretical as well as experimental results are provided.
Identification and Localization of Plasminogen Activator Inhibitor-1 Within the Porcine Oviduct

Abstract The porcine oviduct synthesizes de novo and secretes a number of proteins into culture medium, many of which are unidentified. The objectives of the present study were to 1) semipurify and identify a Mr 45 000 secreted protein of the oviduct, 2) examine its synthesis within the three functional segments (infundibulum, ampulla, and isthmus), and 3) evaluate its distribution throughout the oviduct. Oviductal tissue was collected during early pregnancy, divided into functional segments, and subsequently cultured. Medium was collected, and the Mr 45 000 protein was concentrated by gel-filtration chromatography. The semipurified protein was transferred onto a polyvinylidene fluoride membrane and subjected to N-terminal amino acid analysis. The 26-amino acid sequence was 96% identical to that of pig plasminogen activator inhibitor (PAI)-1. Analysis by 1-dimensional SDS-PAGE and fluorography of rabbit anti-human PAI-1-immunoprecipitated product confirmed PAI-1. Subsequent 2-dimensional SDS-PAGE and fluo...
Zinc: A possible role in the reversal of uremic impotence

Eight males on hemodialysis with (1) sexual desire, (2) an organic etiology of their impotence, and (3) an available and willing sexual partner were randomly divided into two equal groups. One group received dialytic administration of zinc and the other received a placebo. Sexual functioning improved in only 25% of the zinc treated group and in none of the control group. Free or serum testosterone levels decreased in all four of the zinc treated subjects. The lack of sexual improvement in the zinc treated group either reflects (1) zinc's lack of therapeutic efficacy, (2) irreversible Leydig cell damage or (3) a nonendocrine organic etiology of the impotence.
Reduced Anterior Corpus Callosum White Matter Integrity is Related to Increased Impulsivity and Reduced Discriminability in Cocaine-Dependent Subjects: Diffusion Tensor Imaging

Brain imaging studies find evidence of prefrontal cortical dysfunction in cocaine-dependent subjects. Similarly, cocaine-dependent subjects have problems with behaviors related to executive function and impulsivity. Since prefrontal cortical axonal tracts cross between hemispheres in the corpus callosum, it is possible that white matter integrity in the corpus callosum could also be diminished in cocaine-dependent subjects. The purpose of this study was to compare corpus callosum white matter integrity as measured by the fractional anisotropy (FA) on diffusion tensor imaging (DTI) between 18 cocaine-dependent subjects and 18 healthy controls. The Barratt Impulsiveness Scale (BIS-11) and a continuous performance test: the Immediate and Delayed Memory Task (IMT/DMT) were also collected. Results of the DTI showed significantly reduced FA in the genu and rostral body of the anterior corpus callosum in cocaine-dependent subjects compared to controls. Cocaine-dependent subjects also had significantly higher BIS-11 scores, greater impulsive (commission) errors, and reduced ability to discriminate target from catch stimuli (discriminability) on the IMT/DMT. Within cocaine dependent subjects there was a significant negative correlation between FA in the anterior corpus callosum and behavioral laboratory measured impulsivity, and there was a positive correlation between FA and discriminability. The finding that reduced integrity of anterior corpus callosum white matter in cocaine users is related to impaired impulse control and reduced ability to discriminate between target and catch stimuli is consistent with prior theories regarding frontal cortical involvement in impaired inhibitory control in cocaine-dependent subjects.