cssi/SciSciGPT-SciSciNet huggingface dataset:
Enhanced vulnerability to tobacco use in persons with diabetes: A behavioral and neurobiological framework

Tobacco use significantly magnifies the negative health complications associated with diabetes. Although tobacco use is strongly discouraged in persons with diabetes, clinical evidence suggests that they often continue to smoke and have more difficulty quitting despite serious contraindications. Here, we suggest that a potential reason for enhanced vulnerability to tobacco use in persons with diabetes is greater rewarding effects of nicotine. This review summarizes pre-clinical evidence indicating that the rewarding effects of nicotine are enhanced in rodent models of type 1 and type 2 diabetes. We also provide a framework of neurobiological mechanisms that are posited to promote tobacco use in persons with diabetes. This framework suggests that diabetes induces a disruption in insulin signaling that leads to a suppression of dopamine systems in the mesolimbic reward pathway. Lastly, we consider the clinical implications of enhanced rewarding effects of nicotine that may promote tobacco use in persons with diabetes. The clinical efficacy of smoking cessation medications that enhance dopamine are important to consider, given that persons with diabetes may display disrupted dopaminergic mechanisms. Future work is needed to better understand the complex interaction of dopamine and insulin in order to develop better smoking cessation medications for persons with diabetes.
High Temperature Performance of High-efficiency, Multi-layer Solar Selective Coatings for Tower Applications☆

Abstract The roadmap to next-generation concentrating solar power plants anticipates a progression to central towers with operating temperatures in excess of 650 °C. These higher temperatures are required to drive higher power-cycle efficiencies, resulting in lower cost energy. However, these conditions also place a greater burden on the materials making up the receiver. Any novel absorber material developed for next-generation receivers must be stable in air, cost effective, and survive thousands of heating and cooling cycles. The collection efficiency of a power tower plant can be increased if the energy absorbed by the receiver is maximized while the heat loss from the receiver to the environment is minimized. Thermal radiation losses can be significant (>7% annual energy loss) with receivers at temperatures above 650 °C. We present progress toward highly efficient and durable solar selective absorbers (SSAs) intended for operating temperatures from 650 °C to 1000 °C. Selective efficiency (ηsel) is defined as the energy retained by the absorber, accounting for both absorptance and emittance, relative to the energy incident on the surface. The low emittance layers of multilayer SSAs are binary compounds of refractory metals whose material properties indicate that coatings formed of these materials should be oxidation resistant in air to 800-1200 °C. On this basis, we initially developed a solar selective coating for parabolic troughs. This development has been successfully extended to meet the absorptance and emittance objectives for the more demanding, high temperature regime. We show advancement in coating materials, processing and designs resulting in the initial attainment of target efficiencies ηsel> 0.91 for proposed tower conditions. Additionally, spectral measurements show that these coatings continue to perform at targeted levels after cycling to temperatures of 1000 °Cin environments of nitrogen and forming gas.
Insights from mosquito evolution: Patterns, tempo and speciation

A great deal of information has accumulated on chromosome morphology and evolution, heterochromatin distribution and differentiation, and molecular structure, organization and evolution of genomes in the mosquito family Culicidae. Whereas numerically the haploid chromosome number (n = 3) has remained virtually unchanged, extensive variation exists at different levels of genomic structure and organization. A number of trends in genome evolution emerge when these data are considered in light of cladistic phylogenies of Culicidae and its sister families. Anophelinae have heteromorphic sex chromosomes, a small genome size and repetitive elements are distributed in a long-period interspersion pattern. In contrast, Culicinae have homomorphic sex chromosomes and repetitive DNA is organized in a short-period interspersion pattern. There has been a general increase in genome size during the evolution of culicine taxa. The most likely hypothesis for the evolution of sex chromosomes and genome organization in Culicidae would be that homomorphic sex chromosomes and a long-period interspersion pattern are ancestral in lineages leading to Toxorhynchitinae and Culicinae. Larger genomes developed in subsequent culicine lineages through accumulation of short-period interspersed repetitive elements. Heteromorphic sex chromosomes evolved early in the evolution of Anophelinae and a long-period interspersion pattern was retained. An alternative route may be that Culicidae arose from a Chaoborid Mochlonyx-like ancestor with heteromorphic sex chromosomes and possibly short-period interspersion. This would require the loss of heteromorphic sex chromosomes in the lineage leading to Toxorhynchitinae and Culicinae and ‘shedding’ of repetitive elements in the lineage leading to Anophelinae. Several interesting patterns have emerged from studies of C-banding and the distribution of heterochromatin in Culicidae and phylogenies derived from these studies are supported by the modern cladistic analyses.
Flow Instabilities in Non-Uniformly Heated Helium Jet Arrays Used for Divertor PFCs

In this study, due to a lack of prototypical experimental data, little is known about the off-normal behavior of recently proposed divertor jet cooling concepts. This article describes a computational fluid dynamics (CFD) study on two jet array designs to investigate their susceptibility to parallel flow instabilities induced by non-uniform heating and large increases in the helium outlet temperature. The study compared a single 25-jet helium-cooled modular divertor (HEMJ) thimble and a micro-jet array with 116 jets. Both have pure tungsten armor and a total mass flow rate of 10 g/s at a 600 °C inlet temperature. We investigated flow perturbations caused by a 30 MW/m2 off-normal heat flux applied over a 25 mm2 area in addition to the nominal 5 MW/m2 applied over a 75 mm2 portion of the face. The micro-jet array exhibited lower temperatures and a more uniform surface temperature distribution than the HEMJ thimble. We also investigated the response of a manifolded nine-finger HEMJ assembly using the nominal heat flux and a 274 mm2 heated area. For the 30 MW/m2 case, the micro-jet array absorbed 750 W in the helium with a maximum armor surface temperature of 1280 °C and a fluid/solid interface temperature of 801more » °C. The HEMJ absorbed 750 W with a maximum armor surface temperature of 1411 °C and a fluid/solid interface temperature of 844 °C. For comparison, both the single HEMJ finger and the micro-jet array used 5-mm-thick tungsten armor. The ratio of maximum to average temperature and variations in the local heat transfer coefficient were lower for the micro-jet array compared to the HEMJ device. Although high heat flux testing is required to validate the results obtained in these simulations, the results provide important guidance in jet design and manifolding to increase heat removal while providing more even temperature distribution and minimizing non-uniformity in the gas flow and thermal stresses at the armor joint.« less
Growth in children after bone marrow transplantation: busulfan plus cyclophosphamide versus cyclophosphamide plus total body irradiation.

Growth was assessed during the first and second years following bone marrow transplantation (BMT) in 47 children treated by either busulfan plus cyclophosphamide (BU/CY) (n = 24) or cyclophosphamide plus fractionated total body irradiation (CY/TBI) (n = 23). Before transplant, the median height was only 0.2 SD below age- and sex- adjusted means (range, -2.5 to +3.0). Height was greater than 2.0 SD below normal in only three patients (6%). The pretransplant heights were comparable in the BU/CY and CY/TBI groups (-0.1 v -0.6 SD, P = .35). Following transplant, median 1- and 2-year heights were 0.7 and 0.9 SD below normal, respectively. Growth rates were 2.2 SD and 1.4 SD below normal during the first and second years, respectively. Growth rates were greater than 2.0 SD below normal in 24 of 47 (51%) at 1 year and in 12 of 31 (39%) at 2 years after transplant. Growth rates in patients treated with BU/CY were comparable to those treated with CY/TBI during both years: -2.5 versus -1.7 SD during the first year (P = .19, Wilcoxon), and -1.5 versus -1.1 SD during the second year (P = .61). Growth rates during the second year correlated with growth rates during the first year (r = .36, P = .046). Growth rates during the first year were lower in patients who had been given prior cranial irradiation, those who were near pubertal age at the time of transplant, and those who were transplanted for a disease other than acute lymphoblastic leukemia (ALL). During the second year, poor rates of growth were associated only with the use of corticosteroids after transplant.
From fuzzification and intervalization to anglification: a new 5D geometric formalism for physics and data processing

We show that in understanding foundations of modern physics, with its 10-dimensional (and higher-dimensional) space-time models, it is very helpful to use the main ideas behind fuzzification - extension of arithmetic operations and elementary functions from exact numbers to fuzzy numbers. The resulting formalism is, from the mathematical viewpoint, somewhat more complex than the traditional fuzzy arithmetic, but it is still much simpler than the quantum field theory - and thus, it helps to make several important ideas from foundations of modern physics much more intuitively clear.
Chemokines and viral diseases of the central nervous system

Publisher Summary This chapter discusses chemokines and their receptors in the evolution of viral infectious diseases of the central nervous system (CNS). Infection of the human CNS with many different viruses or infection of the rodent CNS induces vigorous host-inflammatory responses with recruitment of large numbers of leukocytes, particularly T lymphocytes and macrophages. Chemokines coordinate trafficking of peripheral blood leukocytes by stimulating their chemotaxis, adhesion, extravasation, and other effector functions. In view of these properties, research efforts have turned increasingly to the possible involvement of chemokines in regulating both peripheral tissue and CNS leukocyte migration during viral infection. The biological effects of chemokines are mediated via their interaction with receptors belonging to the family of seven transmembrane (7TM)-spanning, G-protein coupled receptors (GPCRs). In the normal mammalian CNS, the number of leukocytes present in the brain is scant. However, these cells are attracted to, and accumulate in, a variety of pathologic states, many involving viral infection. Although leukocyte migration into local tissue compartments, such as the CNS, is a multifactorial process, it has become clear that chemokines are pivotal components of this process, providing a necessary chemotactic signal for leukocyte recruitment.
Simulating plasma production from hypervelocity impacts

Hypervelocity particles, such as meteoroids and space debris, routinely impact spacecraft and are energetic enough to vaporize and ionize themselves and as well as a portion of the target material. The resulting plasma rapidly expands into the surrounding vacuum. While plasma measurements from hypervelocity impacts have been made using ground-based technologies such as light gas guns and Van de Graaff dust accelerators, some of the basic plasma properties vary significantly between experiments. There have been both ground-based and in-situ measurements of radio frequency (RF) emission from hypervelocity impacts, but the physical mechanism responsible and the possible connection to the impact-produced plasma are not well understood. Under certain conditions, the impact-produced plasma can have deleterious effects on spacecraft electronics by providing a new current path, triggering an electrostatic discharge, causing electromagnetic interference, or generating an electromagnetic pulse. Multi-physics simula...
Limited T-cell receptor beta-chain diversity of a T-helper cell type 1-like response to Mycobacterium leprae.

Abstract Delayed-type hypersensitivity (DTH) is the standard measure of T-cell responsiveness to infectious organisms. For leprosy, the Mitsuda reaction, a local immune response to cutaneous challenge with Mycobacterium leprae, is considered to represent a measure of DTH against the pathogen. We analyzed the diversity of the T-cell receptor beta-chain repertoire in Mitsuda reactions to determine the breadth of the mycobacterial antigens involved. The polymerase chain reaction was used to compare V beta usage in the Mitsuda reaction T-cell lines established and unstimulated peripheral blood. These molecular analyses revealed a skewed T-cell receptor V beta gene usage in the Mitsuda reaction and in T-cell lines from lesions. To examine the reactivity of T cells from these lesions, T-cell lines were tested against the available native and recombinant antigens of M. leprae. T-cell lines derived from Mitsuda reactions responded more strongly to the 10-kDa M. leprae antigen, a homolog of GroES in Escherichia coli, than to other M. leprae proteins. T-cell lines were also shown to proliferate strongly in response to the 17- and 3-kDa proteins. The pattern of the lymphokine mRNA of these cells was reminiscent of the pattern of murine TH1 cells, positive for interleukin-2 and gamma interferon and weakly positive for interleukin-4. These data indicate that a limited array of T cells, perhaps recognizing stress proteins, secrete a type 1 lymphokine profile in the DTH response to mycobacteria.
Storage of digital camera images

We describe a simple technique to improve the quality of images that are compressed for storage on a digital camera. We assume that the camera is designed to store a fixed number of images, and that lossy rate controlled compression is used to ensure that each image fits in the space allocated to it. Whenever the user takes fewer than the maximum allowed number of images a portion of the disk is empty, which is wasteful. Ideally we would like to make full use of the storage space, and not leave any empty. We show that when an image is JPEG compressed it is possible to produce a secondary compressed version for marginal additional computation. At the decoder the secondary version allows decoding of the image with much greater fidelity than is possible using the primary alone. Thus if the user takes half or fewer of the maximum allowed number of images, each will be reconstructed with far greater fidelity, and some images will always have enhanced quality provided that the disk does not fill.
Olmsted's Police

The urbanization of nineteenth century America led to enormous changes in American criminal justice, as the rise of this dramatically more complex kind of human settlement posed new problems for legal regulation. Some of those problems are familiar. Many reformers emphasized the way cities eroded traditional controls on predatory crime, and they viewed modern police forces, public prosecution, and the modern penitentiary as a means of substituting formal social control for the informal controls of the past. But cities posed a different problem as well. In the city people made their homes in dense mixed-use environments that had not yet been sorted out and segregated along the lines of the modern metropolis, and when they ventured out of them they came together in the crowded streets, squares, and parks that proliferated in the nineteenth century. This complex environment made new demands on their behavior, as conduct that would have bothered no one in sparsely occupied rural spaces became problematic in the densely shared environments of the city. This change did not involve the collapse of old strategies for controlling familiar forms of bad behavior; it involved a shift in what sort of behavior counted as “bad” in the first place. The continued evolution of the urban environment, in turn, depended upon the ability of criminal justice institutions to grapple with these challenges. Shared environments require those who use them to develop and enforce rules to regulate the sharing.
A cyclical view of the relationship between corporate governance and strategic management

The vast majority of research on the relationship between corporate governance and strategic management focuses on the impact of corporate governance on strategic management. In this article we propose a cyclical model, highlighting that strategic decisions can also affect corporate governance through shaping firm ownership structure. We discuss the impacts of strategic decisions on firm ownership structure and corporate governance in the contexts of publicly traded firms, private firms, and the privatization of state-owned enterprises. We hope that our cyclical model can promote researchers to develop a more complete view about the relationships between strategic management, ownership structure, and corporate governance.
Microstructural Development and Catalytic Performance of Au−Pd Nanoparticles on Al2O3 Supports: The Effect of Heat Treatment Temperature and Atmosphere

Au−Pd nanoparticles supported on a variety of oxides are known to be highly active catalysts for a number of interesting reactions, including the direct synthesis of H2O2 from H2 and O2. A systematic series of Au−Pd/Al2O3 catalysts, subjected to a variety of heat treatments, have been examined by STEM-XEDS and XPS in an effort to track the microstructural development of the bimetallic particles. It was observed that the nature and size distribution of the AuPd particles was highly dependent upon both the heat treatment temperature and the atmosphere. As synthesized particles were homogeneous alloys, but subsequent calcination in air produced metal particles which showed a progressive enrichment of Pd at their surface. The change from homogeneous alloy to Pd-rich shell/Au-rich core morphology and increase in average particle size induced by the calcination treatment was accompanied by a significant decrease in the activity of the catalyst. However, the calcination step is deemed to be necessary to produce ...
State of heme in heme c systems: Cytochrome c and heme c models

Polarized resonance Raman spectra of horse heart ferricytochrome c as a function of pH in the range 1.0–12, in the presence of the extrinsic ligands imidazole, cyanide, and azide, and in 4 M urea, are reported, as are resonance Raman spectra of heme undecapeptide in the presence of imidazole, pH 6.8 and pH 2.0, and with cyanide at pH 6.8. The range of investigation is 140–1700 cm−1, using the 5145-, 4880-, and 4579-A excitations. The spectra have been analyzed in terms of complexity, sensitivity, and the conformation-heme energetics of the systems. The state of heme in various forms is analyzed with regard to heme energetics, core size, nature of planarity, and coordination configuration. All low-spin forms of heme c systems, cytochrome c, and heme models are concluded to be hexacoordinated, in-plane heme iron systems. The effect of the location of the heme in the protein environment is found to be a slight expansion of the porphyrin core, ∼0.01 A, while the covalent linkage of heme to protein and a mixed nature of axial coordination configuration seem to have little effect on the energetics of the heme group. Complex formation with extrinsic ligand, imidazole, cyanide, or azide, results in a slight contraction of the heme core. The formation of cytochrome c form IV, the alkaline form, is shown to follow a process with apK a of about 8.4, and similarly, acidic form II is created following the prior formation of an intermediate form with apK a of about 3.6. The precursor to form IV is interpreted as containing perturbation of the pyrrol rings, whereas the precursor to the acidic form seems to reflect alteration of the energetics of the CαCmα structures of the heme group. The acidic form of heme undecapeptide is a hexacoordinated high-spin heme with an estimated displacement of 0.25 A from the heme plane. The pH 2 form of cytochrome c is also a hexacoordinated high-spin form with two weak axial ligands, but iron is in the plane of the porphyrin ring.
1091 AGE RELATED RESPONSE TO HEMOPHILUS INFLUENZAE TYPE B VACCINES

Safety and age related immunogenicity of 2 HIB vaccines, prepared by Lederle Laboratories, polyribosylribitol phosphate (PRP) and PRP-pertussis (PRP-p) were compared in 3 groups of normal children aged 6-7 months,15-18 months and 3-6 years. Children in the older age groups received a single dose of 1 of the HIB vaccines or DPT. Children aged 6-7 months received either: 1) 2 monthly doses of an HIB vaccine, 2) DPT followed 1 month later by PRP or 3) PRP-p followed by DPT. Reactions were evaluated at 24 hours and RIA antibody (method of Anderson) determined at 1 month after injections. In the 2 older age groups,mild-moderate local and/or systemic reactions were similar for PRP-p (4/10 injections) and DPT (5/10 injections). PRP was without reactions. 6-7 month old children tolerated PRP-p and PRP equally well with 3/31 and 4/31 injections causing reactions. In contrast, 12/22 DPT injections caused reactions. Serologic responses to both HIB vaccines were age dependent. The ratio of post-pre geometric mean titers: The addition of pertussis to PRP enhanced antibody response to the HIB polysaccharide antigen and holds promise as an approach to immunization.
Picosecond recombination of photo-excited carriers in sputtered a-Si:H

Abstract The decay kinetics of photo-excited carriers in r.f. sputtered a-Si:H have been investigated on a picosecond time scale. Decay curves were in agreement with a two-step recombination process for a-Si:H. Results are compared to previous measurements on glow-discharge a-Si:H.
Reply regarding pediatric salivary gland imaging

Sir, We thank Gadodia et al. [1] for their interest in our pictorial essay [2] and for clarifying the definition of accessory parotid gland tissue. We agree with their comment and would also like to reiterate the take-home point regarding accessory parotid tissue, which, given its high predominance, should not be mistaken for a mass. Regarding the comment on our omission of chronic recurrent parotitis, we did so because it is not typically imaged and often managed on a clinical basis. However, the interesting points made by Gadodia et al. [1] regarding chronic recurrent parotitis are notable, and it is certainly a diagnosis with which one should be familiar.
A Summer Blender Camp: Modeling, Rendering, and Animation for High School Students

At Camp Blender, high-school students of varying backgrounds learned how to use the Blender software package to create computer graphics content. In a postclass survey, most of them indicated that the camp affected how they thought about their career path.
The International Food Policy Research Institute (IFPRI) and the Mexican PROGRESA anti-poverty and human resource investment conditional cash.

Summary The Mexican PROGRESA/Oportunidades anti-poverty and human resource conditional cash transfer (CCT) program has influenced considerably policies in many countries. The Mexican government engaged the International Food Policy Research Institute (IFPRI) to undertake the initial evaluation of PROGRESA/Oportunidades. This paper considers: (1) Was the PROGRESA program design influenced by prior IFPRI research? (2) Why was IFPRI chosen to undertake the initial impact evaluation of PROGRESA ? (3) How did the IFPRI evaluation of PROGRESA contribute to the program? (4) Were there spillovers of the IFPRI evaluation of PROGRESA ? It concludes that estimated benefit–cost ratios of IFPRI’s evaluation of PROGESA considerably exceed one.
Regulation in molluscan muscles

In molluscan muscles the factors which regulate contraction by interacting with calcium are associated with myosin. Purified myosin preparations from the striated and smooth muscles of Aequipecten and from the smooth red adductor muscle of Mercenaria bind calcium with a great affinity and the ATPase activity of this myosin combined with purified actin requires calcium. The actin-containing thin filaments of these muscles do not bind calcium and although they activate the ATPase of rabbit myosin this activity is not calcium dependent. The thin filaments of molluscs, however, combine readily in vitro with the relaxing proteins of rabbit and behave, then, like rabbit preparations. The components responsible for calcium binding and for the calcium dependence of ATPase cannot readily be removed from molluscan myosin and are not obtained from molluscan muscles or actomyosins by procedures successfully applied to rabbit preparations. Tropomyosin does not appear to be necessary for the regulation of molluscan actomyosin by calcium. It is likely that in molluscs the calcium-binding component interacts directly with myosin to prevent cross-bridge formation. The possibility that in vertebrate muscles cross-bridge formation may also be controlled by a direct interaction of some of the regulatory proteins with-myosin is discussed.
Parameter Sensitivity In Vector Controlled Ac Motor Drives

The relatively recent development of the theory of vector control has enabled ac machines to be transformed, performance wise, into equivalent separately excited dc machines while retaining the many advantages that ac machines have over dc. The ac machines used include the induction and permanent magnet synchronous motors. A precise knowledge of the machine parameters is needed in order to implement indirect vector control on induction motor drive systems where the position of the rotor flux is not measured. If the machine parameters change relative to the preset values in the vector controller, then the decoupling of the torque and flux channels, which is the object of vector control, is lost. Low frequency torque and speed oscillations can result with a consequent degradation in the drive performance. The PMSM drive system is also parameter sensitive although not depending on the same parameters as the induction motor drive. It is well known that machine parameters change with temperature, saturation and on the frequency of operation. An assessment of the overall performance of an ac motor drive must therefore include a study of its parameter sensitivity. In this paper, a detailed steady state study of parameter sensitivity for both the induction and permanent magnet machines is done. Comparisons are also made based on the results of this investigation.
Influence of non-classical elastic-plastic constitutive features on shock wave existence and spectral solutions

Theinfluence of non-classical elastic-plastic constitutive features on dynamically moving discontinuities in stress, strain and material velocity is investigated. Non-classical behavior here includes non-normality of the plastic strain increment to the yield surface, plastic compressibility, pressure sensitivity of yield and dependence of the elastic moduli on plastic strain. Drugan and Shen's (1987) analysis of dynamically moving discontinuities with strain as well as stress jumps in classical materials is shown to be valid for a broad class of non-associative material models until deviation from normality exceeds a critical (non-infinitesimal) level. For these non-classical materials, an inequality that bounds the magnitude of the stress jump is derived, which is information not obtainable from a standard spectral analysis of a shock. For the special case of stress discontinuities with continuous strain or for quasi-static deformations, this inequality is shown to rule out jumps in specific projections of the stress tensor unless the non-normality is sufficiently large. These results invalidate a recent claim in the literature that an infinitesimal amount of non-normality permits moving surfaces of discontinuity in stress (with no strain jump) near the tip of a dynamically advancing crack tip. Using a very general plastic constitutive law that subsumes most non-classical (and classical) descriptions currently in use, a complete closed form solution is obtained for the plastic wave speeds and eigenvectors. A novel feature of the analysis is the clarity and completeness of the solutions. If the elastic part of the response is isotropic, one plastic wave speed equals the elastic shear wave speed, while the other two possible wave speeds depend in general on the stress and plastic strain within the shock transition layer. Concise necessary and sufficient conditions for real eigenvalues and for vanishing eigenvalues are derived. The real eigenvalues are classified by numerical sign and ordering relative to the elastic eigenvalues. The geometric multiplicity of plastic eigenvectors associated with elastic eigenvalues is shown to depend on the stress state within the shock transition layer. These solutions, several of which hold for arbitrary elastic anisotropy, are also applicable to acceleration waves and localization problems and to materials with dependence of the elastic moduli on plastic strain. Such elastic-plastic coupling is shown to imply a non-self-adjoint fourth order tangent stiffness tensor even if the plastic constitutive law is associative.
SU-E-J-174: Adaptive PET-Based Dose Painting with Tomotherapy

Purpose: PET imaging can be converted into dose prescription directly. Due to the variability of the intensity of PET the image, PET prescription maybe superior over uniform dose prescription. Furthermore, unlike the case in image reconstruction of not knowing the image solution in advance, the prescribed dose is known from a PET image a priori. Therefore, optimum beam orientations are derivable. Methods: We can assume the PET image to be the prescribed dose and invert it to determine the energy fluence. The same method used to reconstruct tissue images from projections could be used to solve the inverse problem of determining beam orientations and modulation patterns from a dose prescription [10]. Unlike standard tomographic reconstruction of images from measured projection profiles, the inversion of the prescribed dose results in photon fluence which may be negative and therefore unphysical. Two-dimensional modulated beams can be modelled in terms of the attenuated or exponential radon transform of the prescribed dose function (assumed to be the PET image in this case), an application of a Ram-Lak filter, and inversion by backprojection. Unlike the case in PET processing, however, the filtered beam obtained from the inversion represents a physical photon fluence. Therefore, a positivity constraintmore » for the fluence (setting negative fluence to zero) must be applied (Brahme et al 1982, Bortfeld et al 1990) Results: Truncating the negative profiles from the PET data results in an approximation of the derivable energy fluence. Backprojection of the deliverable fluence is an approximation of the dose delivered. The deliverable dose is comparable to the original PET image and is similar to the PET image. Conclusion: It is possible to use the PET data or image as a direct indicator of deliverable fluence for cylindrical radiotherapy systems such as TomoTherapy.« less
Metastable phase formation in rapidly solidified submicron powders of Al-30.3at.%Ge eutectic alloy

Abstract Submicron powders of an Al-30.3at.%Ge (eutectic) alloy produced by electrohydrodynamic atomization have been melted and rapidly solidified in a transmission electron microscope. A metastable phase, previously unreported in the literature, has been identified. Selected area diffraction analysis was used to determine the structure of this phase, which was found to be hexagonal (space group, P6/mmm) with a ≈ 1.42 nm and c ≈ 0.74 nm.
Surface photochemistry: 7. Synthesis on Pt(111) of surface ethyl groups and their rearrangement to ethylidyne

The vibrational spectra of photochemically produced adsorbed ethyl fragments and their thermal rearrangement products have been measured on Pt(111). Heating ethyl fragments, in the presence of adsorbed chlorine, leads to ethylidyne, but not directly; di-σ-bonded ethylene is formed as a relatively stable intermediate.
Military unit support, postdeployment social support, and PTSD symptoms among active duty and National Guard soldiers deployed to Iraq

Research suggests that military unit support and community postdeployment social support are associated with fewer PTSD symptoms following military deployment. This study extended prior research by examining the associations among predeployment unit support and PTSD symptoms before Iraq deployment as well as unit support, PTSD symptoms, and postdeployment social support after deployment among 835 U.S. Army and 173 National Guard soldiers. Multiple regression analyses indicated that predeployment unit support was not significantly associated with postdeployment PTSD severity in either group of soldiers, whereas higher unit support during deployment was significantly associated with lower postdeployment PTSD severity among active duty soldiers only. Among both groups, higher levels of postdeployment social support were associated with lower levels of postdeployment PTSD symptom severity. These findings suggest that postdeployment social support is a particularly strong buffer against postdeployment PTSD symptoms among both groups of soldiers whereas the effects of unit support may be limited.
Electron–proton and electron–methyl exchanges in pyrolysis of polyacetylene and polymethylacetylene

Pyrolysis of polyacetylene is marked by high yields of proton-enriched products methane, ethane, ethylene, propane, polypylene, butadiene, cyclopentadiene, 1,3-pentadiene, and toluene in total amounts exceeding benzene. The activation energies for their formation are low. Polyacetylene doped with AsF5 and iodine produced these products in even higher yields of two to 17 times of undoped polymers. The dominant mechanism is thought to be random-chain scission followed by electron–proton exchange reactions. Polymethylacetylene is thermally less stable than polyacetylene. Pyrolysis gave mesitylene as the expected main product. However, as in the case of polyacetylene, large amounts of proton-enriched products were formed with moderate activation energies. (The yields of methane, propylene, and propane are nearly the same in the pyrolysis of polymethylacetylene as compared to that of polyacetylene at 923°K referenced to mesitylene and benzene, respectively.) By analogy, mechanisms involving both electron-proton and electron–methyl exchange reactions were proposed to account for the formation of all the pyrolyzates of polymethylacetylene. These reactions, not observed in the pyrolysis of polypropylene and polyisoprene, are attributable to the conjugated backbone permitting facile migrations of electrons, protons, and methyl groups.
The relation between item identification difficulty and elaborative conceptual processing for children and adults

Abstract The four experiments concerned the relation between the difficulty of item identification processes, elaborative conceptual processing, and developmental differences in cued recall. Elaborative conceptual processing was manipulated by asking related (“How many are related?”), category (“How many are vehicles?”), and analytic (“How many usually carry freight?”) orienting questions about four-word stimuli in which the words were categorically related (Bus-Airplane-Car-Train). The measures of elaborative processing were the speed and accuracy of question answers. Cued recall for the targets (Train) was assessed for one-word (Bus) or two-word (Bus-Airplane) cues, which were varied to determine if elaborative processing affected cue discriminability or constructability, or both. The difficulty of item identification was varied in several ways. In Experiment 1, the graphemic information was degraded in the acquisition stimuli, or the retrieval cues, or the stimulus words were intact. In Experiments 2 and 3, acquisition presentation time was varied and the stimuli were readby the experimenter or the subject. Experiment 4 featured pictures to determine generalizability. The results showed that elaborative conceptual processing facilitates recall. Most important, item identification processes limit elaborative conceptual processing for both words and pictures, and more for children than for college students.
Detailed analyses of individual neutral lipid classes of Pneumocystis.

SUMMARY Individual neutral lipid classes of Pneumocystis carinii carinii were isolated and purifed by thin-layer chromatography. The fatty acids in steryl esters, triglycerides, free fatty acids, diglycerides, and monoglycerides were quantified by gas-liquid chromatography. The fatty acid compositions of these lipids were similar to those of the neutral lipid classes in whole rat lung controls, unlike comparable studies of phospholipid classes. The free fatty alcohols of rat lung controls and P. carinii were also identified and quantified; only saturated fatty alcohols were detected.
DEEP FAT FRYING CHARACTERISTICS OF BUTTEROIL

A study was undertaken to determine whether the addition of methylsiloxane (silicone) to butteroil would improve the chemical and physical stability of the butteroil during actual deep fat frying conditions, and whether the storage stability of potato chips fried in siloxanetreated butteroil would be increased. A deep fat frying study was performed using butteroil (BO), butteroil with 10 ppm of silicone (BOS), and a commercial corn oil containing silicone (CO). Potato slices were fried in the oils on a daily basis and evaluated for flavor using a trained organoleptic panel. The storage stability of the chips was also determined by means of the peroxide values and the Schaal oven test. The thermal stability of the oils was determined with the smoke point test, total acid content and nonurea adduct-forming esters (NUAFE). The results of this study showed that the addition of silicone to butteroil unproved its stability by decreasing its total acid content and NUAFE, by raising the smoke point and by lowering the degree of foaming. Also, the flavor of the BOS chips retained their high acceptability and preference over the BO chips. The storage stability of the BOS chips was also improved as shown by lower peroxide values and longer Schaal oven tests during storage.
Effect of (Hydroxypropyl)‐β‐cyclodextrin on Flux of Morphine, Fentanyl, Sufentanil, and Alfentanil through the Spinal Meninges of Monkey

Abstract Previous studies have demonstrated that (hydroxypropyl)‐β‐cyclodextrin behaves as a slow‐release reservoir when used as a vehicle for intrathecal administration of opioids. The goal of the current investigation was to determine if (hydroxypropyl)‐β‐cyclodextrin might serve as a slow‐release vehicle for epidural opioid administration as well. An in vitro diffusion cell model was used to determine the flux of morphine, fentanyl, alfentanil, and sufentanil through the spinal meninges of Macaque nemestrina monkeys in the absence or presence of varying concentrations of (hydroxypropyl)‐β‐cyclodextrin. No concentration of cyclodextrin slowed the flux of any of the opioids through the meninges, indicating that (hydroxypropyl)‐β‐cyclodextrin will not behave as a slow‐release reservoir for these opioids in the epidural space. This finding suggests that the rate‐limiting step in opioid transfer was diffusion through the meninges not dissociation of the opioid cyclodextrin complex. However, (hydroxypropyl)‐β‐cyclodextrin significantly increased the flux of sufentanil through the meninges. Since sufentanil's hydrophobicity has previously been shown to impede its meningeal flux, this finding suggests that cyclodextrin effectively decreases sufentanil's hydrophobicity by formation of inclusion complexes in the aqueous environments of the spinal meninges.
A Risk of Meaning Transfer: Are Negative Associations More Likely to Transfer ThanPositive Associations?

Celebrity endorsement is a common influence tactic used by marketers. By linking their brands with cultural entities such as celebrity endorsers, marketers attempt to acquire positive meanings and personality traits associated with the entity. Entities, however, often have both positive and negative associations. For example, a celebrity can be both smart and arrogant, or sexy and ditsy. We highlight a risk of meaning transfer: negative associations are more likely to transfer to a brand than positive associations. Three studies show that brands are more likely to acquire the negative than the positive personality traits associated with a celebrity endorser and that negative associations transfer even under conditions that inhibit the transfer of positive associations.
Mental health service utilization in children adopted from US foster care, US private agencies and foreign countries: Data from the 2007 National Survey of Adoption Parents (NSAP)

Abstract Aims In this analysis, we (1) described the rate of mental health service utilization for children from domestic foster care adoption, domestic private adoption, and international adoption and (2) analyzed the effect of common risk factors on mental health service utilization. Data As part of the 2007 National Survey on Adoptive Parents (NSAP), parents with children 5–17 years old (N = 1722) were asked if their children had received mental health services and how helpful these services were. Parents also provided data on the children's demographics and likelihood of pre-adoption adversity (e.g., abuse). Results For boys, mental health services were utilized by 52.4% of domestic foster care adoptees, 41.0% domestic private adoptees, and 40.0% of international adoptees. For girls, the corresponding rates were 36.3%, 24.8%, and 30.9% respectively. Parents reported that the services were very helpful for about half of the children. Logistic regression analyses showed that adoptees from domestic foster care were more likely than international adoptees to have received mental health services, but there was no difference between domestic private adoptees and international adoptees. Older age at placement, older age at assessment, having special health care needs, and being male all increased the odds for having received mental health services.
Observations and Orbital Analysis of the Giant White Dwarf Binary System HR 5692

We report spectroscopic observations of the red giant star HR 5692, previously known to be a binary system both from other spectroscopic work and from deviations in the astrometric motion detected by the Hipparcos satellite. Earlier International Ultraviolet Explorer (IUE) observations had shown the presence of a hot white dwarf companion to the giant primary. We have combined our radial velocity observations with other existing measurements and with the Hipparcos intermediate astrometric data to determine a complete astrometric-spectroscopic orbital solution, providing the inclination angle for the first time. We also determine an improved parallax for the system of 10.12 ± 0.67 mas. We derive the physical properties of the primary, and with an estimate of its mass from stellar evolution models (1.84 ± 0.40 M ☉), we infer the mass of the white dwarf companion to be M WD = 0.59 ± 0.12 M ☉. An analysis of an IUE white dwarf spectrum, using our parallax, yields T eff = 30, 400 ± 780 K, log g = 8.25 ± 0.15, and a mass M WD = 0.79 ± 0.09 M ☉, in marginal agreement with the dynamical mass.
The Ethical Leader's Responsibilty to Community

This paper has two purposes. It is a reflection on corporate social responsibility, ethical leadership, and civic responsibility. These subjects were first learned in the classroom through traditional pedagogical methods. However, these traditional methods were supplemented by participation in a service-learning project. My experience working for a community organization provided examples of what I learned in class. This experience also allowed me to make normative claims concerning the duties of corporations, citizens, and ethical leaders. This paper also demonstrates that service-learning projects can provide moral and civic education for students. My fifteen hours of service increased my awareness of community problems, demonstrated that people have a responsibility to help others, and ingrained a commitment to service that will last my entire life. I participated in service learning as part of a requirement for the Ethical Dimensions of Leadership course (MGT 5384) at Virginia Tech. This course focuse...
Binary Interactions between High-Density Polyethylene and 4-(1-Naphthylmethyl)bibenzyl during Low-Pressure Pyrolysis

Low-pressure pyrolysis experiments employing a high molecular weight polymer and a model compound for coal were conducted to address the effect of phase behavior on the overall degradation mechanism and reaction pathways during coprocessing. Thermal degradation of high-density polyethylene (HDPE) and 4-(1-naphthylmethyl)bibenzyl (NBBM) was conducted at 420 °C at different reactant loadings, both neat and in binary mixtures. During binary mixture experiments, there was an enhancement in the selectivities to primary products of NBBM at longer reaction times, with a significant reduction in the formation of secondary and tertiary products. These favorable interactions occurred because the polymer induced diffusion limitations in the system compared to neat NBBM pyrolysis, which minimized NBBM self-interactions and promoted reactions with the surrounding polymer. The degradation pathways of HDPE during binary mixture experiments were similar to those during neat reactions, with slight changes to the product y...
Progressive encephalomyelitis with rigidity responsive to plasmapheresis and immunosuppression

The stiff-man syndrome is reported in a 55-year-old woman who also had signs of severe bulbar musculature hypercontraction. These clinical features correspond to the progressive encephalomyelitis with rigidity syndrome. Diazepam was minimally beneficial, but after treatment with plasmapheresis and corticosteroids, she was still asymptomatic when seen 5 years later.
Proinflammatory cytokines and specific immune function

ng is~ues concerning the relationship between pain, the immune system, and the progression of disease. The general argument is advanced that (1) pain elicits endocrine and autonomic changes, (2) these endo­ crine and autonomic alterations interfere with various aspects of immune function, and (3) this interference with immunity promotes diseases that are normally regulated by immune processes. The specific data considered are focused on surgery and the postsurgi­ cal period as the pain event, natural killer (NK) cell function as the immune process, and the metastatic spread of implanted tumor cells as the disease. The evidence presented does indeed support the conclu­ sions that surgery supresses NK cell function and facilitates the metastatic spread of an implanted NK­ sensitive tumor and that pre- plus postoperative mor­ phine administration mitigates the impact of surgery on these processes. However, the conclusions drawn involve a number of assumptions that deserve men­ tion and discussion. The bulk of the data cited by Page examines the effects of surgery on immune parameters and tumor growth. It is assumed that the impact of surgery on these measures is mediated by the pain produced dur­ ing and following surgery, but surgery alters numerous processes other than pain. Thus the argument requires a demonstration that it is the pain that leads to reduc­ tions in NK cytotoxicity, tumor growth, and so on, rather than some other effect of surgery.