cssi/SciSciGPT-SciSciNet huggingface dataset:
Suicide Ideation: Its Relation to Depression, Suicide and Suicide Attempt.

A random sample of 3,935 adults from a general population were interviewed and asked to report how often they had thoughts of suicide as well as their opinion on the frequency of suicide ideation in others. Depression was found to be related to the respondent's reports of his/her own suicidal thoughts and to reports of frequent suicide ideation in others. A total of 5.4 percent of the respondents reported some degree of suicide ideation in the previous month and 9.1 percent reported that others think about suicide once a month or more. When the demographic characteristics of those who report suicide ideation in themselves or others were compared to those of suicide attempters and committers, some consistencies were found, suggesting that such questions may be useful in identifying those "at risk." Nevertheless, sufficient discrepancies were found which suggest that there may be a number of factors which increase or decrease the likelihood that someone with thoughts of suicide will attempt or commit suicide. Follow-up studies are necessary to uncover such factors and the degrees to which they influence the occurrence of suicide.
Multilayer Insulation (Mli) in the Superconducting Super Collider: A Practical Engineering Approach to Physical Parameters Governing Mli Thermal Performance

Multilayer insulation (MLI) is employed in cryogenic devices to control the heat load of those devices. The physics defining the thermal performance of an MLI system is extremely complex due to the thermal dynamics of numerous interdependent parameters which in themselves contribute differently depending on whether boundary conditions are transient or steady-state. The Multilayer Insulation system for the Superconducting Super Collider (SSC) consists of full cryostat length assemblies of aluminized polyester film, fabricated in the form of blankets, and installed as blankets to the 4.5K cold mass, and the 20K and 80K thermal radiation shields. Approximately 40,000 blankets will be required in the 10,000 cryogenic devices comprising the SSC accelerator. Each blanket will be nearly 56 feet long by 6 feet wide and will consist of as many as 32 reflective and 31 spacer layers of material. Discussed are MLI material choices, and the physical parameters which contribute to the operational performance of MLI systems. Disclosed is a method for fabricating MLI blankets by employing a large diameter winding mandrel having a circumference sufficient for the required blanket length. The blanket fabrication method assures consistency in mass produced MLI blankets by providing positive control of the dimensional parameters which contribute to the MLI blanket thermal performance. The fabrication method can be used to mass produce prefabricated MLI blankets that by virtue of the product have inherent features of dimensional stability, three-dimensional uniformity, controlled layer density, layer-to-layer registration, interlayer cleanliness, and interlayer material to accommodate thermal contraction differences.
Research Summary: Logic Programming for Massively Distributed Systems

My research focuses on finding a better way to program massively distributed systems. Programming these systems is crucial as we move into a world where they are increasingly necessary. Unforunately, existing concurrency models in modern languages are very difficult for programmers to understand and to reason about. Many programmers have an extremely hard time writing and debugging concurrent programs, let alone massively distributed ones. Race conditions, in particular, are among the most challenging bugs to find, understand, and resolve.
Signed Hypergraph Designs and Diagonal Forms for Some IncidenceMatrices

Given a t-uniform hypergraph H on k vertices and an assignment of integers f(T) to thet -subsets T of a v-setX , v\ge k+t, e give necessary and sufficient conditions for the existence of an assignment of integer multiplicities h(G) to those subhypergraphs G of the complete t-uniform hypergraph on v vertices that are isomorphic to H so that the sum of the integers h(G) over those G that contain T is f(T). Our main theorem is stated in terms of integral matrices. As a consequence of our main theorem, e also determine a diagonal form, and hence the p-rank for all primes p, for the incidence matrix of t-subsets versus subhypergraphs isomorphic to H.
Function, disability, and psychological well-being.

Disability research in arthritis, as in disability research in general, has focused on functional limitations and activities of daily living/instrumental activities of daily living (ADL/IADL) disabi
MPI Collective Operations over IP Multicast

Many common implementations of Message Passing Interface (MPI) implement collective operations over point-to-point operations. This work examines IP multicast as a framework for collective operations. IP multicast is not reliable. If a receiver is not ready when a message is sent via IP multicast, the message is lost. Two techniques for ensuring that a message is not lost due to a slow receiving process are examined. The techniques are implemented and compared experimentally over both a shared and a switched Fast Ethernet. The average performance of collective operations is improved as a function of the number of participating processes and message size for both networks.
Social Sequence Analysis: Methods and Applications

Part I. Introduction: 1. Sequence analysis in the social sciences Part II. Theoretical Background: 2. Theoretical foundations of social sequence analysis Part III. Social Sequence Analysis Concepts and Techniques: 3. Sequence analysis concepts and data 4. Detecting sequence structure 5. Whole-sequence comparison methods Part IV. New Directions in Social Sequence Analysis: 6. Network methods for sequence analysis 7. Social microsequence analysis Part V. Conclusions: 8. The promise of social sequence analysis.
Xenon Shock Waves Driven by High Magnetic Fields

Magnetic fields in the range 0.2 – 2.0 MG produce shocks in 0.1 – 1.0 atmosphere xenon gas which have shock mach numbers as high as 100. Using pulsed x-ray and other diagnostics, our studies of velocity, compression, and luminosity are in good agreement with a simple snowplow theory. In some of the experiments, ultraviolet radiation from the shocked xenon produces luminous precursors and interactions with the metal walls of the shock tube. The addition of an ultraviolet absorbing organic impurity vapor diminishes the amplitude of these effects. A clean, chemically inert metal wall is even more effective. Further experiments show that magnetic shear has a stabilizing effect on the current-carrying layer of the shocked gas. We conclude that a megagauss magnetic field is a useful shock tube driver for producing high velocity shock waves.
Analysis of Slip Behavior in a Single Shear Lap Lead-Free Solder Joint During Simple Shear at 25°C and 0.1/s

The relative activity of the potential slip systems in Sn is examined by comparing an experiment of a single shear lap deformation with simulations using the viscoplastic self-consistent crystal plasticity model developed by Lebensohn and Tome. In a single shear lap specimen made using eutectic Sn-Ag solder on copper pull tabs, the initially polished side was characterized using orientation mapping before and after 0.8 shear deformation at 25°C at a shear strain rate of 0.1/s. The critical resolved shear stress of potential slip systems and the rate sensitivity was altered by trial and error until good agreement between experimentally observed and computed texture was obtained. This result indicated that slip on {101) and {211) planes is much more difficult to activate than on other slip systems for the grain orientations present in this sample. This particular sample showed much activity on the {010)〈101] slip system, but the activation of this slip system may be related to the initial dominant orientation in the specimen. This result is compared with literature and related experiments on ball grid arrays in a companion paper in this volume that show similar trends. As lead-free solder joints are commonly single crystals or multicrystals, this particular result is not indicative of lead-free solder joints as a whole, but must be interpreted in the context of a larger data set.
An electron microscope heteroduplex study of the ribosomal DNAs of Xenopus laevis and Xenopus mulleri

Abstract The arrangement of the genes and spacers has been analyzed in ribosomal DNA of Xenopus laevis and Xenopus mulleri by heteroduplex mapping and visualization of ribosomal RNA-DNA hybrids. Heterologous reassoeiated molecules show a characteristic pattern in which two perfectly duplexed regions, whose lengths are those predicted by the known lengths of the 18 S and 28 S genes, are separated by a small substitution loop of about 0.23 × 106 daltons and a large region of partial homology which averages 3.24 × 106 daltons. These mismatched regions are entirely consistent with the known sequence divergence previously described (Brown et al., 1972) for the transcribed and non-transcribed spacer regions of the two rDNAs, respectively. Hybrids of X. laevis rDNA with 18 S and 28 S rRNA contain two duplex regions of the expected lengths for the 18 S and 28 S genes separated by 0.49 × 106 daltons of single-strand DNA. This latter value is the length of the transcribed spacer region between the 18 S and 28 S RNAs that has been measured within the 40 S RNA precursor molecule by secondary structure mapping (Wellauer & Dawid, personal communication). There is also a longer single-strand region separating one 18 S + 28 S gene set from the next; this is considered to be mainly non-transcribed spacer. We conclude that the 18 S and 28 S genes are separated by about 0.5 × 106 daltons of DNA of which about half is homologous in the two Xenopus species. This region is part of the transcribed spacer. In addition, the longer non-transcribed spacer can be seen to have some homology between the two species; the location of this homology is fairly reproducible between molecules and has been carefully documented by contour length measurements.
Graph groups are biautomatic

Abstract Graph groups admit a (finite) presentation in which each relation is of the form xy = yx for generators x and y . While the two extreme cases of graph groups, free groups and free abelian groups, have been previously shown to be bicombable (in fact, biautomatic), neither of the normal forms typically used for the combings generalize successfully to arbitrary graph groups. The normal forms presented here which do yield results for arbitrary graph groups utilize the concept of a “commuting clique” of generators, and when these normal forms are applied to free abelian groups, they differ from the “usual” normal forms. As the set of normal forms is a regular language over the free monoid on the set of generators and their formal inverses, it follows that graph groups are biautomatic.
Thioketone complexes of chromium, molybdenum, and tungsten carbonyls

Abstract A series of thioketone complexes of the type M(CO) 5 (S=CR 2 ), where M = Cr, Mo or W, and R = Me, Et or Ph, have been prepared by the reaction of M(CO) 5 I − with Ag + in the presence of the ketone (O = CR 2 ) and H 2 S. Coordination to the metal stabilizes thioketones such as thioacetone which, otherwise, is unstable and polymerizes rapidly. Infrared, 1 H and 13 C NMR spectra of the compounds are consistent with the ligands being coordinated through the sulfur atom. The W(CO) 5 (S=CR 2 ) complexes react with MeCN, I − , N 3 − and C 6 H 11 NH 2 (in CCl 4 ) to give the thioacetone-displaced products, W(CO) 5 L. With C 6 H 11 NH 2 in pentane, another product is obtained which apparently results from amine addition to the thioketone ligand. This compound reacts with MeI and Et 3 O + to give the dialkyl sulfide complexes, W(CO) 5 (SMe 2 ) and W(CO) 5 (SEt 2 ).
Quantum Dot Research: Current State and Future Prospects

ABSTRACT This article reviews the current state of research involving semiconductor quantum dots, provides a brief review of the theory behind their unique properties, and an introduction explaining the importance of quantum dot research. The characteristic shifting of the band gap energy with quantum dot size, as predicted from the density of states for low-dimensional structures, allows experimental measurements to determine the extent to which quantum confinement effects play a role in the resulting properties. A few of the current techniques used to measure the presence and physical characteristics of quantum dots and their energy levels is reviewed, including transmission electron microscopy, optical transmission, and Raman and photoluminescence spectroscopy. Finally, some of the more exciting applications for quantum dots currently being researched for use in the field of optoelectronics are reviewed, including quantum dot infrared photodetectors, quantum dot lasers, and quantum dot solar cells. Com...
The Determinants of Off-Budget Activity of State and Local Governments

The primary finding of this paper is that the off-budget activity of the public sector is significantly and positively related to on-budget activity by state and local governments. We suggest the following policy implications. One, there appears to be evidence that the composition of total government activity is related to the relative costs of the alternative avenues of providing governmental activity. Future research into determining the nature of the relative cost differences may be one useful means of understanding both the composition of government activity as well as its total size. Two, our ability to measure the “true” size of public sector participation in the economy must go well beyond our attempt here. While we have presented information on one of the important “hidden” elements of public sector participation, we are still a long way from effectively incorporating similar data on legislation, regulations and so forth into our empirical tests. Further research into these issues is clearly warranted.
A survey of current techniques in veterinary electrodiagnostics: EEG, spinal evoked and brainstem auditory evoked potential recording

A questionnaire on the techniques being used to record electroencephalograms, spinal evoked potentials and brainstem auditory evoked potentials was mailed to 34 neurologists at veterinary colleges and board certified veterinary neurologists in private practice in the United States and Canada. Nineteen replies (56%) were returned. A summary of the questionnaire is provided, which indicates the diversity of electrodiagnostic techniques currently used.
Conformational studies of imiloxan and imiloxan cation using AM1 and PM3 semiempirical molecular orbital methods

Abstract Conformational studies of the α 2B adrenergic receptor antagonist, imiloxan, were performed using the AM1 and PM3 semiempirical molecular orbital methods. Although the two methods gave similar results, crucial differences were observed. The energy-bond rotation profiles were similar for the two molecular orbital methods, but small differences in these calculations produced substantial differences in the conformers found at the various energy minima. Electrostatic interactions between the imidazoline nitrogens and the dioxane oxygens are decisive in determining the Conformational stability of both the cation and the neutral molecule. The differences between the hamiltonians were apparent in calculations involving the charged cation where the electrostatic interactions stabilize certain conformations and the neutral molecule where the electrostatic interactions are repulsive. Calculations using the AM1 hamiltonian favored conformers with a hydrogen bond, whereas the PM3 calculations gave both nitrogens a positive charge and would favor those conformers in which either one or the other nitrogen was close to the negative oxygen. Although the free base is electrically neutral, the stable conformers showed the importance of the electrostatic interactions caused by the asymmetrical charge distribution around the hetero atoms. Comparison of the molecular orbital structures with the experimental X-ray structure showed that the experimental structure corresponded with a theoretical conformer found at one of the local energy minima rather than the structure found at the global minimum. Imiloxan has a number of conformers at low energy local minima with energies near the global minimum. Therefore, the appearance of a local rather than global minimum energy structure as the X-ray structure is not surprising. These studies demonstrated that electrostatic interactions will likely play an important role in the drug-receptor complex responsible for the pharmacological activity of imiloxan.
Schiff base chelate-functionalized organoclays

Abstract An amine-functionalized layered magnesium silicate (Mg-APTES) was prepared by direct alkaline co-polymerization between magnesium chloride and 3-aminopropyltriethoxysilane. Solid state 13 C and 29 Si NMR and elemental analyses reveal a partial condensation of the framework precursors. The X-ray diffraction pattern shows a disorganized talc-like structure with a basal spacing consistent with the presence of interdigitated and slightly titled organic moieties in the interlayer galleries. The surface primary amines of Mg-APTES were further reacted separately with several aldehydes (salicylaldehyde, 5-chlorosalicylaldehyde, 2-pyridine carboxyaldehyde) and one ketone (acetylacetone) in order to form Schiff base chelating ligands with O- and N-donor groups incorporated in the layer surface. The successful formation of the chelating groups on the surface was determined by the observation of imine IR vibration bands in the 1600–1645 cm −1 range, and confirmed by solid state 13 C NMR. Powder X-ray diffraction patterns of the Schiff base-modified compounds show that the layered structure is maintained with an expansion of the interlayer space consistent with the steric size of the chelating groups. Transition metal ions (Cu 2+ , Ni 2+ , Co 2+ ) were incorporated into the chelate-modified organoclays. The UV–visible and ESR data of a representative sample prepared by Cu 2+ ion complexation correlate reasonably well with those of the analogous Cu(II)Salpn complex (Salpn = bis(salicylidene)propylendiamine), indicating the formation of anchored Schiff base-type complexes.
Ontogeny of the hyobranchial apparatus in the salamanders Ambystoma talpoideum (Ambystomatidae) and Notophthalmus viridescens (Salamandridae): The ecological morphology of two neotenic strategies.

Comparison of metamorphosis of skull and hyobranchial system in two species of neotenic salamanders reveals two different types of neoteny. Ambystoma talpoideum is completely neotenic owing to delayed metamorphosis. Notophthalmus viridescens exhibits limited neoteny as a result of incomplete metamorphosis. Morphological details of neoteny are compared to life history in both species in order to discuss the ecological morphology of the two neotenic strategies. Comparisons to Taricha granulosa, Triturus vulgaris, and Ambystoma gracile indicate that these two strategies are widely employed and may represent familial patterns.
Obesity stigma in sexual relationships.

Obese children are stigmatized in same-sex relationships. This study examines whether, in adulthood, obesity stigma exists in adults when they are asked to rank order preferences for a sexual partner. Following the methods of Richardson et al. (Richardson SA, Goodman N, Hastorf AH, Dornbusch SM. Cultural uniformity in reaction to physical disabilities. Am Sociol Rev. 1961;26:241ﾖ247) and Latner and Stunkard (Latner J, Stunkard AJ, Wilson GT. Age, ethnic and gender differences in stigmatization of obesity. Orlando, FL: International Conference on Eating Disorders; 2004), 449 college students were asked to rank order six drawings of potential sexual partners. The drawings included an obese partner, partners with various other disabilities, and a healthy partner. The least-preferred partners were obese. Men, compared with women, provided significantly lower ranks for obese partners Overall, despite the fact that the majority of adults in the U.S. are overweight, discrimination on the basis of weight occurs in making a choice of a sexual partner.
Epigenetic regulation of Th1 and Th2 cell development.

All cells of the body, regardless of the tissue type, contain the same genetic material, but express this genetic material differently. Epigenetics is one process by which differential gene expression within a cell is regulated. Epigenetic mechanisms involve postsynthetic modifications to DNA and/or DNA-associated histones that do not change the DNA sequence itself, but which remodel chromatin, are passed along at each cell division, and occur during and after early development. The CD4+ T cell best represents a cell in which epigenetic mechanisms are used to affect mature cell physiology. As a naive CD4+ T cell develops into either a Th1 or Th2 cell that secretes predominantly IFN-gamma or IL-4, respectively, the expression of one cytokine gene and the permanent silencing of the other is orchestrated using epigenetic mechanisms. Because there appears to be an association between Th1/Th2 cell immunity, behavior, and/or disease, it is possible that an environmentally induced epigenetic change that occurs during Th1/Th2 cell development could explain how certain Th1/Th2-associated conditions develop. This article will review basic epigenetic mechanisms and what is known about how these mechanisms influence cytokine gene expression in a naive CD4+ T cell as it develops into a Th1 or Th2 cell.
The commercial use of conifer rooted cuttings in forestry: a world overview.

Conifer reforestation programs have traditionally been carried out using natural seeding, direct seeding or, more recently, planting with nursery-grown stock. Only within the past decade have rooted cuttings found use in large scale commercial operations. To assess the current status of this technology questionnaires were developed and mailed to 50 individuals and organizations around the world. The questionnaires were designed to collect information on: (1) annual production by region and species, (2) objectives of rooted cutting programs, (3) production procedures, (4) field performance of cuttings as compared to seedlings, and other topics.
UN Development Programme and non-communicable diseases

In her Comment (Feb 16, p 510), Helen Clark from the UN Development Programme (UNDP) has overlooked the problematic association between development agencies and the tobacco industry, which continually undermines global efforts to combat noncommunicable diseases (NCDs). The tobacco industry promotes sale and consumption of addictive and disease-causing substances that fuel NCDs. Its stated and vested interests are directly opposed to public health priorities. Because of a lack of adherence to exclusion criteria and standards for partnerships, such companies largely responsible for causing the NCD epidemic have ironically become development partners of UN agencies. The Global Environment Facility (GEF), an initiative of the UNDP (and the World Bank), led projects in the Philippines, Panama, Uganda, and Tanzania, which received funds from tobacco companies. In Tanzania, GEF supported an aff orestation programme to sustain tobacco farming. Partners, such as Global Business Coalition on Health and UN Global Compact, partner with corporations in the tobacco industry. The openness of the UN systems confers upon the tobacco industry an undeserved legitimacy, facilitates its access to global policy making, and ultimately distorts health priorities. UNDP’s agenda to combat NCDs is thus called into question by its partnership with an industry that contributes overwhelmingly to the crisis.
Ependymoneuronal specializations between LHRH fibers and cells of the cerebroventricular system.

Light-and electron-microscopic immunocytochemistry (LM-ICC and EM-ICC) were used to visualize luteinizing hormone-releasing hormone (LHRH) in fibres associated with ventricular ependyma and tanycytes of the median eminence. LM-ICC suggests that LHRH fibers appear to enter the third ventricle. However, with EM-ICC, LHRH fibers are in fact found within ependymal canaliculi formed by adjacent ependymal cells. The canaliculi contain other myelinated and unmyelinated axons in addition to immunoreactive LHRH fibers. Thin slips of ependymal and tanycyte processes project into the canaliculi and enclose axons to varying degrees. At the median eminence many LHRH fibers bend sharply downwards from their ventricular course and travel with tanycytic processes towards their common destination — the perivascular space of the hypophysial-portal vascular system. Here, EM-ICC reveals that LHRH fibers closely contact basal processes of tanycytes. Lateral processes from tanycytes form glioplasmic sheaths which surround some individual LHRH fibers. A few LHRH terminals contact the perivascular space directly but more often are separated from the perivascular space by intervening glia. It is hypothesized that: (1) glia of this region responds to the physiological state of the animal and may determine the degree of LHRH secretion by varying the extent of glial investment of LHRH terminals; and (2) may play a role during development by providing direction and support for LHRH fibers similar to that described for radial and other glial cells.
Disorders of wound healing

The healing wound offers a variety of potential end results. The surgeon's responsibility is to define what he wants and then arrange to get it. History has proved that technical improvements can eliminate disorders such as dehiscence and incisional hernias. Technical improvements should diminish the frequency of failed tendon repairs.
Shock Wave Induced Decomposition of RDX: Quantum Chemistry Calculations

Quantum chemical calculations on single molecules were performed to provide insight into the decomposition mechanism of shocked RDX. These calculations complement time-resolved spectroscopy measurements on shock wave compressed RDX crystals (previous paper, this issue). It is proposed that unimolecular decomposition is the primary pathway for RDX decomposition in its early stages and at stresses lower than approximately 10 GPa. This decomposition leads to the generation of broadband emission from 350 to 850 nm. Chemiluminescence from (2)B1 and (2)B2 excited states of NO2 radicals is associated with a major portion of the experimentally observed emission spectrum (>400 nm). The remaining portion (<400 nm) of the emission spectrum primarily results from excited HONO intermediates. It is proposed that for stresses higher than 10 GPa, bimolecular reactions between radical decomposition products and unreacted RDX molecules become the dominant pathway. This radical assisted homolysis pathway is cyclic and leads to the acceleration of decomposition, with increased production of low energy NO2 radicals. These radicals produce emission that is stronger in the long wavelength portion of the spectrum. Finally, a comprehensive chemical decomposition mechanism is put forward that is consistent with the experimental observations of shock-induced emission in RDX crystals.
Domain within Herpes Simplex Virus 1 Scaffold Proteins Required for Interaction with Portal Protein in Infected Cells and Incorporation of the Portal Vertex into Capsids

The portal vertex of herpesvirus capsids serves as the conduit through which DNA is inserted during the assembly process. In herpes simplex virus (HSV), the portal is composed of 12 copies of the U L 6 gene product, pU L 6. Previous results identified a domain in the major capsid scaffold protein, ICP35, required for interaction with pU L 6 and its incorporation into capsids formed in vitro (G. P. Singer et al., J. Virol. 74:6838-6848, 2005). In the current studies, pU L 6 and scaffold proteins were found to coimmunoprecipitate from lysates of both HSV-infected cells and mammalian cells expressing scaffold proteins and pU L 6. The coimmunoprecipitation of pU L 6 and scaffold proteins was precluded upon deletion of codons 143 to 151 within U L 26.5, encoding ICP35. While wild-type scaffold proteins colocalized with pU L 6 when transiently coexpressed as viewed by indirect immunofluorescence, deletion of U L 26.5 codons 143 to 151 precluded this colocalization. A recombinant herpes simplex virus, vJB11, was generated that lacked U L 26.5 codons 143 to 151. A virus derived from this mutant but bearing a restored U L 26.5 was also generated. vJB11 was unable to cleave or package viral DNA, whereas the restored virus packaged DNA normally. vJB11 produced ample numbers of B capsids in infected cells, but these lacked normal levels of pU L 6. The deletion in U L 26.5 also rendered pU L 6 resistant to detergent extraction from vJB11-infected cells. These data indicate that, as was observed in vitro, amino acids 143 to 151 of ICP35 are critical for (i) interaction between scaffold proteins and pU L 6 and (ii) incorporation of the HSV portal into capsids.
Major histocompatibility complex class I-dependent skewing of the natural killer cell Ly49 receptor reportoire

Subsets of mouse natural killer (NK) cells express receptors encoded by the Ly49 gene family that recognize allelic determinants on major histocompatibility complex (MHC) class I molecules. Recognition of self class I molecules typically inhibits NK cell lytic function. The presence of NK cell subsets expressing receptors which are able to discriminate class I alleles raises the possibility that there exist mechanisms to coordinate the NK cell receptor repertoire with the class I molecules of the host. In the present study, we determined the effects of class I gene expression on the frequencies of NK cells expressing three different Ly49 receptors defined by monoclonal antibodies. We show here an MHC-dependent skewing of NK cell subsets expressing multiple Ly49 receptors with specificity for self MHC. The results provide the first evidence that the frequencies of NK cells expressing different Ly49 receptors are determined by the host's MHC molecules. The results also extend previous findings that MHC class I expression influences the cell surface levels of each Ly49 receptor, suggesting an additional mechanism by which MHC molecules may influence the effective specificity of NK cells. Models to account for self tolerance and MHC-controlled repertoire differences are discussed.
A general solution for an unsteady linear diffusion problem

An explicit solution of elementary nature is derived for a mixed initial/boundary value problem concerning the two-dimensional diffusion equation, given an arbitrarily assigned behaviour along a semi-infinite line and a vanishing normal derivative along the remainder of the line; and the physically significant variation of the normal derivative at the boundary is similarly expressed.
Developments in environmental performance simulation

Performance simulation in architectural design has been rapidly evolving over the past decade. Simulation tools have become widely available and this has had a measurable influence on the way in which buildings are being designed, analyzed and constructed. Several new approaches for the development of these tools are emerging, some of which evolved through many years of work based on the area of building simulation. This paper reviews these developments in environmental digital performance simulation as it relates to architectural design. It describes the recent research, development and use of these environments as well as some of the challenges that exist.
Purposes of AAC device use for persons with ALS as reported by caregivers.

Thirty-four informal caregivers who support 26 persons with ALS reported on AAC technology use. Each caregiver completed the Communication Device Use Checklist, a survey tool developed for this stu...
State-of-the-Art Review: Thrombophilia and Pregnancy: Review of the Literature and Some Original Data

The association of thrombophilia with pregnancy complications has received increasing attention. It is now apparent that thrombophilia is responsible for a large number of the serious complications of pregnancy such as venous thrombosis, pulmonary embolism, fetal loss, pregnancy loss, intrauterine fetal demise, and preeclampsia. The inherited thrombophilia abnormalities, factor V Leiden mutation, prothrombin gene mutation 20210A, and antithrombin III, protein C, and protein S deficiency, and the acquired disorders, the anticardiolipin syndrome and lupus inhibitor, are responsible for a large share of the incidences of premature termination of pregnancy and many of the above complications. The normal physiology of pregnancy may be prothrombotic, with evidence for increased markers of activated coagulation and coagulation factors. There is a decrease in protein S and resistance to activated protein C occurs in a significant number of pregnancies in the absence of the factor V Leiden mutation. In the following article, we review some of the major studies that have correlated the thrombophilia and other acquired disorders that adversely impact pregnancies.
RESPIRATORY RATES OF MIGRATING ZOOPLANKTON IN THE NATURAL HABITAT

Rates of oxygen consumption by zooplankton in Cayuga Lake were measured when the lake was stratified. The effects of temperature, pressure, and light wcrc examined. Animals from the epilimnion, mostly cladocerans, and from the hypolimnion, mostly copepods, respired at similar rates in their rcspectivc habitats. When the animals were placed in the same habitats, copepods from the hypolimnion hacl the greater rates of respiration. Copepods, which migrated over an extensive vertical distance daily, were less sensitive to changes in depth than wcrc claclocerans, which remained within a narrow vertical range. The copepods were less affectccl by changes in pressure and temperature within than outside their range of migration.
Time-varying betas and volatility persistence in International Stock markets

Abstract This paper investigates the degree of volatility persistence and the time-varying behavior of systemic risk (beta) for ten international stock markets. The findings suggest that small capitalization markets exhibit considerably higher volatility persistence than large capitalization markets. Market betas with respect to a value-weighted world index are time-dependent for many of the markets examined. Interestingly, markets with high volatility persistence possess higher systematic risk during periods of high world market volatility.
Atmospheric oxygen in Mn doped GaAs/GaAs(0 0 1) thin films grown by molecular beam epitaxy

Mn doped GaAs thin films were grown using molecular beam epitaxy at high and low substrate temperatures. The elemental concentration depth profiles in the thin films were determined by using Auger electron spectroscopy combined with ion etching. The Mn concentration is higher near the surface and then decreases with depth for films grown at high substrate temperatures. The Mn concentration profile is much more uniform when films are grown using a low substrate temperature. What was unexpectedly found are high levels of oxygen in the low substrate temperature grown thin films.
Comment on "Consumer Risk Response and Consumer Protection: An Economic Analysis of Seat Belt Usage"

Rachel Dardis's article [ref below] is an important and useful cost-benefit analysis of seat belt usage by consumers. Finding a divergence between the social and private benefits of wearing seat belts demonstrates the presence of externalities in the seat belt issue. The fact that only 13 percent of Americans wear seat belts, perhaps, can be explained by consumer ignorance and irrationality, and also, to a limited degree by insurance coverage of some accident costs. Dardis, however, suggests that it may be rational for drivers of large cars not to wear seat belts, if their implicit user costs of wearing seat belts amounted to $104 per year. Although Dardis stated that this result held for risk averse consumers, I will show that the result depends on the degree of risk aversion that consumers have. For a wide variety of safety issues, divergence between private and social costs can be used as a justification for government regulation of safety. It is, therefore, important to ascertain what is rational for individual consumers. If rational behavior for individuals is consistent with optimal behavior considering all social costs and benefits, then the informed buyer approach [2, p. 245] might be an effective alternative to mandatory product standards. Dardis used a utility analysis approach and discussed the difference between a risk-averting and a risk-seeking individual in maximizing expected utility. This approach could have provided additional insight into the issues discussed by Dardis, but she dropped the concepts of risk-seeking and risk-averting utility maximization after the theoretical discussion and only applied her empirical analysis to maximization of expected wealth. One of Dardis's conclusions-that the decision by drivers of large cars not to use seat belts is consistent with risk aversion-was not proven by the analysis. The rest of this comment presents a simplified hypothetical example of maximization of expected utility for a class of utility functions ranging from risk seeking to extreme risk averting. The problems of applying utility analysis to Dardis's empirical analysis will be described, and implications will be discussed. Dardis, R., "Consumer Risk Response and Consumer Protection: An Economic Analysis of Seat Belt Usage," Journal of Consumer Affairs 1983; 17 (2): 245-261.
Computationally convenient optimal intertemporal portfolios under linear constraints

Abstract This paper considers the normative question of how to obtain computationally convenient optimal intertemporal portfolios under assumptions that are as realistic as possible. In each period expected utility of final-period wealth is maximized, possibly subject to linear inequality constraints. Random net portfolio additions are permitted. Return distributions can evolve deterministically. Under certain assumptions the portfolio problem is shown to be computationally straightforward. Intertemporal properties of the portfolio sequence, including the time path of the portfolio fraction held in risky assets collectively, are discussed.
A cognitively based methodology for evaluating human performance in the computer-aided design task domain

Abstract This article describes a methodology for evaluating human performance in the computer aided design (CAD) task environment. The methodology is based primarily on cognitive theoretic frameworks that are consistent with processes presumed to underlie human design activities. The motivation for its development stems from rapid software and hardware advances in CAD systems and our relative lack of understanding of how these enhancements affect human design performance for (1) fundamentally different types of tasks and (2) different levels of complexity for a particular task. This methodology is currently being applied to computer aided architectural design, an area where artificial intelligence (AI), enhanced geometric modelling and other system features are being debated in terms of their usefulness in aiding the human's design activities.
Identification of a Novel Member (GDF-1) of the Transforming Growth Factor-β Superfamily

A cDNA clone encoding a new member (designated GDF-1) of the transforming growth factor-β (TGFβ) superfamily was isolated from a library prepared from day 8.5 mouse embryos. The nucleotide sequence of GDF-1 predicts a protein of 357 amino acids with a mol wt of 38,600. The sequence contains a pair of arginine residues at positions 236–237, which is likely to represent a site for proteolytic processing. The C-terminus following the presumed dibasic cleavage site shows significant homology with the known members of the TGFβ superfamily, matching the other family members at all of the invariant positions, including the seven cysteine residues with their characteristic spacing. GDF-1 is most homologous to Xenopus Vg-1 (52%), but is not likely to be the murine homolog of Vg-1. In vitro translation experiments were consistent with GDF-1 being a secreted glycoprotein. Genomic Southern analysis indicated that GDF-1 may be highly conserved across species. These results suggest that GDF-1 is most likely an extracel...
Aging and CD8+ T cell immunity to respiratory virus infections.

The capacity of the immune system to mediate effective immune responses to pathogens declines with age. In the case of immune responses to newly encountered antigens, several studies have demonstrated that this decline reflects both a loss of naive T cells and changes in the repertoire and function of these cells over time. However, comparatively little is known about the impact of age on established memory T cells pools. Here we discuss age-related changes in memory CD8+ T cell pools elicited by influenza and parainfluenza viruses and the impact of these changes on immunity in general.
Estimation of Nonaqueous Phase Liquid−Water Interfacial Areas in Porous Media following Mobilization by Chemical Flooding

At hazardous waste sites, removal of contaminant nonaqueous phase liquids (NAPLs) by mobilization using surfactant and cosolvent flushing is an attractive remediation option. Study of the changes in NAPL saturations (S n ) and specific NAPL-water interfacial areas (a nw ) before, during, and after the remediation process is essential in the characterization of waste sites, design, and evaluation of remediation strategies and risk assessment. Empirical indices, such as the capillary number (N Ca ) and, recently, the total trapping number (N T ), were presented in the literature to describe mobilization. Methods available for the measurement of S n allowed an adequate characterization and modeling of the S n -N Ca relationship. In contrast, no methods were available to measure a nw , and hence, no attempts to estimate or model the a nw -N Ca were reported. In the current work, the a nw -N T relationship was experimentally evaluated, using the recently reported interfacial tracers (IFTr) technique to estimate a nw and surfactant-flushing as a means of mobilization. It was found that, following mobilization of residual decane using AOT-100 surfactant, a nw initially remained insensitive to increase in N T , decreased passing through a minimum, and finally increased a with further increase in N T . This final increase is possible due to droplet dispersion or emulsification. A simple analytical model to describe the same relationship also is presented. The methods and results presented can be used as a basis for future investigations of changes in a nw following chemical flooding.
DETERMINATION OF THE FLUORIDE DISTRIBUTION IN RABBIT BONE USING INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS

An instrumental neutron activation analysis (INAA) technique, based on the19F(n,λ)20F reaction, has been development for the determination of fluoride in bone. The purpose was to study fluoride distribution in different kinds of bone samples using a rabbit model. The rationale for the study stems from the posible correlation between fluoride in bone and osteoporosis. The sodium concentration in the bone was used to correct the20F peak area for the23F(n,α)20F contribution. Two secondary standards, teflon tape and teflon coated dacron line, were used to quantify fluoride concentration. They proved to be stable and consistent with respect to their fluoride concentration. Bone specimens from 10 sites and two tooth samples were analyzed for fluoride. Fluoride concentration ranged from 305 ppm in the tibia long bone to 585 ppm in the humerus trochanter end and the magnitude of fluoride concentration levels is age depdentent. The detection limit of the fluoride is approximately 5 ppm using a 100 mg bone sample.
The beholder's share in the perception of orientation of 2-D shapes.

A considerable amount of research demonstrates that people perceive cardinal orientations (horizontal and vertical) more accurately than other orientations; this is termed theoblique effect. We investigated the interaction of this effect with the degree of elongation of the stimulus. Our stimuli were ellipses with a wide range of aspect ratios, varying from a circle (aspect ratio = 1) to a line (aspect ratio = 123.5). The task was to set a probe line in the same orientation as the long axis of the ellipse. In our first experiment, we determined that performance is degraded as the aspect ratio decreases; furthermore, the bias and response variability are linearly related to a transformation of aspect ratio (roundness). We found significant individual differences; the results show high within-subjects correlations and low between-subjects correlations. In our second experiment, we had observers judge the orientation of circles randomly mixed in with ellipses of low aspect ratio. The observers demonstrated intrinsic preferences and generated reproducible distributions of orientation settings with idiosyncratic profiles. These distributions predict the influence on the response to ellipses with an aspect ratio higher than one and can be considered as thebeholder’s share in the perception of shape orientation.
Human Rights Forum: Remembering Japanese-American Internment

: Gretchen E Schafft is contributing editor of “Human Rights Forum,” the AAA Committee for Human Rights column in Anthropology News.
The Vatican to Vegas: A History of Special Effects by Norman M. Klein (New York and London: The New Press, 2004)

This is an extraordinary book in many respects. First, its scope is breathtaking: Norman M. Klein has undertaken nothing less than a history of what we moderns sweepingly call “special effects” but...
Sequential structural changes in the fat body of the tobacco hornworm, Manduca sexta, during the fifth larval stadium

Light and electron microscopy revealed a series of structural changes that occur in the fat body of the tobacco hornworm, Manduca sexta, during the fifth, i.e. the final, larval stadium. At each developmental stage studied, the cells of the fat body were homogeneous in structure. We found no evidence suggesting the presence of more than one type of fat body cell. Our structural data are consistent with published observations on biochemical activities of M. sexta fat body at particular developmental stages. Specific points of agreement include: (a) acquisition of Golgi complex (GC) and rough endoplasmic reticulum (RER) concomitant with the time of major protein production; (b) loss of many cellular organelles (such as GC and RER) as protein production drastically decreases; (c) accumulation of protein granules and urate granules after the onset of wandering (i.e. during the pre-pupal period); (d) accumulation of lipid and glycogen throughout the feeding period. In addition we found that (a) the plasma membrane reticular system (PMRS) developed during the period when protein secretion was great; (b) the PMRS was lost abruptly at the onset of wandering; and (c) the nucleus changed in shape from being roughly spherical to elliptoid in the pre-pupal stage. We found that the structure of M. sexta fat body is similar to that published for other Lepidoptera. However, it differs from that of Heliothis zea in that regional differences are not obviously apparent.
A Case for Watching the Watchdogs

This article was downloaded by: [University of Texas Austin]On: 10 August 2010Access details: Access Details: [subscription number 918552270]Publisher RoutledgeInforma Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK