cssi/SciSciGPT-SciSciNet huggingface dataset:
Adenylate cyclase toxins from Bacillus anthracis and Bordetella pertussis. Different processes for interaction with and entry into target cells

Adenylate cyclase (AC) toxins produced by Bacillus anthracis and Bordetella pertussis were compared for their ability to interact with and intoxicate Chinese hamster ovary cells. At 30 degrees C, anthrax AC toxin exhibited a lag of 10 min for measurable cAMP accumulation that was not seen with pertussis AC toxin. This finding is consistent with previous data showing inhibition of anthrax AC toxin but not pertussis AC toxin entry by inhibitors of receptor-mediated endocytosis (Gordon, V. M., Leppla, S. H., and Hewlett, E. L. (1988) Infect. Immun. 56, 1066-1069). Treatment of target Chinese hamster ovary cells with trypsin or cycloheximide reduced anthrax AC toxin-induced cAMP accumulation by greater than 90%, but was without effect on pertussis AC toxin. In contrast, incubation of the AC toxins with gangliosides prior to addition to target cells inhibited cAMP accumulation by pertussis AC toxin, but not anthrax AC toxin. To evaluate the role of lipids in the interaction of pertussis AC toxin with membranes, multicompartmental liposomes were loaded with a fluorescent marker and exposed to toxin. Pertussis AC toxin elicited marker release in a time- and concentration-dependent manner and required a minimal calcium concentration of 0.2 mM. These data demonstrate that the requirements for intoxication by the AC toxins from B. anthracis and B. pertussis are fundamentally different and provide a perspective for new approaches to study the entry processes.
Extracting effective functional tests from commercial programs

We describe a tool and methodology for extracting short and effective functional tests from long running commercial programs and manufacturing system tests for testing microprocessors and SOCs. The tool combines fast Instruction Set Architecture (ISA) simulator and Design for Test (DFT) capabilities of the microprocessor to enable tracing of long running workloads. The trace is then converted into short functional test programs that can be replayed back in silicon. The tool can extract test programs from BIOS, operating systems, application programs and long running manufacturing system test programs. Using data from silicon experiments on recent microprocessor products, we show that the short tests extracted with our tool was able to screen the defective units as effectively as the original long running application with 6X to 15X reduction in test time.
Women During Midlife: Is It Transition or Crisis?

Increased longevity has expanded the period known as midlife. During midlife, women tend to experience changes in health and family roles that can lead to increased stress and/or depression or alternatively to feelings of well-being. The purpose of this paper was to review the research on women at midlife. The review of literature revealed several smaller studies and one large comprehensive study, the Melbourne Study, which was a 10-year longitudinal study conducted in Australia. The authors suggest that there is a need for “life transition” courses for women who are interested in understanding how to improve their health and well-being.
Processor-level reliability simulator for time-dependent gate dielectric breakdown

Time-dependent gate dielectric breakdown (TDDB) is a leading reliability concern for modern microprocessors. In this paper, a framework is proposed to analyze the impact of TDDB on state-of-art microprocessors and to estimate microprocessor lifetimes due to TDDB. Our methodology finds the detailed electrical stress and temperature of each device within a microprocessor system running a variety of standard benchmarks. Combining the electrical stress profiles, thermal profiles, and device-level models, we perform timing analysis on the critical paths of a microprocessor using our methodology to characterize microprocessor performance degradation due to TDDB and to estimate the lifetime distribution of logic blocks. In addition, we study DC noise margins in conventional 6T SRAM cells as a function of TDDB degradation to estimate memory lifetime distributions. The lifetimes of memory blocks are then combined with the lifetimes of logic blocks to provide an estimate of the system lifetime distribution.
The Prospect of Plasticity: Malleability Views of Group Differences and their Implications for Intellectual Achievement, Mental/Behavioral Health, and Public Policy

This article critically examines the psychological and policy implications of the belief that characteristics of social groups are grounded in biology and thus are unchangeable. We specifically focus on how this immutability mind-set may perpetuate group-based educational achievement gaps and deter treatment seeking for mental/behavioral health conditions. We then consider the prospect of plasticity: the notion that psychological attributes, although rooted in our biological endowment, are inherently malleable. Our discussion reviews the evidence for—and social implications of—this alternative mind-set for intellectual achievement as well as mental/behavioral health. We conclude by describing several concrete policy applications of a plasticity perspective.
The Relationship between Birth Weight (BW), Body Mass Index (BMI) and Insulin Sensitivity (S I ) in Prepubertal Caribbean Hispanic (CH) and Black African-American (BAA) Girls with Premature Adrenarche (PA)

The Relationship between Birth Weight (BW), Body Mass Index (BMI) and Insulin Sensitivity (S I ) in Prepubertal Caribbean Hispanic (CH) and Black African-American (BAA) Girls with Premature Adrenarche (PA)
Intrachain triplet energy transfer in platinum-acetylide copolymers.

A series of platinum−acetylide homo- and copolymers was prepared and characterized by using photophysical methods. The polymers feature repeat units of the type [trans-Pt(PBu3)2(C⋮CArC⋮C)], where Ar = 1,4-phenylene (P) or 2,5-thienylene (T). The properties of homopolymers that contain only the 1,4-phenylene or 2,5-thienylene repeat units were compared with those of random copolymers having the structure −[−(Pt(PBu3)2(C⋮CTC⋮C))x−(Pt(PBu3)2(C⋮CPC⋮C))(1-x)-] where x = 0.05, 0.15, and 0.25. Absorption and photoluminescence spectroscopy demonstrates that the singlet and triplet excitations localized on 1,4-phenylene units are higher in energy relative to those localized on the 2,5-thienylene units. The mechanism and dynamics of intrachain triplet energy transfer from 1,4-phenylene to the 2,5-thienylene repeats were explored in the copolymers. Photoluminescence and nanosecond transient absorption spectroscopy indicate that at room temperature P → T energy transfer is efficient and rapid (k ≫ 108 s-1), even in t...
Slurs, stereotypes, and in-equality: A critical review of “How Epithets and Stereotypes are Racially Unequal”

Are racial slurs always offensive and are racial stereotypes always negative? How, if at all, are racial slurs and stereotypes different and unequal for members of different races? Questions like these and others about slurs and stereotypes have been the focus of much research and hot debate lately, and in a recent article Embrick and Henricks (2013) aimed to address some of the aforementioned questions by investigating the use of racial slurs and stereotypes in the workplace. Embrick and Henricks (2013) drew upon the empirical data they collected at a baked goods company in the southwestern United States to argue that racial slurs and stereotypes function as symbolic resources that exclude minorities but not whites from opportunities or resources and that racial slurs and stereotypes are necessarily considered as negative or derogatory irrespective of their particular context of use (pp. 197–202). They thus proposed an account of slurs and stereotypes that supports the context-insensitive position of Fitten (1993) and Hedger (2013) yet challenges the context-sensitive position of Kennedy (2002) and Croom (2011). In this article I explicate the account of racial slurs and stereotypes provided by Embrick and Henricks (2013), outline 8 of their main claims, and then critically evaluate these claims by drawing upon recent empirical evidence on racial slurs (both in-group and out-group uses) and stereotypes (for both whites and blacks) to point out both strengths and weaknesses of their analysis. Implications of the present analysis for future work on slurs and stereotypes will also be discussed.
A Quantitative Comparison of Delta Wing Vortices in the Near-Wake For Incompressible and Supersonic Free Streams

When requiring quantitative data on delta wing vortices for design purposes, low-speed results have often been extrapolated to configurations intended for supersonic operation. This practice stems from a lack of database in high-speed flows due to measurement difficulties. An attempt is made to examine this practice by comparing data from an incompressible flow experiment designed specifically to correspond to an earlier experiment in supersonic flows. The comparison is made for a 75° sweptback delta wing at angles of attack of 7° and 12°. For the incompressible flow, detailed flow-field properties including vorticity and turbulence characteristics are obtained by hot-wire and pressure probe surveys
Resistance and disease in Brugia malayi infection of ferrets following prior infection, injection of attenuated infective larvae and injections of larval extracts

SUMMARY A partial resistance expressed by a 53% to 78% reduction in lymphatic filariae from a challenge infection was induced in ferrets (Mustela putorius furo) by a prior infection and by injection of radiation attenuated infective larvae (L3) but not by injections of lyophilized microfilariae (mf) or L3. Equivalent acquired resistance was demonstrated with and without overt filarial disease. A prior infection resulted in peripheral lymphoedema in approximately one-third of the amicrofilaraemic resistant ferrets following challenge infection and injection of attenuated larvae resulted in inflammatory responses characteristic of a hyper-responsive syndrome in one-half of the amicrofilaraemic ferrets. Injections of lyophilized mf inhibited microfilaraemia and promoted development of lymphostatic disease. A limited examination of immune responses and histopathology suggested that disease in partially resistant ferrets was associated with high TH2 dependent responses directed, at least in part, to mature filariae and to mf. Mechanisms of resistance were not identified.
An investigation of categorical speech discrimination by rhesus monkeys

The categorical discrimination of synthetic human speech sounds by rhesus macaques was examined using the cardiac component of the orienting response. A within-category change which consisted of stimuli differing acoustically in the onset of F2 and F3 transitions, but which are identified by humans as belonging to thesame phonetic category, were responded to differently from a no-change control condition. Stimuli which differed by the same amount in the onset of F2 and F3 transitions, but which human observers identify as belonging toseparate phonetic categories, were differentiated to an even greater degree than the within-category stimuli. The results provide ambiguous data for an articulatory model of human speech perception and are interpreted instead in terms of a feature-detector model of auditory perception.
Effects of acute administration of caffeine on local cerebral glucose utilization in the rat

The quantitative 2-[14C]deoxyglucose autoradiographic method was used to study the effects of acute intravenous injections (15 min prior to study) of caffeine on brain energy metabolism. With doses of 0.1 mg/kg the effects of caffeine on cerebral glucose utilization were limited to the habenula, spinal trigeminal and paraventricular nuclei. After the 1.0 mg/kg dose significant increases were additionally seen in the caudate, ventral tegmental area and medial septum. After the injection of 10 mg/kg of caffeine, average glucose utilization of the brain as a whole was increased by 15%, and of 71 structures examined 31 structures were statistically significantly affected. Among these were all brainstem monoaminergic cell groupings, components of the extrapyramidal motor system, anterior cingulate, and medial prefrontal cortex. In the hypothalamus glucose utilization increased only in the paraventricular nucleus, arcuate nucleus, and median eminence. This study demonstrates that there is a correlation between the known stimulant effects of caffeine on behavior and widespread increases in glucose utilization throughout the brain.
Turnover and Storage of Newly Synthesized Adenine Nucleotides in Bovine Adrenal Medullary Cell Cultures

The adenine nucleotide stores of cultured adrenal medullary cells were radiolabeled by incubating the cells with 32Pi and [3H]adenosine and the turnover, subcellular distribution, and secretion of the nucleotides were examined. ATP represented 84-88% of the labeled adenine nucleotides, ADP 11-13%, and AMP 1-3%. The turnover of 32P-adenine nucleotides and 3H-nucleotides was biphasic and virtually identical; there was an initial fast phase with a t1/2 of 3.5-4.5 h and a slow phase with a half-life varying from 7 to 17 days, depending upon the particular cell preparation. The t1/2 of the slow phase for labeled adenine nucleotides was the same as that for the turnover of labeled catecholamines. The subcellular distribution of labeled adenine nucleotides provides evidence that there are at least two pools of adenine nucleotides which make up the component with the long half-life. One pool, which contains the bulk of endogenous nucleotides (75% of the total), is present within the chromaffin vesicles; the subcellular localization of the second pool has not been identified. The studies also show that [3H]ATP and [32P]ATP are distributed differently within the cell; 3 days after labeling 75% of the [32P]ATP was present in chromaffin vesicles while only 35% of the [3H]ATP was present in chromaffin vesicles. Evidence for two pools of ATP with long half-lives and for the differential distribution of [32P]ATP and [3H]ATP was also obtained from secretion studies. Stimulation of cell cultures with nicotine or scorpion venom 24 h after labeling with [3H]adenosine and 32Pi released relatively twice as much catecholamine as 32P-labeled compounds and relatively three times as much catecholamine as 3H-labeled compounds.
Visual recognition capacity during outdoor recreation experiences.

The capacity of outdoor recreationists to recognize visual scenes they have experienced during an on-site engagement is reported. Visual recognition capacity is considered important since sightseeing is a major aspect of most wildland recreation engagements, and because "recollection" is a major component of the recreation experience. Visual recognition is also an important aspect of environmental perception and cognition; of how humans see an area and learn to know it. Seven hundred and fifty hikers of a National Park Service trail were surveyed, using a photo questionnaire, for their ability to recognize trail scenes after hiking the trail environment. Results indicate (1) human ability to recognize visual material may be as remarkable for natural environments as researchers have shown for built environments; (2) sightseeing is not a passive activity, hikers were able to recognize certain themes in the environment more effectively than others; (3) interpretive signs placed along the trail as an experime...
Self-enhancement versus self-verification: Does spousal support always help?

The current study replicates and extends previous work on self-enhancement and self-verification processes in marriage. A community sample of married individuals (N = 265) completed a self-esteem scale, perceived spousal support scale, and various measures of marital adjustment. Consistent with self-enhancement theory, higher levels of self-esteem support were related to higher levels of marital quality and stability across all indices for both men and women. Consistent with self-verification theory, greater discrepancies between self-esteem and perceived partner self-esteem support were related to lower levels of marital satisfaction among wives, and lower levels of satisfaction and intimacy among husbands. Consistent with the combined operation of self-enhancement and self-verification, greater partner self-esteem support was associated with increases in marital quality only up to the point that it verified self-esteem. It is concluded that self-enhancement and self-verification strivings may operate independently of each other within the marital context. Both theoretical and clinical implications of these findings are discussed.
Integrin Alpha 6 regulates glioblastoma stem cells

Cancer stem cells (CSCs) are a subpopulation of tumor cells suggested to be critical for tumor maintenance, metastasis, and therapeutic resistance. Prospective identification and targeting of CSCs are therefore priorities for the development of novel therapeutic paradigms. Although CSC enrichment has been achieved with cell surface proteins including CD133 (Prominin-1), the roles of current CSC markers in tumor maintenance remain unclear. We examined the glioblastoma stem cell (GSC) perivascular microenvironment in patient specimens to identify enrichment markers with a functional significance and identified integrin alpha6 as a candidate. Integrin alpha6 is coexpressed with conventional GSC markers and enriches for GSCs. Targeting integrin alpha6 in GSCs inhibits self-renewal, proliferation, and tumor formation capacity. Our results provide evidence that GSCs express high levels of integrin alpha6, which can serve not only as an enrichment marker but also as a promising antiglioblastoma therapy.
Identification of photo-induced paramagnetic centers in As43S57 glass by electron spin resonance☆

Abstract The electron spin resonance spectrum of photo-induced paramagnetic centers in glassy As43S57 has been measured. From an analysis of the As75 hyperfine tensor, we conclude that each of four different defect structures associated with neutral undercoordinated As atoms can account for the observed ESR spectrum. Arguments are presented to show that the diamagnetic structures of these centers are valence alternation defects. Two kinds of these valence alternation pairs require such large energy for creation that they can exist only when the glass becomes heterogeneous as a result of a strain-relief mechanism.
Adenosine deaminase activity in normal tissues and tissues from a child with severe combined immunodeficiency and adenosine deaminase deficiency

Abstract We determined and partially characterized adenosine deaminase activity (ADA) in normal tissues and in tissues from a patient with ADA deficiency and severe combined immunodeficiency. Normal lymphoid tissues (and particularly thymus) contained the highest ADA activity which was present primarily as the less heat-stable, low molecular weight form of the enzyme. These same lymphoid tissues in the patient contained the lowest relative amounts of residual ADA activity when compared with the relative residual activity in liver, lung, and kidney. The residual ADA activity in liver was not found to differ from the normal in distribution between different molecular weight forms (an abnormality previously reported in spleen of another patient). However, an abnormality in distribution between electrophoretic forms of the enzyme was found. The fact that the major clinically deleterious effects of ADA deficiency are observed in the lymphoid system may correlate with the high levels of activity as well as with the predominance of the less heat-stable, free RBC form of the enzyme found in these tissues.
Scattering characteristics in heterogeneously fractured reservoirs from waveform estimation

SUMMARY OVset-dependent characteristics of seismic scattering are useful for characterizing fractured reservoirs. We use two models that have diVerent background medium properties and diVerent azimuthal AVO responses to study elastic wave propagation and scattering in gas-saturated, heterogeneously fractured reservoirs. Heterogeneous fracture density distributions are built through stochastic modelling. Synthetic seismograms are generated by 3-D finite diVerence modelling, and waveforms along crack-normal and strike directions are considered in this paper. The multiple signal classification (MUSIC) frequency estimator is used in waveform estimation to provide frequency-domain attributes related to seismic wave scattering by fracture heterogeneity. Our results indicate that the strength of the scattering field is a function of the background medium. The strength also increases with increasing fracture scatterer density and with decreasing correlation length of spatial variations of fracture density. The scattering field is weak at the top of the fractured reservoir. The first-order results are dominated by velocity anisotropy of the mean fracture density field. However, the base of the fractured reservoir corresponds to a strong scattering field on which fracture heterogeneity has a larger eVect and is characterized by the loss of coherence.
Dimensional analysis and equilibrium radiation

Professor Dhawan and I have been colleagues and friends for a very long time; to be more precise, for more than 35 years, ever since Dr. Dhawan came from Minnesota to Caltech as a graduate student. By now he has caught up with me in everything but age. Similarity and dimensional analysis have played an important role in his research as well as in mine. For some years now I have been playing with the application of dimensional analysis to statistical thermodynamics. This little study of radiation thermodynamics is offered as a tribute to Dr. Dhawan as a small token for a great scientist, engineer, administrator and, most of all, human being.
Syntheses of colchicine and isocolchicine labelled with carbon-11 or carbon-13

The syntheses of isotopically labelled (−)-10-[11C/13C]-colchicine and (−)-9-[11C/13C]- isocolchicine have been achieved from the reaction of (−)desmethylcolchicine with [11C/13C]-iodomethane. The radiolabelled compounds, (−)-10-[11C]-colchicine (11C-n-colchicine) and (−)-9-[11C]-isocolchicine (11C-i-colchicine), were isolated by reversed phase HPLC. The total synthesis time was approximately 60 minutes for both radiolabelled compounds with an average specific activity of 240 mCi/μmol calculated to EOB. Utilizing a similar synthetic strategy, we also report the synthesis of milligram quantities of the carbon-13 enriched compounds and the magnetic resonance signal assignment for (−)-9-[13C] isocolchicine.
Systematic study of the Altissimae and Giganteae species groups of the genus Vernonia (Compositae)

Morphological variation within and between the taxa of the Altissimae (Vernonia altissima, V. ovalifolia, andV. flaccidifolia) and Giganteae (V. gigantea) was investigated. The data for these studies were obtained from population samples, herbarium specimens, and greenhouse-grown transplants. The taxa were hybridized in all possible combinations, and F2 progeny were produced fromV. altissima XV. ovalifolia F2’s. Fertility in the hybrids was estimated by examination of chromosome pairing at meiosis and by pollen stainability. It is concluded thatVernonia altissima should be regarded as a synonym ofV. gigantea and thatV. ovalifolia should be reduced to subspecific rank asV. gigantea ssp.ovalifolia. The evolution of the two subspecies ofV. gigantea is discussed.Vernonia flaccidifolia is maintained at the species level.
Remembering the Body: Eighteenth-Century Elocution and the Oral Tradition

Abstract: This article revisits eighteenth-century elocutionists Thomas Sheridan and John Walker by examining their work in two contexts: 1) classical imitation and oral reading traditions that engaged the body and emotions; and 2) early modern views of the faculties, particularly the faculties of the imagination and taste. These contexts, I argue, are essential to understanding the social and ethical claims the elocutionists made to support the revival of elocution and to understanding how they perceived their own practices.
Endothelial nitric oxide synthase mediates the cerebrovascular effects of erythropoietin in traumatic brain injury.

Background: Erythropoietin (Epo) improves post-traumatic cerebral blood flow (CBF), pressure auto-regulation, and vascular reactivity to L-arginine. This study examines the dependence of these cerebral hemodynamic effects of Epo on nitric oxide (NO) generated by endothelial nitric oxide synthase (eNOS). Methods: Using laser Doppler flow imaging, CBF was monitored in wild-type (WT) and eNOS-deficient mice undergoing controlled cortical impact (CCI) followed by administration of Epo (5000 U/kg) or normal saline. Results: CBF decreased in all groups post-injury with the greatest reductions occurring at the impact site. Epo administration resulted in significantly higher CBF in the peri-contusional sites in the WT mice (70.2 ± 3.35 % in Epo-treated compared to 53 ± 3.3 % of baseline in saline-treated mice (p< .0001), but no effect was seen in the eNOS-deficient mice. No CBF differences were found at the core impact site where CBF dropped to 20-25% of baseline in all groups. Conclusion: These differences between eNOS-deficient and WT mice indicate that the EPO mediated improvement in CBF in TBI is eNOS dependent.
A novel 20-kilodalton protein conserved in Babesia bovis and B. bigemina stimulates memory CD4(+) T lymphocyte responses in B. bovis-immune cattle.

Acquired immunity against the hemoprotozoan parasite Babesia bovis is believed to depend on activation of antigen-specific CD4+ T lymphocytes and IFN-γ production. A strategy was employed to identify potentially protective antigens from B. bovis based on memory CD4+ T lymphocyte recognition of fractionated merozoite proteins. Fractions of merozoites separated by continuous flow electrophoresis (CFE) that contained proteins of approximately 20 kDa were shown previously to stimulate memory CD4+ lymphocyte responses in B. bovis-immune cattle with different MHC class II haplotypes. Expression library screening with rabbit antiserum raised against an immunostimulatory 20-kDa CFE fraction identified a 20-kDa protein (Bbo20) that contains a B lymphocyte epitope conserved in geographically distant B. bovis strains. An homologous 20-kDa protein that has 86.4% identity with Bbo20 and contains the conserved B cell epitope was identified in B. bigemina (Bbg20). Southern blot analysis indicated that both Babesia proteins are encoded by a single gene. Antibody against recombinant Bbo20 protein identified the antigen in CFE fractions shown previously to stimulate memory T lymphocyte responses in immune cattle. To verify Bbo20 as an immunostimulatory T lymphocyte antigen, CD4+ T cell lines were propagated from B. bovis-immune cattle with merozoite antigen and shown to proliferate significantly against recombinant Bbo20 protein. Furthermore, Bbo20-specific CD4+ T cell clones proliferated in response to several B. bovis strains and produced IFN-γ. BLAST analysis revealed significant similarity of the Bbo20 and Bbg20 amino acid sequences with the hsp20/α-crystallin family.
A parallel algorithm for sparse symbolic Cholesky factorization on a multiprocessor

Abstract We develop an algorithm for computing the symbolic Cholesky factorization of a large sparse symmetric positive definite matrix. The algorithm is intended for a message-passing multiprocessor system, such as the hypercube, and is based on the concept of elimination forest. In addition, we provide an algorithm for computing these forests along with a discussion of the algorithm's complexity and a proof of its correctness.
High-resolution, high-flux, user friendly VLS beamline at the ALS for the 50–1300 eV energy region

Abstract We describe a bending magnet beamline designed to operate on a third generation synchrotron light source—the Advanced Light Source (ALS)—in the energy range 50–1300 eV. It was constructed for the characterization of optical elements (mirrors, gratings, multilayers, detectors, etc.) but has capabilities for a wide range of measurements in other fields, in particular materials science and atomic physics. The optical system consists of a monochromator, a reflectometer, a three-mirror order suppressor, and horizontal and vertical focusing mirrors to provide a small spot on the sample. The monochromator is a varied line spacing, plane grating (VLS-PGM) design in which the mechanically ruled grating operates in the converging light from a spherical mirror working at high demagnification. The spherical aberration of this mirror is corrected by the grating line spacing variation, so that the monochromator is essentially aberration-free over its tuning range. Wavelength is scanned by simple rotation of the grating with a fixed exit slit. The small size and stability of the ALS source allows entrance slitless operation, leading to high flux and a spectral resolving power λ/Δλ of around 7000, limited by the ALS vertical source size. The reflectometer has the capability of positioning the sample to 10 μm and setting its angular position to 0.002°. LABVIEW™-based software provides a convenient interface to the user. The reflectometer is separated from the beamline by a differential pump, and can be pumped down to 10−7 torr in 0.5 h. This allows rapid turn-around of materials science samples for measurements which do not require UHV, such as NEXAFS. Auxiliary experimental stations can be mounted behind the reflectometer. Results are shown which demonstrate the performance and operational convenience of the beamline.
Friction microprobe studies of ion implanted polymer surfaces

Abstract Recent studies at Oak Ridge National Laboratory (ORNL) have shown that ion implantation of polymers can significantly improve wear properties, sometimes dramatically. In several cases, the “best-wear resistance” condition for a specific counterface material was associated with the lowest friction coefficient values. To explore the friction behavior of ion implanted polymers further, microfriction studies were conducted on 1 MeV Ar + implanted poly (ether ether ketone) (PEEK) and polystyrene (PS), implanted to fluences of 5, 10 and 50 × 10 18 ions m −2 . The studies were conducted using the ORNL friction microprobe, a specialized micro-contact tribometer. The results were compared with macro-friction values obtained using standard pin-on-disk type tests. The polymers were also characterized for surface mechanical properties using a nanoindentation technique. Results indicated that the most striking aspect of the microfriction tests on the ion implanted polymers was a marked “stick-slip” behavior, which was not observed for the unirradiated polymers. This friction behavior was related to the three-dimensionally cross-linked structure of the ion irradiated polymer material, since, with increasing fluence, the polymer surface becomes harder and less elastic due to a greater extent of cross-linking. The stick-slip behavior was thus caused by adhesion of the two surfaces, and periodic elastic extension and sudden release of the cross-linked structure of the implanted layer. The microfriction results were correlated with nanoindentation hardness measurements, which are an indirect measure of the extent of cross-linking.
Pilot testing of the computerized cognitive test Microcog™ in chemotherapy-treated older cancer patients

Abstract Background: Chemotherapy has a potential for inducing cognitive side effects. However, no study has focused on elderly cancer patients, a group that might be at risk for this complication. Computerized cognitive tests are available and could simplify cooperative group studies on the matter, but have not been applied to older cancer patients. Methods: We tested the performance of Microcog™ (short form) in a sample of 10 consecutive cancer patients, aged 70 and older, having received chemotherapy. Patients were also asked by questionnaire to express their comments on the test. Results: Six patients had never used a computer. All reported at least minor visual impairment. All did complete the test without pause. Nine out of 10 thought that most patients like them would have no problems completing the test. As a group, our patient sample generally performed within normal limits for age and education. There were a wide range of scores for the majority of the subscales, with the greatest variability of scores in Spatial Processing and Information Processing Accuracy and the least variability in reaction time . The results were robust when assessed by level of computer literacy, minor auditory and visual problems, and fluent English as a second language. Conclusions: A computer test such as Microcog™ appears well feasible in older cancer patients. It appears robust to comorbidity. This bodes well for a potential use of such tests in trials conducted in this patient population.
Elucidating and Minimizing the Loss by Recombinant Vaccinia Virus of Human Immunodeficiency Virus Gene Expression Resulting from Spontaneous Mutations and Positive Selection

While characterizing modified vaccinia virus recombinants (rMVAs) containing human immunodeficiency virus env and gag-pol genes, we detected nonexpressing mutants by immunostaining individual plaques. In many cases, the numbers of mutants increased during successive passages, indicating strong selection pressure. This phenomenon provided an opportunity to investigate the formation of spontaneous mutations in vaccinia virus, which encodes its own cytoplasmic replication system, and a challenge to reduce the occurrence of mutations for vaccine production. Analysis of virus from individual plaques indicated that loss of expression was due to frameshift mutations, mostly by addition or deletion of a single nucleotide in runs of four to six Gs or Cs, and large deletions that included MVA DNA flanking the recombinant gene. Interruption of the runs of Gs and Cs by silent codon alterations and moving the recombinant gene to a site between essential, highly conserved MVA genes eliminated or reduced frameshifts and viable deletion mutants, respectively. The rapidity at which nonexpressing mutants accumulated depended on the individual env and gag-pol genes and their suppressive effects on virus replication. Both the extracellular and transmembrane domains contributed to the selection of nonexpressing Env mutants. Stability of an unstable Env was improved by swapping external or transmembrane domains with a more stable Env. Most dramatically, removal of the transmembrane and cytoplasmic domains stabilized even the most highly unstable Env. Understanding the causes of instability and taking preemptive actions will facilitate the development of rMVA and other poxviruses as human and veterinary recombinant vaccines.
An Adaptive Opto-electronic Neural Network for Associative Pattern Retrieval

A novel adaptive trinary neural network model is proposed for associative pattern retrieval from incomplete data. Systematic analysis of the convergence mechanism for the character recognition problem is provided to illustrate the derivation of this novel adaptive thresholding scheme. The adaptive scheme with trinary input representation outperforms other associative retrieval schemes in terms of convergence and storage capacity. The inherent parallelism of this neural network architecture is exploited for a parallel optical implementation. The tremendous speed and free-space interconnection capability of optics results in a very efficient real-time character recognition system. The adaptive threshold scheme developed here may have far reaching implications for other neural networks in enhancing their learning and retrieval, speed, and accuracy.
The future of large format HgCdTe arrays for astronomy

Rockwell has developed the 256 x 256 NICMOS3 FPA for the Hubble Space Telescope under funding from NASA through the University of Arizona. Since 1989, dozens of science grade devices have been delivered to astronomers throughout the world for ground based infrared observations. These devices have excellent sensitivity at 77K with mean dark currents of 0.1 e-/s, noise of 25 e-, and quantum efficiency of 55–70%. Pixel yields as high as 99.9% have been achieved. Our present plans are to develop a 1024 x 1024 FPA with 2.5 micron cutoff and make it available to astronomers. Such large arrays are made possible by the advances in detector material size (3 in. diameter PACE-I wafers), multiplexer advances (ability to verify the design in detail and availability of advanced foundries), and novel hybridization and reliability approaches.
Integrated sensors in biological environments

Abstract This paper reviews the application and operation of integrated sensors and actuators in biological and physiological environments. Integrated transducers are widely employed for invasive and non-invasive patient monitoring, for recording and understanding biological events and systems, for delivery of chemicals and electrical stimuli into the body, and as a means for eventual realization of closed-loop visual, auditory and muscular prostheses. The state-of-the-art in the development of precision microstructures, interface electronics and signal processing, and packaging and encapsulation for integrated transducers operating in biological environments are discussed. The technologies derived from research on biomedical integrated sensors that have been applied to sensors used in other application areas are presented.
Cohomology of Infinitesimal and Discrete Groups

An infinitesimal algebraic group over a field k is a (connected) algebraic group scheme whose coordinate ring is a finite dimension~al k-algebra. If one begins with a reductive algebraic group G defined over Fp, then one has a close relationship between the representation theory of G, that of its infinitesimal subgroups G, (defined as the kernels of the Frobenius endomorphisms ~rr: G-+ G), and that of its finite (Chevalley) subgroups G(Fq) of Fq-rational points (q = pd). A basic theorem of Cline et al. I-9, Theorem 6.6] relates the cohomology of G in a rational representation to that of the finite groups G(Fq). Related work of Cline et al. [6] and of the authors 1-16] relates the cohomology of G to that of its infinitesimal subgroups. A determination of the cohomology of the first infinitesimal subgroup G 1 of G with trivial coefficients has enabled the authors in [14] to make certain explicit cohomology calculations for the finite groups G(Fq) with certain nontrivial coefficients. In this paper, we continue our study of infinitesimal subgroups of simple algebraic groups by proving various qualitative properties of their cohomology and by extending our computational knowledge. In particular, we provide a computation which applies in a range of degrees to Chevalley groups over the prime field. We also investigate the cohomology of infinitesimal subgroups of nilpotent groups, enabling us for example to determine the cohomology of their Lie algebras in certain cases. We apply this Lie algebra cohomology computation to determine the integral cohomology of various torsion free, nilpotent groups modulo "small prime" torsion, thereby extending a theorem of Dwyer [12]. In more detail, the paper begins in Sect. 1 with a spectral sequence converging to the cohomology of the first infinitesimal subgroup G~ which was previously studied in [14]. From this spectral sequence, it easily follows that H*(G1, M) is a Noetherian H*(G1, k)-module for each finite dimensional rational Gl-module M. We then apply the work of Andersen and Jantzen [1] on the Gl-cohomology of induced modules to obtain the analogous result for the second infinitesimal subgroup Gz. Our analysis also permits a determination of the "generic
The association between self-injurious behaviors and autism spectrum disorders

A key area of concern in children with autism spectrum disorders (ASDs) are self-injurious behaviors (SIBs). These are behaviors that an individual engages in that may cause physical harm, such as head banging, or self-biting. SIBs are more common in children with ASD than those who are typically developing or have other neurodevelopmental disabilities. Therefore, it is important that clinicians who work with children with ASD have a solid understanding of SIB. The purpose of this paper is to review the research on the epidemiology of SIB in children with ASD, factors that predict the presence of SIB in this population, and the empirically supported behavioral treatments available.
Long-term keratometric changes after penetrating keratoplasty for keratoconus and Fuchs Endothelial dystrophy.

Purpose To compare long-term keratometric changes after penetrating keratoplasty (PK) for keratoconus and Fuchs endothelial dystrophy. Design Retrospective, comparative case series. Methods We retrospectively analyzed 168 corneas after PK for keratoconus (85 eyes of 63 subjects) and Fuchs dystrophy (83 eyes of 60 subjects). Patients were examined after final suture removal at 12 months after PK to 30 years after surgery. Operations were performed by one surgeon (W.M.B.) using the same suturing technique in all cases. Eyes were excluded from further analysis after regrafting or after relaxing incisions. Mean keratometric corneal power and astigmatism were measured by manual keratometry. Data were assessed by using generalized estimating equation models to determine change over time. Results Mean keratometric corneal power and astigmatism increased through 30 years after PK for keratoconus ( P P P = .55 and P = .55) The change in keratometric corneal power and astigmatism after PK in keratoconus patients only differed from the change in Fuchs dystrophy patients 10 or more years after PK ( P = .002 and P = .003). Conclusions Corneal curvature and regular astigmatism increase progressively after PK for keratoconus, but remain stable after PK for Fuchs dystrophy. Our data suggest that keratometric instability after PK for keratoconus is attributable to delayed, progressive ectasia in the host corneal rim.
A novel technique to determine difference contours between digital and physical objects for projection moiré interferometry

Projection moire interferometry (PMI) is an out-of-plane displacement measurement technique, and consists of capturing reference and deformed images of a grid pattern projected on the test object. By differencing the reference and deformed images of the projected grid pattern, a fringe pattern is generated from which the displacement field can be extracted. Due to the projection-oriented nature of this technique, measuring displacements in applications with non-viewable, hidden, or inaccessible reference surfaces excludes the use of PMI. This paper presents a technique for computing the difference contours between a digital and physical object. A CAD model of the inaccessible surface is converted to a point cloud and a surface interpolation function is implemented to generate a digital displacement field, which can be correlated and differenced from the displacement field of the physical object determined through traditional PMI methods. These techniques are validated by comparing results from an airfoil with other measurement methods.
Role of defensins in the pathogenesis of chronic lung allograft rejection.

Chronic rejection predominantly manifested as bronchiolitis obliterans syndrome (BOS), still remains a major problem affecting long-term outcomes in human lung transplantation (LTx). Donor specific antibodies (DSA) and infiltration of neutrophils in the graft have been associated with the development of BOS. This study determines the role of defensins, produced by neutrophils, and its interaction with α-1-antitrypsin (AAT) towards induction of airway inflammation and fibrosis which are characteristic hallmarks of BOS. Bronchoalveolar lavage (BAL) and serum from LTx recipients, BOS+ (n=28), BOS-(n=26) and normal healthy controls (n=24) were analyzed. Our results show that BOS+ LTx recipients had higher α-defensins (HNP1-3) and β-defensin2 HBD2 concentration in BAL and serum compared to BOS-DSA-recipients and normal controls (p=0.03). BOS+ patients had significantly lower serum AAT along with higher circulating concentration of HNP-AAT complexes in BAL (p=0.05). Stimulation of primary small airway epithelial cells (SAECs) with HNPs induced expression of HBD2, adhesion molecules (ICAM and VCAM), cytokines (IL-6, IL-1β, IL-13, IL-8 and MCP-1) and growth-factor (VEGF and EGF). In contrast, anti-inflammatory cytokine, IL-10 expression decreased 2 fold (p=0.002). HNPs mediated SAEC activation was completely abrogated by AAT. In conclusion, our results demonstrates that neutrophil secretory product, α-defensins, stimulate β-defensin production by SAECs causing upregulation of pro-inflammatory and pro-fibrotic signaling molecules. Hence, chronic stimulation of airway epithelial cells by defensins can lead to inflammation and fibrosis the central events in the development of BOS following LTx.
Surgical Technique and Peripheral Artery Disease

Invasive treatment for patients with peripheral artery disease (PAD) has changed dramatically. Medicare claims data from 1996 to 2006 reveal an almost doubling of lower-extremity vascular procedures: The use of endovascular repair increased >3-fold, bypass surgery decreased 42%, and the amputation rate decreased by 29%.1 For patients admitted to hospital for PAD between 1996 and 2005, the likelihood of undergoing surgery decreased from 34.5% to 26.3%.2 Although the rate of bypass is decreasing, surgery remains an important component in the armamentarium for treating patients with advanced vascular disease. Surgical revascularization is indicated in patients with acceptable surgical risk who require a more durable repair, in those with lesions technically unsuitable for endovascular repair, and in patients who experienced failure of endovascular repair. Despite significant increases in patient morbidity, surgical bypass has become safer over the past 2 decades. Nationally, mortality after surgical bypass decreased from 7% to 4% from the 1980s to mid-1990s. From 1998 to 2003, mortality for open and combined procedures stabilized at 3% to 4%.3 Data from the National Inpatient Survey comparing outcomes in 1998 and 2007 show significant reductions in complication rates across all categories except infection.4 Several factors may account for improved outcomes: a shift to endovascular therapy or “limited” open surgery to achieve revascularization in high-risk patients; better patient selection; more effective medication regimens consisting of a statin, an antiplatelet agent, and β-blocker; and improved intraoperative care and postoperative management. This review examines the risk of adverse events after vascular surgery, identifies strategies for determining and decreasing cardiac risk, and describes contemporary surgical approaches to treating patients with PAD. Patients with symptomatic PAD frequently have concomitant cerebrovascular or coronary artery disease (CAD) that places them at high risk for adverse cardiovascular outcomes after surgery. Direct reconstruction for aortoiliofemoral disease is …
A convenient single step preparation of dopamine-4-O-sulfate

Synthese par traitement de la dopamine avec H 2 SO 4 dans la glace. Determination de la constante de dissociation par spectrophotometrie
Comparison of ab initio and multipole determinations of the electrostatic interaction of acetamide dimers

Abstract In this study, we used a constrained least-squares method to determine parameters for use in an atomic multipole description of the electrostatic energy. To test the accuracy of the parameters, we compared acetamide dimer binding energies determined from the multipole scheme with those from a Morokuma analysis. Interestingly, it was found that a model employing only atomic point charges was able to accurately reproduce the ab initio electrostatic energies at the van der Waals separation of the dimer. The least-squares charges were closer to Mulliken charges than to other definitions which have been suggested. At closer distances, penetration of the charge distributions invalidates the multipole expansion.