cssi/SciSciGPT-SciSciNet huggingface dataset:
Low temperature thermal cycle survivability and reliability study for brushless motor drive electronics

This paper presents a survivability and reliability investigation for integrated actuator and brushless motor drive electronics packaging and components under an extreme low temperature and high thermal cycle environment. A universal brushless motor drive electronics assembly has been designed, built, and thermal cycle tested for use in Mars, Moon, and asteroid type cold environments without the need for any active thermal control. The assembly uses electronic part types and chip-on-board electronic packaging technology that allow operation at temperatures down to -180/spl deg/C. The thermal cycle capability of the assembly has been demonstrated to be in excess of 2010 cycles from -120/spl deg/C to 85/spl deg/C, over a 210/spl deg/C total temperature swing. Future space missions will require electronic and actuator systems on a planet, asteroid or Moon surface to function beyond the established reliability limits of currently used components and materials systems. In support of this target application, the Jet Propulsion Laboratory (JPL) has performed a series of experiments to test the reliability of actuators, sensors, electronic components, and electronic packaging designs to provide input to the detailed flight design of a universal brushless motor drive electronics and integrated actuator assembly. These experiments started with the use of a chip-on-board electronic packaging strategy due to its inherent advantage of improved high functionality with minimal circuit board area compared with standard packaged electronic components. Initial electronic packaging experiments were comprised of various sized chip devices with gold wire bonds. The second phase of electronic packaging experiments conducted at JPL consisted of power devices with large diameter wire bonds as well as various surface mount resistor devices. Full factorial experiments were designed to find the most reliable combinations of substrate type, component attach method and encapsulation. The surviving material combinations after a minimum of 1500 thermal cycles were utilized to form the basis of the packaging and electronic component detailed design approach used in the universal brushless motor drive electronics design. Electrical failures were defined as open circuits. A failure analysis procedure was applied by defining the failure mechanism and applying a risk mitigation. After 1500 cycles, the packaged assembles were cycled to exceed 2010 cycles and additional material considerations were made. In addition, selected components were functionally tested over the temperature range of +100/spl deg/C to -180/spl deg/C and cold soaked at -150/spl deg/C for 1000 hours for reliability. A design for reliability method was also developed at the component and circuit level for electronics operating at extreme low temperatures.
Role of association on protein adsorption isotherms : β-lactoglobulin a adsorbed on a weakly hydrophobic surface

Abstract This paper explores the role of association on the adsorption isotherms of β-lactoglobulin A on a weakly hydrophobic stationary phase at 4°C and mobile phases of 0.85 M and 1 M ammonium sulfate, pH 4.5. The isotherms, obtained by frontal analysis, show an S-shape and the corresponding Scatchard plots indicate positive cooperativity. The slopes and intercepts of the Scatchard plots at low solute concentration are analyzed in terms of two species —a protomer and a higher order stronger adsorbing species. An explicit equation of the isotherm is developed based on this model, and this expression is shown to reproduce the isotherm shape using the appropriate derived parameters. It is further shown from this equation that a Langmuir-shaped adsorption isotherm can be obtained if the higher order associate or aggregate binds weaker to the support than the protomer. These results indicate that protein—protein interactions and the formation of associates can play a significant role on the shape of the isotherm and ultimately on the behavior of the species in preparative scale chromatography.
Cap Bocage: when a mountain fell into the sea

This documentary by Jim Marbrook, a filmmaker and television studies lecturer from Auckland, opens with the view from a helicopter flying along a coastline in New Caledonia, a French possession in ...
Use of afferent triggered averaging to study the central connections of muscle spindle afferents.

Publisher Summary This chapter discusses central connections of muscle spindle afferents, using afferent triggered averaging. The synaptic connections of single identified muscle spindle Ia and group II afferents are studied in low spinal cats by the spike-triggered averaging (STA) of synaptic noise in motoneurons of various types. By using STA at higher sensitivity than before, it has been possible to reveal monosynaptic excitatory postsynaptic potentials (EPSPs) below the previously reported lower limits—down indeed to 2.2 μV. Mean monosynaptic EPSP amplitude for spindle group II projections is less than 50% of that for Ia projections. Both groups contained EPSPs ≤ l0μV, but only 11.5% of the spindle group II EPSPs are ≥50 μV in contrast to 41% of the Ia EPSPs. In further contrast, the Ia afferents appear to make more profuse monosynaptic connections with homonymous and heteronymous motoneurons than spindle group II afferents. High sensitivity STA recording further permits the measurement of a presynaptic spike, which shows that, while synaptic delay is of similar duration for Ia and spindle group II projections, the central conduction time is significantly longer for the spindle group II impulses. The use of STA in preparations with a high level of spontaneous interneuronal discharge permits the demonstration of disynaptic, and sometimes even later excitatory and inhibitory effects.
Management of Aneurysm Perforation during Guglielmi Electrodetachable Coil Placement

We read with interest the case report presented by Willinsky and terBrugge ([1][1]) regarding a technique of using a second microcatheter to treat perforation of a ruptured paraophthalmic aneurysm during initial catheterization. Having had experience with a similar situation during endovascular
Structural analysis of the KRIT1 ankyrin repeat and FERM domains reveals a conformationally stable ARD-FERM interface.

Cerebral cavernous malformations (CCM) are vascular dysplasias that usually occur in the brain and are associated with mutations in the KRIT1/CCM1, CCM2/MGC4607/OSM/Malcavernin, and PDCD10/CCM3/TFAR15 genes. Here we report the 2.9 A crystal structure of the ankyrin repeat domain (ARD) and FERM domain of the protein product of KRIT1 (KRIT1; Krev interaction trapped 1). The crystal structure reveals that the KRIT1 ARD contains 4 ankyrin repeats. There is an unusual conformation in the ANK4 repeat that is stabilized by Trp-404, and the structure reveals a solvent exposed ankyrin groove. Domain orientations of the three copies within the asymmetric unit suggest a stable interaction between KRIT1 ARD and FERM domains, indicating a globular ARD-FERM module. This resembles the additional F0 domain found N-terminal to the FERM domain of talin. Structural analysis of KRIT1 ARD-FERM highlights surface regions of high evolutionary conservation, and suggests potential sites that could mediate interaction with binding partners. The structure therefore provides a better understanding of KRIT1 at the molecular level.
Loss to Clinic and Five-Year Mortality among HIV-Infected Antiretroviral Therapy Initiators

Missing outcome data due to loss to follow-up occurs frequently in clinical cohort studies of HIV-infected patients. Censoring patients when they become lost can produce inaccurate results if the risk of the outcome among the censored patients differs from the risk of the outcome among patients remaining under observation. We examine whether patients who are considered lost to follow up are at increased risk of mortality compared to those who remain under observation. Patients from the US Centers for AIDS Research Network of Integrated Clinical Systems (CNICS) who newly initiated combination antiretroviral therapy between January 1, 1998 and December 31, 2009 and survived for at least one year were included in the study. Mortality information was available for all participants regardless of continued observation in the CNICS. We compare mortality between patients retained in the cohort and those lost-to-clinic, as commonly defined by a 12-month gap in care. Patients who were considered lost-to-clinic had modestly elevated mortality compared to patients who remained under observation after 5 years (risk ratio (RR): 1.2; 95% CI: 0.9, 1.5). Results were similar after redefining loss-to-clinic as 6 months (RR: 1.0; 95% CI: 0.8, 1.3) or 18 months (RR: 1.2; 95% CI: 0.8, 1.6) without a documented clinic visit. The small increase in mortality associated with becoming lost to clinic suggests that these patients were not lost to care, rather they likely transitioned to care at a facility outside the study. The modestly higher mortality among patients who were lost-to-clinic implies that when we necessarily censor these patients in studies of time-varying exposures, we are likely to incur at most a modest selection bias.
The Economic Turn in Comparative Politics

This article emphasizes comparative politics research that combines the tools and theories of economics, primarily microeconomics, with the tools and theories of political science. It traces and as...
Determination and classification of added caramel color in adulterated acerola juice formulations

Four batches of acerola juice concentrate were suspected of being adulterated with caramel color from a specific caramel color raw material. Analyses of both the caramel color raw material and the finished acerola juice products were conducted. The detection of the caramel marker compounds 5-HMF and 4-MeI in the raw material was consistent with its classification as a class IV caramel color. A distinctive four-peak sequence in the HPLC−UV profile of the raw material was used to match the caramel color to its commercial source. The same four-peak sequence was used to detect and quantify added caramel color in the finished acerola juice products. This is the first report of an adulterated acerola juice product and the first report in which added caramel color has been matched to its commercial source. Keywords: Caramel color; HPLC profiling; acerola; juice adulteration
The formation of cadmium fluoride by metal-fluorine reaction

The formation of CdF2 by cadmium-fluorine reaction is described in detail, as a prototype for metal-gas reactions that proceed by the diffusion of the anionic species through the reaction product layer, and where yields of product are sought, rather than a protective coating over the metal. With metal powder, 100% conversion is readily achieved in less than an hour and at relatively low ambient temperature (≤300°C). Higher temperatures and longer exposure time to fluorine are required to convert solid metal samples of reasonable cross section to fluoride with practical yield (≥90%); transparent, coarse-grained solid of high purity CdF2 is the resulting product in this case. Optical spectra of such samples are presented and compared to previously reported ones.
The clinical and imaging spectrum of findings in patients with congenital lobar emphysema

Congenital lobar emphysema (CLE) is an important cause of infantile respiratory distress that may require surgical intervention. We retrospectively reviewed the clinical and imaging findings in eight infants with CLE. In our series, CLE was more common in females, predominantly involved the right lung, often presented with an opaque lobe from retained fetal lung fluid, and frequently involved the lower lobes, multiple segments or lobes, and both lungs. Most patients with CLE were diagnosed and managed on the basis of clinical and plain radiographic findings alone. Computed tomography, and occasionally ventilation/perfusion scintigraphy, were helpful in confirming the diagnosis and in guiding management decisions in several cases; bronchoscopy showed that stenosis of the right mainstem bronchus was the cause of CLE in one case. Three patients experienced progressive worsening of respiratory distress and required surgical resection of the affected lobe for cure; the remaining five patients were managed medically with eventual remission of symptoms.
Measurements of the relative permittivity of liquid water at frequencies in the range of 0.1 to 10 kHz and at temperatures between 273.1 and 373.2 K at ambient pressure

The static relative permittivity (dielectric constant) of water has been determined from capacitance measurements at frequencies between 0.1 and 10 kHz, in the temperature range from 273.2 to 373.2 K at ambient pressure. The capacitor used for these measurements was formed from sapphire-insulated concentric cylinders. The specific conductance of the water used was maintained within 20% of the lowest value ever observed, which is better than in all previous experiments in this range. The new data shed some light on a discrepancy between sets of literature data in liquid water between the triple and boiling points.
Multiple risk factor reduction in the prevention of cardiovascular disease.

Abstract Two hundred and forty members of Varian Corporation were screened for risk of heart disease. After random assignment, 12 high risk subjects were treated with a behavior modification treatment; 10 with individual counseling; and 14 with single-time physician consultation. Treatment for the first two groups lasted for a period of 11 weeks. Treatment objectives were to achieve behavior change affecting weight, smoking, diet, and physical activity and change in cholesterol and triglyceride levels as deemed necessary from each subject's individual risk score. It was predicted that behavior modification and individual counseling treatments would achieve significantly greater initial change than the physician consultation and that the behavior modification treatment would maintain changes longer than either the individual counseling treatment or physician consultation. Posttest data confirm the first prediction; three-month follow-up data support the second.
John P. Dougherty: Some recollections

What follows are some personal recollections of John that I thought might be of interest to some readers of this special issue of the Journal of Plasma Physics.
The Rôle of Vitamin G in Reproduction in Poultry

Abstract THE vitamin G complex as found in dried liver, autoclaved yeast, and dried whey was reported by Bethke, Record, and Kennard (1933) to exert a beneficial effect upon hatchability. Shell-free, hard boiled eggs produced by the hens on the different diets when fed to chicks on a diet deficient in the vitamin G complex were found to vary in their content of this vitamin. Halpin, Holmes, and Hart (1933) reported that by supplementing a basal diet deficient in vitamin G with skimmilk, chopped alfalfa hay, or autoclaved yeast the hatchability of the eggs of hens fed this diet was increased. Heiman and Norris (1933) and later Heiman (1935) presented evidence showing that vitamin G was required for hatchability and that the riboflavin content of eggs was in direct proportion to the amount of vitamin G supplied the hens. Dried skimmilk and dried whey were the sources of vitamin G used . . .
Physical characteristics of corn kernels as influenced by nitrogen fertilization

Physical characteristics of corn (Zea mays L.) kernels influence end‐use. Agronomic practices including nitrogen (N) fertilization may influence kernel hardness. The objective of this study was to ...
Time-resolved plasma properties for double pulsed laser-induced breakdown spectroscopy of silicon☆

A systematic measurement of plasma properties (temperature, electron number density, pressure) was performed during LIBS of silicon with two nanosecond pulsed lasers operating at 1064 nm. The spectral characteristics of the plasmas were measured to determine the plasma properties as delay time between the laser pulses was changed from 0 to 10 ms. The plasma properties and crater dimensions increased abruptly from 100 to 200 ns. The crater depth increased from 2 to 10 μm (volume increased about 5 times) per pair of double pulses. Enhanced mass removal was indicative of a phase explosion mechanism. Spatial images of plasma emission were measured to study the dynamics of plasma expansion.
THE MEASUREMENT OF TRUST AND ITS RELATIONSHIP TO SELF‐DISCLOSURE

This study examined the relationship of trust to self-disclosure. A measure of individualized trust was developed and used in conjunction with a multidimensional measure of disclosure to reassess the relationship between the two. A modest, linear relationship between individualized trust and various dimensions of self-disclosure was discovered. Moreover, a higher level of trust (as opposed to lesser trust as well as distrust) was found to be associated with more consciously intended disclosure and a greater amount of disclosure.
Avoidance of predator chemical cues by bats: an experimental assessment

[Predation places selection pressure on the behaviour of organisms, but the effect of predation risk on bat behaviour has gone largely untested. Using a Y-maze, we tested the hypothesis that female big brown bats ( Eptesicus fuscus ) avoid olfactory cues from known predators — raccoons ( Procyon lotor ) and black rat snakes ( Elaphe obsoleta ). These chemical cues are most likely encountered by bats during the assessment of potential roost sites, so avoidance of predator cues could affect roost selection. We found that big brown bats do not avoid cues from raccoon urine and there was a non-significant trend for bats to choose the arm with black rat snake cues. In a second experiment, bats were exposed to olfactory and potentially auditory cues of live black rat snakes. Bats tended to avoid the arm with live snakes, although results were non-significant. This suggests olfactory cues may not be representative of live snakes, or that auditory cues may be more important than olfactory cues for predator recognition. During late spring, female bats often avoid torpor for thermoregulatory or reproductive reasons. Therefore, bats may be alert to the approach of predators and be less responsive to chemical cues compared to other times of the year., Predation places selection pressure on the behaviour of organisms, but the effect of predation risk on bat behaviour has gone largely untested. Using a Y-maze, we tested the hypothesis that female big brown bats ( Eptesicus fuscus ) avoid olfactory cues from known predators — raccoons ( Procyon lotor ) and black rat snakes ( Elaphe obsoleta ). These chemical cues are most likely encountered by bats during the assessment of potential roost sites, so avoidance of predator cues could affect roost selection. We found that big brown bats do not avoid cues from raccoon urine and there was a non-significant trend for bats to choose the arm with black rat snake cues. In a second experiment, bats were exposed to olfactory and potentially auditory cues of live black rat snakes. Bats tended to avoid the arm with live snakes, although results were non-significant. This suggests olfactory cues may not be representative of live snakes, or that auditory cues may be more important than olfactory cues for predator recognition. During late spring, female bats often avoid torpor for thermoregulatory or reproductive reasons. Therefore, bats may be alert to the approach of predators and be less responsive to chemical cues compared to other times of the year.]
Calculations of microporosity and mesoporosity by the chi theory method

Abstract The chi theory of physical adsorption was used to analyze a variety of porous materials. A minimum search routine was utilized to determine the parameters: pore radius, average adsorption energy of the first adsorbate molecule per pore, the distribution of this energy from pore to pore and the overall surface area. Criteria for pre-filling of pores beyond simple adsorption is developed and used to analyze mesoporosity. Theoretically, all porous materials will exhibit the switch over to pre-filling of the pores, but this behavior depends upon the pore radius and the adsorptive pressure, and some data did not cover a large enough range of pressures to demonstrate this. Reasonable values for the physical quantities are obtained when the data scatter is reasonably low and the range of the measurement includes a reasonable number of data points below and above the change from simple adsorption to the pre-filled condition.
A GLOBAL TEST OF FACTORIZATION FOR NUCLEON–NUCLEON, γp AND γγ SCATTERING

The purpose of this paper is to show that the cross-section factorization relation σnn(s)/σγp(s) = σγp(s)/σγγ(s) is satisfied experimentally in the energy domain , where the σ's are total cross-sections and nn denotes the even portion of the pp and total cross-section. A convenient phenomenological parametrization for a global simultaneous fit to the pp, , γp and γγ total cross-section data together with the ρ-value data for pp and is provided by using real analytic amplitudes. Within experimental errors, we show that factorization is satisfied when we unfold the published γγ data which had averaged the cross-sections obtained by using the two different PHOJET and PYTHIA Monte Carlo results. Our analysis clearly favors the PHOJET results and suggests that the additive quark model, together with vector meson dominance, allows one to compute σγp(s) and σγγ(s) from σnn(s) with essentially no free parameters. The universal ρ-value predicted by our fit, i.e. ρnn = ργp = ργγ, is compared to the ρ-value obtained by a QCD-inspired analysis of and pp data, including the p-air cross-sections from cosmic rays. The ρ-values obtained from the two techniques are essentially indistinguishable in the energy region , giving us increased confidence in our parametrization of the cross-sections needed for the factorization relation.
The “Don't Catch the Flu Bear Blues” educational campaign to increase hand hygiene awareness during the flu vaccine shortage in an orthopedic specialty hospital

ISSUE: On October 5, 2004, there was news from the Centers for Disease Control and Prevention (CDC) that due to problems in manufacturing of the influenza vaccine for the 2004-2005 season, the expected supply was reduced. Because of the situation, persons who were not included in one of the priority groups were asked to forego or defer vaccination. In an effort to prevent the transmission and acquisition of the influenza virus, an educational campaign was designed to increase awareness to the importance of hand hygiene and respiratory etiquette. PROJECT: The theme of the educational program was “Don't Catch the Flu Bear Blues” and involved the distribution of wicker baskets filled with a teddy bear with a pediatric mask on its face, bottles of alcohol-based hand rub, respiratory etiquette flyers, an educational poster, and candy kisses. The baskets were distributed to each of the infection control liaisons from the following departments: inpatient nursing units, radiology, acute care unit, intensive care unit, patient access, laboratory, rehab unit, prescreening unit, operating room, post anesthesia care unit, and induction room area. Baskets were re-filled with alcohol hand rub and candy over a 4-week period. The project cost was approximately $700, which included the baskets, bears, candy, and hand rub. Four cases of hand rub were donated by the pharmacy department to contribute to reducing influenza transmission from the reduction in vaccine supplies. RESULTS: Fifteen baskets were distributed the week before the holidays in the spirit of a gift basket to the liaisons. They were instructed to keep the basket and teddy bear after the campaign was completed. Staff was delighted to receive the individual bottles of hand rub, as were the patients who received bottles in patient access. LESSONS LEARNED: Unique, creative hand hygiene campaigns heighten awareness of the importance of handwashing and the use of alcohol-based hand rubs in patient care areas. It was a great way to market the infection control program and boost staff morale during an unusual flu vaccine season. A turnkey approach to setting up the educational campaign, including sources for vendors and a detailed budget, will be presented.
High-tech will improve radiotherapy of NSCLC: a hypothesis waiting to be validated.

n the management of patients with non–small-cell lung ancer (NSCLC), surgery is the modality of choice. Only hen disease is locally advanced, or when the tumor is nresectable, is radiotherapy the primary option. This is artly due to the poor treatment outcome of conventional adiotherapy for this disease site. For early-stage disease reated with conventional radiotherapy, the 2-year local ontrol of medically inoperable tumors is approximately 0%–50%, and only 15%–20% for locally advanced disease 1, 2). In contrast, local control after surgery can be as high s 80% (2). The addition of chemotherapy has not substanially altered the disparity between these results (3). Selecion bias may contribute part of the difference, because atients referred for radiotherapy generally have lower perormance status, poorer pulmonary function, and are more ikely to have comorbid illnesses. The poor results of radiotherapy for NSCLC may be due lso to deficiencies in conventional radiation treatment techiques. It is now recognized that, in many cases, computed omography (CT) images alone do not reveal the entire xtent of NSCLC tumors. Positron emission tomography ith F-labeled fluorodeoxyglucose (FDG-PET) often reeals regions of high metabolism, indicative of cancers not etected by CT (4–15). Second, the substantial respiratory otion of the lung may move part of the target outside the adiation field, causing underdosage of part of the tumor 16–21). Third, to cover the target adequately in the presnce of respiratory motion, a large margin is usually added o the radiation field, increasing the probability of morbidity nd limiting the dose that can be safely administered. Reent technical advances can address each of these difficulies. The inadequacy of CT-based tumor volume delineation ay be partially overcome by incorporating FDG-PET data
The C1q family of proteins: insights into the emerging non-traditional functions.

Research conducted over the past 20 years have helped us unravel not only the hidden structural and functional subtleties of human C1q, but also has catapulted the molecule from a mere recognition unit of the classical pathway to a well-recognized molecular sensor of damage modified self or non-self antigens. Thus, C1q is involved in a rapidly expanding list of pathological disorders—including autoimmunity, trophoblast migration, preeclampsia and cancer. The results of two recent reports are provided to underscore the critical role C1q plays in health and disease. First is the observation by Singh and colleagues showing that pregnant C1q-/- mice recapitulate the key features of human preeclampsia that correlate with increased fetal death. Treatment of the C1q-/- mice with pravastatin restored trophoblast invasiveness, placental blood flow, and angiogenic balance and, thus, prevented the onset of preeclampsia. Second is the report by Hong et al., which showed that C1q can induce apoptosis of prostate cancer cells by activating the tumor suppressor molecule WW-domain containing oxydoreductase (WWOX or WOX1) and destabilizing cell adhesion. Downregulation of C1q on the other hand enhanced prostate hyperplasia and cancer formation due to failure of WOX1 activation. Recent evidence also shows that C1q belongs to a family of structurally and functionally related TNFα-like family of proteins that may have arisen from a common ancestral gene. Therefore C1q not only shares the diverse functions with the TNF family of proteins, but also explains why C1q has retained some of its ancestral “cytokine-like” activities. This review is intended to highlight some of the structural and functional aspects of C1q by underscoring the growing list of its non-traditional functions.
Severe 2010 Amazon drought in historical context

[1] In 2005 a severe once-in-a-century drought struck the Amazon rain forest. Just 5 years later, an even more severe and widespread drought struck the region. How do these extreme events fit into the context of historical droughts? Marengo et al. looked at historical rainfall and river data sets to find out. They found that the 2010 drought was unique. It started in early summer during an El Nino event and intensified due to warming of the tropical North Atlantic, which was warmer than in any previous year in the records since 1903, including 2005. Their analysis indicates that warming in the tropical North Atlantic affects the hydrology of the Amazon region by promoting a longer dry season, which can be aggravated if there was low rainfall in the previous wet season. They observe that there has been an increase in dry and very dry events in the whole Amazon region since the middle 1970s as well as an increase in the length of the dry season. (Geophysical Research Letters, doi:10.1029/2011GL047436, 2011)
Psychologists in Academic Health Settings: Key Contributors to Dynamic Interplay Among Research, Clinical Practice, and Policy Domains

Psychologists in academic health systems are in a unique position to impact the dynamic interplay among research, clinical practice, and policy domains. In addition to their specialty expertise in psychopathology, particular types of physical illness and disease, and health promotion, psychologists have substantial knowledge of human behavior, refined scientific skills, knowledge and experience in the effective delivery of clinical services, strengths in written expression, and a collaborative orientation. This combination of strengths makes psychologists extremely well-suited for (a) interdisciplinary efforts to develop and implement evidence-based assessment and intervention strategies with biological, psychological, behavioral, and social components, and (b) leadership and advocacy efforts that impact the quality and availability of health care services.
Microbial Biogeography of Arctic Streams: Exploring Influences of Lithology and Habitat

Terminal restriction fragment length polymorphism and 16S rRNA gene sequencing were used to explore the community composition of bacterial communities in biofilms on sediments (epipssamon) and rocks (epilithon) in stream reaches that drain watersheds with contrasting lithologies in the Noatak National Preserve, Alaska. Bacterial community composition varied primarily by stream habitat and secondarily by lithology. Positive correlations were detected between bacterial community structure and nutrients, base cations, and dissolved organic carbon. Our results showed significant differences at the stream habitat, between epipssamon and epilithon bacterial communities, which we expected. Our results also showed significant differences at the landscape scale that could be related to different lithologies and associated stream biogeochemistry. These results provide insight into the bacterial community composition of little known and pristine arctic stream ecosystems and illustrate how differences in the lithology, soils, and vegetation community of the terrestrial environment interact to influence stream bacterial taxonomic richness and composition.
Coating sections for electron microscopic autoradiography: a stripping technique using liquid emulsion.

SUMMARY A coating technique for electron microscope autoradiography is described which combines the advantage of forming an emulsion film by a dipping method with the ease of coating sections already on grids. Sections are coated so that a formvar support film separates the section and the emulsion crystals. This intermediate layer of formvar ensures a random distribution of the emulsion crystals. Using light gold sections, Ilford L-4 emulsion and Microdol-X development, the resolution of this technique, as determined by the half distance method, was 150 nm. The additional layer of formvar slightly reduced the image quality with biological samples in the electron microscope. This technique has a minimal loss of resolution and image quality for moderate resolution electron microscope autoradiography.
An apospory‐specific genomic region is conserved between Buffelgrass (Cenchrus ciliaris L.) and Pennisetum squamulatum Fresen

Summary Twelve molecular markers linked to pseudogamous apospory, a form of gametophytic apomixis, were previously isolated from Pennisetum squamulatum Fresen. No recombination between these markers was found in a segregating population of 397 individuals (Ozias-Akins et al., 1998, Proc. Natl Acad. Sci. USA, 95, 5127‐5132). The objective of the present study was to test if these markers were also linked to the aposporous mode of reproduction in two small segregating populations of Cenchrus ciliaris (= Pennisetum ciliare (L.)Link), another apomictic grass species. Among 12 markers (sequence characterized amplified regions, SCARs), six were scored as dominant markers between aposporous and sexual C. ciliaris genotypes (presence/ absence, respectively). Five were always linked to apospory and one showed a low level of recombination in 84 progenies. Restriction fragment length polymorphisms (RFLPs) were observed between sexual and apomictic phenotypes for three of the six remaining SCARs from P. squamulatum when used as probes. No recombination was observed in the F 1 progenies. Preliminary data from megabase DNA analysis and sequencing in both species indicate that an aposporyspecific genomic region (ASGR) is highly conserved between the two species. Although C. ciliaris has a smaller genome size to P. squamulatum, a higher copy number for markers linked to apospory found in the former may impair the progress of positional cloning of gene(s) for apomixis in this species.
Breadth of the α-Relaxation Function in 1,4-Polybutadiene

Mechanical and dielectric spectroscopy studies of local segmental motion (α-relaxation) in polybutadienes are reviewed and new results presented. Previous mechanical spectra for 1,4-polybutadiene r...
THE PERITONEAL EXUDATE LYMPHOCYTE I. DIFFERENCES IN ANTIGEN RESPONSIVENESS BETWEEN PERITONEAL EXUDATE AND LYMPH NODE LYMPHOCYTES FROM IMMUNIZED GUINEA PIGS

Peritoneal exudate lymphocytes from guinea pigs immunized with horse radish peroxidase, dinitrophenyl guinea pig albumin, or ferritin in complete Freund's adjuvant have been shown to be significantly more reactive than other lymphocytes in two in vitro assays of cellular immune function: production of macrophage migration inhibitory factor and antigen-induced lymphocyte proliferation. The enhanced reactivity of peritoneal exudate lymphocytes cannot be accounted for by artifacts introduced by column purification or by the presence of nonlymphoid accessory cells. These observations suggest that the peritoneal exudate lymphocyte pool is a highly enriched source of cellular immune effector cells with specificity directed towards those antigenic determinants to which an animal has been recently exposed.
Residue Number System In Content-Addressable Memory Processors

The advantage of using the residue number system in content-addressable memories is explained. The implementations of addition and multiplication with these processors are presented. The conversion of residue numbers to their equivalent binary numbers is described. The direct implementation of an 8-bit adder with residue-based content-addressable memories is investigated.
SU‐FF‐T‐97: Application of a Rotatable Isocentric Phantom for Determining Geometric Errors in Gantry Rotation of a Complete LINAC System Including EPID and OBI

Purpose: With the onset of on‐board‐imaging (OBI) and 2D‐2D matching programs to determine table shifts in IGRT, QA tests are needed to assess the accuracy of these shifts. Hence, the purpose of this study was to investigate geometric inaccuracies in that could occur within a LINAC with EPID and OBI due to gravity effects when the gantry is rotated. Method and Materials: A rotatable isocentric phantom (Modus Medical Devices) was aligned to the lasers in our CT simulator. CT scans with 1mm slice thicknesses were transferred to the Eclipse TPS. DRR's were generated and exported into our IMPAC R&V system. The phantom was then aligned to the lasers in the Linac room. A Varian iX LINAC with EPID and OBI was used to obtained orthogonal pairs of images with the gantry set to 0°, 90°, 180°, and 270°. For each image the phantom was rotated such that its top surface was parallel to the imaging detector. The Varian 2D‐2D image matching program on the OBI computer was used to determine the geometric inaccuracies. Results: The initial set up of the phantom immediately revealed a misalignment of 2.5mm in the external lasers in the CT simulator. In addition, the CT scanner table sagged as much as 3.9 cm as it entered and passed the bore with an 68kg on the table. Imaging on the Linac with the MV or kV source at 0° (top) showed images that were perfectly aligned. However, when the kV source and detector was used at 270° or 90°, the images were up to 2mm off due to gravity effects. Conclusions: A technique was developed to determine the geometric inaccuracies found in a LINAC with EPID and OBI. Equipment sag showed that table shifts of less than 2mm may not be real or needed.
Growth and properties of Ba0.9Sr0.1TiO3 single crystal fibers

Abstract Ba 0.9 Sr 0.1 TiO 3 single crystal fibers were successfully grown using the laser heated pedestal growth (LHPG) technique. Tetragonal perovskite phase was found with cell parameters a =3.978 A and c =4.020 A. Temperature dependences of the dielectric constant and thermal expansion properties were analyzed and three sharp anomalies related to the rhombohedral–orthorhombic, orthorhombic–tetragonal and tetragonal–cubic structural transformations were observed.
The Natural Widths of the K -Series of W(74)

By means of a two-crystal x-ray spectrometer of high resolving power at short wave-length, the full widths at half maximum of the $K$-series of W(74) have been measured. The observed widths ${W}_{O}$ in the (1,+1) position of the crystals have been corrected to true widths ${W}_{T}$ by use of the formula ${W}_{T}={W}_{O}\ensuremath{-}{W}_{R}$ where ${W}_{R}$ is the width of the rocking curve of the crystals in the (1,-1) position. It is shown that, in the short wave-length region under consideration the (1,-1) rocking curves obey the Hoyt equation. By using Weisskopf's equation for the shape of a spectral line, the above correction formula results. The following (corrected) full widths at half maximum (in volts) are obtained: $K{\ensuremath{\alpha}}_{2}$, 43.3; ${\ensuremath{\alpha}}_{1}$, 43.0; ${\ensuremath{\beta}}_{3}$, 50.0; ${\ensuremath{\beta}}_{1}$, 48.6; ${\ensuremath{\gamma}}_{2}$, 37.0; ${\ensuremath{\gamma}}_{1}$, 37.0; ${\ensuremath{\delta}}_{2}$, 34.0; ${\ensuremath{\delta}}_{1}$, 34.
Family Distress and Involvement in Relatives of Obsessive-Compulsive Disorder Patients

Obsessive compulsive disorder (OCD) affects the lives of patients as well as their relatives. Calvocoressi et al. (1995) suggested that accommodation (e.g., participating in the patient's rituals) by relatives of patients with OCD was related to global family dysfunction and distress. These investigators did not, however, examine the relationship between family accommodation and severity of the patients' OCD symptoms. In the present study we examined the relationship between families' reactions to the patient's illness (e.g., assistance with rituals, modification of family routine, rejection of the patient, etc.) and the patient's Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) score and Hamilton Depression scale ratings. We also examined the effects of family accommodation and rejection on treatment outcome. Results revealed that family distress, accommodation, and rejection were related to depression and anxiety in the family members, but not to severity of the patients' OCD. At posttreatment, family accommodation and modification of routine was related to the severity of patients' OCD. These results remained significant when the effect of pretreatment OCD severity was partialled out.
Protein and metabolite composition of xylem sap from field-grown soybeans (Glycine max)

The xylem, in addition to transporting water, nutrients and metabolites, is also involved in long-distance signaling in response to pathogens, symbionts and environmental stresses. Xylem sap has been shown to contain a number of proteins including metabolic enzymes, stress-related proteins, signal transduction proteins and putative transcription factors. Previous studies on xylem sap have mostly utilized plants grown in controlled environmental chambers. However, plants in the field are subjected to high light and to environmental stress that is not normally found in growth chambers. In this study, we have examined the protein and metabolite composition of xylem sap from field-grown cultivated soybean plants. One-dimensional gel electrophoresis of xylem sap from determinate, indeterminate, nodulating and non-nodulating soybean cultivars revealed similar protein profiles consisting of about 8–10 prominent polypeptides. Two-dimensional gel electrophoresis of soybean xylem sap resulted in the visualization of about 60 distinct protein spots. A total of 38 protein spots were identified using MALDI-TOF MS and LC–MS/MS. The most abundant proteins present in the xylem sap were identified as 31 and 28 kDa vegetative storage proteins. In addition, several proteins that are conserved among different plant species were also identified. Diurnal changes in the metabolite profile of xylem sap collected during a 24-h cycle revealed that asparagine and aspartate were the two predominant amino acids irrespective of the time collected. Pinitol (d-3-O-methyl-chiro-inositol) was the most abundant carbohydrate present. The possible roles of xylem sap proteins and metabolites as nutrient reserves for sink tissue and as an indicator of biotic stress are also discussed.
Teratogenic activity of 2-amino-1,3,4-thiadiazole hydrochloride in Wistar rats and the protection afforded by nicotinamide.

Pregnant Wistar rats were each injected once ip with various doses of 2-amino-l,3,4-thiadiazole hydrochloride (ATDA) at days 1–16 of gestation (sperm day = day 0). The optimal teratogenic dose was determined to be 100 mg/kg and this dose was employed throughout the experiment. At autopsy at day 20 resorptions and malformations were found in all litters from treated females. Two periods of increased embryonic susceptibility to the lethal effects of ATDA were observed. The first at day 5 (100% resorbed) and the second at days 9 and 10 (71.5 and 92.5% resorbed). Periods of increased sensitivity to the teratogenic action of ATDA were at days 9 through 13, when the incidence of abnormal fetuses produced exceeded 90%. The major malformations were anophthalmia, microphthalmia, hydrocephalus, short tail, taillessness, ectrodactyly, syndactyly, and cleft palate. Other malformations occurred occasionally. The malformations were related to the developmental stage at the time of treatment. Supplemental treatment with nicotinamide at days 5, 11, 12, and 13 markedly diminished the teratogenic and lethal effects of ATDA, and at day 11 the administration of nicotinamide completely abolished its teratogenic activity. ATDA probably acts by interfering with NAD-dependent enzyme reactions.
Oxyradical scavenging effects of dehydroascorbate

Dehydroascorbate (DHA) has been shown to possess vitamin C like activities as well as to protect the lens against oxidative stress and cataract formation. The results presented here suggest that some of the beneficial effects of DHA can be attributed to its property of undergoing peroxidative decarboxylation and of \(O_2^{\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\cdot}$}}{ - } } \) scavenging. Incubation of 1-14C-DHA with peroxide at physiological pH has been found to liberate 14CO2 in quantitative yields, with recovery of 79–94%. The recovery increases with the increase in the amount of DHA used. Its \(O_2^{\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\cdot}$}}{ - } } \) scavenging activity was apparent by inhibition of \(O_2^{\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\cdot}$}}{ - } } \) dependent reduction of ferricytochrome c and nitroblue tetrazolium. The authenticity of the latter mechanism was proved by inhibition of the \(O_2^{ \cdot - } \) dependent reactions also by superoxide dismutase.
Complementary effects of network range and tie strength in enhancing transnational venture performance

We examine the complementary effects of network range and tie strength on the performance of ventures in the context of the transnational entrepreneur (TE). Network range facilitates access to a broad set of knowledge and resources; however these resources may be activated only in the presence of strong ties. Alternatively, a network heavy in strong ties provides reliable connections, but a lack of range can lead to network closure. Using a sample of 452 TE ventures, we find that tie strength enhances venture performance, but network range does not have a significant effect. Furthermore, taken together, tie strength and network range significantly enhance TE venture performance. Supermodularity and linear restriction tests indicate asymmetric complementarity between network range and tie strength. Tie strength is a critical input and network range plays a supporting role in a TE's venture performance. Copyright © 2011 Strategic Management Society.
Random Cantor set models for the elastic-perfectly plastic contact of rough surfaces

The objective of this study was to formulate discrete and continuous spatial models to describe the elastic-perfectly plastic deformation of two rough surfaces in contact. The two surfaces in contact are assumed to exhibit fractal behavior and are modeled as an effective fractal surface compressed into a smooth rigid substrate. The rough self-affine fractal structure of the effective surface is approximated by a random Cantor set representation embedded in two dimensions. Both of the proposed models admit analytical solutions whether the plastic deformation is volume conserving or not. Presented results illustrate the effects that volume conservation and initial surface structure have on the elastic-perfectly plastic deformation process. The results from the continuous model are compared with the results obtained from the discrete model, and existing experimental load displacement data for the deformation of a bead-blasted steel surface.
Rapid acceleration of atherosclerosis in hypertensive rats on high fat diet

Abstract Rats with unilateral renal hypertension were placed on a diet containing 40% fat in the form of egg yolk. In striking contrast to normotensive control rats, these animals rapidly developed a severe grade of atherosclerosis. Gross atherosclerosis of the mesenteric arteries was sometimes visible as early as 2 weeks after ingestion of fat was started. Coronary atherosclerosis was usually present within 1 or 2 months and was characterized by well developed atheromatous plaques, reactive cellular proliferation, and superimposed thrombosis. The rapid acceleration of atherosclerosis was attributed to the vascular damage caused by high blood pressure mainly prior to initiating the high fat diet. This damage apparently resulted in a greater propensity on the part of smooth muscle cells to accumulate lipid particles and in enhanced reactive hyperplasia of these cells on exposure to excess lipids. Another likely effect of the high blood pressure was to increase the permeability of the arterial intima to the passage of lipids.
Securing multi-core multi-threaded packet processors

Modern routers use high-performance multi-core multi-threaded packet processing systems to implement protocol operations and to forward traffic. As the number of processor cores/threads increases, it becomes increasingly difficult to track their correct operation at runtime. In this paper, we discuss how to extent our existing monitoring scheme to support highly parallel environments.