cssi/SciSciGPT-SciSciNet huggingface dataset:
Cryogenic detectors for infrared astronomy: the Single Aperture Far-InfraRed (SAFIR) Observatory

Abstract The development of a large, far-infrared telescope in space has taken on a new urgency with breakthroughs in detector technology and recognition of the fundamental importance of the far-infrared spectral region to questions ranging from cosmology to our own Solar system. The Single Aperture Far-InfraRed (SAFIR) Observatory is 10 m-class far-infrared observatory that would begin development later in this decade to meet these needs. SAFIR's science goals are driven by the fact that youngest stages of almost all phenomena in the universe are shrouded in absorption by and emission from cool dust that emits strongly in the far-infrared, 20 μm–1 mm. Its operating temperature (4 K) and instrument complement would be optimized to reach the natural sky confusion limit in the far-infrared with diffraction-limited performance down to at least the atmospheric cutoff at 40 μm. This would provide a point source sensitivity improvement of several orders of magnitude over that of SIRTF. In order to achieve this, large arrays of detectors with NEPs ranging from a few to a hundred zeptowatts/sqrt(Hz) are needed. Very low temperature superconducting transition edge sensors and far-infrared “photon counting” detectors are critical technologies requiring development for the SAFIR mission.
Equity, equality, and need: A study of the patterns and outcomes associated with their use in intimate relationships

This study examined the extent to which specific justice principles (equity, equality, and need) are associated with different orientations within complex relationships. This contrasts with previous research that has focused on the extent to which justice principle use varies across relationships representing distinctly different goals. Forty-eight men and 60 women were randomly assigned to conditions of equity, equality, or need. Each was asked to describe a recent incident from their own relationship illustrating the principle to which they were assigned. Incidents were coded into one of three domains representing the multiple orientations of intimate relationships. Subjects in the need condition were more likely to describe incidents related to issues of nurturance or personal development, whereas subjects in equity and equality were more likely to describe incidents related to the allocation of responsibilities. Subjects in the equality condition rated their principles as a more desirable basis for decision making in intimate relationships than subjects in either equity or need. Regardless of the relationship domain, subjects in the equality as compared to the equity condition also reported more positive feelings about the decision and themselves as well as more positive and less negative feelings toward their partner.
Psychological reactivity to discrepant events: Support for the curvilinear hypothesis

Abstract 80 male and 60 female infants were observed under 5 a priori judged levels of discrepancy to assess whether sustained attention was linearly or curvilinearly related to degree of discrepancy from an experimental standard. Following habituation, 7 1 2 -month-old infants were exposed to either the repetition of the standard, a minimal, first- or second-level moderate discrepancy, or a novel stimulus having no relation to the standard. The related stimuli, varying in elongation, were sphere, pear, club, and cylinder-shaped objects; the novel stimulus was a different colored, tooth-like object. 80 infants observed the sphere as the standard and the cylinder as the second-level moderate discrepancy; 60 infants were exposed to the reverse order with the cylinder as the standard. The use of different stimuli at each discrepancy level controlled for specific stimulus effects. Habituation and recovery of responding were observed in an operant paradigm. Lever pressing, fixation, and vocalization increased most to the second-level moderate stimuli and decreased most to the familiar and novel objects; fretting was highest to the redundant stimuli and lowest to the moderate objects. There were no stimulus main effects or interactions. The results support the hypothesis of a curvilinear relation between stimulus discrepancy and sustained attention, excitement, and preference.
Liver transplantation complicated by misplaced TIPS in the portal vein.

OBJECTIVE: The purpose of this study was to determine the incidence and complications related to transjugular intrahepatic portosystemic shunt (TIPS) stents found in the portal vein at the time of an orthotopic liver transplantation. BACKGROUND: Transjugular intrahepatic portosystemic shunts are frequently used in patients with end-stage liver disease as a bridge to liver transplantation. The incidence of finding the metal stent outside of the liver parenchyma at the time of transplantation is reported as high as 30%. Most cases that have been detailed involve stents misplaced in the vena cava with various outcomes. Almost no data are available regarding stents misplaced into the portal vein. METHODS AND RESULTS: We report our experience with four patients with whom a TIPS stent was found misplaced in the portal vein at the time of liver transplantation, including one patient with a stent extending into the superior mesenteric vein. This patient required extensive venous reconstruction using a retropancreatic "pant" donor-iliac vein graft. The three other patients were transplanted without the need for extensive venous reconstruction. There was no significant difference in operative times for this group of patients, but there was a significant increase in the requirement for blood transfusion. In a follow-up period ranging from 6 months to 2 years, all patients remained alive and had normal portal venous flow and functioning allografts. Most misplaced stents were placed in patients with small cirrhotic livers and by radiologists with minimal experience with the procedure. CONCLUSIONS: Misplaced TIPS in the portal vein before liver transplantation is a more frequent complication than previously reported; however, it does not represent major technical difficulty if a clamp can be placed proximally on the portal vein. In the case of a stent extending below the spleno-mesenteric confluence, interposition grafts such as a donor-iliac vein graft are necessary for venous reconstruction. The experience of the radiologist is critical to prevent this complication.
Genetic control of an esterase of digestive tract tissues inRattus norvegicus

BeiRattus norvegicus wird eine neue Mutation beschrieben, welche die elektrophoretische Wanderungsgeschwindigkeit eines Intestinalenzymes beeinflusst.
The case for voluntary smallpox vaccination.

The former Soviet Union developed variola virus, which causes smallpox, for use as a biologic weapon, and supplies may have fallen into other hands. As Lev Sandakhchiyev, the director of Russia's Vektor Institute, has warned, “All you need is a sick fanatic to get to a populated place.”1 U.S. experts agree.2,3 The benefits of preemptive, voluntary vaccination are great. One immediate outcome is deterrence. Vaccination before exposure dramatically reduces the value of smallpox as a weapon; in the case of an attack, the number of unimmunized persons will be greatly reduced, and the outbreak will be much easier to . . .
Rapid repletion of brain serotonin in malnourished corn-fed rats following L-tryptophan injection.

Abstract The concentration of tryptophan in serum, and the levels of tryptophan, serotonin (5-HT), and 5-hydroxyindole-acetic acid (5-HIAA) in brain are substantially reduced in rats that consume for 6 weeks a diet in which corn is the only source of protein. Single injections of L-tryptophan (25, 50, or 100 mg/kg) cause dose-related increases in brain tryptophan, 5-HT, and 5-HIAA in corn-fed animals. At each dose, brain tryptophan content rises to a proportionately greater extent in corn-fed rats than in well-nourished controls, even though serum tryptophan concentrations attain higher levels in controls. This difference may reflect the greatly reduced serum concentrations in corn-fed rats of other large neutral amino acids that compete with tryptophan for uptake into the brain (tyrosine, phenylalanine, leucine, isoleucine, and valine). However, the substantial decrease in serum albumin levels also diminishes the binding of tryptophan to serum albumin; thus it is not yet possible to state which of these changes is responsible for the much greater increments in brain tryptophan observed in corn-fed rats after tryptophan injection. The fact that tryptophan administration rapidly restores brain 5-hydroxyindole levels in corn-fed animals suggests that the reductions in 5-HT and 5-HIAA levels associated with this type of malnutrition may be largely caused by inadequate availability of substrate.
Acute to chronic postoperative pain in children: does it exist?

The transition from acute to chronic pain after surgery is a well-studied clinical syndrome that was first described approximately 10 years ago. Since then, a substantial body of literature has evolved exploring this phenomenon in significant detail [1–7]. Known as chronic postoperative surgical pain (CPSP), this clinical entity is highly prevalent, reportedly affecting anywhere from 5 to 50% of adults recovering from surgery. According to the International Association for the Study of Pain, CPSP is a pain syndrome of at least 2 months’ duration, occurs postoperatively, and does not result from other causes such as chronic infection or pre-existing disease. Several predictive patient factors for developing CPSP in adults have been recognized, including the severity of acute postoperative pain, female gender, young age, obesity, preoperative anxiety, pain catastrophizing and a history of pre-existing pain. Acute postoperative pain has emerged as one of the strongest predictors of CPSP [8]. Furthermore, a number of surgical procedures associated with an increased risk of CPSP have been identified such as inguinal herniorrhaphy, thoracotomy, breast surgery and limb amputation. Unfortunately, treatment of CPSP can be a challenging task for the healthcare provider and a difficult burden for the patient to bear. Not only may the patient suffer from significant negative functional and social impact, but there are substantially increased healthcare and economic costs incurred as well. Despite the breadth of evidence examining CPSP in adults, this is a relatively unstudied topic in the pediatric population. Little is known about CPSP in children: whether it even exists, the number of children affected, possible predisposing risk factors and the long-term impact of the disease. Because over 5 million children undergo surgery in the USA each year, the risk of developing CPSP in children is a very real and significant threat. It is reported that the majority of children suffer from clinically significant acute postoperative pain and that this pain is overwhelmingly undertreated, particularly in the home setting [9–15]. A review of the literature found two retrospective questionnaire studies examining the occurrence of CPSP in children [16,17]. These two studies enrolled adult patients who had surgery as children
Feeding behavior and kinematics of the lesser electric ray, Narcine brasiliensis (Elasmobranchii: Batoidea)

Abstract Jaw protrusion is a major functional motif in fish feeding and can occur during mouth opening or closing. This temporal variation impacts the role that jaw protrusion plays in prey apprehension and processing. The lesser electric ray Narcine brasiliensis is a benthic elasmobranch (Batoidea: Torpediniformes) with an extreme and unique method of prey capture. The feeding kinematics of this species were investigated using high-speed videography and pressure transduction. The ray captures its food by protruding its jaws up to 100% of head length (∼20% of disc width) beneath the substrate and generating negative oral pressures (⩽31 kPa) to suck worms into its mouth. Food is further winnowed from ingested sediment by repeated, often asymmetrical protrusions of the jaws (>70° deviation from the midline) while sand is expelled from the spiracles, gills and mouth. The pronounced ram contribution of capture (jaw protrusion) brings the mouth close enough to the food to allow suction feeding. Due to the anatomical coupling of the jaws, upper jaw protrusion occurs in the expansive phase (unlike most elasmobranchs and similar to bony fishes), and also exhibits a biphasic (slow-open, fast-open) movement similar to tetrapod feeding. The morphological restrictions that permit this unique protrusion mechanism, including coupled jaws and a narrow gape, may increase suction performance, but also likely strongly constrain dietary breadth.
The Relationship Between Performance on the Gordon Diagnostic System and Other Measures of Attention

Abstract Tests purporting to measure attention were administered to college students to examine their relationship to three relatively new tests of attention from the Gordon Diagnostic System (GDS). All subjects received the Standard Delay, Vigilance, and Distractibility Tests of the GDS. In addition, 69 of 136 subjects received the Digit Span, Arithmetic, and Digit Symbol subtests of the Wechsler Adult Intelligence Scale-Revised (WAIS-R). and Kagan's Matching Familiar Figures Test. After the GDS, the other 67 subjects received the Visual Span subtest of the Wechsler Memory Scale-Revised (WMS-R), and the Stroop. Replication (across two studies) and gender influences were not evident on GDS performance. Performance data on this test for these 136 college students, collapsed across replication and gender, are presented. Although within-test correlations were strong, correlations between tests were weak. A ceiling effect on the Vigilance task may have effected its correlations with other tests. Results sugge...
Some experimental observations of upstream disturbances in a two-fluid system

This is a brief report on some experimental measurements of flow of two fluids over an obstacle in a channel. A comparison is made between theoretical predictions of upstream disturbances and measurements of the height and speed of the upstream jump and the depth of the lower fluid over the obstacle crest. The results indicate substantial quantitative agreement between theory and observations when the lower fluid has a depth less than that of the upper fluid. When the lower fluid is deeper than the upper, the predicted upstream disturbance does not occur. DOI: 10.1111/j.2153-3490.1974.tb01608.x
The irrelevance of the Consequence Argument

It is worth noting that as van Inwagen originally formulates the doctrine of deter minism, L together with a proposition expressing the total state of the universe at a time later than now necessitate a proposition expressing the total state of the universe now (1983: 65; Campbell 2007: 106). So a version of the Consequence Argument could be constructed using a proposition expressing some distant future total state occurring after the demise of humans about which no one has any choice. Adam's act A, and all other human acts, could presumably be shown to be unfree by means of such an argument. The trick would be to find a future total state that is causally isolated from human acts.
Role of capsule endoscopy as a screening tool for colorectal cancer

SUMMARY Colon capsule endoscopy is currently under evaluation to become a noninvasive colorectal cancer screening test. The sensitivity and specificity of colon capsule endoscopy for colorectal polyps and cancer are improving with ongoing technical refinements to the capsule and recording device, with sensitivity as high as 84% for polyps greater than 1 mm in size. Specificity for smaller polyps, however, remains suboptimal. Colon capsule endoscopy requires extensive bowel preparation to ensure adequate colon cleansing and complete colonic evaluation. The complication rate for colon capsule endoscopy is unclear, but may be lower than that for small bowel capsule endoscopy. The role of colon capsule endoscopy in colorectal cancer screening has not been fully defined, as technical, logistical and implementation issues remain.
Osteoinductive Calcium Phosphate clay nanoparticle bone cements (CPCs) with enhanced mechanical properties

Calcium Phosphate Cements (CPCs) with osteoconductive properties are limited in their applications because of their poor mechanical properties. This study investigated the additive effect of Dexamethasone-doped Halloysite Nanotubes (HNTs on the mechanical properties of CPCs. HNTs are nanosized tubes with alumino-silicate composition. Physico-chemical properties, cytocompatability and cellular functionality of the nanocomposites were assayed. Results suggest that these nanoenhanced composites have a huge potential to broaden the applications of CPCs.
Calibration of hemispherical-head flow angularity probes

The hemisphere-cylinder flow angularity probes were calibrated over a Mach number range of 0.5 to 2.0 at pitch and yaw angles of -5 to +5 deg. Each probe had five pressure orifices in the hemispherical head - one on the axis and four located 45 deg from the axis and equally spaced circumferentially. The probes were identical within fabrication tolerances. Details of probe design, test procedures and data analysis are described and selected test results are presented.
Studies on wheat plants using carbon-14 compounds. 13. Incorporation of alpha-amino adipic acid-6-C14 in wheat plants.

α-Amino adipic acid-6-C14 was injected into the stems of wheat plants and the distribution of carbon-14 in the mature plants was studied. About 80% of carbon-14 injected was recovered in the plants, the kernels alone accounting for 56%.Glutamic acid, labelled predominantly in carbon-5, was the most radioactive compound isolated from wheat kernels, a result in accord with the concept that acetate-1-C14 was a product of α-amino adipic acid-6-C14 metabolism in the wheat plant.The specific activity of the lysine of the protein was low and hence the data provide no evidence that α-amino adipic acid is a precursor of lysine in wheat.
A comparison of the binding properties of fish flesh

Summary Binding properties of loaves prepared from the flesh of ten fish species were evaluated on the basis of visual scores for binding and instrumental measurements of tensile strength. The volume of liquor released on cooking and its content of solids and proteins weremeasured. The only parameters that corresponded with the binding properties were the moisture and fat content of the raw materials. Fish flesh with high fat content (and low moisture content) did not bind well. Bluefish exhibited a big variability with regard to its binding properties, and this corresponded with its variability in fat and moisture content.
A Discontinuous Galerkin Chimera scheme

Abstract The Chimera overset method is a powerful technique for modeling fluid flow associated with complex engineering problems using structured meshes. The use of structured meshes has enabled engineers to employ a number of high-order schemes, such as the WENO and compact differencing schemes. However, the large stencil associated with these schemes can significantly complicate the inter-grid communication scheme and hole cutting procedures. This paper demonstrates a methodology for using the Discontinuous Galerkin (DG) scheme with Chimera overset meshes. The small stencil of the DG scheme makes it particularly suitable for Chimera meshes as it simplifies the inter-grid communication scheme as well as hole cutting procedures. The DG-Chimera scheme does not require a donor interpolation method with a large stencil because the DG scheme represents the solution as cell local polynomials. The DG-Chimera method also does not require the use of fringe points to maintain the interior stencil across inter-grid boundaries. Thus, inter-grid communication can be established as long as the receiving boundary is enclosed by or abuts the donor mesh. This makes the inter-grid communication procedure applicable to both Chimera and zonal meshes. Details of the DG-Chimera scheme are presented, and the method is demonstrated on a set of two-dimensional inviscid flow problems.
Synthesis of novel rigid-rod and tripodal azulene chromophores

Abstract Two novel azulene chromophores 1 and 2 were synthesized to study dynamics of ultrafast electron injection at the interface of TiO 2 semiconductor nanoparticles. Fluorescence quenching was observed upon binding.
Efficient collection and manipulation of laser diode output using refractive micro-optics

The collection efficiency and collimation ability of high numerical aperture circular and cylindrical GaP lenses were evaluated using single index-guided and gain-guided laser diode emitters. Comparisons were made between 200 micrometers focal length cylindrical lenses (NA equals 0.75) fabricated by an accurate repetitive step-wise etching method and 70 micrometers focal length cylindrical lenses (NA > 1) fabricated by a simple resist reflow technique. Lens arrays (200 - 300 micrometers fl, 0.5 - 0.75 NA) fabricated by the repetitive resist-etch method were used to collimate the output of a diode bar consisting of 100 index-guided elements. Refocusing of the collimated light with a macro-optic (for pumping a Nd:YVO 4 laser) produced a spot that was on average 2 - 3 times larger than the diffraction limit and contained up to 88% of the total bar output. The deviation from the theoretical limit was examined in terms of lens fabrication accuracy and alignment tolerances between the diode and lens arrays, which were shown to be on the order of 1 - 2 micrometers .
Capacity decisions for high-tech products with obsolescence

Abstract Modern high-tech products experience rapid obsolescence. Capacity investments must be recouped during the brief product lifecycle, during which prices fall continuously. We employ a multiplicative demand model that incorporates price declines due to both market heterogeneity and product obsolescence, and study a monopolistic firm’s capacity decision. We investigate profit concavity, and characterize the structure of the optimal capacity solution. Moreover, for products with negligible variable costs, we identify two distinct strategies for capacity choice demarcated by an obsolescence rate threshold that relates both to market factors and capacity costs. Finally, we empirically test the demand model by analyzing shipping and pricing data from the PC microprocessor market.
Sexual ideology and experience in a Papua New Guinea society.

Abstract Recent anthropological interest in sexuality has been closely related to symbolic constructions of gender in different societies. Most studies explore the cultural constitution of sexual meanings without addressing how sex is experienced by actors. Material from the Bumbita Arapesh of the East Sepik Province of Papua New Guinea reveals that the local cultural ideology of male sexual domination does not adequately describe actual sexual experiences of Bumbita men and women. Cultural ideology states that men control sexual encounters as a part of their masculine essence, yet in actual marriages women often take the initiative in limiting sexual practice following postpartum prohibitions. Contrary to cultural expectations, men exhibit anxiety concerning sexual relations in a marriage. The public assertion of sexual dominance and suppression of sexual intimacy compensate for a sense of vulnerability accompanying sexual experience. An analytical distinction between “cultural ideology” and “individual experience” helps clarify the climate of sexual relationships in a cultural context.
Optimization Methods For 2-D Prestack Migration Velocity Estimation

Migration velocity analysis is carried out either manually or interactively by migrating seismic data with different trial velocity models and examining the images. We cast this problem into an optimization problem in which a suitably defined objective function is minimized. Crucial to this method is the choice of an objective function since in this problem the target model or image is unknown and computationally intensive approaches to generating synthetic seismograms must be avoided. We, therefore, use a functional of seismic traces, the migrated data themselves, to define an objective function which is generally expected to be well behaved. This is due to the fact that migration is an inherently smoothing process: it collapses diffractions, focuses reflected energy, and suppresses random noise. We essentially use the lateral consistency of reflections after migration as a measure of model misfit. We the apply three optimization approaches to search for the global minima of the objective function: (1) a linearized inversion (LI) or gradient-descent approach, (2) a genetic algorithm (GA), and (3) a recently developed simulated annealing (SA) method called very fast SA. Even for an objective function defined by using the migrated data, we find that a LI method is very sensitive to the choice of initial model indicating that the objective function is multimodal. Both SA and GA were successful in obtaining good images. These methods are computationally intensive, but our choice of spline parameterization reduces the number of model parameters and also use of a fast travel time code for Kirchhoff migration makes the algorithm computationally tractable for real earth problems.
Dissipation of energy and vertical exchange in stratified basins caused by the shear instability in the field of quasiinertial internal waves

We determine the dependences of the rate of dissipation of turbulent energy and the coefficient of vertical turbulent diffusion caused by the shear instability and breaking in the field of inertial gravity internal waves in the ocean on the local buoyancy frequency. Within the framework of a unified approach, we explain the difference between these dependences observed for the areas of the main pycnocline and the upper stratified layer and mentioned in the literature. The indicated difference is explained by the fact that, unlike the region of the main pycnocline, the characteristic vertical scale of the instability of waves in the upper stratified layer depends on stratification. The analysis is performed on the basis of the model of climatic spectrum of internal waves in the ocean proposed by the authors somewhat earlier.
A High-Pressure Spectral Hole Burning Study of Correlation between Energy Disorder and Excitonic Couplings in the LH 2 Complex from Rhodopseudomonas Acidophila

Low-temperature (5 K) nonphotochemical hole burning and absorption spectroscopies were used to study the effects of high pressure (up to 1015 MPa) on excitonic coupling energies and energy disorder in the light-harvesting complex 2 (LH 2) from Rhodopseudomonas Acidophila (strain 10050). The pressure dependences of the widths and positions of the B850 and B870 (lowest exciton level of the B850 ring) bands were determined. The results show, for the first time, that these parameters are linearly correlated (common scaling law), consistent with recent theoretical predictions (Jang; et al. J. Phys. Chem. B 2001, 105, 6655). Excitonic calculations for the B850 ring of bacteriochlorophyll a molecules were performed in the nearest dimer−dimer coupling approximation (Wu; et al. J. Phys. Chem. B 1997, 101, 7654) with E1+ diagonal energy disorder. Such a symmetry is known to dictate the response of the B870 level (absorption bandwidth, displacement (ΔE) from the B850 band maximum) to either diagonal or off-diagonal ...
Age, race, weight, and gender impact normative values of bone mineral density.

Abstract Background Osteoporosis and fractures represent a major public health issue. Accurate normative reference bone mineral density (BMD) values are vital for diagnosing osteoporosis. The generalizability of the T-score method across gender, race, and age in clinic decision-making has been debated. Our aim was to identify the best statistical model to derive normative BMD values in both men and women in the multiethnic United States population. Methods The Third National Health and Nutrition Examination Survey was used as a data source. Gender- and race/ethnicity-stratified data analyses and modeling were conducted on 9779 persons (ages 20 to 65 years) who reported no conditions or medications likely to affect bone metabolism. Sampling and design effects were addressed using STATA 10. Model comparisons were conducted by partial F tests and residual plots. Results Polynomial regression provided a statistically significant better fit than linear regression in predicting normative BMD in both men and women. Age-centered polynomial models provided the best model for predicting normative BMD values. Conclusion The gender- and race-specific lower limit of normal values obtained created a new classification method of low BMD, which might mitigate some of the T-score limitations in men and minority populations.
The utility of the modified wais in a clinical setting

Utilized time-saving WAIS scoring procedures in two ex post facto investigations following approaches outlined by Vincent (1979) and Himelstein (1983). These procedures direct an examiner to use an S's results on the Information subtest as a criterion for determining the point of initial questioning on other scales. Study 1 followed exactly the procedure presented by Himelstein (1983), with an obtained correlation between modified WAIS and WAIS Verbal IQ of .993. In spite of the high correlation, however, significant distortion in results occurred for some Ss, Study 2 integrated and modified slightly the methodologies of Vincent (1979) and Himelstein (1983). Obtained correlations between modified WAIS and WAIS Verbal, Performance, and Full Scale IQs (N = 40) were each .998. The percentage of IQs that differed by more than 2 points between Modified WAIS and WAIS for Verbal, Performance, and Full Scale scores was 0%, 5%, and 2.5%, respectively. In addition, the procedure maintained the integrity of subscale configurations.
Slice-based architecture for biometrics: Prototype illustration on privacy preserving voice verification

This research investigates slice-based architecture for biometrics. A service slice is an aggregation of resources for a specific biometric objective; e.g., speaker verification. Slice-based architecture is attractive as a framework for modeling service-oriented biometric applications. In order for it to be usable, slice-based architecture must adequately address privacy, security, and standard based interoperability. We propose to incorporate secure computation mechanism and BioAPI standard into slice-based architecture. We discuss why secure computation is information-theoretic secure, and how it can be used to realize a private computation for the exchange of biometric data between two parties in slice-based architecture. For proof-of-concept, open source software is developed for realizing a privacy preserving voice verification prototype based on slice-based architecture, and will be released for experimentation by the public. The result of our initial experimentation is reported.
Identification of a New Class of 5′-Adenylylsulfate (APS) Reductases from Sulfate-Assimilating Bacteria

A gene was cloned from Burkholderia cepacia DBO1 that is homologous with Escherichia coli cysH encoding 3*-phosphoadenylylsulfate (PAPS) reductase. The B. cepacia gene is the most recent addition to a growing list of cysH homologs from a diverse group of sulfate-assimilating bacteria whose products show greater homology to plant 5*-adenylylsulfate (APS) reductase than they do to E. coli CysH. The evidence reported here shows that the cysH from one of the species, Pseudomonas aeruginosa, encodes APS reductase. It is able to complement an E. coli cysH mutant and a cysC mutant, indicating that the enzyme is able to bypass PAPS, synthesized by the cysC product. Insertional knockout mutation of P. aeruginosa cysH produced cysteine auxotrophy, indicating its role in sulfate assimilation. Purified P. aeruginosa CysH expressed as a His-tagged recombinant protein is able to reduce APS, but not PAPS. The enzyme has a specific activity of 5.8 mmol z min 21 z mg of protein 21 at pH 8.5 and 30°C with thioredoxin supplied as an electron donor. APS reductase activity was detected in several bacterial species from which the novel type of cysH has been cloned, indicating that this enzyme may be widespread. Although an APS reductase from dissimilatory sulfate-reducing bacteria is known, it shows no structural or sequence homology with the assimilatory-type APS reductase reported here. The results suggest that the dissimilatory and assimilatory APS reductases evolved convergently.
Electrophoretic studies of several dehydrogenases in relation to the cold tolerance of alfalfa.

Abstract Two cultivars of alfalfa (Medicago sativa L.), cold-tolerant Vernal and cold-sensitive Sonora, were grown under summer, winter, and dehardening conditions to determine the solubility characteristics and relationships of several dehydrogenases to cold tolerance. Soluble enzymatic proteins, extracted with three extractants, from lyophilized crown and root tissues, were separated by polyacrylamide disc gel electrophoresis. Gels assayed for glutamate, NAD-malate, NADP-malate, isocitrate, lactate, 6-phosphogluconate, and glucose-6-phosphate dehydrogenases showed quantitative differences in isoenzymes that were influenced by cultivar, extractant, and environmental differences. For both cultivars, enzyme activity was lowest during summer, increased in winter, and decreased during dehardening. Dehydrogenase activity, therefore, was closely associated with the fluctuations in soluble protein concentration, which were related to environmental changes and cold tolerance. Additional isoenzymes of isocitrate, lactate, and glucose-6-phosphate dehydrogenases were detected in the winter samples of both cultivars; however, most of the qualitative differences observed were generally due to the differential solubilities of isoenzymes in the three extractants. Comparison of data obtained from the use of frozen and unfrozen extracts indicated differential stabilities of the dehydrogenases to freezing in the different extractants. Glutamate, NAD-malate, and NADP-malate dehydrogenases were fairly stable to freezing whereas isocitrate, lactate, 6-phosphogluconate, and glucose-6-phosphate dehydrogenases were labile. Detectable levels of the latter dehydrogenases in frozen extracts were evident only in certain extracts of winter samples, indicating the importance of the nature of the extraction medium in protecting against enzyme denaturation. Since both cultivars showed similar changes in dehydrogenase activities at most times, the increased enzyme levels during winter coincided with increased levels of soluble protein and soluble sugars, which are indicative of the broad spectrum of metabolic changes involved in the attainment of the cold-tolerant state.
Workshop: Targeting mechanism of epigenetic factors

Epigenetic patterns provide an extra layer of gene regulation beyond the genomic sequence and play a critical role in the maintenance of cell-type specific gene expression programs. Disruption of epigenetic regulation can cause severe diseases including cancer. During the past few years, large amount of epigenomic data have been generated displaying significant epigenetic pattern changes across cell-types and in disease tissues. On the other hand, the targeting mechanism for epigenetic factors remains poorly understood. A fundamental question is to what extent epigenetic targeting is encoded in the genome. Unlike transcription factors, epigenetic factors typically do not directly interact with DNA and their targeting is associated with many weakly interactions. We have developed computational approaches to tackle this challenge and applied to prediction of genome-wide nucleosome positions and histone modification patterns from DNA sequence information. Our work has provided mechanistic insights into epigenetic targeting and can be used to develop tools to reverse specific disease-causing, aberrant epigenetic changes as a potential novel therapeutic approach for cancer and other diseases.
Application of cognitive apprenticeship model to a graduate course in performance systems analysis: A case study

This article reports a case study describing how the principles of a cognitive apprenticeship (CA) model developed by Collins, Brown, and Holum (1991) were applied to a graduate course on performance systems analysis (PSA), and the differences this application made in student performance and evaluation of the course compared to the previous semester. I analyzed the requirements for the CA learning environment and identified the contributions of instructor, students, and the course based on those requirments. I then applied the findings to create an authentic learning environment based on CA principles. In this case the students became performance consultants, immersed in practical application of the PSA content and methodology to authentic organizational performance issues provided by real clients. Finally, I compare student evaluation of the course to student evaluations in the previous semester, and report their responses to a set of open-ended questions concerning the application of CA principles.
Small Subunit Ribosomal RNA Sequences Link the Cause of Proliferative Gill Disease in Channel Catfish to Henneguya n. sp. (Myxozoa: Myxosporea)

Abstract In a previous study the small subunit ribosomal RNA (SSU rRNA) gene of Aurantiactinomyxon ictaluri, the actinosporean stage (actinospore) of the myxozoan associated with proliferative gill disease (PGD), was sequenced. In this study bath exposures of channel catfish Ictalurus punctatus to A. ictaluri isolated from the aquatic oligochaete Dero digitata were used to study the subsequent development of this parasite and to confirm the SSU rRNA gene sequences of each life stage. On day 7 postexposure, typical PGD organisms were observed in the gills, and at 3 months postinfection, cysts containing the newly identified myxozoan Henneguya sp. spores were observed in the gills. The sequence of the SSU rRNA genes of the actinospore and myxospore life stages demonstrated their identity. This is the first molecular evidence that A. ictaluri, isolated from D. digitata, can infect catfish and produce the typical PGD organisms in the gills. These data provide further proof that the actinospore A. ictaluri is ...
Inactivation of phosphoenolpyruvate carboxykinase by the guanosine nucleotide analogue, 5′-p-fluorosulfonylbenzoyl guanosine☆

Abstract Rat liver cytosolic phosphoenolpyruvate carboxykinase is inactivated by incubation with 0.84 mM 5′-p-fluorosulfonylbenzoyl guanosine, but is not appreciably affected by the adenosine analogue, 5′-p-fluorosulfonylbenzoyl adenosine, in correspondance with the known nucleotide specificity of this enzyme. Marked protection against inactivation by 5′-p-fluorosulfonylbenzoyl guanosine is provided (either in the presence or absence of divalent metal cation) by GTP or GDP but not by ATP or phosphoenolpyruvate. The inactivation appears to be due to covalent reaction since radioactive reagent remains associated with the enzyme after extensive dialysis and gel filtration on Sephadex G-25. These results are consistent with affinity labeling of the nucleotide binding site of phosphoenolpyruvate carboxykinase by the guanosine nucleotide analogue 5′-p-fluorosulfonylbenzoyl guanosine.
An efficient clustering algorithm using graphical techniques

This paper aims at an efficient, reliable and scalable density-based clustering algorithm. Using efficient techniques from computational geometry and computer aided geometric design such as the algorithms for range searching, closest pair searching and splines, we are able to derive a clustering algorithm with O(n /spl middot/ logn) in time complexity using O(n /spl middot/ log n/ log log n) in space. In contrast to other density-based algorithms, our algorithm overcomes the use of the parameters for the radius and the minimum number of points in the neighborhood. Comparisons between our algorithm and other known clustering algorithms are provided.
Microblogging in the Enterprise: A Few Comments are in Order

Popular social networking sites have revolutionized the way people interact on the Web. Researchers have studied social networks from numerous perspectives, mostly focusing on publicly available social networks and microblogging sites. Enterprises however have recently being adopting and utilizing microblogging services as part of their day to day operations. The goal of this paper is to study the topological properties of a corporate microblogging service, its dynamics and characteristics. Through an extensive analysis of enterprise microblogging data, we provide insights on the structural properties of the extracted network of directed messages sent between users of a corporate microblogging service, as well as the lexical and topical alignment of users. We compare our results to traditional, general purpose, online social networks and discuss the implications of our findings. To the best of our knowledge, this work is the first quantitative study of an enterprise microblogging service, its usage characteristics, and its derived social network based on replies between users.
What is the role of prosthesis insertion in esophageal carcinoma

We review our experience with 13 patients in whom esophageal dilation was used for palliation of malignant esophageal obstruction and with five patients treated with esophageal prostheses for malignant esophagorespiratory fistula. Twelve of the 13 patients with dilation alone received satisfactory palliation and were able to eat a soft or regular diet. Four of five patients with esophagorespiratory fistulas had esophageal dilation followed by insertion of a esophageat prosthesis and received good palliation. Endoscopic insertion of esophageal prosthetic devices has become increasingly popular as a palliative procedure, despite lack of controlled trials either proving efficacy of this therapy or comparing it to radiation therapy with or without dilation of the esophagus. The reported mortality and morbidity rates for esophageal prosthesis insertion are higher than those reported for radiotherapy. There is little to suggest that prostheses are better than or even equal to radiotherapy alone or radiotherapy and bougienage. We review the reported series (>2300 cases) of push-through prostheses insertions in esophageal cancer and compare prosthesis insertion to other therapy. The need for a carefully controlled trial of the different forms of therapy is emphasized, and guidelines for such a study are suggested.
A spreadsheet evaluation of nontraditional surface topology functional measures

Nontraditional functional measures derived from the zone distance measure and associated with form error are computed using a spreadsheet formulation. The functional measures seek to extricate the internal structure of the sample data and include the directional density function and related moments, directional distribution function, balance functional, and a touching point functional. A summary description of the spreadsheet implementation is provided and a detailed example is used to illustrate the geometric structure of the induced measures.
SU-E-J-13: A New Variable for Plan Quality Evaluation Based On Normal Tissue Sparing

Purpose: The dose dropping speed (DDS) in normal tissue was proposed to assess plan quality. It was tested in stereotactic radiosurgery (SRS) cases. Methods: The DDS was tested with a total 40 plans for 8 SRS cases. Dynamic conformal arc plans were generated for each case, with prescription dose to isodose levels (IDL) ranging from 50% to 90% with 10% increment to cover the PTV. Forty non-overlapping rind structures of 1mm thickness were created layer by layer from each PTV surface. The average dose in each rind was calculated and fitted with a double exponential function (DEF) of the distance from the PTV surface, which models the steep and moderate portions of the average dose curve in normal tissue. The parameter charactering the steep portion of the average dose curve in the DEF quantifies the DDS in the normal tissue receiving high dose. Provided that the prescription dose covers the whole PTV, a greater DDS indicates better normal tissue sparing. Results: Among all plans, the DDS was found to be the smallest for prescription of 90% IDL and reached a higher plateau region for prescription to 60% or 70%. The ratio of the highest slope to that of 90% prescription was 1.68±0.35. Analyzed with ANOVA, the DDS difference between the plans with prescription to 60% or 70% IDLS and those with prescription to 90% IDL were found significant (p<0.01). This can be attributed to the field size and penumbra slope change with different prescription levels. The trend became less pronounced with increasing PTV size due to less change of field profile for larger field size. Conclusion: A method was proposed to estimate dose dropping speed as a measure of plan quality. Based on this measure, prescriptions to 60% and 70% IDLs were found to provide best normal tissue sparing.
Blunted kaliuresis after an acute potassium load in patients with chronic renal failure.

Abstract Blunted kaliuresis after an acute potassium load in patients with chronic renal failure. We evaluated renal handling and plasma potassium (K) and aldosterone (PA) responses to acute oral K loading in 11 patients with tubulointerstitial renal disease (creatinine clearance 32 ± 5ml/min [SE]) and 13 control subjects (creatinine clearance 123 ± 5). After 4 days of a 10 mEq Na, 50mEq K diet, the subjects received 0.5mEq KCl/kg body weight. Prior to KCl there were no differences between the groups in plasma K or urinary K excretion (U K V). In the 4 hr following KCl, less of the load (13 ± 4%) was excreted by patients than control subjects (54 ± 5%; P Diminution de la kaliurese apres une charge potassique aigue chez des malades ayant une insuffisance renale chronique. Nous avons evalue l'excretion renale et les reponses du potassium (K) et de l'aldosterone (PA) plasmatiques a une charge de K aigue orale chez 11 malades atteints de nephropathie tubulo-interstitielle (clearance de la creatinine 32 ± 5ml/min [SE]) et chez 13 sujets controles (clearance de la creatinine 123 ± 5). Apres 4 jours d'un regime a 10mEq de Na et 50mEq de K, les sujets ont recu 0,5mEq KCl/kg poids corporel. Avant KCl, il n'y avait pas de differences entre les groupes en ce qui concerne le K plasmatique ou l'excretion urinaire de K (U K V). Au cours des 4heures suivant KCl, une fraction moindre de la charge (13 ± 4%) a ete excretee par les malades que par les sujets controles (54 ± 5%; P
The sine-Gordon equation in toroidal magnetic-fusion experiments

This paper presents a new nonlinear model which describes localized magnetohydrodynamic (MHD) modes in reversed-field pinch (RFP) experiments. To date, nearly all experimental and theoretical work in this area has relied on the use of Fourier decomposition of spatial variations as a function of time. Moreover, due to the complexity of this nonlinear problem, previous work has been restricted to the analysis of a relatively small number of modes. In contrast, the model studied in this paper, based on the damped-driven sine-Gordon (DDSG) equation, addresses the full nonlinearity, does not rely on Fourier decomposition, and does not require the range of the nonlinearity to be small. A specific consequence of working with the full nonlinearity is the existence of solitary waves in dispersive media. These solitary waves, a key part of the model, are used to describe the so-called slinky mode propagating in the plasma. A remarkable resemblance is seen between the waveforms obtained from experiments and the mathematical predictions of the new model.