cssi/SciSciGPT-SciSciNet huggingface dataset:
Expression and characterization of human mitochondrial ferredoxin reductase in Escherichia coli.

Ferredoxin reductase (Fd-reductase) supplies reducing equivalents obtained from NADPH to mitochondrial cytochrome P450 enzymes via the small iron-sulfur protein ferredoxin. Two cDNAs (differing by the presence or absence of an 18-bp insert in the coding region) for the human Fd-reductase were subcloned into a newly constructed general purpose expression vector, pΔblue; protein expression under control of the bacteriophage λpL promoter was then induced in Escherichia coli. Western blot analysis of subcellular fractions indicated that Fd-reductase protein expressed from both plasmids was present in both inclusion bodies and soluble fractions. However, only the form lacking the insert exhibited Fd-reductase activity. The active material was purified and was found to have electrophoretic, chromatographic, optical, and circular dichroism properties comparable to the bovine homologue. The apparent Km of the expressed protein for NADPH was determined to be 0.7 ± 0.1 μ m and the apparent Km for human ferredoxin was found to be 106 ± 8 n m. While yields of active enzyme were relatively low (~0.1 mg/liter of culture), the production of Fd-reductase in E. coli will allow structural and mechanistic studies of the enzyme and its interactions with ferredoxin.
Neomycin: a specific drug to study the inositol‐phospholipid signalling system?

Abstract Neomycin, an antibiotic previously thought to interact specifically with inositol-containing phospholipids, was found to inhibit IP3-mediated Ca2+ release from the intracellular stores of permeabilized insulinoma and liver cells. This inhibition could be relieved by increasing the IP3 concentration. Radiolabelled IP3 was found to bind tightly to columns prepared from neomycin covalently attached to glass beads. ATP was also bound by these colums. It is concluded that neomycin acts in biological systems as a weak anion exchanger and is therefore unsuitable for use as a specific tool to study the role of inositol phospholipids in intracellular signalling.
The effects of chronic vitamin A excess on bone remodeling in aged rats.

AbstractThis study was conducted to assess the effects of long-term ingestion of moderate excesses of vitamin A on trabecular bone remodeling in the fifth lumbar vertebral body of aged rats. Eighteen-month-old rats were fed diets with vitamin A content equal to the daily requirement (DR), 2-fold, and 5-fold the DR along with calcium content of either the DR or 0.3-fold the DR, for 14 months each. As expected, serum concentrations of 1,25-dihydroxyvitamin D were higher in the reduced than in the normal calcium intake groups (65.1 ± 2.4 SEM vs 47.8 ± 2.1 pg/ml, P < 0.001). Calcium balance was more positive at the higher than the lower calcium intake (5.7 vs 0.9 mg, P < 0.001) but was unaffected by vitamin A intake. Histomorphometric analysis of the fifth lumbar vertebral body revealed that the 2-fold but not the 5-fold excess in vitamin A intake resulted in a 15% increase in percentage of trabecular bone (P < 0.02). The low calcium diet depressed bone growth (total bone tissue) but did not affect percentage...
Heat transfer through the turbulent incompressible boundary layer on a flat plate

Abstract From the assumption that the dimensionless velocity profile in a turbulent incompressible boundary layer obeys the well-known universal profile it is shown that the boundary layer thickness, and the shear stress and eddy diffusivity variations through the thickness at any Reynolds number, may be derived. The resulting variations, expressed in dimensionless form, are shown to be only weakly dependent on Reynolds number. Using the additional assumption that the eddy diffusivities for momentum and heat are equal the energy equation is solved numerically to obtain the Stanton number variation with Reynolds number for several Prandtl numbers. Results are given for Prandtl numbers of 0.01, 0.1, 0.7, 1.0 and 10 for a number of different positions of a step temperature distribution on the flat plate.
A lunar libration point experiment

Abstract Photographs of the lunar libration point L4 were made during the lunar eclipse of 6 October 1968, using the 48-inch Schmidt telescope at Palomar Mountain, California. An area about 6.6° square was covered. Neither discrete objects nor clouds, associated with the L4 point, were found. The detection limit for discrete objects was at least 15th magnitude and probably 17th magnitude; for clouds, the limit was determined by short-term variations in the local pattern of night sky-glow.
CAP-subgroups in a direct product of finite groups

Abstract If a subgroup U of a finite group G has the property that either U H = U K or U ∩ H = U ∩ K for every chief factor H / K of G , then U is said to have the cover-avoidance property in G and is called a CAP-subgroup of G . It is well known that a subgroup U of a direct product G 1 × G 2 is determined by isomorphic sections S 1 of G 1 and S 2 of G 2 and by an isomorphism ϕ between those sections. We prove that whether U is a CAP-subgroup of G 1 × G 2 depends on the isomorphism ϕ , but not necessarily on the sections S 1 and S 2 . Equivalently, U is a CAP-subgroup of G 1 × G 2 if and only if U M ∩ G 1 is a CAP-subgroup of G 1 and U N ∩ G 2 is a CAP-subgroup of G 2 for all M G 2 and N G 1 . Consequently, subdirect subgroups and CAP-subgroups of direct factors have the cover-avoidance property.
Further Evidence on the Hain Scoring Method for the Bender-Gestalt Test

Seventy-six Bender-Gestalt protocols were scored utilizing the Hain Scoring Method. The subjects were young adult moderately or mildly mentally retarded females. Protocols were scored for Hain's 15 differentiating signs identifying brain damage: 37% of the rehabilitated group and 39% of the nonrehabilitated group received critical scores. Characteristics of the procedure and limitations of the study are discussed.
Granulocytic differentiation of HL-60 promyelocytic leukemia cells is associated with increased expression of Cul5

The human HL-60 promyelocytic leukemia cell line has been widely used as a model for studying granulocytic differentiation. All-trans retinoic acid (ATRA) treatment of HL-60 cells promotes granulocytic differentiation and is effective as differentiation therapy for patients with acute promyelocytic leukemia. The identification of genes that are transcriptionally regulated by ATRA has provided insight into granulocytic differentiation and differentiation therapy. The Asb-2 (ankyrin repeat SOCS box 2) gene has previously been identified as a transcriptional target in ATRA-treated HL-60 cells. The ASB-2 protein forms an E3 ubiquitin ligase complex with the proteins, Cul5, regulator of cullin 2 (ROC2), and elongin B and C. The purpose of this study was to determine if there is increased expression of Cul5 during granulocytic differentiation of HL-60 cells. To induce granulocytic differentiation, HL-60 cells were treated for 5 d with ATRA and differentiation was confirmed by examining superoxide anion production, nuclear morphology, and changes in the expression of CD11b, CD13, and CD15. Quantitative real-time RT-PCR was used to measure Cul5 mRNA expression and also the expression of other components of the E3 ubiquitin ligase (ASB-2, ROC2, elongin B and C). Granulocytic differentiation of HL-60 cells was associated with a 1.6-, 1.7-, and 23-fold statistically significant (P ≤ 0.05) increase in mRNA expression for Cul5, ROC2, and ASB-2, respectively. No significant change was found in elongin B and C mRNA expression. Using Western blot analysis, the expression of Cul5 protein was increased 6.5-fold with granulocytic differentiation of the HL-60 cells. Increased expression of multiple components of the Cul5-containing E3 ubiquitin ligase complex with ATRA treatment of HL-60 cells indicates that this complex may play an important role in granulocytic differentiation.
New World biogeography and the evolution of polychromatism: evidence from the bee assassin genus Apiomerus (Heteroptera: Reduviidae: Harpactorinae)

The crassipes and pictipes species groups of Apiomerus Hahn together contain 12 species, many with high intraspecific chromatic variability, which represent the majority of Nearctic species in this New World assassin bug genus. Because of their geographical distribution and their varying degrees of polychromatism, these two species groups provide a unique opportunity to study the evolution of polychromatism and analyse relationships among areas of endemism in the Nearctic, as well as determine the boundary between the Nearctic and Neotropical regions. The results of a morphology based phylogenetic analysis allowed investigation of these questions while also determining relationships among the 12 species in the two species groups. The crassipes and pictipes species groups were each supported as monophyletic and as sister taxa. Apiomerus rufipennis (Fallou) was not included in the original concept of the crassipes species group, but is shown here to be a member of the group. Apiomerus barrocoloradoi Forero, Berniker & Szerlip, which had been hypothesized previously to belong to the pictipes species group, is excluded from this group. Intraspecific polychromatism for each species was identified as being present in one of three states: no polychromatism; limited polychromatism; or polychromatism as discrete colour morphs. Limited polychromatism was here found to be the ancestral state for Apiomerus, and species with discrete colour morphs are restricted to the crassipes and pictipes species groups. Polychromatism appears to be a greatly homoplastic character within the genus. A Brooks parsimony analysis recovered distinct Nearctic and Neotropical clades. The Nearctic clade is divided between areas in the central and eastern U.S.A. and areas in the Western U.S.A. and Mexico. The Nearctic–Neotropical boundary for the taxa included in the analysis is along the Isthmus of Tehuantepec in southern Mexico.
Titanium–halide catalyst-precursors in sodium aluminum hydrides

Abstract The kinetics of absorption and desorption of hydrogen from NaAlH 4 have previously been shown to improve upon the addition of a catalyst-precursor such as TiCl 3 . In this paper we demonstrate that TiCl 2 , TiF 3 , and TiBr 4 all effectively improve sorption kinetics. Arrhenius data indicate that the catalyst precursors behave in essentially the same manner. Evidently the valency of Ti in the catalyst-precursor is inconsequential to the role of Ti in altering the kinetic mechanism. The formation of TiAl 3 on doping with TiCl 3 has been observed. The presence of TiAl 3 appears to contribute in part to the enhanced kinetics in these systems.
High-pressure alloying of potassium and iron: Radioactivity in the Earth's core?

[1] High-resolution x-ray diffraction provides evidence that potassium (K) alloys with iron (Fe) when the two pure elements are heated together at pressures above ∼26 gigapascals (GPa). Increases of 2–3% in volume of the e (hexagonal close packed: hcp) high-pressure phase of Fe can be attributed to the incorporation of ∼1 atomic% (∼7000 ppm by weight) K into Fe. Our results provide experimental support for predictions, derived from quantum mechanical calculations, that pressure can induce the alloying of K with Fe due to a change in the chemical-bonding character of K from alkaline- to transition-metal. Radioactive decay through the incorporation of 40K into the core could therefore be an important source of energy deep inside the Earth, helping to power the geodynamo and mantle dynamics.
Supplier selection problem: a comparison of the total cost of ownership and analytic hierarchy process approaches

Supplier selection and evaluation are arguably one of the most critical functions for the success of an organization. Several approaches exist in the literature to objectively evaluate suppliers, including analytic hierarchy process and total cost of ownership. Analytic hierarchy process provides a framework to cope with multiple criteria situations involving supplier selection, while the total cost of ownership is a methodology and philosophy, which look beyond just the price of a purchase to better understand and manage costs in selecting and maintaining relationships with suppliers. This paper illustrates the two approaches and provides a comparison.
Classification of Abelian quantum Hall states and matrix formulation of topological fluids.

We give a simple and unified treatment of quantum topological fluids such as the quantum Hall fluid. We show that the order in such fluids can be characterized by a symmetric matrix K, in terms of which various physical quantities can be determined. We construct K by a matrix iteration procedure which may be decomposed into two simple elementary steps. The hierarchy construction is shown to be contained in our matrix iteration construction. The relationship between the vortex basis and the dual electron basis is clarified. We also show that under certain mild assumptions the generalized hierarchy construction exhausts all possible Abelian fractional quantum Hall states. We identify and determine the topological quantity known as the shift. Our formalism may be relevant for recent experimental data on multilayered systems.
Enhancement of strength and ductility in ultrafine-grained T91 steel through thermomechanical treatments

We report on the microstructure and mechanical properties of T91 alloy subjected to different thermomechanical treatments (TMTs). Equal channel angular extrusion (ECAE) was performed at 23, 300, 625, and 700 °C. Mechanical strength of T91 alloy is enhanced after cold-ECAE at the expense of ductility. In comparison, the hot-ECAE process leads to less pronounced hardening but retention of ductility and work hardening ability. Microstructure analyses reveal that cold-ECAE has significantly reduced the average grain size, while hot-ECAE is more effective to refine and uniformly redistribute carbide nanoprecipitates. Post-ECAE annealing (500 °C/10 h) leads to reprecipitation of large carbide particles in cold-ECAE processed alloy, whereas the hot-ECAEed specimens retain smaller nanoscale carbide precipitates and uniform microstructure. A mechanism is proposed to explain the influence of TMT on the evolution of precipitates. Strengthening of T91 alloy is discussed through a modified model that considers the effects of dislocation density, grain size, and precipitation hardening.
Theoretical model for the formation of ion-pairs in seawater

Abstract Predictions of association constants for ion-pair formation in seawater were compared to measured constants as a test for the existence of ion-pairs. A fair agreement was obtained in most cases, although the theoretical electrostatic calculations indicate that significant chloride ion-pairing should occur which has not been observed in most experimental investigations.
Jeopardy: A Grandmother's Story

This article is written in the genre of creative nonfiction. It brings the reader into the dreaming, peridreaming, and waking mind of a grandmother whose normative expectations for her son's marriage and family disintegrate. It is neither an autoethnography nor a memoir. Its intents are (1) to unpack some of the consequences of an alternative child-raising ideology on three generations and (2) to widen the scope of symbolic interactionist writing and theory by embodying the tenets of SI rather than talking about them.
Les Atomes: a landmark book in chemistry

There have been occasions when the publication of a particular book has had a singular impact on the conceptual world of the chemist. Sometimes the publication occurs near the beginning of a major change in discourse, and sometimes more near the end. Jean Perrin published Les Atomes in 1913 as the culmination of a century-long controversy over the size and physical reality of atoms and molecules. After its publication almost all chemists and physicists agreed that atoms and molecules of the size we currently understand to be appropriate are real physical objects. The story of the background, development, publication, content and response to Les Atomes forms the text of this paper. The content of Les Atomes is also the basis for extended reflection on the philosophical significance of the work of Jean Perrin.
A heuristic algorithm for determining replacement policies in consecutive k -out-of- n systems

This article presents a heuristic algorithm for determining replacement policies in a discrete-time, infinite-horizon, dynamic programming model of a binary coherent system with n statistically independent components, and then specializes the algorithm to consecutive k-out-of-n systems. Costs arise when the system fails and when failed components are replaced. The objective is to minimize the long run expected average undiscounted cost per period. A companion article (Naval Res. Logistics 49 (2002) 288) develops a branch and bound algorithm for computing optimal policies. Extensive computational experiments on consecutive k-out-of-n systems find it effective when n≤ 40 or k is near n; however, the computations can be intractable when n > 40 and 2≤k < n-15, suggesting the need for a good heuristic. Computational experiments on consecutive k-out-of-n systems involving over 300,000 test problems find the heuristic of this article highly effective. For each n and k tested, its percentage error was under 2.53%, and its mean computation time on a 1700 MHz Pentium IV was under 0.24 s (the largest n in our experiments was 200).
Effect of AlN buffer layers on the surface morphology and structural properties of N-polar GaN films grown on vicinal C-face SiC substrates

Abstract We investigated the effect of AlN buffer layers on hexagonal hillock formation and the crystallinity of N-polar GaN films grown by metalorganic chemical vapor deposition on vicinal C-face SiC substrates misoriented toward 11 2 ¯ 0 > by 3.6° and 10 1 ¯ 0 > by 4°. As the source input group V/III ratio increased from 650 to 16310 and growth temperature was raised from 1100 °C to 1150 °C during AlN buffer layer growth on the substrates with 11 2 ¯ 0 > miscut direction, the threading dislocation (TD) density of the AlN buffer layers and subsequent N-polar GaN films decreased. TD density of AlN and GaN films grown on 10 1 ¯ 0 > misoriented substrates was higher in comparison to that grown on 11 2 ¯ 0 > miscut substrates. The hexagonal hillock density of the N-polar GaN films was reduced by increasing the AlN V/III ratio up to 16310 and decreasing the AlN thickness from 90 to 30 nm, indicating that nucleation of inversion domain occurs during AlN buffer growth. Hexagonal hillocks were completely suppressed in N-polar GaN films grown on both substrates when the growth temperature of the 30 nm thick AlN was increased from 1100 °C to 1150 °C at a V/III ratio of 16310.
Non-Invasive Measurement Techniques for Measuring Bilayers in Droplet-Interface-Bilayers

Phospholipids and membrane proteins are two of the fundamental building blocks of cell membranes in living organisms. These molecules are amphipathic and synthetic membranes made of phospholipids, called bilayer lipid membranes (BLMs), are used to understand the characteristics of a cell membrane. Studies of these BLMs have been performed on both solid support and liquid support systems. A droplet interface bilayer (DIB) is a liquid support system where a monolayer is formed around a water droplet placed in oil and a bilayer is formed when two of these droplets are placed in contact. For impedance measurements, electrodes are placed in the water on each side of the bilayer. The measurements first insure there is a bilayer and second to obtain information about the bilayer. In a DIB system the electrodes pierce the monolayer surrounding the droplet causing instabilities in the monolayer. This study focuses on a non-invasive technique for measuring the bilayer by using the electrodes to contact the monolayer around the droplets and take impedance measurements without piercing the monolayer.© 2009 ASME
'Boy' and 'Girl': The AIDS Risk Implications of Heroin and Cocaine Symbolism Among Injection Drug Users

The terms ‘boy’ and ‘girl’ are commonly used by injection drug users to refer to heroin, which produces a ‘down’ high, and cocaine, which produces an ‘up’ high, respectively. This paper examines th...
Post-Traumatic Stress Disorder in Episodic and Chronic Migraine

Objective.— To assess and contrast the relative frequency of self-reported post-traumatic stress disorder (PTSD) in patients with episodic migraine and chronic/ transformed migraine. Background.— Several risk factors have been identified as risk factors for chronification of headache disorders. Childhood abuse has been suggested as a risk factor for chronic pain in adulthood. In addition depression, as well as several other psychiatric disorders, are co-morbid with migraine. Recent data suggest that PTSD may be more common in headache sufferers than in the general population. Methods.— This was a prospective, pilot study conducted at a headache center. Adult subjects with episodic, chronic, or transformed migraine were included. Demographic information, depression history, body mass index (BMI), and headache characteristics were obtained. PTSD was assessed using the life events checklist (LEC) and the PTSD checklist, civilian version (PCL-C). We contrasted the data from episodicmigraineurs and chronic/transformed migraine participants (CM) and conducted multivariate analyses, adjusting for covariates. Results.— Of the 60 participants included, 91.7% were female with a mean age of 41.4 ± 12.5 years old. EM was diagnosed in 53.3% and CM in 46.7%. The mean BMI was not significantly different between groups. In contrast, the relative frequency of depression was significantly greater in subjects with CM (55.2%) than EM (21.9%, P = .016). There was no significant difference in the percentage of participants reporting at least 1 significant traumatic life event (LE) or in the mean number of traumatic LEs between EM and CM participants. However, the relative frequency of PTSD reported on the PCL in CM (42.9%) was significantly greater as compared to EM (9.4%, P = .0059. After adjusting for depression and other potential confounders, the difference remained significant P = .023). Conclusion.— PTSD is more common in CM than in episodic migraineurs. This suggests that PTSD may be a risk factor for headache chronification, pending longitudinal studies to test this hypothesis.
Mid-IR type-II interband cascade lasers and their applications

Type-II interband cascade lasers are efficient and compact mid-infrared (3-5 μm) light sources with many applications such as gas sensing and environmental monitoring. Significant progress toward such a goal has recently been made in terms of achieving low threshold current densities (e.g. ∼8 A/cm 2 at 80 K), high temperature operation (e.g. 325 K in pulsed and 217 K in cw modes), and continuous wave operation of single-mode distributed feedback (DFB) lasers. These DFB lasers have been integrated into laboratory spectrometers for detection of gases such as CH 4 and HCl. One laser was flown on a high-altitude balloon instrument and measured HCl profiles in the stratosphere as part of Aura satellite instrument validation. We review the recent progress of Sb-based mid-IR IC lasers and address the requirements for further improvements in their performance.
The Frequency and Cost of Treatment Perceived to Be Futile in Critical Care

Importance Physicians often perceive as futile intensive care interventions that prolong life without achieving an effect that the patient can appreciate as a benefit. The prevalence and cost of critical care perceived to be futile have not been prospectively quantified. Objective To quantify the prevalence and cost of treatment perceived to be futile in adult critical care. Design, Setting, and Participants To develop a common definition of futile care, we convened a focus group of clinicians who care for critically ill patients. On a daily basis for 3 months, we surveyed critical care specialists in 5 intensive care units (ICUs) at an academic health care system to identify patients whom the physicians believed were receiving futile treatment. Using a multivariate model, we identified patient and clinician characteristics associated with patients perceived to be receiving futile treatment. We estimated the total cost of futile treatment by summing the charges of each day of receiving perceived futile treatment and converting to costs. Main Outcome and Measure Prevalence of patients perceived to be receiving futile treatment. Results During a 3-month period, there were 6916 assessments by 36 critical care specialists of 1136 patients. Of these patients, 904 (80%) were never perceived to be receiving futile treatment, 98 (8.6%) were perceived as receiving probably futile treatment, 123 (11%) were perceived as receiving futile treatment, and 11 (1%) were perceived as receiving futile treatment only on the day they transitioned to palliative care. The patients with futile treatment assessments received 464 days of treatment perceived to be futile in critical care (range, 1-58 days), accounting for 6.7% of all assessed patient days in the 5 ICUs studied. Eighty-four of the 123 patients perceived as receiving futile treatment died before hospital discharge and 20 within 6 months of ICU care (6-month mortality rate of 85%), with survivors remaining in severely compromised health states. The cost of futile treatment in critical care was estimated at $2.6 million. Conclusions and Relevance In 1 health system, treatment in critical care that is perceived to be futile is common and the cost is substantial.
Modeling cognition in SI: Methodological issues

In this paper we discuss methodological issues pertaining to cognitive modeling of simultaneous interpretation. We briefly introduce the notion of cognition and efforts to model aspects of language-related processing. Previous work identifying cognitive processes in SI is sampled, and empirical SI studies are also mentioned. A rationale for modeling SI cognition follows, and relevant issues are sketched: whom to model, system dynamics, applicable technologies, and various possible processing scenarios. A discussion of evaluation considerations and requisite data resources follows. Throughout, we raise questions that must be addressed by the SI community, among both researchers and practitioners, if modeling SI is to be successfully realized in the future.
Fallopian tube and early cleavage in the mouse.

TECHNIQUES have been perfected for the culture in vitro of late two cell mouse ova into blastocysts in simple chemically defined conditions1,2. Attempts to obtain development from earlier stages have failed, unless the ova were cultured in organ cultures of the fallopian tube3,4. These results suggested that the fallopian tube provides some critical contribution necessary for the development of the mouse zygote into the late two cell stage. Nevertheless, it has been a common experience that when the mouse zygote is cultivated independently of the fallopian tube a few cleave to the two cell stage and then cease development5. It has now been shown6, however, that a high percentage of zygotes cleave to two cell stages and then cease development when cultured in Waymouth7 medium supplemented with ATP, deoxynucleosides and a feeder layer of irradiated HeLa cells. These experiments suggest that the initial development of the mouse zygote is dependent on a supply of exogenous factors, additional to those required by later stages.
The Need to Treat Childhood Obesity with Holistic Methods: Why Pediatric Endocrinologists Do Not Use Multifactorial Treatment

Childhood obesity can lead to serious health problems and has become a US health crisis. Although multiple factors contribute to childhood obesity, rarely is it treated in a multifactorial way. Pediatric endocrinologists are among the most qualified health professionals in this area, and their perceptions about multifactorial approaches, and the barriers prohibiting their use, for treating childhood obesity were explored. A mixed-method design composed of a qualitative and quantitative online survey administered to 63 pediatric endocrinologists, followed by in-depth semistructured telephone interviews of nine, indicated that pediatric endocrinologists do not believe they have the resources needed to successfully treat children with obesity in a multifactorial way and that they support the creation of a new professional role, obesity case manager.
Simultaneous Determination of Multiple Aldehydes in Biological Tissues and Fluids Using Gas Chromatography/Stable Isotope Dilution Mass Spectrometry☆

Biological oxidative stress has been associated with various degenerative disorders and disease states, and accurate and sensitive methods are needed to determine the extent of oxidation occurring in vivo. Peroxidation of polyunsaturated fatty acids forms complex mixtures of aldehydes and other breakdown products because various oxidants are involved and lipid composition is not uniform. Quantitative analysis of multiple lipid peroxidation products yields a more complete measure of biological oxidation than measurement of a single aldehyde, particularly when aldehydes exhibit marked differences in reactivity. This report describes extensions of an established gas chromatography/mass spectrometry method to include stable isotope dilution determination in tissue and plasma of three aldehydic products of lipid peroxidation: hexanal, nonanal, and 4-hydroxy-2-nonenal. Use of deuterated internal standards for each analyte improved precision and accuracy compared to a single internal standard for all three aldehydes. Improvements are attributed to differences in extraction and derivatization efficiencies for individual analytes owing to substantial differences in reactivity. Electron ionization of oxime-tert-butyldimethylsilyl derivatives gave greater specificity for detecting all three aldehydes than was possible using electron-capture ionization of O-pentafluorobenzyl oxime derivatives. Exchange of the deuterium label of [2,3-2H]HNE internal standard was determined to be minimal during the analyses.
Equilibrium unfolding of dimeric desulfoferrodoxin involves a monomeric intermediate: iron cofactors dissociate after polypeptide unfolding.

Here we report the conformational stability of homodimeric desulfoferrodoxin (dfx) from Desulfovibrio desulfuricans (ATCC 27774). The dimer is formed by two dfx monomers linked through beta-strand interactions in two domains; in addition, each monomer contains two different iron centers: one Fe-(S-Cys)(4) center and one Fe-[S-Cys+(N-His)(4)] center. The dissociation constant for dfx was determined to be 1 microM (DeltaG = 34 kJ/mol of dimer) from the concentration dependence of aromatic residue emission. Upon addition of the chemical denaturant guanidine hydrochloride (GuHCl) to dfx, a reversible fluorescence change occurred at 2-3 M GuHCl. This transition was dependent upon protein concentration, in accord with a dimer to monomer reaction [DeltaG(H(2)O) = 46 kJ/mol of dimer]. The secondary structure did not disappear, according to far-UV circular dichroism (CD), until 6 M GuHCl was added; this transition was reversible (for incubation times of 1 h) did the iron centers dissociate, as monitored by disappearance of ligand-to-metal charge transfer absorption, fluorescence of an iron indicator, and reactivity of cysteines to Ellman's reagent. Iron dissociation took place over several hours and resulted in an irreversibly denatured dfx. It appears as if the presence of the iron centers, the amino acid composition, and, to a lesser extent, the dimeric structure are factors that aid in facilitating dfx's unusually high thermodynamic stability for a mesophilic protein.
Stability of bulk negative-resistance material

The skin-effect limitation on an amplifier, obtained in a previous communication, is confirmed, but the amplifier is unstable beyond a critical length. The same instability mechanism discussed by Chawla and Coleman operates also in the oscillator case, but since saturation necessarily enters to limit the oscillation, it is not clear whether the full bulk of the material contributes to the output.
The Effect of Chemical Composition of Coal-Based Jet Fuels on the Deposit Tendency and Morphology

The formation of carbonaceous deposits on metal surfaces in fuel systems is a major concern for the development of advanced aircraft. This study examines the thermal stability behavior and carbon deposition and morphology of carbon deposits of thermally stressed coal-based jet fuels. These materials consisted of hydrotreated 1:1, 2:1, and 3:1 blends of refined chemical oil (RCO) with light cycle oil (LCO). Reactions were carried out in a thermal stressing reactor on an Inconel 718 surface at a 470 °C fuel temperature. Chemical compositions of jet fuel samples were determined using gas chromatography−mass spectrometry. In this work, it was found that jet fuels containing low amounts of sulfur and nitrogen and higher amounts of decalins and saturated cyclics gave lower carbon depositions at 470 °C. The quantity of carbon deposits formed was found to be independent of the RCO/LCO ratio. The morphology of carbon deposits and chemical composition were also examined. The RCO/LCO ratio in the blend changed the d...
Cloning of infectious adeno-associated virus genomes in bacterial plasmids

We describe the construction of two Escherichia coli hybrid plasmids, each of which contains the entire 4.7-kb DNA genome of the human parvovirus, adeno-associated virus (AAV) type 2. Because the AAV genome was inserted into the plasmid DNA using BglII linkers the entire virus genome can be recovered by in vitro cleavage of the purified recombinant plasmid. Transfection of these recombinant DNAs into an adenovirus-transformed human cell line in the presence of helper adenovirus resulted in efficient rescue and replication of the AAV genome and production of fully infectious virus particles. These AAV-plasmid recombinant DNA molecules should be useful both for site-specific mutagenesis of the viral genome and to study the potential of AAV as a eukaryotic vector.
PARENCHYMAL BRAIN METASTASES FROM ADENOCARCINOMA OF PROSTATE

Two patients with parenchymal brain metastases from adenocarcinoma of the prostate (CaP) are presented. Both patients had the diagnosis made antemortem by biopsy, and tumor immunoreactivity for prostatic phosphatase and prostate specific antigen confirmed prostatic origin. Brain metastases from prostatic adenocarcinoma are unusual, occurring in only 0.2 per cent of all patients with CaP. Patients present with symptoms of motor dysfunction, headache, and seizures. The mean age at presentation of brain metastases from CaP is fifty-nine years old, which is younger than most patients with CaP. The majority of patients die within weeks after diagnosis. Craniotomy with tumor debulking, radiation therapy, and androgen deprivation may be useful in prolonging survival. All reported cases of CaP metastatic to brain have been histologically moderately differentiated or poorly differentiated. The periprostatic venous plexus is considered the most likely route of tumor spread to the brain.
Hybrid approach for optical quantum computing

We describe a hybrid approach to quantum computing in which linear optical elements are used to perform the logic operations while relatively small nonlinear effects are used to avoid the need for ancilla photons
Nanoengineered PtVFe/C Cathode Electrocatalysts in PEM Fuel Cells: Catalyst Activity and Stability

The understanding of factors controlling electrocatalytic activity and stability of carbon-supported multimetallic catalysts is essential for advancing the design of fuel-cell electrocatalysts for oxygen reduction. The structural and compositional changes of trimetallic PtVFe/C catalysts have been investigated by several techniques, including XRD, X-ray absorption fine structure (XAFS), and inductively coupled plasma (ICP) analyses, in addition to electrochemical and fuel-cell performance tests. The investigation aims at understanding whether the base metals incorporated into the multimetallic catalysts are stable and how the base metals in the Pt-alloy are stabilized mechanistically. Changes are detected for the lattice properties and the composition of the base metals in the PtVFe nanoparticles after long-term exposure to air, after thermal treatment at different temperatures, and after use in proton-exchange membrane (PEM) fuel cells. These changes show certain correlations with the structure, activity, and stability of the catalysts. The fcc alloy phase is found to be predominant for catalysts treated at low temperature, but changes to a tetragonal-type alloy phase when the catalysts are treated at a higher temperature. In the low-temperature-treated catalyst, Fe has more bonds with O atoms, whereas in the high-temperature-treated catalyst, Fe has fewer O neighbors and FeFe bonds are detected. Analysis of the catalysts after testing in fuel cells indicates that the percentage of iron oxide is reduced, reflecting the propensity of dissolution of Fe oxide in the electrolytes. The smaller lattice parameter for the higher-temperature treated catalyst is considered to be an important factor in determining the catalyst stability under conditions related to fuel-cell operation.
An enhanced LQ adaptive VAr unit controller for power system damping

Static VAR compensators have been installed in power systems primarily to function in the steady state regulation of voltage levels or reactive power flows. More recently however there has been much interest in utilizing these devices to improve the dynamic performance of power systems. This paper presents an adaptive linear quadratic Gaussian control strategy for static var systems to enhance power system damping and stability. The control strategy uses only local information to dampen oscillatory modes present in the network. The controller calculates an appropriate value of VAr unit susceptance to present to the network at each sampling instant. The calculation of the appropriate susceptance value is based on a reduced-order model of the power system which is obtained on-line by a least squares identification procedure. The controller consists of three main components: an identifier, an adaptive observer, adn an adaptive LQG regulator. The identifier users a recursive least squares type of algorithm to fit a linear, discrete transfer function model to a sequence of input and output signals obtained from the power system. This results in a reduced-order approximation to the actual power system. For this study, VAr unit susceptance is used as the input signal and bus frequency deviation is used as the output signal. The coefficients of the identified transfer function are then sent to both the adaptive observer and the adaptive regulator. The observer is an observable-cannonical representation of the system and it calculates a state vector representing system dynamics.
A thin slice of violence: distinguishing violent from nonviolent sex offenders at a glance

A growing body of literature in evolutionary psychology suggests that person perception processes are adaptively tuned. The current investigation tested the hypothesis that people would be able to detect a propensity for violence in other people, based only on a brief glance at their face. Participants estimated the propensity for violence in 87 registered sex offenders after seeing photos of them for 2 s each. Estimated likelihood of violence was significantly related to actual violent history, suggesting that violent tendencies can be accurately inferred from a brief look at a person's face. Cues indicative of high masculinity and high levels of male sex hormones (heavy brow, general facial masculinity, high physical strength, younger age) were related to accurate judgments. Other cues such as facial emotion and good grooming were not associated with an actual history of violence, but nevertheless correlated with raters' judgments. Although there were no sex differences in accuracy, on average women thought targets were more violent than men did. Findings speak to the accuracy and efficiency with which people can detect potential threats to physical well-being.
Toward Complexity Measures for Systems Involving Human Computation

This paper introduces the Human Oracle Model as a method for characterizing and quantifying the use of human processing power as part of an algorithmic process. The utility of this model is demonstrated through a comparative algorithmic analysis of several well-known human computation systems, as well as the definition of a preliminary characterization of the space of human computation under this model. Through this research, we hope to gain insight about the challenges unique to human computation and direct the search for efficient human computation algorithms.
A Framework for Predicting Query Response Time

In a typical OLTP environment, emphasis has been given on promising Service level Agreements (SLAs) for perceived query elapsed response time; the SQL queries are tested on the small size of database which may be a fraction of the production database. As time progresses the database grows and the earlier optimized queries may not hold SLA anymore. Once the application is deployed, it becomes difficult to modify the application or alter the production system. In this paper, we have discussed a framework for predicting the SQL query response time with growth of the database while being transparent to the production hardware, storage subsystem and DB Server. We have discussed various factors which can impact query response time and are also affected by the increase in the data size. We have presented a theoretical model for predicting the elapsed response time of SQL queries and also discussed a case study of Oracle 10g for implementing the proposed frame work
Modeling of coupled TSVs in 3D ICs

This paper presents analytical formulas to extract an equivalent circuit model for coupled through silicon via (TSV) structures in a 3D integrated circuit. We make use of a multiconductor transmission line approach to model coupled TSV structures. TSVs are embedded in a lossy silicon medium, hence they behave as metal-insulator-semiconductor (MIS) transmission lines. The models we present can accurately capture the transition between slow-wave and dielectric quasi-TEM modes, which are characteristic for MIS transmission lines, as well as the metal-oxide-semiconductor (MOS) varactor capacitance. The results are validated against 2D quasi-static simulations and 3D full-wave electromagnetic simulations. The derived equivalent circuit models can easily be applied in circuit simulators to analyze crosstalk behavior of TSVs in a 3D integrated system.
How to use Helicobacter pylori testing in paediatric practice.

Helicobacter pylori is a slowly growing, gram negative microaerophilic bacterium that colonises the gastric mucosa. Cross-sectional epidemiological studies from both developed and developing countries suggest that the prevalence of H. pylori infection worldwide is declining, and may even be less than 10% in ‘westernised’ countries.1 ,2 H. pylori infection is acquired during the first decade of life and infection usually persists without treatment. Spontaneous clearance has been reported, although co-incidental antibiotic exposure may influence such ‘clearance’. H. pylori is the causative agent for diseases including peptic ulcer disease (PUD), chronic gastritis, gastric mucosa associated lymphoid tissue lymphoma and is the single-most important risk factor for developing gastric cancer.3 ,4 Putative extraintestinal associations have included refractory iron deficient anaemia, short stature and idiopathic thrombocytopenic purpura, although data supporting these associations in children must be interpreted with caution.4 ,5 The majority of children infected with H. pylori are asymptomatic. Following successful treatment, the risk of true reinfection in childhood is extremely low, at least in developed countries.6 Recrudescence describes re-colonisation with the same strain within 12 months, while re-infection refers to colonisation with a new strain, more than 12 months after eradication. Clinicians must carefully bear in mind these salient aspects of the pathogenesis and natural history of H. pylori- associated diseases as they consider whether testing their patients for H. pylori is indicated. ### Investigations for H. pylori The primary indication for investigation in children remains to diagnose the cause of significant symptoms and not simply to detect the presence of H. pylori . Testing for H. pylori is not helpful unless it alters clinical management, and consideration of the age-related pre-test probability of particular diseases (rather than infection alone) is essential. There remain certain scenarios in which screening for the presence of H. pylori is not absolutely indicated but may …
Optimizing Military Capital Planning

Planning United States military procurement commits a significant portion of our nation's wealth and determines our ability to defend ourselves, our allies, and our principles over the long term. Our military pioneered and has long used mathematical optimization to unravel the distinguishing complexities of military capital planning. The succession of mathematical optimization models we present exhibits increasingly detailed features; such embellishments are always needed for real-world, long-term procurement decision models. Two case studies illustrate practical modeling tricks that are useful in helping decision makers decide how to spend about a trillion dollars.
Cerebral metabolism and circulatory arrest: Effects of duration and strategies for protection

Hypothermic total circulatory arrest (CA) is commonly used to facilitate repair of complex congenital heart defects. However, the "safe" period of CA remains to be defined. Extended periods of hypothermic total circulatory arrest may impair cerebral metabolism and cause ischemic brain injury. This study defines the relationship between increasing durations of CA at 18 degrees C and cerebral metabolism, and examines the protective value of topical cooling of the head or continuous "trickle" flow (5 to 10 mL.kg-1.min-1). Thirty-three 1-week-old piglets were randomized to six experimental groups: control; 15, 30, or 60 minutes of CA; 60 minutes of CA with topical cooling of the head; and 60 minutes of trickle flow. Animals were placed on cardiopulmonary bypass (CPB) at 100 mL.kg-1.min-1 and cooled to 18 degrees C. After the experimental period of CA or trickle flow (or 60 minutes of CPB at normal flow for the control group), animals were rewarmed to 37 degrees C and weaned from CPB. Data were obtained before and immediately after CPB at 37 degrees C, and before and immediately after the experimental period at 18 degrees C. Parameters measured included cerebral blood flow by xenon 133 clearance, arterial and sagittal sinus blood gases, and cerebral metabolism. Hypothermic total circulatory arrest caused an impairment of cerebral metabolism that was directly proportional to CA duration (r2 = 0.73; p = 0.0001), and recovery of metabolic function after 60 minutes of CA improved more than 50% if the head was packed in ice.(ABSTRACT TRUNCATED AT 250 WORDS)
Temperature effect on physical and chemical properties of secondary organic aerosol from m -xylene photooxidation

Abstract. The chemical and physical differences of secondary organic aerosol (SOA) formed at select isothermal temperatures (278 K, 300 K, and 313 K) are explored with respect to density, particle volatility, particle hygroscopicity, and elemental chemical composition. A transition point in SOA density, volatility, hygroscopicity and elemental composition is observed near 290–292 K as SOA within an environmental chamber is heated from 278 K to 313 K, indicating the presence of a thermally labile compound. No such transition points are observed for SOA produced at 313 K or 300 K and subsequently cooled to 278 K. The SOA formed at the lowest temperatures (278 K) is more than double the SOA formed at 313 K. SOA formed at 278 K is less hydrophilic and oxygenated while more volatile and dense than SOA formed at 300 K or 313 K. The properties of SOA formed at 300 K and 313 K when reduced to 278 K did not match the properties of SOA initially formed at 278 K. This study demonstrates that it is insufficient to utilize the enthalpy of vaporization when predicting SOA temperature dependence.