cssi/SciSciGPT-SciSciNet huggingface dataset:
Polyoxometalate [γ-SiW10O34(H2O)2]4− on MCM-41 as catalysts for sulfide oxygenation with hydrogen peroxide

Abstract The polyoxometalate (POM) catalyst, [γ-SiW10O34(H2O)2]4−, was introduced into the pores of both as-synthesized (I) and amine functionalized MCM-41 (II). The resultant catalysts were characterized with powder X-ray diffraction, nitrogen sorption, and diffuse-reflectance UV–vis spectroscopy. Both catalysts were tested for reusability through repeated catalytic conversions of methyl phenyl sulfide to methyl phenyl sulfone with hydrogen peroxide. While the physisorbed catalyst (I) exhibits steadily decreasing turnover frequency (TOF), the POM catalyst supported on MCM-41 functionalized with a protonated amine (II) exhibits markedly improved reusability. This chemisorbed catalyst effectively showed no change in TOF between the second (21) and the sixth reactions (22). Additionally, sulfoxidations with catalyst II were investigated with a small set of substrates focusing on compounds including dibenzothiophene, which serves as a model refractory sulfide.
Foundations of criminal justice

Owen, S. S., Fradella, H. F., Burke, T. W., & Joplin, J. (2012). New York: Oxford University Press. ISBN-13 978-0-195-38732-2. pp. 464, pbk.I have finally found a textbook for introductory criminal...
Seismicity of Southwestern Yukon, Canada, and its relation to slip transfer between the Fairweather and Denali fault systems

Abstract Several researchers have postulated the existence of a fault (termed the Connector fault) that transfers slip from the Fairweather to the Denali fault systems in order to match the observed regional variations in fault slip and GPS deformation. Earthquake locations, seismic moment tensor information, and gravity data presented in this study suggest that the Connector fault is an active seismogenic structure that extends from the Fairweather fault near Hubbard Glacier to the intersection of the Duke River and Totschunda fault systems. Seismicity and potential field data also suggest the existence of an east–west trending cross structure between the Totschunda and Denali faults just north of 62°N that appears to be taking up compressional deformation similar to the Duke River fault system to the south. The intersection of this cross structure with the Totschunda fault occurs near the termination of the 2002 Denali fault mainshock rupture zone.
Beyond Ethical Frameworks: Using Moral Experimentation in the Engineering Ethics Classroom

Although undergraduate engineering ethics courses often include the development of moral sensitivity as a learning objective and the use of active learning techniques, teaching centers on the transmission of cognitive knowledge. This article describes a complementary assignment asking students to perform an ethics “experiment” on themselves that has a potential to enhance affective learning and moral imagination. The article argues that the focus on cognitive learning may not promote, and may even impair, our efforts to foster moral sensitivity. In contrast, the active learning assignments and exercises, like the ethics “experiment” discussed, offer great potential to expand the scope of instruction in engineering ethics to include ethical behavior as well as knowledge. Engineering ethics education needs to extend beyond the narrow range of human action associated with the technical work of the engineer and explore ways to draw on broader lifeworld experiences to enrich professional practice and identity.
Systematic errors in nulling interferometers.

Nulling interferometers combine on-axis suppression with high angular resolution, making them ideal instruments for the direct detection of faint planets close to their parent star. Analysis is developed to show that it is systematic errors, resulting from fluctuations in the null depth, that drive the instrument performance. A second-order combination of amplitude and phase errors is the dominant contributor. In the calculated example, the detection of an Earthlike planet around a Sunlike star at 15 pc requires that the arms of the interferometer must be phased to within ∼1.5 nm and have their amplitudes matched to ∼0.1%.
Parathyroid hormone and phosphaturia.

In 1911, Greenwald reported that urinary phosphate was significantly decreased in parathyroidectomized dogs (3). He was the first to suggest a link between the observed drop in phosphate excretion and the removal of the parathyroid glands. Sixty-four years later, the mechanism by which parathyroid hormone (PTH) enhances phosphaturia is still largely speculative. In the last ten years many investigators have reported that PTH, in addition to its phosphaturic effect, increases sodium and bicarbonate excretion, raises the pH of the proximal tubule fluid and of the urine, produces a mild diuresis and a systemic metabolic acidosis. These results suggest that PTH may inhibit H+ ion secretion in the renal tubules. Indeed, if one assumes that monovalent phosphate is more permeable or more readily transported than divalent phosphate, one could explain the phosphaturia as follows: a rise in intraluminal pH would depress phosphate reabsorption simply by reducing the monovalent to divalent phosphate ratio in the renal tubules. Two essential elements of this hypothesis need to be firmly established before it can be accepted: 1) monovalent phosphate is more readily transported than divalent phosphate; 2) PTH inhibits H+ ion secretion in renal tubules. We undertook these studies to test the validity of both postulates (2, 3).
Bedform transport rates for the lowermost Mississippi River

[1] New methods of data collection and processing are developed to provide quantitative, reach-scale measurements of bedform transport mass within the tidally influenced Mississippi River. A multibeam swath profiler was used to collect daily bathymetry over a range of water discharges, and bed elevation changes induced by dune migration are measured. These values are coupled with bulk physical properties of the bed sediment to constrain mass flux, and annual bedform transport is estimated at 2.2 x 10 6 metric tons (MT). The total annual sand flux from the Mississippi River, calculated by combining measured bedform transport rates and suspended sediment flux, is estimated to be 20 x 10 6 MT. Survey data also provide information about the spatial distribution of dunes across the channel bottom. Straight reach segments are commonly mantled by dunes for the entire cross section, while bends are typically areas of focused scour devoid of bedforms. Presumably, any sediments associated with migrating dunes are propelled into suspension within bends before redepositing in the subsequent straight reach. Movement via suspension is therefore an important component for the downriver transport of bed materials in the lower Mississippi River.
Thresholding in a calculation algorithm for fast approximation of wavelet transform

Wavelet transform has been widely used in many signal and image processing applications such as edge detection and data compression. For applications that tolerate a slight compromise in accuracy for faster speed, a fast approximation of wavelet transform is favorable. In this paper we propose a simple yet effective algorithm for fast wavelet transform. The use of fixed point numbers simplifies the hardware design and computational complexity than the use of a floating point arithmetic unit. Calculations are further reduced using our thresholding-in-calculation (TIC) technique to omit calculations of small terms that are negligible to the accumulated sum. The TIC technique basically determines whether a multiplication followed by an addition shall be executed using a look-up table with the quantized magnitude of multiplication operands as input parameters. Knowing the levels of quantization, any combination of the quantized multiplication operands can approximate the product and be compared to a predetermined threshold value. If the approximated product is greater than or equal to the threshold value, the corresponding entry in the look-up table is marked for multiplication; otherwise, no multiplication will be executed. Our simulation results show that our approximation algorithm is effective for wavelet transform of audio signals. In addition, when our algorithm is applied to a simple wavelet based edge detection algorithm, the detection result is almost the same as the one using precise calculation of the wavelet transform.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Small Ubiquitin-like Modifier (SUMO) Isoforms and Conjugation-independent Function in DNA Double-strand Break Repair Pathways

Small ubiquitin-like modifier (SUMO) proteins act in DNA double-strand break (DSB) repair, but the pathway specificity of the three major isoforms has not been defined. In experiments in which we depleted the endogenous SUMO protein by RNAi, we found that SUMO1 functioned in all subpathways of either homologous recombination (HR) or non-homologous end joining (NHEJ), whereas SUMO2/3 was required for the major NHEJ pathway, called conservative NHEJ, but dispensable in other DSB repair pathways. To our surprise, we found that depletion of UBC9, the unique SUMO E2 enzyme, had no effect in HR or alternative NHEJ (Alt-NHEJ) but was required for conservative NHEJ. Consistent with this result, both non-conjugatable mutant and wild-type SUMO1 proteins functioned similarly in HR and Alt-NHEJ. These results detail the functional roles of specific SUMO isoforms in DSB repair in mammalian cells and reveal that SUMO1 functions in HR or Alt-NHEJ as a free protein and not as a protein conjugate.
Advancing HIV Prevention Among Multiethnic Vulnerable Youths: Ethnoracial and Gender Differences

The need for the evaluation of community-based HIV prevention interventions among at-risk ethnoracial minority youth is warranted. A 5-day peer-led intervention was conducted among 201 at-risk youth aged 12 to 22 years old. We assessed ethnoracial and gender differences in sexual health knowledge, intention and ability to practice safe sex pre and post intervention. Participants were 57% male with a mean age of 16 years (50% Latino, 28% white, and 22% black). While participants in all ethnoracial groups showed improvement post intervention, black participants improved significantly less than whites in their intention to use condoms and HIV knowledge. Differences varied by baseline response. Results indicated that interventions may need enhancement in order to have a greater impact on ethnoracial minority youth.
Preparative scale isolation of galactosylhydroxylysine.

Abstract A method is described for the isolation and purification of gram quantities of the hydroxylysine-monosaccharide from commercially available marine sponge. The procedure utilized alkaline hydrolysis followed by purification by ionexchange chromatography and gel filtration. Compositional analysis indicated that the final product contained only galactose, hydroxylysine, and HCl which were present in equimolar quantities and comprised 94% of the dry weight. This preparation has been utilized as a substrate for the assay of UDP-glucose:collagen glucosyltransferase (EC 2.4.1.66) of human platelets.
A monoclonal antibody against CD148, a receptor-like tyrosine phosphatase, inhibits endothelial-cell growth and angiogenesis.

Angiogenesis contributes to a wide range of neoplastic, ischemic, and inflammatory disorders. Definition of the intrinsic molecular controls in angiogenic vessel growth promises novel therapeutic approaches for angiogenesis-related diseases. CD148 (also named DEP-1/PTPη) is a receptor-like protein tyrosine phosphatase that is abundantly expressed in vascular endothelial cells. To explore a role of CD148 in endothelial vessel formation, we generated a monoclonal antibody, Ab1, against the ectodomain sequence of CD148 and examined its effects on endothelial-cell growth and vessel formation. Here we report that a bivalent, but not a monovalent, form of the Ab1 antibody inhibits endothelial-cell growth and blocks angiogenesis in mouse cornea in vivo. We further demonstrate that (1) bivalent Ab1 arrests cell-cycle progression of CD148-transfected CHO cells at G0/G1 phase, (2) coexpression of catalytically inactive CD148 mutants attenuates the Ab1-cell growth inhibition, and (3) bivalent Ab1 suppresses phosphorylation of ERK1/2 kinases and Met tyrosine kinase as activated CD148 does, with an increase in CD148-associated tyrosine phosphatase activity. Taken together, these findings demonstrate that Ab1-induced ectodomain oligomerization arrests endothelial-cell growth through catalytic activity of the CD148 cytoplasmic domain. The present study defines CD148 as a valuable molecular target for antiangiogenesis therapy.
Optical fibers for magneto-optical recording

Two schemes are discussed for using single mode polarization preserving fibers in magneto-optic recording heads. The use of fibers could lead to new designs for compact, lightweight magneto-optic recording heads. Supporting experimental results are reported.
Alterations in lipid composition and fluidity of liver plasma membranes in copper-deficient rats.

In view of the importance of membrane fluidity on cell functions, the influence of phospholipid acyl groups on membrane fluidity, and the changes in lipid metabolism induced by copper (Cu) deficiency, this study was designed to examine the influence of dietary Cu on the lipid composition and fluidity of liver plasma membranes. Male Sprague-Dawley rats were divided into two dietary treatments, namely Cu deficient and Cu adequate. After 8 weeks of treatment, liver plasma membranes were isolated by sucrose density gradient centrifugation. The lipid fluidity of plasma membranes, as assessed by the intramolecular eximer fluorescence of 1,3-di(1-pyrenyl) propane, was significantly depressed by Cu deficiency. In addition, Cu deficiency significantly reduced the content of arachidonic and palmitoleic acids but increased the docosatetraenoic acids of membrane phospholipids. This alteration in unsaturated phospholipid fatty acid composition, especially the large reduction in arachidonic acid, may have contributed to the depressed membrane fluidity. Furthermore, Cu deficiency also markedly altered the fatty acid composition of the triacylglycerols associated with the plasma membranes. Thus, the lipid composition and fluidity of liver plasma membranes are responsive to the animal's Cu status.
A multiprogramming operating system for the TI980A

The University of Wyoming Computer Science Department has developed several versions of a multiprogramming operating system for research and for student use. This paper describes the background of the systems and the hardware facilities available. Major emphasis is placed on the message driven system and implementation problems presented by the hardware. The description includes the core-resident nucleus, the input/output communications, the file system and the high-level operating system.
Dependency and Development in a Globalized World: Looking Back and Forward

The principles of analysis proposed 40 years ago by Cardoso and Faletto in Dependency and Development in Latin America provide a fruitful way to understand divergent patterns of development in the contemporary era of globalization. This set of analytic principles combines a focus on distinct modes of national insertion into the global economy with a focus on the balance of domestic class forces, the capacity of state institutions, and contingent choices by political actors to explain the contrasting developmental fortunes of countries. The contributors to this special issue demonstrate the vitality of these principles by harnessing them to the dual task of explaining how countries respond to the challenges of globalization and the consequences of these responses. The critical, macroscopic, and possibilistic approach to political economy taken by the contributors offers an exciting and powerful way to understand the problems of development in our globalized world.
Game-based pursuit evasion for nonholonomic wheeled mobile robots subject to wheel slips

Pursuit-evasion (P-E) problem has been studied as a noncooperative zero-sum game in homicidal chauffer problem in 1960s and in the game of two identical cars most recently. The capture conditions i...
Process Analysis and the Neoclassical Theory of Production

This chapter focuses on process analysis and the neoclassical theory of production. Any analytical science can study only partial processes, that is, only slices of actuality. Every analytical process, therefore, can be but a partial process. To determine such a process, an analytical boundary is required. This boundary must include the duration of the process and the geographical frontier, which separates the process from the rest of actuality at all times. What an analytical process does can be described only by listing everything that crosses its frontier and at what time. To study what happens inside an analytical process, the process must be divided into other processes by drawing new boundaries. In drafting the list of the elements that cross the frontier, it must be kept in mind that a partial process being an artificial slice of actuality, such a process is inexistent both before the origin of its duration, t = 0, and after the end of that duration, t = T .
Targeted disruption of inducible 6-phosphofructo-2-kinase results in embryonic lethality.

Abstract Inducible 6-phosphofructo-2-kinase (iPFK-2; PFKFB3) produces fructose-2,6-bisphosphate (F2,6BP), which is a potent allosteric activator of 6-phosphofructo-1-kinase (PFK-1), the rate-limiting step in glycolysis. iPFK-2 functions as an activator of anaerobic glycolysis within the hypoxic microenvironment of growing tumors. The early embryo is challenged similarly since the process of vasculogenesis does not begin until after embryonic day 7. We hypothesized that iPFK-2 expression is essential for the survival of the growing embryo. First, we cloned the mouse homolog of iPFK2 and found that it is abundantly expressed in cortical neurons, epithelial cells, and secretory cells of the choroid plexus, pancreas, and adrenal gland of the adult mouse. Using gene targeting, we then disrupted exons 3–7 of the mouse iPFK2 gene, which encode the substrate binding site. No full-term homozygous iPFK-2−/− progeny were produced from 11 F7 iPFK-2+/− crosses and no homozygous iPFK-2−/− embryos were detected after 8 days of embryogenesis.
Selling Nostalgia: Mad Men, Postmodernism and Neoliberalism

Postmodernity, the cultural mode of neoliberalism, reduces history to a set of discourses with the concomitant assertion that the individual’s knowledge of the real emerges from an engagement with images of the real The economic structures of neoliberalism encourage rugged individualism, self-reliance, and assert a spurious gender equality. Mad Men, a contemporary media product situated in media-derived nostalgia demonstrates how audiences read the past through the postmodern, neoliberal discourse of style. These readings encourage an ahistorical understanding of gender and class that reinforces neoliberal suppression of people as members of political classes.
Percutaneous balloon pulmonary valvuloplasty

Percutaneous balloon pulmonary valvuloplasty (BPV) was performed in 18 consecutive patients with valvular pulmonary stenosis (PS) with no associated cardiac defects. The patients were 11 months to 19 years of age. The balloon was positioned across the pulmonary valve and inflated to pressures of 80, 100, and 120 pounds/square inch (psi). Each inflation lasted approximately 10 seconds. Peak systolic pulmonary valve gradient (delta P) and cardiac output were measured before and 15 minutes after BPV. There was no change in cardiac output, but all patients had an improved delta P. The prevalvuloplasty delta P was 81 +/- 31 mm Hg, decreasing to 23 +/- 11 mm Hg after BPV (p less than 0.01). The right ventricular peak systolic pressure decreased from 106 +/- 31 to 50 +/- 12 mm Hg (p less than 0.01). No pulmonary regurgitation was noted after BPV. The balloons were 12 or 15 mm in diameter, chosen according to the diameter of the pulmonary valve anulus. Pressures of 100 to 120 psi were required to achieve full inflation of the balloons. BPV also was performed in a patient with tetralogy of Fallot. Subsequent total repair provided an opportunity to observe the mechanism of the dilatation. Evidence of a small tear alongside the anterior valve raphe was noted. BPV induced a significant decrease in delta P and may offer an alternative method for treating PS.
The Sojourner Syndrome: An Interpretive Framework for Understanding Poor Black Women's HIV Risk

This study examines how the intersection of race, class, and gender influence HIV risk among 50 black women living in a poor urban community in Atlanta—the Bluff. The study posits that an intersectional approach to examining the dynamic interaction of race, class, and gender tells us more about disproportionate HIV rates among Black women than do statements about lifestyle choices. The study also applies an interpretive framework, the Sojourner Syndrome, to examine how these marginalized Black women resist, disrupt, and/or transform these intersecting obstacles to find resilience. The theory reframes the issue of HIV risk and poor Black women to make the role of social oppression more transparent.
Linear systems with conical constraints and convex Lyapunov functions in the framework of convex processes

Linear control systems with conical constraints on controls and on states are modeled by set-valued mappings called convex processes. Asymptotic stability properties of convex processes are described by convex Lyapunov functions. Convex conjugacy of Lyapunov functions is used to show the relationship between asymptotic stability properties of a convex process and of its adjoint/dual process. Implications for asymptotic controllability of a linear system with conical control constraints and for detectability of a dual system are stated.
Studies of a U(1) × U(1) Yukawa model with staggered fermions☆

Abstract A U(1)×U(1) Yukawa model with staggered fermions is investigated in the broken phase. Spontaneous symmetry breaking on finite lattices is studied in two ways. In the first approach, which is similar to what is done in lattice QCD studies, we work with nonzero bare-fermion masses and try to extrapolate to the massless limit. In the second method, which to date has been the more common approach in Higgs-Yukawa models, we simulate directly the zero-bare-fermion-mass theory and carry out a global rotation on the fields before taking measurements. In the m f ≠0 calculations Ward identities are monitored to asses the quality of the simulations and both fermion-antifermion and purely bosonic operators are used in Goldstone boson correlation-functions. We point out differences between the fermion-antifermion channel in the current model and analogous calculations of the pion correlation-function in lattice QCD. We show that noisy estimates of the fundamental fermion propagator can also be used very effectively for meson correlations, where the fermion and antifermion annihilate into pure bosonic matter (the so called annihilation channel). Estimates for renormalized Yukawa and λφ 4 couplings obtained via the two methods, m f = 0 and m f ≠ 0, are also presented. Renormalized Yukawa-couplings are never much larger than the value obtained from the tree-level j = 0 partial wave unitarity bound for fermion-antifermion elastic scattering in a continuum theory with the appropriate number of flavors.
Chemical Vapor Deposition of Highly Transparent and Conductive Boron Doped Zinc Oxide Thin Films

Boron doped zinc oxide films have been successfully deposited from a gas mixture of 0.05% diethyl zinc, 2.3% ethanol and various diborane concentrations in the temperature range 300°C to 430°C in an atmospheric pressure chemical vapor deposition reactor. The dopant diborane was found to decrease the film growth rate. The crystallite sizes of doped films were smaller than those of undoped films. Hall coefficient and resistance measurements at room temperatures gave conductivities between 250 and 1700 Ω-1, electron densities between 1.4×1020 and 6.7×1020 cm-3, and mobilities between 7 and 23 cm2/V-s. Optical measurements showed that a film with a sheet resistance of 8.8 Ω/square has an average visible absorption of about 8% and maximum infrared reflectance close to 85%. The ratio of conductivity to absorption coefficient is between 0.05 Ω-1 and 0.55 Ω-1. The band gap of doped film was widened and followed the Burstein-Moss relation.
On loading rate effects in toughening processes

Environmental crack tip reactions are a known source of premature fracture in oxides. These rate-dependent phenomena commonly are studied in strength tests where loading rate serves as the major experimental variable. A material susceptible to environmentally-assisted crack growth is stronger at fast testing rates. A topic which has received far less attention is the influence of stressing rate or loading rate on the shielding processes which occur at some distance from the crack tip, although the inverse has been studied by Deuerler et al. In their work, the crack velocity-stress intensity, v-K, curve was measured as a function of crack length in alumina. The v-K curve shifted to higher stress intensities for longer cracks, indicative of greater shielding as the crack grew progressively up the K_R (resistance) curve. In this paper, we explore the influence of loading rate on the fracture toughness of two aluminum oxides, one which fails in a brittle fashion (i.e., where toughness is independent of crack length), and a second which demonstrates significant resistance curve behavior due to grain bridging behind the crack tip. We present here the first known documentation of a loading rate effect on shielding phenomena in ceramic materials.
Improving the Student Experience: Allowing Students Enrolled in a Required Course to Select Online or Face-to-Face Instruction

How does a marketing department, particularly one in a university with open admissions, best teach required undergraduate courses? Because "one size does not fit all," we suggest allowing students the option of completing those courses either online or face-to-face. Here, we describe parallel online and face-to-face versions of a marketing research course offered at a land grant university. Although course performance, as measured by grade distributions, did not differ by self-selected delivery method, overall retention rates and student satisfaction did improve. The adoption of this teaching innovation in other universities is strongly recommended.
Average-case analysis of VCG with approximate resource allocation algorithms

The Vickrey-Clarke-Groves (VCG) mechanism offers a general technique for resource allocation with payments, ensuring allocative efficiency while eliciting truthful information about preferences. However, VCG relies on exact computation of an optimal allocation of resources, a problem which is often computationally intractable, and VCG that uses an approximate allocation algorithm no longer guarantees truthful revelation of preferences. We present a series of results for computing or approximating an upper bound on agent incentives to misreport their preferences. Our first key result is an incentive bound that uses information about average (not worst-case) performance of an algorithm, which we illustrate using combinatorial auction data. Our second result offers a simple sampling technique for amplifying the difficulty of computing a utility-improving lie. An important consequence of our analysis is an argument that using state-of-the-art algorithms for solving combinatorial allocation problems essentially eliminates agent incentives to lie.
Determination of radiogenic helium in zircon by stable isotope dilution technique

Standard zircon samples studied earlier by Hurley, Larsen, and Gottfried (1955) have been analyzed for helium by an isotopic dilution technique using He3 as a spike yielding an accuracy of about ± 3 pct. The quantity of helium obtained is about 15 pct higher than that obtained by earlier volumetric techniques. Alpha activity determinations agree closely with earlier work. Measurements on non-metamict zircons from Ontario, Ceylon, and Oklahoma suggest that helium retentivity in excess of 80 pct is not unusual. Metamict zircons on the other hand may have retained only one per cent of radiogenic helium. Total irradiation is not the only factor in determining the quantity of helium retained. A helium age method is still possible under proper conditions.
GRB 990123: The Case for Saturated Comptonization

We find that the optical magnitudes of GRB 990123 observed by the Robotic Optical Transient Search Experiment move in tandem with the magnitudes extrapolated from the simultaneous BATSE spectra, strongly suggesting that the optical, X-ray, and gamma-ray photons originate from a single source. We then show that the broadband optical-gamma-ray spectra can be naturally fit by the saturated Compton model. We also derive the parameters of the Compton emitting shell from first principles.
COMPARISON OF CHEMICAL AND BIOLOGIC ASSAY OF CORTIN-LIKE SUBSTANCES IN NORMAL MALE URINE*

CHEMICAL analysis for the estimation of urinary “cortin” excretion in normal and abnormal subjects has been widely employed recently. The chemical methods have been based on oxidation of the a-ketol side chain at carbon 17 and the α, β-unsaturated 3-ketone grouping of ring A of the adrenal steroid nucleus (1, 2, 3, 4, 5). Both groups are essential for biologic cortin activity and chemically have a strong reducing action. The exact nature of the urinary material is not known although it has been assumed that it represents one or more of the known biologically active compounds which have been isolated from adrenal cortical extracts. This possibility has been further strengthened by the recent work of Mason et al. (6) who isolated 17-hydroxycorticosterone from the urine in a case of Cushing's syndrome associated with severe diabetes mellitus. Since the chemical methods of estimation of urinary cortin are sufficiently simple to be useful in routine clinical and research studies, it was considered advisable to...
Theory of Si/transition-metal silicide schottky barriers

Abstract The height of the Schottky barrier formed at transition-metal/Si interfaces varies over a very small range (≈0.4 eV) considering the wide range of electronic structures possible from one end of the transition-metal series to the other. Furthermore, the barriers are observed to form within a few monolayers of metal coverage, suggesting that the barrier is a property of the local bonding and that the true metallic states play only a minor role. A model has been developed to explain these facts in terms of the Fermi-level pinning mechanism of Schottky barrier formation. The physics contained in the model is that of a Si dangling bond sheltered from the transition-metal-silicide by an interfacial vacancy. Since (i) the dangling-bond is sheltered from the metallic-silicide and (ii) the atomic energy levels of the transition metal are out of resonance with Si, the dangling bond (which forms a level in the Si band gap) will be only weakly perturbed by the silicide. Thus this interfacial dangling bond can pin the Fermi level at nearly the same energy for all the transition-metal-silicides. A tight-binding calculation of the electronic structure of this defect at the NiSi2/Si(111) interface has been performed for an infinite interface using the transfer-matrix technique. The results of this calculation are described in terms of a very simple molecular model.
Effects of a Novel Inhibitor of Guanylyl Cyclase on Dilator Responses of Mouse Cerebral Arterioles

Background and Purpose Nitric oxide–induced vasodilatation is mediated by both cGMP-dependent and -independent mechanisms. Previous studies that examined the role of soluble guanylyl cyclase in cerebral vessels have used methylene blue and LY-83583, compounds that generate superoxide anion and are not specific for inhibition of soluble guanylyl cyclase. We examined the effects of ODQ (1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one), a novel and highly selective inhibitor of soluble guanylyl cyclase, on responses of cerebral arterioles. Methods The effects of ODQ on responses of cerebral arterioles to acetylcholine, nitroprusside, 8-bromo-cGMP, and adenosine were examined in anesthetized mice by means of a cranial window. The effects of two concentrations of ODQ were examined in the absence and presence of superoxide dismutase. The effects of NG-nitro-l-arginine, an inhibitor of nitric oxide synthase, were also tested. Results ODQ (3 and 10 μmol/L) produced concentration-dependent inhibition of dilatation of...
Quantitative analysis of artifacts in 4D DSA: the relative contributions of beam hardening and scatter to vessel dropout behind highly attenuating structures

When performing Computed Tomographic (CT) image reconstruction on digital subtraction angiography (DSA) projections, loss of vessel contrast has been observed behind highly attenuating anatomy, such as dental implants and large contrast filled aneurysms. Because this typically occurs only in a limited range of projection angles, the observed contrast time course can potentially be altered. In this work, we have developed a model for acquiring DSA projections that models both the polychromatic nature of the x-ray spectrum and the x-ray scattering interactions to investigate this problem. In our simulation framework, scatter and beam hardening contributions to vessel dropout can be analyzed separately. We constructed digital phantoms with large clearly defined regions containing iodine contrast, bone, soft issue, titanium (dental implants) or combinations of these materials. As the regions containing the materials were large and rectangular, when the phantoms were forward projected, the projections contained uniform regions of interest (ROI) and enabled accurate vessel dropout analysis. Two phantom models were used, one to model the case of a vessel behind a large contrast filled aneurysm and the other to model a vessel behind a dental implant. Cases in which both beam hardening and scatter were turned off, only scatter was turned on, only beam hardening was turned on, and both scatter and beam hardening were turned on, were simulated for both phantom models. The analysis of this data showed that the contrast degradation is primarily due to scatter. When analyzing the aneurysm case, 90.25% of the vessel contrast was lost in the polychromatic scatter image, however only 50.5% of the vessel contrast was lost in the beam hardening only image. When analyzing the teeth case, 44.2% of the vessel contrast was lost in the polychromatic scatter image and only 26.2% of the vessel contrast was lost in the beam hardening only image.
Lipoprotein lipase gene expression in THP-1 cells

Lipoprotein lipase (LPL) mRNA levels are under the control of signals that activate phospholipase C, resulting in activation of protein kinase C (PKC) and mobilization of intracellular Ca2+ in the human monocytic leukemia cell line THP-1. Induction of LPL in THP-1 cells appears to be mediated by PKC since it was affected by both phorbol 12-myristate 13-acetate (PMA) and a diacylglycerol analogue. This induction was blocked by the specific PKC inhibitor H-7. Although Ca2+ mobilization by the ionophore A23187 also induced LPL mRNA, the mechanism is most likely independent of activation of the Ca2+/calmodulin protein kinase. Depletion of cells of PKC made them refractory to induction by A23187, suggesting that Ca2+ mobilization acts by activating PKC. Addition of cycloheximide (CHX) to undifferentiated THP-1 cells resulted in a transient increase in steady-state mRNA levels (3-fold). Sustained superinduction of LPL mRNA occurred when PMA and CHX were added simultaneously. These results suggest that the level of LPL mRNA is regulated either by a labile regulatory protein, which represses transcription of the LPL gene, or by a protein affecting mRNA stability.
Premature induction of hepatic tryptophan oxygenase.

Subcutaneous administration of hydrocortisone acetate to the newborn rat produces a premature induction of hepatic tryptophan oxygenase consisting of a transient rise in activity 6–8 h after treatment, followed by a second sustained rise beginning 40 h later, which plateaus at 10 days of age. Cycloheximide treatment at the midpoint of this second elevation inhibits protein synthesis, but not tryptophan oxygenase activity. In older animals, cycloheximide treatment does both. Tryptophan administration at this midpoint rapidly elevates tryptophan oxygenase activity. This elevation can be partially blocked by treatment with actinomycin D within 1 h of tryptophan administration, but not thereafter. Actinomycin treatment is ineffective in blocking the tryptophan-induced rise in older animals. Administration of hydrocortisone acetate to 5- and 10-day-old pups leads to a more rapid and sustained rise in tryptophan oxygenase activity without appearance of a transient induction phase. Neither tryptophan alone, δ-aminolevulinic acid alone, nor tryptophan plus δ-aminolevulinic acid prematurely induces tryptophan oxygenase in newborn or 5-day-old rats.
Integrating tester pin electronics

A 10-V pin electronics driver that can output signals with low distortion and fast risetimes for both narrow and wide voltage swings is described. The features combine to eliminate the need for dual drivers, pin cards, or test heads, which simplifies the testing of mixed-technology devices or modules. A high-voltages process module has been added to a standard 1.5- mu m digital CMOS process, which allows the driver to be in the same silicon as the timing and formatting circuitry. Design and calibration techniques that overcome the limitations of the high-voltage CMOS process are examined. >
MPI-IO/GPFS, an Optimized Implementation of MPI-IO on Top of GPFS

MPI-IO/GPFS is an optimized prototype implementation of the I/O chapter of the Message Passing Interface (MPI) 2 standard. It uses the IBM General Parallel File System (GPFS) Release 3 as the underlying file system. This paper describes optimization features of the prototype that take advantage of new GPFS programming interfaces. It also details how collective data access operations have been optimized by minimizing the number of messages exchanged in sparse accesses and by increasing the overlap of communication with file access. Experimental results show a performance gain. A study of the impact of varying the number of tasks running on the same node is also presented.
Direct Observation of Microwaves Excited in the Fermilab Beam Pipe by Very Narrow Bunches

The bunch rotation exchange of time for momentum spread in the Fermilab Antiproton Source is dependent upon proton bunch narrowing at 120 GeV in the Main Accelerator. The original procedure proposed to accomplish bunch narrowing involved adiabatic reduction of the Main Ring rf voltage (and bucket height) until the bunches span approximately + or -..pi../2 radians in the bucket, followed by a sudden increase in rf voltage causing bunch rotation within the now mismatched bucket and consequent bunch narrowing in time spread. This procedure suffers from several draw-backs. One fundamental problem is that during the adiabatic portion of the procedure the bunches are caused to have a very low momentum spread and to remain in this condition for many phase oscillation periods. In this circumstance the bunches may be subject to microwave instability which would limit the momentum spread reduction and consequently the final bunch length. A second problem with the procedure is simply that it requires an inordinately long time and may at some point limit the cycle time and consequently the antiproton production rate. Thirdly, since antiprotons are produced by a single batch of 83 bunches occupying only 1/13 of the 1113 Main Ring buckets, the beam qualitymore » during the long counterphasing period may suffer from imprecise compensation for transient beam loading of the rf system. When the voltage has been reduced to the very low value required to match the elongated bunch configuration, about 4 kappaV, the beam induced voltage may be comparable to that required to create the buckets, compensation notwithstanding.« less
Particle acceleration at perpendicular shock waves: Model and observations

Received 7 November 2005; revised 17 February 2006; accepted 27 February 2006; published 23 June 2006. [1] On the basis of a recently developed nonlinear guiding center theory for the perpendicular spatial diffusion coefficient k? used to describe the transport of energetic particles, we construct a model for diffusive particle acceleration at highly perpendicular shocks, i.e., shocks whose upstream magnetic field is almost orthogonal to the shock normal. We use k? to investigate energetic particle anisotropy and injection energy at shocks of all obliquities, finding that at 1 AU, for example, parallel and perpendicular shocks can inject protons with equal facility. It is only at highly perpendicular shocks that very high injection energies are necessary. Similar results hold for the termination shock. Furthermore, the inclusion of self-consistent wave excitation at quasiparallel shocks in evaluating the particle acceleration timescale ensures that it is significantly smaller than that for highly perpendicular shocks at low to intermediate energies and comparable at high energies. Thus higher proton energies are achieved at quasiparallel rather than highly perpendicular interplanetary shocks within 1 AU. However, both injection energy and the acceleration timescale at highly perpendicular shocks are sensitive to assumptions about the ratio of the two-dimensional (2-D) correlation length scale to the slab correlation length scale l2D/lk. Model proton spectra and intensity profiles accelerated by a highly perpendicular interplanetary shock are compared to an identical but parallel interplanetary shock, revealing important distinctions. Finally, we present observations of highly perpendicular interplanetary shocks that show that the absence of upstream wave activity does not inhibit particle acceleration at a perpendicular shock. The accelerated particle distributions closely resemble those expected of diffusive shock acceleration, and observed at oblique shocks, an example of which is shown.
Moments of order statistics of the Cantor distribution

Abstract We obtain recursive formulas for the expected values of order statistics from the Cantor distribution defined by Lad and Taylor (Statist. Probab. Lett. 13 (1992) 307–310), and for a skew generalization of it. The formulas are used to calculate the L-moments of the distribution.
The efficacy of a restart break for recycling with optimal performance depends critically on circadian timing.

Objectives Under simulated shift-work conditions, we investigated the efficacy of a restart break for maintaining neurobehavioral functioning across consecutive duty cycles, as a function of the circadian timing of the duty periods. Design As part of a 14-day experiment, subjects underwent two cycles of five simulated daytime or nighttime duty days, separated by a 34-hour restart break. Cognitive functioning and high-fidelity driving simulator performance were tested 4 times per day during the two duty cycles. Lapses on a psychomotor vigilance test (PVT) served as the primary outcome variable. Selected sleep periods were recorded polysomnographically. Setting The experiment was conducted under standardized, controlled laboratory conditions with continuous monitoring. Participants Twenty-seven healthy adults (13 men, 14 women; aged 22-39 years) participated in the study. Interventions Subjects were randomly assigned to a nighttime duty (experimental) condition or a daytime duty (control) condition. The efficacy of the 34-hour restart break for maintaining neurobehavioral functioning from the pre-restart duty cycle to the post-restart duty cycle was compared between these two conditions. Results Relative to the daytime duty condition, the nighttime duty condition was associated with reduced amounts of sleep, whereas sleep latencies were shortened and slow-wave sleep appeared to be conserved. Neurobehavioral performance measures ranging from lapses of attention on the PVT to calculated fuel consumption on the driving simulators remained optimal across time of day in the daytime duty schedule, but degraded across time of night in the nighttime duty schedule. The 34-hour restart break was efficacious for maintaining PVT performance and other objective neurobehavioral functioning profiles from one duty cycle to the next in the daytime duty condition, but not in the nighttime duty condition. Subjective sleepiness did not reliably track objective neurobehavioral deficits. Conclusions The 34-hour restart break was adequate for maintaining performance in the case of optimal circadian placement of sleep and duty periods (control condition) but was inadequate (and perhaps even detrimental) for maintaining performance in a simulated nighttime duty schedule (experimental condition). Current US transportation hours-of-service regulations mandate time off duty but do not consider the circadian aspects of shift scheduling. Reinforcing a recent trend of applying sleep science to inform policymaking for duty and rest times, our findings indicate that restart provisions in hours-of-service regulations could be improved by taking the circadian timing of the duty schedules into account.
Characterization of spatial and spectral resolution of a rotating prism chromotomographic hyperspectral imager

The Air Force Institute of Technology (AFIT) has built a rotating prism chromotomographic hyperspectral imager (CTI) with the goal of extending the technology to exploit spatially extended sources with quickly varying (> 10 Hz) phenomenology, such as bomb detonations and muzzle flashes. This technology collects successive frames of 2-D data dispersed at different angles multiplexing spatial and spectral information which can then be used to reconstruct any arbitrary spectral plane(s). In this paper, the design of the AFIT instrument is described and then tested against a spectral target with near point source spatial characteristics to measure spectral and spatial resolution. It will be shown that, in theory, the spectral and spatial resolution in the 3-D spectral image cube is the nearly the same as a simple prism spectrograph with the same design. However, error in the knowledge of the prism linear dispersion at the detector array as a function of wavelength and projection angle will degrade resolution without further corrections. With minimal correction for error and use of a simple shift-and-add reconstruction algorithm, the CTI is able to produce a spatial resolution of about 2 mm in the object plane (234 μrad IFOV) and is limited by chromatic aberration. A spectral resolution of less than 1nm at shorter wavelengths is shown, limited primarily by prism dispersion.