cssi/SciSciGPT-SciSciNet huggingface dataset:
Applications of ultra-high solar flux

Abstract Nonimaging optics provides a means of concentrating light to intensities approaching the theoretical limit. In experiments at the University of Chicago, we measured a concentration of 84,000 using a sapphire concentrator. We are currently scaling up our experiments at the National Renewable Energy Laboratory in Golden, Colorado. Our goals include a) measuring 50,000 suns using a borosilicate concentrator with total power collected approaching one kW, b) producing fullerenes by vaporizing carbon, and c) pumping solid state lasers using a side-pumping arrangement. Preliminary results indicate that we have delivered 50,000 suns through an aperture using a concentrator of unique design. In this paper, we report on this measurement and current designs for fullerene production and laser pumping.
Dynamic Simulation of a Kanban Production Inventory System

The implementation of the Japanese inventory control system, Kanban, in a production line, reduces Work‐in‐Process (WIP) inventory without affecting production or sales, though there is a point at which the reverse becomes true. The hypothesis that Kanban policy would reduce total WIP inventory without affecting production/sales at all was tested under two environmental conditions, cyclical demand and constant growth demand, by means of a simulated model, and also showed that under cyclical demand, frequent starts and stops in the line due to use of all the Kanban cards will produce eventual growth in all inventories, if not rectified. It is hoped that further research will develop a sufficently comprehensive model to facilitate the implementation of such a materials handling system.
The Spectral Statistics of Triangular Quantum Billiards

We study the spectral statistics of three triangular quantum billiards. We show that for an ergodic billiard the nearest neighbor spacings distribution in the low energy regime is strongly influenced by a neighboring integrable domain (equilateral triangle). With increasing energy we observe a transition towards a more chaotic-like pattern. We also show that for all three triangles the properties of the spectral distributions depend heavily on the energy range considered. This is specially true for the spectral rigidity, because of its essentially local character. The features of the distributions do not depend strongly on the genus of classical billiards.
Multiple reoperations in recurrent colorectal carcinoma. An analysis of morbidity, mortality, and survival

Fifty-eight patients in an existing prospective study were evaluated to determine if multiple reoperations for recurrent colorectal carcinoma extended survival. All patients had at least three major operative procedures. The median survival from first, second, third, fourth, and fifth recurrence was 29.9, 17.3, 16, 12.3, and 7.2 months, respectively. The median postoperative hospital stay was 11 days, with a range of 1 to 96 days. The major complication rate was 17%. Twenty-one patients are still alive 19 to 140 months from diagnosis (mean, 50.3 months), 9 to 125 months from the first recurrence (mean, 31.1 months), and 5 to 109 months (mean, 22 months) from the second recurrence. Eleven patients have no evidence of disease. Reoperation for recurrent colorectal carcinoma can be done with acceptable morbidity and mortality and an increase in survival.
Interfacial stability and mechanical property of TiC/Mg composites produced by in situ combustion synthesis

AbstractInterfacial stability of TiC/Mg metal matrix composites (MMCs) produced by in situ combustion synthesis of Al–Ti–C reaction system in molten Mg has been studied in terms of its microstructure, composite density and mechanical properties. Mg and cubic TiC phases were detected through X-ray diffraction and energy dispersive spectroscopy (EDS) analysis, which indicate that the Al–Ti–C reaction system has converted to the TiC phase through a combustion reaction. Microstructural analysis showed the uniform distribution of 1 μm sized spherical TiC within the Mg matrix. In situ produced TiC/Mg MMCs had the formation of an Al layer on the TiC surface. The oxygen contents at the matrix, interface and reinforcement were detected at <1.5 at-% by TEM-EDS analysis. However, the oxygen content of ex situ composites at the interface was 6.5 at-%. An average relative density of the in situ produced composites was 96%, while the ex situ composites, by comparison, were <94%. The ultimate compressive strength and th...
Tetrakisdimethylamidozirconium and its dimethylamido lithium adduct: Structures of [zr(nme2)4]2 and zr(nme2)6li2(thf)2

Abstract The molecular structure of [Zr(NMe2)4]2 has been determined by an x-ray study and shown to involve a central Zr2N8 moiety involving the fusing of two trigonal bipyramidal units along a common axial-equatorial edge. The terminal ZrNMe2 units have trigonal planar coordination about the nitrogen atoms: ZrN = 2.050(5) and 2.104(5) A, and ZrN (bridge) = 2.224(3) and 2.453(4) A for equatorial and axial bonds, respectively. The ZrZr distance is 3.704(1) A as expected for a non-MM bonding bridged compound. In tetrahydrofuran solution, Zr(NMe2)4 and LiNMe2 react irreversibly giving Zr(NMe2)6 Li2(THF)2 which has been isolated and characterized by an X-ray study. The central ZrN6 octahedral moiety is capped on two opposite faces by Li atoms which are also coordinated to an oxygen atom of a THF molecule. Pertinent distances are: ZrN = 2.22(7) (av.), NLi = 2.155(25) (av.) and LiO = 1.915(10) A.
Dynamical charge susceptibility of the spinless Falicov-Kimball model

An exact solution is presented for the frequency-dependent charge susceptibility of the spinless Falicov-Kimball model by using dynamical mean-field theory. We develop a nontrivial application of the Baym-Kadanoff ``conserving approximation'' formalism to exactly determine the frequency-dependent vertex function (which turns out to assume a particularly simple form). We show how the static and dynamic susceptibilities are decoupled in this model and how the dynamic susceptibility generically does not show any signal of the low-temperature charge-density-wave phase transition. We also examine the temperature evolution of the dynamic charge susceptibility for the special case of half-filling.
A High Power Inductively Coupled Plasma Torch and Impedance Matching Network

The relative ease of operation, power handling capabilities, and overall performance of an inductively coupled plasma-optical emission spectrometer depends upon numerous factors, not the least important of which is the design of the torch. A variety of such designs has appeared in the literature. Most workers have employed three concentric fused silica and/or Pyrex tubes, referred to as an inner sample gas tube, a "flaired mouth" plasma gas tube, and an outer coolant tube. These tubes are either fused into one- or two-piece units through glass blowing techniques or mounted in some type of dismantleable base assembly.
Modulation of thymosin β4 by estrogen

Abstract The endocrine thymus produces several hormone-like peptides (generically termed thymosins) which control development of the thymic-dependent lymphoid system and participate in the process of immune regulation. In addition, recent literature supports the hypothesis that gonadal steroids in general and estrogens in particular affect the immune system. To determine whether steroid hormones modulate secretion of thymic peptides, basal concentrations of thymosins α 1 and β 4 were determined by radioimmunoassay in morning blood samples from 87 women in various clinical states. Basal concentrations of thymosin α 1 were similar in all women sampled. Basal levels of thymosin β 4 were similar in normal women during the early follicular phase, women with premature ovarian failure, postmenopausal women not receiving estrogen, and individuals with gonadal dysgenesis. However, the marked variability of basal levels in premature ovarian failure and in postmenopausal women suggests that these groups are quite heterogeneous. Thymosin β 4 concentrations were reduced in castrated women not receiving estrogen and were decreased more in both postmenopausal women and castrated women who were on chronic estrogen therapy. These data suggest that estrogens can modulate the circulating levels of thymosin β 4 but not of thymosin α 1 . We do not yet know whether sex steroids modulate secretion of other thymic peptides.
Remarks on thermal strings outside black hole

Abstract We discuss the semiclassical approximation to the level density of (super) strings propagating in non-compact coset manifolds G H . We show that the WKB ansatz agrees with heuristic red-shift arguments with respect to the “exact” sigma-model metric, up to some deviations from minimal coupling, parametrized by the dilaton. This approximation is used to study thermal ensembles of free strings in black holes, with the “brick wall” horizon regularization of 't Hooft. In two dimensions the entropy diverges logarithmically with the horizon thickness, and a local Hagedorn transition occurs in higher dimensional models. We also observe that suppersymmetry improves the regularity of strings art the horizon
No relief: Tax prices and property tax burdens ☆

Abstract In 2001 the state of Minnesota reduced the weights assigned to non-residential property in local property tax bases, which increased residents' price of raising property tax revenue and affords the opportunity to identify the tax price elasticity of local tax revenues and expenditures. Results suggest that a one percent increase in residents' tax prices is associated with a one percent decrease in per-resident property tax revenues as well as a substantial reduction in capital expenditures. The unit price elasticity of property tax revenues suggests that popular tax relief programs that reduce residents' tax prices – homestead exemptions – do not reduce homeowners' tax payments.
Potential energy constants, rotational distortion constants, and calculated thermodynamic properties for methyl cyanide and methyl isocyanide

Abstract A normal coordinate analysis of methyl cyanide (CH 3 CN) and methyl isocyanide (CH 3 NC) has been made, following Wilson's FG matrix method. The potential energy constants thus obtained were then used in the evaluation of the rotational distortion constants. Molar thermodynamic properties—heat, content, free energy, entropy, and heat capacity—for the ideal gaseous state at one atmosphere pressure, and with the usual rigid-rotor harmonic-oscillator approximation, also have been calculated for 12 temperatures from 100 to 1000°K.
Conflict and transition in adolescent moral development.

TURIEL, ELLIOT. Conflict and Transition in Adolescent Moral Development. CHILD DEVELOPMENT, 1974, 45, 14-29. The process of moving from stage to stage has not been systematically examined in developmental theories. As a consequence, responses reflecting progressive development have been inaccurately categorized as reflecting regressive behavior. The theoretical relations between regression and progression in developmental-stage theories are discussed. A detailed analysis of stage transition in adolescent moral judgments is presented. It is hypothesized that transition from one stage to the next involves a phase of conflict or disequilibrium, during which the existing mode of thinking is reevaluated and a new mode is constructed.
Cell lines from culicoides variipennis diptera ceratopogonidae support replication of bluetongue virus

Cell lines have been developed from 2-day-old embryos of the biting midge, Culicoides variipennis (Diptera: Ceratopogonidae). In North America C. variipennis is the primary insect vector of bluetongue virus (BTV), an orbivirus that causes disease of ruminants. The C. variipennis (CuVa) cells, grown in Schneider's Drosophila medium, consist primarily of a fibroblast-like cell type. CuVa cells are very hardy. They can grow over a wide range of temperature and pH and adapt to growth in minimal essential medium. BTV replicates to high titer (7.5-8.0 log10 50% tissue culture infectious doses/ml) in CuVa cells over a wide range of temperatures (19 degrees to 37 degrees C) without inducing any significant cytopathic effects. The highest BTV titers were obtained in CuVa cells grown at 25 degrees and 32 degrees C. Cells from C. variipennis can be useful for many diverse investigations.
Uptake of dissolved Ag, Cd, and Co by the clam, Macoma balthica: relative importance of overlying water, oxic pore water, and burrow water.

The facultative deposit-feeding clam Macoma balthica is used as a bioindicator organism for assessing coastal metal contamination. Previous work has evaluated the assimilation of metals from different possible food sources for this clam, but no studies have measured the uptake rates of metals from different dissolved sources. This study specifically compares three different dissolved sources: overlying water (SW), oxic pore water (OPW) from a depth of <1 cm (entrained during surface deposit feeding), and burrow water (BW) (a mixture of anoxic pore water and overlying water). Uptake rates of dissolved Ag, Cd, and Co in M. balthica were measured in short-term laboratory experiments using radiotracers. Clams were exposed to metals in water only for SW and surface OPW treatments. In the BW treatment, metal uptake was compared in clams placed in radiolabeled organic-poor or organic-rich sediment under conditions in which feeding was inhibited. Uptake rate constants from SW for Ag, Cd, and Co were 0.35, 0.033,...
Normal and unusual transient events in IRAC images

The Spitzer Space Telescope Infrared Array Camera (IRAC) is a four-channel camera that uses two pairs of 256 x 256 pixel InSb and Si:As IBC detectors to provide simultaneous images at 3.6, 4.5, 5.8, and 8 microns. IRAC experiences a flux of cosmic rays that produce transient events in images from each of the arrays, with 5-7 pixels per second being affected in an IRAC integration. The vast majority of these transient events can be adequately characterized so they can be effectively detected and flagged by a pipeline software module. However, because of the nature of the arrays and their arrangement in the camera structure, a small fraction of the cosmic ray hits on IRAC produce transients with unusual morphologies which cannot be characterized in a general way. We present nominal cosmic ray rates observed for IRAC on-orbit and rates observed during a period of elevated solar proton flux following a series of X-class solar flares in late 2003. We also present a guide for observers to help identify unusual transient events in their data. We comment on the physical nature of the production of many o9f these unusual transients and how this mechanism differs from the production of "normal" transient events.
Atypical complications of gastric bypass surgery

Although gastric bypass surgery continues to grow in popularity for weight loss and weight maintenance in the morbidly obese, there has been little attention given to the imaging of complications associated with these surgeries. The purpose of our study is to demonstrate the variety of gastric bypass surgery complications that can be identified radiographically, with attention to the more unusual complications. This study was performed with institutional Internal Review Board approval. We performed a 5-year retrospective review of all patients who had undergone gastric bypass surgery, had complications of the surgery, and had studies performed in our department to image these complications. These studies consisted of contrast fluoroscopy and CT. We identified the more common complications of anastomotic stenoses and anastomotic leaks. We also identified six unusual complications as follow: (1) internal herniation through the small bowel mesentery, (2) internal herniation through the transverse mesocolon, (3) external herniation through the abdominal wall incision, (4) enterocutaneous fistulas, (5) antiperistaltic construction of the Roux-en-Y, and (6) incorrect anstomoses of the Roux limbs resulting in a Roux-en-O configuration. Our findings show that a thorough understanding of expected postoperative bowel configuration is essential in the evaluation of these patients. In addition, fluoroscopic evaluation should assess not only anatomy, but also motility.
Understanding the diversity of foliar endophytic fungi: progress, challenges, and frontiers

Abstract Fungal endophytes, a diverse group of primarily ascomycetous fungi defined functionally by their occurrence within asymptomatic photosynthetic tissues of plants, occur in all major lineages of land plants and in natural and anthropogenic communities ranging from the arctic to the tropics. Because of the tremendous diversity they encompass, ecological questions regarding the interactions of endophytes with the plants in which they live - and with other organisms that in turn interact with endophyte-plants symbiota – are difficalt to address. The goals of this review are to highlight progress, challenges, and frontiers in the study of foliar endophyte diversity, with the ultimate goal of encouraging research that both bridges the gap between, and advances, research in alpha taxonomy and ecology. I focus on four themes that are reflected in the recent and rapidly expanding literature regarding endophyte biology: (1) the taxonomic and ecological distinctiveness of endophytes relative to other nonpathogenic plant-associated fungi; (2) the insights that can be gained from studies that consider genotypes as the relevant unit of biological organization, especially in the context of traditional species-level taxonomy and robust phylogenetic methods that tie these genotypes and species together in an explicit evolutionary context; (3) the context-dependency of endophyte communities, highlighting the importance of both the identify of host plants and the geographic location in which plants occur; and (4) the complexity of the endophyte-pathogen-saprotroph continuum, and the challeges and exciting frontiers that lie in understanding the evolutionary relationships and ecological lability of fungi that exhibit these ecological modes. I argue that never before has the study of endophytic fungi been more exciting or more tractable, and that the potential for endophyte researchers to inform diverse areas of biology has never been greater.
Iron absorption in patients with Zollinger–Ellison syndrome treated with long-term gastric acid antisecretory therapy

Background: Gastric acid secretion is important for absorption of dietary non-haem iron, and iron deficiency is common in gastric hyposecretory states such as after gastric resection. It is not known if prolonged, continuous treatment with potent acid suppressants such as omeprazole will lead to iron deficiency or lower body iron stores. Aim: To assess iron stores and the occurrence of iron deficiency anaemia in patients with Zollinger–Ellison syndrome (ZES) treated long-term with gastric antisecretory drugs. Methods: One hundred and nine patients with ZES but without previous gastric resections were studied. All patients underwent assessment of acid control on antisecretory agents, determination of tumour extent, evaluation of haematological parameters (Hct, haemoglobin, WBC, MCV, MCHC), and determination of serum iron parameters (iron, ferritin, transferrin, iron/transferrin ratio). Acid control values for the last 4 years were reviewed, the presence or absence of acid hyposecretion determined using three different criteria and this result correlated with haematological and iron parameters. Results: Eighty-nine patients were taking omeprazole, nine patients were taking histamine H2-antagonists and 11 patients were taking no drugs following curative resection. The mean duration of omeprazole treatment was 5.7 years (range 0.7–12.5 years) and total duration of any treatment was 10.1 years (range 0.7–21 years). Acid hyposecretion was present by at least one criterion in 45% of patients. There were no significant differences between patients with or without acid hyposecretion, taking or not taking omeprazole, having different durations of omeprazole treatment or different durations of total time receiving any antisecretory treatment, for any serum iron parameter, haematological parameter, or for the frequency of iron deficiency. Males and females did not differ in percentage with low ferritin levels or percentage with iron deficiency. Conclusions: Continuous treatment with omeprazole for 6 years or continuous treatment with any gastric antisecretory drug for 10 years does not cause decreased body iron stores or iron deficiency. These results suggest that, in contrast to recent results which show yearly monitoring of vitamin B12 in such patients is needed, such monitoring for iron parameters is not necessary.
Initial apoptosis is followed by increased proliferation of apoptosis-resistant endothelial cells

We have demonstrated that VEGF receptor blockade in combination with chronic hypoxia causes in rats severe angioproliferative pulmonary hypertension (SAPH) associated with arterial occlusion by proliferating endothelial cells, and we postulate that the established, lumen-occluding lesions are the result of the emergence of apoptosis-resistant proliferating cells. To study the dependence of exuberant endothelial cell proliferation on initial apoptosis, we adapted the CELLMAX artificial capillary system to analyze the effects of a VEGF receptor antagonist (SU5416) on human pulmonary microvascular endothelial cells under pulsatile shear stress. Immunohistochemical staining for caspase-3 and PCNA and flow cytometry for Annexin-V and BrdU supported our concept, since SU5416 caused initial apoptosis (35.8% at 24 h after the SU5416 addition and 4.8% in control cells) whereas the surviving cells became hyperproliferative (PCNA positive). Flow cytometry showed that apoptosis inhibition prevented the proliferation following the initial apoptosis. These lumen-filling endothelial cells were apoptosis resistant, grew without serum, and were phenotypically altered in that they express the tumor marker survivin. Hyperproliferative apoptosis-resistant cells were also generated by adding apoptosed cells instead of the VEGF receptor blocker to the CELLMAX system. In conclusion, endothelial cell death resulted in the selection of an apoptosis-resistant, proliferating phenotypically altered endothelial cell phenotype.
Human immunodeficiency virus type 1 Vpr arrests the cell cycle in G2 by inhibiting the activation of p34cdc2-cyclin B.

Human immunodeficiency virus type 1 (HIV-1) vpr inhibits the replication of tumor cell lines and peripheral blood mononuclear cells. Here it is demonstrated that expression of vpr, either in the context of a provirus or from an independent genetic element, induces a discrete cell cycle arrest, with cells containing 4N DNA. Low cyclin B-associated kinase activity, as well as the status of p34cdc2 and cdc25C phosphorylation, indicates that the cascade of reactions which drives the cell into mitosis has not been initiated. The phosphatase inhibitor okadaic acid releases the block, suggesting that Vpr perturbs upstream regulatorsof the G2-M transition. These studies demonstrate that HIV-1 vpr has profound effects on the cellular factors which control entry into mitosis and indicate vpr9s potential contribution to the cellular pathology associated with HIV-1 infection.
Importance of CHARM in relation to other heart failure trials with ARBs

Angiotensin-converting-enzyme (ACE) inhibitors, b-blockers, and spironolactone (for patients with severe heart failure) have substantially improved survival in chronic heart failure. Because angiotensin-receptor blockers (ARBs) provide specific and potent inhibition of the angiotensin type-1 receptor, there has been hope that they might extend the benefits of ACE inhibitors. ELITE-II found no benefit with losartan 50 mg a day compared with captopril. In retrospect, losartan may have been less effective than other ARBs or under-dosed. In Val-HeFT, valsartan 160 mg twice daily was beneficial in a population where 93% were on an ACE inhibitor, although subgroup analysis led to speculation that this benefit was largely restricted to patients not on ACE inhibitors and that addition of valsartan may have been harmful in patients treated with both ACE inhibitors and b-blockers. However, no such safety concern with valsartan plus b-blockers was found in the subsequent VALIANT trial. CHARM directly addressed the major questions raised by Val-HeFT. In CHARM, candesartan titrated to 32 mg a day reduced mortality and morbidity both in patients who were receiving ACE inhibitors and in those intolerant to ACE inhibitors. There was also substantial benefit in adding candesartan to the combination of ACE inhibitors and b-blockers. Among patients with low ejection fraction, candesartan resulted in highly significant reductions in cardiovascular death and heart-failure hospitalization, and in all-cause mortality. Thus, in patients with low ejection fraction, candesartan improves survival, regardless of background therapy. Candesartan should now be considered as another important treatment to further improve outcome in patients with chronic heart failure.
Dünnfilm‐Elektrolumineszenz‐Bildschirme

Verdrangen neuartige flache TFEL-Bildschirme die klassischen Kathodenstrahlrohren? Man erwartet mechanisch stabile, temperaturunempfindliche, langlebige und kontrastreiche Displays. Farbige TFEL-Schirme sind in der Entwicklung.
Absolute Thermoelectric Power and Electrical Resistivity of Chromium-Rich Chromium-Nickel Alloys

The absolute thermoelectric power S and resistivity ϱ of chromium-nickel alloys with up to 10 at% nickel were measured between 100 and 600 °K. Both ϱ and S were linear functions of the temperature above room temperature. Alloys with less than 4 at% nickel showed at lower temperatures a maximum in ϱ and S, which was attributed to antiferromagnetic ordering. The Neel temperature decreases about 100 °K/at% Ni. Die absolute Thermokraft S und der elektrische Widerstand ϱ in Chrom-Nickel-Legierungen mit Nickelkonzentrationen bis zu 10 At% wurde zwischen 100 und 600 °K bestimmt. Sowohl S als auch ϱ sind oberhalb Zimmertemperatur lineare Funktionen der Temperatur. Legierungen mit weniger als 4 At% Nickel zeigen bei tieferen Temperaturen ein Maximum in S und ϱ, welches mit antiferromagnetischen Ordnungsvorgangen in Zusammenhang gebracht wurde. Die Neeltemperatur sinkt etwa um 100 °K/At% Ni.
Preliminary investigation of movement time between brake and accelerator pedals in automobiles

This report represents the results of a preliminary study to determine if there is a valid cause to question the positional relationship of brake and accelerator pedals in contemporary automobiles....
Some aspects of macrophage behavior at the implant interface

The macrophage plays a pivotal role in both wound healing and cellular response to implants, including percutaneous devices. Within twenty-four hours macrophages were found in close contact with the implant surface. Eventually fibroplasts and connective tissue proliferate, and finally the implant will be encapsulated. The presence of macrophages is essential for the activation of collagen synthesis by fibroplasts . Implant shape and surface can profoundly affect macrophage behavior. At rough implant surfaces macrophages with giant cells are present for many months with the possibility of chronic granulomatous reactions. Superior tissue compatibility should be associated with smooth, well contoured implants with no acute angles.
Genetic and Environmental Influences on Cognition Across Development and Context

Genes account for between approximately 50% and 70% of the variation in cognition at the population level. However, population-level estimates of heritability potentially mask marked subgroup differences. We review the body of empirical evidence indicating that (a) genetic influences on cognition increase from infancy to adulthood, and (b) genetic influences on cognition are maximized in more advantaged socioeconomic contexts (i.e., a Gene × Socioeconomic Status interaction). We discuss potential mechanisms underlying these effects, particularly transactional models of cognitive development. Transactional models predict that people in high-opportunity contexts actively evoke and select positive learning experiences on the basis of their genetic predispositions; these learning experiences, in turn, reciprocally influence cognition. The net result of this transactional process is increasing genetic influence with increasing age and increasing environmental opportunity.
Why Presence Occurs: Evolutionary Psychology, Media Equation, and Presence

Despite the intense interest in the phenomena of presence, there have been limited attempts to explain the fundamental reason why human beings can feel presence when they use media and/or simulation technologies. This is mainly because previous studies on presence have focused on “what” questions---what are the causes and effects of presence?---rather than the “why” question. The current paper tries to solve this problem by providing an elaborated---and probably controversial---account of the fundamental presence-enabling mechanism. More specifically, it explains the modularity of human minds, and proposes that human beings can feel presence due to the automatic application of two types of causal reasoning modules---folk-physics modules for knowing about physical causation, and folk-psychology modules for knowing about social causation---when they respond to mediated and/or simulated objects. Finally, it explains the media-equation phenomena (in which media or computer users feel physical or social presence) according to the modularity argument.
Organizational Culture and the Performance of Critical Infrastructure: Modeling and Simulation in Socio-Technological Systems

Civil infrastructures are vital elements of a nation's physical well-being and quality of life because modern economies rely on the services these systems provide to move goods, people, and information safely and reliably. The linkage between systems and services is critical because the institutions and people that manage, operate, and maintain them are as important as the physical assets. This paper will examine several catastrophic system failures of the past twenty years from the perspective of the role played by the organization itself in facilitating disaster. It will seek to demonstrate that organizational culture and values, and their effect on individual members of the organization, are critical to safe and reliable systems. It will also suggest that simulations, employing agent-based models and other tools from the social sciences, would be useful in enhancing our understanding of the complex interactions that occur in these socio-technological systems.
Interventional loopless antenna at 7 T.

The loopless antenna MRI detector is comprised of a tuned coaxial cable with an extended central conductor that can be fabricated at sub-millimeter diameters for inteventional use in guidewires, catheters or needles. Prior work up to 4.7T suggests a near-quadratic gain in signal-to-noise ratio (SNR) with field strength, and safe operation at 3T. Here for the first time, the SNR performance and RF safety of the loopless antenna is investigated both theoretically, using the electro-magnetic method-of-moments, and experimentally in a standard 7T human scanner. The results are compared with equivalent 3T devices. An absolute SNR gain of 5.7±1.5-fold was realized at 7T vs. 3T: more than 20-fold higher than at 1.5T. The effective field-of-view (FOV) area also increased approximately 10-fold compared to 3T. Testing in a saline gel phantom suggested safe operation is possible with maximum local 1-g average specific absorption rates of <12W/kg and temperature increases of <1.9°C, normalized to a 4W/kg RF field exposure at 7T. The antenna did not affect the power applied to the scanner's transmit coil. The SNR gain enabled MRI microscopy at 40-50μm resolution in diseased human arterial specimens, offering the potential of high-resolution large-FOV or endoscopic MRI for targeted intervention in focal disease.
Synthesis of a Novel Volatile Platinum Complex for Use in CVD and a Study of the Mechanism of Its Thermal Decomposition in Solution

The synthesis, characterization, chemical vapor deposition, and mechanistic investigation of the thermal decomposition in aromatic solvents of cis-bis(η2,η1-pent-4-en-1-yl)platinum (1) are described. Complex 1 has a unique chelated structure, giving rise to enhanced volatility, and has proved useful for the chemical vapor deposition of thin platinum films under mild conditions. Films deposited on a glass slide in a hot walled glass tube at 175 °C have an elemental composition of 82% Pt and 18% C. Kinetic, deuterium labeling, and chemical trapping experiments indicate that the decomposition of 1 in aromatic solvents proceeds by reversible β-hydride elimination followed by reversible dissociation of 1,4-pentadiene to give a 3-coordinate platinum hydride intermediate (9). Reductive elimination of 1-pentene from 9 deposits metallic platinum. The rate of decomposition exhibits a significant β-deuterium isotope effect of kH/kD = 3.8 ± 0.3. Added olefins are rapidly isomerized during the decomposition of 1; trap...
The Stationary Beer Game

This paper presents a variant of the popular beer game. We call the new game the stationary beer game, which models the material and information flows in a production-distribution channel serving a stationary market where the customer demands in different periods are independent and identically distributed. Different players, who all know the demand distribution, manage the different stages of the channel. Summarizing the initial experience with the stationary beer game, the paper provides compelling reasons why this game is an effective teaching tool.
Anti‐Anti‐Multiculturalism

In the tradition of Geertz's "Anti Anti-Relativism," this essay analyzes the clash between multiculturalists and anti-multiculturalists as an exchange of worries and warnings about the dangers inherent in the other ism. It then contrasts the concept of culture as employed by anthropologists and by multiculturalists. Finally, it arrives at the conclusion that, while we as anthropologists should not fully embrace multiculturalism, we should reject anti-multiculturalism.
Uni-vector-sensor ESPRIT for multisource azimuth, elevation, and polarization estimation

This paper introduces a novel eigenstructure-based algorithm uni-vector-sensor ESPRIT that yields closed-form direction-of-arrival (DOA) estimates and polarization estimates using one electromagnetic vector sensor. A vector sensor is composed of six spatially co-located nonisotropic polarization-sensitive antennas, measuring all six electromagnetic field components of the incident wave field. Uni-vector-sensor ESPRIT is based on a matrix-pencil pair of temporally displaced data sets collected from a single electromagnetic vector sensor. The closed-form parameter estimates are obtained through a vector cross-product operation on each decoupled signal-subspace eigenvector of the data correlation matrix. This method exploits the electromagnetic sources' polarization diversity in addition to their spatial diversity, requires no a priori knowledge of signal frequencies, suffers no frequency-DOA ambiguity, pairs automatically the x-axis direction cosines with the y-axis direction cosines, eliminates array interelement calibration, can resolve up to five completely polarized uncorrelated monochromatic sources from near field or far field. It impressively out-performs an array of spatially displaced identically polarized antennas of comparable array-manifold size and computational load.
Fault analysis of switched reluctance motor drives

The switched reluctance machine (SRM) is uniquely reliable for its fault tolerance capabilities. More has been discussed in the literature about fault tolerance of switched reluctance machine than has actually been analyzed. This paper presents a model for various fault analyses which is general enough to be applied to any type of SRM drive as an evaluation tool. The post-fault performance characteristics of the SRM are presented here in terms of torque and speed ripples to show its fault-tolerance capabilities.
Site-directed mutagenesis of hepatocyte nuclear factor (HNF) binding sites in the mouse transthyretin (TTR) promoter reveal synergistic interactions with its enhancer region

The transthyretin (TTR) gene is regulated by two DNA regions which elicit hepatocyte-specific expression: a proximal promoter and distal enhancer. The TTR promoter and enhancer are composed of at least eight DNA binding sites for three different hepatocyte nuclear factors (HNF), CCAAT/enhancer binding protein (C/EBP), and AP-1/cJun. Site directed mutations within each of the HNF binding sites in the TTR promoter were introduced to evaluate their contribution to transcriptional activity in hepatoma cells. The data indicate that the strong affinity HNF-3-S binding site (-106 to -94) is absolutely required for TTR promoter activity since several mutations in this site eliminate TTR expression in the context of its enhancer. Conversion of a second weak affinity HNF3-W site (-140 to -131) in the TTR promoter to a high affinity site resulted in higher levels of expression. TTR mutations that disrupted several weak affinity sites (HNF1, HNF3-W, and HNF4) only slightly diminished expression levels in the presence of the TTR enhancer. In contrast, when we deleted the TTR enhancer from these HNF mutant constructs, TTR expression decreased to undetectable levels. This result suggests cooperation between the factors binding to the TTR promoter and enhancer regions. These results also demonstrate that the HNF3-S site alone is not sufficient to activate TTR transcription, but rather requires the participation of three cell-specific factors to elicit minimal promoter activity. The complexity of this promoter design and the requirement for a minimal number of cell-specific factors to achieve transcription allows us to propose a model which may explain the maintenance of tissue-specific expression of TTR.
Efficient Parallel Buffer Structure and Its Management Scheme for a Robust Network-on-Chip (NoC) Architecture

In this paper, we present an enhanced Network-on-Chip (NoC) architecture with efficient parallel buffer structure and its management scheme. In order to enhance the performance of the baseline router to achieve maximum throughput, a new parallel buffer architecture and its management scheme are introduced. By adopting an adjustable architecture that integrates a parallel buffer with each incoming port, the design complexity and its utilization can be optimized. By utilizing simulation-based performance evaluation and comparison with previous NoC architectures, its efficiency and superiority are proven. Major contributions of this paper are the design of the enhanced structure of a parallel buffer which is independent of routing algorithms, and its efficient management scheme for the Network-on-Chip (NoC) architecture adopting a minimal adaptive routing algorithm. As a result, the total amount of required buffers can be reduced for obtaining the maximum performance. Additionally a simple and efficient architecture of overall NoC implementation is provided by balancing the workload between parallel buffers and router logics.
Aggression, Trauma, and Hatred in the Treatment of Borderline Patients

This article focuses on the etiology of aggressive affect, behavior, and fantasy in the treatment of patients with severe personality disorders in an effort to further our understanding of the psychopathology and treatment of these patients. In the process, the relationship between inborn disposition to aggressive behavior and the effect of severe trauma and psychosocial pathology in early childhood are examined. Various types of transferences marked by aggression and specific approaches to each of these are outlined. Particular reference is given to the management of intense hatred--as a derivative of aggression--in the transference, and of the unconscious identification with both victim and victimizer in patients who have experienced sexual or physical abuse.
cis-Bis(3,6-di­hydro-2H-1,2-oxazine-N)­di­iodo­platinum(II) and cis-bis(3,4,5,6-tetra­hydro-2H-1,2-oxazine-N)­di­iodo­platinum(II)

The title complexes, [Pt(C4H7NO)2I2], (I), and [Pt(C4H9NO)2I2], (II), possess similar square-planar coordination geometries with modest distortions from ideality. For (I), the cis-L—Pt—L angles are in the range 87.0 (4)–94.2 (3)°, while the trans angles are 174.4 (3) and 176.4 (3)°. For (II), cis-L—Pt—L are 86.1 (8)–94.2 (6)° and trans-L—Pt—L are 174.4 (6) and 177.4 (5)°. One 3,6-di­hydro-2H-1,2-oxazine ligand in (I) is rotated so that the N—O bond is out of the square plane by approximately 70°, while the N—C bond is only ca 20° out of the plane. The other oxazine ligand is rotated so that the N—C bond is about 80° out of the plane, while the N—O bond is out of the plane by approximately 24°. In (II), the 3,4,5,6-tetra­hydro-2H-1,2-oxazine ligands are also positioned with one having the N—O bond further out of the plane and the other having the N—C bond positioned in that fashion. Both ligands, however, are rotated approximately 90° compared with their positions in (I). In both complexes, this results in an unsymmetrical distortion of the I—Pt—N bond angles in which one is expanded and the other contracted. These features are compared to those of reported cis-di­amine­di­iodo­platinum(II) complexes.
Strong Stability Preserving Time Discretizations: A Review

Strong stability preserving (SSP) high order time discretizations were developed to address the need for nonlinear stability properties in the numerical solution of hyperbolic partial differential equations with discontinuous solutions. These methods preserve the monotonicity properties (in any norm, seminorm or convex functional) of the spatial discretization coupled with first order Euler time stepping. This review paper describes the state of the art in SSP methods.
Evaluating and Selecting Bases for Conjoint-Based Segmentation

Marketing managers are becoming increasingly interested in using conjoint-based part-worths for market segmentation. Which, among a large number of potential segmentation bases, are most discriminating with respect to showing differences across part-worths? This paper describes a model performing a set of procedures that is designed to assess the value of competing segmentation bases and to profile the resulting target-market prospects. The proposed model is described in the context of an actual business case.
Hierarchical Multi-Scale Approach To Validation and Uncertainty Quantification of Hyper-Spectral Image Modeling

Validating predictive models and quantifying uncertainties inherent in the modeling process is a critical component of the HARD Solids Venture program [1]. Our current research focuses on validating physics-based models predicting the optical properties of solid materials for arbitrary surface morphologies and characterizing the uncertainties in these models. We employ a systematic and hierarchical approach by designing physical experiments and comparing the experimental results with the outputs of computational predictive models. We illustrate this approach through an example comparing a micro-scale forward model to an idealized solid-material system and then propagating the results through a system model to the sensor level. Our efforts should enhance detection reliability of the hyper-spectral imaging technique and the confidence in model utilization and model outputs by users and stakeholders.
The Influence of Streamflow on the Recruitment of Rock Bass in the New River

Abstract Few studies have addressed the effect of stream discharge on Ambloplites rupestris (Rock Bass). We investigated the effects of spawning-season discharge on Rock Bass recruitment in the New River at 2 sites, 5 and 55 miles downstream from Claytor Dam, VA. We back-calculated length at age 1 and 2 using otoliths in order to estimate average lengths and used these values to identify age-1 fish from 14 years of fall electrofishing data on the New River. We determined a catch per unit effort (CPUE) of age-1 fish at each site and correlated it to spawning-season discharge data from the previous year using Spearman's rho rank-correlation. The CPUE at the upstream site was negatively correlated with average and maximum discharge in August, while the CPUE at the downstream site was negatively correlated with average and maximum discharge in July. August and July directly precede spawning season of Rock Bass in Virginia. We surmise that high levels of discharge strongly influence mortality in juvenile Rock ...
Changes in diaphragm motor unit EMG during fatigue.

Fatigue-related changes in the waveform and root-mean-square (rms) values of evoked motor unit electromyographic (EMG) responses were studied in the right sternocostal region of the cat diaphragm. ...
Acetate Causes Endothelium-Independent Increases in Cyclic AMP in Rat Caudal Artery

The mechanism of the vasorelaxant action of acetate is unknown. Because cyclic nucleotides have been linked to vasorelaxation in vascular smooth muscle, we studied the effects of acetate on tissue adenosine 3',5'-cyclic monophosphate (cAMP) and guanosine 3',5'-cyclic monophosphate (cGMP) levels in rat caudal artery. Acetate (4 mM) induced an increase in tissue cAMP levels (control: 5.1 +/- 0.67, acetate: 7.1 +/- 0.97 pmol/mg protein, P less than 0.05), with the increase noted as early as 15-30 s after acetate exposure, and peaking at 60 s. The time course of the cAMP response was compatible with the vasorelaxant effect of acetate against an arginine vasopressin (AVP, 2 X 10(-9) M) contraction. Both the increase in cAMP and the vasorelaxant effect were completely blocked by 10(-3) M 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS). Acetate increased cAMP levels in 3-isobutyl-1-methylxanthine (IBMX)-treated tissue with an effective concentration producing 50% of the maximum response (EC50) of 1.5 mM, similar to the relaxant EC50 (without IBMX) of 2.2 mM against an AVP contraction. In other experiments, the effect of acetate on cAMP was shown to be independent of endothelium. In contrast, acetate had no effect on tissue cGMP levels, whether the endothelium was present or absent. The results suggest that acetate causes an increase in tissue cAMP levels that is not dependent on presence of a functioning endothelium. The changes in cAMP may be contributory to the vasorelaxant effect of acetate in the caudal artery.
Application to Control and Communications

Publisher Summary This chapter introduces problems in classical control and communications and links them with the Laplace and Fourier analyses. The Laplace transform is very appropriate for control problems, where transients as well as steady-state responses are of interest. In communications and filtering there is more interest in steady-state responses and frequency characterizations, which are more appropriately, treated using the Fourier transform. Control and communication systems consist of interconnection of several subsystems such as cascade, parallel, and feedback. Cascade and parallel result from properties of the convolution integral, while the feedback connection relates the output of the overall system to its input. The control examples show the importance of the transfer function and transient and steady-state computations. Block diagrams help to visualize the interconnection of the different systems. Different types of modulation systems are illustrated in the communication examples. The chapter also discusses analog filter design. Filtering is a very important application of linear time invariant (LTI) systems in communications, control, and digital signal processing. This In all the examples, the application of MATLAB was illustrated.