cssi/SciSciGPT-SciSciNet huggingface dataset:
THE CRYSTAL STRUCTURES OF TWO IMINO-1,2,4- DITHIAZOLES FORMED BY THERMAL DECOMPOSITION OF 5-(DIALKYLAMINO)-3-(SUBSTITUTED IMINO)-1,2,4-DITHIAZOLES

Abstract The thermal decomposition products of two substituted imino-1,2,4-dithiazoles have been studied by single crystal x-ray analysis. Both products crystallize in space group P21/c with four molecules per unit cell. The first product, obtained from 5-(dimethylamino)-3-(methylimino)-1,2,4-dithiazole has cell dimensions of a=9.922(8) A, b=12.052(11) A, c=13.358(12) A and β=104.9(1)°. The molecule is made up of two planar segments related by an extremely large twist (−154°) about a C[dbnd]N double bond. The results from this study have also contributed further information in the area of nonbonded interactions between ring and thione sulfur atoms. The second product, from 5-(dimethylamino)-3(phenylimino)-1,2,4-dithiazole was shown to be an ordered 1:1 complex of the starting material and one of its isomers. The cell dimensions are a=12.420(6) A, b=8.840(9) A, c=22.276(22) A and β= 112.2(1)°. The different molecules are linked by an inter molecular NH… N hydrogen bond.
Probing the structural development of dip-coated silica sol-gel thin films via fluorescent probe molecules

Structural formation of dip-coated silica sol-gel thin films is monitored in situ via fluorescence depolarization with luminescent probe molecules. Pyranine (trisodium 8-hydroxy- 1,2,6-pyrenetrisulfonate) and prodan [6-propionyl-2- (dimethylamino)naphthalene] are chosen as the probe molecules for these experiments and are dissolved into the sol gel solution in millimolar quantities. This provides sufficient luminescence intensity without interfering with the film drying process. Fluorescence depolarization yields results which directly correlate to microviscosity increases as the film progresses from liquid to solid. These results allow for further quantitative support of a model previously presented concerning the formation of sol-gel thin films.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Models for the photosynthetic water oxidizing enzyme. 1. A binuclear manganese(III)-β-cyclodextrin complex

A binuclear Mn(III) model compound was synthesized by using ..beta..-cyclodextrin as a ligand. Reaction of the compound with various oxidizing agents has been investigated. The compound in 80:20 DMF-H/sub 2/O was not oxidized by excess potassium ferricyanide. On treatment with two equivalents of Ce(IV), the 482-nm band was bleached. One equivalent produced only partial bleaching, with no evidence again for the intervalence transition for a Mn(III)-Mn(IV) oxidation state. Evidently a two-electron oxidation to the (IV,IV) state is preferred, with eventual decomposition of ligand or water over hours, at least in aqueous DMF and DMSO.
A near infrared study of neteroassociation by di-T-butyl carbinol and choice of concentration scale for molecular complex equilibria

Abstract A study of the heteroassociation of di- t -butyl carbinol with seventeen organic bases in carbon tetrachloride solution mostly at −10° has been carried out using near infrared spectroscopy. The effect of base concentration on the constancy of apparent equilibrium constants favors molarity over molality as the most appropriate concentration scale for use in studies of molecular complex equilibria.
Anterior cingulate conflict monitoring and adjustments in control

Conflict monitoring by the anterior cingulate cortex (ACC) has been posited to signal a need for greater cognitive control, producing neural and behavioral adjustments. However, the very occurrence of behavioral adjustments after conflict has been questioned, along with suggestions that there is no direct evidence of ACC conflict-related activity predicting subsequent neural or behavioral adjustments in control. Using the Stroop color-naming task and controlling for repetition effects, we demonstrate that ACC conflict-related activity predicts both greater prefrontal cortex activity and adjustments in behavior, supporting a role of ACC conflict monitoring in the engagement of cognitive control.
A software tool for simulating motions and loading in planar tensegrity structures

Tensegrity structures are unique in the sense that they tend to be overconstrained as mechanisms, yet they can be mobile due to the elastic nature of their tensile elements. The ability to easily visualize these motion properties would help designers to create new and useful tensegrity mechanisms. In this paper, a simple and interactive computational tool with a graphical user interface is presented for visualizing loading and displacements in tensegrity structures. This tool can also be extended for use with traditional static structures, including both determinate and indeterminate structures, as well as mechanisms.Copyright © 2014 by ASME
Effects of annealing temperature and time on the electrical resistivity of single crystal RNi2B2C (R=Gd–Lu, Y)

Abstract An optimal annealing temperature and time was determined for single crystal samples of the RNi 2 B 2 C series, R=Gd–Lu, Y. For R=Dy–Tm, Lu and Y dramatic improvements in the low temperature resistivity, residual resistivity ratio and implicitly the electronic mean free path were found for annealing temperature T =1000 °C and annealing time t ≈75–100 h. This annealing schedule is somewhat less effective in changing the temperature dependent resistivities of TbNi 2 B 2 C and GdNi 2 B 2 C but it produces dramatic changes in the resistivity of the heavy Fermion compound YbNi 2 B 2 C.
Second-order Optimality Conditions for Optimal Control of the Primitive Equations of the Ocean with Periodic Inputs

We investigate in this article the Pontryagin’s maximum principle for control problem associated with the primitive equations (PEs) of the ocean with periodic inputs. We also derive a second-order sufficient condition for optimality. This work is closely related to Wang (SIAM J. Control Optim. 41(2):583–606, 2002) and He (Acta Math. Sci. Ser. B Engl. Ed. 26(4):729–734, 2006), in which the authors proved similar results for the three-dimensional Navier-Stokes (NS) systems.
Isolation of a human epidermal cDNA corresponding to the 180-kD autoantigen recognized by bullous pemphigoid and herpes gestationis sera. Immunolocalization of this protein to the hemidesmosome.

Abstract Autoantibodies present in the sera of patients with bullous pemphigoid (BP) bind to the basement membrane zone of normal human skin and commonly recognize two epidermal proteins, the BP240 and BP180 antigens. Two BP antigen cDNA clones from a lambda gt11 human keratinocyte library have been identified on the basis of reactivity with a BP serum. The fusion protein (FP) produced by one clone immunoadsorbed autoantibodies, which specifically recognized the BP180 by antigen, showing no cross-reactivity with BP240 by immunoblot analysis. The FP produced by the second clone immunoadsorbed autoantibodies which specifically reacted with the BP240 epidermal antigen. Northern blot analysis demonstrated that the BP180 and BP240 antigens are encoded by distinct RNA transcripts with lengths of 6.0 and 8.5 kb, respectively. Immunoblot analysis of the BP180 lysogen extract identified a 135-kD FP which was recognized by 7 of 16 BP sera and 7 of 8 herpes gestationis sera. A rabbit antiserum prepared against the lysogenic BP180 FP specifically recognized the BP180 antigen from human epidermal extracts by immunoblotting, labeled the BMZ by indirect immunofluorescence, and bound to human epidermal hemidesmosomes by immuno-electron microscopy. These results indicate that the BP180 antigen recognized by BP and herpes gestationis autoantibodies is a unique hemidesmosomal polypeptide, distinguishable from the BP240 antigen.
Double Poincaré sections of a quasi-periodically forced, chaotic attractor☆

Abstract A nonlinear mechanical oscillator is forced with two incommensurate harmonic signals and chaotic vibrations are experimentally observed. The fractal nature of this strange attractor in four-dimensional phase space is revealed by using a double Poincare section. This section involves a narrow timing pulse on one harmonic driving signal and a wider phase window on the other forcing harmonic signal. The resulting two-dimensional map shows a Cantor set structure characteristic of strange attractors. The transition from quasi-periodic to chaotic vibrations is also observed.
The visual perception of rigid motion from constant flow fields

Four experiments investigated observers’ judgments of rigidity for different types of optical motion. The depicted structural deformations were of two types: (1) those with nonparallel image trajectories that are detectable from the first-order spatiotemporal relations between pairs of views; and (2) those with parallel image trajectories that can only be detected from higher order relations among three or more views. Patterns were composed of smooth flow fields in Experiments 1 and 3, and of wire frame figures in Experiments 2 and 4. For both types of display, the nonrigidity detectable from the first-order spatiotemporal structure of the motion sequence was much more salient than the deformation detectable only from the higher order spatiotemporal structure. These results indicate that observers’ judgments of rigidity are based primarily on a two-view analysis, but that some useful information can be obtained under appropriate circumstances from higher order spatiotemporal relations among three or more views.
A quantitative evaluation of ST-segment changes on the 18-lead electrocardiogram during acute coronary occlusions

Abstract This study determined quantitative ST segment changes on the 18-lead electrocardiogram (ECG) during occlusions in each of the coronary arteries. Methods Continuous 18-lead ECGs, including standard 12 leads, posterior (V 7-9 ), and right ventricular (RV) leads (V 3-5R ) were recorded for 155 subjects undergoing percutaneous coronary occlusions, the maximum intervention. Results During 58 left anterior descending (LAD) coronary occlusions, the maximum ST elevation and depression were in V 3 (4.2mm) and III (−0.9mm), respectively. During 44 right coronary artery (RCA) occlusions, the maximum ST elevation and depression were in III (2.2mm) and aVL (−1.4mm), respectively. During 53 left circumflex (LCX) occlusions, the maximum ST elevation and depression were in V 7 (0.8mm) and V 2 (−1.6mm), respectively. Conclusions ST elevation often occurred in the anteroapical (V 1 -V 6 ), lateral (I, aVL), and RV lead V 3R during LAD occlusions; in the inferior, RV, and posterior leads during RCA occlusions; and in the posterior, inferior, and apical leads (V 5 -V 6 ) during LCX occlusions.
Magnetic phases of ultrathin Fe grown on Cu(100) as epitaxial wedges

Magnetic wedges of Fe on Cu(100) are explored magneto-optically. In the region of 6--11 monolayers (ML) of fcc Fe grown at room temperature, in addition to a surface ferromagnetic layer with a Curie temperature \ensuremath{\sim}250 K, the Fe bulk is antiferromagnetic with a N\'eel temperature of \ensuremath{\sim}200 K. This fcc phase is stable only above a growth temperature of order \ensuremath{\sim}200 K, below which the ferromagnetic spin-reorientation transition occurs at \ensuremath{\sim}6 ML. The phase boundaries are delineated by cusps in the coercivity along the wedge.
Training Elementary Mathematics Teachers Using Interactive Multimedia.

Two studies were conducted wherein an interactive, multimedia-based instructional system was piloted with preservice elementary school teachers. Mathematics methods classes experienced conventional instruction with a new interactive technological-instructional system as supplemental course material. An analysis of interview data indicated that students were more likely to incorporate the knowledge they acquired from the system into their teaching repertoire. Many students thought that this mode of presentation enhanced their learning of mathematics teaching methods and their teaching in other fields.
Design of manufacturing cells: Operation assignment in printed circuit board manufacturing

We consider an operation assignment problem that arose from a printed circuit (PC) board assembly process. Components can either be inserted on boards manually or by machine. The objective is to determine an assignment of components (operations) to a set of capacitated machines (with the remainder of the components inserted manually) to minimize the total set-up and processing cost for assembling all boards. The problem can be formulated as a mixed integer linear program, but is too large to be practically solved. For the case of one machine, we present two different solution heuristics. We show that while each can be arbitrarily bad, on average the algorithms perform quite well. For the case of multiple machines, we present four different solution heuristics. We discuss implementation of our results at Hewlett-Packard.
The Return of the Incumbents: the Nature of the Incumbency Advantage:

E OF THE most elementary facts of political life in America is that incumbent members of the House of Representatives are seldom defeated for reelection. Though this fact is commonly acknowledged, there is little agreement as to the reasons for this phenomenon. No doubt a major reason for the success of incumbents is simple inertia. Incumbents are reelected for many of the same reasons that they were elected to begin with. In the space of two years, the political conditions, the voters, the voters' opinions, and the incumbent himself probably change very little. With all of these stable factors it should not be too surprising if one election produces the same results as the last. However, inertia appears to account only partially for the success of incumbents.
A Comparison of Scalar and Root Harmonic Aural Perception Techniques.

Seventy-two seventh- and eighth-grade general music students were taught to identify primary harmonic functions by using either a scalar or root harmonic aural perception technique. Students who were taught the scalar technique attended to the seventh and eighth scale degrees, whereas students who were taught the root technique attended to the root movement of the bass line. An aural identification test battery was used to measure the effectiveness of the two techniques. Although there was no statistically significant difference between the scalar and root techniques on the root position subtest the scalar technique yielded statistically significant higher mean scores on the root/inversion subtest. Thus, the scalar technique appears to be a more effective procedure in teaching general music students to identify primary harmonic functions.
Losing Control: Policy Space to Prevent and Mitigate Financial Crises in Trade and Investment Agreements

This article examines the extent to which measures to mitigate the current financial crisis and prevent future crises are permissible under a variety of bilateral, regional and multilateral trade and investment agreements. US trade and investment agreements, and, to a lesser extent, the World Trade Organization, leave little room to manoeuvre with capital controls, despite increasing evidence that certain controls can prevent or mitigate crises. Investment rules under the treaties of most capital-exporting nations allow for at least the use of temporary controls as a safeguard measure. The article offers a range of policies that could be deployed to improve US investment rules.
CAN HIGH-OCCUPANCY/TOLL LANES ENCOURAGE CARPOOLING? CASE STUDY OF CARPOOLING BEHAVIOR ON THE 91 EXPRESS LANES

A case study of carpooling behavior on the 91 express lanes is presented. The 91 express lanes are the nation's first high-occupancy/toll (HOT) lanes on which carpools with three or more passengers could use the lanes for free (at the time the data for this study were collected) and others paid a toll that varied by time of day to use the premium express lane. One concern over such a policy is that people will not carpool if they can just pay for the travel time savings that they would normally obtain by carpooling and using a high-occupancy vehicle (HOV) lane. Survey data show that the rate of carpooling has not changed much since the opening of the express lanes, a lot of changing between modes occurs (increases and decreases in the number of passengers), a large number of people carpool a few times a week, and two-person HOVs use both the regular lanes and the express lanes. It was further investigated whether HOT lanes encourage carpooling by modeling carpool formation with discrete choice models. The...
Alzheimer's paired helical filaments: Amyloid precursor protein epitope mapping

Abstract Paired helical filaments (PHF) were electro-phoretically purified and solubilized from Alzheimer's neurofibrillary tangles and consisted of a primary 66 kDa protein on SDS-PAGE analysis. A panel of antibodies raised against restricted regions of the beta-amyloid precursor protein (APP) were employed for epitope mapping studies of this 66 kDa PHF protein. Western blot studies revealed that C-terminal APP antibodies were immunoreactive with the 66 kDa PHF protein. Further analysis revealed that only antisera raised against peptides that include the beta/A4-amyloid region within the C-terminal portion of APP were immunoreactive with PHF proteins. These data complement previous immunocytochemical studies which indicated that C-terminal APP antibodies preferentially label PHF-containing neurofibrillary tangles in Alzheimer's brain. The present data suggest a similarity of secondary or tertiary structure between beta/A4-amyloid and PHF which accounts for the cross-reactivity of beta/A4-amyloid antibodies with PHF proteins.
Mechanisms of Estradiol-Induced Insulin Secretion by the G Protein-Coupled Estrogen Receptor GPR30/GPER in Pancreatic β-Cells

Sexual dimorphism and supplementation studies suggest an important role for estrogens in the amelioration of glucose intolerance and diabetes. Because little is known regarding the signaling mechanisms involved in estradiol-mediated insulin secretion, we investigated the role of the G protein-coupled receptor 30, now designated G protein-coupled estrogen receptor (GPER), in activating signal transduction cascades in β-cells, leading to secretion of insulin. GPER function in estradiol-induced signaling in the pancreatic β-cell line MIN6 was assessed using small interfering RNA and GPER-selective ligands (G-1 and G15) and in islets isolated from wild-type and GPER knockout mice. GPER is expressed in MIN6 cells, where estradiol and the GPER-selective agonist G-1 mediate calcium mobilization and activation of ERK and phosphatidylinositol 3-kinase. Both estradiol and G-1 induced insulin secretion under low- and high-glucose conditions, which was inhibited by pretreatment with GPER antagonist G15 as well as depletion of GPER by small interfering RNA. Insulin secretion in response to estradiol and G-1 was dependent on epidermal growth factor receptor and ERK activation and further modulated by phosphatidylinositol 3-kinase activity. In islets isolated from wild-type mice, the GPER antagonist G15 inhibited insulin secretion induced by estradiol and G-1, both of which failed to induce insulin secretion in islets obtained from GPER knockout mice. Our results indicate that GPER activation of the epidermal growth factor receptor and ERK in response to estradiol treatment plays a critical role in the secretion of insulin from β-cells. The results of this study suggest that the activation of downstream signaling pathways by the GPER-selective ligand G-1 could represent a novel therapeutic strategy in the treatment of diabetes.
The enterprise “model” of organized crime: Assessing theoretical propositions

In recent years, the study of organized crime has been oriented around the enterprise “model.” This model is really an approach to studying organized crime, founded on the notion that legal and illegal businesses are quite similar. This notion provides the method used by enterprise theorists: theories established for studying formal legal organizations are applied to the study of businesses that provide illegal goods and services. The most noteworthy research based on the enterprise approach is that of economist Peter Reuter. Reuter used principles of industrial organization and marketplace dynamics to predict that illegal enterprises will be relatively small and shortlived, and that illegal markets will be characterized by competition, not by collusion. Here I seek to assess the degree to which Reuter's propositions were confirmed or disconfirmed by observations of the numbers gambling industry in New York City in the 1960s. Most of Reuter's propositions were not supported by the data used in this study.
Improving the Efficiency of an Emergency Department

"Voice of the Stakeholder" data collected from Patients and Hospital Administrators showed that both groups believe that "time to see a doctor" is the most critical metric in an Emergency Department ED. Further research determined that controlling "inpatient bed assignments" was the most critical in-process variable to effect the "time to see a doctor." This paper reports a dramatic reduction in the average time a patient waits to see a doctor in an Emergency Department, as well as improvements in other key metrics.
Humoral hypercalcemia of malignancy in a patient with large cell carcinoma of the lung: report of case and review of literature

Objective: To report a case of hypercalcemia associated with parathyroid hormone-related protein (PTHrP) in large cell carcinoma of the lung.Methods: We present a case of PTHrP-mediated hypercalcemia in a patient with a large cell carcinoma of the lung and review the related literature.Results: A 43-year-old African American man required medical attention because of lethargy, confusion, and poor oral intake. He had bullous emphysema attributable to a 50-pack-year smoking history. On physical examination, vital signs were normal, he was oriented to place and person but not time, and he had cachexia. Breath sounds were decreased in the left lower lung field. Findings on cardiac and abdominal examination were normal. Results of laboratory studies (and corresponding reference ranges) were as follows: calcium 12.1 mg/dL (8.5 to 10.5), albumin 2.0 g/dL (3.5 to 5.0), phosphorus 2 mg/dL (2.5 to 4.5), alkaline phosphatase 68 U/L (40 to 150), intact parathyroid hormone 5 pg/mL (10 to 60), PTHrP 7.0 pmol/L (0.0 to 1...
Collaborative Tagging Applications and Approaches

This article reviews the state of the art in collaborative tagging, its current challenges, and potential methods for resolving these challenges, with a special focus on Web-based, user-generated content applications.
Clay intercalation catalysts interlayered with rhodium phosphine complexes. Surface effects on the hydrogenation and isomerization of 1-hexene

Abstract Clay intercalation catalysts formed by interlayering of Na+-hectorite with rhodium phosphine complexes of the type Rh(NBD)(PPh3)2+ and Rh(NBD)(dppe)+, where NBD = norbornadiene and dppe = 1,2-bis(diphenylphosphino)ethane, were examined as catalyst precursors for the hydrogenation-isomerization of 1-hexene in methanol. Relative to reaction under homogeneous solution conditions, the intercalated catalysts exhibit a much lower tendency to isomerize the substrate to the less reactive internal olefin 2-hexene. In the case of Rh(NBD)(PPh3)2+-hectorite, the dramatic dependence of the hexane: 2-hexene product ratio on substrate concentration and water content indicates that the intrinsic Bronsted acidity of partially hydrated Na+ ions in the clay interlayers causes the protonic equilibrium between surface intermediates responsible for the isomerization and hydrogenation pathways to be shifted in favor of hydrogenation. Rh(NBD)(dppe)+-hectorite also favors hydrogenation over isomerization relative to homogeneous solution. In this case, however, a catalytically important protonic equilibrium is not involved in the reaction mechanism, and the reaction is insensitive to factors which influence surface acidity. The results demonstrate that surface chemical effects can dramatically alter the catalytic properties of metal complexes immobilized in clay interlayers.
A Fast, Wide Field of View, Catadioptric Telescope for Whipple

We describe the optical design of a space bourn f/1.3 catadioptric telescope with a 9 degree field and 77 cm aperture that is being proposed to study objects in the Kuiper belt, Sedna Region, and Oort cloud.
Interferon γ Repression of Collagen (COL1A2) Transcription Is Mediated by the RFX5 Complex

Interferon γ (IFN-γ) plays an important physiological role during inflammation by down-regulating collagen gene expression and activating major histocompatibility II (MHC-II) complex. The activation of MHC-II by IFN-γ requires activation of a trimeric DNA binding transcriptional complex, RFX5 complex, containing RFXB (also called RFXANK or Tvl-1), RFXAP, as well as RFX5 protein. Previously, we demonstrated that RFX5 binds to the collagen transcription start site and represses collagen gene expression (Sengupta, P. K., Fargo, J., Smith, B. D. (2002) J. Biol. Chem. 277, 24926–24937). In this report, we have examined the role of RFXB and RFXAP proteins within the RFX5 complex to regulate collagen gene expression. The data show that all three RFX5 complex proteins are required for maximum repression. Expression of proteins with mutations known to be important for RFX5 complex formation does not repress collagen promoter activity. Two mutated forms of RFX5 act as dominant negative proteins activating collagen expression and reversing IFN-γ down-regulation of collagen expression in human lung fibroblasts. IFN-γ increases expression and nuclear translocation of RFX5. RFXB has a naturally occurring splice variant isoform (RFX SV). Interferon increases expression of the long form of RFXB and decreases expression of RFX SV with the same kinetics as collagen gene expression. Overexpression of the splice variant form reverses the IFN-γ induced collagen repression in human lung fibroblasts. Finally, all three RFX5 complex proteins increase at the collagen transcription start site with IFN-γ treatment using chromatin immunoprecipitation analysis. Thus, these studies suggest an important role for RFX5 complex in collagen repression.
High resolution CT of the porta hepatis and hepatoduodenal ligament

The authors present a detailed analysis of the sectional anatomy of the porta hepatis and hepatoduodenal ligament, and illustrate the use of high resolution CT in the clinical evaluation of the area.
Rhabdomyolysis: a review, with emphasis on the pediatric population

Rhabdomyolysis is a common clinical syndrome and accounts for 7% of all cases of acute kidney injury (AKI) in the USA. It can result from a wide variety of disorders, such as trauma, exercise, medications and infection, but in the pediatric population, infection and inherited disorders are the most common causes of rhabdomyolysis. Approximately half of patients with rhabdomyolysis present with the triad of myalgias, weakness and dark urine. The clinical suspicion, especially in the setting of trauma or drugs, is supported by elevated creatinine kinase levels and confirmed by the measurement of myoglobin levels in serum or urine. Muscle biopsy and genetic testing should be performed if rhabdomyolysis is recurrent or metabolic myopathy is suspected. Early recognition is important to prevent AKI through the use of aggressive hydration. Prevention is important in patients with inherited forms, but novel therapies may be developed with the better understanding of the pathophysiology and genetics of rhabdomyolysis.
Psychopathology in human immunodeficiency virus infection: Lifetime and current assessment

Abstract The present study determined lifetime and current psychiatric functioning in a sample of homosexual or bisexual men at various stages of human immunodeficiency virus (HIV) infection in order to address several questions regarding the relationship between psychopathology and HIV infection. HIV + asymptomatic or symptomatic and HIV − homosexual or bisexual men completed self-report measures of psychological and health functioning and participated in structured diagnostic interviews. Additional information regarding HIV-related life events and their potential relationship to onset of disorder and family history of psychiatric disorder were obtained. A high lifetime prevalence of affective and substance use disorder was found, with almost one half of the sample meeting criteria for both disorders. Lifetime affective disorder diagnosis was associated with a positive family history of affective disorder. HIV-related events were most closely associated with onset or recurrence of affective disorder compared with other disorders. Low current rates of psychiatric disorder and levels of emotional distress were found, with no differences in degree of psychiatric adjustment across stage of infection. We conclude that the lifetime prevalence of certain categories of psychiatric disorder is high in both HIV + and HIV − homosexual samples. Increased rates of psychiatric disorders do not appear to be a consequence of HIV infection. However, episodes of illness, particularly affective disorder, may develop following an HIV-related event such as confirmation of infection. Although symptomatic subjects have more somatic difficulties, there appears to be no relationship between stage of illness and level of emotional distress.
Polarization Properties of Corner Reflectors and Cavities

The polarization properties of single-corner reflectors and of certain types of cavities using corner reflectors are investigated and described. States of polarization are found which remain invariant under transmission. Particular attention is given to the lossless case of total internal reflection.
Molecular motion in solid methane

Abstract The rotational heat capacity derived from the observed heat capacity of solid methane in the high-temperature phase is compared with the rotational heat capacity predicted by King's model. From the comparison it is concluded that the barrier to rotation is about 150 calories.
Nine constructs of cultural competence for curriculum development.

Objective. To examine the self-administered Clinical Cultural Competency Questionnaire (CCCQ) and assess the perceived level of cultural competence of students in Xavier University of Louisiana College of Pharmacy to guide curriculum development within the 4-year academic program. Methods. The CCCQ was administrated to each class of pharmacy students during spring 2009. Exploratory factor analysis with principal components and varimax rotation was conducted to build the constructs explaining the factors measuring students' self-assessment of cultural competence. Results. Nine factors, including 46 items extracted from the CCCQ and explaining 79% of the total variance, were found as the best fit to measure students' self-assessment of cultural competence. Conclusions. The CCCQ was found to be a practical, valid, and reliable self-assessment instrument to measure the perceived level of pharmacy students' knowledge, skills, attitudes, and encounters in cross-cultural environments. The questionnaire allowed t...
Bounds for the Optimal Scheduling of n Jobs on m Processors

The problem of scheduling n jobs on m identical processors has been introduced by R. McNaughton, but as yet no efficient algorithm has been found for determining an optimal sequencing of jobs. In this paper lower and upper bounds are given for the cost of an optimal schedule. Since the two bounds are not far apart, they may be helpful in practical scheduling problems. A procedure is described for obtaining a schedule which costs less than the given upper bound.
Evaluation of sensing properties of stiffness-sensitive electret microphones

This paper presents an evaluation of the sensing properties of a new thin-film stiffness sensing technology that utilizes commercial electret microphones. The analysis is intended to provide researchers with both quantitative and qualitative information on microphone selection for stiffness sensing applications. The sensing properties examined include sensitivity, selectivity and the effect of microphone's electric field. Specifically, a mathematical method to estimate the stiffness sensitivity of a commercial microphone from its acoustic sensitivity is presented. This method utilizes direct measurements of the microphone's parameters to compute sensitivity to thin-film stiffness changes. The discussion on selectivity focuses on undesired cross-stiffness changes in the microphone membrane in the presence of changes in unrelated environmental analytes. Finally, the influence of the microphone's electric field on its stiffness sensing ability is presented.
Influence of perched groundwater on base flow

[1] Analysis with a three-dimensional variably saturated groundwater flow model provides a basic understanding of the interplay between streams and perched groundwater. A simplified, layered model of heterogeneity was used to explore these relationships. Base flow contribution from perched groundwater was evaluated with regard to varying hydrogeologic conditions, including the size and location of the fine-sediment unit and the hydraulic conductivity of the fine-sediment unit and surrounding coarser sediment. Simulated base flow was sustained by perched groundwater with a maximum monthly discharge in excess of 15 L/s (0.6 feet3/s) over the length of the 2000-m stream reach. Generally, the rate of perched-groundwater discharge to the stream was proportional to the hydraulic conductivity of sediment surrounding the stream, whereas the duration of discharge was proportional to the hydraulic conductivity of the fine-sediment unit. Other aspects of the perched aquifer affected base flow, such as the depth of stream penetration and the size of the fine-sediment unit. Greater stream penetration decreased the maximum base flow contribution but increased the duration of contribution. Perched groundwater provided water for riparian vegetation at the demand rate but reduced the duration of perched-groundwater discharge nearly 75%.
The Role of Light and Oxygen in Chaoborus punctipennis (Insecta: Diptera) Diel Vertical Migration

ABSTRACT Aquatic phantom midge larvae (Chaoborus punctipennis) exhibit diel vertical migration (DVM) in response to fish visual predation, remaining in deeper waters during the day and ascending nocturnally to feed. Light penetration into the water column and dissolved oxygen concentrations are hypothesized to determine the depths where larvae are found during daylight hours. We collected samples in Yellow Poplar Tree Lake in Millington, Tennessee before and after sunset during a day in March, May, July, and September of 2005. Average daytime depth (Dc) and use of daytime refugia (dark or hypoxic waters) were significantly different (P<0.05) among larval instars (I/II<III<IV) in May, July, and September when the lake was highly stratified. Final instars utilized hypoxic waters (DO2 <3.5 mg/L) more than III instars, while I/II instars did not use this refuge. When the lake was highly stratified, the average depth of all instars during daylight hours was below the depth of maximum light penetration (1.0 μEi...
Thermal properties of infrared absorbent gold nanoparticle coatings for MEMS applications

a b s t r a c t This report presents characterization of the optical absorption and thermal properties of a thin-film plat- inum device coated with gold nanoparticles. These particles are engineered to have a light absorption peak near 808 nm. The response of bare and particle-coated thin-film platinum was examined under an 808 nm infrared laser. The results show that a particle coating is a significant factor in the thermal effi- ciency. This work is the foundation for wavelength-specific microelectromechanical actuators powered by infrared light.
Biomedical research applications of a novel double-layer parallel-plate flow chamber

Since integrity and functions of vascular endothelial cells are greatly affected by shear stress, a variety of in vitro systems to subject endothelial cells under precisely controlled fluid conditions has been developed. Complicated designs of the conventional flow devices, however, have impeded such implementation. In the present study, we designed and developed a novel parallel-plate flow chamber (PPFC). It consists of multiple layers of different materials to adjust the required geometries of the chamber and provide a wide span of biomedical research applications. Because the chamber stacks separate layers to constitute the flow channel, different pieces can be easily removed or replaced. Moreover, the multilayer design only requires 2D cutting, which is easier and faster to manufacture. It is also capable of accepting up to four glass slides facing each other so that the flow within the channel is exclusively formed by endothelial cells. Furthermore, it minimizes the pressure loss across the chamber while maximizing the effective area of endothelial cells up to 96 cm. Results from mathematical analysis and dye injection experiments showed that a uniform magnitude of shear stress is applied throughout the entire surface of endothelial cells. In addition, the morphological changes and attenuated gene expression of proinflammatory mediators were observed in endothelial cells exposed to the physiologically
Pre‐ and postbuckling response of curved, thin, composite panels with cutouts under compression

Analytical predictions of the postbuckling response of curved composite panels are difficult, especially under in-plane compression, because of the presence of snap-back with a steep negative slope beyond the bifurcation point. In this study, the pre- and postbuckling response of curved laminated panels with cutouts is investigated by developing a new finite element based on the free formulation. This trianguiar, flat, shell element, in conjunction with the updated Lagrangian form of the co-rotational approach, accounts for the coupling terms arising from general material anisotropy, as well as large displacements and rotations. The analysis predictions correlate well with the corresponding experimental data available in the literature. Review of the studies in this subject area reveal that none of the available methods, including the STAGS-C1 finite element program, is capable of providing the full description of the postbuckling phenomenon beyond bifurcation for curved composite panels with small cutouts.
Lysosomes in Tetrahymena pyriformis. I. Some properties and lysosomal localization of acid hydrolases.

In homogenates of Tetrahymena pyriformis, five hydrolases — phosphatase, ribonuclease, deoxyribonuclease, proteinase, amylase — with acid pH optima were found. Over 75% of their activity is sedimentable with a centrifugal force of 250,000 g. min. Only 17% of the acid phosphatase and ribonuclease is active when assayed in the presence of 0.25 M sucrose at 0°. Exposure to a lowered osmotic pressure, freezing and thawing, and incubation at temperatures over 0° result in activation of the latent phosphatase and ribonuclease. After isopycnic centrifugation in a sucrose density gradient the hydrolases show a broad distribution which differs greatly from those of enzymes associated with mitochondria (succinate dehydrogenase) or with peroxisomes (catalase). The results are interpreted as evidence that the five acid hydrolases studied are localized in lysosomes which represent a distinct population of subcellular particles in Tetrahymena.
Antecedents and Consequences of Coaching Behavior

Proponents of the learning organization acknowledge that leaders and managers must assume roles as coaches in organizations that aspire to become learning organizations. The concept of the manager as coach is becoming increasingly popular as a way to facilitate learning and improve employee performance. Yet, despite the research that has been done on coaching, studies generally focus on characteristics of good coaches, requisite coaching skills, and employees' perceptions of the improvement in managers' coaching skills following such training programs. This article describes some of the findings from a larger qualitative critical incident study. Specifically, the triggers for coaching and the outcomes of coaching interventions for the individual employee, manager, and organization are examined and reported here. This study identifies gaps and discrepancies, political, and developmental issues as the primary triggers for coaching. Additionally, this study suggests that managers' commitment to coaching has the potential to impact performance at the individual employee, manager, and organizational level.
Comments on time-to-frequency and frequency-to-time domain matrix formulations

This is a discussion of previous letters in the PROCEEDINGS and includes two possible extensions on the formulation of matrix coefficients.
Bottleneck-mediated quasispecies restriction during spread of an RNA virus from inoculation site to brain.

The amplification of RNA viruses such as poliovirus is associated with high error rates, and the resulting diversity likely facilitates viral survival within an infected host. However, within individual tissues of infected hosts, there may be barriers to viral spread that limit genome sampling. We tested whether poliovirus population diversity was maintained during viral spread to the brain of poliovirus receptor-expressing mice. Each of four restriction enzyme site-tagged viruses was shown to be able to replicate in the mouse brain. However, when infection was initiated by i.m., i.v., or i.p. routes, only a subset of the members of the injected pool was detectable in the brain. This jackpot effect was the result of a bottleneck in viral transit from the inoculation site to the brain. The bottleneck was difficult to overcome, requiring a 107 increase in viral inoculum to allow representation of all or most members of the infecting pool. Therefore, the bottleneck is not likely to be a physical barrier but an antiviral state induced by a founder virus. We suggest that the innate immune response can limit viral pathogenicity by limiting the number and therefore the diversity of viruses during spread to vulnerable tissues.
Examining feedback in interactive video retrieval

This paper presents a user-centred video retrieval, or video digital library, study that examines different types of feedback. Separate user interface features, including one that collects and one that presents feedback, shape the evaluation of this study. Research questions were posed to examine both types of feedback and to measure the influence of certain factors on each. The experimental factors examined here, in association with feedback, included user actions, topic characteristics, search duration, levels of user satisfaction and domain familiarity. Laboratory-style search experiments employing 28 users from the field of science education were conducted, which asked the users to attempt six pre-designed search topics. Actions of the users and topic durations were recorded, and users were given a post-search questionnaire about the topics and their experiences and impressions of the experimental system. Results showed that users regularly requested feedback about a clip, beyond a keyframe, while searching, not browsing, and that requests varied significantly across certain topic categories. Findings also indicated that users' requests for feedback were more general interactions and not associated with a search topic's representation of the domain. On the other hand, users rarely contributed feedback about the relative importance of visual vs semantic qualities of search results in order to reformulate queries, regardless of any other experimental factor.
A new methodology for calculating distributions of reward accumulated during a finite interval

Markov reward models are an important formalism by which to obtain dependability and performability measures of computer systems and networks. In this context, it is particularly important to determine the probability distribution function of the reward accumulated during a finite interval. The interval may correspond to the mission period in a mission-critical system, the time between scheduled maintenances, or a warranty period. In such models, changes in state correspond to changes in system structure (due to faults and repairs), and the reward structure depends on the measure of interest. For example, the reward rates may represent a productivity rate while in that state, if performability is considered, or the binary values zero and one, if interval availability is of interest. We present a new methodology to calculate the distribution of reward accumulated over a finite interval. In particular, we derive recursive expressions for the distribution of reward accumulated given that a particular sequence of state changes occurs during the interval, and we explore paths one at a time. The expressions for conditional accumulated reward are new and are numerically stable. In addition, by exploring paths individually, we avoid the memory growth problems experienced when applying previous approaches to large models. The utility of the methodology is illustrated via application to a realistic fault-tolerant multiprocessor model with over half a million states.
Components of the Salmonella Flagellar Export Apparatus and Classification of Export Substrates

Until now, identification of components of the flagellar protein export apparatus has been indirect. We have now identified these components directly by establishing whether mutants defective in putative export components could translocate export substrates across the cytoplasmic membrane into the periplasmic space. Hook-type proteins could be exported to the periplasm of rod mutants, indicating that rod protein export does not have to precede hook-type protein export and therefore that both types of proteins belong to a single export class, the rod/hook-type class, which is distinct from the filament-type class. Hook-capping protein (FlgD) and hook protein (FlgE) required FlhA, FlhB, FliH, FliI, FliO, FliP, FliQ, and FliR for their export to the periplasm. In the case of flagellin as an export substrate, because of the phenomenon of hook-to-filament switching of export specificity, it was necessary to use temperature-sensitive mutants and establish whether flagellin could be exported to the cell exterior following a shift from the permissive to the restrictive temperature. Again, FlhA, FlhB, FliH, FliI, and FliO were required for its export. No suitable temperature-sensitive fliQ or fliR mutants were available. FliP appeared not to be required for flagellin export, but we suspect that the temperature-sensitive FliP protein continued to function at the restrictive temperature if incorporated at the permissive temperature. Thus, we conclude that these eight proteins are general components of the flagellar export pathway. FliJ was necessary for export of hook-type proteins (FlgD and FlgE); we were unable to test whether FliJ is needed for export of filament-type proteins. We suspect that FliJ may be a cytoplasmic chaperone for the hook-type proteins and possibly also for FliE and the rod proteins. FlgJ was not required for the export of the hook-type proteins; again, because of lack of a suitable temperature-sensitive mutant, we were unable to test whether it was required for export of filament-type proteins. Finally, it was established that there is an interaction between the processes of outer ring assembly and of penetration of the outer membrane by the rod and nascent hook, the latter process being of course necessary for passage of export substrates into the external medium. During the brief transition stage from completion of rod assembly and initiation of hook assembly, the L ring and perhaps the capping protein FlgD can be regarded as bona fide export components, with the L ring being in a formal sense the equivalent of the outer membrane secretin structure of type III virulence factor export systems.
Human Resource Strategy and Career Mobility in Professional Service Firms: A Test of an Options-Based Model

This study provides a partial test of our options-based model of career mobility in professional service firms (Malos & Campion, 1995). After clustering a sample of 117 high-grossing U.S. law firms...