cssi/SciSciGPT-SciSciNet huggingface dataset:
Price and Quality of Desktop and Mobile Personal Computers: A Quarter-Century Historical Overview

When introduced in 1976, personal computers (PC’s) had only several kilobytes of randomaccess memory (RAM) and no hard disk, processed commands at speeds of less than 1 megahertz (MHz), yet typically cost several thousand dollars. Today’s PC’s have megabytes (MB) of RAM and gigabytes of hard-disk memory, process commands at speeds exceeding 1,000 MHz, and often cost less than $1,000. Ever more powerful PC boxes have been transformed into increasingly smaller and lighter notebooks. In the context of such rapid technological progress, government statistical agencies face the formidable tasks of reliably tracking real output growth in the PC industry, and adjusting PC prices for quality changes. In 1986, following collaboration with IBM researchers, the Bureau of Economic Analysis (BEA) began adjusting mainframe computer prices for quality change, using hedonic price methods (Rosanne Cole et al., 1986). In 1990, the Bureau of Labor Statistics (BLS) first published an experimental price index for mainframe computers, also based on hedonic methods. Today the BLS publishes producer and consumer price indexes for a number of electronic goods, including informationprocessing equipment, using hedonic price methods (Dennis Fixler et al., 1999). The hedonic regression methods employed by researchers and government statisticians to adjust PC prices for quality changes are usually based on pooled cross-section and time-series data, and they typically assume some parameter equality across models, as well as some parameter stability over time. Here we report on results from an examination of the stability of annual PC hedonic price parameters over almost the first quarter-century of their history (1976–1999), and on the equality of estimated hedonic price parameters between desktop and mobile models. We compute price indexes based on alternative assumptions concerning parameter equality and stability, and we assess at what point in time, when constructing price indexes, mobile and desktop models were appropriately treated as distinct product groups.
A review of numerical fluids/structures interface methods for computations using high-fidelity equations

Abstract Domain decomposition approaches require efficient interface techniques when fluids and structures are solved in independent computational domains for aerospace applications. Fluid/structure interfacing techniques for solutions from equations based on low-fidelity approaches that are in the linear domain are well advanced and are incorporated in production codes NASTRAN and ASTROS. However, for computations involving high-fidelity equations such as the Navier–Stokes for fluids and finite elements for structures, interface approaches are still under development. This paper provides a technical overview of methods for interfacing flow solutions from the Euler/Navier–Stokes methods with structural solutions using modal/finite-element methods. Validity of the methods is supported by previously presented results.
Reactions of VX, GD, and HD with nanotubular titania

Reactions of VX [O-ethyl-S-(2-diisopropylethylamino)ethyl methylphosphonothioate], GD (pinacolyl methylphosphonofluoridate), and HD [bis(2-chloroethyl) sulfide] have been examined with nanotubular titania (NTT) using 31P and 13C MAS NMR. All three agents hydrolyze on NTT with the reaction of VX being notably fast (t1/2 < 30 min), approaching the rate achievable with liquid decontaminants. 31P MAS NMR reveals that VX is adsorbed within the NTT tubules and/or its titania layers, perhaps providing optimum conditions for its hydrolysis by water sandwiched between the layers. Consistent with the availability of copious water on NTT, HD is hydrolyzed to its CH-TG sulfonium ion. GD hydrolysis is similarly efficient, with its products—PMPA and HF—attacking the titania structure to form a titanophosphonate species.
Mean delay in synchronous packet networks with priority queueing disciplines

A Markov model which approximates the behavior of networks that transport messages of varying priority classes is developed. The model is shown to accurately predict behavior for a tandem network with departures and an unidirectional loop network. In the cases which required approximation, the model was validated by performing extensive computer simulation and comparing it with analytical results. >
Electrophoretic Characterization of Bovine Lipoprotein Subfractions Isolated by Agarose Gel Chromatography

Abstract Lipoproteins isolated from whole bovine serum were applied to agarose gel columns and fractionated by molecular size. Three distinct lipoprotein absorbance peaks (280nm) emerged from the columns (Peaks I, II, and III). A typical elution profile exhibited lipoprotein distribution of approximately 11% Peak I, 6% Peak II, and 83% Peak III. Characterization of Peak I lipoproteins on agarose gel electrophoresis and polyacrylamide gel electrophoresis suggested that Peak I consisted of very low density lipoproteins. Comparison of polyacrylamide gel electrophoresis patterns of successive tube fractions in Peak II demonstrated the progressive emergence of three bands. The slowest migrating band appeared in fractions from the ascending portion of Peak II. Two additional bands progressively emerged from fractions in the central portion of the peak. These bands may represert low density lipoprotein and its metabolic precursors (intermediate density lipoproteins). Successive tube fractions in the area between Peaks II and III displayed a progressive change from β to α migration on both polyacrylamide gel electrophoresis and paper electrophoresis. This heterogeneous group of lipoproteins is probably equivalent to high density lipoprotein-subfraction 1. Lipoproteins from the center of Peak III demonstrated a electrophoretic migration patterns.
Spatial distribution of a deep‐sea crinoid Pentametrocrinus tuberculatus in the Izu‐Ogasawara Arc, western Pacific

Spatial distribution of a deep-sea crinoid Pentametrocrinus tuberculatus was investigated in the Izu-Ogasawara Arc, western Pacific. Photographic and video recordings coupled with direct visual observations were conducted from the manned submersible Shinkai 2000 between the depths of 1340 and 1840 m on the south-western slope of the An'ei Seamount (29° 15'N, 138° 37'E). Close to the seabed, temperature, salinity and dissolved oxygen concentration were in the range of 2.2–3.1 °C, 34.38–34.52 and 1.40–2.15 ml l−1, respectively, and the bottom substratum consisted mainly of flat-surfaced lava rocks covered by thin manganese oxide crusts. Pentametrocrinus tuberculatus individuals were attached to the surface of lava rocks with their five arms extended horizontally and showed no recognizable movement. Incidence of arm loss (which may indicate mechanical damage or predation pressure) was very low. The highest density of P. tuberculatus occurred in an area termed ‘terrace’ where the slope was reduced above a relatively steep hillside. Analysis of nearest neighbour distances showed that P. tuberculatus individuals generally demonstrate regular spacing with either no or partial overlap of their ambits (= circular area defined by the extended arms), due to a combination of aggregative tendency (to form patches) and behavioural spacing among individuals within a patch. The observed pattern of distribution was clearly different from the pattern expected from random occurrence of individuals in space. Thus, on spatial scales of 101 to 103 m, P. tuberculatus showed a contagious or aggregated distribution, while on smaller scales and in areas where crinoids were concentrated they showed a combination of patch formation and regular distribution of individuals.
Acute vs. chronic compressive neuropathy

Studies of the management of acute and chronic compressive peripheral neuropathies have not kept pace with advances in our understanding of the pathophysiology of these disorders. In this review, the pathophysiological differences between acute and chronic compressive neuropathy are reviewed from experimental models as well as from clinical examples in humans. It is concluded that surgical intervention is unlikely to alter significantly the course of recovery in acute compressive neuropathies. Similarly, in chronic compressive neuropathies without progressive weakness, conservative treatment is indicated because of the high incidence of spontaneous improvement. However, in patients with progressive weakness, especially in conjunction with electrophysiological evidence of partial denervation or conduction block (but not simply slowing of nerve conduction), surgical treatment is recommended.
Mentorship During Fellowship

“A good mentor not only makes you a better cardiologist but a better human being.” These were the words from my mentor, Dr. Samir Kapadia, when I first approached him about embarking on research projects during my internship year. Although this appeared to be routine advice at first, I have
Nucleic acid probe characterizes Leptospira interrogans serovars by restriction fragment length polymorphisms.

Abstract Restriction endonuclease analysis (REA) of genomic DNA can discriminate between many Leptospira interrogans serovars. However, several serovars have similar restriction endonuclease digestion patterns which prohibits accurate identification. This investigation expands previous REA studies of L. interrogans to include serovars in serogroup Tarassovi. Most serovars in this serogroup had characteristic digestion patterns by which they could be identified. However, four of the serovars in this serogroup had similar digestion patterns, thus preventing serovar identification by REA alone. To discriminate between these serovars REA was supplemented with Southern blot analysis. The DNA from each serovar showed similar but unique patterns when hybridized with a probe synthesized from a repetitive sequence element cloned from L. interrogans serovar hardjo type hardjo-bovis. The applicability of this technique to characterize other serogroup was assessed. One hundred sixty six of 190 serovars screened by Southern blot analysis contained sequences which hybridized with the repetitive element probe under conditions of relaxed stringency. These results suggest that Southern blot analysis using this probe will be a valuable supplement for typing L. interrogans .
Inexpensive Small-Scale Sonochemistry with Magnetic Agitation

A reduction, esterification, acetylation, an ether synthesis, and an aryl nucleophilic substitution are performed in a microwave oven.
Empirical Dependence of Elastic Moduli on Porosity for Ceramic Materials

Twenty-seven sets of elastic modulus-porosity data spanning ranges > 20% in porosity were fitted by linear, exponential, Hasselman, and 2/3-power relations. The fits were tested for goodness of fit, for extrapolation to zero-porosity moduli, and for consistency in determining zero-porosity Poisson's ratios and bulk moduli. On the whole, the linear relation appears to give a superior fit. This result is seen as supportive of self-consistent theoretical calculations of moduli in porous media. Nonlinear data sets are attributed to a tendency for the spheroidicity of pores to increase with porosity.
Central corneal thickness measurements in normal dogs: a comparison between ultrasound pachymetry and optical coherence tomography.

Objective To compare central corneal thickness (CCT) measurements obtained from normal canines using a spectral-domain optical coherence tomography device (SD-OCT) and an ultrasonic pachymeter. Animals Fifteen clinically normal dogs. Procedures Dogs were briefly anesthetized with propofol. Central corneal thickness measurements were obtained from both eyes of each animal four times by one operator using a SD-OCT system. The CCT was automatically calculated using the pachymetry software generated from eight radial scans, 6 mm in length. Ultrasonic pachymetry was then performed in both eyes of each animal by one operator five times in succession. The CCT was recorded for each modality and compared statistically for agreement and bias. Results Fifteen dogs (seven castrated male, eight spayed female) with a mean age of 2.3 ± 1.3 years were examined. The mean CCT for all eyes examined via SD-OCT and ultrasonic pachymetry (velocity set at 1636 m/s) was 587.72 ± 32.44 μm and 598.54 ± 32.28 μm, respectively. Ultrasonic pachymetry consistently overestimated CCT as compared to OCT by a mean value of 10.82 μm (P < 0.0001). No significant difference in CCT was found based on the age or sex of the animal. There was no significant difference in CCT measurements between replicates performed by the same operator for each modality. The coefficient of variation within and between imaging modalities was low (range 0.63–2.5%). The intraclass correlation coefficient comparing methods was 0.92. Conclusions Correlation between modalities was excellent; however, ultrasonic pachymetry set at a standard velocity of 1636 m/s overestimates CCT as compared to OCT.
Stress and burnout in policing: does military experience matter?

Purpose – Expanding on earlier research, this paper aims to develop a more complete understanding of military experience as it relates to stress and burnout in law enforcement. The current study examines whether influences on stress and burnout vary between officers with military experience and officers without a military background.Design/methodology/approach – Data for this study were obtained from earlier research on police staff at a Northeastern metropolitan city. A combination of analytic methods, including t‐tests and multivariate regression analysis, were used to explore the effects of variables on stress and burnout among military and non‐military officers.Findings – The results indicate that negative exposures to demanding events influenced burnout for all officers. In contrast, negative exposures affected stress levels for those officers with no military experience. Coping techniques were important predictors of stress and burnout for both groups; however, contrary to expectations, police exper...
Row Reducing Quantum Matrices, the Quantum Determinant, and the Dieudonné Determinant

Abstract We prove that row reducing a quantum matrix yields another quantum matrix for the same parameter q . This means that the elements of the new matrix satisfy the same relations as those of the original quantum matrix ring M q ( n ). As a corollary, we can prove that the image of the quantum determinant in the abelianization of the total ring of quotients of M q ( n ) is equal to the Dieudonne determinant of the quantum matrix. A similar result is proved for the multiparameter quantum determinant.
GABAergic but not anti-cholinergic agents re-induce clinical deficits after stroke.

Abstract Our goal was to determine whether the excitatory (i.e., GABA) neurotransmitter system was important in human stroke recovery. We hypothesized that giving midazolam, a GABAA agonist, to patients would re-induce clinical deficits to a greater extent than the anti-cholinergic scopolamine. Twelve patients (7 M) who had recovered from hemiparesis and/or aphasia after first-time stroke and 10 age-matched, healthy controls underwent double-blinded drug challenge with midazolam and 90 days later with scopolamine, or vice versa. Language was scored for comprehension, naming and repetition, and motor function was tested with the 9-Hole Peg Test (9HPT) in each hand. The drugs were administered intravenously in small aliquots until mild awake sedation was achieved. The primary outcome was the change scores from baseline to the two drug conditions, with higher scores denoting greater loss of function. Ten of the 12 patients had recovered from hemiparesis and 7 from aphasia. The median time from stroke to participation was 9.3 months (range = 0.3–77.9 months). For motor function, analysis of variance showed that change scores on the 9HPT were significantly greater in patients using the previously paretic hand during the drug state with midazolam (p = 0.001). Similarly, language change scores were significantly greater among recovered aphasics during the midazolam challenge (p = 0.01). In our study, patients demonstrated transient re-emergence of former stroke deficits during midazolam but not scopolamine. These data provide beginning clinical evidence for the specificity of GABA-sensitive pathways for stroke recovery.
Charmonium — In and out of the nucleus

Abstract The bound states of charm and anticharm quarks, charmonium, offer a unique opportunity to explore the relationship between the traditional way of understanding hadronic interactions in nuclear physics, i.e., in terms of meson exchanges, and the QCD based description in terms of gluon exchanges. Inserting charmonium, for example J ψ , into the nucleus leads to many interesting possibilities. Several of these are mentioned. One, namely J ψ attenuation in nuclei, is discussed in some detail because of its importance as the possible signature of quark-gluon plasma(QGP) formation in relativistic heavy ion collisions. A technique for the direct measurement of J ψ -nucleon cross section is proposed.
Optical Studies of Electronic Transitions in Hexa‐ and Tetracoordinated Mn2+ Crystals

The polarized absorption spectra of Mn2+ in (CH3)4NMnCl3 and [(CH3)4N]2MnCl4 have been studied at 298°, 77°, and 2°K. Marked optical anisotropy was observed in both complexes. Details of the spectra indicate that the surroundings of the hexacoordinated Mn2+ ion are trigonally distorted from octahedral symmetry. Unlike the chemically similar alkali metal manganese halides, (CH3)4NMnCl3 undergoes no paramagnetic—antiferromagnetic transition between 298° and ≈4°K. Abnormal intensities in the spectrum appear to be unrelated to exchange mechanisms. The surroundings of the tetracoordinated Mn2+ ion very nearly approximate tetrahedral symmetry. However, the true Cs site symmetry is evident in the very sharp line absorption near 23 000 cm−1. The polarization behavior of the ion in both coordinations is discussed qualitatively in terms of the selection rules for the appropriate double group. The green luminescence of the tetrahedral complex and the pink luminescence of the octahedral complex have also been measure...
REPRESENTING COBOL IN PROLOG—TOWARDS PROGRAM COMPREHENSION AND REENGINEERING

This paper sets out to investigate how COBOL programs can be interpreted using Prolog. For this purpose, we examine how an executable logic specification can be obtained, which is semantically equivalent to the original source. We define a specification language COPRA as a restricted subset of Prolog and show how various imperative constructs, such as GOTOs and subroutine calls, can be handled in this language. The specification is generated automatically and may serve as a starting point for reengineering in form of a higher-level modification of the source program.
Planetary-Scale Waves and the Cyclic Nature of Cloud Top Dynamics on Venus

Quantitative data on the properties of the planetary scale wave modes at the Venus cloud tops have been derived from eight years of Pioneer Venus UV images. At least four planetary-scale wave modes are established on this basis; it is suggested that all play an important role in the maintenance of the equatorial winds. The evidence obtained suggests that the equatorial dynamics of Venus is cyclic, with an apparent time-scale of 5-10 yr. The long-term evolution and maintenance of the Venus cloud-top superrotation reflects a complex balance among at least four eddy momentum transport equations.
A theory-based approach to thermal field-flow fractionation of polyacrylates

A theory-based approach is presented for the development of thermal field-flow fractionation (ThFFF) of polyacrylates. The use of ThFFF for polymer analysis has been limited by an incomplete understanding of the thermal diffusion which plays an important role in retention and separation. Hence, a tedious trial-and-error approach to method development has been the normal practice when analyzing new materials. In this work, thermal diffusion theories based on temperature dependent osmotic pressure gradient and polymer-solvent interaction parameters were used to estimate thermal diffusion coefficients (D(T)) and retention times (t(r)) for different polymer-solvent pairs. These calculations identified methyl ethyl ketone as a solvent that would cause significant retention of poly(n-butyl acrylate) (PBA) and poly(methyl acrylate) (PMA). Experiments confirmed retention of these two polymers that have not been previously analyzed by ThFFF. Theoretical and experimental D(T)s and t(r)s for PBA, PMA, and polystyrene in different solvents agreed to within 20% and demonstrate the feasibility of this theory-based approach.
Adenia barthelatii (Passifloraceae), a new endemic species of Mayotte and its phylogenetic status within the genus Adenia

Morphological characters support the description of a new species of Passifloraceae from Mayotte Island: Adenia barthelatii M. Pignal, Yockteng, Hearn & Labat. Morphological and molecular data suggest that A. barthelatii belongs to the ‘warty-gland’ subclade of Clade V defined by Hearn elsewhere. Since the warty-gland clade is restricted to the Malagasy region we suggest a Malagasy origin of this Maorian species of Adenia .
Shocks in the polar wind

The occurrence of shock waves in the terrestrial polar wind was predicted many years ago by a time-dependent three-dimensional model based on hydrodynamic equations. These shocks were seen to occur for counterstreaming ion populations and for cases when a convecting flux tube entered a region of sharply increasing electron temperature, such as the dayside cusp. Other studies conducted at about the same time showed that the shocks induced by counterstreaming ion populations may simply be artifacts of the adopted hydrodynamic model. The validity of shocks induced by electron temperature enhancements has remained an open question. Using a macroscopic particle-in-cell (PIC) code, we have verified the hydrodynamic prediction that sudden electron temperature enhancements can launch shock waves in a convecting flux tube of plasma. Our simulation follows a flux tube as it convects antisunward across the dayside auroral oval, the polar cap, and the nightside auroral oval. The electron temperature at 2000 km altitude is assumed to be relatively low (3000 K) in the subauroral ionosphere and in the polar cap but much higher (7000 K) in the dayside and nightside auroral oval. As the flux tube enters the auroral oval, either on the dayside or the nightside, forward and reverse shock pairs in the H+ component of the plasma are created at the bottom of the flux tube and propagate upward until they exit the simulation region at the top. The forward and reverse shock fronts propagate at speeds greater than and less than the drift speed of the H+ gas, respectively.
Reversal of the ritter reaction as observed under electron impact conditions

Fragmentations of various 2-phenethylamides, trifluoroacylimidates and imidoyl trifluoromethyl sulfonates have been studied and a pathway for the formation of retro-Ritter reaction products is proposed.
The sweetness and stereochemistry of l-aspartyl-fenchylaminoalcohol derivatives

Abstract Four fenchylaminoalcohols were derived from ( + )-fenchone in five steps. They were resolved with ( + )- and (−)-tartaric acid, then condensed with N-carbobenzoxy-L-aspartic acid β-benzylester followed by hydrogenolysis to give four L-aspartyl-fenchylaminoalcohols. By the evalution of their taste, only (2R,3R)-aminoalcohol showed potent sweetness.
Multidimensional Raman Spectroscopic Signatures as a Tool for Forensic Identification of Body Fluid Traces: A Review

The analysis of body fluid traces during forensic investigations is a critical step in determining the key details of a crime. Several confirmatory and presumptive biochemical tests are currently utilized. However, these tests are all destructive, and no single method can be used to analyze all body fluids. This review outlines recent progress in the development of a novel universal approach for the nondestructive, confirmatory identification of body fluid traces using Raman spectroscopy. The method is based on the use of multidimensional spectroscopic signatures of body fluids and accounts for the intrinsic heterogeneity of dry traces and donor variation. The results presented here demonstrate that Raman spectroscopy has potential for identifying traces of semen, blood, saliva, sweat, and vaginal fluid with high confidence.
Profile of autoantibody to basement membrane zone proteins in patients with mucous membrane pemphigoid: long-term follow up and influence of therapy

Mucous membrane pemphigoid (MMP) is an autoimmune mucocutaneous blistering disease characterized by autoantibodies to components within the basement membrane zone. In this study, we report the titers of autoantibodies to antigens in the BMZ, in the sera of 13 patients, treated with intravenous immunoglobulin as monotherapy over a consecutive 18-month period. Using bovine gingiva lysate as substrate in an immunoblot assay, autoantibodies to human bullous pemphigoid antigens (BPAg1 and BPAg2), human beta4 integrin, and laminin 5 were measured. A statistically significant (P < 0.05) decline in the autoantibody titers to beta4-integrin was observed after 3.42 months of initiating the IVIg therapy. These titers were undetectable after 13 months of therapy. The titers of antibodies to BPAg1 and BPAg2 did not correlate with disease activity or response to therapy. Antibodies to laminins were not detected. In patients with MMP, autoantibody titers to beta4-integrin correlate with disease activity and response to therapy.
In vitro and in vivo evaluations of increased effective beam width for heat deposition using a split focus high intensity ultrasound (HIFU) transducer.

Purpose: To develop a novel and efficient, in vitro method for characterizing temporal and spatial heat generation of focused ultrasound exposures, and evaluate this method to compare a split focus and conventional single focus high intensity focused ultrasound transducer.Materials and methods: A HIFU tissue-mimicking phantom was validated by comparing respective temperature elevations generated in the phantoms and in murine tumors in vivo. The phantom was then used in combination with IR thermography to spatially and temporally characterize differences in low-level temperature elevation (e.g. 3–5°C) produced by a single focus and split focus HIFU transducer, where the latter produces four simultaneous foci. In vivo experiments with heat sensitive liposomes containing doxorubicin were then carried out to determine if the larger beam width of the split focus transducer, compared to the single focus, could increase overall deployment of the drug from the liposome.Results: Temperature elevations generated in...
Achieving antigen-specific immune regulation

A study in this issue of the JCI shows that in response to autoantigens consisting of peptides from normal proteins, patients with diabetes mount a T cell response characterized by production of IFN-gamma (see the related article beginning on page 451). However, in response to these same antigens, T cells from normal control subjects produce IL-10. The antigen-specific response characterized by release of a regulatory cytokine suggests a mechanism for the control of autoimmunity that is initiated at the time of antigen presentation.
Plenty of Sickness : Descriptions by African Americans living in rural areas with type 2 diabetes

PurposeThe purposes of this study were to (1) describe facilitators and barriers to self-care for African Americans with type 2 diabetes living in a rural community, (2) compare experiences of men ...
Serum lipids during the first year following acute spinal cord injury

Patients with chronic spinal cord injury (SCI) have low levels of high-density lipoprotein (HDL) cholesterol. The cause of this abnormality and its relation to SCI are unknown. We studied 100 consecutively admitted males with acute SCI prospectively for 1 year to determine changes in serum lipids following acute SCI and the relation of these changes to the level of injury and physical activity. Low-density lipoprotein (LDL), HDL, and total cholesterol and triglycerides were all decreased following acute SCI and gradually increased toward normal by 1 year. Serum HDL, LDL, and total cholesterol levels correlated with the level of SCI: levels were lower in quadriplegic compared with paraplegic patients. Serum HDL showed the greatest change following SCI, increasing by 26% in quadriplegic and 18% in paraplegic patients. These changes in serum lipid levels could not be explained by changes in alcohol consumption or body weight. We estimated that only 44% of the increase in HDL following SCI was associated with an increase in physical activity. We postulate that interruption of the autonomic nervous system influences lipid metabolism and serum lipid levels.
Comparative study of electrophoretic and rapid chroma-tographic methods for separation of lactic dehydrogenase isoenzymes

Abstract This investigation was designed to evaluate the agarose gel electrophoretic procedure and Sephadex DEAE batch Chromatographic technic for separation of lactic dehydrogenase isoenzymes. The former method is somewhat time-consuming and requires exacting technic while the batch Chromatographic procedure is relatively simple and rapid. Our experience indicates that agarose gel electrophoresis should be the method of choice in the clinical laboratory.
The upgraded IPNS single crystal diffractometer

Abstract The IPNS single crystal diffractometer (SCD) has been operating since 1981 primarily as a general purpose instrument for small molecule crystallography and for surveying reciprocal space. The instrument has recently undergone a major upgrade involving replacement of most of the hardware and software. In particular, two new position-sensitive scintillator area detectors based on the Anger camera concept were designed, fabricated and installed on the SCD. Each of these detectors have active areas of 15×15 cm 2 with a spatial resolution of better than 2 mm. A new data acquisition system permits the use of larger data files with a larger wavelength bandwidth at higher time-of-flight resolution. Software developed with tools in the ISAW workbench provides graphical manipulation of three-dimensional arrays of data in histogram coordinates and in reciprocal space, and user-friendly wizards for routine data analysis. As described in this paper, the upgrade of the SCD provides significant improvements in resolution, speed of data collection, and ease of use.
Cardiopulmonary pharmacology of enkephalins in the conscious dog.

Various enkeplalins (ENK) have been reported to alter heart rate, systemic blood pressure, and respiratory function but with variable results. We previously found that pentobarbital anesthesia reversed the increases in heart rate and systemic arterial blood pressure produced by Leu 5 -ENK in the dog. We have now studied the cardiopulmonry responses to systemically injected enkephalins in the awake, chronically instrumented dog. In these unanesthetized dogs, Leu 5 -ENK, Met 5 -ENK, and an ENK dimer increased heart rate, systemic aterial pressure, and respiratory rate in a dose-dependent fashion. D-Phe 4 , Met 5 -ENK, an analog with behavioral activity but without analgesic or in vitro opiate effects, was inactive. Leu 5 -ENK was studied in detail; typically, heart rate and systemic pressure increased within 20 sec and returned to baseline in less than 180 sec. Intra-arterial injections produced a smaller increase in heart rate than did intravenous injections, but similar increases in systemic arterial blood pressure were recorded. These cardiovascular responses suggest that sysrtemically injected enkephalins suppress baroreceptor reflexes and may have a role in cardiopulmonary regulation.
Media use and public confidence in democratic institutions

Content analyses have documented media negativity toward democratic institutions, and survey data have confirmed increasingly negative perceptions of these institutions. This study examines the impact of various media on confidence in democratic institutions — the Office of the Presidency, Congress, the criminal court system, the news media, the police, and the public school system. After accounting for the impact of respondent demographics, knowledge (expertise), and political partisanship, the results revealed limited influence of media use on perceptions of these institutions. Contrary to expectations, television news viewing predicted positively to perceptions of the news media and public schools, and newspaper reading was associated with favorable evaluations of the criminal court system and schools. Significant interaction effects were found for the news media and public schools, with listening to political talk radio eliciting lower levels of confidence among stronger Republican partisans. The only...
A Person-Centered Approach to Multicultural Counseling Competence

This article examines current and historical trends in psychotherapy research and practice with racial/ethnic minority populations. Initially, research on Derald Sue’s multicultural counseling competencies is provided as a foundation to further examine the evidence regarding effective cultural adaptations to mainstream treatment approaches, such as cognitive-behavior therapy and interpersonal psychotherapy. Next, a brief outline of Carl Rogers’s psychotherapy research tradition is presented, with a focus on both past and present evidence suggesting that person-centered therapy may be effective across diagnoses, as well as cultures. Using psychotherapy evidence from both the latter half of the 20th century and the initial decades of the 21st century, cultural adaptations to previously hypothesized person-centered therapy mechanisms of change are proposed. In particular, this culturally adapted person-centered approach is suggested to provide a competent and effective treatment system for racial/ethnic mino...
Digitalis: is it useful in congestive heart failure in patients in normal sinus rhythm?

The value of digoxin in the patient in normal sinus rhythm with chronic congestive heart failure continues to be controversial. Although many patients taking digoxin have no clinical deterioration aft
Role of Vortices in Growth of Microbubbles at Mitral Mechanical Heart Valve Closure

This study is aimed at refining our understanding of the role of vortex formation at mitral mechanical heart valve (MHV) closure and its association with the high intensity transient signals (HITS) seen in echocardiographic studies with MHV recipients. Previously reported numerical results described a twofold process leading to formation of gas-filled microbubbles in-vitro: (1) nucleation and (2) growth of micron size bubbles. The growth itself consists of two processes: (a) diffusion and (b) sudden pressure drop due to valve closure. The role of diffusion has already been shown to govern the initial growth of nuclei. Pressure drop at mitral MHV closure may be attributed to other phenomena such as squeezed flow, water hammer and primarily, vortex cavitation. Mathematical analysis of vortex formation at mitral MHV closure revealed that a closing velocity of approximately 12 m/s can induce a strong regurgitant vortex which in return can instigate a local pressure drop of about 0.9 atm. A 2D experimental model of regurgitant flows was used to substantiate the impact of vortices. At simulated flow and pressure conditions, a regurgitant vortex was observed to drastically enlarge micron size hydrogen bubbles at its core.
Anisotropic electrical behavior of the blue potassium molybdenum bronze, K0·30MoO3

Abstract Cleavable platelets of the blue potassium molybdenum bronze, K 0·30 MoO 3 , were prepared by the electrolysis of mixtures of potassium molybdate and molybdenum (VI) oxide. X-ray diffraction studies were performed in order to relate the morphological habit of these crystals to the actual crystal structure. Results of the X-ray study and considerations of crystal structure motivated an investigation of the electrical resistivity along certain significant crystallographic directions. An anisotropy in the electrical resistivity of approximately 1-1/2-2 orders of magnitude was observed throughout the temperature range 80°–340°K. In addition, a change from semiconducting to metallic behavior, which occurs at approximately 180°K, was also sensitive to sample orientation.
Vigilance and predator detection vary between avian species with different visual acuity and coverage

Interspecific variations in avian visual systems have been suggested to influence antipredator strategies, yet little empirical evidence exists on how morphological and ecological factors associated with visual properties can constraint predator detection. We investigated antipredator responses (predator detection probabilities and vigilance behavior) in 2 species with different visual properties (European starlings, Sturus vulgaris, have higher acuity and wider blind areas at the rear of their heads than house sparrows, Passer domesticus) in relation to distance to the predator, body posture, and head orientation. Visual acuity may affect the distance at which a predator is detected; while the size of the blind area may influence the body postures and head orientation with the highest predator detection probabilities. Distance to the decreased predator detection probabilities of house sparrows (lower acuity) but not those of European starlings. Certain body postures and head orientations, influenced both species despite the interspecific differences in visual field configuration. Times allocated to scanning were similar, but European starlings had longer head-up scan bouts likely to enhance scanning coverage, whereas house sparrows had higher head-up scan rates probably to reduce the length of interscan intervals. We discuss alternative interpretations; however, our findings suggest that sensory configurations may limit the effectiveness of some antipredator strategies under certain ecological conditions, which has implications for understanding the evolution of different behavioral mechanisms that reduce predation risk. Key words: predator detection, vigilance, visual acuity, visual ecology, visual fields. [Behav Ecol]
Hepatitis B and Hepatitis C Virus Replication Upregulates Serine Protease Inhibitor Kazal, Resulting in Cellular Resistance to Serine Protease-Dependent Apoptosis

Hepatitis B and C viruses (HBV and HCV, respectively) are different and distinct viruses, but there are striking similarities in their disease potential. Infection by either virus can cause chronic hepatitis, liver cirrhosis, and ultimately, liver cancer, despite the fact that no pathogenetic mechanisms are known which are shared by the two viruses. Our recent studies have suggested that replication of either of these viruses upregulates a cellular protein called serine protease inhibitor Kazal (SPIK). Furthermore, the data have shown that cells containing HBV and HCV are more resistant to serine protease-dependent apoptotic death. Since our previous studies have shown that SPIK is an inhibitor of serine protease-dependent apoptosis, it is hypothesized that the upregulation of SPIK caused by HBV and HCV replication leads to cell resistance to apoptosis. The evasion of apoptotic death by infected cells results in persistent viral replication and constant liver inflammation, which leads to gradual accumulation of genetic changes and eventual development of cancer. These findings suggest a possibility by which HBV and HCV, two very different viruses, can share a common mechanism in provoking liver disease and cancer.
Ethnicity and long-term outcome after an acute coronary event ☆ ☆☆ ★ ★★

Abstract Background The role of ethnicity on the long-term outcome after myocardial infarction is not fully understood. Methods and Results We analyzed the data from the Multicenter Study of Myocardial Ischemia in North America and Japan. We enrolled patients after acute myocardial infarction (MI) or unstable angina, with follow-up for 6 to 43 months, an average of 26 months. Among patients enrolled, there were 627 white, 158 black, and 109 Asian patients. Unadjusted cardiac events (cardiac death or nonfatal MI) were more frequent in black patients than in the other 2 ethnic groups (12% in blacks, 6.4% in whites, 4.0% in Asians, P = .022). Although insulin-dependent diabetes, history of hypertension, and female sex were most frequent in black subjects, coronary angioplasty and thrombolysis at index event were done equally. After adjusting for several covariates, Cox analyses revealed that the black group was significantly associated with cardiac events (hazard ratio 6.5, P = .002). Subgroup analyses showed that the event rate among patients who had a higher educational level (6.1% in whites, 5.9% in blacks, and 7.0% in Asian, P = .94) or who were in a professional occupational class (5.7% in whites, 4.0% in blacks, and 4.8% in Asians, P = 1.0) was not different among the 3 ethnic groups. Conclusions Blacks have an increased rate of cardiac events after MI, and a lower socioeconomic status may contribute to the adverse outcome in this ethnic group. (Am Heart J 1999;138:500-6.)
Isolation and characterization of a xanthophyll-rich fraction from the thylakoid membrane of Dunaliella salina(green algae).

Long-term acclimation to irradiance stress (HL) of the green alga Dunaliella salina Teod. (UTEX 1644) entails substantial accumulation of zeaxanthin along with a lowering in the relative amount of other pigments, including chlorophylls and several carotenoids. This phenomenon was investigated with wild type and the zea1 mutant of D. salina, grown under conditions of low irradiance (LL), or upon acclimation to irradiance stress (HL). In the wild type, the zeaxanthin to chlorophyll (Zea/Chl) (mol : mol) ratio was as low as 0.009 : 1 under LL and as high as 0.8 : 1 under HL conditions. In the zea1 mutant, which constitutively accumulates zeaxanthin and lacks antheraxanthin, violaxanthin and neoxanthin, the Zea/Chl ratio was 0.15 : 1 in LL and 0.57 : 1 in HL. The divergent Zea/Chl ratios were reflected in the coloration of the cells, which were green under LL and yellow under HL. In LL-grown cells, all carotenoids occurred in structural association with the Chl-protein complexes. This was clearly not the case in the HL-acclimated cells. A β-carotene-rich fraction occurred as loosely bound to the thylakoid membrane and was readily isolated by flotation following mechanical disruption of D. salina. A zeaxanthin-rich fraction was specifically isolated, upon mild surfactant treatment and differential centrifugation, from the thylakoid membrane of either HL wild type or HL-zea1 mutant. Such differential extraction of β-carotene and Zea, and their separation from the Chl-proteins, could not be obtained from the LL-grown wild type, although small amounts of Zea could still be differentially extracted from the LL-grown zea1 strain. It is concluded that, in LL-grown D. salina, xanthophylls (including most of Zea in the zea1 strain) are structurally associated with and stabilized by the Chl-proteins in the thylakoid membrane. Under HL-growth conditions, however, zeaxanthin appears to be embedded in the lipid bilayer, or in a domain of the chloroplast thylakoids that can easily be separated from the Chl-proteins upon mild surfactant treatment. In conclusion, this work provides biochemical evidence for the domain localization of accumulated zeaxanthin under irradiance-stress conditions in green algae, and establishes protocols for the differential extraction of this high-value pigment from the green alga D. salina.
Spatial-spectral 3D imaging system using broadband sources

In this paper we review volume holographic imaging techniques for 3D imaging. Our investigation focuses on holographic imaging systems that operate with broadband illuminator sources. This type of imaging system has the advantage of reducing or eliminating the need for scanning along lateral or axial direction. However, the utilization of broadband illuminator source produces significant reduction in depth resolution. Modeling and experiments are presented to describe the dependence of lateral and depth resolution on the hologram parameters.
Viral infection and aging as cofactors for the development of pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a disease of unknown origin and progression that primarily affects older adults. Accumulating clinical and experimental evidence suggests that viral infections may play a role, either as agents that predispose the lung to fibrosis or exacerbate existing fibrosis. In particular, herpesviruses have been linked with IPF. This article summarizes the evidence for and against viral cofactors in IPF pathogenesis. In addition, we review mechanistic studies in animal models that highlight the fibrotic potential of viral infection, and explore the different mechanisms that might be responsible. We also review early evidence to suggest that the aged lung may be particularly susceptible to viral-induced fibrosis and make recommendations for future research directions.
Nutrient Limitation of the Macroalga, Penicillus capitatus, Associated with Subtropical Seagrass Meadows in Bermuda

Nutrient limitation of the rhizophytic macroalga Penicillus capitatus found associated with sub- tropical seagrass meadows in Bermuda was determined from enrichment assays and subsequent tissue analyses. The photosynthetic response of P. capitatus to additions of inorganic nitrogen (N) or phosphorus (P), measured as oxygen evolution in closed incubation chambers, increased significantly in both the 16 h and 6 d experiments only with nitrogen enrichment. The average photosynthetic response for all treatments was virtually identical in the two experiments, indicating that there was not a significant time lag in nutrient uptake and that the short term (16 h) assay accurately reflected the longer term (6 d) photosynthetic response to nutrient enrichment. Average tissue nitrogen levels for the nitrogen-treated algae were 29% higher than the phosphorus-treated algae and 18% greater than the controls, corroborating the results from the photosynthesis assay. P. capitatus may acquire nutrients directly from sediment sources via rhizoid holdfasts. Ratios of total dissolved nitrogen (TN) to total dissolved phosphorus (TP) in pore water at 10 and 20 cm depths (6.1 and 4.5, respectively) indicate a nitrogen-limited nutrient pool. These low pore water TN:TP ratios may be a function of a limited sorptive capacity of the calcium carbonate sediments for phosphate, anthropogenic nutrient inputs, or high rates of denitrification, all of which would induce N rather than P limitation in these carbonate-rich sediments.
Monte Carlo modeling of photon transport in buried bone tissue layer for quantitative Raman spectroscopy

Light-scattering spectroscopy has the potential to provide information about bone composition via a fiber-optic probe placed on the skin. In order to design efficient probes, one must understand the effect of all tissue layers on photon transport. To quantitatively understand the effect of overlying tissue layers on the detected bone Raman signal, a layered Monte Carlo model was modified for Raman scattering. The model incorporated the absorption and scattering properties of three overlying tissue layers (dermis, subdermis, muscle), as well as the underlying bone tissue. The attenuation of the collected bone Raman signal, predominantly due to elastic light scattering in the overlying tissue layers, affected the carbonate/phosphate (C/P) ratio by increasing the standard deviation of the computational result. Furthermore, the mean C/P ratio varied when the relative thicknesses of the layers were varied and the elastic scattering coefficient at the Raman scattering wavelength of carbonate was modeled to be different from that at the Raman scattering wavelength of phosphate. These results represent the first portion of a computational study designed to predict optimal probe geometry and help to analyze detected signal for Raman scattering experiments involving bone.