cssi/SciSciGPT-SciSciNet huggingface dataset:
A method for assessing the effectiveness of anti-vibration gloves using biodynamic responses of the hand arm system

Abstract Anti-vibration gloves are widely used to help minimize hand–arm vibration exposure. In this study, an alternative method is proposed to assess the vibration isolation effectiveness of these gloves using the biodynamic responses of the bare- and gloved-hand–arm system exposed to vibration. The laboratory experiments were performed with a total of five human subjects using a typical anti-vibration air bladder glove subjected to a broad-band random vibration spectrum in conjunction with a specially designed instrumented handle. The measured data were analyzed to derive the biodynamic responses of the bare as well as gloved human hand–arm system in terms of the apparent mass and the mechanical impedance. The two biodynamic responses were applied to estimate the vibration isolation effectiveness of the glove. The validity of the proposed concept was examined by comparing the estimated vibration transmissibility magnitudes of the glove with those obtained using a palm adapter method. The comparison of the results suggests that the proposed method offers a good alternative for estimating glove vibration transmissibility. The measured data and the proposed method based upon the biodynamic responses were further used to investigate the effect of the palm adapter on the vibration transmissibility of the glove. The results suggest that the presence of the palm adapter between the subject's palm and the glove may not alter the basic trends in the transmissibility response, but it would affect the transmissibility magnitudes in the middle- and high-frequency ranges. A distinct advantage of the proposed method is that it eliminates the use of an adapter in assessing the vibration isolation effectiveness of the gloves.
The Determination of the Age of Iron and Stony Meteorites from their Radioactivity

Observed meteor and meteorite velocities (Opik, Boothroyd) indicate that a small fraction, perhaps in the neighborhood of 15 percent, of all meteorites striking the earth are of extra-solar origin. Helium-radium age measurements (Paneth, Urry, & Koeck) on 23 iron meteorites, none of which was of known heliocentric velocity, disclose a uniform distribution of last-solidification ages with no ages clearly greater than the age of the earth. Thus, either the specimens are all from the solar system, as Paneth proposed, or the galactic system is of the same age as the earth. Two critical experiments are in progress, based on the following evidence. The abundance-ratio of the C, O, Si, Cl, Fe, Co, and Ni isotopes in meteorites has been studied by various workers, and is found to be the same as in the terrestrial elements. Moreover, the ratio of the two independent isotopes of uranium, 92U235 and 92U238, is the same in all terrestrial specimens, regardless of the geologic age of the mineral in which they are found. It is therefore taken as a reasonable premise, but regarded as a working assumption only, that the original isotopic ratio of any element is a constant of nature and is independent of its place of origin in the galactic system. Measurements of the actinouranium vs. uranium I activity-ratio, and of the specific activity of potassium, are in progress on stony meteorites selected for their known heliocentric velocities. Some of these are of extra-solar origin while others are solar-system meteorites. The final results of the analyses give the difference between the age of the atoms in the meteorites and the same type of atoms in the earth. The method is independent of all influence from varying chemical and physical conditions during the history of the meteorite, as it deals entirely with isotopic ratios. The study of both the AcU, UI ratio and the K40, K41 ratio provides an independent check on the basic assumption of the method. The apparatus, technique, and mathematical background for these experiments are fully described. The announcement of the numerical results of these analyses is deferred until all the observations and control runs have been repeated many times, in order to assure their complete reliability.
Characterization of the lysyl adducts formed from prostaglandin H2 via the levuglandin pathway.

Prostaglandin H2 has been demonstrated to rearrange to γ-ketoaldehyde prostanoids termed levuglandins E2 and D2. As γ-dicarbonyl molecules, the levuglandins react readily with amines. We sought to characterize the adducts formed by synthetic levuglandin E2 and prostaglandin H2-derived levuglandins with lysine. Using liquid chromatography/electrospray mass spectrometry, we found that the reaction predominantly produces lysyl-levuglandin Schiff base adducts that readily dehydrate to form lysyl-anhydrolevuglandin Schiff base adducts. These adducts were characterized by examination of their mass spectra, by analysis of the products of their reaction with sodium cyanide, sodium borohydride, and methoxylamine and by the mass spectra derived from collision-induced dissociation in tandem mass spectrometry. The Schiff base adducts also are formed on peptide-bound lysyl residues. In addition, synthetic levuglandin E2 and prostaglandin H2-derived levuglandins produced pyrrole-derived lactam and hydroxylactam adducts...
Receptor-effector coupling by G proteins: implications for normal and abnormal signal transduction.

I. Introduction THE ROLE of heterotrimeric guanine nucleotide binding proteins (G proteins) in signal transduction was first covered in Endocrine Reviews in 1981, when three distinct G proteins involved in visual transduction and regulation of cAMP formation were recognized (1). This topic was updated in Endocrine Reviews in 1989 by which time the number of mammalian G proteins identified had doubled, and their roles in regulation of various phospholipases and ion channels had been recognized (2). Barely 3 years later, the number of distinct mammalian G proteins recognized has again doubled, multiple G proteins have been identified in invertebrates, plants, and single-celled eukaryotes, and the number of cellular functions shown to be regulated by G proteins has increased correspondingly. Numerous excellent reviews covering various aspects of this topic have recently appeared (3–9), but given the rapidity of progress in this field, an update in Endocrine Reviews appears timely. This review summarizes rece...
Molecular dynamics simulations of rubredoxin from Clostridium pasteurianum: changes in structure and electrostatic potential during redox reactions.

Molecular dynamics simulations of Clostridium pasteurianum rubredoxin in the oxidized and reduced forms have been performed. Good agreement between both forms and crystal data has been obtained (rms deviation of backbone atoms of 1.06 and 1.42 A, respectively), which was due in part to the use of explicit solvent and counterions. The reduced form exhibits an unexpected structural change: the redox site becomes much more solvent-accessible, so that water enters a channel between the surface and the site, but with little actual structural rearrangement (the rms deviation of backbone atoms between the oxidized and reduced is 0.77 A). The increase in solvent accessibility is also seen, although to a much lesser extent, between the oxidized and reduced crystal structures of Pyrococcus furiosus rubredoxin, but no high resolution crystal or nuclear magnetic resonance solution data exist for reduced C. pasteurianum rubredoxin. The electrostatic potential at the iron site and fluctuations in the potential, which contribute to both the redox and electron transfer properties, have also been evaluated for both the oxidized and the reduced simulations. These results show that the backbone plays a significant role (62–70 kcall/mol/e) and the polar sidechains contribute relatively little (0–4 kcal/mol/e) to the absolute electrostatic potential at the iron of rubredoxin for both forms. However, both groups contribute significantly to the change in redox state by becoming more polarized and more densely packed around the redox site upon reduction. Furthermore, these results show that the solvent becomes much more polarized in the reduced form than in the oxidized form, even excluding the penetrating water. Finally, the simulation indicates that the contribution of the charged side chains to the electrostatic potential is largely canceled by that of the counterions. © 1995 Wiley-Liss, Inc.
Characterization of the guanosine-3'-diphosphate-5'-diphosphate binding site on E. coli RNA polymerase using a photoprobe, 8-azidoguanosine-3'-5'-bisphosphate.

Abstract Nucleotide binding sites on DNA-dependent RNA polymerase from E. coli have been studied by photoaffinity labeling with a GTP analog [γ-32P]-8-AzidoGTP and a guanosine-3′-diphosphate-5′-diphosphate analog, 8-Azidoguanosine-3′-phosphate-5′-[5′-32P]phosphate. The guanosine diphosphate photoprobe labeled the β, β′, and δ subunits with the δ subunit being most heavily labeled. The GTP photoprobe also labeled the β, β′, δ subunits but the β′ subunit was most heavily labeled. In competition experiments guanosine-3′-diphosphate-5′-diphosphate decreased photolabeling by 8-Azidoguanosine-3′-phosphate-5′-[5′-32P]phosphate better than GTP, while the opposite was true for photolabeling with [γ-32P]8-AzidoGTP. The guanosine diphosphate photoprobe inhibited transcription on E. coli DNA with Ki of ca. 150 μM. Present studies suggest a unique ppGpp binding site distinct from substrate binding site(s) and this photoprobe may be used to localize this binding site(s).
Bupivacaine, but not lidocaine, disrupts cardiolipin-containing small biomimetic unilamellar liposomes.

Inadvertent intravenous administration of bupivacaine, unlike that of lidocaine, is associated with significant cardiotoxicity. However, the mechanism(s) underlying this phenomenon is uncertain. High concentrations of cardiolipin, an anionic phospholipid, are found in the mitochondria membrane of cardiomyocytes. We hypothesized that bupivacaine, but not lidocaine, interacts avidly with cardiolipin in the mitochondria membrane of cardiomyocytes and alters its integrity thereby accounting, in part, for cardiotoxicity. Accordingly, the purpose of this study was to begin to address this issue by determining the effects of bupivacaine and lidocaine on permeability of cardiolipin-containing biomimetic small unilamellar liposomes. We found that bupivacaine, but not lidocaine, elicited a significant, concentration-dependent increase in carboxyfluorescein release from cardiolipin-containing small unilamellar liposomes (size, 165 nm) composed of egg yolk phosphatidylcholine and cholesterol (p 0.5). Collectively, these data indicate that bupivacaine, but not lidocaine, interacts avidly and selectively with biomimetic small unilamellar liposomes containing cardiolipin and disrupts their integrity. We suggest that these interactions underlie, in part, bupivacaine-induced cardiotoxicity.
Incorporating Procedural Information in a Paired Approach Task

This study focused on pilot performance at simultaneously flying simulated instrument approaches and self-separating from an aircraft on approach to a closely spaced parallel runway. The participant pilots flew approaches on Georgia Tech's Reconfigurable Flight Simulator and were instructed to remain within the “safe zone” - an area in which the subject aircraft was safe from collision danger and wake vortices from the other aircraft as depicted on their navigation display. Two underlying bases for calculating the safe zone were used: a “predicted” safe zone utilizing procedural information, and an “actual” safe zone utilizing real-time information. No display effects were found for pilot performance or behavior, despite the very different implications of the two safe zone depictions. Also, pilots monitored the other aircraft closely for compliance, but could not recognize the implications of noncompliance for their own approach. This suggests that pilots have a particular, persistent, and perhaps poor, s...
The Global Age: From a Sceptical South to a Fearful North

This chapter discusses the central observation and the organising principle of the analysis: the irony of the role reversal that has occurred between the developing and the developed economies on fears of integration into the global economy. It highlights that the fears of the developed countries are heavily, and destructively, focused on integration with the developing countries, just as the fears of the developing countries in the postwar decades were focused symmetrically on the imagined dangers of integrating with the developed countries. The chapter argues that the fears are, at best, exaggerated and, at worst, ill-informed, and suggests that the current, fear-fed demands in the major developed countries for changes in the rules and regimes that govern the world economy are much too often ill-designed. The dominant feature of the world economy is its increasing globalisation and the growing fear of its consequences in the developed countries.
Multiple sclerosis: oligoclonal bands still yield clues about multiple sclerosis.

Oligoclonal bands are present in the cerebrospinal fluid of most patients with multiple sclerosis (MS) and represent a useful diagnostic measure. Two recent studies indicate that the identification of such bands might provide insight into the underlying mechanism of disease in MS and guide the treatment of individuals with this disorder.
TU-E-202-01: Applying Baldrige National Program Methodology to Achieve Medical Physics Performance Excellence

The Malcolm Baldrige National Quality Improvement Act was signed into law in 1987 to advance U.S. business competitiveness and economic growth. Administered by the National Institute of Standards and Technology (NIST), the Act created the Baldrige National Quality Program (BNQP), which recognizes outstanding organizational performance with Baldrige Awards presented annually by the President of the United States at a public ceremony. At first directed only toward commercial organizations, award categories for health care, education and non‐profit organizations were later added. The comprehensive analytical approaches recommended by BNQP are well‐suited for the evaluation and sustainable improvement of medical physics program management and operations. In this Workshop, we describe how the Baldrige approach can facilitate medical physics performance enhancement in an increasingly complex and competitive healthcare environment. Team‐based self‐assessment is used for program evaluation and development to generate a profile of strengths and opportunities for improvement relative to outcome‐oriented goals. This methodology provides for an ordered examination of internal operations and trends and an objective means of benchmarking performance against guidelines published by professional organizations and regulatory agencies.
Clostridium difficile-associated disease in patients in a small rural hospital.

objective. To determine the risk factors for Clostridium difficile–associated disease (CDAD) in a 25-bed rural hospital and to compare antimicrobial use ratios at the study hospital with those at a large academic medical center. design. Case-control study. setting. A 25-bed rural hospital in Iowa during the period from August 2002 through January 2005. patients. A total of 17 case patients with CDAD and 34 control patients matched for age (ie, within 10 years of the case patient’s age), sex, and admission date (ie, within 2 weeks of the case patient’s admission date). methods. Retrospective medical record review was performed to obtain data on antimicrobial exposures during the 6 weeks before hospital admission for both case and control patients. Exact conditional logistic regression was used for univariable and multivariable analyses. Antimicrobial use ratios were calculated to compare the rates of antimicrobial use for case and control patients at the study hospital with the rates for patients evaluated in a study of CDAD at a nearly 700-bed teaching hospital. results. Case patients had a larger cumulative number of days of antimicrobial use ( ), and they received a larger total number P p .004 of antimicrobial agents during hospitalization ( ). Antimicrobial use ratios were higher for both case and control patients at the P p .001 smaller hospital, compared with the larger hospital. conclusions. CDAD at a small rural hospital was not associated with exposure to the antimicrobial classes that are typically associated with CDAD, but was instead related to the total number of antimicrobials used to treat patients. The rate of antimicrobial use for case and control patients was about 40% higher at the small rural hospital, compared with the corresponding rates at a large academic medical center. Infect Control Hosp Epidemiol 2007; 28:1236-1239
Polarized MODTRAN 3.7 applied to characterization of ocean color in the presence of aerosols

The color of the ocean and estuarine waters are key indicators of pollutants as well as biological phenomenon. However atmospheric aerosols can be produce a significant bias in the observations. Of particular importance is dust from the Sahara and Gobi Deserts on the Atlantic and Pacific Ocean photometric observations. Polarization can be used to deconvolute the effects of aerosols. In comparison to non- absorbing aerosols, the desert aerosol has opposite behavior for epsilon function with wavelength. Results show the degree of plane polarization decreases with the increase of the aerosol optical thickness and is wavelength dependent. The degree of polarization increases as the viewing zenith angle increase. An additional fallout of this analysis is the effect of aerosols on the ocean heat exchange; warming or cooling can occur depending upon the optical properties of the aerosols. Further, the visibility of military targets is strongly a function of aerosol scattering properties.
Convective heat transfer in an internally heated horizontal fluid layer with unequal boundary temperatures

Abstract An experimental investigation was conducted on the steady-state convective heat transfer in a horizontal water layer with isothermal, horizontal boundaries at unequal temperatures. Joule heating provided a uniform heat source throughout the fluid layer. Heat flux through each horizontal boundary was determined from the measured temperature drop across a plate of known thickness and thermal conductivity. The results were correlated by expressing the fraction of internally generated heat transferred downward as an explicit function of internal and external Rayleigh numbers.
Risk factors of deep infection in operatively treated pilon fractures (AO/OTA: 43)

Background/Aims The purpose of this study is to evaluate risk factors of deep infection following pilon fractures.
Protein kinase Cα mediates feedback inhibition of EGF receptor transactivation induced by Gq-coupled receptor agonists

Abstract While a great deal of attention has been focused on G-protein-coupled receptor (GPCR)-induced epidermal growth factor receptor (EGFR) transactivation, it has been known for many years that the tyrosine kinase activity of the EGFR is inhibited in cells treated with tumor-promoting phorbol esters, a process termed EGFR transmodulation. Because many GPCR agonists that elicit EGFR transactivation also stimulate the G q /phospholipase C (PLC)/protein kinase C (PKC) pathway, we hypothesized that PKC-mediated inhibition of EGFR transactivation operates physiologically as a feedback loop that regulates the intensity and/or duration of GPCR-elicited EGFR transactivation. In support of this hypothesis, we found that treatment of intestinal epithelial IEC-18 cells with the PKC inhibitors GF 109203X or Ro 31-8220 or chronic exposure of these cells to phorbol-12,13-dibutyrate (PDB) to downregulate PKCs, markedly enhanced the increase in EGFR tyrosine phosphorylation induced by angiotensin II or vasopressin in these cells. Similarly, PKC inhibition enhanced EGFR transactivation in human colonic epithelial T84 cells stimulated with carbachol, as well as in bombesin-stimulated Rat-1 fibroblasts stably transfected with the bombesin receptor. Furthermore, cell treatment with inhibitors with greater specificity towards PKCα, including Go6976, Ro 31-7549 or Ro 32-0432, also increased GPCR-induced EGFR transactivation in IEC-18, T84 and Rat-1 cells. Transfection of siRNAs targeting PKCα also enhanced bombesin-induced EGFR tyrosine phosphorylation in Rat-1 cells. Thus, multiple lines of evidence support the hypothesis that conventional PKC isoforms, especially PKCα, mediate feedback inhibition of GPCR-induced EGFR transactivation.
Kinetic relations and the propagation of phase boundaries in solids

This paper treats the dynamics of phase transformations in elastic bars. The specific issue studied is the compatibility of the field equations and jump conditions of the one-dimensional theory of such bars with two additional constitutive requirements: a kinetic relation controlling the rate at which the phase transition takes place and a nucleation criterion for the initiation of the phase transition. A special elastic material with a piecewise-linear, non-monotonic stress-strain relation is considered, and the Riemann problem for this material is analyzed. For a large class of initial data, it is found that the kinetic relation and the nucleation criterion together single out a unique solution to this problem from among the infinitely many solutions that satisfy the entropy jump condition at all strain discontinuities.
The cloud structure of the jovian atmosphere as seen by the Cassini/CIRS experiment

Abstract We analyze the thermal infrared spectra of Jupiter obtained by the Cassini-CIRS instrument during the 2000 flyby to infer temperature and cloud density in the jovian stratosphere and upper troposphere. We use an inversion technique to derive zonal mean vertical profiles of cloud absorption coefficient and optical thickness from a narrow spectral window centered at 1392 cm −1 (7.18 μm). At this wavenumber atmospheric absorption due to ammonia gas is very weak and uncertainties in the ammonia abundance do not impact the cloud retrieval results. For cloud-free conditions the atmospheric transmission is limited by the absorption of molecular hydrogen and methane. The gaseous optical depth of the atmosphere is of order unity at about 1200 mbar. This allows us to probe the structure of the atmosphere through a layer where ammonia cloud formation is expected. The results are presented as height vs latitude cross-sections of the zonal mean cloud optical depth and cloud absorption coefficient. The cloud optical depth and the cloud base pressure exhibit a significant variability with latitude. In regions with thin cloud cover (cloud optical depth less than 2), the cloud absorption coefficient peaks at 1.1 ± 0.05 bar , whereas in regions with thick clouds the peak cloud absorption coefficient occurs in the vicinity of 900 ± 50 mbar. If the cloud optical depth is too large the location of the cloud peak cannot be identified. Based on theoretical expectations for the ammonia condensation pressure we conclude that the detected clouds are probably a system of two different cloud layers: a top ammonia ice layer at about 900 mbar covering only limited latitudes and a second, deeper layer at 1100 mbar, possibly made of ammonium hydrosulfide.
A Simple Hemagglutination System Requiring Small Amounts of Red Cells and Antibodies

A method is described which permits dilute red cell suspensions (1/32%) to be used in plastic microtiter plates for detecting hemagglutinins at unusually high dilutions. The use of suitable additives to the hemagglutination mixture enables excellent settling patterns and a high sensitivity to be obtained. Direct agglutination, inhibition, enzyme promoted agglutination, and Coombs tests can all be performed. Quantitative studies demonstrate the discriminatory powers of the technic. The method may be useful for economizing in the consumption of reagents in blood grouping.
Autonomous Airborne Refueling of Unmanned Air Vehicles Using the Global Positioning System

Autonomous airborne refueling requires that the position of the receiving aircraft relative to the tanker be known very accurately and in real time. To meet this need, highly precise carrier-phase differential global positioning system solutions are being considered as the basis for navigation. However, the tanker introduces severe sky blockage into the autonomous airborne refueling mission, which reduces the number of visible global positioning system satellites and hence degrades the positioning accuracy. In this paper, we analyze the autonomous airborne refueling navigation problem in detail, define an optimal navigation architecture, and quantify navigation system availability. As part of this work, a high-fidelity dynamic sky-blockage model is developed and used to plan autonomous airborne refueling flight tests. The flight tests were conducted to obtain time-tagged global positioning system and attitude data that were processed offline to validate the blockage model.
American Community Organizations: A Historical Dictionary

An encyclopedic dictionary that treats organizations, persons, and federal legislation that document the history of grass-roots community organizing. Focusing on neighborhood associations in the US from the 1880s to the present, the work includes more than 100 signed entries, which average one to two pages each. Numerous cross-references and thorough name and subject indexes are included...[The] excellent bibliographic essay by Robert Fisher [contains] 12 pages of accessible books, articles, and papers on the topic as a whole and by time period. The editor has also provided a useful introductory essay on the changing notion of neighborhood. This well-planned and well-edited resource is further enhanced by its attractive typography and layout. Highly recommended to academic libraries with programs in sociology, social work, local politics, and urban history, and to all urban public libraries. Choice This new historical dictionary brings together informaton about the formative years of community organization and material on the more recent explosion in the organization of America's urban areas. The organizational activities included in this volume focus on the geographical community rather than on issue-oriented activities; are dedicated to the involvement of neighborhood residents in both the planning and implementation of local activities; and share a commitment to provide not only fuller services but also to serve as agents for potential social change.
Homocitrate synthase from yeast

Abstract Homocitrate synthase activity has been partially purified from yeast. Homocitrate synthase activity was sensitive to inhibition by lysine both in vivo and in vitro only at high concentrations of lysine. Two enzyme activities have been demonstrated in several strains of yeast by isoelectric focusing. The two enzymes were equally sensitive to inhibition by lysine. One enzyme activity was repressed to a greater extent when the culture medium was supplemented with excess lysine.
Hair pulling and its affective correlates in an African-American university sample

Like other clinical phenomena, repetitive hair pulling in African-Americans has attracted little systematic investigation. Slightly over 200 participants were recruited from a historically black university. Participants completed the Hair Pulling Scale [Stanley, M. A., Borden, J. W., Bell, G. E., & Wagner, A. L. (1994). Nonclinical hair pulling: phenomenology and related psychopathology. Journal of Anxiety Disorders, 8, 119-130], the Beck Depression Inventory, and the Beck Anxiety Inventory (BAI). Ten percent of the African-American sample thought about pulling out hair and 6.3% actually pulled out hair. A variety of types of affect was reported before, during, and after pulling or picking. Several statistically significant relationships were found: status as a person who thinks about pulling out hair is significantly correlated with anxiety as measured by the BAI (r=.265, p=.000), status as a person who pulls hair is significantly correlated with anxiety as measured by the BAI (p=.192, r=.007). Implications are discussed.
Ultrathin coating of plasma polymer of methane applied on the surface of silicone contact lenses.

Silicone rubber has great advantages as a contact lens material because of its very high oxygen permeability, softness, and excellent mechanical strength and durability. Practical application is hampered by inherent characteristics of elastomers, i.e., high tackiness and highly hydrophobic surface properties. By applying a thin layer, e.g., 5 nm, of plasma polymer of methane, it was found that all these disadvantages can be eliminated without sacrificing high oxygen permeation rate, e.g., less than 15% reduction. Optimization of operational parameters to achieve this task has been investigated. It was also found that under optimum conditions the coating withstood severe and repeated flexing of the contact lens.
Proteoglycans in the mouse interphotoreceptor matrix. I. Histochemical studies using cuprolinic blue

Cuprolinic Blue, when applied at a critical electrolyte concentration, can be utilized for assessing the localization and structural characteristics of proteoglycans with electron microscopy. We have used this cytochemical procedure to evaluate the distribution of proteoglycan in the interphotoreceptor matrix of the mouse retina. Cuprolinic Blue-positive filaments of two distinct morphological types were present surrounding both rod and cone photoreceptors. Large filaments, 115-135 nm long and 15-25 nm in diameter, were distributed in the interphotoreceptor matrix around the outer segment and outer portion of the inner segment. These filaments appeared linked to each other to form a complex meshwork. Smaller filaments, 60-70 nm long and 5-10 nm in diameter, were principally observed around the photoreceptor inner segments. Incubation of retinas with chondroitinase AC and chondroitinase ABC eliminated Cuprolinic Blue staining of both large and small filaments, whereas hyaluronidase treatment reduced the size of the filaments but did not eliminate their staining. When retinas were washed extensively prior to fixation and staining, Cuprolinic Blue-positive filaments remained associated with the photoreceptor cell surface. These results suggest that the interphotoreceptor matrix of the mouse retina contains at least two structural types of proteoglycan, of the chondroitin sulfate-type, which are differentially distributed in this compartment. One of the proteoglycans forms a complex meshwork which surrounds the photoreceptors. Both are insoluble and appear to be firmly attached to the photoreceptor plasma membrane.
Self-induced transparency modelocking of quantum cascade lasers in the presence of saturable nonlinearity and group velocity dispersion

We consider the impact of saturable nonlinearity and group velocity dispersion on self-induced transparency (SIT) modelocking of quantum cascade lasers (QCLs). We find that self-induced transparency modelocking in QCLs can be obtained in the presence of saturable nonlinearity if the saturable loss or gain is below a critical limit. The limit for the saturable loss is significantly more stringent than the limit for the saturable gain. Stable modelocked pulses are also obtained in the presence of both normal and anomalous group velocity dispersion when its magnitude is below a critical value. The stability limit for the saturable loss becomes less stringent when group velocity dispersion is simultaneously present. However, the stability limit for the saturable gain is not significantly affected. All these limits depend on the ratio of the SIT-induced gain and absorption to the linear loss. Realistic values for both the saturable nonlinearity and chromatic dispersion are within the range in which SIT modelocking is predicted to be stable.
Effect of pulsed progressive fluoroscopy on reduction of radiation dose in the cardiac catheterization laboratory.

Abstract The increased application of therapeutic interventional cardiology procedures is associated with increased radiation exposure to physicians, patients and technical personnel. New advances in imaging techniques have the potential for reducing radiation exposure. A progressive scanning video system with a standard vascular phantom has been shown to decrease entrance radiation exposure. The effect of this system on reducing actual radiation exposure to physicians and technicians was assessed from 1984 through 1987. During this time, progressive fluoroscopy was added sequentially to all four adult catheterization laboratories; no changes in shielding procedures were made. During this time, the case load per physician increased by 63% and the number of percutaneous transluminal coronary angioplasty procedures (a high radiation procedure) increased by 244%. Despite these increases in both case load and higher radiation procedures, the average radiation exposure per physician declined by 37%. During the same time, the radiation exposure for technicians decreased by 35%. Pulsed progressive fluoroscopy is effective for reducing radiation exposure to catheterization laboratory physicians and technical staff.
Intracranial choriocarcinoma causing precocious puberty and cured with combined modality therapy.

Precocious puberty can be caused by hormonally active tumours, which may arise intracranially. Treatment of these intracranial lesions traditionally involves biopsy and radiotherapy. Chemotherapy has been used recently, although radiotherapy has been given irrespective of the response to chemotherapy. We report a case of precocious puberty in an 8 year old boy due to a malignant intracranial germ cell tumour. Although one could speculate that he was cured by such combined modality therapy, the patient was left with several long-term problems. Radiotherapy was a major cause of these complications. Radiotherapy is now thought unnecessary for most extracranial germ cell tumours, as chemotherapy alone is curative in most patients
Accuracy in analog optical processors: statistical analysis

A statistical analysis of propagation, modulation and detection of signals in a generic optical processor is presented. The effects of diffraction, interchannel cross talk, and background radiation on system operation are considered. The mean, the mutual coherence function, and the probability density function of the optical output signal are derived in terms of those of the sources and the modulators in the processor. We then analyze the photodetection process, taking into acount the effects of nonideal detector characteristics and electronic postprocessing, and the mean and the autocorrelation function of the electrical output signal are obtained. The analytical form of the signal dependence of noise at the processor output is thus established. An integral equation, with a corresponding series solution, and a series expression are also derived for the probability density function of the photodetector output voltage. Use of these expressions is then demonstrated under certain simplifying conditions. These results form the foundation for future research on accuracy enhancement in analog optical processors.
Effects of dexamethasone, epidermal growth factor, and retinoic acid on rat submandibular acinar-intercalated duct complexes in primary culture.

Mature acini with attached segments of intercalated ducts were dissociated from the submandibular glands of rats and grown in primary culture on gels of reconstituted rat tail collagen. Screening evaluations indicated that the following new conditions promoted a substantial improvement in the survival of the cells as compared with our previously reported results: a) adding dexamethasone, epidermal growth factor, and retinoic acid to the medium, b) decreasing the fetal bovine serum in the medium to 1%; and c) adjusting the oxygen in the gas phase to 50%. A detailed evaluation, including light and electron microscopy and biochemical analysis, then provided the following observations. The acinar-ductal complexes enlarged throughout the 22-d culture period, and after 4d sheets comprised of a one- to two-cell thick layer of acinar cells spread among the complexes. Synthesis of mucin, and its secretion in response to norepinephrine or cAMP, dropped precipitously to very low levels after 2 d. However, synthesis of DNA, general proteins, and glycoproteins dropped only transiently after 2 d, rising to levels approaching those of freshly dissociated complexes by 22 d. These data indicate that a shift occurred from the synthesis of large quantities of secretory proteins and glycoproteins, especially mucins, during the first 2d in culture, to other materials thereafter. Overall, the new culture conditions resulted in substantial growth and survival of acinar cells through 22 d in primary culture, but the important acinar characteristic of the synthesis and secretion of mucins was essentially lost after 4 d.
Support provider mood and familiar versus unfamiliar events: An investigation of social support quality

Much of what communication scholars know about the production of effective comforting messages comes from the constructivist framework of Applegate (1980), Burleson (1985), and others. This paper extends this framework by addressing two questions put forth by scholars in this area, namely, what is the influence of cognition‐inhibiting situational variables such as mood on the generation of sophisticated, person‐centered comforting messages, and is this influence greater in situations requiring increased cognitive processing (Burleson & Planalp, 2000). In this study, support providers’ moods were manipulated before they were presented with either a familiar or an unfamiliar hypothetical support scenario. As hypothesized, results showed that supportive messages provided in response to a familiar situation were significantly more sophisticated than messages provided in response to an unfamiliar situation. Participants exposed to the happy mood induction encoded significantly more sophisticated comforting mes...
A method for repeated evaluation of pulmonary performance in unanesthetized, unrestrained guinea pigs and its application to detect effects of sulfuric acid mist inhalation☆

A method is presented to evaluate pulmonary performance in unrestrained and unanesthetized guinea pigs by measuring the increase in tidal volume (VT), respiratory frequency (f), and minute ventilation (VT · f) induced by exposure to a mixture containing 10% CO2, 20% O2, and 70% N2. The increase was measured before and after exposure to various concentrations of sulfuric acid mist. Exposures to sulfuric acid produced a concentration-dependent reduction in CO2-induced increases in VT, f, and VT · f. Recovery from pulmonary injury induced by exposures to sulfuric acid was apparent from daily CO2 challenge. The method is simple, noninvasive, and required neither physical restraints nor anesthesia. The results of the CO2 challenge were reproducible for each animal over a 5-day period.
Re‐imagining nationalism: New studies in Arab, Turkish, and Israeli historiography

James Jankowski and Israel Gershoni eds., Rethinking Nationalism in the Arab Middle East, (New York: Columbia University Press, 1997). xxvi + 287 pages. Notes to p. 336. Glossary to p. 340. Bibliography to p. 354. Index to p. 372. Paperback $19.50. Sibel Bozdogan and Resat Kasaba eds., Rethinking Modernity and National Identity in Turkey, (Seattle: University of Washington Press, 1997). xi + 260 pages. Index to p. 270. Paperback $22.50. Laurence J. Silberstein, The Postzionism Debates: Knowledge and Power in Israeli Culture, (London: Routledge Press, 1999). x + 209 pages. Notes to p. 239. Bibliography to p. 261. Index to p. 275. Paperback $19.99.
Pediatric and adolescent women's health curriculum

Background Pediatric training has often focused on treating infants and children. Pediatricians need to be knowledgeable about the different psychological and sexual changes their patients are experiencing as they become adults. The purpose of developing the Pediatric and Adolescent Women's Health Curriculum was to provide Pediatric residents with the training they need to care for their female adolescent patients. Methods An evaluation of the existing Pediatric residency curriculum was done, as well as an extensive literature search for relevant issues affecting women's health. Then, additional didactic and clinical experiences focusing on both reproductive and non-reproductive women's health issues were made available within the curriculum. Results Building on required rotations in adolescent, developmental and behavioral medicine, residents are given the opportunity to further their gynecological and reproductive health care training through a formal elective in advanced gynecology. This includes developing procedural competency in the diagnosis of cervical dysplasia using colposcopy, cervical biopsy and treattnent modalities, and pregnancy termination. This is a time to expand knowledge and management skills in areas such as dysfunctional uterine bleeding, anovulation, hirsutism, precocious puberty, and dysmenorrhea. The second elective course in the curriculum provides exposure to Perinatology. Teenage pregnancy is a problem for the mother as well as the fetus. Pediatricians need to know how to treat their pregnant patients that have cystic fibrosis, hypertension, asthma, juvenile rheumatoid arthritis, and a multitude of other medical illnesses. It is also important to recognize the complications that may occur at delivery and affect the infant. In addition to these two rotations, every required and elective rotation is supplemented with issues concerning women's health, including an emphasis on health promotion and disease prevention. Residents are also required to attend monthly grand rounds which cover such topics as obesity, evaluating a breast mass, depression, physiology and development, and preconception counseling. Conclusion Women's health care can be successfully incorporated into an existing Pediatric resident curriculum with minor modifications. It is imperative that physicians be adequately trained to care for children of all ages, from birth to adulthood. Currently, Pediatrics is often deficient in curriculum relating to women's health care, especially non-reproductive issues. This information can be made available and proficiency obtained for those interested through our existing Pediatric and Adolescent Women's Health Curriculum.
Biomechanics of the Patellofemoral Joint

The biomechanics and kinematics of the patellofemoral joint are the result of a complex assortment of static and dynamic conditions. This article will present a review of our basic understanding of these conditions and place them in the context of necessary information required when considering surgical interventions. The importance of this information becomes highlighted when one considers that the knee is a coupled mechanical system, and changes in any single component of the system can affect any of the remaining parts of the system.
Measuring and improving the quality of dying and death.

Improving end-of-life experience is a major challenge to successful aging. Deaths that are reasonably free of discomfort, in accordance with patients' wishes, and within acceptable professional and ethical standards are high-quality deaths. The authors developed a 31-item measure of the quality of dying and death and applied it in a community sample and a sample of hospice enrollees. Scores on the Quality of Dying and Death Instrument and measures of perceived quality of care were collected from patients' loved ones after death. Higher overall after-death ratings of the quality of care received from all providers and from physicians were associated with higher-quality dying and death. How well patients' symptoms were controlled in the community study and how well wishes were followed and treatments were explained in the hospice study were associated with higher-quality dying. Major challenges to end-of-life research include recruiting representative population samples, given widespread reluctance of patients and loved ones to participate in research at the end of life; important variation in evaluations among different reporters after death; reluctance of loved ones to assign negative evaluations to dying experiences after death; and the highly individual and dynamic nature of dying experiences. Overcoming these challenges is of great importance in the search for the social, organizational, and individual determinants of high-quality dying in the U.S. cultural and health care context.
Discrimination of snakes by two populations of black-tailed prairie dogs

Black-tailed prairie dogs (Cynomys ludovicianus) are large, diurnal, colonial rodents whose basic socialunit is the coterie (Hoogland, 1981; King, 1955), normally containing one adult male, several adult females,yearling males and females, and young of the year (pups). Prairie dogs commonly are confronted with bothvenomous rattlesnakes (Crotalus sp.) and nonvenomous bullsnakes (Pituophis melanoleucus sayi); theyactively harass these snakes (Halpin, 1983; Loughry, 1987a; Owings and Loughry, 1985; Owings and Owings,1979). Other ground squirrels also harass snakes and behave differently toward different species and sizesof snakes (Coss and Owings, 1985). In this paper I ask whether prairie dogs make such distinctions amongsnakes. I also examine whether population history influences snake discrimination by comparing the behaviorof a snake-experienced and a snake-naive population.Prairie dogs were studied at Lower Rankin Ridge in Wind Cave National Park, South Dakota, wheresnakes are rare and Muleshoe National Wildlife Refuge, Muleshoe, Texas, where snakes are common (Lough-ry, 1988). All prairie dogs were dye-marked and ear-tagged. Pups were marked before mixing of litters, somaternity of pups was certain. Paternity of pups was inferred on the basis of observations of breedingbehavior or by tenure of a male within a coterie during the breeding season (Foltz and Hoogland, 1981;Loughry, 1987a, 1988).Large and small rattlesnakes and bullsnakes were tethered (Hennessy et aI., 1981) within a coterie nearan active burrow. In coteries that produced pups, this burrow contained pups. Although the same snakes
Radiation sensitivity of the hibernating ground squirrel, Citellus tridecemlineatus.

SummaryThe basic conclusion of this report is that irradiated hibernating ground squirrels do not respond as “active” animals following arousal as has been hitherto re-ported, rather, there is a protective effect relatable to hibernation. The hibernators have a longer “mean survival time” and an increased LD50 (30).
Repensando a privacidade: autonomia, identidade e a controvérsia sobre o aborto

A partir de um dialogo com a critica feminista as dicotomias entre o publico e o privado, a autora define os limites e contornos do direito a privacidade, considerado um aspecto central a autonomia e ao direito ao corpo. O comunitarismo e as correntes feministas que defendem a superacao das fronteiras entre publico e privado sao criticados pela incapacidade de garantir o respeito as decisoes autonomas dos individuos, sobretudo no que concerne seu corpo, sua vida afetiva e aspectos relevantes da sua identidade. A garantia da privacidade e vista como algo necessario a afirmacao das identidades individuais e a protecao dos individuos em relacao as praticas e valores majoritarios na comunidade em que estao inseridos. O direito ao aborto constitui o direito a privacidade, assim definido.
Axisymmetric buckling of rigidly clamped hemispherical shells

The shell is subjected to a uniform compressive surface load (either a pressure or a centrally directed load). The results of a numerical study are summarized and compared with experiments.