cssi/SciSciGPT-SciSciNet huggingface dataset:
Renal tubular dysfunction during long-term adefovir or tenofovir therapy in chronic hepatitis B.

Summary Background Adefovir and tenofovir are nucleotide analogues used as long-term therapy of chronic hepatitis B. Side effects are few, but prolonged and high-dose therapy has been associated with proximal renal tubular dysfunction (RTD). Aim To assess the incidence of RTD during long-term nucleotide therapy of chronic hepatitis B. Methods A total of 51 patients being treated at the Clinical Center, National Institutes of Health were studied. Diagnosis of RTD required de novo appearance of at least three of five features: hypophosphataemia, hypouricaemia, serum creatinine elevation, proteinuria or glucosuria. Results Among 51 patients treated for 1–10 (mean 7.4) years with adefovir (n = 42), tenofovir (n = 4) or adefovir followed by tenofovir (n = 5), 7 (14%) developed RTD. Time to onset ranged from 22 to 94 (mean 49) months with an estimated 10-year cumulative rate of 15%. All seven had low urinary percent maximal tubular reabsorption of phosphate (<82%). Patients with RTD were older (58 vs. 44 years; P = 0.01) and had lower baseline glomerular filtration rates (82 vs. 97 cc/min; P = 0.08) compared to those without; but did not differ in other features. Six patients with RTD were switched to entecavir, all subsequently had improvements in serum phosphate (2.0–3.0 mg/dL), creatinine (1.6–1.1 mg/dL), uric acid (2.7–3.8 mg/dL) and proteinuria. Conclusions Renal tubular dysfunction develops in 15% of patients treated with adefovir or tenofovir for 2–9 years and is partially reversible with change to other antivirals. Monitoring for serum phosphate, creatinine and urinalysis is prudent during long-term adefovir and tenofovir therapy.
Should we screen for occult coronary artery disease among asymptomatic patients with diabetes

Diabetes mellitus predisposes people to premature atherosclerotic coronary artery disease (CAD). The risk of a myocardial infarction in diabetics without overt evidence of obstructive CAD matches that of patients without diabetes who have had a previous myocardial infarction. The available data suggest that occult CAD is a common finding among asymptomatic diabetics, ranging from 20% to >50%. The diagnostic accuracy of myocardial perfusion single-photon emission computed tomography (SPECT) in diabetics appears to be comparable to that observed in nondiabetic individuals. As shown in other patient groups, the ischemic burden assessed by stress SPECT in subjects with diabetes is also linked to their increased risk of adverse cardiovascular events. Among patients with normal stress SPECT, however, those with diabetes are at significantly greater risk than non-diabetics. Testing diabetics with an abnormal resting electrocardiogram or with evidence of peripheral or carotid occlusive arterial disease appears to result in an excellent yield of abnormal SPECT findings, as does testing in the setting of dyspnea. However, recent evidence suggests that achieving an adequate yield in asymptomatic diabetics without overt evidence of CAD is a greater challenge. Further investigation of sequential testing strategies is needed in order to identify an efficient means for screening asymptomatic patients with diabetes.
Statistical representation of high-dimensional deformation fields with application to statistically constrained 3D warping

This paper proposes a 3D statistical model aiming at effectively capturing statistics of high-dimensional deformation fields and then uses this prior knowledge to constrain 3D image warping. The conventional statistical shape model methods, such as the active shape model (ASM), have been very successful in modeling shape variability. However, their accuracy and effectiveness typically drop dramatically in high-dimensionality problems involving relatively small training datasets, which is customary in 3D and 4D medical imaging applications. The proposed statistical model of deformation (SMD) uses wavelet-based decompositions coupled with PCA in each wavelet band, in order to more accurately estimate the pdf of high-dimensional deformation fields, when a relatively small number of training samples are available. SMD is further used as statistical prior to regularize the deformation field in an SMD-constrained deformable registration framework. As a result, more robust registration results are obtained relative to using generic smoothness constraints on deformation fields, such as Laplacian-based regularization. In experiments, we first illustrate the performance of SMD in representing the variability of deformation fields and then evaluate the performance of the SMD-constrained registration, via comparing a hierarchical volumetric image registration algorithm, HAMMER, with its SMD-constrained version, referred to as SMD+HAMMER. This SMD-constrained deformable registration framework can potentially incorporate various registration algorithms to improve robustness and stability via statistical shape constraints.
Characterization of the Ehrlich ascites tumor plasma lipoproteins.

Abstract 1. 1. The lipoproteins of the Ehrlich ascites tumor plasma were separated into 3 distinct fractions, very low density, low density and high density lipo-proteins by preparative ultracentrifugation combined with agarose column chromatography. 2. 2. High density lipoproteins contained 74% of the total protein in the lipoproteins. By contrast, most of the lipids were present in the very low density lipo protein fraction. 3. 3. The fatty acid compositions of the cholesteryl esters were appreciably different in the very low, low and high density lipoproteins, whereas phospho-lipid and triacylglycerol fatty acid compositions were quite similar in the 3 lipoprotein fractions. 4. 4. Very low and high density apoprotein electrophoretic patterns on sodium dodecyl sulfate-acrylamide gels were similar to those observed in the corresponding lipoprotein fractions obtained from other mammalian species. The low density fraction, however, contained 7 apoprotein bands, and 32% of the low density apoprotein was soluble in tetramethyl urea. 5. 5. The average molecular weights as determined by analytical ultracen-trifugation were 2 · 107 (very low density), 6 · 106 (low density) and 4.4 · 105 (high density).
Experimental study of crosstalk in pump-modulated parametric multicasting device

We present an experimental study of crosstalk in a 1:40 multicasting architecture based on a one-pump modulated parametric amplifier. The optimal operating region is determined by an extensive sweep of pump and signal powers.
Mycophenolate mofetil (RS-61443): Mechanisms of action and effects in transplantation

W hereas cyclosporine and glucocorticoids have had a major impact in transplantation, their side effects are well known. Cyclosporine efficiently suppresses T-cell-mediated immune responses and acute rejection of allografts. Nevertheless, many human organ graft recipients who have been given combination therapy with cyclosporine and steroids, with or without azathioprine, have episodes of rejection. Often these are controlled by high-dose bolus steroid and/or OKT3 therapy. However, such treatments may increase susceptibility to infections and the eventual development of lymphomas. The first requirement is for a drug that can be used in combination therapy with well-tolerated doses of cyclosporine to decrease the incidence of rejection episodes in allograft recipients. The second is for a drug that can reverse ongoing rejection without increasing susceptibility to infections or causing other limiting side effects. Now that grafts have better survival rates, other problems are emerging. The problem of chronic rejection and its effects on the ~asculature of grafted organs is becoming recognized as a major limitation of long-term graft survival. A third and major requirement in transplantation is for a drug that can prevent chronic rejection when used over long periods. With these considerations in mind, we and other investigators in the laboratories at Syntex and the University of Wisconsin developed a novel immunosuppressive drug, demonstrated efficacy in experimental animal models of transplantation, and conducted the first human trials in allograft recipients. Our strategy was to define a biochemical pathway that is especially important for proliferation of human T and B lymphocytes and, by inhibiting that pathway, to suppress the proliferation of clones of lymphocytes responding to antigenic stimulation.
Magnetic gradiometer based on a high-transition temperature superconducting quantum interference device for improved sensitivity of a biosensor

We describe a gradiometer based on a high-transition temperature Superconducting Quantum Interference Device (SQUID) for improving the sensitivity of a SQUID-based biosensor. The first-derivative gradiometer, fabricated from a single layer of YBa{sub 2}Cu{sub 3}O{sub 7-x}, has a baseline of 480 {micro}m and a balance against uniform fields of 1 part in 150. Used in our SQUID ''microscope,'' it reduces parasitic magnetic fields generated by the measurement process to the level of the SQUID noise. The gradiometer-based microscope is two orders of magnitude more sensitive to super paramagnetic nanoparticles bound to biological targets than our earlier magnetometer-based microscope.
On the Eve of War: Authoritarianism, Social Dominance, and American Students’ Attitudes Toward Attacking Iraq

In the week before the 2003 American attack on Iraq, the effects of authoritarianism and the social dominance orientation on support for the attack were examined. Based on prior research on the nature of these constructs, a structural model was developed and tested. As predicted, authoritarianism strengthened support for the attack by intensifying the perception that Iraq threatened America. Social dominance increased support by reducing concern for the likely human costs of the war. Both also increased blind patriotism, which in turn reduced concern for the war’s human costs and was reciprocally related to the belief that Iraq threatened America.
Nonminimum phase non-Gaussian deconvolution

A procedure for deconvolution of nonminimum phase non-Guassian time series based on the estimation of higher order (greater than two) spectra is given. This can be applied to the analysis of seismograms. The procedure allows estimation of the wavelet. Knowledge of cumulant spectra of order greater than two allows estimation of the phase of the wavelet. In this way one has access to information not available in the ordinary second-order deconvolution procedures. Computational details of the method for estimating the phase of the wavelet are given. There are simulated illustrative examples. One of the examples is based on an actual reflectivity series from a sonic well log. The method is effective asymptotically in the nonminimum phase non-Gaussian context where the Wiener-Levinson procedure does not apply.
Dialectics in the Longer Durée: The IIPEC Model of Inter-imperial Economy and Culture

AbstractThis essay combines new evidence from world history with postcolonial and materialist theory to develop an interdisciplinary model of dialectics in world politics. The argument is both theoretical and historical. Focused on the global field of empires jockeying in every period, whose material productions accrue over successive periods, the essay models an inter-imperial theory of political economy and culture (IIPEC), with attention to anti-imperial as well as imperial actors. The theory introduces three dialectical concepts (co-formation, co-production, and accretion), which explain the linked emergence of states, capitalist economies, material infrastructures, and cultural institutions. Applied to new historical data on states outside of Europe, including in ‘medieval’ periods, the IIPEC analysis reveals that these processes of linked emergence predate–and prepare–the rise of European nation-states. The IIPEC model thus reframes the Westphalian account of state formation within a transhemispheri...
Connected CdSe nanocrystallite networks

The optical properties of semiconductor nanocrystallites, or small quantum dots, are well understood, but little is known about nanocrystallite networks. Here we report preliminary results on a glassy network of CdSe nanocrystallites connected by molecular bridges. This network has been analyzed by transmission electron microscopy (TEM) and small angle X-ray scattering to determine its structure, and to see if long range order is present. The effect of nanocrystallite interactions on electron-hole recombination is inferred from characterization by UV-VIS absorption and photoluminescence.
Factors affecting the reproductive success of the crab spider Misumenoides formosipes : the covariance between juvenile and adult traits

To examine the importance of covariance between stages in traits related to foraging, we quantified the relationships between reproductive success and sizerelated variability in weight gain in juvenile and adult instars of the crab spider Misumenoides formosipes (Araneae: Thomisidae). Prereproductive weight and fecundity are both highly correlated with carapace width, a linear measure of size which does not change within an instar. In field populations, adult females with larger carapaces gain more weight and are more likely to reproduce than females with smaller carapaces. The growth rate of spiders fed ad libitum in the laboratory is unrelated to size, suggesting that size-related differences in the field are due to variation in prey-capture success. Adult females with a carapace width less than 3.4 mm comprised 22% of the population, but were never found to reproduce. Of the individuals that did reproduce, a 17% increase in carapace width resulted in a 100% increase in fecundity. Juvenile stages must be examined to understand adult foraging and reproductive success, because the net weight gained by juvenile instars determines adult size. The final weight gained by spiders in the antepenultimate and penultimate instars explained nearly all the variation in carapace width in the penultimate and adult instars, respectively. We found that constraints on foraging in late juvenile stages are different from the adult stage. Penultimate foraging behavior differs from that of adults, because of constraints on foraging in the period preceding ecdysis. Additionally, in both late juvenile instars, carapace width had little or no effect on the final weight gained within the instar suggesting that factors that affect foraging are different between the juvenile and adult stages. These analyses stress the fact that to fully understand the effects of foraging on reproductive success, we must examine stage-specific constraints throughout an organism's life history.
Rotational and Divergent Geopotential Components

Abstract It has been traditional in meteorology to divide the velocity field up into rotational and divergent components, but not the geopotential field. Yet any balance condition, such as the geostrophic relation or linear balance equation, is a diagnostic relation which states that not only can the balanced velocity field be computed from the geopotential field, but also that the geopotential can be derived from the velocity field. If the latter approach is adopted, then the difference between the observed and computed geopotential is the quantity we refer to as the divergent, or in some cases, ageostrophic, geopotential. In fact, for any balance set of equations, it is essential to partition the geopotential in such a way in order to derive an equivalent set of momentum equations. The momentum equations equivalent to the linear balance set of equations are given. The linear balance equation is integrated to give a diagnostic relation between the rotational wind components and the gradient of the rotati...
Physical functioning and rehabilitation for the cancer survivor.

There are more than 13.8 million survivors of cancer living in the United States. Up to 20% of survivors of childhood-onset and 53% of survivors of adult-onset cancer have problems with physical function as a result of their cancer and or its treatment. These problems may be immediately apparent, during, or soon after initial cancer treatment, or may appear days, months, or years later as the cancer survivor ages. Unfortunately, rehabilitation services and providers are not easily or systematically accessible in today’s healthcare system. Rehabilitation services that restore or ameliorate early functional loss or that protect against or minimize the impact of later-onset organ system dysfunction are available, at least in larger comprehensive cancer center settings. This report describes physical function, details the evolution of cancer rehabilitation, and identifies cancer survivors who may benefit from rehabilitation services. Additionally, the evidence for specific approaches to rehabilitation, intervention, and prevention of functional loss are reviewed. Finally, we summarize the mechanisms used to measure physical function and stress the need for additional research to support rehabilitation services for cancer survivors.
International Productivity Comparisons Built from the Firm Level

ost international comparisons of economic productivity work throughaggregate calculations of labor productivity or total factor productivityat the level of the national income, or sometimes at the broad sector orindustry level (for example, Jorgenson, 1995; Wagner and Van Ark, 1996). A lot hasbeen learned in this way. Increasingly, however, there have been attempts tosupplement aggregate calculations with micro-level information about individualdepartments, ﬁrms or narrowly deﬁned industries and their operations. A variety ofsuch studies has been done.One line of research has used data from single establishments, especially inU.S. manufacturing, to study productivity and employment patterns (Griliches,1998; Olley and Pakes, 1996; Baily, Hulten and Campbell, 1992). Another approachhas focused on the ﬁrms or plants within a particular industry (for example,Womack, Jones and Roos, 1990, on the auto industry). Still another line of researchstudies the frequency distribution of plant-level changes in output and employ-ment, revealing large gross ﬂows even when net changes at the industry level aresmall (Davis, Haltiwanger and Schuh, 1996). The National Bureau of EconomicResearch has developed a program of “pin factory” visits as a way of bringingﬁrst-hand information into the analysis of economic performance ( Jaffe, Trajten-berg and Fogarty, 2000; Freeman and Kleiner, 2000; Borenstein and Farrell, 2000;Helper, 2000).We have been extensively involved, along with a group of other academicadvisers, in a series of international comparative performance studies carried out by
Deposit rate ceilings and monetary transmission in the US

Abstract Establishing the existence and nature of changes in the conduct and transmission of monetary policy is key in understanding the remarkable macroeconomic performance of the US since the mid-1980s. This paper presents evidence on a phenomenon of disintermediation occurring during the major recessions in the 1960s and 1970s, but absent ever since, and shows that disintermediation is closely linked to the existence of deposit rate ceilings under regulation Q. In a monetary DSGE model that incorporates deposit rate ceilings as occasionally binding constraints, the regulation alters the behavior of money aggregates and exacerbates the drop in economic activity following a monetary tightening. The results of a threshold VAR lend support to the main theoretical predictions of the model.
The proper use of citation data in journal management

Journal impact factors (IF) are often maligned in editorials found in scientific publications, yet citation data can be used appropriately in journal management. The editors of Laboratory Investigation have found that weekly tracking of citation data for this and other highly ranked pathology journals provides valuable feedback on editorial performance and enables us to predict accurate IFs at least six months in advance. Once the IFs are released, it is useful to quantify the contributions of specific article categories, such as reviews and research articles, to the official IFs. In an ongoing attempt to understand the relationship between article downloads and eventual citations, we also analyze the citation rate of papers that had previously been the most frequently accessed on our web site. Finally, as a measure of editorial judgment, the papers that contributed no citations to the journal’s IF are examined as are the papers that were rejected by Laboratory Investigation (Lab. Invest.) but subsequently published elsewhere. Thus the editors of Lab. Invest. use citation data in several ways to measure our progress in elevating the quality of the journal and understand the citation dynamics of papers we publish, while remaining true to the journal’s fundamental operating premise: Publish high-quality original work relating to the mechanisms of disease.
Antibody to the extracellular domain of the low affinity NGF receptor stimulates p75NGFR-mediated apoptosis in cultured sympathetic neurons

Recent evidence has established a role for p75NGFR in developmentally regulated neuronal cell death. Although cell death due to NGF withdrawal is a well described, apoptosis in sympathetic neurons through stimulation of p75NGFR has not been clearly demonstrated. We have found that an antibody directed against the extracellular domain of murine p75NGFR profoundly effects the survival of short-term cultures of sympathetic neurons. Rat superior cervical ganglion neurons grown in the presence of NGF and treated with the bioactive antibody (9651) display a dose-dependent increase in cell death. This effect was independent of NGF concentration and partially reversed by either depolarizing stimuli or forskolin. The response to 9651 seems to act directly through a p75NGFR-mediated pathway and not by disturbing p75NGFR/TrkA interactions. Moreover, the kinetics of antibody stimulated cell death was more rapid than the cell death resulting from removal of NGF and treatment with CNTF failed to promote neuronal survival in the presence of 9651. Initiation of cell death is often associated with decreased NFκB activity, whereas survival or rescue correlates with increased NFκB. Increases in NFκB, however, have been observed in neurons in several diseases and late in apoptosis in differentiated PC12 cells. Time course studies revealed a rapid decrease in NFκB activity and a slight, but persistent increase in binding that correlated with decline in cell numbers 3 hr after treatment. These results suggest the cell death program is initiated shortly after antibody activation of p75NGFR and a subpopulation of cells may remain susceptible to rescue. J. Neurosci. Res. 64:331–340, 2001. © 2001 Wiley-Liss, Inc.
Normative ranges and specificity of the multifocal VEP.

Purpose: To describe a normative database for the multifocal VEP (mfVEP) and to evaluate specificity for a range of cluster criteria. Methods: One hundred persons (62 females and 38 males) with normal visual fields and ranging in age from 21.6 to 92.4 years participated in this study. Self-reported race in 80 of these 100 persons was `White or Caucasian,' eight were `Black or African-American,' eight were `Asian,' and four were `Hispanic or Latino.' Pattern-reversal mfVEPs were obtained using a dartboard stimulus pattern in VERISTM and two 8-min runs per eye were averaged. A bootstrap technique was used to estimate the normal range of mfVEP response signal-to-noise ratio (SNR) and inter-ocular amplitude ratio at each location. Specificity (1 – false alarm rate) was evaluated for a range of cluster criteria, whereby the number and probability level of the points defining a cluster were varied. Results: There was no overall effect of age on SNR (r2=0.16, p=0.22) nor was the interaction between age and location significant (F=0.83, p=0.82, ANOVA). The location with the largest age effect had an r2 of only 0.13. There was a small but significant effect of sex (t=2.1, p=0.04) such that SNR was slightly (11) larger in females than males, but there was no significant interaction between sex and age (t=0.82, p=0.41). There was a slight trend toward higher SNR in the Asian group and lower SNR in the African-American group, but the overall effect of race was not significant (F=1.99, p=0.12). Specificity depended on the number and probability level of the points defining a cluster. Specificity did not vary by age group in a simple monotonic manner. False positive rates were slightly higher in females than males, and slightly higher in the African-American group as compared with the Asian group. Conclusions: Excellent specificity can be achieved for the mfVEP by using particular cluster criteria for monocular and inter-ocular tests. The effects of age, sex, and race were all very small and only the effect of sex was statistically significant. This normative database can be used for analyses of mfVEP results from individual patients with little risk that demographic factors such as age and sex will confound diagnostic accuracy.
Integrating Multicultural Activities Across the Mathematics Curriculum

Integrating multicultural activities into mathematics instruction at all grade levels helps to foster appropriate and desirable attitudes about mathematics and its role in our culture. In particular, multicultural activities can be instrumental in removing the stigma of mathematics as being an elitist discipline pursued by a select few.
Colleague vs. tool: Effects of disclosure in human-robot collaboration

We report the results of an experiment examining how an autonomous mobile robotpsilas disclosure of task versus affective information influences peoplepsilas feelings about a robot when working on a collaborative task. In a 3 times 2 experiment, we examined disclosure (task, affective and no disclosure) and the trigger that produced the disclosure (automatic vs. on-demand). We hypothesized that a robot disclosing task information would increase peoplepsilas sense of control because it provides awareness about the task situation, but that affective information would decrease peoplepsilas sense of control. We also predicted that people would like robots better when they disclose affective information. Our findings confirm that people both felt less in control and liked the robot more when the robot disclosed its affective state. We further found that providing people with the ability to control disclosure (on demand vs. automatic disclosure), increased their sense of control, but decreased their liking of the robot. This research suggests the need to weigh a potential tradeoff between designing robot collaborators that evoke perceptions of control versus liking. In the discussion, we explore design implications and how different combinations of disclosure types and triggers may optimize both feelings of control and liking in human-robot collaboration.
Hemophilus influenzae pyarthrosis and meningitis treated with aureomycin

Summary A case of H. influenzae causing pyarthrosisand meningitis treated with aureomycin is described.
Tachykinins and their possible modulatory role on testicular function: a review

Tachykinins are vasoactive and smooth muscle-contracting peptides with widespread localizations. Tachykinins have been localized in the nerve fibres that supply the testes, in the Leydig cells of different animal species, and also in Sertoli cells of the Siberian hamster testes. The presence of substance P (SP) has also been demonstrated in ejaculated human spermatozoa and in the seminal plasma. Tachykinins have been shown to inhibit the release of testosterone by testicular fragments or by isolated Leydig cells in vitro. Acting on Sertoli cells, tachykinins have been shown to stimulate the release of lactate and transferrin by these cells in vitro, and also to stimulate aromatase activity. Leydig and Sertoli cells express the Preprotachykinin A gene, and this fact strongly suggests that tachykinins can be synthesized in the testes. These findings suggest that tachykinins may have a physiological function in the testes as modulators of the functions of the different cell types contained in these organs.
Identification of Novel Epigenetic Markers for Clear Cell Renal Cell Carcinoma

Purpose: We identified significantly hypermethylated genes in clear cell renal cell carcinoma.Materials and Methods: We previously identified a set of under expressed genes in renal cell carcinoma tissue through transcriptional profiling and a robust computational screen. We selected 19 of these genes for hypermethylation analysis using a rigorous search for the best candidate regions, considering CpG islands and transcription factor binding sites. The genes were analyzed for hypermethylation in the DNA of 38 matched clear cell renal cell carcinoma and normal samples using matrix assisted laser desorption ionization time-of-flight mass spectrometry. The significance of hypermethylation was assessed using 3 statistical tests. We validated the down-regulation of significantly hypermethylated genes at the RNA and protein levels in a separate set of patients using reverse transcriptase-polymerase chain reaction, immunohistochemistry and Western blots.Results: We found 7 significantly hypermethylated regions f...
Quantitative X-ray spectroscopy of sodium Z-pinch plasmas for Na/Ne photopumping

Abstract Spectra of sodium K-shell x-ray emission were measured for implosions of sodium-bearing plasmas produced on the Naval Research Laboratory Gamble II pulsed-power generator. Sodium fluoride from a capillary discharge provided the initial plasma for these fast Z-pinch implosions. Spatially-resolved images, corresponding to sodium K-shell x-rays from a 3 to 4 cm long plasma column, were recorded with a curved-crystal spectograph. Non-uniform emission was observed along this column. The diameter of the plasma along the column (1–5 mm) was determined from time-integrated pinhole-camera images, and the duration of the x-ray emission (15–23 ns FWHM) was measured with a vacuum x-ray diode. Absolute emissivities were determined for x-rays from the n=2-1 and n=3-1 transitions in Na X and Na XI. Emissivities calculated using a collisional-radiative equilibrium model were fitted to these measurements to determine plasma temperatures of 230 to 550 eV and electron densities of 0.2 to 4.0 × 1020 cm-3 at several locations along the plasma column. The slope of the recombination continuum was also used to determine temperatures of 200 to 300 eV and 200 to 400 eV for Na X and Na XI ions, respectively. Absolute intensity measurements of the n=2-1 line emissions from Na X and Na XI, averaged over the entire plasma length, indicated shot-to-shot variations of more than a factor of two in these implosions.
The Influence of Social Problem-Solving Ability on the Relationship Between Daily Stress and Adjustment

This study examined the role of social problem solving as a moderator and a mediator of the relationship between daily stressful events and adjustment in a sample of 259 college students. Problem solving was assessed by the Social Problem-Solving Inventory-Revised, which provides scores for global problem-solving ability as well as five specific problem-solving dimensions, namely, positive problem orientation, negative problem orientation, rational problem solving (i.e., effective problem-solving skills), impulsivity/carelessness style, and avoidance style. Adjustment was assessed by using the scores for internalizing symptoms and externalizing symptoms from the Adult Self-Report. Because of significant gender differences on the major study variables, results were analyzed separately for men and women. The most consistent finding was for the importance of negative problem orientation as a moderator or a mediator of the relationship between daily stress and adjustment. In women, negative problem orientation, impulsivity/carelessness style, and avoidance style were all found to mediate internalizing and externalizing symptoms. In addition, positive problem orientation mediated internalizing symptoms. In men, negative problem orientation was found to be a moderator for externalizing symptoms and a mediator for internalizing symptoms. The gender differences and implications for clinical practice were discussed.
Fossil Communities in Paleoecology: Their Recognition and Significance

Fossil assemblages consist of individuals that were members of one or more ancient communities. Four types of fossil assemblages (fossil communities, residual or winnowed fossil communities, transported fossil assemblages, and mixed fossil assemblages) may be differentiated on the basis of amount, and in some cases, cause of preburial alteration. The most damaging agents to marine communities are predators, scavengers, and especially bottom currents which selectively remove shells. To assess the preburial alteration of a particular fossil assemblage one must evaluate as many of the following criteria as can be reasonably applied: size-frequency distributions, ratio of articulated to disarticulated valves, ratio of opposite valves, dispersion of fossils, population density, community density, faunal composition and diversity, orientation of clastic particles (including fossils), texture, sorting, and structure of sedimentary aggregate, lithofacies relationships, surface condition of fossils, and ratio of whole to fragmented shells. Replacement, leaching, and crushing of shells are the causes of most postburial alteration and may profoundly influence the criteria for preburial alteration. Analysis of a fossil assemblage from the Pennsylvanian of Nebraska indicates that the specimens have been subject to considerable postburial crushing which has reduced the significance of some of the criteria for assessing preburial alteration. Nonetheless, right-skewed size-frequency distributions for two species of fossil invertebrates give strong indication that this assemblage is a fossil community. This conclusion is supported by the fact that the elongated shells show no tendency toward parallel alignment and the absence of primary sedimentary structures indicative of deposition from strong directional currents.
Echocardiographic assessment of common atrioventricular canal

Abstract Common atrioventricular (AV) canal consist of a group of structural heart malformations that share some common features but can vary widely with respect to anatomic features and physiologic manifestations. High quality, non-invasive evaluation can define the anatomic features of the disease and give cardiologists a full appreciation of the hemodynamic issues. Patients with common AV canal frequently require surgical intervention and the importance of non-invasive evaluation in the intra-operative, peri-operative and post-operative periods has grown along with the technology. Echocardiographic technology has progressed rapidly over the last 25 years, revolutionizing the evaluation of structural heart disease. Patients with suspected common AV canal can now be completely evaluated non-invasively in most cases. Using two-dimensional imaging, color and spectral Doppler, the cardiologist can fully assess cardiac anatomy, hemodynamics and ventricular function. The smaller, high resolution transducers introduced in recent years allow for excellent imaging in newborns. The availability of small transesophageal transducers has made intraoperative study available to patients as small as 2.5 kg. The contribution of three-dimensional echocardiography is still in the investigational stages, but it is likely that it will be important for the further delineation of valve anatomy and for the quantitative assessment of valve and ventricular function. This article reviews the current use of echocardiography in the evaluation of common AV canal, including the initial diagnostic evaluation as well as the intra-operative, post-operative and prenatal evaluation.
Stress recovery in geometrically nonlinear membranes by a Hu-Washizu finite element formulation

A class of mixed finite elements based on the Hu-Washizu functional is introduced as a strategy to reduce the spurious stress phenomena encountered with standard or displacement-based formulations for geometrically exact membranes. Selected examples compare the performance of this class of elements with that of the standard formulation and demonstrate that reduction of spurious stresses is obtained and that the stresses are more accurate than those optimally sampled in the standard formulation.
Occupational Health and Safety in Household Hazardous Waste Management Facilities

Employees in household hazardous waste management facilities encounter a variety of potentially hazardous exposures. The purpose of this study was to evaluate both chemical and physical hazards at a representative group of household hazardous waste management facilities in Minnesota. Sampling results suggest that chemical exposures are generally not a problem when chemical bulking is performed outside the facility. For facilities operating year-round, however, proper ventilation is necessary to ensure adequate control of chemical exposures when bulking is done inside the building. The most significant chemical exposures occurred when handling paint (benzene) and broken fluorescent light bulbs (mercury). Guidelines for appropriate personal protective equipment and handling of broken fluorescent light bulbs were developed as a result of this study. Materials handling was the most significant physical hazard, resulting in wrist, elbow, and back injuries. The suspected reasons for these injuries (awkward postures and repetitive motions) were noted throughout the management process and should be further investigated.
Depletion of high-energy carriers in YAG optical ceramic materials

The scintillation properties of YAG:Ce transparent ceramic material prepared by a hot-pressing technique have been characterized and compared with those of a chemically identical specimen of single crystal. Each of the scintillation steps (conversion, energy transfer and luminescence) has been selectively investigated using appropriate spectroscopic techniques. The light output from the ceramic specimen was measured at approximately 1500 photons/MeV, only 10% of that from the single crystal. This drastic decrease in the ceramic reflects the inefficient transfer of energy from the excited host to the Ce ion. The inefficiency can be attributed to the presence in the ceramic material of a high population of lattice defects, as demonstrated by the UV absorption spectra. Thermoluminescence experiments show that these defects can serve as sinks for free carriers (electrons and holes), providing sites for their nonradiative recombination and preventing them from conveying their energy to the emitting centers.
Zirconocene-promoted synthesis of substituted tetrahydropyrans

Zirconocene reagents derived from zirconocene dichloride and two equivalents of butyllithium react with allylic, homoallylic diene ethers. Hydrolysis of the reaction products yields substituted tetrahydropyrans. The reaction is postulated to occur via cyclization of the diene to form a zirconacyclopentane. This cyclization occurs without allylic rearrangement.
Factors in Development and Adoption of New Cloud Software and Standards

As cloud services increasingly become part of how we do business and solve problems in computing, it's becoming important to evaluate rigorously in real time the level of success of different approaches. This column explores the process of selecting cloud software and standards in modern deployment environments and calls out some important characteristics specific to cloud computing.
Maintenance of Nitric Oxide and Redox Homeostasis by the Salmonella Flavohemoglobin Hmp

Intracellular pathogens must resist the antimicrobial actions of nitric oxide (NO·) produced by host cells. To this end pathogens possess several NO·-metabolizing enzymes. Here we show that the flavohemoglobin Hmp is the principal enzyme responsible for aerobic NO· metabolism by Salmonella enterica serovar typhimurium. We further show that Hmp is required for Salmonella virulence in mice, in contrast to S-nitrosoglutathione reductase, flavorubredoxin, or cytochrome c nitrite reductase. Abrogation of murine-inducible NO· synthase restores virulence to hmp mutant bacteria. In the presence of nitrosative stress, Hmp-deficient Salmonella exhibits reduced NO· consumption, impaired growth, increased protein S-nitrosylation, and filamentous morphology. However, under aerobic conditions in the absence of nitrosative stress, elevated hmp expression increases S. typhimurium susceptibility to hydrogen peroxide. Both the heme binding and flavoreductase domains are required for resistance to NO·, whereas the flavoreductase domain is responsible for iron-dependent susceptibility to oxidative stress. This provides a rationale for the regulation of hmp expression by the transcriptional repressor NsrR in response to both nitrosative stress and intracellular free iron concentration. The Hmp flavohemoglobin plays a central role in the response of Salmonella to nitrosative stress but requires precise regulation to avoid the exacerbation of oxidative stress that can result if electrons are shuttled to extraneous iron.
Effects of metabolic deprivation on methotrexate transport in L1210 leukemia cells: Further evidence for separate influx and efflux systems with different energetic requirements

Measurements of methotrexate transport in L1210 cells in the presence and absence ofd-glucose reveal that both influx and efflux are depressed in the absence ofd-glucose, whereas the steady-state accumulation of drug is enhanced. The reason for the increase in steady state is that the relative decline in efflux is greater than the decline in influx. Analysis of the concentration dependence of steady-state methotrexate accumulation ind-glucose-deprived cells indicates a linear relationship consistent with a one-carrier active transport model. Similar data in nondeprived cells is highly nonlinear and strongly supports the postulate that under physiological conditions influx and efflux of methotrexate are mediated by separate carrier systems. These results indicate that the efflux system, preferentially transporting methotrexate under normal conditions, cannot operate in the absence ofd-glucose, whereas the influx system is only partially inhibited under conditions of glucose deprivation.
Interactions of ethanol and quinidine on contractility and myocyte action potential in the rat ventricle

The combined effects of ethanol and quinidine on cardiac electromechanical coupling are unknown, but both drugs affect cardiac conduction and can cause myocardial depression. Isolated left ventricular papillary and ventricular myocytes were used to assess the combined effects of quinidine and ethanol on the electrophysiologic and mechanical properties of rat myocardium. The combination of quinidine (1-300 microM) and ethanol (120-240 mg/dL) depressed active papillary muscle tension within the clinically useful concentration range. In electrophysiologic studies of isolated ventricular myocytes, quinidine prolonged the action potential duration at 50% (APD50) and 90% (APD90) repolarization, the absolute refractory period, and the relative refractory period, but decreased the maximum rate of change of depolarization in phase 0 (Vmax). When cells were exposed to ethanol (240 mg/dL) and quinidine (1.5 microM) together, a significant decrease in the quinidine-induced prolongation of the absolute refractory and relative refractory periods was seen. Additional changes in action potential parameters from the quinidine values included slight reductions in Vmax and in APD50 and APD90, but these reductions were not consistently displayed, nor were they statistically significant.
Exercising Managerial Prerogatives: The Findings of Four Field Studies

Competitive pressures in the 1980s instigated a wave of managerial initiatives designed to cut costs, loosen work rules, and tighten discipline. Because previous field research on the day-to-day give-and-take between management and labor was done in an era in which unions were the moving force, a void exists in the literature. Described here are four field studies on managers exercising their prerogatives between formal collective-bargaining negotiations. These patterns of behavior are compared to the adversarial and cooperative models that prevail in the fields of industrial relations and organization behavior. Rather than resembling either one model or the other, these case studies reflect a continuum of behavior. Since many people in the academic and managerial communities define "cooperative" and "adversarial" strategies somewhat differently, further research in mis area seems warranted, [management prerogatives, discipline, grievance procedure, fractional bargaining, negotiation]
Synchronous and opposite roles of the parietal and prefrontal cortices in bistable perception: a double-coil TMS-EEG study.

Bistable perception occurs when a stimulus is ambiguous and has two distinct interpretations that spontaneously alternate in observers' consciousness. Studies using functional magnetic resonance imaging, electroencephalography (EEG), and transcranial magnetic stimulation (TMS) in healthy subjects and patient studies point towards a right fronto-parietal network regulating the balance between percept stabilization and the arising of alternative interpretations. However, the causal role of the interaction between parietal and prefrontal areas is not clearly understood. Using intermittent presentations of bistable images, we confirmed that maintaining or switching percepts had neural correlates identifiable on EEG. Single-pulse TMS applied over the right anterior intraparietal sulcus (IPS) 70 msec before image presentation interfered with evoked potentials and destabilized the percept. However, with paired-pulse TMS applied over right IPS and dorsolateral prefrontal cortex (DLPFC) 70 and 60 msec before image presentation, both perceptual and neurophysiological effects were canceled. Thus, TMS over IPS and DLPFC interacted with each other and influenced upcoming percepts. We suggest that when the visual world is ambiguous, IPS plays a stabilizing role, whereas DLPFC is important for triggering perceptual switches or for modulating parietal activity. The balance between maintaining and switching visual conscious percepts relies on the dynamic interaction between IPS and DLPFC.
Muscle fibers from senescent mice retain excitation–contraction coupling properties in culture

In the present study, we test the hypothesis that mouse skeletal muscle in culture retains the fundamental properties of excitation-sarcoplasmic reticulum Ca2+ release coupling reported for young-adult (3–4 mo) and senescent (22–23) mice. Dissociated flexor digitorum brevis (FDB) muscles from young-adult and senescent mice were cultured for 7 d in a serum-free medium. During this period, the overall morphology of cultured fibers resembled that exhibited by acutely dissociated cells. In addition, survival analysis revealed that more than 70% of the fibers from both young and old mice remained suitable for electrophysiological studies during this same culture period. Charge movement and intracellular Ca2+ recordings in FDB fibers, voltage clamped in the whole cell configuration of the patch-clamp technique, reproduced the maximal values, and voltage dependence similarly displayed by acutely dissociated cells for both parameters in young-adult and senescent mice. The analysis of the dihydropyridine receptor by immunoblots confirmed, in the culture system, the age-dependent decrease in the expression of this protein. In conclusion, FDB fibers from young-adult and old mice retain the excitation–contraction coupling phenotype during the course of a week in serum-free medium culture.