cssi/SciSciGPT-SciSciNet huggingface dataset:
Dysregulation of mammalian target of rapamycin pathway in plasmacytoid variant of urothelial carcinoma of the urinary bladder.

Summary Plasmacytoid urothelial carcinoma is a rare but aggressive variant of bladder cancer with no clear therapeutic guidelines. Dysregulation of the mammalian target of rapamycin (mTOR) pathway has been linked to oncogenesis in conventional bladder cancer. Several antineoplastic agents targeting mTOR pathway are currently available. This study assesses mTOR pathway status as well as c-myc and p27 expression. We retrieved 19 archival cases of plasmacytoid urothelial carcinoma from two institutions. Whole tissue sections were evaluated for immunoexpression of phosphatase and tensin homolog (PTEN), phosphorylated mTOR, phosphorylated protein kinase B (AKT), phosphorylated S6, c-myc, and p27. We evaluated intensity (0 to 3+) and extent (0%–100%) of expression for all markers. An H score was calculated as the sum of products of intensity and extent for each marker and used during analysis. In addition, PTEN loss was defined as absence of expression in >10% of tumor cells. We encountered PTEN loss in 28%. Higher H score for nuclear phosphorylated AKT and a lower H score for phosphorylated S6 was encountered in muscle invasive tumors compared to non-muscle invasive tumors ( P = .007 and P = .009, respectively). Although a trend for negative prognostic impact on overall survival for higher phosphorylated mTOR expression was noted ( P = .051), markers expression levels failed to predict survival in our cohort. We found dysregulation of mTOR pathway members in urinary bladder plasmacytoid urothelial carcinoma, suggesting that the use of mTOR pathway inhibitors might be beneficial for patients with this aggressive tumor.
CD4+ T cells, without CD8+ or B lymphocytes, can reject xenogeneic skin grafts

: Previous experiments have shown that rejection of xenogeneic skin grafts by mice is particularly dependent on CD4+ T cells. There are two possible explantations for this finding: either 1) “help” provided by CD4+ T cells is essential for CD8+ T cell-, B cell-, or NK cell-mediated effector mechanisms of rejection, or 2) CD4+ cells are themselves responsible for rejection, perhaps by some nonspecific effector mechanism. To examine these two hypotheses, we transplanted pig skin onto SCID mice and then reconstituted the mice with selected subpopulations of lymphocytes. Mice that did not received CD4+ T cells were unable to reject their xenografts, whereas those receiving CD4+ cells could do so in the absence of CD8+ cells or B cells and even when additionally depleted of NK cells by treatment with anti-Asialo GM1 antibody. Additional experiments were performed both in vivo and vitro to confirm the absence in test mice of CD4+ or CD8+ and B lymphocytes, respectively. These results suggest that CD4+ T cells are not only necessary for rejection of xenogeneic skin grafts by mice, but that they can do so without CD8+ cells or B cells, and probably without NK cells. Since CD4+ cells in mice have been shown to recognize xenogeneic antigens indirectly, this suggests that a nonspecific effector mechanism may be involved in the rejection of xenografts. In these experiments allogeneic skin grafts behave quite differently as they could not be rejected by this mechanism.
Tissue–Tissue Interactions During Morphogenesis of the Outflow Tract

The heart forms as a linear heart tube that loops and septates to produce a mature four-chambered structure. The single vessel emerging from the embryonic heart, the truncus arteriosus, divides into the aorta and the pulmonary artery as part of this septation process, and a series of additional morphogenetic events result in the proper alignment and orientation of the cardiac outflow tract. Recent evidence indicates that this process involves the complex interactions of multiple cell types including primary and secondary heart fields, neural crest, pharyngeal mesenchyme, endoderm, and endothelium. Among the many signals that mediate tissue–tissue interactions during the formation of the outflow tract, we have focused on the role of the Notch signaling pathway. Here, we focus on recent advances in our understanding of Notch-mediated regulation of cardiac development with specific attention to the formation of the cardiac outflow tract.
Effect of the APOE Polymorphism and Age Trajectories of Physiological Variables on Mortality: Application of Genetic Stochastic Process Model of Aging.

We evaluated effects of the APOE polymorphism (carriers versus noncarriers of the e4 allele) and age trajectories of total cholesterol (CH) and diastolic blood pressure (DBP) on mortality risk in the Framingham Heart Study (original cohort). We found that long-lived carriers and noncarriers have different average age trajectories and long-lived individuals have consistently higher levels and less steep declines at old ages compared to short-lived individuals. We applied the stochastic process model of aging aimed at joint analyses of genetic and nongenetic subsamples of longitudinal data and estimated different aging-related characteristics for carriers and noncarriers which otherwise cannot be evaluated from data. We found that such characteristics differ in carriers and noncarriers: (1) carriers have better adaptive capacity than noncarriers in case of CH, whereas for DBP the opposite situation is observed; (2) mean allostatic trajectories are higher in carriers and they differ from “optimal” trajectories minimizing mortality risk; (3) noncarriers have lower baseline mortality rates at younger ages but they increase faster than those for carriers resulting in intersection at the oldest ages. Such observations strongly indicate the presence of a genetic component in respective aging-related mechanisms. Such differences may contribute to patterns of allele- and sex-specific mortality rates.
Effect of nickel particle size on the compaction behavior of rotator mixed and mechanically alloyed nickel and aluminum powders

Elemental powder mixing prior to processes such as self-propagating high temperature synthesis (SHS) is a vital processing step that needs careful consideration. This is particularly true for powders with submicron particle sizes. The present paper investigates the effect of mechanical alloying of mixtures of aluminum and nickel (with different nickel particle sizes) on the dispersion and cold compaction behavior of the composite powders. The concepts of the theory of plasticity of porous bodies are also employed to assess the influence of mechanical alloying (MA) on the theoretical yield stress of the composite powder compact. It was found that after mechanical alloying, the yield stress increased only for nickel powder sizes equal to and greater than 5 μm.
A new antegrade ureteral stent.

This simple 6-F, antegrade ureteral catheter can be used for various endourologic procedures and the radiopaque band allows for easy visualization, with either fluoroscopy or routine x-ray films
Germ cell degeneration and intercellular bridges in the human fetal ovary.

Intercellular bridges between developing germ cells were observed in human fetal ovaries at 10 to 20 weeks gestation. Bridges were frequently found between cells in early stages of degeneration, with similar regressive changes being present in the conjoined cells. In advanced stages of cellular degeneration, bridges were less frequently found and were generally distorted and partially disrupted. Similarity in appearance of adjacent degenerating cells was common, even in late stages of degeneration. These observations suggest that cellular interconnection may be responsible for synchronous degeneration of germ cells during oogenesis.
Introduction to ocean optics

In this introductory survey of optical oceanography, the fundamental inherent and apparent optical properties of natural waters are presented. Relationships between these inherent and apparent optical properties, as related through the radiative transfer equation, are then examined. Following the first three theoretical sections, brief discussions describing the application of ocean optics to geophysics, biological oceanography, and ocean remote sensing are then presented.
Application of the Hückel-Möbius concept to torsional vibration and internal rotation of molecules

Abstract The geometrical foundation of the Huckel—Mobius concept is discussed. To extend the application of these concepts, linear combinations of vibrational wavefunctions (LCVW) centered at the periodic potential minima are used to represent the approximate torsional wavefunction of the hindered internal rotation of a coaxial-(XYn)2-type molecule. These linear combinations are shown to have the correct pseudo-angular momentum upon rotation of either one or both parts of the rotor, and they are uniquely correlated with the wavefunctions of free internal rotation having the same angular momentum. It is shown that if 2n-potential minima are used, Huckel combination yields even, whereas Mobius combination yields odd internal angular momentum ki and they necessarily combine, respectively, with the even and odd overall rotation quantum number K. If n-fold instead of 2n-fold symmetry and Cin rotation are used, the same Huckel and Mobius combinations give, respectively, integral and half-integral angular momentum j (= ki/2) and form the complete irreducible representations of the C′n double group. Making use of the sign variation of the “resonance” interaction integral with different vibrational levels, we construct Huckel—Mobius energy levels that form the cluster of properly alternating non-degenerate and degenerate levels for the high-barrier case. The level patterns reproduce the results of the spectroscopic double-group treatment of dimethylacetylene by Bunker and Hougen and of ethane by Hougen. The general energy constructs also predict the torsional splitting pattern of molecules of higher different-fold symmetries and are used to illustrate the case of disulphur decafluoride with 4-fold static symmetry and with 8 torsional minima. It is contended that by invoking 2n-fold symmetry for the motion of a statically n-fold symmetric system, one obtains a three-dimensional example of half-integral (pseudo) angular momentum normally seen only in relativistic spin space. One also provides a molecular analogy of a true Mobius ring. Using Franck—Condon overlaps, a demonstration of the cause for sign variation of the “resonance” interaction integral with vibrational level in the case of C2H6 and S2F10 is given. An estimate of the ratio of tunneling probabilities for the first four vibrational levels is also given. These ratios give correct order-of-magnitude agreement with experimental data for ethane.
The impact of energy production on human health

Private industry is properly concerned with the prevention of disease and the maintenance and promotion of health of employees, as well as the health of consumers as affected by its products, and the health of the community as it is affected by the industry. To operate responsibly, industry critically needs scientific information in each of these areas. And, it follows that industry's involvement in the generation, communication, and use of scientific information is obligatory. The petroleum industry represents a dominant form of energy for the nation. A thorough evaluation of its health relationships is important not only in its own right, but also because the petroleum industry can serve as a basis for comparison with other energy sources, especially the new and alternate resources to be developed in the future. To view in perspective industry's role in handling health-related information, a number of examples from the petroleum industry wich deal with the occupational health status of employees are presented. The areas of industry's impact upon the health consumers and community health, while equally important, are considered more briefly. Finally, certain inappropriate devices are pointed out, which - when applied to the derivaton and utilization of scientific information - ill servemore » the scientific community and the public, with particular reference to regulatory processes.« less
Using a macroalgal δ15N bioassay to detect cruise ship waste water effluent inputs

Green macroalgae bioassays were used to determine if the δ15N signature of cruise ship waste water effluent (CSWWE) could be detected in a small harbor. Opportunistic green macroalgae (Ulva spp.) were collected, cultured under nutrient depleted conditions and characterized with regard to N content and δ15N. Samples of algae were used in controlled incubations to evaluate the direction of isotope shift from exposure to CSWWE. Algae samples exposed to CSWWE exhibited an increase of 1-2.5‰ in δ15N values indicating that the CSWWE had an enriched isotope signature. In contrast, algae samples exposed to field conditions exhibited a significant decrease in the observed δ15N indicating that a light N source was used. Isotopically light, riverine nitrogen derived from N2-fixing trees in the watershed may be a N source utilized by algae. These experiments indicate that the δ15N CSWWE signature was not detectable under the CSWWE loading conditions of this experiment.
THE STRUCTURE AND DIFFERENTIATION OF THE SPECIFIC CELLULAR ELEMENTS OF THE PARS INTERMEDIA OF THE HYPOPHYSIS OF THE DOMESTIC PIG

The bearing of these results on the Herring-Cushing theory of pituitary secretion is apparent. For the first time a true secretion antecedent has been demonstrated in the cells of the pars intermedia, an antecedent which appears in the cells at the same period of development at which active pressor effects may be obtained from the gland extracts. The route of export of this material from the gland to its point of utilization, however, is unknown; it may go by way of the blood or, as required by the Herring theory, by the transneural route to the third ventricle. The objections to the latter conclusion have been amply expanded in the introduction to this paper, but here may be emphasized the fact that the fetal pig hypophysis contains no hyaline bodies. Indeed they are rare in the adult, though there may be seen in the cells of the pars nervosa in the processes of its intrinsic cells, granular deposits which we believe to be the antecedents of the hyaline bodies but which in the pig rarely are discharged and aggregated into discrete masses as in other mammals. The fact that some observers have obtained positive pressor effects from the nervous part of the posterior lobe, exclusive of the pars intermedia, need not weigh very heavily in attempting to trace the course of the secretion, when we reflect that the difficulties of making such a mechanical separation are almost insuperable, and that the chemical product of the pars intermedia is so soluble and vanishes from the cells so rapidly that it may well be diffusible through the thin membranes which intervene and penetrate post mortem into adjacent parts. We are inclined, therefore, to the view that the secretion leaves the gland by the vascular route rather than by way of the interfibrillar spaces of the pars nervosa.
Novel phenotypes arising from selection of hamster melanoma cells for resistance to BUdR.

Abstract Pigmented clones of the Syrian hamster melanoma line RPMI 3460 were selected for resistance to high levels of the thymidine analogue 5-bromodeoxyuridine (BUdR). The resistant lines obtained were characterized as to the percentage of thymidine residues in nuclear DNA replaced by BUdR (BUdR substitution), the level of in vitro thymidine kinase (EC 2.7.1.75) (TK) activity the ability to utilize exogenous thymidine for growth, and pigmentation. In contrast to the BUdR resistant cells generally reported in the literature, most of the lines isolated in this study have large amounts of BUdR in their nuclear DNA and/or high levels of TK activity. The ability of the cells to utilize exogenous thymidine was found to correlate well with the level of BUdR substitution. However, there was a definite lack of correlation between the level of in vitro TK activity and the level of BUdR-substitution. Further, the phenotypes of the cells selected in 10−4 M BUdR appear to be to some extent clonally determined.
ECG screening for athletes: letting evidence and reason advance the debate.

s d Sudden cardiac death (SCD) in a young athlete, usually due to genetic cardiovascular disease, is a tragic and emotionally charged event that brings to the forefront the ongoing debate about preparticipation electrocardiographic (ECG) screening and athletic restriction. Development of a cost-effective screening strategy with a high predictive accuracy in detecting cardiovascular conditions predisposing to SCD in athletes is an intuitively attractive public heath priority. The primary objective of preparticipation athetic screening is detection of potentially lethal cardiovasular diseases likely to manifest as SCD during athletics. In taly, a 12-lead ECG is routinely obtained as part of a andatory comprehensive screening program. This systematic screening is associated with a decline in deaths when linked to athletic restriction. Since 1982, this government-subsidized national screening program with ECGs has been performed at regional centers by highly specialized physicians with legal liability for errors. In contrast, the ustomary practice of screening athletes in the United States s limited to history and physical examination performed by wide range of health care professionals with varying xpertise without routine inclusion of an ECG in a less ccountable legal context. Although other European countries have adopted the Italian model and some experts have suggested that ECG screening should be added for U.S. athletes, considerable controversy remains regarding this approach. Despite any studies evaluating the outcomes of preparticipation creening, few have evaluated the incremental value and cost f ECG to the standard screening history and physical examnation. Because the outcomes and cost of screening with ECG remain incompletely studied, many experts believe that data are insufficient to justify a U.S. national program similar to that used in Italy. Issues related to cost effectiveness, false-positive screening tests, and the efficacy of athletic restriction in preventing SCD are particular concerns. The problem with borderline or false-positive test results, commonly from ECG interpretation, is particularly relevant
Steps linking the photosynthetic light reactions to the biological clock require calcium.

The effect of modifying calcium concentration on the expression of the photosynthesis circadian rhythm was examined in Euglena gracilis, Klebs strain Z. Expression of the oxygen evolution rhythm required the presence of both extracellular and intracellular calcium. Several treatments were found to uncouple the rate of the light reactions from the biological clock. In the presence of these chemical agents, the rate of oxygen evolution increased steadily throughout the light portion of the light/dark cycle, instead of showing a peak of activity in the middle of the light cycle. Oxygen evolution was uncoupled from the biological clock when extracellular calcium concentrations were altered by the presence of EGTA or LaCl3. Uncoupling was also observed when intracellular calcium concentrations were disrupted by the use of Ca2+ channel blockers, the intracellular Ca2+ antagonist 8-(diethylamino)-octyl-3,4,5-trimethoxybenzoate, or by disrupting expression of the inositol trisphosphate system. Uncoupling was also observed when the diacylglycerol signaling system, which activates kinase C, was inhibited by acridine orange. The inhibition was reversed by the presence of phorbol esters which activate the kinase. It was concluded that both the inositol trisphosphate and diacylglycerol signaling systems were required for the expression of the oxygen evolution rhythm generated by the biological clock.
Interactive effect of salinity and Verticillium albo-atrum on verticillium wilt disease severity and yield of two alfalfa cultivars

The interaction between the fungus Verticillium albo-atrum and soil salinity was evaluated for two alfafa (Medicago sativum cultivars, Moapa-69 and NK-89786, differing in susceptibility to Verticillium wilt. Salinity treatments (NaCL, CaCl2) were imposed by drip irrigation of 7-week-old plants which were then inoculated by soil drench with different concentrations of V. albo-atrum. In the absence of V. albo-atrum, a salinity of 7.5 dS/m significantly (P<0.05) reduced yield of both cultivars relative to the nonsaline control. Thresholds for reduction in relative yield with increasing salinities were 0.8 for NK-89789 and 1.6 dS/m for Moapa-69, indicating that NK-89786 was more sensitive to salinity than Moapa-69. In the absence of salinity, the percentage of stems infected with V. albo-atrum and the severity of root xylem necrosis were significantly greater for Moapa-69 than for NK-89786. Inoculation with V. albo-atrum did not significantly reduce yield of either cultivar when grown in nonsaline soil; however, when infected NK-89786 plan ts were irrigated with salin e water of 3.0, 5.0, or 7.5 dS/m, yield was significantly reduced relative to yield loss due to the effects of V. albo-atrum inoculation alone. A similar yield reduction occurred for Moapa-69, but only at 7.5 dS/m.
Role of vacuolar adenosine triphosphatase in the regulation of cytosolic pH in hepatocytes.

The responses of the cytosolic pH of hepatocytes in suspension to agents affecting the activity of vacuolar adenosine triphosphatase (V-ATPase) and Na/H exchange have been studied. Changes of cytosolic pH were determined both with dual-wavelength excitation (500/440 nm) of the fluorescence of 2′,7′-bis-(2-carboxyethyl)-5(and 6)-carboxyfluorescein and from the distribution of 14C-dimethyloxazolidinedione; both methods gave very similar results. Changes of vesicular pH were determined by comparing the fluorescence of fluorescein isothiocyanate-dextran and rhodamine B isothiocyanate-dextran taken up by endocytosis. Nitrate, which inhibits V-ATPase in isolated organelles, induced a concentration-dependent acidification of the cytosol and alkalinization of vesicles, with maximal effects at 25–37.5 mm in each case, indicating that V-ATPase contributes to removal of cytosolic protons. On continued exposure to nitrate, the acidification underwent an amiloride-inhibitable reversal. At the higher concentrations of NO3−, both cytosolic acidification and vesicular alkalinization were reduced or absent. Bafilomycin A1 caused alkalinization of vesicular pH; cytosolic acidification was not observed, possibly because of other ionic exchanges. Recovery of cytosolic pH from an acid load (2 min exposure to 5% CO2) was sensitive to both 25 mm NO3−and to ouabain. The pH dependence of the nitrate effect was tested with media of different pH; the activity was negligible at cytosolic pH 6.2 and rose to a maximum at cytosolic pH 7.3. Treatment of hepatocytes with 0.5–1.0 mm ouabain resulted in an initial alkalinization (0.5–2 min duration) of the cytosol, followed by a spontaneous reversal and, on occasion, further acidification. The alkalinization was blocked by 25 mm NO3−, but not by 25 mm gluconate. The results suggest that the cytosolic alkalinization is caused by a stimulation of H+ uptake by V-ATPase activity. We conclude that V-ATPases make an important contribution to the regulation of the cytosolic pH of hepatocytes.
Induction and Persistence of Abnormal Testicular Germ Cells Following Gestational Exposure to Di-(n-Butyl) Phthalate in p53-Null Mice

Phthalate esters are commonly used plasticizers found in many household items, personal care products, and medical devices. Animal studies have shown that in utero exposure to di-(n-butyl) phthalate (DBP) within a critical window during gestation causes male reproductive tract abnormalities resembling testicular dysgenesis syndrome. Our studies utilized p53-deficient mice for their ability to display greater resistance to apoptosis during development. This model was chosen to determine whether multinucleated germ cells (MNG) induced by gestational DBP exposure could survive postnatally and evolve into testicular germ cell cancer. Pregnant dams were exposed to DBP (500 mg/kg/day) by oral gavage from gestational day 12 until birth. Perinatal effects were assessed on gestational day 19 and postnatal days 1, 4, 7, and 10 for the number of MNGs present in control and DBP-treated p53-heterozygous and null animals. As expected, DBP exposure induced MNGs, with greater numbers found in p53-null mice. Additionally, there was a time-dependent decrease in the incidence of MNGs during the early postnatal period. Histologic examination of adult mice exposed in utero to DBP revealed persistence of abnormal germ cells only in DBP-treated p53-null mice, not in p53-heterozygous or wild-type mice. Immunohistochemical staining of perinatal MNGs and adult abnormal germ cells was negative for both octamer-binding protein 3/4 and placental alkaline phosphatase. This unique model identified a role for p53 in the perinatal apoptosis of DBP-induced MNGs and provided insight into the long-term effects of gestational DBP exposure within a p53-null environment.
Dopamine increases in striatum do not elicit craving in cocaine abusers unless they are coupled with cocaine cues.

Abstract Imaging studies have shown an association between dopamine increases in striatum and cue induced craving in cocaine abusers. However, the extent to which dopamine increases reflect a primary rather than a secondary response to the cues remains unclear. Here we evaluated the extent to which dopamine increases by themselves can induce craving in cocaine abusers. Using PET and [11C]raclopride (D2 receptor radioligand sensitive to competition with endogenous dopamine) we show that in cocaine abusers (n = 20) oral methylphenidate (20 mg), which significantly increased dopamine in striatum, did not induce craving unless subjects were concomitantly exposed to cocaine cues (video scenes of subjects self-administering cocaine). This suggests that dopamine increases associated with conditioned cues are not primary responses but reflect downstream stimulation of dopamine cells (presumably glutamatergic afferents from prefrontal cortex and/or amygdala). Inasmuch as afferent stimulation of dopamine neurons results in phasic cell firing these findings suggest that “fast” dopamine increases, in contrast to the “slow” dopamine increases as achieved when using oral methylphenidate (mimicking tonic dopamine cell firing), are required for cues to trigger craving. The fact that methylphenidate induced craving only when given with the cocaine cues highlights the context dependency of methylphenidate’s effects and suggests that its use for the treatment of ADHD subjects with co-morbid drug abuse should not increase craving.
Vanadate-Mediated Hydroxyl Radical Generation from Superoxide Radical in the Presence of NADH: Haber-Weiss vs Fenton Mechanism

Abstract The mechanism of hydroxyl (·OH) radical generation from O−2 and H2O2 by vanadate [V(V)] and the role of NADH in this reaction have been investigated using electron spin resonance (ESH) and spin trapping techniques. The results show that the reaction of V(V) with O−2 (generated via xanthine/xanthine oxidase) does not generate any ESR detectable V(IV) ion or ·OH radical and the addition of H2O2 has little effect on the radical yield. In the presence of NADH, however, the xanthine/xanthine oxidase/V(V) system generates ·OH as well as V(IV), the formation of both of which could be suppressed by superoxide dismutase. Catalase inhibits the ·OH formation but enhances V(IV) generation. Reaction of V(V) with NADH alone in the presence of phosphate buffer also causes ·OH radical generation albeit at a much reduced rate, and superoxide dismutase reduces the ·OH yield. These observations indicate, in contrast to earlier reports, that O−2 does not reduce V(V) to V(IV) in the absence of NADH. It is concluded that vanadate generates the ·OH radical via not a Haber-Weiss but a Fenton-like reaction [V(IV) + H2O2 → V(V) + ·OH + OH−], the V(IV) and H2O2 being generated by V(V)-stimulated, O−2-dependent NADH oxidation.
Meeting People Where They Are: Recognizing Early Educators’ Readiness to Change

When it comes to changing one's behavior, what makes a person ready to change? In this study, mentors participated in interviews and focus groups about early childhood educators’ readiness to change their practices with children. One third of the educators were rated by their mentors as “not ready to change” as measured by the Stage of Change Scale 1.0. The interviews and focus groups identified common features of educators who were not ready to change as well as mentors’ strategies and challenges in working with these educators. The article concludes with recommendations for professional development programs as well as a description of the types of skills and practices that may be effective for facilitators.
Failure to obtain admission sputum culture is associated with higher mortality and fewer ventilator-free days for intubated pneumonia patients: a quality improvement project

The primary objective was to assess the impact of failure to obtain sputum culture (SC) among patients requiring intubation for pneumonia. For patients admitted to an ICU with severe pneumonia, guidelines recommend obtaining a lower respiratory tract sample for culture. Our experience suggested this is rarely ordered from the emergency department (ED).
Carbofuran-induced alterations (in vivo) in high-energy phosphates, creatine kinase (CK) and CK isoenzymes.

Male Sprague-Dawley rats administered with an acute sublethal dose of carbofuran (1.5 mg/kg, s.c.) developed the signs of peak hypercholinergic activity during 30-60 min. At this time, in hemidiaphragm muscle, a significant decrease in ATP (28%) and phosphocreatine (PC) (29%) occurred without concurrent change in AMP and creatine (CR). A significant decrease in the levels of total adenine nucleotides (ATP + ADP + AMP) (20%) and total creatine compounds (PC + CR) (17%) was evident. The decline in the corresponding ratios of ATP/ADP (26%), ATP/AMP (39%), and PC/CR (20%) was therefore suggestive of greater utilization of ATP and PC in response to their increased demand for high-frequency muscle fasciculations. The energy charge = ATP + 1/2 ADP/(ATP + ADP + AMP), an index of high-energy phosphate adequacy in hemidiaphragm, remained unchanged. A significant (p less than 0.01) increase in serum magnesium with no concurrent change in calcium was also evident. The observed higher activity (152%) of total CK (EC 2.7.3.2) in the serum induced by carbofuran was possibly a reflection of more than a twofold increase in CK-BB isoenzyme (CK-1) and 141% increase in CK-MM isoenzyme (CK-3), which also strengthens our findings of enhanced synthesis of ATP and PC. Increased levels of CK-MM isoenzyme in the brain (253%) and hemidiaphragm (195%); and depletion of CK-BB isoenzyme in the hemidiaphragm (0%), heart (42%), and brain (77%), and of CK-MB isoenzyme (CK-2) in the brain (4%) and hemidiaphragm (14%), appeared to be the major contributory factors leading to enhanced serum CK activity.
Thinking Sociologically With Mathematics

Affect Control Theory was developed to address some issues in role theory. However, a mathematical formulation allowed the theory to expand rapidly to a variety of substantive issues, such as labeling, attributions, emotions, and the impact of settings on social interaction. Formalization raised theoretical issues that might have been neglected otherwise, and helped in defining the boundaries of the theory. A reasonable lesson to draw from development of affect control theory is that even modest mathematical analyses can expand theoretical productivity.
Statewide Trial‐Heat Polls and the 2000 Presidential Election: A Forecast Model*

Objective. We provide an examination and update of a presidential election forecasting model that we have previously developed to predict state-level presidential election outcomes. Method. Our model consists of September statewide trial-heat polls in 1992, 1996, and 2000 along with a prior vote variable. We use this model to generate predictions for both state-level and national-level outcomes. Results. Although our model generated reasonably accurate point estimates of state-level outcomes in 2000, it still incorrectly predicted a Gore victory in 2000. Conclusions. We discuss possible explanations for the 2000 misprediction and present updated coefficients to be used to generate a forecast for the 2004 election.
Process dependence of perturbative quantum-chromodynamic jet structures

We examine the structure of elementary 2 ..-->.. 3 processes involving leptons, quarks, and gluons, as calculated to lowest nontrivial order in the perturbation series for quantum chromodynamics. Particular attention is devoted to the canonical mass-singularity structure of these perturbative expressions along the borders of phase space, since it is precisely the residues of these poles which yield the asymptotic ratio C/sub 2/(G)/C/sub 2/(R) for the widths of gluon/quark jets. We find, however, that the extent to which this simple pole behavior can be applied in regions of phase space corresponding to observable jet structures is extremely limited. In fact, the perturbative widths for quark jets need not always be narrower than those for gluon jets. Distributions in various jet variables are presented. We find that the three-jet signal in hadronic processes is typically 2 to 4 times larger than in e/sup +/e/sup -/ annihilation.
Evolution of host resistance to parasite infection in the snail-schistosome-human system.

The evolutionary strategies that emerge within populations can be dictated by numerous factors, including interactions with other species. In this paper, we explore the consequences of such a scenario using a host–parasite system of human concern. By analyzing the dynamical behaviors of a mathematical model we investigate the evolutionary outcomes resulting from interactions between Schistosoma mansoni and its snail and human hosts. The model includes two types of snail hosts representing resident and mutant types. Using this approach, we focus on establishing evolutionary stable strategies under conditions where snail hosts express different life-histories and when drug treatment is applied to an age-structured population of human hosts. Results from this work demonstrate that the evolutionary trajectories of host–parasite interactions can be varied, and at times, counter-intuitive, based on parasite virulence, host resistance, and drug treatment.
Ethnicity and socioeconomic status: Impact on the diagnosis of congenital heart disease

Abstract Objectives. The purpose of this study was to estimate the prevalence rates of specific cardiac defects for three ethnic groups and to determine the effects of ethnicity, family income and household education level on the timing of referral for pediatric cardiac care. Background. Previous studies examining ethnic differences in rates of congenital heart disease were based on hospital referrals or were limited to diagnoses made in the 1st year of life. These limitations may lead to potential biases in the ascertainment of cases. The present study is population based and includes patients diagnosed after the 1st year of life. Methods. Cases of congenital heart disease were enumerated among 379,561 liveborn infants to black, white and Mexican-American residents in Dallas County, Texas. Diagnosis was made on the basis of examination by a pediatric cardiologist, two-dimensional echocardiographic studies, cardiac catheterization or observations at operation or at autopsy. Ethnicity, median family income and household educational level were determined from birth certificate information. Results. White children had higher prevalence rates for aortic stenosis, endocardial cushion defect and ventricular septal defect. Mexican-American children had the lowest rate for hypoplastic left heart syndrome. The median age at referral to a pediatric cardiologist was 1.9 months for blacks, 2.1 months for whites and 2.2 months for Mexican-Americans. Stratifying the cases by median family income and household educational level failed to show any significant relation to age at referral. Conclusions. Prevalence rates of specific cardiac defects vary among black, white and Mexican-American children, probably reflecting different genetic and environmental backgrounds. The timing of referral for pediatric cardiac care, however, was not related to ethnicity, median family income or household educational level.
Beta3-integrin–mediated focal adhesion complex formation: adult cardiocytes embedded in three-dimensional polymer matrices

In vivo studies show that beta3-integrin-mediated focal adhesion formation (FAF) causes recruitment of nonreceptor tyrosine kinases to the cytoskeleton in pressure-overloaded myocardium. To define the mechanism of beta3-integrin-mediated signaling, we developed a cell culture model (adult feline cardiocytes embedded in a 3-dimensional matrix of native type 1 collagen, fibronectin, and vitronectin) wherein beta3-integrin-mediated focal adhesion kinase occurs. Focal adhesion kinase was analyzed immunocytochemically using confocal microscopy. Initial studies suggested that cardiocytes cultured in a 3-dimensional matrix formed focal adhesions consisting of both beta3-integrin and the muscle-specific isoform, beta1-integrin (beta1D). The focal adhesions were associated with focal adhesion kinase on both costameres and intercalated disks. To determine the cause of beta1D-integrin-mediated focal adhesion kinase in this model, time course studies were done. Beta3-integrin-mediated focal adhesion kinase occurred within 30 minutes after embedding cardiocytes and persisted for >24 hours, whereas beta1D-integrin-mediated focal adhesion kinase was present from the outset. Because confocal microscopy showed that laminin was present on the surface of freshly isolated cardiocytes, we hypothesized that this was causative of beta1D-integrin-mediated focal adhesion kinase. Freshly isolated cardiocytes washed with acidic medium (2 minutes, pH 3.0) to remove laminin and then embedded in a 3-dimensional matrix showed complete absence of beta1D-integrin-mediated focal adhesion kinase, but beta3-integrin-mediated focal adhesion kinase occurred with a time course similar to that seen in cultured, unwashed cardiocytes. Acid washing did not alter the binding ability of beta1D-integrin, because acid-washed cardiocytes in the presence of laminin showed beta1D-integrin-mediated focal adhesion kinase. Thus, cardiocytes embedded in a 3-dimensional matrix show beta3-integrin-mediated focal adhesion kinase and provide an in vitro model to study beta3-integrin-mediated signaling in response to hemodynamic cardiac loading.
Durability of thoracoabdominal aortic aneurysm repair in patients with connective tissue disorders

Objective: Thoracoabdominal aortic aneurysm (TAAA) repair is a durable procedure performed with reasonable perioperative mortality and morbidity in patients with atherosclerotic aortic disease. However, the long-term outcome and durability of TAAA repair performed in patients with a connective tissue disorder (CTD) is not well known. Methods: The records of 257 patients who underwent TAAA repair at the Johns Hopkins Hospital between January 1992 and December 2001 were reviewed. Survival analysis was performed with Kaplan-Meier analysis, and subgroups were compared with the log-rank test. Multivariable analysis was performed with the Cox proportional hazards model and logistic regression. Results: Patients with CTD (n = 31) were seen earlier (mean age, 48.6 ± 2.9 years) than patients without CTD (mean age, 69.1 ± 0.6 years; P 6 months) deaths in patients with CTD, none were from aortic rupture or dissection, compared with two of 31 late deaths in patients without CTD. Multivariable analysis confirmed that postoperative renal failure (P = .03) predicted mortality but neither CTD (P = .93), nor Crawford extent (P = .21, Cox regression) predicted mortality. Among survivors, no mean difference was found in largest aortic diameter on follow-up imaging in patients with or without CTD (4.7 ± 0.3 cm versus 4.4 ± 0.3 cm; P = .47, Mann-Whitney U test). The cumulative graft patency rate, representing long-term graft stability and with death, rupture, dissection, or recurrent aneurysm as endpoints, was 47.5% ± 4.6% at 5 years (Kaplan-Meier) and was similar in patients with or without CTD (P = .10, log-rank test). Conclusion: TAAA repair appears to be a durable operation, with a reasonable 5-year patient survival rate and a low risk of postoperative paraplegia or additional aortic events. Patients with CTD can expect their outcome, including long-term survival and aortic stability, to be similar to patients without CTD. (J Vasc Surg 2002;36:696-703.)
Similatives and the argument structure of verbs

I begin with the observation in Haspelmath and Buchholz (1998) that languages tend to use the same morpheme to mark the standard of comparison across equation constructions. In English, it is the morpheme as, in similatives like John dancedasSue (did) and equatives like John is as tallasSue (is). The first goal of this paper is to provide an analysis of as that accounts for its distribution across these constructions. The second goal of this paper is to provide an account of Haspelmath and Buccholz’s second observation, which is that while languages can form equatives with parameter markers (PMs; the first as in John isastall as Sue (is)), languages generally do not form similatives with parameter markers. I suggest that equation constructions are a test for lexicalized argumenthood, i.e. that the equation of a non-lexicalized argument prohibits the presence of a PM, and, for English, vice-versa. This leads to the conclusion that, contrary to recent claims (Pinon 2008; Bochnak 2013), verbs, unlike adjectives, generally do not lexicalize degree arguments.
T helper cells in cytotoxic T lymphocyte development: Role of L3T4+-dependent and -independent T helper cell pathways in virus-specific and alloreactive cytotoxic T lymphocyte responses

Abstract I have compared the requirements for T helper (Th) cell function during the generation of virus-specific and alloreactive cytotoxic thymus (T)-derived lymphocyte (CTL) responses. Restimulation of vesicular stomatitis virus (VSV)-immune T cells (VSV memory CTLs) with VSV-infected stimulators resulted in the generation of class I-restricted, VSV-specific CTLs. Progression of VSV memory CTLs (Lyt-1 − 2 + ) into VSV-specific CTLs required inductive signals derived from VSV-induced, Lyt-1 + 2 − Th cells because: (i) cultures depleted by negative selection of Lyt-1 + T cells failed to generate CTLs; (ii) titration of VSV memory CTLs into a limiting dilution (LD) microculture system depleted of Th cells generated curves which were not consistent with a single limiting cell type; (iii) LD analysis of VSV memory CTLs did produce single-hit curves in the presence of Lyt-1 + 2 − T cells sensitized against VSV; and (iv) monoclonal anti-L3T4 antibody completely abrogated CTL generation against VSV. Similar results were also obtained with Sendai virus (SV), a member of the paramyxovirus family. The notion that a class II-restricted, L3T4 + Th cell plays an obligatory role in the generation of CTLs against these viruses is also supported by the observation that purified T cell lymphoblasts (class II antigen negative) failed to function as antigen-presenting cells for CTL responses against VSV and SV. T cell lymphoblasts were efficiently lysed by class I-restricted, anti-VSV and -SV CTLs, indicating that activated T cells expressed the appropriate viral peptides for CTL recognition. Furthermore, heterogeneity in the VSV-induced Th cell population was detected by LD analysis, suggesting that at least two types of Th cells were required for the generation of an anti-VSV CTL response. VSV-induced Th cell function could not simply be replaced by exogenous IL-2 because this lymphokine induced cytotoxic cells that had the characteristics of lymphokine-activated killer (LAK) cells and not anti-viral CTLs. In contrast, CTL responses against allogeneic determinants could not be completely blocked with antibodies against L3T4 and depletion of L3T4 + cells did not prevent the generation of alloreactive CTLs in cultures stimulated with allogeneic spleen cells or activated T cell lymphoblasts. Thus, these studies demonstrate an obligatory requirement for an L3T4-dependent Th cell pathway for CTL responses against viruses such as VSV and SV; whereas, CTL responses against allogeneic determinants can utilize an L3T4-independent pathway.
An investigation of isomeric differences in hydrolytic rates of oxazolidines using computational methods

Abstract The mechanism of hydrolysis of diastereomeric oxazolidines formed by the reaction of (−)-ephedrine and (+)-pseudoephedrine with formaldehyde was studied using semiempirical and ab-initio methods. (−)-Ephedrine forms a cis-oxazolidine, while (+)-pseudoephedrine forms a trans-oxazolidine. cis-Oxazolidines have been observed to hydrolyze more rapidly than trans-oxazolidines in neutral or basic solution. The structures of all intermediates in the proposed reaction mechanism were optimized using AM1, Hartree–Fock and MP2 levels of theory. Vibrational frequencies were calculated at the Hartree–Fock level of theory in order to obtain zero-point energies. The enthalpy change of each reaction step was calculated from these data. Enthalpy differences between cis- and trans-isomers were noted at the step involving protonation of the oxazolidine ring oxygen. Calculations predict this step to be the most endothermic one at basic pH, and therefore probably it is rate-determining. This step is considerably more endothermic for the trans-oxazolidine than for the cis-isomer. The results of calculations show the O-protonated intermediate formed from the cis-isomer differs in both energy and geometry from the corresponding intermediate obtained from the trans-isomer. Upon O-protonation, the trans-isomer forms a stable O-protonated oxazolidine. However, the cis-isomer undergoes immediate ring-opening to form a syn-cationic imine. The intermediate obtained from the trans-isomer is also higher in energy than the intermediate obtained from the cis-isomer. These results suggest that the relative ease of ring-opening of the cis-isomer compared to that of the trans-isomer explains why the cis-isomer hydrolyzes much faster than the trans-isomer in basic solution.
Transport critical currents and grain boundary peak links in bulk YBa2Cu3Ox

Abstract We summarize our previous studies on transport critical current density and present transport and electron microscopy data that provide significant physical insights into grain boundary weak-links and transport properties. By changing the sintering parameters and liquid processing methods, the transport Jc in the plateau regime is considerably increased. We conclude that transport Jc characteristics under a magnetic field are determined mainly by the portions of strongly coupled regions at grain boundaries. Thus, the transport Jc may not necessarily be connected with the gross orientation of the grain boundaries. The magnitude of the transport Jc under a magnetic field is proportional to the total area of the strongly coupled regions at the grain boundaries.
Superexponential long-term trends in information technology

Abstract Moore's Law has created a popular perception of exponential progress in information technology. But is the progress of IT really exponential? In this paper we examine long time series of data documenting progress in information technology gathered by [1]. We analyze six different historical trends of progress for several technologies grouped into the following three functional tasks: information storage, information transportation (bandwidth), and information transformation (speed of computation). Five of the six datasets extend back to the nineteenth century. We perform statistical analyses and show that in all six cases one can reject the exponential hypothesis at statistically significant levels. In contrast, one cannot reject the hypothesis of superexponential growth with decreasing doubling times. This raises questions about whether past trends in the improvement of information technology are sustainable.