cssi/SciSciGPT-SciSciNet huggingface dataset:
Role of wind in regulating phytoplankton blooms on the Mid-Atlantic Bight

Abstract Mixing has long been recognized as having an important role in influencing underwater light and nutrient budgets and thus regulating phytoplankton bloom. Mixing related to stratification and de-stratification is a key parameter of the physical environment that can control the timing and magnitude of blooms. Here we use a high-resolution three-dimensional biogeochemical model in the Mid-Atlantic Bight (MAB) to study phytoplankton bloom dynamics for the years 2004–2007. We present a simulated fall-winter bloom in the shelf region and spring bloom in the shelf-break front region. The ratio of light over mixed layer depth (MLD) was used to determine the trade-off effects of mixing (increase mixing will increase nutrients availability but decrease light availability). We find that the critical light value (I′chl mas) is around 60 (W m−2) for the shelf region and 150 (W m−2) for the shelf-break front region. There is a predictable linear regression relationship between I′chl mas and depth. A sensitivity run with no wind forcing was used to test the role of wind-induced mixing on the balance between light and nutrient terms and its influence on timing and magnitude of the bloom. The phytoplankton dynamics in the shelf-break front region are found to be more sensitive to the wind-induced mixing.
Risk of obstructive sleep apnea in obese and nonobese women with polycystic ovary syndrome and healthy reproductively normal women

Objective To study the risk for obstructive sleep apnea (OSA) in a group of nonobese and obese polycystic ovary syndrome (PCOS) and control women. Design Prospective study. Setting Academic tertiary care medical center. Patient(s) Forty-four women with PCOS and 34 control women. Intervention(s) All of the women completed the Berlin questionnaire for assessment of OSA risk. Main Outcome Measure(s) All of the women underwent fasting determination of androgens, glucose, and insulin. Result(s) Women with PCOS were more obese compared with control women. However, there were no differences in BMI once subjects were divided into nonobese (PCOS: n=17; control: n=26) and obese (PCOS: n=27; control: n=8) groups. Women with PCOS had higher prevalence of high-risk OSA compared with control women (47% vs. 15%). However, none of the nonobese PCOS and control women screened positively for high-risk OSA. Among the obese group, the risk did not differ between groups (77% vs. 63%). Conclusion(s) Our findings indicate that even though the risk for OSA in PCOS is high, it is related to the high prevalence of severe obesity. The risk for OSA among nonobese women with PCOS is very low. However, our findings are limited by lack of polysomnographic confirmation of OSA.
Changes and variability in concentration of heavy metals in sewage sludge during composting

Abstract The heavy metal concentration of sewage sludge increased during composting for cadmium, chromium, lead and zinc and decreased for copper and nickel. Cadmium and lead were the most variable of the metals, copper and zinc the least. Variability within a batch was small (variation of 4–12%). Variability attributable to batch‐to‐batch differences was generally larger (variation of 4–37%). The variability of sludge entering the batch process and of compost exiting the process were similar for each metal.
Crustal structure and tectonic evolution of the anza rift, northern Kenya

Abstract The Anza trough is a Mesozoic rift located in northern Kenya that appears to be the failed third arm of a paleo-triple junction which allowed the separation of Madagascar from Africa during the Jurassic. The rift is oriented NW-SE and its tectonic evolution is related to that of the Mesozoic southern Sudan rift system. We analyzed seismic and gravity data from the southwestern side of the Anza rift including the Chalbi Desert to gain a better understanding of rift structure. Gravity data delineate the main rift basins as well as a small sub-basin on the southwest side of the main rift. Normal faulting evident on the NW end of a 42-km-long, NW-SE oriented Vibroseis® profile, marks the western boundary of the sub-basin. This sub-basin is offset from the trend of the main Anza trough; the western boundary may be a complex fault zone accommodating a change in direction of the main rift trend. Gravity values increase to the NW in the faulted area, suggesting shallowing of basement. A strong NW-dipping reflection from 0.5 s to almost 3 s is interpreted as a pre- to mid-Cretaceous unconformity. The configuration of the unconformity and the normal faulting strongly resembles the half-graben geometry imaged in the East African Rift. Numerous discontinuous reflections can be seen deeper in the section between 6 and 9 s, but a distinct reflection Moho cannot be interpreted with certainty. In addition to seismic and gravity data, regional geologic and well data lead us to conclude that there are probably Jurassic marine sediments in the bottom of the Anza rift.
A new Malthusianism

Malthusianism is one of the most pervasive, if not the dominant, response to the current global political and economic crisis. It derives its name from the doctrine articulated by English clergyman‐turned‐economist Thomas Malthus, in 1798. Malthusianism views the numerical increase of the human population as the root cause of natural resource depletion, poverty, and social unrest, and population control as the primary solution to these problems.
Physio-chemical degradation of thermally aged hypalon glove samples

Abstract Attenuated total reflection (ATR) infrared spectra have been analyzed using multivariate curve resolution (MCR) to capture the chemistry of the thermal degradation in the aging of chlorosulfonated polyethylene (Hypalon ® ) glove samples. The analysis demonstrates the primary degradation pathways to be oxidation (formation of ketones and carboxylic acids), dehydrochlorination with formation of –CC– groups, and polymer crosslinking with changes in the C–H functional groups. From the multivariate analysis, the dominant degradation pathway involves carbon–carbon double bond formation and oxidation to form ketones. The tensile properties (modulus and elongation at break) demonstrate stiffening of the material with aging time. The dynamic mechanical data show that the storage modulus and mechanical loss tangent are also strongly affected with aging due to a hardening of the material. Taken together the mechanical and ATR data indicate that in thermal aging hypalon degrades by dehydrochlorination and loss of –SO 2 Cl functionality with –CC– formation, oxidation, and crosslinking causing the material to harden and become brittle.
A neural dynamics model for structural optimization—Theory

Abstract A neural dynamics model is presented for optimal design of structures. The Lyapunov function is used to develop the neural dynamics structural optimization model and prove its stability. An exterior penalty function method is adopted to formulate an objective function for the general constrained structural optimization problem in the form of the Lyapunov function. A learning rule is developed by integrating the Kuhn-Tucker necessary condition for a local minimum with the formulated Lyapunov function. The topology of the neural dynamics model consists of two distinct layers: variable layer and constraint layer. The numbers of nodes in the variable and constraint layers correspond to the numbers of design variables and constraints in the structural optimization problem. Both excitatory and inhibitory connection types are used for adjusting the states of the nodes. In addition to commonly-used inter-layer connections, recurrent connections are used to represent the gradient information of the objective function. In a companion paper the neural dynamics model is applied to optimum plastic design of steel structures.
Calibrations, torsion classes, and wrapped M-branes

The present work has two goals. The first is to complete the classification of geometries in terms of torsion classes of M-branes wrapping cycles of a Calabi-Yau manifold. The second goal is to give insight into the physical meaning of the torsion class constraints. We accomplish both tasks by defining new energy minimizing calibrations in M-brane backgrounds. When fluxes are turned on, it is these calibrations that are relevant, rather than those which had previously been defined in the context of purely geometric backgrounds.
Time and frequency resolution of CS2 fluorescence excited by a nitrogen laser

Abstract The fluorescence of CS 2 vapor, excited by a nitrogen laser, is dispersed. It reveals several identifiable ν″ 2 progressions in the near ultraviolet and irregular bands overlying an apparent continuum in the visible. Temperature studies indicate that the spectrum is temperature sensitive and that the banded structure is principally due to excitation from ν″ 2 = 1 while the continuum is from ν″ 2 = 2. Time resolved studies confirm a two exponential decay and assign the shorter (2.9 μs) lifetime to the bands and the longer (17 μs) one to the continuum. It is suggested that the laser populates two vibronic levels of the T 1 A 2 state and that these two levels have different radiative properties. Reasons for this difference and the nature of the continuum are discussed.
Enhancing the value of journal club: use of a structured review instrument.

A study was undertaken to determine if use of a structured review instrument (SRI) increased the perceived overall satisfaction with a journal club in a group of emergency medicine residents. Before and 6 months after the introduction of a structured checklist format for article review, a 5-point Likert scale (1 = worst, 5 = best) was used to assess residents' satisfaction with the journal club, as well as the following subsidiary outcome parameters resident and leader workload, educational value in interpreting the medical literature, and application of the information to clinical practice. Additional measured outcome variables included resident attendance and number of articles read per attendee. Continuous and categorical data were compared using the Wilcoxon Rank Sum test and Fisher's exact test, respectively. Following introduction of the SRI, residents were more satisfied with the journal club (3.8 v 3.2, P < .05). There was no change in resident attendance (92% v 71%, P = .65), total articles read (75% v 70%, P = .33), or perceived workload (3.3 v 3.1; P = .3). The use of a SRI was found to increase resident satisfaction and improve the perceived educational value of a journal club without increasing residents' workload or decreasing attendance.
Improved phase stability and electrochemical performance of (Y,In,Ca)BaCo3ZnO7+δ cathodes for intermediate temperature solid oxide fuel cells

Abstract With an aim to combine the performance-enhancing properties of Ca with the stability-promoting properties of In in the s wedenborgite YBaCo 4 O 7+ δ -based cathodes for solid oxide fuel cells (SOFC), cation-substituted Y 1− x − y In x Ca y BaCo 3 ZnO 7+ δ (0.2 ≤ ( x + y ) ≤ 0.5) oxides have been explored. All samples presented in this work are stable in air after 120 h exposure to 600, 700, and 800 °C. Increasing In content shows a negligible impact on polarization resistances ( R p ), but causes an increase in the activation energies ( E a ) of (Y,In,Ca)BaCo 3 ZnO 7+ δ + Gd 0.2 Ce 0.8 O 1.9 (GDC) composite cathodes on 8 mol% yttria-stabilized zirconia (8YSZ) electrolyte supported symmetric cells. Increasing Ca content shows a decrease in R p and an increase in E a on similar electrochemical cells. All (Y,In,Ca)BaCo 3 ZnO 7+ δ samples investigated here show superior performance compared to the unsubstituted YBaCo 3 ZnO 7+ δ + GDC cathode in the range of 400–800 °C. Especially, the Y 0.5 In 0.1 Ca 0.4 BaCo 3 ZnO 7+ δ + GDC composite cathode exhibits good performance on GDC electrolytes in the range of 400–600 °C. With superior phase stability and electrochemical performance, the (Y,In,Ca)BaCo 3 ZnO 7+ δ series of oxides are attractive cathode candidates for intermediate temperature SOFCs.
Chromatography of ionizable positional isomers with methanol–water–carbon dioxide mixtures

Abstract The separations of five groups of ionogenic disubstituted benzene isomers were achieved by taking advantage of the pH variation caused by proportions of CO 2 in the methanol–water–CO 2 mobile phases without the addition of an aqueous buffer. The retention behavior of acidic, basic, and zwitterionic isomers was predominantly affected by the dissociation of these analytes within methanol–water–CO 2 mobile phases of different pH. A comparison with previously published reversed-phase high-performance liquid chromatography (HPLC) of these isomers revealed that resolution improvement for anisic acid, toluic acid and aminobenzoic acid isomers was achieved with methanol–water–CO 2 enhanced-fluidity liquids. Significant reductions in the retention factors were also obtained. Meanwhile, the detrimental effect of the presence of an aqueous buffer on the stationary phase was avoided which made fast repetitive analyses possible.
Comparative study of the aromatic profiles of two different plum species: Prunus salicina Lindl and Prunus simonii L

Volatile compounds of two plum species (Prunus salicina Lindl and Prunus simonii L) were analyzed by capillary gas chromatography-mass spectrometry using simultaneous vacuum distillation extraction. Aroma patterns were identified and quantified. A total of 60 compounds were identified, of which 23 were unique to P simonii. The profile of P simonii, as well as a study of the odor unit values of some identified compounds, indicated a much stronger aroma than P salicina. Hexyl acetate, which produces a characteristic apple aroma, was present in P simonii at levels 50-fold higher than in the studied cultivars of P salicina.
Trp64Arg substitution in the β3-adrenergic receptor does not relate to body weight in healthy, premenopausal women

Trp64Arg substitution in the β 3 -adrenergic receptor does not relate to body weight in healthy, premenopausal women
SOME JUSTIFICATIONS FOR PARSIMONY IN PSYCHOLOGY

Summary.-Batrig's suggestion that psychologists should ignore considerations of simplicity in research strategy and theory construction was disputed in the present paper. Kerneny's analysis of the crucial role of simplicity in selecting an hypothesis to describe a functional relationship was cited. In addition, the view of Popper and others that the simplicity of a theory is closely related to its falsifiability was presented. It was asserted that a simplicity criterion is an essential element of any scientific endeavor and thus should be adhered to more closely by psychologists. Battig (1962) has argued that criteria of simplicity have been applied inappropriately by psychologists when evaluating theories and research practices and that, when meaningfully applied, the simplicity criterion has been unnecessary. The point of view is offered in the present paper that the principle of simplicity is essen:ial to any scientific enterprise, thac it is fundamentally related to most basic and well-accepted rules of science, and that failure to observe it, as Battig (19617) has suggested, would severely hamper the progress of psychology. In this connection, no attempt will be made to justify simplicity on the basis of aesthetic considerations or on the basis of metaphysical arguments. Any claim that the laws describing nature (including those describing behavior) ought to be simple because nature is simple can be seen to be circular. If two or more hypothetical laws are equally in accord with the data at hand, the principle of parsimony dictates that the simplest one be adopted. But this decision cannot rest on an empirical basis if each law is equally in accord with the available information. By rhe same token, any decision not to adopt rhe simplest law is also not justifiable on empirical or metaphysical grounds. Yet much of Battig's argument rests on his assertion thac "psychologists are presently working at a far too simple level, well below the actual level of complexity of our behavioral phenonena" (1962, p. 571). Although he concedes that this view may be erroneous, Battig claims that, "as long as parsimony is to be the guide in choice of research strategy, we are unnecessarily handicapping ourselves in finding out whether it is [erroneous] or not" (1962, p. 571). Arguments will be presented hore to show thac, on the contrary, failure to observe the principle of simplicity would make it exceedingly difficult to answer any questions about nature scicntifically. To begin with an example which has received previous attention (Kemeny, 1953), consider the problem of selecting an hypothesis to describe the functional relationship between two variables. Suppose n measurements of variable
Moreno, Luis (ed.). "Reformas de las Políticas de Bienestar en España"

Normal 0 21 MicrosoftInternetExplorer4 Resena Autor del libro: Luis Moreno (ed.) Titulo: Reformas de las Politicas de Bienestar en Espana Lugar de publicacion: Madrid Editorial: Siglo XXI Ano de publicacion: 2009 Numero de paginas: 385
Na+ and K+ uptake and exchange by the amphibian oocyte during the first meiotic division

Abstract The uptake and efflux of 22Na and 42K were studied in denuded Rana pipiens oocytes following progesterone induction of the resumption of meiotic maturation. Coincident with the breakdown of the large nucleus, or germinal vesicle, there is a virtual disappearance of K+ permeability of the oocyte plasma membrane. Only about 1–2% of the total [K+]i is exchanged by completion of nuclear breakdown (8–10 hr) and accounts for the finding that there is no detectable change in total [K+]i during the first meiotic division (20–24 hr). In the case of Na+, influx, exchange, and efflux kinetics were unchanged during the first meiotic division, with 20 and 35% of the total oocyte Na+ exchanging by the completion of nuclear breakdown and first meiotic division, respectively. Removal of Na+ from the incubation medium produced and earlier nuclear breakdown, whereas a K-free medium delayed breakdown. There was no effect of 10 μm/ml tetrodotoxin or 10−5 M strophanthidin on the time course of nuclear breakdown. Thus one action of progesterone appears to be a selective turning off of “K channels” in the oocyte plasma membrane. The disappearance of K selectivity of the oocyte plasma membrane coincides with plasma membrane depolarization, as well as nuclear swelling and breakdown.
The Prevalence of Disabilities and Maltreatment among Runaway Children.

Abstract Objective. This research was conducted to determine the prevalence of disabilities among abused and nonabused runaways within a hospital population (Study 1) and community school population (Study 2) and to identify any associations between disability, maltreatment, family stress factors, academic achievement, school attendance, domestic violence and runaway status. Method: Descriptive information was collected for maltreated and nonmaltreated runaways from hospital ( N = 39,352; 255 runaways) and school ( N = 40,211; 562 runaways) populations including: disability status, type of maltreatment, family stress factors, record of domestic violence in the family, academic achievement and attendance. Results: The prevalence rate of disabilities among the maltreated runaways was 83.1% and 47% among the nonmaltreated runaways in the hospital sample and 34% and 17%, respectively, in the school sample. Children and youth with disabilities were at increased risk to become runaways in both populations. The presence of maltreatment significantly increased the association between running away and disability status. Children with behavior disorders, mental retardation, and some type of communication disorder were significantly more likely to run away than children with other disabilities. Among the maltreated runaways with and without disabilities, physical abuse and sexual abuse were significantly associated with running away. Records of domestic violence were more prevalent in the families of runaways with behavior disorders and no diagnosed disability. Lower academic achievement, poor school attendance, and more family stress factors were associated with maltreatment, disability and runaway status. Conclusions: Children and youth with disabilities are unidentified and unrecognized among runaways. Professionals working with runaways and their families need to be cognizant of the special needs of the population, particularly with respect to behavior disorders, communication disabilities, and mental retardation and reconsider current policy to routinely reunite runaways with their families when running away was precipitated by traumatagenic factors within the family.
Research mentor: a tool to aid in the training of scientific investigators

We describe an intelligent mentor for teaching the ability to think scientifically. The student is given an arbitrary starting place in the matrix of knowledge surrounding an area of biomedical research. He/she then proposes hypotheses and supporting experiments which are checked against the knowledge base for agreement, consistency or contradiction. Agreement or consistency results in the report of successful experiments, thus advancing the student's “state-of-the-art.” Contradiction results in failure of the experiment to support the hypothesis. In either case, a new hypothesis can then be proposed and tested, each step being potentially contingent on results of the last. The knowledge base upon which the system operates is a frame-based implementation of the Biomatrix, augmented with pointers to literature citations. Each object (hypotheses, experiments, cells, animals, etc.) is described in terms of its properties and its relations to other objects. Thus, the matrix is represented as a semantic network. Other objects create the relations among the hypotheses, subhypotheses, experiments and other parts of the knowledge base. This system provides experiential learning at a rate determined by the student, while saving costly resources.
A sequential Bayesian inference framework for blind frequency offset estimation

Precise estimation of synchronization parameters is essential for reliable data detection in digital communications and phase errors can result in significant performance degradation. The literature on estimation of synchronization parameters, including the carrier frequency offset, are based on approximations or heuristics because the optimal estimation problem is analytically intractable for most cases of interest. We develop an online Bayesian inference procedure for blind estimation of the frequency offset, for arbitrary signal constellations. Our unified approach is built on a sequential inference procedure that leverages a novel result on conjugacy of the von Mises and Gaussian distributions. This conjugacy allows for an easily computable, closed form parametric expression for the posterior distribution of the parameters given the streaming data, in which hyperparameters are recursively updated, making the optimal sequential estimation problem mathematically tractable. Our algorithm is computationally efficient and can be implemented in real-time with very low memory requirements. Numerical experiments are also provided and show that our methods outperform approximate sequential maximum-likelihood carrier frequency offset estimators.
The growth of curvature near a space-time singularity

The causal structure of space-time constrains the rate of growth of Ricci curvature near a singularity. Roughly speaking, Ro0 cannot grow faster than 1/t 2 near a singularity in any physically realistic space-time, and Roo must grow at least as fast as 1/t near a curvature singularity in a conformally flat spacetime. The following theorems make this statement precise. Theorem 1. Let 7(t) be a null geodesic generator of the boundary of a TIF. Then there is no affine parameter interval (s l , s2) of 7(s) satisfying
The Extent of the Phenomenon of Oscillatory Anion Incorporation in Alumina Barrier Films

On montre que l'insertion oscillatoire de tungstate et d'autres anions, tels que MoO 4 2− , MnO 4 − et CrO 4 − dans des films anodiques d'alumine, confirme la nature generale du phenomene des oscillations electrochimiques produites a l'etat solide
Effect of dietary restriction on glutathione S-transferase activity specific toward aflatoxin B1-8,9-epoxide

Dietary restriction (DR) reduced the metabolic activation of aflatoxin B1 (AFB1) in rats. This reduction may be attributed to the decrease of cytochrome P-450-mediated AFB1 epoxidation and/or increase in the detoxification of AFB1 catalyzed by hepatic glutathione S-transferase (GST) and other phase II detoxification enzymes. In this study the effect of DR on male rat liver cytosolic GST activity toward AFB1-8,9-epoxide was studied. The chemically-synthesized AFB1-8,9-epoxide was used as the substrate in this assay, and the formation of AFB1-GSH conjugate was analyzed by HPLC. Male Fischer 344 rats fed DR diets (60% of the food consumption of ad libitum (AL)-fed rats) showed a 2.4-fold increase in GST activity when AFB1-epoxide was used as the substrate. The results from the enzyme kinetic study showed that DR increased Vmax of the liver cytosolic GST but not the Km. Acute DR has little or no impact on GST activity when 1-chloro-2,4-dinitrobenzene and 2,4-dichloronitrobenzene were used as substrates. The mouse liver GST activity toward AFB1-epoxide was 3-fold greater than that of phenobarbital-induced rats, 4.5-fold greater than DR rats, and 14.7-fold greater than the GST activity of AL rats. This direct assay of liver GST activity using AFB1-epoxide as the substrate is useful for studying AFB1-induced biomarkers, such as AFB1-GSH conjugation and AFB1-DNA adducts.
Thermodynamics of the solvent swelling of coal

Sorption of pyridine by the pyridine-extracts of three premium Argonne coals was studied at several relative vapor pressures at 50{degree}C. The amount of pyridine sorbed by each extract increases linearly with pyridine vapor pressure. The extrapolated lines do not pass through the origin. At low pressures, a dual-mode sorption mechanism is proposed, whereby pyridine concurrently fills holes (microvoids) and dissolves into the extract. At higher pressures, we propose that the holes are saturated and that only dissolution is occurring. Dissolution thus increases linearly with pressure of pyridine. Not all pyridine can be desorbed from the extract. The amount remaining corresponds closely to the intercept of the straight-line curve. This result suggests that pyridine cannot be desorbed from the holes at the experimental temperature. 1 ref., 4 figs., 1 tab.
PROTEIN CONTENTS OF SEED YIELDS OF FIELD‐GROWN SOYBEANS EXPOSED TO simulated ACIDIC RAIN: ASSESSMENT OF THE SENSITIVITIES OF FOUR CULTIVARS AND EFFECTS OF DURATION OF SIMULATED RAINFALL

Summary Analyses of seeds harvested from field-grown soybeans (Glycine max Merrill) demonstrated that simulated acidic rainfalls can significantly decrease total protein contents. In an experiment conducted in 1983, seed yields of plants exposed twice weekly to long duration rainfalls showed no significant differences in seed protein contents among the acidity levels tested. In contrast, significant differences in protein contents were found for seed samples from the short duration, daily rainfalls. Seeds of plants exposed to simulated rain of pH 5.6 had average protein contents of 37.9% compared with a range between 30.6 and 32.1 % from plants exposed to lower pH values. Overall the protein contents of seeds of acidic rainfall treatments, expressed on a per plant basis, ranged from 23 to 34%. The results suggest that the response of soybean seed yields to acidity are affected by duration and frequency of simulated rainfalls. In the 1984 growing season, four commercial cultivars were tested under conditions of longer duration rainfalls, applied twice weekly. Significant treatment effects occurred only to the Amsoy cultivar and not to Asgrow, Corsoy or Hobbit. For the latter three cultivars the protein contents of samples were all relatively high (means were all between 35 and 39%). The relatively low protein content of Amsoy soybeans exposed to simulated rainfalls of pH 2.7 was apparently responsible for the statistical significance among treatments. These and previous results demonstrate that rainfall acidity can significantly affect protein contents of seeds of field-grown soybeans and that effects on protein content are independent of changes in plant seed yields.
Elwood Murray: Innovator, integrator, educator

A case study of Professor Elwood Murray was undertaken to reveal his impact both on his students and on the curriculum at the University of Denver. Interviews were conducted with Dr. Murray as well as with many of his former students and colleagues. Questionnaires were distributed and results compiled, catalogs from the Denver library were reviewed, and Murray's personal files were examined. Dr. Murray is seen to be an innovator who pioneered in the application of social science techniques to the speech classroom, and a man of vision who left a lasting impression on his students.
A significant part of macrophage-derived growth factor consists of at least two forms of PDGF

The macrophage has been suggested to be responsible for the connective tissue cell proliferation that accompanies most chronic inflammatory responses. One of the secretory products of activated macrophages is MDGF, a growth factor (or factors) for fibroblasts, 3T3 cells, smooth muscle, and vascular endothelium. This report demonstrates that a significant portion of the mitogenic activity for 3T3 cells secreted by cultured human alveolar and peritoneal macrophages is due to a molecule (or molecules) similar to platelet-derived growth factor (PDGF). Two size classes (approximately 37,000-39,000 and 12,000-17,000 daltons) of mitogenically active PDGF-like molecules are detected by two criteria--antigenic similarity with PDGF and ability to compete with 125I-PDGF for high-affinity binding to the PDGF receptor. The presence of mRNA for the B chain of PDGF is demonstrated by Northern analysis, and de novo synthesis of these molecules by activated macrophages is shown by immunoprecipitation of 35S-labeled proteins with anti-PDGF IgG.
Structural changes in myosin subfragment 1 by mild denaturation and proteolysis probed by antibodies

The perturbations in the structure of myosin subfragment 1 (S1) by mild denaturation or proteolysis were investigated by measuring the inhibition of the binding of antibodies to immobilized S1 by treated S1 in a solution-phase competitive immunochemical assay. The structural changes in S1 were probed by using anti-50-kDa segment, anti-N-terminus, anti-27-kDa segment, and anti-A1 light chain monoclonal antibodies (MAbs). Methanol and heat denaturation increased MAb binding to the 50-kDa segment. MAb binding to regions in the 27-kDa segment was also promoted, slightly by methanol and more drastically by heat. Proteolysis also induced structural alterations in 50- and 27-kDa segments as shown by increased MAb binding to these regions in cleaved S1. These results indicate that mild denaturation and proteolysis induce structural perturbations which alter the epitope accessibility in 50- and 27-kDa segments of S1 and that antibody binding studies afford a sensitive probe to such perturbations.
The Relation of Viral Replication to Interstitial Pneumonitis in Murine Cytomegalovirus Lung Infection

Using a murine model of murine cytomegalovirus (MCMV) interstitial pneumonitis, we examined the relation between the virus content of the lung and lung disease. While MCMV alone does not cause lung disease, interstitial pneumonitis was present in all mice receiving both MCMV and a single dose of cyclophosphamide. In this case the severity of disease, judged by increases in wet weight of the lung, was proportional to the virus content of the lung. Although both acyclovir (50 mg/kg per day) and passive antibody administration reduced the MCMV titers in lung tissues by greater than 90%, histological evidence of interstitial pneumonitis was present in all animals. However, both virus inhibitors reduced the severity of interstitial pneumonitis in treated mice. While transient alterations in host immunity are necessary to induce interstitial pneumonitis after MCMV infection, the severity of interstitial pneumonitis seems to reflect the burden of virus replication. Reduction of virus growth does not prevent, but may moderate, MCMV interstitial pneumonitis.
EducationTeaching computing to everyone

Studying the lessons learned from creating high-demand computer science courses for non-computing majors.
Secondary Ion Mass Spectrometry Imaging of Molecular Distributions in Cultured Neurons and their Processes: Comparative Analysis of Sample Preparation

Neurons often exhibit a complex chemical distribution and topography; therefore, sample preparation protocols that preserve structures ranging from relatively large cell somata to small neurites and growth cones are important factors in secondary ion mass spectrometry (SIMS) imaging studies. Here, SIMS was used to investigate the subcellular localization of lipids and lipophilic species in neurons from Aplysia californica. Using individual neurons cultured on silicon wafers, we compared and optimized several SIMS sampling approaches. After an initial step to remove the high salt culturing media, formaldehyde, paraformaldehyde, and glycerol, and various combinations thereof, were tested for their ability to achieve cell stabilization during and after the removal of extracellular media. These treatments improved the preservation of cellular morphology as visualized with SIMS imaging. For analytes >250 Da, coating the cell surface with a 3.2 nm-thick gold layer increased the ion intensity; multiple analytes previously not observed or observed at low abundance were detected, including intact cholesterol and vitamin E molecular ions. However, once a sample was coated, many of the lower molecular mass (<200 Da) analyte signals were suppressed. The optimum approach depended on the analyte being studied; the approaches evaluated included rinsing with water and cell stabilization with glycerol and 4 % paraformaldehyde. The sample preparation methods described here enhance SIMS imaging of processes of individual cultured neurons over a broad mass range with enhanced image contrast.
Prediction intervals for future failures in the exponential distribution under hybrid censoring

A life test having the one-parameter exponential distribution is considered. Available data are from hybrid censored sampling. Methods are derived for predicting future failures, given a record of observed failures. Prediction intervals for future failures are also discussed. >
Experience with gabapentin for neuropathic pain in adolescents: report of five cases.

Summary Gabapentin is an antiepileptic drug indicated for the treatment of partial seizures in children. Many studies have proved its analgesic action in the treatment of neuropathic pain in adults and we have noticed an analgesic action of gabapentin in neuropathic pain in children. Five patients treated in the Children's Hospital Pain Control Service for intractable neuropathic pain were included in gabapentin treatment. Four were cancer patients and one suffered from neuropathic pain in the neck (C3). The visual analog scale (VAS) scores of pain were compared before and during treatment with gabapentin. We noticed a rapid improvement, in 1 week, of our patients’ VAS scores (from 9 or 10 to 4 or 3) with minimal adverse effects. In the follow-up period of 6 months we gradually reduced the dose of gabapentin. Our findings are that gabapentin should be included earlier in the treatment of neuropathic pain in adolescents, because it rapidly improves analgesia and has minimal side effects.
Underutilization of Mental Health Services Among Bereaved Caregivers With Prolonged Grief Disorder

Objective:This study examined grief and mental health service use among 86 bereaved caregivers of advanced cancer patients. Methods:Caregivers were assessed before (median=3.1 months) and after (median=6.6 months) patients' deaths for prolonged grief disorder, axis I psychiatric disorders, mental health service use, suicidality, and health-related quality of life. Results:Sixteen percent of the bereaved sample met criteria for prolonged grief disorder, which was significantly associated with suicidality and poorer health-related quality of life, but not with mental health service use. The majority of bereaved caregivers with prolonged grief disorder did not access mental health services. In multivariable analyses, having discussed psychological concerns with a health care professional when the patient was ill was the only significant predictor of mental health service use during bereavement. Conclusions:Because bereaved caregivers with prolonged grief disorder underutilize mental health services, connecti...
Delivering quantum dot-peptide bioconjugates to the cellular cytosol: escaping from the endolysosomal system.

For luminescent quantum dots (QDs) to realize their full potential as intracellular labeling, imaging and sensing reagents, robust noninvasive methods for their delivery to the cellular cytosol must be developed. Our aim in this study was to explore a range of methods aimed at delivering QDs to the cytosol. We have previously shown that QDs functionalized with a polyarginine ‘Tat’ cell-penetrating peptide (CPP) could be specifically delivered to cells via endocytic uptake with no adverse effects on cellular proliferation. We began by assessing the long-term intracellular fate and stability of these QD-peptide conjugates. We found that the QDs remained sequestered within acidic endolysosomal vesicles for at least three days after initial uptake while the CPP appeared to remain stably associated with the QD throughout this time. We next explored techniques designed to either actively deliver QDs directly to the cytosol or to combine endocytosis with subsequent endosomal escape to the cytosol in several eukaryotic cell lines. Active delivery methods such as electroporation and nucleofection delivered only modest amounts of QDs to the cytosol as aggregates. Delivery of QDs using a variety of transfection polymers also resulted in primarily endosomal sequestration of QDs. However, in one case the commercial PULSin™ reagent did facilitate a modest cytosolic dispersal of QDs, but only after several days in culture and with significant polymer-induced cytotoxicity. Finally, we demonstrated that an amphiphilic peptide designed to mediate cell penetration and vesicle membrane interactions could mediate rapid QD uptake by endocytosis followed by a slower efficient endosomal release which peaked at 48 h after initial delivery. Importantly, this QD-peptide bioconjugate elicited minimal cytotoxicity in the cell lines tested.
Discovering functional linkages and uncharacterized cellular pathways using phylogenetic profile comparisons: a comprehensive assessment

A widely-used approach for discovering functional and physical interactions among proteins involves phylogenetic profile comparisons (PPCs). Here, proteins with similar profiles are inferred to be functionally related under the assumption that proteins involved in the same metabolic pathway or cellular system are likely to have been co-inherited during evolution. Our experimentation with E. coli and yeast proteins with 16 different carefully composed reference sets of genomes revealed that the phyletic patterns of proteins in prokaryotes alone could be adequate enough to make reasonably accurate functional linkage predictions. A slight improvement in performance is observed on adding few eukaryotes into the reference set, but a noticeable drop-off in performance is observed with increased number of eukaryotes. Inclusion of most parasitic, pathogenic or vertebrate genomes and multiple strains of the same species into the reference set do not necessarily contribute to an improved sensitivity or accuracy. Interestingly, we also found that evolutionary histories of individual pathways have a significant affect on the performance of the PPC approach with respect to a particular reference set. For example, to accurately predict functional links in carbohydrate or lipid metabolism, a reference set solely composed of prokaryotic (or bacterial) genomes performed among the best compared to one composed of genomes from all three super-kingdoms; this is in contrast to predicting functional links in translation for which a reference set composed of prokaryotic (or bacterial) genomes performed the worst. We also demonstrate that the widely used random null model to quantify the statistical significance of profile similarity is incomplete, which could result in an increased number of false-positives. Contrary to previous proposals, it is not merely the number of genomes but a careful selection of informative genomes in the reference set that influences the prediction accuracy of the PPC approach. We note that the predictive power of the PPC approach, especially in eukaryotes, is heavily influenced by the primary endosymbiosis and subsequent bacterial contributions. The over-representation of parasitic unicellular eukaryotes and vertebrates additionally make eukaryotes less useful in the reference sets. Reference sets composed of highly non-redundant set of genomes from all three super-kingdoms fare better with pathways showing considerable vertical inheritance and strong conservation (e.g. translation apparatus), while reference sets solely composed of prokaryotic genomes fare better for more variable pathways like carbohydrate metabolism. Differential performance of the PPC approach on various pathways, and a weak positive correlation between functional and profile similarities suggest that caution should be exercised while interpreting functional linkages inferred from genome-wide large-scale profile comparisons using a single reference set.
Kinetics of the reactions of singlet molecular oxygen (O21Δg) with organic compounds in the gas phase

The reactions of singlet molecular oxygen (O21Δg) with a series of organic compounds have been studied in the gas phase at 298°K. The concentration of singlet molecular oxygen was determined by titration with 2,5-dimethylfuran. The titration technique was checked using a photoionization technique. Absolute rate constants were measured on the basis of the loss of organic reactant and, in some cases, of singlet molecular oxygen. It was found that the usual method of producing singlet molecular oxygen in the gas phase can also, under some conditions, allow reactive species other than singlet molecular oxygen to enter the reactor, leading to serious errors in the determination of rate constants. This problem was eliminated by carrying out the rate measurements in the presence of a small amount of nitrogen dioxide a radical scavenger.
ABCD: eliminating array bounds checks on demand

To guarantee typesafe execution, Java and other strongly typed languages require bounds checking of array accesses. Because array-bounds checks may raise exceptions, they block code motion of instructions with side effects, thus preventing many useful code optimizations, such as partial redundancy elimination or instruction scheduling of memory operations. Furthermore, because it is not expressible at bytecode level, the elimination of bounds checks can only be performed at run time, after the bytecode program is loaded. Using existing powerful bounds-check optimizers at run time is not feasible, however, because they are too heavyweight for the dynamic compilation setting.ABCD is a light-weight algorithm for elimination of Array Bounds Checks on Demand. Its design emphasizes simplicity and efficiency. In essence, ABCD works by adding a few edges to the SSA value graph and performing a simple traversal of the graph. Despite its simplicity, ABCD is surprisingly powerful. On our benchmarks, ABCD removes on average 45% of dynamic bound check instructions, sometimes achieving near-ideal optimization. The efficiency of ABCD stems from two factors. First, ABCD works on a sparse representation. As a result, it requires on average fewer than 10 simple analysis steps per bounds check. Second, ABCD is demand-driven. It can be applied to a set of frequently executed (hot) bounds checks, which makes it suitable for the dynamic-compilation setting, in which compile-time cost is constrained but hot statements are known.
Ion-beam assisted deposition of bi-axially aligned MgO template films for YBCO coated conductors

We report the results of experiments with ion-beam-assisted deposition (IBAD) of MgO using in-situ monitoring with Reflected High-Energy Electron Diffraction (RHEED). Strips of polished Haynes 242 and Inconel 625 nickel-based super-alloys have been used as substrates for these experiments. The in-plane texture of the MgO, as measured by X-ray /spl phi/ scan, resulted in FWHM values between 11 and 15/spl deg/. Using pulsed-laser deposition, the IBAD MgO template films were then overcoated with buffer layer films and a final superconducting film of YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta//. The best superconducting transport properties measured on these YBCO films were: an Ic (75 K, self-field, 1 cm wide) of 41.6 A, and a narrow-bridge J/sub c/ (1.35 /spl mu/m thick film) of 0.46 MA/cm/sup 2/.
An improved method for shock consolidation of powders

A technique for shock consolidation of powders was developed. This technique uses the cylindrical geometry with two co-axial tubes. The powder is contained in the internal tube. The external tube is surrounded by the explosive charge, which is detonated at one end; this external tube acts as a flyer tube, impacting the internal tube. This technique generates pressures in the powder that can be several times higher than the ones generated by the single-tube technique. The main advantage of this technique is that it allows the use of low detonation-velocity explosives for consolidating hard powders. The lower detonation-velocity explosives minimize cracking of compacts. Significant improvements in compact quality were obtained in nickel-base superalloys, titanium alloys and aluminum-lithium alloys. Ru ce tube exteme agit comme un tube volant tombant sur le tube inteme. Cette methode provoque dans la poudre des pressions plusieurs fois superieures a celles que tree la m&ode I tm seul tube: sone principal avantage est de permettre l'utilisation d'explosifs a faible viteese de detonation pour consolider des poudres dures. Les explosifs a vitesse de detonation plus basse diminuent la fissuration des poudres t-endues compactes. Nous avons obtenu des ameliorations importantes de la qualiti des poudres compacttes dans le cas de superalliages a base nickel, d'alliages de titane et d'alliages aluminium-lithium. mansung-Ein neues Verfahren zur Stogverdichtung von Pulvem wird vorgestellt. Hierbei wird eine xylindrische Geometrie mit zwei koachsialen Rohren verwendet. Das Pulver befindet sich im inneren Rohr. Das PuDere Rohr ist umgeben von einer. Explosivladung. Diese wird an einem Ende geziindet, wodurch das BuBere auf das innere Rohr geschossen wird. Mit diesem Verfahren kiinnen Drucke auf das Pulver ausgetlbt werden, die mehrfach hiiher sind als diejenigen, die bei dem Einrohrverfahren erreicht werden kbnnen. Ein wichtiger Vorteil des Zweirohrverfahrens ist, dag Explosivstoffe mit niedriger Detonationsgeschwindigkeit aur Verdichtung harter Pulver verwendet werden klinnen. Die geringere Detonationsgeschwindigkeit verringert Rigbildung im PreOling. Mit diesem Verfahren konnten deutliche Verbesserungen in der Qualitiit von Preglingen aus Superlegierungen auf Nickelbasis, aus Titan- und Aluminium-Lithium-Legierungen erreicht werden.