cssi/SciSciGPT-SciSciNet huggingface dataset:
Self-Imposed Delay of Gratification in Children: The Development of Self-Regulatory Behavior in Stressful Situations

Publisher Summary This chapter presents an overview of self-imposed delay of gratification in children. Self-imposed delay of gratification is at once a simple and multidetermined phenomenon behavior. The ability or willingness to postpone immediate rewards for the sake of greater delayed rewards is best understood as having two phases, which corresponds to a cognitive and a behavioral aspect. The cognitive component is most clearly shown in the statement of preference between immediate and delayed rewards. This statement is determined by a variety of considerations—both situational and personal. The second phase is patience or delay maintenance behavior. Once a decision to wait has been made, the individual is now faced with the prospect of following through on a course of action dictated by the delay choice. This phase of self-imposed delay of gratification is also influenced by a number of situational and personal factors. As in the case of delay decisions, these influential factors do not work independently but rather these factors interact. Thus, the prediction of a particular child's decision to delay or not and the prediction of whether that child will actually wait if the decision to delay is in fact made are most difficult predictions indeed.
24 Basophil Activation Test may facilitate ABPA diagnosis in CF patients

Objective Diagnosis of Allergic Bronchopulmonary Aspergillosis (ABPA) complicating cystic fibrosis (CF) remains problematic. As Basophil Activation Test (BAT) has been applied on the diagnosis of many Th2 mediated conditions, it could be a promising method for ABPA diagnosis. Methods We present 21 cases of patients with probable ABPA who did not fulfill the minimal diagnostic criteria. BAT was performed when patients' clinical and immunological status was deteriorated and they were followed up for 6 years. Results Fifteen patients (71.4%) were male and seven patients (33.3%) were homozygous for DF508 mutation. Twelve patients developed ABPA during the study period. In these patients the median CD63 was 71.89% while the median CD203 was 78.96%. The median time of diagnosis was ten months. In the group of nine patients who have not fulfilled the diagnostic criteria up to present, the median CD63 was 24.57% and the median CD203 was 60.74%. Differences were found statistically significant (p = 0.041 and p = 0.049 respectively). Conclusion BAT could be considered as an additional criterion for ABPA diagnosis, particularly in patients who do not fulfill the minimal diagnostic criteria.
Herpes Simplex Virus-Host Cell Relationships in Organized Cultures of Mammalian Nerve Tissues

Studies on the replication of herpes simplex virus in organized cultures of rat central nervous system (CNS) and peripheral nervous system (PNS) tissue demonstrated synthesis of intra- and extracellular virus, as determined by plaque assay on HEp-2 cells. Newly synthesized intracellular virus appeared 12 to 14 hr after inoculation of CNS, followed 10 hr later by the appearance of extracellular virus. In PNS cultures, where higher inputs of virus were introduced, intracellular virus appeared 6 to 8 hr after inoculation, followed by extracellular virus 12 hr later. Polykaryocyte formation was observed in CNS and PNS tissue involving neuroglial, meningeal, or Schwann cells. Neuron somas did not participate in polykaryocyte formation, but they underwent progressive morphological changes starting with increased cytoplasmic granularity followed by nucleolar distortions and disintegration, margination of nuclear chromatin, and the appearance of intranuclear inclusions. Finally, all recognizable cellular detail was lost. Immune serum globulin failed to inhibit both the progressive nature of the cytopathic effect and the synthesis of intracellular virus. These findings are discussed in relation to other in vitro systems, as well as to disease processes in man and animals.
Aces in the Deck: Four Principles for Assessing and Strengthning Student Poems

ABSTRACT An experiment in teaching and assessing the writing of poetry yields powerful insights and raises some engaging questions.
The determination of optimum operating conditions by the methods of dynamic programming

The mathematical technique known as dynamic programming is here introduced as a tool in the optimization of chemical reactors. The structure of the optimal problem is first analysed and two of the simpler problems (optimal conditions for a single reaction in a sequence of stirred tanks and a tubular reactor) are solved. A more abstract presentation of the principles of dynamic programming is then given followed by an exposition of its application to quite general optimal problems with three of the principle types of reactor, namely the stirred tank, the adiabatic bed and the tubular or batch reactor.
Protein‐Polymer Conjugates

This chapter focuses on the design and applications of protein-polymer conjugates. Protein-polymer conjugates are synthesized by conjugating a polymer chain or many polymer chains onto a protein. The site of conjugation, protein, polymer, and stoichiometry are important criteria when designing a protein-polymer conjugate. The important structural aspects and functions of proteins, such as hierarchical structure and activity, are discussed. The various methods of site-specific conjugation, “grafting to”, “grafting from” and cofactor reconstitution, are included along the pros and cons of each method. Conjugates synthesized by random conjugation are also discussed. The specific reactions used for protein attachment are not included, as numerous synthetic reviews exist; however, a broad overview of the field is presented. Novel conjugate structures can be synthesized by attaching synthetic peptide sequences onto polymers. In addition to design considerations, the range of applications from drug delivery systems to biosensors are discussed. This chapter aims to aid in furthering the knowledge and growth of the synergistic combination of proteins and polymers. Keywords: peptide-polymer conjugates; biomaterials; site-specific conjugation; random conjugation
Lattice models and N = 2 supersymmetry

We review the construction of exactly solvable lattice models whose continuum limits are N = 2 supersymmetric models. Both critical and off-critical models are discussed. The approach we take is to first find lattice models with natural topological sectors, and then identify the continuum limits of these sectors with topologically twisted N = 2 supersymmetric field theories. From this, we then describe how to recover the complete lattice versions of the N = 2 supersymmetric field theories. We discuss a number of simple physical examples and we describe how to construct a broad class of models. We also give a brief review of the scattering matrices for the excitations of these models.
Vulnerability of Manned Spacecraft to Crew Loss from Orbital Debris Penetration

Orbital debris growth threatens the survival of spacecraft systems from impact-induced failures. Whereas the probability of debris impact and spacecraft penetration may currently be calculated, another parameter of great interest to safety engineers is the probability that debris penetration will cause actual spacecraft or crew loss. Quantifying the likelihood of crew loss following a penetration allows spacecraft designers to identify those design features and crew operational protocols that offer the highest improvement in crew safety for available resources. Within this study, a manned spacecraft crew survivability (MSCSurv) computer model is developed that quantifies the conditional probability of losing one or more crew members, P(sub loss/pen), following the remote likelihood of an orbital debris penetration into an eight module space station. Contributions to P(sub loss/pen) are quantified from three significant penetration-induced hazards: pressure wall rupture (explosive decompression), fragment-induced injury, and 'slow' depressurization. Sensitivity analyses are performed using alternate assumptions for hazard-generating functions, crew vulnerability thresholds, and selected spacecraft design and crew operations parameters. These results are then used to recommend modifications to the spacecraft design and expected crew operations that quantitatively increase crew safety from orbital debris impacts.
Symmetry breaking in general relativity

Bifurcation theory is used to analyze the space of solutions of Einstein's equations near a spacetime with symmetries. The methods developed here allow one to describe precisely how the symmetry is broken as one branches from a highly symmetric spacetime to nearby spacetimes with fewer symmetries, and finally to a generic solution with no symmetries. This phenomenon of symmetry breaking is associated with the fact that near symmetric solutions the space of solutions of Einstein's equations does not form a smooth manifold but rather has a conical structure. The geometric picture associated with this conical structure enables one to understand the breaking of symmetries. Although the results are described for pure gravity, they may be extended to classes of fields coupled to gravity, such as gauge theories. Since most of the known solutions of Einstein's equations have Killing symmetries, the study of how these symmetries are broken by small perturbations takes on considerable theoretical significance.
Strip Intercropping Effects on Yield and Yield Components of Corn, Grain Sorghum, and Soybean

Strip intercropping of corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] and grain sorghum [Sorghum bicolor (L.) Moench] and soybean may be a viable alternative to monoculture cropping to help reduce soil erosion. Careful study of yields and yield components can add to understanding crop performance and contribute to design of more productive systems. Rainfed and irrigated experiments were conducted in eastern Nebraska from 1988 to 1990, on a Sharpsburg silty clay loam (fine, smectitic, mesic Typic Argiudoll), to quantify strip-intercropping effects on crop yields and yield components. Corn border-row and grain sorghum border-row yields next to soybean increased significantly compared with inside rows in the strips. Increased seed number and seed weight contributed to higher corn border-row yields, while only seed number increased in grain sorghum border rows. Soybean border-row yields were lower next to all corn strips and next to grain sorghum strips at the rainfed site. Soybean seed number was lower in border rows next to corn. Corn border-row increases in seed number and seed weight indicate that competition for resources was important in both reproductive and grain-filling periods; sorghum border-row increases in seed number suggest competition only in the reproductive period. Higher corn density in border rows may further exploit a competitive advantage with soybean in the reproductive period, perhaps increasing system productivity. Whole-system productivity of strip-intercropping systems was a maximum of 4% higher than monocultures of component crops, and gross returns did not differ between the two systems. If there is need to control soil erosion, strip intercropping can be equally profitable to monoculture if production costs are similar.
Micropulsations in the morning sector, 3. Simultaneous ground‐satellite observations of 10‐ to 45‐s period waves near L = 6.6

A search for simultaneous 10- to 45-s waves at the synchronous orbit at the location of ATS 1 and at Tungsten, Northwest Territories, Canada (near the foot of the ATS 1 field line), during 1969 resulted in the identification of only one event. This event occurred near 0900-1000 LT and was identified as a Pc 3 event. By combining 1967 data from College, Alaska (near the same L shell as ATS 1), with ATS 1 data, 90 simultaneous events were identified. Analysis of 60 of these events led to the conclusion that Pi 1 are rarely, if ever, observed on the magnetic equator at synchronous orbit, even when Pi 1 activity is present on the ground near the conjugate point. Pc 3, on the other hand, are common at synchronous orbit. A statistical study of the Pc 3 occurring at ATS 1 during simultaneous College wave activity indicated characteristics similar to those observed at ATS 6.
Black Studies and Political Ideology as Predictors of Self-Esteem A Call for a New Direction

This article assesses the relationship between enrollment in Black studies courses, political ideology, and self-esteem in Black college students. Although a number of studies have focused on racial identity and self-esteem, few have investigated how a race-first political consciousness among African Americans develops and whether it is related to healthier psychological outcomes. To elucidate the relationship between Black nationalism, Black studies courses, and self-esteem, 231 students from an historically Black college in the Southeast are sampled. Preliminary analysis indicates enrollment in Black studies courses is related to nationalism and self-esteem. However, subsequent regression analysis controlling for classification indicates enrollment in Black studies courses is not a significant predictor of self-esteem or Black nationalism. Black nationalism predicted self-esteem, and older African American students reported higher nationalism scores. The findings suggest early exposure to Black studies ...
Unique challenges with recent gamma spectroscopy measurements at Los Alamos National Laboratory

A variety of unique radioactive samples have been measured recently at Los Alamos National Laboratory (LANL) using an electrically-cooled high-purity germanium detector. In each case the purpose of the measurements included one or more of the following objectives: (1) an accurate determination of the isotopic weight fractions of different plutonium or uranium materials; (2) an accurate determination of the isotopic quantity in the absence of relevant calibration standards; and (3) a qualitative determination of various sample impurities for additional forensic information. This paper discusses how simple modifications to the PC-FRAM parameter sets enabled a better determination of the isotopic content of the following samples: (1) high-purity plutonium metal, (2) plutonium-beryllium (PuBe) neutron sources, (3) neutron-irradiated natural uranium, and (4) re-processed HEU fuel with elevated 236U content. The isotopic quantity in a variety of samples was determined using a combination of the Spectral Nondestructive Assay Platform (SNAP™) routine from Eberline Services and the Monte Carlo Neutral Particle (MCNP) code developed at LANL. The non-traditional sources that were quantified with these gamma ray modeling codes included dozens of neutron-irradiated targets of natural uranium, several plutonium-beryllium neutron sources, and three high-purity samples of plutonium metal.
Association of newly synthesized pro-opiomelanocortin with secretory granule membranes in pituitary pars intermedia cells

The prohormone, pro-opiomelanocortin (POMC) is synthesized on ribosomes, subsequently routed to the Golgi apparatus and finally packaged into secretory granules where it is processed to various biologically active hormones (α-melanotropin, adrenocorticotropin, β-endorphin and β-lipotropin). We report here that in frog and mouse pars intermedia cells, newly synthesized[3H]Arg-labeled POMC is associated with the secretory granule membrane prior to processing. This association with the secretory granule membrane may be related to the intracellular transport and packaging of POMC and/or the facilitation of processing of the prohormone within the organelle.
Do We Know How Happy We Are? On Some Limits of Affective Introspection and Recall

This paper aims to show thai widespread, serious errors in the self-assessment of affect are a genuine possibility-one worth taking very seriously. For we are subject to a variety of errors concerning the character of our present and past affective states, or "affective ignorance. "For example, some affects, particularly moods, can greatly affect the quality of our experience even when we are unable to discern them. 1 note several implications of these arguments. First, we may he less competent pursuers of happiness than is commonly believed, raising difficult questions for political thought. Second, some of the errors discussed ramify for our understanding of consciousness, including Ned Block's is controversial distinction between access consciousness and phenomenal consciousness. Third, empirical results based on self-reports about affect may be systematically misleading in certain ways.
Coagulation of microcrystalline cellulose dispersions

Abstract The coagulation effects on microcrystalline cellulose sols of simple ions, hydrolyzed metal ions, chelate complexes, and a series of alkylammonium chlorides differing in length of the hydrocarbon chain have been investigated. It was found that these sols are much more sensitive towards electrolytes than typical lyophilic colloids. The coagulation concentrations of simple monovalent counterions were even considerably lower than for many lyophobic sols. It was suggested that this is due to the second stability minimum as predicted by the theory of Derjaguin-Landau-Verwey-Overbeek (DLVO). Reversal of charge of the microcrystalline cellulose particles could be achieved neither with complex counterions nor with the surface-active ions employed. All these are efficient reversal-of-charge agents when added to “typical” lyophobic colloids.
The role of xanthine oxidase in oxidative damage caused by cytokines in cultured mouse hepatocytes

In the present study we have examined the potential role of xanthine oxidase (XO) in the intracellular oxidative stress induced by combinations of recombinant murine TNF alpha (rMuTNF alpha) and murine interferon-gamma (IFN gamma) in cultured mouse hepatocytes. IFN gamma alone and the combination of rMuTNF alpha and IFN gamma increased XO activity after a 4 hr exposure period. rMuTNF alpha alone increased XO activity only after 24 hr. At the later time point, the increased XO activity was accounted for by decreased XDH activity. However, the apparent conversion of XDH to XO cannot account for the early effects of rMuTNF alpha on hepatocyte function, particularly the onset of an oxidative stress (as indicated by efflux of GSSG from the hepatocytes). This effect is observed after two hours, and it is temporally the earliest sign of alteration of cellular function caused by rMuTNF alpha. Increased XO activity was not observed until 4 hr after treatment with rMuTNF alpha/IFN gamma. In addition, inhibition of XO activity with allopurinol did not ameliorate GSSG efflux from hepatocytes treated with the cytokines. However, the ATP depletion caused by the combination of rMuTNF alpha and IFN gamma and the cytotoxicity observed with the combined cytokines in cells pre-treated with BCNU (to inhibit glutathione reductase) was inhibited by allopurinol. These results show that the onset of oxidative stress in cultured mouse hepatocytes is not due to conversion of XDH to XO. However, events which follow the efflux of GSSG, such as ATP depletion and cytotoxicity in cells with impaired anti-oxidant defenses, may be partially due to increased XO activity, especially in cells treated with both rMuTNF alpha and IFN tau.
Asymmetric Supernovae from Magnetocentrifugal Jets

Strong toroidal magnetic fields generated in stellar collapse can generate magnetocentrifugal jets in analogy to those found in simulations of black hole accretion. Magnetocentrifugal jets may explain why all core collapse supernovae are found to be substantially asymmetric and predominantly bipolar. We describe two phases: the initial LeBlanc-Wilson jet and a subsequent protopulsar or toroidal jet that propagates at about the core escape velocity. The prompt LeBlanc-Wilson jets will produce an excess of neutron-rich matter and hence cannot be the common origin of supernova explosions; similar but less severe problems arise with the protopulsar jet that may be alleviated by partial evacuation along the axis by rotation. The jets will produce bow shocks that tend to expel matter, including iron and silicon, into equatorial tori. This may help to account for observations of the element distribution in Cas A. A magnetic "switch" mechanism may apply in rare instances (when there is low density and large magnetic field), with subsequent increase in the speed and collimation of the toroidal jet. The conditions that turn the magnetic switch "on" would yield a jet that propagates rapidly and with small opening angle through the star, depositing relatively little momentum. The result could be enough infall to form a black hole. A third, highly relativistic jet from the rotating black hole could catch up to the protopulsar jet after it has emerged from the star. The interaction of these two jets plausibly could be the origin of the internal shocks thought to produce γ-ray bursts and could explain the presence of iron lines in the afterglow. Recent estimates that typical γ-ray burst energy is ~3 × 1050 ergs imply either a very low efficiency for conversion of rotation into jets by the Blandford-Znajek mechanism or a rather rapid turnoff of the jet process even though the black hole still rotates rapidly. Magnetars and "hypernovae" might arise in an intermediate parameter regime of energetic jets that yield larger magnetic fields and provide more energy than the routine case, but that are not so tightly collimated that they yield failed supernova.
Intravenous Sympathetic Blockade: The Phentolamine Infusion Test

Abstract Abnormal coupling between primary sensory afferent and sympathetic efferent neurons has been documented in animal models of neuropathic and inflammatory pain. These models have been used to improve the understanding of similar pain states in humans. Therapies that modulate sympathetic nervous system function have been advocated for the treatment of chronic pain of diverse etiology. One such therapy, the phentolamine infusion test, reduces pain by pharmacologic antagonism of peripheral α-adrenergic receptors. Patients who show reduction in pain after phentolamine infusion may benefit from future therapies designed to modulate sympathetic tone or adrenergic receptor function. Copyright © 2001 by W.B. Saunders Company
Hepatitis C. A clinical update.

Hepatitis C virus is now known to be the causative agent for at least 90% of non-A, non-B hepatitis cases. In the few years since its characterization, much has been learned about this virus and the scope of its disease. It now appears that close to 100% of infections may become chronic, with delayed but potentially devastating consequences. The treatment options for hepatitis C remain limited and less than satisfactory. A vaccine seems to be a distant goal, but other strategies for treatment may be closer. For now, the best option remains prevention. ( Arch Surg. 1996;131:18-23)
Supraclavicular thoracotomy for diagnosis of apical lung and superior mediastinal lesions.

Abstract Despite the use of mediastinoscopy, anterior mediastinotomy, transcarinal biopsy, needle biopsy, and transbronchial fluoroscopic brushing, thoracotomy is necessary to obtain tissue for diagnosis in patients suspected of having carcinoma of the lung. A technique we have employed is exploratory thoracotomy, as described for the approach to cervical and upper dorsal sympathetic ganglion, with entrance into the pleural space through a supraclavicular incision. Five patients, 3 with marginal pulmonary function and 2 with brachial plexus and upper mediastinal or vertebral involvement, had tissue diagnosis of lung carcinoma by this method without postoperative complication. Supraclavicular thoracotomy offers a safe, easy, and definitive method of tissue diagnosis of apical lung and superior mediastinal lesions.
Creep relaxation for combined stresses

Abstract This paper develops a theory for predicting stress relaxation-time relations for creep in the case of combined stresses based on an assumed constant stress-creep-time relation. The accuracy of the theoretical prediction is checked experimentally by conducting some preliminary creep relaxation tests on thin-walled circular tubes subjected to combined axial tension and torsion. The material tested was an aluminium alloy 3S0 and the experiments were conducted at room temperature.
Upconversion under polychromatic excitation: Y2SiO5:Pr3+, Li+ converts violet, cyan, green, and yellow light into UVC

Abstract Due to their unique ability to amplify photon energies, upconversion (UC) materials are being studied for numerous potential applications to light-utilizing technologies. Many such uses of UC demand adequate conversion efficiency under low-power, broad spectrum irradiation; however, spectroscopic studies of UC phosphors have been most commonly conducted using monochromatic laser excitation that is resonant with the desired electronic transitions. In this study, we sought to elucidate the behavior of UC materials under polychromatic excitation by initiating visible-to-UV UC in a Pr3+-doped phosphor under multiple combined two-color excitation beams. Several wavelengths of light, which were not capable of producing UC emission when used alone, were found to contribute to UC when combined with other colors, indicating that polychromatic UC mechanisms warrant consideration in applications involving broad band excitation.
A spectrophotometric procedure for quantitation of antibody directed to bacterial antigens.

Abstract A spectrophotometric procedure was developed to study the reaction of whole Streptococcus mutans 6715 cells with purified IgG antibody directed to the group-specific antigen of these organisms. The nature of the reaction was studied by combining different concentrations of antibody with 108 formalin-killed S. mutans 6715 cells and monitoring the optical density at 530 nm periodically for up to 24 hr. The curves obtained by plotting the observed optical density values against time were characterized by three phases: an initial rise, a plateau and a fall. The optical density changes were related to the number and size of cell aggregates present at various times during the procedure. Aggregated cells, primarily those in intermediate-size complexes (21–150 cells) appeared to contribute to initial rise in optical density, while further changes appeared to most closely correspond to the formation and subsequent sedimentation of the larger-size complexes (> 150 cells). Apparent rate constants calculated for the formation of intermediate size aggregates did not significantly vary with antibody concentration, while the rate constants for large aggregate formation increased dramatically with increases in antibody concentration. Spectrophotometric analyses performed with 14 different antibody concentrations ranging from 7·6 to 380 μg/100 μl showed that a linear relationship existed, after 1 min of reaction, between the log of the antibody concentration and the change in optical density. This relationship, coupled with the demonstration that serum components did not contribute to the effects of antibody on bacterial cells, indicated that the concentration of antibody in immune serums could be measured. Comparison of the spectrophotometric procedure with direct elution of antibody from cells, using 5 different serum samples, showed a mean per cent difference between the 2 methods of 6·5% (range 0·9–16·1%). Further comparison of the spectrophotometric procedure with the reversed radial immunodiffusion technique (4 serums tested) showed a mean per cent difference of 10·4% (range 0·3–30·3%). The spectrophotometric procedure was at least as accurate as the other procedures utilized and had the distinct advantage of permitting determinations to be made after 1 min of reaction.
A Cross-Cultural Study on Sex-Role Stereotypes and Social Desirability.

Thirty-nine items of sex-role stereotype questionnaire from Broverman's study were used as the instrument to get three separate responses — male stereotype, female stereotype, social desirability — from 340 college students. Half of the subjects were American, half Chinese. The number of male and female subjects was equal. The major findings were as follows: (1) In rating female sex-role stereotype, American subjects described the female sex-role with more agentic and competent attributes, while Chinese subjects tended to describe the female sex-role with more warm and expressive attributes. (2) In both nations, there was a tendency for males to emphasize the male stereotype as more socially desirable, while the female subjects did not. (3) In both nations, there was a tendency for women to describe the female stereotype differently from males' description (liberated image vs. traditional image).
Urban stream denitrifier communities are linked to lower functional resistance to multiple stressors associated with urbanization

The microbial communities in urban stream ecosystems are subject to complex combinations of stressors. These same microbial communities perform the critical ecosystem service of removing excess reactive nitrogen. We asked whether the denitrifying microbial communities in urban streams differ in their functional resistance to common urban stressors from communities from nonurban streams. We exposed inocula from a highly polluted urban stream and a nearby nonurban stream to three different stressors, added alone and in combination. Stressors represent the common urban impacts of thermal pollution (10°C), trace metal exposure (ionic silver (Ag+)), and salinization (addition of NaCl). We used reduction in nitrite (NO2 −) concentrations under anaerobic conditions as a proxy for denitrification potential. Nonurban stream denitrifying microbial communities were more diverse than their urban counterparts. Denitrification potential for both communities was unaffected by exposure to any individual stressor. However, denitrification rates by the less diverse urban microbial inoculum decreased in response to combined heavy metal and salt stress, while nonurban communities were unaffected. These findings support the hypothesis that higher diversity may confer greater functional resistance in response to multiple stressors and do not support the idea that stressful conditions select for communities that are functionally resilient to multiple stressors.
Downregulation of Tyrosinase Activity in Human Melanocyte Cell Cultures by Yohimbine

Treatment of human melanocyte cell cultures with the alpha-2 adrenergic receptor antagonist yohimbine results in a marked down-regulation of tyrosinase activity. A 30% decrease occurs within 12 h of exposure of cells to yohimbine (100 μM), and by 48 h tyrosinase activity in treated melanocytes is less than a fifth that of control cultures. The inhibition is dose dependent and occurs in human melanocytes derived from either black or white skin types, and also in mouse melanoma cells. The yohimbine-induced decrease in tyrosinase activity is reversible, with enzyme levels returning to 90% of control values 48 h after removal of drug. Although tyrosinase activity is markedly suppressed by yohimbine, the compound has no effect on cell proliferation, cellular translation, or DNA synthesis. Treatment of melanocyte cultures with yohimbine blocks the increase in tyrosinase activity by either 3-isobutyl-1-methylxanthine, dibutyryl cAMP, or forskolin. Results of cAMP immunoassays, show that intracellular levels of the cyclic nucleotide are unaffected in cells treated with yohimbine. Tyrosinase inhibition by yohimbine does not involve a decrease in substrate availability since tyrosine uptake studies show that yohimbine has no effect on the amount of tyrosine entering the cell. Incubation of a melanosome-enriched fraction with yohimbine does not cause a lowering of tyrosinase activity, suggesting that an intact cell is required for yohimbine action. In addition, tyrosinase extracts show no reduction in activity when incubated directly with yohimbine, indicating that the drug does not act as a direct inhibitor of the enzyme. Finally, results of western immunoblotting show that yohimbine does not significantly lower the amount of tyrosinase protein in human melanocytes. These findings suggest that yohimbine acts through an as yet unidentified signaling pathway to lower the catalytic activity of pre-existing tyrosinase molecules present in melanocytes.
Towards noise-resilient document modeling

We introduce a generative probabilistic document model based on latent Dirichlet allocation (LDA), to deal with textual errors in the document collection. Our model is inspired by the fact that most large-scale text data are machine-generated and thus inevitably contain many types of noise. The new model, termed as TE-LDA, is developed from the traditional LDA by adding a switch variable into the term generation process in order to tackle the issue of noisy text data. Through extensive experiments, the efficacy of our proposed model is validated using both real and synthetic data sets.
Be‐Chalcogenide Alloys for Improved R‐G‐B LEDs: BexZnyCd1–x–ySe on InP

We report the molecular beam epitaxy growth and characterization of Be x Zn y Cd 1-x-y Se (x ≤ 0.2) layers on InP substrates. Good optical properties and high crystalline quality were established using photoluminescence and X-ray diffraction measurements. The dependence of the Be x Cd 1-x Se band gap energy on composition was investigated and fit to the quadratic equation: Eg = 1.78(1 - x) + 5.6x - 2.6x(1 - x) with a bowing parameter of 2.6 eV. Our results indicate that Be x Zn y Cd 1-x-y Se is an attractive quantum well material for application in visible light emitters.
Quantification of the initial phases of rapid brain enlargement in the chick embryo.

Rapid brain enlargement requires a hydraulic mechanism in the chick embryo. Such a mechanism involves a closed, fluid-filled system that generates positive pressure. For the chick embryo this study determined when rapid brain enlargement begins, assessed the relative contributions of cavity expansion and tissue growth to overall brain enlargement, and evaluated mathematical models of overall brain enlargement and expansion and growth of the component parts. Three to five embryos were collected at each Hamburger and Hamilton state (11, 12, 14, 16, and 18) and processed for paraffin serial sectioning. Brain growth was determined over a 24-hr period (stages 11-18) by calculating volumes from area measurements of sections of brains from individual embryos by using a computerized image-analysis system. Statistical analysis indicated that a linear model adequately described cavity expansion, and a linear model was rejected for the description of tissue growth and total brain enlargement. At the onset of brain enlargement, the cavity expands faster than the tissue grows; but after 12 hr the reverse is true. Initially (i.e., at stage 11), the cavity accounts for 60% of the total brain volume and tissue for 40%. At stages 12-16, cavity and tissue contribute 50% each. Finally at stage 18, cavity accounts for 55% and tissue for 45%. In order to better distinguish changes in cavity expansion and tissue growth over the 24-hr period studied, this period was divided into four intervals (I-IV). The rates of both cavity expansion and tissue growth increase between intervals I and II, decrease between intervals II and III, and increase between intervals III and IV.(ABSTRACT TRUNCATED AT 250 WORDS)
Further investigation of the effect of framework catenation on hydrogen uptake in metal-organic frameworks.

Hydrogen-sorption studies have been carried out for the catenation isomer pairs of PCN-6 and PCN-6′ (both have the formula of Cu3(TATB)2, where TATB represents 4,4′,4′′-s-triazine-2,4,6-triyl-tribenzoate with a formula of C24H12N3O6). Inelastic neutron scattering (INS) studies reveal that the initial sites occupied by adsorbed H2 are the open Cu centers of the paddlewheel units with comparable interaction energies in the two isomers. At high H2 loadings, where the H2 molecules adsorb mainly on or around the organic linkers, the interaction is found to be substantially stronger in catenated PCN-6 than in noncatenated PCN-6′, leading to much higher H2 uptake in the isomer with catenation. Hydrogen sorption measurements at pressures up to 50 bar demonstrate that framework catenation can be favorable for the enhancement of hydrogen adsorption. For example, the excess hydrogen uptake of PCN-6 is 72 mg/g (6.7 wt %) at 77 K/50 bar or 9.3 mg/g (0.92 wt %) at 298 K/50 bar, respectively, and that for PCN-6′ is 42 m...
Effects of the prostaglandin synthesis inhibitor, indomethacin on estrogen- and estrogen plus progesterone-induced sexual receptivity in ovariectomized rats

Abstract Implants of crystalline PGE 2 in the basal preoptic-anterior hypothalamic areas stimulates high levels of sexual receptivity in ovariectomized, estrogen-primed rats. Indomethacin, which blocks the synthesis of PGE 2 , failed to inhibit either estrogen- or estrogen plus progesterone-induced receptivity. Neither intracerebral nor subcutaneous administration of indomethacin diminished the display of steroid induced reproductive behavior without also causing a depression in open-field activity, and in some cases, causing gastrointestinal problems and even death. These results suggest that prostaglandin synthesis is not a required step in the mechanism by which estrogen and progesterone exert their behavioral effects. The possibility that PGE 2 and LH-RH synthesis and/or release might contribute to a collateral mechanism for the induction of sexual receptivity was discussed.
Update on gemcitabine and docetaxel combination therapy for primary and metastatic sarcomas.

Purpose of reviewThe combination of fixed-dose-rate gemcitabine and docetaxel has become an established treatment option for advanced uterine leiomyosarcoma and has demonstrated efficacy in nonleiomyosarcoma histology soft-tissue sarcomas. The activity of this regimen in advanced uterine leiomyosarc
High-average-power, 100-Hz-repetition-rate, tabletop soft-x-ray lasers at sub-15-nm wavelengths

Efficient excitation of dense plasma columns at 100-Hz repetition rate using a tailored pump pulse profile produced a tabletop soft-x-ray laser average power of 0.1 mW at \ensuremath{\lambda} = 13.9 nm and 20 \ensuremath{\mu}W at \ensuremath{\lambda} = 11.9 nm from transitions of Ni-like Ag and Ni-like Sn, respectively. Lasing on several other transitions with wavelengths between 10.9 and 14.7 nm was also obtained using 0.9-J pump pulses of 5-ps duration from a compact diode-pumped chirped pulse amplification Yb:YAG laser. Hydrodynamic and atomic plasma simulations show that the pump pulse profile, consisting of a nanosecond ramp followed by two peaks of picosecond duration, creates a plasma with an increased density of Ni-like ions at the time of peak temperature that results in a larger gain coefficient over a temporally and spatially enlarged space leading to a threefold increase in the soft-x-ray laser output pulse energy. The high average power of these compact soft-x-ray lasers will enable applications requiring high photon flux. These results open the path to milliwatt-average-power tabletop soft-x-ray lasers.
Public good or commercial opportunity? Case studies in remote sensing commercialization ☆

The U.S. Government is once again attempting to commercialize the Landsat program and is asking the private sector to develop a next generation mid-resolution remote sensing system that will provide continuity with the thirty-year data archive of Landsat data. Much of the case for commercializing the Landsat program rests on the apparently successful commercialization of high-resolution remote sensing activities coupled with the belief that conditions have changed since the failed attempt to commercialize Landsat in the 1980s. This paper analyzes the economic, political and technical conditions that prevailed in the 1980s as well as conditions that might account for the apparent success of the emerging high-resolution remote sensing industry today. Lessons are gleaned for the future of the Landsat program.
Laser Applications To Heterogeneous Catalysis: Reactant Excitation And Product Diagnostics

Irradiation of gaseous NO2 with the 488 nm line of an argon ion laser during its reaction with C2H4 over a Pt catalyst at 250 C resulted in up to a fourfold increase in the CO2 product yield. This enhancement is believed to result from the reaction of vibrationally excited NO2 with adsorbed C2H4 or a species derived from it. The observed effect disappeared after a period of time due to surface poisoning. Hydroxyl radicals have been detected leaving the surface of Pt and Rh-Pt catalysts during the reaction of H2 and 02 at 600-800 C. The OH radical was detected by its fluorescence at 340 nm induced by a dye laser, both in the gas phase and in an Ar matrix at 10 K. The activation energies for OH production from Pt and Rh-Pt surfaces have been determined.
Finite element simulations of Tennessee marble under plane strain laboratory testing : Effects of sample-platen friction on shear band onset

Abstract We use the finite element method to analyze a non-associated Drucker–Prager elastic–plastic material relation for Tennessee marble under plane strain laboratory test conditions. We study how the sample–platen interface boundary conditions affect the development of stress and strain in the sample and prediction for the onset of shear banding according to the Rudnicki–Rice theory. Samples that are bonded with the platen (corresponding to an infinite coefficient of friction (COF)) have all their maximum interface stresses at the outside upper corner of the test piece. When the COF is finite the stresses are not maximum in the corner but just inside of it, with the exception of the in-plane lateral normal stress, which has its maximum along the vertical centerline. Both the interface COF and the aspect ratio (the height/width ratio) affect the whole-sample axial stress–strain curves and the onset of localization. For an aspect ratio of 2.25, simulations with different COFs have whole-sample axial nominal stress versus strain curves that are coincident until late in the loading program. Then, in the vicinity of localization (near peak), these curves separate slightly from each other and the onset of localization occurs at different stress and strain values. Specifically, the stress and strain at localization onset decrease with increasing COF (from 0.01 to infinity in separate simulations) from the values for the frictionless interface. Although we focus on the 2.25 aspect ratio, our analyses with three other ratios (1.875, 1.5, and 1.0) with fixed COF show that localization onset occurs at progressively higher axial nominal stress and strain as the aspect ratio is decreased. Lastly, we find that a lower sample aspect ratio facilitates localization near the outside of the sample and close to the sample–platen interface, while the higher aspect ratio favors the onset of shear banding in the sample center. Our results demonstrate that modest variations in sample–platen friction do not significantly alter the nominal stress–strain curves but they can affect the onset and location of localization.
Realization of the English postvocalic [voice] contrast in F1 and F2

Abstract Before a [−voice] coda, F1 is higher for monophthongs but lower for /a i / than before [+voice]. We test the hypothesis that this is due to hyperarticulation before voiceless consonants (Thomas, J. Phonetics 88 (2000) 1). Experiment 1, with 16 American English speakers, found the /a i / pattern of more peripheral F1 and F2 in the offglides /ɔ i e i aʊ/ as well, showing that it is part of the realization of [−voice]. The diphthong nuclei were less affected than the offglides. Experiment 2, with different 16 American English speakers, collected “tight”-”tide” judgments of a synthetic stimulus in which offglide F1, offglide F2, and nuclear duration were varied independently. “Tight” responses were facilitated by lower F1, by higher F2, and by shorter nuclei. Log-linear analysis showed that the three factors contributed independently, and that F2 was a stronger cue than F1 in terms of logits per Bark. Experiment 3, with a different 16 speakers, replicated Experiment 2 for “ate”-”aid” judgments (/e i / having shown the smallest effects in Experiment (1)). Thus, [−voice] is correlated with, and cued by, peripheralization of diphthong offglides.
Cognitive aspects of survey methodology

Since its initiation in the early 1980s, research into cognitive aspects of survey methods (CASM) has made considerable progress in illuminating the cognitive and communicative processes underlying survey responding. This article reviews key themes and developments, notes strengths and shortcomings and places the contributions to this special issue in this context. Copyright © 2007 John Wiley & Sons, Ltd.
Life Course Social Science Perspectives on the GLBT Family

Abstract The life course perspective in the social sciences focuses on the place of generation-cohorts in understanding social life. Emphasizing shared understanding of self and society among a group of persons born in some adjacent birth years (often a decade) and the impact of the experience of certain events (a reminiscence bump) taking place across the early adult years, this approach to the study of social life and social change emphasizes social timing and role changes in understanding the course of life. The life course perspective is used in this discussion in understanding sexual minority families including both families in which an offspring self-defines as GLBT across the years of young adulthood, and families in which a parent self-identifies as GLBT, and which includes offspring of one or both partners. Issues in family formation and morale of family members are explored from this life course perspective emphasizing time, social change and the role of the state as factors influencing sexual m...
Convergence of subdifferentials under strong stochastic convexity

We show that if a sequence of random functions satisfies strong stochastic convexity with respect to a parameter, and if the sequence converges pointwise with probability one, then any sequence of elements extracted from the subdifferentials of the functions in the sequence will converge to the subdifferential of the limiting function, again with probability one. This result holds with no differentiability assumption on the limiting function, and even if the limiting function is itself random. It thus extends earlier work, in particular results by Glynn and by Hu. One application is in proving an extended form of strong consistency for infinitesimal perturbation analysis IPA when suitable convexity properties hold.
Ultrastructural study of globular inclusions in human skeletal muscle mitochondria.

Limb muscle biopsies from a patient with Luft's disease and a patient with a slowly progressive neuromuscular disorder since infancy revealed by conventional electron microscopy the presence of globular inclusions in the mitochondria as one of the most prominent morphological findings.
Further Studies of Potassium Deficiency on the Electrocardiograms of Chickens

Abstract STURKIE (1950) studied the effects of acute potassium deficiency on the electrocardiograms of chicks. The young chicks began dying within ten days and most of them were dead by 21 days. Before death, most of the chicks revealed abnormal ECG’s, which included second degree A-V block, complete A-V block, S-A block, sinus slowing, sinus arrhythmia, and premature nodal and ventricular systoles. The most common abnormality was second degree A-V block. The results of the present study are similar to those previously reported except that two new abnormalities were observed and are described. PROCEDURE Day-old White Leghorn cockerels were placed on a purified diet almost or completely deficient in K. The ration was as follows: casein, 25 parts; gelatin, 8.5; cornstarch, 30; dextrose, 25; cellulose, 5; minerals, 6; and vitamins, 0.5 parts. The diet contained no fat, but growth in the control birds, which received 0.21 percent potassium, was adequate. The . . .