cssi/SciSciGPT-SciSciNet huggingface dataset:
The reaction of oxalyl thiolesters with nucleophiles, especially thiols☆

Abstract Since there is evidence that oxalyl thiolesters (RSCOCOO − ) are present in animal cells, and possibly may participate in the control of metabolism, the present study was undertaken to characterize their reactivity with nucleophiles so that one could gain a better understanding of how they might be affecting the activities of enzymes. At 25°C and neutral pH, N -acetyl- S -oxalyl-2-aminoethanethiol (NAC-S-Ox) reacts rapidly with cysteamine (2-aminoethanethiol) to give N -acetylcysteamine and N -oxalylcysteamine. Under similar conditions, other aminothiols, such as cysteine, homocysteine, penicillamine, and cysteine ethyl ester, also react rapidly with NAC-S-Ox, but non-thiol-containing amines, such as alanine, alanine ethyl ester, glycine, and S -methylcysteine, react more than four orders of magnitude less rapidly. The aminothiol reactions apparently proceed by rate-determining oxalyl transfer to the thiol followed by a rapid intramolecular S - to N -oxalyl migration. The reactions follow second-order kinetics with the thiolate anion being the reactive nucleophile. At 25°C and ionic strength 1.0 m , k N , defined in the equation, rate = k N [RS − ][NAC-S-Ox], has the following values ( m −1 s −1 ) for the anion of the reacting thiol: cysteamine, 170; cysteine, 260; cysteine ethyl ester, 76; homocysteine, 380. Rate data for the reaction of NAC-S-Ox with hydroxylamine, imidazole, hydroperoxide, and hydroxide were also obtained. The reaction of S -oxalyl- p -thiocresol with thiol anions under the same conditions gives the following values for k N ( m −1 s −1 × 10 −3 ): glutathione, 5.6; N -acetylcysteamine, 3.7; pantetheine, 4.8; 8-mercaptooctanoic acid, 4.5; 6-mercaptooctanoic acid, 1.0; dihydrolipoic acid, 8.2. These results indicate that oxalyl transfers from oxalyl thiolesters to thiol anions occur more than two orders of magnitude more rapidly than corresponding acetyl transfers, and that under physiological conditions any in vivo oxalyl thiolester would equilibrate within minutes with virtually every thiol in the cell, including those attached to enzymes. Consequently, it is proposed that one mechanism by which oxalyl thiolesters may function in vivo to alter the catalytic activities of enzymes is to covalently modify enzymic thiols by acylation with an oxalyl group.
Caspase-9, Bcl-XL, and Apaf-1 Form a Ternary Complex

Genetic analysis of apoptosis in the nematode Caenorhabditis elegans has revealed the cell death machine to be composed of three core interacting components. CED-4 (equivalent to mammalian Apaf-1) is a nucleotide binding molecule that complexes with the zymogen form of the death protease CED-3, leading to its autoactivation and cell death. CED-9 blocks death by complexing with CED-4 and attenuating its ability to promote CED-3 activation. An equivalent ternary complex was found to be present in mammalian cells involving Apaf-1, the mammalian death protease caspase-9, and Bcl-XL, an anti-apoptotic member of the Bcl-2 family. Consistent with a central role for caspase-9, a dominant negative form effectively inhibited cell death initiated by a wide variety of inducers.
Novel kinetic texture features for breast lesion classification on dynamic contrast enhanced (DCE) MRI

Dynamic contrast enhanced (DCE) MRI has emerged as a promising new imaging modality for breast cancer screening. Currently, radiologists evaluate breast lesions based on qualitative description of lesion morphology and contrast uptake profiles. However, the subjectivity associated with qualitative description of breast lesions on DCE-MRI introduces a high degree of inter-observer variability. In addition, the high sensitivity of MRI results in poor specificity and thus a high rate of biopsies on benign lesions. Computer aided diagnosis (CAD) methods have been previously proposed for breast MRI, but research in the field is far from comprehensive. Most previous work has focused on either quantifying morphological attributes used by radiologists, characterizing lesion intensity profiles which reflect uptake of contrast dye, or characterizing lesion texture. While there has been much debate on the relative importance of the different classes of features (e.g., morphological, textural, and kinetic), comprehensive quantitative comparisons between the different lesion attributes have been rare. In addition, although kinetic signal enhancement curves may give insight into the underlying physiology of the lesion, signal intensity is susceptible to MRI acquisition artifacts such as bias field and intensity non-standardness. In this paper, we introduce a novel lesion feature that we call the kinetic texture feature, which we demonstrate to be superior compared to the lesion intensity profile dynamics. Our hypothesis is that since lesion intensity is susceptible to artifacts, lesion texture changes better reflect lesion class (benign or malignant). In this paper, we quantitatively demonstrate the superiority of kinetic texture features for lesion classification on 18 breast DCE-MRI studies compared to over 500 different morphological, kinetic intensity, and lesion texture features. In conjunction with linear and non-linear dimensionality reduction methods, a support vector machine (SVM) classifier yielded classification accuracy and positive predictive values of 78% and 86% with kinetic texture features compared to 78% and 73% with morphological features and 72% and 83% with textural features, respectively.
Germanium on Silicon Lasers and Detectors

This paper discusses the most recent advances of Germanium photodetectors and lasers that can be monolithically integrated into a Silicon CMOS process.
Ruthenium(II) Anilido Complex Containing a Bisphosphine Pincer Ligand: Reversible Formation of Amidinate Ligands via Intramolecular C-N Bond Formation

The reaction of the octahedral anilido complex (PCP)Ru(CO)(NHPh)(PMe3) with acetonitrile produces the amidinate complex (PCP)Ru(CO){N(H)C(Me)N(Ph)}. Mechanistic studies indicate that the reaction p...
Desolvation map of the i-face of phospholipase A2

Abstract The changes in the microenvironment of the Trp-3 on the i-face of pig pancreatic IB phospholipase A 2 (PLA2) provide a measure of the tight contact (Ramirez and Jain, Protein Sci. 9, 229–239, 1991) with the substrate interface during the processive interfacial turnover. Spectral changes from the single Trp-substituent at position 1, 2, 6, 10, 19, 20, 31, 53, 56 or 87 on the surface of W3F PLA2 are used to probe the Trp-environment. Based on our current understanding only the residue 87 is away from i-face, therefore all other mutants are well suited to report modest differences along the i-face. All Trp-mutants bind tightly to anionic vesicles. Only those with Trp at 1, 2 or 3 near the rim of the active site on the i-face cause significant perturbation of the catalytic functions. Most other Trp-mutants showed
Grasping Mechanisms With Self-Centering and Force-Balancing Characteristics

This paper presents grasping mechanism configurations that are self-centering with balanced reaction forces, and develops the design principles, models, and analysis methods of achieving these characteristics in compliant mechanisms. The configurations emulate the self-centering and balanced actuation force characteristics exhibited by hydraulic disc-brake systems. Purely mechanical grasping systems, in which both the mechanism and the object being grasped are rigidly attached to ground, require 2 degrees of freedom in the grasping mechanism. It is shown that compliant configurations can exhibit the balanced-force behavior as well as rigid-link mechanisms.© 2005 ASME
The Influence of Others on the Vacation Experience: An Ethnographic Study of Psychographics, Decision Making, and Group Dynamics Among Young Travelers

The vacation experience is often enjoyed in the company of others. Whereas scholars have focused on the consumer behaviors of mature travelers, young travelers have received less attention. The present study explores customer-to-customer interactions among young travelers (in their 20s and 30s) within a European tour-group setting. Furthermore, it attempts to understand the influence such travelers have on one another. The decision-making patterns, role of the tour guide, group dynamics, and psychographic preferences are studied from an ethnographic approach. Results indicate that the young travel segment is not as homogeneous as previously conceived. Notable differences in activities, interests, and opinions were observed. Additionally, several cases of en-route group purchase decisions were observed. This article draws upon the concept of compatibility management to advocate for a more targeted approach in appealing to this particular market segment. Conclusions are made regarding the differences among ...
A new model of skin injury.

SummaryTopical application of a vasoconstrictor agent and xylene modifies in the rat the usual skin responses to subsequent applications of various phlogogens. The production of this state is believed to involve the peripheral neurohumoral system.
The high-affinity receptor for IgE

Many cells of the immune system have cell-surface receptors that bind IgE with low afhmity [FCE receptor (FcER) II] (Delespesse et al, this issue, pp 506512). In contrast, the high-aifmity receptor for IgE (FcsRI) is found exclusively on the surface of mast cells and basophils. By coupling the presence of allergens with the cellular response, FcR Metzger et al, Annu Rev Immunoll986,4:41!+470).
Pitfalls in atmospheric correction of ocean color imagery: how should aerosol optical properties be computed?: reply to comment

Gordon [Appl. Opt.42, 542 (2003)] argues that use of external rather than internal mixing when aerosol optical properties are computed will not seriously affect atmospheric correction of ocean color imagery, in spite of the fact that top of the atmosphere reflectances computed with the two approaches differ significantly as shown by Yan et al. [Appl. Opt.41, 412 (2002)]. We apply an algorithm for simultaneous retrieval of aerosol optical properties and chlorophyll concentrations to demonstrate that use of the internal-mixing approach leads to atmospheric corrections that differ significantly from those obtained with the more realistic external-mixing approach. For relative humidities of 90% or more, the differences in retrieved aerosol optical properties and chlorophyll concentrations, incurred by application of the internal-mixing approach, become unacceptably large.
Are MSM Willing to SMS for HIV Prevention

Text messaging is a potential HIV-prevention tool for men who have sex with men (MSM), specifically young MSM and MSM of color. To determine the willingness of MSM to receive text messages as part of an HIV-prevention intervention, we administered an online survey to MSM recruited from MySpace.com, which included questions about mobile phone ownership and willingness to participate in a future text message–based HIV research study. Of participants, 85% (n = 5,378) reported owning a mobile phone and 49% (n = 2,483) of mobile phone owners reported being willing to receive text messages in a future HIV research study. Black and Hispanic men were more willing than White non-Hispanic men to receive text messages. Men with a college degree were less willing to receive texts than men with a high school level of education, and men >22 years old were less likely to be willing to receive texts than those younger than 22 years of age. The authors' findings demonstrate that willingness to receive text messages as par...
A comparison of a needle-free injection system for local anesthesia versus EMLA® for intravenous catheter insertion in the pediatric patient

Placement of IV catheters is a painful and stressful procedure for children. J-Tip is a needle-less Food and Drug Administration approved injection system that can be used for delivery of local anesthetic before IV cannulation. In this study, we compared the effectiveness of J-Tip versus eutectic mixture of local anesthetics (EMLA) to facilitate IV cannulation and provide adequate analgesia before IV placement. Children 7-19 years of age (n = 116) were randomized to receive 0.25 mL of 1% buffered lidocaine with J-Tip (n = 57) or 2.5 g of EMLA (n = 59) before IV cannulation. Measurements of success of cannulation (number of attempts for IV placement) and pain (0-10 visual analog scale) at application of local anesthetic and at cannulation were performed. There was a significant (P = 0.0001) difference in pain ratings during IV cannulation between EMLA (median = 3) and the J-Tip (median = 0). Eighty-four percent of patients reported no pain at the time of J-Tip lidocaine application compared to 61% in the EMLA group at the time of dressing removal (P = 0.004). We did not find differences in the number of attempts for IV cannulation. J-Tip application of 1% buffered lidocaine before IV cannulation is not painful and has better anesthetic effectiveness compared with EMLA.
Proteasome-Mediated Processing of Nrf1 Is Essential for Coordinate Induction of All Proteasome Subunits and p97

Summary Background Proteasome inhibitors are widely used in the treatment of multiple myeloma and as research tools. Additionally, diminished proteasome function may contribute to neuronal dysfunction. In response to these inhibitors, cells enhance the expression of proteasome subunits by the transcription factor Nrf1. Here, we investigate the mechanisms by which decreased proteasome function triggers production of new proteasomes via Nrf1. Results Exposure of myeloma or neuronal cells to proteasome inhibitors (bortezomib, epoxomicin, and MG132), but not to proteotoxic or ER stress, caused a 2- to 4-fold increase within 4 hr in mRNAs for all 26S subunits. In addition, p97 and its cofactors (Npl4, Ufd1, and p47), PA200, and USP14 were induced, but expression of immunoproteasome-specific subunits was suppressed. Nrf1 mediates this induction of proteasomes and p97, but only upon exposure to low concentrations of inhibitors that partially inhibit proteolysis. Surprisingly, high concentrations of these inhibitors prevent this compensatory response. Nrf1 is normally ER-bound, and its release requires its deglycosylation and ubiquitination. Normally ubiquitinated Nrf1 is rapidly degraded, but when partially inhibited, proteasomes carry out limited proteolysis and release the processed Nrf1 (lacking its N-terminal region) from the ER, which allows it to enter the nucleus and promote gene expression. Conclusions When fully active, proteasomes degrade Nrf1, but when partially inhibited, they perform limited proteolysis that generates the active form of Nrf1. This elegant mechanism allows cells to compensate for reduced proteasome function by enhancing production of 26S subunits and p97.
Key Resources for student affairs professionals in learning-centered community colleges

This chapter, aimed at both new community college student affairs professionals and experienced practitioners hoping to further develop their skills, provides resources and information about the expanding focus on student learning, translating student development theory into practice, and assessing student learning outcomes.
Unusual features of the distribution of Radon-222 in the bottom waters of the continental slope of the Mid-Atlantic Bight: Hydrodynamic implications

Abstract 222Rn was measured in the near-bottom waters of the continental slope of the Mid-Atlantic Bight. Separate measurements of the 222Rn supported by dissolved 226Ra allowed the excess 222Rn that is derived from the underlying sediments to be distinguished. Measurements of production of 222Rn by the sediments were used to calculate fluxes of 222Rn from sediments that would be expected as a result of molecular diffusion. On the upper slope and on the lower slope excess 222Rn standing crops were, respectively, greater than and consistent with fluxes of radon from sediments by molecular diffusion as are typical of most ocean environments. On the middle slope, however, observed excess 222Rn concentrations and standing crops were significantly lower than what would be expected from the calculated fluxes from the underlying sediments. This unusual feature of low radon concentrations on the middle slope is referred to as the low-radon zone (LRZ). This LRZ was always present over several years and seasons, but was variable in intensity (excess-radon concentration and standing crop) and in location on the slope. Low concentrations of suspended particulate matter and low current velocities observed by others in the same region are consistent with low mixing as a possible cause of the LRZ. Radon profile shapes and recent work by others on near bottom mixing due to interactions between topography and internal waves, however, suggest that high mixing due to internal waves is a more likely cause of the LRZ.
Integrating ergonomic factors into the decision to retire

Abstract A large body of research describes the factors that influence a worker in the decision to retire. However, the decision processes used by employees have received far less attention. We propose a theoretical model, based on well-established turnover decision process research, which incorporates ergonomics as a critical factor in the decision to retire. Ergonomic factors are proposed as distal factors that play a role in a retirement decision. We propose that they influence worker health and job attitudes, which in turn influence more proximal antecedents of retirement, leading up to the act of retiring.
GROWTH OF LATE-HATCHED, COMPETITIVELY DISADVANTAGED NESTLING HOUSE WRENS RELATIVE TO THEIR OLDER, LARGER NESTMATES

Abstract We compared the growth of late-hatched, competitively disadvantaged nestlings to that of their first-hatched, larger nestmates in 12 asynchronously hatching broods in a Wyoming population of House Wrens (Troglodytes aedon). Upon hatching, late-hatched nestlings weighed, on average, 48% as much as their heaviest nestmate (range 38–60%). Late-hatched nestlings gained significantly less mass per day (0.23 g, on average) than first-hatched nestmates between the ages of 3 and 7 days when mass gain is most rapid. Late-hatched nestlings also showed a strong tendency to grow tarsi more slowly than first-hatched nestmates over the same time period (mean difference: 0.16 mm/d). Primary feathers of late-hatched nestlings, however, grew slightly but not significantly more slowly those of first-hatched nestmates (mean difference: 0.05 mm/d). Reduced rates of mass gain and tarsus growth but normal rates of feather growth have been observed in competitively disadvantaged nestlings in several other passerine spe...
Knowing the limits of one’s understanding: The development of an awareness of an illusion of explanatory depth

Adults overestimate the detail and depth of their explanatory knowledge, but through providing explanations they recognize their initial illusion of understanding. By contrast, they are much more accurate in making self-assessments for other kinds of knowledge, such as for procedures, narratives, and facts. Two studies examined this illusion of explanatory depth with 48 children each in grades K, 2, and 4, and also explored adults' ratings of the children's explanations. Children judged their understanding of mechanical devices (Study 1) and procedures (Study 2). Second and fourth graders showed a clear illusion of explanatory depth for devices, recognizing the inaccuracy of their initial impressions after providing explanations. The illusion did not occur for knowledge of procedures.
Quaternary Murid Rodents of Timor Part I: New Material of Coryphomys buehleri Schaub, 1937, and Description of a Second Species of the Genus

Abstract Large collections of fragmentary animal bones excavated from archaeological contexts in East Timor between 1968 and 2002 provide new material referable to the recently extinct, gigantic murine genus Coryphomys. We document the upper and lower dentition and palatal anatomy of C. buehleri Schaub, 1937, and identify and name a second species of Coryphomys, based on differences in molar size and morphology and skeletal robusticity. Alternative interpretations of the observed morphological and metric variability (sexual dimorphism, resource-based polymorphism, sample heterochroneity) are each carefully assessed and rejected, and we conclude that the genus comprised two species of approximately similar body size. Preserved cranial elements of both species of Coryphomys feature a high degree of anatomical specialization, including an unusual elaboration of the maxillary sinus complex. Though the specialized anatomy of Coryphomys invites consideration of its phylogenetic relationships, this exercise is h...
Causes of early human population growth

The archaeological record indicates large increases in human population coincident with the emergence of food production about 10,000 years ago. The cause of the growth is unclear. Extreme views attribute the change to increases in the birth rate or to decreases in the death rate. Many argue that sedentism led to improved ovarian function and higher fertility through higher caloric intakes or reduced activity levels. Similarly, shortened lactation periods may have reduced birth spacing and increased fertility. Others attribute the rise in population to decreases in mortality, arguing that the evidence from skeletal populations indicates improvements in health and the expectation of life at birth, though others use the same evidence to argue that mortality increased. An analysis presented here draws on findings that indicate substantial increases in the survival of young children as populations switch from nomadic to sedentary lives. Projections indicate that this improvement in child survival is so critical that it may be followed by substantially larger decreases in survival at later ages, yet result in higher population growth rates and reduced expectation of life at birth. Increases in the birth rate are not necessary for population growth, even when overall mortality increases. Large increases in overall mortality can be associated with large increases in population. Because positive population growth can occur while the expectation of life at birth declines, this analysis shows that this summary statistic is not an appropriate indicator of population fitness.
CFD Implementation of a novel carbon-phenolic-in-air chemistry model for atmospheric re-entry

Recent and future re-entry vehicle designs use ablative material as the main component of the heat shield of their thermal protection systems. In order to properly predict the behavior of the vehicle, it is imperative to take into account the gases produced by the ablation process when modeling the reacting flow environment. In the case of charring ablators, where an inner resin is pyrolyzed at a relatively low temperature, the composition of the gas expelled in the boundary layer is complex and might lead to thermal chemical reactions that cannot be captured with simple flow chemistry models. In order to obtain better predictions, a proper gas flow chemistry model needs to be included in the CFD calculations. Recent calculations showed that extensive differences are found in boundary layer composition and heat fluxes, both convective and radiative, when previously published models were used on a realistic problem. Recently, a more complete model was proposed, which includes an extensive set of kinetic rates, taken from the combustion community. Using this model, CFD calculations of the Stardust re-entry are presented. The results clearly demonstrate the need to account for many more species in the flow field than the ones that are expected to be present at the surface.
Identification of Peach Rootstock Cultivars by RAPD Markers

Eighteen peach rootstock cultivars, most of Prunus persica (L.) Batsch, were screened for diagnostic random amplified polymorphic DNA (RAPD) markers using synthetic decamer oligonucleotide primers. Twenty of the 80 primers were informative, and 40 amplified DNA bands from the informative primers were selected as RAPD markers. Based on combined banding patterns, all 18 rootstock cultivars were identified with only six of the 20 informative primers. Cluster analysis of the 18 peach rootstock cultivars using 40 RAPD markers produced a dendrogram of genetic relatedness in good agreement with their putative pedigrees. The first major bifurcation in the dendrogram divided these rootstock cultivars into two groups according to their resistance or suscep- tibility to root-knot nematodes (Meloidogyne incognita (Kofoid and White) Chitwood and M. javanica (Treub) Chitwood).
The Party Whip Organizations in the United States House of Representatives.

In the literature on political parties in the United States Congress two points are usually stressed. First, it is said that the political party label lacks a precise programmatic content because “party government” in the British sense is absent in the American Congress. Second, however, it is contended that the party label is the single most important and reliable attribute in predicting the voting behavior of a Senator or Representative.Between these two contentions lies a sizeable area of unexplored territory. If party is the best predictive device in analyzing voting behavior in Congress then, despite the lack of “party government,” the party machinery in both houses must have effects that deserve study. Professor Huitt has suggested the necessity and importance of this kind of study: “… the preoccupation with reform has obscured the fact that we have no really adequate model of party leadership as it exists in Congress, and that none can be constructed because we lack simple descriptions of many of the basic working parts of the present system.” Huitt himself and a few others have filled some of these gaps.
Locally Constrained Support Vector Clustering

Support vector clustering transforms the data into a high dimensional feature space, where a decision function is computed. In the original space, the function outlines the boundaries of higher density regions, naturally splitting the data into individual clusters. The method, however, though theoretically sound, has certain drawbacks which make it not so appealing to the practitioner. Namely, it is unstable in the presence of outliers and it is hard to control the number of clusters that it identifies. Parametrizing the algorithm incorrectly in noisy settings, can either disguise some objectively present clusters in the data, or can identify a large number of small and nonintuitive clusters. Here, we explore the properties of the data in small regions building a mixture of factor analyzers. The obtained information is used to regularize the complexity of the outlined cluster boundaries, by assigning suitable weighting to each example. The approach is demonstrated to be less susceptible to noise and to outline better interpretable clusters than support vector clustering alone.
A VLSI architecture for DFT

In this paper, a one-dimensional fully pipelined architecture for computing discrete-Fourier transform (DFT) is presented. It consists of an array of N basic cells (BC's) and requires N clock cycles for a N-point DFT. The architecture is modular and makes possible computation of a 2N-point transform by a simple cascade of two identical N-point transform chips. The architecture is simple and regular in structure and is hence very attractive for VLSI implementation. >
Student Information Resource Utilization in Problem-Based Learning

Purpose: To examine the profile of medical students’ resource use in a longitudinal problem-based learning course and to examine patterns of change. Method: Over a six-month period, 116 students indicated on resource checklists which resources they had used for independent research of learning issues identified in their problem-based learning sessions. On the checklist, resources were categorized as printed, electronic, human, or physical evidence (i.e., models, demonstrations). Results: Over the six-month period, the percentage of use (number of times a resource category was used / number of weekly reports submitted) declined from 64.0% printed, 81.7% electronic, and 4.3% physical to 44.0%, 69.8%, and 3.9%, respectively. Use of human resources increased from 29.1% to 36.6%. Use of a variety of resources (resources from ³2 categories of resources) also declined.
The E6 protein of human papillomavirus type 16 binds to and inhibits co-activation by CBP and p300

The co-activators CBP and p300 are important for normal cell differentiation and cell cycle progression and are the targets for viral proteins that dysregulate these cellular processes. We show here that the E6 protein from the oncogenic human papillomavirus type 16 (HPV-16) binds to three regions (C/H1, C/H3 and the C-terminus) of both CBP and p300. The interaction of E6 with CBP/p300 was direct and independent of proteins known to bind the co-activators, such as p53. The E6 protein from low-risk HPV type 6 did not interact with C/H3 or the C-terminus but associated with the C/H1 domain at 50% of the level of HPV-16. HPV-16 E6 inhibited the intrinsic transcriptional activity of CBP/p300 and decreased the ability of p300 to activate p53- and NF-kappaB-responsive promoter elements. Interestingly, some mutations in HPV-16 E6 abrogated C/H3-E6 interactions, but did not alter the ability of E6 to associate with the C/H1 domain, suggesting that these modified proteins could be used to delineate the functional significance of the C/H1 and C/H3 domains of CBP/p300.
Children's asthma hospitalizations and relative risk due to nitrogen dioxide (NO2): effect modification by race, ethnicity, and insurance status.

Abstract Background This study explores the role of race, ethnicity, and insurance status in modifying the effects of air pollution on children’s asthma hospitalizations in Phoenix, Arizona (US) between 2001 and 2003. While controlling for weather, interactions between nitrous dioxide (NO 2 ) and race, ethnicity, and insurance status are used to predict relative risk for subgroups of children. Methods The generalized logit regression model for nominal categorical data within a multinomial likelihood framework was used. This model is specifically suited to small counts and the reporting of 95% confidence intervals for the odds ratio of hospital admission for one group as compared to another. The odds ratio is known to approximate relative risk for rare events. Results Several significant findings were found for race, ethnicity, and insurance status as modulators for the effect of NO 2 on children’s risk for asthma hospitalization: (1) children without insurance have 1.4 (95% CI: 1.1–1.8) times higher risk of asthma admissions than those with private insurance at exceedances of 0.02 parts per million (ppm) of NO 2 above the seasonal mean; the same finding holds for children without insurance as compared to those with Medicaid; (2) black children have 2.1 (95% CI: 1.3–3.3) times higher risk of hospitalization than Hispanic children at seasonal mean NO 2 levels, but this disproportionate risk shrinks to 1.7 with exceedances of 0.02 ppm of NO 2 above the seasonal mean. Specific to finding (1) among those children without health insurance, Hispanic children have 2.1 (95% CI: 1.1–3.8) times higher risk of hospitalization than white children. Among all Hispanic children, those without health insurance have 1.9 (95% CI: 1.3–3.0) times greater risk than those with private insurance; the same finding holds for Hispanic children without insurance as compared to Hispanic children with Medicaid. Specific to finding (2), among children with private insurance, the disproportionate risk of black children as compared to Hispanic children is magnified by a factor of 1.3 (95% CI: 1.0–1.8) for exceedances of 0.02 ppm of NO 2 above the seasonal mean. Conclusions Although we cannot confirm a cause–effect relationship, this analysis suggests that increasing insurance enrollment for all children, and specifically Hispanic children, may reduce their disproportionate risk from exceedances of air pollution. There are few black children in Phoenix, so further studies are needed to investigate the increasing risk of black children with private insurance as compared to Hispanics at exceedances of NO 2 .
Bypass Angioplasty Revascularization Investigation (BARI): Baseline clinical and angiographic data

This report presents baseline clinical and angiographic data from the Bypass Angioplasty Revascularization Investigation (BARI), a multicenter international trial assessing the relative efficacy of percutaneous transluminal coronary angioplasty (PTCA) versus coronary artery bypass graft surgery (CABG) in selected patients with multivessel coronary artery disease. PTCA is commonly performed in patients with multivessel coronary artery disease, yet its long-term efficacy in comparison to CABG is unknown. From August 1988 through August 1991, 1,829 qualifying patients with multivessel disease suitable for either procedure were randomized to PTCA or CABG; sample size estimates were based on anticipated 5-year mortality. Two registry populations were also defined for follow-up: (1) 2,013 patients eligible for randomization but not randomized; and (2) 422 patients considered by angiography as unsuitable for randomization. Patients randomized in BARI were at relatively high risk for subsequent cardiac events: 39% were > or = 65 years old, 55% had prior myocardial infarction, 69% presented with unstable angina or non-Q wave myocardial infarction, and 43% had 3-vessel coronary artery disease. Patients randomized to PTCA and CABG were equally matched in all the important baseline variables. The randomized and the eligible but not randomized groups were similar in most respects. However, the nonrandomized group had a higher proportion with college education; fewer with a history of myocardial infarction, heart failure, diabetes, and smoking; and a somewhat better average ejection fraction. At the 3-month follow-up, PTCA had been performed more commonly in the nonrandomized eligible patients, especially those with 2-vessel disease.(ABSTRACT TRUNCATED AT 250 WORDS)
Processing characteristics, structure development, and properties of uni and biaxially stretched poly(ethylene 2,6 naphthalate) (PEN) films

Poly(ethylene 2,6, naphthalene dicarboxilate), PEN, is very similar to poly(ethylene terephthalate), PET, in its chemical structure and was, therefore, expected to exhibit similar processing characteristics. We, however, observed a few problems during stretching of PEN, the most important of which was necking behavior at 145°C, which is between Tg (117°C) and Tcc (195°C). This is usually observed in PET only when it is stretched close to or below Tg. At temperatures between Tg and Tcc (cold crystallization temperature) PET stretches rather uniformly. The temperature window for film stretching appears to be rather wide, but our results indicate that this is not the case. Films stretched to high stretch ratios become uniform due to propagation and final disappearance of necks as a result of stress hardening. Our attempts at stretching these films at higher temperatures indicated that necking is eliminated, but so is stress induced crystallization, which causes stress hardening (unless high stretching rates are employed). The presence of stress hardening is essential for obtaining high quality, uniform films of these polymers. In addition, at high temperatures thermally activated crystallization which starts dominating the structure development, detrimentally affects the general appearance of the films. In brief, the PEN films we investigated have a narrower processing window than was anticipated based on their thermal behavior alone. At elevated temperatures the films are sensitive to the rate of stretching even more than typical PET processed at comparable conditions. The uniformity of the films depends on the stretch ratio, stretching mode, ratio(s) and rates and temperature. WAXS studies on the films indicate that the macromolecules packed into the low temperature crystal modification. In addition, WAXS pole figure studies suggest that naphthalene planes preferentially orient parallel to the film surface during biaxial stretching. The biaxially stretched films were observed to exhibit a bimodal chain orientation as evidenced by pole figure analysis of the (010) planes.
The Overshoot Phenomena in Single Crystals of Cu-15 at% Al Tested in Tension. II. Orientation and Temperature Dependence of the Overshoot

Overshooting in Cu-15 at% Al single crystals was studied as a function of quenching temperature, testing temperature, and initial tensile axis orientation. Overshooting was found to be independent of orientation and test temperature but the degree of overshoot appeared to increase with increasing quench temperature. It was concluded that the overshoot was not a direct function of the stacking fault energy in the range of 5 to 10 erg/cm2 for a Cu-15 at% Al alloy. A model for overshoot was developed based on the collapse of Lomer-Cottrell dislocations under the line tension of bowed out conjugate dislocation segments. Das Uberschwingen in Cu-15 at% Al-Einkristallen wurde als Funktion der Abschrecktemperatur, der Versuchstemperatur und der Orientierung der ursprunglichen Spannungsachse untersucht. Das Uberschwingen ist unabhangig von der Orientierung und der Versuchstemperatur, aber der Grad des Uberschwingens scheint mit wachsender Abschrecktemperatur zu wachsen. Es wird geschlossen, das das Uberschwingen keine direkte Funktion der Stapelfehlerenergie im Bereich 5 bis 10 erg/cm2 fur eine Cu-15% Al-Legierung ist. Ein Modell fur das Uberschwingen wurde entwickelt, das auf dem Zusammenbruch der Lomer-Cottrell-Versetzungen unter der Linienspannung von Schleifen konjugierter Versetzungssegmente beruht.
Computing extreme subspaces using Mirsky theorem

Extreme eigenpairs computation is of considerable interest in signal processing and estimation. Thus problem of simultaneous computation of the smallest and largest eigenvalues and the corresponding eigenvectors of a symmetric matrix is considered. The proposed methods are derived from optimizing cost functions which are chosen to have optimal values at vectors that are linear combinations of extreme eigenvectors of a given matrix. Dynamical systems that converge to extreme eigenvectors are derived from necessary optimality conditions which are given in terms of a gradient of certain cost functions over a Stiefel manifold. Numerical examples are given to examine the convergence.
Enhancement of benzo(a)pyrene diol epoxide mutagenicity by sulfite in a mammalian test system

Sulfur dioxide, a ubiquitous air pollutant, is a co-carcinogen for benzo[a]pyrene (BP). We have demonstrated previously that the interaction between sulfite, the physiological form of sulfur dioxide, and (+/-) -7r,8t-dihydroxy-9t,10t-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (anti-BPDE), the ultimate carcinogenic form of BP, results in an enhanced mutagenic effect in Salmonella typhimurium strains TA98 and TA100. We report here that this same co-mutagenic effect of sulfite occurs in a mammalian cell line. Treatment of Chinese hamster V79 cells with 50 nM anti-BPDE, a concentration on the linear portion of the dose-response, resulted in a four-fold increase in mutations at the hprt locus relative to the spontaneous rate. When V79 cells were exposed to 1 or 10 mM sulfite immediately prior to the addition of anti-BPDE, the mutation rate increased by 73% and 210%, respectively, over that elicited by anti-BPDE alone. Sulfite itself was moderately cytotoxic, but caused no increase in mutation over the spontaneous rate. Characterization of the dose- and time-dependance of this enhancement of diol epoxide mutagenicity by sulfite closely resembled the effects seen previously in the bacterial system. In particular, enhancement by sulfite was evident when sulfite was added to the cells between 60 min and 1 min prior to the addition of the diol epoxide. Concurrent addition of sulfite and the diol epoxide attenuated the enhancement, and the effect was lost altogether when sulfite was added 10 min after the diol epoxide. The specificity of this effect of sulfite was shown by comparison with sulfate, which at concentrations of either 1 or 10 mM exhibited modest cytotoxicity, but neither was directly mutagenic nor able to enhance the mutagenic effect of anti-BPDE. Binding studies with labeled anti-BPDE showed that the addition of 10 mM sulfite increased binding of anti-BPDE to DNA by over 43%, corresponding to the observed increase in mutant frequency. Interestingly, this difference in level of DNA modification was not apparent after 30 min to 2 h exposures, but only emerged at the 4 h time point. The 4 h point was routinely used for all mutagenicity studies. Binding of anti-BPDE-derived materials to cellular RNA was not altered by 10 mM sulfite. The emergence of increased DNA modification at the latest time point suggests either a more prolonged period of active DNA binding than would occur with diol epoxide, or a difference in the ability to recognize and clear specific DNA adducts. Both possibilities are discussed in regard to the observed formation of 7r,8t,9t-trihydroxy-7,8,9,10-tetrahydrobenzo[a] pyrene-10c-sulfonate (BPT-10-sulfonate) in those incubations. BPT-10-sulfonate is a relatively stable BP derivative which retains the ability to covalently modify DNA. The role of this derivative in the enhancement of diol epoxide mutagenicity by sulfite is strongly suggested by these data.
Can group- and issue-related factors predict choice shift ? A meta-analysis of group decisions on life dilemmas

The phenomenon of choice shift in group decisions has been extensively researched and documented. Existing reviews on choice shift have primarily focused on the theoretical explanations of the phen...
Evaluating the Benefits of Peri-Urban Agriculture:

By uniting literature from farmland preservation, growth management, food systems, economics, bioengineering, and environmental studies, this article provides an overview and valuation of the services that farms provide for urban areas. This article first analyzes the mission statements of 130 nationally accredited land trusts to ascertain the criteria used in preserving farmland. Land trusts present uniform preference for parcels that provide ecosystem services, wildlife habitat, viewsheds, local heritage, and agricultural productivity. The list of benefits provided by land trusts was compared to a literature review drawing from farmland amenity, agritourism, farmland preservation, and ecosystems studies to reveal the range of market values for the various benefits of farmland. The market value of farmland services varies from -$37,541 to 124,000 per acre depending on the method of analysis and location of the farm. This research has strong implications for land-use planning, economic opportunities, and ecosystems infrastructure in peri-urban areas.
Spherical harmonic synthesis and least squares computations in satellite gravity gradiometry

The computational requirements in the simulations of geopotential estimation from satellite gravity gradiometry are discussed. Fast algorithms for spherical harmonic synthesis and least squares accumulation on a vectorizing supercomputers are presented. Using these methods, in a test case estimation of 2595 coefficients of a degree and order 50 gravity field, sustained program execution speeds of 275 Mflops (87 % peak machine speed) on a single processor of a CRAY Y-MP were achieved, with spherical harmonics computation accounting for less than 1 % of total cost. From the results, it appears that brute-force estimation of a degree and order 180 field would require 537 Million Words of memory and 85 hours of CPU time, assuming mission duration of 1 month, and execution speed of 1 Gflops. Both memory size and execution speed requirements are within the capabilities of modern multi-processor supercomputers.
THE ANALYSIS OF PICOGRAM QUANTITIES OF RARE EARTH ELEMENTS IN NATURUAL WATERS

Recent developments in analytical instrumentation, combined with the demonstrated utility of the rare earth elements (REE) as tracers in natural waters, have encouraged a large number of researchers to attempt low-level REE determinations in natural waters. However, there are few, if any, sufficiently detailed guides available that outline the essential requirements for producing reliable REE data for natural waters. In this chapter we attempt to provide such a guide, aimed primarily at those researchers considering entering this research area for the first time.
Circadian organization of the mammalian retina

The mammalian retina contains an endogenous circadian pacemaker that broadly regulates retinal physiology and function, yet the cellular origin and organization of the mammalian retinal circadian clock remains unclear. Circadian clock neurons generate daily rhythms via cell-autonomous autoregulatory clock gene networks, and, thus, to localize circadian clock neurons within the mammalian retina, we have studied the cell type-specific expression of six core circadian clock genes in individual, identified mouse retinal neurons, as well as characterized the clock gene expression rhythms in photoreceptor degenerate rd mouse retinas. Individual photoreceptors, horizontal, bipolar, dopaminergic (DA) amacrines, catecholaminergic (CA) amacrines, and ganglion neurons were identified either by morphology or by a tyrosine hydroxylase (TH) promoter-driven red fluorescent protein (RFP) fluorescent reporter. Cells were collected, and their transcriptomes were subjected to multiplex single-cell RT-PCR for the core clock genes Period (Per) 1 and 2, Cryptochrome (Cry) 1 and 2, Clock, and Bmal1. Individual horizontal, bipolar, DA, CA, and ganglion neurons, but not photoreceptors, were found to coordinately express all six core clock genes, with the lowest proportion of putative clock cells in photoreceptors (0%) and the highest proportion in DA neurons (30%). In addition, clock gene rhythms were found to persist for >25 days in isolated, cultured rd mouse retinas in which photoreceptors had degenerated. Our results indicate that multiple types of retinal neurons are potential circadian clock neurons that express key elements of the circadian autoregulatory gene network and that the inner nuclear and ganglion cell layers of the mammalian retina contain functionally autonomous circadian clocks.
Communication Problems in Maltreated Children: A Tutorial:

Speech/language problems have frequently been noted in the delayed development of maltreated children. Yet, the exact role which abuse and/or neglect plays in the communication disorder is often un...
An Innocent Abroad? John Dewey and International Politics

Dewey's refusal to abandon his strong belief in the democratic ideal, which must materialize not via powerful political elites but rather through publicly created institutions and full participation of ordinary citizens, has been grossly misunderstood. Using Dewey's critics' own arguments that purport to show Dewey intentionally, or naively, disregarded the role of power in the relations of communities, Westbrook brings examples to reinforce the contrary view. Dewey's adherence to the view that war must be universally outlawed and sanctioned was targeted precisely on the international political elites in order to reduce their domination and to maintain the real power within the hands of the citizens.