cssi/SciSciGPT-SciSciNet huggingface dataset:
Specification of the logit model: The case of valuation of nonmarket goods☆

Abstract We address the proper specification of the logit model for estimation of nonmarket commodity demand. Economic theory is used to show the conditions which must be met by the logit functional form if it is to yield valid estimates of welfare change measures and demand relationships. An empirical example is used to illustrate the argument. Recreational boating data were collected using the contingent valuation method (CVM) in Texas. In one instance the demand curve is positively sloped due to the specific functional form chosen. The estimated demand curve for the theoretically preferred functional form has the expected negative slope.
Anterior thoracic surgical approaches in the treatment of spinal infections and neoplasms.

Background Thoracic surgeons are commonly consulted to provide anterior thoracic exposure for infection and malignant neoplasms involving the thoracolumbar spine. These cases can present significant technical and management challenges secondary to the underlying pathology, associated anatomic inflammation, and impaired functional status. In this study, we review the perioperative outcomes in patients undergoing anterior spinal exposure for infection and neoplasm. Methods 130 consecutive patients (61 women, 69 men) undergoing corpectomy, debridement, or debulking for osteomyelitis (n = 50) or neoplasms (n = 80) with decompression/stabilization at a single institution were analyzed. Primary endpoints included morbidity, mortality, and perioperative neurologic outcomes. Results The mean age was 61.1 years. A cervical/sternotomy (n = 8) approach was used for levels C7 to T2, thoracotomy (n = 79) for levels T3 to T10, and thoracoabdominal (n = 43) for T11 to L2 involvement. Primary spinal neoplasms (n = 22, 16.9 %) and metastases (n = 58, 44.6%) were treated with corpectomy and prosthetic stabilization and were associated with increased operative time (310 vs 243 minutes, p = 0.02) and blood loss (825 vs 500 mL, p = 0.002). Osteomyelitis was associated with longer hospital stays (12 vs 7 days, p Conclusions Anterior spinal exposure represents an important modality in facilitating the treatment of patients with osteomyelitis, pathologic fractures, and spinal cord compression syndromes. These procedures are associated with a significant risk of morbidity and mortality, but they are effective in achieving spinal stabilization and alleviating neurologic symptoms.
Polymer sol-gel composite inverse opal structures.

We report on the formation of composite inverse opal structures where the matrix used to form the inverse opal contains both silica, formed using sol–gel chemistry, and poly(ethylene glycol), PEG. We find that the morphology of the inverse opal structure depends on both the amount of PEG incorporated into the matrix and its molecular weight. The extent of organization in the inverse opal structure, which is characterized by scanning electron microscopy and optical reflectance data, is mediated by the chemical bonding interactions between the silica and PEG constituents in the hybrid matrix. Both polymer chain terminus Si–O–C bonding and hydrogen bonding between the polymer backbone oxygens and silanol functionalities can contribute, with the polymer mediating the extent to which Si–O–Si bonds can form within the silica regions of the matrix due to hydrogen-bonding interactions.
On the Comparison of Observed and GCM Simulated Climate Ensembles

Abstract Within the sampled climate ensemble framework for describing the climate, objective univariate statistical tests are presented which permit a straightforward assessment of the extent to which observed and GCM simulated climates agree or differ with respect to various first- and second-moment measures (i.e., ensemble averages and standard deviations) of the climate. As an example of this approach, the vertically averaged transient beat flux, (??)¯V′T′ is considered as a basic climate element and ensemble averages and standard deviations of this climate element are objectively compared fox. the same number of samples from a global data set assembled by A. Oort of GFDL and from sets of 2.5 and 5° resolution realizations with a GCM developed several years ago at NCAR. It is found that the degree of agreement between observed and simulated climate is highly dependent on the geographical location, the statistical moment used as the climate measure and whether zonally averaged or grid-point values const...
Exploring XP for scientific research

Can we successfully apply XP (Extreme Programming) in a scientific research context? A pilot project at the NASA Langley Research Center tested XPs applicability in this context. Since the cultural environment at a government research center differs from the customer-centric business view, eight of XPs 12 practices seemed incompatible with the existing research culture. Despite initial awkwardness, the authors determined that XP can function in situations for which it appears to be ill suited.
Early earth: Arsenic and primordial life

Some modern microorganisms derive energy from the oxidation and reduction of arsenic. The association of arsenic with organic cellular remains in 2.7-billion-year-old stromatolites hints at arsenic-based metabolisms at the dawn of life.
Cell polarity: overdosing on PCPs.

Summary Several spatial cues combine to influence cell polarity within the plane of the Drosophila wing epithelium, orienting two separable mechanisms of short-range intercellular communication, one utilizing the ‘core' polarity proteins, and another utilizing the protocadherins Dachsous and Fat, and the atypical myosin Dachs.
Toward building models of community college persistence: A logit analysis

Logit modeling was developed to explore the persistence of community college students. Independent variables included student demographic characteristics, purpose for enrolling, intention to return, frequency of informal interaction with faculty, and satisfaction with the college. Four separate models posited in this study indicate that persistence was a function of sex, purpose for enrolling, and intention to return. A posited model of academic integration indicated that measures of academic integration, including grade-point average, number of hours spent studying each week, and frequency of informal interaction with faculty were independent of persistence. A synopsis of the connections between the findings reported here and conceptual models of persistence focusing on four-year colleges and universities is presented.
Toxic feeding deterrents from the tropical marine alga Caulerpa bikinensis (chlorophyta)

Abstract Three new monocyclofarnesol-derived sesquiterpenoids with toxic and feeding deterrence properties have been isolated from the tropical green alga Caulerpa bikinensis from Palau. Structure assignments for these new compounds are based upon spectral studies in comparison with related monocyclic sesquiterpenoids.
The Shaping of EU-Mercosur Relations: From Altruism to Pragmatism and Liberalism to Illiberalism

Deeply-embedded norms of liberalism and protectionism alongside EU policies focusing on promoting development and regional integration have shaped EU-Mercosur relations. These stand in stark contrast to the policies of the US, the historic hegemon in the region. This paper utilizes historical institutionalism to understand how the liberal tenets of EU competition policy and the protectionism of Common Agricultural Policy (CAP) have affected EU-Mercosur relations. Particular foci include Spain’s role in spearheading efforts to promote EU-Latin American relations and the way EU competition policies directed against monopolies in Europe spurred increased investment in Latin America, especially the Southern Cone. The latter prompted the EU to forge closer ties with Mercosur, encouraged cooperation and development programs and spurred regional integration and liberal trade regimes in Latin America.
Do monetary policy shocks matter in the G-7 countries? Using common identifying assumptions about monetary policy across countries

Abstract This paper suggests an identified VAR model that identifies monetary policy actions for the G-7 countries without encountering empirical puzzles such as the price puzzle and the liquidity puzzle. Using the model, the effects of monetary policy shocks are examined for the postwar period. Monetary policy shocks have significant effects on output in the short run. However, the contribution of monetary policy shocks to output fluctuations is relatively small – monetary policy shocks are not the major sources of postwar G-7 output fluctuations.
Coexistence Mechanism Using Dynamic Fragmentation for Interference Mitigation between Wi-Fi Bluetooth

In this paper, we present a non-collaborative coexistence mechanism using dynamic fragmentation that functions very well at the Wi-Fi in the presence of Bluetooth interference. The proposed scheme tries to optimize MAC layer packet length such that the Wi-Fi device has better chance to avoid the interference caused by Bluetooth devices. The mechanism dynamically adjusts the fragmentation level based on the current packet error rate (PER). We developed an analytical model that provides the MAC the necessary information (in terms of PER) to decide the right time for further packet fragmentation. The developed model is also employed to measure the throughput of the Wi-Fi device. Simulations are also performed to validate the developed model. We show that our coexistence mechanism could significantly improve the performance of Wi-Fi in both throughput and transmission delay, though there is only slight performance improvement at the Bluetooth side.
Detonation discrimination and feature saliency using a near-infrared focal plane array and a visible CCD camera

This research investigates the classification of battlespace detonations, specifically the determination of munitions type and size using temporal and spectral features from near-infrared (NIR) and visible wavelength imagers. Key features from the time dependence of fireball size are identified for discriminating various types and sizes of detonation flashes. The five classes include three weights of trinitrotoluene (TNT) and two weights of an enhanced mixture, all of which are uncased and detonated with 10% C-4. Using Fisher linear discriminant techniques, these features are projected onto a line such that the projected points are maximally clustered for the different classes of detonations. Bayesian decision boundaries for classification are then established on class-conditional probability densities and are tested using independent test data. Feature saliency and stability are determined by selecting those features that best discriminate while requiring low variations in class-conditional probability densities and high performance in independent testing. Given similar conditions, the most important and stable feature is the time to the maximum fireball area in the near-infrared wavelength band (0.6 to 1.7 microns). This feature correctly discriminates between TNT and ENE about 90% of the time, whether weight is known or not. The associated class-conditional probability densities separate the two classes with a Fisher ratio of 2.9±0.3 and an area under the receiver operating characteristic, AROC, of 0.992. Also, tmp achieves approximately 54% success rate at discerning both weight and type.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Sol → gel → glass: I. Gelation and gel structure

Abstract The mechanisms of gel formation in silicate systems derived from metal alkoxides were reviewed. There is compelling experimental evidence proving, that under many conditions employed in silica gel preparation, the resulting polysilicate species formed prior to gelation is not a dense colloidal particle of anhydrous silica but instead a solvated polymeric chain or cluster. The skeletal gel phase which results during desiccation is, therefore, expected to be less highly crosslinked than the corresponding melted glass, and perhaps to contain additional excess free volume. It is proposed that, during gel densification, the desiccated gel will change to become more highly crosslinked while reducing its surface area and free volume. Thus, it is necessary to consider both the macroscopic physical structure and the local chemical structure of gels in order to explain the gel to glass conversion.
Current-driven magnetization dynamics in magnetic multilayers

We show that spin-polarized current flowing through a ferromagnet leads to both coherent and incoherent magnetic excitations. We describe these excitations by an effective magnetic temperature rather than a coherent precession as in the popular spin-torque model. Our model reproduces the essential features of the experiments, and gives several predictions that distinguish it from the spin-torque model.
Asian Americans Have Greater Prevalence of Metabolic Syndrome Despite Lower Body Mass Index

Asian Americans have greater prevalence of metabolic syndrome despite lower body mass index
Studies of residual ridge resorption. Part II. The relationship of dietary calcium and phosphorus to residual ridge resorption

Abstract This report presents results of an original investigation of the relationship between dietary calcium and phosphorus and alveolar bone resorption in edentulous patients. The diets of subjects with minimal bone resorption were compared with the diets of subjects with severe alveolar destruction. The results indicate a positive correlation among low calcium intake, calcium/phosphorus imbalance, and severe ridge resorption. Relationships among actual volume intake of these minerals, recommended allowances, and clinical findings were described. Emphasis was placed on the importance of considering dietary factors in the diagnosis and treatment of prosthodontic problems which arise from the excessive resorption of residual ridges.
Effects of Rain on Traffic Operations on Florida Freeways

Although the correlation between traffic variables and weather appears to be intuitive, quantifying the effects that weather, especially rain, has on driver response in travel speeds and traffic demands is needed to evaluate practical aspects of traffic operations. Previous studies have researched driver responses to inclement weather on freeways located in northern regions of the United States and Canada. However, driver familiarity with local weather conditions is a factor that should be considered in determining inclement weather effects on traffic variables. The focus of this research was to examine driver response to rain precipitation on freeways located in the southeastern regions of the United States to determine whether results from previous studies were general indicators or location specific in nature. To study the impacts of rain precipitation on hourly mean speeds and traffic volumes, hourly weather data and traffic sensor data were collected for two freeway segments in Jacksonville, Florida....
Lipopolysaccharide induces endoplasmic store Ca2+-dependent inflammatory responses in lung microvessels.

The pulmonary microvasculature plays a critical role in endotoxin-induced acute lung injury. However, the relevant signaling remain unclear. Specifically the role of endothelial Ca2+ in the induction of endotoxin-mediated responses in lung microvessels remains undefined. Toward elucidating this, we used the isolated blood-perfused rat lung preparation. We loaded microvessels with the Ca2+ indicator, Fura 2 AM and then determined Ca2+ responses to infusions of lipopolysaccharide (LPS) into the microvessels. LPS induced a more than two-fold increase in the amplitude of cytosolic Ca2+ oscillations. Inhibiting inositol 1,4,5 trisphosphate receptors on endoplasmic reticulum (ER) Ca2+ stores with Xestospongin C (XeC), blocked the LPS-induced increase in the Ca2+ oscillation amplitude. However, XeC did not affect entry of external Ca2+ via plasma membrane Ca2+ channels in lung microvascular endothelial cells. This suggested that LPS augmented the oscillations via release of Ca2+ from ER stores. In addition, XeC also blocked LPS-mediated activation and nuclear translocation of nuclear factor-kappa B in lung microvessels. Further, inhibiting ER Ca2+ release blunted increases in intercellular adhesion molecule-1 expression and retention of naive leukocytes in LPS-treated microvessels. Taken together, the data suggest that LPS-mediated Ca2+ release from ER stores underlies nuclear factor-kappa B activation and downstream inflammatory signaling in lung microvessels. Thus, we show for the first time a role for inositol 1,4,5 trisphosphate-mediated ER Ca2+ release in the induction of LPS responses in pulmonary microvascular endothelium. Mechanisms that blunt this signaling may mitigate endotoxin-induced morbidity.
SU‐FF‐T‐107: Selective Extended Field IMRT Can Protect Larynx and Adequately Treat the Lower Neck Lymph Nodes in Head and Neck Cancer

Objectives: Radiation dose to the larynx has been a major concern in the treatment of head and neck cancer. The use of splitting field (SF) IMRT can improve the dose to the larynx but it may result in inadequate tumor coverage and dosimetric uncertainties at the matchline. In this study, we propose a selective extended field (SEF) method to avoid the use of splitting field while reducing the larynxdose and achieving the adequate tumor coverage. Materials and Methods: Five nasopharyngeal patients with the gross tumor volume extended to the lower neck were treated with extended field (EF)‐IMRT. SEF IMRT plans were created by extending only three anterior and anterior oblique beams to the supraclavicular region while the other fields were restricted to the superior of the vocal cord. For comparison, SF‐IMRT plans were also created and matched with the conventional AP field. All plans were compared based on the tumor volume coverage, mean dose to the larynx while meeting other planning requirement in RTOG protocol of 0225. Results: The average doses to 95% (D95) of the pGTVs and pCTV were 67.10 ± 6.56 Gy, 70.65 ± 1.62 Gy, 72.74 ± 1.76 Gy and 55.21 ± 3.41 Gy, 57.17 ± 1.51 Gy, 59.92 ± 1.01 Gy for SF, SEF, and EF‐IMRT plans, respectively. The tumordose coverage in SF IMRT plans was the worst among three methods. Accordingly, the average mean doses to the larynx were 29.25 ± 5.61 Gy, 29.41 ± 2.99 Gy, 41.87 ± 10.61 Gy, respectively. The mean dose to the larynx in EF‐IMRT plans were the highest among the three methods. Conclusions: The selective extended field IMRT provides adequate tumordose coverage and protects the larynx with the similar mean dose as the SF method. Research is supported by Siemens Corporation.
Modeling albuminuria in type 2 diabetes: a second look.

T he measurement of albumin excretion is recommended as an annual test for all patients with diabetes. By measuring albumin excretion, we hope to be able to predict which patients are at risk for developing diabetic nephropathy and end-stage renal disease, as well as to determine which patients are at highest risk for cardiovascular disease. Those with normal albumin excretion are asked to repeat the screening test annually, whereas those with elevated levels of albumin excretion are asked to repeat such measures more frequently because of the high intraindividual variability associated with the measurement. Those with elevated albumin excretion are recommended to receive drug therapy directed at reducing the risk of progressive kidney disease and cardiovascular events. Initial measurements of urinary protein were limited to quantification of total protein on a 24-hour urine specimen or dipstick determinations from a spot urine. When the measurement was more refined to albumin,
The short-term effects of electrosurgical ablation on proinflammatory mediator production by intervertebral disc cells in tissue culture

Abstract Background context Percutaneous discectomy can be performed by a variety of methods. One method, electrosurgical ablation, has been shown in a chronic animal model to alter the expression of inflammatory cytokines in degenerated discs. Purpose To determine whether electrosurgical ablation has an acute direct effect on proinflammatory mediator production by disc cells. Study design A short-term in vitro study using normal and interleukin (IL)-1α stimulated porcine disc cells cultured in alginate gel to evaluate the biochemical effects of electrosurgical ablation. Methods Porcine annulus and nucleus cells were embedded into alginate gels and cultured using control culture media or IL-1α–treated media for 6 days before ablation treatment. Treated gels were ablated by using a radiofrequency-based electrosurgical device for 5 seconds and cultured an additional 3 or 6 days. IL-1β, IL-6, IL-8, tumor necrosis factor α (TNF-α), prostaglandin E2 (PGE2), nitric oxide (NO), and heat shock protein-70 (Hsp70) levels in culture medium were measured. Levels were normalized to DNA and compared between ablated and shams. Results For normal annulus cells, there were no significant changes in cytokine levels between ablation and sham groups. For normal nucleus cells, ablation produced significantly greater levels of IL-8 at 3 days and 6 days, Hsp70 at 3 days but not 6 days, and NO at 6 days. PGE2 was also increased at 3 days and 6 days but not significantly. For IL-1–stimulated annulus cells, IL-6 and NO in the ablation group were decreased at 3 days relative to the control group. However, IL-6, IL-8, PGE2, and Hsp70 were significantly increased in the 6-day ablation group. For degenerated nucleus cells, IL-6, IL-8, and TNF-α were significantly decreased in the ablation group at both 3 days and 6 days. Ablation resulted in reduced PGE2 at 3 days but not 6 and reduced Hsp70 and NO at 6 days. Conclusions The results show that electrosurgical ablation has an acute direct effect on proinflammatory mediator production by disc cells. The effect produced depends on disc cell phenotype, the mediator, and time. These direct biologic effects may be a mechanism of pain relief after percutaneous discectomy using electrosurgical ablation. However, the measured responses are limited to the short-term (1 week), and the existence of a prolonged effect remains to be determined.
Isolation of Cryptococcus gattii from Oregon soil and tree bark, 2010–2011

Background In Oregon, human and animal infections by C. gattii were first identified in 2004. Cryptococcus gattii is considered to be an emerging non-zoonotic infection affecting animals and humans in Oregon. We report a longitudinal environmental isolation of C. gattii after an Oregon dog was diagnosed with the disease in 2009.
Life history adaptation along a latitudinal cline in the water strider Aquarius remigis (Heteroptera: Gerridae)

We addressed the general hypothesis that life history differences among eastern populations of the North American water strider, Aquarius remigis (Heteroptera: Gerridae), along a north-south gradient are manifestations of genetic differentiation due to natural selection. We raised offspring of two field-caught populations from each of three latitudes in a common laboratory environment at 20° C and two photoperiods. Nearly all Quebec (PQ) individuals (ca. 46° N) entered diapause to reproduce the following spring (univoltine life cycle), while intermediate proportions of New York (NY; ca. 43° N) and New Jersey (NJ; ca. 41° N) individuals reproduced directly, producing a second generation (bivoltine life cycle). PQ females were smaller, developed faster, and laid smaller eggs than NY and NJ individuals; NY and NJ populations differed little in these variables. NY females had longer life spans than either PQ or NJ females, but lower oviposition rates. Total reproductive output did not differ across latitudes. Photoperiod affected body length, development time, and reproductive pathway, resulting in a latitude by environmental interaction. PQ individuals reproduced directly under 15L : 9D (summer) conditions only, while the NY and NJ populations exhibited more direct reproduction under 13L : 11D (spring or fall) conditions. Some life history characters of the NY and NJ populations displayed the higher variability indicative of phenological transition zones. These results indicate local adaptation of populations to long-term climatic patterns. Water striders appear to adapt to longer seasons by extending development, growing larger, and breeding directly. Larger body size and extended or rapid development are associated with bivoltinism and increase in egg size, but not necessarily with higher fecundity or oviposition rate. The phenological transition zone appears to be unrelated to a transition zone a little further south established by allozyme data and morphology, as all populations studied here could be electrophoretically identified as northern "type".
Diversity and size changes in palaeonisciform fishes (Actinopterygii, Pisces) from the Pennsylvanian Mazon Creek fauna, Illinois, U.S.A.

ABSTRACT Seven palaeonisciform species can be recognized in the Middle Pennsylvanian Mazon Creek fauna of Illinois, U.S.A. Two of the five “Elonichthys” species with denticulated scales are new, “E.” wolffi, n.sp. and “E.” remotus, n.sp.; “E.” perpennatus Eastman, 1903, is a juvenile form and a synonym of “E.” hypsilepis Hay 1900. Two new species with smooth scales are placed in new genera: Illiniichthys cozarti, n.g. et sp., and Nozamichthys contorta n.g. et sp. “E.” peltigerus and “E.” hypsilepis are by far the most common palaeonisciforms in the Mazon Creek fauna and specimens of different stages of juvenile development occur. Most may be assigned to a species based on fin ray count (except caudal fin) because these numbers do not change with “growth.” Scales first appear on upper caudal lobe and/or along the lateral line. Head length and length of upper caudal lobe (except in “E.” hypsilepis) decrease relative to standard length during “growth.” Orbital length becomes shorter relative to head length i...
Early childhood healthy and obese weight status: potentially protective benefits of breastfeeding and delaying solid foods.

The aim of this study was to assess the relationship between breastfeeding and postponing introduction to solid food (SF) on children’s obesity and healthy weight status (WS), at 2 and 4 years. Drawing upon a nationally representative sample of children from the Early Childhood Longitudinal Study-Birth Cohort, we estimated the magnitude of the relationship between children’s WS and early feeding practices. Contingency tables and multinomial logistic regression were used to analyze obese and healthy WS for breastfed and never breastfed children and examine three timing categories for SF introduction. With both percentages and odds, breastfeeding and delaying introduction to SF until 4 months were associated with lower obesity rates and higher, healthy WS rates (typically 5–10 %). Analyses of feeding practice combinations revealed that when children were not breastfed, obesity odds decreased when SF introduction was postponed until 4 months. Obesity odds were further reduced when SF delay was combined with breastfeeding. Consistent increases in healthy WS were also observed. Benefits were stable across both follow-up periods. Breastfeeding and delaying complementary foods yielded consistently and substantially lower likelihood of obesity and greater probability of healthy WS. Health policies targeting early feeding practices represent promising interventions to decrease preschool obesity and promote healthy WS.
Use of expanded spectrum cephalosporins for the treatment of obstetrical and gynecological infections.

Abstract The antianaerobic cephalosporins, cefoxitin, ceftizoxime, cefotetan, and moxalactam, are compared in the treatment of obstetric/gynecologic infections associated with mixed aerobic and anaerobic pathogens. All of the antianaerobic cephalosporins have demonstrated similar efficacy in the treatment of mixed female genital tract infections. Thus, antibiotic selection requires a comparison of the antimicrobial activity, pharmacokinetics, adverse effects, and overall cost of therapy. All agents have excellent activity against the Gram-negative bacilli, and recent comparative data show that ceftizoxime is highly active against the Bacteroides sp. Dosing frequency and drug toxicity contribute to the overall cost of drug therapy. Cefoxitin is the only antianaerobic cephalosporin that cannot be dosed on a 12-hour basis. Ceftizoxime and cefoxitin, unlike moxalactam and cefotetan, do not contain the MTT group that has been associated with bleeding abnormalities. Substantial cost savings can be realized by using an antianaerobic cephalosporin administered every 12 hours. The experience at the Chicago Lying-in Hospital is presented.
N-glycosylation site tagging suggests a three transmembrane domain topology for the glutamate receptor GluR1

Summary We investigated the transmembrane topology of the glutamate receptor GluR1 by introducing N-glycosylation sites as reporter sites for an extracellular location of the respective site. Our data show that the N-terminus is extracellular, whereas the C-terminus is intracellular. Most importantly, we found only three transmembrane domains (designated TMD A, TMD B, and TMD C), which correspond to the previously proposed TMDs I, III, and IV, respectively. Contrary to earlier models, the putative channel-lining hydrophobic domain TMD II does not span the membrane, but either lies in close proximity to the intracellular face of the plasma membrane or loops into the membrane without traversing it. Furthermore, the region between TMDs III and IV, in previous models believed to be intracellular, is an entirely extracellular domain.
Contributions of local and regional sources of NOx to ozone concentrations in Southeast Texas

Abstract The Community Multi-scale Air Quality (CMAQ) model with a modified SAPRC-99 photochemical mechanism was used to investigate the contributions of local and upwind NO x sources to O 3 concentrations in Southeast Texas during the 2000 Texas Air Quality Study (TexAQS 2000) from August 25 to September 5, 2000. Contributions from eight different local NO x source types and eight different source regions to the 8-h average daytime O 3 concentrations from 1100 to 1800 CST (referred to as AD O 3 hereafter) are determined. Both diesel engines and highway gasoline vehicles account for 25 ppb of AD O 3 in the urban Houston area. NO x from natural gas combustion produces 35 ppb of AD O 3 in the industrial area of Houston. Contributions from industrial sources and coal combustion to AD O 3 have comparatively less broad spatial distribution with maximum values of 14 ppb and 20 ppb, respectively. Although the local sources are the most important sources, upwind sources have non-negligible influences (20–50%) on AD O 3 in the entire domain, with a maximum of 50 ppb in rural and coastal areas and 20 ppb in urban and industrial areas. To probe the origins of upwind sources contributions, NO x emissions in the entire eastern United States are divided into eight different regions and their contributions to O 3 concentrations in the Houston–Galveston–Brazoria (HGB) and Beaumont–Port Arthur (BPA) areas are determined. Among the various NO x source regions resolved in this study, other Texas counties near the HGB and BPA areas and southeastern states are the most important non-local sources of O 3 . Under favorable transport conditions, emissions from neighbor states and northeastern states could also contribute to non-negligible O 3 concentrations (7–15%) in the HGB and BPA areas. This indicates that in addition to reduce local emissions, regional NO x emission controls, especially from the neighbor counties and states, are also necessary to improve O 3 air quality in Southeast Texas.
Kinetic Study of Reactions of a Ketone with a Dialkylmagnesium Compound and with Organomagnesate Species1

The initial rate of formation of addition product from reactions of Np2Mg (Np = neopentyl) and phenyl tert-butyl ketone (1a) or o-methylphenyl tert-butyl ketone (1b) in benzene is proportional to [Np2Mg]0[1]1 when Np2Mg is in excess and to [Np2Mg]1[1]0 when ketone is excess. For either ketone, the rate is ca. 15-fold greater when ketone is in excess than when Np2Mg is in excess; regardless of which reagent is in excess, reactions of 1a are ca. 600-fold faster than reactions of 1b. 1H NMR absorptions of benzene-d6 solutions prepared with different Np2Mg/1b ratios indicate substantial formation of a 1:1 Np2Mg−1b complex, and when Np2Mg is in excess, some formation of a 2:1 complex. In THF as solvent, the initial rate of formation of addition product from Np2Mg and 1a is proportional to [Np2Mg]1[1a]1, and 1H NMR observations do not indicate Np2Mg−1b complexation. Formation of addition product from 1b and an organomagnesate solution prepared from KOMe and Np2Mg in benzene is 1−2 orders of magnitude faster tha...
Competent unit thickness variation in detachment folds in the Northeastern Brooks Range, Alaska: geometric analysis and a conceptual model

Detailed measurements of six map-scale detachment folds in the northeastern Brooks Range, Alaska, document significant variations in structural thickness of the competent Lisburne Limestone. Thickness variations occur mainly by parasitic folding and penetrative strain, and may be controlled by differences in mechanical stratigraphy, relative thicknesses of the competent and incompetent units, and structural relief of the underlying basement. The geometry of these detachment folds is not consistent with key assumptions of existing geometric and kinematic models, such as constant competent unit thickness or constant detachment depth. We propose a new model that allows both competent and incompetent unit thicknesses to vary throughout the fold. This model allows a more realistic geometric description of some natural detachment folds than previous models, but the number of variables makes unique reconstruction of specific fold geometries or kinematics difficult. Comparison of models with natural folds demonstrates that significant error can result if shortening estimates are based on models that incorrectly assume constant competent unit thickness or constant detachment depth. Use of surveying techniques to quantify map-scale fold geometry can provide better reconstructions of fold geometry, better shortening estimates, and information to constrain kinematic reconstructions.
Cultural constraints on professionalization: the case of nursing in India.

The development of professionalsim among any group of persons depends on the organizations success in insulating itself from or relating itself to its social context in order to retain a free hand in setting standards and policies. Both structural (i.e. training and professional organization aspects) and attitudinal (i.e. attitudes of the practitioners toward their work and attitudes of the community toward the work of the practitioners) attributes are important in the professionalization of any group. Nursing personnel have not succeeded in professionalization due to a number of cultural constraints. Planners for health services in India have been hindered in their attempts to professionalize medical personnel because the supply of trained personnel is so limited and because these trained personnel are largely concentrated in urban areas leaving the rural areas to the care of traditional health personnel. Traditional midwives are included in this number. Nursing personnel suffer from inadequate autonomy due to the socialization of girls within the community; they are encouraged to be dependent. The most serious obstacle to professionalization of nursing in India is the low status low pay and poor working conditions offered. All these conditions are culturally determined.
COMPRESSIVE BEHAVIOR OF MODERATELY THICK PLATES WITH PROGRESSIVE DAMAGE

An analytical methodology is presented to study the compressive behavior of moderately thick laminated plates under uniaxial compressive loads. Nonlinear in-plane stress-strain relations for transverse and shear modulus are considered and two failure criteria are incorporated to represent the progressive damage of composite plate structures. The finite-element analysis package, ABAQUS, with an updated Lagrangian formulation and large displacement and small strain kinematic relations, is employed in this study. Numerical analyses are conducted to demonstrate the effect of material nonlinearity, thickness-to-length ratio, and stacking sequence on the compressive behavior. Comparisons between the maximum-strain failure criterion and Hashin's failure criterion are presented.
The sublabial transseptal approach to the pituitary gland

Abstract Pituitary surgery is best performed by combining the expertise of otolaryngology and neurosurgery. Proper preoperative assessment and attention to the details of surgical technique will result in avoiding potential life-threatening complications. The sublabial transseptal approach to the sella turcica provides an effective and safe approach to the pituitary gland. A comparison with the endoscopic approach is also presented.
Supervised pixel classification using a feature space derived from an artificial visual system

Image segmentation involves labelling pixels according to their membership in image regions. This requires the understanding of what a region is. Using supervised pixel classification, the paper investigates how groups of pixels labelled manually according to perceived image semantics map onto the feature space created by an Artificial Visual System. Multiscale structure of regions are investigated and it is shown that pixels form clusters based on their geometric roles in the image intensity function, not by image semantics. A tentative abstract definition of a 'region' is proposed based on this behavior.
Hydra: a service oriented architecture for scientific simulation integration

One of the current major challenges in scientific modeling and simulation, in particular in the infrastructure-analysis community, is the development of techniques for efficiently and automatically coupling disparate tools that exist in separate locations on different platforms, implemented in a variety of languages and designed to be standalone. Recent advances in web-based platforms for integrating systems such as service-oriented architecture (SOA) provide an opportunity to address these challenges in a systematic fashion. This paper describes Hydra, an integrating architecture for infrastructure modeling and simulation that defines geography-based schemas that, when used to wrap existing tools as web services, allow for seamless interoperability. While conducting new studies in Hydra, existing users of these tools increase their analysis capabilities by assessing how the simulation results of one tool impact the behavior of another tool and can automate existing ad hoc processes and work flows for highly complex scenarios.
Gaussian-3 and related methods for accurate thermochemistry.

In this paper, we present an overview of Gaussian-3 (G3) theory, a composite technique that employs a sequence of ab initio molecular orbital calculations to derive a total energy of a given molecular species. This method provides accurate energies of molecular systems for the calculation of enthalpies of formation, ionization potentials, electron affinities, proton affinities, etc. Also covered in this review are several variants of G3 theory including one based on scale factors (G3S) and an extended version (G3X) that uses improved geometries and larger Hartree-Fock basis sets. Finally, the G3/99 test set of accurate experimental data that is used for critical assessment is described. Overall, G3 theory has a mean absolute deviation from experiment of 1.07 kcal mol−1 for the G3/99 test set and G3S theory has a similar accuracy of 1.08 kcal mol−1. G3X theory is significantly more accurate with the mean absolute deviation from experiment decreasing from 1.07 kcal mol−1 (G3) to 0.95 kcal mol−1 (G3X). The scaled version of G3X theory shows a similar improvement.
VLSI circuit design using APL with fortran subroutines

Our group at IBM Yorktown Research has written a number of tool programs for VLSI design, all in APL. Several crucial algorithms were speeded up by recoding them in Fortran and Assembler Language. For example, the algorithm for complementation of a Boolean expression (which can sometimes have thousands of terms in dozens of variables) is 5 times faster in Fortran than the best APL code I could write. The linking mechanism used from APL to outside languages is the experimental AP403 from IBM Heidelberg, though other similar auxiliary processors exist (e.g. the IUP AP999). Thus, each language, Fortran and APL, is used to its best advantage: Fortran for raw speed, and APL for interactiveness and ease of coding.
Investigation of stresses in he orthogonal cutting of fiber-reinforced plastics

A photoelastic study was conducted to examine the stress fields in the cutting process of fiber-reinforced plastics (FRPs). Force measurements were made and used in the analysis of the stress fields. Machined surfaces of workpieces with fibers oriented away from the cutting direction showed that the fibers were machined by shearing and tensile fracture; and when fibers were inclined towards the cutting tool, the fibers failed by shearing and bending. In addition, fiber-matrix debonding was observed to be maximum for fibers oriented at 45 deg towards the tool's path. Fiber orientation was shown to have an influence on the machining forces and stresses.
Ammonia Metabolism and the Urea Cycle: Function and Clinical Implications

Disposal of waste products accumulated during metabolic processes is integral to the health of any living organism. Disposal of excess nitrogen and ammonia is no exception. Although nitrogen is essential for growth and maintenance in animals, an excess of some nitrogenous compounds can quickly lead to toxicity and death. Because of the correlation between ammonia accumulation and clinical disease, it is important for veterinary clinicians to understand the physiological mechanisms used to dispose of nitrogen and ammonia. Therefore, the purposes of this article are to review ammonia metabolism, the urea cycle, and the clinical implications of urea cycle dysfunction in diseases of companion animals.
The Interfacial Properties of ApoA-I and an Amphipathic α-Helix Consensus Peptide of Exchangeable Apolipoproteins at the Triolein/Water Interface

Apolipoprotein A-I (apoA-I) is the major protein in high density lipoprotein (HDL). During lipid metabolism, apoA-I moves among HDL and triacylglycerol-rich lipoproteins. The main structure and the major lipid binding motif of apoA-I is the amphipathic alpha-helix. To understand how apoA-I behaves at hydrophobic lipoprotein interfaces, the interfacial properties of apoA-I and an amphipathic alpha-helical consensus sequence peptide (CSP) were studied at the triolein/water (TO/W) interface. CSP ((PLAEELRARLRAQLEELRERLG)2-NH2) contains two 22-residue tandem repeat sequences that form amphipathic alpha-helices modeling the central part of apoA-I. ApoA-I or CSP added into the aqueous phase surrounding a triolein drop lowered the interfacial tension (gamma) of TO/W in a concentration- and time-dependent fashion. The gamma(TO/W) was lowered approximately 16 millinewtons (mN)/m by apoA-I at 1.4 x 10(-6) m and approximately 15 mN/m by CSP at 2.6 x 10(-6) m. At equilibrium gamma, both apoA-I and CSP desorbed from the interface when compressed and readsorbed when expanded. The maximum surface pressure CSP could withstand without being ejected (PiMAX) was 16 mN/m. The PiMAX) of apoA-I was only 14.8 mN/m, but re-adsorption kinetics suggested that only part of the apoA-I desorbed at Pi between 14.8 and 19 mN/m. However, above approximately 19 mN/m (PiOFF) the entire apoA-I molecule desorbed into the water. ApoA-I was more flexible at the TO/W interface than CSP and showed more elasticity at oscillation periods 4-128 s even at high compression, whereas CSP was elastic only at faster periods (4 and 8 s) and moderate compression. Flexibility and surface pressure-mediated desorption and re-adsorption of apoA-I probably provides lipoprotein stability during metabolic-remodeling reactions in plasma.
Total energy of the adatom and pyramidal-cluster models for Si(111)

The total energy is calculated for a Si(111)-(2\ifmmode\times\else\texttimes\fi{}2) adatom geometry with a local bonding topology which is similar to the models of Harrison and Binnig et al. for the structure of the Si(111)-(7\ifmmode\times\else\texttimes\fi{}7) surface. This 2\ifmmode\times\else\texttimes\fi{}2 model is found to be higher in energy than the Pandey chain geometry by about 0.2 eV/(surface atom). The energy of a 2\ifmmode\times\else\texttimes\fi{}2 pyramidal-cluster model is also calculated, and is found to be higher than the chain surface by about 0.9 eV/(surface atom). The activation energy for diffusion on the ideal surface is estimated.
Functional heterogeneity of transducin α subunits

The N-terminal glycine of transducin α subunits is acylated by lauroyl (C12:0), myristoyl (C14:0), (cis-Δ5)-tetradecaenoyl (C14:1) or (cis,cis-Δ5,Δ8)-tetradecadienoyl (C14:2) fatty acyl groups. We examined functional heterogeneity of transducin by sequentially eluting it from bleached outer segments using increasing concentrations of GTP then identifying the N-terminal acyl groups on the eluted α subunits. C14:2 acylated transducin eluted at low GTP concentrations followed by C12:0, C14:1 and C14:0 transducin at higher GTP concentrations. This suggests functional heterogeneity in the different forms of transducin α subunits.
Kinetic parameters for crystallization in DICOR® glass

Abstract The reaction kinetics of crystallization of tetrasilicic flourmica in DICOR® glass was followed non-isothermally by differential thermal analysis (DTA), and analysed using Johnson-Mehl-Avrami equation for determining the activation energy, reaction order, and the pre-exponential parameters. The DTA curves showed a single exothermic crystallization peak in the temperature range of 745–850°C, just above the glass transition temperature. The activation energy Ec, the reaction order n, and the pre-exponential factor v, of crystallization were computed to be 203 kJ mol−1, 3.4 ± 0.20, and 2.88 × 1011 s−1 respectively. These observations suggest that the crystallization of mica in DICOR® glass occurs by a cellular precipitation mechanism where the nucleation occurs only at the start of the transformation.
Nurses' attitudes toward caring for patients with acquired immunodeficiency syndrome

The purpose of this study was to examine nurses' attitudes toward caring for patients with acquired immunodeficiency syndrome (AIDS) and factors that might be related to these attitudes. One hundred thirty-eight (138) registered nurses responded to an anonymous mail survey. The survey instrument assessed the subjects' attitudes toward caring for AIDS patients along five dimensions: (1) fears and concerns relating to caring for AIDS patients, (2) attitudes toward health care utilization by AIDS patients, (3) attitudes toward caring for terminally ill patients, (4) attitudes toward homosexuality, and (5) attitudes of significant others toward AIDS patients. The data obtained were analyzed using frequency distributions, independent t tests, and analysis of variance. Results of this study indicated that educational background is not related to nurses' attitudes toward caring for patients with AIDS; however, nurses who have had experience caring for patients with AIDS have more positive attitudes towards health care utilization by AIDS patients ( P P