cssi/SciSciGPT-SciSciNet huggingface dataset:
Hodgkin's disease with leptomeningeal involvement: Report of a case with long survival

A 30-year-old white man with Stage IV B Hodgkin's disease, mixed cellularity type, developed leptomeningeal involvement shortly after relapsing on nitrogen mustard, Oncovin (vincristine), procarbazine, and prednisone (MOPP), and while receiving Adriamycin (doxorubicin), bleomycin, Velban (vinblastine), and dacarbazine (ABVD). Whole brain irradiation and intrathecal methotrexate were successfully incorporated into his treatment program. The patient has now been in complete remission for more than 40 months. A review of this rare complication of Hodgkin's disease is presented.
Oncologic outcomes of robotic-assisted total mesorectal excision for the treatment of rectal cancer.

Objective To evaluate local recurrence and survival after robotic-assisted total mesorectal excision (RTME) for primary rectal cancer. Summary background data RTME is a novel approach for the treatment of rectal cancer and has been shown to be safe and effective. However, the oncologic results of this approach have not been reported in terms of local recurrence and survival rate. Methods Sixty-four consecutive rectal cancer patients with stage I-III disease treated between November 2004 and June 2008 were analyzed prospectively. Results All patients underwent RTME: 34 had colorectal anastomosis, 18 underwent coloanal anastomosis, and 12 received abdominoperineal resection. Operative mortality rate was 0%. The median operative time was 270 min and median blood loss was 200 mL. The conversion rate was 9.4%. Anastomotic leakage occurred in 4 of 52 (7.7%) patients with anastomosis. Median number of harvested lymph nodes was 14.5. Median distal margin of tumor was 3.4 cm. The circumferential resection margin was negative in all surgical specimens. No port-site recurrence occurred in any patient. Six patients developed recurrence: 2 combined local and distant, and 4 distal alone (mean follow-up of 20.2 months; range, 1.7-52.5). None of the patients developed isolated local recurrence. The mean time to local recurrence was 23 months. The 3-year overall and disease-free survival rates were 96.2% and 73.7%, respectively. Conclusions RTME can be carried out safely and effectively in terms of recurrence and survival rates. Further prospective randomized trials are necessary to better define the absolute benefits and limitations of robotic rectal surgery.
Pediatric major resuscitation--respiratory compromise as a criterion for mandatory surgeon presence.

Abstract Summary The American College of Surgeons Committee on Trauma has indicated that there are minimum criteria for a trauma surgeon to respond to a major resuscitation (MR) within 15 minutes. These criteria have been required for children without significant data to support their validity. Our hypothesis is that prehospital intubation/respiratory compromise (IRC) as a criterion to define an MR will be an accurate predictor. Methods The trauma registry of a level I trauma center was used for data collection of age, injury severity score (ISS), IRC, mortality, hospital days, intensive care unit (ICU) days, and emergency operations. χ 2 with Yates correction and Mann-Whitney rank-sum testing was used for statistical analysis expressed as mean ± SEM. Results One hundred eighteen patients were encoded as MR. Forty patients had prehospital IRC and 78 patients did not. There were statistically significant differences seen in ISS, ICU length of stay, and mortality ( P Conclusion Injured children with prehospital IRC are significantly more likely to die, have a higher ISS, and a longer ICU length of stay. Prehospital respiratory distress in injured children in our trauma system is a reasonable criterion to define an MR in children.
Present uses of chlorofluorocarbons and effects due to environmental regulations

The paper deals with the expected impact of the safety and environmental issues concerning the use of Chlorofluorocarbons and presents a status report on alternative compounds under development.
Education and Information for Practicing School Nurses: Which Technology-Supported Resources Meet Their Needs?

School nurses care for children with a variety of health-related conditions and they need information about managing these conditions, which is accessible, current, and useful. The goal of this literature review was to gather and synthesize information on technology-supported resources and to determine which met the educational needs of school nurses. Successful online educational programs were interactive and self-directed. The most common barriers were lack of time to find educational information, lack of knowledge about computers, technology, the Internet and specific programs, and lack of administrative support from school officials to use technology to access information and evidence for practice. Recommendations for successful use of technology to meet practicing school nurse's educational needs are offered.
Effects of high-field stressing on the channel frequency-response of MOSFETs

Abstract The frequency response of the MOSFET inverted channel is analyzed by a transmission-line model. In this model, the interface traps are included and the minority carriers are assumed to follow the surface-potential variation. The channel frequency-response is characterized by two time constants ( τ l and τ GC ). The conductance G l and capacitance C 1 calculated from the minority-carrier current in the channel is used to determine τ I and τ GC from a frequency scan. Theoretical C 1 ( V ) and G 1 ( V ) curves are calculated and are in good agreement with experiments. The effect of high electrical field stressing is shown to increase both τ I and τ GC and thereby enlarge the frequency dispersion of the MOSFET admittances in inversion. The degradation in the channel frequency-response is more severe at lower inversion biases, where the degradation of mobility and the increase of interface-trap concentration are both more significant. The maximum of the G 1 ( V ) curve is very sensitive to the mobility and interface-trap concentration and can be used to monitor the degradation of the MOSFET. The degradation of the channel response due to high-field stressing is shown to depend on the gate-oxide thickness.
Efficient control of a solar assisted ground-source heat pump system based on evaluation of building thermal load demand

In this paper, a solar assisted ground-source heat pump system is proposed to provide thermal comfort for buildings. In order to improve the efficiency of the designed solar assisted ground-source heat pump system, a control strategy based on the evaluation of building thermal load demand is proposed. The system operates in different modes to adapt to outdoor and indoor environmental changes. In every control step, this control approach evaluates the real-time thermal load demand and makes decision on the operation strategy for next time step accordingly. A simulation study of the system operation for building heating is carried out to evaluate the efficiency of the proposed system.
Characterizing Concentration Effects of Exogenous Abscisic Acid on Gas Exchange, Water Relations, and Growth of Muskmelon Seedlings during Water Stress and Rehydration

Excess transpiration relative to water uptake often causes water stress in transplanted vegetable seedlings. Abscisic acid (ABA) can limit transpirational water loss by inducing stomatal closure and inhibiting leaf expansion. We examined the concentration effect of exogenous ABA on growth and physiology of muskmelon (Cucumis melo L.) seedlings during water stress and rehydration. Plants were treated with seven concentrations of ABA (0, 0.24, 0.47, 0.95, 1.89, 3.78, and 7.57 mM) and subjected to 4-day water withholding. Application of ABA improved the maintenance of leaf water potential and relative water content, while reducing electrolyte leakage. These effects were linear or exponential to ABA concentration and maximized at 7.57 mM. Gas-exchange measurements provided evidence that such stress control is attributed to ABA-induced stomatal closure. First, net CO2 assimilation rate and stomatal conductance initially decreased with increasing ABA concentration by up to 95% and 70%, respectively. A follow-up study (£1.89 mM ABA) confirmed this result with or without water stress and further revealed a close positive correlation between intercellular CO2concentration and netCO2assimilationrate 1day after treatment(r 2 > 0.83). In contrast, ABA did not affect leaf elongation, indicating that stress alleviation was not mediated by leaf area adjustment. After 18 days of post-stress daily irrigation, dry matter accumulation showed a quadratic concentration- response, increasing up to 1.89 mM by 38% and 44% in shoot and roots, respectively, followed by 16% to 18% decreases at >1.89 mM ABA. These results suggest that excess levels of ABA delay post-stress growth, despite the positive effect on the maintenance of water status and membrane integrity. Another negative side effect was chlorosis, which accelerated linearly with increasing ABA concentration, although it was reversible upon re-watering. The optimal application rate of ABA should minimize these negative effects, while keeping plant water stress to an acceptable level.
Agonist-induced desensitization of a P2Y-purinergic receptor-regulated phospholipase C.

Abstract A guanine nucleotide-dependent P2Y-purinergic receptor-regulated phospholipase C activity of turkey erythrocyte membranes has been characterized in detail previously (Boyer, J. L., Downes, C. P., and Harden, T. K. (1989) J. Biol. Chem. 264, 884-890). The occurrence of agonist-induced desensitization of this receptor-regulated phospholipase C is now described. Preincubation of turkey erythrocytes with the P2Y-purinergic receptor agonist ADP beta S resulted in a marked loss of capacity of ADP beta S plus GTP to stimulate phospholipase C in membranes derived from these cells. The half-time of occurrence of desensitization was 0.5-2.0 min, and within 10 min responsiveness had reached a new quasi-steady state level representing 40-55% of control. Transfer of agonist-preincubated erythrocytes to agonist-free medium resulted in recovery of agonist plus GTP responsiveness of the membrane phospholipase C activity to control levels with a half-time of 10-20 min. The change in ADP beta S plus GTP responsiveness occurred as a loss of maximal effect with little or no change in the apparent affinity of agonist for stimulation of inositol phosphate production. Induction of desensitization occurred with an agonist-specificity that followed that expected of a P2Y-purinergic receptor. Neither the rate of activation nor the final phospholipase C activity attained in the presence of GTP gamma S alone was altered in membranes from cells preincubated with ADP beta S for 15 min. AlF-4-stimulated inositol phosphate production was also not modified in membranes from agonist-preincubated erythrocytes. In contrast, the capacity of ADP beta S to increase the rate of activation of phospholipase C by GTP gamma S was markedly reduced in membranes from agonist-preincubated cells. The amount of 3H-radioactivity in phosphoinositides, as well as the ratio of labeling among the phosphoinositides, was not altered by incubation of erythrocytes with a P2Y-purinergic receptor agonist. Taken together these data suggest that P2Y-purinergic receptor agonist-induced desensitization occurs as a consequence of a modification at the level of the receptor or at the level of receptor-guanine nucleotide regulatory protein (G-protein) coupling with no change occurring in the capacity of the G-protein to activate phospholipase C.
Research Spotlight: Modeling saturation overshoot in porous media

[1] Infiltration of water into soils or porous rocks often follows unpredictable, preferential flow paths, also known as fingers. These fingers are caused by a condition called saturation overshoot, where the water content in the finger tip is greater than the water content in the finger tail. Why this happens has puzzled researchers,as overshoot cannot occur in traditional models. DiCarlo et al. used modeling and experiments to bridge the pore-level and continuum-scale physics behind saturation overshoot. Their model predicts the types of soils and initial conditions that are susceptible to overshoot and preferential flow. (Water Resources Research, doi:10.1029/ 2010WR009879, 2011)
Concentration of polar MFGM lipids from buttermilk by microfiltration and supercritical fluid extraction

Buttermilk contains the milk fat globule membrane (MFGM), a material that possesses many complex lipids that function as nutritionally valuable molecules. Milk-derived sphingolipids and phospholipids affect numerous cell functions, including regulating growth and development, molecular transport systems, stress responses, cross membrane trafficking, and absorption processes. We developed a two-step method to produce buttermilk derivative ingredients containing increased concentrations of the polar MFGM lipids by microfiltration and supercritical fluid extraction (SFE). These processes offer environmentally benign alternatives to conventional lipid fractionation methods that rely on toxic solvents. Firstly, using a ceramic tubular membrane with 0.8-micron pore size, we evaluated the cross flow microfiltration system that maximally concentrated the polar MFGM lipids using a 2n factorial design; the experimental factors were buttermilk source (fresh, or reconstituted from powder) and temperature (50 degrees C, and 4 degrees C). Secondly, a SFE process using supercritical carbon dioxide removed exclusively nonpolar lipid material from the microfiltered buttermilk product. Lipid analysis showed that after SFE, the product contained a significantly reduced concentration of nonpolar lipids, and a significantly increased concentration of polar lipids derived from the MFGM. Particle size analysis revealed an impact of SFE on the product structure. The efficiency of the SFE system using the microfiltration-processed powder was compared much more favorably to using buttermilk powder.
Identification of Enterobacteriaceae by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using the VITEK MS system

This multicenter study evaluated the accuracy of matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry identifications from the VITEK MS system (bioMerieux, Marcy l'Etoile, France) for Enterobacteriaceae typically encountered in the clinical laboratory. Enterobacteriaceae isolates (n = 965) representing 17 genera and 40 species were analyzed on the VITEK MS system (database v2.0), in accordance with the manufacturer's instructions. Colony growth (≤72 h) was applied directly to the target slide. Matrix solution (α-cyano-4-hydroxycinnamic acid) was added and allowed to dry before mass spectrometry analysis. On the basis of the confidence level, the VITEK MS system provided a species, genus only, or no identification for each isolate. The accuracy of the mass spectrometric identification was compared to 16S rRNA gene sequencing performed at MIDI Labs (Newark, DE). Supplemental phenotypic testing was performed at bioMerieux when necessary. The VITEK MS result agreed with the reference method identification for 96.7% of the 965 isolates tested, with 83.8% correct to the species level and 12.8% limited to a genus-level identification. There was no identification for 1.7% of the isolates. The VITEK MS system misidentified 7 isolates (0.7 %) as different genera. Three Pantoea agglomerans isolates were misidentified as Enterobacter spp. and single isolates of Enterobacter cancerogenus, Escherichia hermannii, Hafnia alvei, and Raoultella ornithinolytica were misidentified as Klebsiella oxytoca, Citrobacter koseri, Obesumbacterium proteus, and Enterobacter aerogenes, respectively. Eight isolates (0.8 %) were misidentified as a different species in the correct genus. The VITEK MS system provides reliable mass spectrometric identifications for Enterobacteriaceae.
The 41 kyr world: Milankovitch's other unsolved mystery

[1] For most of the Northern Hemisphere Ice Ages, from ∼3.0 to 0.8 m.y., global ice volume varied predominantly at the 41,000 year period of Earth's orbital obliquity. However, summer (or summer caloric half year) insolation at high latitudes, which is widely believed to be the major influence on high-latitude climate and ice volume, is dominated by the 23,000 year precessional period. Thus the geologic record poses a challenge to our understanding of climate dynamics. Here we propose that variations in the insolation gradient between high and low latitudes control high-latitude climate and ice volume during the late Pliocene and early Pleistocene. The differential heating between high and low latitudes, driven by obliquity, controls the atmospheric meridional flux of heat, moisture, and latent energy, which may exert the dominant control on high-latitude climate on Milankovitch timescales. In the two-dimensional zonal energy balance models typically used to study the long-term evolution of climate, the meridional atmospheric moisture flux is usually kept fixed. The hypothesis that insolation gradients control the poleward energy fluxes, precipitation, and ice volume at high latitudes has never been directly examined within the context of an ice sheet model. In light of what we know about modern energy fluxes and their relative influence on high-latitude climate, this possibility should be examined.
Carotid Endarterectomy: A Saga of Clinical Science, Personalities, and Evolving Technology The Willis Lecture

Mr Chairman, members, and guests of this annual international meeting on stroke, sponsored by the Stroke Council of the American Heart Association, an organization to which I have devoted over 20 years of admiration and service, it is an honor and privilege to present the Willis Lecture for 1998. Sir Charles Willis published the Anatome of the Brain and Nerves over 300 years ago. Feindel edited an excellent compilation of Willis’ work and published his tercentenary edition, entitled Cerebri Anatome, in 1964 . 1 Willis’ publication was more than anatomy of the brain and nerves. It set forth a number of functional as well as anatomic descriptions of the brain and the cranial nerves. The most significant point of the work was the description of the functional anatomy of the cerebral circulation. Willis applied, for the first time, the knowledge of William Harvey’s brilliant discovery to the special problems of the blood supply to the brain. He gave the anatomic description of the arterial circle at the base of the brain. He recognized the significance of this unique vascular anastomosis. He supported his insight into the principle of collateral circulation to the brain by the intravascular injection of colored dyes and by ligation, in animals, of blood vessels supplying and draining the brain. Finally, he attempted to correlate the problems presented in his medical practice in light of these anatomic and experimental results often supported by autopsy observations. Clearly, he recognized that the carotid and vertebral arteries in the neck were the source of the blood supply to the brain and were integral to the cross-circulation described. It is, therefore, highly appropriate that we focus today on the most commonly performed arterial surgical procedure, carotid endarterectomy, and the circuitous road of critique and clinical study it has followed to become …
Real-time reverse transcription-polymerase chain reaction assays for the detection and differentiation of North American swine influenza viruses

Swine influenza is an acute respiratory disease of swine caused by type A influenza viruses. Before 1998, mainly ''classical'' H1N1 swine influenza viruses (SIVs) were isolated from swine in the United States. Since then, antigenically distinct reassortant H3 and H1 SIVs have been identified as causative agents of respiratory disease in pigs on US farms. Improvement in SIV diagnostics is needed in light of the recently observed rapid evolution of H1 and H3 SIVs and their zoonotic potential. To address this need, real-time reverse transcription-polymerase chain reaction (RT-PCR) assays for the detection of SIVs were developed. A highly sensitive matrix (M) gene-based RT-PCR assay that is able to detect both the H1 and H3 subtypes of SIVs, with a sensitivity per reaction of approximately 2 copies of in vitro-generated M-specific negative-sense RNA molecules and approximately 0.05 TCID50 in lung lavage of experimentally SIV-infected pigs, was established. This RT-PCR assay can be performed within a few hours and showed a sensitivity of 94% and a specificity of 85% when compared with virus isolation. In addition, H1-, H3-, N1-, and N2-specific primer and probe sets were designed for use in the differentiation of different SIV subtypes. The hemagglutinin (H)- and neuramin- idase (N)-specific primer and probe sets were less sensitive than the M-specific assay, although they were found to be specific for their respective viral genes and able to distinguish between their respective SIV subtypes.
Super-resolution reconstruction in frequency, image, and wavelet domains to reduce through-plane partial voluming in MRI

Purpose: To compare and evaluate the use of super-resolution reconstruction (SRR), in frequency, image, and wavelet domains, to reduce through-plane partial voluming effects in magnetic resonance imaging. Methods: The reconstruction of an isotropic high-resolution image from multiple thick-slice scans has been investigated through techniques in frequency, image, and wavelet domains. Experiments were carried out with thick-slice T2-weighted fast spin echo sequence on the Academic College of Radiology MRI phantom, where the reconstructed images were compared to a reference high-resolution scan using peak signal-to-noise ratio (PSNR), structural similarity image metric (SSIM), mutual information (MI), and the mean absolute error (MAE) of image intensity profiles. The application of super-resolution reconstruction was then examined in retrospective processing of clinical neuroimages of ten pediatric patients with tuberous sclerosis complex (TSC) to reduce through-plane partial voluming for improved 3D delineation and visualization of thin radial bands of white matter abnormalities. Results: Quantitative evaluation results show improvements in all evaluation metrics through super-resolution reconstruction in the frequency, image, and wavelet domains, with the highest values obtained from SRR in the image domain. The metric values for image-domain SRR versus the original axial, coronal, and sagittal images were PSNR = 32.26 vs 32.22, 32.16, 30.65; SSIM = 0.931 vsmore » 0.922, 0.924, 0.918; MI = 0.871 vs 0.842, 0.844, 0.831; and MAE = 5.38 vs 7.34, 7.06, 6.19. All similarity metrics showed high correlations with expert ranking of image resolution with MI showing the highest correlation at 0.943. Qualitative assessment of the neuroimages of ten TSC patients through in-plane and out-of-plane visualization of structures showed the extent of partial voluming effect in a real clinical scenario and its reduction using SRR. Blinded expert evaluation of image resolution in resampled out-of-plane views consistently showed the superiority of SRR compared to original axial and coronal image acquisitions. Conclusions: Thick-slice 2D T2-weighted MRI scans are part of many routine clinical protocols due to their high signal-to-noise ratio, but are often severely affected by through-plane partial voluming effects. This study shows that while radiologic assessment is performed in 2D on thick-slice scans, super-resolution MRI reconstruction techniques can be used to fuse those scans to generate a high-resolution image with reduced partial voluming for improved postacquisition processing. Qualitative and quantitative evaluation showed the efficacy of all SRR techniques with the best results obtained from SRR in the image domain. The limitations of SRR techniques are uncertainties in modeling the slice profile, density compensation, quantization in resampling, and uncompensated motion between scans.« less
On the design of MOS dynamic sense amplifiers

This paper is concerned with the optimal design of MOS dynamic sense amplifiers used in MOS dynamic RAM's. An analysis of the operation of MOS dynamic sense latches has been carried out and optimal control for the latches has been derived. A first-order analysis of the effects of parameter mismatches on the sensitivity of cross-coupled pairs is also presented.
Endothelin-Converting Enzymes and Related Metalloproteases in Alzheimer's Disease

The efficient clearance of amyloid-β (Aβ) is essential to modulate levels of the peptide in the brain and to prevent it from accumulating in senile plaques, a hallmark of Alzheimer's disease (AD) pathology.We and others have shown that failure in Aβ catabolism can produce elevations in Aβ concentration similar to those observed in familial forms of AD. Based on the available evidence, it remains plausible that in late-onset AD, disturbances in the activity of Aβ degrading enzymes could induce Aβ accumulation, and that this increase could result in AD pathology. The following review presents a historical perspective of the parallel discovery of three vasopeptidases (neprilysin and endothelin-converting enzymes-1 and -2) as important Aβ degrading enzymes. The recognition of the role of these vasopeptidases in Aβ degradation, beyond bringing to light a possible explanation of how cardiovascular risk factors may influence AD risk, highlights a possible risk of the use of inhibitors of these enzymes for other clinical indications such as hypertension. We will discuss in detail the experiments conducted to assess the impact of vasopeptidase deficiency (through pharmacological inhibition or genetic mutation) on Aβ accumulation, as well as the cooperative effect of multiple Aβ degrading enzymes to regulate the concentration of the peptide at multiple sites, both intracellular and extracellular, throughout the brain.
Vibration-induced droplet atomization heat transfer cell for high-heat flux applications

This paper describes a unique two-phase cooling method that includes a closed heat transfer cell, similar to a thermosyphon that can be used to cool microelectronic packages. The cooling method is based upon a Vibration-Induced Droplet Atomization, or VIDA, process that can generate small liquid droplets inside a closed cell and propel them onto a heated surface. The VIDA technique involves the violent break-up of a liquid film into a shower of droplets by vibrating a piezoelectric actuator and accelerating the liquid film at resonant conditions. The droplets continually coat the surface with a thin liquid film, which evaporates on the heated surface, and the vapor is condensed on the internal surfaces of the heat transfer cell as well as the liquid working fluid. The condensed liquid is returned via gravity to the piezoelectric actuator where it is again atomized. A VIDA heat transfer cell 50 mm in diameter and 20 mm thick was constructed. Test data described in this study include the heat transfer characteristics and cooling capabilities for a small-scale cell that is suitable for cooling a desktop microprocessor during the burn-in portion of the manufacturing process. The VIDA process produces droplets of relatively uniform diameter, and the droplets have sufficient momentum to reach the remotely located heated source. Heat fluxes as high as 200 W/cm/sup 2/ have been measured when a chilled water heat exchanger is used as the external heat removal device.
Use of polyglyconate suture in paediatric gastrointestinal anastomosis.

The perfect suture has been defined, but in certain circumstances some features are more important than others. In paediatric gastrointestinal surgery lack of tissue drag is of great importance. Because the life expectancy of most paediatric patients having gastrointestinal operations is measured in many decades, and the long-term effects of retained suture materials are relatively undocumented, absorbability is also of importance. A polyglyconate copolymer suture (Maxon, Davis & Geck, Gosport, UK) has undergone trial. It is a monofilament absorbable suture. It has a low coefficient of friction, very low tissue drag and is stronger (straight pull and knot strength) than corresponding gauges of braided synthetic absorbable sutures. It is slowly absorbed, its half life (in relation to strength) being 5 weeks and complete disappearance occurring in 6–7 months. The trial was prospective and randomized. All members of the Department of Surgery at the Children's Hospital, Camperdown participated. Sixty-five anastomoses were performed in 56 patients. All varieties of joins were performed (oesophageal, duodenal, small and large bowel, and biliary-enteric). There were no statistically significant differences in the result in terms of outcome and complications. Overall handling and tissue drag were assessed by the surgeon at the end of the operation on a visual analogue scale and analysis of these results showed no significant difference in overall handling, but significantly less tissue drag (unpaired t-test). It is concluded that Maxon is superior to other currently available sutures for paediatric gastrointestinal surgery.
A Conjoint Approach to Multipart Pricing

Abstract Multipart pricing is commonly used by service providers such as car rentals, prescription drug plans, health maintenance organizations, and wireless telephony. The general structure of these pricing schemes is a fixed access fee, which sometimes entitles users to a certain level of product use; a variable fee for additional use; and still another fee for add-on features that are priced individually and/or as bundles. The authors propose a method using conjoint analysis for multipart pricing. The method reflects the two-way dependence between prices and consumption and incorporates consumers' uncertainty about their use of a service. The proposed method estimates both choice probabilities and usage levels for each consumer as functions of the product features and the different price components. The authors then use these estimates to evaluate the expected revenues and profits of alternative plans and pricing schemes. They illustrate this method using data from a conjoint study of cell phone servic...
Calculation of the thermodynamic properties at elevated temperatures and pressures of saturated and aromatic high molecular weight solid and liquid hydrocarbons in kerogen, bitumen, petroleum, and other organic matter of biogeochemical interest

Abstract To supplement the relatively sparse set of calorimetric data available for the multitude of high molecular weight organic compounds of biogeochemical interest, group additivity algorithms have been developed to estimate heat capacity power function coefficients and the standard molal thermodynamic properties at 25°C and 1 bar of high molecular weight compounds in hydrocarbon source rocks and reservoirs, including crystalline and liquid isoprenoids, steroids, tricyclic diterpenoids, hopanoids, and polynuclear aromatic hydrocarbons. A total of ninety-six group contributions for each coefficient and property were generated from the thermodynamic properties of lower molecular weight reference species for which calorimetric data are available in the literature. These group contributions were then used to compute corresponding coefficients and properties for ∼360 representative solid and liquid high molecular weight compounds in kerogen, bitumen, and petroleum for which few or no experimental data are available. The coefficients and properties of these high molecular weight compounds are summarized in tables, together with those of the groups and reference species from which they were generated. The tabulated heat capacity power function coefficients and standard molal thermodynamic properties at 25°C and 1 bar include selected crystalline and liquid regular, irregular and highly branched isoprenoids, tricyclic diterpanes, 17α(H)- and 17β(H)-hopanes, 5α(H),14α(H)-, 5β(H),14α(H)-, 5α(H),14β(H)-, and 5β(H),14β(H)-steranes, double ether- and ester-bonded n -alkanes, and various polynuclear aromatic hydrocarbons, including methylated biphenyls, naphthalenes, phenanthrenes, anthracenes, pyrenes, and chrysenes. However, corresponding coefficients and properties for many more saturated and unsaturated high molecular weight hydrocarbons can be estimated from the equations of state group additivity algorithms. Calculations of this kind permit comprehensive thermodynamic description of the chemical evolution of organic matter with increasing depth in sedimentary basins.
Practical stabilization of integrator switched systems

In this paper, practical stabilization problems for integrator switched systems are studied. In such class of switched systems, no subsystem has an equilibrium. However, the system can still exhibit interesting behaviors around a given point under appropriate switching laws. Such behaviors are similar to those of a conventional stable system near an equilibrium. We introduce some practical stability notions to define such behaviors. In particular, a necessary and sufficient condition for practical stabilizability of such systems is given. Moreover, for practically stabilizable systems, we develop a minimum dwell time switching law, which can easily be implemented. Finally, as an application, we apply the switching law to a batch process example.
Spectrum and energy levels of triply ionized lanthanum (La iv)

The spectrum of La iv has been observed in a sliding spark discharge with the NBS 10.7-m normal incidence vacuum spectrograph and the NBS 10.7-m Eagle spectrograph in air. A total of 368 lines have been observed in the region from 300 to 5000 A. About 190 lines have been classified as transitions between 49 energy levels. All levels of the 5p6, 5p5 5d, 6s, 6d, and 7s configurations as well as half of the levels of the 5p5 4f configuration have been located. Because of the greatly contracted 4f orbital, the lowest excited configuration is 5p5 4f. All configurations have been theoretically interpreted. The energy parameters determined from least-squares fits to the observed levels are compared with Hartree-Fock calculations. Some new measurements for La iii are presented that confirm the 1967 results of Odasbasi.
Soil carbon stocks under present and future climate with specific reference to European ecoregions

World soils and terrestrial ecosystems have been a source of atmospheric abundance of CO2 ever since settled agriculture began about 10–13 millennia ago. The amount of CO2-C emitted into the atmosphere is estimated at 136 ± 55 Pg from terrestrial ecosystems, of which emission from world soils is estimated at 78 ± 12 Pg. Conversion of natural to agricultural ecosystems decreases soil organic carbon (SOC) pool by 30–50% over 50–100 years in temperate regions, and 50–75% over 20–50 years in tropical climates. The projected global warming, with estimated increase in mean annual temperature of 4–6°C by 2100, may have a profound impact on the total soil C pool and its dynamics. The SOC pool may increase due to increase in biomass production and accretion into the soil due to the so-called “CO2 fertilization effect”, which may also enhance production of the root biomass. Increase in weathering of silicates due to increase in temperature, and that of the formation of secondary carbonates due to increase in partial pressure of CO2 in soil air may also increase the total C pool. In contrast, however, SOC pool may decrease because of: (i) increase in rate of respiration and mineralization, (ii) increase in losses by soil erosion, and (iii) decrease in protective effects of stable aggregates which encapsulate organic matter. Furthermore, the relative increase in temperature projected to be more in arctic and boreal regions, will render Cryosols under permafrost from a net sink to a net source of CO2 if and when permafrost thaws. Thus, SOC pool of world soils may decrease with increase in mean global temperature. In contrast, the biotic pool may increase primarily because of the CO2 fertilization effect. The magnitude of CO2 fertilization effect may be constrained by lack of essential nutrients (e.g., N, P) and water. The potential of SOC sequestration in agricultural soils of Europe is 70–190 Tg C yr−1. This potential is realizable through adoption of recommended land use and management, and restoration of degraded soils and ecosystems including wetlands.
Armada: a parallel I/O framework for computational grids

High-performance computing increasingly occurs on “computational grids” composed of heterogeneous and geographically distributed systems of computers, networks, and storage devices that collectively act as a single “virtual” computer. One of the great challenges for this environment is to provide efficient access to data that is distributed across remote data servers in a grid. In this paper, we describe our solution, a framework we call armada. The framework allows applications and dataset providers to flexibly compose graphs of processing modules that describe the distribution, application interfaces, and processing required of the dataset before computation. The armada runtime system then restructures the graph, and places the processing modules at appropriate hosts to reduce network traffic. © 2002 Elsevier Science B.V. All rights reserved.
The role of mechanical forces on the patterning of the avian feather-bearing skin: A biomechanical analysis of the integumentary musculature in birds.

The integumentary musculature of birds consists of three distinct components. The smooth musculature comprises feather and apterial muscles, which form a continuous musculo-elastic layer within the dermis. The feather muscles, which consistently include at least erectors and depressors, interconnect contour feathers within pterylae (i.e., feather tracts) along gridlines that are oriented diagonally to the longitudinal and transverse axes of the body. The apterial muscles interconnect pterylae by attaching to the contour feathers along their peripheries. The striated musculature is composed of individual subcutaneous muscles, most of which attach to contour feathers along the caudal periphery of pterylae A new integrative functional analysis of the integumentary musculature proposes how apterial muscles stabilize the pterylae and modulate the tension of the musculo-elastic layer, and how subcutaneous muscles provide the initial stimulus for erector muscles being able to ruffle the contour feathers within pterylae. It also shows how the arrangement of the contour feathers and integumentary muscles reflects the stresses and strains that act on the avian skin. These mechanical forces are in effect not only in the adult, especially during flight, but may also be active during feather morphogenesis. The avian integument with its complex structural organization may, therefore, represent an excellent model for analyzing the nature of interactions between the environment and genetic material. The predictions of our model are testable, and our study demonstrates the relevance of integrated analyses of complex organs as mechanically coherent systems for evolutionary and developmental biology.
Pedunculopontine tegmental nucleus lesions impair probabilistic reversal learning by reducing sensitivity to positive reward feedback

Recent findings indicate that pedunculopontine tegmental nucleus (PPTg) neurons encode reward-related information that is context-dependent. This information is critical for behavioral flexibility when reward outcomes change signaling a shift in response patterns should occur. The present experiment investigated whether NMDA lesions of the PPTg affects the acquisition and/or reversal learning of a spatial discrimination using probabilistic reinforcement. Male Long-Evans rats received a bilateral infusion of NMDA (30nmoles/side) or saline into the PPTg. Subsequently, rats were tested in a spatial discrimination test using a probabilistic learning procedure. One spatial location was rewarded with an 80% probability and the other spatial location rewarded with a 20% probability. After reaching acquisition criterion of 10 consecutive correct trials, the spatial location - reward contingencies were reversed in the following test session. Bilateral and unilateral PPTg-lesioned rats acquired the spatial discrimination test comparable to that as sham controls. In contrast, bilateral PPTg lesions, but not unilateral PPTg lesions, impaired reversal learning. The reversal learning deficit occurred because of increased regressions to the previously 'correct' spatial location after initially selecting the new, 'correct' choice. PPTg lesions also reduced the frequency of win-stay behavior early in the reversal learning session, but did not modify the frequency of lose-shift behavior during reversal learning. The present results suggest that the PPTg contributes to behavioral flexibility under conditions in which outcomes are uncertain, e.g. probabilistic reinforcement, by facilitating sensitivity to positive reward outcomes that allows the reliable execution of a new choice pattern.
Prediction of the Structure of Nobilisitine A Using Computed NMR Chemical Shifts

1H and 13C NMR computed chemical shifts are determined for eight diastereomers of the originally proposed structure of nobilisitine A, which has recently been shown to be incorrect. On the basis of comparison of the computed chemical shifts with those reported experimentally, we predict that the true structure of nobilisitine A is likely the diastereomer shown here or its enantiomer.
Hydrogeological Impacts of Urbanization

Urbanization creates hydrogeologic changes of significance both at the local scale and at larger scales. Urbanization and urban sprawl are projected to increase in the coming century, which will alter the corresponding groundwater systems both physically and chemically. Changes include the covering of shallow subsurface systems, (generally) increasing recharge from leaky utility systems and irrigation return flow, dramatic changes to subsurface secondary porosity and permeability from utility systems and other construction, the effects of imported water resources, and groundwater and soil contamination from point and non-point sources, storm-water control systems, and both modern and legacy pollution from urban development. Understanding of these changes, their causes, and their effects is necessary to addressing the critical and growing environmental and water resource issues of urban areas in the coming century.
Chemical Exchange Saturation Transfer (CEST) as a Tool to Measure Ligand Flexibility of Chelating Chiral Di-N-heterocyclic Carbene Complexes

A series of eight [(diNHC)Rh(CO)2][OTf] complexes, 1′-R, 2′-R, and 3′-R (where diNHC = DEAM, trans-9,10-dihydro-9,10-ethanoanthracene-11,12-diylmethanediyl carbene, and DEA, trans-9,10-dihydro-9,10-ethanoanthracene-11,12-diyl carbene ligands; R = R-methylphenylmethane (R-CHMePh), diphenylmethane (diPh), benzyl (Bn), methyl (Me), isopropyl (iPr), and o-methylbenzyl (o-MeBn); carbene heterocycle = imidazol-2-ylidene, and benzimidazol-2-ylidene), are synthesized and characterized. The purpose for the synthesis of these complexes was to examine the relationship between carbene N-heterocycle, R-group substitution, and metallocycle ring size (DEAM = 9, DEA = 7 atom ring) on ligand flexibility. The complexes were examined by chemical exchange saturation transfer to measure the rate of conformational isomerization. The results indicate that flexibility is not significantly altered by choice of carbene heterocycle and R group. However, the constrained DEA diNHC derivative does not undergo conformational isomerization.
KNOWLEDGE, ATTITUDES, AND BEHAVIOR RELATED TO OBESITY AND DIETING IN MEXICAN AMERICANS AND ANGLOS: THE SAN ANTONIO HEART STUDY

An epidemiologic study was carried out on Mexican Americans and Anglos residing in two socioeconomically and culturally distinct target areas in San Antonio: a middle income, ethnically integrated area ("transitional") and an upper income, predominantly Anglo area ("suburbs"). Although suburbanite Mexican Americans were leaner than their lower income counterparts, they were still more overweight than suburbanite Anglos. Even after adjusting for these differences in relative weight, however, Mexican Americans were still more likely than Anglos to express the opinion that Americans are too concerned about losing weight. Expressed as a per cent of the maximum score, Mexican American women in the transitional neighborhood scored 77% on this attitude item compared with 60% for Angle women (p less than 0.0005). Comparable ethnic differences on this attitude item were found in men in the transitional neighborhood and in suburbanites of both sexes. In the transitional neighborhood Mexican American women scored lower than Anglo women on a "sugar avoidance" and a "dieting behavior" scale: 23% for Mexican Americans and 45% for Anglos (p less than 0.0005) on the "sugar avoidance" scale. Comparable ethnic differences on this scale were found for men in the transitional neighborhood and for both sexes on the "dieting behavior" scale. Although no ethnic differences on these behavioral scales were found in the more affluent suburbs, these results nevertheless have public health relevance because the majority of Mexican Americans in the United States are of low socioeconomic status.
Stduy on Perfornance of MIMO-OFDM

According to the problem that Space time coding can not be directly applied to a flat fading channel.The scheme of combining OFDM with MIMO was put forward.The model of OFDM-STBC system was established.Information was distributed to many carrierin OFDM system,the sub-carrier signal rate was reduced greatly,the symbol period was later than multipath extension,in order to weaken the effects of multipath propagation.And the system performancewas simulated by using Matlab software,the simulation results show that reliability promotion ofthe OFDM-STBC system was improved greatly than the traditional STBC system.
General Consideration for Validation of Impurity Limitation in Drug Development

Impurity limitation of drug is an important question in quality control.It has some complicated problems in making the organic impurity limitation.This paper introduces the validation method for organic impurity limitation based on the evaluation experience,and discussed the general requirement for different chemical and different development process.
Event Selection from Phone Posteriorgrams Using Matched Filters.

In this paper we address the issue of how to select a minimal set of phonetic events from a phone posteriorgram while minimizing the loss of information. We derive phone posteriorgrams from two sources, Gaussian mixture models and sparse multilayer perceptrons, and apply phone-specific matched filters to the posteriorgrams to yield a smaller set of phonetic events. We introduce a mutual information based performance measure to compare phonetic event selection techniques and demonstrate that events extracted using matched filters can reduce input data while significantly improving performance of an event-based keyword spotting system.