cssi/SciSciGPT-SciSciNet huggingface dataset:
Heller myotomy vs Heller myotomy plus Dor fundoplication: cost-utility analysis of a randomized trial.

The addition of a Dor antireflux procedure reduces the risk of pathologic gastroesophageal reflux (GER) by ninefold following laparoscopic Heller myotomy for achalasia. It is not clear, however, how these benefits compare with the increased cost of the fundoplication. The objective of this study was to estimate the cost-effectiveness of Heller myotomy plus Dor fundoplication compared with Heller alone in patients with achalasia. We conducted a cost–utility analysis using the Markov simulation model to examine the two treatment alternatives. The model estimated the total expected costs of each strategy over a 10-year time horizon. Data for the model were derived from our randomized clinical trial. The strategies were compared using the method of incremental cost-effectiveness analysis. The incidence of pathologic GER was 47.6% (10 of 21 patients) in the Heller group and 9.1% (2 of 22 patients) in the Heller plus Dor group using an intention-to-treat analysis (p = 0.005). Heller plus Dor was associated with a significant reduction in the risk of GERD (relative risk 0.11; 95% confidence interval 0.02–0.59; p = 0.01). The cost of surgery was significantly higher for Heller plus Dor than for Heller alone (mean difference $942; p = 0.04), secondary to a longer operating room time (mean difference 40 min; p = 0.01). At a time horizon of 10 years, when proton pump inhibitor (PPI) therapy costs are considered, the cost–utility analysis demonstrates that Heller plus Dor surgery is associated with a total cost of $6,861 per patient and a quality-adjusted life expectancy of 9.9 years, whereas Heller-alone surgery is associated with a cost of $9,541 per patient and a quality-adjusted life expectancy of 9.5 years. In achalasia patients, Heller myotomy plus Dor fundoplication is preferred to Heller alone because it is both more effective in preventing postoperative GERD and more cost-effective at a time horizon of 10 years.
Altered gene regulation and potential association with metabolic resistance development to imidacloprid in the tarnished plant bug, Lygus lineolaris.

BACKGROUND Chemical spray on cotton is almost an exclusive method for controlling tarnished plant bug (TPB), Lygus lineolaris. Frequent use of imidacloprid is a concern for neonicotinoid resistance in this key pest. Information of how and why TPB becomes less susceptible to imidacloprid is essential for effective monitoring and managing resistance. RESULTS Microarray analysis of 6688 genes in imidacloprid-selected TPB (Im1500FF) revealed 955 upregulated and 1277 downregulated (≥twofold) genes in Im1500FF, with 369 and 485 of them annotated. Five P450 and nine esterase genes were significantly upregulated, and only one esterase gene and no P450 genes were downregulated. Other upregulated genes include helicases, phosphodiesterases, ATPases and kinases. Pathway analyses identified 65 upregulated cDNAs that encode 51 different enzymes involved in 62 different pathways, including P450 and esterase genes for drug and xenobiotic metabolisms. Sixty-four downregulated cDNAs code only 17 enzymes that are associated with only 23 pathways mostly related to food digestion. CONCLUSIONS This study demonstrated a significant change in gene expression related to metabolic processes in imidacloprid-selected TPB, resulting in overexpression of P450 and esterase genes for potential excess detoxification and cross/multiple resistance development. The identification of these and other enzyme genes establishes a foundation to explore the complicity of potential imidacloprid resistance in TPB. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Boulder dislodgement and transport by solitary waves: Insights from three-dimensional numerical simulations

The analysis of boulder motion and dislodgement provides important insights into the physics of the causative processes, i.e., whether or not a boulder was moved during a storm or tsunami and the magnitude of the respective event. Previous studies were mainly based on simplified models and threshold considerations. We employ three-dimensional numerical simulation of the hydrodynamics coupled with rigid body dynamics to study boulder dislodgement and transport by solitary waves. We explore the effects of three important nondimensional parameters on the boulder transport problem, the Froude number Fr, the aspect ratio in logarithmic scale α, and the submergence factor, β. Our results indicate that boulder motion is complex, and small changes in one of the nondimensional parameters result in significantly different behavior during the transport process and the final resting place of boulders. More studies are needed to determine the role of boulders in tsunami and storm hazard assessments.
Federal Tax Policy and Small Business

Do entrepreneurs need tax reform? This chapter presents a critical evaluation of the desirability of tax incentives for small businesses. We discuss measurement issues in identifying entrepreneurs in publicly-available data and then describe recent trends in several measures gleaned from tax data. Entrepreneurial activity is on the rise as evidenced by a growing share of non-corporate entities among business tax returns. Small businesses represent a disproportional share of taxable profits when compared to their share of total business receipts. We then turn to a discussion of the current tax treatment of entrepreneurs, followed by a brief overview of recent economic research on entrepreneurial sensitivity to tax policies. Economic theory suggests that taxes can have ambiguous effects on transitions into or out of entrepreneurial activity, which leaves the determination of overall effects to empirical analysis. This leads us to a presentation of our recent analysis of a twelve-year panel of U.S. federal individual income tax returns to examine the effects of federal income and payroll taxes and state income taxes on entrepreneurial activity. Our focus in this new analysis is on the effects of tax rates on individual transitions into or out of some form of entrepreneurial activity.
Optical control on 2-element CPW active integrated antenna array with strong coupling

The authors report the design and experimental data of a prototype of an optically controlled uniplanar active integrated antenna array. The active antenna circuit consists of two negative-resistance oscillators with two slots. As the transmission line, the CPW (coplanar waveguide) is used to realize the uniplanar active antenna array. The tuning of operating frequencies was carried out by illumination. Measured antenna patterns are presented. An optical tuning range of 70 MHz around 8.8 GHz was obtained. >
A new look at the ichthyoses: disorders of lipid metabolism.

The following three articles constitute the symposium on neonatal and developmental dermatology that was presented at the May 1986 meeting of the Society for Investigative Dermatology under the joint sponsorship of the Society for Investigative Dermatology, Society for Pediatric Dermatology, and Society for Pediatric Research.
Biodegradable block copolymers as injectable drug-delivery systems

Polymers that display a physicochemical response to stimuli are widely explored as potential drug-delivery systems. Stimuli studied to date include chemical substances and changes in temperature, pH and electric field. Homopolymers or copolymers of N-isopropylacrylamide and poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (known as poloxamers) are typical examples of thermosensitive polymers, but their use in drug delivery is problematic because they are toxic and non-biodegradable. Biodegradable polymers used for drug delivery to date have mostly been in the form of injectable microspheres or implant systems, which require complicated fabrication processes using organic solvents. Such systems have the disadvantage that the use of organic solvents can cause denaturation when protein drugs are to be encapsulated. Furthermore, the solid form requires surgical insertion, which often results in tissue irritation and damage. Here we report the synthesis of a thermosensitive, biodegradable hydrogel consisting of blocks of poly(ethylene oxide) and poly(L-lactic acid). Aqueous solutions of these copolymers exhibit temperature-dependent reversible gel-sol transitions. The hydrogel can be loaded with bioactive molecules in an aqueous phase at an elevated temperature (around 45 degrees C), where they form a sol. In this form, the polymer is injectable. On subcutaneous injection and subsequent rapid cooling to body temperature, the loaded copolymer forms a gel that can act as a sustained-release matrix for drugs.
Proprotein-processing endoproteases PC6 and furin both activate hemagglutinin of virulent avian influenza viruses.

Abstract Among the proprotein-processing subtilisin-related endoproteases, furin has been a leading candidate for the enzyme that activates the hemagglutinin (HA) of virulent avian influenza viruses. In the present study, we examined the cleavage activity of two other recently isolated ubiquitous subtilisin-related proteases, PACE4 and PC6, using wild-type HA of A/turkey/Ireland/1378/83 (H5N8) and a series of its mutant HAs. Vaccinia virus-expressed wild-type HA was not cleaved in human colon adenocarcinoma LoVo cells, which lack active furin. This processing defect was corrected by the expression of furin and PC6 but not of PACE4 and a control wild-type vaccinia virus. PC6 showed a sequence specificity similar to that with the endogenous proteases in cultured cells. When LoVo cells were infected with a virulent avian virus, A/turkey/Ontario/7732/66 (H5N9), only noninfectious virions were produced because of the lack of HA cleavage. However, when the cells were coinfected with vaccinia virus that expressed either furin or PC6, the avian virus underwent multiple cycles of replication, indicating that both furin and PC6 specifically cleave the virulent virus HA at the authentic site. These data suggest that PC6, as well as furin, can activate virulent avian influenza viruses in vivo, implying the presence of multiple HA cleavage enzymes in animals.
Purification and Characterization of Ferredoxin-Nicotinamide Adenine Dinucleotide Phosphate Reductase from a Nitrogen-Fixing Bacterium

Evidence suggesting that Bacillus polymyxa has an active ferredoxin-NADP + reductase (EC 1.6.99.4) was obtained when NADPH was found to provide reducing power for the nitrogenase of this organism; direct evidence was provided when it was shown that B. polymyxa extracts could substitute for the native ferredoxin-NADP + reductase in the photochemical reduction of NADP + by blue-green algal particles. The ferredoxin-NADP + reductase was purified about 80-fold by a combination of high-speed centrifugation, ammonium sulfate fractionation, and chromatography on Sephadex G-100 and diethylaminoethyl-cellulose. The molecular weight was estimated by gel filtration to be 60,000. A small amount of the enzyme was further purified by polyacrylamide gel electrophoresis and shown to be a flavoprotein. The reductase was specific for NADPH in the ferredoxin-dependent reduction of cytochrome c and methyl viologen diaphorase reactions; furthermore, NADP + was the acceptor of preference when the electron donor was photoreduced ferredoxin. The reductase also has an irreversible NADPH-NAD + transhydrogenase (reduced-NADP:NAD oxidoreductase, EC 1.6.1.1) activity, the rate of which was proportional to the concentration of NAD ( K m = 5.0 × 10 −3 M). The reductase catalyzed electron transfer from NADPH not only to B. polymyxa ferredoxin but also to the ferredoxins of Clostridium pasteurianum, Azotobacter vinelandii , and spinach chloroplasts, although less effectively. Rubredoxin from Clostridium acidi-urici and azotoflavin from A. vinelandii also accept electrons from the B. polymyxa reductase. The pH optima for the various reactions catalyzed by the B. polymyxa ferredoxin-NADP reductase are similar to those of the chloroplast reductase. NAD and acetyl-coenzyme A, which obligatorily activate NADPH- and NADH-ferredoxin reductases, respectively, in Clostridium kluyveri , have no effect on B. polymyxa reductase.
Mature Larvae of Calliopsine Bees: Spinoliella, Callonychium, and Arhysosage Including Biological Notes, and a Larval Key to Calliopsine Genera (Hymenoptera: Apoidea: Andrenidae: Panurginae)

ABSTRACT The known mature larvae of andrenid genera Spinoliella, Callonychium, and Arhysosage are described and compared with one another and with those of other Calliopsini. On the basis of both larval and adult anatomy, these three genera represent a distinctive clade, the “Spinoliella clade.” The larvae are characterized by conspicuously enlarged and oddly shaped, paired dorsal tubercles on the pro- and mesothorax, while the paired dorsal tubercles of most other body segments are erect, elongate, and slender. All dorsal tubercles bear fine setae. The larvae were collected on field trips to South America over a 35 year period. Associated field notes are reported, treating information on nesting ecology, nest structure and dimensions, provisions, larval behavior, associated cleptoparasites, and mating behavior. Also presented is a preliminary taxonomic key to the genera of Calliopsini based on mature larvae.
Fuzzy classification of earth terrain covers using complex polarimetric SAR data

Abstract The conventional approach of terrain image classification that assigns a specific class for each pixel is inadequate, because the area covered by each pixel may embrace more than a single class. Fuzzy set theory which has been developed to deal with imprecise information can be incorporate in the analysis for a more appropriate solution to this problem. In the current state of imaging radar technology, polarimetric synthetic aperture radar (SAR) is unique in providing complete polarization information of ground covers for more effective classification than a single polarization radar. In this paper, we use the fuzzy c-means clustering algorithm for unsupervised segmentation of multi-look polarimetric SAR images. A statistical distance measure adopted in this algorithm is derived from the complex Wishart distribution of the complex covariance matrix. In classifying polarimetric SAR imagery, each terrain class is characterized by its own feature covariance matrix. The algorithm searches for cluster...
Diaryl Hydrazones as Multifunctional Inhibitors of Amyloid Self-Assembly

The design and application of an effective, new class of multifunctional small molecule inhibitors of amyloid self-assembly are described. Several compounds based on the diaryl hydrazone scaffold were designed. Forty-four substituted derivatives of this core structure were synthesized using a variety of benzaldehydes and phenylhydrazines and characterized. The inhibitor candidates were evaluated in multiple assays, including the inhibition of amyloid β (Aβ) fibrillogenesis and oligomer formation and the reverse processes, the disassembly of preformed fibrils and oligomers. Because the structure of the hydrazone-based inhibitors mimics the redox features of the antioxidant resveratrol, the radical scavenging effect of the compounds was evaluated by colorimetric assays against 2,2-diphenyl-1-picrylhydrazyl and superoxide radicals. The hydrazone scaffold was active in all of the different assays. The structure–activity relationship revealed that the substituents on the aromatic rings had a considerable effec...
Health insurers' medical necessity determinations for bariatric surgery.

Abstract Purpose This study explored how state managed-care patient protection laws affect health insurers' criteria for medical necessity, using bariatric surgery for weight reduction as a case in point. Methods Six states and three national insurers were selected for in-depth case studies to represent a range of market, demographic, and legal conditions. In each state, 10–12 qualitative interviews were conducted in 2002 with insurers, regulators, providers, and healthcare attorneys, for a total of 71 interview subjects. Results Denials of coverage for bariatric surgery are a frequent source of appeals to external review, and external reviewers frequently overturn these denials. However, few insurers feel pressured to approve most or all requests for coverage because external review decisions do not set binding precedents. Instead, insurers continue to assert their own criteria for medical necessity, relying on the insurance contract's general definition of medical necessity. Some insurers, however, specifically exclude all weight reduction surgery because of the difficulty of defending case-by-case denials on appeal. Conclusions Unlike most areas of medicine, in which health insurers have greatly scaled back their past efforts to scrutinize medical necessity, for bariatric surgery, many insurers continue to apply a more stringent standard for medical necessity than the one that independent practicing physicians use.
Intelligent photon states associated with the Holstein - Primakoff realization of the SU(1,1) Lie algebra

We investigate the single-mode intelligent states associated with the Holstein - Primakoff realization of the SU(1,1) Lie algebra. These states can be shown to contract, under certain conditions, to the ordinary coherent or squeezed states in the limit of large Bargman index. We show that these states can have oscillatory photocount distributions, sub-Poissonian statistics and squeezing.
Kinetics of reorientation of the induced anisotropy in amorphous Fe40Ni40B20

Abstract The kinetics of the reorientation of the induced anisotropy in stress free amorphous Fe 40 Ni 40 B 20 have been studied from 180 to 260°C and compared with the previous study on Fe 40 Ni 40 P 14 B 6 . The FeNiB alloy is considerably more stable, but it exhibits a continuous distribution of time constants and activation energies (0.7 – 1.7 eV) by contrast to the single value of 1.4 eV found for the FeNiPB alloy. These results suggest that the local atomic environments involved in directional ordering of the FeNiPB alloy are more uniform than in the FeNiB alloy. An alternative description of the results is presented based on the observation that the reorientation of the anisotropy closely follows the equation for second order kinetics.
Effect of Amantadine Hydrochloride on the Response of Human Lymphocytes to Phytohemagglutinin

Amantadine hydrochloride (Symmetrel), which is an antiviral agent marketed for the prevention of infection by influenza virus, inhibits the mitogenic response of human lymphocytes stimulated with phytohemagglutinin. The concentrations which effectively inhibited the response to phytohemagglutinin were similar to those which maximally inhibit virus replication. The drug inhibited the mitogenic response without affecting the ability of phytohemagglutinin to agglutinate leukocytes. The data suggest that phytohemagglutinin, amantadine, and certain lipid-containing RNA viruses take part in cell-membrane interactions of common nature.
Who should get HU? … And how?

Sickle cell anemia is a cruel and disheartening disease that can be ameliorated by treatment with hydroxyurea (HU). HU can also cause life-threatening marrow depression. It probably can cause leukemia and skin cancer in patients with myeloproliferative disease, and it may be embryotoxic, teratogenic
Observation of new atomic nitrogen laser transition at 9064 Å

Abstract A new atomic laser line at 9046 A has been observed in the afterglow of helium-nitrogen discharge.
Perceived burden in spouses of National Guard/Reserve service members deployed during Operations Enduring and Iraqi Freedom.

Abstract Spouses of combat veterans with posttraumatic stress disorder (PTSD) experience elevated psychological distress. Recent research indicates that spouses’ perceptions of burden may be one mechanism of such distress, but there are several gaps in this literature. No research has examined perceived burden in relation to symptoms other than PTSD or subclinical levels of psychological distress, and very little research has focused on characteristics of spouses that may be related to their perceptions of burden. The current study examined these variables in 130 spouses of reserve component troops deployed during Operations Enduring/Iraqi Freedom. Spouses’ burden was positively associated with symptoms of PTSD, depression, and anxiety in service members, regardless of clinical severity. Moreover, burden fully mediated the relation between each type of symptom and spouses’ own psychological distress. Furthermore, levels of burden were significantly related to spouses’ neuroticism, avoidant coping, and self-efficacy, but only avoidant coping remained a significant predictor of burden when accounting for service members’ distress. These results suggest that a broad range of service members’ symptoms are related to spouses’ burden and distress, and although individual characteristics of spouses may be related to their perceptions of burden, service members’ symptoms play a primary role.
The role of cattle in the volatile loss of nitrogen from a shortgrass steppe

The cycling and volatile loss of N derived from cattle urine at upland and lowland sites within the shortgrass steppe of eastern Colorado was studied, using15N-labelled urea as an N source. Losses of NH 0 3 were determined by direct measurement and by difference. Losses were higher from coarse (27% summer, 12% winter) than from fine textured (0–2%) soils. Immobilization and plant uptake of N accounted for significant amounts of added N. Extrapolating our plot measurements to a typical pasture, using spatially and temporally stratified urine deposition data, losses from upland sites were calculated to be 0.016 g N · m-2 · y-1, while losses from lowland sites were negligible. This resulted in an average loss of 0.011 g N · m-2 · y-1 for a pasture divided 70:30 between uplands and lowlands. The loss of urine N calculated assuming no spatial stratification would be sevenfold higher (0.076 g N · m-2 · y-1). Losses of NH 0 3 from urine, animal biomass removal, and NH2O loss totaled only 0.07 g N · m-2 · y-1 , or about 25% of wet deposition input. We calculated a potential loss of NH 0 3 from senescing vegetation of 0.26 g N · m-2 · y-1, an order of magnitude larger than all other losses combined.
Processes Determining Cloudwater Composition: Inferences from Field Measurements

This paper examines field measurements bearing upon potential mechanisms responsible for the composition of cloudwater. Mechanisms considered include: 1) nucleation scavenging of aerosol; 2) scavenging of soluble gases; and 3) reactive scavenging of less soluble gases. The efficiency of aerosol scavenging by nucleation has been examined by use of a variety of physical and chemical techniques. The data are consistent with essentially complete (> 90%) scavenging of both particles mass and sulphate by cloudwater. Similarly, comparisons of interstitial HNO3 and cloudwater nitrate concentrations are consistent with essentially complete scavenging of nitric acid by cloud droplets. Studies of reactive scavenging have focussed on the aqueous phase reactions of SO2 with H2O2 and O3. Measurements of O3 and SO2 concentrations in and around clouds suggests that the O3/SO2 reaction is slow with respect to cloud lifetimes, consistent with calculations using laboratory derived rate parameters and typical atmospheric conditions. In contrast, the H2O2/SO2 reaction appears to be rapid for representative atmospheric conditions. Cloudwater H2O2 concentrations observed in our measurements ranged from less than 0.1 µM to 100 µM; equivalent gas phase concentrations, evaluated from aqueous phase concentrations, cloud liquid water content, and H2O2 solubility typically ranged from less than 0.05 and 1 ppb during the summer, and less than 0.05 ppb during a winter study. A strong negative correlation between cloudwater H2O2 and interstitial SO2 concentrations has been found in the data consistent with the rapid and quantitative in-cloud reaction of SO2 with H2O2 in which either these species acts as the limiting reagent. Low level stratus clouds sampled during a winter study generally exhibited high concentrations of interstitial SO2 and very low concentrations of cloudwater H202, suggesting at most a small contribution from aqueous transformation of SO2 by this oxidant. No direct evidence for the in-cloud oxidation of either NO or NO2 to HNO3 has been found in field data.
An application of Pólya's theory of counting to an enumeration problem arising in quadratic form theory

Abstract In this paper we apply Polya's theory of counting to compute the number of isomorphism types of reduced Witt rings of fields with a fixed finite number of orderings. The problem is first transformed into a graph theoretical enumeration problem involving unlabeled rooted trees with certain numbers assigned to the vertices.
New Degradable Cationic Lipid-DNA Complexes for Gene Delivery

Cationic lipids (CLs) continue to attract attention as synthetic nucleic acid (NA) vectors, and are broadly used for gene transfection and silencing including applications in clinical trials. However, these complexes exhibit suboptimal gene expression due to inefficiencies in overcoming the cellular barriers to transfection (Ahmad et al., J. Gene Med. 2005, 7, 739). After entry of the CL-DNA complex into the cell, two major barriers are efficient dissociation of DNA from the complex and the cytotoxicity of CLs. To address both these issues, we have synthesized a novel series of multi¬valent lipids (CMVLs) with degradable disulfide bonds linking the positively charged headgroups of the CMVLs to their hydrophobic tails. The linker is designed to be cleaved in the reducing milieu of the cytoplasm thus facilitating CL-NA complex degradation, reducing cytotoxicity and improving NA release. X-ray scattering demonstrates that CMVLs form lamellar complexes with DNA, which degrade in reducing environments mimicking the cytoplasmic milieu. For lipids with highly charged headgroups such as CMVL5 (5+), X-ray diffraction under reducing conditions shows DNA condensed by the cleaved headgroup. No such condensation is observed for smaller headgroup charge, as in CMVL2 (2+). Most significantly, we observed an unexpectedly large reduction in cytotoxicity of degradable CMVL-vectors compared to vectors prepared from corresponding lipids without degradable bonds (MVLs). This is of particular importance for applications in gene silencing, where the delivery of short interfering RNAs (siRNAs) requires large CL/NA charge ratios. Correspondingly, the transfection efficiency of CMVL-DNA complexes remains high for high CL/DNA charge ratios. In summary, the much reduced cytotoxicity of these new degradable multivalent lipids and their propensity for DNA release in the cytoplasm open the way for the development of efficient non toxic CL-vectors of NAs. Funding provided by NIH GM-59288.
Polarization reversal in PLZT 8/65/35 under hydrostatic pressures

Abstract Polarization reversal under pulse field conditions has been measured for hot-pressed ceramic PLZT at the 8:6 5:3 5 composition. In contrast to earlier data from Masuda et al., peaked switching current pulses with a clear maximum current i max could be observed and switching times are much shorter. The behavior in the low-field region is well characterized by the relations i max ∝e −∝/E and t s ∝ e ∝/ E where ∝ is the so-called activation field. Plots of ∝ versus pressure show increasing a up to a pressure of 3 kbar followed by a decreasing trend. It is speculated that this change at 3 kbar corresponds to the β:α transition under pressure in this composition.
Protons Forge New Paths

Abstract Crystal structures of bacterial reaction center second-site revertants (Xu et al., 2004) show that proton transfer energetics and connectivity are both important when this membrane protein reforms a proton transfer pathway broken by site-directed mutation.
Effects of dietary aflatoxin and zinc on enzymes and other blood constituents in dairy calves.

Abstract Young male Holstein calves were fed diets containing 40 or 640ppm zinc with 0 or 5ppm aflatoxin for 3 wk. The aflatoxin mixture contained 80.5% B 1 and the calves consumed 143mg of B 1 over 3 wk. Plasma glutamic-oxaloacetic transaminase and alkaline phosphatase concentrations were increased substantially, and lactic dehydrogenase was reduced in aflatoxin-fed calves. Supplemental zinc partially counteracted the effect of aflatoxin on these enzymes. Hemoglobin, packed cell volume, and total solids in blood plasma were increased in aflatoxin-fed calves, but high dietary zinc had no effect on these blood constituents. Glucose in plasma was reduced in calves receiving aflatoxin. High dietary zinc was only partially effective in protecting against the reduced glucose effect for about 1wk. Total protein, albumin, globulin, ratio of albumin/globulin in blood plasma, and liver lipid were not affected by aflatoxin. Several enzymes and blood constituents are affected by alfatoxin in calves. The protection of zinc against aflatoxicosis appears to be no more than a partial effect.
Superconducting-to-normally conducting transitions in strip transmission line structures

A theoretical and experimental investigation of superconducting‐to‐normally conducting transitions in strip transmission line structures is presented. The theoretical analysis is based on a macroscopic model, which is the transmission line analog of the Pippard model. It is assumed that during the transition a superconducting‐normally conducting (S‐N) interface propagates along the transmission line structure. This situation is treated theoretically as a moving boundary value problem. The S‐N interface propagation velocity is determined explicitly in terms of the current that induces the transition, the operating temperature, and the superconductive penetration depth. Experimental results indicate that the model is useful for predicting the transition time of a strip transmission line structure.
Dose-Intensive Therapy for Small Cell Lung Cancer

Enhancement of dose and dose intensity increases tumor response and may enhance long-term progression-free survival in patients with small cell lung cancer. Several strategies are identified to intensify therapy safely: a traditional induction/intensification mode, in which high-dose therapy with hematopoietic stem cell support is used to treat patients responding to conventional-dose therapy; and multicycle dose-intensive approaches, in which higher-dose therapy is administered over multiple cycles at initiation of therapy. This paper reviews some of the recently completed and activated trials (particularly those developed at the Dana-Farber Cancer Institute) exploring these concepts.
Amino-terminally truncated Aβ peptide species are the main component of cotton wool plaques

Cotton wool plaques (CWPs) are round lesions that lack a central amyloid core. CWPs have been observed in individuals affected by early-onset familial Alzheimer disease (FAD) associated with mutations in the presenilin 1 (PSEN1) gene. Here we present the characterization of the amyloid-beta (Abeta) peptides deposited in the brain of an individual affected by FAD carrying the novel missense (V261I) mutation in the PSEN1 gene. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry was used to determine the Abeta peptide species present in the cerebral and cerebellar cortices, in leptomeningeal vessels, and in CWPs isolated by laser microdissection (LMD). Our results indicate that amino-terminally truncated Abeta peptide species ending at residues 42 and 43 are the main Abeta peptides deposited in brain parenchyma and LMD-CWPs in association with the PSEN1 V261I mutation. Full-length Abeta1-42 and Abeta1-43 peptide species were underrepresented. CWPs were not found to be associated with vessels and did not contain Abeta1-40 peptides, the main component of the vascular deposits. Although Abeta deposits were present mostly in the form of CWPs in the cerebral cortex and as diffuse deposits in the cerebellar cortex, a similar array of amino-terminally truncated Abeta peptide species was seen in both cases. The biochemical data support the concept that parenchymal and vascular amyloid deposits are associated with a different array of Abeta peptide species. The generation and parenchymal deposition of highly insoluble amino-terminally truncated Abeta peptides may play an important role in the pathogenesis of AD and must be taken into consideration in developing new diagnostic and therapeutic strategies.
Coal agloflotation and supercritical wet oxidation: Novel remediation techniques for ultra-cleaning of contaminated soils

Abstract Soil contaminated with toxic organic compounds is a serious environmental problem facing the global community. Over time, organic pollutants which are trapped in the soil matrix leach through inadequate holding facilities and migrate deep into the earth, finally making their way to ground water aquifers. Once contaminated, these aquifers carry the toxins through the ecological system, bringing them into the food chain. Current technologies aimed at remediation of contaminated sites are inadequate in that they are site specific and often require secondary remediation. Coal agloflotation and superecritical wet oxidation (SWO) are two methods of soil remediation which can be utilized successfully to decontaminate polycyclic aromatic hydrocarbon (PAH) contaminated soil. Soil samples obtained from industrial town gas sites, with a total PAH contamination ranging from 2 to 17 mass percent, were remediated to environmentally acceptable standards with an end result of clean soil and usable byproducts from the processes. Hydrocarbon removal efficiencies were better than 95 percent for agloflotation and 99 percent for wet oxidation. A description of the individual processes is given as well as pertinent data to show the success of these two processes as primary and/or secondary treatment for soil remediation. A comparison between both processes is also given.
Changing Children's Conceptions of Burning.

Relatively few studies have examined the effects of instruction on children 's understanding of burning. This study focused on three questions. (a) What are children's views of burning prior to and after instruction? (b) Do children 's views become more scientific, that is, more in accord with scientists' views, with instruction, and if so, how? (c) Are the changes in children's understanding of burning correlated to their ages? Data were collected before and afterfive hours of instruction in a Saturday Science Program, using both a short multiple choice test based on common misconceptionsfrom the literature and "interviews about events. " Children were divided into two classes according to their grade in school. A significant difference was found in children 's understanding before and after instruction on the multiple-choice test that was corroborated with interview data. Younger children (ages 8 to 11) made more significant gains than did the older children (ages 11 to 13%, with both groups reaching similar levels of understanding after instruction. Although notable gains were made in recognizing the needfor oxygen in burning and in distinguishing between decomposition and burning, interviews revealed thatfew children at any age could explain specifically what was happening on the phenomena level.
Crystallographic determination of the mode of binding of oligosaccharides to T4 bacteriophage lysozyme: Implications for the mechanism of catalysis

Abstract Phage lysozyme has catalytic activity similar to that of hen egg white lysozyme, but the amino acid sequences of the two enzymes are completely different. The binding to phage lysozyme of several saccharides including N-acetylglucosamine (GlcNAc), N-acetylmuramic acid (MurNAc) and (GlcNAc)3 have been determined crystallographically and shown to occupy the pronounced active site cleft. GlcNAc binds at a single location analogous to the C site of hen egg white lysozyme. MurNAc binds at the same site. (GlcNAc)3 clearly occupies sites B and C, but the binding in site A is ill-defined. Model building suggests that, with the enzyme in the conformation seen in the crystal structure, a saccharide in the normal chair configuration cannot be placed in site D without incurring unacceptable steric interference between sugar and protein. However, as with hen egg white lysozyme, the bad contacts can be avoided by assuming the saccharide to be in the sofa conformation. Also Asp20 in T4 lysozyme is located 3 A from carbon C(1) of saccharide D, and is in a position to stabilize the developing positive charge on a carbonium ion intermediate. Prior genetic evidence had indicated that Asp20 is critically important for catalysis. This suggests that in phage lysozyme catalysis is promoted by a combination of steric and electronic effects, acting in concert, The enzyme shape favors the binding in site D of a saccharide with the geometry of the transition state, while Asp20 stabilizes the positive charge on the oxocarbonium ion of this intermediate. Tn phage lysozyme, the identity of the proton donor is uncertain. In contrast to hen egg white lysozyme, where Glu35 is 3 A from the glycosidic DOE bond, and is in a non-polar environment, phage lysozyme has an ion pair, Glull … Arg145, 5 A away from the glycosidic oxygen. Possibly Glull undergoes a conformational adjustment in the presence of bound substrate, and acts as the proton donor. Alternatively, the proton might come from a bound water molecule.
Assessment of global TEC mapping using a three-dimensional electron density model

Abstract Dual-frequency transmissions from the Global Positioning System satellites can be used to measure and map ionospheric total electron content (TEC) on global scales. Using data exclusively from ground-based GPS networks, global ionosphere mapping has been successfully applied using either two- or three-dimensional techniques. Two-dimensional TEC maps retrieve a horizontally-varying distribution of total electron content, assuming a fixed vertical electron density profile. In three-dimensional mapping, both the horizontal and vertical distribution density are adjusted to fit the data. We describe a three-dimensional TEC mapping algorithm that uses three independent constant-density slabs stacked vertically to model the electron density, and compare with a more conventional two-dimensional approach using a single slab. One apparent benefit of the new method is reduction in a level error of the TEC maps, which decreased by 1.7 TECU using the three-dimensional retrieval on simulated data (1 TEC Unit corresponds to 10 16 electrons/m 2 ). Another benefit of the multilayer approach is improved slant TEC modeling. Using actual data from an equatorial site at Cocos Islands (96.8E, 12.2 S), three slab modeling improved estimates of slant TEC by a factor of 2 for elevation angles between 10 and 20° (9 versus 4.4 TECU, root-mean-square). However, the global structure of the vertical TEC retrievals we analyzed did not improve using three-dimensional modeling. This may be due to a critical approximation shared by both techniques that TEC persists unchanged at a given local time. This assumption is required to produce global maps from observations acquired from widely scattered ground receivers. Further improving the retrieval of global TEC structure with ground-based data probably requires improved dynamical models of TEC behavior. New data available from GPS receivers in low Earth orbit is also promising.
Effect of Thyroid Releasing Hormone on Bladder and Urethral Pressures

In order to explain the pathophysiology of urinary urgency frequency observed following the administration of thyroid releasing hormone (TRH) during thyroid function testing, simultaneous urethrocystometry was performed in six females before and after TRH administration, and in another five females before and after administration of normal saline (control group). Within a few minutes following TRH administration, a statistically significant and consistent drop in maximal urethral pressure and concomitant sensation of urinary urgency in the absence of significant changes in true detrusor pressure suggested the presence of a reflex neuronally mediated motor component to this sensory effect of urinary urgency. The absence of urethral and detrusor pressure changes in the control group reinforced the TRH-mediated origin of urinary urgency.
The literate-programming paradigm

Literate programming, a technique for coding software systems that promotes readability and comprehension, is examined in detail. The current literate-programming paradigm is reviewed by looking at two sample literate programs. A critique of literate programming as it is currently used is presented, and methods for enhancing the process are explored. A number of new facilities are proposed, and restrictions on current literate-programming practices are suggested. >
Adolescent girls' and boys' preferences for provider gender and confidentiality in their health care.

Abstract Purpose: To assess the influence of demographic variables and health risk status on adolescents' preferences and actual receipt of services regarding provider gender, sharing a physician with parents, and private examinations. Methods: Data from students participating in the Commonwealth Fund 1997 Survey of the Health of Adolescent Girls were analyzed. The weighted sample included 6748 students from grades 5-12. The influence of demographic variables and health risk status on preferences regarding physician gender, sharing a physician with parents, and parental presence during examinations and on actual physician gender, sharing a physician with parents, and receipt of confidential care was assessed for the 5067 students who indicated that they had a health check-up or physical examination within the past 2 years. Associations were examined using SAS to determine preliminary estimates of significance and correlation coefficients, and SUDAAN to generate proportions and Cochran Mantel-Haenszel Chi-squared values. A multiple logistic regression procedure in SUDAAN was used to assess interaction among demographic variables. Results: Gender, race/ethnicity, grade level, and risk status were associated with preferences regarding provider gender and sharing a physician with parents. 50% of girls preferred a female provider; 48% had no preference. 23% of boys preferred a male provider; 65% had no preference. Most adolescents had no preference regarding whether they shared a physician with parents. Gender, race/ethnicity, grade level, and risk status were associated with preference regarding parental presence during examinations. Most younger girls preferred to have a parent present; most younger boys had no preference. Most older girls and boys preferred private examinations. For actual care situation, most adolescents were cared for by male health providers and did not share a physician with parents. 57% of girls and 66% of boys spoke privately with their health provider. Girls who had a female physician were more likely to have private time than were girls receiving care from a male physician. Gender, grade level, and risk status were associated with having private time with a physician. Conclusions: Gender was a significant variable in adolescents' preferences regarding health care. Preferences were also influenced by race/ethnicity, grade level, and risk status. A substantial proportion of adolescents, including those involved in health risk activities, report not having private time with their health provider.
The impact of histamine research on clinical anesthesia and surgery

The best protection patients have against the effects of histamine release are vigilant and educated clinicians. Thus, clinicians who are aware that histamine release can occur with many anesthetic drugs, that the release can be manifest as significant cardiovascular changes, and that the cardiovascular sequelae of histamine release can be prevented or treated, represent an important force in reducing anesthesia morbidity.
Exciton levels in a magnetic field

Abstract A variational calculation for the first six levels of m =0 even parity states of hydrogenic system in a magnetic field is given. Our calculation, which bridges the gap between low field states and high field states, strongly supports the non-crossing rule and stands completely against either of the proposed conservation criteria for the connection of high field states to the low field states. Plots showing the evolution of the nodal surfaces of excited state wavefunctions with changing magnetic field are presented. The relevance of our results to the interpretation of experimental excition spectra in TlCl and TlBr and donor spectra in GaAs is pointed out.
An integrated electronic spark source for basic and analytical emission spectroscopy

Abstract Described is one of a family of new, electronically-controlled spark sources which routinely operate at repetition rates up to 10 kHz and show high spark positional stability (±0.1 mm) for specific site analytical sampling. The conventional “spark source” and “stand” are integrated into a compact, RFI-free, assembly. The instrumentation directly follows previous development of electronically-controlled spark sources which use passive elements for current waveshaping and a hydrogen thyraton/diode parallel network as a commutating switch.
Effects of fasting, medium glucose, and amino acid concentrations on prolactin and growth hormone release, in vitro, from the pituitary of the tilapia Oreochromis mossambicus.

Previous investigations have shown that the release of PRL and GH from the tilapia pituitary is directly sensitive to osmotic pressure and a variety of endocrine and neuroendocrine factors. The present studies were aimed at determining whether the spontaneous release of PRL and GH, in vitro, is: (1) sensitive to the nutritional status of the fish, and (2) responsive to variations in the d-glucose and total amino acid content of the incubation medium. In the first series of experiments, male fish (50 to 60 g) were divided into two groups. One group was fed twice daily for 2 weeks while the second received no food. A nearly homogeneous mass of PRL-secreting cells was dissected from the rostral pars distalis (RPD) and incubated for 18 to 20 hr in either hyposmotic (300 mOsmolal) or hyperosmotic (355 mOsmolal) medium. Similarly, a mass of GH-secreting cells was dissected from the proximal pars distalis (PPD) and incubated for 18 to 20 hr in isosmotic (320 mOsmolal) medium. Fasting was found to alter the total amount of PRL and GH in the culture well (tissue + medium) at the end of the incubations, decreasing PRL and increasing GH. Fasting was also found to both reduce spontaneous PRL release in vitro and suppress its stimulation by reduced osmotic pressure (P < 0.01). By contrast, fasting resulted in a substantial increase in spontaneous GH release from the PPD in vitro (P < 0.01). In the second series of experiments, GH release was found to increase as the d-glucose concentration of the medium decreased (P < 0.01), while prolactin release was unresponsive. The spontaneous release of both PRL and GH in vitro was inversely related to the quantity of essential amino acids (Eagle's minimum essential medium; MEM) added to the incubation medium (P < 0.01). These findings suggest that the activity and regulation of PRL and GH cells in the tilapia pituitary may be sensitive to the nutritional status of the fish. It would also appear that GH cells, but not PRL cells, may respond to changes in circulating d-glucose levels and that both may respond to variations in circulating amino acids. Additional studies will be required to determine whether the latter response is directed by specific amino acids.
Part viii: Coronary stenoses with low translesional gradient and abnormal coronary reserve: Physiologic results after angioplasty

Clinically active but angiographically moderate coronary stenoses present a difficult problem for intervention, especially when such lesions have a low translesional pressure gradient and impaired coronary reserve. Physiologic data suggest some lesions can be safely deferred, whereas others may benefit from immediate intervention.