cssi/SciSciGPT-SciSciNet huggingface dataset:
Outcomes following Turnbull–Cutait abdominoperineal pull‐through compared with coloanal anastomosis

Background: The Turnbull–Cutait abdominoperineal pull-through procedure (T-C) is used as a last resort to avoid permanent diversion in patients with complex anorectal conditions. The aim was to evaluate short- and long-term outcomes after T-C. Methods: Patients undergoing T-C from 1996 to 2007 were reviewed retrospectively in terms of demographics, diagnosis, indications and postoperative complications. Patients were contacted to obtain functional outcomes using a standardized questionnaire. Functional outcomes were compared with those in a matched group of patients undergoing handsewn coloanal anastomosis (CAA) for rectal cancer. Results: Sixty-seven patients (40 men) underwent T-C. Postoperative complications included stricture in 11 patients (16 per cent), fistula in five (7 per cent), prolapse of the colon in five (7 per cent) and leak in two (3 per cent). Mean follow-up was 5·6 (s.d. 3·2) years. The operation failed in 17 patients (25 per cent). Among 44 patients (66 per cent) who completed questionnaires, faecal (P = 0·121) and urinary (P = 0·073) incontinence, and sexual function (P = 0·063) were comparable to those in patients who had CAA. Conclusion: T-C is an option for patients with complex anorectal conditions that might otherwise require permanent diversion. Functional outcomes are comparable to those of CAA. Copyright © 2009 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.
Modification of host cell membrane after herpes simplex virus infection

Hemadsorption of sensitized sheep erythrocytes by herpes simplex virus (HSV) infected HeLa cells occurs independently of virus multiplication. When hemadsorption of HSV infected HeLa and rabbit kidney (RK) cells was compared with erythro-phagocytosis by rabbit macrophages, both the HSV infected cell cultures and the uninfected rabbit macrophages behaved exactly the same. This hemadsorption could be inhibited in both cell systems with homologous anti-host serum, whereas anti-HSV serum only inhibited the hemadsorption in HSV infected HeLa and RK cells. Some anti-metabolic agents capable of inhibiting the erythro-phagocytosis in macrophages could also inhibit the herpesvirus-induced hemadsorption.
Assessing the Utility of Methods for Menopausal Transition Classification in a Population-Based Cohort: The CARDIA Study

Abstract Objectives Perimenopause significantly impacts women's health, but is under-researched due to challenges in assessing perimenopause status. Using CARDIA data, we compared the validity of six approaches for classifying perimenopause status in order to better understand the performance of classification techniques which can be applied to general cohort data. Specifically, we examined the validity of a self-reported question concerning changes in menstrual cycle length and two full prediction models using all available data concerning menstrual cycles as potential indicators of perimenopause. The validity of these three novel methods of perimenopause classification were compared to three previously established classification methods. Methods For each method, women were classified as pre- or peri-menopausal at Year 15 of follow-up (ages 32–46). Year 15 perimenopause status was then used to predict Year 20 post-menopausal status (yes/no) to estimate measures of validity and area under the curve. Results The validity of the methods varied greatly, with four having an area under the curve greater than 0.8. Conclusions When designing studies, researchers should collect the data required to construct a prediction model for classifying perimenopause status that includes age, smoking status, vasomotor symptoms, and cycle irregularities as predictors. The inclusion of additional data regarding menstrual cycles can be used to construct a full prediction model which may offer improved validity. Valid classification methods that use readily available data are needed to improve the scientific accuracy of research regarding perimenopause, promote research on this topic, and inform clinical practices.
Performance of the Copper T-380A intrauterine device in breastfeeding women.

The effect of breastfeeding on performance of the TCu-380A IUD was evaluated using data derived from multicenter clinical trials. Insertion events for breastfeeding women (N = 559) and non-breastfeeding women (N = 590) were compared as well as discontinuations of IUD use through six months following insertion. Results indicate that breastfeeding women inserted with a TCu-380A are more likely than non-breastfeeding women to have a smooth, pain-free insertion, few postinsertion bleeding and pain problems, and a high rate of continuation of IUD use. There were no uterine perforations reported from either group of women.
Validation of Fatex - A Quick Diet Assessment Tool

Abstract LEARNING OUTCOME: To examine the validation of a diet assessment tool used to quickly determine the saturated fat and cholesterol content of a patient's diet from 3-day food records. FATEX (Fat Exchange System) was developed to assist a nutrition counselor to quickly calculate fat and cholesterol components of a patient's diet using a spreadsheet computer program. Utilizing an expanded food group system similar to diabetic exchanges, the counselor examines food records to determine the number of servings a patient has consumed from each food group and enters the information into the spreadsheet program. A printout of nutrient information for calories (CAL); grams of total fat (FAT); grams of saturated fat (SFA); and mg. of dietary cholesterol (CHOL) can be obtained, allowing comparison to Step 1-National Cholesterol Education Program (NCEP) diet guidelines. FATEX was validated for these four nutrients against the Minnesota Nutrition Data System (NDS), version 2.4 with 67 patients who received a Step 1 NCEP diet instruction from a registered dietitian (RD). Patients were asked to keep a 3-day food record and return it at their next visit. Records were reviewed with the patient by an RD and analyzed using both systems. CAL, FAT, SFA and CHOL values were compared for each of the 3 days (n=201) as well as the 3-day average (n=67) for each patient. A paired t-test comparison between these two systems validated the FATEX against NDS for CAL, SFA and CHOL. Results for the comparison of 1-day analysis were CAL (p
Biochemical and morphologic effects of ethanol on fetuses from normally ovulating and superovulated mice

To further our understanding about the teratogenicity of ethanol, we studied the changes produced by this compound in the incorporation of glucose 14C into several tissue fractions of 12-day mice fetuses and the morphologic alterations present at day 19 of gestation. Furthermore, to determine if the fetal toxicity of ethanol was modified by changes in the characteristics of the pregnancy, we performed similar biochemical and morphologic observations in fetuses from superovulated mice. Maternal ethanol administration caused biochemical alterations in the fetal tissues of both normally ovulating and superovulated mice, but it caused morphologic alterations predominantly in fetuses from superovulated animals. The prevalent morphologic alteration found in ethanol-treated animals was a hemorrhagic lesion dorsal to the lumbar or dorsal vertebrae. These results suggest that superovulation increases the susceptibility of the fetal mice tissues to the teratogenic effects of ethanol.
Increases in lung and brain water following experimental stroke: Effect of mannitol and hypertonic saline

Objective:Pulmonary edema is a serious condition following brain injury of diverse etiologies, including large hemispheric infarctions. We have previously shown that treatment with hypertonic saline attenuates cerebral edema associated with experimental ischemic stroke. In a well-characterized anima
Multi-agent autonomous pilot for motorcycles

In this paper we introduce a visualization application for a vehicle simulation with an automatic pilot. The application is written in OpenGL and includes a model of a vehicle (a motorcycle) based on the physical laws of motion, including kinematics, gravitation, and friction. The vehicle can be controlled by the user through keyboard and mouse commands, as well as by an automatic pilot. The latter is implemented as a multi-agent probabilistic scheme using perceptual data. Our intention is to simulate the behavior of a human driver on the road. The performance of the automatic pilot is compared with that of a human player.
Force relaxation in human skeletal muscle

A simple model of human skeletal muscle relaxation is presented. This model is used to challenge the Michaelis Menten approximation to the calcium pump, the degree of cooperativity between calcium binding and isometric force production, and the observability of cross bridge kinetics in whole muscle force relaxation.
Polycystic Ovarian Syndrome and the Metabolic Syndrome

Polycystic ovarian syndrome (PCOS), first described in 1937, was defined by specific ovarian histopathology and a constellation of signs and symptoms. Through the years, the etiology remained elusive, with heated debates focusing in turn on the ovary and then the pituitary as the causative agents. In the last several decades, it has become clear that insulin resistance makes up a very important component of this syndrome. With this knowledge, new therapies have emerged along with the realization that PCOS and the metabolic syndrome are closely related through their shared insulin resistance. In this review, the diagnosis, pathophysiology, and therapy of PCOS are discussed and upon this background, those areas held in common by PCOS and the metabolic syndrome are explored.
Amelioration of Polyuria by Amiloride in Patients Receiving Long-Term Lithium Therapy

Vasopressin-resistant diabetes insipidus is a common side effect of the treatment of affective disorders with lithium. We studied the effect of amiloride on lithium-induced polyuria in nine such patients receiving maintenance lithium therapy who had a vasopressin-resistant defect in urinary concentrating ability. After a mean (+/- S.E.) of 24 +/- 6 days of amiloride administration, the urine volume fell (from 4.7 +/- 0.6 to 3.1 +/- 0.3 liters per 24 hours; P less than 0.005), and the urine osmolality increased (from 228 +/- 35 to 331 +/- 34 mOsm per kilogram of H2O; P less than 0.001). The decrease in urine output was sustained during six months of observation in the absence of any significant change in plasma levels of lithium, potassium, or bicarbonate; urinary excretion of sodium or lithium; or creatinine clearance. Amiloride administration was also associated with a significant increase in urine osmolality (from 575 +/- 54 to 699 +/- 48 mOsm per kilogram of H2O; P less than 0.005) measured after fluid deprivation and the injection of exogenous vasopressin. We conclude that amiloride mitigates lithium-induced polyuria, at least partly, by blunting the inhibitory effect of lithium on water transport in the renal collecting tubule. Thus, amiloride may provide a specific therapy for polyuria in lithium-treated patients while obviating the need for potassium supplementation in the treatment of this kind of polyuria.
Zinc selenide synthesis in fiber draw

We demonstrate a high-throughput method for synthesizing zinc selenide (ZnSe) in situ during fiber drawing. Direct atomic-level compositional and structural analysis of the produced compound is performed, and a ZnSe-based in-fiber heterojunction device is achieved.
The role of phytosterols in host plant utilization by cactophilicDrosophila

The Cactus-Drosophila Model System of the Sonoran Desert consists of four endemic species ofDrosophila (D. mojavensis, D. nigrospiracula, D. mettleri andD. pachea) and five species of columnar cacti (agria, organpipe, saguaro, cardon and senita). Extensive collection records indicate that each cactus species has only one species ofDrosophila as the primary resident. The elimination of six of the twenty possible random combinations ofDrosophila species and cactus species can be attributed directly to phytosterols.Drosophila pachea has a strict requirement for Δ7-sterols such as 7-cholestenol and 7-campestenol. Since Δ7-sterols are found only in senita cactus,D. pachea cannot use agria, organpipe, saguaro or cardon as host plants. The lipid fractions of agria and organpipe are chemically similar and contain high concentrations of several 3β,6α-dihydroxysterols. Larval viability tests using chemical constitutents of organpipe cactus demonstrate that the sterol diols are toxic toD. nigrospiracula but not to the resident, species,D. mojavensis. Agria and organpipe are therefore unsuitable as host plants forD. nigrospiracula. These results suggest that phytosterols play a major role in determining host plant utilization by cactophilicDrosophila in the Sonoran Desert.
Effects of roadway visibility on steering errors while driving in blowing snow

Simulations of driving over a randomly-textured ground plane produce systematic steering errors when falling snow moves orthogonally to the driver's path (Dyre & Lew, 2005). Here, we examined whether these errors are mitigated by either high- or low-visibility roadways. Drivers viewed simulations of driving across a ground plane while snow moved at different speeds orthogonal to the initial direction of movement, which varies the angular distance between the focus of expansion (FOE) defined by the snow and the FOE defined by the environment. Drivers were instructed to steer such that they maintained a straight path relative to the ground. Three roadway visibility conditions were examined: no visible roadway, low-visibility roadway, and high-visibility roadway. Errors in steering and maintenance of lane position were related to the angular distance between the FOE for all roadway visibility conditions, although the magnitude of the errors lessened when low- and high-visibility roadways were present.
Effect of Mood and Eating Disorders on the Short-Term Outcome of Laparoscopic Roux-en-Y Gastric Bypass

Background We examined whether patients with a history of mood and eating disorders (MED) had less weight loss and poorer treatment compliance after laparoscopic Roux-en-Y gastric bypass (LRYGBP) than patients with a history of either mood (MD) or eating disorders (ED), or no history of mood or eating disorders (ND).
Transforming data into services: Delivering the next generation of user-oriented collections and services

For decades, the corporate sector has exploited technological advances to better market and deliver products and services to customers via the techniques of data mining. The technique was not widely used in libraries. However, with the current emphasis on evidence-based decision making, libraries are beginning to utilize their system- and user- generated data. Data mining usually involves a significant endeavor to extract embedded and potentially useful information from large undiscovered data sets (Mitra & Acharya, 2003; Hand, Mannila & Smyth, 2001; Frawley, Piatetsky-Shapiro, & Matheus 1992; Piatetsky-Shapiro & Frawley 1991). These data mining techniques are being used by librarians to improve both internal decision-making and external user services by extracting information from operational datasets of both bibliographic and user data. OCLC Research has taken advantage of the WorldCat database, which includes more than 95 million bibliographic records and 1.2 billion holdings records, as well as data provided by other major library systems and consortia to develop user-oriented collections and services (http://www.oclc.org/research/projects/mining/).
The importance of social context influences on new farm technology sustainability: community and sub-community characteristics in Jamaica

Abstract The research described in this article examines influences on long-term sustainability (LTS) of new technologies among Jamaican peanut farmers and finds that community context is most important. Several innovations introduced by an extension project were adopted to some extent, and some are still maintained. The research examines the influences on LTS of traditional adoption/diffusion characteristics of farmers, e.g. education, income, and age, and the community context in which farmers operate. To examine LTS—the dependent variables—the study focuses on labor-saving devices, e.g. shellers, sprayers, and strippers, which were introduced to increase productivity and lower labor costs. The study compares the impact of traditional adoption theory variables with community socioeconomic centrality, i.e. the totality of regional political, economic, and social access, as well as local organization membership, and social contact linkages (significant interaction with neighbors). Using regression analysis the results indicate that individual and farm characteristics make no difference, and local interpersonal contact networks make little difference, when local church membership (negatively related to LTS), and a community's socioeconomic centrality within the parish (positively related to LTS) are introduced as variables. Community ‘socioeconomic centrality’, measured by whether a community has access to regional bus service, is the strongest predictor of high levels of long-term sustainable adoption in the surrounding farms. This suggests that the chances of LTS are greatly enhanced if the right communities are chosen and, therefore, advance study of potential target communities seems essential.
Rh(2)(II)-catalyzed synthesis of carbazoles from biaryl azides.

An array of carbazoles (23 examples) can be synthesized from substituted biaryl azides at 60 °C using substoichiometric quantities of Rh2(O2CC3F7)4 or Rh2(O2CC7H15)4.
DELTA CONTRIBUTIONS TO THE PARITY-VIOLATING NUCLEAR-INTERACTION

A quark-model picture which incorporates SU(6${)}_{\mathit{w}}$ symmetry is utilized to calculate the weak \ensuremath{\Delta}-nucleon-meson and \ensuremath{\Delta}-\ensuremath{\Delta}-meson parity-violating vertices for \ensuremath{\pi}, \ensuremath{\rho}, and \ensuremath{\omega} mesons, thus extending previous work in the nucleon sector. The effective quark Hamiltonian is based upon the renormalization-group-corrected Weinberg-Salam model. The calculated parity-violating vertices are used to determine the coupling constants in an effective baryon Hamiltonian. We give ``best'' values as well as estimates of the ranges of uncertainty.
On the conservation of fast calcium wave speeds.

Calcium waves were first seen about 25 years ago as the giant, 10 micro m/s wave or tsunami which crosses the cytoplasm of an activating medaka fish egg [J Cell Biol 76 (1978) 448]. By 1991, reports of such waves with approximately 10 micro m/s velocities through diverse, activating eggs and with approximately 30 micro m/s velocities through diverse, fully active systems had been compiled to form a class of what are now called fast calcium waves [Proc Natl Acad Sci USA 88 (1991) 9883; Bioessays 21 (1999) 657]. This compilation is now updated to include organisms from algae and sponges up to blowflies, squid and men and organizational levels from mammalian brains and hearts as well as chick embryos down to muscle, nerve, epithelial, blood and cancer cells and even cell-free extracts. Plots of these data confirm the narrow, 2-3-fold ranges of fast wave speeds through activating eggs and 3-4-fold ones through fully active systems at a given temperature. This also indicate Q(10)'s of 2.7-fold per 10 degrees C for both activating eggs and for fully activated cells.Speeds through some ultraflat preparations which are a few-fold above the conserved range are attributed to stretch propagated calcium entry (SPCE) rather than calcium-induced calcium release (CICR).
Estrogen regulation of specific messinger RNA's in human breast cancer cells.

Summary Adaptation of a double isotope ratio method to the reticulocyte cell-free translation assay has revealed two estrogen-regulated mRNA's in the human breast cancer cell line MCF-7. These mRNA's code for proteins of 24,000 and 54,000 daltons as analyzed on SDS polyacrylamide gels. The 24K and 54K message levels increase 1.9 and 1.7 fold, respectively, following 6 days of estrogen treatment in cells whose growth has been inhibited by antiestrogen pretreatment. These results extend our previous observation that estradiol rescue of antiestrogen-blocked cells stimulates the synthesis of a 24,000 dalton protein in MCF-7 cytosols. Evidence for transcriptional control of this protein makes it an attractive probe for the study of hormone-regulated gene expression in human breast cancer.
Oscillatory behavior in the electrical resistivity of transition-metal superlattices

The electrical resistivity of Co/Ni and Cu/Ni superlattices exhibit resistivity oscillations as a function of superlattice period {Lambda}, while Ag/Pd does not. Moreover, the resistivity of Co/Ni superlattices shows quantum size effects and a resistivity enhancement with {Lambda}, as a function of total film thickness d. These results are consistent with a model which assumes d-electron localization in the superlattice structure. {copyright} {ital 1998} {ital The American Physical Society}
Blocking of electron donation by Mn(II) to YZ. following incubation of Mn-depleted photosystem II membranes with Fe(II) in the light

The donation of electrons by Mn(II) and Fe(II) to YZ• through the high-affinity (HAZ) site in Mn-depleted photosystem II (PSII) membranes has been studied by flash-probe fluorescence yield measurements. Mn(II) and Fe(II) donate electrons to YZ• with about the same efficiency, saturating this reaction at the same concentration (ca. 5 μM). However, following a short incubation of the membranes with 5 μM Fe(II), but not with Mn(II) in room light, added Mn(II) or Fe(II) can no longer be photooxidized by YZ•. This blocking effect is caused by specifically bound, photooxidized Fe [≥Fe(III)] and is accompanied by a delay in the fluorescence yield decay kinetics attributed to the slowing down of the charge recombination rate between Qa- and YZ•. Exogenously added Fe(III), on the other hand, does not donate electrons to YZ•, does not block the donation of electrons by added Mn(II) and Fe(II), and does not change the kinetics of the decay of the fluorescence yield. These results demonstrate that the light-dependent...
Studies of Congenital Heart Disease IV. Uncomplicated Pulmonic Stenosis

Congenital pulmonic stenosis is indicated by cardiac catheterization by the finding of a higher systolic pressure in the right ventricle than in the pulmonary artery. Eight cases of uncomplicated pulmonic stenosis are studied. The findings on history, physical examination, x-ray and fluoroscopy, and electrocardiogram have been analyzed and the variations in circulatory dynamics encountered in these individuals are described in detail.
Trade and Conflict: Proximity, Country Size, and Measures:

The effect of trade on military conflict is one of the most important questions in international relations. Liberals argue that trade brings peace, neo-realists and neo-Marxists reason that trade brings conflict, while classical realists contend that trade has no impact on conflict. This article investigates theoretically and empirically some of the most important issues that remain in this literature: the roles of geographical proximity, country size, the handling of the trade data, and the conceptualization of conflict. Employing a simultaneous equations model, we find that the claim that trade brings peace is not robust, but rather it is conflict that reduces trade.
Available and emerging treatments for Parkinson's disease: a review.

Parkinson’s disease is a commonly encountered neurodegenerative disorder primarily found in aged populations. A number of medications are available to control symptoms, although these are less effective in advanced disease. Deep brain stimulation provides a practicable alternative at this stage, although a minority of patients meet the strict criteria for surgery. Novel medications that provide enhanced symptomatic control remain in developmental demand. Both gene and cell-based therapies have shown promise in early clinical studies. A major unmet need is a treatment that slows or stops disease progression.
Modern mythic meaning: Blumenberg contra Nietzsche

Nothing surprised the promoters of the Enlightenment more, and left them standing more incredulously before the failure of what they thought were their ultimate exertions, than the survival of the contemptible old stories - the continuation of work on myth. (Blumenberg, 1985: 274)1
GPU-Based Acceleration for Interior Tomography

The compressive sensing (CS) theory shows that real signals can be exactly recovered from very few samplings. Inspired by the CS theory, the interior problem in computed tomography is proved uniquely solvable by minimizing the region-of-interest's total variation if the imaging object is piecewise constant or polynomial. This is called CS-based interior tomography. However, the CS-based algorithms require high computational cost due to their iterative nature. In this paper, a graphics processing unit (GPU)-based parallel computing technique is applied to accelerate the CS-based interior reconstruction for practical application in both fan-beam and cone-beam geometries. Our results show that the CS-based interior tomography is able to reconstruct excellent volumetric images with GPU acceleration in a few minutes.
Study of CO, NO, and H2 adsorption on model Pdα-Al2O3(0001) catalysts

Abstract We have examined the adsorption of CO, NO, and H 2 on α-Al 2 O 3 (0001)-supported, Pd particles using temperature-programmed desorption (TPD) in order to determine the effect of particle size on the desorption rates. For vapor deposition of Pd at 295 K, one obtains layer-by-layer growth of the Pd film. The film coalesces into a relatively uniform distribution of particles above ∼ 600K, as shown by TEM, with the particle sizes depending on the metal coverage. TPD curves for CO from all particle sizes are very similar to curves reported for bulk metals, with a main desorption feature at ∼ 490K and a second peak at ∼ 375K; however, the relative amount of CO desorbing from the low-temperature feature, assigned to linear CO, increases significantly for very small particles (∼ 1.6nm). For NO, more than half of the molecules desorb intact from large particles (5nm), with the remainder forming N 2 O and N 2 at ∼ 550K and leaving adsorbed oxygen. The fraction of molecules which dissociate during TPD increases significantly for small particles and only N 2 is observed as a product above 600 K. For H 2 at 120 K, desorption occurs in two regions on large particles, between 250 and 400 K for surface hydrogen and at ∼ 180K for hydrogen from the bulk. The only significant difference on small particles is the absence of the 180 K state. These results are discussed in terms of their implications for Pd particle-size effects in catalysis.
Low temperature removal of hydrogen sulfide from sour gas and its utilization for hydrogen and sulfur production

Abstract This investigation demonstrated the prospects for the development of chemical-electrochemical plants for the removal of hydrogen sulfide from sour gas and production of high quality hydrogen and sulfur at low temperatures. The anodic oxidation of sulfide ions, formed by scrubbing sour gas with sodium hydroxide and adjusting the pH of anolyte with more NaOH to a pH of nearly 14, produced polysulfide ions. In this cell the cathodic product was hydrogen, with the electrolyte in the cathode chamber being NaOH. The electrolyte in the anodic and the cathodic compartments was separated by an ion exchange membrane (Nafion). The sodium polysulfide was transferred to a separate chamber through which sour gas, at a high concentration (10–15 vol.%) of H2S, was passed. Crystalline sulfur was produced. The filtrate was mixed with the solution obtained by hydrogen sulfide scrubbing and returned to the electrolytic cell. Extremely pure hydrogen and sulfur were produced at a low cell voltage (Ecell = 1.0 V), and at a high current density (i = 300 mA cm−2).
Parathyroid hormone secretion in the absence of extracellular free Ca2+ and transmembrane Ca2+ influx

The involvement of extracellular Ca2+ and Ca2+ influx across the plasma membrane in parathyroid hormone (PTH) secretion was investigated in vitro using a new preparation of bovine parathyroid cells. Incubation of these cells in the presence of 25 μM or 2.5 μM free ambient Ca2+ induced a maximal rate of PTH secretion. Low free Ca2+ secretion is not associated with changes in membrane permeability, requires metabolic energy, and is reversible. The Ca2+ channel blocker D600 had no effect on either 45Ca-influx or PTH secretion in these cells. These results, showing that extracellular Ca2+ and Ca2+ influx across the plasma membrane are not required for PTH secretion by parathyroid cells, emphasize the differences in the cellular mechanisms underlying the secretion of PTH vs that of other secretory cells.
Function of Peroxidase and NADPH Cytochrome C Reductase During the Wolff-Chaikoff Effect

The effects of varying doses of stable iodide on thyroid peroxidase function and NADPH-cytochrome c reductase have been studied in rats. Wolff-Chaikoff effect was induced in vivo by injection of 250 or 500 μg of stable iodide, and several enzymatic activities of particulate fractions collected from the same thyroids were measured in vitro. There was no difference between the enzymatic activity (peroxidase and NADPH-cytochrome c reductase) of blocked and unblocked thyroid. Blocked thyroids showed increased 131I-PBI formation with NADPH in the same manner as unblocked thyroids. Iodide concentrations 10 times higher than those calculated to be present in the blocked thyroid (3 × 10-5M- 1.2 × 10-3M) were used in the in vitro reconstruction of the Wolff-Chaikoff effect with particulate fraction. Inhibition of iodination was not observed in vitro, even when low levels of tyrosine (10-5M) were used in the model system. Kinetic studies of the iodination reaction suggest that it follows a random mechanism, and sho...
A sterically-hindered tricyclic biimidazoline ligand which is also a precursor to a novel tetramethyl-cyclen

Abstract The synthesis of a tricyclic biimidazoline L featuring gem-dimethyl-substituted carbons α to the imino-nitrogens is described. A tris-chelate cadmium complex [CdL3](ClO4)2 has been prepared and fully characterized. Unlike the parent ligand's cadmium(II) tris-chelate complex, this [CdL3]2+ does not undergo facile exchange with free ligand in solution at ambient temperature. Ligand L is a convenient precursor to a novel bis(gem-dimethyl) derivative of cyclen: 2,2,9,9-tetramethyl-1,4,7,10-tetraazacyclododecane (2,2,9,9-Me4-Cyclen). Crystal structures of the L2·dithiooxamide adduct, the [CdL3](ClO4)2 complex, as well as 2,2,9,9-Me4-Cyclen have been determined.
Dose-related changes in the rate of cerebrospinal fluid formation and resistance to reabsorption of cerebrospinal fluid following administration of thiopental, midazolam, and etomidate in dogs.

The rate of cerebrospinal fluid (CSF) formation (Vf) and resistance to reabsorption of CSF (Ra) were determined in dogs at four doses of thiopental (6, 12, 18, and 24 mg.kg-1.h-1), midazolam (0.5, 1.0, 1.5, and 2.0 mg.kg-1.h-1), and etomidate (0.86, 1.72, 2.58, and 3.44 mg.kg-1.h-1). Results were compared within and between groups and to previously reported normal values for Vf (0.030-0.054 ml/min) and Ra (220-240 cmH2O.ml-1.min) in dogs. At the two lower doses of thiopental, midazolam, or etomidate Vf was not significantly different than previously reported normal values. At the two higher doses of each drug Vf was 0.019-0.024 ml/min, significantly reduced compared to Vf at the two lower doses of each drug. The pattern of Ra data was more varied. With thiopental Ra was elevated at the lowest dose, (354 +/- 17 cmH2O.ml-1.min, mean +/- SD) reduced at the highest dose (156 +/- 19 cmH2O.ml-1.min), and not significantly different than previously reported normal values at the two intermediate doses. With midazolam Ra was elevated at the lowest and highest doses (332 +/- 25 and 378 +/- 18 cmH2O.ml-1.min) and normal at the two intermediate doses. With etomidate Ra was normal at the three lower doses and reduced at the highest dose (187 +/- 13 cmH2O.ml-1.min). It is concluded that CSF volume may be increased and the CSF pressure at which CSF volume contracts may be increased by doses of thiopental or midazolam that increase Ra, but not increased by etomidate.
Synthesis and characterization of multi‐arm star‐branched polyisobutylenes

Multi-arm star-branched polyisobutylenes were synthesized by the “arm-first, core-last” method using the 2-chloro-2,4,4-trimethylpentane/pyridine/TiCl4 initiating system and the reactive core-forming comonomers 1,3-diisopropenylbenzene (DIPB) and divinylbenzene (DVB). Star formation was confirmed by RI and UV GPC and static light-scattering analyses. It was determined that DVB was significantly superior to DIPB. Using DVB, star polymers formed more rapidly and contained a much lower amount of residual PIB arms. Increasing the concentration of the reactive comonomer from 1 to 10 times the concentration of chain ends, [CE], increased the efficiency of the star-forming reaction substantially. Modest increases in the fraction of PIB arms incorporated into the star could be obtained by increasing the duration of the star-forming reaction. The timing of addition of the reactive comonomer to the PIB arms seems to be the process parameter most critical to the star development, since early addition at excessively low IB conversion hinders star formation by causing a copolymerization between IB and the core-forming comonomer. Late addition risks loss of a significant fraction of PIB chains due to spontaneous β-proton expulsion. A fully developed multi-arm star-branched PIB was synthesized by utilizing 10:1 [DVB]:[CE], 24 h star-forming reaction time, 14,000 g/mol target arm Mn, and addition of DVB at 99% IB conversion. The resultant star polymer contained only 4% unreacted PIB arms and possessed Mw = 345,000 g/mol by light scattering. The weight-average number of arms per star polymer was calculated to be 23. © 1996 John Wiley & Sons, Inc.
Multiple expressions of plume‐ridge interaction in the Galápagos: Volcanic lineaments and ridge jumps

[1] Anomalous volcanism and tectonics between near-ridge mantle plumes and mid-ocean ridges provide important insights into the mechanics of plume-lithosphere interaction. We present new observations and analysis of multibeam, side scan sonar, sub-bottom chirp, and total magnetic field data collected during the R/V Melville FLAMINGO cruise (MV1007; May–June, 2010) to the Northern Galapagos Volcanic Province (NGVP), the region between the Galapagos Archipelago and the Galapagos Spreading Center (GSC) on the Nazca Plate, and to the region east of the Galapagos Transform Fault (GTF) on the Cocos Plate. The NGVP exhibits pervasive off-axis volcanism related to the nearby Galapagos hot spot, which has dominated the tectonic evolution of the region. Observations indicate that ∼94% of the excess volcanism in our survey area occurs on the Nazca Plate in three volcanic lineaments. Identified faults in the NGVP are consistent with normal ridge spreading except for those within a ∼60 km wide swath of transform-oblique faults centered on the GTF. These transform-oblique faults are sub-parallel to the elongation direction of larger lineament volcanoes, suggesting that lineament formation is influenced by the lithospheric stress field. We evaluate current models for lineament formation using existing and new observations as well as numerical models of mantle upwelling and melting. The data support a model where the lithospheric stress field controls the location of volcanism along the lineaments while several processes likely supply melt to these eruptions. Synthetic magnetic models and an inversion for crustal magnetization are used to determine the tectonic history of the study area. Results are consistent with creation of the GTF by two southward ridge jumps, part of a series of jumps that have maintained a plume-ridge separation distance of 145 km to 215 km since ∼5 Ma.
Does Temporal Stratification Improve the Accuracy of Mark–Recapture Estimates of Smolt Production? A Case Study Based on the Conne River, Newfoundland

Abstract Based on an actual mark–recapture experiment with Atlantic salmon Salmo salar in the Conne River, a method was developed for simulating smolt migration when initial capture and tagging occur upstream and recapture occurs downstream at times that vary with the individual fish. The properties of Darroch's maximum-likelihood estimator of population size under time interval stratification were explored by Monte Carlo methods. In particular, the effects of population size and the width of the stratum interval on the bias and precision of the estimate of population size were examined under models of constant and variable probability of recapture. The viability of the asymptotic approximation of the variance of the estimate of population size was likewise examined. In addition to temporal strata, the case of no stratification was considered as well as a new estimator based on day-of-departure–day-of-recapture strata, from which daily estimates of the numbers leaving the upper site can be obtained. The s...
Integration Host Factor: Putting a Twist on Protein–DNA Recognition

Abstract Integration host factor (IHF) is a DNA–bending protein that recognizes its cognate sites through indirect readout. Previous studies have shown that binding of wild-type (WT)-IHF is disrupted by a T to A mutation at the center position of a conserved TTR motif in its binding site, and that substitution of βGlu44 with Ala prevented IHF from discriminating between A and T at this position. We have determined the crystal structures and relative binding affinities for all combinations of WT-IHF and IHF-βGlu44Ala bound to the WT and mutant DNAs. Comparison of these structures reveals that DNA twist plays a major role in DNA recognition by IHF, and that this geometric parameter is dependent on the dinucleotide step and not on the bound IHF variant.
Metabolism of pregnenolone by human breast cancer. Evidence for 17α-hydroxylase and 17,20-lyase

The metabolism of 7-(3)H-pregnenolone was studied in vitro using 16 human breast carcinomas. All mammary tumors transformed pregnenolone to progesterone. All estrogen receptor poor tumors and 4 out of 8 estrogen receptor rich tumors converted pregnenolone to 17-hydroxypregnenolone. Five estrogen receptor poor tumors showed the presence of 17,20-lyase as evidenced by formation of dehydroepiandrosterone and androstenedione. In two estrogen receptor poor tumors, conversions of pregnenolone to progesterone, 17-hydroxy pregnenolone, dehydroepiandrosterone, androstenedione and finally to estradiol was documented, providing a hypothetical pathway for steroid metabolism in human breast cancer. The conversion of pregnenolone to 17-hydroxypregnenolone was significantly less in receptor rich tumors and was totally absent in 4 receptor rich tumors with estrogen receptors of over 45 fmol/mg protein.
Maternal labelling of novel and familiar objects: implications for children's development of lexical constraints

Mothers' provision of names for novel and familiar toy animals was examined during play interactions with 20 infants observed at ages 0;10, 1;1, 1;5, and 1;9. Of particular interest were characteristics of mothers' speech which might bear on children's development of lexical principles or constraints. Analyses demonstrated that mothers facilitated their children's determination of reference and differentially adjusted their naming practices to novel, comprehended, and familiar animals. They virtually always named the whole object first. More important, the first mention of novel, but not comprehended or familiar animals involved both maternal naming and physical designation of the object 92% or more of the time. Thus, although a novel word's referent may be indeterminate logically, mothers specify it practically. These results support the position that maternal labelling practices may assist children in acquiring lexical principles and that lexical acquisition, perhaps even the vocabulary spurt, can proceed during natural conversational interactions before infants master lexical principles.
Digital simulation of discrete flow systems

The use of digital computers as simulation devices for analysis and synthesis of discrete flow systems is an increasingly important area of computer applications technology. Discrete flow systems are characterized by channeled movement of items according to basic patterns or constraints which are modified by events and elapsed time. In general, mathematical models are not developed for such systems in order that computer simulation be effected; it is more efficient to formulate the simulation flow chart directly from knowledge of the physical system. In this sense, and also in the programming techniques employed, simulation of discrete flow systems is accomplished by a different methodology than is commonly used in the simulation of engineering and scientific problems of the continuous flow type.Two discrete flow problems were programmed for a medium-speed digital computer (IBM 650). One of the models was based on a straightforward time-sequenced, grid-representation of the physical system, and the other, while also time sequenced, used an event-oriented representation of the system.
Differential payoff and locus of selectivity in a visual memory task

Two experiments were run to investigate the locus of selectivity in a visual memory task involving differential payoff for letters correctly recalled: Major variables consisted of value instructions given before or after the exposure of a display, the ratio of high to low value, and exposure duration. The results showed that Ss make more correct reports of higher value than of lesser value, whether value instructions are given before or after the display. Furthermore, overall performance and extent of selectivity increase with increasing exposure time, but more for the before than the after conditions of instruction. These results suggest that selectivity occurs both during perception and retention and during recall.
Ontology driven integration platform for clinical and translational research

Semantic Web technologies offer a promising framework for integration of disparate biomedical data. In this paper we present the semantic information integration platform under development at the Center for Clinical and Translational Sciences (CCTS) at the University of Texas Health Science Center at Houston (UTHSC-H) as part of our Clinical and Translational Science Award (CTSA) program. We utilize the Semantic Web technologies not only for integrating, repurposing and classification of multi-source clinical data, but also to construct a distributed environment for information sharing, and collaboration online. Service Oriented Architecture (SOA) is used to modularize and distribute reusable services in a dynamic and distributed environment. Components of the semantic solution and its overall architecture are described.
Temperature-modulated aflatoxin B1 hepatic disposition and formation and persistence of DNA adducts in rainbow trout.

Abstract Previous work showed that the incidence of chemically induced tumors in fish increased with environmental temperature. The present study assessed genotoxicity as a mechanism to explain such results. Rainbow trout (2 g) were acclimated to 10 or 18°C for 1 month and then immersed in 0.1 ppm [ 3 H]aflatoxin B 1 (AFB1) solutions for 30 min at their respective acclimation temperatures, or at 14°C. The total radioactivity in liver immediately after immersions was 50% higher for 18- than 10°C-acclimated and exposed fish. Conversely, adduction of [ 3 H]AFB1 to hepatic DNA of 10°C-acclimated fish was higher than that of 18°C-acclimated fish after exposure. A similar DNA adduction result was observed after [ 3 H]AFB1 immersion concentrations were varied to achieve similar hepatic [ 3 H]AFB1 equivalents. After acute shifts in temperature (10 to 14°C or 18 to 14°C), no differences were found in hepatic [ 3 H]AFB1 equivalents. However, adduction of [ 3 H]AFB1 to hepatic DNA was higher for 10- than for 18°C-acclimated fish 1 day after exposures at 14°C. This was probably explained by effects of temperature acclimation on the status of the membrane-bound cytochrome P-450 system, affecting its competition with a detoxifying cytosolic enzyme. After [ 3 H]AFB1 immersions at respective acclimation temperatures, or acute temperature shifts to 14°C, DNA adducts were less persistent in fish maintained for 21 days at 18°C than at 10°C. Our data demonstrated that temperature-modulated AFB1 genotoxicity occurred via three mechanisms: hepatic disposition and formation and persistence of DNA adducts.
Review of “Stereochemistry Workbook, 191 Problems and Solutions” by K.-H. Hellwich and C. D. Siebert

The late Edgar Heilbronner, one of the great physical and organic chemists of the 20th century, had a particularly effective lecture. He started it as follows: “You know pretty much everything I am going to say. So let us begin with the questions.” And up on the screen flashed the first question. The lecture continued in the same vein; Heilbronner’s carefully structured answers to just the right questions led to a fascinating seminar, and a learning experience. I thought of Edgar Heilbronner’s lecture as I read the Hellwich and Siebert “Stereochemistry Workbook.” In it are 191 graduated problems, along with succinct and clear solutions. One has to know a little stereochemical lore to begin with, for instance the priority rules of the CIP system. But otherwise everything is taught, in exemplary fashion, just through the progression of questions and answers. Complexities of naming coordination compounds, and dealing with chirality planes and axes are not avoided. The examples grow increasingly challenging. The success of this small volume lies in the fact it has a hidden narrative structure. Complexity is introduced in stages; solutions to the problems are attainable goals. One is drawn in, it is fun to go on. And the book is decorated with fascinating short stories of pharmaceutical design and utility. We have here a rare instance of a well-designed workbook that constructs a learning experience better than that found in most textbooks. What more would I want to see in it? The ordinary (of reasonable Lewis structures, normal bond lengths, moderate temperature [T less than ~100 °C]) which is the province of the beautiful compounds that are discussed in this book, needs to be defined. The ordinary is not diminished by what constrains it, for the fantastic variety the normal world generates suffices. But it is good to be aware of just what the assumptions are. Let me give an example. In one problem, a set of isomers of a bicyclic compound (cyclothiazide) is eliminated from discussion because a bridge can be formed only by cis fusion. In another example, two isomers of a [CoCl2(H2NNH2)(PPh3)2] complex are said to be not possible, those where the H2NNH2 would bridge trans-positions on the octahedral metal. Indeed, both statements make sense, but it would be interesting to mention why they are true (strain, the long N–N bond necessary). And how it is in the nature of chemists to subvert the impossible, and what ingenious molecules might do if there is no option but the energetically costly impossible. “Stereochemistry Workbook,” one of the most effective pedagogical texts I’ve encountered, re-emphasizes the fundamental role of geometry in chemistry. Molecules have shapes. The logic of isomerism, in all its manifestations, the life-and-death-determining necessity of describing three-dimensional geometry, our representational struggles to do so – these define the beauty of chemistry.