cssi/SciSciGPT-SciSciNet huggingface dataset:
Opiate modification of intracranial self-stimulation in the rat.

Abstract Studies were conducted to confirm the involvement of central opiate receptors in the expression of opiate modulation of intracranial self-stimulation (ICSS). Biphasic, dose-related changes in ICSS responding are described following IP administration of morphine sulfate (1–25 mg/kg) and levorphanol tartrate (LEV, 0.5–5 mg/kg). Similar patterns of response modification are reported following intraventricular (IVt) administration of LEV (0.01–0.2 μMoles) LEV's enantiomorph, dextrorphan, was not found to elicit comparable effects after either IP or IVt administration. Both the facilitatory and the depressant phases of LEV's action were antagonized by naltrexone (10 μg, IVt), which had no apparent effect on ICSS by itself. Complete tolerance developed to the suppression of responding by 2.5 mg/kg LEV (IP) but not to the facilitatory effect of 0.5 mg/kg (IP), during a 5-day course of administration. The implications of these results for opiate reinforcement theory are discussed and possible mechanisms are advanced.
Pulmonary vascular response to atrial septal defect closure in children.

Abstract Results related to mean pressure and flow measurements were in the anticipated direction. Pulmonary blood flow described as a result of defect closure and pulmonary pressures, in the normal range before closure, tended to remain the same; hence, the external work of the right heart decreased significantly. Changes in the differential pulmonary vascular resistance and the impedance spectrum indicated that there was an immediate pulmonary vascular response to defect closure. After closure, the differential pulmonary vascular resistance tended to increase, the frequency of the first minimum value of the impedance modulus curve tended to be higher, and the absolute value of the phase angle of the first harmonic tended to be larger. Analysis using a three-segment transmission line model suggests that closure of atrial septal defects results in changes in the pulmonary circulation characterized by either (1) changes in the major reflection site or (2) dilatation and stiffening of proximal arterial vessels accompanied by vasoconstriction or decreased number of microcirculatory vessels perfused. The parameters of the model are also being computed for a group of adult patients with atrial septal defects and a group of normotensive children with ventricular septal defects. Comparisons of the parameter values and/or changes in the parameter values as a result of defect correction in these patients may offer additional insight into causes of the changes observed in the impedance spectra as a result of defect closure.
A comparison of existing grouping efficiency measures and a new weighted grouping efficiency measure

Grouping efficiency is an evaluative measure of the machine-part groups in cellular manufacturing systems. This paper presents briefly both a critical review and a comparative study of different measures of grouping efficiency. Special emphasis is given to the evaluation of the goodness of clustering solutions in the block-diagonalization of the machine-part incidence matrix. The measures are reported both descriptively and quantitatively. In order to provide information on the measures, results are collected and compiled from discretely reported sources. An attempt is made to categorize and generalize these measures in order to use them for goodness of clustering solution. In order to overcome a number of drawbacks in the previously known measures, a new weighted measure is presented and its performance is demonstrated through several perspectives of evaluation of efficiency measures.
Response to C. Christine Fair

When The Journal of Strategic Studies approached me to write a rejoinder to a forthcoming review that ‘raised serious concerns’ about my book, it was beyond belief that a journal of such repute wou...
Undercooling and supersaturation of alloying elements in rapidly solidified Al-8.5% Fe-1.2% V-1.7% Si alloy

Dispersion-strengthened Al-8.5% Fe-1.2% V-1.7% Si alloy was produced by inert gas atomization and atomized melt deposition processes. Differential scanning calorimetry was used to estimate the extent of undercooling in the alloy powders as a function of powder size and in the atomized melt-deposited alloy as a function of process parameters. The estimated undercooling was found to be a strong function of powder size and processing conditions and varied from 380−200 °C. Alloy powders of diameter greater than 180 jam did not experience any undercooling during solidification. X-ray diffraction analysis was performed to study the dependence of supersaturation of alloying elements and metastable phase formation on the extent of undercooling. When the undercooled alloy was heated to about 400 dgC, formation of Al12(Fe, V)3Si phase with b c c crystal structure from the supersaturated matrix was observed.
Heats of transport from diffusion thermoeffect measurements on binary liquid mixtures of carbon tetrachloride with benzene, toluene, 2-propanone, n-hexane, and n-octane

Measurements of heats of transport are reported for binary liquid mixtures containing carbon tetrachloride and benzene, toluene, 2‐propanone, n‐hexane, or n‐octane at 298 K and ambient pressure. Additionally, measurements were made at 308 K for carbon tetrachloride with benzene, toluene, and 2‐propanone. The corresponding heat‐mass Onsager coefficients are also reported, from which thermal diffusion ratios have been calculated based on Onsager reciprocity. These data will be used in a companion paper to report a modified Enskog method for correlation and prediction of heats of transport.
Experimental Study of Turbulent Flow Heat Transfer and Pressure Drop in a Plate Heat Exchanger With Chevron Plates

Experimental heat transfer and isothermal pressure drop data for single-phase water flows in a plate heat exchanger (PHE) with chevron plates are presented. In a single-pass U-type counterflow PHE, three different chevron plate arrangements are considered: two symmetric plate arrangements with {beta} = 30 deg/30 deg and 60 deg/60 deg, and one mixed-plate arrangement with {beta} = 30 deg/60 deg. For water (2 < Pr < 6) flow rates in the 600 < Re < 10{sup 4} regime, data for Nu and f are presented. The results show significant effects of both the chevron angle {beta} and surface area enlargement factor {phi}. As {beta} increases, and compared to a flat-plate pack, up to two to five times higher Nu are obtained; the concomitant f, however, are 13 to 44 times higher. Increasing {phi} also has a similar, though smaller effect. Based on experimental data for Re {ge} 1000 and 30 deg {le} {beta} {le} 60 deg, predictive correlations of the form Nu = C{sub 1}({beta}) D{sub 1}({phi}) Re{sup p1({beta})} Pr{sup 1/3} ({mu}/{mu}{sub w}){sup 0.14} and f = C{sub 2}({beta}) D{sub 2}({phi}) Re{sup p2({beta})} are devised. Finally, at constant pumping power, and depending upon Re, {beta}, and {phi}, the heat transfermore » is found to be enhanced by up to 2.8 times that in an equivalent flat-plate channel.« less
Services to prevent child placing-out for cocaine-affected and non-affected families

This study sought to evaluate the effectiveness of the‘In-Home Family Care’ programme of Children's Home Society of California in Alameda County, particularly regarding the emphasis and impact of services for cocaine-affected families. The family characteristics, problems addressed and service provision in cases served over a 3-year period were assessed in terms of their relation to placement outcome for cocaine-affected and non-affected families. This evaluation found that, despite serious and often chronic problems among cocaine-affected families, their child removal rate was no higher than that for non-affected families. Implications for risk assessment and placement decisions are discussed.
Age hardening-grain size relationships in 18Ni maraging steels

Abstract The interrelationship between prior austenite grain size and age hardening is examined in 18Ni maraging steels. It is shown that the Hall-Petch relationship is obeyed independently of the heat-treatment condition or alloy content. Although the yield strength of unaged 18Ni maraging steels is almost independent of prior austenite grain size, i.e., ky is quite low, in the aged condition the grain size-yield strength dependence approaches that of pure iron. These differences are related to (a) the presence of a dislocated lath substructure in unaged maraging steel, and (b) the effects of solute content variation on the Hall-Petch parameters, ky and σo. Finally, it is shown that coarse grained, high strength maraging steels can fail catastrophically. This failure involves intergranular dimple crack propagation, the latter depending upon the attainment of a critical fracture stress within the near grain boundary region.
Linear-scaling density-functional theory with Gaussian orbitals and periodic boundary conditions: Efficient evaluation of energy and forces via the fast multipole method

We report methodological and computational details of our Kohn-Sham density-functional method with Gaussian orbitals for systems with periodic boundary conditions. Our approach for the Coulomb problem is based on the direct space fast multipole method, which achieves not only linear scaling of computational time with system size but also very high accuracy in all infinite summations. The latter is pivotal for avoiding numerical instabilities that have previously plagued calculations with large bases, especially those containing diffuse functions. Our program also makes extensive use of other linear-scaling techniques recently developed for large clusters. Using these theoretical tools, we have implemented computational programs for energy and analytic energy gradients (forces) that make it possible to optimize geometries of periodic systems with great efficiency and accuracy. Vibrational frequencies are then accurately obtained from finite differences of forces. We demonstrate the capabilities of our methods with benchmark calculations on polyacetylene, polyphenylenevinylene, and a (5,0) carbon nanotube, employing basis sets of double zeta plus polarization quality, in conjunction with the generalized gradient approximation and kinetic-energy density-dependent functionals. The largest calculation reported in this paper contains 244 atoms and 1344 contracted Gaussians in the unit cell.
Electron microscopic studies of temperature-sensitive mutants of herpes simplex virus type 1.

Abstract Fifteen temperature-sensitive (ts) mutants of herpes simplex virus type 1, each representing a single complementation group, were found to fall into three classes with regard to the degree of defectiveness in virion synthesis which they exhibited at the nonpermissive temperature (39°) when examined by electron microscopy. Mutants in class A, one DNA and one DNA + , failed to synthesize detectable particles. Mutants in class B, three DNA − and four DNA + , synthesized small to moderate numbers of empty nucleocapsids. An unique cylindrical core form was observed in particles synthesized after infection with a class B mutant at 39°. Six DNA + mutants in class C synthesized large numbers of virus particles most of which contained apparently empty nucleocapsids. In addition, five of the six mutants synthesized small to moderate numbers of dense-cored nucleocapsids and of these, two formed enveloped, dense-cored particles. The ultrastructural appearance of cells infected with one class C mutant at 39° resembled wild-type virus-infected cells at this temperature, yet it produced 10,000-fold less infectious virus than cells infected with the wild-type virus.
The effects of age on finger temperature responses to local cooling.

Abstract Finger temperature measurements were made before, during, and after a period of immersion of the hand in a 10° C. water bath on healthy individuals varying in age from 6 to 83 years. The hunting reaction tended to occur less frequently with the advancing age of the subjects. Similarly the rates of cooling and rewarming of the finger appeared to be influenced by the age of the individual. It is suggested that these differences in response to a local cold stimulus were related to changes in vascular reactivity.
Gender-related effects on metoprolol pharmacokinetics and pharmacodynamics in healthy volunteers

Objective To determine whether there are gender-specific differences in the pharmacokinetics and pharmacodynamics of metoprolol enantiomers. Methods Twenty normal volunteers (10 men and 10 women) received 100 mg oral metoprolol tartrate twice daily for a total of nine doses. Pharmacokinetics and pharmacodynamics were studied after the last dose. Subjects also completed a control pharmacodynamic study; the order of drug and control studies was randomized. Measurements of heart rate and systolic blood pressure were obtained during peak submaximal bicycle exercise testing. (R)-Metoprolol and (S)-metoprolol concentrations were determined by stereospecific HPLC. The percentage difference in exercise heart rate and systolic blood pressure (metoprolol versus control), and (R)- and (S)-metoprolol plasma concentrations were comodeled. Results Men and women showed stereoselective pharmacokinetics; (S)-metoprolol concentrations were significantly greater than those for (R)-metoprolol for both groups. Women had greater drug exposure than men (higher maximum concentration and area under the plasma concentration–time curve). No differences were observed between genders with respect to elimination half-life. Females had a greater reduction in exercise heart rate and systolic blood pressure; however, the area under the effect curve was significantly greater for heart rate only. Pharmacodynamic data were best fitted by the Hill equation with the effect site in the central compartment. The fitted maximum effect and the concentration at one-half of the maximum effect for heart rate and systolic blood pressure did not differ between men and women (P > .20). Conclusions Gender-related differences exist in the pharmacokinetics of metoprolol enantiomers, resulting in greater drug exposure in female subjects. However, concentration–effect relationships did not differ between men and women. Therefore the observed differences in drug effects were the result of gender-specific differences in metoprolol pharmacokinetics. Clinical Pharmacology & Therapeutics (1999) 66, 594–601; doi: 10.1053/cp.1999.v66.103400001
Epidemiology in Early Childhood Education.

Early childhood educators are keen observers of young children, and as such are important sources of information about the health and safety of young children. This paper discusses the importance to quality early childhood programs of an epidemiological approach to those observations. Surveillance is described using examples from the literature on preschoolers’ unintentional injuries. Basic epidemiological measurements (count, rate, incidence, prevalence) as well as the constructs of descriptive epidemiological studies (e.g., prospective, retrospective) are also presented using examples from early childhood health and safety studies. A five step plan to conduct an epidemiological study (define the problem, literature review, protocol, data collection, data analysis) is outlined. The importance of teachers providing first‐hand documentation of health, safety and development of young children is stressed.
Open Problems on the Eve of the Next Millennium

To predict the future of Celestial Mechanics and to investigate unsolved problems for the next millennium contradicts the nature of our field of science which is based on non-integrable and transcendental equations with short time predictability. The reliability and predictability in our field depend on several factors, most of them unpredictable. Numerical predictions depend on the development of computer technology, which is itself not predictable. New analytical approaches call for the genius of Newton. We mustrealize that between Ptolemaeus (100–178) and Copernicus (1473–1543) our field received little attention. Between 1700 and 1800 the explosion occurred (Newton, Euler, Laplace, Lagrange and Gauss) followed by the period of 1800–1900 associated with Hamilton, Hill, Jacobi, Poincare and Tisserand. Can we expect anyone to make similar contributions in the next 1000 years?
Anomalous Left Coronary Artery From the Pulmonary Artery (ALCAPA)

Anomalous left coronary artery from the pulmonary artery, or ALCAPA, is a rare, congenital cardiac anomaly. The condition causes ischemia and, if left untreated, can lead to death. It is important for cardiac sonographers to recognize the signs, symptoms, and sonographic characteristics of ALCAPA. A case of ALCAPA diagnosed by echocardiography is presented.
CONGENITAL MID URETERAL STRICTURES

ABSTRACT Purpose: Congenital mid ureteral stricture is rare. We report 7 cases, and discuss the differences in preoperative evaluation and surgical management compared to other obstructive entities. Materials and Methods: Medical records and imaging studies of 7 children identified with mid ureteral strictures between 1998 and 2002 were reviewed retrospectively. Five newborns presented with prenatal hydronephrosis, and 2 children presented at age 15 years, one in the course of evaluation of blunt trauma, and one due to pain and abdominal mass. Imaging studies included renal ultrasound, voiding cystourethrography, radionuclide renography and computerized tomography. All patients underwent retrograde pyelography. Pathological examination of each specimen was undertaken at the respective institutions. Results: Prenatal hydronephrosis was the most common presentation. There were no urinary tract infections. All patients had significant obstruction on the affected side. No patient had vesicoureteral reflux. After imaging but before surgery the urinary obstruction was believed to be at the ureteropelvic junction in 4 patients and the ureterovesical junction in 2, and secondary to posterior urethral valves in 1. At cystoscopy all of the affected ureters had a normally located and normally configured orifice. Retrograde pyelography led to an accurate diagnosis of mid ureteral narrowing in all patients. Six patients underwent ureteroureterostomy, all of whom had satisfactory outcomes. In 1 of these patients contralateral nephrectomy was performed due to nonfunction of the multicystic dysplastic kidney. The remaining patient underwent nephrectomy for ipsilateral end stage kidney disease and hydronephrosis. In this patient the ureters were stenotic and suggested asymmetry in the thickness of the muscular coat, perhaps secondary to extrinsic compression. Conclusions: Congenital mid ureteral stricture is rare. Renal ultrasound and radionuclide renography alone do not reliably demonstrate the site of obstruction. Retrograde pyelography at the time of surgical correction of presumed ureteral obstruction is an important adjunct for correctly identifying the site of narrowing in the affected ureteral segment, unless the ureter has been imaged with another modality.
Neurofibromatosis and intracranial arterial occlusive disease.

Two cases of neurofibromatosis and intracranial arterial occlusive disease are reported. The radiographic and clinical features of these and twelve previously reported cases are reviewed.
The Effects of Sex and Gender Role Orientation on Mentorship in Male-Dominated Occupations.

Abstract This study examined the relative impact of sex and gender role orientation on the development and functions of mentoring relationships in Certified Public Accounting, a male-dominated occupation. Results showed that biological sex was not related to mentoring, yet gender role orientation was significantly related to having a mentor and mentor functions. Individuals with androgynous sex role orientations reported more mentorship functions than individuals with feminine or masculine orientations. Implications and areas for future research are discussed.
Beyond user friendly—towards the assimilation of multifunctional-workstation capabilities

Abstract This paper develops, describes and critiques an integrated, theoretical model which provides a framework for studying and planning performance-improvement programs for users working with the capabilities of multifunctional workstations. The performance-improvement block interaction model focuses on three facets of performance improvement: (i) individual and group substitution and augmentation skills, (ii) man-computer interface design, and (iii) organizational philosophy. The variables depicted in the model are derived largely from two existing models and a previous empirical study which are also described in the paper. These variables will interact with the above three facets to determine the extent of multifunctional-workstation utilization. One variable, the concept of user augmentation skills, is unique to the performance-improvement block interaction model. Thus, one section of the paper explains augmentation skills and the relationship of these skills to multifunctional-workstation utilization.
Facilitated transport of 6-mercaptopurine and 6-thioguanine and non-mediated permeation of 8-azaguanine in novikoff rat hepatoma cells and relationship to intracellular phosphoribosylation

Abstract 6-Mercaptopurine and 6-thioguanine strongly inhibited the zero- trans entry of hypoxanthine into Novikoff rat hepatoma cells which lacked hypoxanthine/guanine phosphoribosyltransferase, whereas 8-azaguanine had no significant effect. 6-Mercaptopurine was transported by the hypoxanthine carrier with about the same efficiency as its natural substrates (Michaelis-Menten constant = 372 ± 23 μ M; maximum velocity = 30 ± 0.7 pmol/ μ l cell H 2 O per s). 8-Azaguanine entry into the cells, on the other hand, showed no sign of saturability and was not significantly affected by substrates of the hypoxanthine/guanine carrier. The rate of entry of 8-azaguanine at 10–100 μM amounted to only about 5% of that of hypoxanthine transport and was related to its lipid solubility in the same manner as observed for various substances whose permeation through the plasma membrane is believed to be non-mediated. Only the non-ionized form of 8-azaguanine (p K a = 6.6) permeated the cell membrane. Studies with wild type Novikoff cells showed that permeation into the cell was the main rate-determining step in the conversion of extracellular 8-azaguanine to intracellular aza-GTP and its incorporation into nucleic acids. In contrast, 6-mercaptopurine was rapidly transported into cells and phosphoribosylated; the main rate-determining step in its incorporation into nucleic acids was the further conversion of 6-mercaptopurine riboside 5'-monophosphate.
β-catenin is a downstream effector of Wnt-mediated tumorigenesis in the mammary gland

The Wnt signal transduction pathway has been implicated in mammary tumorigenesis in the mouse. beta-catenin, a key downstream effector of this pathway interacts with and thus activates the Tcf/Lef family of transcription factors. Elevated levels of beta-catenin have been found in many human tumors, notably colon carcinomas. Recently, elevated levels of beta-catenin have been associated with poor prognosis in human adenocarcinoma of the breast. In order to assess the possible role of beta-catenin in mammary carcinoma, we have created transgenic mice bearing the MMTV-LTR driving an activated form of beta-catenin. These mice develop mammary gland hyperplasia and mammary adenocarcinoma, a phenotype very similar to that of transgenic mice expressing an MMTV-driven Wnt gene. Indeed, the histopathology of the mammary tumors in Wnt-mediated adenocarcinoma is identical to that observed in our beta-catenin-mediated disease model. Furthermore, putative beta-catenin transcriptional targets, cyclin D1 and c-myc, are elevated in beta-catenin-mediated mammary tumors and cell lines. These observations support the notion that the oncogenic Wnt pathway operates via beta-catenin and its targets in the context of mammary hyperplasia and carcinoma.
Analysis of some nonrandom mating models

Abstract In this paper a few asymmetric models are presented taking account of the effects of assortative mating on an autosomal trait controlled by a single locus possibly with multiple alleles. The models are developed by specifying the intensities for preference mating for various phenotypes. The analysis is confined to the case in which preference is exercised by the individuals of one sex only. It is assumed that males possess unlimited fertility. The dynamics of the population and its equilibrium distribution are discussed. The gene frequency usually changes with time and equilibrium distribution in most cases depends only on the assortment parameters. Expressions are obtained giving the additive and dominance components of variance, and covariances for relatives for populations in equilibrium for some of the models.
Biomechanical comparison of two plating techniques for fixation of acetabular osteotomies in dogs.

Objective— To compare the failure properties of a 5-hole, 2.7-mm curved acetabular plate (AP) to a 5-hole, 3.5-mm reconstruction plate (RP) when applied to acetabular osteotomies. Study Design— Cadaver study. Animals or Sample Population— Pelves of 8 mature, large-breed dogs. Methods— A 5-hole, 2.7-mm AP and a 5-hole, 3.5-mm RP were contoured and applied to the dorsal acetabulum of each pelvis. A central acetabular fracture was simulated after plate application by a transverse osteotomy with a fine saw. Each acetabulum was loaded in a weight-bearing direction. A load-deformation curve was produced for each construct, and biomechanical properties of the AP and RP were compared with the Student's paired t-test. A P value of < .05 was considered significant. Results— For the AP and RP composite respectively, the mean ± SD maximum load to failure was 2,721 ± 632 N and 2,488 ± 800 N, the stiffness was 4.8 ± 1.8 N/m and 5.3 ± 1.9 N/m, and the energy absorbed was 15.1 ± 5.2 Nm and 16.3 ± 8.3 Nm. None of these differences was statistically significant. Conclusions— Both fixation techniques provided comparable strength, stiffness, and energy absorbed under the loading conditions of this study. Clinical Relevance— Because of the relative ease of application, the 2.7-mm curved AP may be the practical choice for acetabular fracture repair in large dogs.
Hormonal priming and triggering of maternal behavior in the rat with special reference to the relations between estrogen receptor binding and ER mRNA in specific brain regions.

Estrogen stimulation of maternal behavior during pregnancy in the rat has been studied at several levels of analysis. These include (a) changes in maternal responsiveness during pregnancy; (b) hormonal stimulation of maternal behavior; and (c) correlation between nuclear binding of estradiol in the medial preoptic area and the stimulation of maternal behavior (i.e., in pregnancy-terminated, ovariectomized females treated with estradiol benzoate). These studies have given rise to the concepts of hormonal priming and triggering of maternal behavior during pregnancy and at parturition. More recently, using in situ hybridization, ER mRNA was measured during pregnancy (also diestrus and postpartum) in brain regions in which binding previously had been studied, to investigate further the regulation of hormonal priming. Steady state levels of ER mRNA per cell and cell densities of ER mRNA produced a measure of total ER mRNA per brain region which was then compared to nuclear estrogen receptor binding. The relation between binding and ER mRNA is presented for one of the brain regions, the rostral medial preoptic nucleus. The results indicate that ER transcription is regulated during pregnancy, but regulation is specific to each brain region and there is no simple relation between ER mRNA and nuclear estrogen receptor binding.
Auto-adjusting and Advanced Positive Airway Pressure Therapeutic Modalities

Continuous positive airway pressure (CPAP) therapy is the first-line treatment for obstructive sleep apnea (OSA). Although the gold standard for the treatment of OSA, CPAP may not be the optimal modality to treat more complex sleep disordered breathing such as Cheyne-Stokes respirations, opioid-induced central apnea, and complex sleep disordered breathing related to chronic hypoventilation syndromes (obesity-hypoventilation syndrome, restrictive thoracic disease due to neuromuscular or thoracic cage disease, chronic obstructive pulmonary disease). Newer generation auto-adjusting PAP devices are increasingly being used to treat OSA. Advanced positive airway pressure modalities have been developed in an effort to improve treatment of the more complex sleep disordered breathing syndromes including automated servo ventilation and volume-targeted pressure-limited ventilation. This article is intended to provide the clinician reader with a description of newer PAP modalities, a review of evidence-supported indications for use, as well as to provide a framework for managing patients with advanced positive airway pressure therapy.
University-industry programs.

In the report by R. G. Wyatt et al. "Human rotavirus type 2: Cultivation in vitro" (11 Jan., p. 189), in the sentence describing the porcine rotavirus plaque reduction test (p. 190, column 3, line 16), the concentration of pancreatin in the agar overlay should have been given as "0.15 percent of 2.5 percen pantreatin 4 x N. F.; Gibco."
Ontogeny and plasticity of adult hippocampal neural stem cells.

We have investigated the ontogenetic origin and the degree of plasticity of adult hippocampal neural stem cells. Wnt1-expressing cells are located at the dorsal aspect of the embryonic neural tube and some of them are predestined to give rise to neural crest stem cells. Whereas the majority of adult hippocampal neural stem cells do not originate from cells that express Wnt1, a subset does express Wnt1 transiently during embryogenesis, as determined in the double transgenic mouse, Wnt1-cre/R26R. Hippocampal stem cells from adult ROSA 26 mice differentiate into chondrocytes, melanocytes (pigment cells) and smooth muscle cells when cocultured with neural crest cells from quail embryos. Neural crest cell-generated stimuli have a short-range of action and are recognized across species. These observations provide evidence for the heterogeneity in the hippocampal neural stem cell pool with regard to Wnt1 expression. Furthermore, they show plasticity and a remarkably wide range of developmental options of adult hippocampal stem cells.
Management of recurrent hepatitis C after liver transplantation: a concise review

Recurrent hepatitis C infection and subsequent graft failure are increasingly recognized problems after orthotopic liver transplantation. Although many prospective therapeutic, controlled trials in primary hepatitis C disease have been reported, large-scale studies are yet to be performed in patients with posttransplant recurrent hepatitis C after liver transplantation. In this review, we summarize the current literature on the therapeutic approaches for recurrent hepatitis C and discuss the results of published studies on therapy with ribavirin or interferon (IFN) alone and on combination therapy with IFN plus ribavirin. Further, we discuss results of prophylactic approaches to the problem of recurrent hepatitis C after transplant. Finally, we discuss additional aspects of anti-hepatitis C virus therapy after liver transplantation.
Clinical Relevance of Polyamines

The polyamines, putrescine, spermidine, and spermine have been established as biochemical markers of normal and pathological growth. In malignancy, the urinary concentrations of spermidine reflect the tumor cell loss and the urinary level of putrescine is related both to the number of tumor cells in cell cycle and to the tumor cell loss factor. A greater than twofold increase in urinary spermidine within 72 hr of chemotherapy predicts a complete or a partial response with a high degree of accuracy. Urinary putrescine may be valuable, not only in assessing the early response to therapy but also in determining whether the chemotherapy promotes a later burst of cell proliferation. Erythrocyte spermidine concentrations also appear to track alterations in tumor kinetics. Alterations in intracellular and extracellular polyamines in other pathologies such as psoriasis, muscular dystrophy, and cystic fibrosis also accurately reflect the disease activity and, in those cases studied, response to therapy. Therefore, the determination of polyamine concentrations in extracellular fluids and in erythrocytes allows for (1) the early assessment of response to multimodality therapy, (2) disease or tumor staging, and (3) assessment of disease activity including long-term monitoring of polyamine concentrations to pinpoint remission and relapse in adjuvant patients. Information obtained by the monitoring of polyamines could result in prolongation of survival time of patients as well as assist in the design of the most effective therapy regimen for the pathology. Since other such specific kinetic markers are not available, polyamines should be clinically utilized to track tumor evolution and tumor response to therapy in those patients at high risk, in which such measurements could be translated into therapeutic efficacy.
Summary of the Status of Lasers for Inertial Confinement Fusion

Laser systems designed for plasma research are operating in many laboratories throughout the world. The laser performance itself has become reasonably consistant from laboratory to laboratory and the focusing properties of the laser beams are understood. The plasma physics data, obtained with these systems, also appears to be reasonably self-consistant and is of great interest for inertial fusion applications. These lasers are commonly providing output powers of 0.5 > 2 TW, and power densities on target of 10/sup 13/-10-/sup 16/ W/cm/sup 2/, pulse durations on the order of 100 psec to 3 nsec, wavelengths between 0.5 ..mu.. and 10 ..mu.., and focal spot sizes of 100 ..mu.. or larger where focal spot edge effects are becoming less dominant. In addition, spurious target responses due to such behavior as pre-pulses, self-focusing, or imprecise focal spot measurement are being observed less often. The technical problems of large multi-beam systems, performing at the 10 TW level, have been overcome and these systems (e.g. the Shiva and Helios lasers) are providing high density compression data with ablative targets. The next step in laser design, the 100 to 300 kJ systems, are under construction and 1 MJ lasers are being contemplated.
Towards geospatial semantic search: exploiting latent semantic relations in geospatial data

This paper reports our efforts to address the grand challenge of the Digital Earth vision in terms of intelligent data discovery from vast quantities of geo-referenced data. We propose an algorithm combining LSA and a Two-Tier Ranking (LSATTR) algorithm based on revised cosine similarity to build a more efficient search engine – Semantic Indexing and Ranking (SIR) – for a semantic-enabled, more effective data discovery. In addition to its ability to handle subject-based search, we propose a mechanism to combine geospatial taxonomy and Yahoo! GeoPlanet for automatic identification of location information from a spatial query and automatic filtering of datasets that are not spatially related. The metadata set, in the format of ISO19115, from NASA's SEDAC (Socio-Economic Data Application Center) is used as the corpus of SIR. Results show that our semantic search engine SIR built on LSATTR methods outperforms existing keyword-matching techniques, such as Lucene, in terms of both recall and precision. Moreover...
Estimating Effects of Tidal Power Projects and Climate Change on Threatened and Endangered Marine Species and Their Food Web

Marine hydrokinetic power projects will operate as marine environments change in response to increased atmospheric carbon dioxide concentrations. We considered how tidal power development and stressors resulting from climate change may affect Puget Sound species listed under the U.S. Endangered Species Act (ESA) and their food web. We used risk tables to assess the singular and combined effects of tidal power development and climate change. Tidal power development and climate change posed risks to ESA-listed species, and risk increased with incorporation of the effects of these stressors on predators and prey of ESA-listed species. In contrast, results of a model of strikes on ESA-listed species from turbine blades suggested that few ESA-listed species are likely to be killed by a commercial-scale tidal turbine array. We applied scenarios to a food web model of Puget Sound to explore the effects of tidal power and climate change on ESA-listed species using more quantitative analytical techniques. To simulate development of tidal power, we applied results of the blade strike model. To simulate environmental changes over the next 50 years, we applied scenarios of change in primary production, plankton community structure, dissolved oxygen, ocean acidification, and freshwater flooding events. No effects of tidal power development on ESA-listed species were detected from the food web model output, but the effects of climate change on them and other members of the food web were large. Our analyses exemplify how natural resource managers might assess environmental effects of marine technologies in ways that explicitly incorporate climate change and consider multiple ESA-listed species in the context of their ecological community. Estimacion de los Efectos de Proyectos de Energia de las Mareas y el Cambio Climatico sobre Especies Marinas Amenazadas y en Peligro y su Red Alimentaria.
Ensemble Predictions of the 2012 US Presidential Election

or more than two decades, political scientists have created statistical models aimed at generating outof-sample predictions of presidential elections. In 2004 and 2008, PS: Political Science and Politics published symposia of the various forecasting models prior to Election Day. This exercise serves to validate models based on accuracy by garnering additional support for those that most accurately foretell the ultimate election outcome. Implicitly, these symposia assert that accurate models best capture the essential contexts and determinants of elections. In part, therefore, this exercise aims to develop the “best” model of the underlying data generating process. Scholars comparatively evaluate their models by setting their predictions against electoral results while also giving some attention to the models’ inherent plausibility, parsimony, and beauty. Our approach is different. Rather than creating the best model or theory, instead we create an ensemble prediction of the upcoming election. We combine the intuition, theories, and concepts implicit in all of the forecasting models presented in this symposium to make an accurate out-of-sample prediction. Without arbitrating between models and theories, we aim to aggregate them solely with an eye toward increasing our chances of getting it right. To do this, we rely on the models presented in this issue. We believe that each model captures an important set of insights about US elections. Our approach combines those insights into a single ensemble prediction. For our purposes, the theoretical differences between the models are irrelevant. All that matters is that each provides predictions for previous elections that we can use to evaluate their accuracy. We then weight each forecast by its previous performance and combine them to create the most accurate out-of-sample forecast possible that also captures the uncertainty and diversity inherent in these models.
Electron microscopy of human dentin exposed by attrition.

– Undecalcified sections of human dentin exposed by attrition were studied by electron microscopy. Many tubules contained calcified deposits or inclusions with a high degree of variability in structure and density. The presence of big crystals, some needle-like, others angulated and often rhombohedral, was conspicuous. The deposits seemed to be formed by a precipitation of minerals in the lumen, or by a repetitive deposition on the walls of the tubules. In the region of the last formed primary dentin, tubules without peritubular dentin occurred. Most of the tubules of the irritation dentin were surrounded by peritubular dentin of varying width and density. Groups of tubules contained a great amount of mineralized collagenous fibers, oriented parallel to the long axis of the tubule. The large angulated crystals were also present in tubules of the irritation dentin. Electron diffraction patterns indicated that the big needle-like crystals were apatite in nature whereas the inclusions seemed to contain whitlockite when the angulated, rhombohedral crystals were present.
Two Distinct DNA Ligase Activities in Mitotic Extracts of the Yeast Saccharomyces Cerevisiae

Four biochemically distinct DNA ligases have been identified in mammalian cells. One of these enzymes, DNA ligase I, is functionally homologous to the DNA ligase encoded by the Saccharomyces cerevisiae CDC9 gene. Cdc9 DNA ligase has been assumed to be the only species of DNA ligase in this organism. In the present study we have identified a second DNA ligase activity in mitotic extracts of S. cerevisiae with chromatographic properties different from Cdc9 DNA ligase, which is the major DNA joining activity. This minor DNA joining activity, which contributes 5-10% of the total cellular DNA joining activity, forms a 90 kDa enzyme-adenylate intermediate which, unlike the Cdc9 enzyme-adenylate intermediate, reacts with an oligo (pdT)/poly (rA) substrate. The levels of the minor DNA joining activity are not altered by mutation or by overexpression of the CDC9 gene. Furthermore, the 90 kDa polypeptide is not recognized by a Cdc9 antiserum. Since this minor species does not appear to be a modified form of Cdc9 DNA ligase, it has been designated as S. cerevisiae DNA ligase II. Based on the similarities in polynucleotide substrate specificity, this enzyme may be the functional homolog of mammalian DNA ligase III or IV.
The effect of corporate governance on firm’s credit ratings: further evidence using governance score in the United States

AbstractWe investigate whether corporate governance aﬀects ﬁrms’ credit ratings andwhether improvement in corporate governance standards is associated withimprovement in investment grade rating. We use the Gov-score of Brown andCaylor (2006), the Gomper’s G index and an entrenchment score of Bebchuket al. (2009) to proxy for corporate governance. Using a sample of US ﬁrms, weﬁnd that ﬁrms characterized by stronger corporate governance have a signiﬁ-cantly higher credit rating, and that this association is accentuated for smallerﬁrms relative to larger ﬁrms. We ﬁnd that an improvement in corporate gover-nance is associated with improvement in bond rating.Key words: Corporate governance; Credit ratings; Changes in corporategovernance; Changes in credit ratingsJEL classiﬁcation: G24, G32, G34doi: 10.1111/j.1467-629X.2010.00396.x1. IntroductionIn this study, we use the methodology developed by Ashbaugh-Skaife et al.(2006) to examine the inﬂuence of corporate governance on a ﬁrm’s creditratings. The issue of corporate governance has become more important becauseof the highly publicized ﬁnancial reporting frauds at Enron, Worldcom andParmalat (Palmrose and Scholz, 2004). One of the most important functions of
Energy coupling factor as target of colicin K: characterization of a colicin K-insensitive ecf mutant of Escherichia coli.

We isolated a colicin K-insensitive energy uncoupled mutant of Escherichia coli . This mutant was presumed to be an ecf mutant as evidenced by its similarity to a known ecf mutant (M. A. Lieberman and J.-S. Hong, 1974) with respect to the mutational site, reversion pattern, and defects in transport and growth. The mutation conferring the colicin K-insensitivity resided in the ecf gene as the majority of the secondary mutations overcoming the ecf phenotype reverted the colicin K-insensitive phenotype to colicin K-sensitive. The insensitivity of the mutant to colicin K was not due to either a defect in adsorption or to a lack of the energized membrane state. The defect was most probably due to the inability of colicin K molecules to interact with their target. Our previous studies concerning the role of the ecf gene product in energy coupling to active transport and oxidative phosphorylation support the contention that the ECF protein is itself the direct target of colicin K.
Don't Fence Me In: Boundaries, Policy, and Deliberation in Maine's Lobster Commons

Describing the necessary conditions for collective action in the interest of natural resource conservation, common property theory asserts the need for clear boundaries. This pertains to material boundaries that circumscribe target resources and social boundaries that circumscribe resource user group identities. In reality, socioecological systems are rarely closed or static, so boundary imposition can generate transaction costs and perhaps reduce adaptive capacity if implemented without allowances for broad and repeated public deliberation. Participant observation, interview, survey, archival, and focus group data from Maine's lobster fishery demonstrate that flexible, broadly negotiated, informal boundaries characterized the fishery for decades, embedded in localist institutions under de facto comanagement. Federal regulatory pressures and industry changes triggered formalization of a more statist comanagement regime, overlaying codified boundaries under the guise of resource conservation. Fishing boat ...
Computer architecture for grasping

The Integrated Tactile Network Architecture or ITNA is a hierarchical system for managing the interaction of tactile sensing and motor control in the 3-D active sensory environment. The overall ITNA includes custom dedicated hybrid front end tactile arrays incorporating electronics and microprocessors for sensor linearization, tactile information preprocessing, and local feature extraction approaches to the distributed motor control of manipulator fingers for grasping; interconnection networks for guarded movement and reflex arcs; and special purpose hardware for model generation derived from tactile information. This paper primarily addresses the overall ITNA structure and, in particular, the design of an intelligent sensor array and its associated communications subsystem.
Comparison of two exercise programs on general well-being of college students

Responses to life stressors are associated with negative behaviors that may increase risk for illness and injury. The effect of high intensity exercise in reducing reactivity to psychological stress has been well documented among older people. The purpose of this study was to ascertain the effect of weight-training versus aerobic dance on psychological stress in college students. 45 students participated in a weight-training course, 35 students participated in aerobic dance classes, and 34 students served as a control group. The Survey of Recent Life Experiences was used to appraise stressfulness of current experiences before and after exercise intervention. On immediate retest after 8 wk. of weight-training perceived stress was significantly reduced when compared with an 8-wk. aerobic dance program, but there were no significant differences between the control group and the weight-training group or the aerobic dance group. These results suggest that a regular routine of low intensity exercise such as weight-training may reduce perceived stress on an immediate test.