cssi/SciSciGPT-SciSciNet huggingface dataset:
p53 gene analysis of ovarian borderline tumors and stage I carcinomas

Mutations of the p53 gene are common in human ovarian carcinomas; however, their role in the early development of ovarian cancer is unclear. Twelve ovarian borderline tumors (BTs; eight of them p53 immunopositive) and 10 stage I carcinomas (four of them p53 immunopositive) were studied for genetic alterations in the p53 gene. The study was based on single-strand conformation polymorphism (SSCP) analysis and DNA sequencing of exons 2 through 11 of the p53 gene using DNA preparations from microdissected tumors. Mutations were found in 40% of the carcinomas (including a borderline component adjacent to carcinoma in one lesion) but in none of the pure BTs. These findings suggest that p53 mutations may not be commonly associated with the borderline phenotype of ovarian epithelial tumors but may occur during malignant transformation.
Late embryogenesis and egg eclosion in Triepeolus and Anthophora with a prospectus of nomadine classification (Hymenoptera: Anthophoridae).

Late embryogenesis of Triepeolus dacotensis (Steven) and its host, Anthophora occidentalis Cresson, are described in some detail using in vivo techniques. External and internal structures of the T. dacotensis egg are also described and related to particular functions. Descriptions of eclosion from eggs for both bee taxa are included and the methods used by T. dacotensis to deposit its egg into the cell wall of its host are discussed. Embryological information reported in this study is compared with results obtained in similar studies of other bee taxa to establish preliminary lists of characteristics that distinguish the Apoidea or are diagnostic of particular bee taxa. More specifically, ontogenetic characteristics are incorporated into established classifications of the subfamily Nomadinae, from which an alternate classification prospective is proposed for nomadine bees.
Ferromagnetic exchange coupling in the spinel lattice

Abstract The ferromagnetism of the recently discovered ferromagnetic spinels thought to be due to nearest neighbour Cr 3+ superexchange interactions. The presence of such interactions is confirmed by measurements of the fluorescence of Cr 3+ in the spinel ZnAl 2 O 4 . Structure is observed that may be clearly associated with exchange coupled Cr 3+ pairs with a ferromagnetic exchange constant J = + 10.2 cm −1 .
Overexpression and Purification of the Trimeric Aspartate Transcarbamoylase from Bacillus subtilis

Abstract A procedure has been developed for the overexpression and purification of milligram quantities of the Bacillus subtilis aspartate transcarbamoylase. The plasmid pEK171, carrying the B. subtilis pyrB structural gene under the control of the Escherichia coli pyrBI promoter, was transformed into the E. coli strain EK1104 and the enzyme overexpressed to approximately 50% of total soluble protein under extreme derepression of the pyrimidine pathway. The enzyme was subsequently purified by means of ammonium sulfate fractionation, anionic exchange chromatography using Q-Sepharose Fast Flow resin, negative chromatography on Matrex Gel Red A agarose, and hydrophobic interaction chromatography using Matrex Phenyl Cellufine, The purification yields approximately 60 mg of pure enzyme per liter of bacterial culture. Kinetic analysis of the overexpressed enzyme indicated that it had kinetic properties very similar to those of the enzyme purified from B. subtilis cells.
Membrane effects of cytochalasin B. Competitive inhibition of facilitated diffusion processes in rat hepatoma cells and other cell lines and effect on formation of functional transport sites.

Cytochalasin B competitively inhibits the transport of 2-deoxy-d-glucose and thymidine in a number of different cell lines (Novikoff rat hepatoma cells, mouse L, S180 and Ki-MSV-transformed BALB/3T3 cells, and human HeLa cells). The apparentK m values for the transport of these substrates as well as the apparentK i values for the inhibition by cytochalasin B are very similar for the various cell lines, and the effect is readily and completely reversed by removal of the chemical. Thymidine transport by Chinese hamster ovary cells however, is little affected by cytochalasin B, whereas the transport of 2-deoxy-d-glucose, uridine and guanine by these cells is competitively inhibited to about the same extent as in other cell lines. In addition and concomitant with the inhibition of cytokinesis and an alteration in cell shape, cytochalasin B also impairs and delays the formation of functional transport sites for thymidine, guanine and choline in synchronized populations of Novikoff cells without affecting the apparent affinities of the transport systems for their substrates. This effect is unrelated to the direct inhibition of the transport processes, since the drug does not directly inhibit choline transport and has no effect on the formation of 2-deoxy-d-glucose transport sites in spite of the fact that it strongly inhibits the transport of this substrate. The inhibition of functional transport sites may be due to the induction of a structural alteration in the membrane by cytochalasin B which impairs the insertion of new proteins of certain but not all transport systems into the membrane.
Analysis of human α globin gene mutations that impair binding to the α hemoglobin stabilizing protein

Alpha hemoglobin stabilizing protein (AHSP) reversibly binds nascent α globin to maintain its native structure and facilitate its incorporation into hemoglobin A. Previous studies indicate that some naturally occurring human α globin mutations may destabilize the protein by inhibiting its interactions with AHSP. However, these mutations could also affect hemoglobin A production through AHSP-independent effects, including reduced binding to β globin. We analyzed 6 human α globin variants with altered AHSP contact surfaces. Alpha globin amino acid substitutions H103Y, H103R, F117S, and P119S impaired interactions with both AHSP and β globin. These mutations are destabilizing in biochemical assays and are associated with microcytosis and anemia in humans. By contrast, K99E and K99N α globins bind β globin normally but exhibit attenuated binding to AHSP. These mutations impair protein folding and expression in vitro and appear to be mildly destabilizing in vivo. In Escherichia coli and erythroid cells, α globin K99E stability is rescued on coexpression with AHSP mutants in which binding to the abnormal globin chain is restored. Our results better define the biochemical properties of some α globin variants and support the hypothesis that AHSP promotes α globin chain stability during human erythropoiesis.
D(-)3-hydroxybutyrate cotransport with Na in rat renal brush border membrane vesicles.

Which are the driving forces ford(-)3-hydroxybutyrate (HB) transport in rat renal brush border membranes (RBB)? Sodium, even in the absence of gradients, accelerates the unidirectional (1–5 s) flux of HB into rat RBB vesicles. Valinomycin (andK i=K o) does not significantly alter the NaCl gradient driven HB influx. Thus, the Na-dependent HB influx is driven by the chemical Na+ gradient but it is not driven by changes in the transmembrane electrical potential. Indeed, in valinomycin-treated membranes, vesicle-inside more negative potentials (K-gluconatein-Na-gluconateout) sufficient to accelerate Na-glucose cotransport, did not stimulate HB influx, in the presence of inwardly directed Na+ gradients, and did not significantly inhibit when in the absence of Na+. Thus, cotransport of HB with Na in rat RBB membranes does not involve the net transfer of positive charge and the passive conductance of this membrane for HB− is not large. However, vesicle inside more negative potentials (induced by inwardly directed NaNO3 gradients or by outwardly directed K+ gradients and valinomycin in the presence of inwardly directed Na+ gradients) inhibited HB influx, suggesting that another potential sensitive mechanism, perhaps redistribution of intramembrane charges, may influence HB influx. Acidification (pHi=pHo=6.4 vs. 7.4) or inwardly directed H+ gradients (pHo/pHi=6.4/7.4) did not alter HB influx, in the absence of Na+. Thus there is no evidence for a H+ driven HB influx. HB influx is significantly inhibited by high (100 mEq/l) trans concentration of Na+. Also, influx of 2.25 mM14C-HB was significantly increased by 5–10 mM intravesicular HB under Na-equilibrated conditions. Thus, the rate of translocation of the free carrier appears to limit HB influx through the cotransport system.
MATERNAL PSYCHOLOGICAL STRESS AFTER PRENATAL DIAGNOSIS OF CONGENITAL HEART DISEASE

Prenatal diagnosis of congenital heart disease (CHD) may be beneficial in many ways but it can also increase maternal stress, which may negatively impact both maternal and fetal well-being. Our study objective is to characterize the type and degree of maternal stress incurred by prenatal diagnosis
Respiratory response to baroreceptor stimulation and spontaneous contractions of the urinary bladder.

Abstract Spontaneous contractions of the urinary bladder (SBCs) and experimental elevations of carotid sinus pressure (CSP) have been shown to result in respiratory inhibition with preferential reduction in hypoglossal (HG) nerve activity as compared with that of phrenic nerve discharge. We assessed the interaction between these respiratory inhibitory stimuli in decerebrate, vagotomized, paralyzed and artificially ventilated cats. We denervated the right carotid sinus and pressurized the isolated left carotid sinus region within the linear range of the baroreflex, while maintaining systemic arterial pressure at ∼100 mmHg. We monitored the HG and phrenic nerve responses to SBCs, to elevations in CSP between SBCs, and to elevations in CSP during SBCs. Our results show that superimposing these stimuli results in respiratory inhibition, especially of HG activity, that exceeds that resultant from either stimulus alone. We speculate that the combined presence of SBCs and episodic hypertension may contribute to the development of periodic breathing or obstructive apnea, particularly during sleep.
Quantitative methods for structural characterization of proteins based on deep UV resonance Raman spectroscopy

Here we report on novel quantitative approaches for protein structural characterization using deep UV resonance Raman (DUVRR) spectroscopy. Specifically, we propose a new method combining hydrogen-deuterium (HD) exchange and Bayesian source separation for extracting the DUVRR signatures of various structural elements of aggregated proteins including the cross-beta core and unordered parts of amyloid fibrils. The proposed method is demonstrated using the set of DUVRR spectra of hen egg white lysozyme acquired at various stages of HD exchange. Prior information about the concentration matrix and the spectral features of the individual components was incorporated into the Bayesian equation to eliminate the ill-conditioning of the problem caused by 100% correlation of the concentration profiles of protonated and deuterated species. Secondary structure fractions obtained by partial least squares (PLS) and least squares support vector machines (LS-SVMs) were used as the initial guess for the Bayessian source separation. Advantages of the PLS and LS-SVMs methods over the classical least squares calibration (CLSC) are discussed and illustrated using the DUVRR data of the prion protein in its native and aggregated forms.
Biological sex and menstrual cycle phase modulation of cortisol levels and psychiatric symptoms in a non-clinical sample of young adults

Prior research examined the complex, bidirectional interplay of the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal axes and their roles in (clinical) cognitive/behavioral functions. Less well understood are contemporaneous relationships in non-clinical samples. This pilot study explored cortisol in relation to psychiatric symptoms/personality as a function of self-reported menstrual cycle phase and sex differences in a non-clinical, young adult sample. Consistent with literature and hypotheses, cortisol levels were lowest during early-follicular, intermediary during late-follicular, and highest during mid-luteal phases (not significant), and greater among males than early-follicular females. An acute stressor uniformly affected cortisol across phases and sex, though magnitude and time course differed. Psychiatric symptoms were greater among early-follicular/late-follicular females versus males, and early-follicular and/or late-follicular versus mid-luteal. Contrary to hypotheses, positive psychotic-like symptoms were greater among males than (mid-luteal) females. Cortisol inversely related to early-follicular symptoms, and directly related to late-follicular/mid-luteal symptoms. Results suggest menstrual cycle phase modulates non-clinical psychiatric symptomatology and HPA activity. Findings tentatively bolster a dimensional/continuum model of psychopathology with implications for understanding neurobiological underpinnings and risk/protective factors for mental/physical health conditions, particularly those marked by sex differences and neuroendocrine dysfunction (depression/schizophrenia/Alzheimer's/multiple sclerosis). We speculate a dose-response cortisol effect on symptoms, modulated by endogenous gonadal hormones via gene expression.
Positive parental praise: increasing reactivity and accuracy of self-observation.

The parents of a 6-year-old disruptive boy were observed interacting with their son during 20 assessment-oriented, 10- minute experimental sessions. An experimental design consisting of alternately arranged baseline and self-monitoring conditions was utilized. Following the reversal- to- baseline phase, parents were given specialized training in self-recording positive parental praise. Results indicated that (a) self-monitoring of positive verbalizations was an effective means of producing reactive changes in parental behavior, and (b) training in self-monitoring increased parent-observer accuracy scores to more than acceptable levels of agreement. These findings were discussed with regard to the simplicity of a parental self-observational intervention and recommendations were made for continuing investigations in the area.
Dissolved gas saturation anomalies and excess helium in the ocean

Abstract New solubility measurements have been made for helium and neon in seawater; the results (published elsewhere) show that neon is actually supersaturated in the ocean, rather than generally undersaturated as indicated by previous data. The pattern of He-Ne-Ar saturation anomalies, based on the new solubility data, shows the presence of an injected “atmospheric component” in Atlantic surface and deep waters and in Pacific deep waters, ranging from 0.5 to 1 ml of air (STP)/kg seawater. Nitrogen-argon relationships in the deep Pacific are also consistent with this effect. In addition to T and P, a third parameter is thus required for the study of saturation anomalies. The magnitude of the injected air fraction accounts for all of the “excess He” in Atlantic Deep Water and about 60% of the excess in the Pacific. The non-atmospheric excess He in the Pacific corresponds to an anomaly of 3%, presumably radiogenic and primordial helium.
Semiclassical theory of alignment effects in near-resonant energy-transfer collisions of rare-gas atoms with aligned Rydberg atoms

Recent experiments @E. M. Spain et al., J. Chem. Phys 102, 24 ~1995!# discovered alignment effects in cross sections for near-resonant energy-transfer collisions of Xe atoms with Ca Rydberg atoms at a single mean relative velocity. A collaborative quantum-mechanical study @W. Isaacs and M. A. Morrison, Phys. Rev. A 57, R9 ~1998!# confirmed these findings and discovered pronounced oscillations in the velocity dependence of state-to-state cross sections. Collisions corresponding to the 17dm0→18pm transitions in the Ca-He system are here analyzed semiclassically. This analysis shows that the origin of these oscillations is a phase interference process unique to Rydberg target states. We further demonstrate the importance of retaining the energy defect and of using quantum-defect phase-shifted radial functions in calculations of alignment cross sections for Rydberg states.
Lethal candidiasis in the rat: effects on metabolism and hepatic oxygen supply.

Abstract Previous studies have shown that hepatic entrapment of bloodborne organisms, e.g., bacteria, may result in deleterious reduction of hepatic oxygen supply and disturbances of metabolism within a few hours of challenge. The object of this investigation was to record the effect of Candida albicans since it also is rapidly trapped in liver sinusoids. Rats administered 107 organisms intravenously cleared >99% of the yeast cells within 1 hr, with heavy localization in the liver, among other organs. Mortality was 100% within 30 hr. During the initial 6-hr postchallenge, arterial pressure and gases, hematocrit, and plasma glucose and lactate did not differ from those of saline-injected controls. Hepatic PO2, measured at 6 hr by multiple platinum electrodes, was also similar (mean 19.8 mm Hg in the Candida group, 19.0 Hg in the controls). In overnight survivors of the infected group, however, hepatic PO2 was significantly depressed (mean 10.3 mm Hg compared to 18.4 mm Hg in controls) concomitant to symptoms of circulatory shock. Unlike the effects of various bacteria, no embarrassment of hepatic oxygen supply or disturbance of metabolism was recorded during the course of the lethal candidiasis until systemic circulatory collapse was evident.
Modified dynamic inversion to control large flexible aircraft - What's going on?

High performance aircraft of the future will be designed lighter, more maneuverable, and operate over an ever expanding flight envelope. One of the largest differences from the flight control perspective between current and future advanced aircraft is elasticity. Over the last decade, dynamic inversion methodology has gained considerable popularity in application to highly maneuverable fighter aircraft, which were treated as rigid vehicles. This paper explores dynamic inversion application to an advanced highly flexible aircraft. An initial application has been made to a large flexible supersonic aircraft. In the course of controller design for this advanced vehicle, modifications were made to the standard dynamic inversion methodology. The results of this application were deemed rather promising. An analytical study has been undertaken to better understand the nature of the made modifications and to determine its general applicability. This paper presents the results of this initial analytical look at the modifications to dynamic inversion to control large flexible aircraft.
The role of ultrasound-indicated cerclage in triplets.

Objectives Preterm delivery is the leading cause of major perinatal morbidity and mortality associated with triplet pregnancies. The objective of this study was to evaluate the efficacy of ultrasound-indicated cervical cerclage in triplet pregnancies that are diagnosed with cervical shortening on biweekly transvaginal sonography (TVS). Methods A retrospective review of all triplets who were followed with biweekly TVS for measurement of cervical length was conducted. Cervical shortening was defined as cervical length ⩽ 2.5 cm. Outcomes of interest included cervical cerclage placement, gestational age at delivery and birth weight. Results In our population of 24 triplet pregnancies, 13 had cervical shortening. Of these, 54% underwent cervical cerclage at a mean gestational age of 20 weeks. Overall, patients without cervical shortening delivered on average 17 days later than those with cervical shortening (32 + 2 weeks vs. 29 + 6 weeks, P = 0.034). Moreover, infants of patients without cervical shortening weighed on average 456 g more at birth than did those with cervical shortening (1751 g vs. 1295 g, P = 0.039) and had a lower percentage of very low birth weight infants (30.3% vs. 69.2%, P = 0.002). Within the subset of patients with cervical shortening, there was no statistical difference in any of the outcomes studied between patients who underwent cervical cerclage and those who did not. Conclusions Triplet pregnancies complicated by cervical shortening diagnosed on biweekly TVS surveillance do not appear to benefit from placement of cervical cerclage, based on assessment of gestational age at delivery, birth weight and incidence of very low birth weight infants. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
Doped ZnO thin films as anode materials for organic light-emitting diodes

Zinc oxide thin films, doped with aluminum (AZO), gallium (GZO) and zirconium (ZZO), have been deposited on glass substrates by pulsed laser deposition. The electrical and optical properties of these films were investigated as a function of oxygen deposition pressure. These doped zinc oxide films were used as an anode contact to fabricate organic light-emitting diodes. Luminance efficiencies of 0.1 lm/W, 0.2 lm/W and 0.9 lm/W were measured at the light output of 100 cd/m2 for the AZO, GZO and ZZO films, respectively. Doped zinc oxides are attractive alternative materials as transparent conducting electrode because they are nontoxic and inexpensive compared with indium tin oxide (ITO).
A top management computer

A computerized comprehensive management tracking system for the President of the United States was created. The technical and political problems of implementing the system are recounted. This study applies to decision processes at the organization level.
Wide Field and Planetary Camera for Space Telescope

The Space Telescope's Wide Field and Planetary Camera instrument, presently under construction, will be used to map the observable universe and to study the outer planets. It will be able to see 1000 times farther than any previously employed instrument. The Wide Field system will be located in a radial bay, receiving its signals via a pick-off mirror centered on the optical axis of the telescope assembly. The external thermal radiator employed by the instrument for cooling will be part of the exterior surface of the Space Telescope. In addition to having a larger (1200-12,000 A) wavelength range than any of the other Space Telescope instruments, its data rate, at 1 Mb/sec, exceeds that of the other instruments. Attention is given to the operating modes and projected performance levels of the Wide Field Camera and Planetary Camera.
A Process Similar to Autophagy Is Associated with Cytocidal Chloroquine Resistance in Plasmodium falciparum

Resistance to the cytostatic activity of the antimalarial drug chloroquine (CQ) is becoming well understood, however, resistance to cytocidal effects of CQ is largely unexplored. We find that PfCRT mutations that almost fully recapitulate P. falciparum cytostatic CQ resistance (CQR(CS)) as quantified by CQ IC50 shift, account for only 10-20% of cytocidal CQR (CQR(CC)) as quantified by CQ LD50 shift. Quantitative trait loci (QTL) analysis of the progeny of a chloroquine sensitive (CQS; strain HB3)×chloroquine resistant (CQR; strain Dd2) genetic cross identifies distinct genetic architectures for CQR(CS) vs CQR(CC) phenotypes, including identification of novel interacting chromosomal loci that influence CQ LD50. Candidate genes in these loci are consistent with a role for autophagy in CQR(CC), leading us to directly examine the autophagy pathway in intraerythrocytic CQR parasites. Indirect immunofluorescence of RBC infected with synchronized CQS vs CQR trophozoite stage parasites reveals differences in the distribution of the autophagy marker protein PfATG8 coinciding with CQR(CC). Taken together, the data show that an unusual autophagy-like process is either activated or inhibited for intraerythrocytic trophozoite parasites at LD50 doses (but not IC50 doses) of CQ, that the pathway is altered in CQR P. falciparum, and that it may contribute along with mutations in PfCRT to confer the CQR(CC) phenotype.
Targeting the Wnt pathway in human cancers: therapeutic targeting with a focus on OMP-54F28

The Wnt signaling pathways are a group of signal transduction pathways that play an important role in cell fate specification, cell proliferation and cell migration. Aberrant signaling in these pathways has been implicated in the development and progression of multiple cancers by allowing increased proliferation, angiogenesis, survival and metastasis. Activation of the Wnt pathway also contributes to the tumorigenicity of cancer stem cells (CSCs). Therefore, inhibiting this pathway has been a recent focus of cancer research with multiple targetable candidates in development. OMP-54F28 is a fusion protein that combines the cysteine-rich domain of frizzled family receptor 8 (Fzd8) with the immunoglobulin Fc domain that competes with the native Fzd8 receptor for its ligands and antagonizes Wnt signaling. Preclinical models with OMP-54F28 have shown reduced tumor growth and decreased CSC frequency as a single agent and in combination with other chemotherapeutic agents. Due to these findings, a phase 1a study is nearing completion with OMP-54F28 in advanced solid tumors and 3 phase 1b studies have been opened with OMP-54F28 in combination with standard-of-care chemotherapy backbones in ovarian, pancreatic and hepatocellular cancers. This article will review the Wnt signaling pathway, preclinical data on OMP-54F28 and other Wnt pathway inhibitors and ongoing clinical trials.
Prevention of Pneumocystis carinii Pneumonia

Prophylaxis against Pneumocystis carinii pneumonia is a logical management strategy for patient populations that have a high incidence of this infectious complication. Appropriate populations for consideration would include those with human immunodeficiency virus infection, recent recipients of bone marrow or solid organ transplants. children with acute lymphocytic leukemia, and adults with T cell leukemias
Interactive cell modeling web-resource, iCell, as a simulation-based teaching and learning tool to supplement electrophysiology education.

An interactive cell modeling web site, iCell ( http://ssd1.bme.memphis.edu/icell/ ), that integrates research and education, was developed to present and to disseminate JAVA-coded models of cellular activities, and to supplement physiology education. iCell can be used to supplement the text-book material as a simulation-based teaching and learning tool. Specifically, iCell allows the students to supplement their learning experiences of the text-book cellular physiology material by running simulations in an interactive environment. The site consists of JAVA-coded models of various cardiac cells and neurons, and provides simulation data of their bioelectric transport activities at cellular level. Each JAVA-coded model allows the user to go through menu options to change model parameters, run and view simulation results. The site also has a glossary section for the scientific terms. iCell has been used as a teaching and learning tool for seven graduate courses at the Joint Biomedical Engineering Program of University of Memphis and University of Tennessee. This modeling tool was also used as a collaboration site among our physiology colleagues interested in simulations of cell membrane activities. Scientists from the fields of biosciences, engineering, life sciences and medical sciences in 17 countries have tested and utilized iCell as a simulation-based teaching, learning and collaboration environment. iCell provides us with an interactive, platform-independent, and user-friendly teaching and learning resource, and also a collaboration environment for electrophysiology to be shared over the Internet. The usage of simulations for teaching and learning will continue advancing simulation-based engineering and sciences for research and development.
Peers' Rejection as a Possible Consequence of Official Reaction to Delinquency in Chinese Society

Drawing on labeling theory, this study examined peers' attitudinal responses to the official label of delinquency. Specifically, two questions were asked: (a) Do peers' attitudinal responses to official delinquents vary with the severity of official reaction? (b) Do peers' attitudinal responses depend on their own labeling status? Questions concerning hypothetical delinquents receiving differing levels of severity of official reaction were administered to delinquents and nondelinquents in Tianjin, China. The severity of official reaction to delinquency was significantly associated with peers' rejection of official delinquents, with this relationship being greater for nondelinquent peers' rejection than for delinquent peers' rejection. Also, peers' attitudinal rejection varied significantly with their own labeling status, but only at certain levels of severity of official reaction. The findings were generally consistent with the labeling perspective. Discussion focuses on their implications for theory and ...
Energy spectra of donors in GaAs-Ga1−xAlxAs quantum well structures

Abstract We present the results of a theoretical study of the variation of the binding energy for shallow donor states in quantum well structures consisting of a single slab of GaAs sandwiched between two semi-infinite slabs of Ga 1− x Al x As . The alloy composition, x , is varied between 0.1 and 0.4. In this range, the Ga 1− x Al x As is direct and the single-valley effective mass theory is a valid technique for treating shallow states. Calculations are carried out in the case of finite potential barrier determined by realistic conduction band offsets. We find that the binding energy varies from about 5 meV at infinite GaAs slab thickness to a maximum value between 15 and 5 monolayers depending on the alloy composition. The maximum binding energy varies from about 12 meV for the x = 0.1 alloy to about 16 mcV for the x = 0.4 alloy
Lymphoid changes during antibody synthesis in larval Rana catesbeiana.

Thymectomy, splenectomy and/or lymphadenctomy affect antibody synthesis to a soluble antigen, hemocyanin, in bullfrog larvae. Tadpoles were divided into seven groups and these into three subgroups: Experimentals— A: operated and immunized by hemocyanin or allografts; Controls—B: operated but non-immunized; Controls—C: one group unoperated and immunized. With regard to the spleen, good correlation between antibody titer and degree of splenic regeneration was observed. Structurally, the white pulp contained numerous small lymphocytes but in the red pulp, the number of blast cells and lymphocytes increased. The spleen may be the main organ involved in larval antibody synthesis. The lymph glands seem secondary; lymphadenectomized larvae showed no regeneration of lymph glands and antibody titers were lower than in sham-operated controls. Compensatory hypertrophy of the remaining gland in unilaterally lymphadenectomized larvae was absent. With regard to cell types, lymph glands showed a picture similar to active nodules, i.e., the core of the cords consisted of blast cells and larger lymphocytes surrounded by layers of small lymphocytes. Thymic regeneration occurred in all tadpoles and, of much interest, titers were always highest in this previously thymectomized group. Observations on thymectomized tadpoles suggest a thymus stimulating effect on certain peripheral lymphoid organs, notably the spleen. The thymus in frog larvae may be important in antibody synthesis during later stages when the capacity to develop cellular immunity has already matured.
Anatomy of a physics test: Validation of the physics items on the Texas Assessment of Knowledge and Skills

We report the results of an analysis of the Texas Assessment of Knowledge and Skills (TAKS) designed to determine whether the TAKS is a valid indicator of whether students know and can do physics at the level necessary for success in future coursework, STEM careers, and life in a technological society. We categorized science items from the 2003 and 2004 10th and 11th grade TAKS by content area(s) covered, knowledge and skills required to select the correct answer, and overall quality. We also analyzed a 5000 student sample of item-level results from the 2004 11th grade exam, performing full-information factor analysis, calculating classical test indices, and determining each item's response curve using item response theory. Triangulation of our results revealed strengths and weaknesses of the different methods of analysis. The TAKS was found to be only weakly indicative of physics preparation and we make recommendations for increasing the validity of standardized physics testing.
Reactions of electrons in high-concentration water solutions—A comparison between pulse-radiolysis and positron annihilation lifetime spectroscopy data

Abstract A comparison of pulse radiolysis and positron annihilation lifetime data shows that there is a very good correlation between 1/C37 and kpi, the positronium formation inhibition constant. This correlation is much better than that between kpi and k(e-aq+S), suggesting that a large fraction of positronium is formed by the reaction of the positron with precursors of e-aq. The reaction rate of a charged solute (S) with the hydrated electron, k(e-aq+S) is not always correlated with the ability to scavenge the precursors of e-aq measured through the C37 constant.
Brain-Derived Neurotrophic Factor in the Airways

In addition to their well-known roles in the nervous system, there is increasing recognition that neurotrophins such as brain derived neurotrophic factor (BDNF) as well as their receptors are expressed in peripheral tissues including the lung, and can thus potentially contribute to both normal physiology and pathophysiology of several diseases. The relevance of this family of growth factors lies in emerging clinical data indicating altered neurotrophin levels and function in a range of diseases including neonatal and adult asthma, sinusitis, influenza, and lung cancer. The current review focuses on 1) the importance of BDNF expression and signaling mechanisms in early airway and lung development, critical to both normal neonatal lung function and also its disruption in prematurity and insults such as inflammation and infection; 2) how BDNF, potentially derived from airway nerves modulate neurogenic control of airway tone, a key aspect of airway reflexes as well as dysfunctional responses to allergic inflammation; 3) the emerging idea that local BDNF production by resident airway cells such as epithelium and airway smooth muscle can contribute to normal airway structure and function, and to airway hyperreactivity and remodeling in diseases such as asthma. Furthermore, given its pleiotropic effects in the airway, BDNF may be a novel and appealing therapeutic target.
Clinical experience with antithrombin III concentrate in treatment of congenital and acquired deficiency of antithrombin

Phase I clinical studies of antithrombin III (ATIII) concentrate demonstrated a mean in vivo incremental recovery of functional activity of 1.4 percent per unit/kg administered, an initial 50 percent disappearance time of 22 hours, and a biologic half-life of 3.8 days. Based on these observations, a treatment regimen designed to maintain plasma ATIII levels between 75 and 120 percent of normal has been developed. None of 10 subjects with congenital ATIII deficiency treated prophylactically had evidence of thromboembolism, including four pregnant women at the time of delivery. Five subjects treated for acute thrombosis and/or thromboembolism, four of whom were pregnant, recovered without further thrombotic extension or recurrence. Heparin resistance was reversed in two subjects, both pregnant. Nine subjects with acquired ATIII deficiency also received ATIII treatment for venous or arterial thrombosis or disseminated intravascular coagulation, all with low plasma ATIII levels. Two subjects with disseminated intravascular coagulation demonstrated improvement, one clinically, the other biochemically. All patients with congenital ATIII deficiency survived, but only five of nine with acquired deficiency survived, highlighting the importance in acquired ATIII deficiency of the underlying disease in prognosis. Survival rate was especially poor in subjects with arterial thrombosis in the setting of low plasma ATIII. Administration of ATIII concentrate was well tolerated. None of the subjects who received ATIII concentrate demonstrated evidence of an infectious transmissible agent. These studies demonstrate that it is now feasible to safely replace the deficient protein in congenital ATIII deficiency, either prophylactically or therapeutically.
Cystic Lesions of the Pancreas

Because of better imaging resolution and increased use of abdominal radiologic studies in the aging population, cystic pancreatic lesions are now commonly detected 1-4 and are most frequently incidental. Other factors, such as optimization of the timing of contrast agent injection and multiphasic image acquisition, also have contributed to improved detection. 5 Asopposedtotheolderdictumsthatnearlyallcystic lesions in the pancreas are postinflammatory pseudocysts, or that all patients (asymptomatic as well as symptomatic) with cystic masses who are “good” surgical candidates should undergo resection, 2 newer observations and strategies for management of patients with cystic pancreatic masses must be considered, especially when the lesions are incidental. In 2001, Megibow was one of the first to suggest that in select patients, imaging surveillance might be possible if lesions are small, spare the main pancreatic duct, and demonstrate no solid components. 6 That concept has been further refined and supported by others to include that if the lesion is thoughttobebenignorlowgradeonthebasisofimagingand analysis of cyst fluid obtained by fine needle aspiration (FNA), most can be managed conservatively with surveillance imaging. 2-4,7,8 After describing and demonstrating the typical demographic and imaging features of cystic pancreatic lesions, this review will discuss newer guidelines for selection of patients suitable for surgical treatment. Although there is yet no consensus, follow-up imaging strategies and intervals for surveillance will be discussed.
Long-Distance Migration and Colonization of Transplanted Neural Stem Cells

A recent study reported remarkable survival and exuberant axon outgrowth from transplants of neural stem cells (NSCs) in a fibrin matrix with growth factors that were grafted into a complete spinal cord transection site in rats (Lu et al., 2012). As part of the NIH-supported replication project (Facilities of Research Excellence-Spinal Cord Injury), we repeated key parts of that study. Because this is a surgical intervention that may depend on skills that require extensive experience, we felt that the goals of the replication would be best served if the same surgeon performed the lesion surgeries and transplants.
Effects of deformable registration algorithms on the creation of statistical maps for preoperative targeting in deep brain stimulation procedures

Deep brain stimulation, which is used to treat various neurological disorders, involves implanting a permanent electrode into precise targets deep in the brain. Accurate pre-operative localization of the targets on pre-operative MRI sequence is challenging as these are typically located in homogenous regions with poor contrast. Population-based statistical atlases can assist with this process. Such atlases are created by acquiring the location of efficacious regions from numerous subjects and projecting them onto a common reference image volume using some normalization method. In previous work, we presented results concluding that non-rigid registration provided the best result for such normalization. However, this process could be biased by the choice of the reference image and/or registration approach. In this paper, we have qualitatively and quantitatively compared the performance of six recognized deformable registration methods at normalizing such data in poor contrasted regions onto three different reference volumes using a unique set of data from 100 patients. We study various metrics designed to measure the centroid, spread, and shape of the normalized data. This study leads to a total of 1800 deformable registrations and results show that statistical atlases constructed using different deformable registration methods share comparable centroids and spreads with marginal differences in their shape. Among the six methods being studied, Diffeomorphic Demons produces the largest spreads and centroids that are the furthest apart from the others in general. Among the three atlases, one atlas consistently outperforms the other two with smaller spreads for each algorithm. However, none of the differences in the spreads were found to be statistically significant, across different algorithms or across different atlases.
Adenosine receptor binding: Structure-activity analysis generates extremely potent xanthine antagonists

Structure-activity analysis of alkylxanthine derivatives at adenosine receptor binding sites has been employed to design more potent adenosine receptor antagonists. Receptor affinities of xanthines were determined by measuring inhibition of the binding of N6-[3H]cyclohexyladenosine to bovine brain membranes. 1,3-Dipropyl substitutions enhance potency compared to the 1,3-dimethyl substitution in theophylline. An 8-phenyl substituent produces a considerable increase in potency, which is augmented by certain para substitutions on the 8-phenyl ring. Combining an ortho amino with a para-chloro substituent on the 8-phenyl ring affords further increases in potency. Combining all of these substituents results in 1,3-dipropyl-8-(2-amino-4-chlorophenyl) xanthine, a compound of extraordinary receptor affinity, with a Ki for adenosine A1 receptors of 22 pM. It is 4,000,000 times more potent than xanthine itself and 70,000 times more potent than theophylline.
Peptidyl-transfer RNA hydrolase prevents inhibition of protein synthesis initiation.

PEPTIDYL-tRNA HYDROLASE (called hydrolase below) catalyses the hydrolysis of peptides from peptidyl-tRNAs that are not bound to ribosomes1,2 but will not hydrolyse amino acyl-tRNA or fMet-tRNAfMet. It is interesting that hydrolase seems to be ubiquitous in nature, it has been found in all cells where it has been sought, including yeast3, bacteria, rat liver and jackbeans4 However, the metabolic role of this enzyme has not been established It is required for normal function, as a mutant strain of Escherichia coli with a temperature-sensitive hydrolase cannot continue protein synthesis at the nonpermissive temperature5 Hydrolase itself is not required for initiation, elongation or termination phases of protein synthesis6 Menninger7 has shown that peptidyl-tRNA, formed on ribosomes, accumulates at nonpermissive temperatures in cells with the temperature-sensitive hydrolase. Hydrolase thus seems to be a scavenger enzyme of peptidyl-tRNAs normally aborted from ribosomes during protein synthesis Of interest now is why peptidyl-tRNA is frequently prematurely released from ribosomes and why protein synthesis is inhibited in the mutant strain with a defective hydrolase5 I report here work on the latter problem and present evidence which indicates that peptidyl-tRNAs accumulate and compete with N-formal-Met tRNAfMet during initiation of protein synthesis.
Regional Gravity Anomalies in Central California: ABSTRACT

A Bouguer gravity map of central California east of the Coast Ranges has been compiled from over 11,000 observations made by the U. S. Geological Survey, the U. S. Naval Ordnance Test Station, and several oil companies. The Bouguer reductions are based on a rock density of 2.67 g/cm3 and include terrane corrections in all mountainous areas. Regional gravity lows in the west and south parts of the San Joaquin Valley are produced by a maximum estimated thickness of more than 30,000 feet of Upper Cretaceous and Cenozoic deposits. Gravity lows also occur over local basins south and east of the Sierra Nevada which, in conjunction with limited seismic refraction measurements, indicate the following maximum thicknesses of Cenozoic deposits: Mono Basin and Long Valley--18,000 feet; Death Valley and Cantil Valley--10,000 feet; Owens Valley--9,000 feet; Indian Wells Valley--8,000 feet; Searles Basin, Saline Valley, and Panamint Valley--3,500 feet. Bouguer gravity values corrected for the effect of the Upper Cretaceous and Cenozoic deposits show a broad, asymmetrical gravity low centered over the eastern Sierra Nevada with the steepest gradients and greatest relief on the west side. This major anomaly disturbs the earth's gravity field from the western San Joaquin Valley to the California-Nevada border. It can be explained by isostatic compensation of the Sierra Nevada and high areas to the east plus the relatively low-density rocks of the Sierra Nevada batholith. A gravity ridge that extends for several hundred miles along the east side of the San Joaquin Valley shows excellent correlation with a similar magnetic ridge, suggesting that both anomalies are caused by a dense, magnetic mass buried at an estimated depth of 5-10 miles. This depth approaches the approximate 12 mile thickness of the earth's crust under the valley indicated by seismic refraction measurements. End_of_Article - Last_Page 1774------------
A study of accepted pricing points for in‐room entertainment technology amenities by guests

Purpose – In‐room entertainment technology continues to evolve in the hotel industry. However, given the multitude of entertainment products available in the market place today, hoteliers have little clarity of guests' willingness to pay for those in‐room entertainment technology amenities. In this highly competitive environment for travelers, lodging managers should better understand what in‐room entertainment technology amenities their guests will purchase. The purpose of this study is to explore accepted pricing levels for in‐room entertainment technology amenities by hotel guests.Design/methodology/approach – A sample of 2,500 US travelers was drawn randomly from a national database by rent‐a‐list.com for this study. An online survey was distributed. The response rate was 16.32 percent with 408 respondents.Findings – Findings showed that guests want most of the in‐room entertainment technology amenities as complimentary. However, they are willing to pay for gaming consoles in their guest rooms.Origina...
Condyloma and Other Infections Including Human Immunodeficiency Virus

Sexually transmitted diseases (STDs) are a common public health problem and as such may be more common in a surgical practice than is believed. The recognition that a virus can be responsible for a cancer has profound significant public health implications. This article reviews the presentation and management of the more common perianal STDs including human immunodeficiency virus, as well as the pathogenesis and management of anal intraepithelial neoplasia.
Activins and Inhibins and Their Signaling

Activins and inhibins, which were discovered by virtue of their abilities to stimulate or inhibit, respectively, the secretion of FSH, are members of the transforming growth factor-beta (TGFbeta) superfamily and exert a broad range of effects on the diffentiation, proliferation and functions of numerous cell types. Activins interact with two structurally related classes of serine/threonine kinase receptors (type I and type II). Inhibin antagonizes activin by binding to the proteoglycan, betaglycan, and forming a stable complex with and, thereby, sequestering type II activin receptors while excluding type I receptors. If betaglycan is present, inhibin can also antagonize those bone morphogenic proteins (BMPs) whose signaling is dependent upon access to type II activin receptors. Recent insights regarding the structures of ligands, receptors and their signaling complexes are providing the basis for the development of therapeutics capable of modulating fertility and numerous pathophysiologic processes.