cssi/SciSciGPT-SciSciNet huggingface dataset:
Thymidine and Thymine Incorporation into Deoxyribonucleic Acid: Inhibition and Repression by Uridine of Thymidine Phosphorylase of Escherichia coli

Thymidine is poorly incorporated into deoxyribonucleic acid (DNA) of Escherichia coli. Its incorporation is greatly increased by uridine, which acts in two ways. Primarily, uridine competitively inhibits thymidine phosphorylase (E.C.2.4.4), and thereby prevents the degradation of thymidine to thymine which is not incorporated into normally growing E. coli. Uridine also inhibits induction of the enzyme by thymidine. It prevents the actual inducer, probably a deoxyribose phosphate, from being formed rather than competing for a site on the repressor. The inhibition of thymidine phosphorylase by uridine also accounts for inhibition by uracil compounds of thymine incorporation into thymine-requiring mutants. Deoxyadenosine also increases the incorporation of thymidine, by competitively inhibiting thymidine phosphorylase. Deoxyadenosine induces the enzyme, in contrast to uridine. But this is offset by a transfer of deoxyribose from deoxyadenosine to thymine. Thus, deoxyadenosine permits incorporation of thymine into DNA, even in cells induced for thymidine phosphorylase. This incorporation of thymine in the presence of deoxyadenosine did not occur in a thymidine phosphorylase-negative mutant; thus, the utilization of thymine seems to proceed by way of thymidine phosphorylase, followed by thymidine kinase. These results are consistent with the data of others in suggesting that wild-type E. coli cells fail to utilize thymine because they lack a pool of deoxyribose phosphates, the latter being necessary for conversion of thymine to thymidine by thymidine phosphorylase.
Update on optical component reliability and testing requirements

Optical component reliability, as underway in international standards, is reviewed. In optical communications, the reliability functions of fiber and optoelectronic semiconductor transceivers, has been extensively studied and modeled for some time. The mechanisms causing failure for these are relatively well known. The mechanisms in other items such as passive optical components, optical amplifiers, or dynamic components (that are optically passive but electrically active) are not nearly as well understood.
Synthesis, Characterization and Hall Effect Measurements of Nanocrystalline ZnO Thin Films

ZnO thin films were prepared by sol-gel method. Prepared thin films were then characterized by SEM, XRD, EDX and Hall effect measurements. SEM confirmed the morphological studies of ZnO thin films. Crystallite size is calculated using the Scherrer formula. Crystallite and grain sizes are obtained through XRD and SEM. EDS analysis confirms mass percentage of ZnO deposited. Decreasing trend of magneto resistance with temperature is observed. The optical transmission spectra of the solgel deposited ZnO thin films showed high transmittance (>70%) in the visible region and indicates that the transmittance of ZnO films gradually decreased as the thickness increased. Decreasing trend of resistivity and sheet resistance with thickness are also observed. The IV characterization of ZnO thin films under influence of UV and dark conditions are reported. The dc electrical resistivity data follow the hoping model.
Cadmium and arsenite binding byN-dihydrolipoyl-aminoethoxydextran: A model study of enzyme dithiol criteria

Abstract We have observed the interaction of Cd 2+ , Zn 2+ , and AsO 2 2− with a dithiol-substituted polymer ( N -dihydrolipoyl aminoethoxy dextran). Cadmium binding results in an intense uv difference spectrum (λ max = 240 nm). Spectrophotometric titrations with CdCl 2 reveal formation of two Cd-dithiol complexes characterized as 2—SH/Cd 2+ and 3—SH/Cd 2+ . Stability constants were determined by titration of cadmium-saturated polymer with excess EDTA. For the two complexes, K 1 = 2.7 × 10 14 M and K 2 = 7.7 × 10 13 M . NTA is not effective in displacing Cd 2+ . In competition of Cd 2+ and Zn 2+ for dithiol sites, Cd 2+ is bound about 500 times more firmly than Zn 2+ . Arsenite binding is sluggish ( K ∼ 85 M −1 sec −1 ) and yields a single complex (2—SH/AsO 2 2− ). Competition and kinetic data suggest that 10 6 M K AsO 2 − 2 M . We have defined basic criteria for evaluation of enzyme active-site dithiols: (1) the binding order “cadmium stronger than zinc”; (2) relief of Cd 2+ inhibition by 10-fold excess EDTA and no relief by 10-fold excess of NTA; (3) inhibition by arsenite.
Metabolic control of regulatory T cell development and function.

Foxp3+ regulatory T cells (Tregs) maintain immune tolerance and play an important role in immunological diseases and cancers. Recent studies have revealed an intricate relationship between Treg biology and host and microbial metabolism. Various metabolites or nutrients produced by host and commensal microbes, such as vitamins and short-chain fatty acids (SCFAs), regulate Treg generation, trafficking, and function. Furthermore, cell intrinsic metabolic programs, orchestrated by mTOR and other metabolic sensors, modulate Foxp3 induction and Treg suppressive activity. Conversely, Tregs are crucial in regulating obesity-associated inflammation and host metabolic balance, and in shaping homeostasis of gut microbiota. We review here the interplay between Tregs and metabolism, with a particular focus on how host, commensal, and cellular metabolism impinge upon Treg homeostasis and function.
Ferromagnetic micromechanical magnetometer

A novel micromechanical magnetometer has been designed, fabricated, and tested that consists of low-stress electrodeposited hard magnetic alloys and surface micromachined polysilicon structures. The sensor responds to applied magnetic fields without consuming any power and the magnitude of the response is scale independent. By optically measuring their response, these second-generation sensors can be used to detect fields as small as 500 nT and their experimental performance agree well with theoretical predictions.
Chloral hydrate inhibits protein synthesis in vivo.

A wide variety of substances can produce the unique inhibition of cell division characterized as c-mitosis and can also induce anesthesia. One of these is chloral hydrate. It is more active, on the basis of its physical properties, than other compounds with the same effects. We investigated the basis of its unique effectiveness for the inhibition of cell division using the protozoan, Chlamydomonas reinhardii. At a concentration which inhibits cell division, it completely inhibits protein synthesis in vivo, but has only slight effects on a number of other cellular functions. This inhibition is sufficient to explain its inhibition of cell division. In addition it is possible that this inhibition of protein synthesis by chloral hydrate may be relevant to its effects on the central nervous system.
Sequence organization of the poly(A) RNA synthesized and accumulated in lampbrush chromosome stage Xenopus laevis oocytes

The poly(A) RNA of Xenopus laevis oocytes was extracted, renatured and spread for electron microscopy. As reported for the poly(A) RNA of sea urchin eggs (Costantini et al., 1980), the Xenopus oocyte RNA renatures extensively, revealing the presence of complementary, interspersed repetitive sequences on different RNA molecules. About 68% of the mass of the poly(A) RNA in late ovarian oocytes is included in multimolecular structures after renaturation, and a similar fraction of the poly(A) RNA of mid-lampbrush stage oocytes also contains interspersed repeat sequences. In contrast, less than 15% of the poly(A) RNA molecules of stage 41 tadpoles retains the capacity for RNA duplex formation under the same conditions. Poly(A) RNAs displaying interspersed sequence organization are located in the oocyte cytoplasm. This was shown using manually enucleated oocytes. Lampbrush stage oocytes were injected with [3H]GTP, allowed to incorporate for 48 hours, enucleated, and the poly(A) [3H]RNA extracted. The fraction of the labelled poly(A) RNA that could be attributed to mitochondrial transcription was ≤ 16%, according to measurements made with cloned mitochondrial DNA. By use of a cellulose column that separates RNA-containing duplex regions, the labelled RNA was shown to anneal almost completely with the poly(A) RNA already accumulated in the cytoplasm of the oocytes. The newly synthesized poly(A) RNA exported from lampbrush chromosome stage oocyte nuclei also displays an interspersed sequence organization. RNA synthesized in vitro in isolated germinal vesicles was reacted with six cloned complementary DNAs that contain maternal poly(A) RNA sequences, and all of these probes were represented in the transcription products. Thus the amphibian lampbrush chromosome stage oocyte nucleus synthesizes and transports to the cytoplasm poly(A) RNAs that, are similar in structure and sequence content to the maternal poly(A) RNA stored in the oocyte at the termination of oogenesis. We conclude that this poly(A) RXA turns over slowly, thereby maintaining an approximately constant steady state throughout oogenesis. However, the maternal poly(A) RNA pool is so large that the rate of synthesis required for this process demands the intense and widespread level of transcription observed in lampbrush chromosomes.
Effects of Psoralen-Derivatized Oligonucleoside Methylphosphonates on Vesicular Stomatitis Virus (VSV) Protein Synthesis In Vitro and in VSV-Infected Cells †

Abstract Oligodeoxyribonucleoside methylphosphonates (16-mers) targeted to VSV mRNAs were derivatized with 4′-{[N-(aminoethyl)amino]methyl}-4,5′8-trimethylpsoralen. These oligomers specifically inhibit translation of their targeted mRNAs in vitro following UV irradiation of the oligomer-mRNA complexes. Psoralen-derivatized oligonucleoside methylphosphonates are stable in cells and can inhibit VSV protein synthesis in culture following UV-irradiation of VSV-infected cells. †This paper is dedicated to Dr. Yoshihisa Mizuno on the occasion of his 75th birthday.
The effect of solute layering on lateral heat transfer in an enclosure

Abstract The effect of the presence of stable layering of a solute on the heat transfer across an enclosure with differentially heated side walls is studied. The method of investigation employed is the finite difference simulation of the governing conservation equations for laminar free convection. For stable convecting systems, the converting layers are found to behave as individual, low aspect ratio enclosures, with a consequent decrease in lateral heat transfer. The fluid in layered systems which are kinematically unstable upon heating is observed to penetrate the diffusive interface adjacent to heated (or cooled) side walls, leading to rapid mixing of the layers.
The effects of restaurant servers' perceptions of customers' tipping behaviors on service discrimination.

Abstract Scholars have noted that the institution of tipping may encourage restaurant servers to provide discriminate service. The prospect of receiving an excellent tip from a patron, for example, is thought to encourage servers to discriminately provide excellent service. In contrast, the prospect of receiving a poor tip from a patron is thought to encourage servers to extend service that is commensurately poor. The effects of service workers’ a priori assumptions about customers’ tipping behaviors on service discrimination have however not been adequately assessed to-date. This article addresses this gap in the literature by assessing how server sensitivity to demographic tipping differences affects their proclivities to discriminately provide either excellent or poor service in response to the prospect of receiving an excellent or poor tip, respectively. Using a multilevel modeling technique (HLM), findings show that server sensitivity to demographic tipping differences is predictive of servers’ propensities to discriminately allocate excellent service but not poor service. The implications for the management of restaurant operations along with directions for future research are discussed.
Exploring the Impact of Gender Role Self-Perception on Communication Style

In this investigation, communication style was conceptualized as the way individuals perceive themselves interacting with others. Using the Bern Sex Role Inventory (BSRI; Bem, 1976, 1985) and the Communication Styles Profile Test (CSPT; McCallister, 1992), three predominant communication styles were examined as a function of respondent sex and gender role self-perception. Consistent with expectations, the data show that gender role self-perception mediated reported communication style. Independent of sex, the findings revealed that communal respondents prefer a sharing, expressive communication style; whereas agentic respondents prefer a dominating, assertive communication style. Although a less distinctive pattern, significant sex-differences were also evident in communication style preference. Females reported a socially-oriented style of communicating while males reported a more direct, results-oriented communication style. Further, no sex by gender role self-perception interaction was evident. The imp...
Cross sections and energy loss for lepton pair production in muon transport

We reevaluate electron-positron pair production from electromagnetic interactions of muons in transit through materials. Our approach, through the use of structure functions for inelastic and elastic scattering and including hadronic recoil, make the formalism useful for tau pair production at high energies. Our results for electron-positron pairs agree well with prior evaluations. Tau pair production, however, has significant contributions from inelastic scattering in addition to the usual coherent scattering with the nucleus and scattering with atomic electrons.
Insights into phylogeny, sex function and age of Fragaria based on whole chloroplast genome sequencing

Abstract The cultivated strawberry is one of the youngest domesticated plants, developed in France in the 1700s from chance hybridization between two western hemisphere octoploid species. However, little is known about the evolution of the species that gave rise to this important fruit crop. Phylogenetic analysis of chloroplast genome sequences of 21 Fragaria species and subspecies resolves the western North American diploid F. vesca subsp. bracteata as sister to the clade of octoploid/decaploid species. No extant tetraploids or hexaploids are directly involved in the maternal ancestry of the octoploids. There is strong geographic segregation of chloroplast haplotypes in subsp . bracteata , and the gynodioecious Pacific Coast populations are implicated as both the maternal lineage and the source of male-sterility in the octoploid strawberries. Analysis of sexual system evolution in Fragaria provides evidence that the loss of male and female function can follow polyploidization, but does not seem to be associated with loss of self-incompatibility following genome doubling. Character-state mapping provided insight into sexual system evolution and its association with loss of self-incompatibility and genome doubling/merger. Fragaria attained its circumboreal and amphitropical distribution within the past one to four million years and the rise of the octoploid clade is dated at 0.372–2.05 million years ago.
Inexpensive seismic sensors for early warning of military sentries

Small military units operate under stressful conditions with limited resources. A lightweight mobile surveillance system could reduce the effort to conduct sentry duties, and could help prevent ambushes or other types of attacks. We explore the use of built-in sensors and networking abilities of modern "smartphones" to fill this gap. Current smartphones use accelerometers to sense changes in orientation of the phone. This same capability can be used to detect vibrations in the ground produced by approaching footsteps or vehicles. We discuss the sensitivity of the phone, the filtering techniques, and the footstep signatures registered by the phone. We then discuss the possible deployment configurations of single and multiple sensors to create a sensor grid that can be networked together. Key concerns are ground noise, sensitivity of the phone, and distance between networked phones.
Roles and reactivities of antibodies to alphaviruses

Abstract Antibodies to alphaviruses are essential for recovery from infection. These antibodies act by interacting with the E1 and E2 glycoproteins on the virion and on the surface of infected cells. E1 epitopes are displayed primarily on infected cells and are cryptic on the virion until after exposure to acidic pH. A single neutralizing epitope (E1-c) includes E1 residue 132. Two dominant neutralizing domains have been identified on the Sindbis virus E2: E2-ab from E2-190 to 216 and E2-c from E2-62 to 159. E2-ab is likely to form a single loop and contain linear determinants while E2-c is strictly conformational involving several sites on the linear molecule. Both neutralizing and non-neutralizing E1 and E2 MAbs can protect and promote recovery from fatal encephalitis. E2 MAb can clear infectious virus from persistently infected cells by non-cytolytic process and acts synergistically with interferon.
Pure‐Tone Octave Masking in Listeners with Sensorineural Hearing Loss

Pure-tone octave masking was investigated in 14 listeners with sensorineural hearing loss to examine the hypothesis that the sensorineural ear introduces abnormal harmonic distortion. Thresholds fo...
Oxidative Addition of the C−S Bond of Thiophene to the (C5Me5)Rh(PMe3) Fragment: A Theoretical Study Revisited

Density functional theory (DFT) calculations on the C−S bond activation reaction of thiophene with the [(C5Me5)Rh(PMe3)] fragment have been reinvestigated, giving two new isomeric C−S bond activati...
Seed storage protein composition of non-nodulating soybean (Glycine max (L.) Merr.) and its influence on protein quality

A 53 kDa protein, which accumulates at low levels in non-nodulating Clark soybeans, was purified by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Polyclonal antibodies were raised against the gel-purified protein. N-terminal sequence analysis identified the 53 kDa protein as the beta-subunit of beta-conglycinin. Results from Western blot analysis, using antibodies raised against the purified beta-subunit of beta-conglycinin, revealed that accumulation of this protein was enhanced in non-nodulating soybeans when the plants were supplemented with nitrogen. Results from Northern blot analysis indicate that non-nodulating soybeans in general had lower levels of mRNA for the major soybean seed proteins. A one-time application of nitrogen to non-nodulating soybeans enhanced the accumulation of the 1.6 kb beta-conglycinin beta-subunit mRNA. The mRNA levels of the 2.1 kb beta-conglycinin alpha'-subunit and the 2.2 kb G4 glycinin in the non-nodulating soybeans were several-fold lower than in nodulating soybeans. Nitrogen application had no effect on the abundance of these RNA transcripts. The amount of RNA encoding an 8.5 kDa sulfur-rich protein was two-fold higher in non-nodulating soybeans when compared with nodulated soybeans. Nitrogen application reduced the abundance of this transcript to levels comparable with those of nodulated soybeans. Despite lower levels of the beta-subunit of beta-conglycinin, the methionine content of the total seed protein fraction was lower than that of nodulated soybeans. In contrast, non-nodulating soybeans contained more cysteine than nodulating soybeans.
Examination of the Equivalence of Self-Report Survey-Based Paper-and-Pencil and Internet Data Collection Methods.

Self-report survey-based data collection is increasingly carried out using the Internet, as opposed to the traditional paper-and-pencil method. However, previous research on the equivalence of these methods has yielded inconsistent findings. This may be due to methodological and statistical issues present in much of the literature, such as nonequivalent samples in different conditions due to recruitment, participant self-selection to conditions, and data collection procedures, as well as incomplete or inappropriate statistical procedures for examining equivalence. We conducted 2 studies examining the equivalence of paper-and-pencil and Internet data collection that accounted for these issues. In both studies, we used measures of personality, social desirability, and computer self-efficacy, and, in Study 2, we used personal growth initiative to assess quantitative equivalence (i.e., mean equivalence), qualitative equivalence (i.e., internal consistency and intercorrelations), and auxiliary equivalence (i.e., response rates, missing data, completion time, and comfort completing questionnaires using paper-and-pencil and the Internet). Study 1 investigated the effects of completing surveys via paper-and-pencil or the Internet in both traditional (i.e., lab) and natural (i.e., take-home) settings. Results indicated equivalence across conditions, except for auxiliary equivalence aspects of missing data and completion time. Study 2 examined mailed paper-and-pencil and Internet surveys without contact between experimenter and participants. Results indicated equivalence between conditions, except for auxiliary equivalence aspects of response rate for providing an address and completion time. Overall, the findings show that paper-and-pencil and Internet data collection methods are generally equivalent, particularly for quantitative and qualitative equivalence, with nonequivalence only for some aspects of auxiliary equivalence.
Diffraction contrast of fold domain boundaries in polyethylene single crystals

The dark-field diffraction contrast images of several types of fold domain boundaries in polyethylene single crystals have been characterized. Macrosector, microsector, {110} and {310} twin boundary contrast are shown to be due to the image shift which occurs when two diffracted beams contribute to the dark-field image.
Cerebral Averaged Potentials Preceding Oral Movement

The “readiness potential” is an event-related potential that shows increasing negativity at vertex and motor strip scalp recording sites prior to voluntary, unilateral limb movements. Though speech...
Surface analysis of unsized and sized carbon fibers

Abstract Atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and contact angle analyses were performed on unsized and sized carbon fibers to better understand the mechanism of adhesion in carbon fiber/polymer matrix composites. AFM images and surface roughness analyses showed that the sizing changes the surface topography on a microscopic scale. The total surface energy decreased from 70 mJ/m2 for unsized fiber to 54 mJ/m2 for Ultem® sized and to 36 mJ/m2 for PTPO sized fibers. The percentage of functional groups on the sized fibers decreased slightly compared to the unsized fibers. The surface functional groups and surface energies of fibers are critical properties in predicting fiber/matrix adhesion. Angle dependent XPS, voltage contrast XPS, and perimeter measurements revealed that the thickness of the poly(thioarylene phosphine oxide) (PTPO) sizing on the carbon fiber surface was greater than for the poly(etherimide) (Ultem®) sizing.
Liver transplantation in the first three months of life.

BACKGROUND Pediatric liver transplant recipients have traditionally been grouped according to age. Age-based classification schemes are useful in identifying clinical problems in selected age groups and also for developing solutions to these problems. Although infants in the first 3 months of life have not traditionally been considered a distinct age group, several features of these infants may distinguish them from other pediatric liver transplant recipients. METHODS The experience with liver transplantation in infants during the first 3 months of life in three large pediatric liver transplant programs (University of Chicago, Stanford University, and UCLA) was analyzed in order to characterize this group. RESULTS A total of 23 liver transplants were performed at these three centers in children younger than 3 months of age. This group of patients comprised approximately 37% of the U.S. experience between 1988 and 1994 according to United Network for Organ Sharing statistics. Age distribution at the time of transplantation included the following: <1 month, 28%; 1-2 months, 35%; and 2-3 months, 36%. Median age at the time of transplantation was 37 days (range, 7-90 days), and mean age was 57+/-30 days. Mean weight at the time of transplantation was 3.8+/-1.0 kg. Etiology of liver disease included idiopathic hepatitis, 52%; iron storage disease, 17%; and other causes, 31%. Types of liver allografts used included cadaveric, 85% (reduced size, 60%, and full-size, 25%); living donor, 15%; ABO-identical, 65%; and ABO-compatible, 35%. Actuarial patient and graft survival rates were 60% and 60% at 1 year and 60% and 42% at 2 years, respectively. Median follow-up was 1.5 years. Rejection occurred in 42% of patients, with a median time to first rejection of 13 days. Of these patients, 28% required steroids only and 14% required OKT3. Three patients (14%) were retransplanted at a median time to retransplantation of 1.6 years. Vascular thrombosis occurred in three patients (14%). CONCLUSIONS Liver transplantation performed in infants younger than 3 months of age (1) provides acceptable short- and long-term patient and graft survival, (2) is associated with significant rates of rejection, and (3) is not associated with excessive rates of vascular thrombosis. The etiology of end-stage liver disease occurring in the first 3 months of life is distinct from that in other pediatric liver transplant recipient age groups. These infants should be referred promptly for liver transplantation as reasonable survival can be expected.
Three-Dimensional Modeling of Rate-Dependent Deformation in Shape Memory Alloys at High Temperatures

Active structures composed of Shape Memory Alloys (SMAs) and High Temperature SMAs (HTSMAs) continue to be developed for applications that benefit from solid-state actuation. The need to account for the response of these materials under non-conventional loading paths that include elevated temperature conditions has become important. Conventional SMAs are exposed to such temperatures during processing, including final shape-setting. HTSMAs, by virtue of their title, are exposed to such high temperatures during transformation. This work addresses new developments in the constitutive modeling and numerical analysis pertaining to irrecoverable inelasticity in SMAs at high temperatures, where this behavior becomes rate-dependent. The description of such behavior requires the development of a theoretical framework able to capture the coupling between the rate-independent transformation and the rate-dependent creep. The proposed phase transformation-viscoplastic model is based on continuum thermodynamics; here the elastic relations, the inelastic evolution equations, and the transformation criteria are summarized. The evolution equation for the viscoplastic strain is non-homogeneous in time, and thus rate-dependency results. The viscoplastic parameters are generally assumed to exhibit a strong dependence on temperature. The rate-independent and rate-dependent constitutive equations that comprise the full 3-D model are numerically integrated using a scheme that accounts for both transformation and viscoplastic deformation in a coupled manner. The implementation allows for 3-D analysis of SMA bodies using an FEA framework that includes Abaqus and an associated user material subroutine. Example analyses are discussed, including shape-setting in a conventional SMA and experimentally validated structural analysis of an HTSMA specimen.© 2009 ASME
Uptake and distribution of C12 alkylbenzene in bluegill (Lepomis macrochirus)

The Bioconcentration Factor (BCF) for [14C)] Alkylbenzene in Bluegill Sunfish (Lepomis machrochirus, Rafinesque] was determined to be 35. The value is significantly smaller than the predicted BCF of 6300; the discrepancy is ascribed to metabolism. Alkylbenzene has similar patterns of tissue distribution and depuration rates when compared to its sulfonated counterpart, linear alkylbenzene sulfonate, which has been shown to be readily metabolized.
Genetic manipulation of cardiac Na+/Ca2+ exchange expression

Abstract The Na + /Ca 2+ exchanger (NCX) is the primary Ca 2+ extrusion mechanism in cardiomyocytes. To further investigate the role of NCX in excitation–contraction coupling and Ca 2+ homeostasis, we created murine models with altered expression levels of NCX. Homozygous overexpression of NCX resulted in mild cardiac hypertrophy. Decline of the Ca 2+ transient and relaxation of contraction were increased and the reverse mode of NCX was augmented. Overexpression also led to a higher susceptibility to ischemia–reperfusion injury and to a greater ability of NCX to trigger Ca 2+ -induced Ca 2+ release. Furthermore, an increase in peak L-type Ca 2+ current was observed suggesting a direct influence of NCX on L-type Ca 2+ current. Whereas global knockout of NCX led to prenatal death, a recently generated cardiac-specific NCX knockout mouse was viable with surprisingly normal contractile properties. Expression levels of other Ca 2+ -handling proteins were not altered. Ca 2+ influx in these animals is limited by a decrease of peak L-type Ca 2+ current. An alternative Ca 2+ efflux mechanism, presumably the plasma membrane Ca 2+ -ATPase, is sufficient to maintain Ca 2+ -homeostasis in the NCX knockout mice.
Experimental characterization of emittance growth induced by the nonuniform transverse laser distribution in a photoinjector

The emittance of a high-brightness electron beam from a photoinjector is affected by the transverse and longitudinal distributions of the laser beam illuminating the cathode. A nonuniform laser beam generates a nonuniform electron-beam distribution that experiences emittance growth on a time scale of the plasma period. Experiments were performed at the Brookhaven Accelerator Test Facility to investigate the emittance growth due to transversely nonuniform laser beams. Laser masks were fabricated to generate various laser distributions. Significant emittance growth was observed as the laser distribution deviated strongly from a uniform distribution. For cylindrically symmetric, nonuniform distributions, experimental results agree with PARMELA simulations. The emittance dependence on the bunch charge is linear as a function of the bunch charge for both uniform and nonuniform beams. For a uniform beam, the emittance measurements agree well with the predictions from PARMELA simulations, but the analytical approach overestimates the results. For nonuniform beams, analytical estimates are about 70% of the measurements. For noncylindrically symmetric, nonuniform beams, we observed that the emittance is linearly proportional to the rms laser nonuniformity and the best emittance for a perfectly uniform beam is extrapolated to be $1.07\ifmmode\pm\else\textpm\fi{}0.13\text{ }\mathrm{mm}\text{ }\mathrm{mrad}$ at 0.5 nC.
THE EFFECT OF INDUCED SECRETORY ACTIVITY ON THE CHOLESTEROL CONTENT OF THE IMMATURE RAT OVARY1

Although the metabolic degradation of steroid hormones has been extensively studied, the anabolic origin of these substances in the animal body has not received much attention. An important clue was furnished by Bloch (1945) who demonstrated that isotopically labelled cholesterol, fed to a pregnant woman, is in part converted to pregnandiol. The logical assumption is that such a conversion is by way of progesterone which, in the case of a woman in the late stages of pregnancy, may be assumed to have occurred in the placental tissues. Another indication that cholesterol may be utilized for the synthesis of steroid hormones is afforded by a number of studies (Sayers, Sayers, Fry, White and Long, 1944; Sayers, Sayers, Liang and Long, 1946; Long, 1947; Levin, 1945) in which it was shown that stimulation of the adrenal cortex, at least in the initial stages, is accompanied by loss of stored cholesterol from this gland.
A high melting structure in DNA distinguishes phases of the cell cycle.

Abstract Differential scanning microcalorimetry of the nuclei of dividing CHO cells revealed DNA structures that showed structural transitions at 60, 76, 88, and 105 °C (transitions I to IV, respectively). In cultures synchronized by isoleucine deprivation the enthalpies of transitions I and II were rather constant throughout the cell cycle. While the sum of the enthalpies of III and IV was nearly constant, the ratio of IV to III varied substantially from one phase of the cycle to another. A high IV:III ratio of 6 characterized G 1 while S phase gave a IV:III ratio of about 2. Cells containing metaphase chromosomes also showed a IV:III ratio near 2. The IV:III ratio for CHO cells showed a progressive decrease as the cells were maintained in isoleucine-free medium from 0 to 6 days.
Defect structures induced by high-energy displacement cascades in γ uranium

Abstract Displacement cascade simulations were conducted for the γ uranium system based on molecular dynamics. A recently developed modified embedded atom method (MEAM) potential was employed to replicate the atomic interactions while an embedded atom method (EAM) potential was adopted to help characterize the defect structures induced by the displacement cascades. The atomic displacement process was studied by providing primary knock-on atoms (PKAs) with kinetic energies from 1 keV to 50 keV. The influence of the PKA incident direction was examined. The defect structures were analyzed after the systems were fully relaxed. The states of the self-interstitial atoms (SIAs) were categorized into various types of dumbbells, the crowdion, and the octahedral interstitial. The voids were determined to have a polyhedral shape with {1 1 0} facets. The size distribution of the voids was also obtained. The results of this study not only expand the knowledge of the microstructural evolution in irradiated γ uranium, but also provide valuable references for the radiation-induced defects in uranium alloy fuels.
Synthesis through meta-ethnography: paradoxes, enhancements, and possibilities

Despite theoretical differences and methodological questions, the conversation about synthesizing qualitative research raises interest. Meta-ethnography, as initially described by Noblit and Hare (...
Efficient Computer Network Anomaly Detection by Changepoint Detection Methods

We consider the problem of efficient on-line anomaly detection in computer network traffic. The problem is approached statistically, as that of sequential (quickest) changepoint detection. A multi-cyclic setting of quickest change detection is a natural fit for this problem. We propose a novel score-based multi-cyclic detection algorithm. The algorithm is based on the so-called Shiryaev-Roberts procedure. This procedure is as easy to employ in practice and as computationally inexpensive as the popular Cumulative Sum chart and the Exponentially Weighted Moving Average scheme. The likelihood ratio based Shiryaev-Roberts procedure has appealing optimality properties, particularly it is exactly optimal in a multi-cyclic setting geared to detect a change occurring at a far time horizon. It is therefore expected that an intrusion detection algorithm based on the Shiryaev-Roberts procedure will perform better than other detection schemes. This is confirmed experimentally for real traces. We also discuss the possibility of complementing our anomaly detection algorithm with a spectral-signature intrusion detection system with false alarm filtering and true attack confirmation capability, so as to obtain a synergistic system.
The Geography of US Union Elections 3: The Context and Structure of Union Electoral Performance (the International Brotherhood of Electrical Workers Union and the United Auto Workers Union, 1970–82)

This paper is an extension of previous research on the geography of union elections. A model of union organization is proposed, relevant to the institutional and political structure of US labor legislation. Implications are drawn for unions' organizing strategies, and their likely electoral performance at the local level. It is argued that the structural imperatives faced by unions are inherently incomplete; local discretion is built-in to the structure of labor relations. Alternative empirical forms of the proposed model are considered and the advantages of a probit methodology discussed. Empirical analysis is based upon representation elections involving the International Brotherhood of Electrical Workers union and the United Auto Workers union over the period 1970–82. To illustrate the implications of the derived empirical results, a series of scenarios are discussed involving both unions and their possible options for organizing at the local level.
Leisure-Time Screen-Based Sedentary Behavior and Leukocyte Telomere Length: Implications for a New Leisure-Time Screen-Based Sedentary Behavior Mechanism

The field of sedentary behavior epidemiology is emerging. Short leukocyte telomere length (LTL) is a hallmark characteristic of aging, but LTL is also associated with morbidity and mortality independent of age. To my knowledge, only one study has examined the association between sedentary behavior and LTL. The purpose of this study was to examine the association between screen-based sedentary behavior and LTL. Data from the 1999-2002 National Health and Nutrition Examination Survey were used (N=6405; age, 20-84 years). Leisure-time screen-based sedentary behavior (television, video games, computer use) was assessed via questionnaire, and LTL was extracted from DNA in whole blood with the LTL assay performed using quantitative polymerase chain reaction. After adjustments (including age and physical activity), for every 1-hour increase in leisure-time screen-based sedentary behavior, participants had a 7% increased odds (odds ratio, 1.07; 95% CI, 1.00-1.13; P=.04) of having LTL in the lowest tertile (vs highest); leisure-time screen-based sedentary behavior was not associated with values in the middle (vs highest) tertile (odds ratio, 1.01; 95% CI, 0.95-1.07; P=.62). The results of this study revealed that greater leisure-time screen-based sedentary behavior is associated with shorter LTL.
Object-oriented programming and design patterns

When teaching object-oriented concepts, design patterns are usually left until the end or left out entirely. In this paper, design patterns are related to the rules of object-oriented design, strongly suggesting that these two concepts should be taught together as beneficial for the understanding of both.
Early results of posterior leaflet folding plasty for mitral valve reconstruction.

Abstract Background . Standard reconstruction for posterior mitral leaflet (PML) disease is quadrangular resection and annular plication; when the PML is excessively high, a sliding plasty is used. We have developed an alternative technique, a posterior leaflet folding plasty . It is performed by folding down the cut vertical edges of the PML. The central height of the PML is reduced, leaflet coaptation is moved posteriorly, and annular plication is unnecessary. Methods . From March 1995 to August 1996, 26 (17.9%) of 145 patients undergoing mitral reconstruction had a posterior leaflet folding plasty. Concomitant procedures included anterior leaflet resection or resuspension and myotomy and myectomy. In 3 patients, the PML resection extended to a commissure. Results . There was one death and no reoperations. The mean New York Heart Association class was improved from 2.4 preoperatively to 1.4. There was no major postoperative mitral insufficiency in the 26 patients. Systolic anterior motion was transiently seen in 1 patient in whom left ventricular outflow tract obstruction was present preoperatively. Conclusions . The data demonstrate the safety and short-term efficacy of posterior leaflet folding plasty. This technique may help avoid systolic anterior motion after reconstruction of the PML.
Uncertainty analysis of a commercial microwave noise temperature measurement system using Monte Carlo simulations

A Monte Carlo simulation, a non-linear fitting routine, and an uncertainty extraction routine are used to analyze the uncertainty of a commercial microwave noise temperature measurement system. Measured data for an S/C band synthetic FET-based cold load, two microwave solid-state noise diode hot loads, and an ambient load is obtained, and the measurement system uncertainties are subsequently assessed using different DUTs. An estimation of the measurement system uncertainties is determined for a range of DUT temperatures, and the results are consistent with the noise temperature uncertainties calculated from the measured data at the same frequency. Copyright © 2010 John Wiley & Sons, Ltd.
Achieving Cultural Competency: Assessment of US-Based Counselor Educators Instructing Internationally

This article presents the outcomes of a qualitative investigation addressing the global exchange of counselor education. Findings delineate key traits and behaviors applied by counselor educators and counseling psychologists in cross-cultural exchanges. Personal traits noted by educators as essential for international exchanges included flexibility, respect, openness to learning, and passion for the experiences provided by international travel. Factors that increased cultural competency were cited as communication skills, increased comprehension of the context, and understanding of the counseling profession within the culture.
Atmospheric Ozone and the History of Life.

Abstract Biological evolution, in its early stages, may have been constrained by the solar ultraviolet radiation that would have penetrated to the ground if the atmosphere at this time contained little or no oxygen and therefore little or no ozone. In order to provide a more quantitative basis for the examination of this possibility we have used a simple photochemical model to evaluate ozone densities in atmospheres resembling the present atmosphere in most respects, but containing less oxygen. As the amount of oxygen in the atmosphere is reduced, we find that the ozone column density initially increases. Only when the amount of oxygen in the atmosphere falls below 10−1 of its present level does the ozone column density begin to decrease. Our results suggest that very little atmospheric oxygen (possibly 10−3 of the present amount) is required to produce a biologically effective ozone screen.
AP1000 Verification of Water Sources for Long-Term Recirculation Cooling Following a LOCA

The AP1000 Nuclear Power Plant uses natural recirculation of coolant to cool the core following a postulated Loss Of Coolant Accident (LOCA). Recirculation screens are provided in strategic areas of the plant to remove debris that might migrate with the water in containment and adversely affect core cooling. An evaluation of the potential for debris to plug the AP1000 recirculation screens was performed consistent with the guidance identified in Regulatory Guide 1.82 Revision 3, the Pressurized Water Reactor (PWR) Industry Guidance of NEI 04-07, and the Nuclear Regulatory Commission’s Safety Evaluation on NEI 04-07. The evaluation considered various contributors to screen plugging including debris that could be produced by a LOCA, resident containment debris and post-accident chemical products that might be generated in the coolant pool that forms on the containment floor post-accident. The evaluation accounted for the AP1000 containment design, equipment locations, recirculation screen redesign and containment cleanliness program. A unique aspect of this evaluation is the use of available industry data and its application to the AP1000 design to support the evaluation. Specifically, available industry data from existing plant walkdowns was used to both characterize the fibrous and particulate debris that could comprise resident debris in containment prior to the LOCA, and estimate the amount of that debris. The evaluation also combined generic PWR Industry containment sump chemical effects information with AP1000 specific post-accident coolant chemistry and sump transient conditions to evaluate potential chemical effects. The collection of resident containment debris on the recirculation screens in the post-LOCA recirculation mode may result in a head loss across containment recirculation screens that could restrict the recirculation flow required to cool the core effectively. Using specific design features of the AP1000, the debris loading evaluated from latent containment debris and post-accident chemical effects and conservatively applying an available screen head loss correlation, the head loss across the AP1000 containment recirculation screens due to the collection of latent debris on the screen under natural circulation conditions was calculated. Calculations were also made for pressure drop across the AP1000 In-Containment Refueling Water Storage Tank (IRWST) screens resulting from latent containment debris accumulation on those screens under accident conditions. Finally, calculations were made for pressure drops at the AP1000 core resulting from debris accumulation on the bottom of the fuel. This paper will present the methods used to apply the available PWR Industry data to the AP1000 design, along with the results of the calculations performed which demonstrate the acceptability of the design of the AP1000 recirculation screens.© 2008 ASME
Simple versatile method for fabricating guided-wave gratings.

A simplifed method which requires only a single mirror for making guided-wave gratings (periodic, chirped, and curved) is described, and the properties of gratings fabricated by this method are reported.
An approach to generate large and small leptonic mixing angles

We take up the point of view that Yukawa couplings can be either 0 or 1, and the mass patterns of fermions are generated purely from the structure of the Yukawa matrices. We utilize such neutrino as well as charged leptonic textures which lead to (maximal) mixing angles of π/4 in each sector for relevant transitions. The combined leptonic CKM mixing angles are π/4±π/4 which lead to very small sin 22Θ relevant to solar neutrino and LSND experiments. We propose that, on the other hand, the absence of the charged leptonic partner of the sterile neutrino maintains the angle π/4 from the neutrino sector for the transition νμ νs and hence the atmospheric neutrino anomaly is explained through maximal mixing.
Two benzene metabolites, catechol and hydroquinone, produce a synergistic induction of micronuclei and toxicity in cultured human lymphocytes

A mixture of two benzene metabolites, hydroquinone and catechol, produces a striking synergistic genotoxic response in cultured human lymphocytes. This was demonstrated using an anti-kinetochore antibody modification of the micronucleus assay. Treatment with hydroquinone alone or in combination with phenol produced a 3-fold increase in micronucleated cells over background. Treatment with catechol or phenol alone and in combination produced only minor increases in the number of micronucleated cells. In contrast, simultaneous treatment with equimolar (75 microM) concentrations of hydroquinone and catechol resulted in a greater than 16-fold induction of micronucleated cells. Given an additivity model, 20 additional micronucleated cells would be expected (after correcting for background frequencies), yet 140 were observed. Further analysis revealed that over 90% of the micronucleated cells stained positively for kinetochores, indicating a high probability that these micronuclei contain entire chromosomes. This synergistic response appears to occur only at equimolar levels of hydroquinone and catechol. These results suggest that these metabolites are acting together to disrupt the mitotic spindle and interfere with chromosome segregation. These data provide further support for the hypothesis that multiple metabolites acting in concert are involved in the benzene-induced genotoxicity and leukemia in humans.