cssi/SciSciGPT-SciSciNet huggingface dataset:
Dangling bonds and dislocations in semiconductors.

Dangling bonds and dislocations in semiconductors, noting existence of core charge dependent localized state in gap caused by local decrease in atom density
Assay of progesterone in oil injectables.

A method is presented for the quantitative determination of progesterone in oil solutions. The ketosteroid is isolated by partition chromatography using nitro-methane on purified siliceous earth as the immobile phase and n -heptane as the eluent. The assay is based on the ultraviolet absorbance in ethanol solution at the maximum near 241 m/i. The identity of the separated progesterone is confirmed by determining the infrared spectrum in carbon disulfide solution.
META-ANALYSIS AND ENDOCRINOLOGY

It is likely that more studies that use meta-analysis will be published in the endocrinologic literature. Major strengths of meta-analysis are the systematic ascertainment of research on a given topic and the explicit delineation of reasons for accepting or rejecting studies as a basis for drawing conclusions. The tendency of meta-analysis to focus on a single estimate of effect and to ignore heterogeneity are problems both with the conduct of meta-analysis and the way in which it is interpreted. Meta-analysis cannot overcome bias in the original studies. It is difficult to perform a good meta-analysis and easy to perform a bad one. The critical reader should not be overawed by the results of a meta-analysis. Reading a meta-analysis should not substitute for careful reading of the primary studies on which the meta-analysis is based. Meta-analysis should not be used to stifle the conduct of original research.
Effects of environment on morphology of rat cerebral cortex and hippocampus.

Cortical depth differences were found between male rats exposed to enriched or impoverished environmental conditions for successively shorter times, i.e., for 15 days (from 25 to 40 days of age), for seven days (25 to 32 days of age), and for four days (26 to 30 or 60 to 64 days of age). If the experiments began at weaning (at 25 days of age), the cortical depth changes were caused primarily by impoverishment. If the animals were young adults (60 days of age), upon entering their respective conditions, the cortical changes were induced by enrichment. No cortical depth differences were found between enriched and impoverished rats after one day of differential experience, from 60 to 61 days of age. In every age group and for every duration, except for the one day group, the dorsal-medial segment of the occipital cortex responded to the environmental conditions. No significant hippocampal depth differences were noted between enriched and impoverished animals.
Testing a palaeomagnetic study for the averaging of secular variation

Summary. It is shown that the interval estimate for K given by Cox (1969) is inappropriate as a test for determining whether secular variation has been averaged out in a particular study. The appropriate test is presented in two formulations, one for use with χ2 tables and the other for use with F tables. The well known secular variation models are investigated and it is shown that Model A due to Irving & Ward (1964) is, statistically, the most efficient predictor. Finally, for the 83 palaeomagnetic results selected by Brock (1971), it is shown that the most efficient predictor for the secular variation K is k′= 18.1 (1 + 3 sin2λ), where λ is the palaeolatitude, and the uncertainty in this predicted value is discussed.
Astrophysics: Supernova seen through γ-ray eyes.

Observations of γ-ray photons from a type Ia supernova indicate that stellar explosions of this kind get their energy from sudden thermonuclear fusion in the progenitor star. See Letter p.406 The 'standard candles' of cosmology, type Ia supernovae, are thought to derive from thermonuclear explosions of white dwarf stars, and to be accompanied by the release of large amounts of radioactive nickel-56, decaying into cobalt and iron. This paper reports the first ever detection of cobalt-56 γ-ray emission lines from a type Ia supernova, SN 2014J. The observed spectra are in broad agreement with the classic model of a white dwarf explosion massive enough to be unstable to gravitational collapse, but do not exclude more complicated merger scenarios.
Attachment Parenting: An Exploration of Demographics and Practices.

The goal of this study was to identify parenting behaviors practiced by a self‐selected group of North American parents who identify themselves as attachment parents. This type of parenting is based on behaviors that are focused on infant needs and demands perhaps more strongly than are traditional mainstream western parenting practices. However, little is known about the demographics of the parents or the actual parameters of their behaviors. In order to further investigate these behaviors, a self‐report questionnaire was developed for use in the study. This questionnaire was included, without return postage, in an international parenting magazine, Compleat Mother. A sample of 275 mothers returned the instrument. Respondents were predominantly married, college educated and White. The respondents reported that of their infants the majority were exclusively breastfed on the infant’s cue and for an extended period of time, coslept and were held or nursed during the transition to sleep. These practices are d...
Evolution of tagged particles in non-reversible particle systems

We derive an ODE for the macroscopic evolution of a tagged particle in models such as asymmetric simple exclusions and zero range processes. The right-hand side of the ODE is discontinuous and its solutions are understood in the Filippov sense. We establish the uniqueness of the ODE, and explore its relationship with the hydrodynamic equation of the particle density.
Role of Hydroxymethyl Sulfate Esters in Aromatic Hydrocarbon Carcinogenesis

Abstract The unified hypothesis, for the carcinogenic properties of aromatic hydrocarbons, predicts that hydroxylation of meso-methyl groups followed by the formation of electrophilic esters bearing a good leaving group, such as sulfate, phosphate, or acetate, play a role in the DNA damage, mutagenesis and carcinogenesis of alkyl-substituted hydrocarbons such as 7,12-dimethylbenz[a]anthracene, 3-methylcholanthrene, and 6-methylbenzo[a]pyrene, and even unsubstituted hydrocarbons such as benzo[a]pyrene. Activation of hydroxyalkyl metabolites to electrophilic mutagens has been shown to be catalyzed by 3′-phosphoadenosine-5′-phosphosulfate-dependent sulfotransferase activity. Recent studies demonstrate that a number of sulfate esters account for most, if not all, of the complete carcinogenic activity of their hydroxyalkyl precursors by repeated s.c. injection in female Sprague-Dawley rats. In addition to hydroxymethyl hydrocarbons, some aromatics with secondary benzylic hydroxyl groups are also metabolically ...
A 2-D liquid separations/mass mapping method for interlysate comparison of ovarian cancers.

A two-dimensional liquid phase separation of proteins from whole cell lysates coupled on-line to an electrospray-ionization time-of-flight (ESI-TOF) mass spectrometer (MS) is used to map the protein content of ovarian surface epithelial cells (OSE) and an ovarian carcinoma-derived cell line (ES2). The two dimensions involve the use of liquid isoelectric focusing as the first phase and nonporous silica reversed-phase HPLC as the second phase of separation. Accurate molecular weight (MW) values are then obtained upon the basis of ESI-TOFMS so that an image of isolectric point (pI) versus MW analogous to 2-D gel electrophoresis is produced. The accurate MW together with the pI fraction and corresponding hydrophobicity (%B) are used to tag each protein so that protein expression can be compared in interlysate studies. Each protein is also identified on the basis of matrix-assisted laser desorption−ionization (MALDI) TOFMS peptide mapping and intact MW so that a standard map is produced against which other cel...
Modified arc-length adaptive algorithms for degenerate reaction-diffusion equations

This paper is concerned with modified adaptive difference schemes for solving degenerate nonlinear reaction-diffusion equations with singular source terms. The adaptive mechanisms both in space and time are considered. Modified monitor functions based on arc-lengths of the rate function u"t are constructed. Further analyses are given on properties of the numerical schemes derived. We show that, under proper smoothness, consistency and step-size constraints, the numerical solution obtained preserves the monotonicity of the physical solution. Numerical experiments are given to demonstrate the monotonicity and convergence properties of the methods.
InGaAs(0.98 μm)/GaAs vertical cavity surface emitting laser grown by gas-source molecular beam epitaxy

Abstract We report the growth of InGaAs/GaAs vertical cavity surface emitting lasers (VCSELs) with an emission wavelength at 0.98 μm by gas-source molecular beam epitaxy (GSMBE). The surface emitting laser diodes are composed of a 15-pair p + GaAs/AlAs graded mirror with a 3-quantum well In 0.2 Ga 0.8 As active region and a 16.5-pair n + GaAs/AlAs grade mirror on an n + GaAs substrate. We use a simple interferometric technique for in-situ monitoring and feedback control of layer thickness to obtain a highly reproducible Bragg reflector. This technique uses an optical pyrometer to measure apparent temperature oscillations of the growing epi-layer surface. These measurements can be performed with continuous substrate rotation and without any growth interruption. The growing layer thickness can then be related to the apparent temperature oscillation spectrum. When the layer reaches the desired thickness, the growth of the subsequent layer is then initiated. By making layer thickness measurements and control in real-time throughout the entire growth cycle of the structure, the center of the mirror reflectivity and the Fabry-Perot resonance at the desired wavelength can be reproducibly obtained. The reproducibility of the center wavelength and FWHM of the reflectivity stop-band with a variation of ≤ 0.2% was achieved in the AlAs/GaAs mirror stacks grown using this technique. The VCSEL structures with a variation of the Fabry-Perot wavelength of ≤ 0.4% have been grown. Bottom-emitting laser diodes were fabricated and operated CW at room temperature. CW threshold currents of 3 and 6 mA are measured at room temperature for 10 and 25 μm diameter lasers, respectively. Output powers higher than 15 mW are obtained from these devices. These devices have an external quantum efficiency higher than 40%.
Stress-induced depression of motor activity correlates with regional changes in brain norepinephrine but not in dopamine

This experiment examined how inescapable tail shock alters the level of dopamine and norepinephrine within various brain regions of the rat and the relationship of these changes to the depression of motor activity produced by the shock. Following exposure to tail shock that is known to interfere with acquisition of active behavioral tasks, animals were briefly tested for spontaneous motor activity and then sacrificed for neurochemical measures. Norepinephrine and dopamine levels in the frontal cortex, brain stem, striatum, olfactory tubercle, hypothalamus, hippocampus, septum, and amygdala were measured by a sensitive radicenzymatic technique. Exposure to 45 min of tail shock did not alter motor activity significantly, but shock sessions of 60 and 75 min duration produced a marked decrease in motor activity. Levels of dopamine were found to be very little changed in all brain regions studied except for the hypothalamus, in which a substantial rise in dopamine level was observed. Norepinephrine levels, in contrast, fell in many brain regions in response to shock. The fall in norepinephrine levels observed in twi brain regions was significantly correlated with the decline in motor activity (brain stemr=+0.70, hypothalamusr=+0.60) These data suggest that deficits in active motor behavior produced by shock parameters similar to those used in this study may reflect concomitant disturbances of noradrenergic function in specific brain regions.
Coding of intention in the posterior parietal cortex

To look at or reach for what we see, spatial information from the visual system must be transformed into a motor plan. The posterior parietal cortex (PPC) is well placed to perform this function, because it lies between visual areas, which encode spatial information, and motor cortical areas. The PPC contains several subdivisions, which are generally conceived as high-order sensory areas. Neurons in area 7a and the lateral intraparietal area fire before and during visually guided saccades. Other neurons in areas 7a and 5 are active before and during visually guided arm movements. These areas are also active during memory tasks in which the animal remembers the location of a target for hundreds of milliseconds before making an eye or arm movement. Such activity could reflect either visual attention or the intention to make movements. This question is difficult to resolve, because even if the animal maintains fixation while directing attention to a peripheral location, the observed neuronal activity could reflect movements that are planned but not executed. To address this, we recorded from the PPC while monkeys planned either reaches or saccades to a single remembered location. We now report that, for most neurons, activity before the movement depended on the type of movement being planned. We conclude that PPC contains signals related to what the animal intends to do.
The coming of age of our understanding of the enterohepatic circulation of bile salts

Recent advances in molecular biology have greatly accelerated knowledge relating to the significance of the enterohepatic circulation of bile salts. This review highlights the role that both oxysterols and bile salts play as ligands which, when bound to nuclear hormone receptors, activate transcription factors that set into play feed-forward catabolism of cholesterol to bile salts and feedback control of bile acid synthesis. The nuclear hormone receptors, liver X receptor (LXR) and farnesoid X receptor (FXR) both combined as heterodimers with retinoid X receptor and with oxysterols and bile salts, respectively as their ligands, initiate powerful genetic controls over cholesterol and bile acid homeostatic mechanisms. LXR/RXR signals molecular control of feed-forward catabolism of cholesterol to bile acids while FXR/RXR initiates feedback control of bile acid synthesis. An additional nuclear hormone receptor, small heterodimer partner (SHP), is required to inhibit the competence factor, liver receptor homolog-1 to achieve repression of bile acid synthesis in the liver and in so doing SHP autoregulates its own function. Additionally, while bile acid synthesis is repressed, pool size is preserved by the action of FXR/RXR at both hepatic and intestinal levels, which genetically signals enhanced hepatocyte bile salt transport by the bile salt export pump (BSEP) and the ileal bile acid binding protein (IBABP) for ileal reabsorption. During activation of cholesterol catabolism, LXR/RXR enhances reverse cholesterol transport by increasing cholesterol efflux via the ABC-1 transporter from extrahepatic cells. This cholesterol is then taken up by high-density lipoprotein (HDL) and transported back to the liver for further cholesterol catabolism and elimination in bile. The genetic coordination of nuclear hormone receptor function within the territory of the enterohepatic of bile salts allows for normal cholesterol and bile acid homeostasis thereby preventing atherosclerosis.
Victim-offender race and support for capital punishment: A factorial design approach

Existing research suggests that juries are more likely to condemn murderers to death when offenders are black victims are white. It remains to be seen, however, whether these decisions reflect broader racial prejudices in society that are imported into the jury room. If they do, then insuring equity in capital sentencing may be beyond reach. Accordingly, this study uses factorial design methodology to examine whether members of the general public are more supportive of capital punishment when asked to rate a vignette describing a murder involving a white victim and black offender as opposed to other victim-offender racial combinations. Our analyses suggest that the race of the offender, but not the victim, has a significant influence on support for capital punishment. Thus, procedural safeguards alone may be unable to eliminate racial bias in capital sentencing.
THE PERINATAL COURSE OF METHADONE MAINTAINED AND NONMETHADONE MAINTAINED POLYDRUG ABUSERS

Methadone maintenance is important for the management of pregnant, opiate dependent women usually at risk obstetrically. Controlled daily doses of methadone may decrease perinatal complications related to the use of street drugs. This study was a retrospective comparison of the perinatal courses of 46 methadone maintained (group 1) and 46 non-methadone maintained (group 2) drug dependent women who were matched for age and race. The mean age was 26 years and the sample was 78% black, 20% caucasian, and 2% Hispanic. Urine toxicologies confirmed reduced use of illicit drugs such as heroin, and the use of licit drugs such as diazepam and amphetamines by all women. Obstetrical histories, complications and delivery methods are compared as were gestational ages, birth weights, Apgar scores and neonatal complications. Analysis revealed that group 1 women attended prenatal clinic twice as often as did group 2 women (X visits=7.6 vs. 3.4, t=5.47, p <.001). They also reported significantly fewer spontaneous abortions (t= 2.03, p < .05) prior to the most recent pregnancy. Although 1 minute Apgar scores did not differ, 5 minute scores were significantly lower in offspring of methadone maintained women (X=8.4 vs. 8.9, t=1.99, p <.05). No other significant differences were noted. These data suggest that in a setting of comprehensive care and methadone maintenance, opiate addicted, polydrug abusing women have an impetus toward obtaining prenatal care and can experience no more perinatal difficulties than similarly supervised nonopiate polydrug abusers.
Touching Mars: 1998 status of the Mars Robotic Exploration Program

Abstract The Mars Robotic Exploration Program is sending missions every 26 months to orbit and land on Mars and, in 2005, to return a sample to Earth. The highly successful Mars Pathfinder and Mars Global Surveyor missions were launched in 1996. Mars Surveyor 98 will launch in December 1998 and January 1999, to be followed by an orbiter, lander and rover in 2001 and again in 2003. A sample return mission is planned for a 2005 launch. The primary goal of the program after 2001 is the search for evidence of past or present life; and the strategy of orbiters, sample collecting rovers, and sample returns is designed to enrich the chances that such evidence will be discovered. The program is also pioneering “faster, better, cheaper” project management and implementation techniques for NASA. Frequently updated results of the program are available at http://mars.jpl.nasa.gov.
Ion Source Development for the los Alamos Heavy Ion Fusion Injector

A multi-beam injector is being designed and built at Los Alamos for the U.S. Heavy Ion Fusion Program [1]. As part of this program, development of an aluminum-spark, pulsed plasma source is being carried out. Faraday cup diagnostics are used to study current emission and to map the current profile. An aluminum oxide scintillator with photographic film is used in conjunction with a pepper-pot to obtain time integrated emittance values.
Electrically conductive pseudo IPNs of linear poly(carbonate-urethane) and crosslinked polychloroprene

A number of pseudo IPNs of poly(carbonate-urethane) (PCU) and crosslinked polychloroprene (CR) have been synthesized and characterized. The single phase morphology of these novel pseudo IPNs has been confirmed by DSC measurements and electron microscopy. The room temperature electrical conductives of homopolymers and pseudo IPNs have been investigated for both undoped and iodine-doped samples. © 1994 John Wiley & Sons, Inc.
Abstract ED01-03: Metabolomics of disease progression

While the total potential of a biological systems response is defined by their genes, and the organism9s desired response (to its current status) may be embodied in their transcripts, the metabolome embodies what an organism is actually of doing at a biochemical level. For this reason the metabolomic data may be quite diagnostic of a given disease state, that may or may not be dictated by either the genetic or transcriptomic levels. In this presentation we will discuss an application of metabolomics to define a series of biomarkers. The subsequent explorations of the details of this biomarker have revealed mechanisms that are likely to be significant to the progression of cancer. Citation Information: Cancer Prev Res 2010;3(12 Suppl):ED01-03.
Is there a general paradigm of cyclic AMP action in eukaryotes

The cyclic AMP control system in eukaryotes has been highly conserved evolutionarily in four of its central properties. Such conservation suggests conservation of the regulatory function of cyclic AMP. Conservation is seen in the properties of adenylate cyclase, cyclic AMP-dependent protein kinase and, among diverse lower eukaryotes, the control of endogenous cyclic AMP levels. A conserved regulatory response to cyclic AMP is the stimulation of glycolysis and inhibition of gluconeogenesis. The control of glycolysis and gluconeogenesis is proposed to be evidence of general pattern of cyclic AMP action in many lower and higher eukaryotic cells.
Effects of hypoxia, hyperoxia, and hypercapnia on baseline and stimulus-evoked BOLD, CBF, and CMRO2 in spontaneously breathing animals

Functional magnetic resonance imaging (fMRI) was used to investigate the effects of inspired hypoxic, hyperoxic, and hypercapnic gases on baseline and stimulus-evoked changes in blood oxygenation level-dependent (BOLD) signals, cerebral blood flow (CBF), and the cerebral metabolic rate of oxygen (CMRO2) in spontaneously breathing rats under isoflurane anesthesia. Each animal was subjected to a baseline period of six inspired gas conditions (9% O2, 12% O2, 21% O2, 100% O2, 5% CO2, and 10% CO2) followed by a superimposed period of forepaw stimulation. Significant stimulus-evoked fMRI responses were found in the primary somatosensory cortices. Relative fMRI responses to forepaw stimulation varied across gas conditions and were dependent on baseline physiology, whereas absolute fMRI responses were similar across moderate gas conditions (12% O2, 21% O2 100% O2, and 5% CO2) and were relatively independent of baseline physiology. Consistent with data obtained using well-established techniques, baseline and stimulus-evoked CMRO2 were invariant across moderate physiological perturbations thereby supporting a CMRO2-fMRI technique for non-invasive CMRO2 measurement. However, under 9% O2 and 10% CO2, stimulus-evoked CBF and BOLD were substantially reduced and the CMRO2 formalism appeared invalid, likely due to attenuated neurovascular coupling and/or a failure of the model under extreme physiological perturbations. These findings demonstrate that absolute fMRI measurements help distinguish neural from non-neural contributions to the fMRI signals and may lend a more accurate measure of brain activity during states of altered basal physiology. Moreover, since numerous pharmacologic agents, pathophysiological states, and psychiatric conditions alter baseline physiology independent of neural activity, these results have implications for neuroimaging studies using relative fMRI changes to map brain activity.
Thermodynamic properties of the liquid Sn−Ge and Sn−Au systems by mass spectrometry

The activities and partial molar heats of mixing have been determined for the liquid Sn−Ge system at 1773 K and the liquid Sn−Au system at 1873 K. The experimental technique consisted of analyzing Knudsen cell effusates with a TOF mass spectrometer. The ion current ratios for the monomeric vapor species were measured as a function of temperature and composition and the thermodynamic properties calculated using a modified form of the Gibbs-Duhem equations.
Photophysical and Energy-Transfer Properties of (Salen)zinc Complexes and Supramolecular Assemblies

Keywords: Host-guest systems / Fluorescence / Supramolecular chemistry / Salen ligands The absorption, emission, and energy-transfer properties of monomeric and supramolecular (salen)Zn complexes (square and rectangular assemblies) are reported. The monomeric complexes fluoresce in solution, displaying photophysical behavior similar to typical (porphyrin)zinc complexes. Rhenium coordination chemistry is used to assemble molecular rectangles and squares that largely retain the photophysical properties of the parent compounds. Host-guest assemblies
Apoptotic Activities of Wild-Type and Alzheimer's Disease-Related Mutant Presenilins in Drosophila melanogaster

Mutant human presenilins cause early-onset familial Alzheimer's disease and render cells susceptible to apoptosis in cultured cell models. We show that loss of presenilin function in Drosophila melanogaster increases levels of apoptosis in developing tissues. Moreover, overexpression of presenilin causes apoptotic and neurogenic phenotypes resembling those of Presenilin loss-of-function mutants, suggesting that presenilin exerts a dominant negative effect when expressed at high levels. In Drosophila S2 cells, Psn overexpression leads to reduced Notch receptor synthesis affecting levels of the intact approximately 300-kD precursor and its approximately 120-kD processed COOH-terminal derivatives. Presenilin-induced apoptosis is cell autonomous and can be blocked by constitutive Notch activation, suggesting that the increased cell death is due to a developmental mechanism that eliminates improperly specified cell types. We describe a genetic model in which the apoptotic activities of wild-type and mutant presenilins can be assessed, and we find that Alzheimer's disease-linked mutant presenilins are less effective at inducing apoptosis than wild-type presenilin.
Effect of chromium on low-temperature deformation of high-purity iron

A series of very low interstitial Fe-Cr alloys containing 0, 1, 3, 5, and 10 wt% Cr were prepared by vacuum melting and fabricated under argon to 1.83 mm diam wires exposed in an alumina system to wet hydrogen for 200 h at 1423 K followed by 1000 h in ZrH2-purified hydrogen at 1573 K. The wires were then transverse-rolled into thin sheet and cut into tensile specimens subjected to electropolishing and strained to fracture in a series of cryogenic baths ranging from 4.2 K to room temperature. It is shown that small Cr additions lower the twinning stress so that yielding occurs by twinning rather than by slip. Cr in amounts up to 10 wt% has little effect on the yield strength of high-purity Fe between 147 and 300 K, and ductility is not greatly affected at any test temperature. Higher solute contents provide appreciable strengthening only at temperatures of 112 K and below.
Inhibition of Prolyl Endopeptidase by Synthetic β-Casein Peptides and Their Derivatives with a C-Terminal Prolinol or Prolinal

(1992). Inhibition of Prolyl Endopeptidase by Synthetic β-Casein Peptides and Their Derivatives with a C-Terminal Prolinol or Prolinal. Bioscience, Biotechnology, and Biochemistry: Vol. 56, No. 6, pp. 976-977.
Honk if you like minorities: Vuvuzela attitudes predict outgroup liking

The 2010 FIFA World Cup in South Africa generated extensive controversy over spectators’ use of the African vuvuzela trumpet. We asked 123 White American participants about their opinions of vuvuzelas as well as their attitudes towards a variety of racial/ethnic minority groups including immigrants, African Americans, and Latinos. We found that the less participants liked vuvuzelas, the less positively they also tended to feel toward minority groups. Furthermore, respondents who liked vuvuzelas the least were also less generally open to change. These findings suggest that the vuvuzela controversy was about more than just a plastic trumpet – it was also an episode of differential ingroup/outgroup perceptions and a lack of openness to new things.
Homoclinic tangle of the ideal separatrix in the DIII-D tokamak from (30, 10) + (40, 10) perturbation

Trajectories of magnetic field lines are a 1½ degree of freedom Hamiltonian system. The perturbed separatrix in a divertor tokamak is radically different from the unperturbed one. This is because magnetic asymmetries cause the separatrix to form extremely complicated structures called homoclinic tangles. The shape of flux surfaces in the edge region of divertor tokamaks such as the DIII (J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)) is fundamentally different from near-circular. Recently, a new method is developed to calculate the homoclinic tangle and lobes of the separatrix of divertor tokamaks in physical space (A. Punjabi and A. Boozer, Phys. Lett. A 378, 2410 (2014)). This method is based on three elements: preservation of the two invariants—symplectic and topological neighborhood—and a new set of canonical coordinates called the natural canonical coordinates. The very complicated shape of edge surfaces can be represented very accurately and very realistically in these new coordinates (...
High-Q transverse-electric/transverse-magnetic photonic crystal nanobeam cavities

We experimentally demonstrate high quality factor dual-polarized photonic crystal nanobeam cavities. The free-standing nanobeams are fabricated in a 500 nm thick silicon layer, and are probed using both tapered optical fiber and free-space resonant scattering set-ups. We measure Q factors greater than 104 for both transverse magnetic (TM) and transverse electric modes, and observe fiber transmission drops as large as 1−T=0.8 at the TM mode resonances.
Tolloid gets Sizzled Competing with Chordin

The enigma of Sizzled, a secreted Frizzled-related protein, has been resolved in a recent study from the De Robertis lab (Lee et al., 2006 [in the January 13 issue of Cell]). Sizzled, although homologous to other Wnt antagonists, does not function as such, nor does it function within a Wnt signaling pathway. Remarkably it functions as an antagonist of BMP signaling, competing with Chordin for binding to its inhibitor a Tolloid-related metalloprotease. This competition protects Chordin from cleavage, thus allowing it to bind and limit BMP signaling.
History of pulse energization in electrostatic precipitation

Abstract The history of modern, high frequency pulse energization in electrostatic precipitation is reviewed viewed from its beginning stemming from microsecond radar pulse generator development (1941–1945) to early research and development leading to first tests on field precipitators (1947–1952), thence to later developments (1970–present) by a number of investigators in U.S.A., Europe and Japan. This work produced a variety of basic pulse energization circuits and technology used in research, development and field demonstration studies on full-size ESPs. Interest and activity in pulse energization to avoid the deleterious effects of back corona for dusts in the range 10 11 −10 13 ohm cm remains high worlwide. The tecnology has been accepted as a viable, reliable, and effective method for significantly improving the performance of existing electrostatic precipitators, and reducing the size and cost of new ESP designs treating difficult high resistivity dusts. Over 100 commercial pulsers in many countries worldwide have been installed since 1981 and are now extant for high efficiency dust collection in major industries such as cement, power generation lime kilns and steel. Pulse energization technology now centers in three major areas: pulse widths in the nanosecond range, in the nominal 1–2 μs range, and in the range 50–200 μs — the first two using spark gap switches to achieve very fast voltage rise times and the third generally using solid-state thyristor switching. Of special current interest is use of submicron high voltage pulses for pre-charging and for generating an active corona plasma for chemical reactions to remove SO 2 and NO x from boiler flue gases. A brief section on ESP fundamentals and application factors with pulse energization, as well as an extensive bibliography, are included.
The use of progestational agents for preterm birth: Lessons from a mouse model

Objective On the basis of the recent Maternal Fetal Medicine Unit Networks clinical trial, the American College of Obstetricians and Gynecologists supports the administration of 17-alpha hydroxyprogesterone caproate to high-risk patients. Because inflammation/infection is believed to be a contributing factor in many cases of preterm birth, it is imperative to understand the effect of 17-alpha hydroxyprogesterone caproate treatment in this clinical situation. Study design Using a mouse model of localized intrauterine inflammation, we investigated the ability of progestational agents to prevent preterm birth. On gestational day 15 (E15), dams were assigned randomly to treatment with 17-alpha hydroxyprogesterone caproate, medroxyprogesterone acetate, or vehicle before intrauterine infusion of lipopolysaccharide. All dams were monitored for morbidity and preterm birth. Three separate sets of experiments were performed to assess different outcomes at 6, 24, and 96 hours. At 6 and 24 hours, C-reactive protein, interleukin-6, and interleukin-10 levels were measured in maternal serum by enzyme-linked immunosorbent assay. Results Pretreatment with 17-alpha hydroxyprogesterone caproate or medroxyprogesterone acetate before intrauterine lipopolysaccharide treatment significantly decreased the preterm birth rate, compared with lipopolysaccharide treatment alone. Medroxyprogesterone acetate treatment was more effective than 17-alpha hydroxyprogesterone caproate treatment in the prevention of preterm birth and resulted in live pups at term. Treatment with 17-alpha hydroxyprogesterone caproate was associated with significant maternal morbidity. Conclusion In the setting of intrauterine inflammation, progestational agents decrease the preterm birth rate but can result in maternal morbidity. 17-Alpha hydroxyprogesterone caproate should not be used in patients who are suspected of having subclinical infection and/or acute preterm labor. The mechanisms by which progestational agents inhibit preterm birth warrants further investigations so that the use of this drug to appropriate populations could be pursued without undue fetal or maternal harm.
Absenteeism and HIV infection

We sought to determine whether employed patients with HIV infection reported more days unable to work than similar patients without HIV infection. We did not consider whether HIV infection resulted in job loss. Cross-sectional data on 884 employed patients from five physician-sites in California were drawn from the AIDS Time-Oriented Health Outcome Study (ATHOS). An econometric 2-part model with a number of covariates including age, race, education, and an instrumental variable reflecting the probability of any employment was constructed to provide a comparison between three categories of patients, HIV -negative; HIV positive but not yet AIDS; and AIDS. The results suggested no statistically significant difference between the comparison patients (HIV -negative) and the patients with HIV but not AIDS for days unable to work. Employed patients with AIDS, however, reported roughly 5.1 (one week) more days unable to work out of the prior three months than either the comparison patients or the patients with HI...
A new class of finite translation planes obtained from the exceptional near-fields

Abstract It is the purpose of this paper to construct some new finite translation planes from the exceptional (irregular) near-fields, described by Dickson and Zassenhaus. The main portion of the paper is concerned with showing that these new planes are not contained in the class of generalized Andre planes, recently discovered by Foulser. A rather general and extremely useful result, which gives a necessary condition that certain Veblen-Wedderburn systems coordinatize isomorphic translation planes, is contained in Section 7 of the paper.
Young children with specific language impairment and their numerical cognition

This study examined the enumeration and numerical reasoning levels of children with specific language impairment (SLI) compared to those of two groups of typically developing children: children mat...
Model reference adaptive control of large scale systems

Adaptive model reference procedures which do not require explicit parameter identification are considered for large scale systems. Such application is feasible provided that there exists a feed-back gain matrix such that the resulting input-output transfer function is strictly positive real. Consideration of a simply supported beam shows the positive real condition to be satisfied for velocity and velocity plus scaled positional outputs sensed at the same points where the actuators are positioned. Results show the adaptive algorithm to indeed be capable of satisfactory output model following performance with all beam states stabilized.
Stereochemistry of alkylated isoquinoline Reissert compounds

Abstract A series of alkylated isoquinoline Reissert compounds (2-acyl-1-alkyl-1,2-dihydroisoquinoline-1-nitriles) with either 3-H (3) or 3-CH3 (4) substituents was examined by 1H, 13C, and 19F NMR spectroscopies and X-ray crystallography. In all cases the trans-amide conformation, with reference to the carbonyl oxygen and the 3-position of the isoquinoline ring, exists exclusively in the solid state, and predominates in solution. As expected the 1-alkyl groups (isopropyl, isobutyl, benzyl) are nearly pseudo-axial or axial in all cases. In N-aroyl compounds the larger ortho-aroyl substituent lies syn to the 1-alkyl moiety in nine of the 11 cases, as revealed by X-ray crystallographic studies. In solution NMR results show that atropisomerism about the Ar/CO bond is usually rapid at room temperature, but slow at −50 °C and usually favors the syn isomer. CH⋯π interactions of the 3-methyl protons of 4 with the N-aroyl moieties appear to influence the atropisomerism.
Estimation of inertial parameters of rigid body links of manipulators

A method of estimating the mass, the location of center of mass, and the moments of inertia of each rigid body link of a robot during general manipulator movement is presented. The algorithm is derived from the Newton-Euler equations, and uses measurements of the joint torques as well as the measurement and calculation of the kinematics of the manipulator while it is moving. The identification equations are linear in the desired unknown parameters, and a modified least squares algorithm is used to obtain estimates of these parameters. Some of the parameters, however, are not identifiable due to the restricted motion of proximal links and the lack of full force/torque sensing. The algorithm was implemented on the MIT Serial Link Direct Drive Arm. A good match was obtained between joint torques predicted from the estimated parameters and the joint torques computed from motor currents.
Evaluation of plastic and Mylar flagging as repellents for snow geese (Chen caerulescens)

The effectiveness of white flags, black flags and Mylar streamers as visual repellents to snow geese (Chen caerulescens) was evaluated. Five farms in Cumberland and Salem counties, New Jersey served as test sites. At each farm, four 10.12 ha fields were selected randomly, and then assigned to four treatment conditions: (a) white plastic flags (one flag per 0.4 ha); (b) black plastic flags (one flag per 0.4 ha), (c) Mylar streamers (one streamer per 0.4 ha); and (d) stakes only (one stake per 0.4 ha). From 2 December 1992 to 24 March 1993, vegetation samples and goose droppings were collected in all fields. Dropping weights were significantly less in black- or white-flagged fields than they were in fields with Mylar streamers or bare stakes. Although vegetation weights tended to increase in white- or black-flagged fields (and to decrease in fields with Mylar streamers or bare stakes), there were no significant differences. The results show that white or black flags can economically and effectively deter snow geese from agricultural fields, at least when alternative grazing sites are available.
Addiction Toxin Fst Has Unique Effects on Chromosome Segregation and Cell Division in Enterococcus faecalis and Bacillus subtilis

The Fst toxin of the Enterococcus faecalis pAD1-encoded par addiction module functions intracellularly to kill plasmid-free segregants. Previous results had shown that Fst induction results in membrane permeabilization and cessation of macromolecular synthesis, but only after 45 min. Electron micrographs of toxin-induced cells showed no obvious membrane abnormalities but did reveal defects in nucleoid segregation and cell division, begging the question of which is the primary effect of Fst. To distinguish the possibilities, division septae and nucleoids were visualized simultaneously with fluorescent vancomycin and a variety of DNA stains. Results showed that division and segregation defects occurred in some cells within 15 min after induction. At these early time points, affected cells remained resistant to membrane-impermeant DNA stains, suggesting that loss of membrane integrity is a secondary effect caused by ongoing division and/or segregation defects. Fst-resistant mutants showed greater variability in cell length and formed multiple septal rings even in the absence of Fst. Fst induction was also toxic to Bacillus subtilis. In this species, Fst induction caused only minor division abnormalities, but all cells showed a condensation of the nucleoid, suggesting that effects on the structure of the chromosomal DNA might be paramount.
EXPRESSION OF AGGREGATION-PRONE RECOMBINANT PROTEINS AT LOW TEMPERATURES :A COMPARATIVE STUDY OF THE ESCHERICHIA COLI CSPA AND TAC PROMOTER SYSTEMS

Abstract The aggregation-prone fusion protein preS2–S′–β-galactosidase was used as a model system to compare the efficiencies of the IPTG-inducible tac promoter and the low-temperature-inducible cspA promoter in directing the expression of soluble recombinant polypeptides at reduced growth temperatures in Escherichia coli. At 37°C, the fusion protein was produced at high levels from the tac promoter, but aggregated quantitatively in a biologically inactive form. In contrast, little preS2–S′–β-galactosidase was synthesized from the cspA promoter at this temperature, presumably due to transcript instability. The highest yields of active enzyme were obtained following temperature downshift from 37 to 30°C for the tac promoter and 25°C for the cspA promoter. At 25°C, the kinetics of accumulation of β-galactosidase activity, ratios of soluble to insoluble fusion protein, and synthesis rates of preS2–S′–β-galactosidase were virtually identical for both promoters for a period of 2 h postinduction. Thereafter, the cspA promoter became repressed, whereas synthesis of the fusion protein continued with the tac system. Following transfer to 10°C, the tac promoter was almost completely inhibited while the cspA promoter was able to direct the synthesis of soluble preS2–S′–β-galactosidase for up to 2 h. However, the levels of active enzyme produced were approximately threefold lower than those measured at 25°C. Overexpression of native CspA had no effect on the accumulation of active preS2–S′–β-galactosidase from the cspA promoter. It is therefore unlikely that CspA acts as it own positive inducer. Our results indicate that the cspA promoter can efficiently substitute for the tac system at 25°C and may be particularly valuable for the expression of highly aggregation-prone or unstable gene products at 10°C.
A 90µW MICS/ISM band transmitter with 22% global efficiency

For fully autonomous implantable or body-worn devices running on harvested energy, the peak and average power dissipation of the radio transmitter must be minimized. We propose a highly integrated 90 µW 400MHz MICS band transmitter with an output power of 20 µW leading to a 22% global efficiency — the highest reported to date for such systems. We introduce a new transmitter architecture based on cascaded multi-phase injection locking and frequency multiplication to enable low power operation and high global efficiency. Our architecture eliminates slow phase/delay-locked loops for frequency synthesis and uses injection locking to achieve a settling time ≪ 250 ns permitting very aggressive duty cycling of the transmitter to conserve energy. At a data-rate of 200 kbps, the transmitter achieves an energy efficiency of 450 pJ/bit. Our 400MHz local oscillator topology demonstrates a figure-of-merit of 204 dB.
Determination of phosphate: Study of labile organic phosphate interference

Abstract An investigation was carried out on a newer method for the determination of inorganic phosphate which is applicable to the study of phosphate-splitting enzymes. It offers a unique advantage: after the color reagent has been added any inorganic phosphate formed cannot react with molybdenum, for the latter has been complexed by the addition of a citrate-arsenite solution and phosphate cannot compete successfully for the molybdate. This procedure appears to be quite suitable for the determination of inorganic phosphate, phospholipids, nucleotides or enzyme-hydrolyzed phosphate.
PASAP: power aware structured ASIC placement

Structured ASICs provide an exciting middle ground between FPGA and ASIC design methodologies. Compared to ASIC, structured ASIC based designs require lower non recurring engineering (NRE) costs and turn-around-time but suffer from higher power consumption and lower performance. Power reduction for structured ASICs uses extensive clock and supply power-down of unused circuitry and use of low power devices. However, due to the limited granularity of power-down, physical design (specially placement) should be performed to maximize the components that can be powered down. In this paper, we present the first placement algorithm to specifically target this problem. Our tool, PASAP (Power Aware Structured ASIC Placement), minimizes the clock and leakage power by maximizing the fraction of the structured ASIC that can be powered down or disconnected from clock tree. On a set of large benchmark designs, PASAP reduces clock and leakage power by 32% and 17% respectively compared to prior structured ASIC placement tool RegPlace [1] incurring 17% penalty in wirelength and 30% longer runtime.
Pneumocystis carinii Pneumonia Prophylaxis During Pregnancy

The frequency of human immunodeficiency virus (HIV) infection among pregnant women is increasing. Pneumocystis carinii pneumonia (PCP) is the most common opportunistic infection in HIV-infected patients, and prophylaxis is an important part of decreasing morbidity. Trimethoprim-sulfamethoxazole (TMP-SMX), pentamidine, and dapsone, alone or in combination with pyrimethamine, are the most commonly used drugs for PCP prophylaxis in the nonpregnant HIV-infected population. Trimethoprim-sulfamethoxazole, however, has the potential for adverse effects in the fetus. Limited data are available for the other agents administered as prophylaxis of PCP.