cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of isoflurane concentration on the activity of pontomedullary raphe and medial reticular neurons in the rat.

Abstract Neurons in the pontomedullary raphe magnus (RM) and adjacent nucleus reticularis paragigantocellularis pars α (NRPGα) are thought to participate in the modulation of spinal nociceptive transmission. In order to determine whether these cells also contribute to the suppression of nocifensive reflexes produced by general anesthetics, the spontaneous activity of RM/NRPGα cells was recorded in rats anesthetized with isoflurane (IF) at several steady state concentrations, corresponding to depths which are below, equal to, or above the threshold for blocking the motor response to noxious stimuli (minimum alveolar concentration, MAC). Neurons were classified by their spontaneous activity patterns and their responses to noxious stimulation as OFF, ON, REGULAR or NEUTRAL cells. After cell classification, unit activity, arterial blood pressure, heart rate, and EEG activity were simultaneously recorded, in the absence of somatic stimulation, for 1 h at each of two or three concentrations of IF. The concentrations tested were low (1.05–1.25%), medium (1.30–1.45%) and high (1.70–1.90%). ON, OFF and some NEUTRAL cells exhibited alternating periods of inactivity and activity when recorded during periods of low and medium anesthetic concentrations. At high steady state anesthetic concentrations, the mean discharge of most OFF, ON and NEUTRAL cells decreased by greater than 25% from their mean discharge rate at the low concentration. REGULAR cells maintained a uniform firing rate at all steady state anesthetic concentrations studied. Since high concentrations of IF do not activate OFF cells, the putative inhibitory output neuron of the RM/NRPGα, it is unlikely that the activity of RM/NRPGα neurons contributes to the suppression of nocifensive movement by the general anesthetic, IF.
Calculation of Post-Closure Natural Convection Heat and Mass Transfer in Yucca Mountain Drifts

Natural convection heat and mass transfer under post-closure conditions has been calculated for Yucca Mountain drifts using the computational fluid dynamics (CFD) code FLUENT. Calculations have been performed for 300, 1000, 3000, and 10,000 years after repository closure. Effective dispersion coefficients that can be used to calculate mass transfer in the drift have been evaluated as a function of time and boundary temperature tilt.
Computerized comprehensive numerical data system on the thermophysical and other properties of materials established at CINDAS/Purdue University

A computerized materials properties numerical data system has been developed and established at the Center for Information and Numerical Data Analysis and Synthesis (CINDAS) of Purdue University, which is a comprehensive, one-line, interactive, menu-driven, user-friendly, expert data system. This data system contains both critically evaluated reliable reference data and experimental data on the thermophysical, mechanical, electrical, optical, and other properties of various types of materials. It permits both the search of data and information for specified materials and properties and the search for materials that meet a set of requirements specified by the user (i.e., computer-aided materials selection). It permits also the on-line functional manipulation, statistical analysis, and mthemtical study of the retrieved data. The development, operation, functions, scope, contents, and other features of the data system are presented and discussed.
On the E- and MV-optimality of spring balance designs with string property

Abstract In this paper we consider the problem of optimally measuring the distances between p + 1 objects which are fixed in position along a line. It is assumed throughout that n measurements are to be taken on the distances between various pairs of objects occurring along the line. Such a problem gives rise to p × n design matrices whose entries are all 0's and 1's with the string property, i.e., the property that each row of the design matrix contains only strings of 0's and 1's. Here we develop some methods for constructing designs which are E-optimal and MV-optimal for estimating the p distances of interest.
Consecutive lymphoma with monoclonal gammopathy in a married couple

Mixed cellularity Hodgkin's disease and diffuse non-Hodgkin's lymphoma, mixed cell type, occurred consecutively in a husband and wife. Both patients demonstrated monoclonal IgM gammopathies. The unusual nature and possible significance of these findings are discussed.
Design and Calibration of a Flowfield Survey Rake for Inlet Flight Research

Flowfield rake was designed to quantify the flowfield for inlet research underneath NASA DFRC s F-15B airplane. Detailed loads and stress analysis performed using CFD and empirical methods to assure structural integrity. Calibration data were generated through wind tunnel testing of the rake. Calibration algorithm was developed to determine the local Mach and flow angularity at each probe. RAGE was flown November, 2008. Data is currently being analyzed.
Thin-layer chromatographic and spectroscopic characterization of some diterpenes of the grayanotoxin type

Abstract In a study of toxic polyhydroxylated andromedane diterpenoids, several novel derivatives of grayanotoxin III are described. Their spectral and physical characteristics are compared to ericaceous natural products. Separations on aluminium oxide and silica gel indicated that the absorption affinity of hydroxy groups on the perhydroazulene carbon skeleton was in teh order of 14γ-OH > 3β-OH > 6β-OH > 2α-OH. Partition chromatography using ethylene glycol as stationary phase exhibited migration largely in accordance with Reversed Traube's rule. This chromtographic-spectroscopic combination procedure is suitable for the micro-screening of these toxins.
Two Taylor-series approximation methods for nonlinear mixed models

Abstract This paper considers a general class of nonlinear mixed models (NLMMs). In view of the often difficult numerical integrations involved in a full likelihood analysis of general NLMMs, we discuss two approximate inference procedures, both based on Taylor-series approximations to the integrated likelihood. The two methods differ in the Taylor-series expansion point for the random-effects parameters: the first method expands around zero (the expected value of the random effects) and the second around their empirical best linear unbiased predictors (EBLUPs). We present new algorithms for implementing both approximations and relate them to existing algorithms. Finally, we assess the performance of both methods through simulation, and conclude that the EBLUP-expansion method offers minor gains in accuracy over the zero-expansion method at the cost of higher computing times and instability.
Integration of form and motion within a generative model of visual cortex

One of the challenges faced by the visual system is integrating cues within and across processing streams for inferring scene properties and structure. This is particularly apparent in the inference of object motion, where psychophysical experiments have shown that integration of motion signals, distributed across space, must also be integrated with form cues. This has led several to conclude that there exist mechanisms which enable form cues to 'veto' or completely suppress ambiguous motion signals. We describe a probabilistic approach which uses a generative network model for integrating form and motion cues using the machinery of belief propagation and Bayesian inference. We show, using computer simulations, that motion integration can be mediated via a local, probabilistic representation of contour ownership, which we have previously termed 'direction of figure'. The uncertainty of this inferred form cue is used to modulate the covariance matrix of network nodes representing local motion estimates in the motion stream. We show with results for two sets of stimuli that the model does not completely suppress ambiguous cues, but instead integrates them in a way that is a function of their underlying uncertainty. The result is that the model can account for the continuum of bias seen for motion coherence and perceived object motion in psychophysical experiments.
Interrelationships between serum levels of amiodarone, desethylamiodarone, reverse T3 and the QT interval during long-term amiodarone treatment

The interrelationships between serum levels of amiodarone, desethylamiodarone, and reverse T3, and changes in the corrected QT interval (delta QTc) were examined in 22 patients during long-term treatment with amiodarone. At 1, 3, and 6 months of follow-up, the correlation coefficient between serum levels of amiodarone or desethylamiodarone and reverse T3 ranged from 0.01 to -0.2 (p greater than 0.4). At the same time intervals, the correlation coefficient between both amiodarone and desethylamiodarone levels and delta QTc ranged from 0.1 to -0.1 (p greater than 0.6), and the correlation coefficient between reverse T3 and delta QTc also ranged between 0.1 to -0.1 (p greater than 0.5). Substituting percent delta QTc for delta QTc also did not reveal a significant correlation. These data demonstrate that serum levels of reverse T3 cannot be used as a substitute for serum levels of amiodarone in monitoring patients being treated with amiodarone. The absence of a correlation between serum reverse T3 levels and delta QTc suggests that the delay in repolarization which occurs during amiodarone therapy is not secondary to an amiodarone-induced abnormality in thyroid hormone metabolism.
The utility of the Angstrom-type equation for the estimation of global irradiation

L'auteur affirme que l'equation de type Angstrom fournit la meilleure estimation de l'eclairement global
Experimental measurements of dielectric relaxation in glass

Abstract The measurement and theory of dielectric relaxation in glass are discussed. It is shown that contacting electrodes such as Ag paste or Au sputtered film can lead to anomalously high dielectric losses and high capacitance, but the use of stainless steel electrodes reduces these losses and capacitances substantially. The height of the loss peak was proportional to the sample thickness for a sodium silicate glass. Broad, asymmetric loss peaks were found for different glasses. The results are compared to equations derived from a space-charge model. These equations predict the thickness dependence found and also the shapes of some of the loss peaks. Predictions of the frequency of maximum loss are in fair agreement with experimental data.
A comparison of the characteristics of soluble organic nitrogen in untreated and activated sludge treated wastewaters

Soluble organic materials containing nitrogen (SON) are present in effluents from activated sludge treatment of domestic wastewater, but little is known about the sources and characteristics of these materials. The objective of this research was to evaluate the characteristics of SON in untreated wastewaters and activated sludge effluents. Characterization techniques used included low microbial seed biodegradability, molecular weight distribution using gel filtration chromatography, removal by activated carbon and ion exchange, and analysis for free and combined amino acids. Activated sludge effluent SON was more refractory (40–50%; first-order decay rates for the remainder were about 0.014 day−1 than SON in untreated wastewater (18–38%; decay rates for the remainder were 0.08–0.16 day−1). SON produced biologically during treatment had decay rates (about 0.028 day−1) similar to SON in municipal activated sludge effluents, and was from 20 to 100% refractory. Less than 10% of the SON in municipal activated sludge effluent consisted of free or combined amino acids. Approximately 15–30% appeared to nucleic acid degradation products. Fifty to 60% of the SON and SCOD had apparent molecular weights of less than 1800. Apparent molecular weight distributions of treated and untreated wastewaters were similar; however, the excess SON produced during activated sludge start-up contained considerably more SON with molecular weights greater than 1800. The 165–340 molecular weight fraction had a significantly higher SON to SCOD ratio than any other fraction for all wastewaters examined. Activated carbon adsorption efficiently removed SON (72 ± 9%) and SCOD (78 ± 6%) from treated and untreated wastewaters, and from biologically produced organics. Significantly more SON was removed by cationic exchange at pH 2.0 (33–56%) than by anionic exchange at pH 9.5 (10–24%) for all wastewaters tested. Cationic exchange at pH 2.0 selectively removed more biologically produced SON relative to SCOD.
Influence of Procedural Learning on Iowa Gambling Task Performance Among HIV+ Individuals with History of Substance Dependence

HIV+ individuals have been shown to demonstrate deficits on the Iowa Gambling Task (IGT), a complex measure of “decision-making.” Little remains known about what other neurocognitive processes may account for variability in IGT performance among HIV+ samples or the role of procedural learning (PL) in IGT performance. A sample of 49 HIV+ individuals with a history of substance use disorders was examined to explore the relationship between IGT performance and three measures of PL: The Rotary Pursuit, Mirror Star Tracing, and Weather Prediction tasks. We found no statistically significant relationships between IGT performance and any of the PL tasks, despite finding significant correlations among the PL tasks. This pattern of results persisted when analyzing IGT performance in various ways (e.g., performance on earlier trial blocks or impairment classifications). Although other nondeclarative processes (e.g., somatic markers) may be important for IGT performance, these findings do not support PL as an important component neurocognitive process for the IGT. Similarly, these results suggest that differences in PL performance does not account for the decision-making deficits or variability in performances observed on the IGT among HIV+ individuals with a history of substance dependence.
TNFα and IL-1β mediate intercellular adhesion molecule-1 induction via microglia–astrocyte interaction in CNS radiation injury

Radiation injury to the central nervous system (CNS) results in glial activation accompanied by expression of pro-inflammatory cytokines and adhesion molecules. In this study we demonstrate intercellular adhesion molecule-1 (ICAM-1) induction in the irradiated mouse brain at the mRNA and protein levels. Immunocytochemical analysis revealed that ICAM-1 protein was primarily expressed in endothelial cells and microglia. In vitro, ionizing radiation significantly induces TNF alpha, IL-1beta and ICAM-1 mRNA in primary microglia cultures. Interestingly, although ionizing radiation activated primary astrocyte cultures, it did not induce ICAM-1 expression. However, exposure of astrocytes to conditioned medium collected from irradiated microglia resulted in ICAM-1 induction, which was abrogated when the conditioned medium was pre-incubated with neutralizing antibodies raised against murine TNF alpha and IL-1beta. These results indicate that pro-inflammatory cytokines may be necessary for ICAM-1 expression in astrocytes in CNS radiation injury.
Coupling sequences flanking Tn916 do not determine the affinity of binding of integrase to the transposon ends and adjacent bacterial DNA.

Coupling sequences are the 6 bp flanking the conjugative transposon Tn916 and are thought to play a role in determining the frequency of conjugative transposition. The affinity of binding of a chimeric protein, which consisted of maltose binding protein fused to the carboxy-terminal DNA binding domain of Tn916 integrase (Int), to different double-stranded oligonucleotide substrates containing coupling sequences associated with high- and low-frequency conjugative transposition was measured using a competition binding assay. The relative affinity of the chimeric protein was unaffected by the nature of the coupling sequences tested. The same results were obtained when the coupling sequences were placed in a different surrounding sequence context. It therefore appears that the effects of different coupling sequences on the frequency of conjugative transposition are not due simply to differences in Int binding.
Hadamard coded modulation: An alternative to OFDM for wireless optical communications

Orthogonal frequency division multiplexing (OFDM) is a modulation technique susceptible to source, channel and amplifier nonlinearities because of its high peak-to-average ratio (PAPR). The distortion gets worse by increasing the average power of the OFDM signals since larger portion of the signals are affected by nonlinearity. In this paper we introduce Hadamard coded modulation (HCM) that uses the fast Walsh-Hadamard transform (FWHT) to modulate data as an alternative technique to OFDM in direct-detection wireless optical systems. This technique is shown to have a better performance for high average optical power scenarios because of its small PAPR, and can be used instead of OFDM in two scenarios: 1) in optical systems that require high average optical powers such as visible light communications (VLC), and 2) in optical wireless systems unconstrained by average power, for which HCM achieves a lower bit error rate (BER) compared to OFDM. The power efficiency of HCM can be improved by removing a part of the signal's DC bias without losing any information. In this way, the amplitude of the transmitted signal is decreased and the signals become less susceptible to nonlinearity. Interleaving can be applied on HCM to make the resulting signals resistent against inter-symbol interference (ISI) effects in dispersive channels by uniformly distributing the interference over all symbols.
Radioactive isotopes of Sr, Y and Zr

Radioactive isotopes formed by bombardment of Rb, Sr and Y by protons, deuterons and neutrons are reported. The following are the periods and assignments: 2.75-hr. (Sr87*, e-, γ); 70-min. (Sr85, e-, γ); 66-day (Sr85, K, γ); 80-hr. (Y87, K); 14-hr. (Y87, e-, γ); 105-day (Y86, K, γ); 4.5-min. (Zr89, γ); 78-hr. (Zr89, β+). (In each case e- means conversion electrons, not nuclear β-rays.) The electron spectrum of the 2.75-hr. Sr87* shows a single line at 360 kev and this period is shown to grow from the 80-hr. Y87, but not from the 14-hr. isomer.
WHY DO QUANTUM THEORISTS IGNORE THE QUANTUM THEORY

INTRODUCTIONS to quantum theory usually begin with a description of the (alleged) dual nature of matter, sometimes displaying particle and at other times wave qualities, as (allegedly) evidenced by electronic diffraction experiments. Atomic phenomena are said to give us the ' epistemological lesson' that we must abandon the search for a realistic unitary theory of matter and be satisfied with two complementary pictures, none of them claiming to represent any true constitution of matter. We thus have to 'renounce' objective realism in favour of'dialectical positivism' and introduce a new 'Copenhagen language'. (The terms in quotation marks are standard expressions of the 'new physics'.) This 'quantum theory of knowledge', established around 1930 by Bohr and Heisenberg, has influenced a whole generation of physicists and is recommended as late as 1963 by L. Rosenfeld1 in the following passage:
Remote Sensing: The Next 50 Years

Remote sensing is viewed as a complete system for observing and managing man's environment on Earth. The sensing portion of the system consists of space, air, and ground observing platforms, sensors, communications, computational capabilities and interpretation, and recognition algorithms. The data are put to use using environmental models, geographic information systems, and management models. Progress and potentials in each of these system elements are reviewed and projected. Existing and potential uses are sketched and certain institutional, diplomatic, and national security issues are identified. Some underlying reasons for belief in continued progress are mentioned and the need for certain crucial choices in the future stated which will determine which of a number of possible futures will be realized.
Analytic Reviews : Potential New Therapies for Acute Ischemic Stroke

Evidence from animal models of acute stroke suggests ischemia may be reversible if blood flow is restored in the first few hours. Studies of human stroke using posi tron emission tomography demonstrate areas with re duced blood flow and relatively preserved metabolism, indicating potentially reversible ischemic brain. Resto ration of blood flow during this reversible phase should improve outcome after stroke.Many therapeutic strategies for treatment of acute ischemic stroke have been proposed, including increas ing collateral flow, removing vascular obstructions, and interfering with the intracellular cascade of events that lead to neuronal cell death. Hypervolemic hemodilution reduces viscosity and increases cerebral blood flow, and this may hopefully raise blood flow above the critical threshold of irreversible ischemia. Naloxone, calcium channel blockers, and glutamate antagonists alter blood flow and influence intracellular events during and after acute ischemia. Thrombolytic therapy restores blood fl...
Cytogenetic Characteristics of Cell Lines from Ixodes scapularis (Acari: Ixodidae)

Three new cell lines, IDE8 and IDE12 from embryos of northern specimens of Ixodes scapularis Say and ISE18 from southern specimens of I. scapularis, were compared cytogenetically via conventional karyotyping, C- and G-banding, and nucleolar organizing regions (NORs). The karyotypes were very similar. The standard karyotype in the three cell lines consisted of 28 chromosomes with 26 autosomes and XX (female) or XY (male) sex chromosomes. The X chromosome was the largest, and the Y chromosome the smallest chromosome of the karyotype. Constitutive heterochromatin (C-bands) was almost entirely restricted to the centromeric region. An additional interstitial C-band in chromosome 7 was an important notable characteristic of the three cell lines. In sets showing a similar degree of condensation, individual chromosomes of the three lines had identical G-banding patterns. In addition, there was no difference among the cells in number and position of NORs. There were approximately 100 G-bands per haploid set in chromosomes from cells in metaphase, with three to 18 G-bands in each chromosome arm. After staining with silver nitrate, interstitial NORs were identified in chromosomes 7, 10, and the X chromosome. Male cells had five and female cells had six NORs. These findings support the notion that I. scapularis and I. dammini Spielman et al. are conspecific.
Sites of origin of gonadotropin releasing hormone containing projections to the amygdala and the interpenduncular nucleus

Abstract The sites of origin of gonadotropin releasing hormone (GnRH) containing projections to the amygdala and the interpenduccular nucleus were studied with immunofluorescence for GnRH in combination with retrograde transport of True blue. After small injections of True blue into the amygdala, retrogradely labeled GnRH producing neurons were identified in the rostral medial septum, the caudal roots of the nervus terminalus, diagonal band, nucleus triangularis septi, nucleus interstitialis striae terminalis, and in the ventrolateral hypothalamus. After injection of True blue into the interpendicular nucleus, a small GnRH producing cell group in the ventro-medial diagonal band, and certain GnRH-positive neurons in the ventral hypothalamus had retrogradely transported the dye. The results suggest a link between the amygdala and the nervus terminalis which is provided in part by GnRH-containing projections. The heterogeneity of the sites of origin of inputs to the amygdala and the interpenduncular nucleus indicates that the ‘behavioral’ component of the GnRH system is not restricted to a single brain nucleus, but it may be part of a diffuse network which has close anatomical ties with the ‘endocrine’ GnRH system.
The use of the “puffed‐cheek” computed tomography technique to confirm the diagnosis of pneumoparotitis

Pneumoparotitis is a rare etiology of symptomatic parotid gland enlargement that is often misdiagnosed clinically. Pneumoparotitis results from air refluxing into the parotid ductal system via an incompetent Stensen duct orifice. We report a protracted case of pneumoparotitis evaluated with the "puffed-cheek" computed tomography technique to help confirm the diagnosis.
The Mössbauer properties of epitaxial Fe-bcc Ni multilayers

Abstract Two series of Fe(110)/[bcc Ni] and Fe(100)/[bcc Ni] heterostructures were grown by molecular beam epitaxy. Analysis of the multilayers with 57 Fe Mossbauer spectroscopy indicated that all of the film's local magnetization directions were oriented in-plane, and revealed that the spectra of both multilayer series consisted of two slightly broadened sextet components, corresponding to interface and interior Fe bilayer sites. The interior sites had slightly enhanced ground state hyperfine field values compared to bulk, while the interfacial sites had reduced ground state hyperfine field values. SQUID magnetometry revealed that the typical film coercivity of the Fe(100)/Ni was approximately an order of magnitude greater than that observed for the Fe(110)/Ni series.
Chlorpropamide effect: Measurement of neurophysin and vasopressin in humans and rats☆

The effect of chlorpropamide on neurohypophyseal function was studied by measurement of neurophysin and vasopressin in humans and in rats. Administration of chlorpropamide was shown to inhibit the ability of the human subjects and of the rats to maximally dilute their urine after administration of water. Comparison of the levels of vasopressin and neurophysin before and after the administration of chlorpropamide in the basal state and after water loading in both the human subjects and in rats showed no lack of suppression due to the chlorpropamide. The levels of both peptides were measured at the limits of detection. In other studies where neurophysin and vasopressin were readily detected, administration of chlorpropamide did not result in any augmented release of neurophysin or vasopressin in response to stimulation of the neurohypophysis in humans nor in rats. Levels of neurophysin in the pituitaries of rats showed no change in rats given chlorpropamide, while the content of vasopressin was increased, possibly indicating a chronic decreased secretion of vasopressin in rats given chlorpropamide.
Actions of RU 38486 on progesterone facilitation and sequential inhibition of rat estrous behavior: Correlation with neural progestin receptor levels

The present study examined the actions of the antiprogestin RU 38486 on progesterone (P)-induced facilitation and sequential inhibition of estrous behavior and on brain cytosol progestin receptor (PR) levels in ovariectomized, estrogen-primed (0.5 micrograms of estradiol benzoate for 3 days) female rats. RU 38486 suppressed P-facilitated receptive and proceptive responses in a dose-dependent fashion when administered 1 hr prior to P. RU 38486 did not, however, block the sequential inhibitory effect of P. Indeed, when it was administered alone at a dose of 1 mg, animals were rendered behaviorally unresponsive to a P treatment 25 hr later. It is unclear whether RU 38486 is an agonist for P sequential inhibition of estrous behavior or if the apparent agonist action of RU 38486 actually results from a long-term antagonist effect. Estrogen-induced PRs remain elevated (35-55% above basal) in the hypothalamus (HYP) and preoptic area (POA) at 24 and 48 hr following the last estrogen injection. Thus P facilitation of estrous behavior is correlated with increased levels of cytosol PRs. RU 38486 reduced cytosol PRs in both brain regions to basal levels within 2 hr, and the levels remained suppressed 25 hr following the treatment. Hence there is a strong correlation between behavioral inhibition and suppressed cytosol PRs at both short (5 hr) and long (25 hr) intervals after RU 38486 administration. A P treatment which produced sequential inhibition of estrous responsiveness 24 hr later did not reduce the estrogen-induced level of cytosol PRs in either brain region. These results suggest that mechanisms in addition to induction of PRs may be necessary to ensure successful mating.
Star formation in galaxies between redshifts of 0.7 and 1.8

We present an analysis of the star formation rate in galaxies with redshifts in the range 0.7 < z < 1.8 using Near Infrared Camera and Multi-Object Spectrograph (NICMOS) grism spectral observations. We detect 163 galaxies in an area of ~4.4 arcmin2, 37 of which show possible H? emission. We extend the observed H? luminosity function (LF) in this redshift range to luminosities a factor of 2 fainter than earlier work and are consistent in the region of overlap. Using the H? LF, we estimate a star formation rate (SFR) density in this redshift range of 0.166 M? yr-1 Mpc-3 (H0 = 75 km s-1 Mpc-1), consistent with other estimates based on emission lines and supporting the order-of-magnitude increase in SFR density between z = 0 and z = 1. Our measurement of SFR density is a factor of ?2?3 greater than that estimated from UV data, comparable to the factor observed locally, implying little evolution in the relative extinctions between UV and H? out to z ? 1.3.
Combined effects of concave and convex nonlinearities in elliptic equation on RN

Abstract In this paper we consider the existence of two positive solutions of the elliptic equation on R N with concave and convex nonlinearities.
Laser‐Raman spectroscopy of biomolecules. XI. Conformational study of poly(L‐valine) and copolymers of L‐valine and L‐alanine

Raman spectroscopic studies have been carried out on polymers of L-valine ranging in degree of polymerization (DP) from 2 to 930. The spectrum of the hexapeptide (DP = 6) is closely similar over the entire range 40–1750 cm−1 to those of polymers with much higher DP, and the structure is clearly shown to be that of the antiparallel pleated sheet (β-structure) by the amide I and III frequencies. The formation of a little α-helical structure occurs in polymers with DP above 500, although the amount does not appear to be a linear function of DP. The α-helical structure is unstable and readily destroyed in samples cast from trifluoroacetic acid solution. It is stabilized by the incorporation of L-alanine, a strong helix-former; polymers of the latter may in turn be forced into a α-structure in copolymers sufficiently rich in L-valine.
Effect of Tetracycline on Crystal Growth

IN a previous investigation1, it was shown that when the larvae of the sand-dollar E. parma were reared in sea-water containing low concentrations of tetracycline, the fluoro-phore was incorporated into the growing skeleton. At higher concentrations, reduction or failure of the formation of skeletal elements resulted. Further, the addition of calcium to the sea-water–tetracycline mixtures in excess of the theoretical amount with which tetracycline could combine, failed to prevent inhibition of mineralization. Several additional investigations carried out by my colleagues and me have demonstrated that administration of tetracycline to organisms producing skeletal elements results in hypomineralization of bones2 and teeth3. In an attempt to elucidate the mechanism of hypomineralization in greater detail, we selected as a test object the regenerating shell of the marine mollusc Pinna, in which the regenerating portion of the shell consists of large calcite crystals.
A prospective analysis of the influence of gestational age on the baseline fetal heart rate and reactivity in a low-risk population

Abstract The nonstress test is of recognized value for the antepartum assessment of fetal well-being. Less well defined, however, is the relationship between baseline fetal heart rate, reactivity, and the gestational age of the fetus. A prospective analysis of the nonstress test in a preterm, low-risk population was begun. Weekly tests were begun as early as 23 weeks and continued to term. A test was considered reactive if there were two or more fetal heart rate accelerations within a 20-minute period. A total of 128 nonstress tests were performed on 25 low-risk patients. Of these tests, 84 (64%) were considered reactive. With advancing gestational age, a progressive increase in the incidence of reactive tests was observed. However, no significant difference in baseline fetal heart rate could be identified between term and pretem fetuses. In addition, the frequency and amount of accelerations and decelerations were determined. Decelerations were not noted more frequently in the preterm population. Conversely, accelerations occurred more frequently with advancing gestational age. The pregnancy outcome was excellent for all study patients. It is concluded, therefore, that with advancing gestational age more reactive nonstress tests are seen. Baseline fetal heart rate and the frequency of decelerations appear to be unaffected by advancing gestational age. Finally, although the numbers are small, the nonstress test appears to be a suitable technique for assessing fetal well-being in the preterm fetus.
The application of cultural and social capital: a study of the 25th year reunion entries of prep school and public school graduates of Yale College

This article compares the post-college experiences of graduates of elite prep schools, non-elite prep schools and public schools who attended Yale College in the early 1960s. Drawing on previous research, and on Bourdieu's theory of social reproduction, it was hypothesized that Yale graduates who had attended public secondary schools would be more likely than Yale graduates who had attended prep schools to accumulate what Bourdieu calls ‘cultural capital,’ but that Yale graduates who had attended prep schools would be more likely than their public school counterparts to accumulate what Bourdieu calls ‘social capital.’ A study of the life experiences of the Yale College class of 1963 during the 25 years after their college graduation supported this general expectation. There was also support for a series of more specific expectations about post-graduate educational achievement, occupational choices, and behavioral indices of loyalty to Yale.
Smoking withdrawal symptoms in response to a trauma-related stressor among vietnam combat veterans with posttraumatic stress disorder

Abstract This study investigated the relationship between a trauma-related stressor and smoking withdrawal symptoms in 25 male Vietnam combat veterans with posttraumatic stress disorder (PTSD) using a within-subjects design. All subjects were smokers. The stressor involved a modified Stroop task, in which the veterans color-named either anxietyrelated or neutral control words. Anxiety-related words produced more withdrawal symptoms than neutral control words, including increased craving, negative affect symptoms, somatic symptoms, and lack of alertness.
Novel Role for Protein Kinase G Oxidative Activation in the Vasodilator and Antihypertensive Actions of Hydrogen Sulfide

See related article, pp 1344–1351 In this issue of Hypertension , Stubbert et al1 provide evidence for the novel concept that activation of protein kinase G-1α (PKG) by a cyclic GMP–independent thiol oxidation–mediated dimerization (which cross links its 2 subunits by a disulfide bond) is an important factor in the vascular relaxing and blood pressure–lowering effects of hydrogen sulfide (H2S). The attenuation of H2S responses in a mouse knockin model having the cysteine-42 redox sensor involved in disulfide-mediated subunit dimerization of PKG replaced with a redox-dead serine-42 previously developed by this group,2 together with evidence for H2S promoting PKG activation by this mechanism, provides rather compelling evidence for PKG signaling participating in the vasodilator actions of H2S. Experiments in aqueous buffer provide novel evidence that polysulfides (such as HSSH, HSSSH, etc) can catalyze the disulfide needed for dimerization of the subunits of PKG, even in the presence of much larger physiological concentrations of the thiol glutathione. Polysulfides are shown to be derived in buffer from either the slow oxidation of H2S by oxygen or the relatively rapid oxidation of H2S by hydrogen peroxide (H2O2), potentially through the formation of sulfenic acid (HSOH, HSSOH, etc) intermediates. These novel observations suggest that PKG activation by this cyclic GMP–independent mechanism needs to be considered in the actions of H2S because previous studies on cyclic GMP–mediated PKG signaling in vascular tissue3 suggest that many of the systems regulated by H2S4 are also known to be controlled by PKG. Evidence suggesting the importance of redox regulation of PKG in the actions of H2S raises …
Alcohol, allopregnanolone and aggression in mice.

Rationale: Aggressive behavior of certain individual animals can be greatly increased when under the influence of low doses of alcohol. One of alcohol's neurochemical actions that may be relevant to alcohol-heightened aggression (AHA) is its positive modulation of the GABAA receptor complex. Objective: The objective of this study was to investigate whether alcohol interacts with an endogenous modulator of the GABAA receptor complex, the neurosteroid allopregnanolone, in stimulating/heightening aggressive behavior. Methods and results: The first experiment was designed to test the hypothesis that neurosteroid modulators of the GABAA receptor complex will increase aggression and to compare these effects with alcohol. Male CFW mice were injected with allopregnanolone, alphaxalone (3–30 mg/kg, IP), or alcohol (1.0 g/kg, PO) 15 min prior to a 5-min confrontation with an intruder. Moderate doses of alcohol and the neurosteroids increased aggression by ca. 50% above baseline; impaired locomotion was seen only at the highest doses. A second experiment compared AHA and ANA (i.e. alcohol-non-heightened aggression) mice by giving allopregnanolone (1–10 mg/kg) with a simultaneous oral injection of alcohol (0.6 or 1.0 g/kg) or water. When administered with water and the 0.6 g/kg dose of alcohol, allopregnanolone increased the aggression of AHA and ANA mice. Administration of the 1.0 g/kg dose of alcohol in ANA mice prevented allopregnanolone-heightened aggression. In AHA mice, addition of allopregnanolone to 1.0 g/kg alcohol dose-dependently reduced alcohol-heightened aggression, suggesting potentiation of alcohol's suppressive effects on aggression. Conclusions: The neuroactive steroid allopregnanolone appears to play an important role in alcohol-heightened aggression. Moreover, the upward shift of the aggression-heightening effects of alcohol and the downward shift at the maximally effective alcohol dose by allopregnanolone point to a shared mechanism for both positive modulators of the GABAA receptor complex.
Calcium store depletion potentiates a phosphodiesterase inhibitor- and dibutyryl cGMP-evoked calcium influx in rat pituitary GH3 cells

A role for cGMP in the control of capacitative Ca2+ influx was identified in rat pituitary GH3 cells. Application of 50 microM - 1 mM of the non-specific phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine (IBMX), or the specific cGMP-phosphodiesterase inhibitor, zaprinast, induced a dose-dependent increase in the intracellular free Ca2+ concentration [Ca2+]i of the pituitary cell line, as assessed by video ratio imaging using fura-2. Response onset times were identical and response profiles were similar in all cells analysed. Application of 50 microM dibutyryl cGMP to GH3 cells resulted in heterogeneous Ca2+ responses, consisting of single or multiple transients with varying onset times. In all cases, increases in [Ca2+]i were predominantly due to Ca2+ influx, since no responses were detected in low Ca2+ medium, or following pre-incubation of cells with 1 microM verapamil, or nicardipine. Depleting intracellular Ca2+ stores by prior treatment of cells with 1 microM thapsigargin resulted in a dramatic potentiation in the Ca2+ influx mediated by both phosphodiesterase inhibitors and dibutyryl cGMP, suggesting that cGMP modulates a dihydropyridine-sensitive Ca2+ entry mechanism in GH3 cells which is possibly regulated by the state of filling of Ca2+ stores.
Changes in the isotype composition of β-tubulin delivered to regenerating sensory axons by slow axonal transport

Abstract β-Tubulin is encoded by a family of genes that produces at least five distinct polypeptide isotypes in neurons. Two of these isotypes (i.e., classes II and III) preferentially accumulate in axons, and the expression of one of them (i.e., class II) correlates closely with axonal outgrowth during development and regeneration. In dorsal root ganglion (DRG) neurons, expression of the class II isotype declines to relatively low levels during early postnatal development, and increases dramatically in mature neurons during axon regeneration (i.e., to a level comparable to that in developing neurons). In contrast, expression of the class III isotype, which rises slightly during postnatal development, increases much less than the class II isotype during regeneration. We now document that these changes in gene expression are associated with an increase in the relative amount of class II as compared to class III β-tubulin delivered to regenerating sensory axons of rat sciatic nerve by slow axonal transport. In this study, the tubulin transported in sensory axons was labeled by injecting [ 35 S]methionine into the L5 DRG either 7 or 14 days after crushing the sciatic nerve; pulse-labeled class II and class III β-tubulin were identified using immunoprecipitation. This change in the isotype composition of β-tubulin transported in regenerating axons may influence outgrowth by altering the assembly and dynamic properties of axonal microtubules.
Casein micelles partially hydrolyzed by chymosin to modify the texture of lowfat ice cream

Abstract Lowfat (2%) ice cream was prepared from mixes that were subjected to limited proteolysis with chymosin. The mix was treated with either .64 or .85 IMCU (international milk-clotting units) of chymosin/kg of mix for 15min at 60°C; the chymosin was derived by fermentation and is commercially available. Chymosin was inactivated by holding the mix at 63.3°C for 30min. Treated mixes were aged overnight at 4°C, and ice cream (80 to 90% overrun) was produced using conventional techniques. Following chymosin treatment, mix viscosity was significantly increased. Analysis by a trained sensory panel revealed that ice cream made with the chymosin-treated mix had increased hardness, smoothness, cohesiveness, mouthcoating, and mouthdrying characteristics. Treated ice cream was judged by the panel to have a slower rate of melting, decreased adhesiveness, and less graininess than the control. These characteristics were more pronounced for ice cream made with .85 IMCU of chymosin/kg of mix. The difference between treated and untreated ice cream was not as apparent when the finished product was stored for 7 d at –15°C rather than –30°C.
The risks and benefits of HPV vaccination.

HEN DO PHYSICIANS KNOW ENOUGH ABOUT THE beneficial effects of a new medical interventiontostartrecommendingorusingit?When istheavailableinformationaboutharmfuladverse effects sufficient to conclude that the risks outweigh the potential benefits? If in doubt, should physicians err on the side of caution or on the side of hope? These questions are at the core of all medical decision making. It is a complicated process because medical knowledge is typically incomplete and ambiguous. It is especially complex to make decisions about whether to use drugs that may prevent disease in the future, particularly when these drugs are given to otherwise healthy individuals. Vaccines are examples of such drugs, and the human papillomavirus (HPV) vaccine is a case in point. zur Hausen, winner of the Nobel Prize in Physiology or Medicine in 2008, discovered that oncogenic HPV causes cervical cancer. 1-4 His discovery led to characterization of the natural history of HPV infection, an understanding of mechanisms of HPV-induced carcinogenesis, and eventuallytothedevelopmentofprophylacticvaccinesagainstHPV infection.
WE‐C‐ValA‐09: A Biological Lung Phantom for IGRT Studies

Purpose: We are evaluating the feasibility of a dynamic biological lung phantom for IGRT studies, with the initial goal of developing a reliable phantom suitable for use in validation of deformable registration and volume rendering studies of the lung. The properties of an ideal lung phantom would include complex geometry, anisotropic inflation, and composition, lobar structure and internal airway architecture similar to that of human lung.Method and Materials: Preserved swine lung was obtained and compared to human lung. The prepared lung was statically inflated to different volumes using a regulated nitrogen supply, and can also be dynamically inflated using a medical ventilator. The inflated phantom was imaged on a GE Lightspeed CT scanner. Volume rendering of the CTimage data was performed to visualize and determine coordinates of airway bifurcations.Results: Preserved swine lung was determined to be comparable to human lung in terms of tissue radiological and physical properties, lobar structure, airway architecture, volume and mass. Rendered airway vs. physiologic airway dimensions are undergoing verification by dissection. Analysis of CTimages and volume rendering data demonstrates that the airway architecture may be followed to at least the 5th airway bifurcation, yielding a conservative minimum of 31 reproducible anatomic landmarks evenly distributed throughout the lung. By visual inspection, it is possible to follow the displacement vector of these landmarks in sequential images.Conclusion: Initial analysis shows that a swine lung phantom meets a number of the requirements of a reliable and functional phantom for validation of deformable registration and volume rendering methods. Reference points generated using the CT/volume rendering technique may be useful as a validation tool for both feature‐ and intensity‐based deformable registration techniques. Ongoing study will evaluate the potential of the lung phantom for use in planning, delivering, and validating 4D IGRT.
Gene Expression Variability in Human Hepatic Drug Metabolizing Enzymes and Transporters

Interindividual variability in the expression of drug-metabolizing enzymes and transporters (DMETs) in human liver may contribute to interindividual differences in drug efficacy and adverse reactions. Published studies that analyzed variability in the expression of DMET genes were limited by sample sizes and the number of genes profiled. We systematically analyzed the expression of 374 DMETs from a microarray data set consisting of gene expression profiles derived from 427 human liver samples. The standard deviation of interindividual expression for DMET genes was much higher than that for non-DMET genes. The 20 DMET genes with the largest variability in the expression provided examples of the interindividual variation. Gene expression data were also analyzed using network analysis methods, which delineates the similarities of biological functionalities and regulation mechanisms for these highly variable DMET genes. Expression variability of human hepatic DMET genes may affect drug-gene interactions and disease susceptibility, with concomitant clinical implications.
Leukocyte migration from a fish eye's view

In the last five years, the zebrafish (Danio rerio) has rapidly gained popularity as a model system for studying leukocyte migration and trafficking in vivo. The optical clarity of zebrafish embryos, as well as the potential for genetic manipulation and the development of tools for live imaging, have provided new insight into how leukocytes migrate in response to directional cues in live animals. This Commentary discusses recent progress in our understanding of how leukocytes migrate in vivo, including the role of intracellular signaling through phosphatidylinositol 3-kinase (PI3K) in both random and directed migration. The importance of leukocyte reverse migration in the resolution of inflammation will also be discussed. Finally, we will highlight how zebrafish models have helped to provide new insight into leukocyte migration and the way in which migration is altered in disease.