cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of magnesium sulfate on bronchoconstriction in the lung periphery

Magnesium sulfate has been shown to be effective clinically as a bronchodilator, but its mechanism of action is unknown. We used a wedged bronchoscope technique to study the ability of MgSO4 at clinically relevant concentrations to attenuate hypocapnia-, acetylcholine- (ACh), and dry air-induced bronchoconstriction in the canine lung periphery. Control experiments demonstrated that consecutive challenges of either hypocapnia or ACh resulted in greater collateral system resistance (Rcs) after the second challenge compared with the first. Intravenous infusion of MgSO4 diminished the maximum response to a second hypocapnic challenge (Rcs = 1.59 +/- 0.29 cmH2O.ml-1.s prechallenge vs. 1.12 +/- 0.20 postchallenge) but had no effect on either ACh- or dry air-induced bronchoconstriction. Serum magnesium levels before MgSO4 administration were 1.59 +/- 0.04 meq/l and rose to 6.20 +/- 0.13 during the infusion. Previous studies demonstrated that nifedipine, like MgSO4 in this study, attenuates hypocapnia-induced bronchoconstriction in the canine lung periphery but has no effect on ACh- or dry air-induced bronchoconstriction. We conclude that these results are consistent with the idea that, like nifedipine, magnesium acts in the airway as a voltage-sensitive calcium channel blocker.
Elastic Fields due to Eigenstrains in a Half-Space

Engineering components inevitably encounter various eigenstrains, such as thermal expansion strains, residual strains, and plastic strains. In this paper, a set of formulas for the analytical solutions to cases of uniform eigenstrains in a cuboidal region-influence coefficients, is presented in terms of derivatives of four key integrals. The linear elastic field caused by arbitrarily distributed eigenstrains in a half-space is thus evaluated by the discrete correlation and fast Fourier transform algorithm, along with the discrete convolution and fast Fourier transform algorithm. By taking advantage of both the convolution and correlation characteristics of the problem, the formulas of influence coefficients and the numerical algorithms are expected to enable efficient and accurate numerical analyses for problems having nonuniform distribution of eigenstrains and for contact problems.
Spontaneous Transient Outward Currents Arise from Microdomains Where BK Channels Are Exposed to a Mean Ca2+ Concentration on the Order of 10 μM during a Ca2+ Spark

Ca(2+) sparks are small, localized cytosolic Ca(2+) transients due to Ca(2+) release from sarcoplasmic reticulum through ryanodine receptors. In smooth muscle, Ca(2+) sparks activate large conductance Ca(2+)-activated K(+) channels (BK channels) in the spark microdomain, thus generating spontaneous transient outward currents (STOCs). The purpose of the present study is to determine experimentally the level of Ca(2+) to which the BK channels are exposed during a spark. Using tight seal, whole-cell recording, we have analyzed the voltage-dependence of the STOC conductance (g((STOC))), and compared it to the voltage-dependence of BK channel activation in excised patches in the presence of different [Ca(2+)]s. The Ca(2+) sparks did not change in amplitude over the range of potentials of interest. In contrast, the magnitude of g((STOC)) remained roughly constant from 20 to -40 mV and then declined steeply at more negative potentials. From this and the voltage dependence of BK channel activation, we conclude that the BK channels underlying STOCs are exposed to a mean [Ca(2+)] on the order of 10 microM during a Ca(2+) spark. The membrane area over which a concentration > or =10 microM is reached has an estimated radius of 150-300 nm, corresponding to an area which is a fraction of one square micron. Moreover, given the constraints imposed by the estimated channel density and the Ca(2+) current during a spark, the BK channels do not appear to be uniformly distributed over the membrane but instead are found at higher density at the spark site.
Evolutionary Strategies of Viruses, Bacteria and Archaea in Hydrothermal Vent Ecosystems Revealed through Metagenomics

The deep-sea hydrothermal vent habitat hosts a diverse community of archaea and bacteria that withstand extreme fluctuations in environmental conditions. Abundant viruses in these systems, a high proportion of which are lysogenic, must also withstand these environmental extremes. Here, we explore the evolutionary strategies of both microorganisms and viruses in hydrothermal systems through comparative analysis of a cellular and viral metagenome, collected by size fractionation of high temperature fluids from a diffuse flow hydrothermal vent. We detected a high enrichment of mobile elements and proviruses in the cellular fraction relative to microorganisms in other environments. We observed a relatively high abundance of genes related to energy metabolism as well as cofactors and vitamins in the viral fraction compared to the cellular fraction, which suggest encoding of auxiliary metabolic genes on viral genomes. Moreover, the observation of stronger purifying selection in the viral versus cellular gene pool suggests viral strategies that promote prolonged host integration. Our results demonstrate that there is great potential for hydrothermal vent viruses to integrate into hosts, facilitate horizontal gene transfer, and express or transfer genes that manipulate the hosts’ functional capabilities.
The Stability of Social Groups in Childhood and Adolescence: The Role of the Classroom Social Environment.

This study provides a developmental analysis of childhood and adolescent social relationships within the school context. The social groups of 220 fourth graders and 475 seventh graders were tracked over a one year interval. The initial results indicated that approximately 30% of the social groups were identified as stable in that they maintained at least 50% of their membership over the one year interval. However, the stability in group affiliations was a function of the stability of the composition of the classroom. When schools did not promote classrooms as a unit, only 6.8% of social groups were stable, as compared to 55% of groups being stable when the school did promote classrooms as a unit. This school effect in group stability was demonstrated by a high correlation (rs = .97) between classroom stability and group stability. Even in unstable classrooms, individuals were more likely to maintain affiliations when group members were assigned to the same classroom. This work suggests that stable environments promote stable relationships, which in turn, may promote greater continuity in the organization of behavioral patterns.
Investigation of creep threshold stresses using in situ TEM straining experiment in an Al–5Y2O3–10SiC composite

Abstract Creep behavior of metal matrix composites is similar to dispersion strengthen alloys and characterized by the presence of a threshold stress below which the creep rate is negligible. This threshold stress is attributed, at least in dispersion-strengthened alloys, to dislocation particle interactions in which the detachment of the dislocations from the particle is the rate-limiting step. Creep experiments were performed on an Al–5Y 2 O 3 –10SiC composite in the temperature range of 473 and 573 K and the nature of the dislocation–particle interaction was determined by performing in situ straining experiments at elevated temperature in a transmission electron microscope. The threshold stress and the detachment stress are temperature dependent and the detachment stress is less than the threshold stress emphasizing the contribution of load transfer from the matrix to the reinforcement phase.
COSY INFINITY Version 9

Abstract In this paper, we review the features in the newly released version of COSY INFINITY, which currently has a base of more than 1000 registered users, focusing on the topics which are new and some topics which became available after the first release of the previous versions 8 and 8.1. The recent main enhancements of the code are devoted to reliability and efficiency of the computation, to verified integration, and to rigorous global optimization. There are various data types available in COSY INFINITY to support these goals, and the paper also reviews the feature and usage of those data types.
Ultrastructural effects of lethal freezing on brain, muscle and Malpighian tubules from freeze-tolerant larvae of the gall fly, Eurosta solidaginis

Abstract In preparation for winter low temperatures, larvae of the gall fly, Eurosta solidaginis, accumulate the cryoprotectants glycerol, sorbitol, and trehalose. The fat body cells of these freeze-tolerant larvae can survive intracellular freezing to −80°C for 48 h even though no whole larvae survive this treatment. We hypothesized that some other tissue was more susceptible to freezing and therefore may be responsible for larval death. This paper compares the ultrastructure of brain, muscle, and Malpighian tubules between non-lethally frozen and lethally frozen freeze-tolerant larvae. The nuclei of cortical brain cells from lethally frozen larvae exhibited clumped chromatin and nuclear membranes with occasional expansions or `blebs' of the intermembranous space, while the cytoplasm contained swollen spheres of endoplasmic reticulum. In contrast, non-lethally frozen brain contained nuclei with evenly dispersed chromatin, smooth nuclear membranes and a cytoplasm free of swollen endoplasmic reticulum. Muscle tissue of lethally frozen larvae contained disrupted myofilaments surrounding the Z-line in comparison to non-lethally frozen muscle which had myofilaments extending all the way to the Z-line. Alterations of Malpighian tubule cells from lethally frozen larvae included an extracted cytoplasm with swollen and rounded mitochondria. In contrast, Malpighian tubule cells from non-lethally frozen larvae had a more concentrated cytoplasm with many rod-shaped mitochondria. Results show alterations to all three tissue types due to lethal freezing. The brain tissue contained the most observable alterations and therefore may be the most susceptible to lethal freeze damage.
CP violation in radiative b decays

Abstract According to the standard CKM model, the rare decays of the B-mesons can produce CP -violating asymmetries that may be accessible to experiment. I investigate the radiative decays b → sγ and b → dγ , at the quark level, and I find asymmetries of the order (0.1–1)% and (1–10)%, respectively. I use a modified formalism to calculate the as the relevant contributions, and simplifies handling the important QCD corrections to the amplitudes.
Pain, Delirium, and Physical Function in Skilled Nursing Home Patients With Dementia

Abstract Objective Skilled nursing facilities (SNFs) are major sites of postacute care for patients with dementia. A recent Office of the Inspector General report indicated that outcomes in SNFs are suboptimal because of poor-quality treatment, including the failure to provide needed care. Pain is frequently unrecognized and untreated in patients with dementia. The aim of this exploratory study was to examine the effect daily pain has on delirium and physical function in patients with dementia in SNFs. The association of daily pain with discharge disposition was also examined. Design Secondary analysis of data from an on-going randomized clinical trial. Setting Eight SNFs located in central and northeast Pennsylvania. Participants A total of 103 SNF patients with adjudicated dementia and delirium diagnoses and a mean age of 86 (±6.8) years; most were women (66%) and white (98%). Measurements Measures of pain (Pain Assessment in Advanced Dementia), delirium (Confusion Assessment Method), and physical function (Barthel Index) were taken daily for 30 days or until discharge. Results On days when participants experienced greater than their average level of pain, they also experienced more delirium symptoms ( P P P = .003) or be placed in a nursing home (OR 4.77, 95% CI 1.7–13.2, P = .003) compared with returning to the community at 3-month follow-up. Conclusion Greater attention to pain in patients with dementia may be a potential solution to some of the quality problems and high costs of care in SNFs.
Activation of transducin by a Xenopus short wavelength visual pigment.

Phototransduction in cones differs significantly from that in rods in sensitivity, kinetics, and recovery following exposure to light. The contribution that the visual pigment makes in determining the cone response was investigated biochemically by expressing a Xenopus violet cone opsin (VCOP) cDNA in COS1 cells and assaying the light-dependent activation of transducin. Light-exposed VCOP stimulated [35S]guanosine 5′-(γ-thio)triphosphate nucleotide exchange on bovine rod transducin in a time-dependent manner with a half-time for activation of 0.75 min, similar to that of bovine rhodopsin. In exhaustive binding assays, VCOP and rhodopsin activity showed similar concentration dependence with half-maximal activation occurring at 0.02 mol of pigment/mol of transducin. Although VCOP was able to activate as many as 12 transducins per photoisomerization, rhodopsin catalyzed significantly more. When assays were performed with λ > 420 nm illumination, VCOP exhibited rapid regeneration and high affinity for the photoregenerated 11-cis-retinal. Recycling of the chromophore and reactivation of the pigment resulted in multiple activations of transducin, whereas a maximum of 1 transducin per VCOP was activated under brief illumination. The decay of the active species formed following photobleaching was complete in
Exploiting Rotational Symmetry for the Design of Ultra-Wideband Planar Phased Array Layouts

Two new phased array design techniques are introduced that utilize rotational symmetry to avoid grating lobes during scanning and over ultra-wide bandwidths. The first is an optimization method, which employs the covariance matrix adaptation evolutionary strategy to determine the best locations of elements inside a sector of a circle. The second technique uses standard periodic lattices inside the same circular sector. Although the segments themselves are internally periodic, the rotational symmetry of the full array eliminates the occurrence of grating lobes and is capable of generating antenna element layouts with useful ultra-wideband properties. These design techniques yield arrays with not only ultra-wideband characteristics, but properties that lend themselves to relatively straightforward modular construction, especially the semi-periodic variety.
Resonance effects in thin film proton backscattering spectrometry

The use of protons in backscattering analysis can be of advantage when detecting low-Z elements in a matrix of high-Z material, due to enhancement of the cross section by nuclear potential scattering. For light elements resonances in the nuclear scattering cross section become important in thin film analysis. The spectrum of backscattered protons shows a peak whose width may not only depend on the film thickness but also on the resonance. Effects of film thickness on the analysis of thin films in the region of the 0.46 MeV and the 1.73 MeV resonance in the elastic backscatter spectrum of protons from carbon are discussed. Values for the elastic scattering cross section for protons on carbon in the range from 0.445 MeV to 2.0 MeV at a laboratory angle of 160° are given.
Linkage relationships of the Z-linked silver, slow feathering, and pop-eye loci

Abstract A three-point genetic linkage test was conducted to establish linear relationships of the Z-linked loci pop-eye (POP*), silver (S*), and rate of feathering (K*). Linkage values obtained in a back cross were POP* - 17.8 - S* - 2.4 - K* (n = 169). The POP* - K* distance was 19.0, supporting this linear order. The data support the previous assignment of POP* to the short arm of the Z chromosome. Based on previous reports, of the three loci studied, POP* is closest to the centromere.
NR4A Orphan Nuclear Receptors in Cardiovascular Biology

The NR4A orphan nuclear receptor subfamily is comprised of the highly homologous receptors Nur77 (NR4A1), Nurr1 (NR4A2), and NOR1 (NR4A3). These evolutionarily conserved and ancient receptors function as ligand-independent transcription factors that regulate the expression of overlapping target genes. As early response genes, the basal expression level of these receptors is low but rapidly induced as a result of changes in environmental cues. The transcriptional activity of these receptors is primarily regulated by gene induction and posttranslational modifications of the receptor including phosphorylation. NR4A receptors were initially identified in the brain and early functional studies suggested a role for these receptors in signal- and cell-specific stimulation of both apoptosis and proliferation. More recent studies have revealed much broader functions of these orphan receptors including the regulation of genes involved in cancer, metabolism, energy balance, atherosclerosis, and vascular remodeling. In this review, we will discuss our current understanding of the molecular biology of NR4A receptors and summarize recent studies suggesting an important role of these orphan receptors in vascular biology.
A conformational change in the methyltransferase from Clostridium thermoaceticum facilitates the methyl transfer from (6S)-methyltetrahydrofolate to the corrinoid/iron-sulfur protein in the acetyl-CoA pathway

The methyltetrahydrofolate:corrinoid/iron−sulfur protein methyltransferase (MeTr) from Clostridium thermoaceticum catalyzes the methylation of a corrinoid/iron−sulfur protein (C/Fe-SP) by the N5 methyl group of (6S)-methyltetrahydrofolate (CH3-H4folate). This is an important reaction in the reductive acetyl-CoA pathway. The forward and reverse reactions of MeTr have a pH dependence that appears to reflect protonation of a group on the protein [Zhao, S., Roberts, D. L., & Ragsdale, S. W. (1995) Biochemistry 34, 15075−15083]. In the work reported here, fluorescence and rapid reaction kinetics were used to demonstrate that this protonation elicits a rate-limiting conformational change. As the pH was lowered, the emission maximum for intrinsic tryptophan fluorescence underwent a red shift (pKa = 5.4) and the emission intensity increased (pKa = 5.1). The extrinsic fluorescence probe, 4,4‘-bis-1-phenylamino-8-napthalenesulfonate (bis-ANS) was used to report on the conformational change. The bis-ANS fluorescence...
Studies in steroid metabolism. XI. Gas chromatographic determination of estrogens in human pregnancy urine.

Abstract A rapid, chemically specific, and reproducible method for the determination of estrogens in pregnancy urine by means of gas-liquid partition chromatography is described. The use of estrogen acetates to facilitate separation on short silicone grease columns has been further established. Further evidence for the slight destruction of urinary estrogen conjugates by mineral acid is demonstrated.
Oligomeric interface modifiers in hybrid polymer solar cell prototypes investigated by fluorescence voltage spectroscopy

Carboxylated oligothiophenes were evaluated as interfacial modifiers between the organic poly(3-hexylthiophene) (P3HT) and inorganic TiO2 layers in bilayer hybrid polymer solar cells. Carboxylated oligothiophenes can be isolated using conventional purification techniques resulting in pure, monodisperse molecules with 100% carboxylation. Device prototypes using carboxylated oligothiophenes as interfacial modifiers showed improved performance in the open-circuit voltage and fill factor over devices using unmodified oligothiophenes as interfacial modifiers. X-ray photoelectron spectroscopy (XPS) studies supported the idea that interface layer adhesion was improved by functionalizing oligothiophenes with a carboxyl moiety. Wide-field fluorescence images revealed that devices made using carboxylated oligothiophenes had fewer aggregates in the P3HT layers atop the modified TiO2 surface. Hysteresis seen in the fluorescence intensity as a function of applied bias, obtained from In-Device Fluorescence Voltage Spectroscopy (ID-FVS), was found to be a diagnostic criterion of the quality of the hybrid interface modification. The best interfaces were found using oligothiophenes functionalized with carboxylates, which created smooth layers on TiO2, and showed no hysteresis, suggesting elimination of interfacial charge traps. However, this hysteresis could be re-introduced by increasing the scan rate of the applied bias, suggesting that smooth P3HT layers created by carboxylated oligothiophene interface modifiers were necessary but not sufficient for sustaining improved photovoltaic properties especially during long-term device operation.
Ambient fine particulate concentrations and chemical composition at two sampling sites in metropolitan Pittsburgh: a 2001 intensive summer study

The concentration and chemical composition of ambient fine particulate material (PM2.5) is reported for two sampling sites in the Pittsburgh, Pennsylvania metropolitan area: the Department of Energy, National Energy Technology Laboratory (NETL) PM study site south of the city center, and the Carnegie Mellon Pittsburgh Air Quality Study (PAQS) site 5 km east of central Pittsburgh established with funding by the EPA Supersites Program and by DOE-NETL. Data from these sampling sites were characterized by one to three-day episodes with PM2.5 concentrations (constructed from the sum of the chemical components) exceeding 40.0 mug m(-3). The episodes were dominated by high concentrations of ammonium sulfate. The fine particle concentrations were compared with meteorological data from surface weather maps and a Hybrid Single Particle Lagrangian Integrated Trajectory model (HYSPLIT model), with back-trajectories estimated over 24 h. High PM2.5 concentrations were associated with transition from a high pressure to a low pressure regime in advance of an approaching frontal system indicating long-range transport of pollutants. In contrast, fine particulate organic material appeared to be dominated by nearby sources. Distinct differences were observed in the diurnal variations in concentration between the two sites. The NETL site showed clear maximum concentrations of semi-volatile organic material (SVOM) during midday, and minimum concentrations of nonvolatile organic compounds in the afternoon. In contrast, the Carnegie Mellon PAQS site showed an absence of diurnal variation in SVOM, but still with minimum concentrations of nonvolatile organic compounds in the afternoon and evening. Neither site showed significant diurnal variation in ammonium sulfate. (C) 2004 Elsevier Ltd. All rights reserved.
Induced renal artery stenosis in rabbits: magnetic resonance imaging, angiography, and radionuclide determination of blood volume and blood flow.

Abstract To investigate the ability of MRI to detect alterations due to renal ischemia, a rabbit renal artery stenosis (RAS) model was developed. Seven rabbits had RAS induced by surgically encircling the artery with a polyethylene band which had a lumen of 1 mm, 1 to 2 weeks prior to imaging. The stenosis was confirmed by angiography, and the rabbits were then imaged in a 1.4 T research MRI unit. T 1 was calculated using four inversion recovery sequences with different inversion times. Renal blood flow, using 113 Sn-microspheres, and regional water content by drying were then measured. The average T 1 of the inner medulla was shorter for the ischemic (1574 msec) than for the contralateral kidney (1849 msec), while no change was noted in the cortex. Ischemic kidneys had less distinct outer medullary zones on IR images with TI = 600 msec than did contralateral or control kidneys. Blood flow to both the cortex and medulla were markedly reduced in ischemic kidneys compared with contralateral kidneys (119.5 vs. 391 ml/min/100 gm for cortex and 19.8 vs. 50.8 ml/min/100 gm for medulla). Renal water and blood content were less affected. Our rabbit model of renal artery stenosis with MRI, radionuclide, and angiographic correlation has the potential to increase our understanding of MR imaging of the rabbit kidney.
Air medical transport of the injured patient: scene versus referring hospital.

Abstract Introduction: In a rural service area, does the outcome of air medical patients transferred from the scene of injury differ from that of patients transferred from a primary receiving hospital? Methods: Retrospective review of all injured patients transported by air to a single trauma center during calendar year 1996. Data collected include basic patient demographics, time of injury, revised trauma score (RTS), injury severity score (ISS), probability of survival (PS), hospital length of stay (LOS), complications, disposition, and mortality. Results: Concerning trauma admissions, 594 of 1461 (40.7%) were transported by air: 363 from the scene (24.9%) and 231 from referring hospitals (15.8%). These two groups were similar in demographics, injury severity, hospital LOS, and crude mortality: RTS, 6.61 versus 6.68 ( P > 0.05); ISS, 16.0 versus 16.0 ( P > 0.05); LOS=6.9 days versus 7.3 days ( P > 0.05); mortality=11.8% versus 10.8% ( P > 0.05). The groups differed significantly, however, in time from injury to definitive care (34.2 minutes versus 196.2 minutes, P P = 0.009), and potentially preventable deaths (PS > 0.5, 11.6% versus 44%, P = 0.02). Conclusion: Patient groups were similar, suggesting similar triage criteria. Patients transferred from a referring hospital took almost six times longer to reach definitive care and may have suffered an increased morbidity and mortality on this basis.
Bacterial Vaginosis: Are We Coming Full Circle?

Bhattacharyya, a consulting venereologist from Sheffield, England. During the dis cussion on the epidemiology of BV, Dr Josey stated the following: "In my opinion, H v. vaginitis is a form of venereal disease. If we can identify an organism as being associated primarily with the genital sys tem, I would automatically classify it as causing a venereal infection" [ 1 ]. Indeed, that was the teaching in textbooks of that era.
Solving Navier-Stokes Equations with Advanced Turbulence Models on Three-Dimensional Unstructured Grids

USM3D is a widely-used unstructured flow solver for simulating inviscid and viscous flows over complex geometries. The current version (version 5.0) of USM3D, however, does not have advanced turbulence models to accurately simulate complicated flows. We have implemented two modified versions of the original Jones and Launder k-epsilon two-equation turbulence model and the Girimaji algebraic Reynolds stress model in USM3D. Tests have been conducted for two flat plate boundary layer cases, a RAE2822 airfoil and an ONERA M6 wing. The results are compared with those of empirical formulae, theoretical results and the existing Spalart-Allmaras one-equation model.
Variability in spine loading model performance.

Abstract Objective. To assess the sources of variability associated with an EMG-assisted model of spine loading. Design. In vivo measurements of trunk dynamics, lifting moments and muscle activities were used as inputs into an EMG-assisted spine loading model. Background. Several types of variability are inherent in biomechanical assessments of risk associated with trunk bending motions during lifting. Variability may occur as a function of variations in spine loading due to either subject variations in motion profiles (kinematics) or biomechanical model performance. Methods. Twelve experienced and inexperienced materials handlers performed 10 repeated lifts where load weight, asymmetry, and velocity were varied. The experiment was replicated on a second day to assess day to day variability. Results. These model performance variables indicated that variability was mainly a function of subject characteristics and experience. Minor variations in variability were associated with the task asymmetry and weight lifted. Advanced analyses suggested that experienced workers had a greater range of back motion compared to inexperienced workers which would affect the length–strength component of the model calibration. Conclusions. This study indicates that for the results of an EMG-assisted model to be accurate, it is important to ensure that the model reflects a realistic relationship between the trunk muscle length and the muscle force production capacity. Underestimation if this relationship can degrade model fidelity and robustness. Relevance These results imply that by properly calibrating the model it is then reasonable to assume that the vast majority of variations observed in repeated exertions of a particular trial are due to kinematic and kinetic differences inherent in the muscle control system and not a function of model randomness.
Evidence suggests slab melting in arc magmas

Most recent geology textbooks state that subduction-related volcanism is due to the melting of the down-going lithosphere. However, for the last 30 years, few in the field have seriously believed that the subducting slab is the source of arc basalts. The accepted hypothesis involves melting of the mantle wedge above the slab via hydrous fluids produced during the transition of the subducting basalt from amphibolite to eclogite. The parental basalts differentiate primarily through crystal fractionation, magma mixing, and differentiation at the Mohorovicic discontinuity into andesites and dacites as they ascend; the basalts are too dense to rise through the lower continental crust. This explains the relative abundance of differentiated rocks in arcs.
Progesterone Action: Regulation of Avidin Biosynthesis by Hen Oviduct in Vivo and in Vitro

The role of progesterone in regulating avidin synthesis in the magnum of the chick oviduct was studied both in vivo and in vitro. In estrogen pretreated animals, after a single injection of progesterone in oil, avidin became measurable at 10 hr and oviduct avidin content reached a maximum by 20 hr. Oviduct ovalbumin and lysozyme content were not affected. Although estrogen alone could not stimulate avidin synthesis, it acted synergistically with progesterone to produce a doubling of the induced level. Incubation of oviduct magnum minces pretreated with estrogen and progesterone resulted in a linear increase of avidin content for 72 hr. Added avidin was stable in vitro, declining only 10%/day. Avidin induction was inhibited by cycloheximide. Actinomycin D inhibited avidin biosynthesis by 50% or more under conditions where total protein synthesis was unaffected. The data suggest that progesterone acts in the hen oviduct to induce the synthesis of new avidin molecules. (Endocrinology 83: 11, 1968)
Microbial invasion: A covert activity?

In contrast to nonpathogenic microorganisms that exist happily in biofilms on various organic and inorganic surfaces, many pathogenic microbes have the additional ability to invade host tissues by ...
Root systems of some Chihuahuan Desert plants

Abstract Root systems of 11 shrub or shrub-like species, 11 grass species, 19 perennial forb species and four annual forb species were excavated on the Jornada Experimental Range in the northern Chihuahuan Desert in southern New Mexico, U.S.A. Maximum radial horizontal spread of shrub root systems usually occurred above calcic and petrocalcic horizons at depths above 1 m. With one exception, all shrub species roots were traced through calcic and petrocalcic horizons to depths down to 5 m. Upward growing roots reaching very shallow depths (
Generalized perfect arrays and Menon difference sets

Given an s 1 × ... × s rinteger-valued array A and a (0, 1) vector z = (z 1, ..., z r), form the array A′ from A by recursively adjoining a negative copy of the current array for each dimension i where z i = 1. A is a generalized perfect array type z if all periodic autocorrelation coefficients of A′ are zero, except for shifts (u 1, ..., u r) where u i, - 0 (mod s i) for all i. The array is perfect if z = (0, ..., 0) and binary if the array elements are all ±1. A nontrivial perfect binary array (PBA) is equivalent to a Menon difference set in an abelian group. Using only elementary techniques, we prove various construction theorems for generalized perfect arrays and establish conditions on their existence. We show that a generalized PBA whose type is not (0, ..., 0) is equivalent to a relative difference set in an abelian factor group. We recursively construct several infinite families of generalized PBAs, and deduce nonexistence results for generalized PBAs whose type is not (0, ..., 0) from well-known nonexistence results for PBAs. A central result is that a PBA with 22y 32u elements and no dimension divisible by 9 exists if and only if no dimension is divisible by 2 y+2. The results presented here include and enlarge the set of sizes of all previously known generalized PBAs.
Family perspective of medical care and grief support after field termination by emergency medical services personnel: a preliminary report.

Objective. To determine the acceptance by family members regarding nontransport of patients in cardiac arrest following unsuccessful resuscitation occurring in private residences. Methods. This was a survey with a structured telephone interview. Inclusion criteria included adult patients in asystolic nontraumatic cardiac arrest. The setting was an urban multitiered emergency medical services (EMS) system. Termination of field resuscitation efforts was authorized by an emergency medicine physician at a medical control base station after set protocol criteria. Support services were provided by trained personnel. Results. Thirty-three follow-up interviews were completed with a family member. Thirty-two (97%) of the contacted family members expressed satisfaction with the services provided by EMS personnel. Twenty-one (64%) patients were not transported to the hospital. All 21 family members of the nontransported were satisfied with both the medical care and the emotional support provided by EMS. Additionally...
DIABETOGENIC EFFECT OFSTILBESTROL IN FORCE-FED NORMAL AND PARTIALLY DEPANCREATIZED RATS

THIS REPORT EXTENDS PRELIMINARY OBSERVATIONS (1, 2) that under certain experimental conditions the administration of stilbestrol to rats causes hyperglycemia HIS REPORT andglycosuria. This substance administered to partially depancrea-tized, non-glycosuric rats on aconstant medium carbohydrate diet produced amarked glycosuria in all of a large series of cases. Other estrogens were found to have this property and massive doses of androgens were weakly effective. In normal non-glycosuric rats on a constant high carbohydrate diet stilbestrol produced a mild, temporary glycosuria in the majority of a large series of cases. Dolin, Josephand Gaunt (3) have reported thatestrogens are effective in intensifying theglycosuriaof the partially depancreatised ferret. Male rats of the Sprague-Dawley strain were used. Normal and partially depancreatized animals were studied. Partial pancreatectomy was carried out at a body weight of 45 to 80 gm. In one series ofanimals all of the pancreas was removed except that portion...
Preparation for Percutaneous Ablation Procedures

Percutaneous tumor ablation is now commonly used to treat a wide range of focal tumors. Patients eligible for ablation often have complex medical problems that preclude them from receiving other treatments. The interventional radiologist needs to perform a careful clinical evaluation of each patient before the procedure to determine which patients are suitable candidates for treatment and to identify patients who may be at a higher risk for complications. The clinical consultation also provides an opportunity to prepare the patient for the ablation and to appropriately plan the procedure. In this article, we discuss key components of the consultation and concepts regarding patient evaluation and preparation for a tumor ablation procedure.
The fictional transfiguration of Jesus: Images of Jesus in literature

Over the years the literary world has been one of the most productive and creative sources of Jesus interpretation. This article gives an overview of som aspects of developments in this filed with reference to the African and Afriko.net contexts. The way in which Jesus is fictionally transformed may reflect the influence of scholarly research, popular and innovative Jesus interpretations, existential questions, and cultural fluctuations, or simply a celebration of imagination. The relationship between theology and literature is vital to both fields. Theology is challenged by the freedom of the novel and the novel stimulated by theological findings. After dealing with some categories of fictional narratives, a Jew examples are discussed. The article gives attention to Jesus in post-modem novels and in postcolonial literature. An African novel is referred to and then Jesus is dealt with more extensively in Afrikaans poems. Examples are given from the work of SheilaCussons, Breyten Breytenbach and Adam Small. The article closes with the sentiment that Jesus interpretations remain a critical and creative comment on humankind and its religion.
The role of synaptic inhibitory mechanisms in neuropsychological systems

Abstract Possible synaptic mechanisms that could produce “inhibition” of the output of a limited neural system, such as the response of a given pool of neurons, are considered. A particular example of inhibition, the reduction in amplitude of the gross evoked cortical polysensory association response that occurs during behavioral attention, is analyzed. It appears that when the animal (cat) attends to a novel stimulus, the ongoing level of activity of individual neurons in association cortex increases markedly. The concominant reduction in amplitude of the gross response evoked by a repeated peripheral probe stimulus (click, light flash, or forepaw shock) appears to be proportional to the degree of increase in ongoing unit activity. Electrical activation of frontal cortex in the anesthetized preparation is shown to replicate effects of attention in the waking animal on gross and unit activity in association cortex.
Spectroscopic analysis of chlorophyll model complexes: methyl ester ClFe(III)pheophorbides.

As models for chlorophyll a (Chl a), methyl ester ClFe(III)pheophorbides (1, pheophorbide a; 2, mesopheophorbide a; and 3, mesopyropheophorbide a) were examined by Fourier transform infrared (FTIR) absorption and resonance Raman (RR) spectroscopy. The infrared (IR) chlorin band above 1600 cm−1, assigned as a Ca-Cm mode (Andersson et al. (1987) J. Am. Chem. Soc. 109, 2908–2916) is shown to be metal-sensitive and responsive to spin state and coordination number for dihydroporphyrins, as well as being diagnostic for the chlorin vs. porphyrin or bacteriochlorin macrocycle. Frequency variations for this metallochlorin IR band thus parallel those of the v10 RR mode of porphyrins in their predictive utility. Qy excitation SERRS spectra of Chl a were compared with Qy excitation RR spectra of 1 and methyl Ni(II)pyropheophorbide a. The data demonstrate that 5-coordinate ClFe(III)pheophorbides are better models for chlorophylls than are ruffled 4-coordinate Ni(II)pheophorbides. Major spectral differences between the three chlorophyll models are associated with the C-9 keto and/or C-10 carbomethoxy vibrational modes. The approx. 1700 cm−1 IR band was formerly assigned solely to v(C = O) of the C-9 keto group. However, this IR feature shifts down to approx. 1685 cm−1 and nearly doubles in intensity when the C-10 carbomethoxy is removed, as for 3. Similar frequency downshifts coupled with intensity increases in the IR are found in the literature on chlorophylls. RR spectra of pheophorbides having the C-10 carbomethoxy group (1 and 2) have bands at both approx. 1700 and approx. 1735 cm−1. However, the C-9 keto v(C = O) mode of pyrophorbins also downshifts to approx. 1685 cm−1, as in the IR spectra. The approx. 1735 cm−1 ester RR mode disappears in the case of pyrophorbins, and is never RR active for nonconjugated esters of porphyrins or chlorins. These data demonstrate an interaction between the C-10 and C-9 carbonyls of phorbins. They also indicate that phorbins tend conjugation of the C-10 ester. Biological examples of such conjugation effects have recently been reported, e.g., for the Chl a π-cation radical (Heald et al. (1988) J. Phys. Chem. 92, 4820–4824). Because the phorbin E ring is the major structural feature distinguishing chlorophylls from non-photo-synthetic systems, the participation of the C-10 ester in ring conjugation is suggestive of its biological importance.
DIVORCE VERSUS INTACT PARENTAL MARRIAGE AND PERCEIVED RISK AND DYADIC TRUST IN PRESENT HETEROSEXUAL RELATIONSHIPS

The relationship between parental divorce and intimate relationships in late adolescence was estimated for 60 undergraduates (17 men, 43 women). Subjects from divorced families were assessed to address whether they perceived their present heterosexual relationship to be risky and if they were less trusting of their partners than were subjects from intact families. Divorce appears to be transmitted through generations in a family. Dyadic Trust and Perceived Risk were investigated as two learned components passed down within families, thereby contributing to a cycle of divorce. A correlation was found between parents' marital status and children's trust in their dating partners. An inverse relationship was indicated; when ratings of trust are low, ratings of perceived risk are high. A possible order of this relationship was discussed, i.e., low dyadic trust preceded perceived risk. One implication of these findings was that children of divorced parents may benefit from being shown how failures in relationships may result from negative expectations.
Physical and Chemical Analyses of Film Formed at Air-Water Interface on Reconstitution of Whole Milk Powders

Abstract When whole milk powder is added to water a major portion of it dissolves but some material remains insoluble and forms a film at the air-water interface making further powder wetting impossible without agitation. Studies were undertaken to determine the physical characteristics and composition of this film. Film balance studies showed the material to be multimolecular in depth, compressible but non-elastic. Small amounts of the interfacial product have been collected and analyzed for total lipid, cholesterol, fatty acids, nitrogen, phosphorous, hexose, hexosamine and neuraminic acid. Gas-liquid chromatography showed that the film contained a relatively high concentration of C 18 saturated fatty acids. Gel electrophoresis showed that the film contained a number of sugar-protein complexes. Increasing the temperature of the water on which the film was spread or heating the powder before solution reduced the film strength. The surface film formed by milk powders containing liquid fat was so weak that the powder had self-dispersing properties.
A facile method of isolation for the iron molybdenum cofactor of nitrogenase and bacterial ferritin from extracts of azotobacter vinelandii

Abstract An alternative method has been developed for the isolation of both the iron molybdenum cofactor of nitrogenase (FeMoco), a small molecular weight FeMoS cluster which is the putative nitrogen- reducing site of the enzyme, and bacterioferritin, an iron storage protein similar to other ferritins, but containing heme prosthetic groups. Previously the isolation of these two species, the characterization of which is of significant current interest, has been dependent on the purification of the nitrogenase enzyme from Azotobacter vinelandii . Out new procedure eliminates the use of the anaerobic column chromatography necessary to obtain pure nitrogenase components, involving instead the heat and RNAase/ DNAase treatment of crude extracts of ruptured cells followed by sedimentation (150000 × g for 18 h) of both the 'nitrogenase complex' and bacterioferritin. The redissolved pellet from this centrifugation yields the pure crystalline bacterioferritin on addition of Mg 2+ . and cooling, the iron content of the protein being higher by this method than in previous reports. Likewise, denaturation by acid/base treatment of this protein mixture yields a precipitate which can be extracted with either N -methylformamide or N,N -dimethylformamide containing dithionite ion to yield solutions of FeMoco, as evidenced by UW 45 reconstitution and EPR spectral criteria. Unfortunately, preparations of FeMoco obtained by this method have a variable, but consistently low, Fe/Mo ratio and additional visible spectral features, indicating that they are significantly less pure than that those generated from purified nitrogenase. The aqueous supernatant from the denaturation also yields bacterioferritin, but with a lower iron content than that from the direct crystallization method.
The consumer logistics system: a focal point for study of the household-consumption process

Consumer logistics provides a fresh perspective for the study of household consumption. As consuming households participate in the distribution of products and services, they engage in consumer logistics — the movement and handling of goods and people that is performed by consumers to facilitate consumption. This article characterizes the consumer logistics system in conceptual fashion to provide a basis for future research into the structure and process of consumer logistics at the household level. It then illustrates the system through a model of the consumer logistics process based on empirical evidence, and finally provides implications of this conceptual development for consumer studies research.
An interpretation of the OH stretching region of the vibrational spectrum of ice I

Abstract The consequences of intermolecular coupling of OH bond stretching motions on the vibrational spectrum of polycrystalline ice are considered in detail. This coupling is found to account for the breadth and most of the major features of the spectrum, but the well-defined peak at 3215 cm −1 in the Raman spectrum of polycrystalline H 2 O is not obtained. Arguments are presented which indicate that this feature arises from interactions of the O H stretching motions with the lattice modes.
Institutional Repositories: Faculty Deposits, Marketing, and the Reform of Scholarly Communication

This study explores faculty deposits in institutional repositories (IR) within selected disciplines and identifies the diverse navigational paths to IR sites from library Web site homepages. The statistical relationship between the development of an IR and the presence of a Web site dedicated to the reform of traditional scholarly communication is also explored. The implications for the development of institutional repositories are highlighted.
Cell segmentation and classification via unsupervised shape ranking

As histology patterns vary depending on different tissue types, it is typically necessary to adapt and optimize segmentation algorithms to these tissue type-specific applications. Here we present an unsupervised method that utilizes cell shape cues to achieve this task-specific optimization by introducing a shape ranking function. The proposed algorithm is part of our Layers™ toolkit for image and data analysis for multiplexed immunohistopathology images. To the best of our knowledge, this is the first time that this type of methodology is proposed for segmentation and ranking in cell tissue samples. Our new cell ranking scheme takes into account both shape and scale information and provides information about the quality of the segmentation. First, we introduce cell-shape descriptor that can effectively discriminate the cell-type's morphology. Secondly, we formulate a hierarchical-segmentation as a dynamic optimization problem, where cells are subdivided if they improve a segmentation quality criteria. Third, we propose a numerically efficient algorithm to solve this dynamic optimization problem. Our approach is generic, since we don't assume any particular cell morphology and can be applied to different segmentation problems. We show results in segmenting and ranking thousands of cells from multiplexing images and we compare our method with well established segmentation techniques, obtaining very encouraging results.