cssi/SciSciGPT-SciSciNet huggingface dataset:
Somatostatin in the idiopathic inflammatory bowel diseases.

To study the effect of mucosal inflammation on tissue concentrations of somatostatin, the distribution and concentration of somatostatin in specimens of normal and abnormal (ulcerative colitis and Crohn's disease) ileum and colon were determined by a specific radioimmunoasay. Each tissue specimen obtained at surgery was separated by microdissection into the mucosa-submucosa and the muscularis externa. Immunoreactive somatostatin was acid-extracted from each layer before measurement. Gel chromatography was used to characterize immunoreactive somatostatin measured by radioimmunoassay; somatostatin-28 was the major immunoreactive species measured in human intestine. In normal colon, concentrations of somatostatin were not related to patient age. Concentrations of immunoreactive somatostatin in the mucosa-submucosa of the descending colon were significantly decreased in ulcerative colitis and in Crohn's colitis, compared with normal colon. There was no apparent relationship between concentrations of somatostatin and the duration of inflammatory bowel disease. However, somatostatin concentrations appeared to be lower in patients with severe colitis than in patients with minimal colitis. The decrease in mucosal-submucosal concentrations of somatostatin is in agreement with previous morphologic studies, which have suggested diminished populations of endocrine cells in ulcerative colitis. The possible role of somatostatin in the colon suggests that further studies of the alteration of this gut peptide may be useful in understanding a component of the pathophysiology of idiopathic inflammatory bowel disease.
Fluorometric High Performance Liquid Chromatography for Quantitation of Naproxen in Serum

Abstract A simple, sensitive and reliable HPLC method for the determination of naproxen in serum is presented. Samples were prepared by a protein precipitation method using acetonitrile. A reversed-phase C-18 column was used with a mobile phase consisting of 47% acetonitrile and 53% pH 2.5 buffer solution. A fluorescence detection with excitation wavelength of 230 nm and emission wavelength of 370 nm provided high sensitivity and specificity with no interference from normal serum constituents. The limit of quantitation was 2.0 ng/ml with a CV of 10.6%. The standard plots were highly linear (r>0.999) over the range of 10.0–200.0 ng/ml. The average recovery was 97% and the CVs of inter- and intra-day variabilities were 2.0% and 1.2%, respectively, for the entire calibration range. The method was used for the measurement of the time course of naproxen in dog serum after administration of a topical gel.
Constriction of native coronary collaterals.

See article by Mansaray et al. [5] (pages 359–366) in this issue. Interconnections between adjacent coronary arteries, known as “collateral vessels,” were discovered as early as the 17th century [1]. Anatomically, collaterals provide conduits through which blood can flow from normal to jeopardized myocardial regions, following obstruction of the antegrade blood supply. However, controversy has existed for decades about the true functional significance of the coronary collateral system. Native collateral vessels, consisting of thin walled vascular structures with a rudimentary smooth muscle coat, were thought for many years to be passive tubes through which blood flowed as a result of a mechanical pressure gradient between the normal and occluded vascular beds. The concept that native collaterals were capable of significant vasomotion, either dilatation or constriction, was not widely accepted. In recent years, however, a number of studies in different animal models have consistently demonstrated that collaterals dilate over the first several minutes following an acute coronary artery occlusion, resulting in a significant increase in blood flow. The mechanism for acute collateral enlargement, however, remains unknown. Collateral dilatation could potentially be mediated … * Tel.: +1-410-955-5997; fax: +1-410-955-0852 lbecker{at}welchlink.welch.jhu.edu
Thin Film Microstructures: Simulation And Theory

The nature of the microstructure of physical vapor-deposited films depends sensitively on the substrate temperature during deposition. At low temperatures the microstructure is porous and ballistic aggregation-like, at intermediate temperatures the microstructure is columnar, and at elevated temperatures the grains are three dimensional. These different microstructural regimes are known as Zone I, II, and III, respectively. A theoretical analysis is presented in which the temporal evolution of the columnar microstructure (Zone II) is studied. The columnar microstructure is shown to be a balance between shadowing (which results in Zone I microstructures) and surface diffusion (which tends to smooth the surface). In addition to predicting the proper microstructure, this analysis properly predicts the temperature at which the Zone II to Zone I microstructural transition occurs. Since bulk diffusion is negligible and surface diffusion controls the microstructure in Zone II, the microstructure in the bulk of the film, may be viewed as frozen and all microstructural evolution occurs at the current, or active, surface. A Monte Carlo computer simulation technique which models the microstructural evolution of the surface is presented. The simulation follows the temporal evolution of realistic three dimensional Zone II microstructures and accounts for growth competition between adjacent grains andmore » the formation of film texture.« less
Sleep in advanced age: a comparison of Mexican American and Anglo American elderly

A sleep questionnaire (SQ) was administered to a sample of 80 Mexican American and 80 Anglo elderly, ages 60 to 96. The two samples were equated on sex, age, and occupational level. Analysis of the 18 SQ scales indicated that twelve showed statistically significant differences between ethnic groups, and six between sexes. The Mexican American sample reported a poorer quality and longer latency of sleep, greater negative affect concerning dreams, longer sleep duration, less dream recall and vividness, more regularity of sleep, and more positive valence towards sleep. Females, more than males, characterized themselves as light sleepers, reported less positive quality and a longer latency of sleep, and endorsed items that reflect security, routine and privacy.
Improving the design of higher-capacity railway tank cars for hazardous materials transport: Optimizing the trade-off between weight and safety

As with many aspects of modern industrial society, decision-makers face trade-offs in considering hazardous materials transportation equipment and practices. Tank cars used for transport of hazardous materials can be made more resistant to damage in accidents through use of a thicker steel tank and other protective features. However, the additional weight of these features reduces the car's capacity and thus its efficiency as a transportation vehicle. In this paper the problem of tank car safety versus weight is developed as a multi-attribute decision problem. North American railroads recently developed specifications for higher capacity tank cars for transportation of hazardous materials including enhanced safety design features. A group of tank car safety design features or "risk reduction options" (RROs) were analyzed with regard to their effect on the conditional probability of release in an accident, and their incremental effect on tank car weight. All possible combinations of these RROs were then analyzed in terms of the reduced release probability per unit of weight increase and the Pareto optimal set of options identified. This set included the combinations of RROs that provided the greatest improvement in safety with the least amount of additional weight for any desired level of tank car weight increase. The analysis was conducted for both non-insulated and insulated tank cars and used two objective functions, minimization of conditional probability of release, and minimization of expected quantity lost, given that a car was derailed in an accident. Sensitivity analyses of the effect of tank car size and use of different objective functions were conducted and the optimality results were found to be robust. The results of this analysis were used by the Association of American Railroads Tank Car Committee to develop new specifications for higher capacity non-insulated and insulated, non-pressure tank cars resulting in an estimated 32% and 24% respective improvement in safety.
Paleomagnetic dating of burial diagenesis in Mississippian carbonates, Utah

[1] The objective of this study is to test models for the origin of widespread secondary magnetizations in the Mississippian Deseret Limestone. The Delle Phosphatic Member of the Deseret Limestone is a source rock for hydrocarbons, and modeling studies indicate that it entered the oil window in the Early Cretaceous during the Sevier orogeny. Paleomagnetic and rock magnetic results from the Deseret Limestone and the stratigraphically equivalent Chainman Shale in central and western Utah indicate that the units contain two ancient magnetizations residing in magnetite. Burial temperatures are too low for the magnetizations to be thermoviscous in origin, and they are interpreted to be chemical remanent magnetizations (CRMs). Fold tests from western Utah indicate the presence of a prefolding Triassic to Jurassic CRM. Geochemical (87Sr/86Sr, δ13C, and δ18O) and petrographic analyses suggest that externally derived fluids did not alter these rocks. This CRM was acquired at the beginning of the oil window and is interpreted to be the result of burial diagenesis of organic matter. A second younger CRM in western central Utah is apparently postfolding and is probably Late Cretaceous to early Tertiary in age. On the basis of the thermal modeling, the timing overlaps with the oil window. These results are consistent with a connection between organic matter maturation and remagnetization. Modeling of the smectite-to-illite transformation in the Deseret Limestone suggests a mean age prior to acquisition of both CRMs, although the range for illitization overlaps with the Triassic to Jurassic CRM. The results of this study support the hypothesis that pervasive CRMs can be related to burial diagenetic processes. In addition, paleomagnetism can be used to determine the timing of such processes, which can benefit hydrocarbon exploration efforts.
Electrical conductance time constants for freely decaying arcs

Electrical conductance time constants for the early stages of free decay after current modulation have been calculated from experimental measurements on a 5 mm diameter cascade arc at atmospheric pressure. The time constants were found by measuring the electric field response of the asymptotic portion of the arc column immediately after a sudden step decrease of arc current. The electric field strength was monitored by means of the copper cooling disks of the cascade, whose probe characteristics were studied thoroughly. The initial high current was supplied by a capacitor discharge circuit which was inductively compensated to produce a square wave pulse of ∼ 2 msec duration. Time constants for initial decay were measured in both argon and nitrogen for initial currents ranging from 100 to 400 amperes. The initial free decay time constants of nitrogen were found to increase weakly from approximately 25 to 35 usec over the initial current range considered. The time constants of argon decreased from approximately 100 to 60 Μsec over the same initial current range.
Studies of the Raman spectra of cyclic and acyclic molecules: Combination and prediction spectrum methods

Abstract A combination of Raman spectroscopy and density functional methods was employed to investigate the spectral features of selected molecules: furfural, 5-hydroxymethyl furfural (HMF), methanol, acetone, acetic acid, and levulinic acid. The computed spectra and measured spectra are in excellent agreement, consistent with previous studies. Using the combination and prediction spectrum method (CPSM), we were able to predict the important spectral features of two platform chemicals, HMF and levulinic acid. The results have shown that CPSM is a useful alternative method for predicting vibrational spectra of complex molecules in the biomass transformation process.
The Relationships Between Selected Physical Characteristics and the Resistance to Shell Failure of Gallus Domesticus Eggs

Abstract EGG shell strength has been measured directly by methods involving techniques of crushing, impact, and puncturing. Kennard (1925), Romanoff (1929), Morgan et al. (1930), Bryant and Sharp (1934), Stewart (1936), Gutowska and Parkhurst (1942), Heuser and Norris (1946), Godfrey (1949), Godfrey and Jaap (1949), Brooks and Hale (1955), and Rauch (1958) all determined egg shell strength by measuring the force necessary to crush the egg. Tully and Franke (1934) and Baskett et al. (1937) measured shell strength employing a puncturing method. Swanson and James (1932), Hale (1954), and Mueller (1957) determined egg shell strength with an impact device. Several attempts have been made to correlate shell strength with other characteristics of eggs and their shells. Stewart (1936) found a significant correlation coefficient of +.509 between shell thickness and breaking strength. Lund et al. (1938), Brooks and Hale (1955), and Rauch (1958 and Rauch (1959) observed similar results. Morgan (1932) and Mueller (1957)…
Submicron diffraction gratings etched on an InP/InGaAsP waveguide edge for wavelength division multiplexing

2D monolithic grating spectrometers for dense wavelength division multiplexing (WDM) show considerable promise to extend the usable bandwidth of optical fibers. Their performance is fundamentally dictated by the grating which is used. First order gratings will theoretically improve the performance of monolithic WDM devices, since WDM devices based on first order gratings do not suffer from an inherent tradeoff between efficiency and broadband operation.
Water hyacinth productivity and detritus accumulation

Water hyacinth [Eichhornia crassipes (Mart) Solms] productivity and detritus accumulation were evaluated in eutrophic lake water with and without added nutrients (fertilized and control reservoirs, respectively). Seasonal changes in plant productivity and detritus accumulation were determined at monthly intervals for one year.
An accurate non-iterative algorithm for computing the length of the position vector to a subsatellite point

The radial distance (length of a position vector) from the geocenter to the geoid as defined by the spherical harmonic potential coefficients is needed e.g. in the process of adjusting satellite altimeter data. The geocentric latitude and longitude associated with this distance are assumed known—in this case derived from satellite altimetry. Typically, the radial distance can be computed to a desired accuracy in an iterative process. Even if a crude initial value is adopted, a sub-meter accuracy is achieved on the second iteration, while the third iteration yields a sub-millimeter accuracy. If the best possible initial value is taken, such as the radial distance to the mean earth ellipsoid, the iterative process may be accelerated by one iteration. But even then two iterations will be needed in most cases. However, an algorithm has been designed that yields excellent results, characterized by a sub-centimeter accuracy, already from the first iteration. It results in important computer savings, considering that in real data reductions of satellite altimetry, the radial distance needs to be computed at thousands of locations.
Effects of methylandrostenediol on weight and cholesterol content of adrenals of cortisone or thiouracil-treated rats.

SummaryCortisone acetate depressed adrenal weight and reduced adrenal cholesterol concentration in male and female rats. Methylandrostenediol (MAD) depleted adrenal cholesterol in both sexes while not influencing adrenal weight. When cortisone acetate and MAD were injected concomitantly, normal adrenal weights were observed in male and female rats. However, adrenal cholesterol content was protected by MAD only in cortisone-treated males. MAD did not prevent adrenal weight loss due to thiouracil, but did deplete cholesterol by 67%.
Quake shakes San Francisco Bay area

A magnitude 5.6 earthquake that shook the San Francisco, Calif. Bay area at 0304:54 UTC on 30 October was the largest temblor in that region since the deadly magnitude 6.9 Loma Prieta earthquake along the San Andreas Fault on 17 October 1989.
Experimental and Numerical Investigation of Vapor Formation in a Fuel Rail

Recently, additional scrutiny is being placed on all vapor releases to the environment from the fuel system of an automobile. In an effort to lower the overall release of fuel vapor, a preliminary study of the vapor formation processes that occur in a low pressure supply fuel rail was undertaken. The first objective of this work was to determine the means by which fuel vapor is generated within the fuel rail, particularly during hot soak conditions. Then, using this information, the next task was to develop a computational fluid dynamics (CFD) code which would model the vapor formation in the rail. An investigation of the fuel rail material and design revealed that the probable mechanism for vapor formation is nucleate boiling from cavities in the fuel rail surface and at the o-ring connections with the fuel injectors. Therefore, an experiment was constructed to investigate the vapor formation from artificial cavities on a metallic surface and at an o-ring interface. The data collected from the experiment included the departure diameter of the vapor bubbles, the bubble frequency, and the bubble rise velocity. These values, which are used to determine the vapor generation rate, were compared to the results predicted by various correlations available in the literature. Subsequently, a CFD model was constructed of the fuel rail, using Star-CD, by incorporating the appropriate vapor generation correlations as user-defined subroutines. The experimental observations clearly demonstrated that a large amount of vapor was generated at the o-ring interface and, to a lesser degree, from the cavities in the metallic surface. A CFD model was constructed to predict the vapor generated in a fuel rail from these cavities. Existing correlations that describe nucleate boiling adequately model this generation mechanism in the fuel rail. This CFD code can be used to determine the amount of vapor formed under various hot soak conditions. An analytical means of predicting the vapor formation at the o-ring interface will have to be developed in order to complete the CFD model.© 2002 ASME
Effects of progesterone administration on infarct volume and functional deficits following permanent focal cerebral ischemia in rats

Recent experimental evidence indicates that progesterone (PROG) protects against various models of brain injury, including ischemic stroke. Most human studies of pharmacologic treatments for acute cerebral stroke have failed despite initial success in animal models. To simulate better the typical human stroke without reperfusion, the present study was conducted to examine the efficacy of PROG on infarct volume and functional outcome in a permanent model of stroke, using direct cauterization of the middle cerebral artery (MCA). Twenty-four male adult Sprague-Dawley rats underwent pMCAO by electro-coagulation and sham operation. After induction of permanent MCA occlusion (pMCAO), the rats received an initial intraperitoneal injection of PROG (8 mg/kg) or vehicle at 1 h post-occlusion followed by subcutaneous injections at 6, 24 and 48 h. Functional deficits were tested on the rotarod and grip-strength meter at 24, 48 and 72 h after pMCAO. The rats were killed 72 h after surgery and isolated brain was sectioned into coronal slices and stained with 2, 3, 5-triphenyltetrazolium chloride (TTC). PROG-treated rats showed a substantial reduction (54.05%) in the volume of the infarct (% contralateral hemisphere) compared to vehicle controls. In addition there was a significant improvement in ability to remain on an accelerating rotarod and increased grip strength observed in the pMCAO rats treated with PROG compared to vehicle. Taken together, these data indicate that PROG is beneficial in one of the best-characterized models of stroke, and may warrant further testing in future clinical trials for human stroke.
Phosphorescence from tryptophan and tryptophan analogs in the solid state

Tryptophan phosphorescence provides a long-lived optical signal whose lifetime and quantum yield are sensitive to the local environment of the protein The phosphorescence from tryptophan analogs, however, has not been studied. We report here data on the room temperature phosphorescence of tryptophan, 4-, 5-, and 6-fluorotryptophan, and 5- bromotryptophan embedded in sucrose glasses. The absorption of the analogs was either blue-shifted (4-F-trp), markedly red- shifted (5-F-trp and 5-Br-trp), or not shifted (6-F-trp) with respect to tryptophan. The phosphorescence emission spectra of all analogs were red-shifted compared to trp (442 nm) with maxima at 446 nm (5-F), 451 nm (6-F), 452 nm (5-Br), and 469 nm (4-F). The 5-F and 6-F analogs had emission intensities similar to tryptophan (relative quantum yields of 0.68 and 0.91, respectively), while the emission intensities of the 4-F and 5-Br analogs were much lower (relative quantum yields of 0.039 and 0.022, respectively). All analogs exhibited complex decay behavior which required several exponentials for an adequate fit. The average lifetimes were all significantly lower than that of trp (2109 ms). The average lifetimes of the fluorinated analogs (5-F: 1496 ms, 6-F: 1004 ms, and 4-F: 87 ms) scaled approximately with the relative quantum yields while that of 5-Br (1.03 ms) was significantly lower.
Double bond migration and racemization during the hydrogenation of olefins

Abstract Double bond migration and racemization during the hydrogenation of several optically active alkenes have been studied. Extensive double bond migration and racemization occur with supported and unsupported palladium catalysts. Most, if not all, of the racemization results from double bond migration. Racemization of the alkenes by other processes was not detected. The rate of double bond migration is reduced markedly by the presence of base.
1,25-Dihydroxyvitamin D3-regulated binding of nuclear proteins to a c-myc intron element

The steroid hormone 1,25-dihydroxyvitamin D3[1,25-(OH)2D3] induces maturation of many cells, including HL-60 promyelocytic leukemia cells that are differentiated to monocytes/macrophages. This process involves changes in transcription of genes such as c-myc. We investigated the effects of 1,25-(OH)2D3 on nuclear protein binding to the c-myc intron element (MIE), a region of DNA within the c-myc gene. A mutation in this MIE sequence has been shown to be associated with uncontrolled expression of the c-myc gene in various cell lines. In this report, we demonstrate for the first time that 1,25-(OH)2D3 induces increased binding of nuclear proteins to this MIE in HL-60 cells. The major MIE-binding proteins were approximately 32 kDa in size. Interestingly, phorbol 12-myristate 13-acetate induced a similar increase in binding of the 32-kDa doublet protein to the MIE. In addition, we showed that the level of 138-kDa MIE-binding protein was increased by 1,25-(OH)2D3 and phorbol 12-myristate 13-acetate. However, th...
Pulmonary oxygen toxicity. Connective tissue changes during injury and repair.

It remains unclear whether the interstitial contractile cells have a significant role in modulating function of the normal lung. Their strategic location in the alveolar wall suggests a role in the control of pulmonary perfusion.' Furthermore, their intimate relationship with the connective tissue matrix would suggest a role in the control of the stiffliess of the alveolar wall. Changes in tone of the cells in response to gas tensions or circulating active compounds could induce rapid and reversible changes of local compliance. The present results support our previous observations of increased con- tractility in strips of fibrotic rat lung.4 They further suggest that the responsiveness of the lung to pharmacologic agents can change as a function of the types of cells populating the interstitium. Both the moderately and severely fibrotic strips contained excessive connective tissue, yet the contractile responses to epinephrine were directly opposite. This indi- cates that the response is a function of cell type and not merely due to changes in the connective tissue matrix. ACKNOWLEDGMENT: The authors wish to acknowledge the assistance of Mrs. Cathy Ward in the preparation of this manuscript.
In search of covalently bound tetra- and penta-oxygen species: a photoelectron spectroscopic and Ab initio investigation of MO4- and MO5- (M = Li, Na, K, Cs).

Although neutral and ionic O40/-/+ species have been observed experimentally and considered for energetic materials, O42- and O52- dianions have not yet been explored. O42- is valent isoelectronic to the well-known ClO3- and SO32- anions, and O52- is valent isoelectronic to ClO4- and SO42-. All are stable, common anions in solutions and inorganic salts. In this article, we explore the possibility of making covalently bound O42- and O52- species stabilized in the forms of M+O42- and M+O52- (M = Li, Na, K, Cs) in the gas phase. Laser vaporization experiments using M-containing targets and an O2-seeded carrier gas yielded very intense mass peaks corresponding to MO4- and MO5-. To elucidate the structure and bonding of the newly observed MO4- and MO5- species, we measured their photoelectron spectra and then compared them with ab initio calculations and the spectra of ClO3-, Na+SO32-, ClO4-, and Na+SO42-. Careful analyses of the experimental and ab initio results showed, however, that the observed species are...
Optical and magneto-optical properties of neodymium and erbium doped gallium nitride epilayers

Following the commercial availability of high power III-nitride light emitting diodes in the 370–540 nm range, a strong desire for efficient rare earth-doped (In)GaN epilayers has developed to produce light source and electrically pumped optical amplifiers in the visible and IR spectral region. To this end, Er-doped GaN epilayers have been grown by OVMPE with excellent crystal quality [1]. Similar success has been achieved with in-situ doped Nd:GaN samples grown by plasma-assisted MBE [2]. For each dopant, we have studied site-selective emission spectroscopy using combined excitation-emission spectroscopy (CEES) to give important insight for the optimization of the growth conditions. Aside from application in novel light sources, there has been an increasing interest in the magnetic properties of the dilute RE-dopants, which are found to introduce ferromagnetism to the GaN host [3] enabling the realization of spin-memory based on this class of material [4].
Site-directed mutations at D1-Thr179 of photosystem II in Synechocystis sp. PCC 6803 modify the spectroscopic properties of the accessory chlorophyll in the D1-branch of the reaction center.

D1-Thr179, which overlies the reaction center chlorophyll ChlD1 of Photosystem II was replaced with His and Glu through site-directed mutation in Synechocystis sp. PCC 6803. Spectroscopic characterization of the mutants indicates that, compared to wild type, the main bleaching in the triplet-minus-singlet absorbance difference spectrum and the electrochromic band shift in the (P680+QA−−P680QA) absorbance difference spectrum are displaced to the red by ∼2 nm in the D1-Thr179His mutant and to the blue by ∼1 nm in the D1-Thr179Glu mutant. These difference spectra are compared with the absorbance difference spectra, measured on the same states in the D1-His198Gln mutant in which the axial ligand D1-His198 of the special pair chlorophyll, PD1, was replaced by glutamine. Together, these results give direct evidence that (a) the reaction center triplet state, produced upon charge recombination from 3[P+Pheo−], is primarily localized on ChlD1; (b) the cation of the oxidized donor P+ is predominantly localized on ...
Guided mentorship in evidence-based medicine for psychiatry: a pilot cohort study supporting a promising method of real-time clinical instruction.

Evidence-based medicine has been promoted to enhance clinical decision making and outcomes in psychiatry. Residency training programs do not routinely provide instruction in evidence-based medicine. Where instruction exists, it tends to occur in classroom settings divorced from the clinical decision-making process and is focused narrowly on appraisal of evidence quality. The goal of this pilot study was to develop and evaluate the promise of a method of “hands-on” instruction in evidence-based medicine done in real clinical time. A modularized curriculum to promote decision-making strategies using evidence-based medicine during the course of actual patient care was delivered by an attending physician mentoringa small team on the inpatient and consultation-liaison psychiatry services at Stanford. A staggered cohort of 24 consecutive trainees was followed between August and January 2007. Measures of trainees’ skills in evidence-based medicine were assessed before and after mentoring. A blinded grader scored each inventory according to an explicit, predefined rubric. Demonstrated proficiency in delivery in each of the core skills of evidence-based medicine was assessed as a secondary outcome measure via the attending physician’s unblinded subjective evaluation of trainee performance. Subjective descriptions of the experience were obtained via review of trainees’ evaluations. Postmeasures of knowledge and skills in evidence-based medicine increased significantly relative to baseline. The Cohen’s d effect size was large and clinically meaningful. The majority of trainees were able to demonstrate adequate proficiency of skills by attending subjective evaluation. Trainees’ subjective experiences overall were positive. Guided mentoring in evidence-based medicine appears promising for further study.
False Claims of Blood Pressure–Independent Protection by Blockade of the Renin Angiotensin Aldosterone System?

In the wake of a number of recent clinical trials, claims that blockade of the renin-angiotensin-aldosterone system (RAAS) provides vascular protective effects that are not simply secondary to reductions in blood pressure (so-called BP-independent effects) have become increasingly popular. How accurate are these kinds of claims? The report by Griffin, Bidani, and coworkers in this issue of Hypertension 1 is one of a series of studies from this group in animal models of hypertension that, together with recent clinical studies by other investigators, have begun to raise serious questions about such claims regarding RAAS blockade. In the current study of RAAS blockade in the stroke-prone spontaneously hypertensive rat (SHRsp) and in previous studies in the remnant kidney model of hypertension, Griffin et al have done something that should be axiomatic for those involved in blood pressure research yet is ironically neglected in many, if not most, clinical and experimental studies of hypertension: they have paid careful attention to obtaining an accurate and thorough assessment of the blood pressure profile. By using radiotelemetry to obtain continuous, 24-hour measurements of blood pressure throughout the course of their studies, Griffin et al have demonstrated that the renoprotection afforded by enalapril or spironolactone in salt-supplemented SHRsp is tightly related to the effects of these agents on blood pressure. These results are similar to their earlier radiotelemetry studies of ACE inhibition or angiotensin receptor blockade in the remnant kidney model of hypertension showing a highly robust relationship between blood pressure and renoprotection that is remarkable when one considers the inherent variability of these complex, biologic phenotypes.2 In their previous studies in which blood pressure profiles were also carefully assessed, Griffin et al demonstrated that other antihypertensive drugs that do not compromise renal autoregulation can provide renoprotective effects that are equivalent to those afforded by …
Escape rates and conditionally invariant measures

We consider dynamical systems on domains that are not invariant under the dynamics—for example, a system with a hole in the phase space—and raise issues regarding the meaning of escape rates and conditionally invariant measures. Equating observable events with sets of positive Lebesgue measure, we are led quickly to conditionally invariant measures that are absolutely continuous with respect to Lebesgue. Comparisons with SRB measures are inevitable, yet there are important differences. Via informal discussions and examples, this paper seeks to clarify the ideas involved. It includes also a brief review of known results and possible directions of further work in this developing subject.
Eliminating the left-brain/right-brain conflict present in the traditional Critical Path Method

In presenting Critical Path Method in the traditional manner, students experience a left-brain/right-brain conflict as they switch back and forth between the network diagram and the table ultimately used to calculate the slack values. For some students, this is not a problem; however, for many students, this is confusing to the point that these students refuse to use one or the other of these two essential tools. I have devised a presentation scheme that eliminates this conflict while simultaneously retaining all of the information content. This paper presents this scheme along with empirical evidence of its efficacy.
Grid interconnection for variable-speed wind farm with multi-level inverter

This paper presents design, modeling, and control of grid interconnection for a wind farm with round-rotor synchronous generators. The grid interconnection proposed in this paper supports the variable-speed wind turbine concept with the three-phase diode bridge as a front-end rectifier. The wind energy resources and the utility grid are isolated by intermediate fly-back converters. The grid interface multi-level inverter with H-bridge converters improves the power quality of the utility grid. The fast transient response of the real and reactive power control is achieved by the feedback control in synchronous rotating reference frame. Stability of the integrated subsystems is also analyzed with the Nyquist criteria and classical control theory. Simulation results with PSCAD in normal operations and short circuit fault operations are illustrated.
Learning direction in global motion: two classes of psychophysically-motivated models

Perceptual learning is defined as fast improvement in performance and retention of the learned ability over a period of time. In a set of psychophysical experiments we demonstrated that perceptual learning occurs for the discrimination of direction in stochastic motion stimuli. Here we model this learning using two approaches: a clustering model that learns to accommodate the motion noise, and an averaging model that learns to ignore the noise. Simulations of the models show performance similar to the psychophysical results.
“Can We Laugh at God?”: Apocalyptic Comedy in Film

(1991). “Can We Laugh at God?”: Apocalyptic Comedy in Film. Journal of Popular Film and Television: Vol. 19, The Catholic Imagination in Popular Film and Television, pp. 81-90.
Effects of calcium, magnesium, and phosphorylcholine on secondary structures of human C-reactive protein and serum amyloid P component observed by infrared spectroscopy.

The secondary structures of human C-reactive protein (CRP) and serum amyloid P component (SAP) in D,Obased solutions in the presence or absence of calcium, magnesium, and phosphorylcholine have been investigated using Fourier transform infrared spectroscopy. Quantitative analysis provided estimations of about 50% @-sheet, 12% a-helix, 24% @-turn, and 14% unordered structure for CRP and about 54% @-sheet, 12% a-helix, 25% @-turn, and 9% unordered structure for SAP. With both proteins significant calcium-dependent changes were observed in conformation-sensitive amide I regions assigned to each type of structure. The CRP spectrum was also af€ected by magnesium, but the changes differed from those induced by calcium. The SAP spectrum was not affected by magnesium. Phosphorylcholine in the presence of calcium also affected the spectrum of CRP but not the spectrum of SAP. Our present study provides the first direct comparison of the secondary structures of the pentraxins human CRP and SAP and hamster female protein (Dong, A., Caughey, B., Caughey, W. S., Bhat, K. S., and Coe, J. E. (1992) Biochemistry 32, 9364-9370). These findings suggest that the three pentraxins have similar secondary structure compositions and calcium-dependent conformational
Applying Knowledge Sharing for Business Intelligence Collaboration

IT services need an automatic and flexible ability to react to dynamic changes in their environment. Managing change effectively and reducing the negative effects of day-to-day operations has become one of the most important tasks in IT service management, which require hiring highly skilled IT professionals with correspondingly high labor costs. There is a challenge to select, implement and integrate the right resources quickly and effectively. Although there is a growing body of research into IT management, many techniques are either too narrow (focusing on a single component rather than the entire system), or they address only configuration data collection and integration. Instead, one needs to scale or respond to special domain knowledge, collaboration and the right data for helping IT professionals to improve their work. In this paper, we propose a knowledge-sharing based collaborating management system for IT service management. It aims to bridge the gap between domain experts’ knowledge and manageable systems. We developed a proof-of-concept of an impact analysis service based on knowledge-sharing; it establishes an IT service management collaboration paradigm and ecosystem, leveraging the expert’s rich knowledge and experience to improve the management quality and reduce the cost. A case study driven by customers demonstrates that collaboration with knowledge sharing is effective both at constructing useful system analysis services and in using those services to improve system management.
Preparation of β-aminoesters from ketene silyl acetals and N-(alkylamino)benzotriazoles

Abstract A wide variety of β-aminoesters are prepared in good yields by the reaction of lithium ester enolates derived from ketene silyl acetals with N-(alkylamino)benzotriazoles. The secondary β-aminoesters readily cyclize to β-lactams (2-azetidinones) on deprotonation.
The BUR1 cyclin-dependent protein kinase is required for the normal pattern of histone methylation by SET2.

BUR1 and BUR2 encode the catalytic and regulatory subunits of a cyclin-dependent protein kinase complex that is essential for normal growth and has a general role in transcription elongation. To gain insight into its specific role in vivo, we identified mutations that reverse the severe growth defect of bur1Δ cells. This selection identified mutations in SET2, which encodes a histone methylase that targets lysine 36 of histone H3 and, like BUR1, has a poorly characterized role during transcription elongation. This genetic relationship indicates that SET2 activity is required for the growth defect observed in bur1Δ strains. This SET2-dependent growth inhibition occurs via methylation of histone H3 on lysine 36, since a methylation-defective allele of SET2 or a histone H3 K36R mutation also suppressed bur1Δ. We have explored the relationship between BUR1 and SET2 at the biochemical level and find that histone H3 is monomethylated, dimethylated, and trimethylated on lysine 36 in wild-type cells, but trimethylation is significantly reduced in bur1 and bur2 mutant strains. A similar methylation pattern is observed in RNA polymerase II C-terminal domain truncation mutants and in an spt16 mutant strain. Chromatin immunoprecipitation assays reveal that the transcription-dependent increase in trimethylated K36 over open reading frames is significantly reduced in bur2Δ strains. These results establish links between a regulatory protein kinase and histone methylation and lead to a model in which the Bur1-Bur2 complex counteracts an inhibitory effect of Set2-dependent histone methylation.
100 years in the dark: Extreme longevity of Eocene bivalves from Antarctica

A combination of sclerochronologic techniques and stable isotope analysis reveals that the fossil bivalve Cucullaea raea , from the Eocene of Antarctica, regularly lived for more than a century. In addition, shell growth occurred only during the Austral winter, when food (phytoplankton) availability was limited by darkness. Although extreme longevity in modern bivalves tends to correlate with cold temperature, paleotemperature conversion of δ18O values indicates that these high-latitude fossil clams lived in relatively warm (∼14 °C) shallow seas of the Eocene greenhouse world. Growth cessation during otherwise optimal summer conditions is inferred to reflect summer spawning and a reproductive strategy by which to increase the likelihood of larval survival in a light-stressed (and hence food stressed) setting. Long life may therefore be adaptive in a setting where the chances of reproductive success during any one spawning cycle are very low. In addition, food limitation may play a role in extending life by reducing metabolic rate and somatic growth, slowing the process of senescence (aging). The unusual life history of this fossil high-latitude, temperate-water bivalve suggests that low light and food availability, as opposed to cold temperature, may have a greater influence on molluscan growth at high latitudes than previously thought.
The PurR regulon in Escherichia coli K-12 MG1655

The PurR transcription factor plays a critical role in transcriptional regulation of purine metabolism in enterobacteria. Here, we elucidate the role of PurR under exogenous adenine stimulation at the genome-scale using high-resolution chromatin immunoprecipitation (ChIP)–chip and gene expression data obtained under in vivo conditions. Analysis of microarray data revealed that adenine stimulation led to changes in transcript level of about 10% of Escherichia coli genes, including the purine biosynthesis pathway. The E. coli strain lacking the purR gene showed that a total of 56 genes are affected by the deletion. From the ChIP–chip analysis, we determined that over 73% of genes directly regulated by PurR were enriched in the biosynthesis, utilization and transport of purine and pyrimidine nucleotides, and 20% of them were functionally unknown. Compared to the functional diversity of the regulon of the other general transcription factors in E. coli, the functions and size of the PurR regulon are limited.
Weakly mixing PET

Suppose that (X, ℬ, μ) is a probability measure space and T is an invertible measure perserving transformation of (X, ℬ, μ). T is called weakly mixing if for any two sets A1A2 ∈ ℬ one has:
Gibbs adsorption isotherm combined with Monte Carlo sampling to see action of cosolutes on protein folding.

Driven by conditions set by smaller solutes, proteins fold and unfold. Experimentally, these conditions are stated as intensive variables - pH and other chemical potentials - as though small solutes were infinite resources that come at an externally varied free energy cost. Computationally, the finite spaces of simulation allow only fixed numbers of these solutes. By combining the analytic Gibbs adsorption isotherm with the computational Monte Carlo sampling of polymer configurations, we have been able to overcome an inherent limitation of computer simulation. The idea is to compute analytically the free energy changes wrought by solutes on each particular configuration. Then numerical computation is needed only to sample the set of configurations as efficiently as when no bathing solute is present. For illustration, the procedure is applied to an idealized two-dimensional heteropolymer to yield lessons about the effect of cosolutes on protein stability. Proteins 2004. © 2004 Wiley-Liss, Inc.
Single-image far-field subdiffraction limit imaging with axicon

This Letter presents a technique for subdiffraction limit imaging termed Bessel beam microscopy (BBM). By placing a lens in series with an axicon in the optical path of a microscope, the diffraction-limited resolution of the base microscope is improved by one third. This improvement is demonstrated experimentally by resolving individual subdiffraction limit fluorescent beads in a close-pack arrangement. The behavior of the BBM system is explored using angular diffraction simulations, demonstrating the possibility of resolving features spaced as little as 110 nm apart when viewed with a 100×1.4 NA objective. Unique among super-resolution techniques, BBM acquires subdiffraction limit information in a single image with broadband unstructured illumination using only static geometric optics placed between the microscope and camera.
Robust incremental SLAM with consistency-checking

Incorrect landmark and loop closure measurements can cause standard SLAM algorithms to fail catastrophically. Recently, several SLAM algorithms have been proposed that are robust to loop closure errors, but it is shown in this paper that they cannot provide robust solutions when landmark measurement errors occur. The root cause of this problem is that the robust SLAM algorithms only focus on generating solutions that are locally consistent (i.e. each measurement agrees with its corresponding estimates) rather than globally consistent (i.e. all of the measurements in the solution agree with each other). Moreover, these algorithms do not attempt to maximize the number of correct measurements included in the solution, meaning that often correct measurements are ignored and the solution quality suffers as a result. This paper proposes a new formulation of the robust SLAM problem that seeks a globally consistent map that also maximizes the number of measurements included in the solution. In addition, a novel incremental SLAM algorithm, called incremental SLAM with consistency-checking, is developed to solve the new robust SLAM problem. Finally, simulated and experimental results show that the new algorithm significantly outperforms state-of-the-art robust SLAM methods for datasets with incorrect landmark measurements and can match their performance for datasets with incorrect loop closures.