cssi/SciSciGPT-SciSciNet huggingface dataset:
High resolution quantitation of microvascular plasma perfusion in non-ischemic and ischemic rat brain by laser-scanning confocal microscopy.

Laser-scanning confocal microscopy (LSCM) was used to measure at high resolution cerebral plasma volumes (perfusion) using two fluorescent plasma markers in a rat model of embolic stroke. This application of LSCM to study the microvascular circulation in embolic stroke was developed as an alternative to autoradiography to measure cerebral perfusion. An additional benefit of LSCM is that it quantitates with great accuracy the structural relationships of the microcirculation to cells and the pathological alterations of the ischemic brain. Autoradiography allows only a quantitative analysis of cerebral perfusion. For example, in order to study the microcirculation and its relationship to blood brain barrier damage, the volume of perfused cerebral capillaries was measured by administering two fluorescent plasma markers (FITC-dextran and Evans blue) intravenously to a rat. Evans blue was administered before cerebral ischemia and FITC-dextran administered post-ischemia 1 min before sacrifice. Volumes of plasma perfusion were analyzed by means of a system developed for 3D analysis of fixed and stained serial brain histologies. Plasma volumes for the non-ischemic cerebral cortex were 1.00%+/-0.38% while plasma volumes in the caudate/putamen were 0.69%+/-0.17% in good agreement with the previously published values using the autoradiography method. The architecture of the capillaries in the ischemic core showed perfusion of Evans blue but there was no flow of FITC dextran. Our work represents a novel application of this technology to investigation of cerebral vascular disease and identifies its potential to become an important tool for investigation of cerebral pathology.
THE SEQUELAE OF HEPATITIS.

The characteristics and suggested management of several sequelae of hepatitis are enumerated and discussed, giving the author's own views as developed in clinical practice.
Regional assignment of the structural gene for human acid β-glucosidase to q42→qter on chromosome 1

The structural gene for human acid β-glucosidase (GBA) has been regionally assigned to a narrow region on chromosome 1 using somatic cell hybridization, specific immunoprecipitation, and assay with th
Clinical predictors and impact of ambulatory blood pressure monitoring in pediatric hypertension referrals

Elevated blood pressure (BP) is rising in children. Significant proportions of children have reactive hypertension or masked hypertension, making ambulatory BP monitoring (ABPM) a valuable tool, although with potential economic implications. In youth referred for elevated BP, we sought clinic BP combinations that obviated the need for ABPM and to specify the economic role of ABPM. In a retrospective pediatric referral cohort (N = 170), we examine clinic systolic BP (SBP) predictors of components of ABPM hypertension and their combination. In economic analyses, we compared effectiveness and charges of three diagnostic pathways: (1) clinic BP alone; (2) abnormal clinic BP prompting ABPM; or (3) universal ABPM. ABPM hypertension occurred in 55 (32.4%) and reactive hypertension in 37 (21.8%), average automated (β = 0.208; 95% confidence interval, 0.027, 0.389; P = .03) and maximum auscultatory clinic SBP (β = 0.160; 95% confidence interval 0.022, 0.299; P = .02) were associated with ABPM SBP mean, but none predicted SBP load. No clinic SBP combination was associated with ABPM hypertension. Universal ABPM accrued the lowest average charge per hypertensive youth identified ($10,948). We did not identify a clinic SBP combination that predicted ABPM hypertension in youth referred for elevated BP. Universal ABPM, in this context, may be the most economically and clinically efficient diagnostic strategy.
Building a valid web service composition using integrated service substitution and adaptation

Traditional web service composition is often statically generated using knowledge available at the design time. In addition, they assume the final composition workflows are always executable. However, this assumption might be false since the environment can change during the execution time. Therefore, it is essential that the correctness of a partial/full composition needs to be validated and maintained during its execution. This paper utilises the notion of workflow exception handling to generate valid web service compositions. More specifically, we propose the concepts of synchronous exception handling and asynchronous service interrupt (ASI). The synchronous workflow exception is used in the initial service configuration which contains static service substitution, planning time-service adaptation and mapping time-service adaptation, while the ASI is implemented via dynamic service substitution and binding time-service adaptation. The integrated usage of the above approaches is demonstrated by an implementation of an e-hospital application.
Drug-induced phase change in bilayer as possible mode of action of membrane expanding drugs.

MANY small molecules modulate membrane functions. Substances such as neurotransmitters interact directly with specific protein receptor sites, whereas others such as anaesthetics, interact with membrane lipids or with hydrophobic regions of membrane. This is consistent with a correlation of their activity with their lipid solubility and lipid–water partition coefficient1. Several lipid-soluble drugs are antihaemolytic2, which correlates not only with their pharmacological activity but also with their ability to expand the lipid bilayer of a biomembrane3. Although expansion of bilayers implies a drug-induced reorganisation of lipids, the mechanism involved remains to be established. We now have evidence that the lipid-soluble drugs may induce a transition of lipid acyl chains from organised gel to randomised liquid crystalline phase. Such drug-induced changes in the lipid phase in a bilayer may affect the function of various membrane-bound proteins4.
Thermal aging of heterophasic propylene-ethylene copolymers : spatial and temporal aspects of degradation based on ESR, ESR imaging, and FTIR

Heterophasic propylene−ethylene copolymers (HPEC) containing bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (Tinuvin 770) as a hindered amine stabilizer (HAS) were thermally aged at 393 and 433 K....
Autoradiography with acrylamide gel slab electrophoresis.

Abstract A method for electrophoresis and autoradiography with a multisample gel slab system has been described. The method obviates slicing of the gel, retains the high degree of resolution of bands in the autoradiogram, and enables comparison of protein and radioactivity patterns of many samples under essentially identical conditions. Within a limited range, a linear relation is obtained between radioactivity and optical density in the autoradiogram, as well as between protein concentration and optical density in the gel.
Regulation of phosphoinositide-specific phospholipase C.

Abstract The receptors involved in the regulation of phospholipase C by hormones, neurotransmitters and other ligands have seven transmembrane-spanning hydrophobic regions (seven-helix motif) and no known enzymatic activity. Furthermore these receptors can be isolated as complexes with guanine nucleotide binding (G) proteins. Guanine nucleotides affect the binding of hormones that stimulate phospholipase C and it has been possible to see activation of GTPase activity in membranes upon addition of these ligands. Further indirect evidence for a G p (p stands for phospholipase C activation) protein is the finding that in membranes agonist activation of phospholipase C requires the presence of GTPγS a non-hydrolyzable analog of GTP. Furthermore, fluoride is able to activate phospholipase C but its inhibition of phosphatidylinositol-4′ kinase (PI-4′ kinase) can interfere with efforts to demonstrate this in intact cells. There are four major isozymes of phospholipase C that have been cloned and sequenced. Recently it was found that phospholipase C-γ as well as PI-3′-kinase are substrates for phosphorylation on tyrosine residues by the EGF and PDGF receptors. The PI-3′ kinase is able to convert phosphatidylinositol 4,5-bisphosphate (PIP 2 ) to phosphatidylinositol 3,4,5-trisphosphate (PIP 3 ) but the function of this lipid is unknown since it is not a substrate for any known phospholipase C. While much has been learned about the structure and regulation of the phosphoinositide specific kinases and phosphodiesterase enzymes this is a relatively new field in which we can expect many advances during the next few years.
New method of lifetime prediction for brittle fracture of polyethylene

A new method for predicting the time to brittle failure of polyethylenes is proposed. The method includes modeling slow crack growth in polyethylenes and the experimental determination of material parameters for the model. The model is based on the concept of the crack layer, i.e., a system consisting of the strongly interacting crack and process zone and the kinetic equations which govern the crack layer growth. The process zone in polyethylenes usually appears to be a thin strip of drawn material extending along the crack line. This permits a characterization of the crack layer by two parameters: the crack and process zone lengths. The two-parameter crack layer kinetic model allows description of slow crack growth as the discontinuous (stepwise) process which is commonly observed in the brittle fracture of polyethylenes. The model also predicts a relationship between time to failure and applied stress, identical to that established experimentally. The material parameters of the kinetic model can be determined by experiments on smooth specimens, i.e., are independent of slow crack growth and require relatively short-term observations. Thus, the combination of the material testing and the mathematical modeling of the crack layer evolution is proposed as a method for lifetime prediction in the brittle fracture of polyethylenes. © 1995 John Wiley & Sons, Inc.
Graded symmetry and Anderson localization on the Bethe lattice for time-reversal invariant systems

Abstract We study the phenomenon of Anderson localization on a Bethe lattice via a supersymmetric nonlinear σ-model. We consider the time-reversal invariant case and compare our results to the technically simpler time-reversal noninvariant case. We found that the properties of the two cases are very similar. In particular, the density-density correlation function follows from the solution of a one-dimensional integral equation with a kernel having the same gross properties as in the time reversal noninvariant case. The inverse participation ratio is discontinuous at the transition point. The distance dependence of the density-density correlation function is derived with the help of the theory of random walks. Results have been supported and extended by numerical calculations. Due to elaborate grassmannian integrals no results have been obtained for the extended phase.
Zero differential resistance in two-dimensional electron systems at large filling factors

We report on a state characterized by a zero differential resistance observed in very high Landau levels of a high-mobility two-dimensional electron system. Emerging from a minimum of Hall field-induced resistance oscillations at low temperatures, this state exists over a continuous range of magnetic fields extending well below the onset of the Shubnikov\char21{}de Haas effect. The minimum current required to support this state is largely independent on the magnetic field while the maximum current increases with the magnetic field tracing the onset of inter-Landau level scattering.
Cardiac abnormalities in the Rubinstein-Taybi syndrome

In order to evaluate the incidence of cardiac anomalies, type of cardiac defects, and their impact in the Rubinstein-Taybi syndrome (RTS), a questionnaire study was done. Forty-five of 138 patients in the study (32.6%) had a known cardiac abnormality; 27 patients had single defects including atrial septal defect (ASD), ventricular septal defect (VSD), patent ductus arteriosus (PDA), coarctation of the aorta, pulmonic stenosis, or bicuspid aortic valve. Eight of these individuals had spontaneous resolution of their problems, while 8 required surgery. Sixteen patients had complex congenital heart defects or two or more abnormalities. Two patients had spontaneous resolution, while 7 required surgery. Surgery is planned in 5 additional patients. Five patients had conduction abnormalities. Individuals with congenital heart defects did not have a higher incidence of other birth defects. The significant incidence and potential severity of cardiac anomalies in our patients suggest that a cardiac evaluation should be strongly considered in patients with RTS.
Exact occupation statistics for one-dimensional arrays ofλ-bells

Exact relationships are developed which describe the exact occupation statistics for one-dimensional arrays ofλ-bells. (Hereλ refers to the number of contiguous compartments occupied by a particle;λ=2 for dumbbells). These relationships are consistent with those calculated using the Bethe approximation in the case when the number of nearest neighbors is two. A partition function which includes the influence of the configurational correlation inherent in a one-dimensional array ofλ-bells is also derived and discussed.
Urban infrastructure security

Abstract This note presents objectives for protecting people from terrorist attack and discusses some recent trends in physical protection, the importance of a rational basis for security strategies, and the need for robust institutions with well-qualified people in critical positions to carry them out. It advocates a holistic strategy that incorporates technology, people, and institutions to achieve long-term security as well as possible ancillary mitigation benefits from other hazards.
Long-term effects of off-road vehicle traffic on tundra terrain

Abstract Traffic tests were conducted at two sites in northern Alaska with an air cushion vehicle, two light tracked vehicles, and three types of wheeled Rolligon vehicles. The traffic impact (surface depression, effect on thaw depth, damage to vegetation, traffic signature visibility) was monitored for periods of up to 10 years. Data show the immediate and long-term effects from the various types of vehicles for up to 50 traffic passes and the rates of recovery of the active layer. The air cushion vehicle produced the least impact. Multiple passes with the Rolligons caused longer-lasting damage than the light tracked vehicles because of their higher ground contact pressure and wider area of disturbance. Recovery occurs even if the initial depression of the tundra surface by a track or a wheel is quite deep (15 cm), as long as the organic mat is not sheared or destroyed.
Pulsar Beams—Big and Bright

The standard picture of a pulsar, or rotation-powered neutron star, has narrow beams of radiation lancing out of the magnetic poles and sweeping across the sky as the star spins. For nearly 50 years, astronomers have been observing radio flashes from these objects and, on the whole, this lighthouse model does a good job of explaining pulsar phenomenology. However, we have not fully deciphered the pulsar mechanism—although we understand how pulsars pulse, we still seek to understand how they shine.
The pyrimido-pyrimidine derivatives RA 233 and RX-RA 85 affect growth and cytoskeletal organization ofrat mammary adenocarcinoma cells☆

Abstract The pyrimido-pyrimidine derivatives RA 233 and RX-RA 85, which are potent inhibitors of platelet and tumor phosphodiesterase, were developed as antitumor agents. When tested by us, these drugs were cytostatic at low concentrations and produced dramatic changes in cell shape and organization of cytoskeletal structures in cultured MTF7 cells derived from the rat 13762NF mammary adenocarcinoma. At high concentrations (up to 600 μg/ml) RA 233 was cytostatic but not cytotoxic to MTF7 cells during a 24 hr incubation in vitro, whereas RX-RA 85 was cytotoxic at concentrations above 4 μg/ml. These drugs caused MTF7 cells to elongate and form numerous vacuoles, which surrounded the cell nucleus. Treatment of MTF7 cells with RA 233 or RX-RA 85 enhanced microtubular organization concomitant with a decrease in microfilament organization. In contrast, treatment of MTF7 cells with 1 mM dibutyryl cAMP resulted in an enhanced organization of microtubules but had no effect on microfilament organization. Previous studies that RA 233 and RX-RA 85 increase cAMP levels in 2 other cell clones of rat 13762NF mammary adenocarcinoma by inhibiting phosphodiesterases. However, additional sites of drug action should also be considered based on the effect of these drugs on microfilament systems and cell vacuoles.
Correlates of Early Hospital Readmission or Death in Patients With Congestive Heart Failure

Abstract Among patients with heart failure who survive an admission to the hospital, those who are readmitted or die soon after discharge may warrant special attention. Therefore, we prospectively followed 257 patients admitted nonelectively to an urban university hospital, with a complaint of shortness of breath or fatigue and evidence of congestive heart failure on admission chest radiograph, who were discharged alive. Through survey of patients and families, review of the hospital computer system, and a search of the National Death Index, we recorded death and hospital readmission. Within 60 days of discharge, 13 patients (5%) died and 82 (32%) died or were readmitted to the hospital. Using Cox proportional-hazards modeling, the multivariable correlates of readmission or death were single marital status (adjusted hazard ratio [HR] 2.1, 95% confidence interval [CI] 1.3 to 3.3), Charlson Comorbidity Index score (HR 1.3 per point to maximum 4 points, 95% CI 1.1 to 1.6), admission systolic blood pressure of ≤100 mm Hg (HR 2.8, 95% CI 1.6 to 5.0), and absence of new ST-T-wave changes on the initial electrocardiogram (HR 1.9, 95% CI 1.1 to 3.3). Self-reported patient compliance and clinical instability at discharge were not correlates. Almost all patients stratified by these factors had at least a 25% risk of readmission or death. Our independent correlates of readmission or death support the importance of both medical and social factors in the pathway to clinical decline. However, we could not reliably identify a truly low-risk group. Interventions to decrease early readmission or death among patients with heart failure should target both medical management and the adequacy of social support, and probably need to be applied to all admitted patients. To determine correlates of early readmission or death, we prospectively followed 257 patients admitted to an urban university hospital with a complaint of shortness of breath or fatigue and evidence of congestive heart failure on admission chest radiograph. Single marital status, increasing comorbidity, relative hypotension, and absence of new ST-T-wave changes on initial electrocardiogram were the correlates, but we could not reliably identify a truly low-risk group.
Radial Distribution Functions and their Role in Modeling of Mixtures Behavior

Abstract Radial distribution (Pair correlation) functions are the primary linkage between macroscopic thermodynamics properties and intermolecular interactions of fluids and fluid mixtures. Numerous theories of mixtures exist based on the definition of the radial distribution functions. Utilization of such theories require the knowledge about mixture radial distribution functions and their relations. Generally the exact radial distribution functions of real fluid mixtures are not available. In this paper a number of approximations for the mixture radial distribution functions are presented. Application of these approximation can result in analytic mixture theories and mixing rules. A uniform statistical mechanical technique is presented through which one can derive equation of state mixing rules based on different RDF approximations. The relative merits of different sets of mixing rules derived by this technique and their applications for modeling of the behavior of mixtures are discussed.
On Decision Making in Arranged Marriages with a Stochastic Reservation Quality Level

Recently, Batabyal (1999) has shown that when the decision to get married in an arranged marriage is analyzed in an intertemporal and stochastic setting, it is possible that a marrying agent will never get married. This result arises because the marrying agent in Batabyal (1999) maximizes the probability of accepting the best possible marriage proposal. What happens when a marrying agent uses the following decision rule: Get married as long as the quality of a marriage proposal exceeds a stochastic reservation quality level? In this note, we provide an interesting answer to this question. First, we show that the probability of getting married with this decision rule is always positive. Even so, we point out that on average, an agent who uses this decision rule will end up single.
Free energies and mechanisms of water exchange around Uranyl from first principles molecular dynamics

From density functional theory (DFT) based ab initio (Car-Parrinello) metadynamics, we compute the activation energies and mechanisms of water exchange between the first and second hydration shells of aqueous Uranyl (UO{sub 2}{sup 2+}) using the primary hydration number of U as the reaction coordinate. The free energy and activation barrier of the water dissociation reaction [UO{sub 2}(OH{sub 2}){sub 5}]{sup 2+}(aq) {yields} [UO{sub 2}(OH{sub 2})4]{sup 2+}(aq) + H{sub 2}O are 0.7 kcal and 4.7 kcal/mol respectively. The free energy is in good agreement with previous theoretical (-2.7 to +1.2 kcal/mol) and experimental (0.5 to 2.2 kcal/mol) data. The associative reaction [UO{sub 2}(OH{sub 2}){sub 5}]{sup 2+}(aq) + H{sub 2}O {yields} [UO{sub 2}(OH{sub 2})6]{sup 2+}(aq) is short-lived with a free energy and activation barrier of +7.9 kcal/mol and +8.9 kca/mol respectively; it is therefore classified as associative-interchange. On the basis of the free energy differences and activation barriers, we predict that the dominant exchange mechanism between [UO{sub 2}(OH{sub 2}){sub 5}]{sup 2+}(aq) and bulk water is dissociative.
On the Proximity of Algebraic Units To Divisors

Abstract An asymptotic formula counting algebraic units with respect to a proximity function on the group variety is given. The proximity function measures the local distance to a divisor on the variety. The formula allows a natural definition of mean distance between the group and the divisor. By allowing the divisor to vary a description of the way global units are decorated around local geometric configurations follows. Inevitably, Leopoldt′s conjecture is encountered. Some special cases of the mean value are calculated illustrating a dependence upon the p-adic regulator. The main techniques in this research are Baker′s theorem, in its archimedean and p- adic versions, and the theory of uniform distribution of sequences.
Geoid information by wavelength

Two models describing potential coefficient behavior are used to estimate the root mean square geoid undulation by wavelength. Four wavelength types were defined: long wavelengths: l=2 to 10; intermediate wavelengths: l=11 to 100; short wavelengths: l=101 to 1000; and very short wavelengths: l=1001 to ∞. By one representation of potential coefficient behavior the intermediate wavelength geoid information was ±5.64 m, short wavelength, ±0.66 m, and the very short wavelength, ±0.05 m. The procedures of this paper were applied to an actual residual undulation computation using detailed gravity material.
Design and Numerical Simulation of a New Sandwiched Sphere Structure for Ballistic Protection

Abstract Sphere structures for ballistic protection have rarely been studied. In this paper a novel unit cell, called Square Based Pyramid Unit Cell (SBPUC), is created as a fundamental building block of sphere structures for the purpose of ballistic protection. Although it has been proved by the other authors that the arrangement of spheres in a tapered chain is an efficient way for impact energy absorption (Sokolow A, Pfannes JM, Doney RL, Nakagawa M, Agui JH. Absorption of short duration pulses by small, scalable, tapered granular chains. Appl Phys Lett 2005;87:1–3), it is very difficult to convert this 1D concept to 3D application in reality with arbitrary tapering angle. The adoption of SBPUCs may provide a good solution. In this research, the core of a sandwiched sphere structure is build with such SBPUCs and is characterized with increasing sphere diameter, decreasing sphere thickness, and increasing sphere cap thickness. From the numerical simulation results with ABAQUS/Explicit, the sandwiched sphere structure can absorb at least 11.6% more impact energy compared with the monolithic plate with the same area density. This study might provide a potential armor design platform which makes further performance improvement possible by optimizing the large parameter space associated with material selection and structure design.
Commentary on the Article by Turner

According to an International Civil Aviation Organization (2009) global forecast, North America is uniquely cited as the only region in the world with a projected surplus in pilot training capacity...
Nerve transfers in the upper extremity

Abstract Complex upper-extremity nerve injuries are a challenging problem for the reconstructive hand surgeon. Traditionally, nerve grafts or tendon transfers have provided options for restoration of function. Advances in nerve repair and in the understanding of the internal topography of the nerve have contributed to the development of the use of nerve transfers. Nerve-to-nerve transfers offer a superior alternative for functional restoration in isolated or multiple nerve injuries when early reinnervation of the target end organ is necessary, such as in proximal injuries or in delayed treatment. Expendable sensory or motor axons close to the end organ allow for earlier regeneration and preclude the need for nerve grafts. Assessment and criteria for nerve transfers as well as the management, surgical techniques, and outcomes for well-established nerve transfers are described.
In Vitro Drug Release from Matrix Tablets Containing a Silicone Elastomer Latex

AbstractA silicone elastomer latex was evaluated as a wet-granulating agent in preparing controlled release matrix tablets containing a water soluble active ingredient. A one-half fractional factorial statistical design was used to investigate the effect of five different formulation and non-formulation variables on the in vitro release characteristics of the drug from the matrix tablets. Tablets containing a high percent of fumed colloidal silica exhibited a faster drug release rate. A high drug to polymer ratio in the tablets was also shown to result in a faster release of the drug. Granules dried at a higher temperature (80°C vs. 60°C) produced tablets with a slower drug release rate. The release of the drug was shown to be pH dependent. A higher drug release rate was obtained in a dissolution medium with a lower pH (1.2 vs. 6.8).
Comment on “group shift to caution at the race track”

Abstract A recent study by McCauley, Stitt, Woods, and Lipton on the effects of three-person group discussions at the race track claims a systematic shift toward greater caution in betting choices, a result in contrast with the typical laboratory finding of group risky shifts. This study is criticized for an apparent statistical oversight. It is quite plausible that an apparent cautious shift could have arisen as an artifact of the distribution of original positions of the bettors being skewed in the risky direction. This type of potential artifact has been discussed before in the risky shift literature, but is especially stark in the present context. It is recommended as standard procedure for the present data and other similar data that initial group position be indexed with the median rather than the mean, or that other precautions be taken to eliminate the confounding effects of skewness on the assessment of risky or cautious group shifts.
Dosimetric properties of a scanned beam microtron at low monitor unit settings: importance for conformal therapy.

The dosimetric stability, linearity, dose rate dependence, and flatness of both photon and electron beams have been evaluated for a racetrack microtron at low monitor unit settings. For photons, the variation in dosimetric output about the mean is <0.4% at 100 monitor units (MU), <1% at 10 MU, and <4% at 2 MU. The output dependence on the dose rate varied by <0.6% between 85–300 MU/min. Flatness and symmetry for the 25‐ and 50‐MV beams showed deviations of <3% at both d max and 10‐cm depths, and only slightly ≳3% at 20 cm, even at only 3 MU, in contrast with other scanned beam accelerators. Broad electron beams on the microtron are created by the superposition of the elementary beam pulses either directly from the scan magnets, or after their broadening through a scattering foil. The dosimetric instability both with and without the foil was less than 0.6% for both the 25‐ and 50‐MeV electrons. Dose nonlinearity was <1% above 10 MU. Field flatness was determined for scan matrices designed to produce a flat field both with and without a scattering foil. Symmetry and flatness deviations were <3% for both electron energies when a scattering foil was used, even for a single scan. The variation of the electron dose per monitor unit between dose rates of 85–300 MU/min was <1% (25 MeV) and <4% (50 MeV) when a scattering foil was used, but as high as 22% (25 MeV) and 36% (50 MeV) for broad beams generated by elementary beam pulses directly from the scanning magnets. The microtron exhibits dosimetric properties which fulfill the recommendations of Task Groups 21 and 25. Based on the stability of the scanned beam at low monitor unit settings, the microtron can be used for 3‐D conformal therapy with both photons and electrons.
Methyl, hydrochalcogenido, and phenylchalcogenolate complexes of zinc in a sulfur rich coordination environment: syntheses and structural characterization of the tris(2-mercapto-1-tert-butylimidazolyl)hydroboratozinc complexes [TmBut]ZnMe, [TmBut]ZnEH (E = S, Se) and [TmBut]ZnEPh (E = O, S, Se, Te)

A series of hydrochalcogenido and phenylchalcogenolate complexes of zinc supported by tris(2-mercapto-1-tert-butylimidazolyl)hydroborato ligation, [TmBut]ZnEH (E = S, Se) and [TmBut]ZnEPh (E = O, S, Se, Te) have been synthesized from [TmBut]ZnMe; structural characterization by X–ray diffraction indicates that the variation in Zn–E bonding as a function of the chalcogen is significantly different from that in other series of metal–chalcogenolate compounds.
Hole localization in high-temperature superconductors

Abstract Although it is generally assumed that the holes associated with oxygen-doping of high-temperature superconductors (i) are free, (ii) leave the “charge-reservoir” region of the dopant oxygen, and (iii) migrate to cuprate planes where they produce superconductivity and increase the critical temperature, we find evidence of hole localization (of different types) in Tl2Ba2Can−1CunO2n+4+δ and HgBa2Can−1CunO2n+2+δ. We also find that electrons, not holes, transfer to the cuprate planes as pressure or chemical pressure is applied to HgBa2Can−1CunO2n+2+δ, which also causes the critical temperature to increase.
Determination of a glycine/NMDA receptor antagonist in human plasma and urine using column-switching high-performance liquid chromatography with ultraviolet, fluorescence and tandem mass spectrometric detection

Abstract High-performance liquid chromatography (HPLC) assays using ultraviolet (UV) and fluorescence (FL) detection were developed and compared with a liquid chromatography/tandem mass spectrometry (LC/MS-MS) method for determination of the glycine receptor antagonist 7-chloro-4-hydroxy-3-(3-phenoxy)phenyl-2(1H)-quinolone (L-701, 324, I) in human plasma and urine. The drug and internal standard (II) were isolated from the biological matrix through liquid-liquid extraction. In the HPLC-UV and HPLC-FL methods, the samples were initially injected onto a Cyano BDS Hypersil column, and the chromatographic region containing the peaks of interest was heart-cut onto an analytical C-18 BDS Hypersil column via a column-switching device. The analyte was quantified by monitoring either absorbance at 226 nm or fluorescence at 385 nm following 230 nm excitation. The limit of quantitation for I extracted from 1 ml of plasma or urine was 5 ng ml−1, and the assays were validated in the concentration range of 5–200 ng ml−1. The LC/MS-MS method also utilized a column-switching protocol and was validated in the concentration range of 1–200 ng ml−1. Both assays provided data with precision and accuracy within less than 10% for all points in the standard curve range.
Abstract 4703: Lack of expression of argininosuccinate synthetase in human cancer tissue: A biomarker for sensitivity to arginine depletion with pegylated arginine deiminase

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC There is increasing awareness of metabolic abnormalities in cancer that can be exploited with new forms of treatment. In addition, there is a need for biomarkers that would help select such tumors for targeted therapies. One such metabolic abnormality is the requirement of arginine for growth by certain cancers. These cancers lack expression of argininosuccinate synthetase (ASS), the rate limiting step in the metabolism of citrulline to arginine in the Krebs urea cycle, and must obtain arginine from the circulation. It has previously been shown that hepatocellular carcinoma and metastatic melanoma have a high frequency of lack of expression of ASS. As a result, these cancers are susceptible to arginine deprivation with pegylated arginine deiminase (ADI-PEG 20) both in pre-clinical models and in phase 2 clinical trials. Similar lack of ASS expression in human tissue samples and sensitivity to arginine depletion with ADI-PEG 20 in pre-clinical models have been found in a high percentage of pancreatic, prostate, and platinum-resistant ovarian cancers. In order to explore potential other cancers that may lack ASS expression we have examined breast, lung and gastric cancer microarray samples for ASS expression by immunohistochemistry. Our results indicated that 46/111 (41.4%) breast carcinoma, 28/90 (31.1%) lung carcinoma and 68/121 (56.2%) gastric cancer were ASS negative. To explore this further, a panel of 40 ATCC tumor cell lines representing 12 different human cancer types were screened for ADI-PEG 20 induced growth inhibition using the MTS assay. Significant inhibition of proliferation in a dose dependent manner after 48 hours of ADI-PEG 20 treatment was found in 19 out of 40 tumor cell lines screened, including breast, lung, gastric, sarcoma, ovarian, prostate and pancreatic carcinomas and chronic myelogenous leukemia. Lack of ASS expression in those responding cell lines were confirmed by Western blot. These findings suggest that ASS may serve as a biomarker for targeted therapy with ADI-PEG 20. Since a high percentage of patients with breast, lung or gastric cancer lack expression of ASS, these tumors may be sensitive to arginine depletion therapy. Clinical trials of ADI-PEG 20 in these cancers are being planned. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4703.
Quantitative surface characterization using X-ray photoelectron spectroscopy

Use of X-ray Photoelectron Spectroscopy (XPS) for quantitative surface analysis is reviewed. Examples chosen are from our research on heterogeneous catalysts. XPS is useful for measuring distributions of oxidation states because of significant chemical shifts for many elements. However, linewidths complicate analysis of mixtures, necessitating the use of data analysis methodology. Use of factor analysis or deconvolution with non-linear least squares curve fitting gives useful protocols. Five important questions are posed, and some examples of solutions are presented: 1) How many components are present? 2) Where are they located? 3) What do they look like? 4) How much of each component is present? 5) How good is the answer?
Calcium channel blockers: Consensus amid controversy

PREVIEWAlthough the calcium channel blockers have been used to treat hypertension for a number of years, they are now under close scrutiny because of disturbing findings regarding their safety. Drs Kochar and Qurashi sort out the controversies surrounding these widely used drugs and make recommendations based on current consensus.
Springs and Speeds in Free Energy Reconstruction from Irreversible Single-Molecule Pulling Experiments†

The nonequilibrium work relation allows for the calculation of equilibrium free energy differences between states based on the exponential average of accumulated work from irreversible transitions. Here, we compare two distinct approaches of calculating free energy surfaces from unidirectional single-molecule pulling experiments: the stiff spring approximation and the Hummer-Szabo method. First, we perform steered molecular dynamics simulations to mechanically stretch the model peptide deca-alanine using harmonic potentials with different spring stiffnesses and at various constant pulling velocities. We then calculate free energy surfaces based on the two methods and their variants, including the first and second cumulant expansion of the exponentially weighted work and the Gaussian position approximation for the delta function in Hummer and Szabo's expression. We find that with large harmonic force constants, the second cumulant expansion performs well in conjunction with either the stiff spring approximation or the Hummer-Szabo method. When interpreting dynamic force spectroscopy (pullings at different speeds), the second cumulant expansion of the stiff spring approximation performs the best when pulling velocities are similar, but variants of the Hummer-Szabo perform the best when they are spread over a large spectrum. While these conclusion are not definitive for all systems, the insights should prove useful for scientists interpreting nonequilibrium pulling experiments.
An example of the Peleg and Yaari economy

The purpose of this note is to present an example of a Peleg-Yaari [13] exchange economy. The example uses the order properties of the commodity space to concentrate the analysis on the principal ideal A,o generated by the endowment vector co. This will illustrate an idea of Aliprantis, Brown and Burkinshaw [1, p. 142]. They observe that if 8 is an exchange economy with Riesz dual system (E,E') , then the characteristics of ~~ restricted to A,o-define a new exchange economy with Riesz dual system (A,o, A~). Underlying every exchange economy with Riesz dual system (E, E'), there is an exchange economy with the same preferences and endowments and with (A~,, A~) as the commodity-price duality? The example will also illustrate the methods developed by Boyd [8, 9] to study recursive utility functions. The most important point about this example is that it shows how the order structure can be used to get the existence of Pareto optimal allocations and the second welfare theorem in a model that could not generate those results on the larger commodity space of all sequences of real numbers. Beals and Koopmans [6] gave an example of a utility function that is not continuous on the space of all real sequences. Their example is given below as (B1). However, the Beals and Koopmans example is continuous on a subset of the commodity space; this smaller set contains the principal ideal Ao, generated by the endowment vector. The restriction of the model to A,o is also in the spirit of Back's [5] exchange economy model where consumption sets may be strictly contained in the positive cone of the commodity space. My focus is on the second welfare theorem, so I will not assign endowments to consumers.2 The social endowment or a99reoate endowment vector is denoted co.
Vitamin D: Popular Cardiovascular Supplement but Benefit Must Be Evaluated

Vitamin D deficiency is considered to be present in a significant proportion of the general population of the United States. Increasing data suggest that low levels of vitamin D may be associated with increased risk for cardiovascular (CV) disease. The causes of deficiency and what vitamin D levels equate with significant deficiency must be considered. Another major issue is replacement or supplementation doses to be recommended for vitamin D. Secondary effects of the vitamin must be considered because some of the observed effects may explain cardiovascular risk and others may elucidate mechanisms of benefit. Also, there are other reported possible benefits of the vitamin, the significance of which must be assessed. Vitamin D supplementation appears to be generally safe in the doses evaluated in clinical studies, but outcomes data that prove clinical efficacy are still lacking.
A study on the structure and mechanical behavior of the Terrapene carolina carapace: A pathway to design bio-inspired synthetic composites

Abstract The multiscale structure, materials properties, and mechanical responses of the turtle shell (Terrapene carolina) were studied to understand the fundamental knowledge of naturally occurring biological penetrator-armor systems. The structure observation and chemical analysis results revealed that the turtle shell carapace comprises a multiphase sandwich composite structure of functionally graded material having exterior bone layers and a foam-like bony network of closed-cells between the two exterior bone layers. Although the morphology was quite different, the exterior bone layers and interior bony network possessed comparable hardness and elastic modulus values of ~ 1 GPa and ~ 20 GPa, respectively. Compression and flexure test results showed a typical nonlinear deformation behavior recognizant of man-made foams. The mechanical test results revealed that the interior closed-cell foam layer plays a significant role on the overall deformation behavior of the turtle shell. The finite element analysis simulation results showed comparable agreement with the actual experimental test data. This systematic study could provide fundamental understanding for structure-property phenomena and biological pathways to design bio-inspired synthetic composite materials.
Chromatin Organization in E.coli

Prokaryotic organisms must strike a balance between DNA accessibility and condensation: facilitating the genetic processes of transcription, replication, and DNA repair while simultaneously enabling the structural and physical processes of chromosome condensation and segregation in rapidly dividing cells. Recent studies have revealed that prokaryotic chromosomes are intricately structured but the mechanism for this physical organization is not yet understood. In this study, we describe the construction of a large number of E.coli strains carrying three spectrally distinct, fluorescently labeled genetic loci. The origin and terminus of replication as well as a random position on the chromosome are labeled and tracked simultaneously in live cells. These labeled loci are identified, counted and tracked automatically using custom MATLAB software which enables the analysis of a large number of nucleoid conformations. Positions of the labeled loci are determined with respect to the cell body and used to compute both the distribution of locations of single loci within the cell (thus revealing “chromosome territories”) as well as the correlations between fluctuations in the positioning of different loci. This data is analyzed in the context of a simple polymer model of the E.coli chromosome and it provides quantitative support for a nucleoid-centered mechanism of chromosome organization.
Benefits and Risks of Reverse Inclusion for Preschoolers with and without Disabilities: Perspectives of Parents and Providers

This study compares perspectives about benefits and risks of inclusion of 237 parents of children with and without disabilities and 118 providers in the same community-based reverse inclusion preschool program, using the same measures. Confirmatory factor analyses revealed a two-factor structure, risks and benefits, based on scale scores from the study samples. Providers and parents strongly agreed that inclusion was beneficial for both preschoolers with and without disabilities. Parents' perspectives about potential risks for both groups of children were greater than providers' perspectives. Providers and parents reported greater support for including children with mild and moderate disabilities than children with severe disabilities. Attitudes toward inclusion among providers were not associated with years of experience. Implications for practice and research are discussed.
Contribution of Akt and endothelial nitric oxide synthase to diazoxide-induced late preconditioning.

The opening of mitochondrial ATP-sensitive K+ (mitoKATP) channels has a significant role in delayed ischemic preconditioning, and nitric oxide (NO) is a well-known trigger for its activation. Howev...
An application of maximal dissipative sets in control theory

Abstract A model of a distributed-boundary control system is considered. Assume the uncontrolled system possesses an exponential asymptotically stable zero solution. We then construct suboptimal feedback controls for the distributed and boundary control problems via the direct method of Liapunov. Furthermore, existence-uniqueness of the synthesized control systems is proven by applying the theory of nonlinear semigroups and maximal dissipative sets. Applications to diffusion equations are given.
Penile sensitivity in men: a composite of recent findings

Abstract Objectives. To present, in standardized form, age- and dysfunction-related data from 13 studies on vibrotactile penile epiglandal thresholds in men to allow cross-study comparisons, a capability previously prevented by the use of varying methods and units of measurement. Methods. On the basis of the summarization and standardization of multiple studies located through online searches of bibliographic data bases, penile sensory thresholds were first plotted as a function of age, and then as a function of dysfunctional or disease status. In a third plot, both age- and dysfunction-related differences were illustrated within a single plot. Results. An increasing curvilinear threshold as a function of age was confirmed in the pattern derived from multiple studies. Furthermore, even when controlling for age, penile thresholds of men with erectile dysfunction lay one or more standard deviations above those of sexually functional counterparts, and this deviation became even higher during penile tumescence. When relationships among age, dysfunctional/disease status, and penile threshold were examined simultaneously, potential compounding effects of age and dysfunction emerged. Conclusions. From a research perspective, standardized information on penile vibrotactile thresholds will facilitate ongoing study aimed at elucidating the role of penile sensitivity to both erectile and ejaculatory response. From a clinical perspective, standardized information on populations of sexually functional and dysfunctional men may assist in a preliminary differential diagnosis.