cssi/SciSciGPT-SciSciNet huggingface dataset:
Modification of platelet function and arachidonic acid metabolism by bioflavonoids: Structure-activity relations

The mechanism of the antiaggregating activity of flavonoids was studied in vitro. The activity of fifteen different compounds was tested on platelet aggregation and arachidonic acid metabolism. The effect of flavonoids on platelet adenosine 3',5'-cyclic monophosphate (cyclic AMP) levels under basal conditions, as well as after stimulation by prostacyclin (PGI2), was also measured. The glycons of flavonoids in general and the flavanone derivatives that we tested did not affect platelet function. On the other hand, flavone, chrysin , apigenin and phloretin inhibited platelet aggregation by depressing the cyclooxygenase pathway. In addition, flavone, chrysin and apigenin reduced the platelet cyclic AMP response to PGI2. This effect was probably mediated by an inhibition of adenylate cyclase. Myricetin and quercetin, however, increased the PGI2-stimulated rise of platelet cyclic AMP. Both of these flavonoids inhibited primarily lipoxygenase activity. Modification of platelet cyclic AMP metabolism through inhibition of phosphodiesterase activity was found to be the probable mechanism of their antiaggregating effect.
Domain Wall Solutions

Of the large variety of topological defects that are known, domain walls are the simplest to understand in many ways. The underlying topology that gives rise to domain walls is discrete and can easily be visualized. In some models the equations of motion can be solved analytically leading to explicit expressions. Since the topology is discrete, formation via the Kibble mechanism can be discussed in terms of known results in percolation theory. Hence it is instructive to embark on a study of topological defects starting with the simplest case of domain walls. The purpose of these lectures is to get you started.
Epigenetic mechanisms in diurnal cycles of metabolism and neurodevelopment

The circadian cycle is a genetically encoded clock that drives cellular rhythms of transcription, translation and metabolism. The circadian clock interacts with the diurnal environment that also drives transcription and metabolism during light/dark, sleep/wake, hot/cold and feast/fast daily and seasonal cycles. Epigenetic regulation provides a mechanism for cells to integrate genetic programs with environmental signals in order produce an adaptive and consistent output. Recent studies have revealed that DNA methylation is one epigenetic mechanism that entrains the circadian clock to a diurnal environment. We also review recent circadian findings in the epigenetic neurodevelopmental disorders Prader-Willi, Angelman and Rett syndromes and hypothesize a link between optimal brain development and intact synchrony between circadian and diurnal rhythms.
Production of Staphylococcal Alpha Toxin I. Relationship Between Cell Growth and Toxin Formation

Alpha toxin production and its relationship to cell growth were studied in the Wood 46 strain of Staphylococcus aureus. Toxin first appeared in the culture in the late logarithmic stage, but at least 80% was produced during the subsequent period of slower cell growth. The toxin concentration per unit of cell mass or viable count increased continually throughout the period of toxin production and and at its maximum represented 1.6 to 2.0% of the dry weight of the cells. The possibility that alpha toxin is released as a result of cell lysis was examined by using the appearance of cellular deoxyribonucleic acid in the medium as an indicator of lysis. The results showed that no appreciable amount of lysis occurred during toxin production; at a time when almost maximum amounts of toxin were present in the culture, less than% 4 of the cells had lysed. This finding, together with the observation that less than 0.25% of the total amount of toxin in the culture could be found intracellularly, indicates that alpha toxin is released from intact cells shortly after it is synthesized.
Thrombospondin-1 (TSP1) Contributes to the Development of Vascular Inflammation by Regulating Monocytic Cell Motility in Mouse Models of Abdominal Aortic Aneurysm

Rationale:Histological examination of abdominal aortic aneurysm (AAA) tissues demonstrates extracellular matrix destruction and infiltration of inflammatory cells. Previous work with mouse models of AAA has shown that anti-inflammatory strategies can effectively attenuate aneurysm formation. Thrombospondin-1 is a matricellular protein involved in the maintenance of vascular structure and homeostasis through the regulation of biological functions, such as cell proliferation, apoptosis, and adhesion. Expression levels of thrombospondin-1 correlate with vascular disease conditions. Objective:To use thrombospondin-1–deficient (Thbs1−/−) mice to test the hypothesis that thrombospondin-1 contributes to pathogenesis of AAAs. Methods and Results:Mouse experimental AAA was induced through perivascular treatment with calcium phosphate, intraluminal perfusion with porcine elastase, or systemic administration of angiotensin II. Induction of AAA increased thrombospondin-1 expression in aortas of C57BL/6 or apoE−/− mic...
A toothpick inoculation method for evaluating carrot cultivars for resistance to Alternaria radicina.

Additional index words. black rot, postharvest disease, Daucus carota, disease resistance Abstract. The susceptibility of 46 carrot cultivars to infection by Alternaria radicina Meier, Drechsler, and Eddy, causal agent of black rot disease, was evaluated in field trials with a toothpick inoculation method. Toothpicks infested with A. radicina were inserted into the shoulders of 10- to 12-week-old carrots ( Daucus carota L.) and lesion areas were measured 9 to 10 weeks later. There were significant differences in lesion size among cultivars. Relatively resistant cultivars included 'Panther' and 'Caro-pak', and suscep- tible cultivars included 'Royal Chantenay' and 'Nogales'. Nine of the cultivars were inoculated with A. radicina-infested toothpicks and maintained in cold-storage for 10 weeks. Lesion development was greater in cold-storage than in the field, but the relative ranking of cultivars in terms of resistance to A. radicina was similar.
State estimation in high-mix semiconductor manufacturing

Abstract The traditional way of state estimation in semiconductor manufacturing, known as “threaded” state estimation, segregates the process data into different bins and uses the ones that match the current event of the specific context information (such as tools, layers, products) to update the process state. The limitation of threaded state estimation is that a narrowly defined process stream can result in too many different threads and insufficient data for each thread. This limitation becomes more severe in high-mix manufacturing, where there can be many products and many tools. Hence there is great interest in estimation methods that utilize all available data in the analysis. In this work, the characteristics inherent in state estimation of high-mix semiconductor manufacturing processes are analyzed, and a general framework is introduced for the non-threaded state estimation methods, i.e., state estimation without segregating the process data into different bins. The framework is based on the best linear unbiased estimate (BLUE) of a simplified stationary singular Gauss–Markov process, and non-threaded state estimation methods based on the Kalman filter, least squares and recursive least squares (RLS) are analyzed using the general framework. Simulation examples are presented to illustrate the equivalence between different algorithms. As real processes are rarely stationary, modifications to the Kalman filter and RLS are discussed. We show that in non-threaded state estimation, how to regulate the estimate covariance plays a significant role in estimation performance. To handle nonstationary disturbances that often occur in semiconductor processes, Bayesian-enhanced adaptive versions of the Kalman filter and RLS are proposed. Both simulated and industrial nonstationary processes are used to demonstrate the effectiveness of the proposed adaptive methods.
Diurnal oscillations in pineal melatonin content.

Abstract Using a quantitative bioassay technique, a cyclic variation in pineal melatonin content was monitored in laboratory rats and two species of birds. The oscillation was found to bear a consistent phase relationship to that of cyclic changes in environmental illumination. In each instance, the level of pineal melatonin content in the dark phase of the lighting cycle was several times higher than that in the light phase.
Racial Conflict and Political Choice A Study of Mayoral Voting Behavior in Los Angeles and New York

This article proposes a theoretical framework for the study of local voting behavior. The central argument is that salient group interests often act as political cues in local elections. The extent to which group interests influence electoral outcomes and overshadow other more traditional political cues, such as partisanship, is fundamentally related to the political context and the degree of group conflict. Analyzing public opinion surveys from three mayoral elections-New York (1989), New York (1993), and Los Angeles (1993)—this study finds that heightened levels of group conflict correspond with racially motivated voting in all three cases.
The effects of decreased aeration on the electron transport system and glyconeogenesis during growth of Tetrahymena pyriformis

1. 1. During growth of Tetrahymena pyriformis there is a gradual decline of oxygen consumption and ATP synthesis by the cells. 2. 2. Spectral determination of the mitochondrial cytochromes indicates an increase in cytochromes b and c and a decrease in cytochrome oxidase associated with the respiratory and energy changes. 3. 3. Glyconeogenesis, an important metabolic function in Tetrahymena, is most active during oxygen limitation and diminished respiration. 4. 4. These observations suggest, though do not prove, a possible regulation of glyconeogenests in Tetrahymena at the level of electron transport.
Systemic and Targeted Therapy for Biliary Tract Tumors and Primary Liver Tumors

Tumors of the biliary tract and hepatocellular carcinoma (HCC) are complex tumors with heterogeneous carcinogenic mechanisms. Patients with hepatobiliary cancer have advances disease and need systematic therapy to palliate symptoms and extend survival. Development of effective systematic therapy is a significant unmet medical need. It is hoped that current and future clinical trials will identify additional effective systemic agents, combination systemic therapies, and combined modality options. The HCC community needs validated biomarkers to help identify the patients who will benefit most from emerging treatment options.
Optimal scheduling of examinations for the early detection of disease

SUMMARY The general theory of scheduling examinations for the diagnosis of disease is formulated with respect to the optimal spacing between examinations. This same theory is also applicable, with a change in language, to the inspection of equipment and the scheduling of patients under surveillance with disease. Optimal scheduling programmes are investigated using a weighted utility function which is linear in the probabilities both of finding a case at examination and of being clinically incident between examinations. If disease incidence is independent of time, then a necessary and sufficient condition for the intervals to be equally spaced is that the sensitivity of the examination be unity. The equations for finding the optimal intervals are derived and depend on the distribution of the pre-clinical sojourn times and the sensitivity of the test. If the sojourn distribution is exponential, the optimal intervals are equal except for the first and last intervals.
Over 50 and ready to shop: serving the aging consumer

Purpose – The purpose of this paper is to provide a framework to better understand the emerging aging consumer markets. It identifies new principles to better serve the ranks of the 50+ consumer market as those segments grow in number and economic influence.Design/methodology/approach – The framework was developed following industry and literature reviews and analysis of secondary data from the Social Security Administration, Census Bureau, US Department of Labor, UN Population Division, and AARP.Findings – Demographics point to a significant rise in the importance and complexity of consumer markets in the age 50+ segments. There are psychological, social, economic and biological changes that affect the spending habits and priorities of these consumers and, while there are excellent examples of companies taking these factors into account in designing products and services, it is clear that we have only begun to consider how best to serve aging and generally affluent consumers.Practical implications – The ...
Automated cloud and shadow detection and filling using two-date Landsat imagery in the USA

A simple, efficient, and practical approach for detecting cloud and shadow areas in satellite imagery and restoring them with clean pixel values has been developed. Cloud and shadow areas are detected using spectral information from the blue, shortwave infrared, and thermal infrared bands of Landsat Thematic Mapper or Enhanced Thematic Mapper Plus imagery from two dates a target image and a reference image. These detected cloud and shadow areas are further refined using an integration process and a false shadow removal process according to the geometric relationship between cloud and shadow. Cloud and shadow filling is based on the concept of the Spectral Similarity Group SSG, which uses the reference image to find similar alternative pixels in the target image to serve as replacement values for restored areas. Pixels are considered to belong to one SSG if the pixel values from Landsat bands 3, 4, and 5 in the reference image are within the same spectral ranges. This new approach was applied to five Landsat path/rows across different landscapes and seasons with various types of cloud patterns. Results show that almost all of the clouds were captured with minimal commission errors, and shadows were detected reasonably well. Among five test scenes, the lowest producer's accuracy of cloud detection was 93.9% and the lowest user's accuracy was 89%. The overall cloud and shadow detection accuracy ranged from 83.6% to 99.3%. The pixel-filling approach resulted in a new cloud-free image that appears seamless and spatially continuous despite differences in phenology between the target and reference images. Our methods offer a straightforward and robust approach for preparing images for the new 2011 National Land Cover Database production.
ON THE SYNTHESIS OF ReF7 AND THE EXISTENCE OF ReF2 AND ReF3.

The metal explosion technique can be used to synthesize a number of rhenium fluorides, including several that have not been reported previously. Under certain reaction conditions, one can obtain mixtures of the volatile fluorides ReF7 and ReF6. Under other conditions, one can prepare ReF7 free of ReF6. These volatile fluorides are products of Re-SF6 reactions. They are accompanied by the formation of non-volatile rhenium fluoride films, which are soluble in aqueous NaOH solutions. A rhenium trifluoride is formed at high levels of imparted electrical energy, whereas a tetrafluoride forms at low energy levels. Rhenium explosions in PF5 produced a rhenium difluoride, which is also readily soluble in aqueous NaOH solutions. For this reason the difluoride can be readily separated from unreacted Re powder with which it is admixed on the reactor wall. The difluoride can also be scraped from the reactor wall, but the ReF2 recovered in this way is admixed with a much larger quantity of unreacted metal powder.
Recursive Elements and Constructive Extensions of Computable Local Integral Domains

With reservations, one can think of abstract algebra as the study of what consequences can be drawn from the axioms associated with certain concrete algebraic structures. Two important examples of such concrete algebraic structures are the integers and the rational numbers. The integers and the rational numbers have two properties which are not in general mirrored in the abstract axiom systems associated with them. That is, the integers and the rational numbers both have effectively computable metrics and their algebraic operations are effectively computable. The study of abstract algebraic systems which possess effectively computable algebraic operations has produced many interesting results. One can think of a computable algebraic structure as one whose elements have been labeled by the set of positive integers and whose operations are effectively computable. The formal definition of computable local integral domain will be given in §3. Some specific computable structures which have been studied are the integers, the rational numbers, and the rational numbers with p-adic valuation. Computable structures were studied in general by Rabin [12]. This paper concerns computable local integral domains as exemplified by the local integral domain Zp. Zp is the localization of the integers with respect to the maximal prime ideal generated by the positive prime p. We should note that the concept of local integral domain is not first order.Let the ordered pair (Q, M) stand for a local ring, where Q is the local ring and M is the unique maximal prime ideal of Q. Since most of my results are proving the existence of certain effective procedures, the assumption that Q has a principal maximal ideal M (rather than M has n generators) greatly simplifies many of the proofs.
Mechanism for resveratrol-induced cardioprotection against reperfusion injury involves glycogen synthase kinase 3β and mitochondrial permeability transition pore

Resveratrol pretreatment can protect the heart by inducing pharmacological preconditioning. Whether resveratrol protects the heart when applied at reperfusion remains unknown. We examined the effect of resveratrol on myocardial infarct size when given at reperfusion and investigated the mechanism underlying the effect. Isolated rat hearts were subjected to 30 min ischemia followed by 2 h of reperfusion, and myocardial samples were collected from the risk zone for Western blot analysis. Mitochondrial swelling was spectrophotometrically measured as a decrease in absorbance at 520 nm (A520). Resveratrol reduced infarct size and prevented cardiac mitochondrial swelling. Resveratrol enhanced GSK-3β phosphorylation upon reperfusion, an effect that was mediated by the cyclic guanosine monophosphate (cGMP)/protein kinase G (PKG) pathway. Resveratrol translocated GSK-3β from cytosol to mitochondria via the cGMP/PKG pathway. Further studies showed that mitochondrial GSK-3β was co-immunoprecipitated with cyclophilin D but not with VDAC (voltage dependent anion channel) or ANT (adenine nucleotide translocator). These data suggest that resveratrol prevents myocardial reperfusion injury presumably by targeting the mPTP through translocation of GSK-3β from cytosol to mitochondria. Translocated GSK-3β may ultimately interact with cyclophilin D to modulate the mPTP opening.
Numerical simulation of hydrogen dispersion in the vicinity of a cubical building in stable stratified atmospheres

Abstract A computational fluid dynamics (CFD) approach using the standard k - e turbulence model was applied to simulate hydrogen and methane dispersion around a cubical building. Model results were compared against towing-tank data and other numerical results. The relative impact between hydrogen and methane releases on the building and its surroundings under several stable atmospheric stratifications was assessed. The computed dispersion patterns show a greater risk potential of hydrogen in comparison to methane when released in the vicinity of a building. However, since hydrogen rapidly rises, the impact of a release on the surrounding buildings promptly diminishes. The results also depict complex interactions of hydrogen dispersion patterns due to strong buoyant forces.
Quantitation of high density lipoproteins

The demand for high density lipoprotein (HDL) quantitation has dramatically increased with the renewed awareness of the importance of HDL as a negative risk factor for coronary heart disease. HDL is usually estimated by specific precipitation of the non-HDL apoB-containing lipoproteins by polyanions and divalent cations followed by measurement of cholesterol in the supernatant. A common procedure involves precipitation with sodium heparin at 1.3 mg/ml and MnCl2 at 0.046 M (final concentrations). This method is appropriate for serum but less than ideal for plasma because of incomplete precipitation and sedimentation of the apoB-containing lipoproteins. A two-fold increase in Mn2+ to 0.096 M improves precipitation of the apoB-associated lipoproteins from plasma without excessive precipitation of HDL. This modified heparin-Mn2+ procedure gives results nearly identical to the results with the ultracentrifugal reference method (cholesterol in the d>1.063 fraction corrected for losses and the presence of apoB-associated cholesterol). The dextran sulfate 500-Mg2+ and the sodium phosphotungstate-Mg2+ procedures give results consistently 2–4 mg/dl lower than does the reference method. In contrast, a heparin-Ca2+ method gives results 5–8 mg/dl higher than does the reference method. Immunochemical analysis of apoA-I in the precipitate and apoB in the supernatant indicates that lower values for the phosphotungstate-Mg2+ procedure is due to partial precipitation of the A-I-containing lipoproteins, while higher values by the heparin-Ca2+ method are due to incomplete precipitation of the apoB-containing lipoproteins. Quantitation of the principal apoproteins of HDL, A-I and A-II, represent an important additional index of HDL concentrations and composition. Quantitation of plasma A-I and A-II concentrations by radial immunodiffusion indicates that women generally have higher HDL concentrations than men (women, A-I, 135±25, A-II, 36±6; men, A-I, 120±20, A-II, 33±5; mean±S.D., in mg/dl). A-I and A-II do not increase with age in men but show a slight increase with age in women. Estrogen increases HDL cholesterol and protein and may in part account for the higher HDL in women. The lighter density HDL subclass has a higher A-I/A-II ratio than the denser HDL subclass, with women generally having significantly more of the lighter HDL subclass. Density-gradient ultracentrifugation in CsCl2 gradients indicates that HDL contains subpopulations of differing hydrated density which vary in the A-I/A=II ratio. Immunoassay of A-I and A-II when used in combination with HDL cholesterol analysis is a powerful tool for studies of HDL structure, epidemiology and metabolism.
Gas filtration in granular moving beds — an experimental study

An experimental study was conducted of gas filtration in cross-flow moving-bed granular filters. Variables examined included both the gas and solid velocities as well as filter-grain size. The triboelectric effect was found to play an important role in determining the extent of particle collection. On a mene une etude experimentale sur la filtration du gaz dans des filtres granulaires en lit mobile et en ecoulement croise. Les variables etudiees comprennent les vitesses de gaz et de solides ainsi que la taille des pores de filtres. On montre que l'effet triboelectrique exerce un role preponderant pour evaluer l'importance de la recuperation.
Zinc transporter found attached to n‐methyl‐d‐aspartate receptors

This editorial highlights a study by Mellone et al. (2014) entitled “Zinc transporter-1 (ZNT-1): a novel NMDA receptor binding protein at the postsynaptic density” in this issue of Journal of Neurochemistry, which reports for the first time that the zinc-transporter ZnT1 interacts directly and in an activity-dependent manner with the cytoplasmic tail of the zinc-sensitive N-methyl-D-aspartate (NMDA) receptors. The highlighted article suggests a novel pathway towards ion homeostasis through balancing zinc and calcium ions (Zn2+ and Ca2+) and involving receptor modulation at synapses.
Reading Comprehension: Effects of Individualized, Integrated Language Arts as a Reading Approach with Struggling Readers

This study examined the effects of individualized, integrated language arts as a reading approach on struggling readers' comprehension scores obtained from oral narrative, silent narrative, and silent expository passages at three levels: below-grade, on-grade, and above-grade levels. Students (N = 93) in grades four through eight, who were reading below grade level, participated in the study. Treatment group students (n = 51) received individualized, integrated language arts as a reading approach once a week in place of basal reading instruction. Comparison group students (n = 42) received basal reading instruction for the duration of the study. Multivariate analysis of covariance was used to analyze posttest Analytical Reading Inventory (ARI) comprehension scores. Several statistically significant (p < .001) differences in comprehension performance were found for on-grade-level scores and for above-grade-level scores, but few differences were found between treatment and comparison groups on below-grade-l...
Extended Test Time and postsecondary Students with Learning Disabilities: A Model for Decision Making

The most frequently requested accommodation among students with learning disabilities (LD) in postsecondary settings is extended test time. The frequency with which this accommodation is requested and granted compels disability service providers to become knowledgeable about the factors that influence the need for, and appropriateness of, the accommodation. Moreover, the synthesis of these factors becomes the basis for determining if the accommodation is reasonable under federal law. The purpose of this article is to present a step-by-step model to be used as a decision-making process when considering the accommodation of extended test time for postsecondary students with LD. The model is designed to assist disability service providers in the analysis and synthesis of information collected from (1) the student's diagnostic evaluation, (2) the course or classroom test to be accommodated, and (3) student interviews. A list of diagnostic tests from the four most frequently administered test batteries used with adults is provided, along with a concise explanation of how characteristics of LD impact reading, writing, and math, and relate to the need for extended time. This information can be used to determine if extended test time is a reasonable accommodation and to estimate how much additional time to provide.
Unified picture for spin-lattice relaxation of lipid bilayers and biomembranes

The present study compares and interprets the 1H, 2H, and 13C spin‐lattice (T1) relaxation times of 1,2‐dipalmitoyl‐sn‐glycero‐3‐phosphocholine (DPPC), in the liquid crystalline phase, in terms of models for the molecular dynamics of lipid bilayers. The 1H T1 times of the DPPC bilayer hydrocarbon region at two frequencies and 13C T1 data at seven frequencies, for which the relaxation is dipolar in origin, as well as the 2H T1 data at three frequencies, due to the quadrupolar interaction, can be unified and interpreted in terms of a collective model for order fluctuations. In normalizing the 13C T1 data to the 1H and 2H T1 values, a vibrationally corrected 13C–1H distance parameter of r0CH=1.14 A has been assumed, rather than the equilibrium bond length of 1.09 A. The analysis suggests that the behavior of the individual acyl chain segments of lipid bilayers, in the liquid crystalline phase, is similar to that of molecules in nematic fluids.
Production scheduling on parallel machines: a case study

This case study reports the development and implementation process of a production planning system for a carbon products manufacturer. The model developed for the company provides an optimal production sequence by minimizing the setup costs. Initially, the optimal sequence obtained faced hurdles at the implementation stage due to : (i) lack of integration of information systems among different corporate units, and (ii) the insensitivity of the traditional productivity measurement standards which do not account for the costs of quality but over-emphasize the capacity utilization instead. Such hurdles were overcome by addressing performance measurement issues and information systems integration. The integration of information in a timely fashion turned out to be a major factor in successfully implementing the system.
Multi-quasiparticle induced prolate-oblate transitions in rapidly rotating N = 88,90 nuclei

Abstract Calculations have been performed to explain in a uniform way three recently measured phenomena in the N = 88–90 region: the quenching of signature-splitting in π h 11 2 bands, the reduction of E2 transition rates after the first backbend, and the loss of collective band structure in the I = 30–40 ℏ range. The model incorporates the tendency of high-j quasiparticles to drive the nucleus to triaxial shapes.
Computation of semi-infinite integrals on a programmable hand calculator

Abstract Two functions arising in physical applications which are defined by complicated integral expressions are evaluated on a programmable hand calculator. The method is based on a quadrature rule using nodes in a geometric progression. This rule is particularly suitable for use on a hand calculator because the weights and nodes are easily generated during the calculations.
Possible formation of meteoritic chondrules and inclusions in the precollapse Jovian protoplanetary atmosphere

Abstract Most meteoritic chondrules and inclusions appear to have been liquid droplets at one time, or at least to have been close to the melting point so that they are easily deformed. The simplest mode of formation of such objects would be to have the liquid phases of the chondrules in thermodynamic equilibrium with gas in the primitive solar nebula, as suggested some years ago by Wood, but unfortunately pressures in the primitive solar nebula are orders of magnitude too small at temperatures in the range of the liquid mineral phases. This difficulty has led to an abandonment of this basic idea, but we suggest that the idea should be reexamined in view of the presence of higher pressures at moderate temperatures, together with water vapor enrichments, in the protoplanetary atmosphere of Jupiter prior to the collapse stage, which was recently studied by Perri and Cameron. A number of advantages arise from the complexities of such a model, and we discuss these together with a number of constraints.
Fenton Reagents (1:1 FeIILx/HOOH) React Via [LxFeIIOOH(BH+), 1] as Hydroxylases (RH → ROH); NOT as Generators of Free Hydroxyl Radicals (HO·)

The one-to-one combination of hydrogen peroxide and FeII(PA)2 [PAH = picolinic acid (2-carboxyl-pyridine)], a Fenton reagent, forms an adduct \( \{ {\text{F}}{{\text{e}}^{{\text{II}}}}{({\text{PA}})_2} + {\text{HOOH}}\xrightarrow[{{{({\text{py}})}_2}{\text{HOAc}}}]{{{\text{k}},{\text{2}} \times {\text{1}}{{\text{0}}^3}{{\text{M}}^{ - 1}}{{\text{s}}^{ - 1}}}}[{({\text{PA}})_2}^ - {\text{F}}{{\text{e}}^{{\text{II}}}}{\text{OOH}} + {\text{py}}{{\text{H}}^ + }](1)\} \) that is (py)2HOAc the primary reactant with (a) excess FeII(PA)2 to give two (PA)2FeIIIOH, (b) excess HOOH to give O2 plus two H2O, and (c) excess cyclohexane (C-C6H12) to give (c-C6H11)py (or c-C6H11OH in the absence of pyridine). The presence of a carbon-radical trap (PhSeSePh) with the organic substrate yields c-C6H11SePh with an efficiency of >90% (relative to HOOH). This Fenton reagent has reactivity ratios (kA/kB) [in comparison with free HO·] with c-C6H12/c-C6D12 (KIE) of 1.7 [versus 1.0], with l°/2°/3° carbon centers (per C-H, normalized) of 0.07/0.44/1.0 [0.41/0.50/1.0], and with c-C6H12/PhCH2CH3 of 2.0 [0.6]. In the presence of O2 (1 atm, 3.4 mM) 1 forms an adduct [1(O2), 5], which reacts with c-C6H12 to give c-C6H10(O) (KIE, 2.1), cyclohexene (c-C6H10) to give c-C6H8(O), and PhCH2CH3 to give PhC(O)CH3 (reactivity ratio for c-C6H12/PhCH2CH3, 0.6). Similar chemistry results for HOOH/O2 with FeII(bpy)22+ [reactivity ratio for c-C6H12/PhCH2CH3 (0.4)], FeII(OPPh3)42+ (1.0), and CuI(bpy) 2 + (1.0)]. All of this is compelling evidence that Fenton reagents do not produce (a) free hydroxyl radicals (HO·) or (b) free carbon radicals (R·), but (c) can exhibit catalytic turnovers with respect to HOOH and O2.
On-the-fly fluorescence lifetime detection of labeled DNA primers

The first application of frequency-domain, on-the-fly fluorescence lifetime detection to the detection, identification and resolution of fluorescent labeled oligonucleotide primers in capillary electrophoresis is presented. These studies, which are directed towards the development of four-decay DNA sequencing, employed two common sequencing primers, SP6 and M13/pUC. The primers were each tagged by a derivative of either fluorescein or BODIPY. Fluorescence emission maxima and lifetimes of the free dyes and the labeled primers were determined both in batch mode and on-the-fly in capillary electrophoresis. Fluorescence intensity and lifetime electropherograms were extracted from dynamic lifetime data that were acquired at 0.1-s intervals during the CE separation. Lifetimes were recovered using either conventional non-linear least-squares analysis or the self-modeling maximum entropy method, which does not require prior knowledge of the system. Based on migration time and fluorescence lifetime, peaks could be detected and identified, and co-eluting peaks could be resolved. Interference from background impurities and scattered light was greatly reduced by the combination of physical separation and lifetime resolution.
Variation in symbiont uptake in the early ontogeny of the upside-down jellyfish, Cassiopea spp.

The upside-down jellyfish Cassiopea, like many cnidarians, form obligate symbioses with dinoflagellates belonging to the genus Symbiodinium (commonly known as zooxanthellae). In adult Cassiopea, the symbiosis is specific, with a given Cassiopea species hosting a particular symbiont phylotype throughout broad distributions. However multiple phylotypes of Symbiodinium can infect the scyphistoma (polyp) stage of development, making Cassiopea spp. an ideal model to study the effects of symbiont phylotype on host development and proliferation. To assess the flexibility of symbiont acquisition and to understand how symbiont identity affects the early stages of Cassiopea development, symbiont uptake and host developmental traits were monitored in two species of Cassiopea that were exposed to multiple symbiont phylotype in laboratory and field experiments. Scyphistomae of Cassiopea ornata and Cassiopea xamachana both demonstrated flexibility in their symbiosis at the scyphistoma stage during which they acquired a range of laboratory cultured Symbiodinium. The presence of symbionts in C. ornata increased planuloid production relative to uninfected controls, and the rate at which symbionts accumulated in the polyp tissues varied with symbiont phylotype. Laboratory infected C. xamachana polyps continued to take up novel/additional symbiont types when transferred to the field; however, novel uptake occurred significantly less frequently in polyps that harbored homologous (ITS type-A1) symbionts prior to field placement. Similarly, ephyrae of C. ornata were able to acquire additional symbiont types even when already infected with Symbiodinium ITS type C1. Our findings demonstrate that the symbiosis is flexible within the early ontogeny of Cassiopea, but that associating with the “right” symbiont may provide a developmental advantage for that host.
Effect of insulin on the distribution of cardiac output in the fetal lamb.

ABSTRACT. Three to five measurements of fetal cardiac output and its distribution were made using radiolabeled microspheres in each of 12 sheep fetuses in whom fetal plasma insulin concentration was varied by exogenous infusion of insulin to the fetus. Blood concentrations of oxygen and glucose as well as blood gases, pH, hematocrit, and plasma insulin concentrations were also measured. Both fetal arterial oxygen content and whole blood glucose concentration fell as fetal insulin concentration rose. Fetal cardiac output rose as insulin concentration increased and was accompanied by an increase in fetal heart rate. Increased insulin concentration was associated with increased flow to the heart, stomach, placenta, and carcass while blood flow to the fetal brain, lungs, liver, kidneys, spleen, and intestines was not affected. As plasma insulin concentration rose, the percentage of the cardiac output distributed to the fetal heart and upper carcass increased; that distributed to the fetal brain, lungs, liver, stomach, intestines, and lower carcass remained unchanged; while that distributed to the kidneys, spleen, and placenta decreased. When expressed as a fraction of cardiac output, an additional 7% (from 39 to 46%) of the cardiac output was distributed to carcass over the range of insulin concentrations studied. Most of the increased portion of the fetal cardiac output distributed to the fetal carcass during hyperinsulinemia was accounted for by a decrease in the percentage of fetal cardiac output perfusing the placenta.
ORIENTATIONAL ISOMERS AND MONOLAYER STRUCTURE OF CH3D PHYSISORBED ON NACL(100)

Polarized infrared spectra of CH3D adsorbed on NaCl(100) in the temperature range 5−37 K are reported. Analysis of the ν2 spectral region reveals one transition dipole perpendicular to the surface and two oriented at 70 ± 20° (or 110 ± 20°) from the surface normal. These features are assigned to C−D stretching vibrations of molecules oriented in a tripod conformation with the deuterium in the “top” position (D-up) and in a tripod with the deuterium in a “base” position (D-down). The fraction of D-up orientational isomers is shown to decrease with decreasing temperature. An energy splitting of 100 ± 20 J mol-1 between D-up and D-down orientational isomers is consistent with this temperature dependence. A phase transition near 30 K associated with changes in rotatory motions has been observed. Below this transition, a splitting in the D-down region is shown to be statistically consistent with the position of the deuterium atoms on the surface. Some point toward substrate chloride ions and others point towar...
Analysis of participation in an online photo-sharing community: A multidimensional perspective

In recent years we have witnessed a significant growth of social-computing communities—online services in which users share information in various forms. As content contributions from participants are critical to the viability of these communities, it is important to understand what drives users to participate and share information with others in such settings. We extend previous literature on user contribution by studying the factors that are associated with various forms of participation in a large online photo-sharing community. Using survey and system data, we examine four different forms of participation and consider the differences between these forms. We build on theories of motivation to examine the relationship between users' participation and their motivations with respect to their tenure in the community. Amongst our findings, we identify individual motivations (both extrinsic and intrinsic) that underpin user participation, and their effects on different forms of information sharing; we show that tenure in the community does affect participation, but that this effect depends on the type of participation activity. Finally, we demonstrate that tenure in the community has a weak moderating effect on a number of motivations with regard to their effect on participation. Directions for future research, as well as implications for theory and practice, are discussed. © 2010 Wiley Periodicals, Inc.
Relative Potencies of Different Cytochalasins for the Inhibition of Phagocytosis in Ciliates

Ciliate actins have been reported to exhibit an unusual degree of sequence divergence, within the phylum Ciliophora, and when compared to actins from other organisms. To determine whether these primary structural differences are correlated with pharmacological differences, we investigated the effects of seven cytochalasins on phagocytosis, which has been shown to be actin-dependent in eukaryotic cells. The relative potencies of cytochalasin inhibition of phagocytosis in Spirostomun ambiguum and Paramecium multimicronucleatum were similar. Dihydrocytochalasin B and cytochalasin A were the most potent of the seven cytochalasins in both ciliates, and strongly inhibited phagocytosis at 20-40 μM. Dihydrocytochalasin B was considerably more potent than either cytochalasins B or D, a result unexpected on the basis of reports utilizing other organisms. However, even at concentrations up to 100 μM, dihydrocytochalasin B did not inhibit the rate of Spirostomum defecation. After long-term treatment of Spirostomum with 50 μM dihydrocytochalasin B, the sensitivity of phagocytosis to the drug was reduced. These results indicate that the relative cytochalasin sensitivities of actin-dependent functions in ciliates differ from those of other organisms, and are consistent with the hypothesis that sequence differences might give rise to substantial differences in the pharmacological properties of ciliate actins.
SU-FF-T-245: Improvement of QA Pass-Rate in IMRT Patient Specific QA Using MapCHECK

Purpose: To demonstrate the improvement in IMRT patient specific quality assurance (QA) by considering a more accurate absolute dose calibration in MapCHECK, machine hardware characteristics and modification in beam modeling in treatment planning system (TPS). Method and Materials: MapCHECK, a 2D diode array system, was used in our routine IMRT patient specific QA on Elekta Synergy S LINAC with Beam Modulator (BM). To explore the absolute dose calibration in MapCHECK, dose at 10 cm water equivalent depth under same reference conditions was calculated for a 6 MV beam for both MapCHECK phantom (CT scanned MapCHECK with 8 cm solid water buildup) and a water phantom (50×50×50 cm3) by Pinnacle TPS, then was compared to each other. 2D dose measurements using film and MapCHECK for 4×4 and 16×16 cm2 were compared with water tank measurements to evaluate the field asymmetry. Results: (1) A 2% systematic difference has been detected in MapCHECK absolute dose calibration. If the QA plan is generated on a solid water phantom rather than on the scanned MapCHECK plus buildup, the pass‐rate can be improved by 1–2%. (2) Accounting for the asymmetric field in superior‐inferior direction associated with beam modulator design, a collimator rotation by 90 degrees in original patient IMRT plans can improve QA pass‐rate by up to 10%. (3) After reducing the source size in Pinnacle TPS beam model to better describe the penumbra, the pass‐rate increased several percent. Comparing QA results before and after implementing steps 1 through 3 in our clinical practice, the pass‐rate increased from 94.7%±2.5%(SD) to 98.6%±2.5%(SD) averaged over 28 patient QAs in each group. Conclusions: By correcting the systematic error in MapCHECK absolute dose calibration, rotating collimator by 90 degrees in patient plans and using a smaller source size in Pinnacle beam model, QA pass‐rate has been significantly improved.
Affinity chromatography with an immobilized RNA enzyme.

Abstract M1 RNA, the catalytic subunit of Escherichia coli RNase P, has been covalently linked at its 3' terminus to agarose beads. Unlike M1 RNA, which is active in solution in the absence of the protein component (C5) of RNase P, the RNA linked to the beads is active only in the presence of C5 protein. Affinity chromatography of crude extracts of E. coli on a column prepared from the beads to which the RNA has been crosslinked results in the purification of C5 protein in a single step. The protein has been purified in this manner from cells that contain a plasmid, pINIIIR20, which includes the gene that codes for C5 protein. A 6-fold amplification of the expression of C5 protein is found in these cells after induction as compared to cells that do not harbor the plasmid.
Mechanism of palladium-catalyzed diene cyclization/hydrosilylation: direct observation of intramolecular carbometalation.

The results of kinetic, deuterium-labeling, and low-temperature NMR studies have established a mechanism for the palladium-catalyzed cyclization/hydrosilylation of dimethyl diallylmalonate (1) with triethylsilane involving rapid, irreversible conversion of the palladium silyl complex [(phen)Pd(SiEt3)(NCAr)]+ [BAr4]- [Ar = 3,5-C6H3(CF3)2] (4b) and 1 to the palladium 5-hexenyl chelate complex {(phen)Pd[η1,η2-CH(CH2SiEt3)CH2C(CO2Me)2CH2CHCH2]}+ [BAr4]- (5), followed by intramolecular carbometalation of 5 to form the palladium cyclopentylmethyl complex [BAr4]- (6), and associative silylation of 6 to release 3 and regenerate 4b.
Improving meson two-point functions in lattice QCD

We describe and test a method to compute Euclidean meson two-point functions in lattice QCD. The contribution from the low-lying eigenmodes of the Dirac operator is averaged over all positions of the quark sources. The contribution from the higher modes is estimated in the traditional way with one or a few source points per lattice. In some channels, we observe a significant improvement in the two-point functions for small quark masses.
Methods in translation science.

Background: The gap between research findings and practice has been, and continues to be, a concern for the international community. A number of descriptive studies have elucidated barriers and facilitators of evidence-based practice in nursing. It is argued that it is now time to use findings from these studies to design and test interventions that explicitly target barriers to the use of evidence in practice rather than doing further research to describe generic barriers and facilitators to evidence-based practice. This article discusses research methods to advance our knowledge regarding the efficacy of translating research into practice (TRIP) interventions that promote and hasten adoption of evidence in practice. Approach: Published research is reviewed and used as exemplars of translation studies. The benefits and challenges in studying natural experiments are addressed as are the benefits and challenges in conducting TRIP studies using experimental designs. Discussion: The article discusses factors such as sample attainment, unit of analysis, intervention characteristics, outcome measurement, and sustainability. Although there are a myriad of initiatives aimed at increasing use of evidence in practice, there is little systematic evidence of the effectiveness of these initiatives. In order to advance knowledge, translation research needs more experimental studies that test TRIP interventions through, for example, partnership models.
Strategies for choosing path-entangled number states for optimal robust quantum-optical metrology in the presence of loss

To acquire the best path-entangled photon Fock states for robust quantum-optical metrology with parity detection, we calculate phase information from a lossy interferometer by using twin entangled Fock states. We show that $(\text{a})$ when loss is less than 50$%$ twin entangled Fock states with large photon number difference give higher visibility, while when loss is higher than 50$%$, the ones with less photon number difference give higher visibility; and $(\text{b})$ twin entangled Fock states with large photon number difference give sub--shot-noise limit sensitivity for phase detection in a lossy environment. This result provides a reference on what particular path-entangled Fock states are useful for real world metrology applications.
Rational compositum genus for a pure cubic field

Abstract In non-Abelian fields, to which genus theory does not ordinarily apply, many of the diophantine by-products are still available. For instance, the representability of primes as norms of principal ideals in different fields of the same degree will bear interrelations if the fields belong to a small compositum as do the four subfields of Q (m ∞ 1/3 , m 0 1/3 ). This is a generalization of a classical phenomenon for quadratic fields. It is particularly effective when just one prime l ≡ 1 (mod 3) divides m 0 m ∞ .