cssi/SciSciGPT-SciSciNet huggingface dataset:
Role of membrane potential and hydrogen bonding in the mechanism of translocation of guanidinium-rich peptides into cells.

The results described herein support a mechanistic hypothesis for how guanidine-rich transporters attached to small cargos (MW ca. 95%) into the octanol layer. In contrast, ornithine oligomers partition almost exclusively into the water layer with and without added sodium laurate. The different partitioning between guanidinium-rich and ammonium-rich oligomers in the presence of sodium laurate is consistent with the ability of the former to form a bidentate hydrogen bonded ion pair. Mono- and dimethylated arginine oligomers, which like ornithine can only efficiently form monodentate hydrogen bonds, were prepar...
Radiotherapy after surgery for benign cerebral meningioma

Abstract Background and purpose To compare the outcome from adjuvant and delayed radiotherapy (RT) after surgery in patients with benign cerebral meningioma. Patients and methods Between March 1953 and January 2001, 92 patients with benign cerebral meningioma (WHO grade I) were treated with surgery. Forty-eight patients underwent gross total resection (GTR), and 44 patients underwent subtotal resection (STR). Treatments were classified as GTR ( n =48), STR+adjuvant RT ( n =12), STR alone ( n =32). The prognostic factors were assessed as, gender, the Karnofsky performance score (KPS) (≥90 vs. Results The median follow-up was 7.7 years. The 5-year PFS and OS rates for all patients were 65 and 93%, respectively. The 5-year PFS rates in patients treated with GTR and STR were 77 and 52%, respectively ( P =0.02). Patients treated with STR+adjuvant RT had significantly better PFS (91%) at 5 years than with STR alone (38%) ( P =0.0005). Gender showed no statistically significant impact on either PFS or OS ( P >0.05). However, multivariate analysis showed the KPS to have a statistically significant effect on OS ( P =0.02). The OS rate was the same across all three treatment groups. The age-adjusted expected survival curve for the US population born in 1970 lay within the confidence intervals for the overall survival curve of the study population. Conclusions Although OS was not affected, adjuvant RT appeared to significantly reduce tumor progression. However, only a prospective randomized trial can adequately determine whether adjuvant or delayed radiotherapy is the better approach in patients with subtotally resected benign meningioma.
A derivative of diethylenetriaminepentaacetic acid for europium labeling of proteins.

Preparation of a reagent that will incorporate diethylenetriaminepentaacetic acid (DTPA) into proteins under mild conditions and make a strong europium chelate is described. Aminoacetaldehyde dieth...
Synthesis and characterization of ortho -3- and meta -2-substituted carboranes through a boron-insertion reaction, including the structure of the product of a double-insertion reaction

Abstract Examples of boron-insertion reactions are presented in which either a functionalized alkene or alcohol is inserted into the open face of a dicarbollide ion. Boron-insertion products of both ortho- and meta-carborane are synthesized, such as closo-3-(3-bromopropyl)-1,2-dicarba-dodecaborane, 6a, and closo-2-(3-bromopropyl)-1,7-dicarbadodecaborane, 6b. While the ortho-3- and meta-2-alkylhydroxy-carborane derivatives, 8a or 8b, respectively, cannot be synthesized directly using this method, they can be prepared first by functionalization of the brominated products, 6a and 6b, to their respective acetate derivatives, 7a and 7b. Then, these acetate derivatives can be reduced to the alcohols, 8a and 8b, respectively. Symmetric or asymmetric double boron-insertion reactions were employed for synthesis of 1,6-bis(closo-1,2-dicarba-3-dodecaboranyl) hexane, 9, and 1,4-bis(closo-1,2-dicarba-3-dodecaboranyl)-1-oxabutane, 11. Both types of boron-insertion products, 4-(closo-1,2-dicarba-3-dodecaboranyl)-4-oxabut-1-ene, 10, and 8a can be selectively degraded by tetrabutylammonium fluoride to form their nido- derivatives, 12 and 13. The X-ray crystal structure of 9 is also presented.
Isolation and characterization of light- and dithiothreitol-modulatable glucose-6-phosphate dehydrogenase from pea chloroplasts

Abstract Glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate: NADP oxidoreductase, EC 1.1.1.49) has been purified to electrophoretic homogeneity from pea chloroplasts. The enzyme, which has a Stokes radius of 52 A, is a tetramer made up of four 56000 Da monomers. The pH optimum is around 8.2. The enzyme is absolutely specific for NADP. The apparent K m (NADP) is 2.4 ± 0.1 μ M. NADPH inhibition of the enzyme is competitive with respect to NADP (mean K i , 18 ± 5 μ M) and is mixed ( K p > K m , V max > V p ) with respect to glucose 6-phosphate (mean crossover point, 0.5 ± 0.1 mM). The apparent K m (glucose 6-phosphate) is 0.37 ± 0.01 mM. The purified enzyme is inactivated in the light in the presence of dilute stroma and washed thylakoids, and by dithiothreitol. Enzyme which has been partially inactivated by treatment with dithiothreitol can be further inactivated in the light in the presence of dilute stroma and washed thylakoids and reactivated in the dark, but only to the extent of the reverse of light inactivation. Dithiothreitol-inactivated enzyme is not reactivated further by addition of crude stroma or oxidized thioredoxin. Dithiothreitol-dependent inactivation of the enzyme follows pseudo-first-order kinetics and shows rate saturation. The enzyme which has been partially inactivated by treatment with dithiothreitol does not differ from the untreated control with respect to thermal and tryptic inactivation. However, enzyme which has been partially light inactivated shows different thermal and tryptic inactivation patterns as compared to the dark control. These observations suggest that the changes in the enzyme brought about by light modulation are not necessarily identical with those brought about by dithiothreitol inactivation.
Detection byin-situ fluorescence of short, single-copy sequences of chromosomal DNA

Short single-copy probes have been widely used in plant molecular biology. However, they have rarely been effective in plant research usingin situ hybridization techniques, possibly due to limitations imposed by the cell wall. We recently developed two fluorescencein situ hybridization protocols for the single-copy sequence detection in soybean. By enzymatically removing the cell wall, single-copy sequences as short as 1 kb were detected by probes using standard fluorescencein situ hybridization or PCR-primedin situ hybridization (PCR-PRINS). Such technology is useful for genome analysis, in plant molecular, cellular, and biotechnological research.
Controlled Test of the Analgesic and Relaxant Properties of Nitrous Oxide

The pain-reducing and calming properties of nitrous oxide mixed with oxygen were evaluated with the use of placebo and standard control groups. Subjects under nitrous oxide had higher pain thresholds and a higher tolerance for shock than placebo and control subjects. They also reported themselves as more relaxed than did placebo and control subjects.
Propagating Order-Parameter Collective Modes in Superconducting Films

A peak at finite frequency has been observed in measurements of the order-parameter dynamical structure factor of short-mean-free-path superconducting aluminum films. The existence of a propagating, low-frequency order-parameter collective mode can be inferred from these results.
What's trending?: mining topical trends in UGC systems with YouTube as a case study

User-generated content (UGC) systems such as Twitter, Face-book, and YouTube are quickly becoming the dominant form of information exchange on the web: shifting informational power from media conglomerates to individual users. Understanding the popularity trends in UGC content has proven problematic as traditional content popularity techniques (e.g. those developed for television) are not suited for the disparate origins and ephemeral lifecycle of UGC. Content-based trend detection with UGC systems has been an intensely growing field of research in recent years, yet surprisingly, there is no single method or approach that can be used to track and compare trends in user posts across multiple UGC sources. Therefore, in this work, we develop a standard system for detecting emerging trends in user posts for UGC that contains some form of textual data. We demonstrate the use and implementation of this system through a case study with approximately 2 million YouTube video posts. Furthermore, to help facilitate future comparative studies in UGC trend analysis, we have made this system open-source and straightforward to integrate with various UGC systems (Twitter, Facebook, Flickr, Digg, Blogger, etc.).
Stainless Steels with Improved Oxidation Resistance for Recuperators

New materials are being evaluated to replace type 347 stainless steel in microturbine recuperators operating at higher temperatures in order to increase the efficiency of the microturbine. Commercial alloys 120 and 625 are being tested along with potentially lower cost substitutes, such as Fe-20Cr-25Ni and Fe-20Cr-20Ni. Long-term testing of these materials at 650--700 C shows excellent corrosion resistance to a simulated exhaust gas environment. Testing at 800 C has been used to further differentiate the performance of the various materials. The depletion of Cr from foils of these materials is being used to evaluate the rate of attack. Although those alloys with the highest Ni and Cr contents have longer lives in this environment, lower alloyed steels may have sufficient protection at a lower cost.
Nkx3.2-mediated Repression of Runx2 Promotes Chondrogenic Differentiation

Runx2, a transcription factor known to be essential for osteoblast maturation and skeletogenesis, is also expressed in pre-cartilaginous mesenchymal condensations in the developing embryo. It is therefore necessary to understand the control and consequential regulatory activity of the Runx2 gene within the context of chondrogenic differentiation of a mesenchymal progenitor cell. We identify the homeodomain protein Nkx3.2 as a potent sequence-specific repressor of the Runx2 promoter that acts through a regulatory element 0.1 kb upstream from the site of transcriptional initiation. The biological significance of this repression is established by utilizing bone morphogenic protein 2 (BMP-2)-induced chondrogenic differentiation of pluripotent C3H10T1/2 cells as a model for the initial events of mesenchymal chondrogenesis. We demonstrate that induction of the chondrogenic phenotype and endogenous Nkx3.2 expression is accompanied by a repression of Runx2 gene activity. Bypassing Runx2 repression by adenoviral-mediated introduction of Runx2 into C3H10T1/2 cells can prevent the induction of chondrogenesis, but cannot reverse the chondrogenic phenotype once it has been initiated, as evidenced by Sox9 and type II collagen expression and extracellular matrix deposition. Our results demonstrate that Runx2 is a direct transcriptional target of Nkx3.2, and that repression of Runx2 at the onset of chondrogenesis is a prerequisite for the activation of a chondrocyte-specific program of gene expression. We postulate that Runx2 is a critical link in BMP-2-mediated initiation of mesenchymal chondrogenesis that results in activation of Sox9 at least in part through the Nkx3.2-dependent repression of Runx2.
Generation of 10-cycle pulses from a Yb fiber laser with cubic phase compensation

We demonstrate the use of a prism-grating sequence to reduce third-order dispersion inside a modelocked Yb fiber laser. 33-fs pulses, the shortest from a fiber oscillator, can be generated with extremely clean profiles.
Improved Feynman propagators on a grid and non-adiabatic corrections within the path integral framework

Abstract The idea of using a good representation as the zeroth order description of a problem, which is widely used in perturbation theory and in basis set calculations, is extended to the path integral formulation of quantum mechanics by constructing improved Feynman propagators. The best zeroth order propagators cannot be expressed in closed form in general, and are therefore constructed numerically and stored on one-dimensional grids. Use of improved propagators in discretized path integral calculations involves a trivial modification of Monte Carlo techniques and leads to convergence with fewer time slices. Application of a quasi-adiabatic propagator to a system coupled to a harmonic bath leads to a low-dimensional path integral with a non-local influence functional which incorporates the non-adiabatic corrections to the Born—Oppenheimer approximation and which (with parameters typical of chemical processes) can be evaluated by quadrature, providing an accurate method for investigating the real time quantum dynamics of system—bath Hamiltonians.
Rhodium(I) catalysis in olefin photoreactions

The photorearrangement (254 nm) of 1,5-cyclooctadiene (1) in the presence of rhodium(I) chloride to give 1,4-cyclooctadiene (4) was found by deuterium labeling to involve an intramolecular [1,3] shift of hydrogen. A rate- determining cleavage of an allylic C--H bond is indicated by a deuterium isotope effect, k/sub H//k/sub D/ = 1.55 +- 0.03 for the 1 $Yields$ 4 rearrangement. The acyclic 1,5-diene, 3,3-dimethyl-1,5-hexadiene (8), rearranges in the presence of rhodium(I) chloride upon uv irradiation (254 nm) to give cis-3,3-dimethyl-1,4- hexadiene (10) and the trans isomer 11 in a 1:4 ratio, respectively. This observation supports a mechanism for the photorearrangement of olefins catalyzed by rhodium(I) involving an initial photodissociation of one of two rhodium(I) coordinated carbon-carbon double bonds. This results in an increase in the coordinative unsaturation of rhodium(I) and enhances the proclivity of this d/sub s/ metal atom toward oxidative addition of an allylic C--H bond. A eta$sup 3$- allylrhodium hydride intermediate then gives rearranged olefin by reductive elimination. Lastly, a novel photochemical, rhodium(I) catalyzed hydrogen transfer is reported which gives cyclooctene (7) from cyclooctadienes under unprecedentedly mild conditions. (auth)
Exploring the Complex Folding Kinetics of RNA Hairpins: II. Effect of Sequence, Length, and Misfolded States

The complexity of RNA hairpin folding arises from the interplay between the loop formation, the disruption of the slow-breaking misfolded states, and the formation of the slow-forming native base stacks. We investigate the general physical mechanism for the dependence of the RNA hairpin folding kinetics on the sequence and the length of the hairpin loop and the helix stem. For example, 1), the folding would slow down when a stable GC basepair moves to the middle of the stem; 2), hairpin with GC basepair near the loop would fold/unfold faster than the one with GC near the tail of the stem; 3), within a certain range of the stem length, a longer stem can cause faster folding; and 4), certain misfolded states can assist folding through the formation of scaffold structures to lower the entropic barrier for the folding. All our findings are directly applicable and quantitatively testable in experiments. In addition, our results can be useful for molecular design to achieve desirable fast/slow-folding hairpins, hairpins with/without specific misfolded intermediates, and hairpins that fold along designed pathways.
Electron Delocalization and the Fermi Hole

The delocalization of electrons is controlled by the Pauli exclusion principle through a corresponding delocalization of the density of the Fermi hole for electrons of given spin. It is proposed that the spatial distribution of the Fermi-hole density be used to provide a common, quantitative basis for the concept of electron delocalization, as it is used throughout chemistry. To this end, the following correspondences are made: The atomic patterns of delocalization of the Fermi hole recover the resonance structures corresponding to different possible spin-pairings and their relative importance, in terms of both energy and reactivity. The π-electron density of benzene distorted into a Kekule-like structure is shown to be less delocalized than in the symmetrical structure. The effects of a hetero ring atom and of substituents on the delocalization of the π-electrons in benzene are quantified. To illustrate the range of phenomena that are determined by the delocalization of the Fermi-hole, it is shown that ...
The Percentage Of Lipid Interstitial Fibroblasts Is Increased During Alveolarization In The Immature Rat Lung

The Percentage Of Lipid Interstitial Fibroblasts Is Increased During Alveolarization In The Immature Rat Lung
Free Energies of Hydration from a Generalized Born Model and an All-Atom Force Field

The generalized Born/surface area (GB/SA) model of Still and co-workers was originally developed using partial atomic charges for organic molecules and ions from the OPLS united-atom force field. An efficient implementation of the GB/SA approach with the OPLS-AA (all-atom) force field is described here. Migration to the OPLS-AA model allows much broader application, and it also yields improved accuracy in predicting free energies of hydration. For 75 diverse, neutral organic molecules, the mean unsigned error is 0.6 kcal/mol with the OPLS-AA GB/SA model. Furthermore, effects of hydration on conformational equilibria are shown to be well represented, and results for free energies of hydration of a wide variety of ions are also in close accord with experimental data. As an even more general alternative, the use of partial charges from the CM1A procedure of Cramer, Truhlar, and co-workers has been tested on more than 400 organic molecules and ions. OPLS-AA force field parameters are also reported for primary alkyl halides, halobenzenes, and numerous ions.
Blood bromine levels in a Pacific atoll population.

Serum and red cells from 20 Marshallese on two atolls and from 10 subjects in New York were compared for their elemental composition employing an energy dispersive X-ray fluo-rescence technique. The elements analyzed in serum included Cl, Zn, and Br, whereas red cells were analyzed for Cl, K, Fe, Zn, Br, and Rb. Both Marshallese groups showed statistically significant (P
Sources and deposition of organic matter in Cretaceous passive margin deep-sea sediments; a synthesis of organic geochemical studies from Deep Sea Drilling Project Site 603, outer Hatteras Rise

Abstract The results of organic geochemical studies of rock samples from Cretaceous strata at Site 603 on the outer Hatteras Rise are reviewed and integrated with their lithostratigraphic information. Although most of the strata contain little organic carbon, black shales enriched in organic matter were found in two settings. These rocks exist as claystones in the Aptian to Turonian Hatteras Formation and as marlstones in the Neocomian Blake-Bahama Formation. Terrigenous organic matter predominates in these deposits, except in Cenomanian and Valanginian rocks, where marine material becomes dominant. Organic carbon concentrations in Cenomanian black claystones are higher than any previously reported from the western North Atlantic, but lower than the concentrations found in the eastern North Atlantic. Black shales at Site 603 appear to result from downslope transport and rapid reburial of coastal and ocean margin sediments by turbidity flows. Deep-basin anoxia is not a major factor, except during the Cenomanian-Turonian, when the entire Atlantic Ocean may have briefly become anoxic. Organic matter in the sediments from all locations is thermally immature.
Professional Applications of Computer Technology by Members of the American Dietetic Association

Abstract LEARNING OUTCOME: To define how select members of The American Dietetic Association are currently using computer technology in the workplace. Due to their increased availability, computers have been transformed from luxuries to necessities. To assess how members of the American Dietetic Association currently use and regard computer technology in the workplace, a two-page written survey was developed in September 1996. The surveys were mailed in October 1996 to 1,271 members living in Delaware, Southeastern Pennsylvania, Southern New Jersey, and the Eastern Shore of Maryland. By December 1996, 721 surveys (56.8% return rate) were returned. Of this sample, 673 (93.3%) were complete. Surveys were analyzed using Microsoft Excel (Office 95, Version 7.0). Nutrition and dietetics professionals are trained to provide information. Currently, a productive way to store and manipulate information is by using computer technology. Through this survey, it was found that 17.0% of nutrition professionals do not use computers at work and 50.2% have never used the Internet. Self-assessed computer literacy and computer attitudes were found to be inversely associated with age. Computers can be used by nutrition professionals to improve productivity and to promote healthy lifestyles to a worldwide audience. If computer technology is not adopted, professionals may find themselves at a disadvantage due to a lack of communication skills using electronic mediums.
Three-dimensional geometric modeling of membrane-bound organelles in ventricular myocytes: bridging the gap between microscopic imaging and mathematical simulation.

Abstract A general framework of image-based geometric processing is presented to bridge the gap between three-dimensional (3D) imaging that provides structural details of a biological system and mathematical simulation where high-quality surface or volumetric meshes are required. A 3D density map is processed in the order of image pre-processing (contrast enhancement and anisotropic filtering), feature extraction (boundary segmentation and skeletonization), and high-quality and realistic surface (triangular) and volumetric (tetrahedral) mesh generation. While the tool-chain described is applicable to general types of 3D imaging data, the performance is demonstrated specifically on membrane-bound organelles in ventricular myocytes that are imaged and reconstructed with electron microscopic (EM) tomography and two-photon microscopy (T-PM). Of particular interest in this study are two types of membrane-bound Ca 2+ -handling organelles, namely, transverse tubules (T-tubules) and junctional sarcoplasmic reticulum (jSR), both of which play an important role in regulating the excitation–contraction (E–C) coupling through dynamic Ca 2+ mobilization in cardiomyocytes.
An Informatics Approach to Assess Pediatric Pharmacotherapy: Design and Implementation of a Hospital Drug Utilization System

Drug utilization in the inpatient setting can provide a mechanism to assess drug prescribing trends, efficiency, and cost-effectiveness of hospital formularies and examine subpopulations for which prescribing habits may be different. Such data can be used to correlate trends with time-dependent or seasonal changes in clinical event rates or the introduction of new pharmaceuticals. It is now possible to provide a robust, dynamic analysis of drug utilization in a large pediatric inpatient setting through the creation of a Web-based hospital drug utilization system that retrieves source data from our accounting database. The production implementation provides a dynamic and historical account of drug utilization at the authors' institution. The existing application can easily be extended to accommodate a multi-institution environment. The creation of a national or even global drug utilization network would facilitate the examination of geographical and/or socioeconomic influences in drug utilization and prescribing practices in general.
Stochastic Decomposition in M/M/∞ Queues with Markov Modulated Service Rates

Motivated by the need to study transportation systems in which incidents cause traffic to slow down, we consider an M/M/∞ queueing system subject to random interruptions of exponentially distributed durations. System breakdowns, where none of the servers work, as well as partial failures, where all servers work with lower efficiency, are investigated. In both cases, it is shown that the number of customers present in the system in equilibrium is the sum of two independent random variables. One of these is the number of customers present in an ordinary M/M/∞ queue without interruptions.
Multidimensional finite-element code for transient heat transfer calculations

A transient, multidimensional, finite-element code has been developed for predicting the time-dependent thermal field within solid geometries exposed to spatially varying, time-dependent boundary conditions. First, validation of the code is performed using both two- and three-dimensional finite-element meshes exposed to either step change or harmonically varying boundary conditions. Numerical predictions from the simulation are in very good agreement with analytical solutions for all types of elements and boundary conditions considered. Subsequently, the effects of time step, sampling frequency of harmonic boundary conditions, and grid density on solution accuracy and convergence are explored. The results suggest appropriate time stepping strategies for the time derivative of temperature, and optimum sampling rates for harmonic boundary conditions. Guidelines for mesh refinement near boundary surfaces are also furnished.
Phylogenetic Analysis and the Evolution of the 18S rRNA Gene Typing System of Acanthamoeba

Species of Acanthamoeba were first described using morphological characters including cyst structure and cytology of nuclear division. More than 20 nominal species were proposed using these methods. Morphology, especially cyst shape and size, has proven to be plastic and dependent upon culture conditions. The DNA sequence of the nuclear small-subunit (18S) rRNA, the Rns gene, has become the most widely accepted method for rapid diagnosis and classification of Acanthamoeba. The Byers-Fuerst lab first proposed an Rns typing system in 1996. Subsequent refinements, with an increasing DNA database and analysis of diagnostic fragments within the gene, have become widely accepted by the Acanthamoeba research community. The development of the typing system, including its current state of implementation is illustrated by three cases: (i) the division between sequence types T13 and T16; (ii) the diversity within sequence supertype T2/T6, and (iii) verification of a new sequence type, designated T20. Molecular studies make clear the disconnection between phylogenetic relatedness and species names, as applied for the genus Acanthamoeba. Future reconciliation of genetic types with species names must become a priority, but the possible shortcomings of the use of a single gene when reconstructing the evolutionary history of the acanthamoebidae must also be resolved.
Aerobic fitness and resting energy expenditure in young adult males

Ambiguous findings have been reported in previous studies regarding the relationships among aerobic fitness, resting metabolic rate (RMR), and the thermic effect of a meal (TEM). We reexamined the association among these variables in young nonobese men who exhibited a wide range of aerobic fitness levels. RMR was measured after an overnight fast and TEM was assessed for three hours after ingestion of a liquid meal. Preprandial and postprandial plasma levels of insulin, glucose, and thyroid hormones (total T3 and T4) were measured. Daily energy intake was estimated from three-day food diaries, body composition from underwater weighing, and aerobic fitness from a test of VO2 max. Data were analyzed with linear and curvilinear regression analysis, as well as with ANOVA to test for differences among subjects classified by fitness level (ie, untrained, moderately, and highly trained). A significant correlation was found between RMR and VO2 max (r = .77, P < .01). RMR adjusted for body weight and FFW was higher in highly trained men when compared to moderately and untrained individuals. However, a curvilinear relationship was found between TEM and VO2 max (P < .05). Subjects who exhibited moderate levels of fitness showed the highest TEM, whereas a lower TEM was noted in untrained and highly trained men. These findings were observed in the absence of differences in plasma concentrations of total T3 and T4 among fitness levels. These findings suggest that highly trained men have a high RMR adjusted for their metabolic size. TEM varied in a curvilinear manner with fitness level, with the highest thermic response found in subjects with moderate levels of aerobic fitness. These data suggest that aerobic fitness in young, nonobese men may be a factor contributing to individual variation in RMR and postprandial thermogenesis.
Energy transfer between chromophore and protein in phycocyanin

Abstract The efficiency with which light, absorbed partly by the protein, excites fluorescence of phycocyanin in pure solutions is the same as that of the light absorbed by only the chromophore moiety of the phycocyanin molecule. About 46% of the absorption in the peak at 277 mμ band of phycocyanin is attributable to absorption by the tryptophan and tyrosine constituents of the protein; the chromophore contributes the remaining 54 %. It can be concluded that the conversion of the “ultraviolet” excitation quanta of the protein into “red” quanta of the chromophore occurs in the phycocyanin molecule with the same efficiency as the transformation of “ultraviolet” into “red” excitation quanta within the chromophore itself. The mechanism of this intramolecular transfer probably is similar to that of the intermolecular transfer responsible for the sensitized fluorescence of atoms (such as sodium fluorescence sensitized by mercury vapor), or molecules (such as chlorophyll-a fluorescence sensitized by a carotenoid or phycobilin).
Tsunami and Its Hazards in the Indian and Pacific Oceans

The 26 December 2004 earthquake and tsunami that struck offshore the Sumatra-Andaman islands with tragic effects on inhabitants around the Indian Ocean is obviously a key event in the Earth sciences. Much like other critical topics of recent years, such as environmental issues and climate change, the earthquake and tsunami affected our science in many ways, while also connecting our science with the public policy arena. Our previous understanding of these enormous earthquakes and their resulting tsunamis had been limited to two previous magnitude 9+ events, the Chile and Alaska earthquakes of the 1960s. At that time, digital recording of global seismic data was not standard practice, and other data sets were equally limited.
On the Source of Organic Acid Aerosol Layers above Clouds

During the July 2005 Marine Stratus/Stratocumulus Experiment (MASE) and the August−September 2006 Gulf of Mexico Atmospheric Composition and Climate Study (GoMACCS), the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter probed aerosols and cumulus clouds in the eastern Pacific Ocean off the coast of northern California and in southeastern Texas, respectively. An on-board particle-into-liquid sampler (PILS) quantified inorganic and organic acid species with ≤5-min time resolution. Ubiquitous organic aerosol layers above cloud with enhanced organic acid levels were observed in both locations. The data suggest that aqueous-phase reactions to produce organic acids, mainly oxalic acid, followed by droplet evaporation is a source of elevated organic acid aerosol levels above cloud. Oxalic acid is observed to be produced more efficiently relative to sulfate as the cloud liquid water content increases, corresponding to larger and less acidic droplets. As derived from large eddy simulations of stratocumulus under the conditions of MASE, both Lagrangian trajectory analysis and diurnal cloudtop evolution provide evidence that a significant fraction of the aerosol mass concentration above cloud can be accounted for by evaporated droplet residual particles. Methanesulfonate data suggest that entrainment of free tropospheric aerosol can also be a source of organic acids above boundary layer clouds.
An empirical investigation of the Herzberg methodology and two-factor theory

Abstract An empirical test of the Herzberg methodology and two-factor theory was carried out using several comparable sets of data collected from the same subjects. The protocol methodology (story-content analysis) used by Herzberg and many replications was utilized twice, at six-week intervals. Ranking of factor importance and motivator—hygiene identification by the subjects also provided data sets. The results failed to support the Herzberg methodology as a reliable measure of job satisfaction or the two-factor theory as valid. Greater differences were found between motivator/motivator and hygiene/hygiene sequence comparisons than between motivator/hygiene comparisons.
(E)pistemological Awareness, Instantiation of Methods, and Uninformed Methodological Ambiguity in Qualitative Research Projects:

This article explores epistemological awareness and instantiation of methods, as well as uninformed ambiguity, in qualitative methodological decision making and research reporting. The authors argue that efforts should be made to make the research process, epistemologies, values, methodological decision points, and argumentative logic open, accessible, and visible for audiences. To these ends, they discuss two ways of conceptualizing the role of epistemological awareness and instantiation of methods, including (a) a series of decision junctures and (b) a spatial conceptualization of epistemological decision making. Through an analysis of researchers’ decision junctures drawn from studies published in high-impact education journals in 2006, the authors illustrate current methodological awareness and instantiation of methods in the field of education research.
Carbon-13 nuclear magnetic resonance studies of the aldol condensation products of acetone on an activated alumina catalyst

Abstract The aldol condensation of acetone adsorbed on alumina is monitored with C-13 NMR. The detectability of the major reaction products, diacetone alcohol, mesityl oxide, phorone, isophorone, and mesitylene, is compared to that previously observed using infrared and gas Chromatographic methods.
A framework for feature selection in clustering

We consider the problem of clustering observations using a potentially large set of features. One might expect that the true underlying clusters present in the data differ only with respect to a small fraction of the features, and will be missed if one clusters the observations using the full set of features. We propose a novel framework for sparse clustering, in which one clusters the observations using an adaptively chosen subset of the features. The method uses a lasso-type penalty to select the features. We use this framework to develop simple methods for sparse K-means and sparse hierarchical clustering. A single criterion governs both the selection of the features and the resulting clusters. These approaches are demonstrated on simulated and genomic data.
Prevalence of Self-Reported High Blood Pressure Awareness, Advice Received From Health Professionals, and Actions Taken to Reduce High Blood Pressure Among US Adults—Healthstyles 2002

High blood pressure awareness, advice received from health care providers, and adoption of heart-healthy behaviors were assessed using the Healthstyles 2002 survey. About 20% of respondents reported that they had high blood pressure, and 53% of these were currently taking medications to lower blood pressure. Black men had the highest adjusted prevalence of high blood pressure (32%). Medication use among persons with high blood pressure was lower among Hispanics (45%) than among blacks (54%) and whites (54%). Persons reporting having high blood pressure were five times more likely to report having received advice from a health care professional to go on a diet or change eating habits (p<0.05) and reduce salt or sodium in their diet (p<0.05), but five times less likely to have received advice to exercise (p<0.05) than those reporting not having high blood pressure, after adjustment for differences in sex, race/ethnicity, and age. Persons with self-reported high blood pressure were also more likely to be making these modifications (p<0.05). Among people with high blood pressure, current medication use was associated with both receiving and following advice for diet change and salt reduction (p<0.05). Future initiatives are needed to improve the proportion of Hispanics and blacks taking prescribed medications to improve high blood pressure control and reduce risk for serious sequelae such as heart disease and stroke.
Integrated photonic systems based on transformation optics enabled gradient index devices

Integrated photonics is expected to play an increasingly important role in optical communications, imaging, computing and sensing with the promise for significant reduction in the cost and weight of these systems. Future advancement of this technology is critically dependent on an ability to develop compact and reliable optical components and facilitate their integration on a common substrate. Here we reveal, with the utility of the emerging transformation optics technique, that functional components composed of planar gradient index materials can be designed and readily integrated into photonic circuits. The unprecedented design flexibility of transformation optics allows for the creation of a number of novel devices, such as a light source collimator, waveguide adapters and a waveguide crossing, which have broad applications in integrated photonic chips and are compatible with current fabrication technology. Using the finite-difference time-domain method, we perform full-wave numerical simulations to demonstrate their superior optical performance and efficient integration with other components in an on-chip photonic system. These components only require spatially-varying dielectric materials with no magnetic properties, facilitating low-loss, broadband operation in an integrated photonic environment. Using transformation optics, researchers have built miniature gradient-index components for collimating, coupling and splitting light beams. Transformation optics is a popular theoretical approach for designing novel metamaterial-based photonic devices such as invisibility cloaks and perfect light absorbers. Qi Wu, Jeremiah Turpin and Douglas Werner from The Pennsylvania State University in the USA have now used transformation optics to design miniature gradient-index components. The small size and all-dielectric nature of these components means that they can be easily implemented by standard nanofabrication techniques such as silicon-on-insulator patterning, and are well-suited for integration with planar on-chip photonic systems. The researchers suggest that the approach could also yield nanoscale circuitry for controlling surface plasmons in applications such as optical communications, computing and sensing.
Correlation of outer nuclear layer thickness with cone density values in patients with retinitis pigmentosa and healthy subjects.

Author(s): Menghini, Moreno; Lujan, Brandon J; Zayit-Soudry, Shiri; Syed, Reema; Porco, Travis C; Bayabo, Kristine; Carroll, Joseph; Roorda, Austin; Duncan, Jacque L | Abstract: PurposeWe studied the correlation between outer nuclear layer (ONL) thickness and cone density in normal eyes and eyes with retinitis pigmentosa (RP).MethodsSpectral-domain optical coherence tomography (SD-OCT) scans were acquired using a displaced pupil entry position of the scanning beam to distinguish Henle's fiber layer from the ONL in 20 normal eyes (10 subjects) and 12 eyes with RP (7 patients). Cone photoreceptors were imaged using adaptive optics scanning laser ophthalmoscopy. The ONL thickness and cone density were measured at 0.5° intervals along the horizontal meridian through the fovea nasally and temporally. The ONL thickness and cone density were correlated using Spearman's rank correlation coefficient r.ResultsCone densities averaged over the central 6° were lower in eyes with RP than normal, but showed high variability in both groups. The ONL thickness and cone density were significantly correlated when all retinal eccentricities were combined (r = 0.74); the correlation for regions within 0.5° to 1.5° eccentricity was stronger (r = 0.67) than between 1.5° and 3.0° eccentricity (r = 0.23). Although cone densities were lower between 0.5° and 1.5° in eyes with RP, ONL thickness measures at identical retinal locations were similar in the two groups (P = 0.31), and interindividual variation was high for ONL and cone density measures. Although ONL thickness and retinal eccentricity were important predictors of cone density, eccentricity was over 3 times more important.ConclusionsThe ONL thickness and cone density were correlated in normal eyes and eyes with RP, but both were strongly correlated with retinal eccentricity, precluding estimation of cone density from ONL thickness. (ClinicalTrials.gov number, NCT00254605.).
Post Porosity Plasma Protection applied to a wide range of ultra low-k materials

Integration challenges of porous ultra low-k (ULK) materials resulting from the ULKs' high sensitivity to process damage constitute a major roadblock to their implementation in back-end-of-the-line wiring structures for advanced technology nodes. The Post Porosity Plasma Protection strategy, which we introduced last year, enables to shield the ULKs' porosity during key integration steps. We report here on the feasibility of the protection across a wider range of dielectric constants and the advantages offered by our strategy during integration in terms of critical dimension integrity and electrical properties.
Translation of a unique transcript for protein isoaspartyl methyltransferase in haploid spermatids: implications for protein storage and repair.

The mammalian testis contains high levels of a protein, L-isoaspartyl (D-aspartyl) O-methyltransferase (PIMT), postulated to play a role in the repair of age-damaged proteins. To examine the regulation of PIMT concentrations during the development of spermatozoa, poly(A)+ RNA was isolated from purified populations of pachytene spermatocytes and round spermatids. Northern blot analysis revealed that a unique 1.1-1.3 kb PIMT transcript is present in preparations of round spermatid and pachytene spermatocyte poly (A)+ RNA. The concentration of this small PIMT transcript is at least four times higher in mRNA isolated from round spermatids than in mRNA isolated from pachytene spermatocytes, indicating that the PIMT gene is actively transcribed during the haploid phase of spermatogenesis. The germ cell-specific PIMT transcripts are distributed between the polysomal fraction and the nonpolysomal fractions of testis RNA, suggesting that translational controls also contribute to the high concentrations of PIMT in mammalian sperm. PIMT function is not essential for spermatogenesis because the testes from transgenic mice lacking PIMT activity have normal levels of protamine transcripts, and because functional sperm can be recovered from the cauda epididymis. The protein repair function of the PIMT may be more important in maintaining the fertilization competence of translationally-inactive mature sperm during the prolonged period of epididymal transit and storage in the male reproductive tract.
Stereospecificity of linoleic acid hydroperoxide isomerase from corn germ

Linoleic acid hydroperoxide isomerase from corn germ inverted the stereoconfiguration of its substrate. 9-D(S)-Hydroperoxy-trans-10,cis-12-octadecadienoic acid was converted to 10-oxo-9-L(R)-hydroxy-cis-12-octadecenoic acid. Presumably, the H2O solvent of OH− acted as a nucleophile. In the presence of another nucleophile, linoleate, the 9-D(S)-hydroperoxide was transformed into 9-L(R)-linoleoyloxy-10-oxo-cis-12-octadecenoic acid. The substitution of nucleophiles from the incubation solution and the inversion of stereoconfiguration at carbon-9 are consistent with a bimolecular nucleophilic substitution (SN2) mechanism.
Two Forms of Chlorophyll a in vivo with Distinct Photochemical Functions

Action spectra of the Emerson effect in Chlorella and Navicula reveal peaks at 670 mut, in addition to those at 650 mu (Chlorella) and 630 mµ (Navicula) attributable to chlorophylls b and c. Thus, excitation of chlorophyll a form "chlorophyll a 670" can supplement, in these algae, the excitation of the form "chlorophyll a 680-700." The effect of the auxiliary pigments in these algae may be mediated by energy transfer to "chlorophyll a 670."
All-fibre sensing loop using pulse-modulated light-emitting diode

A sensing system is presented which includes a pulse-modulated light-emitting diode (LED) and an all-fibre-optic loop generating a reference signal in the time domain. The basic principle of operation and parameters are introduced, and some properties of such a system are experimentally examined using a microbend sensor.
Screening for novel bacteria from the bioenergy feedstock switchgrass (Panicum virgatum L.).

Switchgrass is considered as a good candidate for biofuel, especially ethanol production due to its huge biomass output and high cellulose content. In a search for novel microorganisms capable of using and degrading switchgrass to produce sugars and ethanol, enrichment experiments were established to screen for microorganisms from soil samples obtained at the University of Tennessee Agricultural Research Station, Jackson, Tennessee. Three enrichments were prepared and incubated at different pH and temperatures: (1) 30°C, pH 5, (2) 30°C, pH 8 and (3) 60°C, pH5. Bulk community DNA was directly extracted from the enrichments. Microbial community structures were determined by phylogenetic analysis of 16S rRNA gene sequences retrieved from the enrichment cultures containing switchgrass as the carbon source. The mesophilic enrichments were dominated by Sarcina, Anaerobacter, and Clostrium, which were not found in the thermophilic enrichment. The thermophilic enrichment selected for two types of bacteria belongi...
Uncertainty in the ocean–atmosphere feedbacks associated with ENSO in the reanalysis products

The evolution of El Nino-Southern Oscillation (ENSO) variability can be characterized by various ocean–atmosphere feedbacks, for example, the influence of ENSO related sea surface temperature (SST) variability on the low-level wind and surface heat fluxes in the equatorial tropical Pacific, which in turn affects the evolution of the SST. An analysis of these feedbacks requires physically consistent observational data sets. Availability of various reanalysis data sets produced during the last 15 years provides such an opportunity. A consolidated estimate of ocean surface fluxes based on multiple reanalyses also helps understand biases in ENSO predictions and simulations from climate models. In this paper, the intensity and the spatial structure of ocean–atmosphere feedback terms (precipitation, surface wind stress, and ocean surface heat flux) associated with ENSO are evaluated for six different reanalysis products. The analysis provides an estimate for the feedback terms that could be used for model validation studies. The analysis includes the robustness of the estimate across different reanalyses. Results show that one of the “coupled” reanalysis among the six investigated is closer to the ensemble mean of the results, suggesting that the coupled data assimilation may have the potential to better capture the overall atmosphere–ocean feedback processes associated with ENSO than the uncoupled ones.
Speaking fundamental frequency characteristics of white, African American, and Hispanic kindergartners.

Speech samples from groups of White, African American, and Hispanic kindergarten-age children were compared on measures of mean speaking fundamental frequency (Fo), maximum and minimum speaking Fo, pitch sigma, and speaking range (in semitones). Results indicate that there are significant differences between racial groups on measures of mean speaking Fo and speaking range. In particular, the Hispanic children were observed to have increased mean speaking FOS in comparison with the African American children and reduced speaking ranges as compared to both African American and White racial groups. Results indicate that the speech-language pathologist must exercise discretion when assessing the speaking Fo characteristics (particularly mean speaking Fo and speaking range) of children from different racial groups.