cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of protistan grazing on the frequency of dividing cells in bacterioplankton assemblages.

Grazing by phagotrophic flagellates and ciliates is a major source of mortality for bacterioplankton in both marine and freshwater systems. Recent studies have demonstrated a positive relationship between clearance rate and prey size for bacterivorous protists. We tested the idea that, by selectively grazing the larger (more actively growing or dividing) cells in a bacterial assemblage, protists control bacterial standing stock abundances by directly cropping bacterial production. Samples of estuarine water were passed through 0.8-μm-pore-size filters (bacteria only) or 20-μm-mesh screens (bacteria and bacterivorous protists) and placed in dialysis tubing suspended in 7 liters of unfiltered water. Changes in total bacterial biovolume per milliliter (bacterial biomass), frequency of dividing cells (FDC), and average per cell biovolume were followed over a period of 24 h. In three experiments, the FDC increased more rapidly and attained higher values in water passed through 0.8-μm-pore-size filters (average, 5.1 to 8.9%; maximum, 15.5%) compared with FDC values in water passed through 20-μm-mesh screens (average, 2.7 to 5.3%; maximum, 6.7%). Increases in bacterial biomass per milliliter lagged behind increases in FDC by about 4 to 6 h. Grazed bacterial assemblages were characterized by lower total biomasses and smaller average cell sizes compared with those of cells in nongrazed assemblages. We conclude that bacterivorous protists control bacterial standing stock abundances partly by preferentially removing dividing cells. Selective grazing of the more actively growing cells may also explain, in part, the ability of slow-growing cells to persist in bacterioplankton assemblages.
The Annoyingly Indeterminate Effect of Sex Differences

At present, men and women have different distributions of certain aptitudes and personality traits. A growing body of research suggests that some of these differences have some biological basis, although these distribution differences do not always conform neatly to traditional stereotypes and cultural factors also contribute. A heritable basis for difference, however, has frustratingly indeterminate implications. It suggests that some occupational segregation is not caused by discrimination. At the same time, a statistical aptitude or temperament difference will almost inevitably cause discrimination in professions that make use of that aptitude or temperament. This implication is supported by empirical evidence about the continued existence of discrimination from disparate sources, including labor market data and experimental laboratory studies in both economics and psychology. The offsetting effects of difference and statistical discrimination make it extremely difficult to predict the degree of occupational segregation in a non-discriminatory world. To complicate matters further, there is no simple relation between the size of ability differences and the efficient degree of occupational segregation. The principle of comparative advantage suggests that even small ability differences might produce large degrees of occupational segregation. Conversely, high demand in a sector using skills that favor one sex may draw the other sex into sectors in which they have an absolute disadvantage. Ability distribution differences create tremendous challenges for anti-discrimination policy. Liability rules based on current labor market representation are of minimal use, since the labor market reflects existing discrimination. Though perhaps useful in the short term, long-term numerical targets are problematic: target goals are extremely difficult to set, and would need to become a permanent institution. Moreover, numerical targets may create unintended problems for women. Men have historically dominated even fields in which women have an advantage. A target goal of equal representation would prevent women from attaining majority status in these fields. Closer scrutiny of employer practices holds promise as an alternative to numerically based theories. Earlier versions of this paper were circulated with the title "The Paradox of Statistical Discrimination"
SIR-C/X-SAR mapping snow in alpine region

This paper demonstrates the capability of SIR-C/X-SAR in mapping seasonal snow cover in an alpine region. The polarization properties at each frequency, the ratios from different frequencies and the synthesized polarization measurements are little affected by topography. Through evaluated angular dependence and separabilities of each target within the scenes, the authors can determine the optimal measurement set for classification performance. In contrast to a single polarization SAR, SIR-C/X-SAR has capability to map both dry and wet snow covers and suitable for large scale snow mapping.
Factors That Impact Transitions between a Regular-Educational Program and a Gifted Program: The Perceptions of Four African-American Males:

Several programmatic strategies for gifted students involve removal from the regular classroom in order to attend special schools, resource rooms, or enrichment classes. The focus of this study was on factors that influenced transitions between a regular-educational program and a gifted program, based on the perceptions of four African-American males. Using a case-study approach, qualitative data from students, parents, and teachers were collected and analyzed. Critical factors that contributed to the students' ability to adapt to the transitions were the perception of a strong family unit; development of goals for the future; socialization factors, which included student personality and peer influences; the perceived benefits of their participation in the gifted program; discrepancies between identification and placement; and a discrepancy in the manner in which material was presented in the various programs.
Towards a Characterization of Modern Opera

Herbert Lindenberger regards the modern canon as “not quite opera” in its resistance to the theatricality of traditional opera, its forays into popular musical forms, and its use of imitation and parody to quote opera of the past. In his view, modern opera divides itself into two kinds: the “hard” and the “soft.” Lindenberger goes on to consider the question of postmodern opera, but he is less persuaded now than he was previously that this is a useful term, especially given the extent to which one can find so-called “postmodern” elements in “modernist” operas.
Allometric influence on phenotypic variation in the Song Sparrow (Melospiza melodia)

Song Sparrow (Melospiza melodia) populations found along the Pacific Coast of North America, from Baja California to the islands off the coast of Alaska, exhibit extensive morphological variation. With a multivariate analysis of size and shape, I describe a portion of this pattern and examine how it could be maintained despite gene flow among the populations. Because shape differences fall along geographic barriers, I suggest that similarities among Song Sparrow populations in multivariate shape reflect their pattern of genetic relatedness. A general pattern of Song Sparrow post-nestling growth allometry has been discovered: bill characteristics are positively allometric and all other characteristics are negatively allometric. In contrast to shape, multivariate patterns of body size variation do not correspond to geographic relationships. In combination with evidence of Song Sparrow phenotypic plasticity, it is proposed that multivariate body size is an environmentally plastic trait and that specific traits exhibit levels of phenotypic plasticity in proportion to their rate of growth with respect to body size. In this way local environmental factors which alter body size may change an entire suite of allometrically related traits and thus create striking patterns of morphological variation.
Brook Trout (Salvelinus fontinalis) Habitat use and Dispersal Patterns in New York Adirondack Mountain Headwater Streams

Minimal research has been conducted involving Salvelinus fontinalis (Brook Trout) habitat use and dispersal patterns within Adirondack Mountain headwater streams. Hence, fishery managers are left with information gaps regarding the specific habitat conditions characteristic of sustainable Brook Trout populations in Adirondack flowing waters. Through the use of single-pass electrofishing and markrecapture techniques, size-class specific microhabitat use and reach-scale movement patterns for Brook Trout were examined within two northern Adirondack streams. Water depth, water velocity, and sub strate-size use were observed to be similar among two Brook Trout size classes. Both size classes exhibited use patterns within deeper slowermoving pool habitats; however, larger Brook Trout were found to be associated with smaller-sized substrates within one of our study sites. These habitat-use patterns were also supported by comparison of stream hydrologic condition, including Froude number. Brook Trout movement patterns were found to be dependent on both size class and season. Smaller-sized trout exhibited increased movement during the spring, whereas larger trout were found to be more mobile and move more frequently during early fall. Lastly, we examined the proportion of Brook Trout moving upstream/downstream and found a greater frequency of smaller Brook Trout moving upstream during late summer.
Electrical resistance and stem water relations in Verticillium‐infected red maple1

An inverse relationship exists between stem water potential and electrical resistance (ER) in healthy red maple Acer rubrum L. (r = - .93 to r = - .98). Stem ER of red maple seedlings was measured at 1 to 2 day intervals during a 14 week course of infection by Verticillium dahliae Klebahn. No significant differences (P = .05) in ER were found between moderately to severely infected and control plants, although stem water potential of infected plants was significantly lower than the control plants. In plants which displayed only slight if any symptoms and in which no significant change in stem water potential occurred, ER of the infected plants was significantly lower than that of the control plants.
Plasmodium gallinaceum: fine structure by freeze-etch technique.

Abstract The fine structure of the obligate intracellular parasite Plasmodium gallinaceum was examined by the freeze-etching technique. The characteristics of this malarial parasite, from the early trophozoite stage to the segmenting schizont stage were studied, and structural aspects of each stage were examined. The malarial parasite was shown to have cytoplasmic and nuclear membrane characteristics which differ considerably from those of the host. Two types of discontinuities in the nuclear membranes of the parasites were noted. These were a small pore system in the inner nuclear membrane and a large pore system in the outer membrane. The cytoplasmic membranes of the parasite were more coarsely granular than those of the host. The outer parasite membrane which has been reported to be of host origin also differs considerably in structure from the erythrocyte membrane. This could be due to modifications after envelopment of the parasite, or could indicate another origin for the membrane.
Exploring the relationship between physical well-being and healthy lifestyle changes among European- and Latina-American breast and cervical cancer survivors.

Background: Cancer and its treatments have a lingering and often negative impact on survivors' physical well-being. The physical sequelae impinge on daily functioning and overall HRQOL, and perhaps influence lifestyle changes post-cancer. This study aims to examine: (1) physical well-being items that are associated with low overall health-related quality of life; and (2) the relationship between physical well-being outcomes and healthy lifestyle changes by cancer type. Methods: This study employed a cross-sectional design with mixed sampling methods. In total 922 European- (n=452) and Latina-American (n=470) breast (BCS) or cervical cancer survivors (CCS) were recruited from the California Cancer Surveillance Program and Los Angeles area hospital registries. Item responses from survivors in the lowest quartile of total quality of life scores and percentages reflecting low physical well-being levels were calculated. Results: A statistical approach to individual items provides unique and valuable measurement and clinical information above and beyond physical well-being total scores. Physical well-being item responses varied according to ethnicity, income, and education. BCS and CCS showed different patterns in the relationship between physical well-being items and lifestyle changes. Specifically, exercise was significantly related to physical well-being items for BCS, while diet changes were significantly associated with physical well-being for CCS. Conclusions: Results reveal unique correlates of physical well-being items by cancer type, ethnicity, and lifestyle changes. Clinically, this study highlights the need for greater consideration of individual and medical characteristics in developing culturally sensitive and patient responsive interventions to promote healthy lifestyles and improve survivorship outcomes. Copyright © 2010 John Wiley & Sons, Ltd.
Benzochromenones from the Marine Crinoid Comantheria rotula Inhibit Hypoxia-Inducible Factor-1 (HIF-1) in Cell-Based Reporter Assays and Differentially Suppress the Growth of Certain Tumor Cell Lines

Hypoxia-inducible factor-1 (HIF-1) is a transcription factor that promotes tumor cell adaptation and survival under hypoxic conditions. HIF-1 is currently recognized as an important molecular target for anticancer drug discovery. The National Cancer Institute open repository of marine invertebrates and algae lipid extracts was evaluated using a T47D breast tumor cell-based reporter assay for HIF-1 inhibitory activity. Bioassay-guided fractionation of an active extract from a crinoid Comantheria rotula yielded seven benzo[g]chromen-4-one and benzo[h]chromen-4-one pigments (1-7). The structures of the new benzo[g]chromenone dimer 9,9'-oxybis-neocomantherin (1) and another new natural pigment 5 were deduced from spectroscopic and spectrometric data. The crinoid pigments significantly inhibited both hypoxia-induced and iron chelator-induced HIF-1 luciferase reporter activity in breast and prostate tumor cells. However, inhibition of HIF-1 in the reporter assay did not translate into a significant decrease in the expression of the downstream HIF-1 target, secreted vascular endothelial growth factor (VEGF). Compound 1 was found to inhibit tumor cell growth in the NCI 60-cell line panel (GI(50) values of 1.6-18.2 microM), and compound 6 produced a unique pattern of tumor cell growth suppression. Five cell lines from different organs were hypersensitive to 6 (GI(50) values of 0.29-0.62 microM), and three others were moderately sensitive (GI(50) values of 2.2-5.1 microM), while the GI(50) values for most other cell lines ranged from 20 to 47 microM. Crinoid benzo[g]chromenones were also found to scavenge radicals in a modified DPPH assay.
Flourishing, Substance Use, and Engagement in Students Entering College: A Preliminary Study.

Abstract Objective: The present study explores the association between positive mental health or flourishing, depression, and engaged learning in undergraduates. Participants: Entering first year students (N = 428) at a liberal arts college. Methods: Students completed measures of depression, flourishing, substance use, and student engagement. Results: Based on Keyes’ model of mental health, 1 69.1% of students were flourishing, 29.0% were moderately mentally healthy, and 1.9% were languishing. In addition, 21.8% of students had elevated depression scores, and these scores were highly correlated with languishing. Alcohol consumption and binge drinking were not associated with measures of mental health. However, certain kinds of student engagement were associated with flourishing. Conclusions: Results suggest more flourishing in this sample entering college than in previous studies of high school students or adults. Future research should explore flourishing in undergraduates in more diverse samples across...
Variable Contributions of Tyrosine Residues to the Structural and Spectroscopic Properties of the Factor for Inversion Stimulation

The diverse roles of tyrosine residues in proteins may be attributed to their dual hydrophobic and polar nature, which can result in hydrophobic and ring stacking interactions, as well as hydrogen bonding. The small homodimeric DNA binding protein, factor for inversion stimulation (FIS), contains four tyrosine residues located at positions 38, 51, 69, and 95, each involved in specific intra- or intermolecular interactions. To investigate their contributions to the stability, flexibility, and spectroscopic properties of FIS, each one was independently mutated to phenylalanine. Equilibrium denaturation experiments show that Tyr95 and Tyr51 stabilize FIS by about 2 and 1 kcal/mol, respectively, as a result of their involvement in a hydrogen bond-salt bridge network. In contrast, Tyr38 destabilizes FIS by about 1 kcal/mol due to the placement of a hydroxyl group in a hydrophobic environment. The stability of FIS was not altered when the solvent-exposed Tyr69 was mutated. Limited proteolysis with trypsin and V8 proteases was used to monitor the flexibility of the C-terminus (residues 71-98) and the dimer core (residues 26-70), respectively. The results for Y95F and Y51F FIS revealed a different proteolytic susceptibility of the dimer core compared to the C-terminus, suggesting an increased flexibility of the latter. DNA binding affinity of the various FIS mutants was only modestly affected and correlated inversely with the C-terminal flexibility probed by trypsin proteolysis. Deconvolution of the fluorescence contribution of each mutant revealed that it varies in intensity and direction for each tyrosine in WT FIS, highlighting the role of specific interactions and the local environment in determining the fluorescence of tyrosine residues. The significant changes in stability, flexibility, and signals observed for the Y51F and Y95F mutations are attributed to their coupled participation in the hydrogen bond-salt bridge network. These results highlight the importance of tyrosine hydrogen-bonding and packing interactions for the stability of FIS and demonstrate the varying roles that tyrosine residues can play on the structural and spectroscopic properties of even small proteins.
Automatic procedure for the microestimation of 2,3-diphosphoglycerate.

Abstract A simple, rapid, and reproducible automated method for the microestimation of 2,3-diphosphoglycerate is presented. The method allows the estimation of 2,3-diphosphoglycerate in dilutions of normal blood of the order of 1:1000 and below; it should be useful in clarifying the relation of 2,3-diphosphoglycerate to oxygen affinity and changes of this important intermediate in diseases such as sickle-cell anemia. Recoveries and normal values of 2,3-diphosphoglycerate in packed red cells and in whole blood are presented. A practical simple procedure to maintain autoanalyzers free of obstructions due to protein precipitation is described.
Cytochrome c folding traps are not due solely to histidine-heme ligation: direct demonstration of a role for N-terminal amino group-heme ligation.

Abstract In previous work, heme ligation effects on the folding of cytochrome c have been attributed to histidine side-chains. A variant of yeast iso-1-cytochrome c designated TM, which lacks all histidine residues except His18, still shows evidence of denatured state heme ligation in the pH range between 5 and 6 where normally only histidine ligation is expected. Conversion of the N-terminal amino group of TM to a carbonyl group through a transamination reaction with glyoxylate produced a protein (ModTM) with no terminal amino group. The midpoint pH (pH1/2) for loss of heme ligation in 3 M guanidine-HCl shifts from 5.9 to 7.4 as a result of this modification, providing direct evidence for N-terminal amino group-heme ligation under these conditions. The N-terminal amino group thus competes with histidine for misligation of iso-1-cytochrome c under denaturing conditions. To assess the effect of denatured state N-terminal amino group-heme ligation on the folding of iso-1-cytochrome c, stopped-flow kinetics experiments were conducted. At pH 6.2, the major refolding lifetimes (3 M → 0.27 M guanidine-HCl) for ModTM, TM and the wild-type protein are 11.6 ms, 30 ms and 1.3 seconds, respectively. Denatured state ligation of the N-terminal amino group thus slows folding 2.6-fold.
Learning is bitter and sweet in ventral striatum.

The ventral striatum (VS) plays a key role in motivationally guided learning. Setlow et al. show that VS neurons encode the significance of cues associated with both aversive and rewarding outcomes and that this neural linkage develops over time in a fashion roughly paralleling the expression of learned behavior. Subpopulations of VS neurons may contribute distinct signals to the learning process, reflecting either cue significance or learned sensory-motor associations.
Confidence of paternity and wife-sharing in polygynous and polyandrous systems

Abstract If the risk of cuckoldry increases with the size of a polygynous male's harem, the male should pursue such adaptations as guarding of wives and wife-sharing with relatives (increasing relatedness to him of his wives' offspring). High risk of cuckoldry might sometimes favor formation of polyandrous trios even when the offspring of polyandrous females do no better than those of monogamous females.
Wave propagation in a circular rod made of an elastic diatomic material

Abstract The paper concerns propagation of plane longitudinal waves in a long circular rod made of an elastic material whose particles include two atoms of different thermomechanical properties. After establishing the constitutive equations of the constituent materials making up the diatomic material, equations of motion are solved using four quasi-potential functions. Satisfaction of the boundary conditions imposed yields four dispersion equations, analyzed in more detail for relaxed bonds between the constituent materials. A numerical example is illustrated by a graph.
Parameters of a micro-theory of instruction

Types of instructional theory are defined and a brief review of literature given. A sample of an integrated learning model is presented, based on Pascual-Leone's theory of constructive operators: then, exemplary postulates are developed from the learning model and a theorem is derived from the postulates. The implications of the theorem are discussed in relation to instructional practice, models of learning, and future theory development.
Simulating arbitrary response curves with available response curves for SLMs

Until now, the input/output response curve of a SLM has been regarded as a given. Often the curve we are given is not the curve we want, but we have no choice. We show that if it is possible to induce any sort of significant changes in the response curve, then we can simulate in parallel an almost arbitrary response curve using the available variations of response curves.
A clinical pathway for postoperative management and early patient discharge: does it work in gynecologic oncology?

Objective This study evaluates a postoperative clinical pathway among gynecologic oncology patients. Study Design 880 surgical admissions were retrospectively reviewed at an institution which used a clinical pathway consisting of early feeding and ambulation as well as prompt discontinuation of intravenous fluids with conversion to oral analgesics. Readmission, mortality, and complication rates were calculated. Patient proportions were compared by using the χ 2 , Mann-Whitney, and t tests. Results 40% of the surgeries were radical and/or staging procedures and 100% underwent open laparotomies. The median length of hospital stay was 2 days. Only 5% required readmission. The median time to readmission was 4 days. Those patients with a longer initial length of hospital stay and higher mean blood loss were more likely to be readmitted ( P Conclusion This management approach resulted in a length of hospital stay of 2 days without increasing morbidity or mortality after laparotomy for suspected gynecologic malignancy.
Does Family Structure Matter? A Domain-Specific Examination of Identity Exploration and Commitment

This exploratory study examines identity exploration and commitment in different domains and how family structure (original/alternative), gender, and age affect these processes in a convenience sample of 388 college students. Results reveal that participants from alternative family structures explore more in the political and gender role domains than do participants from original families. Furthermore, women explore more in the occupational and friendship domains and are more committed in the values and family domains. Younger participants explore less in the gender role domain compared to older ones. Significant interactions reveal that (a) younger women explored the least, and (b) men from alternative families are the least committed in the values domain, compared to all other groups. Findings support the value of exploring the relative impact of family-focused experience on the processes of identity formation and, for the current convenience sample, suggest that growing up in an alternative family stru...
Hay un sesgo de selección en la reparación endovascular de aneurismas rotos

Los datos acumulados sugieren que la reparacion endovascular (RAEV) de la rotura de aneurismas aorticos abdominales (AAAR) da lugar a una disminucion de la mortalidad, pero suscita preocupacion que esto pueda reflejar un sesgo de seleccion. Para examinar esta cuestion revisamos nuestra experiencia global con la rotura de aneurismas tras instaurar un protocolo de actuacion en nuestro hospital. En julio de 2002, instituimos un protocolo definido para los AAAR haciendo hincapie en la RAEV, que incluyo la disponibilidad del dispositivo , preparacion preoperatoria, acceso de 24 h a nuestro quirofano endovascular (endosuite) y la capacidad para obtener imagenes radiologicas en el contexto de una emergencia, al igual que la disponibilidad inmediata de la infraestructura para colocacion de un oclusor endovascular por via braquial Se revisaron las historias clinicas de todos los pacientes con AAAR que llegaron vivos al quirofano desde la institucion de nuestro protocolo. Se revisaron de nuevo las tomografias computarizadas (TC) para evaluar a los candidatos anatomicos potencialmente idoneos. Desde julio de 2002 a mayo de 2006, se trato en nuestro hospital un total de 52 AAAR: 15 AAAR pararrenales, todos tratados mediante reparacion abierta (PR-abierta), y 37 AAAR infrarrenales, 20 tratados mediante reparacion abierta (IR-abierta) y 17 tratados mediante RAEV (IR-RAEV, el 32% de todas las roturas). En los tres grupos las tasas de mortalidad fueron del 47%, 75% y 35% (p global no fue diferente de los valores historicos, y este hecho, junto con la mortalidad sumamente elevada observada en el grupo IR-abierta, sugiere que simplemente seleccionamos a los pacientes con la mayor probabilidad de supervivencia para someterse a RAEV. Tambien parece ser que muchos pacientes que son candidatos desde un punto de vista anatomico a RAEV se someten a una intervencion abierta a causa de su inestabilidad hemodinamica. Si en realidad la RAEV para la rotura disminuye la mortalidad en todos los pacientes, puede ser necesaria una actitud mucho mas agresiva hacia este procedimiento para reducir la tasa de mortalidad global.
UV-cured pultrusion processing of glass-reinforced polymer composites

A novel process was developed to adapt the pultrusion process to utilize radiation polymerization instead of thermal curing. Using UV-light and a methacrylate-based, 3-D-network copolymer matrix, 0.5 mm diameter round quartz-fiber-reinforced-composite profiles were formed at a rate of 1.25 mm per second. Faster rates resulted in partial curing. Materials were produced with various amounts of reinforcement, and evaluated in tension and in three-point bending. Mechanical properties varied linearly with fiber content, approaching the rule of mixtures.
SURFACTANT-ENHANCED ELECTROOSMOTIC DEWATERING OF MINERAL ULTRAFINES

Abstract The rate and extent of electroosmotic dewatering of mineral ultrafines are dependent on the surface charge density which is quantitatively measured by the zeta potential. This research tailors the surface electrical properties of a naturally uncharged ochre (iron oxide) mineral slurry by altering the concentration of potential determining hydroxide ions to facilitate electroosmotic dewatering. The adsorption of hydroxide ions (9 × 10−4 to 9 × 10−3 M) onto the iron oxide surface provides the necessary increase in zeta potential; however, the resulting electrostatic dispersion of the particles severely limits the hydraulic permeability. Subsequent addition of cetyl trimethyl ammonium bromide (5 × 10−4 to 5 × 10−3 M), a cationic surfacant, reflocculates the particles, while maintaining sufficient zeta potential to generate an electroosmotic effect. Hydraulic performance of the treated slurries is characterized by measurement of flow rate data and specific resistance determination. Further characteri...
Spacing and Site Isolation of Amine Groups in 3-Aminopropyl-Grafted Silica Materials: The Role of Protecting Groups

The relative spacing of amines in 3-aminopropylsilyl-grafted silica is studied by solid-state fluorescence spectroscopy of 1-pyrenecarboxylic acid (PCA) and 1-pyrenebutyric acid (PBA) bound to traditionally prepared, deprotected benzyl- or deprotected trityl-spaced aminosilicas. Thermogravimetric analysis and FT-Raman spectroscopy results show evidence that the protected imine can be cleaved to yield the corresponding amine in essentially quantitative yield. The steady-state fluorescence spectroscopic data of either PCA or PBA indicate that the number of amine pairs on the surface separated by a distance of 1 nm or less decreases as the total amine loading decreases. Both the intensity ratio of the excimer band to the monomer band (I470/I384 or Iexc/Imon) and lifetime decay studies of the fluorophore are useful probes of the amine spacing. Separation of amines on the surface can be achieved by either use of a protected synthesis route or through reduction of the concentration of the unprotected 3-aminopro...
Structural Basis for Enzyme I Inhibition by α‑Ketoglutarate

Creating new bacterial strains in which carbon and nitrogen metabolism are uncoupled is potentially very useful for optimizing yields of microbial produced chemicals from renewable carbon sources. However, the mechanisms that balance carbon and nitrogen consumption in bacteria are poorly understood. Recently, α-ketoglutarate (αKG), the carbon substrate for ammonia assimilation, has been observed to inhibit Escherichia coli enzyme I (EI), the first component of the bacterial phosphotransferase system (PTS), thereby providing a direct biochemical link between central carbon and nitrogen metabolism. Here we investigate the EI-αKG interaction by NMR and enzymatic assays. We show that αKG binds with a KD of ∼2.2 mM at the active site of EI, acting as a competitive inhibitor. In addition, we use molecular docking simulations to derive a structural model of the enzyme-inhibitor complex that is fully consistent with NMR and analytical ultracentrifugation data. We expect that the EI-αKG structure presented here will provide a starting point for structure-based design of EI mutants resistant to αKG.
Spectral line intensities in a nonequilibrium nitrogen plasma.

Abstract For given ratios of nonequilibrium ground state number density to equilibrium ground state number density, and given electron temperatures, the relative populations of excited states of atomic nitrogen in a collision-dominated nonequilibrium plasma, consisting of atoms, singly charged ions, and electrons, are calculated by the method of Bates, Kingston, and McWhirter. This method uses Gryzinski's semiclassical cross sections for the collisional excitation of electronic states of an atom. From the resulting populations, the spectral intensities of two prominant visible lines are calculated assuming the plasma to be optically thin for these lines. It is shown that, with the exception of a decaying plasma at temperatures greater than 8000°K, the calculated nonequilibrium intensities disagree with the equilibrium spectral line intensities that would be conventionally employed to determine the temperature of a plasma in equilibrium.
Growth ofTrifolium pratense L. pollen tubes in compatible and incompatible styles of excised pistils.

The excised pistil technique was used to study effects of pollen treatments on self-incompatibility in red clover. Pollen was treated directly with infrared or ultraviolet radiation, and indirectly with chemicals that were applied to the stigmas before pollination. The chemicals (boric acid, calcium nitrate, colchicine, cyclohexamide, gibberellic acid, glycine, and indole butyric acid) were each used at five concentrations. High dosage rates of most treatments inhibited pollen growth in styles that were genetically compatible, but none of the treatments had a specific effect on the self-incompatibility mechanism.
Ultrafast XAFS of transition metal complexes

Ultrafast laser pump-XAFS probe spectra of ironhexacyanide solvated in water have been measured using a laser-driven plasma x-ray source. A new x-ray source driven by a 15-W, 5-kHz laser system has been developed.
Regional anesthesia for hip surgery

Regional anesthesia techniques are important for patients who undergo hip surgery. Although both general and regional anesthesia can be conducted in a safe, effective manner, the ability to provide superior postoperative analgesia, improved patient satisfaction, rapid postoperative recovery, and reduced cost of medical care can be the result of carefully implemented regional anesthesia techniques. Further established advantages of regional anesthesia include a reduction in perioperative blood loss and a lower incidence of perioperative deep venous thrombosis (DVT) formation for patients undergoing total hip arthroplasty or surgical repair of a hip fracture. This article discusses the common types of hip surgery and the regional anesthetic techniques that may be effectively utilized in those surgical settings.
Anoplasty for anal stricture

Twelve patients with anatomic anal stricture were treated with C-anoplasty in the past six years. Anal stricture was caused by previous hemorrhoidectomy in ten, fistulectomy in one, and fissurectomy in one. All patients had had conservative treatment from four to 22 years but failed to respond. Eleven patients obtained satisfactory results from C-anoplasty; one required three anal dilatations postoperatively because of restricture. C-anoplasty is advantageous because it extends the pedicle without compromising vascular supplies; suture-line tension can be controlled by extending the incision; and the size of the graft is easily adjustable to anal size.
Pseudo-Chebyshev spectral method for simulating one-dimensional magnetotelluric responses

Abstract An efficient FORTRAN-77 algorithm based on the Pseudo-Chebyshev Spectral (PCS) method is presented for calculating magnetotelluric (MT) responses of the Earth's one-dimensional (1-D) electrical conductivity structure. The method first represents the unknown solution and its spatial derivatives with a finite degree Chebyshev polynomial at a number of depth points (NDP); then uses the orthogonal and the recurrence properties of the Chebyshev polynomial to set up a linear equation system for these unknowns; and finally, employs an iterative procedure preconditioned with the lowest order of finite difference (FD) to solve the linear system. When the NDP becomes large, the Fast Fourier Transform is implemented to speed the transform between the spectral and physical domains. With these techniques, the PCS method, although requiring at most three and one-half times as much computer time as the lowest order FD method, achieves a more accurate solution when NDP is not greater than 128. Extension of this method to higher dimensions is straightforward, and should be more efficient than the FD method for smooth Earth structures because of the separability of the higher dimensional Fourier transforms.
Unwinding protein complexes in ALTernative telomere maintenance

Telomeres are composed of specialized chromatin that includes DNA repair/recombination proteins, telomere DNA-binding proteins and a number of three dimensional nucleic acid structures including G-quartets and D-loops. A number of studies suggest that the BLM and WRN recQ-like helicases play important roles in recombination-mediated mechanisms of telomere elongation or Alternative Lengthening of Telomeres (ALT), processes that maintain/elongate telomeres in the absence of telomerase. BLM and WRN localize within ALT-associated nuclear bodies in telomerase-negative immortalized cell lines and interact with the telomere-specific proteins POT1, TRF1 and TRF2. Helicase activity is modulated by these interactions. BLM functions in DNA double-strand break repair processes such as non-homologous end joining, homologous recombination-mediated repair, resolution of stalled replication forks and synthesis-dependent strand annealing, although its precise functions at the telomeres are speculative. WRN also functions in DNA replication, recombination and repair, and in addition to its helicase domain, includes an exonuclease domain not found in other recQ-like helicases. The biochemical properties of BLM and WRN are, therefore, important in biological processes other than DNA replication, recombination and repair. In this review, we discuss some previous and recent findings of human rec-Q-like helicases and their role in telomere elongation during ALT processes.
Complete Genome Sequence of the Cellulolytic Thermophile Caldicellulosiruptor obsidiansis OB47T

Caldicellulosiruptor obsidiansis OB47(T) (ATCC BAA-2073, JCM 16842) is an extremely thermophilic, anaerobic bacterium capable of hydrolyzing plant-derived polymers through the expression of multidomain/multifunctional hydrolases. The complete genome sequence reveals a diverse set of carbohydrate-active enzymes and provides further insight into lignocellulosic biomass hydrolysis at high temperatures.
Who engages in health protective behaviors

The concept of health protective behaviors explicitly calls attention to the fact that individuals undertake behaviors they believe are protective of their health whether or not their beliefs correspond to professional medical advice. There are four types of health protective behaviors: life style changes undertaken with and without medical advice, and treatment regimens undertaken with and without medical advice. The present paper, which presents data on three of these four types of health protective behaviors, finds only weak associations between these behaviors and both sociodemographics and general health orientations. The implications of these findings for both health education aimed at changing these behaviors and sociological analysis aimed at understanding these behaviors is discussed.
Flow-diverting stents for the treatment of arterial aneurysms

Background Anatomic factors may limit the application of stent grafts for the treatment of arterial aneurysms. Flow- diverting stents (FDSs) are specially designed to reduce flow velocity in the aneurysm sac and promote thrombosis while maintaining flow in the main artery and branch vessels. FDSs include the Pipeline Embolization Device (ev3, Plymouth, Minn), the SILK Arterial Reconstruction Device (Balt Extrusion, Montmorency, France), and the Cardiatis Multilayer Stent (Cardiatis, Isnes, Belgium). The first two have been mainly used for the treatment of intracranial aneurysms. The aim of this study was to review the current role of FDSs in the treatment of extracranial arterial aneurysms. Methods A systematic electronic health database search was conducted using PubMed, Ovid, Medline, and the Cochrane Database on all accessible published articles through March 2012. An additional search for abstracts presented in international congresses for vascular surgery was also performed. Full-text articles and abstracts were analyzed separately due to the heterogeneity of the data. Results Results of the use of FDSs in arterial aneurysms were reported in 12 full-text articles including 35 patients (26 men, age 65.4) with 38 aneurysms. The aneurysms were located in the hepatic (n = 12), splenic (n = 6), renal (n = 5), celiac (n = 4), superior mesenteric (n = 3), subclavian (n = 2), gastroduodenal (n = 1), and popliteal arteries (n = 1) and in the descending thoracic (n = 1), suprarenal (n = 1) and infrarenal aorta (n = 2). The 30-day mortality was 5.7% (2 of 35 patients). Three stent thromboses occurred (8.3%), none of them with clinical consequences. Thirty patients with 33 aneurysms and patent FDSs were monitored for an average of 9.2 months. Thrombosis occurred in 90.6%, and volume reduction was observed in 81% of the aneurysms. No branch vessel occlusion occurred. Twelve abstracts were identified, including 133 patients (mean age, 64.7 years). They included 62 peripheral, 28 visceral, and 43 abdominal and thoracoabdominal aneurysms. The Cardiatis Multilayer Stent was used in all cases. Thrombosis was achieved in all but two peripheral and visceral aneurysms. Volume reduction was observed in 82.7%, and no branch vessel occlusion occurred. In aortic aneurysms, better results regarding aneurysm thrombosis, reduction of the volume, and patency of collateral branches were reported at 12 months rather than at 6 months postoperatively. No aneurysm rupture has yet been described. Conclusions Initial clinical experience with the use of FDSs in the treatment of visceral and peripheral aneurysms yielded satisfactory results in technical success, aneurysm thrombosis and shrinkage, and in patency of branch vessels. The results in aortic aneurysms are still under investigation. No aneurysm rupture has yet been described. There is a significant incidence of FDS thrombosis. Volume reduction of the aneurysm is a clearer evidence of the clinical success after treatment with FDSs than aneurysm thrombosis.
CONVERSION OF CHOLESTEROL TO PROGESTERONE BY CORPUS LUTEUM SLICES.

The conversion of cholesterol-7-3H to progesterone was studied in slices of bovine corpus luteum by measuring both the total amount of progesterone synthesized and the radioactivity in the final product derived from cholesterol-7-3H. The addition of luteinizing hormone to the incubating slices caused an increase in the amount of progesterone synthesized but only a slight increase in the conversion of radioactive cholesterol. The addition of NADP +glucose-6-phosphate, on the other hand, increased both the amount of progesterone and, to a greater extent, the conversion of added cholesterol-7-3H to progesterone. Neither added LH nor added NADP -fglucose-6-P influenced the penetration of the radioactive cholesterol into the slices. It was concluded that NADPH increases progesterone synthesis primarily through its action on the transformation of cholesterol, whereas LH affects the transformation of cholesterol to a slight extent only and acts mainly on precursors prior to cholesterol in the biosynthetic pathwa...
Historical and recent fire regimes in Piñon-Juniper woodlands on Mesa Verde, Colorado, USA

Abstract The fire history of Pinon–Juniper ( Pinus edulis – Juniperus osteosperma ) woodlands in much of the southwestern United States is poorly understood, and as a result, fire management decisions are being made without a rigorous ecological underpinning. We investigated the historic fire regimes in Pinon–Juniper woodlands on the Mesa Verde cuesta utilizing stand and age structures. All Pinon trees in eight stands were aged and stand age was extrapolated to the surrounding landscapes using digital imagery, creating a time-since-fire map of the 1995 landscape. Six sampled stands were over 400 years, while two were between 200 and 300 years. Stand-replacing fire with a rotation of 400 years or longer characterized this Pinon–Juniper landscape before 1995; low-severity surface fires apparently have never been an important component of the fire regime in Mesa Verde. Superposed epoch analysis revealed that large fires occur following significantly low precipitation in May or in the winter (October–March) preceding a summer fire season. Since the mid-1990’s, a severe drought has characterized climate in this region, but the recent drought is similar to previous drought periods since 1950. A combination of canopy fuel build-up during two wet decades before 1995 and the current drought conditions has resulted in unprecedented fire activity (six large wildfires between 1996 and 2003) when compared with the reference period 1700–1900. We may be witnessing a unique period in the ecological history of the southwest, a period when vegetation patterns are being altered over extensive areas within a very short time. If the current drought continues, we ultimately may lose much of the old-growth Pinon–Juniper woodland in the southwest. We emphasize however, that these changes are not due to fire suppression or other direct human intervention but rather result from natural ecological responses to climatic variability. Therefore, our data provide no ecological justification for aggressive management activities such as mechanical fuel reduction or prescribed burning, except in the immediate vicinity of vulnerable cultural resources.
UpLib: a universal personal digital library system

We describe the design and use of a personal digital library system, UpLib. The system consists of a full-text indexed repository accessed through an active agent via a Web interface. It is suitable for personal collections comprising tens of thousands of documents (including papers, books, photos, receipts, email, etc.), and provides for ease of document entry and access as well as high levels of security and privacy. Unlike many other systems of the sort, user access to the document collection is assured even if the UpLib system is unavailable. It is "universal" in the sense that documents are canonically represented as projections into the text and image domains, and uses a predominantly visual user interface based on page images. UpLib can thus handle any document format which can be rendered as pages. Provision is made for alternative representations existing alongside the text-domain and image-domain representation, either stored or generated on demand. The system is highly extensible through user scripting, and is intended to be used as a platform for further work in document engineering. UpLib is assembled largely from open-source components (the current exception being the OCR engine, which is proprietary).
Strategies And Structures For Diversification

This paper describes a study of corporate technological staff size in 21 large, diversified firms. The marked bimodality of the resulting data suggests that sample firms are avoiding intermediate p...