cssi/SciSciGPT-SciSciNet huggingface dataset:
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) induces plasminogen activator inhibitor-1 through an aryl hydrocarbon receptor-mediated pathway in mouse hepatoma cell lines.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a ubiquitous environmental pollutant, elicits a variety of toxicities and is a well-known carcinogen. TCDD alters the expression of many genes including CYP1A1/2, CYP1B1, glutathione S-transferase Ya, aldehyde-3-dehydrogenase, NAD(P)H:quinone oxidoreductase, transforming growth factor (TGF)-α and TGF-β. The present study was aimed at characterization of TCDD to induce plasminogen activator inhibitor-1 (PAI-1) in mouse hepatoma cell lines. A Hepa1c1c7 wild-type cell [H1(wt)], an aryl hydrocarbon receptor (AhR)-deficient mutant [H1(AhR–)] and an AhR nuclear translocator (Arnt)-deficient mutant [H1(Arnt–)] were used for this study. TCDD induced PAI-1 in H1(wt) cells, but not in H1(AhR–) and H1(Arnt–) mutants, indicating a functional role of the AhR-Arnt complex in this effect. Cycloheximide (CHX) treatment resulted in increased PAI-1 mRNA induction, indicating that this response to TCDD is a direct effect on transcription and not a secondary effect mediated by other TCDD-induced proteins. Transfection with PAI-1 promoter led to increased PAI-1 promoter activity in H1(wt) cells treated with TCDD, but no such effect occurred in H1(AhR–) or H1(Arnt–) cells, implying involvement of the AhR and Arnt. In addition, α-naphthoflavone and phenanthroline, two AhR antagonists, each blocked the enhancing effect of TCDD on PAI-1 promoter-coupled luciferase activity in H1(wt) cells. PAI-1 promoter deletion analysis indicated that TCDD-induced PAI-1 transcription was distinctly different from TGF-β-dependent PAI-1 transcription, particularly in the region between –161 to +73. In summary, TCDD induced the PAI-1 gene directly via an AhR- and Arnt-dependent mechanism, which was distinctly different from TGF-β-driven PAI-1 transcription.
Nipple-sparing mastectomy update: one hundred forty-nine procedures and clinical outcomes.

Objectives To describe our experience with patients who underwent the nipple-sparing mastectomy procedure developed and standardized at our institution and to report clinical outcomes for those patients with a breast cancer diagnosis. Design Prospective study for consecutive nipple-sparing mastectomy procedures. Setting Multidisciplinary breast center at a large tertiary care facility. Patients One hundred ten consecutive patients underwent nipple-sparing mastectomy between July 2001 and June 2007. Intervention Nipple-sparing mastectomy was offered to carefully screened patients; the nipple-areola tissue was cored and sent for histologic frozen-section analysis intraoperatively. Main Outcome Measures Assessment of nipple-areola cored tissue for neoplastic involvement; postoperative stability of retained nipple-areola complex; and clinical outcomes. Results Data were available for 149 nipple-sparing mastectomies performed on 110 patients. No procedure performed for prevention had neoplastic involvement of the cored nipple-areola tissue, while 9 procedures performed for breast cancer treatment were found to have neoplastic involvement. Postoperatively, 2 patients had partial loss of the nipple-areola complex due to sloughing and a third patient developed an infection that required surgical removal of the nipple-areola complex. Among patients with breast cancer, none with ductal carcinoma in situ has developed a recurrence, while 4 patients with infiltrating breast cancer have, including 2 patients with distant metastases only, a third with a chest wall recurrence, and a fourth with an axillary recurrence. Conclusion A low incidence of neoplastic involvement of the nipple-areola cored tissue leads to successful completion of nipple-sparing mastectomy for most patients.
A numerical method for the thermodynamic properties of monatomic ionized gases

A numerical method for the direct computation of the particle densities, mass density, enthalpy and specific heat at constant pressure of a monatomic ionized gas in thermodynamic equilibrium is presented. This method permits calculation of the thermodynamic properties without iteration or numerical differentiation of any of the formulae.
Stimulation of Type I Collagen Transcription in Human Skin Fibroblasts by TGF-β: Involvement of Smad 3

Transforming growth factor-β (TGF-β) stimulates the transcription of the α2(I) procollagen gene (COL1A2). The intracellular mediators involved in this response remain poorly understood. In this study, we demonstrate that primary human skin fibroblasts express Smads, a novel family of signaling molecules, in vitro in the absence of TGF-β. The levels of Smad 7 mRNA was rapidly and transiently increased by TGF-β. Transient overexpression of Smad 3 and Smad 4, but not Smad 1 or Smad 2, caused trans -activation of a CAT reporter gene driven by a 772 bp segment of the human COL1A2 promoter containing putative TGF-β response elements. Smad stimulation of promoter activity was ligand independent, but was further enhanced by TGF-β. Overexpression of a phosphorylation-deficient Smad 3 mutant or wild-type Smad 7, which lacks the carboxy-terminal phosphorylation motif, specifically inhibited TGF-β-induced activation of COL1A2 promoter. A CAGACA sequence shown to be a functional Smad-binding element in the plasminogen activator inhibitor-1 gene promoter was found within the TGF-β-response region of the proximal COL1A2 promoter. Gel mobility shift assays showed protein phosphorylation-dependent binding activity in fibroblast nuclear extracts specific for this sequence; TGF-β treatment strongly stimulated the formation of this DNA-protein complex. Smad was identified as a component of the CAGACA-binding transcription complex in TGF-β-treated fibroblasts by antibody supershifting. These results demonstrate that (i) Smad 3 transmits TGF-β signals from the receptor to the COL1A2 promoter in human fibroblasts, and is likely to play an important role in stimulation of COL1A2 promoter activity elicited by TGF-β; (ii) in fibroblasts, Smads appear to function as inducible DNA-binding transcription factors; and (iii) Smad 7 may be involved in autocrine negative feedback in the regulation of COL1A2 promoter activity by TGF-β.
Role of cytoplasmic ATP in the restoration and maintenance of a membrane permeability barrier in transformed mammalian cells

Addition of ATP to medium surrounding intact, transformed 3T3 cells activates the formation of aqueous channels in the plasma membrane. This results in efflux of nucleotide pools and ions and entry into the cytosol of charged, phosphorylated species. In such permeabilized cells, glycolysis is totally dependent on the external addition of glucose, inorganic phosphate, ADP, K+, Mg2+ and NAD+ which restore lactic acid formation to levels found in untreated cells. As expected, such reconstitution of glycolytic activity is found to restore intracellular ATP levels. This is accompanied by sealing of the membrane channels so that efflux of nucleotide pools ceases. Pyruvate, a substrate for mitochondrial ATP synthesis, when provided along with ADP and inorganic phosphate also produces sealing of the membrane channels. On the other hand, reactivation of pentose phosphate shunt activity, which does not lead to ATP synthesis, does not induce restoration of the membrane permeability barrier. Furthermore, compounds which lower the internal ATP pool prevent sealing, and also render the plasma membrane more sensitive to external ATP (Roxengurt and Heppel, 1979). Sealing of aqueous channels following restoration of the internal ATP pool is associated with phosphorylation of the inner membrane surface, and is unaffected by inhibitors of protein synthesis, microfilament or microtubular assembly. These results indicate the probable role of intracellular ATP in the restoration and/or maintenance of an active membrane barrier against efflux of small molecules and ions in transformed 3T3 cells.
Theoretical π-π* absorption, circular dichroic, and linear dichroic spectra of collagen triple helices

Absorption, CD, and LD spectra of the π-π* transition near 200 nm are calculated for poly(Gly-X-Y) (X,Y = Gly, Ala, Pro) in four conformations proposed for collagen like triple helices in the recent literature. A dipole interaction model is used with the same optical paramenters as in previous studies of polypeptide spectra. The CD spectra are sensitive to backbone structure and amino acid composition, although the experimentally observed negative peak near 200 nm is a general feature of most the calculated spectra. Interchain interactions significantly affect the CD spectra in most cases. Calculations for (Gly-Pro-Ala)3 and (Gly-Ala-Pro)3 in the triple helical structure of Fraser, MacRae, and Suzuki [(1979) J. Mol. Biol.129, 463–481] show absorption, CD, and LD spectra in fairly good agreement with experiment. The characteristics of the π-π* normal modes responsible for the calculated spectra are compared with those of the component bands resolved from the experimental spectra of collagen by Mandel and Holzwarth [(1973) Biopolymers12, 655–674].
Microwave Sounding Units and Global Warming

A recent work of Spencer and Christy (1990) on precise monitoring of global temperature trends from satellites is critically examined. It is tentatively concluded in the present comment that remote sensing using satellite microwave radiometers can in fact provide a means for the monitoring of troposphere-averaged air temperature. However, for this to be successful more than one decade of data will be required to overcome the apparent inherent variability of global average air temperature. It is argued that the data set reported by Spencer and Christy should be subjected to careful review before it is interpreted as evidence of the presence or absence of global warming. In a reply, Christy provides specific responses to the commenters' objections.
Structure and Thermomechanical Properties of Systems Based on Epoxy Polymer, Metal Oxides, and Polyaniline

We study the structure and thermomechanical properties of systems based on epoxy polymer, metal oxides, and polyaniline. It is shown that iron oxide in a mixture with polyaniline begins to reveal its crystalline structure in the composite for a fairly low concentration level (1.0 vol.%) unlike aluminum oxide, which does not reveal its structure even for its high contents. The investigations reveal a strong dependence of the microheterogeneous structure of composites on the type of metal atoms in oxides. By the method of thermomechanical analysis, we show that the composites based on the epoxy polymer and a mixture of polyaniline with one of the metal oxides ( Al2O3 or Fe2O3) are characterized by the abnormal expandability (α1 = 25%).
In vivo rates of tyrosine and tryptophan hydroxylation in regions of rat brain at four times during the light-dark cycle.

The in vivo rates of tyrosine and tryptophan hydroxylation were studied in three regions of young adult rat brains at 4 times during the light-dark cycle. The procedure utilized was to analyze the accumulation of Dopa and 5-HTP after injection of a centrally effective L-amino acid decarboxylase inhibitor, NSD 1015. Monoamine levels were also determined in all control animals and some treated animals. The rate of tyrosine hydroxylation in the telencephalon was significantly higher 7 hrs after dark onset than at the other three times tested. Smaller variations in tyrosine and tryptophan hydroxylation rates as a function of time of day were also observed. 5-HT levels were significantly higher during the light phase than the dark in the telencephalon with the same trend occurring in the diencephalon and brainstem. NA was stable in the telencephalon but reached lower levels in the light and higher levels in the dark in the other two regions. In the telencephalon DA reached high levels early in the light and in the dark phases, showing a biphasic variation. Of particular interest was the apparent lack of correlation between cyclic changes in the monoamine levels and the changes in hydroxylation rates. Rates of hydroxylation can be considered indicative of rates of monoamine synthesis. This observation is discussed in relation to feedback and other mechanisms regulating synthesis and release of monoamines.
An Object-Based Classification Approach in Mapping Tree Mortality Using High Spatial Resolution Imagery

In California, a newly discovered virulent pathogen (Phytophthora ramorum) has killed thousands of trees, including tanoak (Lithocarpus densiflorus), coast live oak (Quercus agrifolia), and black oak (Quercus kelloggii). Mapping the distribution of overstory mortality associated with the pathogen is an important part of disease management. In this study, we developed an object-based approach, including an image segmentation process and a knowledge-based classifier, to detect individual tree mortality in imagery of 1 m spatial resolution. The combined seg- mentation and classification methods provided an easy and intuitive way to incorpo- rate human knowledge into the classification process. The object-based approach significantly outperformed a pixel-based maximum likelihood classification method in mapping the tree mortality on high-spatial-resolution multispectral imagery.
Currency devaluation, aggregate output, and the long run: an empirical study

Abstract This paper estimates the effect of currency devaluation on the aggregate output level in six Asian countries using a unique methodology developed by Wickens et al. (1988; Economic Journal 189–205). The estimated results suggest that devaluation, in general, is neutral in the long run. In some cases it even can have a contractionary effect.
Gluten detection in foods available in the United States - a market survey.

Abstract Many gluten-free (GF) food choices are now available in supermarkets. However, the unintentional presence of gluten in these foods poses a serious health risk to wheat-allergic and celiac patients. Different GF labelled foods (275) and non-GF labelled foods, without wheat/rye/barley on the ingredient label (186), were analysed for gluten content by two different enzyme linked immunosorbent assay (ELISA) kits. Considering the gluten threshold of 20 ppm, GF labelled foods had 98.9% GF labelling compliance with 1.1% (3 out of 275) of foods being mislabelled/misbranded. Among the non-GF labelled foods, 19.4% (36 out of 186) of foods had >20 ppm of gluten, as measured by at least one ELISA kit, of which 19 foods had >100 ppm of gluten. The presence of oats in non-GF labelled foods was strongly correlated with a positive ELISA result. Gluten was also found in a significant number of foods with gluten/wheat-related advisory warnings.
Differences in the three-dimensional typing forces between short and long travel keyboards

Keyboards with shorter key travel are becoming widespread yet it is unknown whether there are any biomechanical differences in the typing forces when using these keyboards. If one keyboard promotes typing with more force, this may increase the risk for developing an upper extremity disorder. A total of 17 subjects typed on two short travel keyboards (<2.5 mm) and one long travel keyboard (4.0 mm). The magnitude and angle of the typing forces were measured in the x-, y- and z-axes using a thin, threedimensional force platform. The aim of this study was to determine whether there were differences between the short and long travel keyboards in the magnitude and direction of the typing forces and the keystroke durations. In addition we wanted to determine whether there were typing force differences between key rows, hands, and fingers. Keyboards with shorter key travel resulted in less extreme angles and smaller magnitudes for forces applied in the x and y directions. Shorter travel distances were associated with smaller peak and mean vector sum forces and shorter keystroke durations. Although these results indicate keyboards with shorter key travel affect typing biomechanics, it is uncertain whether the small differences in keystroke durations and applied typing forces are physiologically meaningful and would reduce a computer user’s risk for developing an upper extremity musculoskeletal disorder.
Darryl E. Metzger Memorial Session Paper: Surface Heat Transfer From a Three-Pass Blade Cooling Passage Simulator

Using an analogous mass transfer system based on naphthalene sublimation, the present research focuses on investigating the local heat transfer characteristics from three-pass smooth and turbulated blade cooling passages. To simulate the actual passage geometry, the test model is incorporated with trapezoidal cross sections including variable passage sizes. Measured local mass transfer results reveal strong evidence of velocity redistribution over the trapezoidal flow area. Elevated mass transfer always exists in the vicinity of a sharp turn. However, in the present study, one of the most notable mass transfer increases is perceived in the third pass, downstream to the second turn, where the flow area is reduced severely. Overall, the combined effects of the three-pass and two sharp turns virtually double the mass transfer as compared to its straight counterpart with fully developed, turbulent flow. With a pitch-to-height ratio equal to 10 and 90 deg orientation, the rib turbulators produce approximately an additional 30 percent of overall mass transfer enhancement in comparison to the smooth case. Locally, rib-induced enhancement varies with different surfaces and passes. The greatest enhancement lies on the first pass, about 40 percent; the other two passes are comparable, less than 20 percent.
Protein evolution: The enzyme perfected

The origin of the flavonoid biosynthetic enzyme chalcone isomerase has remained a mystery. A combination of phylogenetic analysis, crystallography, biochemistry and genetics has uncovered how a stereospecific chalcone isomerase could have evolved from a nonenzymatic ancestral gene.
Vaccination in children with cancer: a debate

Children with malignancy present an important alteration of the immune system functionality caused by the illness itself and by the therapy they undergo. Therefore, they are at high risk of contracting vaccine-preventable diseases and of developing important complications. Vaccinations represent valid devices against these infections but this condition involves two main problems: are vaccines safe in these patients? Are vaccines effective in these patients? The aim of this review is to discuss the principles of vaccination management in children with cancer.
Variable Acorn Crops: Responses of White-Tailed Deer and other Mast Consumers

We examined movements and behavior of female white-tailed deer ( Odocoileus virginianus ) relative to the acorn mast-fall from 1986 through 1989 in a mature deciduous forest in Front Royal, Virginia. Ten white-tailed deer with radiotransmitters increased their home range to incorporate acorn-producing areas during mast-fall. Consumption of acorns by deer constituted ca. 50% of foraging time during peak mast-fall; average consumption rate was 0.75 acorns/min searching. Although the number of acorns eaten by deer was correlated with mast-fall, a prolonged time was spent searching for acorns after mast-fall. Deer consumed 70% of marked acorns placed out during mast-fall, while medium-sized animals (e.g., Tamias striatus, Sciurus niger, Sciurus carolinensis ) consumed 61% of acorns placed out later in autumn. We hypothesize that high densities of deer may limit populations of more mast-dependent species, particularly at low acorn-crop densities.
Simplification of games in extensive form

Thevon Neumann-Morgenstern normal form of a game is conceptually and theoretically useful, but in practice leads to enormous matrix games. We discuss new methods of simplifying games in extensive form that should be useful for solving actual games. The first method is that of partially normalizing the game at an information set and, if dominations are found, making local “negative” decisions not to choose certain alternatives at the information set. Coupled with this idea is the reduction operation which eliminates parts of the game tree. These methods are shown to be powerful enough to eliminate all dominations in the strategy matrix, where we consider domination in three senses.
Protovis: A Graphical Toolkit for Visualization

Despite myriad tools for visualizing data, there remains a gap between the notational efficiency of high-level visualization systems and the expressiveness and accessibility of low-level graphical systems. Powerful visualization systems may be inflexible or impose abstractions foreign to visual thinking, while graphical systems such as rendering APIs and vector-based drawing programs are tedious for complex work. We argue that an easy-to-use graphical system tailored for visualization is needed. In response, we contribute Protovis, an extensible toolkit for constructing visualizations by composing simple graphical primitives. In Protovis, designers specify visualizations as a hierarchy of marks with visual properties defined as functions of data. This representation achieves a level of expressiveness comparable to low-level graphics systems, while improving efficiency - the effort required to specify a visualization - and accessibility - the effort required to learn and modify the representation. We substantiate this claim through a diverse collection of examples and comparative analysis with popular visualization tools.
The Conditional Relationship between Inequality and Development

In recent years political scientists and economists have spent considerable efforts investigating the impact of income inequality both on political institutions and social conflict (Boix 2003, 2008; Acemoglu and Robinson 2006; Geddes 2007) and on growth and development (Atkinson and Bourguignon 2000). In this article I focus on the latter question: I discuss the extent to which (that is, the conditions under which) inequality may hinder economic growth. I do so by moving away from the current literature, which models the relationship between development and inequality in a linear fashion—with the latter unconditionally distorting (or boosting) the incentives to invest and therefore reducing (or increasing) the rate of growth. Instead, I claim that the potential correlation between inequality and development will be always conditional on the (mostly political and institutional) causes that generate the existing income distribution to start with. Hence it is not surprising to find instances in which growth and (mostly temporary) inequality come hand in hand as well as other periods and countries where there is both high and persistent inequality jointly with economic stagnation.
Approximating Fourier transformation of orbital integrals

In this paper, we are concerned with orbital integrals on a class C of real reductive Lie groups with non-compact Iwasawa K-component. The class C contains all connected semisimple Lie groups with infinite center. We establish that any given orbital integral over general orbits with compactly supported continuous functions for a group G in C is convergent. Moreover, it is essentially the limit of corresponding orbital integrals for its quotient groups in Harish-Chandra's class. Thus the study of orbital integrals for groups in class C reduces to those of Harish-Chandra's class. The abstract theory for this limiting technique is developed in the general context of locally compact groups and linear functionals arising from orbital integrals. We point out that the abstract theory can be modified easily to include weighted orbital integrals as well. As an application of this limiting technique, we deduce the explicit Plancherel formula for any group in class C.
Congenital Disorders of Platelet Function: Disorders of Signal Transduction and Secretion

Congenital defects in platelet function are associated with bleeding manifestations of variable intensity and arise by diverse mechanisms. Defects in platelet-vessel wall interaction (disorders of adhesion) may arise because of qualitative or quantitative abnormalities in plasma von Willebrand factor (von Willebrand disease) or in platelet glycoprotein Ib, the binding site on platelets for von Willebrand factor (Bernard-Soulier syndrome). Disorders characterized by abnormal platelet-platelet interaction (disorders of aggregation) arise because of absence of plasma fibrinogen (congenital afibrinogenemia) or because of qualitative or quantitative abnormalities in platelet glycoprotein IIb-IIIa complex (Glanzmann's thrombasthenia). Patients with abnormalities in platelet secretion and signal transduction are a heterogeneous group characterized by impaired aggregation responses and secretion of granule contents. A small proportion of these patients have deficiency of granule stores (storage pool deficiency [SPD]) or impaired production of thromboxane A2; in most, the mechanisms underlying the platelet dysfunction are unknown. Evidence is accumulating that at least some patients have abnormalities in early signal transduction events. Abnormalities in phospholipase C activation, G-protein activation, and other events (eg, protein phosphorylation) have been documented. Platelets play a major role in blood coagulation, and in Scott syndrome, there is an abnormality in platelet contribution to the mechanisms leading to thrombin generation. In most patients with inherited platelet dysfunction, the underlying mechanisms remain to be delineated. Future studies of these patients should yield valuable new information on normal platelet mechanisms.
Optimizing Space Exploration

Both robotic and human missions into space are necessary for an effective program of space exploration. For the nations that have sent humans into space (Russia, China, and the United States) the competition for limited budgets between human and robotic exploratory strategies is inevitable. Yet, the two strategies are complimentary and mutually supportive. Robotic missions are much cheaper than human missions. A major breakthrough in cost are so-called CubeSats—small spacecrafts generally of 10 × 10 × 10 cm dimensions with scaled-down miniaturized payloads (Loff and Dunbar 2017). Robotic missions will remain the best if not only way to investigate difficult to reach planetary bodies and to explore hostile environments such as the radiation-intense surfaces of the Jovian moons. Also, any initial mission to a planetary body will have to be robotic to understand the planetary environments, avoid unnecessary risks, and conduct space exploration in a cost-efficient way. However, eventually human missions are warranted on philosophical grounds and necessary on practical grounds.
Receiver Design for Mobile OFDM with Application to DVB-H

In mobile reception, orthogonal frequency division multiplexing (OFDM) may experience significant inter-carrier interference (ICI) which introduces an error floor proportional to the normalized Doppler frequency. To mitigate the effect of ICI, many schemes have been proposed but they are computationally complex for systems using large OFDM symbol length such as digital video broadcasting system for handheld (DVB-H). In this paper, we propose a low-complexity ICI suppression and channel estimation scheme for DVB-H systems. The proposed scheme is applied to a typical DVB-H system. Simulation results demonstrate that the proposed scheme is robust to mobility and can be employed efficiently in a DVB-H system. Comparison of DVB-H system with OFDM modulation and single carrier modulation (SC) employing frequency domain equalization (FDE) is investigated. Simulation results show the superiority of the SC to OFDM modulation for DVB-H systems and for the simulated scenarios.
The use of a xylosylated plant glycoprotein as an internal standard accounting for N-linked glycan cleavage and sample preparation variability

RATIONALE Traditionally, free oligosaccharide internal standards are used to account for variability in glycan relative quantification experiments by mass spectrometry. However, a more suitable internal standard would be a glycoprotein, which could also control for enzymatic cleavage efficiency, allowing for more accurate quantitative experiments. METHODS Hydrophobic, hydrazide N-linked glycan reagents (both native and stable-isotope labeled) are used to derivatize and differentially label N-linked glycan samples for relative quantification, and the samples are analyzed by a reversed-phase liquid chromatography chip system coupled online to a Q-Exactive mass spectrometer. The inclusion of two internal standards, maltoheptaose (previously used) and horseradish peroxidase (HRP) (novel), is studied to demonstrate the effectiveness of using a glycoprotein as an internal standard in glycan relative quantification experiments. RESULTS HRP is a glycoprotein containing a xylosylated N-linked glycan, which is unique from mammalian N-linked glycans. Thus, the internal standard xylosylated glycan could be detected without interference to the sample. Additionally, it was shown that differences in cleavage efficiency can be detected by monitoring the HRP glycan. In a sample where cleavage efficiency variation is minimal, the HRP glycan performs as well as maltoheptaose. CONCLUSIONS Because the HRP glycan performs as well as maltoheptaose but is also capable of correcting and accounting for cleavage variability, it is a more versatile internal standard and will be used in all subsequent biological studies. Because of the possible lot-to-lot variation of an enzyme, differences in biological matrix, and variable enzyme activity over time, it is a necessity to account for glycan cleavage variability in glycan relative quantification experiments. Copyright © 2013 John Wiley & Sons, Ltd.
Subharmonic oscillations and spatial sweeping of isodiffracting ultrashort pulses

Summary form only given.We present a family of closed-form analytical solutions of Hermite-Gaussian pulses which are exact solutions of the paraxial wave equation. These solutions describe isodiffacting ultrashort pulses with higher-order transverse spatial modes. They can be used to model higher-order ultrashort pulses generated by mode locking of both longitudinal and transverse modes in laser cavities. Our solutions show that a total mode lock of TEM/sub 00/ and TEM/sub 01/ transverse spatial modes leads to subharmonic oscillations of the output pulse intensities and a spatial sweeping of femtosecond laser pulses.
Activation of protein kinase C by arachidonic acid selectively enhances the phosphorylation of GAP-43 in nerve terminal membranes

Arachidonic acid (AA), a cis-unsaturated fatty acid that activates certain subspecies of protein kinase C (PKC), has been proposed to act as a retrograde messenger in modifying the efficacy of synapses during long-term potentiation (LTP). One prominent PKC substrate of the nerve terminal membrane, GAP-43 (F1, B-50, neuromodulin), shows an increase in phosphorylation that correlates with the persistence of LTP. The present study investigated whether AA might exert its effects on presynaptic endings by modulating the phosphorylation of GAP-43 and other membrane-bound proteins. Using synaptosomal membranes from the rat cerebrocortex, in which in vivo relationships between protein kinases and their native substrates are likely to be preserved, we found that in the absence of Ca2+, AA exerted a modest effect on the phosphorylation of GAP-43 and several other proteins; however, when AA was applied in conjunction with Ca2+, GAP-43 showed a particularly striking response: at Ca2+ levels likely to exist at the nerve terminal membrane during synaptic activity (10(-7) to 10(-5) M), AA (50 microM) increased the sensitivity of GAP-43 phosphorylation to Ca2+ by an order of magnitude, and increased its maximal level of phosphorylation by 50%. At resting Ca2+ levels, AA potentiated the stimulation in GAP-43 phosphorylation produced by 4 beta-phorbol 12,13-dibutyrate, a diacylglycerol (DAG) analog. The stimulatory effect of AA and its synergistic interaction with Ca2+ were found to be mediated by PKC, since they were blocked by a specific peptide inhibitor of PKC, [Ala25]PKC(19–31), but were unaffected by an inhibitor of protein phosphatase activity or by scavengers of free radicals. Since GAP-43 has been implicated in the development and plasticity of synaptic relationships, the synergistic effects of AA and the intracellular signals Ca2+ and DAG on the phosphorylation of GAP-43 may serve as an AND gate to modify presynaptic function and/or structure in response to coincident pre- and postsynaptic activity.
Coronary heart disease and depression: a review of recent mechanistic research.

Objective:Both behavioural and physiological factors have been proposed as mechanisms that may explain the negative effect of depression on coronary heart disease (CHD). Our aim is to review some o...
DISTANCES, ASSUMPTIONS AND SOCIAL WASPS

The use of distance data in phylogenetic inference retains adherents in molecular systematics, despite the well-established cladistic critique of distances. Molecular distance matrices have been supposed to measure evolutionary divergence; how- ever, trees based upon analyses of such matrices are generally uninterpretable as doing so-under realistic conditions (Farris, 1981, 1985, 1986). In addition, con- version of character data (for example, molecular sequences) to distances discards information (e.g. Farris, 1981). Adherents of distances have usually defended the approach by invoking restrictive assumptions (for example, additivity in expecta- tion, so that the distances may be interpreted as statistical estimates of actual evolu- tionary divergence; Felsenstein, 1984, 1986). It has also been claimed that conversion of character data to distances may be preferable under certain circumstances (Swofford and Olsen, 1990: 422, 425), because: (1) sequences are not intuitively meaningful: (2) p resuppositions about evolutionary processes can be invoked to estimate unseen events (i.e. correct for non-additivity); and (3) numerous methods for distance analyses exist. A superficially more critical “reason” for preferring distances is the argument that parsimony uses only a small fraction of the data, by which is meant the informative characters (e.g. Li and Graur, 1991: 114). Redolent as this argument is of syncretist “criticism” of cladistic classification, it is actually based upon simulations “demonstrating” that parsimony may give incorrect results, relative to distance methods predicated upon the simulated conditions. That is to say, the argument is a conclusion following from the assumptions of the simula- tions All of these defenses of distances are thus alike, in relying upon a p%ri assumptions about evolutionary processes. But which assumptions should be made? And suppose that the assumptions are violated-how may this be determined? Most studies using distance analyses do not consider these questions at all. Examination of the assumptions of a given distance analysis is instructive, for the data themselves frequently provide evidence that the assumptions are violated. The analy- sis is then internally contradictory, a point which is emphasized when the results are contrasted with the results from a distance analysis that is not predicated on the same assumptions. Such cases do not only support the preference for character analysis over distances, they argue against a prioti assumptions in phylogenetic inference in general. I will illustrate this with an example from a recent study on social wasps.
Cloning, expression, purification and preliminary X-ray crystallographic studies of Escherichia coli Hsp100 ClpB nucleotide-binding domain 1 (NBD1).

Escherichia coli Hsp100 ClpB plays critical roles in multi-chaperone systems in cell physiology. After being activated by protein or peptide binding, ClpB disaggregates denatured polypeptides by employing ATP hydrolysis and allows other molecular chaperones such as Hsp70 DnaK and Hsp40 DnaJ to refold the non-native polypeptides. ClpB contains two nucleotide-binding domains with Walker A and B motifs within their primary sequences. Therefore, ClpB can be classified as a member of the large ATPase family known as ATPases associated with various cellular activities (AAAs). The mechanisms by which the ClpB acts as a molecular chaperone to disaggregate denatured polypeptides are unknown. To investigate how the nucleotide-binding domain participates in ClpB chaperone activity, we have cloned and crystallized ClpB nucleotide-binding domain 1 (NBD1). The ClpB NBD1 crystals diffract to 1.80 A using a synchrotron X-ray source and belong to the space group P212121, with unit-cell parameters a = 38.41, b = 65.48, c = 79.13 A. Structure determination by the MAD method is under way.
Strategic manipulations for associative memory and the role of verbal processing abilities in schizophrenia.

Individuals with schizophrenia demonstrate episodic memory (EM) deficits and abnormal EM-related brain activity. Experimental encoding manipulations significantly benefit memory performance in schizophrenia, suggesting that a strategic processing deficit may contribute to memory impairment. However, few studies have investigated the combined effects of encoding and retrieval strategies on EM in schizophrenia. The current study examined the impact of encoding and retrieval strategies on associative memory and brain activity in schizophrenia. We also assessed the role of verbal processing ability in response to strategic memory interventions in schizophrenia. Behavioral and functional neuroimaging data were collected from 23 participants with schizophrenia and 24 comparison subjects while performing associative memory encoding and recall tasks. Behaviorally, both schizophrenia participants and controls benefited from memory strategies and showed significant associations between verbal processing ability and recall. Additionally, among schizophrenia participants, encoding strategy use was associated with enhanced brain activity in multiple brain areas. Schizophrenia participants also demonstrated significant associations between verbal processing ability and encodingrelated brain activity in prefrontal cortex. Findings suggest that memory performance and brain activity in schizophrenia can be enhanced via strategic manipulations, and individual differences in cognitive abilities in schizophrenia can affect behavioral and neurobiological responses to strategic memory interventions. (JINS, 2011, 17, 796‐806)
Association studies for quantitative traits in structured populations

Association between disease and genetic polymorphisms often contributes critical information in our search for the genetic components of common diseases. Devlin and Roeder [1999: Biometrics 55:997-1004] introduced genomic control, a statistical method that overcomes a drawback to the use of population-based samples for tests of association, namely spurious associations induced by population structure. In essence, genomic control (GC) uses markers throughout the genome to adjust for any inflation in test statistics due to substructure. To date, genomic control (GC) has been developed for binary traits and bi- or multiallelic markers. Tests of association using GC have been limited to single genes. In this report, we generalize GC to quantitative traits (QT) and multilocus models. Using statistical analysis and simulations, we show that GC controls spurious associations in reasonable settings of population substructure for QT models, including gene-gene interaction. Through simulations, we explore GC power for both random and selected samples, assuming the QT locus tested is causal and its specific heritability is 2.5-5%. We find that GC, combined with either random or selected samples, has good power in this setting, and that more complex models induce smaller GC corrections. The latter suggests greater power can be achieved by specifying more complex genetic models, but this observation only follows when such models are largely correct and specified a priori.
The cyclic homology of affine algebras.

In this paper, we study the cyclic homology of affine algebras over a field of characteristic 0. We show that if A is such an algebra the inverse system (HC.+2m(A), S)m decomposes in sufficiently large degrees into the direct H*+2ttA sum of the constant system with value ~,'mz inf , ) and a system which is essentially zero. The essentially zero component is the kernel of the Loday- Quillen map l~ and the behavior of the restriction of S on it is closely related to the degeneracy of the spectral sequence associated with Connes' exact couple of A.
Job satisfaction, commitment, and involvement of information systems professionals

Eighty-three information systems professionals were randomly selected from a US state government agency, three information consulting firms and five FORTUNE 1000 firms. Multiple regression analyses were used to assess how age, career stage, most realistic position in five years, and such work environment factors as feedback, task independence, task identity, variety, uncertainty and autonomy contribute to job satisfaction, job commitment and job involvement. It was found that about 49 percent of variation of satisfaction, 55 percent of variation of commitment, and 21 percent of involvement could be explained in the multivariate regressional models. >
Effect of endotoxin on oleic acid lung injury does not depend on priming.

Recent studies have demonstrated significant synergistic physiological and biochemical effects between low-dose endotoxin (Etx) administration and oleic acid (OA)-induced canine lung injury. To evaluate whether this interaction depends on Etx priming of some key cell population, we compared the effects of giving low-dose Etx both after as well as before inducing lung injury with OA. In addition to hemodynamic and blood-gas measurements, positron emission tomographic imaging was used to measure edema accumulation and intrapulmonary blood flow distribution. Biochemical measurements of the stable metabolites of prostacyclin and thromboxane were obtained as well as measurements of isoprostanes and reactive sulfhydryls as evidence for possible concomitant oxidant production. We found that the physiological and biochemical effects of low-dose Etx developed 30–45 min after its administration, regardless of whether Etx was administered before or after OA. No increase in either isoprostane or reactive sulfhydryl production after Etx and/or OA was detected. These data suggest that the synergistic effect of low-dose Etx and OA-induced lung injury is not due to a priming effect of Etx.
Adult Human Mesenchymal Stem Cell Differentiation at the Cell Population and Single-Cell Levels Under Alternating Electric Current

Mesenchymal stem cells, precursors that can differentiate into osteoblasts, chondrocytes, and adipocytes, have tremendous potential for derivation of cells with specific (e.g., osteogenic) phenotypes for tissue engineering and tissue regeneration applications. To date, the predominant strategy to achieve directed differentiation of MSCs into osteoblasts was to recapitulate the normal developmental ontogeny of osteoblasts using growth factors (e.g., bone morphogenetic proteins). In contrast, the effects of biophysical stimuli alone on such outcomes remain, at best, partially understood. This in vitro study examined and optimized the effects of alternating electric current alone on the differentiation of adult human mesenchymal stem cells (hMSCs) at the cell population and single-cell levels. hMSCs, cultured on flat, indium-tin-oxide-coated glass in the absence of supplemented exogenous growth factors were exposed to alternating electric current (5–40 μA, 5–10 Hz frequency, sinusoidal waveform), for 1–24 h ...
An efficient pairwise key establishment scheme for Ad-Hoc Mobile Clouds

An Ad-hoc Mobile Cloud (AMC) is a new computing model that allows sharing computing power of multiple mobile devices. For a diverse group of individuals that employ such computing model, in an ad-hoc manner, secure peer-to-peer communication becomes very important. Using private or pairwise keys to secure such communication is preferable to public-keys because of computation and energy requirements [1]. With the advent of sensor enabled mobile devices, a protocol (SekGens) that uses sensor data to generate pairwise keys on demand has been proposed [2]. To work successfully SekGens requires devices to be closely located and becomes infeasible for devices situated multiple hops away. SekGens is also expensive in computation and slow in key generation. In this paper, we investigate how to enable devices in an AMC to establish pairwise keys. We propose an efficient solution which tries to reduce the number of executions of SekGens in the AMC, and establishes pairwise keys between nodes multiple hops away by distributing parts of the key on multiple routing paths. Our results show a reduction of up to 75% in the number of SekGens required to establish keys in an AMC, when compared to a naive approach.
Body mass index changes over 3 years and effect of obesity on community mobility for persons with chronic spinal cord injury

Objective: To identify the prevalence of obesity in persons with chronic spinal cord injury (SCI), determine change in body mass index (BMI) over time, and identify impact of obesity on community mobility.Design: Prospective three year longitudinal study.Setting: Outpatient clinic of rehabilitation center.Participants: Convenience sample of 222 persons with paraplegia between 2–20 years post SCI.Outcome Measures: BMI at baseline and three years; community mobility (daily wheelchair propulsion distance and velocity, average number of daily transfers and depression raises).Results: Participants were 34.1 (27.3, 40.3) years of age and median duration of SCI was 8.7 (3.2, 15.1) years. The SCI adjusted BMI classification identified 44% of participants as obese. BMI increased over time with 13% moving into a higher weight category. Median change in BMI was 0.46 (−0.92, 1.50) kg/m2 (z = −2.684, P = 0.007), and increased at a rate of 0.15 kg/m2/yr. Average BMI was negatively correlated with daily wheelchair propu...
New species and new collection records of aquatic beetles in the genus Ochthebius Leach from southern Africa (Coleoptera: Hydraenidae)

The southern African species of the water beetle genus Ochthebius Leach, 1815, are reviewed. Eight new species are described, and new collection records are given for eight previously described species, based on the examination and databasing of 8,919 specimens from 253 localities/events. Male genitalia of the new species are illustrated, and high resolution habitus images of the holotypes of new species are provided. Distribution maps are given for the 18 species of Ochthebius now known from southern Africa, including Namibia, South Africa, Lesotho, Zimbabwe, the extreme southern part of Angola, and the southern part of Mozambique. New species of Ochthebius are: O. anchorus (South Africa, KwaZulu-Natal Province, Oribi Gorge); O. bicomicus (South Africa, Western Cape Province, 22 mi. N. Nelspoort); O. bupunctus (Namibia, Kaokoveld, Kunene River, Swartbooisdrift); O. endroedyi (South Africa, North West Province, Barberspan); O. granulinus (South Africa, Western Cape Province, Elandsdrift); O. involatus (South Africa, Western Cape Province, near Kommetje); O. sitiensis (Namibia, Okau Fountain, 12.5 km inland); and O. zulu (South Africa, KwaZulu-Natal Province, Nqutu).
Can Results of Sales Promotion be Predicted

Can the part that promotion plays in making sales be quantitatively measured and predicted for the future?This author offers evidence that conditions in the marketplace are so unknown and change so...
Study on Cloud Computing Applications’ Security of Smart Grid

This paper introduces the features and information security risks of smart grid,and then discusses the cloud-based data disaster recovery and virus protection application of the two cloud model of smart grid,and finally describes cloud computing’ security risks and solutions of smart grid.