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Showing papers by "University of Nevada, Reno published in 2006"


Journal ArticleDOI
TL;DR: There are not enough well-controlled studies to conclude that ACT is generally more effective than other active treatments across the range of problems examined, but so far the data are promising.

4,777 citations


Journal ArticleDOI
TL;DR: Tolerance to a combination of different stress conditions, particularly those that mimic the field environment, should be the focus of future research programs aimed at developing transgenic crops and plants with enhanced tolerance to naturally occurring environmental conditions.

2,432 citations


Journal ArticleDOI
TL;DR: In this paper, the state-of-the-art of the physical principles and applications of forward osmosis as well as their strengths and limitations are presented, along with a review of the current state of the art.

2,235 citations


Journal ArticleDOI
TL;DR: Among healthy postmenopausal women, calcium with vitamin D supplementation resulted in a small but significant improvement in hip bone density, did not significantly reduce hip fracture, and increased the risk of kidney stones.
Abstract: Background The efficacy of calcium with vitamin D supplementation for preventing hip and other fractures in healthy postmenopausal women remains equivocal. Methods We recruited 36,282 postmenopausal women, 50 to 79 years of age, who were already enrolled in a Women's Health Initiative (WHI) clinical trial. We randomly assigned participants to receive 1000 mg of elemental calcium as calcium carbonate with 400 IU of vitamin D3 daily or placebo. Fractures were ascertained for an average follow-up period of 7.0 years. Bone density was measured at three WHI centers. Results Hip bone density was 1.06 percent higher in the calcium plus vitamin D group than in the placebo group (P<0.01). Intention-to-treat analysis indicated that participants receiving calcium plus vitamin D supplementation had a hazard ratio of 0.88 for hip fracture (95 percent confidence interval, 0.72 to 1.08), 0.90 for clinical spine fracture (0.74 to 1.10), and 0.96 for total fractures (0.91 to 1.02). The risk of renal calculi increased with...

1,765 citations


Journal ArticleDOI
08 Feb 2006-JAMA
TL;DR: A dietary intervention that reduced total fat intake and increased intakes of vegetables, fruits, and grains did not significantly reduce the risk of CHD, stroke, or CVD in postmenopausal women and achieved only modest effects on CVD risk factors, suggesting that more focused diet and lifestyle interventions may be needed to improve risk factors and reduce CVDrisk.
Abstract: ContextMultiple epidemiologic studies and some trials have linked diet with cardiovascular disease (CVD) prevention, but long-term intervention data are needed.ObjectiveTo test the hypothesis that a dietary intervention, intended to be low in fat and high in vegetables, fruits, and grains to reduce cancer, would reduce CVD risk.Design, Setting, and ParticipantsRandomized controlled trial of 48 835 postmenopausal women aged 50 to 79 years, of diverse backgrounds and ethnicities, who participated in the Women's Health Initiative Dietary Modification Trial. Women were randomly assigned to an intervention (19 541 [40%]) or comparison group (29 294 [60%]) in a free-living setting. Study enrollment occurred between 1993 and 1998 in 40 US clinical centers; mean follow-up in this analysis was 8.1 years.InterventionIntensive behavior modification in group and individual sessions designed to reduce total fat intake to 20% of calories and increase intakes of vegetables/fruits to 5 servings/d and grains to at least 6 servings/d. The comparison group received diet-related education materials.Main Outcome MeasuresFatal and nonfatal coronary heart disease (CHD), fatal and nonfatal stroke, and CVD (composite of CHD and stroke).ResultsBy year 6, mean fat intake decreased by 8.2% of energy intake in the intervention vs the comparison group, with small decreases in saturated (2.9%), monounsaturated (3.3%), and polyunsaturated (1.5%) fat; increases occurred in intakes of vegetables/fruits (1.1 servings/d) and grains (0.5 serving/d). Low-density lipoprotein cholesterol levels, diastolic blood pressure, and factor VIIc levels were significantly reduced by 3.55 mg/dL, 0.31 mm Hg, and 4.29%, respectively; levels of high-density lipoprotein cholesterol, triglycerides, glucose, and insulin did not significantly differ in the intervention vs comparison groups. The numbers who developed CHD, stroke, and CVD (annualized incidence rates) were 1000 (0.63%), 434 (0.28%), and 1357 (0.86%) in the intervention and 1549 (0.65%), 642 (0.27%), and 2088 (0.88%) in the comparison group. The diet had no significant effects on incidence of CHD (hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.90-1.06), stroke (HR, 1.02; 95% CI, 0.90-1.15), or CVD (HR, 0.98; 95% CI, 0.92-1.05). Excluding participants with baseline CVD (3.4%), the HRs (95% CIs) for CHD and stroke were 0.94 (0.86-1.02) and 1.02 (0.90-1.17), respectively. Trends toward greater reductions in CHD risk were observed in those with lower intakes of saturated fat or trans fat or higher intakes of vegetables/fruits.ConclusionsOver a mean of 8.1 years, a dietary intervention that reduced total fat intake and increased intakes of vegetables, fruits, and grains did not significantly reduce the risk of CHD, stroke, or CVD in postmenopausal women and achieved only modest effects on CVD risk factors, suggesting that more focused diet and lifestyle interventions may be needed to improve risk factors and reduce CVD risk.Clinical Trials RegistrationClinicalTrials.gov Identifier: NCT00000611

1,000 citations


Journal ArticleDOI
TL;DR: In this article, the authors systematically analyze the possible physical processes that shape the properties of the early X-ray afterglow light curves and use the data to constrain various models.
Abstract: With the successful launch of the Swift Gamma-Ray Burst Explorer, a rich trove of early X-ray afterglow data has been collected by its onboard X-Ray Telescope (XRT). Some interesting features are emerging, including a distinct rapidly decaying component preceding the conventional afterglow component in many sources, a shallow decay component before the more "normal'' decay component observed in a good fraction of GRBs, and X-ray flares in nearly half of the afterglows. In this paper we systematically analyze the possible physical processes that shape the properties of the early X-ray afterglow light curves and use the data to constrain various models. We suggest that the steep decay component is consistent with the tail emission of the prompt gamma-ray bursts and/or the X-ray flares. This provides strong evidence that the prompt emission and afterglow emission are likely two distinct components, supporting the internal origin of the GRB prompt emission. The shallow decay segment observed in a group of GRBs suggests that very likely the forward shock keeps being refreshed for some time. This might be caused by either a long-lived central engine, or a wide distribution of the shell Lorentz factors, or else possibly the deceleration of a Poynting flux-dominated flow. X-ray flares suggest that the GRB central engine is very likely still active after the prompt gamma-ray emission is over, but with a reduced activity at later times. In some cases, the central engine activity even extends to days after the burst triggers. Analyses of early X-ray afterglow data reveal that GRBs are indeed highly relativistic events and that early afterglow data of many bursts, starting from the beginning of the XRT observations, are consistent with the afterglow emission from an ISM environment.

998 citations


Journal ArticleDOI
TL;DR: Daily supplementation of calcium with vitamin D for seven years had no effect on the incidence of colorectal cancer among postmenopausal women, and the long latency associated with the development of colorescopy cancer, along with the seven-year duration of the trial, may have contributed to this null finding.
Abstract: Background Higher intake of calcium and vitamin D has been associated with a reduced risk of colorectal cancer in epidemiologic studies and polyp recurrence in polyp-prevention trials. However, randomized-trial evidence that calcium with vitamin D supplementation is beneficial in the primary prevention of colorectal cancer is lacking. Methods We conducted a randomized, double-blind, placebo-controlled trial involving 36,282 postmenopausal women from 40 Women’s Health Initiative centers: 18,176 women received 500 mg of elemental calcium as calcium carbonate with 200 IU of vitamin D3 twice daily (1000 mg of elemental calcium and 400 IU of vitamin D3) and 18,106 received a matching placebo for an average of 7.0 years. The incidence of pathologically confirmed colorectal cancer was the designated secondary outcome. Baseline levels of serum 25-hydroxyvitamin D were assessed in a nested case–control study. Results The incidence of invasive colorectal cancer did not differ significantly between women assigned to calcium plus vitamin D supplementation and those assigned to placebo (168 and 154 cases; hazard ratio, 1.08; 95 percent confidence interval, 0.86 to 1.34; P = 0.51), and the tumor characteristics were similar in the two groups. The frequency of colorectal-cancer screening and abdominal symptoms was similar in the two groups. There were no significant treatment interactions with baseline characteristics. Conclusions Daily supplementation of calcium with vitamin D for seven years had no effect on the incidence of colorectal cancer among postmenopausal women. The long latency associated with the development of colorectal cancer, along with the seven-year duration of the trial, may have contributed to this null finding. Ongoing follow-up will assess the longer-term effect of this intervention. (ClinicalTrials.gov number, NCT00000611.)

970 citations


Journal ArticleDOI
TL;DR: A model for the involvement of ROS in temperature stress sensing and defense is proposed and it is likely that in plants this network is interlinked with the different networks that control temperature stress acclimation and tolerance.
Abstract: Temperature stress can have a devastating effect on plant metabolism, disrupting cellular homeostasis, and uncoupling major physiological processes. A direct result of stress-induced cellular changes is the enhanced accumulation of toxic compounds in cells that include reactive oxygen species (ROS). Although a considerable amount of work has shown a direct link between ROS scavenging and plant tolerance to temperature stress, recent studies have shown that ROS could also play a key role in mediating important signal transduction events. Thus, ROS, such as superoxide (O2–), are produced by NADPH oxidases during abiotic stress to activate stress-response pathways and induce defense mechanisms. The rates and cellular sites of ROS production during temperature stress could play a central role in stress perception and protection. ROS levels, as well as ROS signals, are thought to be controlled by the ROS gene network of plants. It is likely that in plants this network is interlinked with the different networks that control temperature stress acclimation and tolerance. In this review paper, we attempt to summarize some of the recent studies linking ROS and temperature stress in plants and propose a model for the involvement of ROS in temperature stress sensing and defense.

958 citations


Journal ArticleDOI
TL;DR: Doctors, mental health, and social service providers should address depression, substance abuse, and forced sex in an attempt to reduce suicidal behaviors among transgender persons.
Abstract: To determine the independent predictors of attempted suicide among transgender persons we interviewed 392 male-to-female (MTF) and 123 female-to-male (FTM) individuals. Participants were recruited through targeted sampling, respondent-driven sampling, and agency referrals in San Francisco. The prevalence of attempted suicide was 32% (95% CI = 28% to 36%). In multivariate logistic regression analysis younger age (<25 years), depression, a history of substance abuse treatment, a history of forced sex, gender-based discrimination, and gender-based victimization were independently associated with attempted suicide. Suicide prevention interventions for transgender persons are urgently needed, particularly for young people. Medical, mental health, and social service providers should address depression, substance abuse, and forced sex in an attempt to reduce suicidal behaviors among transgender persons. In addition, increasing societal acceptance of the transgender community and decreasing gender-based ...

874 citations


Journal ArticleDOI
TL;DR: In this paper, the authors examined some practical numerical methods to solve a class of initial-boundary value fractional partial differential equations with variable coefficients on a finite domain, and the stability, consistency, and (therefore) convergence of the methods are discussed.

836 citations


Journal ArticleDOI
TL;DR: In this paper, the authors proposed that IT-enabled supply chain capabilities are firm-specific, and hard-to-copy across organizations, and provided a new perspective in evaluating IT investment in the supply chain process.

Journal ArticleDOI
TL;DR: Gunstone et al. as discussed by the authors reviewed recent research on self-regulated learning and discuss the implications of this research for science education, focusing on three components of selfregulated learning including cognition, metacognition, and motivation.
Abstract: The purpose of this article is to review recent research on self-regulated learning and discuss the implications of this research for science education. We draw on examples of self-regulated learning from the science education literature to summarise and illustrate effective instructional methods and the development of metacognitive understanding (Gunstone; 1999a; Rickey & Stacy, 2000; White & Mitchell, 1994). We also focus on the crucial role that metacognition plays in self-regulation (Baird & White, 1996; Nichols, Tippins, & Wieseman, 1997; White, 1998). We divide our discussion into two main parts. The first focuses on three components of selfregulated learning, including cognition, metacognition, and motivation. We relate these aspects of self-regulation to current practices in science education. The second section focuses on six general instructional strategies for improving self-regulation in the science classroom. We focus on the use of inquiry based learning, the role of collaborative support, strategy and problem solving instruction, the construction of mental models, the use of technology to support learning, and the role of personal beliefs such as self-efficacy and epistemological world views. These instructional strategies are selected because they reflect extensive research agendas over the last decade within the science education literature and are essential to metacognition and self-regulation (Butler & Winne, 1995; Gunstone, 1999b).

Journal ArticleDOI
08 Feb 2006-JAMA
TL;DR: Among postmenopausal women, a low-fat dietary pattern did not result in a statistically significant reduction in invasive breast cancer risk over an 8.1-year average follow-up period, and the nonsignificant trends observed indicate that longer, planned, nonintervention follow- up may yield a more definitive comparison.
Abstract: ContextThe hypothesis that a low-fat dietary pattern can reduce breast cancer risk has existed for decades but has never been tested in a controlled intervention trial.ObjectiveTo assess the effects of undertaking a low-fat dietary pattern on breast cancer incidence.Design and SettingA randomized, controlled, primary prevention trial conducted at 40 US clinical centers from 1993 to 2005.ParticipantsA total of 48 835 postmenopausal women, aged 50 to 79 years, without prior breast cancer, including 18.6% of minority race/ethnicity, were enrolled.InterventionsWomen were randomly assigned to the dietary modification intervention group (40% [n = 19 541]) or the comparison group (60% [n = 29 294]). The intervention was designed to promote dietary change with the goals of reducing intake of total fat to 20% of energy and increasing consumption of vegetables and fruit to at least 5 servings daily and grains to at least 6 servings daily. Comparison group participants were not asked to make dietary changes.Main Outcome MeasureInvasive breast cancer incidence.ResultsDietary fat intake was significantly lower in the dietary modification intervention group compared with the comparison group. The difference between groups in change from baseline for percentage of energy from fat varied from 10.7% at year 1 to 8.1% at year 6. Vegetable and fruit consumption was higher in the intervention group by at least 1 serving per day and a smaller, more transient difference was found for grain consumption. The number of women who developed invasive breast cancer (annualized incidence rate) over the 8.1-year average follow-up period was 655 (0.42%) in the intervention group and 1072 (0.45%) in the comparison group (hazard ratio, 0.91; 95% confidence interval, 0.83-1.01 for the comparison between the 2 groups). Secondary analyses suggest a lower hazard ratio among adherent women, provide greater evidence of risk reduction among women having a high-fat diet at baseline, and suggest a dietary effect that varies by hormone receptor characteristics of the tumor.ConclusionsAmong postmenopausal women, a low-fat dietary pattern did not result in a statistically significant reduction in invasive breast cancer risk over an 8.1-year average follow-up period. However, the nonsignificant trends observed suggesting reduced risk associated with a low-fat dietary pattern indicate that longer, planned, nonintervention follow-up may yield a more definitive comparison.Clinical Trials RegistrationClinicalTrials.gov Identifier: NCT00000611

Journal ArticleDOI
26 Jan 2006-Nature
TL;DR: Quasi-monoenergetic laser-driven C5+ ions with a vastly reduced energy spread are reported, which may enable significant advances in the development of compact MeV ion accelerators, new diagnostics, medical physics, inertial confinement fusion and fast ignition.
Abstract: Acceleration of particles by intense laser-plasma interactions represents a rapidly evolving field of interest, as highlighted by the recent demonstration of laser-driven relativistic beams of monoenergetic electrons. Ultrahigh-intensity lasers can produce accelerating fields of 10 TV m(-1) (1 TV = 10(12) V), surpassing those in conventional accelerators by six orders of magnitude. Laser-driven ions with energies of several MeV per nucleon have also been produced. Such ion beams exhibit unprecedented characteristics--short pulse lengths, high currents and low transverse emittance--but their exponential energy spectra have almost 100% energy spread. This large energy spread, which is a consequence of the experimental conditions used to date, remains the biggest impediment to the wider use of this technology. Here we report the production of quasi-monoenergetic laser-driven C5+ ions with a vastly reduced energy spread of 17%. The ions have a mean energy of 3 MeV per nucleon (full-width at half-maximum approximately 0.5 MeV per nucleon) and a longitudinal emittance of less than 2 x 10(-6) eV s for pulse durations shorter than 1 ps. Such laser-driven, high-current, quasi-monoenergetic ion sources may enable significant advances in the development of compact MeV ion accelerators, new diagnostics, medical physics, inertial confinement fusion and fast ignition.

Journal ArticleDOI
08 Feb 2006-JAMA
TL;DR: A low-fat dietary pattern intervention did not reduce the risk of colorectal cancer in postmenopausal women during 8.1 years of follow-up, and secondary analyses suggested potential interactions with baseline aspirin use and combined estrogen-progestin use status.
Abstract: ContextObservational studies and polyp recurrence trials are not conclusive regarding the effects of a low-fat dietary pattern on risk of colorectal cancer, necessitating a primary prevention trial.ObjectiveTo evaluate the effects of a low-fat eating pattern on risk of colorectal cancer in postmenopausal women.Design, Setting, and ParticipantsThe Women’s Health Initiative Dietary Modification Trial, a randomized controlled trial conducted in 48 835 postmenopausal women aged 50 to 79 years recruited between 1993 and 1998 from 40 clinical centers throughout the United States.InterventionsParticipants were randomly assigned to the dietary modification intervention (n = 19 541; 40%) or the comparison group (n = 29 294; 60%).The intensive behavioral modification program aimed to motivate and support reductions in dietary fat, to increase consumption of vegetables and fruits, and to increase grain servings by using group sessions, self-monitoring techniques, and other tailored and targeted strategies. Women in the comparison group continued their usual eating pattern.Main Outcome MeasureInvasive colorectal cancer incidence.ResultsA total of 480 incident cases of invasive colorectal cancer occurred during a mean follow-up of 8.1 (SD, 1.7) years. Intervention group participants significantly reduced their percentage of energy from fat by 10.7% more than did the comparison group at 1 year, and this difference between groups was mostly maintained (8.1% at year 6). Statistically significant increases in vegetable, fruit, and grain servings were also made. Despite these dietary changes, there was no evidence that the intervention reduced the risk of invasive colorectal cancer during the follow-up period. There were 201 women with invasive colorectal cancer (0.13% per year) in the intervention group and 279 (0.12% per year) in the comparison group (hazard ratio, 1.08; 95% confidence interval, 0.90-1.29). Secondary analyses suggested potential interactions with baseline aspirin use and combined estrogen-progestin use status (P = .01 for each). Colorectal examination rates, although not protocol defined, were comparable between the intervention and comparison groups. Similar results were seen in analyses adjusting for adherence to the intervention.ConclusionIn this study, a low-fat dietary pattern intervention did not reduce the risk of colorectal cancer in postmenopausal women during 8.1 years of follow-up.Clinical Trials RegistrationClinicalTrials.gov Identifier: NCT00000611

Journal ArticleDOI
TL;DR: In this paper, the authors show that the surface enrichment is the result of a minor amount of transport and deposition by aqueous processes on the surface of olivine-bearing basalts.
Abstract: Spirit landed on the floor of Gusev Crater and conducted initial operations on soil covered, rock-strewn cratered plains underlain by olivine-bearing basalts. Plains surface rocks are covered by wind-blown dust and show evidence for surface enrichment of soluble species as vein and void-filling materials and coatings. The surface enrichment is the result of a minor amount of transport and deposition by aqueous processes. Layered granular deposits were discovered in the Columbia Hills, with outcrops that tend to dip conformably with the topography. The granular rocks are interpreted to be volcanic ash and/or impact ejecta deposits that have been modified by aqueous fluids during and/or after emplacement. Soils consist of basaltic deposits that are weakly cohesive, relatively poorly sorted, and covered by a veneer of wind blown dust. The soils have been homogenized by wind transport over at least the several kilometer length scale traversed by the rover. Mobilization of soluble species has occurred within at least two soil deposits examined. The presence of mono-layers of coarse sand on wind-blown bedforms, together with even spacing of granule-sized surface clasts, suggest that some of the soil surfaces encountered by Spirit have not been modified by wind for some time. On the other hand, dust deposits on the surface and rover deck have changed during the course of the mission. Detection of dust devils, monitoring of the dust opacity and lower boundary layer, and coordinated experiments with orbiters provided new insights into atmosphere-surface dynamics.

Journal ArticleDOI
TL;DR: Slow wave frequency is regulated by a variety of physiological agonists and conditions, and shifts in pacemaker dominance can occur in response to both neural and nonneural inputs.
Abstract: ▪ Abstract In the gastrointestinal tract, phasic contractions are caused by electrical activity termed slow waves. Slow waves are generated and actively propagated by interstitial cells of Cajal (ICC). The initiation of pacemaker activity in the ICC is caused by release of Ca2+ from inositol 1,4,5-trisphosphate (IP3) receptor–operated stores, uptake of Ca2+ into mitochondria, and the development of unitary currents. Summation of unitary currents causes depolarization and activation of a dihydropyridine-resistant Ca2+ conductance that entrains pacemaker activity in a network of ICC, resulting in the active propagation of slow waves. Slow wave frequency is regulated by a variety of physiological agonists and conditions, and shifts in pacemaker dominance can occur in response to both neural and nonneural inputs. Loss of ICC in many human motility disorders suggests exciting new hypotheses for the etiology of these disorders.

Journal ArticleDOI
TL;DR: Findings show important functions of the CPK6 and CPK3 CDPKs in guard cell ion channel regulation and provide genetic evidence for calcium sensors that transduce stomatal ABA signaling.
Abstract: Abscisic acid (ABA) signal transduction has been proposed to utilize cytosolic Ca2+ in guard cell ion channel regulation. However, genetic mutants in Ca2+ sensors that impair guard cell or plant ion channel signaling responses have not been identified, and whether Ca2+-independent ABA signaling mechanisms suffice for a full response remains unclear. Calcium-dependent protein kinases (CDPKs) have been proposed to contribute to central signal transduction responses in plants. However, no Arabidopsis CDPK gene disruption mutant phenotype has been reported to date, likely due to overlapping redundancies in CDPKs. Two Arabidopsis guard cell–expressed CDPK genes, CPK3 and CPK6, showed gene disruption phenotypes. ABA and Ca2+ activation of slow-type anion channels and, interestingly, ABA activation of plasma membrane Ca2+-permeable channels were impaired in independent alleles of single and double cpk3cpk6 mutant guard cells. Furthermore, ABA- and Ca2+-induced stomatal closing were partially impaired in these cpk3cpk6 mutant alleles. However, rapid-type anion channel current activity was not affected, consistent with the partial stomatal closing response in double mutants via a proposed branched signaling network. Imposed Ca2+ oscillation experiments revealed that Ca2+-reactive stomatal closure was reduced in CDPK double mutant plants. However, long-lasting Ca2+-programmed stomatal closure was not impaired, providing genetic evidence for a functional separation of these two modes of Ca2+-induced stomatal closing. Our findings show important functions of the CPK6 and CPK3 CDPKs in guard cell ion channel regulation and provide genetic evidence for calcium sensors that transduce stomatal ABA signaling.

Journal ArticleDOI
TL;DR: It is shown that the fractional Crank-Nicholson method based on the shifted Grunwald formula is unconditionally stable and compared with the exact analytical solution for its order of convergence.

Journal ArticleDOI
16 Nov 2006-Nature
TL;DR: It is shown that about two-thirds of the endpoints of strike-slip earthquake ruptures are associated with fault steps or the termini of active fault traces, and that there exists a limiting dimension of fault step above which earthquake rupture do not propagate and below which rupture propagation ceases only about 40 per cent of the time.
Abstract: The active fault traces on which earthquakes occur are generally not continuous, and are commonly composed of segments that are separated by discontinuities that appear as steps in map-view. Stress concentrations resulting from slip at such discontinuities may slow or stop rupture propagation and hence play a controlling role in limiting the length of earthquake rupture. Here I examine the mapped surface rupture traces of 22 historical strike-slip earthquakes with rupture lengths ranging between 10 and 420 km. I show that about two-thirds of the endpoints of strike-slip earthquake ruptures are associated with fault steps or the termini of active fault traces, and that there exists a limiting dimension of fault step (3-4 km) above which earthquake ruptures do not propagate and below which rupture propagation ceases only about 40 per cent of the time. The results are of practical importance to seismic hazard analysis where effort is spent attempting to place limits on the probable length of future earthquakes on mapped active faults. Physical insight to the dynamics of the earthquake rupture process is further gained with the observation that the limiting dimension appears to be largely independent of the earthquake rupture length. It follows that the magnitude of stress changes and the volume affected by those stress changes at the driving edge of laterally propagating ruptures are largely similar and invariable during the rupture process regardless of the distance an event has propagated or will propagate.

Journal ArticleDOI
TL;DR: Multineuron patch-clamp recordings in the ferret medial prefrontal cortex showed a heterogeneity of synapses interconnecting distinct subnetworks of different pyramidal cells, which could amplify recurrent interactions between pyramides and support persistent activity in the prefrontal cortex.
Abstract: The prefrontal cortex is specially adapted to generate persistent activity that outlasts stimuli and is resistant to distractors, presumed to be the basis of working memory. The pyramidal network that supports this activity is unknown. Multineuron patch-clamp recordings in the ferret medial prefrontal cortex showed a heterogeneity of synapses interconnecting distinct subnetworks of different pyramidal cells. One subnetwork was similar to the pyramidal network commonly found in primary sensory areas, consisting of accommodating pyramidal cells interconnected with depressing synapses. The other subnetwork contained complex pyramidal cells with dual apical dendrites displaying nonaccommodating discharge patterns; these cells were hyper-reciprocally connected with facilitating synapses displaying pronounced synaptic augmentation and post-tetanic potentiation. These cellular, synaptic and network properties could amplify recurrent interactions between pyramidal neurons and support persistent activity in the prefrontal cortex.

Posted Content
TL;DR: In this article, the authors show that individuals with lower risk aversion are more likely to become self-employed, whereas for individuals coming out of unemployment or inactivity risk attitudes do not seem to play a role in the decision process.
Abstract: The influence of risk aversion on the decision to become self-employed is a much discussed topic in the entrepreneurial literature. Conventional wisdom asserts that the role model of an entrepreneur requires to make risky decisions in uncertain environments and hence that more risk-averse individuals are less likely to become an entrepreneur. Empirical tests of this assumption are scarce however, mainly because reliable measures for risk-aversion are not available. We base our analysis on the most recent waves of the German Socio-Economic Panel (SOEP) which allow us to use experimentally-validated measures of risk attitudes. Most importantly and in contrast to previous research, we are able to examine whether the decision of starting a business is influenced by objectively measurable risk attitudes at the time when this decision is made. Our results show that in general individuals with lower risk aversion are more likely to become self-employed. Sensitivity analysis reveals, however, that this is true only for people coming out of regular employment, whereas for individuals coming out of unemployment or inactivity risk attitudes do not seem to play a role in the decision process.

Journal ArticleDOI
TL;DR: Evidence is presented obtained from microarray expression studies in Arabidopsis that the Hsf gene network is highly flexible and specialized, with specific members and/or member combinations controlling the response of plants to particular stress conditions.

Journal ArticleDOI
TL;DR: The acceleration of high-energy ion beams (up to several tens of mega-electron-volts per nucleon) following the interaction of short (t 1018 W˙cm-2˙μm-2) laser pulses w...
Abstract: The acceleration of high-energy ion beams (up to several tens of mega-electron-volts per nucleon) following the interaction of short (t 1018 W˙cm-2˙μm-2) laser pulses w...

Journal ArticleDOI
TL;DR: The results suggest that Zat10 plays a key role as both a positive and a negative regulator of plant defenses, as well as boosting the tolerance of plants to salinity, heat and osmotic stress.

Journal ArticleDOI
TL;DR: In this article, a practical alternating directions implicit method to solve a class of two-dimensional initial-boundary value fractional partial differential equations with variable coefficients on a finite domain is discussed.

Journal ArticleDOI
TL;DR: It is demonstrated that large firms, as well as those that have been relying on outsourcing or EDI, tended to be slow to migrate to the internet platform, while firm size, partner usage, electronic data interchange (EDI) usage, and perceived obstacles were found to negatively affect e-commerce migration.

Journal ArticleDOI
TL;DR: The present study demonstrates that terahertz spectroscopy is a sensitive tool to detect solute-induced changes in the water network and is shown to probe the collective modes in theWater network.
Abstract: The dynamics of water surrounding a solute is of fundamental importance in chemistry and biology. The properties of water molecules near the surface of a bio-molecule have been the subject of numerous, sometimes controversial experimental and theoretical studies, with some suggesting the existence of rather rigid water structures around carbohydrates and proteins [Pal, S. K., Peon, J., Bagchi, B. & Zewail A. H. (2002) J. Phys. Chem. B 106, 12376–12395]. Hydrogen bond rearrangement in water occurs on the picosecond time scale, so relevant experiments must access these times. Here, we show that terahertz spectroscopy can directly investigate hydration layers. By a precise measurement of absorption coefficients between 2.3 THz and 2.9 THz we could determine the size and the characteristics of the hydration shell. The hydration layer around a carbohydrate (lactose) is determined to extend to 5.13 ± 0.24 A from the surface corresponding to ≈123 water molecules beyond the first solvation shell. Accompanying molecular modeling calculations support this result and provide a microscopic visualization. Terahertz spectroscopy is shown to probe the collective modes in the water network. The observed increase of the terahertz absorption of the water in the hydration layer is explained in terms of coherent oscillations of the hydration water and solute. Simulations also reveal a slowing down of the hydrogen bond rearrangement dynamics for water molecules near lactose, which occur on the picosecond time scale. The present study demonstrates that terahertz spectroscopy is a sensitive tool to detect solute-induced changes in the water network.

Journal ArticleDOI
TL;DR: This article used a within-subject, repeated measures design to test the effects of a 2-day group Acceptance and Commitment Therapy workshop on 20 normal parents/guardians of children diagnosed with autism.
Abstract: Parents of autistic children face enormous challenges, but very little attention has been paid to their psychological needs. Acceptance and Commitment Therapy (ACT) has previously been tested with parents as part of a comprehensive package, but not yet alone. The present study used a within-subject, repeated measures design to test the effects of a 2-day (14 hour) group ACT workshop on 20 normal parents/guardians of children diagnosed with autism. Parents were assessed three weeks before the workshop, one week before, one week after, and three months after. No significant change occurred while waiting for treatment, but pre to post improvements were found on the Beck Depression Inventory-II (BDI-II), and the Global Severity Index (GSI) of the Brief Symptom Inventory (BSI). Significant pre to follow-up improvements were observed on the BDI-II, BSI, and the General Health Questionnaire-12. Processes measures of experiential avoidance and cognitive fusion also changed and there was some evidence tha...

Journal ArticleDOI
TL;DR: This paper used a door-to-door fundraising field experiment to explore the economics of charity and found that a one standard deviation increase in female solicitor physical attractiveness is similar to that of the lottery incentive.
Abstract: This study develops theory and uses a door-to-door fundraising field experiment to explore the economics of charity. We approached nearly 5000 households, randomly divided into four experimental treatments, to shed light on key issues on the demand side of charitable fundraising. Empirical results are in line with our theory: in gross terms, our lottery treatments raised considerably more money than our voluntary contributions treatments. Interestingly, we find that a one standard deviation increase in female solicitor physical attractiveness is similar to that of the lottery incentive—the magnitude of the estimated difference in gifts is roughly equivalent to the treatment effect of moving from our theoretically most attractive approach (lotteries) to our least attractive approach (voluntary contributions).