Titanium dioxide (TiO2) has been extensively investigated in solar energy applications, including heterogeneous photocatalysis and photovoltaics. For most TiO2 materials, charge recombination between ...photoexcited electrons and holes severely limits the efficiencies of solar energy conversion. Different strategies have been attempted to improve charge separation in TiO2 materials. This review focuses on three effective approaches to achieve enhanced charge separation by constructing mixed-phase TiO2, highly dispersed titanium oxides, and nanotubular TiO2 materials. Selected examples from the literature are discussed to demonstrate how the three approaches could be implemented in the context of photocatalytic water splitting, photocatalytic CO2 reduction, and dye-sensitized solar cells. The discussion provides useful insights regarding the design of new TiO2 nanostructures for use in solar energy conversion.
Obesity is an established risk factor for pancreatic ductal adenocarcinoma (PDA). Despite recent identification of metabolic alterations in this lethal malignancy, the metabolic dependencies of ...obesity-associated PDA remain unknown. Here we show that obesity-driven PDA exhibits accelerated growth and a striking transcriptional enrichment for pathways regulating nitrogen metabolism. We find that the mitochondrial form of arginase (ARG2), which hydrolyzes arginine into ornithine and urea, is induced upon obesity, and silencing or loss of ARG2 markedly suppresses PDA. In vivo infusion of
N-glutamine in obese mouse models of PDA demonstrates enhanced nitrogen flux into the urea cycle and infusion of
N-arginine shows that Arg2 loss causes significant ammonia accumulation that results from the shunting of arginine catabolism into alternative nitrogen repositories. Furthermore, analysis of PDA patient tumors indicates that ARG2 levels correlate with body mass index (BMI). The specific dependency of PDA on ARG2 rather than the principal hepatic enzyme ARG1 opens a therapeutic window for obesity-associated pancreatic cancer.Obesity is an established risk factor for pancreatic ductal adenocarcinoma (PDA). Here the authors show that obesity induces the expression of the mitochondrial form of arginase ARG2 in PDA and that ARG2 silencing or loss results in ammonia accumulation and suppression of obesity-driven PDA tumor growth.
Abstract Numbers of aggressive prostate cancer (aPC) cases are rising, but only a few risk factors have been identified. In this study, we introduce a systematic approach to integrate geospatial data ...into external exposome research using aPC cases from Pennsylvania. We demonstrate the association between several area-level exposome measures across five Social Determinants of Health domains (SDOH) and geographic areas identified as having elevated odds of aPC. Residential locations of Pennsylvania men diagnosed with aPC from 2005 to 2017 were linked to 37 county-/tract-level SDOH exosome measures. Variable reduction processes adopted from neighborhood-wide association study along with Bayesian geoadditive logistic regression were used to identify areas with elevated odds of aPC and exposome factors that significantly attenuated the odds and reduced the size of identified areas. Areas with significantly higher odds of aPC were explained by various SDOH exposome measures, though the extent of the reduction depended on geographic location. Some areas were associated with race (social context), health insurance (access), or tract-level poverty (economics), while others were associated with either county-level water quality or a combination of factors. Area-level exposome measures can guide future patient-level external exposome research and help design targeted interventions to reduce local cancer burden.
Although the comparison of fully differential ionization data for particle and antiparticle impact provides the ultimate tests of theoretical models, only very low antiparticle beam intensities are ...available. Hence, few experiments of this type have been performed. Therefore, available experimentally obtained single and double differential cross-sections, which are much easier to obtain, are compared in order to demonstrate differences when only the projectile mass or charge (+1 or −1) is changed. Included in the comparison are cross-sections calculated for positron and electron impact using a three-particle classical trajectory Monte Carlo method. The calculated cross-sections provide independent information about the ejected electron and the scattered projectile contributions, plus information about the impact parameters, all as functions of the collision kinematics. From these comparisons, suggestions as to where future investigations are both feasible and useful are provided.
The typical response of the adult mammalian pulmonary circulation to a low oxygen environment is vasoconstriction and structural remodelling of pulmonary arterioles, leading to chronic elevation of ...pulmonary artery pressure (pulmonary hypertension) and right ventricular hypertrophy. Some mammals, however, exhibit genetic resistance to hypoxia-induced pulmonary hypertension. We used a congenic breeding program and comparative genomics to exploit this variation in the rat and identified the gene Slc39a12 as a major regulator of hypoxia-induced pulmonary vascular remodelling. Slc39a12 encodes the zinc transporter ZIP12. Here we report that ZIP12 expression is increased in many cell types, including endothelial, smooth muscle and interstitial cells, in the remodelled pulmonary arterioles of rats, cows and humans susceptible to hypoxia-induced pulmonary hypertension. We show that ZIP12 expression in pulmonary vascular smooth muscle cells is hypoxia dependent and that targeted inhibition of ZIP12 inhibits the rise in intracellular labile zinc in hypoxia-exposed pulmonary vascular smooth muscle cells and their proliferation in culture. We demonstrate that genetic disruption of ZIP12 expression attenuates the development of pulmonary hypertension in rats housed in a hypoxic atmosphere. This new and unexpected insight into the fundamental role of a zinc transporter in mammalian pulmonary vascular homeostasis suggests a new drug target for the pharmacological management of pulmonary hypertension.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
We conduct a laboratory experiment to test a continuous-time model that represents a dynamic groundwater extraction problem in an infinite horizon. We compare the observations to the equilibrium path ...of the usual behaviours, for the case where the player is alone in extracting the resource (optimal control) and when two players extract the same resource simultaneously (differential game). We use a within-subjects design. This allows us to identify individual profiles of players playing alone and then characterize groups based on their composition with respect to these individual behaviours. We find that approximately a quarter of the players and groups succeed in playing (significantly) optimally, and none behave myopically. Moreover having an agent that behaved optimally in the control in the pair increases the likelihood that the group cooperates. We also identify other categories of players and groups that allows us to classify an additional 50% of the observations.
Mentoring is considered an evidence-based practice for violence prevention. This study presents a partial replication of the
Take Charge!
program implemented in partnership with Big Brothers Big ...Sisters of America (BBBS). One hundred and eighty-eight early adolescents (
M
age = 12.87; 61.17% male) who were treated for peer-related assault injury in two urban mid-Atlantic emergency departments were randomly assigned to receive a mentor from two BBBS affiliates. Mentors and organization staff were trained in the
Take Charge!
violence prevention curriculum, which had previously shown evidence of efficacy. Intent-to-treat analyses showed statistically significant improvements in conflict avoidance self-efficacy for the intervention group at 9 months and reductions in fighting at 21 months, but an increase in parental report of aggression at 9 months. Complier average causal effect models revealed evidence of an additional effect for reduced problem behavior at 21 months for intervention adolescents who received a mentor. No effects were found for youth-reported aggression, retaliatory attitudes, deviance acceptance, or commitment to learning. Sensitivity analyses suggested increased aggressive behavior for adolescents in the intervention group who did not receive a mentor (i.e., non-compliers). These findings extend the evidence-base for
Take Charge!
as a violence prevention curriculum for youth already engaged in violence to “real-world” implementation settings. However, they also suggest that challenges associated with providing youth with mentors can be consequential and that additional supports may be needed for these youth/parents. Clinical trials number: clinicaltrials.gov NCT01770873.
Background
Prucalopride is a 5‐HT4 receptor agonist with gastrointestinal prokinetic activities. This integrated analysis of data from three 12‐week, double‐blind trials evaluated the effect of ...prucalopride 2 mg q.d. on common constipation symptoms in women in whom laxatives had failed to provide adequate relief. The effect of prucalopride on bowel function was outside the scope of the analysis and has been described elsewhere.
Methods
Women with self‐reported inadequate relief from laxatives and included in the prucalopride 2 mg or placebo arm of the trials were selected for analysis. Symptom severity was determined with the Patient Assessment of Constipation Symptoms (PAC–SYM) questionnaire. Observed changes from baseline in individual item scores were also evaluated by calculating Cohen's D effect sizes using baseline standard deviation (SD) (>0.2–0.5, >0.5–0.8 and >0.8 for small, moderate and large effects, respectively).
Key Results
Data were analyzed for 936 women. The proportion of women with a PAC‐SYM severity score >2 at baseline was 50.0% for abdominal symptoms, 71.4% for stool symptoms, and 15.5% for rectal symptoms. Excluding the women without presence of a symptom at baseline from the effect size calculations showed that prucalopride 2 mg had a large effect (>0.8) on all PAC‐SYM items, including abdominal pain, abdominal discomfort, bloating, straining, and painful bowel movements. For abdominal symptoms and stool symptoms, effect sizes with prucalopride 2 mg were 1.3–2.3 times larger than those with placebo.
Conclusions & Inferences
Prucalopride 2 mg q.d. for 12 weeks alleviates common constipation symptoms in women in whom laxatives had failed to provide adequate relief.
This integrated analysis of three 12‐week clinical trials assessed the effect on symptoms of prucalopride 2 mg once daily, compared with placebo, in 936 women with self‐reported inadequate relief from laxatives. For women with symptoms at baseline, treatment with prucalopride 2 mg had a large effect (>0.8) on all items in the Patient Assessment of Constipation Symptoms (PAC‐SYM) questionnaire, including abdominal pain, abdominal discomfort, bloating, straining, and painful bowel movements. Prucalopride 2 mg once daily for 12 weeks alleviates common constipation symptoms in women in whom laxatives have failed to provide adequate relief.
We study the impact of discrete versus continuous time on the behavior of agents in the context of a dynamic common pool resource game. To this purpose, we consider a linear quadratic model and ...conduct a lab experiment in which agents exploit a renewable resource with an infinite horizon. We use a differential game for continuous time and derive its discrete time approximation. In the single agent setting, we fail to detect, on a battery of indicators, any difference between agents’ behavior in discrete and continuous time. Conversely, in the two-player setting, significantly more agents can be classified as myopic and end up with a low resource level in discrete time. Continuous time seems to allow for better cooperation and thus greater sustainability of the resource than does discrete time.
In this paper, we introduce a new way of looking at fuzzy intervals. Instead of considering them as fuzzy sets, we see them as crisp sets of entities we call gradual (real) numbers. They are a ...gradual extension of real numbers, not of intervals. Such a concept is apparently missing in fuzzy set theory. Gradual numbers basically have the same algebraic properties as real numbers, but they are functions. A fuzzy interval is then viewed as a pair of fuzzy thresholds, which are monotonic gradual real numbers. This view enables interval analysis to be directly extended to fuzzy intervals, without resorting to alpha-cuts, in agreement with Zadeh's extension principle. Several results show that interval analysis methods can be directly adapted to fuzzy interval computation where end- points of intervals are changed into left and right fuzzy bounds. Our approach is illustrated on two known problems: computing fuzzy weighted averages and determining fuzzy floats and latest starting times in activity network scheduling.
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