Time evolution in linear response: Boltzmann equations and beyond

In this work a perturbative linear response analysis is performed for the time evolution of the quasi-conserved charge of a scalar field. One can find two regimes, one follows exponential damping, where the damping rate is shown to come from quantum Boltzmann equations. The other regime (coming from multiparticle cuts and products of them) decays as power law. The most important, non-oscillating contribution in our model comes from a 4-particle intermediate state and decays as 1/t^3. These results may have relevance for instance in the context of lepton number violation in the Early Universe.Comment: 19 page

Geometric phase effects for wavepacket revivals

The study of wavepacket revivals is extended to the case of Hamiltonians which are made time-dependent through the adiabatic cycling of some parameters. It is shown that the quantal geometric phase (Berry's phase) causes the revived packet to be displaced along the classical trajectory, by an amount equal to the classical geometric phase (Hannay's angle), in one degree of freedom. A physical example illustrating this effect in three degrees of freedom is mentioned.Comment: Revtex, 11 pages, no figures

New empirical fits to the proton electromagnetic form factors

Recent measurements of the ratio of the elastic electromagnetic form factors of the proton, G_Ep/G_Mp, using the polarization transfer technique at Jefferson Lab show that this ratio decreases dramatically with increasing Q^2, in contradiction to previous measurements using the Rosenbluth separation technique. Using this new high quality data as a constraint, we have reanalyzed most of the world e-p elastic cross section data. In this paper, we present a new empirical fit to the reanalyzed data for the proton elastic magnetic form factor in the region 0 < Q^2 < 30 GeV^2. As well, we present an empirical fit to the proton electromagnetic form factor ratio, G_Ep/G_Mp, which is valid in the region 0.1 < Q^2 < 6 GeV^2

Arsenic Cancer Risk Confounder in Southwest Taiwan Data Set

Quantitative analysis for the risk of human cancer from the ingestion of inorganic arsenic has been based on the reported cancer mortality experience in the blackfoot disease (BFD)–endemic area of southwest Taiwan. Linear regression analysis shows that arsenic as the sole etiologic factor accounts for only 21% of the variance in the village standardized mortality ratios for bladder and lung cancer. A previous study had reported the influence of confounders (township, BFD prevalence, and artesian well dependency) qualitatively, but they have not been introduced into a quantitative assessment. In this six-township study, only three townships (2, 4, and 6) showed a significant positive dose–response relationship with arsenic exposure. The other three townships (0, 3, and 5) demonstrated significant bladder and lung cancer risks that were independent of arsenic exposure. The data for bladder and lung cancer mortality for townships 2, 4, and 6 fit an inverse linear regression model (p < 0.001) with an estimated threshold at 151 μg/L (95% confidence interval, 42 to 229 μg/L). Such a model is consistent with epidemiologic and toxicologic literature for bladder cancer. Exploration of the southwest Taiwan cancer mortality data set has clarified the dose–response relationship with arsenic exposure by separating out township as a confounding factor

Study protocol: evaluation of a parenting and stress management programme: a randomised controlled trial of Triple P discussion groups and stress control

&lt;br&gt;Background: Children displaying psychosocial problems are at an increased risk of negative developmental outcomes. Parenting practices are closely linked with child development and behaviour, and parenting programmes have been recommended in the treatment of child psychosocial problems. However, parental mental health also needs to be addressed when delivering parenting programmes as it is linked with parenting practices, child outcomes, and treatment outcomes of parenting programmes. This paper describes the protocol of a study examining the effects of a combined intervention of a parenting programme and a cognitive behavioural intervention for mental health problems.&lt;/br&gt; &lt;br&gt;Methods: The effects of a combined intervention of Triple P Discussion Groups and Stress Control will be examined using a randomised controlled trial design. Parents with a child aged 3?8?years will be recruited to take part in the study. After obtaining informed consent and pre-intervention measures, participants will be randomly assigned to either an intervention or a waitlist condition. The two primary outcomes for this study are change in dysfunctional/ineffective parenting practices and change in symptoms of depression, anxiety, and stress. Secondary outcomes are child behaviour problems, parenting experiences, parental self-efficacy, family relationships, and positive parental mental health. Demographic information, participant satisfaction with the intervention, and treatment fidelity data will also be collected. Data will be collected at pre-intervention, mid-intervention, post-intervention, and 3-month follow-up.&lt;/br&gt; &lt;br&gt;Discussion: The aim of this paper is to describe the study protocol of a randomised controlled trial evaluating the effects of a combined intervention of Triple P Discussion Groups and Stress Control in comparison to a waitlist condition. This study is important because it will provide evidence about the effects of this combined intervention for parents with 3?8?year old children. The results of the study could be used to inform policy about parenting support and support for parents with mental health problems. Trial registration ClinicalTrial.gov: NCT01777724, UTN: U1111-1137-1053.&lt;/br&gt

Structure of HIV-1 reverse transcriptase in a complex with the non-nucleoside inhibitor α-APA R 95845 at 2.8 å resolution

AbstractBackground: HIV-1 reverse transcriptase (RT) is a multifunctional enzyme that copies the RNA genome of HIV-1 into DNA. It is a heterodimer composed of a 66 kDa (p66) and a 51 kDa (p51) subunit. HIV-1 RT is a crucial target for structure-based drug design, and potent inhibitors have been identified, whose efficacy, however, is limited by drug resistance.Results The crystal structure of HIV-1 RT in complex with the non-nucleoside inhibitor α-anilinophenylacetamide (α-APA) R 95845 has been determined at 2.8 å resolution. The inhibitor binds in a hydrophobic pocket near the polymerase active site. The pocket contains five aromatic amino acid residues and the interactions of the side chains of these residues with the aromatic rings of non-nucleoside inhibitors appear to be important for inhibitor binding. Most of the amino acid residues where mutations have been correlated with high levels of resistance to non-nucleoside inhibitors of HIV-1 RT are located close to α-APA. The overall fold of HIV-1 RT in complex with α-APA is similar to that found when in complex with nevirapine, another non-nucleoside inhibitor, but there are significant conformational changes relative to an HIV-1 RT/DNA/Fab complex.Conclusion The non-nucleoside inhibitor-binding pocket has a flexible structure whose mobility may be required for effective polymerization, and may be part of a hinge that permits relative movements of two subdomains of the p66 subunit denoted the ‘palm’ and ‘thumb’. An understanding of the structure of the inhibitor-binding pocket, of the interactions between HIV-1 RT and α-APA, and of the locations of mutations that confer resistance to inhibitors provides a basis for structure-based design of chemotherapeutic agents for the treatment of AIDS

Microbial Detoxification of Bifenthrin by a Novel Yeast and Its Potential for Contaminated Soils Treatment

Bifenthrin is one the most widespread pollutants and has caused potential effect on aquatic life and human health, yet little is known about microbial degradation in contaminated regions. A novel yeast strain ZS-02, isolated from activated sludge and identified as Candida pelliculosa based on morphology, API test and 18S rDNA gene analysis, was found highly effective in degrading bifenthrin over a wide range of temperatures (20–40°C) and pH (5–9). On the basis of response surface methodology (RSM), the optimal degradation conditions were determined to be 32.3°C and pH 7.2. Under these conditions, the yeast completely metabolized bifenthrin (50 mg·L−1) within 8 days. This strain utilized bifenthrin as the sole carbon source for growth as well as co-metabolized it in the presence of glucose, and tolerated concentrations as high as 600 mg·L−1 with a qmax, Ks and Ki of 1.7015 day−1, 86.2259 mg·L−1 and 187.2340 mg·L−1, respectively. The yeast first degraded bifenthrin by hydrolysis of the carboxylester linkage to produce cyclopropanecarboxylic acid and 2-methyl-3-biphenylyl methanol. Subsequently, 2-methyl-3-biphenylyl methanol was further transformed by biphenyl cleavage to form 4-trifluoromethoxy phenol, 2-chloro-6-fluoro benzylalcohol, and 3,5-dimethoxy phenol, resulting in its detoxification. Eventually, no persistent accumulative product was detected by gas chromatopraphy-mass spectrometry (GC-MS) analysis. This is the first report of a novel pathway of degradation of bifenthrin by hydrolysis of ester linkage and cleavage of biphenyl in a microorganism. Furthermore, strain ZS-02 degraded a variety of pyrethroids including bifenthrin, cyfluthrin, deltamethrin, fenvalerate, cypermethrin, and fenpropathrin. In different contaminated soils introduced with strain ZS-02, 65–75% of the 50 mg·kg−1 bifenthrin was eliminated within 10 days, suggesting the yeast could be a promising candidate for remediation of environments affected by bifenthrin. Finally, this is the first described yeast capable of degrading bifenthrin

Contrastive prosody and the subsequent mention of alternatives during discourse processing

Linguistic research has long viewed prosody as an important indicator of information structure in intonationally rich languages like English. Correspondingly, numerous psycholinguistic studies have shown significant effects of prosody, particularly with respect to the immediate processing of a prosodically prominent phrase. Although co-reference resolution is known to be influenced by information structure, it has been less clear whether prosodic prominence can affect decisions about next mention in a discourse, and if so, how. We present results from an open-ended story continuation task, conducted as part of a series of experiments that examine how prosody influences the anticipation and resolution of co-reference. Overall results from the project suggest that prosodic prominence can increase or decrease reference to a saliently pitch-accented phrase, depending on additional circumstances of the referential decision. We argue that an adequate account of prosody’s role in co-reference requires consideration of how the processing system interfaces with multiple levels of linguistic representation