58 research outputs found

    Differential responses of grasses and forbs led to marked reduction in below-ground productivity in temperate steppe following chronic N deposition

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    Enhanced deposition of atmospheric nitrogen (N) has profound impacts on ecosystem processes such as above-ground productivity and community structure in grasslands across the globe. But how N deposition affects below-ground processes of grasslands is less well known. Here, we evaluated the effects of chronic N amendment at a relatively low rate (20 kg ha-1 year-1) on root traits (root productivity, root biomass, root/shoot ratio) in Inner Mongolia steppes by rhizotron and ingrowth core and soil monolith techniques at levels of individual species, functional groups and ecosystem. For 8 years, N amendment suppressed above-ground net primary production (ANPP), photosynthetic rates and root biomass of forbs, but enhanced ANPP and root biomass of grasses. This led to an overall reduction in below-ground productivity of the grassland by 24-33%, while ANPP remained unchanged. Nitrogen amendment acidified soil and subsequently increased extractable soil manganese (Mn) concentration. Nitrogen amendment increased foliar Mn concentrations in forb, but not grass species, leading to a significant inhibition of photosynthetic rates in forb species. Synthesis. These findings highlight the importance of the differentiating responses of plant functional groups to long-term N deposition and the important consequences of these responses for below-ground productivity and long-term soil C sequestration

    Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study

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    A41 Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study In: Addiction Science & Clinical Practice 2017, 12(Suppl 1): A4

    Increasing frailty is associated with higher prevalence and reduced recognition of delirium in older hospitalised inpatients: results of a multi-centre study

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    Purpose: Delirium is a neuropsychiatric disorder delineated by an acute change in cognition, attention, and consciousness. It is common, particularly in older adults, but poorly recognised. Frailty is the accumulation of deficits conferring an increased risk of adverse outcomes. We set out to determine how severity of frailty, as measured using the CFS, affected delirium rates, and recognition in hospitalised older people in the United Kingdom. Methods: Adults over 65 years were included in an observational multi-centre audit across UK hospitals, two prospective rounds, and one retrospective note review. Clinical Frailty Scale (CFS), delirium status, and 30-day outcomes were recorded. Results: The overall prevalence of delirium was 16.3% (483). Patients with delirium were more frail than patients without delirium (median CFS 6 vs 4). The risk of delirium was greater with increasing frailty [OR 2.9 (1.8–4.6) in CFS 4 vs 1–3; OR 12.4 (6.2–24.5) in CFS 8 vs 1–3]. Higher CFS was associated with reduced recognition of delirium (OR of 0.7 (0.3–1.9) in CFS 4 compared to 0.2 (0.1–0.7) in CFS 8). These risks were both independent of age and dementia. Conclusion: We have demonstrated an incremental increase in risk of delirium with increasing frailty. This has important clinical implications, suggesting that frailty may provide a more nuanced measure of vulnerability to delirium and poor outcomes. However, the most frail patients are least likely to have their delirium diagnosed and there is a significant lack of research into the underlying pathophysiology of both of these common geriatric syndromes

    Core-collapse supernovae and the deaths of massive stars

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    In this thesis I present a detailed study of two type IIn supernovae: PTFll iqb and SN 2011jb. I find that PTFll iqb shows complex Ha and H~ profiles, which indicate that the progenitor underwent multiple periods of mass loss . The shells formed by these periods of mass loss are interacting with the ejecta . The measured widths of the narrow components are consistent with a Red Supergiant progenitor. Asymmetric line profiles at late times suggest dust formation. Contrastingly, SN 2011jb appears to be a type Ic supernova which is interacting with a CSM, similarly to SNe 2002ic and SN 2005gj. In these cases the spectra can be modeled as ejecta interacting with a CSM superimposed upon a type la or le spectrum, which appears weak due to the attenuation caused by the dust. I endeavor to conduct a search of all core-collapse supernovae which have exploded within the cryogenic lifetime of Spitzer, within 25Mpc. It is found that type Un SNe were twice as likely to be recovered as other type II supernovae, but due to the low numbers of type Iblc supernovae for which data exists it is not possible. to draw any conclusions about their likelihood of being recovered. The dust which is found in type II supernovae was likely to be caused by a light echo as the ejecta heated the surrounding circumstellar medium. However, dust formation is found to be an equally likely explanation for the presence of dust in other type II supernovae. Lastly, I discuss approaches for furthering our understanding of core-collapse supernovae. These include plans for discovering supernovae more quickly, and studying them more effectively, using surveys such as PESSTO, and pushing the boundaries for the faintest and furthest supernovae we can see using larger telescopes such as the E- ELT.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Combined pharmacotherapy and cognitive behavioral therapy for adults with alcohol or substance use disorders: a systematic review and meta-analysis.

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    Importance: Substance use disorders (SUDs) represent a pressing public health concern. Combined behavioral and pharmacological interventions are considered best practices for addiction. Cognitive behavioral therapy (CBT) is a first-line intervention, yet the superiority of CBT compared with other behavioral treatments when combined with pharmacotherapy remains unclear. An understanding of the effects of combined CBT and pharmacotherapy will inform best-practice guidelines for treatment of SUD. Objective: To conduct a meta-analysis of the published literature on combined CBT and pharmacotherapy for adult alcohol use disorder (AUD) or other SUDs. Data Sources: PubMed, Cochrane Register, MEDLINE, PsychINFO, and Embase databases from January 1, 1990, through July 31, 2019, were searched. Keywords were specified in 3 categories: treatment type, outcome type, and study design. Collected data were analyzed through September 30, 2019. Study Selection: Two independent raters reviewed abstracts and full-text articles. English language articles describing randomized clinical trials examining CBT in combination with pharmacotherapy for AUD and SUD were included. Data Extraction and Synthesis: Inverse-variance weighted, random-effects estimates of effect size were pooled into 3 clinically informative subgroups: (1) CBT plus pharmacotherapy compared with usual care plus pharmacotherapy, (2) CBT plus pharmacotherapy compared with another specific therapy plus pharmacotherapy, and (3) CBT added to usual care and pharmacotherapy compared with usual care and pharmacotherapy alone. Sensitivity analyses included assessment of study quality, pooled effect size heterogeneity, publication bias, and primary substance moderator effects. Main Outcomes and Measures: Substance use frequency and quantity outcomes after treatment and during follow-up were examined. Results: The sample included 62 effect sizes from 30 unique randomized clinical trials that examined CBT in combination with some form of pharmacotherapy for AUD and SUD. The primary substances targeted in the clinical trial sample were alcohol (15 [50%]), followed by cocaine (7 [23%]) and opioids (6 [20%]). The mean (SD) age of the patient sample was 39 (6) years, with a mean (SD) of 28% (12%) female participants per study. The following pharmacotherapies were used: naltrexone hydrochloride and/or acamprosate calcium (26 of 62 effect sizes [42%]), methadone hydrochloride or combined buprenorphine hydrochloride and naltrexone (11 of 62 [18%]), disulfiram (5 of 62 [8%]), and another pharmacotherapy or mixture of pharmacotherapies (20 of 62 [32%]). Random-effects pooled estimates showed a benefit associated with combined CBT and pharmacotherapy over usual care (g range, 0.18-0.28; k = 9). However, CBT did not perform better than another specific therapy, and evidence for the addition of CBT as an add-on to combined usual care and pharmacotherapy was mixed. Moderator analysis showed variability in effect direction and magnitude by primary drug target. Conclusions and Relevance: The present study supports the efficacy of combined CBT and pharmacotherapy compared with usual care and pharmacotherapy. Cognitive behavioral therapy did not perform better than another evidence-based modality (eg, motivational enhancement therapy, contingency management) in this context or as an add-on to combined usual care and pharmacotherapy. These findings suggest that best practices in addiction treatment should include pharmacotherapy plus CBT or another evidence-based therapy, rather than usual clinical management or nonspecific counseling services

    How does brief motivational intervention change heavy drinking and harm among underage young adult drinkers?

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    Objective: This study tested mediating processes hypothesized to explain the therapeutic benefit of an efficacious motivational interview (MI). The constructs of interest were motivation to change, cognitive dissonance about current drinking, self-efficacy for change, perceived young adult drinking norms, future drinking intentions, and the use of protective behavioral strategies. Method: A randomized controlled trial compared the efficacy of a brief MI to a time- and attention-matched control of meditation and relaxation training for alcohol use. Participants were underage, past-month heavy drinkers recruited from community (i.e., non 4-year college or university) settings (N = 167; ages 17-20; 58% female; 61% White). Statistical analyses assessed mechanisms of MI effects on follow up (6-week, 3-month) percent heavy drinking days (HDD) and alcohol consequences (AC) with a series of temporally lagged mediation models. Results: MI efficacy for reducing 6-week HDD was mediated by baseline to postsession changes in the following 3 processes: increasing motivation and self-efficacy, and decreasing the amount these young adults intended to drink in the future. For 6-week AC, MI efficacy was mediated through 1 process: decreased perceived drinking norms. At 3-month follow up, increased cognitive dissonance mediated HDD, but not AC. Further, increased use of certain protective behavioral strategies (i.e., avoidance of and seeking alternatives to drinking contexts) from baseline to 6-weeks mediated both 3-month HDD and AC. Conclusions: Findings suggest that within-session cognitive changes are key mechanisms of MIs effect on short-term alcohol outcomes among community young adults while protective behaviors may be more operative at subsequent follow up
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