253 research outputs found
Alcohol and tobacco consumption, personality, and cybervictimization among adolescents
Cyberbullying has emerged as a public health problem. Personality may play an important role in substance use and cybervictimization. The aim of this study was to examine whether tobacco and alcohol consumption and personality traits are associated with cybervictimization in Spanish adolescents. A cross-sectional study was conducted with 765 secondary students (aged 14–16) from 16 secondary schools in Spain. Participants completed a questionnaire assessing sociodemographic characteristics; tobacco and alcohol consumption; cybervictimization (Garaigordobil Scale); and personality traits (Big Five Questionnaire). A logistic regression model controlling for sex, age, parental education and personality traits was used to determine the independent associations and interactions between tobacco and alcohol consumption and cybervictimization. The results indicate that a total of 305 adolescents (39.9%) reported that they were cyberbullied in the past year. Girls were more likely to be cyberbullied than boys. Cybervictims had a significantly greater monthly alcohol consumption (OR = 1.51; 95% CI = 1.05–2.15), higher scores for extraversion (OR = 1.31; 95% CI = 1.06–1.63) and emotional instability (OR = 1.53; 95% CI = 1.27–1.83); as well as lower scores for conscientiousness (OR = 0.78; 95% CI = 0.63–0.95). These results suggest that personality traits and alcohol consumption are independently associated with cybervictimization. Our study suggests the existence of underlying common personality factors for cybervictimization and alcohol and tobacco use.Instituto de Salud Carlos III | Ref. PI12/0181
Composición cualitativa del fitoplancton de los embalses de Cúber y Gorg Blau (Serra de Tramuntana, Mallorca). I. Cyanophyta y Dinophyta
Abstract not availabl
Palladium-catalyzed intramolecular carbene insertion into C(sp3)-H bonds
A palladium‐catalyzed carbene insertion into C(sp3)−H bonds leading to pyrrolidines was developed. The coupling reaction can be catalyzed by both Pd0 and PdII, is regioselective, and shows a broad functional group tolerance. This reaction is the first example of palladium‐catalyzed C(sp3)−C(sp3) bond assembly starting from diazocarbonyl compounds. DFT calculations revealed that this direct C(sp3)−H bond functionalization reaction involves an unprecedented concerted metalation-deprotonation step
Facile synthesis of azocino[4,3-b]indoles by ring-closing metathesis
The azocino[4,3-b]indole system, tricyclic substructure of the indole alkaloids apparicine and ervaticine, is efficiently assembled by ring-closing metathesis of 2-allyl-3-(allylaminomethyl)indoles. The metathesis sites are introduced into the indole nucleus by reductive amination of a 3-formyl derivative with allylamine, followed by a-lithiation with subsequent electrophilic trapping with acrolein
Rapid Synthesis of the Ervitsine Alkaloid Skeleton by a Sequential RCM-Heck Cyclization Approach
An efficient approach to the bridged framework of the indole alkaloid ervitsine, featuring a ring-closing metathesis reaction from a 2,3-disubstituted indole followed by a vinyl halide Heck cyclization upon the resulting cycloheptene ring, is described
Sequential ring-closing metathesis-vinyl halide Heck cyclization reactions: access to the tetracyclic ring system of ervitsine
A chemoselective indole-templated ring-closing metathesis is used to assemble the cyclohepta[b]indole substructure of the indole alkaloid ervitsine. A subsequent intramolecular Heck coupling of the resulting alkene functionality with an amino-tethered vinyl halide accomplishes the closure of the unique 2- azabicyclo[4.3.1]decane framework of the alkaloid with concomitant incorporation of the exocyclic Eethylidene substituent
Exploration of Ring‐Closing Enyne Metathesis for the Synthesis of Azonino[5,4‐b]indoles
The use of the ring‐closing enyne metathesis (RCEYM) as a methodology for the synthesis of the azonino[5,4‐b]indole system, featuring the tricyclic substructure of the alkaloids cleavamine and quebrachamine, has been explored. Three series of enyne substrates were studied for their compatibility with the RCEYM reaction. In addition to the usual substrates bearing either a terminal or an internal alkyne, for the first time enynes with an alkynyl halide moiety were also considered. Although the metathesis cyclization allowed for assembly of the azoninoindole nucleus in all three series, an effective catalytic cycle was only noted for internal alkyne substrates. On the basis of the experimental results, the "yne‐then‐ene" pathway seems to be the mechanism at play in these reactions
Palladium catalysis in intramolecular carbene C-H insertion of α-diazo-α-(methoxycarbonyl)acetamides to form β-lactams
The intramolecular carbene C-H insertion of α‐diazo‐α‐(methoxycarbonyl)acetamides leading to β‐lactams is effectively catalyzed by palladium complexes. It is found that although Pd0 catalysts typically produce mixtures of β‐lactams together with Buchner‐type reaction products, the use of PdII catalysts results in highly chemoselective transformations. According to DFT calculations, this insertion reaction occurs stepwise and involves an unprecedented PdII‐promoted Mannich‐type reaction through a metallacarbene‐induced zwitterionic intermediate
Recommended from our members
Appraising the quality standard underpinning international clinical practice guidelines for the selection and care of vascular access devices: a systematic review of reviews
OBJECTIVE: Catheter-related bloodstream infections are one of the most important adverse events for patients. Evidence-based practice embraces interventions to prevent and reduce catheter-related bloodstream infections in patients. At present, a growing number of guidelines exist worldwide. The purpose of the study was to assess clinical practice guidelines for peripheral and central venous access device care and prevention of related complications.
DESIGN: Systematic review of clinical practice guidelines: We conducted a search of the literature published from 2005 to 2018 using Medline/PubMed, Embase, CINAHL, Ovid, ScienceDirect, Scopus and Web of Science. We also evaluated grey literature sources and websites of organisations that compiled or produced guidelines. Guideline quality was assessed with the Appraisal of Guidelines for Research and Evaluation, Second Edition tool by three independent reviewers. Cohen's kappa coefficient was used to evaluate the concordance between reviewers.
RESULTS: We included seven guidelines in the evaluation. The concordance between observers was substantial, K=0.6364 (95% CI 0.0247 to 1.2259). We identified seven international guidelines, which scored poorly on crucial domains such as applicability (medium 39%), stakeholder involvement (medium 65%) and methodological rigour (medium 67%). Guidelines by Spanish Health Ministry and UK National Institute for Health and Care Excellence presented the highest quality.
CONCLUSIONS: It is crucial to critically evaluate the validity and reliability of clinical practice guidelines so the best, most context-specific document is selected. Such choice is a necessary prior step to encourage and support health organisations to transfer research results to clinical practice. The gaps identified in our study may explain the suboptimal clinical impact of guidelines. Such low adoption may be mitigated with the use of implementation guides accompanying clinical documents
Automated assessment of movement impairment in Huntington's disease
Quantitative assessment of movement impairment in Huntington’s disease (HD) is essential to monitoring of disease progression. This study aimed to develop and validate a novel low cost, objective automated system for the evaluation of upper limb movement impairment in HD in order to eliminate the inconsistency of the assessor and offer a more sensitive, continuous assessment scale. Patients with genetically confirmed HD and healthy controls were recruited to this observational study. Demographic data including age (years), gender and Unified Huntington’s Disease Rating Scale Total Motor Score (UHDRS-TMS) were recorded. For the purposes of this study a modified upper limb motor impairment score (mULMS) was generated from the UHDRS-TMS. All participants completed a brief, standardized clinical assessment of upper limb dexterity whilst wearing a tri-axial accelerometer on each wrist and on the sternum. The captured acceleration data were used to develop an automatic classification system for discriminating between healthy and HD participants and to automatically generate a continuous Movement Impairment Score (MIS) that reflected the degree of the movement impairment. Data from 48 healthy and 44 HD participants was used to validate the developed system, which achieved 98.78% accuracy in discriminating between healthy and HD participants. The Pearson correlation coefficient between the automatic MIS and the clinician rated mULMS was 0.77 with a p-value < 0.01. The approach presented in this study demonstrates the possibility of an automated objective, consistent and sensitive assessment of the HD movement impairment
- …