2,025 research outputs found
SPIN EXCHANGE IN ELASTIC-E-O2 COLLISIONS
Recent experiments using polarized electron beams have shown that spin-exchange effects for elastic collisions with O2 and NO are much smaller than for Na atoms. We report calculated spin-flip differential cross sections for elastic collisions of polarized electrons with O2 in agreement with experiment. In general, we can attribute large variations of the spin-flip differential cross sections to resonances and interference effects. Such features arising from interference, however, may be washed out in the molecular case due to the average over orientations. Calculations with oriented O2 show strong exchange effects as for Na.68111698170
Low-cost reusable instrumentation for laparoendoscopic single-site nephrectomy: assessment in a porcine model
PURPOSE:
To test different sets of prebent instruments and a new reusable access device for laparoendoscopic single-site (LESS) surgery.
MATERIALS AND METHODS:
Three surgeons with previous experience in LESS performed 12 nephrectomies in six pigs. In all procedures, a multichannel access device (X-CONE) and a 5-mm extra-long telescope were used. Four sets of prebent instruments with different profiles (S-portal) were tested: Standard (one straight scissors and one curved grasper), Cuschieri, Carus, and Leroy set (each of them consisting of two curved instruments with different configurations). Assessment was performed based on both objective (procedure time; time to manage the pedicle; time to free kidney) and subjective parameters (entry/exit of instruments; triangulation; dissection up/down; dissection lateral; retraction; interdependence). The subjective assessment tool used was a Likert type scale (1 = easy to 5 = prohibitive). The access device was assessed by using objective (time to complete insertion of device after skin incision) and subjective (significant air leakage, movement constraint) parameters.
RESULTS:
Time to insertion of the X-CONE was <1 minute in all the cases. Surgeons reported significant insufflant leakage in 58% of cases. The procedure was completed in 10/12 (83%) cases. Mean operative time was 8.3 ± 4.2 minutes, being lower for the Carus group (4.5 min) and higher for the standard group (13 min). Among the different sets, the standard one obtained the best mean scores for all subjective parameters.
CONCLUSIONS:
X-CONE allows easy abdominal access, and its reusable properties represent cost savings for LESS compared with disposable devices. Prebent instruments might also represent attractive low-cost tools for LESS
Low-cost reusable instrumentation for laparoendoscopic single-site nephrectomy: assessment in a porcine model
PURPOSE:
To test different sets of prebent instruments and a new reusable access device for laparoendoscopic single-site (LESS) surgery.
MATERIALS AND METHODS:
Three surgeons with previous experience in LESS performed 12 nephrectomies in six pigs. In all procedures, a multichannel access device (X-CONE) and a 5-mm extra-long telescope were used. Four sets of prebent instruments with different profiles (S-portal) were tested: Standard (one straight scissors and one curved grasper), Cuschieri, Carus, and Leroy set (each of them consisting of two curved instruments with different configurations). Assessment was performed based on both objective (procedure time; time to manage the pedicle; time to free kidney) and subjective parameters (entry/exit of instruments; triangulation; dissection up/down; dissection lateral; retraction; interdependence). The subjective assessment tool used was a Likert type scale (1 = easy to 5 = prohibitive). The access device was assessed by using objective (time to complete insertion of device after skin incision) and subjective (significant air leakage, movement constraint) parameters.
RESULTS:
Time to insertion of the X-CONE was <1 minute in all the cases. Surgeons reported significant insufflant leakage in 58% of cases. The procedure was completed in 10/12 (83%) cases. Mean operative time was 8.3 ± 4.2 minutes, being lower for the Carus group (4.5 min) and higher for the standard group (13 min). Among the different sets, the standard one obtained the best mean scores for all subjective parameters.
CONCLUSIONS:
X-CONE allows easy abdominal access, and its reusable properties represent cost savings for LESS compared with disposable devices. Prebent instruments might also represent attractive low-cost tools for LESS
Effect of Age on the Efficacy and Safety of Once-Daily Single-Inhaler Triple Therapy Fluticasone Furoate/Umeclidinium/Vilanterol in Patients With Chronic Obstructive Pulmonary Disease: A Post Hoc Analysis of the IMPACT Trial
BACKGROUND: In the IMPACT trial, single-inhaler triple therapy fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) reduced moderate/severe exacerbation rates versus FF/VI and UMEC/VI in patients with symptomatic chronic obstructive pulmonary disease (COPD) and a history of exacerbations, with a similar safety profile. Research Question Does age have an effect on trial outcomes? STUDY DESIGN AND METHODS: IMPACT was a Phase III, double-blind, 52-week trial. Patients ≥40 years of age with symptomatic COPD and ≥1 moderate/severe exacerbation in the prior year were randomized 2:2:1 to FF/UMEC/VI 100/62.5/25 mcg, FF/VI 100/25 mcg, or UMEC/VI 62.5/25 mcg. Endpoints assessed by age included annual rate of moderate/severe exacerbations, change from baseline (CFB) in trough forced expiratory volume in 1 second (FEV1), proportion of St George's Respiratory Questionnaire (SGRQ) responders (≥4 units decrease from baseline in SGRQ total score) and safety. RESULTS: The intent-to-treat population comprised 10,355 patients; 4724 (46%), 4225 (41%), and 1406 (14%) were ≤64, 65-74, and ≥75 years of age, respectively. FF/UMEC/VI reduced on-treatment moderate/severe exacerbation rates versus FF/VI (% reduction [95% confidence interval (CI)], ≤64 years: 8% [-1, 16], p=0.070; 65-74 years: 22% [14, 29], p<0.001; ≥75 years 18% [3, 31], p=0.021) and versus UMEC/VI (≤64 years: 16% [7, 25], p=0.002; 65-74 years: 33% [25, 41], p<0.001; ≥75 years 24% [6, 38], p=0.012), with greatest rate reduction seen in the 65-74 and ≥75 years subgroups. Post hoc analyses of CFB in trough FEV1, and proportion of SGRQ responders at Week 52 were significantly greater with FF/UMEC/VI than FF/VI or UMEC/VI in all subgroups. No new safety signals were identified. INTERPRETATION: FF/UMEC/VI reduced the rate of moderate/severe exacerbations and improved lung function and health status versus FF/VI and UMEC/VI irrespective of age for most endpoints, with a similar safety profile. CLINICAL TRIAL REGISTRATION: GSK (CTT116855/NCT02164513)
Stroke Correlates in Chagasic and Non-Chagasic Cardiomyopathies
BACKGROUND: Aging and migration have brought changes to the epidemiology and stroke has been shown to be independently associated with Chagas disease. We studied stroke correlates in cardiomyopathy patients with focus on the chagasic etiology. METHODOLOGY/PRINCIPAL FINDINGS: We performed a cross-sectional review of medical records of 790 patients with a cardiomyopathy. Patients with chagasic (329) and non-chagasic (461) cardiomyopathies were compared. There were 108 stroke cases, significantly more frequent in the Chagas group (17.3% versus 11.1%; p<0.01). Chagasic etiology (odds ratio [OR], 1.79), pacemaker (OR, 2.49), atrial fibrillation (OR, 3.03) and coronary artery disease (OR, 1.92) were stroke predictors in a multivariable analysis of the entire cohort. In a second step, the population was split into those with or without a Chagas-related cardiomyopathy. Univariable post-stratification stroke predictors in the Chagas cohort were pacemaker (OR, 2.73), and coronary artery disease (CAD) (OR, 2.58); while atrial fibrillation (OR, 2.98), age over 55 (OR, 2.92), hypertension (OR, 2.62) and coronary artery disease (OR, 1.94) did so in the non-Chagas cohort. Chagasic stroke patients presented a very high frequency of individuals without any vascular risk factors (40.4%; OR, 4.8). In a post-stratification logistic regression model, stroke remained associated with pacemaker (OR, 2.72) and coronary artery disease (OR, 2.60) in 322 chagasic patients, and with age over 55 (OR, 2.38), atrial fibrillation (OR 3.25) and hypertension (OR 2.12; p = 0.052) in 444 non-chagasic patients. CONCLUSIONS/SIGNIFICANCE: Chagas cardiomyopathy presented both a higher frequency of stroke and an independent association with it. There was a high frequency of strokes without any vascular risk factors in the Chagas as opposed to the non-Chagas cohort. Pacemaker rhythm and CAD were independently associated with stroke in the Chagas group while age over 55 years, hypertension and atrial fibrillation did so in the non-Chagas cardiomyopathies
Olives and olive oil are sources of electrophilic fatty acid nitroalkenes
Extra virgin olive oil (EVOO) and olives, key sources of unsaturated fatty acids in the Mediterranean diet, provide health benefits to humans. Nitric oxide (•NO) and nitrite (NO2-)-dependent reactions of unsaturated fatty acids yield electrophilic nitroalkene derivatives (NO 2-FA) that manifest salutary pleiotropic cell signaling responses in mammals. Herein, the endogenous presence of NO2-FA in both EVOO and fresh olives was demonstrated by mass spectrometry. The electrophilic nature of these species was affirmed by the detection of significant levels of protein cysteine adducts of nitro-oleic acid (NO2-OA-cysteine) in fresh olives, especially in the peel. Further nitration of EVOO by NO2- under acidic gastric digestive conditions revealed that human consumption of olive lipids will produce additional nitro-conjugated linoleic acid (NO2-cLA) and nitro-oleic acid (NO2-OA). The presence of free and protein-adducted NO2-FA in both mammalian and plant lipids further affirm a role for these species as signaling mediators. Since NO2-FA instigate adaptive anti-inflammatory gene expression and metabolic responses, these redox-derived metabolites may contribute to the cardiovascular benefits associated with the Mediterranean diet. © 2014 Fazzari et al
Osmotic modulation of chromatin impacts on efficiency and kinetics of cell fate modulation
Chromatin structure is a major regulator of transcription and gene expression. Herein we explore the use of osmotic modulation to modify the chromatin structure and reprogram gene expression. In this study we use the extracellular osmotic pressure as a chromatin structure and transcriptional modulator. Hyposmotic modulation promotes chromatin loosening and induces changes in RNA polymerase II (Pol II) activity. The chromatin decondensation opens space for higher amounts of DNA engaged RNA Pol II. Hyposmotic modulation constitutes an alternative route to manipulate cell fate decisions. This technology was tested in model protocols of induced pluripotency and transdifferentiation in cells growing in suspension and adherent to substrates, CD34+ umbilical-cord-blood (UCB), fibroblasts and B-cells. The efficiency and kinetics of these cell fate modulation processes were improved by transient hyposmotic modulation of the cell environment
Phenotypic redshifts with self-organizing maps: A novel method to characterize redshift distributions of source galaxies for weak lensing
Wide-field imaging surveys such as the Dark Energy Survey (DES) rely on
coarse measurements of spectral energy distributions in a few filters to
estimate the redshift distribution of source galaxies. In this regime, sample
variance, shot noise, and selection effects limit the attainable accuracy of
redshift calibration and thus of cosmological constraints. We present a new
method to combine wide-field, few-filter measurements with catalogs from deep
fields with additional filters and sufficiently low photometric noise to break
degeneracies in photometric redshifts. The multi-band deep field is used as an
intermediary between wide-field observations and accurate redshifts, greatly
reducing sample variance, shot noise, and selection effects. Our implementation
of the method uses self-organizing maps to group galaxies into phenotypes based
on their observed fluxes, and is tested using a mock DES catalog created from
N-body simulations. It yields a typical uncertainty on the mean redshift in
each of five tomographic bins for an idealized simulation of the DES Year 3
weak-lensing tomographic analysis of , which is a
60% improvement compared to the Year 1 analysis. Although the implementation of
the method is tailored to DES, its formalism can be applied to other large
photometric surveys with a similar observing strategy.Comment: 24 pages, 11 figures; matches version accepted to MNRA
State of emergency medicine in Spain
Spain has universal public health care coverage. Emergency care provisions are offered to patients in different modalities and levels according to the characteristics of the medical complaint: at primary care centers (PCC), in an extrahospital setting by emergency medical services (EMS) and at hospital emergency departments (ED). We have more than 3,000 PCCs, which are run by family doctors (general practitioners) and pediatricians. On average, there is 1 PCC for every 15,000 to 20,000 inhabitants, and every family doctor is in charge of 1,500 to 2,000 citizens, although less populated zones tend to have lower ratios. Doctors spend part of their duty time in providing emergency care to their own patients. While not fully devoted to emergency medicine (EM) practice, they do manage minor emergencies. However, Spanish EMSs contribute hugely to guarantee population coverage in all situations. These EMS are run by EM technicians (EMT), nurses and doctors, who usually work exclusively in the emergency arena. EDs dealt with more than 25 million consultations in 2008, which implies, on average, that one out of two Spaniards visited an ED during this time. They are usually equipped with a wide range of diagnostic tools, most including ultrasonography and computerized tomography scans. The academic and training background of doctors working in the ED varies: nearly half lack any structured specialty residence training, but many have done specific master or postgraduate studies within the EM field. The demand for emergency care has grown at an annual rate of over 4% during the last decade. This percentage, which was greater than the 2% population increase during the same period, has outpaced the growth in ED capacity. Therefore, Spanish EDs become overcrowded when the system exerts minimal stress. Despite the high EM caseload and the potential severity of the conditions, training in EM is still unregulated in Spain. However, in April 2009 the Spanish Minister of Health announced the imminent approval of an EM specialty, allowing the first EM resident to officially start in 2011. Spanish emergency physicians look forward to the final approval, which will complete the modernization of emergency health care provision in Spain
Author Correction: Osmotic modulation of chromatin impacts on efficiency and kinetics of cell fate modulation
Correction to: Scientific Reports https://doi.org/10.1038/s41598-018-25517-2, published online 08 May 2018
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