A novel lithium–oxygen battery exploiting PYR14TFSI–LiTFSI as ionic liquid-based electrolyte medium is reported. The Li/PYR14TFSI–LiTFSI/O2 battery was fully characterized by electrochemical ...impedance spectroscopy, capacity-limited cycling, field emission scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The results of this extensive study demonstrate that this new Li/O2 cell is characterized by a stable electrode–electrolyte interface and a highly reversible charge–discharge cycling behavior. Most remarkably, the charge process (oxygen oxidation reaction) is characterized by a very low overvoltage, enhancing the energy efficiency to 82%, thus, addressing one of the most critical issues preventing the practical application of lithium–oxygen batteries.
The effect of the volume fraction (0.6–8.4%) of the icosahedral phase (I-phase) on the microstructure, texture and mechanical properties of extruded Mg-Zn-Y alloys was examined. During extrusion, the ...eutectic and divorced eutectic I-phase in the cast microstructures was broken into small particles, and the particles were dispersed along the extrusion direction, forming parallel particle bands. The broken I-phase particles promoted grain refinement via a particle-stimulated nucleation mechanism and led to basal texture weakening through dynamic recrystallization. The work hardening rate increased with an increase in the volume fraction of I-phase. However, the strength decreased with an increase in the volume fraction of I-phase due to the texture softening effect. To incorporate the texture softening effect into the Hall-Petch relation, a modified Hall-Petch equation, which simultaneously considers the effects of grain size and texture on strength, was developed using the Schmid factors for basal slip. The proposed equation predicts smaller Hall-Petch slope, friction stress and yield strength with easier activation of basal slip, agreeing with the experimental observations.
•The volume fraction effect of I-phase on the extruded Mg-Zn-Y alloys was examined.•The work hardening rate increased with increasing the volume fraction of I-phase.•The strength decreased with increasing volume fraction of I-phase.•Texture effect on strength was incorporated into the Hall-Petch relation.•Smaller Hall-Petch slope and friction stress with easier activation of basal slip.
Background and purpose
We investigated changes in deep gray matter (DGM) volume and its relationship to cognition and clinical factors in a large cohort of patients with neuromyelitis optica spectrum ...disorder (NMOSD) and compared them with results from multiple sclerosis (MS).
Methods
Brain magnetic resonance imaging (3 Tesla) and clinical data from 91 patients with NMOSD, 52 patients with MS and 44 healthy controls (HCs) were prospectively evaluated. Differences in DGM volumes were compared among groups. The relationships between DGM atrophy and clinical variables were also analysed.
Results
Patients with NMOSD exhibited significantly reduced thalamic volumes compared with HCs (P = 0.029), although this atrophy was less severe than that seen in patients with MS (P < 0.001). DGM atrophy was restricted to the thalamus in NMOSD, but it was broadly distributed in MS. Patients with NMOSD with cognitive impairment (CI) exhibited more severe thalamic atrophy than those with cognitive preservation (P = 0.017) and HCs (P = 0.003), whereas patients with MS with CI revealed DGM atrophy across the entire structure, with the exception of the bilateral pallidum, left hippocampus and amygdala, relative to HCs. The Expanded Disability Status Scale score was correlated with thalamic atrophy in both NMOSD and MS. Patients with NMOSD with brain lesions demonstrated more severe thalamic atrophy than did those without brain lesions and HCs (P < 0.001).
Conclusions
The DGM atrophy was less severe and more selectively distributed in NMOSD than in MS. Thalamic atrophy was associated with clinical disability, including CI, in both NMOSD and MS.
Sweet potato leaf curl virus (SPLCV) infects sweet potato and is a member of the family Geminiviridae (genus Begomovirus). SPLCV transmission occurs from plant to plant mostly via vegetative ...propagation as well as by the insect vector Bemisia tabaci. When sweet potato seeds were planted and cultivated in a whitefly‐free greenhouse, some sweet potato plants started to show SPLCV‐specific symptoms. SPLCV was detected by PCR from all leaves and floral tissues that showed leaf curl disease symptoms. More than 70% of the seeds harvested from SPLCV‐infected sweet potato plants tested positive for SPLCV. SPLCV was also identified from dissected endosperm and embryos. The transmission level of SPLCV from seeds to seedlings was up to 15%. Southern blot hybridization showed SPLCV‐specific single‐ and double‐stranded DNAs in seedlings germinated from SPLCV‐infected seeds. Taken altogether, the results show that SPLCV in plants of the tested sweet potato cultivars can be transmitted via seeds and SPLCV DNA can replicate in developing seedlings. This is the first seed transmission report of SPLCV in sweet potato plants and also, to the authors' knowledge, the first report of seed transmission for any geminivirus.
Aim
Intussusception in adults is rare and requires surgery in most cases. While abdominal laparoscopic surgery (LS) is becoming more popular, there are few reports on the outcomes of adult ...intussusception treated with LS. This study compared the feasibility of LS vs open surgery (OS) for adult intussusception.
Method
We reviewed retrospectively the medical records of adult patients with intussusception from three tertiary hospitals between 2000 and 2016. The patients were divided into LS and OS groups, and their surgical outcomes were compared.
Results
Surgery was indicated in 71 patients with intussusception (41 LS and 30 OS). The median age of the patients was 49.0 and 51.5 years in the LS and OS groups, respectively (P = 0.930). Overall, nine (12.7%) patients had a negative laparotomy or laparoscopy with spontaneous reduction of the intussusception. Conversion to OS from LS was necessary in one patient (2.4%). The operative time and intra‐operative and postoperative complication rates were not significantly different. However, there were more serious complications such as bowel perforation and major vessel injury in the LS group. The patients in the LS group had a shorter time to first food intake and hospital stay vs patients in the OS group (4.0 vs 6.0 days, P < 0.001, and 7.0 vs 10.5 days, P < 0.001, respectively).
Conclusion
LS may be feasible for adult intussusception; there may be more severe intra‐operative complications than in OS.
Glucose oxidase immobilized in mesocellular carbon foam results in a highly sensitive and fast glucose biosensor. The structure of the mesocellular foam (see Figure), with a combination of mesopores ...containing the glucose oxidase (GOx) enzymes and micropores and transport channels, results in high enzyme loading and low mass‐transfer limitations, producing higher catalytic activity and sensitivity than polymer‐matrix‐based GOx glucose sensors.
The cast microstructure of a Mg-13Zn-1.55Y alloy (ZW132) with a high volume fraction of I-phase (7.4%) was refined considerably by severe plastic deformation via high-ratio differential speed rolling ...(HRDSR). Ultrafine grains (0.7–1.3µm) with high angle boundary fractions of 0.48–0.50 were obtained after HRDSR with speed ratios of 2 or 3. The alloy processed at a speed ratio of 3 exhibited high strength and high ductility, with a yield stress of 332MPa and a tensile elongation of 16.3%. The ductility of the rolled ZW alloy was controlled by the work hardening rate, which increased as the amount of I-phase, the degree of refinement of the eutectic I-phase pockets, the degree of dispersion of the broken I-phase particles over the matrix, and the size of the resultant grains increased. A model that considers the contribution of these factors to the work hardening rate was proposed. Grain-size reduction was found to be a major strengthening mechanism. Dispersion of the I-phase particles broken from the eutectic I-phase pockets did not contribute significantly to the material's strength.
We studied respirophasic variation in carotid artery blood flow peak velocity (ΔVpeak-CA) measured by pulsed wave Doppler ultrasound as a predictor of fluid responsiveness in mechanically ventilated ...patients with coronary artery disease.
Forty patients undergoing elective coronary artery bypass surgery were enrolled. Subjects were classified as responders if stroke volume index (SVI) increased ≥15% after volume expansion (6 ml kg−1). The ΔVpeak-CA was calculated as the difference between the maximum and minimum values of peak velocity over a single respiratory cycle, divided by the average. Central venous pressure, pulmonary artery occlusion pressure, pulse pressure variation (PPV), and ΔVpeak-CA were recorded before and after volume expansion.
PPV and ΔVpeak-CA correlated significantly with an increase in SVI after volume expansion. Area under the receiver-operator characteristic curve (AUROC) of PPV and ΔVpeak-CA were 0.75 95% confidence interval (CI) 0.59–0.90 and 0.85 (95% CI 0.72–0.97). The optimal cut-off values for fluid responsiveness of PPV and ΔVpeak-CA were 13% (sensitivity and specificity of 0.74 and 0.71) and 11% (sensitivity and specificity of 0.85 and 0.82), respectively. In a subgroup analysis of 17 subjects having pulse pressure hypertension (≥ 60 mm Hg), PPV failed to predict fluid responsiveness (AUROC 0.70, P=0.163), whereas the predictability of ΔVpeak-CA remained unchanged (AUROC 0.90, P=0.006).
Doppler assessment of respirophasic ΔVpeak-CA seems to be a highly feasible and reliable method to predict fluid responsiveness in mechanically ventilated patients undergoing coronary revascularization.
NCT 01836081.
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