Lithium- and manganese-rich (LMR) layered-structure materials are very promising cathodes for high energy density lithium-ion batteries. However, their voltage fading mechanism and its relationships with fundamental structural changes are far from being well understood. Here we report for the first time the mitigation of voltage and energy fade of LMR cathodes by improving the atomic level spatial uniformity of the chemical species. The results reveal that LMR cathodes (Li[Li0.2Ni0.2M0.6]O2) prepared by coprecipitation and sol-gel methods, which are dominated by a LiMO2 type R3̅m structure, show significant nonuniform Ni distribution at particle surfaces. In contrast, the LMR cathode prepared by a hydrothermal assisted method is dominated by a Li2MO3 type C2/m structure with minimal Ni-rich surfaces. The samples with uniform atomic level spatial distribution demonstrate much better capacity retention and much smaller voltage fade as compared to those with significant nonuniform Ni distribution. The fundamental findings on the direct correlation between the atomic level spatial distribution of the chemical species and the functional stability of the materials may also guide the design of other energy storage materials with enhanced stabilities.

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BACKGROUND Remote ischemic preconditioning (RIPC) can inhibit recurrent ischemic events effectively in patients with acute or chronic cerebral ischemia. However, it is still unclear whether RIPC can impede ischemic injury after carotid artery stenting (CAS) in patients with severe carotid artery stenosis. METHODS Subjects with severe carotid artery stenosis were recruited in this randomized controlled study, and assigned to RIPC, sham, and no intervention (control) groups. All subjects received standard medical therapy. Subjects in the RIPC and sham groups underwent RIPC and sham RIPC twice daily, respectively, for 2 weeks before CAS. Plasma neuron-specific enolase and S-100B were used to evaluate safety, hypersensitive C-reactive protein, and new ischemic diffusion-weighted imaging lesions were used to determine treatment efficacy. The primary outcomes were the presence of ≥1 newly ischemic brain lesions on diffusion-weighted imaging within 48 hours after stenting and clinical events within 6 months after stenting. RESULTS We randomly assigned 189 subjects in this study (63 subjects in each group). Both RIPC and sham RIPC procedures were well tolerated and completed with high compliance (98.41% and 95.24%, respectively). Neither plasma neuron-specific enolase levels nor S-100B levels changed significantly before and after treatment. No severe adverse event was attributed to RIPC and sham RIPC procedures. The incidence of new diffusion-weighted imaging lesions in the RIPC group (15.87%) was significantly lower than in the sham group (36.51%; relative risk, 0.44; 96% confidence interval, 0.20–0.91; P<0.01) and the control group (41.27%; relative risk, 0.39; 96% confidence interval, 0.21–0.82; P<0.01). The volumes of lesions were smaller in the RIPC group than in the control and sham groups (P<0.01 each). Ischemic events that occurred after CAS were 1 transient ischemic attack in the RIPC group, 2 strokes in the control group, and 2 strokes and 1 transient ischemic attack in the sham group, but these results were not significantly different among the 3 groups (P=0.597). CONCLUSIONS RIPC is safe in patients undergoing CAS, which may be able to decrease ischemic brain injury secondary to CAS. However, the mechanisms and effects of RIPC on clinical outcomes in this cohort of patients need further investigation. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01654666

This is a prospective non-randomized cohort study of 113 consecutive patients to investigate the safety and efficacy of a short-duration intraarterial selective cooling infusion (IA-SCI) targeted into an ischemic territory combined with mechanical thrombectomy (MT) in patients with large vessel occlusion-induced acute ischemic stroke (AIS); 45/113 patients underwent IA-SCI with 350 ml 0.9% saline at 4℃ for 15 min at the discretion of the interventionalist. Key parameters such as vital signs and key laboratory values, symptomatic and any intracranial hemorrhage, coagulation abnormalities, pneumonia, urinary tract infections and mortality were not significantly different between the two groups. Final infarct volume (FIV) was assessed on noncontrast CT performed at three to seven days. After an adjusted regression analysis, the between-group difference in FIV (19.1 ml; 95% confidence interval (CI) 3.2 to 25.2; P = 0.038) significantly favored the IA-SCI group. At 90 days, no differences were found in the proportion of patients who achieved functional independence (mRS 0-2) (51.1% versus. 41.2%, adjusted odd ratio (aOR) 1.9, 95% CI 0.8-2.6, P = 0.192). Combining short-duration IA-SCI with MT was safe. There was a smaller FIV and trend towards clinical benefit that will need to be further evaluated in randomized control trials.

In patients with AIS undergoing ET, tirofiban is not associated with higher sICH, it seems to lead to lower odds of deaths and better odds of long-term functional independence. Further investigations are needed to determine the efficacy of tirofiban in preventing early reocclusion, the underlying mechanisms, and its optimal treatment protocol.

The modification of glass nanopipettes with polyethyleneimines (PEIs) has been successfully achieved by a relatively simple method, and the smallest tip opening is around 3 nm. Thus, in a much wider range of glass pipettes with radii from several nanometers to a few micrometers, the ion current rectification (ICR) phenomenon has been observed. The influences of different KCl concentrations, pH values, and tip radii on the ICR are investigated in detail. The sizes of PEIs have been determined by dynamic light scattering, and the effect of the sizes of PEIs for the modification, especially for a few nanometer-pipettes in radii, is also discussed. These findings systemically confirm and complement the theoretical model and provide a platform for possible selectively molecular detection and mimic biological ion channels.

ObjectiveRemote ischemic conditioning (RIC) has been demonstrated to be safe and feasible for patients with acute ischemic stroke (AIS), as well as for those receiving intravenous thrombolysis. We assessed the safety and feasibility of RIC for AIS patients undergoing endovascular treatment (ET).MethodsWe conducted a pilot study with patients with AIS who were suspected of having an emergent large‐vessel occlusion in the anterior circulation and who were scheduled for ET within 6 hours of ictus. Four cycles of RIC were performed before recanalization, immediately following recanalization, and once daily for the subsequent 7 days. The primary outcome was any serious RIC‐related adverse events.ResultsTwenty subjects, aged 66.1 ± 12.1 years, were recruited. No subject experienced serious RIC‐related adverse events. The intracranial pressure, cranial perfusion pressure, mean arterial pressure, heart rate, middle cerebral artery peak systolic flow velocity, and pulsatility index did not change significantly before, during, or after the limb ischemia (P > 0.1 for all). Of 80 cycles, 71 (89%) were completed before recanalization and 80 (100%) were completed immediately after recanalization; 444 of 560 cycles (78%) were completed within 7 days posttreatment. No patients had to stop RIC because it affected routine clinical managements. Six subjects (30%) experienced intracerebral hemorrhage, which was symptomatic in one case (5%). At the 3‐month follow‐up, 11 subjects (55%) had achieved functional independence, and two subjects (10%) died.Interpretation RIC appears to be safe and feasible for patients with AIS undergoing ET. Investigations are urgently needed to determine the efficacy of RIC in this patient population.

Objective To investigate the feasibility and safety of remote ischemic postconditioning ( RIPC ) in acute ischemic stroke patients after intravenous recombinant tissue plasminogen activator (rt‐ PA ) thrombolysis ( IVT ). Methods We performed a pilot randomized trial involving acute ischemic stroke patients with IVT . The patients were randomized 1:1 to receive RIPC or standard medical therapy. In the RIPC group, the participants underwent instant RIPC within 2 h of IVT , followed by repeated RIPC therapy for 7 days. The feasibility end point was the completion of RIPC and time from the first RIPC to finishing IVT in the RIPC group. The safety end point included tissue and neurovascular injury resulting from RIPC , changes in vital signs, level of plasma myoglobin, any hemorrhagic transformation, and other adverse events. Results Thirty patients (15 RIPC and 15 Control) were recruited after IVT . The mean age was 65.7 ± 10.2 years, with a National Institutes of Health Stroke Scale ( NIHSS ) score of 6.5 (4.0–10.0). The completion rate for RIPC was 97.0%. The mean time from first RIPC to completing IVT was 66.0 (25.0–75.0) min in the RIPC group. One case of hemorrhagic transformation was observed in the RIPC group. No significant difference was found in the level of myoglobin between the two groups ( P > 0.05). Interpretation RIPC is effective and safe for AIS patients after intravenous rt‐ PA thrombolysis.