Ni-rich materials are appealing to replace LiCoO as cathodes in Li-ion batteries due to their low cost and high capacity. However, there are also some disadvantages for Ni-rich cathode materials such as poor cycling and rate performance, especially under high voltage. Here, we demonstrate the effect of dual-conductive layers composed of LiPO and PPy for layered Ni-rich cathode material. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy show that the coating layers are composed of LiPO and PPy. (NH)HPO transformed to LiPO after reacting with surface lithium residuals and formed an inhomogeneous coating layer which would remarkably improve the ionic conductivity of the cathode materials and reduce the generation of HF. The PPy layer could form a uniform film which can make up for the LiPO coating defects and enhance the electronic conductivity. The stretchy PPy capsule shell can reduce the generation of internal cracks by resisting the internal pressure as well. Thus, ionic and electronic conductivity, as well as surface structure stability have been enhanced after the modification. The electrochemistry tests show that the modified cathodes exhibited much improved cycling stability and rate capability. The capacity retention of the modified cathode material is 95.1% at 0.1 C after 50 cycles, whereas the bare sample is only 86%, and performs 159.7 mAh/g at 10 C compared with 125.7 mAh/g for the bare. This effective design strategy can be utilized to enhance the cycle stability and rate performance of other layered cathode materials.

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The management of bacterial infections is becoming a major clinical challenge due to the rapid evolution of antibiotic resistant bacteria. As an excellent candidate to overcome antibiotic resistance, antimicrobial peptides (AMPs) that are produced from the synthetic and natural sources demonstrate a broad-spectrum antimicrobial activity with the high specificity and low toxicity. These peptides possess distinctive structures and functions by employing sophisticated mechanisms of action. This comprehensive review provides a broad overview of AMPs from the origin, structural characteristics, mechanisms of action, biological activities to clinical applications. We finally discuss the strategies to optimize and develop AMP-based treatment as the potential antimicrobial and anticancer therapeutics.

Our systematic review and meta-analysis showed that Seprafilm could decrease abdominal adhesions after general surgery, which may benefit patients, but could not reduce postoperative intestinal obstruction. At the same time, Seprafilm did increase abdominal abscesses and anastomotic leaks.

A fast-track clinical pathway is designed to streamline patient care delivery and maximize cost effectiveness. It has decreased postoperative length of stay (LOS) and hospital charges for many surgical procedures. However, data on clinical pathways after liver surgery are sparse. This study examined whether use of a fast-track clinical pathway for patients undergoing elective liver resection affected postoperative LOS and hospital charges. A fast-track clinical pathway was developed and implemented by a multidisciplinary team for patients undergoing liver resection. Between July, 2007 and May, 2008, a total of 117 patients underwent elective liver resection: the fast-track clinical pathway (education of patients and families, earlier oral feeding, earlier discontinuation of intravenous fluid, no drains or nasogastric tubes, early ambulation, use of a urinary catheter for less than 24 h and planned discharge 6 days after surgery) was studied prospectively in 56 patients (postpathway group). These patients were compared with the remainder who had usual care (prepathway group). Outcome measures were postoperative LOS, perioperative hospital charges, intraoperative and postoperative complications, mortality, and readmission rate. Among all patients, 69 (59%) had complicating diseases and/or a history of surgery and 24 patients belonged to American Society of Anesthesiologists grade III–IV. Compared with the prepathway group, the postpathway group had a significantly shorter postoperative LOS (7 vs. 11 days, P < 0.01). The average perioperative hospital charges were RMB 26,626 for patients in the prepathway group and only RMB 21,004 for those in the postpathway group (P < 0.05), with no differences in intraoperative and postoperative complications (P = 0.814), mortality (P = 0.606), and readmission rate (P = 0.424). Implementation of the fast-track clinical pathway is an effective and safe method for reducing postoperative LOS and hospital charges for high-risk patients undergoing elective liver resection. The result supports the further development of fast-track clinical pathways for liver surgical procedures.

Prior research suggests an inverse relationship between geographic distance and financial market linkages. In this paper, we examine whether and how cultural distance between countries mitigates this finding. We find that country-pairs exhibit higher linkages if they have smaller cultural distance.The result remains significant to alternative measures of linkage. Finally, the cultural effect seems to be more pronounced for active trading country-pairs than thin-trading country-pairs.

We doped Zr ions in the outer layer of Ni Co Mn (OH) by coprecipitation. The distribution of Zr in the final cathode materials showed a gradient distribution because of ion migration during the thermal treatment. The doped layer was confirmed by using various analysis methods (energy-dispersive X-ray spectroscopy, XRD, X-ray photoelectron spectroscopy, and TEM), which implies that Zr can not only occupy both the transition metal slabs and Li slabs but also form a Li ZrO layer on the surface as a highly ion-conductive layer. The doped Zr in the transition metal slabs can stabilize the crystal structure because of the strong Zr-O bond energy, and the doped Zr in the Li slabs can act as pillar ions to improve the structural stability and reduce cation mixing. The gradient doping can take advantage of the "pillar effect" and restrain the "blocking effect" of the pillar ions, which reduces irreversible capacity loss and improves the cycling and rate performance of the Ni-rich cathode materials. The capacity retention of the modified sample reached 83.2 % after 200 cycles at 1C (200 mA g ) at 2.8-4.5 V, and the discharge capacity was up to 164.7 mAh g at 10C. This effective strategy can improve the structure stability of the cathode material while reducing the amount of non-electrochemical active dopant because of the gradient distribution of the dopant. In addition, the highly ion-conductive layer of Li ZrO on the surface can improve the rate performance of the cathode.

A modified Ni-rich Li[NiCoMn]O cathode material with exposed {010} planes is successfully synthesized for lithium-ion batteries. The scanning electron microscopy images have demonstrated that by tuning the ammonia concentration during the synthesis of precursors, the primary nanosheets could be successfully stacked along the [001] crystal axis predominantly, self-assembling like multilayers. According to the high-resolution transmission electron microscopy results, such a morphology benefits the growth of the {010} active planes of final layered cathodes during calcination treatment, resulting in the increased area of the exposed {010} active planes, a well-ordered layer structure, and a lower cation mixing disorder. The Li-ion diffusion coefficient has also been improved after the modification based on the results of potentiostatic intermittent titration technique. As a consequence, the modified Li[NiCoMn]O material exhibits superior initial discharges of 201.6 mA h g at 0.2 C and 185.7 mA h g at 1 C within 2.8-4.3 V (vs Li/Li), and their capacity retentions after 100 cycles reach 90 and 90.6%, respectively. The capacity at 10 C also increases from 98.3 to 146.5 mA h g after the modification. Our work proposes a novel approach for exposing high-energy {010} active planes of the layered cathode material and again confirms its validity in improving electrochemical properties.