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： Lithium-ion batteries (LIBs) play a vital role in portable electronic products, transportation and large-scale energy storage. However, the electrochemical performance of LIBs deteriorates severely at low temperatures, exhibiting significant energy and power loss, charging difficulty, lifetime degradation, and safety issue, which has become one of the biggest challenges for LIBs. This article aims to review challenges and limitations of the battery chemistry in low-temperature environments, as well as the development of low-temperature LIBs from cell level to system level. This review introduces feasible solutions to accelarate low-temperature kinetics by increasing the inherent reactivity from cell design and improving the external reaction temperature from heating techniques. In addition, real-time and accurate monitoring of the battery temperature for the battery thermal management, as well as the optimization of charging protocols and the online lithium-plating monitoring in battery management systems are outlined. In general, a systematic review of low-temperature LIBs is conducted in order to provide references for future research.

Due to the complexity of Crohn's disease (CD), it is difficult to predict disease course with a single stratification factor or biomarker. A logistic regression (LR) model has been proposed by Guizzetti et al to stratify patients with CD-related surgical risk, which could help decision-making on disease treatment. However, there are no reports on relevant studies on Chinese population. The aim of the study is to present and validate a novel surgical predictive model to facilitate therapeutic decision-making for Chinese CD patients. Data was extracted from retrospective full-mode electronic medical records, which contained 239 CD patients and 1524 instances. Two sub-datasets were generated according to different attribute selection strategies, both of which were split into training and testing sets randomly. The imbalanced data in the training sets was addressed by synthetic minority over-sampling technique (SMOTE) algorithm before model development. Seven predictive models were employed using 5 popular machine learning algorithms: random forest (RF), LR, support vector machine (SVM), decision tree (DT) and artificial neural networks (ANN). The performance of each model was evaluated by accuracy, precision, F1-score, true negative (TN) rate, and the area under the receiver operating characteristic curve (AuROC). The result revealed that RF outperformed all other baseline models on both sub-datasets. The 10 leading risk factors for CD-related surgery returned from RF for attribute ranking were changes of radiology, presence of a fistula, presence of an abscess, no infliximab use, enteroscopy findings, C-reactive protein, abdominal pain, white blood cells, erythrocyte sedimentation rate and platelet count. The proposed machine learning model can accurately predict the risk of surgical intervention in Chinese CD patients, which could be used to tailor and modify the treatment strategies for CD patients in clinical practice.

Sluggish evolution of lithium ions’ solvation sheath induces large charge-transfer barriers and high ion diffusion barriers through the passivation layer, resulting in undesirable lithium dendrite formation and capacity loss of lithium batteries, especially at low temperatures. Here, an ion-dipole strategy by regulating the fluorination degree of solvating agents is proposed to accelerate the evolution of the Li+ solvation sheath. Ethylene carbonate (EC)-based fluorinated derivatives, fluoroethylene carbonate (FEC) and di-fluoro ethylene carbonate (DFEC) are used as the solvating agents for a high dielectric constant. As the increase of the fluorination degree from EC to FEC and DFEC, the Li+-dipole interaction strength gradually decreases from 1.90 to 1.66 and 1.44 eV, respectively. Consequently, the DFEC-based electrolyte displays six times faster ion desolvation rate than that of a non-fluorinated EC-based electrolyte at −20 °C. Furthermore, LiNi0.8Co0.1Mn0.1O2||lithium cells in a DFEC-based electrolyte retain 91% original capacity after 300 cycles at 25 °C, and 51% room-temperature capacity at −30 °C. By bridging the gap between the ion-dipole interactions and the evolution of Li+ solvation sheath, this work provides a new technique toward rational design of electrolyte engineering for low-temperature lithium batteries.

To study the correlation between MRI apparent diffusion coefficient (ADC) and expression of Ki-67 in gastric cancers, and to investigate the application of ADC value in diagnosing the malignance of gastric cancer.A retrospective cohort analysis was performed on 87 gastric cancer patients who received MRI examination and radical resection at Zhejiang Provincial Hospital of Traditional Chinese Medicine from November 2014 to August 2015. All the postoperative resected samples were confirmed as gastric cancer. Preoperative MRI examination was performed by using Siemens 3.0-T Verio MRI with following parameters: section thickness 3 mm, gap 1 mm, matrix 182×320, field of view 40 cm. Plain scan was followed by T1-weighted fat suppression technique VIBE 3D(TR3.92/TE1.39,90degree) scans at arterial phase (the 30th second), portal venous phase (the 60th second), lag period (the 90th second), axial planes and coronal planes (the 180th second), and sagittal planes (the 210th second), respectively. ADC value of tumor was measured at b-factor of 800 s/mmIrregular thickening of the gastric wall and inhomogeneous enhancement of the tumor after injection of the contrast material appeared in gastric cancer. Gastric cancer tissue presented hyperintensity and normal gastric wall presented isointensity in DWI image (b=800 s/mmThe ADC value of gastric cancer can reflect the level of tumor differentiation, and is negatively correlated with Ki-67 expression in cancer tissues.

Nanochannel arrays with the same nanochannel density but different nanochannel diameters in different areas in one piece of anodic alumina membrane had been created. SEM observations on one piece of this type of anodic alumina membrane show that the nanochannel diameters radially decrease from 80 nm to 60 nm and to 40 nm along the radial direction. Therefore, using this type of membrane as a template, ordered Ag nanowire arrays with the same nanowire density but with diameters decreasing radially were obtained by electrodeposition. SEM and TEM images taken of different areas of the Ag nanowire arrays show that we can control the growth of aligned Ag nanowires with different diameters in a single process at the same time. Using this type of template in combination with other fabrication techniques, nanometer-scale fibrils, rods, wires, and tubules of metal, semiconductors, carbon, and other materials with same density but different diameters in different areas can be fabricated. The simultaneous integration of ordered nanowire structures with different diameters embedded in a single anodic alumina membrane could be useful in nanodevice manufacture as well as electronics, optoelectronics and magnetics.

A laminated micropolarizer of Pb nanowire arrays was fabricated within an anodic alumina membrane (AAM) by anodization of the pure Al foil and subsequent electrodeposition of Pb. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, selected-area electron diffraction, and high-resolution electron microscopy investigations reveal that the ordered Pb nanowires are essentially single crystal, and have an average diameter of 40 nm. Spectrophotometry measurements show that the Pb nanowire arrays embedded in AAM can only transmit polarized light vertical to the wires. An extinction ratio of 17 to 18 dB and an average insertion loss of 0.4 dB cm–1 in the wavelength range of 1 to 2.2 μm were obtained, respectively. Therefore, these Pb nanowire/AAM composites can be used as a wire grid type micropolarizer.