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The solid–liquid (S–L) phase separation occurs in the polyethylene (PE)/liquid paraffin (LP) blend, which exhibits different characteristics for the molecular weight of PE. Herein, we have studied the S–L phase separation process of PE-500 (molecular weight of 5,000,000)/PE-60 (molecular weight of 600,000)/LP melts by the hot-stage-optical device. It is found that the clarification temperature and cloud temperature of PE-500/PE-60/LP blend decreased with the addition of PE-60. The isothermal crystallization behavior of these ternary blends is explored further using differential scanning calorimetry (DSC). According to the analysis results of Avrami equation and Arrhenius equation, the exponent n increases from 1.23 to 2.42 at higher temperature, indicating that the melt with high PE-60 content have a growth pattern between two and three dimensions, which could lead to larger pore. The activation energy at high temperature increases from 738.568 to 1321.259 kJ / mol with enhancing PE-60 content, while the activation energy decreases from 209.689 to 36.608 kJ / mol at lower temperature. It demonstrates that PE-60 content is not conducive to nucleation at high temperatures, but in favor of growth at low temperature. We believe the pore structure of PE microporous membrane may be controlled by different ratios of PE-500/PE-60 and crystallization temperature. [ABSTRACT FROM AUTHOR]

The separators have an impact on the performance of lithium-based battery, whereas traditional polyolefin separators are hard to retain enough liquid electrolyte for its nonpolar surface and lead to battery performance degradation. In this experimental work, we have tried to activate polyethylene (PE) separator by γ-ray irradiation with different doses. According to these results of FTIR-ATR, the contact angle and mechanical test, it is concluded that γ-ray irradiation would get the PE long chains broken and oxidized furtherly. Therefore, these irradiated separators show a higher surface energy and inferior mechanical strength than pristine PE separator. For comprehensive consideration, the PE-20 (irradiated by the dose of 20 kGy) separator is selected to evaluate the electrochemical performance. The LiCoO2 cells with PE-20 separators have a better cyclic stability than that of PE separator for lower interfacial resistance and stronger affinity to liquid electrolyte. Especially in the unsymmetrical rate performance test, the cells based on PE-20 separator have higher discharge capacity. It demonstrates that this method of γ-ray irradiation could be used to modify PE separator for enhancing battery performance. [ABSTRACT FROM AUTHOR]

In order to solve the shortcomings of the current traditional commercial polyolefin microporous membranes with worse thermostability at high temperature, polyimide (PI) nanofiber membranes prepared by electrospinning are promising separators for lithium ion batteries that operate at high temperatures. This preparation includes the forming process of poly(amic acid) (PAA) fibers membrane and thermal-imidization process. In this study, we design the experiment of thermal-imidization for PAA fibers to improve the mechanical strength and the electrochemical performance of the obtained PI nanofiber membrane. It is found that the degradation phenomenon and the crosslinking function occur after the imidization during the heat treatment. The mechanical strength of PI nanofiber membrane gets improved with new crosslinking system after being heat-treated at 350 °C. LiCoO2/Li cells based on such PI nanofiber membranes exhibit excellent cycle performance (300 cycles) and rate performance (even at high rates of 6 C), better than those employing polyolefin microporous membranes. During the heat treatment of polyamic acid, a thermal imidization process will occur. At the same time, different heat treatment temperatures will lead to differences in the degree of imidization and the structure of the fiber membrane material. It is important to understand the thermal imidization process. The effect of thermal imidization temperature on the performance of the electrospun polyimide lithium ion battery separator is studied. The experimental results show that although the degree of imidization is decreased by the heat treatment at 350 °C, it has better cycle performance (300 circles) and rate performance (even at high rates of 6 C). [ABSTRACT FROM AUTHOR]

Ultra-high-molecular-weight polyethylene (UHMWPE) microporous membrane is generally prepared by thermally induced phase separation process. The phase separation process is closely related to the cooling process in practical production. In this paper, the phase separation temperature of UHMWPE/liquid paraffin blends was explored by the hot-stage-optical device and differential scanning calorimeter (DSC), and the result showed that the temperature was about 105–125 °C. The effects of cooling condition and crystallization ability of UHMWPE on the separation process of the blends were also investigated by DSC. The results showed that the phase separation was affected by the cooling rates rather than the initial cooling temperature. And the crystallization of UHMWPE was mainly limited by the nucleating at a low cooling rate, which could form larger porous structure. In a word, it should be inspirational for the actual production of the UHMWPE microporous membrane. The solid–liquid phase separation will occur in the cooling process of UHMWPE/LP blends, which is driven by the external temperature difference. It is significant to understand the phase separation process. In this paper, the effects of the melting properties and cooling condition on phase separation process were investigated, the S–L phase separation range is at 105–125 °C, and the speed of phase separation is mainly related to the external temperature difference and the UHMWPE content. It could be inspirational for actual production of the UHMWPE membrane with more uniform pore structure. [ABSTRACT FROM AUTHOR]

Purpose: A new in vivo rabbit model was developed to investigate the effects of shear force on intervertebral disc (IVD). Methods: Japanese white rabbits ( n = 38) were used for this study. The L4/5 discs in Group A ( n = 10) were subjected to a constant shear force (50 N) using a custom-made external loading device for 1 month; in Group B ( n = 10) for 2 months; whereas in Group C ( n = 10), loading device was attached to the spine but the discs remained unloaded. Group D ( n = 8) was a non-operated intact control group. After loading, the loading devices were taken out and the animals were given X-ray and MRI examination. After X-ray and MRI examination, the animals were euthanized for histological analysis. Results: After 1 and 2 months of loading, radiographic findings showed significant disc height narrowing in L4/5 discs of the animals in loading groups, and slight lumbar spondylolisthesis in some animals of Group B. MRI showed a significant decrease in nucleus pulposus (NP) area and signal intensity from T2-weighted images. Histologically, loss of normal NP cells and disorganization of the architecture of the annulus occurred, and proteoglycan stain decreased. Conclusions: The results of this study suggest that disc degeneration can be induced by hyper-physiological shear loading in the rabbit IVD. Long-term shear loading may result in structural disc failure inducing lumbar spondylolisthesis and progressive disc degeneration, which, however, has to be proven by further studies. [ABSTRACT FROM AUTHOR]

Purpose: To establish reference data on the dimensions of C2 lamina to guide the use of translaminar screws with Wright's technique and a modified technique for pediatric patients in different age groups.Methods: 113 pediatric patients were divided into six age groups, and their cervical vertebrae were studied on CT scans. Laminar height, width, length and screw angle were measured. Statistical analysis was performed using Student t tests, Pearson's correlation and linear regression analysis.Results: Mean laminar height was 10.95 ± 2.81 mm, and mean width was 6.01 ± 0.90 mm. For Wright's technique, mean laminar length was 30.65 ± 3 mm, and the screw angle was 56.02° ± 3.62°. For the modified technique, mean laminar length was 22.07 ± 2.38 mm, and the screw angle was 67.40° ± 3.39°. 95.6% (108/113) of the children could insert a screw into the lamina (laminar width ≥ 4.5 mm), 72.6% (82/113) could accept bilateral translaminar screws (laminar width ≥ 4.5 mm and laminar height ≥ 9 mm).Conclusion: Our investigation provides insight into the anatomy of C2 lamina in six pediatric age groups. Compared to adults, the benefits of C2 translaminar screws fixation are more obvious in the pediatric spine which has a large C2 lamina. Compared to Wright's technique, the modified technique should insert a screw with bigger insert angle and shorter screw length. [ABSTRACT FROM AUTHOR]

Purpose: To establish reference data on the dimensions of C2 lamina to guide the use of translaminar screws with Wright's technique and a modified technique for pediatric patients in different age groups. Methods: 113 pediatric patients were divided into six age groups, and their cervical vertebrae were studied on CT scans. Laminar height, width, length and screw angle were measured. Statistical analysis was performed using Student t tests, Pearson's correlation and linear regression analysis. Results: Mean laminar height was 10.95 ± 2.81 mm, and mean width was 6.01 ± 0.90 mm. For Wright's technique, mean laminar length was 30.65 ± 3 mm, and the screw angle was 56.02° ± 3.62°. For the modified technique, mean laminar length was 22.07 ± 2.38 mm, and the screw angle was 67.40° ± 3.39°. 95.6 % (108/113) of the children could insert a screw into the lamina (laminar width ≥4.5 mm), 72.6 % (82/113) could accept bilateral translaminar screws (laminar width ≥4.5 mm and laminar height ≥9 mm). Conclusion: Our investigation provides insight into the anatomy of C2 lamina in six pediatric age groups. Compared to adults, the benefits of C2 translaminar screws fixation are more obvious in the pediatric spine which has a large C2 lamina. Compared to Wright's technique, the modified technique should insert a screw with bigger insert angle and shorter screw length. [ABSTRACT FROM AUTHOR]

Adult-onset Still's disease (AOSD), as a category of connective tissue diseases, has about 5∼9% of fever of unknown origin (FUO) cases. Diagnosis of AOSD was challenging because of its nonspecific characteristics. The present study analyzed clinical manifestations and laboratory findings in a series of patients with AOSD from eastern China. Medical records of 61 patients admitted with FUO and with a discharge diagnosis of AOSD were retrospectively evaluated and analyzed with special focus on clinical manifestations and laboratory findings. Compared with previous reports, most features of our patients had a similar incidence rate. Rash (79%), arthralgia (80%), and sore throat (84%) were the most frequent clinical manifestations in our series. Leukocytosis (80%), elevated ESR (98%) and CRP (100%), negative ANA (90%) and RF (93%), and high ferritin level (94%) were the most sensitive laboratory findings in our patients. AOSD was not a rare reason of FUO in eastern China. Fever, arthralgia, rash, sore throat, leukocytosis, neutrophilia, elevated ESR and CRP, negative ANA and RF, and high ferritin level were the most common clinical features in our series. The lack of highly specific characteristic makes the diagnosis of AOSD difficult compared with other diseases in FUO. [ABSTRACT FROM AUTHOR]

Background and Aim: Synaptic plasticity plays an important role in affecting the intensity of visceral reflex. It may also be involved in the development of visceral hypersensitivity. The aim of this study was to investigate the role of synaptic plasticity on visceral hypersensitivity of rats infected by Trichinella spiralis.Methods: Thirty male Sprague-Dawley (SD) rats were randomly divided into control, acute, and chronic infection groups, and were investigated at 1 week after adaptive feeding and at 2 and 8 weeks post infection (PI) by oral administration of 1 ml phosphate-buffered saline (PBS) containing 8,000 Trichinella spiralis larvae. Visceral sensitivity was evaluated by electromyography (EMG) recording during colorectal distension. Intestinal inflammation was observed by hematoxylin-eosin (HE) staining. Synaptic ultrastructure parameters, such as postsynaptic density (PSD) length, synaptic cleft, and number of synaptic vesicles, were examined by transmission electron microscopy (TEM). The expression of protein associated with synaptic plasticity, including postsynaptic density-95 (PSD-95), synaptophysin, calbindin-28 K, N-methyl-D-aspartate receptor-1 (NMDA-R1), alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor (AMPA-R), and glial cell line-derived neurotrophic factor (GDNF), were analyzed by Western blot.Results: (1) Visceral hypersensitivity was noted in the chronic infection group, although the inflammation was nearly eliminated (P<0.05). Severe inflammation and downregulation of visceral sensitivity were observed in the acute infection group (P<0.05). (2) There were many more synaptic vesicles and longer PSD in the chronic infection group than in the control group (P<0.05, respectively). However, in comparison with control rats, disappearance of mitochondria cristae in the synapses, and decrease of synaptic vesicles and length of PSD were observed in the acute infection group. There was no significant difference in width of synaptic cleft among the three groups. (3) Compared with the control, the expression of proteins associated with synaptic plasticity was significantly upregulated during chronic infection phase (P<0.05), and downregulated during acute infection phase.Conclusion: Synaptic plasticity was observed in SD rats infected by Trichinella spiralis and was associated with visceral sensitivity, which suggests that it may play an important role in the formation of visceral hypersensitivity. [ABSTRACT FROM AUTHOR]

With the increasing incidence of cardiovascular events, especially for cardiac arrest and sudden death, the importance of external defibrillator has been greatly recognized. While the current electrodes used in external defibrillator are mainly rigid electrode generating large resistance in the interface between the electrode and the electrical stimulation is unable to be effectively delivered to the target area and even cauterize the skin. In this work, we conducted the adhesive patterning liquid metal flexible electrode for external defibrillator and ECG measurement, the COSMOL simulation analysis of ventricular fibrillation model suggested that the LM flexible electrode can assure the same current distribution and energy delivery, meanwhile requiring less energy input and avoiding skin burn. Furthermore, we verified the better signal stability and certain robustness to motion of liquid metal flexible electrode when measuring electrocardiogram (ECG) compared to the conventional AgCI electrode. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a highly prevalent and chronic disorder that is associated with a substantial social and economic burden. Itaconate, as an important regulator of cellular inflammation, is a metabolite synthesised by an enzyme encoded by immune-responsive gene 1. However, there are few studys regarding the effects of itaconate on OA. Here, we show the effect of the cell-permeable itaconate derivative 4-octyl itaconate (OI) on OA. OI attenuates the chondrocyte apoptosis induced by interleukin 1β (IL-1β) in vitro, indicating that OI protect chondrocytes against apoptosis. Moreover, OI ameliorates the chondrocyte autophagy inhibition induced by IL-1β via the inhibition of PI3K/AKT/mTOR signalling pathway. Finally, OI enhances autophagy and reduces cartilage degradation in a rat model of OA established by destabilization of medial meniscus (DMM). In summary, our findings reveal that OI is involved in regulating the progression of OA. The above results shed light on the treatment of OA. 4-octyl itaconate (OI) attenuates chondrocyte apoptosis and ameliorates cartilage degradation and defection of autophagy induced by IL-1 β via the PI3K/AKT/mTOR pathway. OI improved the autophagy and reduced the inflammation of rat models of osteoarthritis. [ABSTRACT FROM AUTHOR]

Flexible electronics have grown rapidly due to their potential for portable physiological monitoring and treatment in recent years, such traditional flexible electronic devices with flexible features are usually fabricated on a very thin substrate, which do not directly contact the skin. This may generate large coupling impedance with the skin and a high signal noise for a sensitive detection of weak physiological signals. In this article, we presented a new conceptual flexible bioelectrode based on liquid metal and built an electrical model to illustrate the electrode–skin interface and tested the model on electrode–skin conductivity. It shows that the liquid metal flexible electrode closely attached to the curved surface can bring uniform potential and electric field distribution under skin, and the interface has the smallest impedance, The present work revealed the potential of such flexible bioelectrode in many aspects of biomedical use, such as electronic skin, sensitive electrocardiogram monitoring, acute ventricular defibrillation and so on. [ABSTRACT FROM AUTHOR]

Background: Some neuropsychological diseases are associated with abnormal thiamine metabolism, including Korsakoff–Wernicke syndrome and Alzheimer's disease. However, in vivo detection of the status of brain thiamine metabolism is still unavailable and needs to be developed. Methods: A novel PET tracer of 18F-deoxy-thiamine was synthesized using an automated module via a two-step route. The main quality control parameters, such as specific activity and radiochemical purity, were evaluated by high-performance liquid chromatography (HPLC). Radiochemical concentration was determined by radioactivity calibrator. Metabolic kinetics and the level of 18F-deoxy-thiamine in brains of mice and marmosets were studied by micro-positron emission tomography/computed tomography (PET/CT). In vivo stability, renal excretion rate, and biodistribution of 18F-deoxy-thiamine in the mice were assayed using HPLC and γ-counter, respectively. Also, the correlation between the retention of cerebral 18F-deoxy-thiamine in 60 min after injection as represented by the area under the curve (AUC) and blood thiamine levels was investigated. Results: The 18F-deoxy-thiamine was stable both in vitro and in vivo. The uptake and clearance of 18F-deoxy-thiamine were quick in the mice. It reached the max standard uptake value (SUVmax) of 4.61 ± 0.53 in the liver within 1 min, 18.67 ± 7.04 in the kidney within half a minute. The SUV dropped to 0.72 ± 0.05 and 0.77 ± 0.35 after 60 min of injection in the liver and kidney, respectively. After injection, kidney, liver, and pancreas exhibited high accumulation level of 18F-deoxy-thiamine, while brain, muscle, fat, and gonad showed low accumulation concentration, consistent with previous reports on thiamine distribution in mice. Within 90 min after injection, the level of 18F-deoxy-thiamine in the brain of C57BL/6 mice with thiamine deficiency (TD) was 1.9 times higher than that in control mice, and was 3.1 times higher in ICR mice with TD than that in control mice. The AUC of the tracer in the brain of marmosets within 60 min was 29.33 ± 5.15 and negatively correlated with blood thiamine diphosphate levels (r = − 0.985, p = 0.015). Conclusion: The 18F-deoxy-thiamine meets the requirements for ideal PET tracer for in vivo detecting the status of cerebral thiamine metabolism. [ABSTRACT FROM AUTHOR]

In patients with chronic hepatitis C (CHC), the effects of baseline characteristics, virological profiles, and therapeutic outcome to pegylated interferon plus ribavirin (PR) therapy on autoimmune diseases are unknown. Taiwanese Chronic Hepatitis C Cohort is a nationwide hepatitis C virus registry cohort comprising 23 hospitals of Taiwan. A total of 12,770 CHC patients receiving PR therapy for at least 4 weeks between January 2003 and December 2015 were enrolled and their data were linked to the Taiwan National Health Insurance Research Database for studying the development of 10 autoimmune diseases. The mean follow-up duration was 5.3 ± 2.9 years with a total of 67,930 person-years, and the annual incidence of systemic lupus erythematosus (SLE) or rheumatoid arthritis (RA) was 0.03%. Other autoimmune diseases were not assessable due to few events. Body mass index ≥24 kg/m2 was an independent predictor of the low incidence of SLE or RA (hazard ratio 0.40, 95% confidence interval 0.17–0.93, p = 0.034). A sustained virological response (SVR) to PR therapy was not associated with the low incidence of SLE or RA in any subgroup analysis. CHC patients achieving SVR to PR therapy did not exhibit an impact on the incidence of SLE or RA compared with non-SVR patients. [ABSTRACT FROM AUTHOR]

NAC transcription factors comprise a large plant-specific gene family. Increasing evidence suggests that members of this family have diverse functions in plant growth and development. In this study, we performed a genomewide survey of NAC type genes in maize ( Zea mays L.). A complete set of 148 nonredundant NAC genes ( ZmNAC1-ZmNAC148) were identified in the maize genome using Blast search tools, and divided into 12 groups (a-l) based on phylogeny. Chromosomal location of these genes revealed that they are distributed unevenly across all 10 chromosomes. Segmental and tandem duplication contributed largely to the expansion of the maize NAC gene family. The K/ K ratio suggested that the duplicated genes of maize NAC family mainly experienced purifying selection, with limited functional divergence after duplication events. Microarray analysis indicated most of the maize NAC genes were expressed across different developmental stages. Moreover, 19 maize NAC genes grouped with published stress-responsive genes from other plants were found to contain putative stress-responsive cis-elements in their promoter regions. All these stress-responsive genes belonged to the group d (stress-related). Further, these genes showed differential expression patterns over time in response to drought treatments by quantitative real-time PCR analysis. Our results reveal a comprehensive overview of the maize NAC, and form the foundation for future functional research to uncover their roles in maize growth and development. [ABSTRACT FROM AUTHOR]

To clarify the effect of neoadjuvant chemotherapy (NAC) on the survival outcomes of operable gastric cancers, we searched PubMed, Embase, and Cochrane Library for randomized clinical trials published until June 2014 that compared NAC-containing strategies with NAC-free strategies in patients with adenocarcinoma of the stomach or the esophagogastric junction, who had undergone potentially curative resection. The adjusted pooled hazard ratio (HR) for overall survival (OS) was insignificant when comparing the NAC-containing arm with the NAC-free arm. Subgroup analysis showed that the OS of the treatment arm that involved both adjuvant chemotherapy (AC) and NAC was significantly improved over the control arm (AC only) (HR = 0.48, 95% CI: 0.35-0.67; P < 0.001). While NAC alone plus surgery did not show any survival benefit over surgery alone. Perioperative chemotherapy (PC) also showed a significant increase in PFS and a significant reduction in distant metastasis compared to surgery alone. Therefore, in patients with resectable gastric cancer, NAC alone is not enough and AC alone is not good enough to definitely improve their OS. Collectively, PC combined with surgery could maximize the survival benefit for patients with resectable gastric cancer. [ABSTRACT FROM AUTHOR]

Members of the ankyrin repeats (ANK) gene family encode ANK domain that are common in diverse organisms and play important roles in cell growth and development, such as cell-cell signal transduction and cell cycle regulation. Recently, genome-wide identification and evolutionary analyses of the ANK gene family have been carried out in Arabidopsis and rice. However, little is known regarding the ANK genes in the entire maize genome. In this study, we described the identification and structural characterization of 71 ANK genes in maize ( ZmANK). Then, comprehensive bioinformatics analyses of ZmANK genes family were performed including phylogenetic, domain and motif analysis, chromosomal localization, intron/exon structural patterns, gene duplications and expression profiling. Domain composition analyses showed that ZmANK genes formed ten subfamilies. Five tandem duplications and 14 segmental duplications were identified in ZmANK genes. Furthermore, we took comparative analysis of the total ANK gene family in Arabidopsis, rice and maize, ZmANKs were more closely paired with OsANKs than with AtANKs. At last, expression profile analyses were performed. Forty-one members of ZmANK genes held EST sequences records. Semi-quantitative expression and microarray data analysis of these 41 ZmANK genes demonstrated that ZmANK genes exhibit a various expression pattern, suggesting that functional diversification of ZmANK genes family. The results will present significant insights to explore ANK genes expression and function in future studies in maize. [ABSTRACT FROM AUTHOR]

The quantum theory of the mesoscopic RLC circuit and the condition for Coulomb blockade are given by using canonical quantization and a unitary transformation from the classical equation of motion. Our results show that there is a threshold voltage ℇT in the circuit. The threshold voltage is related not only to the junction capacitance and inductance, but also to the resistance of the circuit. Generally speaking, the larger the resistance, the larger the threshold voltage. This clarifies the phenomenon of the Coulomb blockade of the dissipative mesoscopic circuit. [ABSTRACT FROM AUTHOR]