Sulfur/nitrogen/oxygen tri-doped carbon nanospheres as an anode for potassium ion storage

Carbonaceous materials are considered as ideal anode for potassium ion batteries(PIBs)due to their abundant resources and stable physical and chemical properties.However,improvements of reversible capacity and cycle performance are still needed,aiming to the practical application.Herein,S/N/O tridoped carbon(SNOC)nanospheres are prepared by in-situ vulcanized polybenzoxazine.The S/N/O tridoped carbon matrix provides abundant active sites for potassium ion adsorption and effectively improves potassium storage capacity.Moreover,the SNOC nanospheres possess large carbon interlayer spacing and high specific surface area,which broaden the diffusion pathway of potassium ions and accelerate the electron transfer speed,resulting in excellent rate performance.As an anode for PIBs,SNOC shows attractive rate performance(438.5 mA h g^(-1) at 50 mA g^(-1) and 174.5 mA h g^(-1) at2000 mA g^(-1)),ultra-high reversible capacity(397.4 mA h g^(-1) at 100 mA g^(-1) after 700 cycles)and ultra-long cycling life(218.9 mA h g^(-1) at 2000 mA g^(-1) after 7300 cycles,123.1 mA h g^(-1) at3000 mA g^(-1) after 16500 cycles and full cell runs for 4000 cycles).Density functional theory calculation confirms that S/N/O tri-doping enhances the adsorption and diffusion of potassium ions,and in-situ Fourier-transform infrared explores explored the potassium storage mechanism of SNOC.

非均相复合驱油体系界面性质的影响因素

针对聚驱后油藏特点研发了黏弹性颗粒驱油剂(B-PPG)。文中研究了黏弹性颗粒驱油剂溶液与煤油间的界面张力和扩张流变性质,考察了盐度、二价离子和温度对体系界面张力及扩张流变参数的影响。结果表明,高浓度时,B-PPG通过烷基链的疏水作用形成了二维网络结构,提升了界面膜的强度,临界缔合浓度为1000mg/L。NaCl压缩双电层,增大了B-PPG分子的界面吸附量,界面张力显著降低;同时,由于分子间静电相互作用减弱,扩张弹性急剧降低,而扩散交换的加快导致扩张黏性降低。二价阳离子的加入,造成界面分子排列的紧密程度有所降低,界面张力略有升高。二价阳离子还可以增强B-PPG形成的聚集体结构,导致扩张弹性略有增大。升高温度,加速了B-PPG分子的热运动,扩散交换过程变快,界面膜强度降低。

Facile one-pot synthesis of a BiOBr/Bi_(2)WO_(6) heterojunction with enhanced visible-light photocatalytic activity for tetracycline degradation

Photocatalytic removal of tetracycline(TC)from the wastewater is of great value in the chemical and environmental engineering field.Here,we introduced a facile one-step method for the synthesis of BiOBr/Bi2WO6 heterojunctions by using cheap CTAB as the Br source.We showed the possibility of our method to fine-tune the content of BiOBr in the produced BiOBr/Bi2WO6 by simply changing the dosage of cetyltrimethylammonium bromide(CTAB),providing a platform for the delicate tuning of the visiblelight absorbance ability of the composites.With a suitable heterojunction structure of BiOBr/Bi2WO6-0.2,it exhibited an ultrarapid photocatalytic activity towards TC(20 mg
L^(-1)),with a competitive removal efficiency of 88.1%within 60 min and an ultrahigh removal rate of 0.0349 min^(-1).It could also be robustly recycled for at least 5 cycles with slight removal efficiency loss.We demonstrated that this exciting photocatalytic performance was due to the highly decreased recombination of photoinduced electrons and holes on our composites by constructing this heterojunction structure,and the resulting
OH and
O^(-)_(2)contributed to the effective degradation of TC to CO_(2).

局部晚期及转移性食管鳞癌免疫治疗现状分析

目的:免疫治疗被批准用于晚期食管鳞癌(esophageal squamous cell carcinoma,ESCC)的二线治疗,但临床研究由于其严格的入排标准不能完全反映真实世界的情况。本研究旨在分析局部晚期和转移性ESCC免疫治疗现状,并探索可能影响预后的因素。方法:纳入2018年1月至2020年11月在北京大学肿瘤肿瘤医院接受免疫治疗的局部晚期及转移性ESCC患者,分析临床病理资料、治疗情况、疗效、不良反应和无进展生存期(progression-free survival,PFS)。结果:本研究纳入33例ESCC患者,其中1例合并强制性脊柱炎。患者均接受程序性细胞死亡抑制剂治疗,最常用的药物为信迪利单抗(17/33,52%)。25例(76%)接受免疫联合治疗,包括联合化疗或抗血管靶向治疗。接受一线、二线和三线及以上治疗的ESCC患者分别为19例(58%)、10例(30%)和4例(12%)。1~2级和3~4级治疗相关不良反应发生率分别为64%(21/33)和27%(9/33)。11例(33%)发生免疫相关性不良反应(immune-related adverse events,irAEs),包括:皮疹5例,甲状腺功能减退4例,免疫性肝炎2例,免疫性肠炎2例,反应性毛细血管增生症2例,免疫性肺炎1例。4例irAEs影响免疫治疗使用,其中3例采用类固醇激素治疗。总体客观缓解率为36%(12/33)。中位PFS为9.17个月(95%CI:8.23~10.11)。多因素分析显示基线白细胞计数(P=0.010)、免疫治疗线数(P=0.004)、免疫治疗疗效(P=0.049)是PFS的独立影响因子。结论:免疫治疗在晚期ESCC的临床实践中,药物选择和治疗模式更加多样,但是依然产生良好的疗效。早期应用免疫治疗有效患者可以获得更长的PFS,而白细胞计数升高可能为不良预后因素,未来需扩大人群进一步验证。

Nursing Care of Labor Induction in 2 Cases of Upper GI Bleeding in Pregnancy Complicated with Decompensated Cirrhosis

Objective: To summarize the nursing experience of induced labor of upper gastrointestinal bleeding in pregnancy complicated with decompensated cirrhosis. Methods: To treat two pregnant women with upper gastrointestinal bleeding complicated with decompensated cirrhosis with early labor induction, strengthen the nursing of upper gastrointestinal bleeding before operation, monitor changes of the patient’s condition closely after operation, and strengthen the prevention and treatment of postpartum complications and health guidance. Results: No serious complications occurred in the 2 patients after operation. They were hospitalized for 11 and 17 days after operation and were discharged stably. Conclusion: The pregnant women with upper gastrointestinal bleeding complicated with decompensated cirrhosis should terminate pregnancy in time and strengthen perinatal nursing, which can improve the liver function and blood coagulation and improve the prognosis of the patients.

The Effect of MRP5-Expression on Human Erythroleukemia (HEL) Cell Growth and cGMP Levels

Background: Previous studies of patients with acute leukemia showed that plasma cGMP levels were markedly elevated before treatment, fell after successful therapy but increased after relapse. In many cells high concentrations of GMP have an antiproliferative effect. The cellular cGMP extrusion from cancer cells may represent an acquired resistance against an endogenous antiproliferative signal molecule. Multidrug resistance associated protein 5 (MRP5) has been identified as an important cGMP transporter. Methods: A human erythroleukemia cell line (HEL) was used to study the impact of cGMP and cGMP-elevating compounds like theophylline, sodium nitroprusside (SNP) and sodium nitrite (NaNO2). MRP5 was overexpressed in HEL cells by transfection. Concentrations of cGMP were determined with RIA or HPLC and cell densities were determined by cytometry. Results: The concentration ratio between extra- and intracellular cGMP concentrations was >1, meaning that HEL cells extruded cGMP against a concentration gradient and MRP5 was identified in these cells. In some cell types butyrate increases cellular cGMP levels by stimulating soluble guanylyl cyclase (sGC) and thereby the cellular efflux. This effect did not exist for HEL cells. MRP5 transfected HEL cells which were exposed to cGMP was clearly more sensitive to the antiproliferative effect than the wild type. On the other hand, exposing the transfected HEL cells to cGMP-elevating agents (theophylline, SNP and NaNO2) showed less sensitivity than the wildtype. Conclusion: This study supports the idea that some cancers acquire resistance against endogenous signal molecules with antiproliferative potency.

单中心奥沙利铂超敏反应的处理及转归真实世界研究

目的:通过对输注奥沙利铂导致的超敏反应的临床特点、处理方式和临床转归进行分析,为临床诊治提供依据。方法:回顾性分析2015年1月至2017年12月北京大学肿瘤医院上报国家药品不良反应监测中心的62例奥沙利铂超敏反应患者的临床资料,按国际通用标准分型为标准输液反应与严重过敏反应,分析其临床特征、超敏反应亚型、严重程度分级、处理方式及转归。结果:患者平均年龄(52.9±11.3)岁,男女比例1.07:1。59.7%(37/62)患者在输注奥沙利铂前使用了糖皮质激素预处理。发生超敏反应时奥沙利铂中位治疗为6(4~7.25)个周期,中位累积剂量456.9(263.5~651.0)mg/m^2。30.6%(19/62)患者存在无奥沙利铂间隔期。41例(66.1%)患者诊断为标准输液反应,21例(33.9%)诊断为严重过敏反应。在处理方式上,所有患者均采取了暂停用药、更换输液器的处理,无患者使用肾上腺素;所有患者症状均缓解,无死亡病例。58.6%(17/29)需要继续进行治疗的2级标准输液反应患者进行了再次用药,其中70.6%(12/17)未再次出现超敏反应。结论:临床对奥沙利铂输注前预处理不足,严重过敏反应的肾上腺素的一线使用尚未得到足够重视,大部分轻中度奥沙利铂超敏反应后续可再次安全用药。

直肠癌病理标本大体肿瘤周边微小癌灶距离的测定

目的:根据直肠癌病理标本分别测量大体肿瘤侧方、下方和上方微小癌灶距离(即临床靶体积,clinical target volume,CTV),为其放疗临床靶区体积边径设置提供科学依据。方法:分析2016年10月至2017年4月在湖南省肿瘤医院行全直肠系膜切除术(total mesorectal excision,TME)的直肠癌标本28例,测量其周边最远微小癌灶距大体肿瘤边缘最近距离值。通过MRI和即时手术标本对比计算“在体-离体”肿瘤退缩因子(R1);“线结标记法”计算病理标本处理过程退缩因子(R2)。对实测微小癌灶延伸距离采用两种退缩因子(R1、R2)校正后即为“在体”微小癌灶延伸距离(microcarcinoma extension measured in vivo,MEin vivo)。结果:28例患者中,在大体肿瘤侧方、下方和上方可观察到微小癌灶者分别为17例(60.7%)、3例(10.7%)和0。R1平均值为0.913,R2平均值为0.803。实测微小癌灶在直肠癌大体肿瘤下方最远距离经校正后为28 mm,在大体肿瘤侧方最远距离经校正后最大值为12.03 mm,最小值为3.13 mm,平均值为7.50 mm。28例患者侧方微小癌灶侵袭范围95%频数值在10 mm内。结论:直肠癌大体肿瘤侧方微小癌灶侵袭范围95%频数值在10 mm内,建议直肠癌后程高剂量放疗靶区在前后左右方向大体肿瘤体积(gross tumorvolume,GTV)外扩成CTV时边径为10 mm。

High sulfur-doped hard carbon anode from polystyrene with enhanced capacity and stability for potassium-ion storage

Carbonaceous materials are regarded as a promising anode material for potassium ion batteries(PIBs)due to their high electronic conductivity, abundant resources and low cost. However, relatively low storage capacity and structural instability still hinder their practical application. Herein, high sulfur-doped hard carbon(SHC-3) with a sulfur up to 27.05 at% is synthesized from polystyrene and sulfur as precursors. As an anode for PIBs, the SHC-3 delivers a superb cycling stability and rate performance(298.1 mAh g^(-1)at 100 mA g^(-1) for 1000 cycles, a capacity retention of 95.2%;220.2 mAh g^(-1)at 500 mA g^(-1) after 5200 cycles). The potassium storage of SHC-3 exhibits excellent cyclic stability at both low and high rates.Structure and kinetic studies demonstrate that the larger interlayer spacing(0.382 nm) of the SHC-3 accelerates the diffusion of potassium ions and effectively alleviates the volume expansion, and thus maintains the structure stability during the process of potassization/de-potassization. Meanwhile, the density functional theory calculation shows that the doped sulfur atoms provide abundant active sites for the adsorption of potassium ions, thereby increasing the reversible capacity of PIBs. This work provides a new scheme for the design of carbonaceous anode materials with high capacity and long cycle life.

Environmental Analysis with 2D Transition-Metal Dichalcogenide-Based Field-Effect Transistors

Field-effect transistors(FETs)present highly sensitive,rapid,and in situ detection capability in chemical and biological analysis.Recently,two-dimensional(2D)transition-metal dichalcogenides(TMDCs)attract significant attention as FET channel due to their unique structures and outstanding properties.With the booming of studies on TMDC FETs,we aim to give a timely review on TMDCbased FET sensors for environmental analysis in different media.First,theoretical basics on TMDC and FET sensor are introduced.Then,recent advances of TMDC FET sensor for pollutant detection in gaseous and aqueous media are,respectively,discussed.At last,future perspectives and challenges in practical application and commercialization are given for TMDC FET sensors.This article provides an overview on TMDC sensors for a wide variety of analytes with an emphasize on the increasing demand of advanced sensing technologies in environmental analysis.

Reduced graphene oxide doping flower-like Fe_(7)S_(8) nanosheets for high performance potassium ion storage

Finding easy-to-operate strategy to obtain anode material with well-designed structure and excellent electrochemical performance is necessary to promote the development of the future potassium-ion batteries(PIBs).In this work,we synthesized reduced graphene oxide doping flower-like Fe_(7)S_(8) nanosheets electrode materials using one-step hydrothermal strategy.The rGO@Fe_(7)S_(8) composite is composed of homogeneous Fe_(7)S_(8) and reduced graphene oxide thin nanosheets.This unique structure not only promotes the penetration of electrolyte and increases the conductive of the pure Fe_(7)S_(8) electrode materials,but also relieves the volume expansion of K^(+) during charge/discharge process.When applied this interesting anode electrode for PIBs,the rGO@Fe_(7)S_(8) exhibits excellent electrochemical performance.It delivers a high reversible specific capacity of 445 mAh g^(-1) at 50 mA g^(-1),excellent rate performance(284 mAhg^(-1)at 500 mA g^(-1) and 237 mAh g^(-1) at 1000 mA g^(-1)),and a high cycling stability at 100 mA g^(-1)(maintained 355 mAh g^(-1) after 300 cycles).

Digital biomedical electrical impedance tomography based on FPGA

A digital biomedical electrical impedance tomography (EIT) system is developed with the aid of FPGA. The key elements of EIT system are described specifically in the paper. The functions are realized to generate excitation source, switch electrode channels, deal collected signals, demodulate measured voltages etc. The system is tested by a circular tank with 16 stainless electrodes attached around the boundary. The adjacent incentive adjacent measurement mode is adapted to collect boundary voltages of the interesting field. By testing, the system works with 36 dB signal-to-noise ratio (SNR) when 1 mA 100 KHz current is applied into a homogenous tank.

Disrupted tenogenesis in masseter as a potential cause of micrognathia

Micrognathia is a severe craniofacial deformity affecting appearance and survival. Previous studies revealed that multiple factors involved in the osteogenesis of mandibular bone have contributed to micrognathia, but concerned little on factors other than osteogenesis. In the current study, we found that ectopic activation of Fgf8 by Osr2-cre in the presumptive mesenchyme for masseter tendon in mice led to micrognathia, masseter regression, and the disrupted patterning and differentiation of masseter tendon. Since Myf5-cre;Rosa26R-Fgf8 mice exhibited the normal masseter and mandibular bone, the possibility that the micrognathia and masseter regression resulted directly from the over-expressed Fgf8 was excluded. Further investigation disclosed that a series of chondrogenic markers were ectopically activated in the developing Osr2-cre;Rosa26R-Fgf8 masseter tendon, while the mechanical sensing in the masseter and mandibular bone was obviously reduced. Thus, it suggested that the micrognathia in Osr2-cre;Rosa26R-Fgf8 mice resulted secondarily from the reduced mechanical force transmitted to mandibular bone. Consistently,when tenogenic or myogenic components were deleted from the developing mandibles, both the micrognathia and masseter degeneration took place with the decreased mechanical sensing in mandibular bone, which verified that the loss of mechanical force transmitted by masseter tendon could result in micrognathia. Furthermore, it appeared that the micrognathia resulting from the disrupted tenogenesis was attributed to the impaired osteogenic specification, instead of the differentiation in the periosteal progenitors. Our findings disclose a novel mechanism for mandibular morphogenesis, and shed light on the prevention and treatment for micrognathia.

The prognostic potential of pretreatment C-reactive protein to albumin ratio in stage IE/IIE extranodal natural killer/T-cell lymphoma

Objective The aim of this study was to determine the prognostic significance of the C-reactive protein-toalbumin ratio (CRP/Alb) for stage IE/IIE upper aerodigestive tract extranodal NK/T cell lymphoma patients. Methods One hundred and fourteen patients diagnosed with extranodal NK/T cell lymphoma at Sichuan Cancer Hospital from September 2011 to November 2016 were retrospectively reviewed. An optimal cutoff value of CRP/Alb for overall survival rate as an endpoint was obtained using the receiver operating curve (ROC). Results The optimal cutoff value of CRP/Alb was 0.15. For the low CRP/Alb group, the 3-year progression-free survival (PFS) was 78.6% and the 3-year overall survival (OS) was 80.7%. The 3-year PFS and OS values for the high CRP/Alb group were 41.6% and 45.2%, respectively. Differences for PFS (P < 0.001) and OS (P < 0.001) between the two groups were statistically significant. Univariate analysis showed that ECOG, IPI, CRP, GPS, and CRP/Alb were significantly associated with PFS. Similarly, all five were also significantly associated with OS. Multivariate analysis further confirmed that ECOG and CRP/ Alb were independent prognostic factors for both PFS and OS. Moreover, the cutoff value of CRP/Alb showed superior prognostic ability in discriminating between patients with different outcomes in low-risk group based on GPS, IPI, and KPI scores. Conclusion CRP/Alb is a promising prognostic marker for early-stage extranodal NK/T cell lymphoma.

Strong Law of Large Numbers under an Upper Probability

Strong law of large numbers is a fundamental theory in probability and statistics. When the measure tool is nonadditive, this law is very different from additive case. In 2010 Chen investigated the strong law of large numbers under upper probabilityVby assumingVis continuous. This assumption is very strong. Upper probabilities may not be continuous. In this paper we prove the strong law of large numbers for an upper probability without the continuity assumption whereby random variables are quasi-continuous and the upper probability is generated by a weakly compact family of probabilities on a complete and separable metric sample space.

Edge Detection Based on Generative Adversarial Networks

Aiming at the problem that the detection effect of traditional edge detection algorithm is not good,and the problem that the existing edge detection algorithm based on convolution network cannot solve the thick edge problem from the model itself,this paper proposes a new edge detection method based on the generative adversarial network.The confrontation network consists of generator network and discriminator network,generator network is composed of U-net network and discriminator network is composed of five-layer convolution network.In this paper,we use BSDS500 training data set to train the model.Finally,several images are randomly selected from BSDS500 test set to compare with the results of traditional edge detection algorithm and HED algorithm.The results of BSDS500 benchmark test show that the ODS and OIS indices of the proposed method are 0.779 and 0.782 respectively,which are much higher than those of traditional edge detection algorithms,and the indices of HED algorithm using non-maximum suppression are similar.

Grammar Instruction and Evaluation of an EFL Textbook of China

By examining recent studies on grammar instruction, which reflect the waxing and waning of grammar instruction in history, and some new teaching approaches and techniques in grammar teaching, this paper concludes that grammar instruction does make a difference to foreign language teaching and thus is important and necessary for Chinese leamers, especially English majors, to develop their ability of using the language accurately and fluently in real life. And on the basis of it, this paper evaluates an EFL textbook of China in terms of some grammar teaching approaches and techniques to illustrate the application and practice of these new perspectives and new teaching approaches and techniques in Chinese foreign language teaching and leaming.

同轴静电喷涂法制备核壳靶向示踪重组人白细胞介素Ⅱ微球

重组人白细胞介素-2(rh IL-2)具有促进免疫细胞增殖和分化的潜能,可用于治疗肺癌。然而,rh IL-2半衰期短,生物活性不稳定,需要将其载入微球中进行缓释给药。本研究采用同轴静电喷涂技术制备了载rh IL-2的核壳微球。以量子点为示踪材料,核层用壳聚糖做载体包裹rh IL-2和量子点偶联物,壳层采用透明质酸做载体制备核壳复合微球。采用单因素法对载体浓度、电压、针孔内径、喷雾流量等因素进行了研究。优化了同轴静电喷雾法制备核壳微球的工艺参数。结果表明,制备的核壳微球粒径在1.2–2.0μm,包封率和载药量分别为78.39%±1.96%和19.58±2.76μg/mg。体外释放实验显示微球释放效果较好,无突释现象。该制剂的生物学活性实验表明,核壳微球中的rh IL-2与游离蛋白药物具有相同的作用。体内成像分析也显示微球具有主动靶向性。本研究为rh IL-2靶向缓释微球的研制提供了理论依据。

A Homozygotic Mutation in KDSR may Cause Keratinization Disorders and Thrombocytopenia: A Case Report

Pathogenic mutations in 3-keto-dihydrosphingosine reductase(KDSR)gene are associated with keratinization disorders and impaired platelet function.However,no case with both homozygotic mutation of KDSR and hepatic hemangioendothelioma has ever been reported due to its low prevalence.Here we report a seven months old Chinese boy with a homozygotic missense mutation in KDSR and both of his parents carry a same heterozygous mutation.He was born with thick plate-like scales overlying erythrodermic skin,but the skin symptoms were resolved spontaneously over the first month of his birth.He was also diagnosed with hepatic hemangioendothelioma at birth and accepted a resection surgery at 2 months old.At birth,his platelet count was severely low(10-20×10~9/L)with recurrent skin and gingival bleeding.Meanwhile,he suffered a mild normocytic,normochromic anemia with normal iron and hematinic levels.The anemia spontaneously recovered over the first 6 months,while the platelet count keeped at a low level(4-20×10~9/L).Treatment with corticosteroids,immunoglobulin or thrombopoietin was all suboptimal.

Study on Soil Infiltration Capability and Its Impact Factors of Different Land-use Types in Purple Soil Region

Soil infiltration capability is the hot spot topic of soil erosion studies and soil physical and chemical properties have great influence on it. A new infiltration method point- source infiltration method was used to precisely evaluate the infiltration capability in different purple soil land- use types. And correlation analysis on soil physical and chemical properties and soil infiltration capability of different land- use types was performed. Results showed that:( i) there is a large difference among soil physical and chemical properties in different land- use types,soil water content,non- capillary porosity,capillary porosity,content of > 0. 25 mm aggregates and organic matter content in the top soil are greater than those in the subsoil;( ii) soil infiltration capability showed differences among different land- use types. Land use showed great effects,in general,the order of decrease on initial infiltration rate and average infiltration rate was: woodland slope > slope farmland >grassland,the order of decrease on steady infiltration rate was: slope farmland > woodland > grassland and the time reaching stable state was:slope farmland > woodland > grassland;( iii) correlation analysis showed that there was a significantly positive correlation between initial infiltration rate and wet sieve MWD value and structural damage rate,and it had a significantly negative correlation with capillary porosity;( iv)steady infiltration rate and non- capillary porosity showed the significantly positive correlation,and it had a significantly negative correlation with the soil bulk density;( v) the average infiltration rate and non- capillary porosity and structural damage rate showed a positive correlation and the correlation coefficient was large and there was a negative correlation between average infiltration rate and soil bulk density and capillary porosity,and the absolute value of correlation coefficient was relatively large. The results of this study can provide the theoretical basis for soil infiltration study in purple soil area.