A Novel Fracturing Fluid with High-Temperature Resistance for Ultra-Deep Reservoirs

Ultra-deep reservoirs play an important role at present in fossil energy exploitation.Due to the related high temperature,high pressure,and high formation fracture pressure,however,methods for oil well stimulation do not produce satisfactory results when conventional fracturing fluids with a low pumping rate are used.In response to the above problem,a fracturing fluid with a density of 1.2~1.4 g/cm^(3)was developed by using Potassium formatted,hydroxypropyl guanidine gum and zirconium crosslinking agents.The fracturing fluid was tested and its ability to maintain a viscosity of 100 mPa.s over more than 60 min was verified under a shear rate of 1701/s and at a temperature of 175℃.This fluid has good sand-carrying performances,a low viscosity after breaking the rubber,and the residue content is less than 200 mg/L.Compared with ordinary reconstruction fluid,it can increase the density by 30%~40%and reduce the wellhead pressure of 8000 m level reconstruction wells.Moreover,the new fracturing fluid can significantly mitigate safety risks.

内镜下治疗246例大肠有蒂大息肉的临床分析

目的探讨如何选择大肠有蒂大息肉圈套电切除方式。方法回顾性分析2016年1月-2020年1月246例(259枚息肉)在厦门市中医院行大肠有蒂大息肉(直径≥1.0 cm)圈套电切除治疗患者的内镜和病理资料,统计内镜下黏膜切除术(EMR)组、钛夹组和尼龙绳组内镜下治疗操作成功率、息肉整块切除率、完整切除率、治愈性切除率和并发症发生率。结果有蒂大息肉中,腺瘤性息肉形态改变86.89%(179/206)高于非腺瘤性息肉的28.30%(15/53)(P <0.01)。尼龙绳组息肉直径最大(2.13±0.70) cm,钛夹组(1.51±0.44) cm,EMR组最小(1.31±0.31) cm,3组比较,差异有统计学意义(P <0.05)。尼龙绳组癌变率为46.15%(24/52),高于EMR组的17.24%(25/145)(P <0.01)。圈套电切除息肉完整切除率、整块切除率均为100.00%,治愈性切除率为98.46%(255/259),出血率为7.34%(19/259),穿孔率为0.00%(0/259)。EMR组操作成功率和治愈性切除率均为100.00%(145/145),钛夹组分别为98.39%(61/62)和100.00%(62/62),尼龙绳组均为92.31%(48/52)。EMR组出血率、术中出血率和术后出血率分别为10.34%(15/145)、8.97%(13/145)和2.07%(3/145),钛夹组分别为1.61%(1/62)、0.00%(0/62)和1.61%(1/62),尼龙绳组分别为5.77%(3/52)、3.85%(2/52)和1.92%(1/52),钛夹/尼龙绳预防性蒂部结扎分别为3.51%(4/114)、1.75%(2/114)和1.75%(2/114)。结论≥1.0 cm的有蒂息肉直径越大、癌变率越高。临床上可根据息肉直径不同采用EMR法、钛夹或尼龙绳法,钛夹/尼龙绳预防性蒂部结扎对预防出血有一定的作用。

A Methodology for Reliability of WSN Based on Software Defined Network in Adaptive Industrial Environment

As communication technology and smart manufacturing have developed, the industrial internet of things(IIo T)has gained considerable attention from academia and industry.Wireless sensor networks(WSNs) have many advantages with broad applications in many areas including environmental monitoring, which makes it a very important part of IIo T. However,energy depletion and hardware malfunctions can lead to node failures in WSNs. The industrial environment can also impact the wireless channel transmission, leading to network reliability problems, even with tightly coupled control and data planes in traditional networks, which obviously also enhances network management cost and complexity. In this paper, we introduce a new software defined network(SDN), and modify this network to propose a framework called the improved software defined wireless sensor network(improved SD-WSN). This proposed framework can address the following issues. 1) For a large scale heterogeneous network, it solves the problem of network management and smooth merging of a WSN into IIo T. 2) The network coverage problem is solved which improves the network reliability. 3) The framework addresses node failure due to various problems, particularly related to energy consumption.Therefore, it is necessary to improve the reliability of wireless sensor networks, by developing certain schemes to reduce energy consumption and the delay time of network nodes under IIo T conditions. Experiments have shown that the improved approach significantly reduces the energy consumption of nodes and the delay time, thus improving the reliability of WSN.

Replication of hepatitis B virus in primary duck hepatocytes transfected with linear viral DNA

AIM: To explore the expression and replication of hepatitis B virus (HBV) DNA in primary duck hepatocytes (PDHs).METHODS: Complete HBV genome was transfected into PDHs by electroporation (transfected group, 1.19×1012copies of linear HBV DNA/1×107 PDHs). After 1-5 d of transfection, HBsAg and HBeAg in the supernatant and lysate of PDHs were measured with the IMX System.Meanwhile, replicative intermediates of HBV DNA were analyzed by Southern blotting and Dot blotting. PDHs electroporated were used as control group.RESULTS: HBsAg in the hepatocyte lysates of transfected group was 15.24 (1 d), 14.55 (3 d) and 5.13 (5 d; P/N values, positive≥2.1) respectively. HBeAg was negative (＜2.1). Both HBsAg and HBeAg were negative in the supernatant of transfected group. Dot blotting revealed that HBV DNA was strongly positive in the transfected group and negative in the control group. Southern blot analysis of intracellular total DNA indicated that there were relaxed circular (rc DNA), covalently closed circular (ccc DNA), and single-stranded (ss DNA) HBV DNA replicative intermediates in the transfected group, there was no integrated HBV DNA in the cellular genome. These parameters were negative in control group.CONCLUSION: Expression and replication of HBV genes can occur in hepatocytes from non-mammalian species.HBV replication has no critical species-specificity, and yet hepatic-specific regulating factors in hepatocytes may be essential for viral replication.

Metabolomics and biomarkers in ocular matrix: beyond ocular diseases

According to the recent report,there are 870 million people suffer from ocular diseases worldwide.The present approaches for diagnosis are morphological examination,imaging examination and immunological examination,regrettably,they lack of sensitivity and difficult to make a definite diagnosis in the early stage.Systemic biology as an effective method has been used in clinical diagnosis and treatment for diseases,especially metabolomics which is more attractive with high sensitivity and accuracy.Although previous researches had been confirmed that endogenous metabolites in the ocular matrix play a crucial role in the progress of diseases related diseases,the standard protocols and systematic summary about the biomarker researches based on ocular matrix has not been established.This review article highlights the pretreatment for ocular matrix and the new biomarkers expressed by the eye diseases,expected to promote the application of biomarkers in the diagnosis and treatment of eye diseases.

Social bots and mass media manipulated public opinion through dual opinion climate

Opinion dynamics models based on the multi-agent method commonly assume that interactions between individuals in a social network result in changes in their opinions.However,formation of public opinion in a social network is a macroscopic statistical result of opinions of all expressive individuals(corresponding to silent individuals).Therefore,public opinion can be manipulated not only by changing individuals'opinions,but also by changing their states of expression(or silence)which can be interpreted as the phenomenon"spiral of silence"in social psychology.Based on this theory,we establish a"dual opinion climate"model,involving social bots and mass media through a multi-agent method,to describe mechanism for manipulation of public opinion in social networks.We find that both social bots(as local variables)and mass media(as a global variable)can interfere with the formation of public opinion,cause a significant superposition effect when they act in the same direction,and inhibit each other when they act in opposite directions.

Effects of bone morphogenetic protein-4 on spatial memory and cholinergic expression in the dentate gyrus after fornix-fimbria transection in rats

BACKGROUND： Previous experiments have confirmed bone morphogenetic proteins （BMPs） upregulate cholinergic expression in neurons isolated from the embryonic rat hippocampus and cerebral cortex. Therefore, BMPs could be useful for treating Alzheimer＇s disease and other neurodegenerative diseases. OBJECTIVE： BMP-4 was infused into the hippocampal dentate gyrus of fomix-fimbria transected rats to test the effects of BMP-4 on cholinergic expression in dentate gyrus neurons, and to observe changes in spatial memory behavior. DESIGN： A randomized controlled animal experiment. SETTING： Department of Neurosurgery and Laboratory for Cell Biology, Institute of Geriatrics, General Hospital of Chinese PLA. MATERIALS： Twenty-seven healthy adult male Sprague Dawley （SD） rats, weighing 250-300 g, were provided by the Laboratory Animal Center of the General Hospital of Chinese PLA. Reagents： BMP-4 （B-2680, Sigma Company） and choline acetyl transferase （CHAT） antibody （AB5042, Chemicon Company） were used in this study. Equipments： a rat stereotaxic instrument （type： SN-2N, Narushige Group, Japan） and Image-prog-plus image analysis software （Media Cybernetics company, USA） were used in this study. The protocol was carried out in accordance with ethical guidelines for the use and care of animals. METHODS： This experiment was performed in the Institute of Geriatrics, General Hospital of Chinese PLA between July 2004 and March 2005. Rats were randomly divided into 4 groups： Alzheimer＇s disease group （n = 7）, normal control group （n = 5）, BMP-4-Alzheimer＇s disease group （n = 8）, and model group （n = 7）. In the Alzheimer＇s disease group, the left hippocampal fomix-fimbria of rats was transected to mimic Alzheimer＇s disease symptoms. In the BMP-4-Alzheimer＇s disease group, 1 μt L BMP-4 （10 mg/L） was perfused into the left dentate gyrus with a microinjector at 1 μ L/min. In the model group, 1 μ L saline was perfused into the same position by the same method. Twenty-eight days after injection, Morris water maze test was performed in all rats to test spatial memory. Time-to-platform and swim-path length were recorded. Immunohistochemical staining of cholinergic neurons was performed on brain sections containing dentate gyrus. The area covered by ChAT-positive cells was analyzed using an Image-prog-plus image analysis software. MAIN OUTCOME MEASURES： Area covered by ChAT-positive cells in the dentate gyrus. Time-to-platform and swim path-length. RESULTS： Twenty-seven rats were included in the final analysis. In the Alzheimer＇s disease group, the area covered by ChAT-positive cells was significantly smaller compared with the normal control group （F = 76.03, P 〈 0.01）. The area covered by ChAT-positive cells was significantly larger in the BMP-4- Alzheimer＇s disease group than in the model group （F = 35.17, P 〈 0.05）, but significantly smaller than in the normal control group （F = 40.17, P 〈 0.05）. Time-to-platform and swim-path length were significantly longer in the Alzheimer＇s disease group than in the normal control group （F =24.62 and 631.58, respectively, both P 〈 0.05）. Time-to-platform and swim-path length were significantly shorter in the BMP4-Alzheimer＇s disease group compared with the model group （F= 22.06 and 606.89, respectively P 〈 0.05）. CONCLUSION： Injection of BMP-4 into the dentate gyrus of Alzheimer＇s disease model rats alleviates central cholinergic system injury and concomitantly improves spatial memory.

Ecological study of cave nectar bats reveals low risk of direct transmission of bat viruses to humans

Bats are reservoirs of various viruses.The widely distributed cave nectar bat(Eonycteris spelaea)is known to carry both filoviruses and coronaviruses.However,the potential transmission of theses bat viruses to humans is not fully understood.In this study,we tracked 16 E.spelaea bats in Mengla County,Yunnan Province,China,using miniaturized GPS devices to investigate their movements and potential contact with humans.Furthermore,to determine the prevalence of coronavirus and filovirus infections,we screened for the nucleic acids of the Měnglàvirus(MLAV)and two coronaviruses(GCCDC1-CoV and HKU9-CoV)in anal swab samples taken from bats and for antibodies against these viruses in human serum samples.None of the serum samples were found to contain antibodies against the bat viruses.The GPS tracking results showed that the bats did not fly during the daytime and rarely flew to residential areas.The foraging range of individual bats also varied,with a mean cumulative nightly flight distance of 25.50 km and flight speed of up to 57.4 km/h.Taken together,these results suggest that the risk of direct transmission of GCCDC1-CoV,HKU9-CoV,and MLAV from E.spelaea bats to humans is very low under natural conditions.

Fe-doped ZnS film fabricated by electron beam evaporation and its application as saturable absorber for Er:ZBLAN fiber laser

High-quality Fe-doped Zn S films have been fabricated by electron beam evaporation.After the doping,the fabricated films still maintain the preferential crystalline orientation and phase purity of the host Zn S.According to the observation of surface morphology,the root mean-square roughness of the samples increases slightly with the increase of doping content.All of the prepared samples are in cubic zinc blende structure of Zn S.Transmission spectrum confirms a more obvious dip near 3μm with higher dopant concentration and it can be attributed to the typical^(5)E→^(5)T_(2)transition of Fe^(2+).Fe-doped Zn S film is also successfully used for Q-switched Er:ZBLAN fiber laser.

Laparoscopic treatment of bilateral duplex kidney and ectopic ureter: A case report

BACKGROUND Duplication of the renal pelvis is a common congenital malformation of the urinary system.About one-third of cases are complete unilateral duplication of the renal pelvis,while bilateral duplication is extremely rare.Herein,we described a single case of bilateral renal duplication with double ureteral orifice ectopic vaginal fistula treated with laparoscopy.CASE SUMMARY A 6-year-old girl suffering from long-term vaginal leakage was admitted on June 10,2018.She was diagnosed with complete duplication of both kidneys and ureters and ectopic opening of both ureters combined with ureterovaginal fistula.The patient received laparoscopic ectopic ureteral bladder replantation and was followed up for 2 years.No renal function damage and vaginal leakage were found.CONCLUSION Laparoscopic bladder-ureter reimplantation could effectively determine the location and number of ectopic ureters by imaging and cystoscopy.

Exploring the anti-diabetic effects and the underlying mechanisms of ethyl acetate extract from Sophora flavescens by integrating network pharmacology and pharmacological evaluation

Background:Sophora flavescens,a traditional Chinese herb medicine,has been used to prevent and cure type 2 diabetes mellitus(T2DM)both in folk medicine and medical institutions.Modern pharmacological studies have also demonstrated that the flavonoids obtained from Sophora flavescens ethyl acetate extract(SFE)exhibited potential anti-diabetic activity.Our previous study elucidated that SFE exerts anti-T2DM effects by regulating the host-microbial metabolic axis.In the present study,we further explored the pharmacodynamic effect and the potential targets of the anti-T2DM activity of SFE by integrating network pharmacology and pharmacological evaluations.Methods:The diabetic rat model was created by streptozotocin and oral administration with SFE for 8 weeks.Then,the T2DM-related index was estimated to assess the interventional effect of SFE.Network pharmacology was applied to identify the likely targets and the pathways modulated by SFE components.Furthermore,Western blotting was applied to verify the prediction.Results:Pharmacological evaluation in vivo revealed that SFE could markedly improve the blood glucose,serum insulin secretion,insulin resistance,liver glycogen synthesis,and the liver tissue structure in T2DM rats.Through network pharmacology analysis,101 active compounds of SFE and 114 targets belonging to 128 pathways were identified.The insulin,TNF,IL-6,and PI3K/Akt pathway may be the key targets and pathway.Based on the results of network pharmacology analysis,IRS/PI3K/Akt and IKK/NF-κB/TNF pathways were selected for further validation.Subsequently,experimental results of Western blotting confirmed that SFE may exert anti-T2DM effects by modulating the IRS/PI3K/Akt and IKK/NF-κB/TNF pathways.Conclusion:SFE may protect the T2DM rats by relieving the insulin resistance and inflammation through regulating the IRS/PI3K/Akt and IKK/NF-κB/TNF pathways.The results of the present study would improve the comprehension of the pharmacological basis of SFE against T2DM and provide a theoretical basis for the clinical use of Sophora flavescens.

Early Identification and Diagnosis of Adrenal Crisis after Retroperitoneal Laparoscopic Unilateral Adrenalectomy

The occurrence of adrenal crisis after retroperitoneal laparoscopic unilateral adrenalectomy is usually concealed.If not timely diagnosis and treatment,it may cause shock,and even lead to death.It is very difficult to distinguish the clinical manifestations of adrenal crisis from nausea,vomiting,fatigue,gas separation from the lower diaphragm,abdominal pain,hypotension,hypertension,fever and hypothermia after operation.This makes it very difficult to identify and diagnose adrenal crisis early.This article mainly discusses the early recognition,diagnosis and treatment of adrenal crisis after unilateral adrenalectomy by retroperitoneoscope.

Corrosion Behavior of Cu₆₀Zr₃₀Ti₁₀Metallic Glass in the Cl^–Containing Solution

Cu60Zr30Ti10 (at. %) ribbon was prepared by melt spinning. Its glassy structure was confirmed by X-ray diffraction (XRD). Its corrosion behavior in HCl and NaCl solutions was investigated by electrochemical polarization measurement. The surfaces before and after corrosion were observed with scanning electron microscope (SEM) and analysis was performed using electron dispersive spectroscopy (EDS). The results show that the decrease of current density is due to the formation of a mixture of simple oxides or complex oxidic compounds. In both cases, the corrosion potential decreases with increasing chloride concentration. The passive film forms easier in HCl than in NaCl. In addition, the higher is the chloride concentration, the easier is the passivation.

Inverse Measurement of Moisture Content in Porous Insulation Materials with a Data Sorting Method

Moisture in insulation materials will impair their thermal and acoustic performance, induce microbe growth, and cause equipment/material corrosion. Moisture content measurement is vital to the effective moisture control. This investigation proposes a simple, fast, and accurate method to measure moisture content of insulation materials through matching the measured temperature rise. Since moisture content corresponds to unique thermophysical properties, the measured temperature rise varies with moisture content. During the data analysis, all possible volumetric heat capacities and thermal conductivities are enumerated to match the measured temperature rise based on the composite heat conduction theory. Then, the partial derivatives with respect to both volumetric heat capacity and thermal conductivity are evaluated, so that these partial derivatives will be guaranteed equaling to zero at the optimal solutions to the moisture content. Compared to the benchmarked gravimetric method, this proposed method was found having a better accuracy but requiring a short test time.

Efficient and stable hybrid perovskite-organic light-emitting diodes with external quantum efficiency exceeding 40 per cent

Light-emitting diodes(LEDs)based on perovskite semiconductor materials with tunable emission wavelength in visible light range as well as narrow linewidth are potential competitors among current light-emitting display technologies,but still suffer from severe instability driven by electric field.Here,we develop a stable,efficient and highcolor purity hybrid LED with a tandem structure by combining the perovskite LED and the commercial organic LED technologies to accelerate the practical application of perovskites.Perovskite LED and organic LED with close photoluminescence peak are selected to maximize photon emission without photon reabsorption and to achieve the narrowed emission spectra.By designing an efficient interconnecting layer with p-type interface doping that provides good opto-electric coupling and reduces Joule heating,the resulting green emitting hybrid LED shows a narrow linewidth of around 30 nm,a peak luminance of over 176,000 cd m^(−2),a maximum external quantum efficiency of over 40%,and an operational half-lifetime of over 42,000 h.

Longitudinal Surveillance of Betacoronaviruses in Fruit Bats in Yunnan Province,China During 2009–2016

Previous studies indicated that fruit bats carry two betacoronaviruses,BatCoV HKU9 and BatCoV GCCDC1.To investigate the epidemiology and genetic diversity of these coronaviruses,we conducted a longitudinal surveillance in fruit bats in Yunnan province,China during 2009–2016.A total of 59(10.63%)bat samples were positive for the two betacorona-viruses,46(8.29%)for HKU9 and 13(2.34%)for GCCDC1,or closely related viruses.We identified a novel HKU9 strain,tentatively designated as BatCoV HKU9-2202,by sequencing the full-length genome.The BatCoV HKU9-2202 shared 83%nucleotide identity with other BatCoV HKU9 stains based on whole genome sequences.The most divergent region is in the spike protein,which only shares 68%amino acid identity with BatCoV HKU9.Quantitative PCR revealed that the intestine was the primary infection organ of BatCoV HKU9 and GCCDC1,but some HKU9 was also detected in the heart,kidney,and lung tissues of bats.This study highlights the importance of virus surveillance in natural reservoirs and emphasizes the need for preparedness against the potential spill-over of these viruses to local residents living near bat caves.

孤立肾合并肾混合性上皮间质肿瘤一例报告并文献复习

肾混合性上皮间质肿瘤(mixed epithelial and stromal tumor of the kidney,MESTK)是一种临床罕见的肾良性肿瘤,肿瘤成份由间质和上皮混合构成。MESTK的临床表现不典型,影像学上多表现为BosniakⅢ和Ⅳ级囊性病变,明确诊断依靠病理活检及免疫组化,临床易误诊为肾癌囊性变或多房囊性肾肿瘤。本文回顾性分析总结了1例孤立肾合并MESTK患者的临床资料,并对该疾病诊疗进展作文献复习。

Traditional Chinese medicine integrated with chemotherapy for stage Ⅳ non-surgical gastric cancer: a retrospective clinical analysis

OBJECTIVE： Traditional Chinese medicine （TCM） is regarded as an important treatment for gastric cancer patients, especially for those in advanced stage. To evaluate the effects of TCM treatment on gastric cancer patients, the authors performed a retrospective study to report the result of the integrated treatment of TCM with chemotherapy for stage IV non-surgical gastric cancer. METHODS： In this study, 182 patients with stage IV and non-surgical gastric cancer were retrospectively analyzed to evaluate the effects of TCM integrated with chemotherapy. Among the 182 cases, 88 cases received integrated therapy consisting of TCM and chemotherapy, while 94 cases received chemotherapy alone. The overall survival and Karnofsky performance status （KPS） score were measured as the main outcome. RESULTS： The median overall survival of the integrated therapy group and chemotherapy group were 16.9 and 10.5 months, respectively. The 1-, 3- and 5-year survival rates of integrated therapy group vs. chemotherapy group were 70% vs. 32%, 18% vs. 4%, and 11% vs. 0%, respectively. There was a significant difference between the two groups （x2 = 42.244, P 〈 0.001 ）. After six-month treatment, KPS scores of the integrated therapy group and the chemotherapy group were 75.00 ± 14.78 and 60.64 ± 21.39, respectively （P 〈 0.001）. The Cox regression analysis showed that TCM treatment is a protective factor for patients＇ overall survival. CONCLUSION： This study demonstrated that TCM integrated with chemotherapy may prolong overal survival and improve survival rate and life quality of patients with stage IV non-surgical gastric cancer

浅蓝霉素H的发酵优化与浅蓝苷K的化学合成

浅蓝霉素H (2)及其4-基α-L-吡喃鼠李糖苷[即浅蓝苷K (1)]是从海洋来源的浅蓝异壁放线菌WH1-2216-6的发酵产物中分离获得的天然产物,浅蓝苷K(1)具有良好的肿瘤细胞增殖抑制活性,但其产率低,合成未见报道.因此,首先对浅蓝霉素H(2)的主产菌株浅蓝异壁放线菌WH1-2216-6突变株CRM05进行发酵优化,采用放线菌5号与玉米配制的固体培养基发酵培养CRM05菌株,将浅蓝霉素H (2)的产量提高到272 mg/L(提高了5倍),获得了足量的浅蓝霉素H(2).接着,通过脱肟、鼠李糖苷化、成肟及脱乙酰保护等6步反应,以25.6%的总收率从浅蓝霉素H(2)合成了浅蓝苷K (1).通过高分辨质谱、核磁共振和比旋光等数据确认了浅蓝苷K (1)的结构,与报道的天然产物为同一化合物.浅蓝苷K (1)具有较强的肿瘤细胞抗增殖活性,对肿瘤细胞株PATU8988T、786-O、5673、DU145、A-375、FaDu和SF126的半数抑制浓度(IC50)为1.07~1.78μmol/L.

Development and current clinical application of ventricular assist devices in China

Heart failure has become one of the biggest threats to human health. Transplantation remains the most effective therapy for heart failure, but because of the shortage of donors, it cannot meet the demand. Ventricular assist devices （VADs） were developed to treat heart failure, and have now been clinically applied worldwide. As the country with the largest population, China is also facing the threat of heart failure. However, the development of VADs in China is very slow and is seldom discussed. This paper first talks about the background for VAD development in China. Then several home-developed VADs in China are introduced. The current clinical application status of VADs in China is also presented. Finally the challenge and opportunity for VAD development in China are discussed.