A Case of Multi-Stage Fracturing Horizontal Well Used in BZ Oilfield in Bohai Bay Low-Permeability Oilfield Development

BZ oilfield in Bohai Bay of China was a typical offshore low permeability oilfield, which was restricted by many factors such as environment and economy. In this paper, the development characteristics of BZ oilfield were summarized in depth, and the new development mode of offshore low-permeability oilfield was explored from reservoir prediction, well spacing and fracturing technology. Taking BZ oilfield as an example, a set of technical system for the effective development of offshore low permeability oilfield had been formed through research, which mainly includes reservoir prediction and evaluation of offshore middle and deep low permeability oilfield, optimization of horizontal well pattern, multi-stage fracturing design of horizontal well and other technologies. The results show that improving the resolution of seismic data, strengthening the analysis of seismic reflection characteristics and carrying out the comprehensive study of seismic geology were the keys to solve the reservoir prediction of offshore low-permeability oil fields. Multi-stage fracturing horizontal well pattern is the main pattern of offshore low-permeability oilfield development. The parameters of multi-stage fracturing horizontal well together affect the development effect. Selecting the optimal fractured horizontal well pattern can greatly improve the development effect. The successful combination and application of new technology system was the foundation and core of conquering offshore low-permeability oil fields. On the basis of understanding the geological characteristics of oil reservoirs, it is an effective means of developing offshore low-permeability oil fields by selecting reasonable production methods, well types and well patterns. Using efficient perforation and fracturing technology to successfully control fracture parameters and form optimal injection and production well pattern was the key to improve low permeability offshore oil fields.

Study on Water Ridge Variation of Horizontal Wells in Bottom Water Reservoir

X oilfield is a typical strong bottom water reservoir in Bohai Sea. It is developed by single sand body horizontal well. The edge and bottom water of the reservoir is active and natural energy development mode is adopted. At present, the comprehensive water cut of the oilfield is more than 96%, and has entered the stage of high water cut oil recovery. At present, fluid extraction from old wells and new adjustment wells are the main ways to increase oil production. With the deepening of development, the distribution of underground remaining oil is becoming more and more complex. In order to further improve the implementation effect of adjustment wells, the study of residual oil distribution law is increasingly important, and the study of water ridge morphology of horizontal wells in bottom water reservoir has an important guiding role in the study of remaining oil distribution. The main contents of this paper are as follows: the influence of horizontal well spacing, vertical and horizontal permeability ratio, single well liquid production, vertical position of horizontal well, oil-water viscosity ratio, water cut and interlayer on water ridge morphology. These understandings can effectively guide the deployment and optimization of adjustment wells. It provides technical support for the prediction of watered out thickness and optimization of adjustment well layout scheme in X oilfield, and guides the further development and production of the oilfield.

Evaluation of Early High Speed Development of Bottom Water Heavy Oil Reservoir

The bottom water heavy oil reservoir has high natural energy, and the bottom water body multiple of the reservoir is 300 times or even higher. The natural energy of the reservoir can keep the superior condition that the formation energy does not decrease under the condition of large liquid volume and high recovery rate. In view of this reservoir condition, we take C oilfield as an example to carry out the oilfield development effect under the condition of large liquid volume and high-speed production, and analyze the influence of high-speed production and medium low-speed production on recovery rate of similar heavy oil bottom water-reservoir. The results show that the rising trend of water cut in oilfield is the same whether high-speed development with large liquid volume or conventional low-speed development is adopted. Under the condition of high liquid production, the sweep efficiency of water flooding is high in the same period of time, which has certain advantages of enhanced oil recovery. The development mode of early large liquid production is explored, which provides certain guidance for the efficient development of heavy oil reservoir with bottom water.

3D打印个体化模具在宫颈癌近距离治疗中的应用

目的:通过3D打印个体化模具辅助插植,降低宫颈癌近距离治疗难度。方法:前瞻性研究2019年6月至2020年7月30例于重庆大学附属肿瘤医院行根治性放化疗宫颈鳞状细胞癌患者,随机分为15例3D打印组(试验组)和15例通用施源器组(对照组)。评估两组治疗情况、靶区适形指数(coformity index,CI)、高危临床靶区(high-risk clinical target area,HR-CTV)90%体积的最低吸收剂量(D90)、危及器官(organs-at-risk,OARs)受量及临床治疗结果。结果:试验组无子宫穿孔,对照组子宫穿孔率为8.97%(7/78)。试验组的CI为0.81±0.01,与对照组的0.61±0.01相比,差异具有统计学意义(P<0.05);试验组HR-CTV D90及膀胱的分次/总外照射等效剂量(equivalent dose in 2 Gy per fraction,EQD2)分别为6.65±0.06/91.84±1.35及3.75±0.07/71.02±1.39,与对照组的6.17±0.06/88.59±0.11及4.09±0.07/74.81±1.50相比,差异均具有统计学意义(均P<0.05)。试验组直肠及乙状结肠的受量降低,差异无统计学意义(P>0.05),试验组治疗结束后3个月完全缓解(complete response,CR)率为93.33%(14/15),与对照组的86.67%(13/15)相比,差异具有统计学意义(P<0.05)。结论:3D打印个体化模具在辅助宫颈癌近距离插植治疗中有明显的优势,操作简单、安全性高、有利于组织间插植技术推广。

FIGO 2018分期系统对子宫颈神经内分泌癌治疗及预后的影响

目的:探讨国际妇产科联盟(FIGO)2018分期系统对子宫颈神经内分泌癌(neuroendocrine carcinoma of the uterine cervix,NECUC)患者治疗决策及预后的影响。方法:回顾性分析2003年1月至2019年1月65例收治于重庆大学附属肿瘤医院的NECUC患者的临床病理资料,按照FIGO 2018新分期系统再分期,与FIGO 2009老分期系统进行比较,并对预后进行单因素和多因素分析。结果:65例NECUC患者的中位发病年龄为46(18~70)岁,中位随访时间为23.6(4~151)个月,其中42例行根治性手术、16例行同步放化疗、3例行单纯化疗、4例拒绝治疗。截止随访时42例出现复发转移,38例死亡。按照FIGO 2018新分期系统进行再分期后,65例患者中有34例(52.3%)分期升级,大多数变化出现在ⅠB期和ⅢC期。患者的2年累积无进展生存(progression-free survival,PFS)率和总生存(overall survival,OS)率分别为40.5%和50.5%。单因素分析显示预后与FIGO分期、放疗、化疗及化疗疗程有显著性相关(均P<0.05),而与肿瘤大小、化疗方案无显著性相关(均P>0.05);多因素分析显示是否行放疗是PFS的独立影响因素,而FIGO 2018新分期系统及化疗疗程是OS的独立影响因素。结论:FIGO 2018新分期系统对于判断NECUC预后要优于老分期系统,对于早期患者术前影像学评估淋巴结状态尤为重要,足疗程的化疗及放疗可能对改善患者的生存有益。

Relationship between full-thickness macular hole and retinal break/lattice degeneration

Background: The purpose is to investigate the relationship between full-thickness macular hole(MH) and retinal break(RB) and/or lattice degeneration.Methods: Patients diagnosed as full-thickness MH and referred to Dr. Lin Lu from January 2009 to December 2013 were evaluated. All patients underwent general ophthalmologic examinations, fundus examination and optical coherence tomography(OCT). The RB and/or lattice degeneration were recorded.Results: Totally 183 eyes of 167 patients were included. The sex ratio of men to women was 1:2.88. A total of 17 eyes were pseudophakic and 166 eyes were phakic. RB and/or lattice degeneration were found in 62 eyes(33.88%). The prevalence of RB and/or lattice degeneration was similar between men and women(P=0.344>0.05). There was no statistical difference between the pseudophakic eyes and phakic eyes(P=0.138>0.05). All of the RB and/or lattice degeneration were located near or anterior to the equator. The inferior quadrants and the vertical meridian were af ected more often than the superior quadrants and the horizontal meridian.Conclusions: We identified a high incidence of RB/lattice degeneration in cases of full-thickness MH. Carefully examination of the peripheral retina and prophylactic treatment of RB and/or lattice degeneration are critical.

阴道消除量联合放化疗对巨块型ⅢB期宫颈鳞癌的疗效分析

目的:观察阴道消除量在巨块型ⅢB期宫颈鳞癌治疗中的有效性及安全性。方法:回顾性分析2016年1月至2017年6月49例于重庆大学附属肿瘤医院收治的巨块型ⅢB期宫颈鳞癌患者的临床资料,行阴道消除量+同步放化疗,采用Kaplan-Meier法进行生存分析,采用Cox比例风险回归模型进行预后多因素分析。结果:中位随访时间为36.0个月,完全缓解率为83.7%(41/49),局部复发率为4.1%(2/49),远处转移率为34.7%(17/49)。3年总生存(overall survival,OS)率为76.6%、无病生存(disease free survival,DFS)率为26.7%、无远处转移生存(distant metastais free survival,DMFS)率为26.7%、局部控制率(local control rate,LCR)为77.8%。出现的3~4级急性期不良反应中骨髓抑制占40.82%(20/49)、腹泻占20.41%(10/49)、尿频占6.12%(3/49);出现的3~4级晚期不良反应中放射直肠炎占20.41%(10/49)、膀胱炎占8.16%(4/49)。多因素分析采用Cox比例风险回归模型显示放疗时程影响OS、LCR(P<0.05),A点EQD2剂量影响DMFS、LCR(P<0.05),同步放化疗后鳞状细胞癌相关抗原SCC未转阴者复发率为61%(11/18)。结论:巨块型ⅢB期宫颈鳞癌患者在阴道消除量联合放化疗中生存获益,但直肠、膀胱的不良反应增加,建议个体化治疗。放疗时程是宫颈癌预后的独立因素,SCC可用于宫颈癌随访及监测复发。

Investigation of the Relation between Rolling Contact Fatigue Property and Microstructure on the Surface Layer of D2 Wheel Steel

Through the rolling contact fatigue experiment under the condition of the lubricating oil, this article investigated the relation between contact fatigue property and microstructure on the surface layer of D2 wheel steel. The results showed that although the roughness of the original specimen induced by mechanical processing would diminish to some extent in the experiment, the 0.5 - 1.5 μm thick layer of ultrafine microstructure on the original mechanically-processed specimen surface would still become micro-cracks and small spalling pits due to spalling, and would further evolve into fatigue crack source. Additionally, even under the impact of the load that was not adequate to make the material reach fatigue limit, the ferrite in the microstructure underwent plastic deformation, which led the refinement of proeutectoid ferrite grains. During the experiment, the hardening and the refinement caused by plastic deformation consisted with the theory that dislocation gave rise to plastic deformation and grain refinement. The distribution laws of hardness and ferrite grain sizes measured could be explained by the distribution law of the shearing stress in the subsurface.

Ultrasonic Characteristics and Severity Assessment of Lung Ultrasound in COVID-19 Pneumonia:A Retrospective,Observational Study

The clinical application of lung ultrasound(LS)in the assessment of coronavirus disease 2019(COVID-19)pneumonia severity remains limited,Herein,we investigated the role of LUS imaging in CoVID-19pneumonia patients and the relationship between LUS findings and disease severity.This was a retro-spective,observational study at Tongji Hospital,on 48 recruited patients with COVID-19 pneu-monia,including 32 non-critically ill patients and 16critically ill patients.LUS was performed and the respiratory rate oxygenation(ROX)index,disease severity,and confusion,blood urea nitrogen,respira-tory rate,blood pressure,and age(CURB-65)score were recorded on days 0-7,8-14,and 15-21 after symptomonset.Lung images were divided into 12 regions,and the luS score(0-36 points)was calcu-lated.hestcomputed tomography(CT)scores(0-20 points)were also recorded on days O-7.Coelations between the LUS score,ROX index,and CURB-65 scores were examined.LUS detected COVID-19 pneumonia in 38patients.LUS signs included B lines(34/38,89.5%),consolidations(6/38,15.8%),and pleural effusions(2/38,5.3%).Most cases showed more than one lesion(32/38,84.2%)and involved both lungs(28/38,73.7%).Compared with non-critically ill patients,the LUS scores of critically ill patients were higher(12(10-18)vs 2(0-5),p<0.001).The LUS score showed significant negative cor-relations with the ROX indexon days O-7(r=-0.85,p<0.001),days 8-14(r=-0.71,p<0.001),and days 15-21(r=-0.76,p<0.001)after symptom onset.However,the LUS score was positively correlated with the CT score(r=0.82,p<0.001).The number of patients with LUS-detected lesions decreased from 27 cases(81.8%)to 20 cases(46.5%),and the lus scores significantly decreased from 4(2-10)to 0(0-5),(p<0.001) from days O-7 to 17-21.We conclude that LUS can detect lunglesions in COVID-19 pneumo-nia patients in a portable,real-time,and safe manner.Thus,LUS is helpful in assessing COVID-19 pneu-monia severity in critically ill patients.

A Review of Air Pollution and Control in Hebei Province, China

Hebei is one of the most air polluted provinces in China. According to the Ministry of Environmental Protection (MEP) for the severe fog-haze month of Jan. 2013, seven of the top ten most polluted cities in China are located in Hebei Province. In this study, the air pollution history and status of the Hebei Province are reviewed and discussed, using the governmental published Air Pollution Index (API), the academic observations by various scientific research groups and the long-term statistics of visibility and haze frequencies. It is found that within the Hebei Province, the air pollution in the southern cities is much more severe than the northern cities. Particulate matter (PM) is undoubtedly the major air pollutant, sulfur dioxide (SO2) and nitrogen oxides (NOX) pollutions are also unnegligible. Ozone (O3) pollution in larger cities, such as Shijiazhuang, is significant. Air pollution control history from 1998 is discussed as well. Although Hebei Province has made a great effort on air quality, the pollutant emissions, such as SO2 and fly ash, showed a notable increase in 2001 to 2006. However, after 2006 the emissions started to decrease due to the strict implementation of the national 11th Five Year Plan (FYP). In addition, regional jointly air pollution control and prevention strategies are expected in the future to substantially change the severe air pollution status in Hebei Province.

Preventive Effect of Xiangsha Yangwei Pills on the Novel Coronavirus Pneumonia from"Genuine Qi Exists,Illness Never"

The preventive effect of traditional Chinese medicine on the novel coronavirus(COVID-19)pneumonia is embodied in the"prevention before disease onset"of"treatment of disease"theory of thought,and it is considered that the key to the success or failure of prevention is whether the healthy qi is abundant or not.This article discusses and understands the"genuine qi"from the The Medical Classic of the Yellow Emperor,and describes its meaning comprehensively and systematically,combining with the expansion and supplement of many doctors in later generations.The"genuine qi"includes healthy qi,pulse qi,congenital qi,personal qi,Jing qi primordial qi and food energy,all of which are closely related to spleen-stomach.The function of spleen-stomach is normal,water and grain are transported properly,and the rise and fall of qi is appropriate,then the human body's qi is abundant,the anti-evil force is strong,and people are not easy to cause disease;even if the disease,the prognosis is better.This the novel coronavirus pneumonia comprehensive analysis,belongs to the traditional Chinese medicine science"damp-toxin epidemic",therefore the prevention should pay more attention to strengthen spleen and stomach,eliminate dampness,and Xiangsha Yangwei Pills is the appropriate choice.

Effect of Sliding Wear on Surface Microstructure and Wear Property of D2 Wheel Steel

In this paper, the surface microstructure and wear property of D2 wheel steel under sliding wear condition were studied by MRH-30 sliding wear tester. After testing, a transmission electron microscope (TEM), scanning electron microscope (SEM) with electron backscatter diffraction (EBSD), and micro-hardness testers were used to characterize the surface microstructure of samples with different cycles. The results show that the wear losss samples are increased as the increase of cycles, and the wear loss of wheel samples is higher than that of rail samples. The surface hardness and thickness of deformation layer of wheel samples are increased as the cycles increase. After sliding wear, the samples surfaces form the white etching layer with the thickness of several microns. Through the analysis of surface microstructure of sample with 12,000 cycles, the lamellar cementite in pearlite is fragment into cementite particles with the decrease of depth from surface, and the cementite is dissolved at surface to lead to the form of white etching layer. The ferrite grains are refined gradually and the fraction of high angle grain boundary is increased with the decrease of depth from surface. The nanosgrains layer of ferrite grains with 5 μm thickness is formed. According to the result of finite element simulation of contact surface temperature, the formation of surface nanograins and the dissolution of cementite are caused by the severe plastic deformation. The fiber structure of samples is formed after sliding wear, with direction of .

Revisiting influenza A virus life cycle from a perspective of genome balance

Influenza A virus(IAV)genome comprises eight negative-sense RNA segments,of which the replication is well orchestrated and the delicate balance of multiple segments are dynamically regulated throughout IAV life cycle.However,previous studies seldom discuss these balances except for functional hemagglutinin-neuraminidase balance that is pivotal for both virus entry and release.Therefore,we attempt to revisit IAV life cycle by highlighting the critical role of“genome balance”.Moreover,we raise a“balance regression”model of IAV evolution that the virus evolves to rebalance its genome after reassortment or interspecies transmission,and direct a“balance compensation”strategy to rectify the“genome imbalance”as a result of artificial modifications during creation of recombinant IAVs.This review not only improves our understanding of IAV life cycle,but also facilitates both basic and applied research of IAV in future.

Optimization and applications of an in vivo bioluminescence imaging model of influenza A virus infections

Dear Editor,In vivo bioluminescence imaging(BLI)models of virus infection possess unique advantages over conventional assays.For instance,the BLI model enables rapid and real-time detection of viral load and dissemination in the same animal over time(Mehle,2015;Wen et al.,2022).

Relationships Between Evacuation Population Size, Earthquake Emergency Shelter Capacity, and Evacuation Time

Determining the location of earthquake emergency shelters and the allocation of affected population to them are key issues that face shelter planning and emergency management. To solve this emergency shelter location–allocation problem, evacuation time and the construction cost of shelters—both influenced by the evacuation population size and its spatial distribution—are two important considerations. In this article, a mathematical model with two objectives—to minimize total weighted evacuation time(TWET) and total shelter area(TSA)—is allied with a modified particle swarm optimization algorithm to address the problem. The relationships between evacuation population size, evacuation time, and total shelter area are examined using Jinzhan Town in Chaoyang District of Beijing, China, as a case study. The results show that TWET has a power function relationship with TSA under different population size scenarios, and a linear function applies between evacuation population and TWET under different TSAs. The joint relationships of TSA, TWET, and population size show that TWET increases with population increase and TSA decrease, and compared with TSA, population influences TWET more strongly. Given a reliable projection of population change and spatial planning of a study area, this method can be useful for government decision making on the location of earthquake emergency shelters and on the allocation of evacuees to those shelters.

Polycomb-group proteins in the initiation and progression of cancer

The Polycomb group(PcG) proteins are a family of chromatin regulators and critical for the maintenance of cellular identity. The PcG machinery can be categorized into at least three multi-protein complexes, namely Polycomb Repressive Complex 1(PRC1), PRC2, and Polycomb Repressive De UBiquitinase(PR-DUB).Their deregulation has been associated with human cancer initiation and progression. Here we review the updated understanding for Pc G proteins in transcription regulation and DNA damage repair and highlight increasing links to the hallmarks in cancer. Accordingly, we discuss some of the recent advances in drug development or strategies against cancers caused by the gain or loss of PcG functions.

Pollution levels, composition characteristics and sources of atmospheric PM2.5 in a rural area of the North China Plain during winter

The pollution levels,composition characteristics and sources of atmospheric PM2.5 were investigated based on field measurement at a rural site in the North China Plain(NCP) from pre-heating period to heating period in winter of 2017.The hourly average concentrations of PM2.5 frequently exceeded 150 μg/m3 and even achieved 400 μg/m3,indicating that the PM2.5pollution was still very serious despite the implementation of stricter control measures in the rural area.Compared with the pre-heating period,the mean concentrations of organic carbon(OG),element carbon(EC) and chlorine ion(Cl-) during the heating period increased by 20.8%,36.6% and 38.8%,accompanying with increments of their proportions in PM2.5from 37.5%,9.8% and 5.5% to 42.9%,12.7% and 7.2%,respectively.The significant increase of both their concentrations and proportions during the heating period was mainly ascribed to the residential coal combustion.The proportions of sulfate,nitrate and ammonium respectively increased from 9.9%,10.9% and 9.0% in nighttime to 13.8%,16.2% and 11.1% in daytime,implying that the daytime photochemical reactions made remarkable contributions to the secondary inorganic aerosols.The simulation results from WRF-Chem revealed that the emission of residential coal combustion in the rural area was underestimated by the current emission inventory.Six sources identified by positive matrix factorization(PMF) based on the measurement were residential coal combustion,secondary formation of inorganic aerosols,biomass burning,vehicle emission and raising dust,contributing to atmospheric PM2.5 of 40.5%,21.2%,16.4%,10.8%,8.6% and 2.5%,respectively.

Impact of emission reduction on aerosol-radiation interaction during heavy pollution periods over Beijing-Tianjin-Hebei region in China

In December 2015,the Beijing-Tianjin-Hebei(BTH) region experienced several episodes of heavy air pollution.The government immediately issued emergency control measures to reduce the pollution,which provided a good opportunity to explore the impact of emission reduction on aerosol-radiation interaction.In this study,four tests were conducted,including the basel simulation with emission reduction and aerosol-radiation interaction on,the base2 simulation with emission reduction and aerosol-radiation interaction off,the scenariol simulation without emission reduction and aerosol-radiation interaction on and the scenario2 simulation without emission reduction and aerosol-radiation interaction off.We find that the aerosol-radiation interaction decreased the downward shortwave radiation and the temperature at 2 m,reduced the planetary boundary layer height(PBLH) in the region,and increased the relative humidity at 2 m,which is favorable for pollution accumulation.Our results revealed that the interaction effect due to emission reductions increased downward shortwave radiation by an average of 0-5 W/m2,leading to increase in surface temperature of 0-0.05℃,increase in the daytime mean PBL high of 0-8 m,and decrease in daytime mean relative humidity at 2 m of 0.5%.We found that if there were aerosol-radiation interaction,it would enhance the effectiveness of emission control measures on air pollution control.The enhance of PM2.5(particulate matter less than 2.5 um),PM10(particulate matter less than 10 um),and NO2(nitrogen dioxide) emission reduction effects reached7.62%,6.90%,11.62%,respectively,over this region.

Oscillation of Surface PM2.5 Concentration Resulting from an Alternation of Easterly and Southerly Winds in Beijing： Mechanisms and Implications

We used simultaneous measurements of surface PM_（2.5） concentration and vertical profiles of aerosol concentration,temperature, and humidity, together with regional air quality model simulations, to study an episode of aerosol pollution in Beijing from 15 to 19 November 2016. The potential effects of easterly and southerly winds on the surface concentrations and vertical profiles of the PM_（2.5） pollution were investigated. Favorable easterly winds produced strong upward motion and were able to transport the PM_（2.5） pollution at the surface to the upper levels of the atmosphere. The amount of surface PM_（2.5） pollution transported by the easterly winds was determined by the strength and height of the upward motion produced by the easterly winds and the initial height of the upward wind. A greater amount of PM_（2.5） pollution was transported to upper levels of the atmosphere by upward winds with a lower initial height. The pollutants were diluted by easterly winds from clean ocean air masses. The inversion layer was destroyed by the easterly winds and the surface pollutants and warm air masses were then lifted to the upper levels of the atmosphere, where they re-established a multi-layer inversion. This region of inversion was strengthened by the southerly winds, increasing the severity of pollution. A vortex was produced by southerly winds that led to the convergence of air along the Taihang Mountains. Pollutants were transported from southern–central Hebei Province to Beijing in the boundary layer. Warm advection associated with the southerly winds intensified the inversion produced by the easterly winds and a more stable boundary layer was formed. The layer with high PM_（2.5） concentration became dee-per with persistent southerly winds of a certain depth. The polluted air masses then rose over the northern Taihang Mountains to the northern mountainous regions of Hebei Province.

Twinned substructure in lath martensite of water quenched Fe-0.2%C and Fe-0.8%C steels

In the present investigation,twinned substructures within lath martensite of two water quenched steels(0.2 wt.%C and 0.8 wt.%C)were studied.The lath martensite has typical hierarchical packet-block-lath with dislocation substructure.Besides,laths that are misoriented by<011>/70.5°or<111>/60° and bordered by{011}plane,namely twinned laths,are observed,of which the density increases and the scale decreases as more carbons were presented.Such twinned laths have body centered cubic(bcc)crystal structure,belonging to twinned variants following the classical Kurdjumov-Sachs(K-S)orientation relationship with respect to the parent austenite.Unlike bcc{112}<111>twins,twinned variants produce strong double diffraction and in turn the extra diffraction spots that are commonly observed in the martensite in steels with wide range of carbon contents.