Effect of navigation endoscopy combined with threedimensional printing technology in the treatment of orbital blowout fractures

●AIM:To explore the combined application of surgical navigation nasal endoscopy(NNE)and three-dimensional printing technology(3DPT)for the adjunctive treatment of orbital blowout fractures(OBF).●METHODS:Retrospective analysis was conducted on the data of patients with OBF who underwent surgical treatment at the Affiliated Eye Hospital of Nanchang University between July 2012 and November 2022.The control group consisted of patients who received traditional surgical treatment(n=43),while the new surgical group(n=52)consisted of patients who received NNE with 3DPT.The difference in therapeutic effects between the two groups was evaluated by comparing the duration of the operation,best corrected visual acuity(BCVA),enophthalmos difference,recovery rate of eye movement disorder,recovery rate of diplopia,and incidence of postoperative complications.●RESULTS:The study included 95 cases(95 eyes),with 63 men and 32 women.The patients’age ranged from 5 to 67y(35.21±15.75y).The new surgical group and the control group exhibited no statistically significant differences in the duration of the operation,BCVA and enophthalmos difference.The recovery rates of diplopia in the new surgical group were significantly higher than those in the control group at 1mo[OR=0.03,95%CI(0.01–0.15),P<0.0000]and 3mo[OR=0.11,95%CI(0.03–0.36),P<0.0000]postoperation.Additionally,the recovery rates of eye movement disorders at 1 and 3mo after surgery were OR=0.08,95%CI(0.03–0.24),P<0.0000;and OR=0.01,95%CI(0.00–0.18),P<0.0000.The incidence of postoperative complications was lower in the new surgical group compared to the control group[OR=4.86,95%CI(0.95–24.78),P<0.05].●CONCLUSION:The combination of NNE and 3DPT can shorten the recovery time of diplopia and eye movement disorder in patients with OBF.

基于虚拟现实技术的井喷抢险模拟平台开发

井喷着火抢险作业的培训模式普遍存在着实地模拟危险性高、视频教学经验积累慢的缺点。有必要开发一个不受时间和场地限制的虚拟现实(Virtual Reality,VR)培训平台。利用Unity3D引擎搭建虚拟井场环境,使用粒子表面渲染和粒子系统实现井喷着火效果模拟,并建立多点源火焰热辐射模型,动态计算人员受到的热辐射伤害,以不同热辐射伤害等级划定安全范围。同时基于分层式复合碰撞体实现救援设备的人机交互和结果事件响应,完成一体化救援流程。结果表明:井喷着火时,安全距离应在70米以上;随着火焰倾角增加,最大安全距离都会向火焰倾向方向不同程度增大,最小安全距离会向火焰倾向的反方向不同程度减小。上述平台的开发建立,对安全救援作业有一定的借鉴意义。

防火围油栏和撇油器在海上井喷溢油处置中的适用性分析及展望

随着我国海上石油勘探开发强度的不断加大,海上井喷溢油事故风险持续增高。针对井喷溢油事故这一最为严重的海洋环境污染事故,有必要结合井喷溢油事故现场可能出现的工况环境和相应的处置策略,对用于处置井喷事故的防火围油栏、撇油器的适用性进行分析。同时通过对比行业内溢油应急设备制造及现今装备制造自动化、智能化的发展动态,明确我国溢油应急设备现状的不足和今后溢油应急设备的发展方向,以达到在井喷溢油这一极端工况下,有效控制和回收溢油、最大限度降低环境污染风险的目的。

Biomechanical analysis of an absorbable material for treating fractures of the inferior orbital wall

AIM:To investigate the biomechanical properties and practical application of absorbable materials in orbital fracture repair.METHODS:The three-dimensional(3D)model of orbital blowout fractures was reconstructed using Mimics21.0 software.The repair guide plate model for inferior orbital wall fracture was designed using 3-matic13.0 and Geomagic wrap 21.0 software.The finite element model of orbital blowout fracture and absorbable repair plate was established using 3-matic13.0 and ANSYS Workbench 21.0 software.The mechanical response of absorbable plates,with thicknesses of 0.6 and 1.2 mm,was modeled after their placement in the orbit.Two patients with inferior orbital wall fractures volunteered to receive single-layer and double-layer absorbable plates combined with 3D printing technology to facilitate surgical treatment of orbital wall fractures.RESULTS:The finite element models of orbital blowout fracture and absorbable plate were successfully established.Finite element analysis(FEA)showed that when the Young’s modulus of the absorbable plate decreases to 3.15 MPa,the repair material with a thickness of 0.6 mm was influenced by the gravitational forces of the orbital contents,resulting in a maximum total deformation of approximately 3.3 mm.Conversely,when the absorbable plate was 1.2 mm thick,the overall maximum total deformation was around 0.4 mm.The half-year follow-up results of the clinical cases confirmed that the absorbable plate with a thickness of 1.2 mm had smaller maximum total deformation and better clinical efficacy.CONCLUSION:The biomechanical analysis observations in this study are largely consistent with the clinical situation.The use of double-layer absorbable plates in conjunction with 3D printing technology is recommended to support surgical treatment of infraorbital wall blowout fractures.

Evaluation of the Customer Satisfaction Index for Wellhead Blowout Preventers of China’s Petroleum Industry——A new method based on PLS

This paper establishes an evaluation model of the customer satisfaction index for the wellhead blowout preventers of China＇s petroleum industry based on evaluation models of the customer satisfaction index at home and aboard, and by considering the consuming situation in China and the features of the China＇s petroleum industry. For the existence of： （1） multiple correlations among the factors in the model; （2） the variables need to be explained, but that are hard to observe; （3） the customer satisfaction degree of observation variables appears the shape of skewness or two or three peaks, the correlations between the satisfaction index and its factors cannot be described by common multiple regression. This paper uses a partial least squares （PLS） method based on principal components and typical correlative analysis to solve the problem. When PLS is used in the model of the customer satisfaction index of the wellhead blowout preventers, the latent variables and the explanation degree coefficient of the manifest variable to the corresponding latent variables are estimated by PLS path analysis, and the influencing coefficient among the latent variables in the model is estimated by PLS regression analysis. PLS is also be used to calculate and analyze the model and disclose the correlations among the structural variables as well as the correlation between structural variables and its corresponding observation variables, evaluating results of which provide useful information for petroleum industry to improve the product quality and to the enhancement of the customer satisfaction to the product.

Analysis of the effect of repair materials for orbital blowout fracture on complications

AIM: To investigate the effect of repair materials for orbital blowout fractures on the occurrence of postoperative complications. METHODS: The clinical data and follow-up data of 54 subjects with orbital blowout fractures were retrospectively analyzed. The study was divided into three groups according to the used repair materials: titanium mesh(16 cases), Medpor(12 cases), and Medpor titanium mesh(26 cases). All test data were analyzed using the SPSS version 23.0 statistical software. The mean age and duration of disease between the groups were compared through oneway analysis of variance. The Chi-square(χ~2) test was used to compare the number of males and females, different fracture types, and different surgical approaches among groups. The χ~2 test was used to compare the frequencies for complications in each group.RESULTS: The baseline characteristics of age and gender in each group were matched(F=1.763, P=0.172;χ~2=0.026, P=0.987). In addition, there was no difference in the type of fracture and surgical approach(χ~2=0.460, P=0.977;χ~2=0.691, P=0.952), or the incidence of complications(χ~2=0.081, P=0.960) between the three groups. CONCLUSION: Although there is no difference in effect of various repair materials on the incidence of complications, the effect of repair materials on postoperative complications of orbital blowout fractures should not be ignored.

Landscape pattern change and driving force of blowout distribution in the Hulun Buir Sandy Grassland

The land coverage pattern changes for the past 50 years in a typical region of the Hulun Buir Sandy Grassland were interpreted and analyzed based on a series of remote sensing images in 1959, 2002, 2004 and 2009. The temporal and spatial changes of landscape patterns were revealed and the driving forces were analyzed. The results show that all land coverage types had large variable amplitudes. The grassland area decreased, whereas other areas incleased. Owing to implementation of artificial sand fixation from 2004 to 2009, the areas of flowing blowouts and depositional area decreased by 71,369 and 128,835 m2, respectively. The average patch area reduced, but the number of blowouts increased, fractal dimension increased, and blowout structure became complex. The fragmentation index increased, whereas contagion index decreased. Driving force analysis shows that human factors such as overglazing are slightly larger than natural factors of increased temperature and decreased precipitation

Numerical Simulation of Water and Sand Blowouts When Penetrating Through Shallow Water Flow Formations in Deep Water Drilling

In this study, we applied a two-phase flow model to simulate water and sand blowout processes when penetrating shallow water flow(SWF) formations during deepwater drilling. We define ‘sand' as a pseudo-component with high density and viscosity, which can begin to flow with water when a critical pressure difference is attained. We calculated the water and sand blowout rates and analyzed the influencing factors from them, including overpressure of the SWF formation, as well as its zone size, porosity and permeability, and drilling speed(penetration rate). The obtained data can be used for the quantitative assessment of the potential severity of SWF hazards. The results indicate that overpressure of the SWF formation and its zone size have significant effects on SWF blowout. A 10% increase in the SWF formation overpressure can result in a more than 90% increase in the cumulative water blowout and a 150% increase in the sand blowout when a typical SWF sediment is drilled. Along with the conventional methods of well flow and pressure control, chemical plugging, and the application of multi-layer casing, water and sand blowouts can be effectively reduced by increasing the penetration rate. As such, increasing the penetration rate can be a useful measure for controlling SWF hazards during deepwater drilling.

Role of orthoptics and scoring system for orbital floor blowout fracture:surgical or conservative treatment

AIM:To assess the role of orthoptics in referring patients with orbital floor blowout fracture(OFBF)for conservative or surgical treatment and based on the results,to propose a scoring system for such decision making.METHODS:A retrospective analysis of 69 patients with OFBF was performed(35 treated conservatively,34 surgically).The role of orthoptics in referring to surgery or conservative treatment was retrospectively evaluated,the factors with the highest significance for decision making were identified,and a scoring system proposed using Logistic regression.RESULTS:According to defined criteria,the treatment was unsuccessful in 2(6%)surgically treated and only in one(3%)conservatively treated patient.The proposed scoring system includes the defect size and several values resulting from the orthoptic examination,the elevation of the eyebulb measured on Lancaster screen being the most significant.CONCLUSION:The study demonstrates the benefits of orthoptic examination when making decisions on conservative or surgical treatment and for diagnosing ocular motility disorder(with or without binocular diplopia)in OFBF patients.The proposed scoring system could,following verification in a prospective study,become a valuable adjunctive tool.

A Real-time Monitoring System for Tire Blowout or Severe Leakage

The tire blowout or severe leakage real-time monitoring is one of key technologies for developing a tire blowout automatic braking system.An indirect real-time monitoring method to fuse analyses of tire vibration and effective radius is provided in this paper,and a monitoring system is developed.The calibration and related test results showthat the system can detect the tire blowout in low and middle vehicle speeds and the severe leakage in all speeds timely and accurately.

Carotid blowout syndrome caused by chronic infection:A case report

BACKGROUND Carotid blowout syndrome(CBS)refers to rupture of the extracranial carotid artery and its branches;as a severe complication,it usually occurs after surgery or radiotherapy for malignant tumours of the head and neck.We present a case of CBS caused by chronic infection of the external carotid artery(ECA).In this case,we did not find any evidence of head and neck tumours.CASE SUMMARY A 42-year-old man was referred to the Emergency Department with a complaint of a lump found on the left side of his neck with pain and fever for 4 d.We diagnosed the condition as neck infection with abscess formation based on physical examination,routine blood examination,ultrasound examination and plain computed tomography(CT)and decided to perform emergency surgery.During the operation,30 mL of grey and smelly pus was drained from the deep surface of the sternocleidomastoid muscle.The second day after the operation,the patient suddenly exhibited a large amount of haemoptysis and incision bleeding.The enhanced CT showed distal occlusion of the left ECA and irregular thickening of the broken ends of the artery encased in an uneven enhancement of soft tissue density.Infected ECA occlusion and rupture were considered.The patient was transferred to a vascular unit for transcatheter ECA embolization and recovered well.CONCLUSION Surgeons need to pay attention to vascular lesions caused by chronic infection that may develop into acute CBS.

Gas Blowout Impacts on Ground Water Environs around the Tengratila Gas Field, Chattak, Bangladesh

Gas blowout is one of the major hazard in petroleum field which normally damages the gas bearing geologic formation, structure, local tectonic setting, environment and so on. In Bangladesh, there have been three well known gas blowouts. Among them, the most dangerous gas well blowout took place on 8 January 2005 in Sunamganj district when chattak-2 (also known as Tengratila) gas field was drilled. As a result, the surrounding area is facing various problems among them water is the top of the list. From this point of view, the present study has been considered to find the impact of blowout on water around the gas blowout area. In this regard, the water samples (some are very near and some are away from the well) are collected and analyzed in the laboratory following the standard method. Some physical and chemical parameters of water such as pH, turbidity, EC, total solids, dissolved solids, suspended solids, manganese ion, calcium ion, magnesium, iron, chloride and total hardness have measured where without turbidity, manganese and iron, all are still in tolerable state for all purposes and ranging within standard limit based on WHO, EU and EQS for Bangladesh. The quality of the near well tube wells water is much decreased than far away tube wells water which might be the direct or indirect influence of the blowout incident around the area.

Off-Pump Multilayered Sutureless Repair for a Left Ventricular Blowout Rupture after Aortic Dissection Repair

A left ventricular (LV) free wall rupture is a highly lethal condition. A 75-year-old female who experienced chest pain was diagnosed as having an acute aortic dissection Stanford type A and underwent emergent surgery. Under cardiopulmonary bypass with LV venting through the right superior pulmonary vein, a proximal aortic stamp was formed. The patient was cooled, selective antegrade brain perfusion was performed, and a hemiarch repair was performed. After the patient was transferred to the intensive care unit, her blood pressure suddenly fell to 50 mmHg. She had a blowout rupture in the left ventricular anterolateral free wall. Since the bleeding hall was not large and the damage to the surrounding left ventricular tissue was not very wide, an off-pump multilayered sutureless repair was performed by using three layers of collagen fleece squares with fibrinogen-based impregnation (TachoComb;CSL Behring, Tokyo, Japan) and three layers of gelatin-resorcin-formalin glue reinforced by an equine pericardial patch (Xenomedica;Edwards Lifesciences, LLC, Irvine, CA). The blow-out rupture seemed to be caused by perioperative myocardial infarction generated by the compression of the left ventricular vent to the LV lateral wall. The patient was free from re-rupture or aneurysm enlargement. The thickness of the hemostatic material seemed to help control the bulging of the aneurysm and to prevent further LV aneurysm enlargement and re-rupture.

罐式煅烧炉内石油焦热解挥发分迁移路径影响机制

采用计算流体力学(CFD)技术构建罐式炉煅烧石油焦过程仿真模型,研究不同因素对罐内压力及挥发分走向的影响规律。研究结果表明:(1)颗粒粒度是控制罐内压力和挥发分走向的最重要且最有效的因素。当等效粒径d_(p)为1 mm时,在L2~L8火道对应的料罐区域,罐内处于正压状态,挥发分热解气体存在向下迁移趋势,易造成“下火放炮”炉况异常。(2)适当提高火道温度、降低单位排料量和挥发分含量也是抑制“下火放炮”炉况异常的有效措施。火道温度越高,料罐中心的压力越低,料罐出口的热解气体泄漏量也随之降低。单位排料量和挥发分含量越大,料罐中心的压力也越大,料罐出口的热解气体泄漏量也相应增加。研究成果可为揭示“下火放炮”的本质,确保罐式炉稳定运行及节能降耗提供理论基础。

油气井井喷失控着火应急救援技术及发展方向

井喷失控是石油天然气工业领域性质严重、损失巨大的灾难性事故,尤其是“三高井”井喷失控着火后,井口火势大、热辐射高、流体冲击强,对抢险技术、装备及作业安全的要求极高,导致处置过程极其复杂、周期极其漫长。为了充分认识“三高井”井喷失控着火后的处置难点,以井喷失控着火应急救援技术与装备为研究对象,分析了技术发展历程、技术现状、发展方向,创新研究形成了从险情侦察、冷却掩护、清障切割到井口重置的全系列陆上井喷应急救援特色技术。研究结果表明:(1)我国井喷失控着火应急救援技术目前已完成由早期缺少专业技术与装备向近井口高危区域无人化迭代升级;(2)形成的险情侦察技术、冷却掩护技术、清障切割技术、井口重置技术能够满足105 MPa、1000×10^(4)m^(3)/d的高压高产井失控抢险需要;(3)运用相关研究成果成功处置了国内外多起井喷失控、着火及井口刺漏等井控险情,技术能力达到国际先进水平。结论认为:虽然国内陆上油气井井喷失控着火应急救援技术水平已得到大幅度提升,但未来仍需要在可视化、智能化、信息化方面持续攻关,推动技术与装备迈上新台阶。

BOP shear force evaluation under complex scenarios

As the“throat”of the drilling well control system,ram blowout preventers(BOPs)can effectively prevent blowout accidents.However,the ram shear mechanism under complex working conditions is unclear,and it is difficult to evaluate the ram BOP shear force,leading to frequent shear failure accidents in oilfields.Aiming at the above problems,this paper takes the double-V ram BOP as the research object,and integrates the methods of theoretical analysis,simulation modeling,and test verification to analyze the shear force in the pipe shear process under both static and moving conditions.A ram BOP shear force evaluation method is proposed based on equivalent stress.Finally,by comparing with calculation data and experimental data,the error between them is less than 5%,demonstrating the applicability and effectiveness of the proposed method.The research results can provide a theoretical basis for oilfield operations of ram BOPs.

Ignition and Lean Blowout Characteristics of a Reverse-Flow Combustor for an Ultra-Compact Gas Turbine Engine

The flame stability limit and propagation characteristics of a reverse-flow combustor without any flame-stabilized device were experimentally investigated under room temperature and pressure.The results indicate that it is feasible to stabilize the flame in the recirculation zones constructed by the impact jet flow from the primary holes and dilution holes.The flame projected area is mainly distributed in the recirculation zone upstream of the primary holes,whose presence and absence mark the ignition and extinction.During the ignition process,the growth rate and value of the flame projected area first increase and then decrease with the inlet velocity increasing from 9.4 m/s to 42.1 m/s.A rapid reduction followed by a slow reduction of ignition and lean blowout equivalence ratios is achieved by the increased inlet velocity.Then the non-reacting fluid structure in three sections was measured,and detailed velocity profiles were analyzed to improve the understanding of the flame stabilization mechanism.The results are conducive to the design of an ultra-compact combustor.

An LSTM-based approach to detect transition to lean blowout in swirl-stabilized dump combustion systems

Lean combustion is environment friendly with low NO_(x)emissions providing better fuel efficiency in a combustion system.However,approaching towards lean combustion can make engines more susceptible to an undesirable phenomenon called lean blowout(LBO)that can cause flame extinction leading to sudden loss of power.During the design stage,it is quite challenging for the scientists to accurately determine the optimal operating limits to avoid sudden LBO occurrences.Therefore,it is crucial to develop accurate and computationally tractable frameworks for online LBO prediction in low NO_(x)emission engines.To the best of our knowledge,for the first time,we propose a deep learning approach to detect the transition to LBO in combustion systems.In this work,we utilize a laboratory-scale swirl-stabilized combustor to collect acoustic data for different protocols.For each protocol,starting far from LBO,we gradually move towards the LBO regime,capturing a quasi-static time series dataset at different conditions.Using one of the protocols in our dataset as the reference protocol,we find a transition state metric for our trained deep learning model to detect the imminent LBO in other test protocols.We find that our proposed approach is more precise and computationally faster than other baseline models to detect the transition to LBO.Therefore,we endorse this technique for monitoring the operation of lean combustion engines in real time.

深水油气开采安全风险评估与管控研究进展

深水油气领域是未来中国能源发展的主战场,加大深水油气勘探开发力度是建设海洋强国和保障国家能源安全的有效途径,但严苛复杂的海洋环境和工艺条件是深水油气开发必须面对的现实挑战。为此针对深水油气开采的主要作业场景,系统开展钻井和生产过程中井喷、泄漏、燃爆等重大事故的风险评估、风险演化、后果评估及事故防控研究,定量评估深水钻井作业及井控工艺过程风险,提出钻井作业事故连锁风险演化方法,建立钻井及井控作业关键屏障可靠性评估模型,同时针对深水油气开采工艺事故风险,基于机器学习算法和数据驱动模型,形成考虑多场景、多参数的普适性事故风险评价方法和数字化防控体系。可为深水油气开采工程风险评估和防控提供良好的理论基础和技术支撑。

井喷失控喷流运动学特征参数确定方法

井喷失控是石油及天然气开发中出现的重大恶性事故 ,它将严重危及人民的生命财产 ,污染良田 ,破坏生态环境 ,造成地下资源损失。文章利用空气中紊动射流理论 ,视失控井喷流为一束沉没自由紊动射流 ,分析喷流形状特征尺寸和速度场分布及参数的确定方法 ,为失控井喷着火井处理方案分析 ,处理设计及处理作业提供基础数据 ,达到快速清障、灭火、重建井口控制系统。