BH-N型不提钻换钻头钻进技术研究与应用

地质钻探施工时起下钻更换钻头,需要占用大量时间,且存在一定的安全隐患,大大影响钻探效率,采用不提钻换钻头钻进技术可以很好的解决这个问题。以N规格绳索取心钻杆为使用平台,沿用BH-75钻具基本结构,并针对其存在问题,研制BH-N规格的不提钻换钻头钻具,同时根据N规格钻具的具体结构完善BH-75钻具,提高了钻具的承压能力和钻具收敛(投送)稳定性,增设了自动除沙机构等。在山东乳山金青顶金矿ZK43-1钻孔进行了现场应用,在孔深2081.20~2211.40米实现了不提钻换钻头,钻具岩心采取率达到100%,岩心质量好,最大限度减少起下钻次数,有效预防起下钻引发孔内事故。不提钻换钻头钻进技术为深孔地质勘探中钻进强研磨性、打滑、软硬频繁交替等地层,提供了及时优化钻头使用方案,降低能源消耗,有效的保护孔壁安全和减少劳动强度。

BH复杂断块油田水平地应力的测井计算方法

地应力的大小和方向对油气田勘探开发工程有重要意义,其中水平地应力的精准计算是关键。BH油田断裂构造发育,地应力状态复杂多变,常用的水平地应力计算模型适应性较差。充分考虑BH油田复杂断块特征,结合岩石力学-地应力同步联测实验结果,分析了断层各要素对水平地应力的影响程度,由此建立了断层对水平两向地应力大小的影响因子K_(H)和K_(h)估算方法,在此基础上改进得到了适用于复杂断块构造的水平地应力计算模型:BH模型。利用此模型和测井资料可实现连续准确地计算工区不同层位的水平地应力,其地应力计算精度不但优于传统模型,而且能够很好地满足钻井和压裂等工程需求。

简易BH3分析法在血液肿瘤药敏筛选的初步探索

目的建立一种血液肿瘤BCL-2抗凋亡蛋白抑制剂药敏筛选的简易BH3分析法。方法建立基于显微镜和JC-1染色的BH3分析方法,通过BH3-only模拟肽描绘K562、NB4细胞系BCL-2家族抗凋亡蛋白依赖谱,应用聚合酶链式反应(polymerase chain reaction,PCR)加以验证;回溯临床治疗疗效,检验该方法对临床样本BH3药敏分析结果的符合情况。结果BH3分析结果显示NB4对抗凋亡蛋白的依赖程度依次为BCL2>MC1-1>BCL-XL;K562的依赖程度依次为BCL-XL>MC1-1>BCL2。PCR分析BCL-2家族基因表达量显示,K562抗凋亡蛋白MCL-1、BCL2、BCL-XL相对表达程度较高,BH3-only促凋亡蛋白中BIM、PUMA、NOXA高表达而HRK低表达,细胞抗凋亡能力更依赖于BCL-XL;NB4抗凋亡蛋白BCL-XL表达明显低于MCL-1与BCL-2,BH3-only促凋亡蛋白NOXA低表达,细胞抗凋亡更依赖于MCL-1与BCL-2而非BCL-XL,与BH3分析结果相符。对连续6例血液肿瘤患者骨髓进行BH3分析,结果显示6例患者均对HRK(BCL-XL抑制物)、VEN(BCL-2抑制物)不敏感;4例患者(例1~3,例5)对NOXA(MCL-1抑制物)表现为敏感,2例(例4、例6)的敏感度较低(<50%)。药敏预测结果显示6例患者均对BCL-2抑制剂耐药,例1~3、例5患者对MCL1抑制剂敏感,例4和例6对MCL1抑制剂可能耐药。回溯临床用药效果(4~6个疗程)显示例1~5患者对BCL-2抑制剂相关方案治疗无效,考虑与BCL-2抑制剂不敏感有关,例5更换西达苯胺治疗有效,例4和例6患者西达苯胺相关方案疗效不佳,考虑与MCL-1抑制物不敏感有关,上述临床结局与BH3预测结果一致。结论基于荧光显微镜和JC-1染色的BH3分析是简便可行的,可用于检测血液肿瘤细胞对不同抗凋亡蛋白的依赖性,从而为BCL-2家族相关抑制剂的选择提供证据。

Complication rates after direct anterior vs posterior approach for hip hemiarthroplasty in elderly individuals with femoral neck fractures

BACKGROUND Dislocation rates after hemiarthroplasty reportedly vary from 1%to 17%.This serious complication is associated with increased morbidity and mortality rates.Approaches to this surgery are still debated,with no consensus regarding the superiority of any single approach.AIM To compare early postoperative complications after implementing the direct anterior and posterior approaches(PL)for hip hemiarthroplasty after femoral neck fractures.METHODS This is a comparative,retrospective,single-center cohort study conducted at a university hospital.Between March 2008 and December 2018,273 patients(a total of 280 hips)underwent bipolar hemiarthroplasties(n=280)for displaced femoral neck fractures using either the PL(n=171)or the minimally invasive direct anterior approach(DAA)(n=109).The choice of approach was related to the surgeons’practices;the implant types were similar and unrelated to the approach.Dislocation rates and other complications were reviewed after a minimum followup of 6 mo.RESULTS Both treatment groups had similarly aged patients(mean age:82 years),sex ratios,patient body mass indexes,and patient comorbidities.Surgical data(surgery delay time,operative time,and blood loss volume)did not differ significantly between the groups.The 30 d mortality rate was higher in the PL group(9.9%)than in the DAA group(3.7%),but the difference was not statistically significant(P=0.052).Among the one-month survivors,a significantly higher rate of dislocation was observed in the PL group(14/154;9.1%)than in the DAA group(0/105;0%)(P=0.002).Of the 14 patients with dislocation,8 underwent revision surgery for recurrent instability(posterior group),and one of them had 2 additional procedures due to a deep infection.The rate of other complications(e.g.,perioperative and early postoperative periprosthetic fractures and infection-related complications)did not differ significantly between the groups.CONCLUSION These findings suggest that the DAA to bipolar hemiarthroplasty for patients with femoral neck fractures is associated with a lower dislocation rate(<1%)than the PL.

长时效期BH钢的烘烤硬化性能及其机理研究

采用万能材料试验机、TEM/EDS、3DAP,分别对时效3个月和6个月的超低碳烘烤硬化钢(钢号HC180B)进行力学性能测试和组织、析出相表征,并分析了烘烤硬化过程中的元素偏聚行为。结果表明,与时效3个月相比,钢板在时效6个月后仍具有优异的力学性能,展示出良好的抗时效性。TEM和3DAP分析显示,退火冷轧板中仅有C原子在晶界处轻微偏聚,B、Mn、Nb、Ti均匀分布在钢中;2%预拉伸变形后,这些元素在相同晶界处表现出不同程度的偏聚现象,TiN多呈矩形优先在晶界大量析出,NbC则少量析出;进一步烘烤后,C、B、Mn、Nb、Ti在晶界处的偏聚现象更为显著且连续,NbC呈椭球形大量析出。析出相与位错、晶界的交互作用显著提升了钢板的烘烤硬化性能。

Exploring an eco-friendly approach to improve soil tensile behavior and cracking resistance

Soil tensile strength is a critical parameter governing the initiation and propagation of tensile cracking.This study proposes an eco-friendly approach to improve the tensile behavior and crack resistance of clayey soils.To validate the feasibility and efficacy of the proposed approach,direct tensile tests were employed to determine the tensile strength of the compacted soil with different W-OH treatment concentrations and water contents.Desiccation tests were also performed to evaluate the effectiveness of W-OH treatment in enhancing soil tensile cracking resistance.During this period,the effects of W-OH treatment concentration and water content on tensile properties,soil suction and microstructure were investigated.The tensile tests reveal that W-OH treatment has a significant impact on the tensile strength and failure mode of the soil,which not only effectively enhances the tensile strength and failure displacement,but also changes the brittle failure behavior into a more ductile quasi-brittle failure behavior.The suction measurements and mercury intrusion porosimetry(MIP)tests show that W-OH treatment can slightly reduce soil suction by affecting skeleton structure and increasing macropores.Combined with the microstructural analysis,it becomes evident that the significant improvement in soil tensile behavior through W-OH treatment is mainly attributed to the W-OH gel's ability to provide additional binding force for bridging and encapsulating the soil particles.Moreover,desiccation tests demonstrate that W-OH treatment can significantly reduce or even inhibit the formation of soil tensile cracking.With the increase of W-OH treatment concentration,the surface crack ratio and total crack length are significantly reduced.This study enhances a fundamental understanding of eco-polymer impacts on soil mechanical properties and provides valuable insight into their potential application for improving soil crack resistance.

Laparoscopic left hemihepatectomy guided by indocyanine green fluorescence: A cranial-dorsal approach

BACKGROUND Advancements in laparoscopic technology and a deeper understanding of intra-hepatic anatomy have led to the establishment of more precise laparoscopic hepatectomy(LH)techniques.The indocyanine green(ICG)fluorescence navi-gation technique has emerged as the most effective method for identifying hepatic regions,potentially overcoming the limitations of LH.While laparoscopic left hemihepatectomy(LLH)is a standardized procedure,there is a need for innova-tive strategies to enhance its outcomes.important anatomical markers,surgical skills,and ICG staining methods.METHODS Thirty-seven patients who underwent ICG fluorescence-guided LLH at Qujing Second People's Hospital between January 2019 and February 2022 were retrospectively analyzed.The cranial-dorsal approach was performed which involves dissecting the left hepatic vein cephalad,isolating the Arantius ligament,exposing the middle hepatic vein,and dissecting the parenchyma from the dorsal to the foot in order to complete the anatomical LLH.The surgical methods,as well as intra-and post-surgical data,were recorded and analyzed.Our hospital’s Medical Ethics Committee approved this study(Ethical review:2022-019-01).RESULTS Intraoperative blood loss during LLH was 335.68±99.869 mL and the rates of transfusion and conversion to laparotomy were 13.5%and 0%,respectively.The overall incidence of complications throughout the follow-up(median of 18 months;range 1-36 months)was 21.6%.No mortality or severe complications(level IV)were reported.CONCLUSION LLH has the potential to become a novel,standardized approach that can effectively,safely,and simply expose the middle hepatic vein and meet the requirements of precision surgery.

Which approach of total hip arthroplasty is the best efficacy and least complication?

BACKGROUND Total hip arthroplasty is as an effective intervention to relieve pain and improve hip function.Approaches of the hip have been exhaustively explored about pros and cons.The efficacy and the complications of hip approaches remains inconclusive.This study conducted an umbrella review to systematically appraise previous meta-analysis(MAs)including conventional posterior approach(PA),and minimally invasive surgeries as the lateral approach(LA),direct anterior approach(DAA),2-incisions method,mini-lateral approach and the newest technique direct superior approach(DSA)or supercapsular percutaneouslyassisted total hip(SuperPath).AIM To compare the efficacy and complications of hip approaches that have been published in all MAs and randomized controlled trials(RCTs).METHODS MAs were identified from MEDLINE and Scopus from inception until 2023.RCTs were then updated from the latest MA to September 2023.This study included studies which compared hip approaches and reported at least one outcome such as Harris Hip Score(HHS),dislocation,intra-operative fracture,wound compliData were independently selected,extracted and assessed by two reviewers.Network MA and cluster rank and surface under the cumulative ranking curve(SUCRA)were estimated for treatment efficacy and safety.RESULTS Finally,twenty-eight MAs(40 RCTs),and 13 RCTs were retrieved.In total 47 RCTs were included for reanalysis.The results of corrected covered area showed high degree(13.80%).Among 47 RCTs,most of the studies were low risk of bias in part of random process and outcome reporting,while other domains were medium to high risk of bias.DAA significantly provided higher HHS at three months than PA[pooled unstandardized mean difference(USMD):3.49,95%confidence interval(CI):0.98,6.00 with SUCRA:85.9],followed by DSA/SuperPath(USMD:1.57,95%CI:-1.55,4.69 with SUCRA:57.6).All approaches had indifferent dislocation and intraoperative fracture rates.SUCRA comparing early functional outcome and composite complications(dislocation,intra-operative fracture,wound complication,and nerve injury)found DAA was the best approach followed by DSA/SuperPath.CONCLUSION DSA/SuperPath had better earlier functional outcome than PA,but still could not overcome the result of DAA.This technique might be the other preferred option with acceptable complications.

Minimalistic approach to left atrial appendage occlusion guided by cardiac computed tomography angiography

OBJECTIVE To assess the feasibility and safety of the minimalistic approach to left atrial appendage occlusion(LAAO) guided by cardiac computed tomography angiography(CCTA).METHODS Ninety consecutive patients who underwent LAAO, with or without CCTA-guided, were matched(1:2). Each step of the LAAO procedure in the computed tomography(CT) guidance group(CT group) was directed by preprocedural CT planning. In the control group, LAAO was performed using the standard method. All patients were followed up for 12 months, and device surveillance was conducted using CCTA.RESULTS A total of 90 patients were included in the analysis, with 30 patients in the CT group and 60 matched patients in the control group. All patients were successfully implanted with Watchman devices. The mean ages for the CT group and the control group were 70.0 ± 9.4 years and 68.4 ± 11.9 years(P = 0.52), respectively. The procedure duration(45.6 ± 10.7 min vs. 58.8 ± 13.0 min,P < 0.001) and hospital stay(7.5 ± 2.4 day vs. 9.6 ± 2.8 day, P = 0.001) in the CT group was significantly shorter compared to the control group. However, the total radiation dose was higher in the CT group compared to the control group(904.9 ± 348.0 m Gy vs.711.9 ± 211.2 m Gy, P = 0.002). There were no significant differences in periprocedural pericardial effusion(3.3% vs. 6.3%, P = 0.8) between the two groups. The rate of postprocedural adverse events(13.3% vs. 18.3%, P = 0.55) were comparable between both groups at 12 months follow-up.CONCLUSIONS CCTA is capable of detailed LAAO procedure planning. Minimalistic LAAO with preprocedural CCTA planning was feasible and safe, with shortened procedure time and acceptable increased radiation and contras consumption. For patients with contraindications to general anesthesia and/or transesophageal echocardiography, this promising method may be an alternative to conventional LAAO.

Virtual source approach for maximizing resolution in high-penetration gamma-ray imaging

High-energy gamma-ray radiography has exceptional penetration ability and has become an indispensable nondestructive testing(NDT)tool in various fields.For high-energy photons,point projection radiography is almost the only feasible imaging method,and its spatial resolution is primarily constrained by the size of the gamma-ray source.In conventional industrial applications,gamma-ray sources are commonly based on electron beams driven by accelerators,utilizing the process of bremsstrahlung radiation.The size of the gamma-ray source is dependent on the dimensional characteristics of the electron beam.Extensive research has been conducted on various advanced accelerator technologies that have the potential to greatly improve spatial resolution in NDT.In our investigation of laser-driven gamma-ray sources,a spatial resolution of about 90μm is achieved when the areal density of the penetrated object is 120 g/cm^(2).A virtual source approach is proposed to optimize the size of the gamma-ray source used for imaging,with the aim of maximizing spatial resolution.In this virtual source approach,the gamma ray can be considered as being emitted from a virtual source within the convertor,where the equivalent gamma-ray source size in imaging is much smaller than the actual emission area.On the basis of Monte Carlo simulations,we derive a set of evaluation formulas for virtual source scale and gamma-ray emission angle.Under optimal conditions,the virtual source size can be as small as 15μm,which can significantly improve the spatial resolution of high-penetration imaging to less than 50μm.

Debate on direct-anterior vs posterior approach for hip hemiarthroplasty:The authors’insights

We read and discussed the study entitled“Complication rates after direct anterior vs posterior approach for Hip Hemiarthroplasty in elderly individuals with femoral neck fractures”with great interest.The authors have done justice to the topic of comparison of anterior and posterior surgical approaches for bipolar hemiarthroplasty which has been an everlasting debate in the existing literature.However,there are certain aspects of this study that need clarification from the authors.

Direct anterior compared to posterior approach for hip hemiarthroplasty following femoral neck fractures

The differences in complication rates between the direct anterior and posterior approaches for hemiarthroplasty in elderly patients with femoral neck fractures are not yet fully understood.Dislocation,a severe complication associated with increased mortality and often requiring additional surgery,may occur less frequently with the direct anterior approach compared to the posterior approach.Careful consideration of patient demographics is essential when planning the surgical approach.Future research in this area should focus on robust randomized controlled trials involving elderly patients recovering from femoral neck fractures.

A FLEXIBLE OBJECTIVE-CONSTRAINT APPROACH AND A NEW ALGORITHM FOR CONSTRUCTING THE PARETO FRONT OF MULTIOBJECTIVE OPTIMIZATION PROBLEMS

In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programming problem. The presented scalarized problem extends the objective-constraint problem. It is demonstrated that how adding variables to the scalarized problem, can lead to find conditions for (weakly, properly) Pareto optimal solutions. Applying the obtained necessary and sufficient conditions, two algorithms for generating the Pareto front approximation of bi-objective and three-objective programming problems are designed. These algorithms are easy to implement and can achieve an even approximation of (weakly, properly) Pareto optimal solutions. These algorithms can be generalized for optimization problems with more than three criterion functions, too. The effectiveness and capability of the algorithms are demonstrated in test problems.

A Deep Learning Based Broadcast Approach for Image Semantic Communication over Fading Channels

We consider an image semantic communication system in a time-varying fading Gaussian MIMO channel,with a finite number of channel states.A deep learning-aided broadcast approach scheme is proposed to benefit the adaptive semantic transmission in terms of different channel states.We combine the classic broadcast approach with the image transformer to implement this adaptive joint source and channel coding(JSCC)scheme.Specifically,we utilize the neural network(NN)to jointly optimize the hierarchical image compression and superposition code mapping within this scheme.The learned transformers and codebooks allow recovering of the image with an adaptive quality and low error rate at the receiver side,in each channel state.The simulation results exhibit our proposed scheme can dynamically adapt the coding to the current channel state and outperform some existing intelligent schemes with the fixed coding block.

Lychrel Numbers in Base 10: A Probabilistic Approach

For decades, Lychrel numbers have been studied on many bases. Their existence has been proven in base 2, 11 or 17. This paper presents a probabilistic proof of the existence of Lychrel number in base 10 and provides some properties which enable a mathematical extraction of new Lychrel numbers from existing ones. This probabilistic approach has the advantage of being extendable to other bases. The results show that palindromes can also be Lychrel numbers.

Probabilistic Analysis of Slope Using Finite Element Approach and Limit Equilibrium Approach around Amalpata Landslide of West Central, Nepal

The stability study of the ongoing and recurring Amalpata landslide in Baglung in Nepal’s Gandaki Province is presented in this research. The impacted slope is around 200 meters high, with two terraces that have different slope inclinations. The lower bench, located above the basement, consistently fails and sets others up for failure. The fluctuating water level of the slope, which travels down the slope masses, exacerbates the slide problem. The majority of these rocks are Amalpata landslide area experiences several structural disruptions. The area’s stability must be evaluated in order to prevent and control more harm from occurring to the nearby agricultural land and people living along the slope. The slopes’ failures increase the damages of house existing in nearby area and the erosion of the slope. Two modeling techniques the finite element approach and the limit equilibrium method were used to simulate the slope. The findings show that, in every case, the terrace above the basement is where the majority of the stress is concentrated, with a safety factor of near unity. Using probabilistic slope stability analysis, the failure probability was predicted to be between 98.90% and 100%.

“Instruction-Category” Approach of Test Suite Construction for Oven Embedded System

Being different from testing for popular GUI software, the “instruction-category” approach is proposed for testing embedded system. This approach is constructed by three steps including refining items, drawing instruction-brief and instruction-category, and constructing test suite. Consequently, this approach is adopted to test oven embedded system, and detail process is deeply discussed. As a result, the factual result indicates that the “instruction-category” approach can be effectively applied in embedded system testing as a black-box method for conformity testing.

Safety and efficacy of posterior approach for resection of spinal meningioma:Impact of dural attachment location

BACKGROUND Spinal meningiomas(SMs)are common benign tumors that are typically treated with surgical resection.The choice of surgical approach may vary depending on the location of dural attachment of the SM,with a posterior approach being the traditional preference.However,there is limited research available on the impact of dural attachment location on outcomes following posterior approach for SM resection.The average age of the included 34 patients’(10 males and 24 females)age was 62.09 years.Mean follow-up duration was 22.65 months.The location of SM was the thoracic spine in 32 cases,with only 2 in the cervical spine.On average,intraoperative blood loss was 520.59 mL,and operating time was 176.76 minutes.Thirty three cases had successful outcomes while only 1 experienced an unexpe-cted outcome.The tumor recurrence rate was 2.9%.After surgery,there were 3 cases of cerebral spinal fluid leakage,1 case of pneumonia,and 1 case of urinary tract infection.Dural attachments were predominantly found dorsal or dorso-lateral(13 cases),followed by ventral or ventrolateral(14 cases),and lateral(7 cases).The outcomes among these subgroups were similar.CONCLUSION The posterior approach for SM resection is safe and effective,yielding comparable surgical and neurological outcomes regardless of the dural attachment location.

Optimizing PID controller parameters for robust automatic voltage regulator system through indirect design approach-2

Automatic voltage regulators(AVR)are designed to manipulate a synchronous generator’s voltage level automatically.Proportional integral derivative(PID)controllers are typically used in AVR systems to regulate voltage.Although advanced PID tuning methods have been proposed,the actual voltage response differs from the theoretical predictions due to modeling errors and system uncertainties.This requires continuous fine tuning of the PID parameters.However,manual adjustment of these parameters can compromise the stability and robustness of the AVR system.This study focuses on the online self-tuning of PID controllers called indirect design approach-2(IDA-2)in AVR systems while preserving robustness.In particular,we indirectly tune the PID controller by shifting the frequency response.The new PID parameters depend on the frequency-shifting constant and the previously optimized PID parameters.Adjusting the frequency-shifting constant modifies all the PID parameters simultaneously,thereby improving the control performance and robustness.We evaluate the robustness of the proposed online PID tuning method by comparing the gain margins(GMs)and phase margins(PMs)with previously optimized PID parameters during parameter uncertainties.The proposed method is further evaluated in terms of disturbance rejection,measurement noise,and frequency response analysis during parameter uncertainty calculations against existing methods.Simulations show that the proposed method significantly improves the robustness of the controller in the AVR system.In summary,online self-tuning enables automated PID parameter adjustment in an AVR system,while maintaining stability and robustness.

Watson-Jones Anatomical Approach for Open Reduction and Internal Fixation of Proximal Femoral Fractures without Image Intensifier in a Low-Resource Setting

Introduction: Standard procedures for surgical fixation of proximal femoral fractures (PFF) require an image intensifier which in developing countries remains a luxury. We hypothesized that, with a well-codified technique, the Watson Jones approach (WJA) without image intensifier nor traction table, can allow open reduction and internal fixation (ORIF) of PFF using Dynamic hip screw (DHS), with satisfactory outcome. Patients and methods: Forty one consecutive patients (mean age 59.5 ± 21.6 years, 61% males) who were followed in a Teaching Hospital for PFF treated by ORIF using the WJA and DHS from January 2016 to December 2020 were reassessed. The outcome measures were the quality of the reduction, the positioning of the implants, the tip-apex distance (TAD), the rate and delay of consolidation, the functional results using Postel Merle d’Aubigné (PMA) score, the rate of surgical site infection (SSI) and the overall mortality. Logistic regression was used to determine factors associated with mechanical failure. Results: The mean follow-up period was 33.8 ± 15.0 months. Fracture reduction was good in 31 (75.6%) cases and acceptable in 8(19.5%) cases. Implant position was fair to good in 37 (90.2%) patients. The mean TAD was 26.1 ± 3.9 mm. Three patients developed SSI. Consolidation was achieved in 38 (92.6%) patients. The functional results were good to excellent in 80.5% of patients. The overall mortality rate was 7.3%. There were an association between mechanical failure and osteoporosis (p = 0.04), fracture reduction (p = 0.003), and TAD (p = 0.025). In multivariate logistic regression, no independent factors were predictive of mechanical failure. Conclusion: This study shows that ORIF using DHS for PFF via the Watson-Jones approach without an image intensifier can give satisfactory anatomical and functional outcomes in low-resource settings. It provides and validates a reliable and reproducible technique that deserves to be diffused to surgeons in austere areas over the world.