Open Hole Research Articles

Anxiolytic Effect of Sesamol, Possibly Through the GABAkine Interaction Pathway.

Plant-based components have helped generate novel lead molecules and scaffolds for anxiety research in psychopharmacology. The present study examined the anxiolytic properties of sesamol (SES), a phenolic lignan derived from Sesamum indicum, employing both in vivo and computational methods to understand its mechanisms of action. In this experiment, adult Swiss albino mice received various doses of SES (25 and 50 mg/kg, p.o.) orally. Afterward, a series of behavioral assessments, including open field, swing, hole cross, and light-dark testing, were conducted. The impact of the GABAergic agonist diazepam (DZP-1 mg/kg, i.p.) along with the antagonist flumazenil (FLU-0.1 mg/kg, i.p.) has been studied as provided concurrently with the SES-50 group. Computational studies were performed to comprehend the interaction between SES and GABAA receptor subunits (α2 and α3). The results of our investigation revealed that SES dose-dependently and significantly (p < 0.05) reduced the number of square crosses, hole crosses, swings, grooming, and rearing along with a reduction of light residence time in animals. When combined with DZP, SES-50 significantly reduced all these parameters, while altering with FLU-0.1. The molecular docking analysis showed that the SES has a relatively good binding score (-5.03 ± 0.15 and -5.25 ± 0.23 kcal/mol) with GABAA receptor α2 and α3 subunits, respectively. The SES triggers anxiolytic effects via GABAA receptor α2 and α3 subunit interactions. Furthermore, precise and comprehensive preclinical research must be considered to validate potential SES targets for anxiolytic impact, clinical trial efficacy, and safety.

Micromechanical study of core barrel drilling for rotary drilling rigs based on the discrete element method

Abstract This study developed a gravel soil granular bed model using the discrete element method, elaborating on the core barrel drilling process by integrating bond-breaking and particle flow patterns. A quantitative description of the drilling process is achieved by defining bond-breaking efficiency. The results indicate that the force on particles near the drill tooth is the greatest, and this force increases with the core barrel feed rate, which enhances drilling efficiency and exacerbates wear on the drill tooth and guide bars. An increase in rotational speed raises the force on the particles in the boundary region, leading to deeper wear of the guide bar; however, the enlargement of particle voids near the drill tooth mitigates wear. Additionally, a coupled discrete element method and finite element method are developed to analyse the effects of drilling parameters on drill tooth deformation, revealing that the design of the open hole at the top of the drill can effectively reduce the maximum equivalent stress and wear depth. The conclusions drawn contribute to understanding particle mechanics, the particle bonding damage mechanism, and drilling mechanical behavior, providing a reference for optimizing drilling operations and drill design.

Experimental and numerical studies of the open hole tensile strength of drilled‐ and molded‐hole unidirectional laminates

AbstractIn this paper, we created a new molded‐hole process to manufacture holes instead of drilling in unidirectional (UD) carbon fiber reinforced plastics avoid fiber discontinuity. Several open hole tensile (OHT) tests were carried out on specimens with Cross ply (CP) and Quasi‐isotropic (QI) stacking sequence with drilled holes and molded holes. At the same time, we established finite element analysis (FEA) models of drilled‐hole laminate and molded‐hole laminate to characterize the stress field around the hole. The numerical analysis results reveals that the max principal strain distribution around the molded hole has much higher coincidence with fiber axial direction than that in drilled‐hole laminate. Moreover, the OHT strength results of QI specimens indicate that the plates with molded holes were more 50% higher than those with drilled holes. This process will provide reference for molded UD CFRP structure holes. And the numerical model can help engineering designer make OHT strength prediction.Highlights A new molded‐hole process for unidirectional prepreg was created. Molded‐hole specimens have higher open hole tensile strength than drilled‐hole pieces. The simulation results were close to the experimental results.

TECHNICAL SOLUTIONS FOR DRILLING WELLS IN CHALLENGING CONDITIONS

Abstract. Drilling modern wells in difficult mining and geological conditions poses a number of tasks for engineers that require special solutions. These include instability of borehole walls in difficult geomechanical conditions, drilling of directional wells with long horizontal boreholes and their completion by multi-stage hydraulic fracturing, drilling in conditions of a narrow «window» of drilling mud density, as well as drilling of wells with extended reach from the vertical. The article describes the main difficulties and problems encountered in solving these problems, such as: wellbore collapse, absorption during drilling in difficult geomechanical conditions, the impossibility of running casing strings and liners into wells with a large deviation from the vertical by traditional methods, difficulties in cementing long horizontal liners, running completion for multi-stage hydraulic fracturing of a formation with packers in an open hole, difficulties in drilling in conditions of insignificant difference in pore pressure gradients and hydraulic fracturing. Certain proven solutions are offered to overcome such problems and difficulties, examples of solutions to the described problems are given. Among these solutions are geomechanical modeling with subsequent calculation of wellbore stability, as well as optimization of well trajectories, the product of multi-stage hydraulic fracturing by the Plug &amp; Perf method of isolation and perforation in order to achieve a larger number of stages, as well as solutions for improving the quality of cementing horizontal liners. Pressure-controlled drilling technology and flotation of casing and liners into ERD wells will be considered. It concludes with conclusions about the relevance of the solutions described, the possibility of combining them to increase efficiency or under complex conditions, as well as aspects that require attention when choosing technologies and their implementation, such as the importance of risk assessment and the importance of technical integration of technologies, as well as preliminary calculations and analysis of technology implementation experience.

Intelligent optimization of horizontal wellbore trajectory based on reinforcement learning

Ultra-long horizontal wells are crucial for improving the production and developmental benefits of shale oil and gas wells. Currently, advanced downhole semi-closed-loop steering drilling technology depends on a dual communication mechanism between the surface and downhole, as well as the empirical decisions of human experts. However, it is difficult to acutely control the trajectory of ultra-long horizontal open hole drilling in a reservoir owing to geological uncertainties related to shale oil and gas, the uncertainty of the drilling tool's building capacity, and the lag of measurement information while drilling. This report proposes an adaptive target detection and design method for ultra-long horizontal well trajectories based on reinforcement learning. The developed approach enables dynamic identification of reservoir sequences according to logging-while-drilling data and prediction of horizontal targets in real-time, with a recognition accuracy of 90.1%. Additionally, measurement-while-drilling data are used to accurately characterize the depth, inclination, and azimuth of the target-entering process. The dynamic interaction mechanism between the bit and the target environment is simulated by defining the bit action, reward function, and an update mechanism. The drilling engineering conditions restrict the interactions, such that the bit automatically decides the direction in which to drill the targets, demonstrating 100% accuracy for the wellbore trajectory toward the target. The experimental application results indicate that the developed method can be applied to determine the dynamic target area of a horizontal well in real time and make intelligent downhole decisions regarding ultra-long horizontal section borehole trajectory adjustments while drilling and measuring. The drilling rate of high-quality reservoirs is therefore significantly improved. The results discussed herein provide insights to support further developments of downhole full-closed-loop intelligent autonomous decision-making borehole trajectory control.

Mechanical properties of open‐hole unidirectional laminates: Hybridization of jute unidirectional fabrics with glass fabrics

AbstractThis study examines the mechanical properties of open‐hole unidirectional laminates by hybridizing jute and glass fabrics. Characterization involved microscopy, thickness variation, density measurements, tensile, and flexural tests. Numerical models were developed for each configuration, validated by experimental data, with a VUMAT subroutine implemented in ABAQUS/Explicit™ to simulate progressive damage using the 3D Hashin criteria. Results showed voids in the interphase regions of both jute‐based and hybrid laminates, indicating that jute fibers contribute to void formation. Thickness varied with the number of hybrid interfaces, with the glass laminate (G5) being thinnest, while jute and hybrid laminates (JGJGJ, JGGGJ and J5) were thicker. Density variation was influenced by the fiber types and their respective densities. Tensile tests revealed lower strength and modulus in jute laminates compared to glass. Open holes reduced tensile properties across laminates, except for G5. Numerical‐experimental tensile strength differences ranged from 0.5% to 6.1% (without hole) and 3.7% to 64.0% (with hole). Open‐hole laminates also showed reduced flexural strength but maintained a consistent flexural modulus. Numerical and experimental results for jute and hybrid laminates matched closely, with differences from 0.02% to 19.5%. Failure modes during tensile and flexural tests provided important insights into laminate behavior.Highlights Hybridization of jute and glass fibers led to void formation in interphase regions. Thickness variation in laminates influenced by the number of hybrid interfaces. Density variation primarily influenced by fiber types and their densities. Bi‐component jute laminates showed lower tensile properties compared to glass laminates. Open holes resulted in decreased tensile properties, except for G5‐H laminate. Failure modes during tensile testing provided valuable insights into laminate behavior. Open‐hole laminates exhibited reduced flexural strength with similar flexural modulus.

Comparison of diagnostic yields, operative times, and post-operative hemorrhage between twist drill versus burr hole craniotomy approaches for stereotactic needle brain biopsy.

Stereotactic frameless needle brain biopsy is a common neurosurgical procedure performed via twist drill or open burr hole approaches. We aim to compare diagnostic yields and surgical outcomes to delineate the safety and efficacy of both approaches. A retrospective database of all stereotactic needle biopsy procedures performed at a single institution over 30 months was conglomerated. Demographics, medical comorbidities, operative details/complications, immediate post-operative imaging, and pathology were abstracted. Two hundred and twenty-five needle biopsies were identified, of which 165 (73.3%) were open, and 60 (26.7%) were twist drill. Diagnostic pathology yield rates between open (84.8%) and twist drill (93.3%) approaches were similar (p = 0.15), with a median of 4 cores taken in each (p = 0.30). Diagnostic tissue yields with an intra-operative pause for pathology confirmation was 90.4% compared to 79.1% without pause (p = 0.036, OR 2.49). Median operative times for open versus twist drill procedures were 68.0min (IQR 49-83) versus 35.5min (IQR 26-54), respectively (Wilcoxon p < 0.001), which remained significant after controlling for awaiting intraoperative pathology using bivariable linear modeling (p < 0.001). Intraoperative bleeding through the needle cannula was noted in 22 patients (9.8%), including eight twist drill (13.3%) and 14 open needles (8.5%). Of 197 cases (87.6%) with post-operative cranial imaging (CT/MRI), 90 (45.7%) demonstrated some degree of post-operative hemorrhage characterized as superficial (n = 10, 11.1%), deep/intralesional (n = 64, 71.1%) bleeding, or both (n = 16, 17.9%). Bleeding rates between open (46.7%) and twist drill (43.3%) approaches were similar (p = 0.78). Post-operative clinical decline or neurological change was noted in 9 patients (4.0%), including one twist drill (1.7%) and eight open needles (4.8%), among which 7 (78%) had deep blood products identified on post-operative imaging. Stereotactic needle biopsy via twist drill approach has similar diagnostic yield rates, asymptomatic bleeding rates, and post-operative complications with significantly shorter operative time and smaller incision size than conventional open burr hole needle biopsy. Using intra-operative frozen histopathology for presumed sufficient diagnostic tissue may improve final pathologic diagnostic rates regardless of approach technique.

Soil Physical Properties, Root Distribution, and “Ponkan” Tangerine Yield Across Different Rootstocks in a Deep Tillage Ultisol

Deep soil tillage and proper rootstock selection mitigate the root development limitations in Ultisol’s Bt horizon, enhancing the citrus yield potential. This study evaluates the root spatial distribution of three Ponkan tangerine rootstocks in Ultisol under deep tillage alongside the physical-hydric attributes and plant measurements. The experimental area underwent furrow creation, subsoiling, and hole opening for planting. The treatments included three rootstocks: “Cravo Santa Cruz” (CSC), “Sunki Tropical” (ST), and “Citrandarin Índio” (CI). Under the Ultisol preparation, these rootstocks were compared to a native forest area (FA). Three years post-initial tillage, soil samples were collected at depths of 0–0.05, 0.35–0.40, and 0.45–0.50 m from the pre-established positions. The evaluation encompassed soil dispersive clay, available water, crop water use, plant measurement, and crop yield. The root evaluation utilized the crop profile method and 2D images, with subsequent surface mapping of the root variables, number (NR), and diameter (RD) analyzed via kriging geostatistical analysis. The Ultisol showed significant changes in its physical-hydric attributes regarding structural change and more excellent clay dispersion, with a considerable contribution to the micropore volume. Deep tillage effectively improved the root spatial distribution, especially concerning the number and diameter of roots, and enhanced the water use, reflected in the vegetative growth and yield, with the rootstock CSC standing out.

Multiscale study on the properties and crack propagation of 2D woven SiCf/SiC with pores using elastoplastic phase field

AbstractTo understand the effect of processing and prefabricated pores on 2D woven SiCf/SiC composites (2DW‐SiCf/SiC), their crack propagation and mechanical response under tension load at meso‐ and macro‐ scale are investigated by a promising elastoplastic phase field method (EPPFM). Of much interest, the computational results are well consistent with the available experimental results, verifying the reliability of EPPFM. A significant dependence on pores is observed in the relationship between the strength, Young's modulus, work of fracture of 2DW‐SiCf/SiC and porosity when pores exist solely in the matrix out of yarns, and both in the matrix and yarns, respectively. Moreover, the more dangerous processing pores at mesoscale near yarn are attributed to the inconsistent deformation of the yarn and matrix. Finally, the EPPFM is used for the effect of geometry size on the joint failure mode of 2DW‐SiCf/SiC plate with prefabricated open holes under pin‐loading. Of importance, the more safe bearing failure mode occurs in 2DW‐SiCf/SiC plate when edge distance‐to‐hole diameter ratio and width‐to‐hole diameter ratio are greater than 1.5 and 3, respectively.

Study on Mechanical Properties of Steel-Strengthened Bamboo Beams with Webbing Opening

Bamboo beams are often reinforced with built-in steel sections to enhance their strength and load-bearing capacity. In this paper, we studied the effect of different parameters, including the location of the hole, the hole size, and the thicknesses of the steel and bamboo, on the mechanical properties of reinforced beams. The damage patterns, deformation characteristics, and force-transfer mechanisms, as well as the mechanical properties of reinforced beams with different hole shapes, underwent non-linear finite element analysis. The damage sustained by the reinforced bamboo beam differed from that of the traditional bamboo beam; two diagonal points formed a plastic hinge, mainly during the process of shear damage to the hole. It was determined that the hole size and the thickness of the bamboo have the greatest influence on the mechanical properties of the reinforced beam. The damage characteristics of the composited beams with different holes are similar; the bearing capacity of reinforced beams with open square holes is reduced by 10%–25%compared with circular holes.

Progressive failure analysis of laminates with an open hole subjected to compressive loading (OHC) using the enhanced semi-discrete modeling framework

The Open-hole compressive (OHC) strength of a fiber reinforced laminate is one of the most critical allowables for design of aerostructures. In this paper, results for predicting the OHC strength using the semi-discrete damage modeling framework are presented. The predictions are seen to capture experimentally observed failure mechanisms and measured failure loads. The constitutive model includes local axial compressive failure (and subsequent load bearing at a reduced plateau stress) while maintaining numerical robustness. Standard stacking sequences (quasi-isotropic, “hard” and “soft”) have been analyzed and compared to publicly available databases. Additionally, the model is challenged to predict delamination-dominated failure due to ply-scaling. Overall, the model is able to capture relevant failure mechanisms, while the ultimate loads are predicted with good accuracy. Therefore, this framework can be used with confidence in predicting OHC strengths of laminates.

An experimental investigation of the impact of seawater on the compressive performance of solid and open hole glass/epoxy laminates

An experimental investigation of the impact of seawater on the compressive performance of solid and open hole glass/epoxy laminates

Discussion on the Technology of Leak Prevention and Sealing in Drilling Engineering

Abstract Lost circulation is one of the most serious and complex situations that affect the safety of drilling operations. The occurrence of lost circulation not only causes losses to drilling engineering, but also poses great difficulties for the exploration and development of oil and gas resources. Only by solving the problem of well leakage can drilling operations be carried out effectively and economically. Lost circulation can have a significant impact on exploration and development work. However, everything has two aspects. In the case of the same reservoir and leakage, once a well leakage is found, it indicates the appearance of an oil and gas reservoir, which is more common in fractured reservoirs. Therefore, in the expected drilling of reservoir sections, it is necessary to analyze and judge leaks well to avoid human error. Leakage can occur in shallow, medium, and deep layers, as well as in different geological epochs, such as from the Quaternary to the Paleozoic, and can occur in various rock formations. From the perspective of drilling, with long open holes, multiple pressure layers, and complex formations, especially when drilling adjustment wells, the problem of well leakage appears to be common and more serious, and the occurrence of well leakage will cause significant economic losses. So, we should prioritize prevention and try to avoid the occurrence of well leakage. If drilling is carried out in formations with well leakage, but appropriate drilling techniques and measures are taken, it is possible that well leakage will not occur, and at least the degree of leakage can be greatly reduced. In case of a well leakage, effective measures should be taken in a timely manner to block it and ensure the smooth progress of drilling. Therefore, the significance of researching leak prevention and plugging technology is significant.

Research and Application of Plugging Drilling and Completion Technology for Difficult Old Well in Changchun Gas Storage

Abstract Changchun Gas Storage has been included in the 14th Five-Year Plan for the development of petroleum and natural gas in Jilin Province. Its smooth construction and safe operation are crucial to ensure the stable supply of natural gas in Changchun. Well X106F located in the construction area was abandoned in 1988 due to drilling tool falling and multiple salvage failures. In order to ensure the sealing and integrity of the gas storage, it is necessary to effectively plug the drilling cover. In view of the problems of low well history accuracy, poor well wall stability and difficulty in cementing large boreholes, open hole drilling, trajectory design and control, film-forming and wall-fixing drilling fluid and prestressed cementing technologies are applied. By optimizing drilling tools, optimizing drilling parameters, designing the three-opening well structure and “five-section” profile, the plugging well construction requirements are met. The first and second open drilling along the old well borehole, 1313m deep on the first try to find top of the fish, after cementing plug, side tracking to 50m below the top of the fish and then cementing;for third spud control trajectory to accompanied the old well, according to the results of passive magnetic guidance, real-time adjustment of the trajectory scheme and construction plan, finally successfully collided with the old well at 1893m deep, after cementing the drilling plug, perforating and extruding cement, the cement job quality is good. The whole well construction period of 100 days, creating the fastest record of the old well plugging without trajectory of the fish type, providing technical support for the construction of Changchun gas storage, and providing experience for the same type of old well plugging and complex well treatment in China.

An Integrated Solution in Utilizing Active Magnetic Ranging to Seal Off Underground Gas Storage: Theoretical Analysis and Field Test

Summary In this paper, we describe a comprehensive technology based on an active magnetic ranging system (AMR) for sealing off the cement plug (CP) in the open hole (OH) section of the wellbore below the existing CP for underground gas storage. Utilizing depleted oil and gas reservoirs for natural gas storage is an important approach toward achieving carbon neutrality. Sealing off old wellbores is prioritized according to relevant standards. The challenge with OHs with CP is that there are no magnetic beacons in the wellbore, and the extent of compaction is unknown. Accurate placement of the seal-off CP is crucial because current technical methods, such as electromagnetic and acoustic waves, have limitations. Magnetic ranging technology, which is mature and widely used for wellbore interceptions or collision avoidance, requires magnetic beacons such as steel casing, drillpipes, or bottomhole assemblies left in the borehole. On the other hand, acoustic positioning techniques are applicable but presently complex to run operationally. In this paper, we propose a comprehensive control technology. It starts by measuring the positional relationship between the subject wellbore (SW) and a magnetic beacon wellbore (MBW) using AMR. The data are then used in combination with additional skew data along with associate positional uncertainty or ellipse of uncertainty (EOU) to determine the location of the target wellbore (TW) and the MBW. By calculating the relative positional relationship between the SW and the TW, OH reentry below CP can be achieved within the EOU below the sidetracking point. After reentry, specific work such as crushing, element logging, caliper logging, and full hydrocarbon gas detection is performed to verify if the TW is still in the original position and if the caprock is properly squeezed and sealed off. The comprehensive technique or method was tested on five wells in the Bohai Bay, successfully assessing the position of the OH wellbore and reentering below the CP. The process system expands the field of AMR and demonstrates significant industrial application value. It provides a new means of sealing off complex old wells.

Sand Production Prediction and Management Using a One-Dimensional Geomechanical Model: A Case Study in NahrUmr Formation, Subba Oil Field

Sand production in sandstone reservoirs is a complex problem for oil and gas companies. This problem can damage downhole equipment and surface production facilities. This paper presents a sand production case and quantifies sand risks for the NahrUmr formation located in Subbaoilfied.The risk of sanding or rock failure is commonly observed during production phases as well as drilling operations. A (1D) mechanical earth model was created using wireline log data and core data for estimating the formations mechanical properties.The extrapolation method is utilized for vertical stress prediction, whereas pore pressure and static Young’s modulus were calculated using Slowness Eaton method and John Fuller correlation respectively. The poro-elastic model was used to determine horizontal principal stresses and hydrocarbon intervals susceptible to sand production issues.The purpose of this study was achieved using Tech-Log software. Sand onset intervals are firstly predicted as an open hole using ten methods: Loading factor (LF), Critical drawdown pressure (CDDP), B-index, schlumberger (Sc), Elastic combination index (Ec-index), Interval Transit-Time (DTc), Total porosity method (PHIT), unconfined compressive strength (UCS), Shear modulus to bulk compressibility ratio (G/Cb), and shear failure method. Approximately ten methods refer to the same intervals that can produce sand. Secondly, sand depths were predicted by representing the well according to what actually existed as a cased hole by calculating the critical drawdown pressure (CDDP), which is calculated at various depletion rates (0%, 15%, 25%, and 35%) in order to measure the effect of reservoir pressure depletion on sand production. The results show that as the rock strength is increased, the amount of sand-free drawdown and depletion becomes larger. Also, a single-depth analysis was conducted for problem intervals, indicatg a sandwillproducefromdepth of 2527.7 m under certain conditions. Therefore, it is necessary to install sand control equipment in this well.

Effect of Coupling Ultrasonic Fatigue Strengthening and Polishing Methods on Open Hole Structures

Effect of Coupling Ultrasonic Fatigue Strengthening and Polishing Methods on Open Hole Structures

Analysis of thermal production effect of multi-horizontal U-shaped well

The multi-horizontal section hot dry rock (HDR) heat extraction system is proposed for efficient deep geothermal resources mining in this study. The thermal-hydraulic numerical model of the multi-horizontal section geothermal exploitation system is set up, the space-time evolution of temperature field is analyzed. The sensitivity factors including completion schemes, horizontal well diameter, quantity of horizontal sections and spacing of horizontal sections are investigated. The simulation results show that the production temperature and heating power of the multi-horizontal HDR production system decrease with the development of mining, and the decreasing speed gradually slows down. The open hole completion can be preferred when the formation conditions permit. The variation of horizontal well diameter has little effect on heat production when other conditions remain unchanged. The quantity of horizontal sections to be 3 or 4 for better heat extraction performance under the spacing of horizontal section remains 300m and the spacing of the horizontal section to be 150m is recommended within the scoped of this study. The results of this study can provide guidance for HDR mining research.

Pharmacological intervention of behavioural traits and brain histopathology of prenatal valproic acid-induced mouse model of autism.

Autism spectrum disorder (ASD) is one of the leading causes of distorted social communication, impaired speech, hyperactivity, anxiety, and stereotyped repetitive behaviour. The aetiology of ASD is complex; therefore, multiple drugs have been suggested to manage the symptoms. Studies with histamine H3 receptor (H3R) blockers and acetylcholinesterase (AchE) blockers are considered potential therapeutic agents for the management of various cognitive impairments. Therefore, the aim of this study was to evaluate the neuro-behavioural effects of Betahistine, an H3R antagonist, and Donepezil, an acetylcholinesterase inhibitor on Swiss albino mouse model of autism. The mice were intraperitoneally injected with valproic acid (VPA) on the embryonic 12.5th day to induce autism-like symptoms in their offspring. This induced autism-like symptoms persists throughout the life. After administration of different experimental doses, various locomotor tests: Open Field, Hole-Board, Hole Cross and behavioural tests by Y-Maze Spontaneous Alternation and histopathology of brain were performed and compared with the control and negative control (NC1) groups of mice. The behavioural Y-Maze test exhibits significant improvement (p <0.01) on the short term memory of the test subjects upon administration of lower dose of Betahistine along with MAO-B inhibitor Rasagiline once compared with the NC1 group (VPA-exposed mice). Furthermore, the tests showed significant reduction in locomotion in line crossing (p <0.05), rearing (p <0.001) of the Open Field Test, and the Hole Cross Test (p <0.01) with administration of higher dose of Betahistine. Both of these effects were observed upon administration of acetylcholinesterase inhibitor, Donepezil. Brain-histopathology showed lower neuronal loss and degeneration in the treated groups of mice in comparison with the NC1 VPA-exposed mice. Administration of Betahistine and Rasagiline ameliorates symptoms like memory deficit and hyperactivity, proving their therapeutic effects. The effects found are dose dependent. The findings suggest that H3R might be a viable target for the treatment of ASD.

Study on shear performance of BMSCC prefabricated shell and square steel tube composite permanent formwork beam

A novel type of permanent formwork (PF) concrete beam has been proposed with the aim of reducing carbon footprint, conserving energy, and enhancing construction efficiency. Specifically, the U-shaped PF is constructed using basic magnesium sulfate cement mortar, and square steel pipes with holes are utilized in place of traditional vertical and horizontal reinforcements. During on-site construction, the composite beam can be easily completed by pouring ordinary concrete into the PF. Shear failure tests were conducted on two PF beams and a reinforced concrete (RC) contrast beam with varying strip spacing. It was observed that the remaining rectangular steel strips, resulting from opening holes on both sides of the square steel pipe, acted as shear stirrups. The results indicate that the PF beam demonstrates typical shear and compression failure, and the precast shell is securely bonded to the core concrete without any peeling phenomenon. When comparing to an equivalent RC beam with the same transverse steel yield strength and dosage, the cracking load of the inclined section is increased by 28.3 % and the ultimate load is increased by 21.4 %. Compared to RC beams, PF beams exhibit an increased number of cracks but reduced width. And The ductility of PF beams were improved. Decreasing the distance between steel strips on both sides of the PF beam results in an 10.3 % increase in cracking load and a 9.4 % increase in ultimate load. By introducing the concrete constraint coefficient and the steel tube web resistance coefficient, the formula for calculating the shear capacity of the PF beam was established.