Block Mode Research Articles

Analysing Block Stability under Varying Resultant Force for Arbitrary Shapes

Block theory is a basis theory in Rock mechanism taking advantages of analysing finiteness, removability, and mechanical stability of convex blocks under different engineering conditions. However, classic block theory does not give solutions for non-convex blocks which are very common in civil project, such as underground edges, corners, and portals. To enhance availability of block theory, a general algorithm which can analyse stability of blocks with arbitrary shapes is proposed in this paper. In the proposed algorithm, the joint pyramid for block of arbitrary shapes can be computed, sliding mode of block under varying resultant force can be seen immediately from 3D view by means of an interactive visualization mechanism, and parallel or nonadjacent sliding faces of blocks are determined immediately for given resultant force. With this algorithm, blocks of arbitrary shapes can be analysed, and users do not need to interpret graphs of block theory to take advantage of its accuracy and effectiveness. The validation of the proposed algorithm is verified, and it was used to investigate the stability of the left bank rock slope of a dam. The results show that the algorithm is correct, effective, and feasible for use in rock engineering project.

Pain management during labor: use of intermittent drug delivery devices for improvement of obstetric and neonatal outcome and reduction of healthcare burden: A large non-inferiority randomized clinical trial

BackgroundAutomated continuous epidural administration of local anesthetics provides a more stable analgesic block with decreasing of healthcare staff compared to manual boluses administration (TOP-UP) but is associated to high rate of operative vaginal delivery. We hypothesized that the use of programmed intermittent automated boluses (PIEB) is able to provide a good quality of analgesia and decreasing of anesthesiologic workload without increasing the rate of instrumental vaginal birth in comparison with TOP-UP technique. Laboring nulliparous woman aged between 18 and 46 years were randomized to epidural analgesia with 0.0625% levobupivacaine and sufentanil administered by PIEB or by TOP-UP techniques. Primary outcome was instrumental vaginal delivery rate and secondary outcomes were quality of analgesia, total and time-related drugs doses used, motor block, newborn outcome, and anesthesiologic workload.ResultsSix hundred twenty-nine were randomized, and 628 were included in the intention-to-treat analysis. The rate of instrumental vaginal delivery was similar in the PIEB and TOP-UP groups (13.2% vs 9.7%, OR 1.4 95% CI 0.8 to 2.5; p 0.21). There was no difference between groups regarding mode of delivery (cesarean section vs vaginal birth), newborn outcome, and motor block. Patients in the PIEB group received more total and time-related drugs doses and a better quality of analgesia. Anesthesiological workload was significantly reduced in the PIEB group.ConclusionsOur study demonstrated that epidural anesthesia with programmed intermittent epidural boluses by an automated device provides an effective and safe management of labor analgesia with improvement of pain control and sparing of man workload compared to manual top-up protocols.

Academics Embrace Disruption: Lessons Learned Teaching First Year Law During a Pandemic

This study reports on the teaching practices adopted by a cohort of higher education academics for online and remote delivery of first year law units (subjects) as a result of the COVID-19 pandemic. Six academic staff who taught nine units face-to-face in intensive Block mode shifted their teaching online almost overnight, including conducting synchronous face-to-face teaching online. Their interview comments are initially categorised using a SWOT (strengths-weaknesses-opportunities-threats) analysis approach, then further analysed according to the elements in Moore’s transactional distance theory - dialogue, structure and learner autonomy. The study identified that while the unit space on the learning management system with links to resources and readings, scaffolded learning activities, structured interactions with clear instructions and assessments was the greatest asset, it also offered opportunities that were both practical and unexpected. While it gave academics a strong footing to commence their remote teaching, the key weakness was the loss of face-to-face contact, now replaced by Zoom. This posed threats related to learning. The findings offer suggestions and pedagogical interventions that can be applied to modify teaching practices in remote Block delivery in a post-COVID future in teaching first-year law. The research is equally applicable to teaching any discipline online.

Di (2-ethyl-hexyl) phthalate disrupts placental growth in a dual blocking mode

Di (2-ethyl-hexyl) phthalate (DEHP) is a widely used plasticizer. Maternal DEHP exposure inhibits cell proliferation and reduces placentas size, which associates with fetal growth restriction and adulthood diseases. However, the mechanism of placental cell proliferation inhibition by DEHP remains elusive. This study investigated the effect of DEHP on placental cell proliferation from cell cycle arrest. Utilizing in vitro and in vivo experiments, we investigated cell cycle arrest, DNA double-strand break (DSB) repair, genotoxic stress response, and micronuclei formation. Most DEHP metabolizes to mono (2-Ethylhexyl) phthalate (MEHP) and distributes to organs quickly, so MEHP and DEHP were used in cultured cell and animal experiments, respectively. Here, a double blocking mode for the proliferation inhibition of the placental cell was revealed. One is that the classical DSB repair pathways were suppressed, which arrested the cell cycle at the G2/M phase. The other is that DEHP stimulated an elevated level of progesterone, which blocked the cell cycle at metaphase by disrupting chromosome arrangement. These two sets of events facilitated micronuclei formation and resulted in cell proliferation inhibition. This findings provide a novel mechanistic understanding for DEHP to inhibit placental cell proliferation.

Analysis of Public Space in Historic Districts of Historic Cities Based on Community Governance

Purpose: Based on the perspective of community governance, the paper explores the research path of public space renewal in historic city districts. Taking the historical public space of Lhasa City as an example, this paper analyzes the causes of the characteristics of public space, analyzes the logical relationship between public space and urban renewal and community governance, and finally optimizes the pattern of historical public space of Lhasa City by improving the spatial structure. Create intelligent living blocks and optimize the life mode of historical blocks; Significance: From the human-oriented perspective, the exploration of the public space renewal in the Historic Districts was in essence a process in which people develop continuously and their needs are continuously satisfied. It could meet the multi-level needs of residents at different stages. Secondly, from a social perspective, the innovative pattern of community governance could help achieve self-satisfaction within the district, radiate to the surrounding industries, and relieve the pressure of social employment. Thirdly, from the perspective of urban renewal implementation, the research on the public space renewal the Historic Districts would help promote the balance of social ecological environment, improve the regional governance and promote the high-quality development of the city.

The effectiveness of “Soft-blocking” for reducing clicking on-screen while driving

Smartphone usage while driving is recognized as a compromise on road safety. We investigated if silencing and hiding of notifications from drivers (soft blocking) can reduce clicks on the screen while driving and if the effect of the soft blocking would be different for different speed thresholds (STs) (i.e., at driving speed greater than 0 km/h, greater than 1 km/h….and greater than 90 km/h). Drivers installed a smartphone application, which continuously monitored their phones. In the intervention group (N = 22), the application switched to the soft blocking mode during the study's intervention period, while in the control group (N = 29) it remained in a recording-only mode. We ran a Poisson regression model on the click events frequency (CEF) to estimate the soft blocking effect for each of the STs between 0 and 90 km/h. Our analyses indicated that the soft blocking effectiveness was indeed speed-dependent and pointed to a decline in CEF from ST > 55 km/h and to mixed results if ST < 55 km/h. We identify a potential of soft blocking to reduce phone usage while driving and recommend ST-dependent soft blocking. We also recommend using different STs in future investigations on the effectiveness of soft blocking.

Regulation of Cooling Mode of Thermoelectric Bloc

With the help of a computational model, the cooling modes of a block of a thermoelectric refrigeration unit designed for ship's provision and freezing chambers are studied. The computational model, based on the numerical solution of a system of nonlinear algebraic equations, takes into account the operating characteristics of a serial thermoelectric module and the thermal resistances of heat removal and supply devices. The dependences of the cooling power and the coefficient of performance of the block on the supply current of the thermoelectric modules are calculated. The analysis of the cooling modes of the thermoelectric block is carried out and recommendations for regulating the current strength depending on the current temperature conditions in the provision and freezing chambers are developed

Manual Aspiration Thrombectomy for Embolic Acute Mesenteric Ischemia.

A 65-year-old woman was admitted with diffuse abdominal pain, diarrhea, and hematochezia of one day's duration. Her medical history included surgical repair of an anterior mitral valve cleft and an associated ostium primum atrial septal defect, implant of a single-chamber pacemaker programmed in VVIR mode for complete atrioventricular block, and stroke despite appropriate anticoagulant therapy for paroxysmal atrial fibrillation (AF). At admission, the patient had been on chronic anticoagulant therapy with acenocoumarol (target international normalized ratio, 3.0). Mesenteric arterial embolization was highly suspected.Abdominal computed tomographic angiograms revealed a large thrombus in the first 5 cm of the superior mesenteric artery (SMA) distal to its ostium (Fig. 1). Within 6 hours, this finding was confirmed on a mesenteric angiogram (Fig. 2A). Access was obtained by introducing a 6F angiographic catheter into the right brachial artery and advancing it to the SMA. Next, the 6F angiographic catheter was exchanged for a 6F multipurpose guiding catheter. Under fluoroscopic guidance, the multipurpose catheter was passed through the thrombotic segment several times. A large amount of thrombotic material was manually aspirated from the SMA and its branches by means of suction from a large-bore 50-mL syringe connected externally to the guiding catheter (Fig. 2B). A final postprocedural mesenteric angiogram confirmed thrombus removal (Fig. 2C), which was accompanied by prompt relief of symptoms and normalization of laboratory values.The thrombotic event was considered embolic, given the patient's history of stroke despite anticoagulant therapy, incomplete occlusion of the SMA just distal to its ostium, and the absence of ostial calcified atherosclerosis. The patient's anticoagulation regimen was switched from acenocoumarol to apixaban 5 mg 2×/d and clopidogrel 75 mg/d. Four days after the thrombectomy and an uncomplicated course of recovery, she was discharged from the hospital. At one-year follow-up, she had experienced no recurrent cardioembolic events.Acute mesenteric ischemia is typically caused by SMA emboli and, despite advances in endovascular therapy, is associated with high morbidity and mortality rates.1 Early diagnosis and revascularization are essential to prevent intestinal complications. However, because acute mesenteric ischemia is rare and often associated with nonspecific abdominal pain, diagnosis is difficult. This is particularly relevant in patients with AF, in whom early evaluation by computed tomographic angiography is crucial.2 The development of thrombosis despite appropriate anticoagulation for comorbid AF puts patients at high risk for bleeding during surgery and thus poses additional therapeutic challenges. For patients who are promptly diagnosed and show no signs of advanced bowel ischemia, percutaneous revascularization is a viable option.3 If an aspiration catheter is not available, manual aspiration thrombectomy is feasible.Section editor: Raymond F. Stainback, MD

DNA origami single crystals with Wulff shapes

DNA origami technology has proven to be an excellent tool for precisely manipulating molecules and colloidal elements in a three-dimensional manner. However, fabrication of single crystals with well-defined facets from highly programmable, complex DNA origami units is a great challenge. Here, we report the successful fabrication of DNA origami single crystals with Wulff shapes and high yield. By regulating the symmetries and binding modes of the DNA origami building blocks, the crystalline shapes can be designed and well-controlled. The single crystals are then used to induce precise growth of an ultrathin layer of silica on the edges, resulting in mechanically reinforced silica-DNA hybrid structures that preserve the details of the single crystals without distortion. The silica-infused microcrystals can be directly observed in the dry state, which allows meticulous analysis of the crystal facets and tomographic 3D reconstruction of the single crystals by high-resolution electron microscopy.

A Study on Optimization of Planar Gate Type Metal-Oxide-Semiconductor Field-Effect-Transistors Multi Epitaxial Process in Super-Junction Structure

Power metal-oxide-semiconductor field-effect-transistors (MOSFET) is a high voltage control device that requires high reliability and efficiency and is used to improve efficiency in areas such as renewable energy generators, electric vehicles, power supply unit, converters and motor control. Electrical characteristics of the MOSFET include a Threshold voltage which is a voltage for operating the device, an On-resistance which is a device resistance in an on-state, and a breakdown voltage which means a device withstand voltage. A Super-Junction structure is proposed to design the device with a high breakdown voltage and a low on-resistance. A multi-epitaxial Super-Junction MOSFET forms a Pillar layers by injecting continuously P-type impurity at edge on stacked N-Pillar layer. By forming the Pillar region which is higher doping concentration than N-drift, the on resistance can be reduced. In the forward blocking mode, the depletion layer of the Pillar region is extended to both vertical and horizontal sides, for a high breakdown voltage can be obtained. By using a T-CAD tool which is a process simulator, electrical characteristics of 1,200 V class super-junction MOSFET are analyzed along process variables (pillar lateral length, pillar concentration). When the breakdown voltage of the super junction MOSFET and the Planar MOSFET are equal, On-resistance (based on 10 A) has a gain of approximately 20% by a difference of 0.189 ohm×cm. It is believed that this can contribute to the development of super junction MOSFET with improved reliability and electrical characteristics.

A Participatory Evaluation of Transforming First Year LLB Into Block Mode

This paper adopts a participatory evaluation approach to identify successes and challenges experienced by a group of academics in redesigning and delivering the first year of the Law degree (LLB) in block mode in an Australian university. This transformation into an intensive four-week block necessitated an overhaul of curricula, assessment regimes, teaching practices and delivery processes. The evaluation of the academics staff experience focused on five themes: (1) course design and development, (2) satisfying learning outcomes and accreditation standards, (3) implementing student engagement strategies, (4) embedding block mode principles, and (5) establishing effective assessment regimes. For each theme, participants identified the successes, challenges, and lessons learned. The study highlighted the value of early design-specialist involvement and collaboration in course design including the importance of being aware of the legal accreditation body requirements. The criticality of focused active learning and the need to balance lecture-style delivery with knowledge-consolidating practical legal analysis exercises was emphasised. Also stressed was wellbeing, including sensitivity to individual student circumstances and strategies that successfully manage staff and student workloads alongside academic integrity. Unintended benefits such as professional learning through the collaboration, refining personal thinking related to pedagogy in the block were consequences of this evaluative approach.

A Molecular Lid Mechanism of K+ Channel Blocker Action Revealed by a Cone Peptide

Many venomous organisms carry in their arsenal short polypeptides that block K+ channels in a highly selective manner. These toxins may compete with the permeating ions directly via a “plug” mechanism or indirectly via a “pore-collapse” mechanism. An alternative “lid” mechanism was proposed but remained poorly defined. Here we study the Drosophila Shaker channel block by Conkunitzin-S1 and Conkunitzin-C3, two highly similar toxins derived from cone venom. Despite their similarity, the two peptides exhibited differences in their binding poses and biophysical assays, implying discrete action modes. We show that while Conkunitzin-S1 binds tightly to the channel turret and acts via a “pore-collapse” mechanism, Conkunitzin-C3 does not contact this region. Instead, Conk-C3 uses a non-conserved Arg to divert the permeant ions and trap them in off-axis cryptic sites above the SF, a mechanism we term a “molecular-lid”. Our study provides an atomic description of the “lid” K+ blocking mode and offers valuable insights for the design of therapeutics based on venom peptides.

Block Mode Study: Opportunities and Challenges for a New Generation of Learners in an Australian University

This article is an update on a university-wide overhaul of its pedagogy, curriculum and delivery to support the expanding non-traditional, new generation learners while enhancing opportunity and success for traditional learners. The Block Model developed by Victoria University (VU), Australia for its undergraduate cohort, was a bold response to support all students including its high proportion of First-in-family (FiF), low socio-economic status (LSES), and non-English-speaking background (NESB) students. In this radical new hybrid Block model, students study one unit/subject at a time over four weeks. The article reports on preliminary results after two years of implementing the VU Block Model. While both traditional and new-generation cohorts significantly improved their performance, there was a higher improvement in the pass rates of LSES, NESB and FiF students, compared to the improvements in the traditional cohorts of students. These initial results confirm the value of the institution-wide strategy to expand opportunity and enhance success for all.

Multi-floating-zone JTE for 4.5 kV SiC power devices with exponentially modulated dimensions

We propose a new multi-floating-zone junction-termination-extension (MFZ-JTE) using an exponentially modulated space and width for 4.5 kV SiC power devices to effectively spread out the electric field in reverse blocking mode and improve the tolerance against imprecise process control. A modified MFZ-JTE design with an exponential model was also proposed considering a stable patterning process. The blocking characteristics of the proposed MFZ-JTE using various exponential coefficients (α) in the model were evaluated for undesirable variations in the fabrication processes through TCAD simulations. The modified design for a 4.5 kV MFZ-JTE with α = 0.046 exhibited a low breakdown voltage deviation of 0.13% when the space variation ranged from –0.2 to +0.2 μm and 0.14% when the variation in the surface charge density at the SiO2/SiC interface was within the range of 0 to –1 × 1012 cm–3.

Enzymatic Cleaning Mitigates Polysaccharide-Induced Refouling of RO Membrane: Evidence from Foulant Layer Structure and Microbial Dynamics.

Traditional harsh chemical cleaning-in-place (CIP) is corrosive to membranes but has limited inhibition on refouling, a tough problem for long-term operation of reverse osmosis (RO). Mild enzymatic cleaning (at pH 9) is a promising alternative but lacks long-term verification and insightful elucidation. In this study, we investigated the instantaneous efficiency, postcleaning refouling, and biological effect of enzymatic CIP (compounded with lipase, protease, and sodium dodecyl sulfate) on practical RO membranes during a 500 h multicycle operation. The enzymatic CIP had an average cleaning efficiency of 77%, which is comparable to a commercial harsh CIP benchmark (pH > 12). It mitigated refouling by shaping the biofilm into a loose and porous architecture where newly arrived organics conformed standard blocking, whereas harsh chemicals rendered a smooth and dense gel layer with quick refouling in intermediate blocking or cake filtration mode. Such structural disparities were dominated by polysaccharides according to quantitative chemical analyses. Gene sequencing and ecological network analysis further proved that the behavior of polysaccharide-related keystone species (such as Sphingomonas and Xanthomonas) significantly changed after long-term enzymatic treatment. In this regard, the mild selective pressure of enzymatic reagents can directionally regulate microbial dynamics, alter foulant layer structure via bio-organic synchronicity, mitigate refouling, and eventually improve the sustainability of RO operation.

Block mode delivery in an andragogic environment: challenges and strategies

Block mode of delivery, a distinct form of accelerated/intensive course offering, has witnessed significant growth in recent years in higher education. However, despite the increase in popularity, academic enquiry into block mode delivery has been scarce. This formed the motivation of this study where a comprehensive understanding on the challenges and strategies for improving block mode teaching is developed based on multiple interviews with academics involved in block mode delivery in the UAE. The study found ten key challenges impacting block mode delivery and nine strategies to minimise/eliminate these challenges. The findings are expected to provide academics, policymakers and institutions in the UAE higher education sector, and in general, key insights into the effective design, delivery, and management of courses in block mode. An investigation on block-mode teaching in the UAE higher education has not been previously attempted and constitutes the novelty of this work.

Time-space evolution of the goods export network of the Belt and Road countries: The view of weighted complex network

The weighted complex network is utilized to analyze the evolution of the overall structural features of the goods export network and the role transitions of each country in the network. The research suggests: 1. The network of exports of the Belt and Road countries has transformed from multi-core pattern into one extreme along with multi-core pattern; 2. China, South Korea, Russia, Singapore and Italy are the highest-ranking countries in the network. Among these countries, the influence of China is on the rise, South Korea South Korea’s influence remains basically unchanged., however, Russia, Singapore and Italy are on the decline; 3. The leading edge of Asia-Pacific block in the network has been enhanced year by year. Not only has the trade volume within the block increased to 50% of the whole network, but the trade export to other three blocks has significant increasement. The total volume of trade in European block increased greatly and its block mode has transformed from external to universal. The trade volume of the former Soviet Union block along with the West Asia-Africa block increased significantly as well, but there is still a large gap compared with the European block and Asia-Pacific block.

Research on the Perception of Historical District of Eight Great Passes in Qingdao Based on Online Travel Notes

In recent years, the protection mode of historical blocks has changed from simple material protection to comprehensive protection integrating various factors, and more and more attention has been paid to the role of human perception. How to pay attention to the practical experience of consumers while protecting has become the main problem. This paper studies the tourists' perception of historical district of Eight Great Passes in Qingdao by using the method of network text analysis, and carries out word frequency analysis, semantic network analysis and emotional analysis on the online travel notes by Rost CM6, so as to comprehend the current situation of tourists' perception of different dimensions of Eight Great Passes historical and Cultural District in Qingdao, and find out the problems in its development as well as put forward the sustainable development strategies

Block mode delivery in an andragogic environment: challenges and strategies

Block mode delivery in an andragogic environment: challenges and strategies

Gradient-Based Intraprediction Fusion for Video Coding

Video coding is more important than ever due to emergence of larger resolutions, new formats requiring higher bandwidths, prevalence of new video services, etc. Consequently, new codecs are designed to minimize transmission rates of such contents without sacrificing quality. This article proposes an intraprediction solution for future video codecs that save the bit rates of intramode signaling for luminance and chrominance blocks. In doing so, modes are implicitly derived at the decoder side through a gradient-based analysis. In contrast to state-of-the-art intraprediction that uses a single mode for a luma block, the proposed method offers a combination of multiple derived modes. Furthermore, the chrominance components Cb/Cr are allowed to have their separate modes, instead of sharing one mode. The implementation of the proposed method in the Versatile Video Coding reference software (VTM) provides 0.72% Bjontegaard-delta rate saving, with run-time complexity of 110% and 104% at the encoder and decoder sides, respectively.