Variable Block Research Articles

High Speed Parallel SAD Architecture Implementation on FPGA for HEVC encoder

Video compression is a very complex and time consuming task which generally pursuit high performance. Motion Estimation (ME) process in any video encoder is responsible to primarily achieve the colossal performance which contributes to significant compression gain. Summation of Absolute Difference (SAD) is widely applied as distortion metric for ME process. With the increase in block size to 64×64 for real time applications along with the introduction of asymmetric mode motion partitioning(AMP) in High Efficiency Video Encoding (HEVC)causes variable block size motion estimation very convoluted. This results in increase in computational time and demands for significant requirement of hardware resources. In this paper parallel SAD hardware circuit for ME process in HEVC is propound where parallelism is used at various levels. The propound circuit has been implemented using Xilinx Virtex-5 FPGA for XC5VLX20T family. Synthesis results shows that the propound circuit provides significant reduction in delay and increase in frequency in comparison with results of other parallel architectures

Cardiac arrhythmias in patients with chronic autoimmune diseases

Chronic inflammation due to autoimmune diseases is associated with ahigher rate of supraventricular and ventricular arrhythmias leading to an increased risk for cardiovascular morbidity and mortality. Involvement of the cardiac conduction system is common in patients with chronic autoimmune diseases, although the penetrance of clinical signs and symptoms is variable and complete heart block with need for therapy is rare. The combination of the increased prevalence of structural cardiovascular disease and the direct impact of inflammatory mechanisms on cardiac electrophysiology seems to be responsible for the higher rate of tachyarrhythmias. In particular, fibroblast activation, gap junction impairment via changes in connexin composition and abnormalities in intracellular calcium-handling are mentioned. Electrocardiographic markers of an increased arrhythmogenic potential in patients with chronic autoimmune disorders may include prolonged P‑wave duration as well as abnormal QTc interval and reduced heart rate variability. Thus, minimizing the inflammatory burden through tight control of disease activity may help reduce the arrhythmic load.

An Effectual Homomorphic Tag Based Block for Dynamic Provable Data Possession Framework Based on Block Tagging the Cloud File

Storing the data in cloud helps in satisfying the demand of data access at anyplace, anytime. In cloud storage, users authenticate whether the data has been stored to the cloud storage server correctly. In order to enhance the storage provision, an Effectual Homomorphic Tag based Block for Dynamic Provable Data Possession (EHTB-DPDP) framework has been designed. This framework checks for the data integrity in the cloud storage server. The existing PDP, DPDP schemes were analyzed and the drawbacks encountered in those systems have been reframed using the proposed methodology. The major benefit of the proposed EHTB-DPDP is that it offers an effectual dynamic provable data possession and data integrity. This scheme spotlights on the integrity of the remote data by reducing data storage space, so that users can retrieve data efficiently. This security enhancement is achieved by the block tagging methodology. In addition, converting the variable block size to the fixed block size using hash function is also investigated. The feasibility of the scheme is proved by aanlyzing the security and the performance

Investigating the potential of using glass foam for an EMAS material to mitigate aircraft overrun accidents

ABSTRACT An aircraft overrun occurs when an aircraft is unable to stop within the runway design length. Commercial airports are required to have a 305 m (1000-ft) runway safety area (RSA) at each runway end to avail an aircraft adequate length for stoppage during an overrun. At airports where this space is unavailable, the Federal Aviation Administration (FAA) allows for an airport to use an Engineered Materials Arresting System (EMAS). An EMAS is positioned within the RSA and is comprised of an energy absorbing material that brings the aircraft to stoppage through drag forces developed at the tire-EMAS interface. EMAS are constructed using low-density 1.21 m × 1.21 m (4-ft × 4-ft) variable thickness cementitious blocks. The blocks are aligned adjacent to one another to form a rectangular EMAS bed within the RSA. This article presents the computer code, SGAS, developed by the author to predict aircraft stopping distance and behaviour of current aircraft types within an EMAS. The SGAS computer code is validated with results from the FAA ARRESTOR computer code. After validating the SGAS computer code, this article investigates the potential for using glass foam blocks as an alternative EMAS material.

Preconditioning a Newton-Krylov solver for all-speed melt pool flow physics

In this paper, we introduce a multigrid block-based preconditioner for solving linear systems arising from a Discontinuous Galerkin discretization of the all-speed Navier-Stokes equations with phase change. The equations are discretized in conservative form with a reconstructed Discontinuous Galerkin (rDG) method and integrated with fully-implicit time discretization schemes. To robustly converge the numerically stiff systems, we use the Newton-Krylov framework with a primitive-variable formulation (pressure, velocity, and temperature), which is better conditioned than the conservative-variable form at low-Mach number. In the limit of large acoustic CFL number and viscous Fourier number, there is a strong coupling between the velocity-pressure system and the linear systems become non-diagonally dominant. To effectively solve these ill-conditioned systems, an approximate block factorization preconditioner is developed, which uses the Schur complement to reduce a 3×3 block system into a sequence of two 2×2 block systems: velocity-pressure, vP, and velocity-temperature, vT. We compare the performance of the vP-vT Schur complement preconditioner to classic preconditioning strategies: monolithic algebraic multigrid (AMG), element-block SOR, and primitive variable block Gauss-Seidel. The performance of the preconditioned solver is investigated in the limit of large CFL and Fourier numbers for low-Mach lid-driven cavity flow, Rayleigh-Bénard melt convection, compressible internally heated convection, and 3D laser-induced melt pool flow. Numerical results demonstrate that the vP-vT Schur complement preconditioned solver scales well both algorithmically and in parallel, and is robust for highly ill-conditioned systems, for all tested rDG discretization schemes (up to 4th-order).

Graph CNNs with Motif and Variable Temporal Block for Skeleton-Based Action Recognition

Hierarchical structure and different semantic roles of joints in human skeleton convey important information for action recognition. Conventional graph convolution methods for modeling skeleton structure consider only physically connected neighbors of each joint, and the joints of the same type, thus failing to capture highorder information. In this work, we propose a novel model with motif-based graph convolution to encode hierarchical spatial structure, and a variable temporal dense block to exploit local temporal information over different ranges of human skeleton sequences. Moreover, we employ a non-local block to capture global dependencies of temporal domain in an attention mechanism. Our model achieves improvements over the stateof-the-art methods on two large-scale datasets.

Comparative Study of DDS with Different Types of Phase Accumulators

The paper deals with the problems of delayed transfer signals in the direct digital synthesizer (DDS) phase accumulator adders. Transfer delay is one of the factors that affect the maximum output frequency of the DDS synthesizer. The main types of adders used in DDS synthesizers are described. Separately, attention was paid to the adder with a consistent transfer of the transfer signal, adders with a transmission carry signal with a fixed block length, adders with a signal transmission delay with a variable block length, and a mathematical analysis of the origin and duration of the delay of the transfer signal in them. It was found that the use of a transfer adder with a variable length of a block in the core of a direct digital synthesizer would increase the maximum output frequency by 2.4 times compared to the adder with a parallel transfer, and by 1.43 times as compared with the adder with a fixed length the block.

Military-Applied Means of Physical Education in Pre-University Educational Institutions of the Russian Ministry of Defence

Introduction.. The main purpose of pre-university educational institutions of the Ministry of Defence ofRussia, e.g. Suvorov Military Schools, Nakhimov Naval Schools, presidential schools and cadet corps, is to educate graduates, who are highly motivated and sufficiently prepared for military vocational activities, including graduates’ general physical fitness. Successful performance of the task is complicated by the fact that educational process in such organisations has a general educational orientation, which is common for the entire system of school education. However, it is obvious that the specifics of the mission of preuniversity educational institutions of the Ministry of Defence of the Russian Federation requires more intensive physical activities, which improve health and increase physical endurance of students, taking into account their age-specific physiological characteristics. In this regard, it is necessary to develop a variable methodological block as a supplement to an invariant part of the main programme of physical culture, which will be aimed at stimulating the development of motor and power capabilities, skills and professionally significant qualities of future military personnel.The aim of the research was to select and scientifically justify the introduction of appropriate and effective means for high-school students’ physical education in pre-university educational institutions of the Ministry of Defence ofRussia.Methodology and research methods. To identify the appropriate ways of solution of the problems of profile physical education of potential officers at the stage pre-professional development, the methodological framework was based on the theory of physical culture and sport, individually-modular approach to the development of the system of professional and applied physical training, its principles and regularities, conceptual provisions of health preservation in adolescence and youth. In the course of the research, the authors thoroughly studied the scientific and methodological sources, regulatory and legal base of the organisation of educational process, questions of its planning and control of all forms and activities of students’ physical training in military schools. The following methods were applied: interview, pedagogical observation, questionnaire survey, technique of entrance and final testing of selection of the research participants, formative experi ment, monitoring, comparative analysis and systematisation of indicators (resultant scores) of sports achievements of examinees. Experimental data were processed by the methods of mathematical statistics.Results and scientific novelty. The selection of means of physical training in pre-university all-service military and naval educational institutions was made on the basis of theoretical and statistical material of analytical review and collected empirical data and pedagogical experience in 17 pre-university educational institutions of the Ministry of Defence of Russia (n = 607). The list of the most productive means is made. The quantitative ratio of military-applied methods, which positively influence the system of physical training in the 10th-11th grades, is established. The pilot testing showed that systematic use of special training exercises of military-applied orientation significantly improves the indicators of physical training of students. The analysis of students’ questionnaires before and after the experiment revealed strengthening of students’ moral stability, growing interest in military science and motivation to studying of an applied training material, as well as significant increase in the number of applicants seeking to continue their training in higher educational institutions of the Ministry of Defence of the Russian Federation and to dedicate their lives to military service. The proposals and practical recommendations on purposeful introduction of complexes of specialised physical exercises and elements of disciplines of military-applied sports to educational process are formulated.Practical significance. The results of the research can be employed to plan and organise physical training of high-school students of pre-university educational institutions of the Ministry of Defence ofRussia as additional programme and methodological support at the initial stage of military-applied physical training of future military specialists.

Dampak Pertumbuhan Ekonomi China Terhadap Perekonomian Indonesia

This study aims to analyze the impact of China’s economic growth on the Indonesian economy. In this analysis, the study adapted SVAR with block exogeneity consisting of blocks global variable (China’s economic growth and non-fuel global commodity prices growth) and domestic variable blocks (economic growth, inflation, real interest rates and Indonesia’s exchange rates). Using the data over the period from 1993q1-2017q2, this study found that the shock if China’s economic growth had a major impact on non-fuel global commodity price movements. Additionally, it is also acknowledged that China’s economic growth shock of 1.9 percent causes the Indonesian economy to grow by 0.85 percent. This was due to the appreciation of Rupiah exchange rate againt US Dollar by 1.6 percent, make inflation under control, while inflation in term of rising price index was insignficant

Metaheuristic algorithms for the hybrid flowshop scheduling problem

The hybrid flowshop scheduling problem (HFSP) has been widely studied in the literature, as it has many real-life applications in industry. Even though many solution approaches have been presented for the HFSP with makespan criterion, studies on HFSP with total flow time minimization have been rather limited. This study presents a mathematical model, four variants of iterated greedy algorithms and a variable block insertion heuristic for the HFSP with total flow time minimization. Based on the well-known NEH heuristic, an efficient constructive heuristic is also proposed, and compared with NEH. A detailed design of experiment is carried out to calibrate the parameters of the proposed algorithms. The HFSP benchmark suite is used for evaluating the performance of the proposed methods. As there are only 10 large instances in the current literature, further 30 large instances are proposed as new benchmarks. The developed model is solved for all instances on CPLEX under a time limit, and the performances of the proposed algorithms are assessed through comparisons with the results from CPLEX and the two best-performing algorithms in literature. Computational results show that the proposed algorithms are very effective in terms of solution time and quality. Additionally, the proposed algorithms are tested on large instances for the makespan criterion, which reveal that they also perform superbly for the makespan objective. Especially for instances with 30 jobs, the proposed algorithms are able to find the current incumbent makespan values reported in literature, and provide three new best solutions.

Telemonitoring-supported exercise training, metabolic syndrome severity, and work ability in company employees: a randomised controlled trial

Metabolic syndrome is a predisposing factor for cardiovascular and metabolic disease, but also has socioeconomic relevance by affecting the health and productivity of workers. We tested the effect of regular telemonitoring-supported physical activity on metabolic syndrome severity and work ability in company employees. This was a prospective, randomised, parallel-group, and assessor-blind study done in workers in the main Volkswagen factory (Wolfsburg, Germany). Volunteers with diagnosed metabolic syndrome according to American Heart Association/National Heart, Lung, and Blood Institute criteria were randomly assigned (1:1) to a 6-month lifestyle intervention focusing on regular exercise (exercise group), or to a waiting-list control group, using a computer-based assignment list with variable block length. Participants in the exercise group received individual recommendations for exercise at face-to-face meetings and via a smartphone application, with the aim of doing 150 min physical activity per week. Activities were supervised and adapted using activity-monitor data, which were transferred to a central database. Participants in the control group continued their current lifestyle and were informed about the possibility to receive the supervised intervention after study completion. The primary outcome was the change in metabolic syndrome severity (metabolic syndrome Z score) after 6 months in the intention-to treat population. This trial is registered with ClinicalTrials.gov, number NCT03293264, and is closed to new participants. 543 individuals were screened between Oct 10, 2017, and Feb 27, 2018, of whom 314 (mean age 48 years [SD 8]) were randomly assigned to receive the intervention (n=160; exercise group) or to a waiting list (n=154; control group). The mean metabolic syndrome Z score for the exercise group was significantly reduced after the 6-month intervention period (0·93 [SD 0·63] before and 0·63 [0·64] after the intervention) compared with the control group (0·95 [0·55] and 0·90 [0·61]; difference between groups -0·26 [95% CI -0·35 to -0·16], p<0·0001). We documented 11 adverse events in the exercise group, with only one event (a twisted ankle) regarded as directly caused by the intervention. A 6-month exercise-focused intervention using telemonitoring systems reduced metabolic syndrome severity. This form of intervention shows significant potential to reduce disease risk, while also improving mental health, work ability, and productivity-related outcomes for employees at high risk for cardiovascular and metabolic disease. Audi BKK health insurance and the German Research Foundation through the Cluster of Excellence REBIRTH.

A study protocol for the N-ICE trial: A randomised double-blind placebo-controlled study of the safety and efficacy of N-acetyl-cysteine (NAC) as a pharmacotherapy for methamphetamine (\u201cice\u201d) dependence

BackgroundThere are currently no approved pharmacotherapies for managing methamphetamine dependence. N-acetylcysteine (NAC) has been found to reduce the craving for methamphetamine and other drugs, but its effect on methamphetamine use and other clinically related endpoints are uncertain. The N-ICE trial is evaluating the safety and efficacy of NAC as a take-home pharmacotherapy for methamphetamine dependence.Methods/designThis is a two-arm parallel double-blind placebo-controlled three-site randomised trial (ratio 1:1) using permuted block randomisation, with variable block sizes. It is stratified by site, sex and whether the methamphetamine is injected or not. Participants (N = 180; 60 per site) need to be dependent on methamphetamine, interested in reducing their methamphetamine use and not currently receiving treatment for substance use disorders. The trial is being conducted in outpatient settings in Melbourne, Geelong and Wollongong, Australia. Participants will receive either 2400 mg oral NAC or a matched placebo, delivered as a take-home medication for 12 weeks. Two 600 mg capsules are self-administered in the morning and two more in the evening. Adherence is being monitored using eCAP™ medication bottle lids, which record the date and time of each occasion the bottle is opened. The primary outcome is methamphetamine use during the 12-week trial medication period, measured as (a) days of use, assessed using the timeline followback, and (b) methamphetamine-positive saliva tests, taken weekly. Secondary measures include weekly assessment of methamphetamine craving, severity of methamphetamine dependence, methamphetamine withdrawal symptoms and psychiatric symptoms (depression, suicidality, psychotic symptoms and hostility). Adverse events are monitored at each weekly assessment. Tolerability is assessed using the Treatment Satisfaction Questionnaire for Medication.DiscussionThe N-ICE trial is the first clinical trial to assess whether NAC can reduce methamphetamine use. This trial will improve our understanding of the potential utility of NAC in managing methamphetamine dependence and clinically related outcomes. If found to be effective, take-home NAC could be a potentially scalable and affordable pharmacotherapy option for treating methamphetamine dependence.Trial registrationAustralian and New Zealand Clinical Trials Registry, ACTRN12618000366257. Registered on 29 May 2018.

A randomised controlled trial of multimodal physiotherapy versus advice for recent onset, painful cervical radiculopathy \u2013 the PACeR trial protocol

BackgroundA research gap exists for optimal management of cervical radiculopathy in the first 12 weeks and short term natural history of the condition is somewhat unclear, although thought to be favourable. The primary aim of this assessor blinded, superiority, 2 parallel group randomised controlled trial is to investigate the effects of a 4 week physiotherapy programme (6–8 sessions) of manual therapy, exercise and upper limb neural unloading tape, compared to a control of weekly phone advice; on disability, pain and selected biopsychosocial measures, in acute and sub-acute cervical radiculopathy patients. A secondary aim is to identify whether any baseline variables, symptom duration or group allocation can predict outcome.MethodsParticipants are recruited from GP referrals in an urban setting, from a neurosurgery non-urgent waiting list and from self-referral through Facebook advertising. Eligible participants (n = 64) are diagnosed with radiculopathy based on a clinical prediction rule and must have symptoms of unilateral, single level, radiculopathy for between 2 and 12 weeks, without having yet received physiotherapy. Random 1:1 group allocation (using variable block sizes), allocation concealment, blinded assessment and intention to treat analysis are being employed. Treatment is provided by clinical specialist physiotherapists in primary and secondary care settings. Outcomes are measured at baseline, 4 (primary endpoint) and 12 weeks. Participants’ report of pain, disability and their rating of recovery is also recorded by telephone interview at 6 months. Statistical analysis of between group differences will be performed with ANOVAs and MANOVAs, and multivariable regression analysis will be undertaken to explore predictor variables. Ethical approval for this study has been received from the Beaumont Hospital and Irish College of General Practitioners Research Ethics Committees. The trial is registered at ClinicalTrials.gov (NCT02449200).DiscussionAn internal pilot study to test retention and recruitment strategies led to trial expansion and this is now a multi centre trial involving 5 clinical sites.Trial registrationNCT02449200. Registered 20/05/15.

High‐throughput and flexible ASIC implementations of SIMON and SPECK lightweight block ciphers

SummaryIn this paper, high‐throughput and flexible hardware implementations of the SIMON and SPECK lightweight block ciphers are presented. The most complex block in the SPECK algorithm is addition modulo 2n, where n is word size (half of the input data). In the proposed structure of modular adder, we used the Sklansky adder, which is an efficient parallel prefix adder with low critical path delay and suitable hardware resources. In the SIMON block cipher, to reduce critical path delay, we use a tree structure for implementation of XOR operations. In addition, we proposed flexible structures that can perform various configurations of the SIMON and SPECK ciphers to support variable key sizes (128, 144, 192, and 256 bits) and block sizes (64, 96, and 128 bits). Therefore, the flexible architectures provide versatile implementations with adaptive security level and the ability of encryption of longer messages based on variable key size and variable block size. Implementation results of the proposed structures in 180 nm CMOS technology for different key and block sizes are achieved. The results show that the proposed structures have better critical path delay compared with other's related works.

BCH Code Error Detection and Correction for Variable Block Length and Message Length using VHDL

BCH Code Error Detection and Correction for Variable Block Length and Message Length using VHDL

A Variable Block Insertion Heuristic for Solving Permutation Flow Shop Scheduling Problem with Makespan Criterion

In this paper, we propose a variable block insertion heuristic (VBIH) algorithm to solve the permutation flow shop scheduling problem (PFSP). The VBIH algorithm removes a block of jobs from the current solution. It applies an insertion local search to the partial solution. Then, it inserts the block into all possible positions in the partial solution sequentially. It chooses the best one amongst those solutions from block insertion moves. Finally, again an insertion local search is applied to the complete solution. If the new solution obtained is better than the current solution, it replaces the current solution with the new one. As long as it improves, it retains the same block size. Otherwise, the block size is incremented by one and a simulated annealing-based acceptance criterion is employed to accept the new solution in order to escape from local minima. This process is repeated until the block size reaches its maximum size. To verify the computational results, mixed integer programming (MIP) and constraint programming (CP) models are developed and solved using very recent small VRF benchmark suite. Optimal solutions are found for 108 out of 240 instances. Extensive computational results on the VRF large benchmark suite show that the proposed algorithm outperforms two variants of the iterated greedy algorithm. 236 out of 240 instances of large VRF benchmark suite are further improved for the first time in this paper. Ultimately, we run Taillard’s benchmark suite and compare the algorithms. In addition to the above, three instances of Taillard’s benchmark suite are also further improved for the first time in this paper since 1993.

Protocol: randomised trial to compare nasoduodenal tube and nasogastric tube feeding in infants with bronchiolitis on high-flow nasal cannula; Bronchiolitis and High-flow nasal cannula with Enteral Tube feeding Randomised (BHETR) trial

IntroductionHigh-flow nasal cannula (HFNC) is a non-invasive form of respiratory support used increasingly in bronchiolitis. HFNC provides a variable amount of positive pressure similar to continuous positive airway pressure (CPAP)....

Individualised nutritional support in medical inpatients at nutritional risk: a randomised clinical trial

Guidelines recommend the use of nutritional support during hospital stays for medical patients (patients not critically ill and not undergoing surgical procedures) at risk of malnutrition. However, the supporting evidence for this recommendation is insufficient, and there is growing concern about the possible negative effects of nutritional therapy during acute illness on recovery and clinical outcomes. Our aim was thus to test the hypothesis that protocol-guided individualised nutritional support to reach protein and caloric goals reduces the risk of adverse clinical outcomes in medical inpatients at nutritional risk. The Effect of early nutritional support on Frailty, Functional Outcomes, and Recovery of malnourished medical inpatients Trial (EFFORT) is a pragmatic, investigator-initiated, open-label, multicentre study. We recruited medical patients at nutritional risk (nutritional risk screening 2002 [NRS 2002] score ≥3 points) and with an expected length of hospital stay of more than 4 days from eight Swiss hospitals. These participants were randomly assigned (1:1) to receive either protocol-guided individualised nutritional support to reach protein and caloric goals (intervention group) or standard hospital food (control group). Randomisation was done with variable block sizes and stratification according to study site and severity of malnutrition using an interactive web-response system. In the intervention group, individualised nutritional support goals were defined by specialist dietitians and nutritional support was initiated no later than 48 h after admission. Patients in the control group received no dietary consultation. The composite primary endpoint was any adverse clinical outcome defined as all-cause mortality, admission to intensive care, non-elective hospital readmission, major complications, and decline in functional status at 30 days, and it was measured in all randomised patients who completed the trial. This trial is registered with ClinicalTrials.gov, number NCT02517476. 5015 patients were screened, and 2088 were recruited and monitored between April 1, 2014, and Feb 28, 2018. 1050 patients were assigned to the intervention group and 1038 to the control group. 60 patients withdrew consent during the course of the trial (35 in the intervention group and 25 in the control group). During the hospital stay, caloric goals were reached in 800 (79%) and protein goals in 770 (76%) of 1015 patients in the intervention group. By 30 days, 232 (23%) patients in the intervention group experienced an adverse clinical outcome, compared with 272 (27%) of 1013 patients in the control group (adjusted odds ratio [OR] 0·79 [95% CI 0·64-0·97], p=0·023). By day 30, 73 [7%] patients had died in the intervention group compared with 100 [10%] patients in the control group (adjusted OR 0·65 [0·47-0·91], p=0·011). There was no difference in the proportion of patients who experienced side-effects from nutritional support between the intervention and the control group (162 [16%] vs 145 [14%], adjusted OR 1·16 [0·90-1·51], p=0·26). In medical inpatients at nutritional risk, the use of individualised nutritional support during the hospital stay improved important clinical outcomes, including survival, compared with standard hospital food. These findings strongly support the concept of systematically screening medical inpatients on hospital admission regarding nutritional risk, independent of their medical condition, followed by a nutritional assessment and introduction of individualised nutritional support in patients at risk. The Swiss National Science Foundation and the Research Council of the Kantonsspital Aarau, Switzerland.

Analysis of Airgap Field Modulation Principle of Simple Salient Poles

This paper models a huge family of electrical machines featuring simple salient poles in a unified way based on the general airgap field modulation theory. The modulation principle is analyzed by introducing the magnetomotive force (MMF) modulation operator, which characterizes the influence of a variable reluctance block on the primitive magnetizing MMF distribution established by field winding. Popular machine topologies are investigated in detail from the perspective of an airgap field modulation mechanism. The iron core magnetic potential drop due to the finite slot opening depth and the impact of iron saturation on the parameters are considered by proper theoretical indication. In addition, the modulation effect of salient poles highly depends on the slot-opening-width-to-pole-pitch ratio ϵ . The effect can be neglected when ϵ ϵ = 0.5. It is also found that mainly three different harmonics parts modulated by salient poles contribute to airgap flux density and torque production. Straightforward relations between the frequency-domain or amplitude information of performances indexes and topological parameters can be obtained obviously by certain analytical expressions without heavy finite-element analysis (FEA). Analytical results are verified by two-dimensional FEA and experiments measurements.

Photolysis of a Caged, Fast-Equilibrating Glutamate Receptor Antagonist, Mni-Caged-Gamma-D-Glutamyl-Glycine, to Investigate Transmitter Dynamics and Receptor Properties at Glutamatergic Synapses

Fast uncaging of low affinity competitive receptor antagonists can in principle measure the timing and concentration dependence of transmitter action at receptors during synaptic transmission, distinguishing fast, independent contacts from diffuse multisite transmission. MNI-caged γ-D-glutamyl-glycine combines the fast photolysis and hydrolytic stability of nitroindoline cages with the fast-equilibrating competitive glutamate receptor antagonist γ-DGG. Its suitability as a caged probe was tested at climbing fiber-Purkinje cell (CF-PC) synapses. MNI-caged γ-DGG applied at 5 mM permitted release of up to 2 mM γ-DGG in 1 ms in wide-field flashlamp photolysis. In steady-state conditions, photoreleased γ-DGG at 1 mM inhibited the CF first and second paired EPSCs by 30% and 60% respectively, similar to bath applied γ-DGG. Photolysis of the L-isomer MNI-caged γ-L-glutamyl-glycine was ineffective. The time-course of receptor activation was investigated by photolysis of MNI-caged-γ-DGG at defined intervals following CF stimulation in the second EPSC of a paired pulse protocol. Photolysis prior to the stimulus and up to 3 ms after showed strong inhibition similar to steady-state; photolysis at 4 ms post-stimulus produced weaker and highly variable block, suggesting transmitter-receptor interaction occurs mainly in the interval 3-4 ms post-stimulus. This indicates an unexpected delay between stimulus and release. The data show a late component of inhibition when γ-DGG was released at 5 ms or 6 ms post stimulus, near the peak of the CF-PC EPSC, or after the peak at 10 ms. This indicates competition for receptor activation during the late phase of the EPSC, due to delayed transmitter release or persistence of glutamate in the synapse. MNI-caged-γ-DGG appears suitable as a synaptic probe at high concentration, and its photolysis can resolve timing and extent of receptor activation to investigate synaptic independence.