Magnetic configuration scans during divertor operation of Wendelstein 7-X

Wendelstein 7-X (Greifswald, Germany) is an advanced stellarator, which uses the modular coil concept to realize a magnetic configuration optimized for fusion-relevant plasma properties. The magnet system of the machine allows a variation of the rotational transform (iota) at the boundary. In the latest Wendelstein 7-X operational phase a dedicated configuration scan has been performed varying the rotational transform between magnetic configurations with iota=5/4 and iota=5/5 at the boundary. This paper presents an overview of the experiments and of the main results with respect to confinement and stability. The main observation is an increase of the plasma energy in several intermediate configurations of the scan when the 5/5-islands are close to the plasma boundary but still inside the last-closed-flux-surface. In addition, these configurations showed marked MHD-activity with a crashing behavior related to the 5/5-islands. The corresponding mode amplitude was correlated with the size of the internal 5/5 islands.

Judging the judges: evaluating the accuracy and national bias of international gymnastics judges

We design, describe and implement a statistical engine to analyze the performance of gymnastics judges with three objectives: (1) provide constructive feedback to judges, executive committees and national federations; (2) assign the best judges to the most important competitions; (3) detect bias and persistent misjudging. Judging a gymnastics routine is a random process, and we model this process using heteroscedastic random variables. The developed marking score scales the difference between the mark of a judge and the true performance level of a gymnast as a function of the intrinsic judging error variability estimated from historical data for each apparatus. This dependence between judging variability and performance quality has never been properly studied. We leverage the intrinsic judging error variability and the marking score to detect outlier marks and study the national bias of judges favoring athletes of the same nationality. We also study ranking scores assessing to what extent judges rate gymnasts in the correct order. Our main observation is that there are significant differences between the best and worst judges, both in terms of accuracy and national bias. The insights from this work have led to recommendations and rule changes at the Fédération Internationale de Gymnastique.

COVID-19 Vaccination in Patients with Myasthenia Gravis: A Single-Center Case Series

In this study, we report the safety of coronavirus disease 2019 (COVID-19) vaccine in patients with myasthenia gravis (MG). Patients who were vaccinated against COVID-19 were included. Demographics, clinical characteristics, medications, and vaccination information were collected. The main observation outcome is the worsening of MG symptoms within 4 weeks following COVID-19 vaccination. A total of 22 patients with MG vaccinated for COVID-19 were included. Ten (45.5%) patients had ocular MG (OMG), and 12 (55.5%) patients had generalized MG (GMG). Six (27.3%) patients were female, and the mean (SD) onset age was 45.4 (11.8) years. Nineteen (86.4%) patients were seropositive for acetylcholine receptors (AChR) antibody. Seven (31.8%) patients underwent thymectomy, and four of them confirmed thymoma pathologically. Twenty-one patients were administrated with inactivated vaccines, and the remaining one was administrated with recombinant subunit vaccine. Twenty (90.9%) patients did not present MG symptom worsening within 4 weeks of COVID-19 vaccination, and two (9.1%) patients reported slight symptom worsening but resolved quickly within a few days. Our findings suggest inactivated COVID-19 vaccines might be safe in MG patients with Myasthenia Gravis Foundation of America (MGFA) classification I to II, supporting the recommendation to promote vaccination for MG patients during the still expanding COVID-19 pandemic.

Case Report: In Situ Expression of a Proliferation-Inducing Ligand in Neuromyelitis Optica

A proliferation inducing ligand (APRIL) mediates a key role in the generation and survival of antibody-inducing plasmocytes. Based on this, APRIL has been targeted in autoimmune diseases including multiple sclerosis (MS) and optic neuritis (ON). In MS lesions, APRIL has a new cellular target, the reactive astrocyte and mediates an immunosuppressive activity. Here, we analyzed APRIL expression in a case of neuromyelitis optica (NMO), another autoimmune neurodegenerative disease, showing selective aquaporin-4 depletion in the spinal cord, complement deposition and infiltration of polymorphonuclear cells. We analyzed by immunohistochemistry the presence of APRIL-producing cells, plasmocytes, astrocytes and the localization of secreted APRIL in a lesion from NMO. Plasmocytes were present close to APRIL-producing cells in meninges. However, our main observation was that APRIL targets reactive astrocytes in this lesion of NMO similarly to MS.

Contrastive Model Invertion for Data-Free Knolwedge Distillation

Model inversion, whose goal is to recover training data from a pre-trained model, has been recently proved feasible. However, existing inversion methods usually suffer from the mode collapse problem, where the synthesized instances are highly similar to each other and thus show limited effectiveness for downstream tasks, such as knowledge distillation. In this paper, we propose Contrastive Model Inversion (CMI), where the data diversity is explicitly modeled as an optimizable objective, to alleviate the mode collapse issue. Our main observation is that, under the constraint of the same amount of data, higher data diversity usually indicates stronger instance discrimination. To this end, we introduce in CMI a contrastive learning objective that encourages the synthesizing instances to be distinguishable from the already synthesized ones in previous batches. Experiments of pre-trained models on CIFAR-10, CIFAR-100, and Tiny-ImageNet demonstrate that CMI not only generates more visually plausible instances than the state of the arts, but also achieves significantly superior performance when the generated data are used for knowledge distillation. Code is available at https://github.com/zju-vipa/DataFree.

Characterization of GAGG Doped with Extremely Low Levels of Chromium and Exhibiting Exceptional Intensity of Emission in NIR Region

Cerium and chromium co-doped gadolinium aluminum gallium garnets were prepared using sol-gel technique. These compounds potentially can be applied for NIR-LED construction, horticulture and theranostics. Additionally, magnesium and calcium ions were also incorporated into the structure. X-ray diffraction data analysis confirmed the all-cubic symmetry with an Ia-3d space group, which is appropriate for garnet-type materials. From the characterization of the luminescence properties, it was confirmed that both chromium and cerium emissions could be incorporated. Cerium luminescence was detected under 450 nm excitation, while for chromium emission, 270 nm excitation was used. The emission of chromium ions was exceptionally intense, although it was determined that these compounds are doped only by parts per million of Cr3+ ions. Typically, the emission maxima of chromium ions are located around 650–750 nm in garnet systems. However, in this case, the emission maximum for chromium is measured to be around 790 nm, caused by re-absorption of Cr3+ ions. The main observation of this study is that the switchable emission wavelength in a compound of single phase was obtained, despite the fact that doping with Cr ions was performed in ppm level, causing an intense emission in NIR region.

Preloading Model on Soft Soil with Inclusion Thermal Induction Vertical and Incline Types

Soft clay has a relatively low subgrade bearing capacity. The aim is to obtain physical values, mineralogy, mechanical strength values, values for reduction. The research method used is preloading in a test tube measuring 50×70×150 cm. Each cycle of preloading and thermal induction used a fixed load of 0.015 kg/cm². Thermal induction is given vertically and obliquely with temperature variations of 100, 200, 300, and 400 °C. The main observation point is a distance of 15 cm from the center of the induction. At 400 °C inclined induction, the water content is 17.36% (from the initial water content of 59.07%), the soil cohesion is 21.75. kN/m², the value of unconfined compressive strength is 67.72 kN/m², the highest modulus of elasticity is 4593 kN/m2, and the decrease is 5.13 cm. XRD, SEM, EDS results before heating showed mineralogy 0 (65.06%), Ca (13.30%), Na (3.64%), Mg (2.15%), Al (6.63%), Si (8.52%), Sn (0.70%) and did not change significantly after heating at 400 °C. The results after heating included 0 (58.39%), Ca (14.09%), Na (0.72%), Mg (1.16%), Al (6.63%), Si (14.72%), Sn (2.54%). The novelty obtained is to change very soft conditions became medium conditions. Doi: 10.28991/cej-2021-03091705 Full Text: PDF

Influence of Active Flow Control on Blunt-Edged VFE-2 Delta Wing model

This paper highlights the flow topology above blunt-edged delta wing of VFE-2 configuration when an active flow control technique called ‘blower’ is applied in the leading edge of the wing. The flow topology above blunt-edged delta wing is very complex, disorganised and unresolved compared to sharp-edged wing. For the sharp leading-edged wing, the onset of the primary vortex is fixed at the apex of the wing and develops along the entire wing towards the trailing edge. However, the onset of the primary vortex is no longer fixed at the apex of the wing for the blunt-edged case. The onset of the primary vortex develops at a certain chord-wise position and it moved upstream or downstream depending on Reynolds number, angle of attack, Mach number and the leading-edge bluntness. An active flow control namely ‘blower’ technique has been applied in the leading edge of the wing in order to investigate the upstream/downstream progression of the primary vortex. This research has been carried out in order to determine either the flow on blunt-edged delta wing would behave as the flow above sharp-edged delta wing if any active flow control is applied. The experiments were performed at Reynolds number of 0.5×106, 1.0×106 and 2.0×106 corresponding to 9 m/s, 18 m/s and 36 m/s in UTM Low Speed wind Tunnel based on the mean aerodynamic chord of the wing. The results obtained from this research have shown that the blower technique has significant effects on the flow topology above blunt-edged delta wing. The main observation from this study was that the primary vortex has been shifted 20% upstream when the blower technique is applied. Another main observation was the ability of this flow control to delay the formation of the vortex breakdown.

Impact of COVID-19 on Market Risk: Appraisal with Value-at-risk Models

COVID-19 has traumatised the whole world in every aspect ranging from normal day-to-day activities to complete halt of the economies. This piece of work attempted to examine the response of the stock markets to the outbreak of COVID-9 by considering stock indices of five leading countries and comparing the risk with other periods of crisis viz. global financial crisis of 2007-2008 and stock market fluctuation in 1992. Both negative and positive fluctuation are examined, however special emphasis is placed on downside risk. The risk is measured using Value-at-Risk models with different distributional assumptions. The main observation of the study points towards gravity of this deadly virus as the volatility in the stock markets of all the countries is higher even compared to the global crisis of 2008 except China which is quite absurd. On the other hand, global markets are found to be highly correlated in the COVID-19 period. However, investors are also found to be reacting positively when favourable news is transmitted. The findings of this paper will help the investors in understanding the short-run dynamics of the stock markets and use such information in future for investment in similar circumstances.

HUBUNGAN ANTARA PENGENDALIAN DIRI DENGAN PRESTASI BELAJAR SISWA SMKN 1 SUMBAWA BESAR

Abstrac: Self-control closely related to person's condition emotional. Individuals who are good at emotions managing themselves control well, because they express emotions properly, appropriately and correctly. Self-control skill individuals have controlling and behavior managing, cognitive, and impulses control achieving individual satisfaction and desires for certain goals, there are aspects of self, behavior, cognitive and satisfaction controlling’s. Learning achievement, the result obtained after carrying out a series of processes learning, which be shown quantitatively by the value or number given the educator to learning subject form of behavior after carrying out the previous learning. The problem examined this research There a Relationship Self-Control with Student Achievement of SMKN 1 Sumbawa Besar? The find out research objective is Relationship Self-Control with Student Achievement of SMKN 1 Sumbawa Besar. The total population is 1222 students and sample of 10% or 127 students. Methods data collection using the questionnaire as main, observation, documentation, interview method’s. Data analysis using the formula product moment. Based on the results of data analysis with a significant level of 5%, the results of the research that rxy value is greater than the r value of the product moment (rxy 0.786> r product moment 0.195) this fact shows rxy value obtained from the results of data analysis can be concluded that: There a Relationship Self-Control with Student Achievement of SMKN 1 Sumbawa Besar. This research it is stated that significant.Keywords: Self-Control, Achievement Learning