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The ecological task analysis approach to teaching physical education provides a framework for the processes of assessment and instruction that differs from the traditional teacher-directed methods. The article discusses the model's advantages and describes how teachers can implement the model. (SM)

Introduction: Previous studies have largely explored the microbial composition and pathogenesis of pregnancy gingivitis. However, the patterns of microbial colonization during pregnancy in the absence of pregnancy gingivitis have rarely been studied. Characterization of the oral microbiome in pregnant women with healthy gingiva is an important initial step in understanding the role of the microbiome in progression to pregnancy gingivitis. Objectives: In this study, we compared the oral microbiome of pregnant women without gingivitis (healthy pregnancy) with pregnant women having gingivitis and nonpregnant healthy women to understand how pregnancy modifies the oral microbiome and induces progression to pregnancy gingivitis. Methods: Subgingival plaque samples were collected from Chinese pregnant women with gingivitis (n = 10), healthy pregnant women (n = 10), and nonpregnant healthy women (n = 10). The Illumina MiSeq platform was used to perform 16S rRNA gene sequencing targeting the V4 region. Results: The alpha and beta diversity was significantly different between pregnant and nonpregnant women, but minimal differences were observed between pregnant women with and without gingivitis. Interestingly, the oral bacterial community showed higher abundance of pathogenic taxa during healthy pregnancy as compared with nonpregnant women despite similar gingival and plaque index scores. However, when compared with overt pregnancy gingivitis, pathogenic taxa were less abundant during healthy pregnancy. PICRUSt analysis (phylogenetic investigation of communities by reconstruction of unobserved states) also suggested no difference in the functional capabilities of the microbiome during pregnancy, irrespective of gingival disease status. However, metabolic pathways related to amino acid metabolism were significantly increased in healthy pregnant women as compared with nonpregnant women. Conclusion: The presence of pathogenic taxa in healthy pregnancy and pre

BACKGROUND Subclinical leaflet thickening and reduced leaflet motion of bioprosthetic aortic valves have been documented by four-dimensional computed tomography (CT). Whether anticoagulation can reduce these phenomena after transcatheter aortic-valve replacement (TAVR) is not known. METHODS In a substudy of a large randomized trial, we randomly assigned patients who had undergone successful TAVR and who did not have an indication for long-term anticoagulation to a rivaroxaban-based antithrombotic strategy (rivaroxaban [10 mg] plus aspirin [75 to 100 mg] once daily) or an antiplatelet-based strategy (clopidogrel [75 mg] plus aspirin [75 to 100 mg] once daily). Patients underwent evaluation by four-dimensional CT at a mean (±SD) of 90±15 days after randomization. The primary end point was the percentage of patients with at least one prosthetic valve leaflet with grade 3 or higher motion reduction (i.e., involving >50% of the leaflet). Leaflet thickening was also assessed. RESULTS A total of 231 patients were enrolled. At least one prosthetic valve leaflet with grade 3 or higher motion reduction was found in 2 of 97 patients (2.1%) who had scans that could be evaluated in the rivaroxaban group, as compared with 11 of 101 (10.9%) in the antiplatelet group (difference, -8.8 percentage points; 95% confidence interval [CI], -16.5 to -1.9; P=0.01). Thickening of at least one leaflet was observed in 12 of 97 patients (12.4%) in the rivaroxaban group and in 33 of 102 (32.4%) in the antiplatelet group (difference, -20.0 percentage points; 95% CI, -30.9 to -8.5). In the main trial, the risk of death or thromboembolic events and the risk of life-threatening, disabling, or major bleeding were higher with rivaroxaban (hazard ratios of 1.35 and 1.50, respectively). CONCLUSIONS In a substudy of a trial involving patients without an indication for long-term anticoagulation who had undergone successful TAVR, a rivaroxaban-based antithrombotic strategy was more effective than an ant

In the past decade, there has been a tremendous increase in studies on the link between oral microbiome and systemic diseases. However, variations in study design and confounding variables across studies often lead to inconsistent observations. In this narrative review, we have discussed the potential influence of study design and confounding variables on the current sequencing-based oral microbiome-systemic disease link studies. The current limitations of oral microbiome-systemic link studies on type 2 diabetes mellitus, rheumatoid arthritis, pregnancy, atherosclerosis, and pancreatic cancer are discussed in this review, followed by our perspective on how artificial intelligence (AI), particularly machine learning and deep learning approaches, can be employed for predicting systemic disease and host metadata from the oral microbiome. The application of AI for predicting systemic disease as well as host metadata requires the establishment of a global database repository with microbiome sequences and annotated host metadata. However, this task requires collective efforts from researchers working in the field of oral microbiome to establish more comprehensive datasets with appropriate host metadata. Development of AI-based models by incorporating consistent host metadata will allow prediction of systemic diseases with higher accuracies, bringing considerable clinical benefits.

Additive manufacturing (AM), often termed 3D printing, has recently emerged as a mainstream means of producing metallic components from a variety of metallic alloys. The numerous benefits of AM include net shape manufacturing, efficient use of material, suitability to low volume production runs, and the ability to explore alloy compositions not previously accessible to conventional casting. The process of AM, which is nominally performed using laser (or electron) based local melting, has a definitive role in the resultant alloy microstructure. Herein, the corrosion of alloys prepared by AM using laser and electron-based methods, relating the corrosion performance to the microstructural features influenced by AM processing, are reviewed. Such features include unique porosity, grain structures, dislocation networks, residual stress, solute segregation, and surface roughness. Correlations between reported results and deficiencies in present understanding are highlighted.

A novel approach to the direct measurement of the plasma potential in magnetized plasmas, using the so-called "ball-pen probe", was recently tested in the CASTOR tokamak. Comparison with the standard technique of plasma potential measurement using the emissive probe is reported. It is found that the plasma potential determined by the emissive probe is systematically lower than that measured by the ball-pen probe. The difference is of the of the of kT e/e. A possible reason of this difference is the space charge occurring in the proximity of the emissive probe.

We have developed tunnel probes for localized measurements of the electron and ion temperature in the edge plasma region of smaller tokamaks and stellarators. A normal tunnel probe for Te measurements consists of a metallic tunnel of 5 mm diameter and 5 mm length, with the axis parallel to the magnetic field. One side is open, the other side is closed by a metallic backplate, isolated from the tunnel. If both electrodes are biased negatively, ions flow into the office, and their current is distributed between the tunnel and the backplate. The ratio of the two ion currents is a function of T e. With an additional diaphragm in front of the orifice, the probe becomes ion sensitive, since the electrons are prevented from the tunnel because of their smaller gyroradius, but ions can still reach it. In this way, the perpendicular ion temperature can be derived. By segmenting the tunnel axially into two parts, also an approximate measure for the parallel ion temperature can be found.

Localised ion temperature measurements can only be performed with special electric probes where the electron component of the current is kept off from the collector. In a strong magnetic field the effect can be utilised that the electron gyro-radius is much smaller than that of the ions. This method was developed by Katsumata and Okazaki (Japan J. Appl. Phys. 6, 123 (1967)). We have used a so-called tunnel probe (which consists of a conductive tunnel, terminated by an isolated back plate) by adding a diaphragm in front. Thereby the tunnel is prevented from incident electrons at any potential of both electrodes. By sweeping the potential across the tunnel, the perpendicular ion temperature can be inferred. By segmenting the tunnel axially in two parts also the parallel ion temperature can be determined. When the electrodes are biased to ion saturation, the ratio between the ion currents, which reach the first and the second segment, respectively, is a measure for the parallel ion temperature. The dependence of the ratio of the currents has to be determined by a PIC simulation.

A novel probe and approach to the direct measurements of the plasma potential in a strong magnetic field is suggested. The principle of this method is to reduce the electron saturation current to the same magnitude as that of the ion saturation current. In this case, the floating potential of the probe becomes identical to the plasma potential. This goal is attained by a shield, which screens off an adjustable part of the electron current from the probe collector due to the much smaller gyro-radius of the electrons. First systematic measurements have been performed in the CASTOR tokamak.

The plasma potential and its fluctuations were measured by electron emissive probes in the edge plasma regions of tokamaks. Fusion experiments were conducted on ISTTOK tokamak, Portugal and CASTOR tokamak, Czech Republic. In ISTTOK, three emissive probes were used. In CASTOR, two emissive probes were used which could be radially shifted. The advantage of a sufficiently emissive probe is that it allows plasma potential and its fluctuations to be measured directly.

Experiments in the tokamaks TEXTOR, CASTOR, T-10 and ISTTOK, as well as in the reversed field pinch RFX have provided new and complementary evidence on the physics of the universal mechanism of E × B velocity shear stabilization of turbulence, concomitant transport barrier formation and radial conductivity by using various edge biasing techniques. In TEXTOR the causality between transport reduction and induced electric fields in the edge has been for the first time clearly demonstrated. The high electric field gradients have been identified as the cause for the quenching of turbulent cells. A quantitative analysis of the measured transport reduction is in good agreement with theoretical predictions. The scaling of plasma turbulence suppression with velocity shear has been established, revealing the density-potential cross-phase as a key element. Reduction in poloidal electric field, temperature, and density fluctuations across the shear layer lead to a reduction of the anomalous conducted and convected heat fluxes resulting in an energy transport barrier that is measured directly. In CASTOR the biasing electrode is placed at the separatrix in a non-intrusive configuration which has demonstrated strongly sheared electric fields and consequent improvement of the global particle confinement, as predicted by theory. The impact of sheared E × B flow on edge turbulent structures has been measured directly using a comprehensive set of electrostatic probe arrays as well as emissive probes. Measurements with a full poloidal Langmuir probe array have revealed quasi-coherent electrostatic waves in the SOL with a dominant mode number equal to the edge safety factor. In T-10 edge biasing is clearly improving the global performance of ECR heated discharges. Reflectometry and heavy ion beam probe measurements show the existence of a narrow plasma layer with strong suppression of turbulence. On ISTTOK, the influence of alternating positive and negative electrode and (non-intrusive)

An emissive probe has been used in the edge region of the CASTOR tokamak in order to test the possibility of direct measurements of the plasma potential. The difference between the floating potential of a cold probe and that of an emissive probe has been found to be approximately 1.3 times the electron temperature, which is less than predicted by the probe theory. Several possible reasons to explain this discrepancy are offered, such as secondary electron emission, uncertainties in the ion temperature, different collecting areas for electrons and ions, etc. The possible impact of a space charge formed by the emitted electrons is also discussed.

A new probe head, composed of two electro-emissive probes and two Langmuir probes has been designed to measure edge fluctuations in the CASTOR tokamak. In this contribution, only one Langmuir and one electron-emissive probe are used to measure the temperature and potential fluctuations and the phase angle between them.

Experiments in the tokamaks TEXTOR, CASTOR, T-10 and ISTTOK, as well as in the reversed field pinch RFX have provided new and complementary evidence on the physics of the universal mechanism of E x B velocity shear stabilization of turbulence, concomitant transport barrier formation and radial conductivity by using various edge biasing techniques. In TEXTOR the causality between transport reduction and induced electric fields in the edge has been for the first time clearly demonstrated. The high electric field gradients have been identified as the cause for the quenching of turbulent cells. A quantitative analysis of the measured transport reduction is in good agreement with theoretical predictions. The scaling of plasma turbulence suppression with velocity shear has been established, revealing the density-potential cross-phase as a key element. Reduction in poloidal electric field, temperature, and density fluctuations across the shear layer lead to a reduction of the anomalous conducted and convected heat fluxes resulting in an energy transport barrier that is measured directly. In CASTOR the biasing electrode is placed at the separatrix in a non-intrusive configuration which has demonstrated strongly sheared electric fields and consequent improvement of the global particle confinement, as predicted by theory. The impact of sheared E x B flow on edge turbulent structures has been measured directly using a comprehensive set of electrostatic probe arrays as well as emissive probes. Measurements with a full poloidal Langmuir probe array have revealed quasi-coherent electrostatic waves in the SOL with a dominant mode number equal to the edge safety factor. In T-10 edge biasing is clearly improving the global performance of ECR heated discharges. Reflectometry and heavy ion beam probe measurements show the existence of a narrow plasma layer with strong suppression of turbulence. On ISTTOK, the influence of alternating positive and negative electrode and (non-intrusive), QC 20100525