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关键词： CIRNO C2008   Mutation   Gamma-rays   LD50   Morphology   Agronomic trait  

摘要： Wheat var: CIRNO C2008 was irradiated with gamma rays at 100, 200, and 300 Gy. The irradiated plants obtained at 300 Gy (M-1) showed a significant reduction (compared to M-0 plants) in germination (i.e. 3.8% at day 5), survival percentage (48%), and plant height (63.3%). Thus, the Probit analysis showed an LD50 of 287.80 Gy. Besides, these irradiated plants, in the field, showed a significant increase (compared to M-0 plants) in days to spike initiation (16 days), and maturation (14 days). On the other hand, in the field, fourteen chlorophyll mutants were found (at a different frequency) in the M-2 generation, such as Albina, Anthocyanin, Chlorin, Maculata, Tigrina, Striata, Viridis, Viridoalbina, Alboviridis, Xantha, Xanthviridis, Xanthalba, Viridoxantha, and Orange stem. In addition, mutants with changes in agronomic and morphological traits were observed. This nuclear technique is an alternative to obtain promising mutant lines that can be used directly as a variety and/or as parental to transfer these traits to other varieties.

关键词： Surplus of dentists   Uneven regional distribution   Postgraduate year training program for dentists  

摘要： Background/purpose: In Taiwan, there are three major dentist occupation problems: a surplus of dentists, an uneven regional distribution of dentists, and a concentration of dentists in the metropolitan areas. The purpose of this study was to evaluate the distributions of the population and dentists in each city or county in 2001, 2010 and 2019 to further analyze the changes of regional distributions of dentists 9 years after the implementation of postgraduate year training program for dentists (PGYD) in 2010 in Taiwan. Materials and methods: This study collected the data of population, the number of dentists in each city or county in 2001, 2010 and 2019, and the numbers of dentists and dental institutions from 2001 to 2019 for evaluating the changes of regional distributions of dentists 9 years after the PGYD implementation in Taiwan. Results: Nine years after the PGYD implementation, the uneven distribution of dentists persisted. The number of dentists still increased and dentists were more concentrated in municipalities than in non-municipalities in Taiwan. Moreover, the number of dental institutions increased slowly, but dental institutions tended to become larger. Conclusion: Because the PGYD system is not mandatory, dentists choose their practice locations as driven by the market factors. The increase in the average number of dentists in dental institutions is also driven by the market factors. The market-driven movement of dentists to the people-concentrated municipalities finally persist the imbalance of dentist distribution in Taiwan. This situation also enables the development of large-scale dental institutions in municipalities in Taiwan. (C) 2020 Association for Dental Sciences of the Republic of China. Publishing services by Elsevier B.V.

关键词： Amniotic fluid embolism   Post-mortem diagnosis   Immunohistochemistry   Cytokeratins   CD31  

摘要： Amniotic fluid embolism (AFE) is a rare cause of unexpected late maternal gestational death. The forensic post-mortem diagnosis is rendered upon the histological recognition of fetal "foreign" material inside maternal lung vasculature. The authors propose a double immunohistochemical (anti-CD31 plus anti-cytokeratin AE1/AE3) stain in order to assess accurate amniotic fluid pulmonary embolic burden in a highly reproducible fashion based on the fact that such technique allows to detect an impressive amount of scales within lung vasculature, thereby offering further evidence that pulmonary embolic obstructive microangiopathy, rather than anaphylactoid reaction, is major determinant in AFE-related death.

关键词： Atlantoaxial dislocation   Atlantoaxial arthrodesis   Atlantoaxial fusion   C2 pedicle screw   C2 partial transpedicular screw  

摘要： Objective: Although the C2 pedicle screw (C2PS) is currently the most biomechanically robust option for C2 fixation, the high-riding vertebral artery (HRVA) precludes safe C2PS placement. However, unintentional partial C2 pedicle perforation and vertebral foramen violation due to C2PS placement without neurovascular complications occurred frequently in clinic. Therefore, we have attempted to apply C2 partial transpedicular screw (C2PTS) in patients with HRVA with satisfactory preliminary outcomes. The aim of the present study is to introduce the C2PTS technique and report the preliminary radiological and clinical outcomes of application of C2PTS. Patients and methods: The data of 15 patients with atlantoaxial dislocation underwent atlantoaxial arthrodesis with posterior screw-rod construct were retrospectively reviewed. All patients had unilateral or bilateral HRVA that precluded safe C2PS placement and C2PTS was used as an alternative. In this technique, a Penfield dissector was used to properly mobilize the HRVA inferiorly to preclude vertebral artery injury and pave the way for C2PTS placement. The C2PTS travelled under the superior border of the isthmus and toward the ipsilateral atlantoaxial articulation. The implant position and atlantoaxial reduction were evaluated using computed tomography (CT) scans and vertebral artery (VA) was assessed using CT angiography postoperatively. Results: Satisfactory C2PTS placement and atlantoaxial reduction were achieved in all patients. Postoperatively, no vertebral artery injury and implant failure were observed, and bone fusion was achieved in all the patients. Additionally, there were no VA occlusion or stenosis due to screws demonstrated on VA CT angiography. Conclusion: C2PTS can achieve three-column fixation of axis and is an efficient alternative to C2PS which is prohibited due to HRVA;also, gently mobilizing the HRVA inferiorly is mandatory to prevent vertebral artery injury during C2PTS placement.

关键词： Efficiency  

摘要： Adaptive educational games provide new opportunities to train early numerical skills. However, empirical evidence for the effectiveness of adaptive educational games is scarce. This study investigated the effectiveness of an adaptive game compared to a nonadaptive game in terms of cognitive, noncognitive and efficiency outcomes. In total, 84 children were randomly assigned to a condition in which children trained early numerical skills with an adaptive version of the Number Sense Game (NSG), or to a condition in which they trained with a nonadaptive version. Early numeracy was evaluated before the training, immediately after the training and 3 weeks after the training. Math anxiety (MA) was assessed before and 3 weeks after the training. The time children practiced with the NSG was used to assess efficiency. Results revealed that children in both conditions improved on early numerical ability, with sustained effects 3 weeks after the training. In both conditions, children's MA scores were lower after the training. Children in the adaptive condition learned more efficiently compared to the nonadaptive condition, and the interaction between prior knowledge and condition has shown that children with low prior knowledge benefited more from a nonadaptive training while children with high prior knowledge benefited more from an adaptive training in terms of learning efficiency. These results confirm that adaptive educational games can offer solace in terms of the need for differentiation.

关键词： Smart manufacturing systems   Robotics   Artificial intelligence   Digital transformation   Virtual commissioning  

摘要： Filling the gaps between virtual and physical systems will open new doors in Smart Manufacturing. This work proposes a data-driven approach to utilize digital transformation methods to automate smart manufacturing systems. This is fundamentally enabled by using a digital twin to represent manufacturing cells, simulate system behaviors, predict process faults, and adaptively control manipulated variables. First, the manufacturing cell is accommodated to environments such as computer-aided applications, industrial Product Lifecycle Management solutions, and control platforms for automation systems. Second, a network of interfaces between the environ-ments is designed and implemented to enable communication between the digital world and physical manufacturing plant, so that near-synchronous controls can be achieved. Third, capabilities of some members in the family of Deep Reinforcement Learning (DRL) are discussed with manufacturing features within the context of Smart Manufacturing. Trained results for Deep Q Learning algorithms are finally presented in this work as a case study to incorporate DRL-based artificial intelligence to the industrial control process. As a result, developed control methodology, named Digital Engine, is expected to acquire process knowledges, schedule manufacturing tasks, identify optimal actions, and demonstrate control robustness. The authors show that integrating a smart agent into the industrial platforms further expands the usage of the system-level digital twin, where intelligent control algorithms are trained and verified upfront before deployed to the physical world for implementation. Moreover, DRL approach to automated manufacturing control problems under facile optimization environments will be a novel combination between data science and manufacturing industries.

关键词： magnetic fields   MR‐   guided proton therapy   particle therapy   proton therapy   water phantom  

摘要： Purpose To design and commission a water phantom suitable for constrained environments and magnetic fields for magnetic resonance (MR)-guided proton therapy. Methods A phantom was designed, to enable precise, remote controlled detector positioning in water within the constrained environment of a magnet for MR-guided proton therapy. The phantom consists of a PMMA enclosure whose outer dimensions of 81x40x12.5cm3 were chosen to optimize space usage inside the 13.5-cm bore gap of the magnet. The moving mechanism is based on a low-height H-shaped non-ferromagnetic belt drive, driven by stepper motors located outside of the magnetic field. The control system and the associated electronics were designed in house, with similar features as available in commercial water phantoms. Reproducibility as well as accuracy of the phantom positioning were tested using a high-precision Leica AT 402 laser tracker. Laterally integrated depth dose curves and lateral beam profiles at three depths were acquired repeatedly for a 148.2 MeV proton beam in water. Results The phantom was successfully operated with and without applied magnetic fields. For complex movements, a positioning uncertainty within 0.16 mm was found with an absolute accuracy typically below 0.3 mm. Laterally integrated depth dose curves agreed within 0.1 mm with data taken using a commercial water phantom. The lateral beam offset determined from beam profile measurements agreed well with data from Monte Carlo simulations. Conclusion The phantom is optimally suited for detector positioning and dosimetric experiments within constrained environments in high magnetic fields.

关键词： blood irradiator dosimetry   chemical dosimeter   Fricke dosimetry   Gammacell 3000 Elan   Irradiation process   TA‐   GVHD  

摘要： Purpose The Fricke dosimeter has been shown to be a viable option as an absorbed dose standard. This work aims to provide the dose distribution in an irradiator container during blood irradiation using Fricke dosimetry. Methods Measurements were performed using a Gammacell Elan 3000 blood irradiator at Hemocenter in Rio de Janeiro, Brazil. A specific phantom was constructed and patented by the authors to perform these measurements. Fricke solution was prepared according to international protocols, and polyethylene bags filled with Fricke solution (n = 19) were spatially distributed within the phantom. Control bags were also submitted to the same process, except the irradiation. The irradiation time was calculated to give 25.7 Gy to the central portion of the phantom, the same dose used for blood bags. Results Encouraging results were obtained with an overall uncertainty of 2.1% (k = 1). The obtained results were compared with the doses calculated by the physicist from Hemocenter based on parameters provided by the manufacturer. The mean dose delivered to the Fricke bag in the center of the phantom (cavity 2) was 28.7 +/- 0.5 Gy, which is 12% higher than the planned dose of 25.7 Gy. Conclusions The obtained results showed that the setup (Fricke and phantom) is able to perform dosimetry for blood irradiators. The delivered dose was higher than expected. This highlights the importance in controlling all the parameters during irradiation to ensure the correct dose for all irradiated bags.

关键词： C2 translaminar screws   Craniocervical junction   Cervical instrumentation   Pediatric patients   Atlantoaxial  

摘要： Purpose The fusion of the upper cervical spine in children is demanding due to its reduced size, its anatomical complexity, or a severe pathology of the cranio-cervical junction. In some pediatric patients with today's more popular C1-C2 or, occipito-C2 techniques, it is impossible, or very risky to perform a short upper cervical fixation. Methods We present the utility and good results of ipsilateral laminar C2 screws insertion technique in two pediatric cases with low C2 laminar profile. Case 1: a 5-year-old child with a C1-C2 unstable subluxation, and a condylar assimilation of C1, where we performed an occipito-C2 fixation using an occipital plate and this modified translaminar C2 screw technique. Case 2: a 8-year-old Down syndrome boy who suffered an unstable subluxation of C1-C2 upon whom we performed a C1-C2 screw fixation using the same technique. Results Both cases have been followed up over a period of 7 and 2 years respectively, with good clinical results. Conclusions We describe the technique and the feasibility of the ipsilateral insertion of translaminar C2 screws in children with low laminar profiles, as a good alternative to other techniques when the anatomy of the C2 does not permit its use or make them very risky.

关键词： Scaling and root planing   Non-surgical periodontal therapy   Subgingival hard deposits   Training evaluation   Biofilm removal  

摘要： Objectives Whereas the key role of subgingival instrumentation in periodontal therapy is well known, the influence of operators' experience/training with different devices on treatment results is yet uncertain. Therefore, we assessed untrained undergraduate students, working on manikins, as to how effectively they learn to use curettes (GRA) and sonic scalers (AIR);hypothesizing that AIR will result in higher relative cleaning efficacy (RCE) than GRA. Material and methods Before baseline evaluation (T0), 30 operators (9 males, 21 females) received a 2-h theoretical lesson for both instruments, followed by a 12-week period with a weekly digitized training program for 45 min. During three sessions (T1-T3), the operators had to instrument six equivalent test teeth with GRA and AIR. At T0-T3, treatment time, proportion of removed simulated biofilm (RCE-b), and hard deposits (RCE-d) were measured. Results At T0, RCE-b was in mean(SD) 64.18(25.74) % for GRA, 62.25(26.69) % for AIR;(p = 0.172) and RCE-d 85.48(12.32) %/ 65.71(15.27) % (p < 0.001). At T3, operators reached highest RCE-b in both groups (GRA/AIR 71.54(23.90) %/71.75(23.05)%;p = 0.864);RCE-d GRA/AIR: 84.68(16.84) %/77.85(13.98) %;p < 0.001). Both groups achieved shorter treatment times after training. At T3, using curettes was faster (GRA/AIR 16.67(3.31) min/19.80(4.52) min;p < 0.001). Conclusions After systematic digitized training, untrained operators were able to clean 70% of the root surfaces with curettes and sonic scalers.