Modern Applications in Technology of Post and Core Restorations

Post and core devices are elements that contribute to the complete restoration of the coronary abutment, over which the final prosthetic restoration will be created. Their role is to retain the coronary portion of the restoration and to protect the remaining coronary structures. The retention function is dictated by the major indication of the method, massive coronary destruction that does not provide conditions for coronary aggregation of the restoration. Thus, this material is approaching two unique methods of making post and core devices totally metallic and/or hybrid (metal + totally ceramic component), using both classical technology, modern technologies, but also combinations of them.

Aerodynamic and Micro-Fluidic Effect in Masks with Impact in Covid-19 and Other Pandemic Propagation

US has ignored the hierarchy of pandemic control, misinformed population on virus propagation needed protection by using masks and other complementary protection measures facilitating the human disaster. The population mindset was to dismiss science, the virus and hope to dodge the pandemic with a fabric over the mouth and a free vaccine that will result in more than 600,000 deaths, and over 30 Million infected. In fact, masks are filters, and have a limited protection factor, known when used in medical practice. The masks were mainly designed and measured for stopping solid particulates, but when used against aerosolized watery droplets loaded with bio-agents nano-fluidic effects are responsible for anomalous, nonlinear and unpredictable complex behavior. Using an aerodynamic test bench, and various sizes of radioactive nano-powders, we performed measurements on the retention factor dependence for various filter materials of airflow magnitude, temperature, airflow regime, and filter's load. The results showed that a retention function of particle magnitude, measured for particulates, vary with temperature and when filter is used for aerosolized loaded watery droplets, an "atomization" effect happens transforming larger aerosols in finer ones, due to micro-nano-fluidic and aerodynamic instabilities. The measurements showed that pulsed and reciprocating airflow regimes trigger loaded filters to release some of previously retained particles, making the masks offer a reduced protection factor, and imposing special rules of safe usage. It was not told to public that is a contagious person uses correctly a mask, without any lateral leakage, through the mask passes nano-sized, airborne aerosols, containing virioli that float in air for weeks, driven by air currents, and special complementary measures to sterilize or remove the air have to be taken for safety.

CK2 phosphorylation of human papillomavirus 16 E2 on serine 23 promotes interaction with TopBP1 and is critical for E2 plasmid retention function

During the human papillomavirus 16 (HPV16) life cycle, the E2 protein interacts with host factors to regulate viral transcription, replication and genome segregation/retention. Our understanding of host partner proteins and their roles in E2 functions remains incomplete. Here, we demonstrate that CK2 phosphorylation of E2 on serine 23 promotes interaction with TopBP1 in vitro and in vivo, and that E2 is phosphorylated on this residue during the HPV16 life cycle. We investigated the consequences of mutating serine 23 on E2 functions. E2-S23A activates and represses transcription identically to E2-WT (wild-type), and E2-S23A is as efficient as E2-WT in transient replication assays. However, E2-S23A has compromised interaction with mitotic chromatin when compared with E2-WT. In E2-WT cells, both E2 and TopBP1 levels increase during mitosis when compared with vector control cells. In E2-S23A cells, neither E2 nor TopBP1 levels increase during mitosis. We next tested whether this difference in E2-S23A levels during mitosis disrupts E2 plasmid retention function. We developed a novel plasmid retention assay and demonstrate that E2-S23A is deficient in plasmid retention when compared with E2-WT. siRNA targeted knockdown of TopBP1 abrogates E2-WT plasmid retention function. Introduction of the S23A mutation into the HPV16 genome resulted in delayed immortalization of human foreskin keratinocytes (HFK) and higher episomal viral genome copy number in resulting established HFK. Overall, our results demonstrate that CK2 phosphorylation of E2 on serine 23 promotes interaction with TopBP1, which is critical for E2 plasmid retention function and in HPV16 immortalization of keratinocytes.ImportanceHuman papillomaviruses are causative agents in around 5% of all cancers, with no specific anti-viral therapeutics available for treating infections or resultant cancers. In this report, we demonstrate that phosphorylation of HPV16 E2 by CK2 promotes formation of a complex formation with the cellular protein TopBP1 in vitro and in vivo. This complex results in stabilization of E2 during mitosis and mediates plasmid retention by E2. This function promotes the partitioning of viral genomes into the nuclei of daughter cells following mitosis. We demonstrate that CK2 phosphorylates E2 on serine 23 in vivo, and that CK2 inhibitors disrupt the E2-TopBP1 complex. Mutation of E2 serine 23 to alanine disrupts the HPV16 life cycle, demonstrating a critical function for this residue. Together, our results suggest that CK2 inhibitors may disrupt the E2-TopBP1 dependent HPV16 life cycle and potentially kill HPV16 positive cancers, which lays a molecular foundation to develop novel therapeutic approaches for combating HPV16 disease.

Changes in Water Retention and Carbon Sequestration in the Huangshan UNESCO Global Geopark (China) from 2000 to 2015

Geopark ecosystem function assessments form an essential knowledge base for natural resource conservation and sustainable development. In this study, we evaluated changes in water retention and carbon sequestration in forests in the Huangshan United Nations Educational, Scientific, and Cultural Organization (UNESCO) Global Geopark (HUGG), China, from 2000 to 2015. We analyzed the relationship between these ecosystem functions and various controlling factors. The ecosystem functions in HUGG experienced significant changes during the study period. Water retention function increased slightly (0.15 m3 hm−2 year−1), while carbon sequestration increased sharply (25.57 g C m−2 year−1), with both showing increased spatial homogenization. Increased precipitation significantly enhanced the water retention function, whereas a temperature increase had a positive effect on the carbon sequestration. Both water retention and carbon sequestration decreased significantly with increased tourist disturbance. Pearson’s correlation coefficient and variance partitioning analysis identified the climate factors and tourist disturbance controlling water retention and carbon sequestration, respectively. The fitted structural equation model showed that climate factors had a greater total impact on water retention than tourist disturbance, while the total impact of climate factors on carbon sequestration was far less than that due to tourist disturbance. This study untangled the relationship between ecosystem functions (water retention and carbon sequestration) and influential factors in the HUGG and clarified that climate factors and tourist disturbance were determinants of changes in these ecosystem functions. The results from this study provide scientific foundations for the sustainable management of natural ecosystems in the HUGG and other geoparks.

Uncertainty quantification of bioassay functions for the internal dosimetry of radioiodine

Bioassay functions, which are provided by the International Commission on Radiological Protection, are used to estimate the intake activity of radionuclides; however, they include considerable uncertainties in terms of the internal dosimetry for a particular individual. During a practical internal dose assessment, the uncertainty in the bioassay function is generally not introduced because of the difficulty in quantification. Therefore, to clarify the existence of uncertainty in the bioassay function and provide dosimetrists with an insight into this uncertainty, this study attempted to quantify the uncertainty in the thyroid retention function used for radioiodine exposure. The uncertainty was quantified using a probabilistic estimation of the thyroid retention function through the propagation of the distribution of biokinetic parameters by the Monte Carlo simulation technique. The uncertainties in the thyroid retention function, expressed in terms of the scattering factor, were in the ranges of 1.55–1.60 and 1.40–1.50 for within 24 h and after 24 h, respectively. In addition, the thyroid retention function within 24 h was compared with actual measurement data to confirm the uncertainty due to the use of first-order kinetics in the biokinetic model calculation. Significantly higher thyroid uptakes (by a factor of 1.9) were observed in the actual measurements. This study indicates that consideration of the uncertainty in the thyroid retention function can avoid a significant over- and under-estimation of the internal dose, particularly when a high dose is predicted.

How much do Japanese university students know about soil? A survey of university students who received science education in Japanese schools

<p>In the science curriculum in Japan, as Mori et al. (2019) examined the content of course of study for elementary schools, there are opportunities to plant and grow plants in soil, and to learn about the erosion, movement, and deposition of sediment. However, the science curriculum does not include specific learning content about the characteristics and functions of soil. Furthermore, in the new course of study to be implemented in 2020 (Ministry of Education, Culture, Sports, Science and Technology, 2017), an emphasis is placed on science education aimed at the prevention of natural disasters (sediment-related disasters caused by localized rainfall, etc.), which have caused substantial damage in Japan recently. Thus, in the current reality of science education in Japan, there are no occasions for teaching about how ordinary soil supports our lives and affluent living.<br>The purpose of this study is to obtain suggestions on what should be taught at schools about soil by conducting a survey of university students who received such school education in Japan, to investigate their level of comprehension regarding the characteristics and functions of soil. <br>The survey was conducted in October 2019 in Tochigi Prefecture. Participants comprised 253 first-year university students who had just graduated from a high school (78 students majoring in humanities and social sciences, 175 students majoring in agricultural studies). The survey was in the form of a questionnaire. Soil’s “water retention” function received particular attention in this study. To survey the students’ understanding, they were asked the following two open-ended questions. Question 1: Why do plants require watering to grow? Question 2: How can weeds that grow on the roadside do so without watering? The first question was intended to examine the students’ understanding of why plants require watering to grow, while the second question was intended to assess their understanding of the water retention function of soil.<br>The most common answer to the first question was “Water is necessary for the growth of plants.” Sixty-five students majoring in humanities and social sciences and 165 students majoring in agricultural studies provided this answer. Approximately 25% of these students mentioned the mechanism of photosynthesis. Nearly half of the students answered, “because weeds are strong,” to the second question, which was the common answer. Twenty-six students majoring in humanities and social sciences and 77 students majoring in agricultural studies answered, “because it rains,” which was the second most common answer to the second question. Only four students majoring in agricultural studies, all of whom had attended university lectures on dendrology, were able to answer with reference to the water retention function of soil. <br>The responses provided in this survey indicate that while the students were taught that plants require water for growth, they were not educated about soil and its functions that are necessary for this process, which arguably shows the results of the science curriculum in Japan. Thus, it is necessary to develop teaching materials and lessons that will educate students about the characteristics and functions of ordinary soil. </p>