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Teacher attrition has been a global concern for many decades, with teachers leaving the profession at a higher rate than those entering. The largest group effected by this attrition issue is the beginning teacher. (Hong, 2010). In fact, in the United States, 30-50% of new teachers leave the field within the first five years. Many studies have been conducted to find out why this is occurring year after year--and the themes of "demographic characteristics and school contexts" (Hong, 2010,p.1531) often surface. Interestingly, although these themes are popular reasons, neither of them truly clarify how teachers identified with their classroom or daily school experiences, how they internalized the external conditions, or how they perceived themselves as educators. These thoughts need to be investigated to determine if they actually impact the final decision to leave the teaching profession (Hong, 2010). Hong (2010) researched the retention issue further and reported that in fact "such a career decision tends to be closely associated with the teacher's own sense of self and identity as a teacher" (p. 1531). The strength of this identity appeared to be the foundation needed to handle the other issues addressed as reasons for the low beginning-teacher retention rate. He felt it was therefore "essential to focus on the continuously developing teacher identity, which may lie behind the dropout phenomenon" (p. 1531). If this is true then the four real questions teacher preparation faculty need to ask are: (1) Are students creating their teacher identity when they establish education as their major of study; (2) Are students delaying the creation of their teacher identity till they enter the field as new teachers; (3) How can faculty pinpoint the time frame of engagement in this teacher identity process; and (4) How can faculty help build the strength of teacher identity for future resiliency in the field?

The COVID-19 pandemic has created a worldwide healthcare crisis. Convolutional Neural Networks (CNNs) have recently been used with encouraging results to help detect COVID-19 from chest X-ray images. However, to generalize well to unseen data, CNNs require large labeled datasets. Due to the lack of publicly available COVID-19 datasets, most CNNs apply various data augmentation techniques during training. However, there has not been a thorough statistical analysis of how data augmentation operations affect classification performance for COVID-19 detection. In this study, a fractional factorial experimental design is used to examine the impact of basic augmentation methods on COVID-19 detection. The latter enables identifying which particular data augmentation techniques and interactions have a statistically significant impact on the classification performance, whether positively or negatively. Using the CoroNet architecture and two publicly available COVID-19 datasets, the most common basic augmentation methods in the literature are evaluated. The results of the experiments demonstrate that the methods of zoom, range, and height shift positively impact the model's accuracy in dataset 1. The performance of dataset 2 is unaffected by any of the data augmentation operations. Additionally, a new state-of-the-art performance is achieved on both datasets by training CoroNet with the ideal data augmentation values found using the experimental design. Specifically, in dataset 1, 97% accuracy, 93% precision, and 97.7% recall were attained, while in dataset 2, 97% accuracy, 97% precision, and 97.6% recall were achieved. These results indicate that analyzing the effects of data augmentations on a particular task and dataset is essential for the best performance. Doi: 10.28991/ESJ-2023-SPER-01 Full Text: PDF

Abstract Introduction Aging is an independent risk factor for cardiovascular events. It promotes vascular dysfunction which is associated with risk factors for cardiovascular diseases (CVDs). Exercise can modulate vascular function parameters, but little is known about the effects of different modalities of training (aerobic, resistance, and combined) on endothelial function and arterial stiffness in older adults. Methods This systematic review study will include randomized controlled trials (RCTs) selected from the electronic databases MEDLINE (PubMed), Cochrane, LILACS, EMBASE, and Web of Science. We will follow the PRISMA guidelines and PICOS framework. Studies involving both male and female older adults (≥60 years old) with or without comorbidities undergoing aerobic, resistance, and/or combined training compared to a control group (no exercise) will be eligible. We will use the Cochrane Risk of Bias 2 (RoB 2) tool to evaluate the quality of individual studies and GRADE to assess the strength of evidence. Statistical analyses will be conducted with RStudio for Windows (v1.3.959) using R package meta. Discussion A systematic review and meta-analysis involving data from studies of older adults would deepen our understanding of vascular adaptations to exercise training in this population. It could provide new insights into how health providers can improve patient management and prevention of cardiovascular events in older adults. Systematic review registration PROSPERO 42021275451

Rootstock election is one of the key decisions when designing a vineyard. Although the research performed to determine the effect they induce in the behaviour of scion varieties is not scarce, it is not easy to have a global idea, as results are usually published scattered. In this work, we re-examine previous research conducted in Spain on rootstock implications on vine agronomic performance through the performance of a meta-analysis (MA). As a result, we were able to integrate the information reported in 20 articles that included rootstock experimentation conducted with 36 different varieties and 47 different rootstocks, totalling 764 individual records. However, when the information was filtered before the meta-analysis, this number decreased to 312 records, for which rootstock Response Ratios (RR) were calculated. The characteristics conferred by the rootstock were more closely related to the rootstock itself, rather than to the characteristics of the Vitis sp. crossing used to create the rootstock. Several rootstocks were identified as more suitable for adapting to future climate change conditions, as far as they were able to moderate sugar accumulation and pH (161-49 C, 41-B MGt and 420A MGt). Meanwhile, 140 Ru and 5-BB were observed to provide high pH and sugar contents despite their high yield. In conclusion, despite being based on data from a single country, the meta-analysis was shown to be a useful tool for enhancing the value of previous research on rootstocks. Combining articles from both peer-reviewed and technical journals helped in the assessment of the implications of different rootstocks, although further steps should be taken to facilitate data integration (harmonisation of measurement and reporting procedures, open data repositories, etc).

Picornavirus genome replication takes place in specialized intracellular membrane compartments that concentrate viral RNA and proteins as well as a number of host factors that also participate in the process. The core enzyme in the replication machinery is the viral RNA-dependent RNA polymerase (RdRP) 3Dpol. Replication requires the primer protein 3B (or VPg) attached to two uridine molecules. 3B uridylylation is also catalysed by 3Dpol. Another critical interaction in picornavirus replication is that between 3Dpol and the precursor 3AB, a membrane-binding protein responsible for the localization of 3Dpol to the membranous compartments at which replication occurs. Unlike other picornaviruses, the animal pathogen foot-and-mouth disease virus (FMDV), encodes three non-identical copies of the 3B (3B1, 3B2, and 3B3) that could be specialized in different functions within the replication complex. Here, we have used a combination of biophysics, molecular and structural biology approaches to characterize the functional binding of FMDV 3B1 to the base of the palm of 3Dpol. The 1.7 Å resolution crystal structure of the FMDV 3Dpol -3B1 complex shows that 3B1 simultaneously links two 3Dpol molecules by binding at the bottom of their palm subdomains in an almost symmetric way. The two 3B1 contact surfaces involve a combination of hydrophobic and basic residues at the N- (G5-P6, R9; Region I) and C-terminus (R16, L19-P20; Region II) of this small protein. Enzyme-Linked Immunosorbent Assays (ELISA) show that the two 3B1 binding sites play a role in 3Dpol binding, with region II presenting the highest affinity. ELISA assays show that 3Dpol has higher binding affinity for 3B1 than for 3B2 or 3B3. Membrane-based pull-down assays show that 3B1 region II, and to a lesser extent also region I play essential roles in mediating the interaction of 3AB with the polymerase and its recruitment to intracellular membranes.

Under semiarid and warm climates, field practices for climate change adaptation have to be defined in order to modulate grape composition according to the desired wine styles. Under this context, the present study investigated several viticulture practices in cv. Macabeo for Cava production. The experiment was carried out over 3 years in a commercial vineyard located in the province of Valencia (eastern Spain). The techniques tested were (i) vine shading, (ii) double pruning (bud forcing), and (iii) the combined application of soil organic mulching and shading, all of them tested against a control. Double pruning significantly modified phenology and grape composition, improving the wine alcohol-to-acidity ratio and reducing the pH. Similar results were also achieved by shading. However, the shading strategy did not significantly affect yield, unlike double pruning, which reduced vine yield even in the year following its application. Shading alone or in combination with mulching significantly improved the vine water status, suggesting that these techniques can also be used to alleviate water stress. Particularly, we found that the effect of soil organic mulching and canopy shading on stem water potential was additive. Indeed, all the techniques tested were useful for improving wine composition for cava production, but double pruning is only recommended for premium Cava production.

Optical-responsive nanodroplets have recently been studied as a new mode of remotely controlled drug delivery. As a class of new emerging smart drug carriers, NIR-absorber-loaded perfluorocarbon nanodroplets can be converted into gas bubbles through laser stimulation, called optical droplet vaporization (ODV), which provides a potential strategy to deliver therapeutic agents to solid tumors on demand. However, there is a lack of suitable technologies to monitor these drug-loaded nanodroplet behaviors in vivo, and control the site and amount of drug released. In this study, ultrasound and photoacoustic imaging technology were applied to directly monitor optical-responsive, drug-loaded nanodroplets within the tissue. We explored the effects of laser energy, repetition rate, and number of pulses on the release profiles of the delivered drug as well as ultrasound and photoacoustic imaging signal-intensity curves. The conducted studies demonstrated that this noninvasive technology helped determine the optimum time point for laser activation on accumulated drug-loaded nanodroplets within tissues, allowing for the potential to effectively treat pathologies while minimizing drug-related toxicities.

Firma Invitada del número 50 de la revista Relaciones Internacionales.

El presente artículo intenta actualizar una definición finalista de la universidad en virtud de su misión social. En su diagnóstico inicial, esta investigación se interrogará por las cualidades, funciones y objetivos que son específicos de la universidad y que, por este motivo, no pueden ser sustituidos por otras instituciones o prácticas alternativas en nuestra sociedad. Proponemos, por ello, brindar una definición funcional y de propósito para las instituciones universitarias, preferentemente aquellas que no tienen ánimo de lucro. Nuestra investigación atenderá, fundamentalmente, a los datos relativos al Sistema Universitario Español y se servirá de marcos preferentemente clásicos del pensamiento contemporáneo en el establecimiento del propósito institucional de las universidades. Metodológicamente referiremos algunos datos cuantitativos y sus fuentes, aunque este trabajo aspira a proponerse como una reflexión crítica aunque con eminente vocación práctica. Se trata, por lo tanto, de una reflexión operada desde la filosofía (o, más genéricamente, desde las humanidades) y no desde las ciencias sociales en un sentido estricto. Los presupuestos teóricos de los que partiremos adquieren una deuda singular con Max Weber, Jacques Derrida y más específicamente Ortega y Gasset, aunque dialogarán también con referencias más contemporáneas como Anne Applebaum o Jonathan D. Haidt. Asimismo, a lo largo de este texto se incorporarán referencias de la filosofía clásica y medieval que consideramos pueden seguir reivindicando una vigencia objetiva. A partir de estas premisas teóricas intentaremos actualizar la misión de la universidad contemporánea, subrayando sus implicaciones sociales y culturales y su responsabilidad política específica en la promoción y custodia de ciertas jerarquías epistémicas en el marco de una sociedad plural y democrática.

Photothermal therapy (PTT) is a type of cancer treatment capable of damaging tumors using laser irradiation. This procedure can be a promising approach to complement current cancer therapies, due in part to its minimal invasiveness. One of the challenges of photothermal therapy is the potential collateral damage to the surrounding healthy tissue, as well as excessive temperature increase in the target tumor region that can cause tissue carbonization and evaporation. With the aim of increasing the performance of photothermal therapy in damaging targeted tumor while keeping healthy nearby tissue unaffected, this research proposes the use of a feedback control system that considers the cumulative thermal damage to both types of tissue. Two separate control algorithms (fuzzy logic and PI) were designed and tested in silico using simulations made in MATLAB® and Python. Results showed that both controllers successfully accomplished the proposed goals. Therefore, the feasibility of using these automated systems to improve the efficacy and safety of PTT was demonstrated. [ABSTRACT FROM AUTHOR]