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Purpose: Although physical activity (PA) has been consistently associated with breast cancer, existing evidence is limited to self-reported physical activity, which is prone to dilution bias. Therefore, this aims to examine the associations of device-measured PA domains with breast cancer risk and whether it differs by menopausal status. Methods: Prospective cohort study. Data from 48,286 women from the UK Biobank cohort were analyzed. A wrist triaxial accelerometer was used to collect physical activity data for light, moderate, vigorous, moderate to vigorous, and total PA. Cox proportional models were performed to examine the association between PA domains, menopausal status, and breast cancer risk. Results: Eight hundred thirty-six breast cancer cases were diagnosed during a median of 5.4 years (interquartile range: 4.7–5.9). For total PA, those in the most active quartile had a 26% lower risk of breast cancer (Hazard ratio [HR]: 0.74; 95% confidence interval [CI], 0.61–0.91) compared with those least active. Similar results were observed for light PA (HR: 0.79; 95% CI, 0.64–0.96), and moderate to vigorous PA (HR: 0.78; 95% CI, 0.64–0.96). However, moderate PA (HR: 0.73; 95% CI, 0.44–1.19) and vigorous PA (HR: 0.77; 95% CI, 0.56–1.05) was nonsignificant. No evidence of interaction between PA domains and menopause status was found (P >.10). Conclusion: High levels of PA are associated with a lower risk of breast cancer with similar magnitude of associations observed across different intensity domains. [ABSTRACT FROM AUTHOR]

Collaborative group work has been recognized as a way of fostering the development of metacognition and self-regulation. Moreover, it has been claimed that these regulatory processes have an interpersonal level in which the regulation of the activity is shared with others (Iiskala et al., 2004). There has also been a considerable body of research on talk within small groups in the classroom. This approach has built a considerable amount of research, given the demonstrated effect of certain types of talk on academic learning. However, very few studies look at both aspects of collaboration (Mercer, 2013). The present research aims to investigate the relationship between socially shared regulation of learning (SSRL) and type of talk. Two hundred and thirty-one groups of three students were videotaped solving a problem in collaboration. Videos were analyzed qualifying exploratory talk and two dimensions of SSRL: metacognitive regulation and symmetry and reciprocity. Results show that the dimensions of SSRL and quality of talk correlate significantly when the whole sample is considered. However, when the sample is segmented by age, differential patterns start to emerge. Theoretical, methodological, and practical implications are discussed.

Inverse associations between dietary fiber (DF) and colorectal cancer risk are well-established. However, evidence is limited in relation to other cancer sites. This study, of 364,856 participants from the UK Biobank, aimed to evaluate the associations between total and source-specific partial DF and risk of 17 specific cancers and all cancers combined. Partial DF was derived from baseline touchscreen questionnaire data on cereal, bread, fruit, and vegetable intake. The outcomes were incident cancer at 17 sites and all cancers combined. Cox proportional hazards models were applied. Over a median 8.8-year follow-up period, 30,725 people were diagnosed with cancer. After adjusting for sociodemographic and lifestyle factors, those in the highest quintile of partial DF compared with the lowest quintile (<9.6 vs ≥19.1 g/day) had 10% lower risk of cancer overall, with the greatest risk reductions observed for cervical (hazard ratio (HR) = 0.33, 95% confidence interval (CI): 0.14; 0.82), esophageal (HR = 0.66, 95% CI: 0.52; 0.84), lung (HR = 0.67, 95% CI: 0.59; 0.76), bladder (HR = 0.72, 95% CI: 0.56; 0.91), and kidney (HR = 0.75, 95% CI: 0.61; 0.92) cancers. Associations between DF and lung cancer were observed only in current and former smokers. Higher DF intake, in particular cereal fiber and fruit and vegetable fiber, was associated with a lower risk of overall and multiple site-specific cancers. [ABSTRACT FROM AUTHOR]

Germplasm collection and characterization is essential for plant breeding. Chile holds a collection of 347 Vitis accessions at Instituto de Investigaciones Agropecuarias, La Platina, that have been successfully used to develop new table grape cultivars such as Maylen®. Located in the central valley of Chile, a section of the Vitis collection was characterized for two consecutive seasons for phenology as well as fruit quality parameters at harvest. In terms of phenology, the collections can be grouped in four main clusters, with a higher representation of individuals at the middle and late timing. Fruit phenotyping showed significant differences among wine and table grapes for cluster and berry weight, seed number and fresh seed weight, polar and equatorial diameters, as well as the ratio among these parameters. Interestingly, rachis weight, a novel parameter associated with fruit storage capacity, did not show differences among groups. Other novel traits, such as the combination of commercial seedleesness and berry equatorial diameters above 2cm were less represented, suggesting the need to create and introduce genetic variability for table grape breeding purposes.

This paper addresses the perceived consequences of the Chilean national teacher evaluation system. We interviewed 57 school leaders in 30 schools across 10 municipalities about effects and uses of the assessment in their schools. Results show that in the large majority of schools our interviewees observe positive effects such as increased teamwork and internal reflection processes based on the assessment results. Reports about effects at teacher level far outnumber institutional effects, and are mixed. In all schools our interviewees report on teachers' negative emotions and work overload due to the assessment process, but also about their internalization of the underlying professional standards. The paper analyzes differences among schools and offers suggestions for the development of large-scale standardized teacher evaluation systems. (Contains 2 tables.)

The paper describes a study conducted to explicate the multiple theories underlying Chile's national teacher evaluation program. These theories will serve as the basis for evaluating the intended consequences of this evaluation system, while not losing sight of emerging unintended consequences. We first analyzed legal and policy documents and then interviewed fourteen representatives of the four stakeholder groups involved in the program's design and implementation, in order to gain insight into their respective conceptions of the program's functioning and intended effects. The results show that, as to be expected and despite the long and difficult negotiation process that preceded implementation of this program, multiple political stakeholders still view the program's intended effects differently. However, there was substantial overlap regarding a number of intended effects, such as building the capacity of, and triggering change in, teachers with shortcomings, and informing the selection of new teachers and facilitating the exit of unsatisfactory teachers from the system. It was difficult to get interviewees to talk about how exactly these intended effects are supposed to be achieved. The paper draws conclusions regarding theory elaboration process involving multiple stakeholders in a highly political context. (Contains 2 tables and 5 figures.)

Ballast is essential for vessels to lower their centre of gravity, improve stability, and ease their motion during sailing. During the modern period, heavy materials used for ballasting ships were an issue of particular concern for both authorities and ship owners, subjected to increasing control, regulation, and standardisation. These items represent a very common find in wreck sites and deserve special attention, as their characteristics, distribution, and provenance can deliver critical information for assessing where the vessel was ballasted, sailing routes, ship tonnage, and site formation processes. This article is centred on pig iron ingots, introduced in the early 18th century in sailing warships and shortly thereafter in sizeable merchant vessels, a type of ballast which is frequently overlooked in archaeological research. In particular, specimens retrieved from the Chilean Navy armed transport Infatigable (1855) were analysed through macroscopic and physicochemical characterisation using LM, SEM-EDS, WD-XRF, and IGF. The results obtained indicate the ingots were manufactured with cast iron of different quality, suggesting they may have come from different production centres. The investigation resulted in a better understanding of ballasting practices on a South American navy ship in the early post-independence period and provided new data for discussions of off-site and non-nautical technological issues, such as the materials, knowledge, and techniques associated with the production of pig iron in the mid-19th century. [ABSTRACT FROM AUTHOR]

The genus Telmatobius Wiegmann, 1834 is composed of a wide variety of species and is one of the most diverse native components of the high-altitude Andean environments. The species of the genus present in Chile are considered as endangered, critically endangered or data deficient. We isolated and evaluated 44 microsatellites in 80 individuals of 8 species of Telmatobius present in Chile, obtaining 22 polymorphic microsatellite loci for Telmatobius chusmisensis. The cross-amplification test was successful in all other species tested. For the first time, microsatellite markers are described for Telmatobius. The description of these primers will be useful for further genetic studies for T. chusmisensis and other species of the same genus; allowing further analyses of population structuring, dispersal patterns, recent demographic history and population effective size. This information is also significant to undertake conservation actions for the species of the genus Telmatobius, since most species have conservation issues. [ABSTRACT FROM AUTHOR]

Big-vein disease (BVD) is a widespread and economically damaging disease in lettuce (Lactuca sativa L.). Typical symptoms are chlorotic clearing around leaf veins, leaf deformations, and impaired head development. In this research, we studied the relationship between symptom intensity and protein and viral RNA accumulation in infected plants. Naturally infected lettuce plants, from the field or greenhouse, were classified according to their symptomatology: mild, moderate, severe, and symptomless. Coat protein accumulation was evaluated by a double antibody sandwich/enzyme-linked immunosorbent assay (DAS-ELISA), and RNA levels were studied by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and quantitative RT-PCR. Virus coat protein accumulation did not differ for the two viruses associated with this disease among lettuce plants showing different symptom severity. Similarly, abundance of Mirafiori lettuce big-vein virus (MLBVV)-RNA3 or Lettuce big-vein associated virus (LBVaV)-RNA-2 were not different (P > 0.05) for diverse big vein disease severity rating scales. This suggests that symptom severity expressed by big-vein diseased lettuce plants did not necessarily reflect the accumulation of viruses associated with this disease in the host. Therefore, lettuce plants showing mild symptoms of BVD do not necessarily present lower virus levels than plants showing more severe symptomatology. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Methods Results Conclusions The visceral adiposity index (VAI) is a marker of visceral fat accumulation and metabolic dysfunction, but there is limited evidence of its association with cancer. The objective of this study was to investigate associations between the VAI and both incident cancer at 23 sites and all‐cause cancer.In total, 385,477 participants (53.3% women; mean age, 56.3 years) from the UK Biobank prospective cohort were included in this study. The median follow‐up was 8.2 years (interquartile range, 7.3–8.9 years). The VAI was calculated using formula the published by Amato et al. and was categorized into sex‐specific tertiles. Twenty‐four incident cancers were the outcomes. Cox proportional hazard models were adjusted for sociodemographics, lifestyle factors, and multimorbidity counts.Over the follow‐up period, 47,882 individuals developed cancer. In the fully adjusted models, the VAI was associated with a higher risk of six cancer sites. Individuals in the highest tertile, compared with those in the lowest tertile, had higher risks of uterine (hazard ratio [HR], 2.09; 95% confidence interval [CI], 1.76–2.49), gallbladder (HR, 1.83; 95% CI, 1.26–2.66), kidney (HR, 1.39; 95% CI, 1.18–1.64), liver (HR, 1.25; 95% CI, 1.00–1.56), colorectal (HR, 1.14; 95% CI, 1.05–1.24), and breast (HR, 1.11; 95% CI, 1.03–1.19) cancers and of all‐cause cancer (HR, 1.05). There was no evidence of a nonlinear association between the VAI and cancer risk.The VAI was associated with six cancer sites and with all‐cause cancer. The prognostic and etiologic roles of visceral fat accumulation and dysfunction in cancer warrant further research. [ABSTRACT FROM AUTHOR]

The purpose of this work was to evaluate the role of non-caloric sweeteners in pastry products considering the product made with sugar as a control sample. Sensory preference and acceptability with consumers were determined through ranking test and 9-point hedonic scale respectively. The satiation and satiety were determined by the visual analogue scale (VAS). In addition, caloric intake; macronutrients; physical parameters such as yield, specific volume, hardness, cohesiveness, and gum; stability in storage time by microbiological analysis; and moisture variation of the samples were calculated. The results showed that the preference and sensory acceptability is significantly (p < 0.05) higher in the control sample; the sweeteners decreased the sensory response, but not the satiation and satiety, although these are not related to the sensory response and did not present significant differences with the control sample, except in the satiation parameter of the sample sweetened with Stevia. The physical and texture parameters highlight the best quality of the control sample and are related to the sensory response. The shelf life is also greater in the control sample, which shows that sugar contributes sweetness and other technological characteristics related to texture, stability during storage, aroma, color, and flavor, thanks to the Maillard reaction. [ABSTRACT FROM AUTHOR]

Choclero is a Chilean pre-Columbian floury corn with great economic value. The genebanks network of the Instituto de Investigaciones Agropecuarias (INIA) have preserved the largest Choclero corn collection, which is underutilized despite the existence of several Choclero breeding programs. This germplasm could serve as a valuable resource in breeding for green corn yield and cooking/eating quality. To use such materials, however, breeders need information about extent and distribution of genetic diversity present within the collection. Ten simple sequence repeats (SSRs) markers were used for population genetic analysis of 34 Choclero corn landraces collected from different places of Chile and 22 inbred lines developed by the INIA corn breeding program, of two sources: Choclero landraces and commercial hybrid S 1 segregant populations. Number of alleles, gene diversity per locus, unique alleles per locus and population structure all differ between the two germplasm groups. In the landraces group, two genetic subgroups were identified. Several landraces accessions were considered as mixed. Linking genetic diversity information with vernacular name and historical events allowed us to understand the origin of this admixed group. Our results suggest that this group are open pollinated Choclero varieties released by INIA in the 1970s. A reclassification based on the original biological status is proposed. The results highlight the importance of intra-racial studies for understanding diversification and origin of local corn accessions. Data also suggests that there is scope for exploiting the genetic diversity of Choclero germplasm for Choclero corn improvement. [ABSTRACT FROM AUTHOR]

The aim of this research was the development and characterization of three gel dosage forms of Halobetasol propionate loaded lipid nanoparticles (HB-NLC) for the treatment of inflammatory skin diseases. A Pluronic gel (Pl-HB-NLC), a Carbopol gel (Cb-HB-NLC) and a Cremigel (Cg-HB-NLC), were characterized for stability, swelling, degradation, porosity and rheology. The biopharmaceutical behavior of in vitro release and ex vivo permeation, along with microbiological stability were also evaluated. Tolerance and therapeutic efficacy were determined in vivo. The gels proved to have eudermic pH and to be effective to improve HB-NLC stability for more than 6 months. In vitro drug release profiles were adjusted to a first order (Pl-HB-NLC, Cg-HB-NLC) and hyperbola (Cb-HB-NLC) kinetic models, revealing sustained drug release. Ex vivo biopharmaceutical behavior showed slow drug penetration through skin, delaying the drug entrance into systemic circulation. The formulations were effective in reducing inflammation with a lower drug dose in comparison with existing treatments, obtaining the fastest effect when using Pl-HB-NLC. After application of the formulations in volunteers, no irritation, redness or edema reactions were detected, plus, an enhancement of the biomechanical properties of the skin was evidenciated. Therefore, the results indicate that these formulations are a suitable alternative to current treatments. [ABSTRACT FROM AUTHOR]