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To investigate an outbreak of acute gastroenteritis caused by norovirus (NoV) in a long-term care facility (LTCF) in Portugal to describe and estimate its extent, and we implemented control measures.
Probable cases were residents or staff members in the LTCF with at least 1 of the following symptoms: (1) diarrhea, (2) vomiting, (3) nausea, and/or (4) abdominal pain between October 31 and December 8, 2017. Confirmed cases were probable cases with positive NoV infection detected by real-time polymerase chain reaction (RT-PCR) and the same genotype in stool specimens.
The outbreak was caused by NoV GII.P16-GII.4 Sydney 2012 variant and affected 146 people. The highest illness rates were observed in residents (97 of 335, 29%) and nurses (16 of 83, 19%). All 11 resident wards were affected. Data on cases and their working or living areas suggest that movement between wards facilitated the transmission of NoV, likely from person to person.
The delay in the identification of the causative agent, a lack of restrictions of resident and staff movement between wards, and ineffective initial deep-cleaning procedures resulted an outbreak that continued for >1 month. The outbreak ended only after implementation of strict control measures. Recommendations for controlling future NoV outbreaks in LTCFs include emphasizing the need to control resident’s movements and to restrict visitors, timely and effective environmental cleaning and disinfection, leave of absence for ill staff, and encouraging effective hand hygiene.
The aim of this study is to investigate the impact of anatomical changes in prostate cancer patients on the target coverage when using 6 MV beams-VMAT therapy and to propose strategies that allow us to evaluate the dose or correct it by normalization without having to perform a new simulation.
Methods and materials:
Ten patients of high-risk prostate cancer were chosen for the study. All test plans were delivered using the same isocenter and monitor units as the original plan and compared against the original unedited plan. The expansion and contraction of body contours due to size changes was mimicked by increasing and decreasing the body contour with depths of −2, −1·5, …, 1·5, 2 cm, in the anterior, and both lateral directions of the patient. A total of 90 plans were evaluated, 9 for each patient. Dose-volume histogram statistics were extracted from each plan and normalized to prescription dose.
Weight changes resulted in considerable dose modifications to the target and critical structures. Plans were found to be varied with 2·9% ± 0·3% per cm SSD change for VMAT treatment with a correlation index close to one. Therefore, doses variations were linear to the changes of depth. Gamma index evaluation was performed for the 10 renormalized plans. All of them passed criteria of 3%/3 mm in at least 98.2% of points. Eight of them passed criteria in 99% points. Gamma index 4%/4 mm passed 100% points in all patients for the chosen region of interest.
The dosimetry estimation presented in this study shows important data for the radiation oncology staff to justify whether a CT rescan is necessary or not when a patient experiences weight changes during treatment. Based on the results of our study, discrepancies between real dose and planned dose were >5% for 1·7 cm of difference in external contour in the anterior and both lateral directions of the patient.
Bilingualism has been said to improve cognition and even delay the onset of Alzheimer's disease (AD). This research aimed to investigate whether bilingualism leaves a neurophysiological trace even when people are highly educated. We expected bilinguals to present better preserved brain functional networks, which could be a trace of higher cognitive reserve. With this purpose, we conducted a magnetoencephalographic study with a group of healthy older adults. We estimated functional connectivity using phase-locking value and found five clusters in parieto-occipital regions in which bilinguals exhibited greater functional connectivity than monolinguals. These clusters included brain regions typically implicated in language processing. Furthermore, these functional changes correlated with caudate volumes (a key region in language shifting and control) in the bilingual sample. Interestingly, decreased Functional Connectivity between posterior brain regions had already been identified as an indicator of aging/preclinical AD but, according to our study, bilingualism seems to exert the opposite effect.
Organizations have to strive in an uncertain and challenging environment. Hence, the role resilience played at work has been of special interest in the last decade, although empirical research is still scant, especially regarding the antecedents and the consequences resilience has. In this study we analyse the role corporate social responsibility plays towards employees (CSRE) in the promotion of resilience at work, and how resilience results in organizational learning capability (OLC) and firm performance. Structural equation modelling was used to test our model with a sample of 296 companies from different sectors. Results show that CSRE had a positive influence on organizational resilience, which in turn affected firm performance via OLC. Therefore, we tested the antecedents and consequences resilience had empirically, whose practical implications in terms of further human resource management activities are also discussed.
The origins of ancient states is an important archaeological research topic that illuminates the precursors of modern nations. Public buildings, as is the case today, created urban settings in which political, administrative and religious functions were undertaken. This investigation of the ancient Mesoamerican kingdom of Izapa reveals a network of urban centres laid out according to shared design principles. While the capital city of Izapa has long been known, the authors’ research reveals, for the first time, the entire Izapa kingdom. This work provides an important new insight into the origins of political hierarchy and urban life in pre-Hispanic Mesoamerica.
The parental bonding is influenced by two dimensions: care and control or protection over the child of both parents. The lack of care during childhood may make the individual more susceptible to the onset of psychiatric disorders when adult. These psychiatric disorders when present during pregnancy may have a negative impact on the health of pregnant women and children. The aim of this study was to assess the association between generalized anxiety disorder (GAD) in pregnant adolescents and the perception of parental bonding.
This is a cross-sectional study with 871 pregnant women under the age of 19, receiving prenatal care in 47 Basic Health Units in the one city, Brazil. The generalized anxiety disorder was measured using the Mini International Neuropsychiatric Interview (MINI) and the perception of parental bonding in childhood using the Parental Bonding Instrument (PBI).
The prevalence of GAD was 8.5%. Among all the parental bonding dimensions, only a perceived lack of maternal care under 16 years was associated with GAD.
The results showed that only the perception of maternal bonding was associated with later GAD. It suggests that an adequate maternal bond is an essential component of psychological health.
Despite conservation discourses in Madagascar increasingly emphasizing the role of customary institutions for wildlife management, we know relatively little about their effectiveness. Here, we used semi-structured interviews with 54 adults in eight villages to investigate whether sacred caves and taboos offer conservation benefits for cave-dwelling bats in and around Tsimanampetsotsa National Park, south-west Madagascar. Although some caves were described as sites of spiritual significance for the local communities, most interviewees (c. 76%) did not recognize their present-day sacred status. Similarly, only 22% of the interviewees recognized taboos inhibiting bat hunting and consumption. Legal protection of bats and caves through protected areas was often more widely acknowledged than customary regulations, although up to 30% of the interviewees reported consumption of bats within their communities. Guano extraction was often tolerated in sacred caves in exchange for economic compensation. This may benefit bat conservation by creating incentives for bat protection, although extraction is often performed through destructive and exploitative practices with little benefit for local communities. In view of these results our study questions the extent to which sacred sites, taboos and protected areas offer protection for bats in Madagascar. These results support previous studies documenting the erosion of customary institutions in Madagascar, including the loss of the spiritual values underpinning sacred sites. Given that many Malagasy bats are cave-dwelling species and that most depend on the customary protection of these sites, it is important to obtain a better understanding of the complex interactions between spiritual practices, taboos and protected areas in sustaining bat diversity.
The present investigation focused on evaluating the effects of different amounts of precipitates on tension and hardness properties of a Ti–6Al–4V alloy, for this, two sets of samples with bimodal and equiaxed microstructures were obtained by heat treatment process. After this, the samples were aged at 545 °C for holding times of 100 and 200 h. Observation of the aged samples in the scanning electron microscope revealed fine α2 (Ti3Al) particles precipitating in the α matrix of the alloy. Uni-axial tension tests and Vickers microhardness measurements were conducted on the unaged and aged samples. Experimental results show that ultimate strength and hardness of bimodal and equiaxed microstructures are significantly affected by the heat treatment applied to produce such microstructures. Also, it was found that the precipitation of α2 particles drastically reduced the plastic response of the Ti–6Al–4V alloy.
Imazapyr and imazamox are frequently applied postemergence to control grass and broadleaf weeds in imidazolinone-resistant sunflower in Argentina. Herbicide carryover to rotational crops represents a disadvantage of these herbicides, particularly in regions with low rainfall during the months prior to rotational crop sowing. Between 2009 and 2012, field and greenhouse studies were conducted on four important sunflower-cropped areas of Argentina. The objective was to quantify the effects of imazapyr alone and imazamox plus imazapyr applied in sunflower crops on the subsequent establishment, growth, and yield of barley, oat, and wheat. In all field experiments, imazapyr alone and imazamox plus imazapyr were applied at recommended rates (80 gha–1 and 66 plus 30 gha–1, respectively), and also, in some experiments, at double the recommended rates. Soil bioassays were also conducted in the greenhouse to study the effect of these herbicides on barley, oat, and wheat seedlings. The mixture of imazamox plus imazapyr was safer for rotational crops than imazapyr applied alone, because of the reduced rate of imazapyr in the mixture treatments. Barley was more sensitive to imidazolinones, particularly imazapyr, than the other winter cereals. Imazapyr at double rate (160 gha–1) reduced barley yield by 45% when seeds were sown 165 d after herbicide application and with 240 mm rainfall after herbicide application.
Although there is increasing evidence for the effects on wildlife of primary infrastructure (paved roads and human settlements), the effect of secondary infrastructure (tracks and isolated buildings) is generally assumed to be low in sparsely developed areas. We hypothesized that secondary infrastructure may have a negative effect similar to that of primary infrastructure, and hence may be the source of extended impacts in landscapes that are otherwise relatively undisturbed. We studied multi-year breeding site data for a community of large birds (raptors and storks) in the Monfragüe Biosphere Reserve, in the south-west Iberian Peninsula. Using a bootstrap model selection approach we modelled the distribution of breeding sites, using as predictors measures of habitat accessibility (relief, hydrography) and various types of infrastructure (primary and secondary) at different scales. Distance effect functions were developed. Secondary infrastructure exerted a negative effect on breeding sites that was equivalent to that of primary infrastructure, in terms of both transport (track vs road) and dwellings (scattered vs aggregated). The negative effect was distance (rather than density) mediated, and remained within the 1 km scale. The potential impact of secondary infrastructure is greater than that of primary infrastructure as it occupies more extensive areas and includes richer communities, with significant proportions of threatened populations. Our results contradict common assumptions about the negligible impact of secondary infrastructure on biodiversity, reveal new challenges for biodiversity conservation, and provide insights relevant for the spatial planning of isolated buildings and tracks in sparsely developed areas with species of conservation interest.
Underutilized crops tend to harbor high levels of genetic diversity, be maintained on-farm in small-scale farming systems and be relatively neglected by formal research and development strategies, including breeding programs. While high genetic variability allows these crops to adapt to marginal environments, inappropriate management practices and reductions in population sizes in individual farmers’ plots may lead to productivity loss and poor harvests. This situation further limits their cultivation and use, notwithstanding the potential these crops may hold for diversification of agricultural systems, food security and market development. Peru hosts a wealth of native agrobiodiversity, which includes many underutilized crops. To improve their performance and promote their continued conservation and use, a participatory breeding program was developed on five underutilized crops of the Peruvian highlands; the breeding approach, based on a combination of evolutionary and participatory methods, is designed to achieve a balance between yield improvement and maintenance of genetic diversity. Preliminary results in quinoa and amaranth are encouraging, fostering further engagement of farmers by increasing availability of quality seed for downstream uses. However, methodological, financial and institutional issues need to be addressed for the effort to be expanded and upscaled. This paper provides an overall description of the initiative as well as a discussion on early results obtained in quinoa and amaranth, highlighting those aspects that make this approach particularly relevant for minor crops and identifying the opportunities and challenges for the initiative to move forward.
During 2004 to 2008, weed surveys were conducted in 373 wheat fields of two different cropped areas (southwest [SW] and southeast [SE]) of the southern region of Buenos Aires Province of Argentina where different weed communities were expected because of changes in cropping practices over time, including tillage, crop sequence, fertilizers, and herbicides applied. Weed communities differed between regions, with greater numbers of native species for the SW. Weed community diversity was also greater for the SW region, probably due to the more diverse land use that resulted in greater landscape heterogeneity. Rush skeletonweed, sand rocket, yellow starthistle and turnipseed occurred at higher constancy (proportion of fields in which a given species is present) in the SW region, whereas common chickweed, false bishop's weed, corn speedwell, and common lambsquarters were present more frequently in the SE region. Compared with the 1982 survey, constancy of weeds increased, but those species with high constancy in 1982 were also with high constancy in the recent surveys. Diversity (species richness) was greater in conventional than in a no-tillage system. The constancy of Italian ryegrass, sand rocket, and yellow starthistle was lower under no-till than conventional tillage. Surveys allow identification of changes in weed community related to different agricultural systems. Rotation of crops and livestock avoid the homogenization of the environment at the landscape level. Management strategies will be necessary to prevent the increase of weeds populations' size, preserving plant diversity and the properties of the agroecosystem.
We present extensive pseudopotential density functional theory calculations dedicated to analyze the stability, electronic properties, and structural isomerism in Cu6 clusters. We consider structures of different symmetries and charge states. Our total energy calculations reveal a strong competition between two- and three-dimensional atomic arrays, the later being mostly energetically preferred for the anionic structures. The bond lengths and electronic spectra strongly depend on the local atomic environment, a result that is expected to strongly influence the catalytic activity of our clusters. Using the nudged elastic band method we analyze the interconversion processes between different Cu6 isomers. Complex atomic relaxations are obtained when we study the transition between different cluster structures; however relatively small energy barriers of approximately 0.3 eV accompany the atomic displacements. Interestingly, we obtain that by considering positively charged Cu6+ systems we reduce further the energy barriers opposing the interconversion process. The previous results could imply that, under a range of experimental conditions, it should be possible to observe different Cu6cluster structures in varying proportions.
The domestic dog is the reservoir host of Leishmania infantum, the causative agent of zoonotic visceral leishmaniasis endemic in Mediterranean Europe. Targeted control requires predictive risk maps of canine leishmaniasis (CanL), which are now explored. We databased 2187 published and unpublished surveys of CanL in southern Europe. A total of 947 western surveys met inclusion criteria for analysis, including serological identification of infection (504, 369 dogs tested 1971–2006). Seroprevalence was 23 2% overall (median 10%). Logistic regression models within a GIS framework identified the main environmental predictors of CanL seroprevalence in Portugal, Spain, France and Italy, or in France alone. A 10-fold cross-validation approach determined model capacity to predict point-values of seroprevalence and the correct seroprevalence class (<5%, 5–20%, >20%). Both the four-country and France-only models performed reasonably well for predicting correctly the <5% and >20% seroprevalence classes (AUC >0 70). However, the France-only model performed much better for France than the four-country model. The four-country model adequately predicted regions of CanL emergence in northern Italy (<5% seroprevalence). Both models poorly predicted intermediate point seroprevalences (5–20%) within regional foci, because surveys were biased towards known rural foci and Mediterranean bioclimates. Our recommendations for standardizing surveys would permit higher-resolution risk mapping.
Group testing is a procedure in which groups that contain several units (plants) are analysed without having to inspect individual plants, with the purpose of estimating the prevalence of genetically modified plants (adventitious presence of unwanted transgenic plants, AP) in a population at a low cost, without losing precision. When pool (group) testing is used to estimate the proportion of AP (p), there are several procedures that can be used for computing the confidence interval (CI); however, they usually do not ensure precision in the estimation of p. This research proposes a formula for determining the required number of pools (g), given a pool size (k), for estimating the proportion of AP plants using the Dorfman model. The proposed formula ensures precision in the estimated proportion of AP because it guarantees that the width (W) of the CI will be equal to, or narrower than, the desired width (ω), with a probability of γ. This probability accounts for the stochastic nature of the sample variance of p. We give examples to show how to use the proposed sample-size formula. Simulated data were created and tables are presented showing the different scenarios that a researcher may encounter. The Monte Carlo method was used to study the coverage and the level of assurance achieved by the proposed sample sizes. An R program that reproduces the results in the tables and makes it easy for the researcher to create other scenarios is given in the Appendix.