The last two decades have seen important advances in our knowledge of maize domestication, thanks in part to the contributions of genetic data. Genetic studies have provided firm evidence that maize ...was domesticated from Balsas teosinte (Zea mays subspecies parviglumis), a wild relative that is endemic to the mid- to lowland regions of southwestern Mexico. An interesting paradox remains, however: Maize cultivars that are most closely related to Balsas teosinte are found mainly in the Mexican highlands where subspecies parviglumis does not grow. Genetic data thus point to primary diffusion of domesticated maize from the highlands rather than from the region of initial domestication. Recent archeological evidence for early lowland cultivation has been consistent with the genetics of domestication, leaving the issue of the ancestral position of highland maize unresolved. We used a new SNP dataset scored in a large number of accessions of both teosinte and maize to take a second look at the geography of the earliest cultivated maize. We found that gene flow between maize and its wild relatives meaningfully impacts our inference of geographic origins. By analyzing differentiation from inferred ancestral gene frequencies, we obtained results that are fully consistent with current ecological, archeological, and genetic data concerning the geography of early maize cultivation.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Conservation of crop wild relatives (CWR) has always been predicated on the promise of new and useful traits, and thus modern genetics and genomics tools must help fulfill the promise and continue to ...secure the conservation of these resources. However, the vast genetic potential present in CWR is often difficult to tap, as identification of superior alleles can be hampered by the effects of the environment on expression of these alleles and masked in different genetic backgrounds; transfer of superior alleles into breeding pools to create new crop varieties can be slow and expensive. Some crop species have been more amenable to introgression of traits from wild relatives than others. In some cases, these species may be less diverged from their wild ancestors, which become a good source of mono‐ to oligogenic traits, many of which are more qualitative in nature, and sometimes of quantitative traits. Sunflower (Helianthus annuus L.) is an introgression success story, and many traits, including cytoplasmic male sterility, herbicide tolerance, drought and biotic stress resistance, and modified fatty acid profiles, have been introgressed into the cultivated gene pool from wild relatives without depression of oil yield and quality. Others, including maize (Zea mays L.), have shown little progress in widening the cultivated gene pool using exotic sources due to temporary yield depression, potential for loss of quality, and disturbance of current logistical habits. Here, we review the breeding history of sunflower and maize and explore variables that have limited the use of CWR in some species and allowed success in others. Surprisingly, in both sunflower and maize, biological limitations are similar and smaller than expected and appear to be surmountable with sufficient determination. Possible new technologies and policies to allow a deeper mining of these genetic resources in all crop species are discussed.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Background
Controversy exists regarding the way alcohol use is associated with vascular structure and arterial stiffness parameters. The purpose of this study is to evaluate the association between ...alcohol consumption with vascular structure and arterial stiffness in an adult population.
Methods
We conducted a cross‐sectional study. Five hundred and one participants were recruited by random sampling from an urban population of 43,946 individuals aged 35 to 75 years, assigned from 5 healthcare centers located in Salamanca, Spain. This was a subanalysis of the EVA study. Arterial stiffness was assessed by measuring cardio‐ankle vascular index (CAVI) and brachial‐ankle pulse wave velocity (ba‐PWV) with the VaSera VS‐1500® device, and carotid‐femoral pulse wave velocity (cf‐PWV) with the Sphygmocor®. Vascular structure was evaluated by measuring the carotid intima–media thickness (c‐IMT) with a Sonosite Micromax® ultrasound. Alcohol consumption was calculated using a standardized questionnaire and quantified in g/wk.
Results
In the multiple regression analysis adjusted for sex, age, smoking status, and systolic blood pressure, the c‐IMT and cf‐PWV values of individuals drinking > 70 g/wk were higher than those of the reference group (nondrinkers) by 0.02 mm (p = 0.030) and 0.42 m/s (p = 0.021), respectively. The association between alcohol consumption with vascular structure and arterial stiffness only attains statistical significance for cf‐PWV (p = 0.039) and c‐IMT (p = 0.019), showing an association which suggests a J‐shaped association. This association was not statistically significant for ba‐PWV and CAVI (p = 0.446 and p = 0.141, respectively), although a similar trend was observed with ba‐PWV.
Conclusions
The results of this study suggest that heavy alcohol consumption (>70 g/wk) is associated with increased c‐IMT and cf‐PWV. Moreover, we found a J‐shaped association between alcohol consumption and c‐IMT and cf‐PWV values as markers of vascular structure and arterial stiffness, with no association with ba‐PWV and CAVI being observed.
The results of this study address a topical issue, the association that chronic alcohol use can have on the development of cardiovascular disease and specifically on intermediate markers in the development of atherosclerosis. Moderate alcohol consumption (≤ 30 g/week) is associated with better values of vascular structure (carotid intima‐media thickness) and arterial stiffness (carotid‐femoral pulse wave velocity).
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Inbreeding depression is the reduction in fitness and vigor resulting from mating of close relatives observed in many plant and animal species. The extent to which the genetic load of mutations ...contributing to inbreeding depression is due to large-effect mutations versus variants with very small individual effects is unknown and may be affected by population history. We compared the effects of outcrossing and self-fertilization on 18 traits in a landrace population of maize, which underwent a population bottleneck during domestication, and a neighboring population of its wild relative teosinte. Inbreeding depression was greater in maize than teosinte for 15 of 18 traits, congruent with the greater segregating genetic load in the maize population that we predicted from sequence data. Parental breeding values were highly consistent between outcross and selfed offspring, indicating that additive effects determine most of the genetic value even in the presence of strong inbreeding depression. We developed a novel linkage scan to identify quantitative trait loci (QTL) representing large-effect rare variants carried by only a single parent, which were more important in teosinte than maize. Teosinte also carried more putative juvenile-acting lethal variants identified by segregation distortion. These results suggest a mixture of mostly polygenic, small-effect partially recessive effects in linkage disequilibrium underlying inbreeding depression, with an additional contribution from rare larger-effect variants that was more important in teosinte but depleted in maize following the domestication bottleneck. Purging associated with the maize domestication bottleneck may have selected against some large effect variants, but polygenic load is harder to purge and overall segregating mutational burden increased in maize compared to teosinte.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
IntroductionSleep problems are a growing public health concern being related, among others, to an increased risk of cardiovascular diseases or worse cognitive functioning. In addition, they can ...affect aspects related to personal motivation and quality of life. However, very few studies have analysed the possible determinants of sleep quality in the adult population as a whole, establishing patterns based on these determinants.The objectives are to evaluate the determinants of sleep quality in a representative sample of the general adult population between 25 and 65 years old, and to establish patterns of sleep quality based on lifestyles, psychological factors, morbidities, sociodemographic variables, biological markers and other possible determinants.Methods and analysisDescriptive observational cross-sectional study. The study population will include a representative sample of 500 people between 25 and 65 years old from the cities of Salamanca and Ávila (Spain) selected by random sampling stratified by age groups and sex. A 90-minute visit will be performed, during which sleep quality will be assessed. The variables collected will be: morbidity, lifestyles (physical activity, diet, toxic habits), psychological factors (depression, stress, occupational stress and anxiety), socioeconomic and work-related variables, habitability conditions of the habitual residence and rest area, screen time, relaxation techniques and melatonin as a biological marker related to sleep quality.DiscussionWith the results of this work, improved interventions for behaviour modification could be designed, as well as intervention and education programmes or other research aimed at improving sleep quality.Ethics and disseminationThis study has a favourable opinion from the Ethics Committee for Drug Research of the Health Areas of Salamanca and Ávila (CEim Code: PI 2021 07 815). The results of this study will be published in international impact journals of different specialties.Trial registration numberNCT05324267.
Aim
The aim of this study was to evaluate the effectiveness of an intensive intervention led by primary care nurses for lifestyle modification among people with intermediate cardiovascular risk.
...Background
Cardiovascular diseases may be prevented by adopting healthy lifestyles. Interventions focused on populations at risk are more efficient than those aimed at the general population. More than 50 per cent of cardiovascular events occur in people with intermediate cardiovascular risk, but only a few studies have targeted this population.
Design
A randomized controlled trial approved in January 2017.
Methods
We will recruit 208 participants aged 35–74 years who have intermediate cardiovascular risk. They will be selected by consecutive sampling and will be randomized into a control group or intervention group. Individual standardized brief counselling on healthy lifestyles will be provided to both groups. Additionally, individuals from the intervention group will receive four weekly group sessions focusing on cardiovascular risk, healthy diet, moderation in alcohol consumption, daily physical activity, stress management and smoking cessation and two motivational follow‐up calls. The primary outcome will be the lifestyle modification measured by total steps recorded by a pedometer, total score on the Mediterranean Diet Adherence Screener and percentage of current smokers.
Discussion
This study will allow us to investigate whether an intensive intervention based on a multifactorial group approach is more effective in lifestyle modification than individual standardized brief counseling among adults with intermediate cardiovascular risk. Our results could lead to the establishment of new strategies for cardiovascular risk management.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK, VSZLJ
The objective of this work was to evaluate the capability of artificial neural networks (ANN) to predict shelf life and the acidity on vacuum packed fresh cheese. First, cheese samples, of 200 g per ...unit, were prepared; then these samples were stored for 2 to 4 days at temperatures of 4, 10 and 16 ° C and relative humidity of 67.5%. Throughout the storage, the acidity (AC) and sensorial acceptability were determined; this acceptability was used to determine the Shelf life time (SLT) by modified Weibull sensory risk method. A set of artificial neural networks (ANN) was created and trained; temperatures (T), maturation time (M) and failure possibility (F(x)) were used as inputs and SLT and AC as outputs. From this set, the networks with the lowest mean squared error (MSE) and best fit (R2) were selected. These networks showed correlation coefficients (R2) of 0.9996 and 0.6897 for SLT and AC respectively, and good accuracy compared with regression models. It is shown that the ANN can be used to adequately model the SLT and, to a lesser degree, the AC of vacuum-packed fresh cheeses.
Seed Dormancy in Mexican Teosinte Avendano Lopez, Adriana Natividad; Jesus Sanchez Gonzalez, Jose de; Ruiz Corral, Jose Ariel ...
Crop science,
September 2011, Volume:
51, Issue:
5
Journal Article
Peer reviewed
Seed dormancy in wild Zea species may affect fitness and relate to ecological adaptation. The primary objective of this study was to characterize the variation in seed germination of the wild species ...of the genus Zea that currently grow in México and to relate this variation to their ecological zones of adaptation. In addition, we compared methods to break dormancy and measured the germination responses of seeds to environment factors that are related to seasonal changes. Teosinte populations representing all the taxonomic and racial groups known in México were collected during the period 2003 to 2008 in twelve states of México. Seed dormancy was classified according to the rate of its loss (depth of dormancy). Results indicated that more than 90% of populations studied had some degree of seed dormancy. Nondormant populations are distributed predominantly in semicold areas, while deep and very deep seed dormancy was found in populations distributed in hot and very hot environments in well defined geographic regions of the Balsas River Basin and in San Felipe Usila, Oaxaca. Mechanical seed scarification was the best method to break dormancy.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Analysis of fine scale genetic structure in continuous populations of outcrossing plant species has traditionally been limited by the availability of sufficient markers. We used a set of 468 SNPs to ...characterize fine-scale genetic structure within and between two dense stands of the wild ancestor of maize, teosinte (Zea mays ssp. parviglumis). Our analyses confirmed that teosinte is highly outcrossing and showed little population structure over short distances. We found that the two populations were clearly genetically differentiated, although the actual level of differentiation was low. Spatial autocorrelation of relatedness was observed within both sites but was somewhat stronger in one of the populations. Using principal component analysis, we found evidence for significant local differentiation in the population with stronger spatial autocorrelation. This differentiation was associated with pronounced shifts in the first two principal components along the field. These shifts corresponded to changes in allele frequencies, potentially due to local topographical features. There was little evidence for selection at individual loci as a contributing factor to differentiation. Our results demonstrate that significant local differentiation may, but need not, co-occur with spatial autocorrelation of relatedness. The present study represents one of the most detailed analyses of local genetic structure to date and provides a benchmark for future studies dealing with fine scale patterns of genetic diversity in natural plant populations.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Este trabajo analiza la incidencia de la Responsabilidad Social Corporativa Interna (RSCI) en el desempeño empresarial en el momento posterior a la pandemia del Covid 19. El estudio se enfoca en un ...sector que ha experimentado una gran evolución y cambio en la mentalidad y costumbres de los clientes, el inmobiliario. Se ha trabajado con una muestra de 109 empresas, a quienes se les ha presentado un cuestionario, tratado con la técnica de los modelos de ecuaciones estructurales. Los resultados del estudio nos indican que la RSCI tiene una influencia positiva y directa sobre la elección del cliente. Esta, a su vez, incide igualmente en la satisfacción del mismo, al igual que ésta en el performance del sector. Podemos afirmar que la RSCI es una fuente de ventaja competitiva de indudable valor y presentará Implicaciones para el sectary su gestión.
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CEKLJ, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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