13 research outputs found

    Molecular and phenotypic characterization of a collection of white grain sorghum [Sorghum bicolor (L.) Moench] for temperate climates

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    AbstractSorghum [Sorghum bicolor (L.) Moench] is a subsistence crop and the main food for populations in arid or semiarid regions and it is appreciated for the production of gluten-free products, forages, raw materials for industrial transformation and packaging. The end-use of different sorghum purposes having various plant or kernel characteristics require specific breeding programs to develop the desired ideotype. Sorghum grains can be classified according to kernel color, tannins and polyphenols content: white, yellow, red, brown, and black. White sorghum is characterized by a low level of total phenolic content and tannins. The advantage of using white sorghum is: increased protein digestibility, nutritional composition and consumer acceptance similar to other cereals. A collection of 117 white grain sorghums was characterized using 10 SSRs and preliminary agronomic observations were made for main traits. SSR analysis revealed from 10 to 33 alleles per locus.Observed heterozygosity was lower than expected according to the reproduction system of sorghum. Phylogenetic analysis revealed 6 main groups of genotypes. Only one group is constituted by genotypes with the same geographical origin (Egypt) while other groups are admixtures of different countries. The principal coordinate analysis revealed good correspondence between genetic profiles and groups evidenced by similar agronomic performances

    The Rediscovery of Traditional Maize Agrobiodiversity: A Study Case from Northern Italy

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    Nowadays, agriculture is under the pressure of climate change and new pathogen outbreaks while farmers are requiring breeders to develop more resistant and resilient genotypes. The genetic base for breeding may be increased through appropriate conservation, description and characterization of local varieties and germplasm collections that have never been used in breeding, and which could be sources of useful alleles. In this framework, the present paper focuses on eight maize landraces of the eastern part of Emilia-Romagna, derived from the Italian maize collection sampled in 1954. Landraces are characterized by a short cycle length and different kernel types—mainly flint-like or an intermediate type of yellow or yellow–orange color—while dent landraces are less represented. Pigmented and white corns are absent even though one landrace (Va213) showed the presence of scattered blue kernels on yellow ears. Ear shape is frequently conical, a trait associated with drought-resistance and common in Italian traditional landraces. Genetic characterization was carried out on 529 individuals by using 10 SSR markers. A total of 68 different alleles, ranging from 4 for markers (phi084 and umc1401) to 11 (phi031) and from 27 (Va217) to 50 (Va211), were evidenced at the individual and population level. AMOVA analysis revealed a small amount (19%) of variability between populations, as supported also by PCoA, with the only exception of Va217, which is different from the others, as evidenced also by phylogenetic analysis. Population structure analysis resulted in the identification of three and four population levels, which are consistent with previous results

    Morphological and Genetic Characterization of Local Maize Accessions from Emilia Romagna Region, Italy

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    Italian maize germplasm is particularly rich in local materials and each region is characterized by the presence of peculiar local varieties deriving from centuries of adaptation, selection and cultivation. While the introduction of hybrids, during the 1950s, led to the disappearing of many of these varieties, some have been maintained in cultivation by farmers, frequently in marginal areas, as a kind of family heritage. Local varieties were identified throughout field surveys carried out in recent years. The discovery of a traditional popcorn variety over the most common flint and semi-flint materials used for production of polenta was interesting. Since these varieties have never been adequately described and reported in scientific literature, this study was aimed to solve this lack of knowledge on recently discovered local maize populations. Characterization represents the first step of a process focused on the preservation and possible exploitation of important genetic resources. Traditional materials are a useful reservoir of genes for adaptation to local conditions and climate changes. Adequate breeding programs can use such germplasm for developing new and more resilient varieties. These local materials have been characterized at the morphological level highlighting plant, ear and kernel differences. Genetic characterization, carried out on 455 individuals by the use of 10 SSR markers, revealed 62 different alleles ranging from four for markers phi127, phi076 and phi084 to nine for marker p-bnlg176. The landraces are well distinguishable at genetic level since 40% of genetic variability is present among accessions. Five landraces are characterized by the presence of private alleles and heterozygosity levels are generally good. These findings support the possibility to correctly preserve local materials through in situ conservation. Phylogenetic analysis evidenced the presence of varietal clusters, the clearest one formed by three red-pigmented accessions. STRUCTURE analysis revealed that five landraces have a well-defined genetic attribution while the remaining two (EMR04-Mais Rosso di Rasora and EMR10-Mais del Principe di Scavolino) are both constituted by two different backgrounds

    MEMS Gradiometers for Attitude Determination on CubeSats

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    This paper presents the design, fabrication and testing of a new high sensitivity gravity sensor for attitude determination in CubeSats. The project is a collaboration between the Institute for Gravitational Research at the University of Glasgow and Ă…AC-Clyde. The gravitational gradiometer takes advantages of the technology of microelectromechanical systems (MEMS) and determines the attitude of the satellite by a differential gravity measurement, the principle at the base of gravitational gradiometry. The capacitive readout allows to measure the rotation of the MEMS gradiometer and consequently evaluate the angle changes of the CubeSat. The developed geometry consists of two symmetrical masses connected to a fixed support by four thin flexure hinges. The all-Silicon sensor resonates at a frequency of 6 Hz, and has a total mass of less than 2 g. It is expected that the sensor geometry and the readout demonstrated would be suitable to achieve the performances required from CubeSat systems and detect a rotation of the small satellite of 1 degree, in order to offer performance comparable to other state-of-the-art sensors currently available on the market

    Machine Learning Strategies to Improve Cross-Subject and Cross-Session Generalization in EEG-Based Emotion Recognition: A Systematic Review

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    A systematic review on machine-learning strategies for improving generalization in electroencephalography-based emotion classification was realized. In particular, cross-subject and cross-session generalization was focused. In this context, the non-stationarity of electroencephalographic (EEG) signals is a critical issue and can lead to the Dataset Shift problem. Several architectures and methods have been proposed to address this issue, mainly based on transfer learning methods. In this review, 418 papers were retrieved from the Scopus, IEEE Xplore, and PubMed databases through a search query focusing on modern machine learning techniques for generalization in EEGbased emotion assessment. Among these papers, 75 were found eligible based on their relevance to the problem. Studies lacking a specific cross-subject or cross-session validation strategy, or making use of other biosignals as support were excluded. On the basis of the selected papers’ analysis, a taxonomy of the studies employing Machine Learning (ML) methods was proposed, to gether with a brief discussion of the different ML approaches involved. The studies with the best results in terms of average classification accuracy were identified, supporting that transfer learning methods seem to perform better than other approaches. A discussion is proposed on the impact of (i) the emotion theoretical models and (ii) psychological screening of the experimental sample on the classifier performances

    Morphological and Genetic Characterization of Local Maize Accessions from Emilia Romagna Region, Italy

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    Italian maize germplasm is particularly rich in local materials and each region is characterized by the presence of peculiar local varieties deriving from centuries of adaptation, selection and cultivation. While the introduction of hybrids, during the 1950s, led to the disappearing of many of these varieties, some have been maintained in cultivation by farmers, frequently in marginal areas, as a kind of family heritage. Local varieties were identified throughout field surveys carried out in recent years. The discovery of a traditional popcorn variety over the most common flint and semi-flint materials used for production of polenta was interesting. Since these varieties have never been adequately described and reported in scientific literature, this study was aimed to solve this lack of knowledge on recently discovered local maize populations. Characterization represents the first step of a process focused on the preservation and possible exploitation of important genetic resources. Traditional materials are a useful reservoir of genes for adaptation to local conditions and climate changes. Adequate breeding programs can use such germplasm for developing new and more resilient varieties. These local materials have been characterized at the morphological level highlighting plant, ear and kernel differences. Genetic characterization, carried out on 455 individuals by the use of 10 SSR markers, revealed 62 different alleles ranging from four for markers phi127, phi076 and phi084 to nine for marker p-bnlg176. The landraces are well distinguishable at genetic level since 40% of genetic variability is present among accessions. Five landraces are characterized by the presence of private alleles and heterozygosity levels are generally good. These findings support the possibility to correctly preserve local materials through in situ conservation. Phylogenetic analysis evidenced the presence of varietal clusters, the clearest one formed by three red-pigmented accessions. STRUCTURE analysis revealed that five landraces have a well-defined genetic attribution while the remaining two (EMR04-Mais Rosso di Rasora and EMR10-Mais del Principe di Scavolino) are both constituted by two different backgrounds

    Reproducible Assessment of Valence and Arousal Based on an EEG Wearable Device

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    An electroencephalography-based detection system of emotional states exploiting few dry channels is proposed. The circumplex model of affect was the reference theory adopted and the standardized dataset International Affective Picture System IAPS was exploited for emotion elicitation. A subset of stimuli polarized on both the valence and the arousal dimension was employed to maximize the effectiveness of the emotion induction. A Self-Assessment Manikin (SAM) was submitted to the subjects after each image to assess the valence and arousal scores of the target emotion. The agreement between the two measures, namely the IAPS scores and the SAM scores was verified through a Bland Altman analysis and a Spearman correlation analysis. An initial screening of the sample allowed to manage the bias caused by depressive and anxiety disorders. The proposed system was experimentally validated. 9 healthy subjects participated in the experimental activity and their EEG signals were acquired through an 8-channel headset. As a result, the best accuracy in the within-subject case of 62.5 ± 4.89 % for the valence dimension and of 66.67 ± 11.88 % for the arousal dimension, was obtained. The poor correlation emerged between IAPS scores and SAM scores negatively impacts on the accuracy and highlights the issue of IAPS update

    Efficacy of Denosumab Therapy Following Treatment with Bisphosphonates in Women with Osteoporosis: A Cohort Study

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    Denosumab is a human monoclonal antibody that neutralizes RANKL, a cytokine able to interact with the RANK receptor on preosteoclasts and osteoclasts, decreasing their recruitment and differentiation, leading to a decreased bone resorption. The aim of this observational real-life study was to analyze adherence to denosumab therapy and assess its efficacy in increasing bone mineral density (BMD) and modulating biochemical skeletal markers following previous treatments with bisphosphonates in a group of post-menopausal women with osteoporosis. Women were recruited in the specialized center from March 2012 to September 2019. Biochemical markers were recorded at baseline and every six months prior to subsequent drug injection. Dual X-ray absorptiometry was requested at baseline and after 18/24 months. Comparing BMD at baseline and after denosumab therapy in naive patients and in those previously treated with bisphosphonates, a positive therapeutic effect was observed in both groups. The results of our real-life study demonstrate, as expected, that BMD values significantly increased upon denosumab treatment. Interestingly, denosumab showed an increased efficacy in patients previously treated with bisphosphonates. Moreover, biochemical markers data indicate that osteoporotic patients, without other concomitant unstable health conditions, could be evaluated once a year, decreasing the number of specialistic center access

    Epigenetic stability in Saffron (Crocus sativus L.) accessions during four consecutive years of cultivation and vegetative propagation under open field conditions

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    Saffron (Crocus sativus L.) is a sterile species that is vegetatively propagated in the field, year by year, via the production of new corms. While Saffron\u2019s genetic variability is extremely low, phenotypic variation is frequently observed in the field and epigenetics could be a possible origin of these alternative phenotypes. Present day knowledge on Saffron epigenetics is very low or absent. In the present paper, to deepen existing knowledge, we focused on the epigenetic differences and stability among 17 Saffron accessions, of different geographic origin, during four consecutive years of vegetative propagation under open field conditions. Before the analysis, the selected accessions have been cultivated in the same field for at least three consecutive years. Despite the low genetic variability and the prolonged co-cultivation in the same environment, Methylation-Sensitive Amplified Fragment Length Polymorphism (MS-AFLP) analysis revealed a very high epigenetic difference among accessions, making it possible to discriminate them based on the epigenetic profiles. During the four years of the study, a little variation has been observed within accessions following different patterns, slightly modifying the accession epigenotypes but not enough to even them to a more uniform profile. These results confirm that, under natural conditions, Saffron epigenotypes are highly stable, supporting a role for epigenetics in phenotypic variability
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