Optimizing irrigation and determining the most sensitive development stage to drought in barley (Hordeum vulgare L.) in a semi-arid environment

Rising temperatures and increasing water scarcity, which are already important issues, are expected to intensify in the near future due to global warming. Optimizing irrigation in agriculture is a challenge. Understanding the response of crop development stages to water deficit stress provides an opportunity for optimizing irrigation. Here we studied the response of two barley varieties (Rihane, Martin), to water deficit stress at three development stages (tillering, stem elongation, and heading) by measuring water status and grain yield components in a field experiment in Tunisia. The three stages were selected due to their importance in crop growth and grain development. Water deficit stress was initiated by withholding water for 21 days at the three stages with subsequent re-watering. Water deficit led to a progressive decrease in leaf water potential. In both varieties, heading was the stage most sensitive to water deficit. Leaf water potential measurements indicated that water deficit stress was more severe during heading, which to some extent may have influenced the comparison between growth stages. During heading, the number of ears per plant and weight of a thousand grains were reduced by more than 70% and 50%, respectively compared with stress at tillering. Comparison of yield components showed differences between the two barley varieties only when the water deficit was produced during the tillering stage

A mindfulness-based intervention pilot easibility study for elementary school students with severe learning difficulties : effects on internalized and externalized symptoms from an emotional regulation perspective

Objective. Students with severe learning disabilities often show signs of anxiety, depression, and problem behaviors such as inattention and conduct problems. Mindfulness-based interventions (MBIs) in school settings constitute a promising option to alleviate these co-occurring symptoms. This pilot study aimed to evaluate the impact of an MBI on symptoms and behaviors of elementary school students with severe learning disabilities. Method. A one-group pretest-posttest design was used. The sample comprised 14 students aged 9 to 12 years with special education needs. Both student-report and teacher-report of the Behavior Assessment System for Children, Second Edition were used. Results. Repeated-measures analyses of variance revealed a significant impact of the MBI on symptoms and behaviors such as anxiety, depression, inattention, aggression, and conduct problems. Effect sizes for all variables were considered large (partial η2 = .31-.61). Conclusion. These preliminary results indicate that MBIs can reduce the frequency of symptoms and problem behaviors often found in children with learning disabilities in elementary schools. Further multiple baseline experimental trials with a long-term follow-up are warranted to establish more robustly the effect of MBIs for children with learning disabilities

Interest of First Laparoscopy in the Etiological Diagnosis of Isolated Exudative Ascites

The purpose of this research article was to determine the contribution of performing laparoscopy first in the etiological diagnosis of isolated exudative ascites. Our retrospective descriptive study had been performed over 15 years and included 46 patients who had undergone exploratory laparoscopy for exudative ascites. The average age of the patients was 52 years. Biological and morphological examinations contributed to making the etiological diagnosis. Therefore, diagnostic laparoscopy was indicated. Peritoneal carcinomatosis and tuberculosis were the most common causes seen in 34.2% and respectively 65.8% of cases. Visual laparoscopic diagnosis was peritoneal carcinomatosis in 16 cases and peritoneal tuberculosis in 28 cases, indecisive in one case and biliary ascites in one case. The histological diagnosis was peritoneal tuberculosis in 24 cases and peritoneal carcinomatosis in 12 cases and there were 9 cases of rare diagnoses. Peritoneal biopsies were negative in 2 cases for which the etiological diagnoses were kidney failure in one case and hypothyroidism in the other case. The postoperative recovery was simple in 42 cases (91.3%). The complications were: an accidental rupture of the left diaphragmatic dome in one case (2.1%), gastrointestinal bleeding in the immediate postoperative period in two cases (4.2%) and infected ascites in one case (2.1%). The post-operative scapular pain was reported in 4.2% of our patients. Operative mortality in our patients was nil. The overall care had an average cost of 1685.7 dinars for each of our patients, with extremes ranging from 1055.7 to 3605.7 dinars. For patients with isolated exudative ascites that should have been explored through laparoscopy first, the average cost would be 130.1 dinars, with a material gain for each of 1555.6 dinars. This attitude could also allow a reduction in the mean hospital stay (which was 27 days to few days) associated with early treatment. Our study confirms the interest in laparoscopy first with peritoneal biopsies as part of the etiological diagnosis of isolated exudative ascites

Catechol-O-Methyltransferase (COMT) Val(108/158 )Met polymorphism does not modulate executive function in children with ADHD

BACKGROUND: An association has been observed between the catechol-O-methyltransferase (COMT) gene, the predominant means of catecholamine catabolism within the prefrontal cortex (PFC), and neuropsychological task performance in healthy and schizophrenic adults. Since several of the cognitive functions typically deficient in children with Attention Deficit Hyperactivity Disorder (ADHD) are mediated by prefrontal dopamine (DA) mechanisms, we investigated the relationship between a functional polymorphism of the COMT gene and neuropsychological task performance in these children. METHODS: The Val(108/158 )Met polymorphism of the COMT gene was genotyped in 118 children with ADHD (DSM-IV). The Wisconsin Card Sorting Test (WCST), Tower of London (TOL), and Self-Ordered Pointing Task (SOPT) were employed to evaluate executive functions. Neuropsychological task performance was compared across genotype groups using analysis of variance. RESULTS: ADHD children with the Val/Val, Val/Met and Met/Met genotypes were similar with regard to demographic and clinical characteristics. No genotype effects were observed for WCST standardized perseverative error scores [F(2,97 )= 0.67; p > 0.05], TOL standardized scores [F(2,99 )= 0.97; p > 0.05], and SOPT error scores [F(2,108 )= 0.62; p > 0.05]. CONCLUSIONS: Contrary to the observed association between WCST performance and the Val(108/158 )Met polymorphism of the COMT gene in both healthy and schizophrenic adults, this polymorphism does not appear to modulate executive functions in children with ADHD

Synthèse et modélisation quantique de pérovskite à base de stannate substituée par des métalloïdes

Transparent conductive oxides (TCO) are one of the main components of current optoelectronic devices such as light-emitting diodes, flat screens, touch screens and photovoltaic devices. They constitute an unusual class of materials combining two antithetic physical properties, high optical transparency in the ultraviolet-visible region (E_g> 3 eV) and high electrical conductivity, which can reach 〖10〗^4 S.〖cm〗^(-1). The uniqueness of these materials as well as the diversity of their applications motivate researchers, experimenters and theorists, to design new efficient ones. Nowadays, n-type TCOs are the subject of a rich literature while it is not the case of the p-type TCOs. A reason could be found in the localized nature of the O(2p) states. The absence of this kind of material hinders the development of transparent p-n junction.The goal of this thesis is to develop a new p-type perovskite Sr〖Sn〗_(1-x) M_x O_3 substituted by metalloids such as Al, Ga and In with a high-performance transparent conductive properties. Our methodology was to correlate an experimental study of synthesis and characterization to a theoretical investigation of structural, electronic and thermodynamic properties based on density functional theory (DFT). This approach allowed us to evaluate the performance of our materials according to the nature of the metalloid and its ratio so that, in fine, we will be able to guide the synthesis towards more efficient materials.Keywords: transparent conducting oxide, p-type TCO, perovskiteSr〖Sn〗_(1-x) M_x O_3, metalloids, Sol gel and solid-state reaction synthesis, DFT.Les oxydes transparents conducteurs (TCO) sont impliqués dans les principaux dispositifs optoélectroniques actuels comme les diodes électroluminescentes, les écrans plats, les écrans tactiles ou encore les dispositifs photovoltaïques. Ces matériaux constituent une classe inhabituelle de matériaux alliant deux propriétés physiques antithétiques, une haute transparence optique dans la région ultraviolet-visible (E_g>3 eV) et forte conductivité électrique, qui peut atteindre 〖10〗^4 S.〖cm〗^(-1). La singularité de ces matériaux ainsi que la diversité de leurs applications motivent la communauté des chercheurs, expérimentateurs et théoriciens, à en concevoir de nouveaux de plus en plus de nouveaux matériaux performants. De nos jours, les TCO de type n, font l’objet d’une littérature riche tandis que ceux de type p sont beaucoup moins développés en raison de la nature très localisée des orbitales O(2p) au niveau de Fermi. L’absence de ce type de semi-conducteur de conductivité freine, entre autre, le déploiement de jonctions p-n transparents.L'objectif de cette thèse a été est de proposer de nouveaux oxydes pérovskites de type pérovskitesSr〖Sn〗_(1-x) M_x O_3 substitués par des métalloïdes de la colonne 13 (M = Al, Ga et In) pouvant être à la fois transparents et semi-conducteurs de type p. Notre méthodologie consistait à corréler une l’étude de synthèse et caractérisations expérimentales de synthèse et caractérisations à des calculs de modélisation de propriétés structurales, électroniques et thermodynamiques basées sur la théorie de la fonctionnelle de densité (DFT). Cette approche nous a permis, par des calculs, d’évaluer les performances des nos matériaux à synthétiser en fonction de la nature et du ratio taux du substituant pour et de pouvoir in fine orienter la synthèse vers de matériaux encore plus prometteurs.Mots-clés: Oxyde transparent conducteur, TCO de type p, pérovskite Sr〖Sn〗_(1-x) M_x O_3, métalloïdes, synthèse Sol gel et céramique, DFT

Synthesis and quantum simulation of stannates based perovskites sustituted by metalloids

Les oxydes transparents conducteurs (TCO) sont impliqués dans les principaux dispositifs optoélectroniques actuels comme les diodes électroluminescentes, les écrans plats, les écrans tactiles ou encore les dispositifs photovoltaïques. Ces matériaux constituent une classe inhabituelle de matériaux alliant deux propriétés physiques antithétiques, une haute transparence optique dans la région ultraviolet-visible (E_g>3 eV) et forte conductivité électrique, qui peut atteindre 〖10〗^4 S.〖cm〗^(-1). La singularité de ces matériaux ainsi que la diversité de leurs applications motivent la communauté des chercheurs, expérimentateurs et théoriciens, à en concevoir de nouveaux de plus en plus de nouveaux matériaux performants. De nos jours, les TCO de type n, font l’objet d’une littérature riche tandis que ceux de type p sont beaucoup moins développés en raison de la nature très localisée des orbitales O(2p) au niveau de Fermi. L’absence de ce type de semi-conducteur de conductivité freine, entre autre, le déploiement de jonctions p-n transparents.L'objectif de cette thèse a été est de proposer de nouveaux oxydes pérovskites de type pérovskitesSr〖Sn〗_(1-x) M_x O_3 substitués par des métalloïdes de la colonne 13 (M = Al, Ga et In) pouvant être à la fois transparents et semi-conducteurs de type p. Notre méthodologie consistait à corréler une l’étude de synthèse et caractérisations expérimentales de synthèse et caractérisations à des calculs de modélisation de propriétés structurales, électroniques et thermodynamiques basées sur la théorie de la fonctionnelle de densité (DFT). Cette approche nous a permis, par des calculs, d’évaluer les performances des nos matériaux à synthétiser en fonction de la nature et du ratio taux du substituant pour et de pouvoir in fine orienter la synthèse vers de matériaux encore plus prometteurs.Mots-clés: Oxyde transparent conducteur, TCO de type p, pérovskite Sr〖Sn〗_(1-x) M_x O_3, métalloïdes, synthèse Sol gel et céramique, DFT.Transparent conductive oxides (TCO) are one of the main components of current optoelectronic devices such as light-emitting diodes, flat screens, touch screens and photovoltaic devices. They constitute an unusual class of materials combining two antithetic physical properties, high optical transparency in the ultraviolet-visible region (E_g> 3 eV) and high electrical conductivity, which can reach 〖10〗^4 S.〖cm〗^(-1). The uniqueness of these materials as well as the diversity of their applications motivate researchers, experimenters and theorists, to design new efficient ones. Nowadays, n-type TCOs are the subject of a rich literature while it is not the case of the p-type TCOs. A reason could be found in the localized nature of the O(2p) states. The absence of this kind of material hinders the development of transparent p-n junction.The goal of this thesis is to develop a new p-type perovskite Sr〖Sn〗_(1-x) M_x O_3 substituted by metalloids such as Al, Ga and In with a high-performance transparent conductive properties. Our methodology was to correlate an experimental study of synthesis and characterization to a theoretical investigation of structural, electronic and thermodynamic properties based on density functional theory (DFT). This approach allowed us to evaluate the performance of our materials according to the nature of the metalloid and its ratio so that, in fine, we will be able to guide the synthesis towards more efficient materials.Keywords: transparent conducting oxide, p-type TCO, perovskiteSr〖Sn〗_(1-x) M_x O_3, metalloids, Sol gel and solid-state reaction synthesis, DFT

Pre, peri and postnatal complications in children with attention deficit hyperactivity disorder : a family study

Genetic and non-shared environmental factors (factors experienced by one child to the exclusion of his siblings) have been strongly implicated in the aetiology of Attention Deficit Hyperactivity Disorder (ADHD). Shared environmental factors were not implicated. Pregnancy, labour/delivery and neonatal complications (PLDNC) were often associated to ADHD. However, no investigations aimed at delineating the shared/non-shared nature of these factors were reported. In order to identify PLDNC which are more likely to be non-shared, we recruited 65 children with ADHD and assessed their history for PLDNC. 45 of them had non-affected siblings that were also assessed for PLDNC. Compared to their non-affected siblings, ADHD children had significantly higher neonatal complications (p = 0.01). Furthermore, neonatal complications were associated with higher motor activity (p = 0.04) and attention deficits (p = 0.03) in ADHD diagnosed children, suggesting that neonatal complications are more likely to be non-shared environmental factors of etiological relevance to ADHD