961 resultados para ENRICHMENT
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Keratoconus, a common inherited ocular disorder resulting in progressive corneal thinning, is the leading indication for corneal transplantation in the developed world. Genome-wide association studies have identified common SNPs 100 kb upstream of ZNF469 strongly associated with corneal thickness. Homozygous mutations in ZNF469 and PR domain-containing protein 5 (PRDM5) genes result in brittle cornea syndrome (BCS) Types 1 and 2, respectively. BCS is an autosomal recessive generalized connective tissue disorder associated with extreme corneal thinning and a high risk of corneal rupture. Some individuals with heterozygous PRDM5 mutations demonstrate a carrier ocular phenotype, which includes a mildly reduced corneal thickness, keratoconus and blue sclera. We hypothesized that heterozygous variants in PRDM5 and ZNF469 predispose to the development of isolated keratoconus. We found a significant enrichment of potentially pathologic heterozygous alleles in ZNF469 associated with the development of keratoconus (P = 0.00102) resulting in a relative risk of 12.0. This enrichment of rare potentially pathogenic alleles in ZNF469 in 12.5% of keratoconus patients represents a significant mutational load and highlights ZNF469 as the most significant genetic factor responsible for keratoconus identified to date.
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One of the main applications of serum proteomics is the identification of new biomarkers for animal disease or animal production. However, potential obstacles to these studies are the poor performance of affinity serum depletion methods based on human antigens when using animal samples, and loss of minor serum components bound to albumin and other proteins. In the present study, we have analyzed the efficiency and reproducibility of the ProteoMiner® beads with bovine and porcine serum samples, and compared to a traditional immunoaffinity-based albumin and IgG depletion system specific for human samples. The ProteoMiner kit is based on the use of a combinatorial peptide binding library and intends to enrich low-abundance proteins.
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Implications Provision of environmental enrichment in line with that required by welfare-based quality assurance schemesdoes not always appear to lead to clear improvements in broiler chicken welfare. This research perhaps serves to highlightthe deficit in information regarding the ‘real world’ implications of enrichment with perches, string and straw bales.
Introduction Earlier work showed that provision of natural light and straw bales improved leg health in commercial broilerchickens (Bailie et al., 2013). This research aimed to determine if additional welfare benefits were shown in windowedhouses by increasing straw bale provision (Study 1), or by providing perches and string in addition to straw bales (Study 2).
Material and methods Commercial windowed houses in Northern Ireland containing ~23,000 broiler chickens (placed inhouses as hatched) were used in this research which took place in 2011. In Study 1 two houses on a single farm wereassigned to one of two treatments: (1) 30 straw bales per house (1 bale/44m2), or (2) 45 straw bales per house (1bale/29m2). Bales of wheat straw, each measuring 80cm x 40cm x 40cm were provided from day 10 of the rearing cycle,as in Bailie et al. (2013). Treatments were replicated over 6 production cycles (using 276,000 Ross 308 and Cobb birds),and were swapped between houses in each replicate. In Study 2, four houses on a single farm were assigned to 1 of 4treatments in a 2 x 2 factorial design. Treatments involved 2 levels of access to perches (present (24/house), or absent), and2 levels of access to string (present (24/house), or absent), and both types of enrichment were provided from the start of thecycle. Each perch consisted of a horizontal, wooden beam (300 cm x 5 cm x 5cm) with a rounded upper edge resting on 2supports (15 cm high). In the string treatment, 6 pieces of white nylon string (60 cm x 10 mm) were tied at their mid-pointto the wire above each of 4 feeder lines. Thirty straw bales were also provided per house from day 10. This study wasreplicated over 4 production cycles using 368,000 Ross 308 birds. In both studies behaviour was observed between 0900and 1800 hours in weeks 3-5 of the cycle. In Study 1, 8 focal birds were selected in each house each week, and generalactivity, exploratory and social behaviours recorded directly for 10 minutes. In Study 2, 10 minute video recordings weremade of 6 different areas (that did not contain enrichment) of each house each week. The percentage of birds engaged inlocomotion or standing was determined through scan sampling these recordings at 120 second intervals. Four perches andfour pieces of string were filmed for 25 mins in each house that contained these enrichments on one day per week. The totalnumber of times the perch or string was used was recorded, along with the duration of each bout. In both studies, gaitscores (0 (perfect) to 5 (unable to walk)) and latency to lie (measured in seconds from when a bird had been encouraged tostand) were recorded in 25 birds in each house each week. Farm and abattoir records were also used in both studies todetermine the number of birds culled for leg and other problems, mortality levels, slaughter weights, and levels of pododermatitis and hock burn. Data were analysed using SPSS (version 20.0) and treatment and age effects on behaviouralparameters were determined in normally distributed data using ANOVA (‘Straw bale density*week’, or‘string*perches*week’ as appropriate), and in non-normally distributed data using Kuskall-Wallace tests (P<0.05 forsignificance) . Treatment (but not age) effects on performance and health data were determined using the same testsdepending on normality of data.
Results Average slaughter weight, and levels of mortality, culling, hock burn and pododermatitis were not affected bytreatment in either study (P<0.05). In Study 1 straw bale (SB) density had no significant effect on the frequency orduration of behaviours including standing, walking, ground pecking, dust bathing, pecking at bales or aggression, or onaverage gait score (P>0.05). However, the average latency to lie was greater when fewer SB were provided (30SB 23.38s,45SB 18.62s, P<0.01). In Study 2 there was an interaction between perches (Pe) and age in lying behaviour, with higherpercentages of birds observed lying in the Pe treatment during weeks 4 and 5 (week 3 +Pe 77.0 -Pe 80.9, week 4 +Pe 79.5 -Pe 75.2, week 5 +Pe 78.4 -Pe 76.2, P<0.02). There was also a significant interaction between string (S) and age inlocomotory behaviour, with higher percentages of birds observed in locomotion in the string treatment during week 3 butnot weeks 4 and 5 (week 3 +S 4.9 -S 3.9, week 4 +S 3.3 -S 3.7, week 5 +S 2.6 -S 2.8, P<0.04). There was also aninteraction between S and age in average gait scores, with lower gait scores in the string treatment in weeks 3 and 5 (week3: +S 0.7, -S 0.9, week 4: +S 1.5, -S 1.4, week 5: +S 1.9, -S 2.0, P<0.05). On average per 25 min observation there were15.1 (±13.6) bouts of perching and 19.2 (±14.08) bouts of string pecking, lasting 117.4 (±92.7) and 4.2 (±2.0) s for perchesand string, respectively.
Conclusion Increasing straw bale levels from 1 bale/44m2 to 1 bale/29m2 floor space does not appear to lead to significantimprovements in the welfare of broilers in windowed houses. The frequent use of perches and string suggests that thesestimuli have the potential to improve welfare. Provision of string also appeared to positively influence walking ability.However, this effect was numerically small, was only shown in certain weeks and was not reflected in the latency to lie.Further research on optimum design and level of provision of enrichment items for broiler chickens is warranted. Thisshould include measures of overall levels of activity (both in the vicinity of, and away from, enrichment items).
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Neste trabalho foi efectuada uma avaliação integrada usando descritores sedimentares e biológicos ao nível da espécie e da comunidade e índices bióticos de síntese para o traçamento do enriquecimento orgânico numa região, com características dispersivas, da costa Oeste de Portugal. Na área estudada existem gradientes ambientais e biológicos relacionados com a heterogeneidade da paisagem sedimentar, a qual inclui sedimentos desde areias finas limpas a vasas. Contudo, na área próxima do emissário, esta paisagem é mais homogénea e constituída por areia fina com baixo teor em finos. Nesta região, alguns dos descritores estudados deram uma indicação coerente de alterações ambientais associadas ao enriquecimento orgânico. O potencial de oxidação - redução mostrou valores negativos até 250 m do emissário, o que indicia que a degradação da matéria orgânica que entra no sistema cria condições reduzidas no sedimento. Os isótopos estáveis de carbono e azoto no sedimento diferenciam a área mais próxima do emissário, que apresenta uma depleção de acordo com uma origem terrestre da matéria orgânica naquela parte da plataforma. Uma imagem similar foi obtida pela análise dos isótopos estáveis na macrofauna que diagnosticou a origem terrestre da matéria orgânica consumida. A composição específica e a abundância das comunidades bentónicas também são significativamente diferentes junto ao emissário, onde são dominadas por espécies oportunistas, tolerantes ao enriquecimento orgânico. No entanto, os índices bióticos em validação no âmbito da implementação da Directiva Quadro da Água, não foram eficientes a mostrar as alterações bentónicas associadas ao enriquecimento orgânico apesar de alguns índices se basearem nos limiares de tolerância/sensibilidade a este tipo de perturbação. Apesar deste caso de estudo reflectir um enriquecimento orgânico moderado, uma vez que não foram detectadas alterações sedimentares ou acumulação de matéria orgânica, nem um significativo empobrecimento das comunidades biológicas junto ao emissário, a análise ao nível dos índices bióticos de síntese pode levar à perda de informação essencial e, portanto, prejudicar a nossa capacidade de diagnóstico devendo ser usados com cuidado. A análise do conjunto de dados da composição específica forneceu uma imagem mais precisa da perturbação ambiental e descritores específicos, tais como os isótopos estáveis, permitiram uma melhor compreensão da extensão espacial do enriquecimento orgânico.
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Alterations of freshwater flow regimes and increasing eutrophication lead to alterations in light availability and nutrient loading into adjacent estuaries and coastal areas. Phytoplankton community respond to these changes in many ways. Harmful phytoplankton blooms, for instance, may be a consequence of changes in nutrient supply, as well as the replacement of some phytoplankton species (like diatoms, that contribute for the development of large fish and shellfish populations) by ohers (like cyanobacteria, that may be toxic and represent an undesirable food source for higher trophic levels). Nutrient and light enrichment experiments allow us to understand and predict the effects of eutrophication on the growth of phytoplankton. This is a fundamental tool in water management issues, since it enables the prediction of changes in the phytoplankton community that may be harmful to the whole ecosystem, and the design of mitigation strategies (Zalewski 2000).
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The synthesis of cDNA from RNA is challenging due to the inefficiency of reverse transcription (RT). In order to address this, a method was developed known as RT-Bst for sequential RT of RNA and Bst DNA polymerase amplification for enrichment of cDNA in a single tube reaction. Using genomic RNA from bacteriophage MS2, the yield of cDNA produced by RT alone and RT-Bst were compared by analysis of PCR-amplified products. Using random primers a superior performance was observed when amplifying MS2 RNA following RT-Bst compared to RT alone, indicating that greater quantities of cDNA were present after RT-Bst. RT-Bst was also compared with RT alone for their relative ability to produce sufficient cDNA to amplify 8 target regions spanning the respiratory syncytial virus (RSV) genome. Six out of 8 targets were amplified consistently by PCR subsequent to RT-Bst amplification whereas only 3 out of 8 targets could be amplified after RT alone. RSV sequences were selectively amplified using RSV specific primers from a mixed template containing an excess of MS2 RNA in a RT-Bst reaction without amplifying MS2 sequences. This suggests that RT-Bst can be used to amplify RNA sequences non-specifically using random primers and specifically using sequence specific primers and enhances the yield of cDNA when compared to RT alone.
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Microalgae are promising microorganisms for the production of food and fine chemicals. Several species of microalgae are used in aquaculture with the purpose of transfer bioactive compounds up to the aquatic food chain. The main objective of this project was to develop a stress–inducement strategy in order to enhance the biochemical productivity of Nannochloropsis gaditana, Rhodomonas marina and Isochrysis sp. for aquaculture purposes having in account their growth and organizational differences. In this regard, two experiments were design: the first one consisted on the alteration of overall nutrient availabilities in growth medium; and the second one comprised changes in nitrogen and sulfur concentrations maintaining the concentrations of the other nutrients present in a commercial growth medium (Nutribloom plus), which is frequently used in aquaculture. Microalgae dried biomass was characterized biochemically and elemental analysis was also performed for all samples. In first experimental design: linear trends between nutrient availability in growth media and microalgae protein content were obtained; optimum productivities of eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) were attained for both R. marina and N. gaditana in growth media enriched with 1000 L L-1 of nutrient solution whereas for Isochrysis sp. the double of Nutribloom plus was needed; the decrease of glucans and total monosaccharides with nutrient availability for R. marina and Isochrysis sp. showed the occurrence of a possible depletion of carbohydrates towards lipids and proteins biosynthesis. Second experimental desing: N. gaditana exhibited the highest variation in their biochemical composition against the applied perturbation; variations observed for microalgae in their biochemical composition were reflected in their elemental stoichiometry; in N. gaditana the highest nitrogen concentrations lead to overall maximum productivities of the biochemical parameters. The results of the present work show two stress-inducement strategies for microalgae that may constitute a base for further investigations on their biochemical enhancement.
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This study evaluated a preschool parent enrichment programme to assess if child and parent involvement in the programme facilitated the children's subsequent school adjustment. Also examined were the programme's effects on parent-child relationships. Participants were 56 Junior-Senior Kindergarten and Grade One students from one elementary school. Parent participants were 12 parents from the preschool parent enrichment programme, 6 parents whose children had attended other preschool programmes, and 6 parents whose children had remained at home prior to school. Five elementary teachers and both nursery school teachers from the parent enrichment programme also participated. Measures used included the Florida Key to assess children's inferred self-concept as learner and four subscales (relating, asserting, coping and investing), and interviews to assess parent and teacher perceptions. Findings indicated that there was little difference between parent and teacher perceptions about children who had attended a preschool programme. Both groups showed improved social, emotional, and behavioural skill development, together with increased self-esteem, and the ability to cope with separation from their parents. This enabled children to make the transition from preschool to primary school more successful. Children from the parent enrichment programme were not readily identifiable in terms of the profile promulgated for disadvantaged children. The Florida Key showed a main effect for the coping subscale, indicating that children from the parent enrichment programme may show more confidence in their abilities, and seek assistance from teachers than children who had no preschool experience. The parent enrichment programme appeared to have the biggest impact on the parents. Parents reported improved relationships with their children, increased confidence and self-esteem, as well as improved parenting and general life skills. The implications for short-term gains for children from this type of programme are better readiness for school, more positive self-esteem, improved social behaviour, and a higher achievement motivation. The long-term gains for children are predicted to be fewer special education placements, less grade retention, and a lower dropout rate from school. The short-term gains for parents are better social support networks," greater self-confidence, better interactions with children, and improved parenting skills. The long-term benefits may be an increased motivation to continue education, gain employment, and less family breakdown and abuse.
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Introduction: Chez les mammifères, la naissance de nouveaux neurones se poursuit à l’âge adulte dans deux régions du cerveau: 1) l’hippocampe et 2) la zone sous-ventriculaire du prosencéphale. La neurogenèse adulte n’est pas un processus stable et peut être affectée par divers facteurs tels que l’âge et la maladie. De plus, les modifications de la neurogenèse peuvent être à l’origine des maladies de sorte que la régulation ainsi que le rétablissement de la neurogenèse adulte doivent être considérés comme d’importants objectifs thérapeutiques. Chez la souris saine ou malade, la neurogenèse hippocampale peut être fortement régulée par l’enrichissement environnemental ainsi que par l’activité physique. Cependant, lors même que l’activité physique et l’enrichissement environnemental pourraient contribuer au traitement de certaines maladies, très peu d’études porte sur les mécanismes moléculaires et physiologiques responsables des changements qui sont en lien avec ces stimuli. Objectifs et hypothèses: Les principaux objectifs de cette étude sont de caractériser les effets de stimuli externes sur la neurogenèse et, par le fait même, d’élucider les mécanismes sous-jacents aux changements observés. En utilisant le modèle d’activité physique volontaire sur roue, cette étude teste les deux hypothèses suivantes: tout d’abord 1) qu’une période prolongée d’activité physique peut influencer la neurogenèse adulte dans le prosencéphale et l’hippocampe, et 2) que l’activité volontaire sur roue peut favoriser la neurogenèse à travers des stimuli dépendants ou indépendants de la course. Méthodes: Afin de valider la première hypothèse, nous avons utilisé un paradigme incluant une activité physique volontaire prolongée sur une durée de six semaines, ainsi que des analyses immunohistochimiques permettant de caractériser l’activité de précurseurs neuronaux dans la zone sous-ventriculaire et l’hippocampe. Ensuite, pour valider la seconde hypothèse, nous avons utlisé une version modifiée du paradigme ci-dessous, en plaçant les animaux (souris) soit dans des cages traditionnelles, soit dans des cages munies d’une roue bloquée soit dans des cages munies d’une roue fonctionnelle. Résultats: En accord avec la première hypothèse, l’activité physique prolongée volontaire a augmenté la prolifération des précurseurs neuronaux ainsi que la neurogenèse dans le gyrus dentelé de l’hippocampe comparativement aux animaux témoins, confirmant les résultats d’études antérieures. Par ailleurs, dans ce paradigme, nous avons aussi observé de la prolifération acrue au sein de la zone sous-ventriculaire du prosencéphale. De plus, en accord avec la seconde hypothèse, les souris placées dans une cage à roue bloquée ont montré une augmentation de la prolifération des précurseurs neuronaux dans l’hippocampe comparable à celle observée chez les souris ayant accès à une roue fonctionnelle (coureurs). Cependant, seuls les animaux coureurs ont présenté une augmentation de la neurogenèse hippocampale. Conclusions: Ces résultats nous ont permis de tirer deux conclusions nouvelles concernant les effets de l’activité physique (course) sur la neurogenèse. Premièrement, en plus de la prolifération et de la neurogenèse dans le gyrus dentelé de l’hippocampe, la prolifération dans la zone sous-ventriculaire du prosencéphale peut être augmentée par l’activité physique sur roue. Deuxièmement, l’environnement dans lequel l’activité physique a lieu contient différents stimuli qui peuvent influencer certains aspects de la neurogenèse hippocampale en l’absence d’activité physique sur roue (course).
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The present study is an attempt to standardize the environmental condition like pH, salinity and photoperiod, and also the feed for the maximum production of rotifers. Considering the deficiency of essential fatty acids in rotifers, enrichment experiments were carried out and fatty acids profile were analysed. Attempts were made to improve the production of clown fish (Amphiprion sebae) juveniles using enriched rotifers. Attempts were also made to rear various larval stages of Penaeus monodon with enriched rotifers as a substitute for Artemia nauplii.
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Concentrations and distributions of trace metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in surficial sediments of the Cochin backwaters were studied during both monsoon and pre-monsoon periods. Spatial variations were in accordance with textural charaterstics and organic matter content. A principal component analysis distinguished three zones with different metal accumulation capacity: (i) highest levels in north estuary, (ii) moderate levels in central zone, and (iii) lowest levels in southern part. Trace metal enrichments are mainly due to anthropogenic contribution of industrial, domestic, and agricultural effluents, whose effect is enhanced by settling of metals due to organic flocculation and inorganic precipitation associated with salinity changes. Enrichments factors using Fe as a normalizer showed that metal contamination was the product of anthropogenic activities. An assessment of degree of pollution-categorized sediments as moderately polluted with Cu and Pb, moderately-to-heavily polluted with Zn, and heavily-to-extremely polluted with Cd. Concentrations at many sites largely exceed NOAA ERL (e.g., Cu, Cr, and Pb) or ERM (e.g., Cd, Ni, and Zn). This means that adverse effects for benthic organisms are possible or even highly probable.
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Little is known about the bacterial ecology of evaporative salt-mining sites (salterns) of which Teguidda-n-Tessoumt at the fringe of the West-African Saharan desert in Niger is a spectacular example with its many-centuries-old and very colorful evaporation ponds. During the different enrichment steps of the salt produced as a widely traded feed supplement for cattle, animal manure is added to the crude brine, which is then desiccated and repeatedly crystallized. This study describes the dominant Bacteria and Archaea communites in the brine from the evaporation ponds and the soil from the mine, which were determined by PCR-DGGE of 16S rDNA. Correspondence analysis of the DGGE-community fingerprints revealed a change in community structure of the brine samples during the sequential evaporation steps which was, however, unaffected by the brine's pH and electric conductivity (EC). The Archaea community was dominated by a phylogenetically diverse group of methanogens, while the Bacteria community was dominated by gamma proteobacteria. Microorganisms contained in the purified salt product have the potential to be broadly disseminated and are fed to livestock across the region. In this manner, the salt mines represent an intriguing example of long-term human activity that has contributed to the continual selection, cultivation, and dissemination of cosmopolitan microorganisms.
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Proporciona una gran cantidad de recursos para animar a los niños superdotados a disfrutar de su potencial. Las actividades pueden ser utilizadas dentro y fuera del aula. Todas son fotocopiables y van acompañadas de soluciones y notas para los maestros Los recursos se dividen en varios temas: inglés, alfabetización, matemáticas, ciencias, humanidades, ciudadanía, resolución de problemas, toma de decisiones y procesamiento de la información; lenguas extranjeras, los niños pequeños, el pensamiento lógico, el trabajo de detective y los códigos; pensamiento lateral (forma específica de organizar los procesos de pensamiento, que busca una solución mediante estrategias que normalmente serían ignoradas por el pensamiento lógico), concursos. Cada tema va precedido por un comentario, esboza los vínculos curriculares y dan una orientación general para los maestros.