898 resultados para test-day milk yield


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Scan circuit generally causes excessive switching activity compared to normal circuit operation. The higher switching activity in turn causes higher peak power supply current which results into supply, voltage droop and eventually yield loss. This paper proposes an efficient methodology for test vector re-ordering to achieve minimum peak power supported by the given test vector set. The proposed methodology also minimizes average power under the minimum peak power constraint. A methodology to further reduce the peak power below the minimum supported peak power, by inclusion of minimum additional vectors is also discussed. The paper defines the lower bound on peak power for a given test set. The results on several benchmarks shows that it can reduce peak power by up to 27%.

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Kirjallisuuskatsauksessa käsiteltiin viiliä hapanmaitotuotteena, viilin arviointimenetelmiä sekä viilihapatteissa käytettyjen hapatekantojen vaikutuksia maidossa ja niiden vuorovaikutuksia toisiinsa. Lisäksi pohdittiin viilihapatteiden bakteriofaageja, niiden ehkäisyä sekä solunsisäisiä että -ulkoisia faagiresistenssimekanismeja. Kokeellisessa osassa tutkittiin, onko nykyisten tuotantohapatteiden koostaminen yksittäiskannoista mahdollista, sekä koostettiin uusista Lactococcus lactis ssp. cremoris -kannoista varahapate. Hapatteiden käyttökelpoisuutta tutkittiin rakennemittauksin ja aistinvaraisin menetelmin. Varahapatteen faagikestävyyttä testattiin valmistamalla viiliä ja infektoimalla viilit faaginäytteillä. Hapatekannat viljeltiin fermentorissa, konsentroitiin sentrifugoimalla ja pakastettiin –75 °C:ssa. Hapatteet koostettiin noin 1 päivä ennen viilin valmistusta. Viilit arvioitiin aistinvaraisesti 3–6 hengen ryhmässä ja viileille tehtiin rakennemittaukset (kiinteys, sakeus ja koossapysyvyys) sekä kemialliset analyysit. Aistinvaraisen arvioinnin tulokset käsiteltiin tilastollisesti ja tulosten perusteella tehtiin uudet kantakombinaatiot ja viilit. Tuotantohapatekannoilla valmistetut viilit arvioitiin kolmitestillä (n = 10–11) ja uusilla kannoilla valmistetut viilit arvioitiin profiilitestillä (n = 8). Lisäksi viileille tehtiin rakennemittaukset ja kemialliset analyysit. Varahapatekoosteilla valmistettujen viilien pH laski 4,5:een faagin läsnäollessa 0–10 tunnin viiveellä verrattuna faagivapaisiin viileihin, kun taas tuotantohapatteet eivät hapantuneet faagin läsnäollessa. Aromintuottajat eivät kasvaneet viileissä kunnolla, kun hapate koostettiin yksittäiskannoista. Kolmitestissä ei erotettu nykyisillä tuotantohapatteilla valmistettua viiliä yksittäin koostetusta hapatteesta, eli hapatteita on mahdollista koostaa yksittäiskannoista. Varahapatteilla koostetut viilit poikkesivat profiilitestissä tuotantohapatteella koostetusta viilistä ulkonäkö- ja rakenneominaisuuksiltaan. Makuominaisuuksien suhteen ei viilien välille saatu eroa.

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In the present paper, the constitutive model is proposed for cemented soils, in which the cementation component and frictional component are treated separately and then added together to get overall response. The modified Cam clay is used to predict the frictional resistance and an elasto-plastic strain softening model is proposed for the cementation component. The rectangular isotropic yield curve proposed by Vatsala (1995) for the bond component has been modified in order to account for the anisotropy generally observed in the case of natural soft cemented soils. In this paper, the model proposed is used to predict the experimental results of extension tests on the soft cemented soils whereas compression test results are presented elsewhere. The model predictions compare quite satisfactorily with the observed response. A few input parameters are required which are well defined and easily determinable and the model uses associated flow rule.

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Revised: 2006-05

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The biomass yields of duck week (Lemna minor(L) was monitored in hydroponic media prepared by variously extracting 0.50, 1.00 and 2.00g of dried chicken manure per liter of city water (tap water) supply. The culture media consisting of aqueous extract of the various manure treatments were made up to 12 liters in all cases with tap water as control. Plastic baths of 25 liters capacity with 0.71 super(m2) surface area were used as culture facility. Each bath was stocked at a density of 30g super(m-2) with fresh weed samples (i.e 21.30g/bath). Maximum yields were obtained at all treatment levels and control on day 3 and based on the highest yield of 0.37gm super(-2)d super(-1) (dry matter) obtained at 1.00gL manure treatment which was however not significantly higher (P>0.05) than the 0.36gm super(-2)d super(-1) (dry matter) at 0.05gl super(-1) media manure content, an average manure level of 0.75l super(-1) was selected and used to determine the operational plant density. Thus fresh weights of 30 to 300gm super(-2) was grown in triplicate at 30g intervals for a period of 3 days. A regression equation of Y=2.6720+0.0021x with a corresponding maximum density or operational plant density of 266gm super(-2) and yield of 0.98gm super(-2), d super(-1) (dry matter) were obtained. Further growth trials were carried out at the operational density and manure levels of 0.50, 0.75, 1.00, 1.25, 1.50, 1.75 and 2.00gl super(-1) media manure concentration giving a significantly higher yield (P<0.05) of 17gm super(-2), d super(-1) (dry matter). This yield was however doubled to between 2.21 and 2.24gm super(-2) d super(-1) (equivalent to 7.96 to 8.06mt.ha-1, Yr-1 dry matter on extrapolation) if 25% and 75% respectively of the total weed cover were harvested daily within the experimental period. The role of some dissolved plant nutrients (DPN) were also discussed

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Este trabalho teve como objetivos identificar e analisar fatores associados ao aleitamento materno exclusivo, com significância estatística, em crianças menores de quatro meses residentes em Juiz de Fora, Minas Gerais. Fornece informações básicas para planejamento de política de amamentação neste município, estudando fatores influentes no desmame e criando Banco de Dados em Aleitamento Materno no Centro de Computação do Núcleo de Assessoria Técnica aos Estudos em Saúde da Universidade Federal de Juiz de Fora, disponível pára uso público. Compara os resultado desta pesquisa aos de outras cidades brasileiras com estudo de metodologia semelhante. Para atingir os objetivos propostos foi realizada pela autora desta tese uma pesquisa no período de 10 de agosto a 13 de setembro de 2002, época da campanha de vacinação na cidade, em uma amostra por conglomerado, tendo sido entrevistadas 1859 pessoas, sendo 625 mães e acompanhantes de crianças menores de 4 meses, em 24 postos de vacinação. A terminologia empregada deu-se de acordo com a recomendação da OMS (1991). Aplicou-se um questionário por intermédio de 268 entrevistadores voluntários, previamente treinados, incluindo estudantes da área de saúde. A pesquisa fez parte de um estudo multicêntrico em conjunto com o Núcleo de Pesquisas Epidemiológicas em Nutrição e Saúde da Universidade de São Paulo e do Núcleo de Investigação em Saúde da Mulher e da Criança, Instituto de Saúde, Secretaria Estadual de Saúde de São Paulo denominado Avaliação das práticas alimentares no primeiro ano de vida em dias nacionais de vacinação. A análise dos dados foi processada utilizando-se o programa Statiscal Package for The Social Sciences (SPSS) e os resultados foram descritos utilizando-se o teste do qui-quadrado para verificar a significância estatística da associação dos fatores independentes com o fator de desfecho aleitamento materno exclusivo. Para estudar possíveis fatores de confusão foi aplicada a técnica de análise de regressão logística. A pesquisa evidenciou que a prevalência de Aleitamento Materno Exclusivo aos 4 meses é baixa, sendo que esta é menor que as taxas da maioria das capitais brasileiras, com exceção de Cuiabá. Os hábitos de usar chupetas e mamadeiras são muito freqüentes no município. Os fatores de risco para interrupção do aleitamento materno exclusivo até os quatro meses encontrados foram: primiparidade, nascimento em hospital público ou público-privado, não disponibilidade para amamentar, uso de chupetas ou mamadeiras. A maioria das crianças inicia a amamentação no primeiro dia de vida em casa mas não de forma exclusiva. À medida que a idade aumenta, o índice de amamentação vai diminuindo progressivamente, indicando a necessidade urgente de programas de apoio e incentivo ao aleitamento materno, em especial de sua forma exclusiva, bem como de promoção do mesmo no município. Deve ser dada ênfase nesta atenção às mulheres primíparas e àquelas mulheres cujos partos ocorreram em hospitais públicos ou públicos-privados, que não tenham disponibilidade para amamentar e que utilizam mamadeiras ou chupetas para seus filhos.

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Sorbitol é um poliol encontrado em produtos para fins especiais, como diet e light, Dentro deste contexto, incluem-se as lactantes como grandes consumidoras, almejando o retorno mais rápido ao peso pré-gestacional. Devido à grande carência em dados referentes às consequências metabólicas do consumo excessivo destes tipos de produtos, o objetivo deste trabalho foi avaliar os possíveis efeitos da ingestão materna de sorbitol na lactação sobre os perfis nutricional, bioquímico e toxicológico nas proles amamentadas. O teste da Salmonella/microssoma foi utilizado, inicialmente, na avaliação mutagênica e citotóxica com linhagens de S. enterica sorovar Typhimurium (TA97, TA98, TA100, TA102, TA104 e TA1535). Verificamos a capacidade de reversão da mutação (I.M.) e sobrevivência (%), em diferentes concentrações (0,4; 4; 40; 400; 4000 e 5000 μg/placa). Os resultados foram considerados positivos para valores de I.M. ≥ 2,0. Ratas wistar lactantes (6 por grupo experimental), cada uma com 6 filhotes, receberam sorbitol (0,00015 mg/g/dia; 0,0015 mg/g/dia e 0,15 mg/g/dia), nos primeiros 14 dias da lactação. Neste período, avaliamos a biometria das mães e proles, consumo de ração e ingestão hídrica das mães. Após a lactação, as ratas mães foram ordenhadas, e, junto com as proles, sacrificadas por punção cardíaca, para coleta de sangue total. Os fígados das proles foram submetidos ao método de perfusão, para obtenção de hepatócitos em cultura primária, ao final dos 14 dias de lactação. Os fêmures das proles foram retirados, para obtenção da medula óssea. A bioquímica de sangue das proles (glicose, triglicerídeo, colesterol total, LDL, proteínas totais, albumina, ALT, AST, cálcio total e ionizado) foi analisada, assim como a bioquímica do leite ordenhado (triglicerídeos). Os testes do micronúcleo em medual óssea e hepatócitos, assim como o teste Cometa em sangue total, foram utilizados para avaliação genotóxica e citotóxica, de acordo com as diretrizes da OECD. Os resultados mostraram que, em concentrações mais baixas (0,00015 e 0,0015 mg/g), o sorbitol induziu o ganho de peso, principalmente na menor concentração (0,00015 mg/g), e alterações no perfil lipídico do sangue em todas as concentrações. As quantidades de triglicerídeo no leite variaram em função da dose ingerida, reduzida na maior concentração (0,15 mg/g) e aumentada na menor (0,00015 mg/g). A maior concentração (0,15 mg/g) resultou em perda de peso das mães e proles, diminuição de proteínas viscerais totais, albumina e aumento de enzimas hepáticas (ALT e AST) nas proles. Os resultados do teste da Salmonella/microssoma não indicaram mutagenicidade, entretanto, uma relação de dependência entre dose e Índice de Mutagenicidade (I.M.). Ambos os testes, micronúcleos de medula óssea e hepatócitos, apresentaram uma citotoxicidade dose dependente, estatisticamente significativa em relação ao grupo controle, corroborando com a genotoxicidade do teste Cometa e dependência de dose encontrada no teste da Salmonella/microssoma. Em concentrações mais baixas, parece existir modulação das vias lipogênicas, em contrapartida, nas mais altas a toxicidade parece dificultar tais alterações, induzindo o efeito contrário. Concluimos que o consumo excessivo de sorbitol resulta em alterações metabólicas e toxicológicas em lactentes, mesmo sendo considerado seguro pelo FDA e ANVISA.

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An experiment was conducted for a period of 28 days using 7-day old C. batrachus larvae of initial total length (±S.D.) of 7.4 ± 0.49 mm and weight (±S.D.) of 2.8 ± 0.75 mg. Five test diets viz. diets I, II, III, IV and V were prepared. Diet I was formulated using 30% fish meal (FM), 20% soybean meal (SM) and 20% Baker's yeast (BY), diet III using 15% FM, 20% SM, 15% cotton seed meal and 30% BY and diet IV using 20% FM, 30% BY and 30% powdered milk. The remaining two diets (diets II and V) were prepared using minced clam meat (96%) and BY (90%) respectively as the sole source of protein. Three replications were used for each treatment. The larvae fed on diet II exhibited significantly (P<0.05) better length gain and specific growth rate (SGR) than those of the larvae fed on diet III and there was no significant difference among the length gain and SGR of the larvae fed on diet I,II,IV and V. The larvae fed on diet II also showed significantly better weight gain and survival than those of the larvae fed on other diets. There was no significant difference between the condition factor of the larvae fed on diet II and IV. However, the larvae fed on diet II showed better condition factor than those of the larvae fed on other diets.

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We investigated memory impairment in newly hatched chicks following in ovo exposure to a 50-Hz magnetic field (MF) of 2 mT (60 min/day) on embryonic days 12-18. Isolated and paired chicks were used to test the effect of stress during training, and memory retention was tested at 10, 30, and 120 min, following exposure to a bitter-tasting bead (100% methylanthranilate). Results showed that memory was intact at 10 min in both isolated and paired chicks with or without MF exposure. However, while isolated chicks had good memory retention levels at 30 and 120 min, those exposed to MF did not. The results suggest a potential disruption of memory formation following in ovo exposure to MF, with this effect only evident in the more stressed, isolated chicks. Bioelectromagnetics 31:150-155, 2010. (C) 2009 Wiley-Liss. Inc.

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The classification of a concrete mixture as self-compacting (SCC) is performed by a series of empirical characterization tests that have been designed to assess not only the flowability of the mixture but also its segregation resistance and filling ability. The objective of the present work is to correlate the rheological parameters of SCC matrix, yield stress and plastic viscosity, to slump flow measurements. The focus of the slump flow test investigation was centered on the fully yielded flow regime and an empirical model relating the yield stress to material and flow parameters is proposed. Our experimental data revealed that the time for a spread of 500 mm which is used in engineering practice as reference for measurement parameters, is an arbitrary choice. Our findings indicate that the non-dimensional final spread is linearly related to the non-dimensional yield-stress. Finally, there are strong indications that the non-dimensional viscosity of the mixture is associated with the non-dimensional final spread as well as the stopping time of the slump flow; this experimental data set suggests an exponential decay of the final spread and stopping time with viscosity. © Appl. Rheol.

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穗发芽(PHS,preharvest sprouting)是影响禾本科作物生产的重要的灾害之一。收获时期如遇潮湿天气容易导致穗发芽发生。发生穗发芽的种子内部水解酶(主要是α-淀粉酶)活性急剧升高,胚乳贮藏物质开始降解,造成作物产量和品质严重降低。因此,选育低穗发芽风险的品种是当前作物育种工作中面临的重要任务。 青稞(Hordeum vulgare ssp. vulgare)主要分布于青藏高原,自古以来就是青藏高原人民的主要粮食。近年来,由于青稞丰富的营养成分和特有的保健品质、在燃料工业中的潜力以及在啤酒酿造工业中的利用前景,在发达国家日趋受到重视,掀起综合研究利用的热潮。我国拥有占全世界2/3 以上的青稞资源,具有发展青稞产业的得天独厚的条件。然而,由于青稞收获期间恰逢青藏高原雨季来临,常有穗发芽灾害发生,使青稞生产损失巨大。目前对青稞穗发芽研究很少,适用于育种的穗发芽抗性材料相对缺乏,不能很好的满足青稞穗发芽抗性育种的需要。本研究以青藏高原青稞为材料,对其穗发芽抗性的评价指标和体系进行构建,同时筛选青稞抗穗发芽品种并对其抗性进行评价,还利用分子生物学手段对青稞穗发芽抗性的分子机理进行了初步探讨。主要研究结果如下: 1. 本试验以来自于我国青藏高原地区的青稞为材料,对休眠性测定的温度范围进行探讨,并对各种穗发芽抗性测定方法的对青稞的适用性进行评测。通过探讨温度对13 个不同基因型的青稞籽粒发芽和休眠性表达的影响,对筛选青稞抗穗发芽资源的温度条件进行探索,并初步分析了其休眠性表达的机理。在10,15,20,25,30℃的黑暗条件下,选用新收获的13 个青稞品种为材料进行籽粒发芽实验,以发芽指数(GI)评价其休眠性。结果发现,不同品种对温度敏感性不同,其中温度不敏感品种,在各温度条件下均表现很低的休眠性;而温度敏感品种,其休眠性表达受低温抑制,受高温诱导。15℃至25℃是进行青稞休眠性鉴定的较适宜的温度范围。通过对供试材料发芽后的α-淀粉酶活性,发现温度对青稞种子的休眠性表达的影响至少在一定程度上表现在对α-淀粉酶活性的调控上。随后,对分别在马尔康和成都进行种植的34 份青稞穗发芽指数(SI),穗发芽率(SR),籽粒发芽指数(GI)和α-淀粉酶活性(AA)进行了测定和分析,发现它们均受基因型×栽培地点的极显著影响,且四个参数之间具有一定相关性。GI 参数由于其变异系数较低,在不同栽培地点稳定性好,且操作简便,是较可靠和理想的穗发芽评价参数。SI 参数可作为辅助,区别籽粒休眠性相似的材料(基因型)或全面评价材料(基因型)的穗发芽抗性特征。AA 参数稳定性较差,并且检测方法复杂,因此不建议在育种及大量材料筛选和评价时使用。此外,青稞穗发芽抗性受环境影响较大,评价时应考虑到尽可能多的抗性影响因素及其在不同栽培条件下的变异。 2. 对来自青藏高原的青稞穗发芽抗性特征及其与其它农艺性状间的关系进行研究。通过测定穗发芽指数(SI)、籽粒发芽指数(GI)和α-淀粉酶活性(AA),表明113 份青稞材料的穗发芽抗性具有显著差异。SI、GI 和AA 参数的变幅分别为1.00~8.86、0.01~0.97 和0.00~2.76,其均值分别为4.72、0.63 和1.22。根据SI 参数,六个基因型,包括‘XQ9-5’,‘XQ33-9’,‘XQ37-5’,‘XQ42-9’,‘XQ45-7’和‘JCL’被鉴定为抗性品种。综合SI、GI 和AA 参数,可以发现青稞的穗发芽抗性机制包含颖壳等穗部结构的抗性和种子自身的抗性(即种子休眠性),且供试材料中未发现较强的胚休眠品种,除‘XQ45-7’外,所有品种在发芽第四天均能检测出α-淀粉酶活性。穗部结构和种子休眠的抗性机制因基因型不同而不同,在穗发芽抗性中可单独作用或共同作用。农家品种和西藏群体分别比栽培品种和四川群体的穗发芽抗性强,而在不同籽粒颜色的青稞中未发现明显差异。相关性检验发现,青稞的穗发芽抗性,主要是种子休眠性,与百粒重、开花期、成熟期、穗长、芒长和剑叶长呈显著负相关关系,与株高相关性不显著。农艺性状可以作为穗发芽抗性材料选育中的辅助指标。本试验为青稞穗发芽抗性育种研究提供了必要的理论基础和可供使用的亲本材料。 3. α-淀粉酶是由多基因家族编码的蛋白质,在植物种子萌发时高度表达,与植物种子的萌发能力密切相关。在大麦种子发芽时,高等电点α-淀粉酶的活性远大于低等电点的α-淀粉酶。为了研究不同穗发芽抗性青稞品种中编码高等电点α-淀粉酶Amy1 基因结构与抗性间的关系,我们以筛选得到的抗性品种‘XQ32-5’(TR1)、‘XQ37-5’(TR2)、‘XQ45-7’(TR3),易感品种‘97-15’(TS1)、‘9657’(TS2)以及强休眠大麦品种‘SAMSON’(SAM)为材料,对其Amy1 基因的编码区序列进行克隆和结构分析,并对它们推导的氨基酸序列进行比较。结果显示,青稞Amy1 基因具有三个外显子、两个内含子,编码区中有13 个核苷酸变异位点,均位于2、3 号外显子,2 个变异位点位于2 号外显子。SAM 和TS1 分别在2 号外显子相应位置有5 个相同的碱基(GAACT)的插入片段。相应α-淀粉酶氨基酸序列推导发现,所有核苷酸变异中有8 个导致相应氨基酸残基的改变,其余位点为同义突变。青稞Amy1 基因编码区序列品种间相似度高达99%以上,部分序列变异可能与其穗发芽抗性有关。随后,我们又通过SYBR Green 荧光定量技术对该基因在不同发芽时间(1d~7d)的相对表达水平进行了差异性检测。结果发现,7 天内不能检测到SAM 的Amy1 基因表达,5 个青稞品种间的Amy1 基因的相对表达量均随着发芽时间延长而上升,但上升方式有所不同。弱抗品种该基因表达更早,转录本增加速率更大,且在4~5 天可达到平台期。发芽7 天中,抗性品种总转录水平明显低于易感品种。本研究结果表明,青稞Amy1 基因的转录水平是与其穗发芽抗性高度相关。 我国青藏高原青稞,尤其是农家品种的穗发芽抗性具有丰富的变异,蕴藏着穗发芽抗性育种的宝贵资源。本研究为青稞穗发芽抗性育种建立了合理抗性评价体系,筛选出可供育种使用的特殊材料,阐明了农艺性状可辅助穗发芽抗性育种,同时还对穗发芽抗性与α-淀粉酶基因的结构和表达关系进行分析,为青稞穗发芽抗性资源筛选奠定了基础。 Preharvest sprouting (PHS) is a serious problem in crop production. It often takes place when encountering damp, cold conditions at harvest time and results in the decrease of grain quality and great loss of yield by triggering the synthesis of endosperm degrading enzymes (mostly the α-amylase). Therefore, PHS is regarded as an important criterion for crop breeding. In order to minimize the risk of PHS, resistant genotypes are highly required. Hulless barley (Hordeum vulgare ssp. vulgare) is the staple food crop in Qinghai-Tibetan Plateau from of old, where is one of the origin and genetic diversity centers of hulless barley. Recently, interest in hulless barley has been sparked throughout the world due to the demonstrations of its great potential in health food industry and fuel alcohol production. Indeed, hulless barley can also be utilized to produce good quality malt if the appropriate malting conditions are used. In China, overcast and rainy conditions often occur at maturity of hulless barley and cause an adverse on its production and application. PHS resistant genotypes, therefore, are highly required for the hulless barley breeding programs. However, few investigations have been made so far on this issue. The objectives of this study were: 1) to assessment of methods used in testing preharvest sprouting resistance in hulless barley; 2) to evaluate the variability and characteristics of PHS resistance of hulless barley from Qinghai-Tibet Plateau in China; 3) to select potential parents for PHS resistance breeding; 4) to primarily study on the molecular mechanism of PHS resistance of hulless barley. Our results are as followed: 1. We investigated the temperature effects on seed germination and seed dormancy expression of hulless barley, discussed appropriate temperature range for screening of PHS resistant varieties, and analyzed the mechanism of seed dormancy expression of hulless barley. The dormancy level of 13 hulless barley were evaluated by GI (germination index) values calculating by seed germination tests at temperature of 10,15,20,25,30℃ in darkness. There were great differences in temperature sensitivity among these accessions. The insensitive accessions showed low dormancy at any temperature while the dormancy expression of sensitive accessions could be restrained by low temperature and induced by high temperature. The temperature range of 15℃ to 25℃ was workable for estimating of dormancy level of hulless barley according to our data. Analysis of α-amylase activity showed that the temperature effects on seed germination and the expression of seed dormancy be achieved probable via regulating of α-amylase activity. Furthermore, we evaluated the differences in sprouting index (SI), sprouting rate (SR), germination index (GI) and α-amylase activity (AA) between Maerkang and Chengdu among 34 accessions of hulless barley from Qinghai-Tibetan Plateau in China. These PHS sprouting parameters were significantly affected by accession×location, and they had correlation between each other. GI was the most reliable parameter because of its low CV value, good repeatability and simple operation. SI could assist in differentiating between accessions of similar dormancy or overall evaluation of the resistance. AA was bad in repeatability and had relatively complex testing method, therefore, not appropriate for breeding and evaluation and screening of PHS resistant materials. Besides, since PHS resistance of hulless barley was greatly influenced by its growth environment, possibly much influencing factors and variations between cultivated conditions should be considered. 2. In this study, large variation was found among 113 genotypes of hulless barley (Hordeum vulgare ssp.vulgare) from Qinghai-Tibetan Plateau in China, based on the sprouting index (SI), germination index (GI) and α-amylase activity (AA) which derived from sprouting test of intact spikes, germination test of threshed seeds and determination of α-amylase activity, respectively. The range of SI, GI and AA was 1.00~8.86, 0.01~0.97 and 0.00~2.76,the mean was 4.72, 0.63 and 1.22 espectively. Six resistant genotypes, including ‘XQ9-5’, ‘XQ33-9’, ‘XQ37-5’, ‘XQ42-9’, ‘XQ45-7’ and ‘JCL’, were identified based on SI. Integrating the three parameters, it was clear that both hulls and seeds involved in PHS resistance in intact spikes of hulless barley and there was no long-existent embryo dormancy found among the test genotypes. All the genotypes, except ‘XQ45-7’, had detectable α-amylase activity on the 4th day after germination. There was PHS resistance imposed by the hull and seed per se and the two factors can act together or independent of each other. Besides, landraces or Tibet hulless barley had a wider variation and relatively more PHS resistance when compared with cultivars or Sichuan hulless barley. No significant difference was found among hulless barley of different seed colors. The correlation analysis showed PHS resistance was negatively related to hundred grain weight, days to flowering, days to maturity, spike length, awn length and flag length but not related to plant height. This study provides essential information and several donor parents for breeding of resistance to PHS. 3. Alpha-amylase isozymes are encoded by a family of multigenes. They highly express in germinating seeds and is closely related to seed germination ability. In barley germinating seeds, the activity of high pI α-amylase is much higher than low pI α-amylase. The aim of this study was to determine the relationship between preharvest sprouting resistance of hulless barley and the gene structure of Amy1 gene which encodes high pI α-amylase. The coding region and cDNA of Amy1 gene of three resistant accessions, including ‘XQ32-5’ (TR1), ‘XQ37-5’ (TR2), ‘XQ45-7’ (TR3), two susceptible accessions ‘97-15’ (TS1), ‘9657’ (TS2) and one highly dormant barley accession ‘SAMSON’ (SAM) was cloned. Analysis of their DNA sequences revealed there were three exons and two introns in Amy1 gene. Thirteen variable sites were in exon2 and exon3, 2 variable sites were in intron2. SAM and TS1 had a GAACT insert segment in the same site in intron2. Only 8 variable sites caused the change of amino acid residues. There were 99% of similarity between the tested hulless barley and some of the variable sites might be related with preharvest sprouting resistance. Then, we investigated the expression level of Amy1 gene in the 7-day germination test. Results of quantitative real-time PCR indicated that the relative expression trends of Amy1 gene were the same but had significant differences in the increase fashion between hulless barleys and no detectable expression was found in SAM. Susceptible accessions had earlier expression and faster increase and reached the maximum on day 4 ~ day 5. Besides, total transcripts level was found lower in resistant accessions than susceptible accessions. This study indicated that α-amylase activity was highly related to the transcription level of Amy1 gene which not correlated to missense mutation sites. In conclusion, hulless barley, especially the landraces from Qinghai-Tibetan Plateau in China possesses high degree of variation in PHS performance, which indicates the potential of Tibetan hulless barley as a good source for breeding of resistance to PHS. This study provides several donor parents for breeding of resistance to PHS. Our results also demonstrate that agronomic traits may be used as assistants for PHS resistance selection in hulless barley. Besides, analysis of high pI α-amylase coding gene Amy1 revealed the relative high expression of was Amy1 one of the mainly reason of different PHS resistance level in hulless barley.

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Tank cultivation of marine macroalgae involves air-agitation of the algal biomass and intermittent light conditions, i.e. periodic, short light exposure of the thalli in the range of 10 s at the water surface followed by plunging to low light or darkness at the tank bottom and recirculation back to the surface in the range of 1-2 min. Open questions relate to effects of surface irradiance on growth rate and yield in such tumble cultures and the possibility of chronic photoinhibition in full sunlight. A specially constructed shallow-depth tank combined with a dark tank allowed fast circulation times of approximately 5 s, at a density of 4.2 kg fresh weight (FW) m(-2) s(-1). Growth rate and yield of the red alga Palmaria palmata increased over a wide range of irradiances, with no signs of chronic photoinhibition, up to a growth-saturating irradiance of approximately 1600 mumol m(-2) s(-1) in yellowish light supplied by a sodium high pressure lamp at 16 h light per day. Maximum growth rate ranged at 12% FW d(-1), and maximum yield at 609 g FW m(-2) d(-1). This shows that high growth rates of individual thalli may be reached in a dense tumble culture, if high surface irradiances and short circulation times are supplied. Another aspect of intermittent light relates to possible changes of basic growth kinetics, as compared to continuous light. For this purpose on-line measurements of growth rate were performed with a daily light reduction by 50% in light-dark cycles of 1, 2 or 3 min duration during the daily light period. Growth rates at 10degreesC and 50 mumol photon m(-2) s- 1 dropped in all three intermittent light regimes during both the main light and dark periods and reached with all three periodicities approximately 50% of the control, with no apparent changes in basic growth kinetics, as compared to continuous light.

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Dissertação apresentada à Universidade Fernando Pessoa como parte dos requisitos para a obtenção do grau de Mestre em Psicologia, ramo de Psicologia Clínica e da Saúde

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Anaerobic digestion (AD) of biodegradable waste is an environmentally and economically sustainable solution which incorporates waste treatment and energy recovery. The organic fraction of municipal solid waste (OFMSW), which comprises mostly of food waste, is highly degradable under anaerobic conditions. Biogas produced from OFMSW, when upgraded to biomethane, is recognised as one of the most sustainable renewable biofuels and can also be one of the cheapest sources of biomethane if a gate fee is associated with the substrate. OFMSW is a complex and heterogeneous material which may have widely different characteristics depending on the source of origin and collection system used. The research presented in this thesis investigates the potential energy resource from a wide range of organic waste streams through field and laboratory research on real world samples. OFMSW samples collected from a range of sources generated methane yields ranging from 75 to 160 m3 per tonne. Higher methane yields are associated with source segregated food waste from commercial catering premises as opposed to domestic sources. The inclusion of garden waste reduces the specific methane yield from household organic waste. In continuous AD trials it was found that a conventional continuously stirred tank reactor (CSTR) gave the highest specific methane yields at a moderate organic loading rate of 2 kg volatile solids (VS) m-3 digester day-1 and a hydraulic retention time of 30 days. The average specific methane yield obtained at this loading rate in continuous digestion was 560 ± 29 L CH4 kg-1 VS which exceeded the biomethane potential test result by 5%. The low carbon to nitrogen ratio (C: N <14:1) associated with canteen food waste lead to increasing concentrations of volatile fatty acids in line with high concentrations of ammonia nitrogen at higher organic loading rates. At an organic loading rate of 4 kg VS m-3day-1 the specific methane yield dropped considerably (381 L CH4 kg-1 VS), the pH rose to 8.1 and free ammonia (NH3 ) concentrations reached toxicity levels towards the end of the trial (ca. 950 mg L-1). A novel two phase AD reactor configuration consisting of a series of sequentially fed leach bed reactors connected to an upflow anaerobic sludge blanket (UASB) demonstrated a high rate of organic matter decay but resulted in lower specific methane yields (384 L CH4 kg-1 VS) than the conventional CSTR system.

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Magnetic compass orientation in a night-migratory songbird requires that Cluster N, a cluster of forebrain regions, is functional. Cluster N, which receives input from the eyes via the thalamofugal pathway, shows high neuronal activity in night-migrants performing magnetic compass-guided behaviour at night, whereas no activation is observed during the day, and covering up the birds' eyes strongly reduces neuronal activation. These findings suggest that Cluster N processes light-dependent magnetic compass information in night-migrating songbirds. The aim of this study was to test if Cluster N is active during daytime migration. We used behavioural molecular mapping based on ZENK activation to investigate if Cluster N is active in the meadow pipit (Anthus pratensis), a day- and night-migratory species. We found that Cluster N of meadow pipits shows high neuronal activity under dim-light at night, but not under full room-light conditions during the day. These data suggest that, in day- and night-migratory meadow pipits, the light-dependent magnetic compass, which requires an active Cluster N, may only be used during night-time, whereas another magnetosensory mechanism and/or other reference system(s), like the sun or polarized light, may be used as primary orientation cues during the day.