Effect of temperature, food availability, and estradiol injection on gametogenesis and gender in the pearl oyster Pinctada margaritifera

The black-lip pearl oyster Pinctada margaritifera is a protandrous hermaphrodite species. Its economic value has led to the development of controlled hatchery reproduction techniques, although many aspects remain to be optimized. In order to understand reproductive mechanisms and their controlling factors, two independent experiments were designed to test hypotheses of gametogenesis and sex ratio control by environmental and hormonal factors. In one, pearl oysters were exposed under controlled conditions at different combinations of temperature (24 and 28°C) and food level (10,000 and 40,000 cells mL−1); whereas in the other, pearl oysters were conditioned under natural conditions into the lagoon and subjected to successive 17β-estradiol injections (100 μg per injection). Gametogenesis and sex ratio were assessed by histology for each treatment. In parallel, mRNA expressions of nine marker genes of the sexual pathway (pmarg-foxl2, pmarg-c43476, pmarg-c45042, pmarg-c19309, pmarg-c54338, pmarg-vit6, pmarg-zglp1, pmarg-dmrt, and pmarg-fem1-like) were investigated. Maximum maturation was observed in the treatment combining the highest temperature (28°C) and the highest microalgae concentration (40,000 cells mL−1), where the female sex tended to be maintained. Injection of 17β-estradiol induced a significant increase of undetermined stage proportion 2 weeks after the final injection. These results suggest that gametogenesis and gender in adult pearl oysters can be controlled by environmental factors and estrogens. While there were no significant effects on relative gene expression, the 3-gene-pair expression ratio model of the sexual pathway of P. margaritifera, suggest a probable dominance of genetic sex determinism without excluding a mixed sex determination mode (genetic + environmental)

Influence of food restriction on the reproduction and larval performance of matrinxã, Brycon amazonicus (Spix and Agassiz, 1829)

Este estudo avaliou o efeito da restrição alimentar e realimentação na reprodução de fêmeas e no crescimento inicial e sobrevivência de larvas de matrinxã, Brycon amazonicus. Matrizes distribuídas em 8 viveiros (15 peixes/tanque) foram alimentadas diariamente (em 4 tanques - G1) e alimentados em ciclos de 3 dias de alimentação seguidos de 2 dias de restrição (em 4 tanques - G2) por 6 meses antes da desova. Na indução à desova, 57% das fêmeas no G1 e 45% no G2 desovaram. Os pesos médios dos oócitos foram 208,1 g (G1) e 131,6 g (G2), sendo os oócitos G2 menores (1,017 ± 0,003 mm) que os oócitos de G1 (1,048 ± 0,002 mm). As taxas de fertilização (71,9 ± 12,6% e 61,2 ± 13,7%) e de eclosão (61,3 ± 33,9% e 67,5 ± 23,4%) entre os G1 e G2 não diferiram. Larvas foram coletadas na eclosão e às 24, 48 e 72 horas de incubação para medida do crescimento e as restantes transferidas para aquários e amostradas 1, 5, 9 e 15 dias depois. Na transferência, as larvas G1 e G2 tinham pesos similares (1,5 ± 0,15 e 1,46 ± 0,07 mg), mas o comprimento das larvas G2 era maior (6,2 ± 0,13 e 6,7 ± 0,14 mm). Ao 9° dia, quando é recomendada a transferência dos juvenis para tanques externos, os juvenis G2 tinham peso (13,6 ± 0,26 e 18,9 ± 0,07 mg) e comprimento (11,8 ± 0,09 e 14,5 ± 0,04 mm) maiores, mas no 15º dia os juvenis G1 eram maiores em peso (90,2 ± 1,19 e 68,6 ± 0,77 mg) e comprimento (18,8 ± 0,16 e 18,5 ± 0,04 mm). Aos 15 dias, a prole das fêmeas submetidas à restrição alimentar apresentou sobrevivência mais alta que a prole das fêmeas alimentadas diariamente (24,7 ± 2,07% e 19,2 ± 1,91%). A restrição alimentar imposta às fêmeas de matrinxã, apesar de reduzir o número de fêmeas que desovaram e a quantidade de oócitos extrusados, não afetou a fertilização e eclosão das larvas e melhorou a sobrevivência final das larvas.

Public service motivation in public and nonprofit service providers: The cases of Belarus and Poland

The work motivation construct is central to the theory and practice of many social science disciplines. Yet, due to the novelty of validated measures appropriate for a deep cross-national comparison, studies that contrast different administrative regimes remain scarce. This study represents an initial empirical effort to validate the Public Service Motivation (PSM) instrument proposed by Kim and colleagues (2013) in a previously unstudied context. The two former communist countries analyzed in this dissertation—Belarus and Poland—followed diametrically opposite development strategies: a fully decentralized administrative regime in Poland and a highly centralized regime in Belarus. The employees (n = 677) of public and nonprofit organizations in the border regions of Podlaskie Wojewodstwo (Poland) and Hrodna Voblasc (Belarus) are the subjects of study. ^ Confirmatory factor analysis revealed three dimensions of public service motivation in the two regions: compassion, self-sacrifice, and attraction to public service. The statistical models tested in this dissertation suggest that nonprofit sector employees exhibit higher levels of PSM than their public sector counterparts. Nonprofit sector employees also reveal a similar set of values and work attitudes across the countries. Thus, the study concludes that in terms of PSM, employees of nonprofit organizations constitute a homogenous group that exists atop the administrative regimes. ^ However, the findings propose significant differences between public sector agencies across the two countries. Contrary to expectations, data suggest that organization centralization in Poland is equal to—or for some items even higher than—that of Belarus. We can conclude that the absence of administrative decentralization of service provision in a country does not necessarily undermine decentralized practices within organizations. Further analysis reveals strong correlations between organization centralization and PSM for the Polish sample. Meanwhile, in Belarus, correlations between organization centralization items and PSM are weak and mostly insignificant. ^ The analysis indicates other factors beyond organization centralization that significantly impact PSM in both sectors. PSM of the employees in the studied region is highly correlated with their participation in religious practices, political parties, or labor unions as well as location of their organization in a capital and type of social service provided.^

The water-food nexus and the role of demand management

With the global population projected to reach 9 billion in 2050, demand for food is expected to increase by over 50% in 2030 and 70% in 2050 (UN-Water, 2013). Already agriculture is the largest user of water with irrigation accounting for nearly 70% of all freshwater withdrawals (UN-Water, 2016).

Trophic food web and ecosystem attributes of a water reservoir of the Ria Formosa (south Portugal)

Using a top-down modelling approach, a balanced trophic food web model of a water reservoir of the Ria Formosa lagoonal system was constructed. Few adjustments of input data were necessary to run the model since most of the parameters were estimated at the study site and the characteristics of the water reservoir allowed a high degree of control and precision in terms of sampling and data collection. Trophic levels of the 14 compartments included in the model varied between 1.0 for primary producers and detritus to 3.4 for carnivorous fish and the 14 groups were aggregated in a food chain with six trophic levels. The water reservoir has a detritus based food chain, with the majority of the biomass concentrated in the first two levels, the producers level and the herbivore/detritivore level (97.6%). The transfer efficiencies were low, and decreased with increasing level number, varying between 6.0 and 0.2%. The degree of "ecosystem maturity" was difficult to establish, but several parameters indicate that it could be high. The water reservoir studied, which has similar environmental and ecological characteristics as the Ria Formosa lagoon. is near its carrying capacity. (C) 2004, Elsevier B.V. All rights reserved.

Between service and loyalty: chancery and chancellors of Portugal in the 14th century

Estudo dos perfis e carreiras dos chancelares que serviram os reis portugueses ao longo do século XIV. Procura-se, com este estudo, reflectir sobre a evolução do papel dos eclesiásticos na construção da realeza e estabelecer tendências para a evolução dos perfis dos protagonistas do serviço régio.

Oral food perception and polyphenol-rich foods acceptance - the importance of knowing individuals saliva characteristics for promoting consumption

Polyphenols are widely present in fruits, vegetables, cereals and beverages. Their study gained scientific interest because of their beneficial effects on health. Although there is currently no official dietary recommendation for polyphenol intake, health professionals recommend the consumption of 5-8 daily portions of fruits and vegetables. This is not always achieved and, despite possible causes associated to practical schedule difficulties, the aversive bitter and astringent sensations associated to polyphenols may also lead to avoidance. As such, a better understanding on mechanisms responsible for differences among people, in polyphenol oral perception, is needed for promoting healthier choices. Saliva has been linked to polyphenol consumption. We have previously observed, in animal models, changes in salivary proteome induced by tannin-enriched diets. Moreover, differences in astringency perception were attributed to differences in salivary protein composition. In a recent experiment, we observed differences among individuals with dissimilar tannic-acid perception: people with high sensitivity for the oral sensations elicited by tannins have higher amounts of salivary cystatins and lower capacity to maintain their levels after tannic-acid ingestion. Additionally, and similarly to previous studies, salivary amylase was observed to be involved in tannin perception. In this presentation, oral cavity characteristics influencing the perception of polyphenol-containing foods will be discussed.

Effect of Food Restriction and Intense Physical Training on Estrous Cyclicity and Plasma Leptin Concentrations in Rats

Intense physical training and dietary energy restriction have been associated with consequences such as nutritional amenorrhea. We investigated the effects of intense physical training, food restriction or the combination of both strategies on estrous cyclicity in female rats, and the relationship between leptin ad these effects. Twenty-seven female Wistar rats were distributed into four groups: SF: sedentary, fed ad libitum; SR: sedentary subjected to 50% food restriction (based on the food intake of their fed counterparts); TF: trained (physical training on a motor treadmill with a gradual increase in speed and time), fed ad libitum; TR; trained with 50% food restriction. We analysed estrous cyclicity, plasma leptin and estradiol as well as chemical composition of the carcass, body weight variation. and weight of ovaries and perirenal adipose tissue. Data demonstrate that physical training alone was not responsible for significant modifications in either carcass chemical composition or reproductive function. Food restriction reduced leptin levels in all animals and interrupted the estrous cyclicity in some animals, but only the combination of food restriction and physical training was capable of interrupting the estrous cyclicity in all animals. Leptin was not directly related to estrous cyclicity. From our findings, it may be concluded that there is an additive or synergistic effect of energy intake restriction and energy expenditure by intense physical training on estrous cyclicity. Leptin appears to be one among others factors related to estrous cycle, but it probably acts indirectly.

Fluoride ingestion from food items and dentifrice in 2-6-year-old Brazilian children living in a fluoridated area using a semiquantitative food frequency questionnaire

Objectives: The aim of this study was to evaluate the fluoride intake of 2-6-year-old Brazilian children using a semiquantitative food frequency questionnaire (FFQ) which also estimated fluoride intake from dentifrice. Methods: The FFQ was previously validated through application to 78 2-6-year-old Brazilian children and then administered to 379 children residing in an optimally fluoridated community in Brazil (Bauru, State of Sao Paulo). The FFQ was applied to the parents and used to estimate the food intake of the children. The constituents of the diet were divided into solids, water and other beverages. The fluoride content of the diet items was analyzed with the fluoride electrode. The questionnaire also estimated fluoride intake from dentifrice. Results: The average (+/- SD) fluoride intake from solids, water, other beverages and dentifrice was 0.008 +/- 0.005; 0.011 +/- 0.004; 0.009 +/- 0.014 and 0.036 +/- 0.028 mg F/kg body weight/day, respectively, totalizing 0.064 +/- 0.035 mg F/kg body weight/day. The dentifrice and the diet contributed with 56.3% and 43.7% of the daily fluoride intake, respectively. Among the children evaluated, 31.2% are estimated to have risk to develop dental fluorosis (intake > 0.07 mg F/kg body weight/day). Conclusions: The dentifrice was the main source of fluoride intake by the children evaluated. However, the fluoride concentration in food items also significantly contributed to the daily ingestion by 2-6-year-old children. The questionnaire used seems to be a promising alternative to duplicate diet to estimate the fluoride intake at this age range and may have potential to be used in broad epidemiological surveys.

Dietary trends: Estimates from food supply and survey data

Objective: To illustrate methodological issues involved in estimating dietary trends in populations using data obtained from various sources in Australia in the 1980s and 1990s. Methods: Estimates of absolute and relative change in consumption of selected food items were calculated using national data published annually on the national food supply for 1982-83 to 1992-93 and responses to food frequency questions in two population based risk factor surveys in 1983 and 1994 in the Hunter Region of New South Wales, Australia. The validity of estimated food quantities obtained from these inexpensive sources at the beginning of the period was assessed by comparison with data from a national dietary survey conducted in 1983 using 24 h recall. Results: Trend estimates from the food supply data and risk factor survey data were in good agreement for increases in consumption of fresh fruit, vegetables and breakfast food and decreases in butter, margarine, sugar and alcohol. Estimates for trends in milk, eggs and bread consumption, however, were inconsistent. Conclusions: Both data sources can be used for monitoring progress towards national nutrition goals based on selected food items provided that some limitations are recognized. While data collection methods should be consistent over time they also need to allow for changes in the food supply (for example the introduction of new varieties such as low-fat dairy products). From time to time the trends derived from these inexpensive data sources should be compared with data derived from more detailed and quantitative estimates of dietary intake.

Relationship of high energy expenditure and variation in dietary intake with reporting accuracy on 7 day food records and diet histories in a group of healthy adult volunteers

Objectives: To assess the accuracy of reporting from both a diet history and food record and identify some of the characteristics of more accurate reporters in a group of healthy adult volunteers for an energy balance study. Design: Prospective measurements in free-living people. Setting: Wollongong, Australia. Subjects: Fifteen healthy volunteers (seven male, eight female; aged 22 -59 y; body mass index (BMI) 19 - 33 kg/m(2)) from the local community in the city of Wollongong, Australia. Interventions: Measurement of energy intake via diet history interview and 7 day food records, total energy expenditure by the doubly labelled water technique over 14 days, physical activity by questionnaire, and body fat by dual-energy X-ray absorptiometry. Results: Increased misreporting of energy intake was associated with increased energy expenditure (r = 0.90, P < 0.0001, diet history; r(s)=0.79, P=0.0005, food records) but was not associated with age, sex, BMI or body fat. Range in number of recorded dinner foods correlated positively with energy expenditure (r(s)=0.63, P=0.01) and degree of misreporting (r(s)=0.71, P=0.003, diet history; r(s)=0.63, P=0.01, food records). Variation in energy intake at dinner and over the whole day identified by the food records correlated positively with energy expenditure (r=0.58, P = 0.02) and misreporting on the diet history (r=0.62, P=0.01). Conclusions: Subjects who are highly active or who have variable dietary and exercise behaviour may be less accurate in reporting dietary intake. Our findings indicate that it may be necessary to screen for these characteristics in studies where accuracy of reporting at an individual level is critical. Sponsorship: The study was supported in part by Australian Research Council funds made available through the University of Wollongong.

A probabilistic analysis of Clostridium perfringens growth during food service operations

The purpose of this study was threefold: first, the study was designed to illustrate the use of data and information collected in food safety surveys in a quantitative risk assessment. In this case, the focus was on the food service industry; however, similar data from other parts of the food chain could be similarly incorporated. The second objective was to quantitatively describe and better understand the role that the food service industry plays in the safety of food. The third objective was to illustrate the additional decision-making information that is available when uncertainty and variability are incorporated into the modelling of systems. (C) 2002 Elsevier Science B.V. All rights reserved.

Phage types of Salmonella Enteritidis isolated from clinical and food samples, and from broiler carcasses in Southern Brazil

272 isolates of Salmonella Enteritidis (111 isolated from frozen broiler chicken carcasses, 126 from human food and other biological materials involved in food poisoning outbreaks and 35 from different poultry materials) were selected for phage typing. From these, 111 were phage typed, 57.65% being classified as phage type 4, 32.43% as phage type 4a, 3.60% as phage type 6a and 0.90% as phage type 7, whereas 5.40% samples were not phage typeable. The predominance of phage type 4 is in agreement with the results published worldwide, and reinforces the need for studies related to the epidemiological meaning of these findings.

Food Allergy and Anaphylaxis in Infants and Preschool-Age Children

Food allergy (FA) prevalence data in infants and preschool-age children are sparse, and proposed risk factors lack confirmation. In this study, 19 children’s day care centers (DCC) from 2 main Portuguese cities were selected after stratification and cluster analysis. An ISAAC’s (International Study of Asthma and Allergies in Childhood) derived health questionnaire was applied to a sample of children attending DCCs. Outcomes were FA parental report and anaphylaxis. Logistic regression was used to explore potential risk factors for reported FA. From the 2228 distributed questionnaires, 1217 were included in the analysis (54.6%). Children’s median age was 3.5 years, and 10.8% were described as ever having had FA. Current FA was reported in 5.7%. Three (0.2%) reports compatible with anaphylaxis were identified. Reported parental history of FA, personal history of atopic dermatitis, and preterm birth increased the odds for reported current FA. A high prevalence of parental-perceived FA in preschool-age children was identified. Risk factor identification may enhance better prevention.

FOOD CONCENTRATION AND TEMPERATURE EFFECTS ON LIFE CYCLE CHARACTERISTICS OF TROPICAL CLADOCERA (Daphnia gessneri Herbst, Diaphanosoma sarsi Richard, Moina reticulata (Daday)): I. DEVELOPMENT TIME

The effects of food concentration and temperature on embryonic and postem-bryonic duration of three tropical species, Daphnia gessneri(1.5mm), Diaphanosoma sarsi(1.2mm) and Moina reticulata(0.8mm), were investigated as part of life cycle studies which included growth, body size and reproduction. These are the very first experimental studies undertaken on these species. The long-term growth experiments were performed under controlled laboratory conditions at all combinations of temperature (22"C, 27"C and 32"C) and constant food concentration (0.03, 0.05, 0.10, 0.25, 0.50 and 1.00 mgC/L) of the unicellular green alga Scenedesmus acutus.Animals were examined twice daily throughout their life cycle from the neonate to third adult instar. In all three species, temperature exerted the most powerful influence on embryonic duration but there was also a smaller food effect. In D. gessneri,postembry-onic durations remained more or less the same at food levels 0.25 mgC/L but were influenced by temperature. At food concentrations of 0.1 mgC/L or lower, postembryonic durations became increasingly prolonged, particularly at high temperatures. This threshold concentration is affected by temperature: in D. gessneri,it was 0.1 mgC/L at 22oC and 27oC but higher at 32oC (between 0.25 and 0.50 mgC/L). At the same temperature of 27oC, the food threshold level varied between species: it was higher (0.25 mgC/L) for D. sarsiand lower (0.05 mgC/L) for M. reticulatacompared with D. gessneri(0.1 mgC/L). In both embryonic and postembryonic durations there is a body size effect as the absolute durations were longest in the largest species and shortest in the smallest species In all three species, prolongation of postembryonic duration at combinations of high temperature and lowered food levels was accompanied by increased number of juvenile instars.