972 resultados para culture conflict


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Polyculture of seaweeds alongside fed animal aquaculture is an environmentally friendly means of avoiding eutrophication problem both in land-based and sea-based monoculture systems. Many aspects of such polyculture systems have been described, but little attention has been given to the impact of live seaweeds on the microbiological properties of the water that connects the algae and animals. In this investigation, the Pacific red alga Gracilaria textorii was cultured in a recirculated dual tank system (150 L) with the juvenile abalone Haliotis discus hannai. Dynamic changes of total bacteria (TB) and total Vibrio (TV) in the water of polyculture and monoculture systems were evaluated. Results revealed that (1) level of TB in the polyculture was constantly higher than in the monoculture over a 6.5-day period. While levels of TV in the polyculture was detected to be constantly lower than in the monoculture, (2) integration of G. textorii in the abalone culture changed the Vibrio compositions in the water as judged by the changes of bacteria colony types; (3) application of artificial diet led to dramatic increase of the levels in TB and TV in both systems at 12 h after application in the 24-h test and resulted in selective propagation of Vibrio in the water in the monoculture system; (4) polyculture of G. textorii with juvenile abalone in combination with feeding with live algal diet helped to maintain low levels of TV and the balance of the Vibrio composition; (5) living biomass of G. textorii was effective in preventing propagation of two purified Vibrio strains (V alginolaticus and V logei) in the water. These results provide a general basis of the dynamic changes of levels in TB and TV in a seaweed-abalone polyculture system with or without artificial diet in tanks. (c) 2005 Elsevier B.V All rights reserved.

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In the current abalone hatchery in China, insufficient diatoms on vertically placed corrugated pvc plates at later stage often could not support the growth of postlarvae up to the stage that they can feed on live macroalgae. As a result, stripping the spats (35 mm) off by anaesthetization and switching the diet from live diatoms to artificial powdered diet in combination has to be performed in most of the abalone farms. This manipulation normally leads to more than 50% mortality. Here we report the direct use of the unicellular green alga Platymonas helgolandica Kylin var. tsingtaoensis as a potential alga to be used to settle the veliger larvae of the Pacific abalone Haliotis discus hannai and to feed the postlarvae. Settlement rate of 2-day-old veliger larvae in mono culture of P helgolandica could be as high as 92% ( +/- 4.2%) on day 10 in small scale trials, higher than that in the selected benthic diatom strain (53.6% +/- 12.7%) when settled in the water in which bacteria propagation was controlled by treatment of 2 ppm of benzylpenicillinum calcium and streptomycin sulfate. Postlarvae fed solely on P. helgolandica or the selected benthic diatom Navicula-2005-A grew at rates of 40.1 ( +/- 1.9) and 45.8 (+/- 13.4) mu m day(-1), respectively, when raised at 22 degrees C until day 50 postfertilization. P. helgolandica was shown to have distinct diurnal settling rhythm characterized with a peak of settled cells in the middle of the night for cell division and a peak of free-swimming cells in the middle of the day. High density of attached P. helgolandica cells on the inner surface of the culture facility in the night fits the nocturnal feeding behavior of the abalone spats. Judged by the promising larvae settling rate, growth and survival rates of the postlarvae fed with this alga, the free-swimming micro-green alga P. helgolandica constitutes a potential species for settling the veliger larvae and for supporting the growth of postlarvae as well. (c) 2006 Published by Elsevier B.V.

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We examined the growth, survival and immune response of the scallop, Chlamys farreri, during a 1-year period in deep water of Haizhou Bay. Scallops were cultured using two methods: (1) in lantern nets at a 5 m depth and (2) in a bottom culture system (sleeves) on the seabed at about a 25 m depth. Shell heights, meat dry weight and immune activities in the haemolymph (superoxide dismutase and myeloperoxidase) were measured bimonthly or quarterly from July 2007 to June 2008. Survival was measured at the end of the study and environmental parameters in the experimental layers were monitored during the experiment. The growth and immune activities of scallops were lower when the water temperature was high, which was consistent with the main mortality occurring in summer. The growth and immunity of scallops were higher in the suspended culture than in the bottom culture during the experiment, with the exception of shell growth during the last study period. Survival of scallops in the suspended culture (54.6 +/- 12.3%) was significantly lower than that in the bottom culture (86.8 +/- 3.5%) at the end of this study. We conclude from our results that the high mortality of C. farreri can be prevented by culturing them in a bottom culture system before November of the first year, and then transferring them to a suspended culture to improve scallop production.

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In recent years, bivalve feces and powdered algae have been used as the food sources of holothurians in China. In this study, growth and energy budget for sea cucumber Apostichopus japonicus (Selenka) with initial wet body,veights of 32.5 1.0 g (mean +/- SE, n=45) when fed with five different granule diets containing dried bivalve feces and/or powdered algae in water temperature 13.2-19.8 degrees C and salinity 30-32ppt were quantified in order to investigate how diets influence growth and energy distribution and to find out the proper diet for land-based intensive culture of this species. Results showed that diets affected the food ingestion, feces production, food conversion efficiency and apparent digestive ratios, hence the growth and energy budget. Sea cucumbers fed with dried feces of bivalve showed poorer energy absorption, assimilation and growth than individuals fed with other four diets; this could be because feces-drying process removed much of the benefits. Dried bivalve feces alone, therefore, were not a suitable diet for sea cucumbers in intensive cultivation. The mixed diets of feces and powered algae showed promising results for cultivation of sub-adult Apostichopus japonicus, while animals fed with powdered algae alone, could not obtain the best growth. According to SGR of tested animals, a formula of 75% feces and 25% powdered algae is the best diet for culture of this species. Extruded diets were used in the present experiment to overcome shortcomings of the traditional powdered feeds, however, it seems a conflict exists between drying bivalve feces to form extruded diets and feeding sea cucumbers with fresh feces which contain beneficial bacteria. Compared with other echinoderms, in holothurians the energy deposited in growth is lower and the energy loss in feces accounts for the majority of the ingested energy. Such detailed information could be helpful in further development of more appropriate diets for culture of holothurians. (c) 2006 Elsevier B.V. All rights reserved.

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Fed fish farms produce large amounts of wastes, including dissolved inorganic nitrogen and phosphorus. In China, fish mariculture in coastal waters has been increasing since the last decade. However, there is no macroalgae commercially cultivated in north China in warm seasons. To exploit fish-farm nutrients as a resource input, and at the same time to reduce the risk of eutrophication, the high-temperature adapted red alga Gracilaria lemaneiformis (Bory) Dawson from south China was co-cultured with the fish Sebastodes fuscescens in north China in warm seasons. Growth and nutrient removal from fish culture water were investigated in laboratory conditions in order to evaluate the nutrient bioremediation capability of G. lemaneiformis. Feasibility of integrating the seaweed cultivation with the fed fish-cage aquaculture in coastal waters of north China was also investigated in field conditions. Laboratory seaweed/fish co-culture experiments showed that the seaweed was an efficient nutrient pump and could remove most nutrients from the system. Field cultivation trials showed that G. lemaneiformis grew very well in fish farming areas, at maximum growth rate of 11.03% day(-1). Mean C, N, and P contents in dry thalli cultured in Jiaozhou Bay were 28.9 +/- 1.1%, 4.17 +/- 0.11 % and 0.33 +/- 0.01 %, respectively. Mean N and P uptake rates of the thalli were estimated at 10.64 and 0.38 mu mol g(-1) dry weight h(-1), respectively. An extrapolation of the results showed that a 1-ha cultivation of the seaweed in coastal fish fanning waters would give an annual harvest of more than 70 t of fresh G. lemaneiformis, or 9 t dry materials; 2.5 t C would be produced, and simultaneously 0.22 t N and 0.03t P would be sequestered from the seawater by the seaweed. Results indicated that the seaweed is suitable as a good candidate for seaweed/fish integrated mariculture for bioremediation and economic diversification. The integration can benefit economy and environment in a sustainable manner in warm seasons in coastal waters of north China. (c) 2005 Elsevier B.V. All rights reserved.

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Magnetotactic bacteria (MTB) are ubiquitous in aquatic habitats. Because of their fastidious requirements for growth conditions, only very few axenic MTB cultures have been obtained worldwide. In this study, we report a novel marine magnetotactic spirillum axenic culture, designated as QH-2, isolated from the China Sea. It was able to grow in semi-solid or liquid chemically defined medium. The cells were amphitrichously flagellated and contained one single magnetosome chain with an average number of 16 magnetosomes per cell. Phosphate and lipid granules were also observed in the cells. Both rock magnetism and energy-dispersive X-ray spectroscopy characterizations indicated that the magnetosomes in QH-2 were single-domain magnetites (Fe3O4). QH-2 cells swam mostly in a straight line at a velocity of 20-50 mu m/s and occasionally changed to a helical motion. Unlike other magnetotactic spirilla. QH-2 cells responded to light illumination. As a consequence of illumination, the cells changed the direction in which they swam from parallel to the magnetic field to antiparallel. This response appears to be similar to the effect of an increase in [O-2]. Analysis of the QH-2 16S rRNA sequence showed that it had greater than 11% sequence divergence from freshwater magnetotactic spirilla. Thus, the marine QH-2 strain seems to be both phylogenetically and magnetotactically distinct from the freshwater Magnetospirillum spp. studied previously. (C) 2010 Elsevier Masson SAS. All rights reserved.

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Studies on reproduction, hatchery management, and culture of Manila clams Ruditapes philippinarum were carried out in an attempt to optimize their culture conditions and techniques. Results from these studies led to the development of a three-phase culture method for Manila clam farming in northern China. The key components of the new method were: 1) early spawning and over-wintering indoors (greenhouse); 2) optimized larval culture conditions and techniques; 3) juvenile rearing in shallow, fertilized nursery ponds; 4) optimized stocking size and density and substrate for mudflat grow out. Broodstock were maturated indoors for a month from early April to early May. Primarily because of higher water temperatures in the greenhouse the clams spawned more than one month earlier than in the natural environment. From May to July, juveniles were reared for 1-2 months indoors to a size of 2.0-3.0 mm in shell length before being moved to outdoor, pre-disinfected, nursery ponds. Juveniles were then reared in the nursery ponds for one month to about 1.0 cm before being transferred to the mudflat for grow out. Juvenile clams in nursery ponds grew considerably faster than in the natural environment probably because of higher temperatures and more abundant natural food. During grow out, the clams were reared for 4-7 months until they reached a market size (3.0-3.3 cm). Juveniles produced after August were over-wintered in the greenhouse in which the water temperature was about 3 degrees C higher than that of the outdoor environment. Juveniles grew at an average rate of > 20 mu m day(-1), while in the natural environment no growth was observed during winter because of low temperatures. Juveniles in the greenhouse grew to 2-3 mm by the following March before being moved into outdoor nursery ponds. The three-phase culture method not only shortened the production period from spawn to market size from 24-36 months to about 10-14 months, but also prolonged the spawning season from 2 to 7 months, resulting in increased production of seed and market-size clams. Compared with the traditional method, the new method could increase the yield of market-size clams by 10-11 times, and increase the profit per ha mudflat by as much as 124 times and the profit per kg market-size clams produced by 13 times. (c) 2006 Elsevier B.V. All rights reserved.

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Repeated-batch cultures of strawberry cells (Fragaria ananassa cv. Shikinari) subjected to four medium-shift procedures (constant LS medium, constant B5 medium, alternation between LS and B5 starting from LS and alternation between LS and B5 starting from B5) were investigated for the enhanced anthocyanin productivity. To determine the optimum period for repeated batch cultures, two medium-shift periods of 9 and 14 days were studied, which represent the end of the exponential growth phase and the stationary phase. By comparison with the corresponding batch cultures, higher anthocyanin productivity was achieved for all the repeated-batch cultures at a 9-day medium-shift period. The average anthocyanin productivity was enhanced 1.7-and 1.76-fold by repeated-batch cultures in constant LS and constant B5 medium at a 9-day shift period for 45 days, respectively. No further improvement was observed when the medium was alternated between LS (the growth medium) and B5 (the production medium). Anthocyanin production was unstable at a 14-day shift period regardless of the medium-shift procedures. The results show that it is feasible to improve anthocyanin production by a repeated-batch culture of strawberry cells.

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Emotional support, as an important form of social supports, has great impact on the life of both caregivers and receivers. Many studies on adult children and old parents indicate that emotional support is closely related to parents’ well-being, and the relation quality between old parents and adult children is one of the factors influencing adult children’s support offering. However, the study on adolescents’ emotional support to their parents is quite rare. What’s more, it has been found that emotional support skills children have learnt at home have life-time influence on children’s response to other’s emotional needs. It is assumed that to some extent the emotional support styles between parents and adolescents are relatively stable, and they are related to the care children give to their parents after they advance to old age. Hence, it is necessary to study the emotional support of adolescent in order to at last improve the well-being of old parents. Totally speaking, the aim of this study is to explore the relation between parenting styles and adolescents’ emotional support offering, as well as the effects of mother-child relationships. In addition, culture is a factor having impact on parenting styles, parent-child relationships and emotional support. So we have designed this cross-cultural study to explore cultural differences. The results are as follows: (1) As to Chinese and Indonesian mothers, their Acceptance of adolescents’ behaviors has significant positive predictive effect on children’s emotional support. Besides, the Intimacy and Approval dimensions of mother-child relationships partially mediate the path from parenting styles to emotional support offering, and those effects have no significant difference in China and Indonesia. (2) Chinese and Indonesian mother’s Rejection to adolescents has significant positive predictive effect on Conflict between mothers and adolescents, but has no direct effect on adolescents’ emotional support offering. (3) Adolescents’ support offering has no significant predictive effect on their willingness to help their parents. (4) Adolescents’ support offering has significant predictive effect on their motivation to provide emotional support to their parents. However, the relation between adolescents’ support offering and the willingness to help their parents is not clear. (5) Adolescents have scored high in Acceptance parenting style dimension and relatively low in Rejection dimension, which indicate that mothers in China and Indonesia adopt positive parenting styles. Both Chinese and Indonesian mother-child relationships are good. However, Indonesian adolescents have perceived more Intimacy and Approval from mothers, and there is no significant difference between Chinese and Indonesian adolescents and mothers in the dimension of Conflict.

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The relationship between the management and the culture was explored from the view of social norm's theory. In concrete terms, the differences of the hierarchical structure of the social norm among the Chinese, the Japanese and the American were studied systematically by using interview, case study, questionnaire survey and the structure equation model, etc. The results were: (1) The basic two types of the social norms of the Chinese, the American and the Japanese were the same: the external control norm and the internal control norm. The basic dimensions of the two types of norms composed of moral principle, value orientation, the law and the rules, and the social custom were consistent among the three countries. Furthermore, the dimensions of social norms were hierarchical because of the functioning of the different culture, which consisted of the hierarchical structure system. (2) Although there were the same dimensions among the three countries, the contents of these dimensions had both the common norms surpassing the specific culture and the particular norms depending on the specific culture. (3) The basic structures of the social norms in China and in Japan were the same: the internal control norms played a main role and the external control norm was auxiliary. On one hand, within the internal norm of the Chinese, the moral principle was the main force while the value orientation was the supplementary; within the external norm, the law and the rules was the main force while the social culture custom was supplementary. On the other hand, the relationship between the external and the internal dimensions of the Japanese turned out to be contrary to those of the Chinese. (4) The structure of the American social norms were different from the Chinese: for the American, the external control norm played a main role while the internal control norm was assistant. Furthermore, the law and the rule was the major aspect while the social costumes was the second in the external control dimension. In addition, the value orientation led the performance style of the American, while the moral principle played the second role in the internal control structure. (5) The social norms related to the management performance were found including work responsibility, organization commitment, meeting making-decision, communication style, work duty and interpersonal conflict by inventory and case study. The mangers from China, Japan and America had significant different views on paying attention to the management norms. In a word, the culture differences of the social norm were the fundamental reason of the management conflict.

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Marine sponge cell culture is a potential route for the sustainable production of sponge-derived bioproducts. Development of a basal culture medium is a prerequisite for the attachment, spreading, and growth of sponge cells in vitro. With the limited knowledge available on nutrient requirements for sponge cells, a series of statistical experimental designs has been employed to screen and optimize the critical nutrient components including inorganic salts (ferric ion, zinc ion, silicate, and NaCl), amino acids (glycine, glutamine, and aspartic acid), sugars (glucose, sorbitol, and sodium pyruvate), vitamin C, and mammalian cell medium (DMEM and RPMI 1640) using MTT assay in 96-well plates. The marine sponge Hymeniacidon perleve was used as a model system. Plackett-Burman design was used for the initial screening, which identified the significant factors of ferric ion, NaCl, and vitamin C. These three factors were selected for further optimization by Uniform Design and Response Surface Methodology (RSM), respectively. A basal medium was finally established, which supported an over 100% increase in viability of sponge cells.

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Purpose and rationale The purpose of the exploratory research is to provide a deeper understanding of how the work environment enhances or constrains organisational creativity (creativity and innovation) within the context of the advertising sector. The argument for the proposed research is that the contemporary literature is dominated by quantitative research instruments to measure the climate and work environment across many different sectors. The most influential theory within the extant literature is the componential theory of organisational creativity and innovation and is used as an analytical guide (Amabile, 1997; Figure 8) to conduct an ethnographic study within a creative advertising agency based in Scotland. The theory suggests that creative people (skills, expertise and task motivation) are influenced by the work environment in which they operate. This includes challenging work (+), work group supports (+), supervisory encouragement (+), freedom (+), sufficient resources (+), workload pressures (+ or -), organisational encouragement (+) and organisational impediments (-) which is argued enhances (+) or constrains (-) both creativity and innovation. An interpretive research design is conducted to confirm, challenge or extend the componential theory of organisational creativity and innovation (Amabile, 1997; Figure 8) and contribute to knowledge as well as practice. Design/methodology/approach The scholarly activity conducted within the context of the creative industries and advertising sector is in its infancy and research from the alternative paradigm using qualitative methods is limited which may provide new guidelines for this industry sector. As such, an ethnographic case study research design is a suitable methodology to provide a deeper understanding of the subject area and is consistent with a constructivist ontology and an interpretive epistemology. This ontological position is conducive to the researcher’s axiology and values in that meaning is not discovered as an objective truth but socially constructed from multiple realties from social actors. As such, ethnography is the study of people in naturally occurring settings and the creative advertising agency involved in the research is an appropriate purposive sample within an industry that is renowned for its creativity and innovation. Qualitative methods such as participant observation (field notes, meetings, rituals, social events and tracking a client brief), material artefacts (documents, websites, annual reports, emails, scrapbooks and photographic evidence) and focused interviews (informal and formal conversations, six taped and transcribed interviews and use of Survey Monkey) are used to provide a written account of the agency’s work environment. The analytical process of interpreting the ethnographic text is supported by thematic analysis (selective, axial and open coding) through the use of manual analysis and NVivo9 software Findings The findings highlight a complex interaction between the people within the agency and the enhancers and constraints of the work environment in which they operate. This involves the creative work environment (Amabile, 1997; Figure 8) as well as the physical work environment (Cain, 2012; Dul and Ceylan, 2011; Dul et al. 2011) and that of social control and power (Foucault, 1977; Gahan et al. 2007; Knights and Willmott, 2007). As such, the overarching themes to emerge from the data on how the work environment enhances or constrains organisational creativity include creative people (skills, expertise and task motivation), creative process (creative work environment and physical work environment) and creative power (working hours, value of creativity, self-fulfilment and surveillance). Therefore, the findings confirm that creative people interact and are influenced by aspects of the creative work environment outlined by Amabile (1997; Figure 8). However, the results also challenge and extend the theory to include that of the physical work environment and creative power. Originality/value/implications Methodologically, there is no other interpretive research that uses an ethnographic case study approach within the context of the advertising sector to explore and provide a deeper understanding of the subject area. As such, the contribution to knowledge in the form of a new interpretive framework (Figure 16) challenges and extends the existing body of knowledge (Amabile, 1997; Figure 8). Moreover, the contribution to practice includes a flexible set of industry guidelines (Appendix 13) that may be transferrable to other organisational settings.