Aspects of the developmental biology of an intertidal predatory gastropod, Nucella lapillus were investigated for a population located on a mussel dominated shore at ^^ihitsand Bay, Cornwall. A field sampling programme revealed that the centre of abundance of. small Nucella {<3.4mm) occurred at lower shore levels than that of a ll larger individuals and the egg capsules. Laboratory studies danonstrated that hatchlings are both negatively geotactic and phototactic, directing than upshore and into crevices. The relative profitabilities of four different sized mussels to four developmental stages of Nucella v/ere investigated using both ability to promote grov/th and energy gain per unit handling time (E/Tj^) as measures of prey value. The response curves were similar m that proportionately large and small prey were less profitable than medium sized prey with the optimal prey size increasing with predator size. However the most profitable size according to the E/T^^ model was larger than in the grovrtli rate model because large meals appeared to be less efficiently utilized. An ontogenetic- shift in prey size selection was danonstrated in laboratory and field, the results of which were more accurately predicted by the grcwth rate model of prey value. Predatory events in the field were investigated using borehole dimension as an index of predator size. The feeding and growth of Nucella were investigated at differing periods of tidal atiersion. Growth rates were substantially reduced at anersion periods of above 30%, but these could not be wholly attributable to reduced feeding rates. Field growth trials danonstrated that a matiore size could be reached in 19-21 months, that growth does not cease at maturity, and that jxiveniles grow throughout the year. A strong correlation existed between growth rate and environmental temperature. Growth rates in the field were about 75% those in the laboratory, suggesting few constraints on foraging in the field.

Problem: High wage countries depend on SME's to lower unemployment, to trigger economic growth and to utilize the 'knowledge waste' created by large investments in human capital. However, due to their limited access to capital markets SME's are seen as unfavourably dependent on their own generation of internal funds to grow. Among SME's, IT firms are seen as most representative for this struggle, since they have i) a bad reputation within the public and institutional sector due to the dot-com era, and ii) assets with low collateral value (e.g. immaterial assets, human capital, knowledge, prototypes and ideas that all have unknown, unsecure and hard to predict second-hand or future values). Despite these unfavorable characteristics, some IT firms are growing considerably fast. What can we learn from them?  Purpose: Describe the financial situation of IT SME's. Investigate how those IT firms that are fast growing have grown and financed their growth, and how they have managed the effects of growth. Method: Due to the nature of the purpose a mixed method research approach was adopted. The quantitative investigation aimed at describing their fi-nancial situation and took the form of a statistical analysis of the entire IT firm population, using data from the Swedish database 'Affärsdata'. The qualitative approach took the form of telephone interviews with a sample of fast growing IT firms, to get closer to the reasoning behind their growth and it’s financing. This research approach enabled cross referencing, strengthening some of the empirical evidence found. Conclusion: Evidence was found on IT firms growing with assets of less collateral value resulting in low amounts of long term debt. Indications were found on the traditional life cycle perspective regarding SME finance has to be changed to fit IT firms; after surviving the first years of internal funding and years of overdependence on short term debt, they reach a stage (e.g. in a financial crisis, facing international expansion, or substantial R&D costs) when financial assistance is needed. Indications were also found on IT firms operating in a highly unpredictable environment demanding advanced cash management routines that today are not prioritized in favor of growth. To handle this, and to reach financial assistance when needed (most likely by involving a risk capitalist in exchange for firm ownership), those firms showing stability (i.e. through low personnel turnover, high profitability or a large cash buffer) seem to have been more successful.

<p><strong>Problem: </strong>High wage countries depend on SME's to lower unemployment, to trigger economic growth and to utilize the 'knowledge waste' created by large investments in human capital. However, due to their limited access to capital markets SME's are seen as unfavourably dependent on their own generation of internal funds to grow. Among SME's, IT firms are seen as most representative for this struggle, since they have i) a bad reputation within the public and institutional sector due to the dot-com era, and ii) assets with low collateral value (e.g. immaterial assets, human capital, knowledge, prototypes and ideas that all have unknown, unsecure and hard to predict second-hand or future values). Despite these unfavorable characteristics, some IT firms are growing considerably fast. What can we learn from them?  <strong></strong></p><p><strong>Purpose:</strong><strong> </strong>Describe the financial situation of IT SME's. Investigate how those IT firms that are fast growing have grown and financed their growth, and how they have managed the effects of growth.<strong></strong></p><p><strong>Method: </strong>Due to the nature of the purpose a mixed method research approach was adopted. The quantitative investigation aimed at describing their fi-nancial situation and took the form of a statistical analysis of the entire IT firm population, using data from the Swedish database 'Affärsdata'. The qualitative approach took the form of telephone interviews with a sample of fast growing IT firms, to get closer to the reasoning behind their growth and it’s financing. This research approach enabled cross referencing, strengthening some of the empirical evidence found.<strong></strong></p><p><strong>Conclusion: </strong>Evidence was found on IT firms growing with assets of less collateral value resulting in low amounts of long term debt. Indications were found on the traditional life cycle perspective regarding SME finance has to be changed to fit IT firms; after surviving the first years of internal funding and years of overdependence on short term debt, they reach a stage (e.g. in a financial crisis, facing international expansion, or substantial R&D costs) when financial assistance is needed. Indications were also found on IT firms operating in a highly unpredictable environment demanding advanced cash management routines that today are not prioritized in favor of growth. To handle this, and to reach financial assistance when needed (most likely by involving a risk capitalist in exchange for firm ownership), those firms showing stability (i.e. through low personnel turnover, high profitability or a large cash buffer) seem to have been more successful.</p>

The trace metals and pesticides are commonly found in surface water receiving industrial and agricultural effluents. However, the potential negative effects of these compounds on aquatic ecosystems have not been deeply studied. Hence, the aim of this study is to assess the single and combined effects of aluminum (Al) and atrazine on the development and growth rate of duckweed, Lemna minor L. The single exposures were implemented with either Al or atrazine at the concentration of 5, 50 and 500 μg L-1 and a binary exposure was conducted with 50 μg L-1 of Al and 5 μg L-1 of atrazine for two weeks. The results revealed that both Al and atrazine at the concentration of 500 μg L-1 strongly inhibited the development and growth rate of the duckweed. On the contrary, the mixture of Al and atrazine showed antagonistic effects on the plant. To our knowledge, this is the first report on the combined effects of these two contaminants on the duckweed. Therefore, our results could be useful for environmental managers in setting up and adjusting the safe guideline values in Vietnam for Al and atrazine in natural waters in term of ecological health protection. / Kim loại nặng và thuốc trừ sâu thường được tìm thấy trong các nguồn nước mặt, nơi tiếp nhận nước thải công nghiệp và nông nghiệp. Tuy nhiên, những ảnh hưởng tiềm tàng mang tính tiêu cực của những hợp chất này đối với hệ sinh thái thủy vực chưa được nghiên cứu đầy đủ. Do đó, mục tiêu của nghiên cứu này nhằm đánh giá những ảnh hưởng riêng lẻ và kết hợp của nhôm (Al) và atrazine lên sự phát triển và tốc độ sinh trưởng của bèo tấm, Lemma minor L. Sự phơi nhiễm riêng lẻ với Al hoặc atrazine được thực hiện ở các nồng độ 5, 50 và 500 μg L-1, trong khi đó, quá trình phơi nhiễm kết hợp được tiến hành với Al tại nồng độ 50 μg L-1 và atrazine tại nồng độ 5 μg L-1 trong hai tuần. Kết quả cho thấy cả Al và atrazine ở nồng độ phơi nhiễm 500 μg L-1 kìm hãm mạnh mẽ sự phát triển và tốc độ sinh trưởng của bèo tấm. Ngược lại, sự kết hợp Al và atrazine dẫn kết tác động triệt tiêu trên bèo tấm. Theo sự hiểu biết của chúng tôi, đây là ghi nhận đầu tiên về những ảnh hưởng kết hợp của hai chất gây ô nhiễm này lên bèo tấm. Vì vậy, những kết quả này có thể hữu ích cho các nhà quản lý môi trường tại Việt Nam trong việc thiết lập và điều chỉnh các giá trị an toàn đối với Al và Atrazie trong môi trường nước tự nhiên về khía cạnh bảo vệ sức khỏe sinh thái.

Xenobiotics are of human and environmental concerns due to their potential toxicity. Octylphenol is one of the very common and daily used xenobiotics in door and out door activities of human beings. Toxicity of octylphenol to aquatic organisms, especially to zooplankton (e.g. Daphnia magna) was investigated but not fully understood. In this study we evaluated the chronic effects of octylphenol at the concentrations of 5, 50 and 500 μg L-1 on Daphnia magna over a period of 14 days. The results showed that low concentration of octylphenol (5 μg L-1) stimulated the maturation while high concentrations of the chemical (50 and 500 μg L-1) caused a significant mortality to the Daphnia. Besides, all the tested concentrations of octylphenol had serious impacts on fecundity and growth of the animals. Investigations on the presence, distribution, fate and toxicity of xonobiotics including octylphenol in the developing country environment are suggested for human, environmental and ecological health protection. / Những hợp chất tổng hợp đang là mối quan ngại cho con người và môi trường vì khả năng gây độc của chúng. Octylphenol là một trong những hợp chất tổng hợp được sử dụng phổ biến và thường xuyên trong những hoạt động của con người trong nhà và ngoài trời. Độc tính của octylphenol đối với thủy sinh vật, đặc biệt đối với động vật phù du (vd. Daphnia magna) mặc dù đã được nghiên cứu nhưng vẫn chưa được hiểu biết đầy đủ. Trong nghiên cứu này, chúng tôi đánh giá ảnh hưởng mãn tính của octylphenol ở các nồng độ 5, 50 và 500 μg/lít lên Daphnia magna trong thời gian 14 ngày. Kết quả cho thấy ở nồng độ octylphenol thấp (5 μg/lít) kích thích sự thành thục của sinh vật trong khi ở nồng độ cao hơn (50 và 500 μg/lít) gây chết đáng kể Daphnia. Bên cạnh đó, tất cả các nồng độ ocytlphenol dùng trong thí nghiệm gây ảnh hưởng nghiêm trọng lên sức sinh sản và sinh trưởng của sinh vật. Nghiên cứu về sự hiện diện, phân bố, phát tán và độc tính của những chất tổng hợp bao gồm octylphenol ở các nước đang phát triển nên được tiến hành vì mục tiêu bảo vệ sức khỏe con người, môi trường và hệ sinh thái.