From June 2003 to June 2004, an investigation on the life cycle, production and trophic basis of dominant species of macrozoobenthos community in a second-order river of the Hanjiang River basin, Hubei, China was card...From June 2003 to June 2004, an investigation on the life cycle, production and trophic basis of dominant species of macrozoobenthos community in a second-order river of the Hanjiang River basin, Hubei, China was carded out. The results showed that the dominant species Leptophlebia sp. and Ephemera sp. appeared to develop two generations per year, and there was a small overlap in the two generations of both species. The pupation of Leptophlebia sp. mainly occurred in autumn and winter, while pupation of Ephemera sp. mainly took place in summer and winter. The standing stocks of the Leptophlebia sp. population and Ephemera sp. population had two peaks in a year. The cohort production and cohort P/B ratio of the Leptophlebia sp. population estimated by size frequency method were 19.018 1 g/m^2.a and 5.7 respectively, while its annual production and P/B ratio were 38.036 2 g/m^2.a and 11.4. The cohort production and cohort P/B ratio of the Ephemera sp. population were 38.015 9 g/m^2.a and 5.9, while its annual production and P/B ratio were 76.031 8 g/m^2.a and 11.8.展开更多
Sustainability and eco-friendliness have both engendered research on alternative replacement of fossil fuel. This study was aimed at determining the effects of varying levels of glucose (10 ~ 40 g/L), and glycerol (0....Sustainability and eco-friendliness have both engendered research on alternative replacement of fossil fuel. This study was aimed at determining the effects of varying levels of glucose (10 ~ 40 g/L), and glycerol (0.25 ~ 1.0 mL/L) on the heterotrophic and mixotrophic growth and lipid production by Dictyosphaerium sp. The microalga was cultivated in 2000 mL amber-coloured bottles each containing 1000 mL of a sterile modified BG-11 medium at pH of 7.3. Each bottle was inoculated with a one-week-old pure culture of the isolate (inoculum ratio = 15%) and incubated in the dark at room temperature (30°C ± 2°C) for 10 d. Dictyosphaerium sp. showed the ability to grow heterotrophically and mixotrophically on glucose and on glycerol as a sole carbon substrates. Biomass productivity and specific growth rates did not vary when the initial medium glucose was varied. Lipid accumulation was not dependent on the initial medium glycerol contents. The mean lipid content and productivity of the organism in the present study were high enough to be utilised for industrial processes. Growth and lipid accumulations were better in mixotrophic cultures than both heterotrophic and autotrophic. However, both were better than autotrophic. The percentage compositions of the major fatty acids from Dictyosphaerium sp. grown under different culture conditions show at least five components each. The carbon skeletons eluted ranged from C14 to C22. Oleic acid was a major component of all the fatty acids, which confirm the suitability of the use of the oil for biodiesel production.展开更多
With the rise of live streaming on social media, platforms like Facebook, Instagram, and YouTube have become powerful business tools. They enable users to share live videos, fostering direct connections between busine...With the rise of live streaming on social media, platforms like Facebook, Instagram, and YouTube have become powerful business tools. They enable users to share live videos, fostering direct connections between businesses and their customers. This critical literature review paper explores the impact of live streaming on businesses, focusing on its role in attracting and satisfying consumers by promoting products tailored to their needs and wants. It emphasizes live streaming’s crucial role in engaging customers, a key to business growth. The study also provides viable strategies for businesses to leverage live streaming for growth and customer engagement, underscoring its importance in the business landscape.展开更多
Mayflies constitute a major part of macroinvertebrate biomass and production in Iotic ecosystems, and play an important role in material cycle and energy flow. There are more than 250 species of mayflies in rivers and...Mayflies constitute a major part of macroinvertebrate biomass and production in Iotic ecosystems, and play an important role in material cycle and energy flow. There are more than 250 species of mayflies in rivers and streams of China. In order to learn their ecological functions, an investigation on life cycle, production and trophic basis of dominant species of mayflies in a second-order branch of Hanjiang River basin, Hubei, China was carried out during June 2003 to June 2004. The results showed that the dominant mayfly species Epeorus sp. and Caenis sp. developed two generations per year; in term of Epeorus sp., pupation mainly occurred in spring and then from late summer to early autumn, while Caenis sp. pupated in spring and autumn. The abundance and biomass of the Epeorus sp. population peaked twice (1 226 ind/m^2, 3.142 5g/m^2) in April and June. Caenis sp. also had two peaks (307ind/m^2, 1.590 g/m^2), but in February and June. Cohort production and cohort P/B ratio of Epeorus sp. were 161.009 g/m2 wet weight and 7.7, respectively, and annual production and P/B ratio were 267.46g/m^2.a wet weight and 15.4, respectively; cohort production and P/B ratio of Caenis sp. were 26.7995g/m^2 wet weight and 4.7, its annual production and P/B ratio were 53.60 g/m2.a wet weight and 9.4, respectively. For Epeorus sp., the proportions contributing to secondary production of the main food types were: amorphous detritus, 33.46%; fungi, 10.83%; vascular plant detritus, 1.80%; diatoms, 53.90%; for Caenis sp., the proportions were 70.79%, 6.90%, 3.52% and 18.77%, respectively.展开更多
The production dynamics and trophic basis of 7 dominant species of chironomids were investigated in the area of a second-order river of the Hanjiang River basin, in central China from June 2003 to June 2004. The resul...The production dynamics and trophic basis of 7 dominant species of chironomids were investigated in the area of a second-order river of the Hanjiang River basin, in central China from June 2003 to June 2004. The results showed that Tvetenia discoloripes was by far the most abundant chironomid, dominating the overall standing stock of the taxa. In terms of life cycle, Chaetocladius sp., Eukiefferiella potthasti and T. discoloripes developed 1 generation a year, whereas Microtendipes sp. and Pagastia sp. developed two, while Pentaneura sp. and Polypedilum sp. developed three. T. discoloripes was the most productive chironomid with 120.305 8 g/m2.a, Pentaneura sp. and E. potthasti had relatively high production values of >17 g/m2.a, and the rest were <10 g/m2.a. All the production temporal variation tended to follow biomass patterns. T. discoloripes, Chaetocladius sp. and Pagastia sp. concentrated most of their production in winter, whereas E. potthasti, Pentaneura sp. and Polypedilum sp. had relatively higher production throughout the year. Only Microtendipes sp. had a production that peaked in summer. The overlap in temporal distribution of production among the chironomid species was generally high (>0.5), especially for filter-collectors Microtendipes sp., Chaetocladius sp., Chaetocladius sp., T. discoloripes and Pagastia sp. All species except Pentaneura sp. consumed a large portion of amorphous detritus, constituting more than 90% of their diets, and contributing nearly 90% to their secondary production. All the 7 chironomids represent obvious adaptation to local highly variable climate in summer and autumn in life cycle pattern, production dynamics, and food type.展开更多
Decapod crustaceans are one of the dominant faunal components of most tropical streams. However, several aspects concerning their biology and ecology are poorly known, especially in intertropical Africa. The aim of th...Decapod crustaceans are one of the dominant faunal components of most tropical streams. However, several aspects concerning their biology and ecology are poorly known, especially in intertropical Africa. The aim of this study was to investigate the production of the atyid shrimps in Masanga Mabe, an equatorial lowland forest stream of Kisangani region. Samplings were undertaken biweekly from September 2000 to August 2003 with Surber net in four study sites. A total of 14,878 atyid shrimps specimens were sampled, measured for carapace length, weighted and identified. Atyid production was estimated by size frequency method according to sites (1, 2 and 3). Atyid composition showed the existence of two species: C africana (Caridina africana) Kingsley 1882 and C togoensis (Caridina togoensis) Hilgendorf 1893. Specific production ranged from 1.35 g·DM·m^-2-year^-1 (grams dry mass per square meter per year) to 8.4 g·DM·m^-2-year^-1 for C. africana and 0.95 g·DM·m^-2-year^-1 to 4.55 g·DM·m^-2-year^-1 for C togoensis. Mean annual P/B ratios varied from 3.89 year1 to 4.37 year1 for C africana and from 3.83 year^-1 to 3.98 year^-1 for C togoensis.展开更多
As a way of making algal feedstock feasible for biofuel production, simulta<span>neous utilization of microalga <i>Dictyosphaerium</i> sp. LC172264 for cassava</span> wastewater remediation and...As a way of making algal feedstock feasible for biofuel production, simulta<span>neous utilization of microalga <i>Dictyosphaerium</i> sp. LC172264 for cassava</span> wastewater remediation and accumulation of lipids for biodiesel production was investigated. The algal biomass, lipid contents and composition were measured from the autotrophic, heterotrophic and mixotrophic cultured algal cells. Physicochemical parameters of the cassava wastewater and bioremediation potentials were measured. Biodiesel properties were deduced and compared with the standards. The results showed that mixotrophic culture was the best for both biomass accumulation (1.022 g/L) and lipid contents (24.53%). Irrespective of the culture condition, the predominant fatty acids were similar and included 11-Octadecenoic acid (vaccenic acid (C<sub>19</sub>H<sub>36</sub>O<sub>2</sub>), oleic acid (C<sub>18</sub>H<sub>34</sub>O<sub>2</sub>) and 14-methyl pentadecanoic acid (isopalmitic acid (C<sub>17</sub>H<sub>34</sub>O<sub>2</sub>). The percentage reduction of total dissolved solids was 79.32% and 89.78% for heterotrophy and mixotrophy respectively. Biochemical oxygen demand was 72.95% and 89.35%, chemical oxygen demand was 72.19% and 84.03% whereas cyanide contents reduced from the initial value of 450 mg/L to 93.105 (79.31%) and 85.365 mg/L (81.03%) respectively. <i>Dictyosphaerium</i> sp. showed good growth and lipid production under mixotrophic condition and produced good quality biodiesel under the three cultivation modes. Even though both mixotrophic and heterotrophic conditions had good promise of cassava wastewater remediation by <i>Dictyosphaerium</i> sp., mixotrophy showed superiority.展开更多
文摘From June 2003 to June 2004, an investigation on the life cycle, production and trophic basis of dominant species of macrozoobenthos community in a second-order river of the Hanjiang River basin, Hubei, China was carded out. The results showed that the dominant species Leptophlebia sp. and Ephemera sp. appeared to develop two generations per year, and there was a small overlap in the two generations of both species. The pupation of Leptophlebia sp. mainly occurred in autumn and winter, while pupation of Ephemera sp. mainly took place in summer and winter. The standing stocks of the Leptophlebia sp. population and Ephemera sp. population had two peaks in a year. The cohort production and cohort P/B ratio of the Leptophlebia sp. population estimated by size frequency method were 19.018 1 g/m^2.a and 5.7 respectively, while its annual production and P/B ratio were 38.036 2 g/m^2.a and 11.4. The cohort production and cohort P/B ratio of the Ephemera sp. population were 38.015 9 g/m^2.a and 5.9, while its annual production and P/B ratio were 76.031 8 g/m^2.a and 11.8.
文摘Sustainability and eco-friendliness have both engendered research on alternative replacement of fossil fuel. This study was aimed at determining the effects of varying levels of glucose (10 ~ 40 g/L), and glycerol (0.25 ~ 1.0 mL/L) on the heterotrophic and mixotrophic growth and lipid production by Dictyosphaerium sp. The microalga was cultivated in 2000 mL amber-coloured bottles each containing 1000 mL of a sterile modified BG-11 medium at pH of 7.3. Each bottle was inoculated with a one-week-old pure culture of the isolate (inoculum ratio = 15%) and incubated in the dark at room temperature (30°C ± 2°C) for 10 d. Dictyosphaerium sp. showed the ability to grow heterotrophically and mixotrophically on glucose and on glycerol as a sole carbon substrates. Biomass productivity and specific growth rates did not vary when the initial medium glucose was varied. Lipid accumulation was not dependent on the initial medium glycerol contents. The mean lipid content and productivity of the organism in the present study were high enough to be utilised for industrial processes. Growth and lipid accumulations were better in mixotrophic cultures than both heterotrophic and autotrophic. However, both were better than autotrophic. The percentage compositions of the major fatty acids from Dictyosphaerium sp. grown under different culture conditions show at least five components each. The carbon skeletons eluted ranged from C14 to C22. Oleic acid was a major component of all the fatty acids, which confirm the suitability of the use of the oil for biodiesel production.
文摘With the rise of live streaming on social media, platforms like Facebook, Instagram, and YouTube have become powerful business tools. They enable users to share live videos, fostering direct connections between businesses and their customers. This critical literature review paper explores the impact of live streaming on businesses, focusing on its role in attracting and satisfying consumers by promoting products tailored to their needs and wants. It emphasizes live streaming’s crucial role in engaging customers, a key to business growth. The study also provides viable strategies for businesses to leverage live streaming for growth and customer engagement, underscoring its importance in the business landscape.
文摘Mayflies constitute a major part of macroinvertebrate biomass and production in Iotic ecosystems, and play an important role in material cycle and energy flow. There are more than 250 species of mayflies in rivers and streams of China. In order to learn their ecological functions, an investigation on life cycle, production and trophic basis of dominant species of mayflies in a second-order branch of Hanjiang River basin, Hubei, China was carried out during June 2003 to June 2004. The results showed that the dominant mayfly species Epeorus sp. and Caenis sp. developed two generations per year; in term of Epeorus sp., pupation mainly occurred in spring and then from late summer to early autumn, while Caenis sp. pupated in spring and autumn. The abundance and biomass of the Epeorus sp. population peaked twice (1 226 ind/m^2, 3.142 5g/m^2) in April and June. Caenis sp. also had two peaks (307ind/m^2, 1.590 g/m^2), but in February and June. Cohort production and cohort P/B ratio of Epeorus sp. were 161.009 g/m2 wet weight and 7.7, respectively, and annual production and P/B ratio were 267.46g/m^2.a wet weight and 15.4, respectively; cohort production and P/B ratio of Caenis sp. were 26.7995g/m^2 wet weight and 4.7, its annual production and P/B ratio were 53.60 g/m2.a wet weight and 9.4, respectively. For Epeorus sp., the proportions contributing to secondary production of the main food types were: amorphous detritus, 33.46%; fungi, 10.83%; vascular plant detritus, 1.80%; diatoms, 53.90%; for Caenis sp., the proportions were 70.79%, 6.90%, 3.52% and 18.77%, respectively.
基金Supported by the National Natural Sciences Foundation of China (Nos 30640024 and 30270278).
文摘The production dynamics and trophic basis of 7 dominant species of chironomids were investigated in the area of a second-order river of the Hanjiang River basin, in central China from June 2003 to June 2004. The results showed that Tvetenia discoloripes was by far the most abundant chironomid, dominating the overall standing stock of the taxa. In terms of life cycle, Chaetocladius sp., Eukiefferiella potthasti and T. discoloripes developed 1 generation a year, whereas Microtendipes sp. and Pagastia sp. developed two, while Pentaneura sp. and Polypedilum sp. developed three. T. discoloripes was the most productive chironomid with 120.305 8 g/m2.a, Pentaneura sp. and E. potthasti had relatively high production values of >17 g/m2.a, and the rest were <10 g/m2.a. All the production temporal variation tended to follow biomass patterns. T. discoloripes, Chaetocladius sp. and Pagastia sp. concentrated most of their production in winter, whereas E. potthasti, Pentaneura sp. and Polypedilum sp. had relatively higher production throughout the year. Only Microtendipes sp. had a production that peaked in summer. The overlap in temporal distribution of production among the chironomid species was generally high (>0.5), especially for filter-collectors Microtendipes sp., Chaetocladius sp., Chaetocladius sp., T. discoloripes and Pagastia sp. All species except Pentaneura sp. consumed a large portion of amorphous detritus, constituting more than 90% of their diets, and contributing nearly 90% to their secondary production. All the 7 chironomids represent obvious adaptation to local highly variable climate in summer and autumn in life cycle pattern, production dynamics, and food type.
文摘Decapod crustaceans are one of the dominant faunal components of most tropical streams. However, several aspects concerning their biology and ecology are poorly known, especially in intertropical Africa. The aim of this study was to investigate the production of the atyid shrimps in Masanga Mabe, an equatorial lowland forest stream of Kisangani region. Samplings were undertaken biweekly from September 2000 to August 2003 with Surber net in four study sites. A total of 14,878 atyid shrimps specimens were sampled, measured for carapace length, weighted and identified. Atyid production was estimated by size frequency method according to sites (1, 2 and 3). Atyid composition showed the existence of two species: C africana (Caridina africana) Kingsley 1882 and C togoensis (Caridina togoensis) Hilgendorf 1893. Specific production ranged from 1.35 g·DM·m^-2-year^-1 (grams dry mass per square meter per year) to 8.4 g·DM·m^-2-year^-1 for C. africana and 0.95 g·DM·m^-2-year^-1 to 4.55 g·DM·m^-2-year^-1 for C togoensis. Mean annual P/B ratios varied from 3.89 year1 to 4.37 year1 for C africana and from 3.83 year^-1 to 3.98 year^-1 for C togoensis.
文摘As a way of making algal feedstock feasible for biofuel production, simulta<span>neous utilization of microalga <i>Dictyosphaerium</i> sp. LC172264 for cassava</span> wastewater remediation and accumulation of lipids for biodiesel production was investigated. The algal biomass, lipid contents and composition were measured from the autotrophic, heterotrophic and mixotrophic cultured algal cells. Physicochemical parameters of the cassava wastewater and bioremediation potentials were measured. Biodiesel properties were deduced and compared with the standards. The results showed that mixotrophic culture was the best for both biomass accumulation (1.022 g/L) and lipid contents (24.53%). Irrespective of the culture condition, the predominant fatty acids were similar and included 11-Octadecenoic acid (vaccenic acid (C<sub>19</sub>H<sub>36</sub>O<sub>2</sub>), oleic acid (C<sub>18</sub>H<sub>34</sub>O<sub>2</sub>) and 14-methyl pentadecanoic acid (isopalmitic acid (C<sub>17</sub>H<sub>34</sub>O<sub>2</sub>). The percentage reduction of total dissolved solids was 79.32% and 89.78% for heterotrophy and mixotrophy respectively. Biochemical oxygen demand was 72.95% and 89.35%, chemical oxygen demand was 72.19% and 84.03% whereas cyanide contents reduced from the initial value of 450 mg/L to 93.105 (79.31%) and 85.365 mg/L (81.03%) respectively. <i>Dictyosphaerium</i> sp. showed good growth and lipid production under mixotrophic condition and produced good quality biodiesel under the three cultivation modes. Even though both mixotrophic and heterotrophic conditions had good promise of cassava wastewater remediation by <i>Dictyosphaerium</i> sp., mixotrophy showed superiority.