Effects of Filtered Lake Water on Colony Formation and Growth Rate inMicrocystis aeruginosaof Different Physiological Phases

2005 ◽  
Vol 20 (3) ◽  
pp. 425-429 ◽  
Author(s):  
Zhou Yang ◽  
Fanxiang Kong ◽  
Xiaoli Shi
Keyword(s):  
Growth Rate ◽  
Lake Water ◽  
Colony Formation

A modeling approach to simulate impact of climate change in lake water quality: phytoplankton growth rate assessment

1998 ◽  
Vol 37 (2) ◽  
pp. 177-185 ◽  
Author(s):  
Hany Hassan ◽  
Keisuke Hanaki ◽  
Tomonori Matsuo
Keyword(s):  
Climate Change ◽  
Water Quality ◽  
Growth Rate ◽  
Dissolved Oxygen ◽  
Lake Water ◽  
Phytoplankton Growth ◽  
Quality Data ◽  
Model Parameters ◽  
Lake Water Quality ◽  
Phytoplankton Growth Rate

Global climate change induced by increased concentrations of greenhouse gases (especially CO2) is expected to include changes in precipitation, wind speed, incoming solar radiation, and air temperature. These major climate variables directly influence water quality in lakes by altering changes in flow and water temperature balance. High concentration of nutrient enrichment and expected variability of climate can lead to periodic phytoplankton blooms and an alteration of the neutral trophic balance. As a result, dissolved oxygen levels, with low concentrations, can fluctuate widely and algal productivity may reach critical levels. In this work, we will present: 1) recent results of GCMs climate scenarios downscaling project that was held at the University of Derby, UK.; 2) current/future comparative results of a new mathematical lake eutrophication model (LEM) in which output of phytoplankton growth rate and dissolved oxygen will be presented for Suwa lake in Japan as a case study. The model parameters were calibrated for the period of 1973–1983 and validated for the period of 1983–1993. Meterologic, hydrologic, and lake water quality data of 1990 were selected for the assessment analysis. Statistical relationships between seven daily meteorological time series and three airflow indices were used as a means for downscaling daily outputs of Hadley Centre Climate Model (HadCM2SUL) to the station sub-grid scale.

scholarly journals The Effect of Plethora on Growth and Differentiation of Normal Hemopoietic Colony-Forming Cells Transplanted in Mice of Genotype W/Wv

Blood ◽  
1967 ◽  
Vol 29 (1) ◽  
pp. 102-113 ◽  
Author(s):  
J. E. TILL ◽  
L. SIMINOVITCH ◽  
E. A. McCULLOCH
Keyword(s):  
Growth Rate ◽  
Colony Formation ◽  
Granulocytic Differentiation ◽  
Additional Support ◽  
Marrow Cells

Abstract Suppression of erythropoiesis by transfusion of animals of genotype W/Wv was found to prevent the development of macroscopic spleen colonies following injection of normal coisogenic marrow cells. This inhibition of colony-formation was not due to a failure of colony-forming cells to proliferate in the absence of erythropoietic stimulation, since the growth rate of normal colony-forming cells in plethoric animals did not differ significantly from that seen in anemic hosts. It is likely that, in plethoric hosts, insufficient differentiated erythroblasts were produced to permit the development of macroscopically visible spleen colonies. Evidence was obtained that granulocytic differentiation proceeded during the growth of the transplanted colony-forming cells, and that this mode of differentiation was not affected by the suppression of erythropoiesis. These results indicate that both granulocytic differentiation and the process of selfrenewal by which colony-forming cells increase in numbers are controlled independently of the control of erythropoiesis. These experiments provide additional support for the view that colony-forming cells differ from erythropoietin-sensitive cells.

scholarly journals Modeling the impediment of methane ebullition bubbles by seasonal lake ice

2014 ◽  
Vol 11 (23) ◽  
pp. 6791-6811 ◽  
Author(s):  
S. Greene ◽  
K. M. Walter Anthony ◽  
D. Archer ◽  
A. Sepulveda-Jauregui ◽  
K. Martinez-Cruz
Keyword(s):  
Growth Rate ◽  
Lake Water ◽  
Ice Cover ◽  
Controlling Factors ◽  
Ch4 Emission ◽  
Lake Ice ◽  
Ch4 Emissions ◽  
Interior Alaska ◽  
Methane Ebullition ◽  
Significant Flux

Abstract. Microbial methane (CH4) ebullition (bubbling) from anoxic lake sediments comprises a globally significant flux to the atmosphere, but ebullition bubbles in temperate and polar lakes can be trapped by winter ice cover and later released during spring thaw. This "ice-bubble storage" (IBS) constitutes a novel mode of CH4 emission. Before bubbles are encapsulated by downward-growing ice, some of their CH4 dissolves into the lake water, where it may be subject to oxidation. We present field characterization and a model of the annual CH4 cycle in Goldstream Lake, a thermokarst (thaw) lake in interior Alaska. We find that summertime ebullition dominates annual CH4 emissions to the atmosphere. Eighty percent of CH4 in bubbles trapped by ice dissolves into the lake water column in winter, and about half of that is oxidized. The ice growth rate and the magnitude of the CH4 ebullition flux are important controlling factors of bubble dissolution. Seven percent of annual ebullition CH4 is trapped as IBS and later emitted as ice melts. In a future warmer climate, there will likely be less seasonal ice cover, less IBS, less CH4 dissolution from trapped bubbles, and greater CH4 emissions from northern lakes.

scholarly journals Modeling the impediment of methane ebullition bubbles by seasonal lake ice

2014 ◽  
Vol 11 (7) ◽  
pp. 10863-10916 ◽  
Author(s):  
S. Greene ◽  
K. M. Walter Anthony ◽  
D. Archer ◽  
A. Sepulveda-Jauregui ◽  
K. Martinez-Cruz
Keyword(s):  
Growth Rate ◽  
Lake Water ◽  
Ice Cover ◽  
Controlling Factors ◽  
Ch4 Emission ◽  
Lake Ice ◽  
Ch4 Emissions ◽  
Interior Alaska ◽  
Methane Ebullition ◽  
Significant Flux

Abstract. Microbial methane (CH4) ebullition (bubbling) from anoxic lake sediments comprises a globally significant flux to the atmosphere, but ebullition bubbles in temperate and polar lakes can be trapped by winter ice cover and later released during spring thaw. This "ice-bubble storage" (IBS) constitutes a novel mode of CH4 emission. Before bubbles are encapsulated by downward-growing ice, some of their CH4 dissolves into the lake water, where it may be subject to oxidation. We present field characterization and a model of the annual CH4 cycle in Goldstream Lake, a thermokarst (thaw) lake in interior Alaska. We find that summertime ebullition dominates annual CH4 emissions to the atmosphere. Eighty percent of CH4 in bubbles trapped by ice dissolves into the lake water column in winter, and about half of that is oxidized. The ice growth rate and the magnitude of the CH4 ebullition flux are important controlling factors of bubble dissolution. Seven percent of annual ebullition CH4 is trapped as IBS and later emitted as ice melts. In a future warmer climate, there will likely be less seasonal ice cover, less IBS, less CH4 dissolution from trapped bubbles, and greater CH4 emissions from northern lakes.

scholarly journals Suppression of Estrogen Receptor Alpha Inhibits Cell Proliferation, Differentiation and Enhances the Chemosensitivity of P53-Positive U2OS Osteosarcoma Cell

2021 ◽  
Vol 22 (20) ◽  
pp. 11238
Author(s):  
Jir-You Wang ◽  
Chao-Ming Chen ◽  
Cheng-Fong Chen ◽  
Po-Kuei Wu ◽  
Wei-Ming Chen
Keyword(s):  
Cell Cycle ◽  
Growth Rate ◽  
Estrogen Receptor ◽  
Cell Line ◽  
Colony Formation ◽  
Estrogen Receptor Alpha ◽  
Receptor Alpha ◽  
Chemical Treatments ◽  
U2os Cells

Osteosarcoma is a highly malignant musculoskeletal tumor that is commonly noticed in adolescent children, young children, and elderly adults. Due to advances in surgery, chemotherapy and imaging technology, survival rates have improved to 70–80%, but chemical treatments do not enhance patient survival; in addition, the survival rate after chemical treatments is still low. The most obvious clinical feature of osteosarcoma is new bone formation, which is called “sun burst”. Estrogen receptor alpha (ERα) is an essential feature of osteogenesis and regulates cell growth in various tumors, including osteosarcoma. In this study, we sought to investigate the role of ERα in osteosarcoma and to determine if ERα can be used as a target to facilitate the chemosensitivity of osteosarcoma to current treatments. The growth rate of each cell clone was assayed by MTT and trypan blue cell counting, and cell cycle analysis was conducted by flow cytometry. Osteogenic differentiation was induced by osteogenic induction medium and quantified by ARS staining. The effects of ERα on the chemoresponse of OS cells treated with doxorubicin were evaluated by colony formation assay. Mechanistic studies were conducted by examining the levels of proteins by Western blot. The role of ERα on OS prognosis was investigated by an immunohistochemical analysis of OS tissue array. The results showed an impaired growth rate and a decreased osteogenesis ability in the ERα-silenced P53(+) OS cell line U2OS, but not in P53(−) SAOS2 cells, compared with the parental cell line. Cotreatment with tamoxifen, an estrogen receptor inhibitor, increased the sensitivity to doxorubicin, which decreased the colony formation of P53(+) U2OS cells. Cell cycle arrest in the S phase was observed in P53(+) U2OS cells cotreated with low doses of doxorubicin and tamoxifen, while increased levels of apoptosis factors indicated cell death. Moreover, patients with ER−/P53(+) U2OS showed better chemoresponse rates (necrosis rate > 90%) and impaired tumor sizes, which were compatible with the findings of basic research. Taken together, ERα may be a potential target of the current treatments for osteosarcoma that can control tumor growth and improve chemosensitivity. In addition, the expression of ERα in osteosarcoma can be a prognostic factor to predict the response to chemotherapy.

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