Mathematics and Biological Process of Skin Pigmentation

2016 ◽  
pp. 87-116 ◽  
Keyword(s):  
Biological Process ◽  
Skin Pigmentation

Ultrastructure of melanocyte-keratinocyte interactions and pigment transfer in vitro

1978 ◽  
Vol 36 (2) ◽  
pp. 650-651
Author(s):  
Raul I. Garcia ◽  
Evelyn A. Flynn ◽  
George Szabo
Keyword(s):  
Direct Injection ◽  
Skin Pigmentation ◽  
Freeze Fracture ◽  
Pigment Granule ◽  
Time Lapse ◽  
Ultrastructural Level ◽  
Lanthanum Tracer ◽  
A Cell

Skin pigmentation in mammals involves the interaction of epidermal melanocytes and keratinocytes in the structural and functional unit known as the Epidermal Melanin Unit. Melanocytes(M) synthesize melanin within specialized membrane-bound organelles, the melanosome or pigment granule. These are subsequently transferred by way of M dendrites to keratinocytes(K) by a mechanism still to be clearly defined. Three different, though not necessarily mutually exclusive, mechanisms of melanosome transfer have been proposed: cytophagocytosis by K of M dendrite tips containing melanosomes, direct injection of melanosomes into the K cytoplasm through a cell-to-cell pore or communicating channel formed by localized fusion of M and K cell membranes, release of melanosomes into the extracellular space(ECS) by exocytosis followed by K uptake using conventional phagocytosis. Variability in methods of transfer has been noted both in vivo and in vitro and there is evidence in support of each transfer mechanism. We Have previously studied M-K interactions in vitro using time-lapse cinemicrography and in vivo at the ultrastructural level using lanthanum tracer and freeze-fracture.

Skin pigmentation and chlorpromazine

JAMA ◽  
1965 ◽  
Vol 194 (6) ◽  
pp. 670-672 ◽  
Author(s):  
A. S. Zelickson
Keyword(s):  
Skin Pigmentation

Изучение отклика дегидрогеназной активности ила на изменение технологических параметров работы аэротенка

2020 ◽  
Author(s):  
N. Zaletova ◽  
S. Zaletov
Keyword(s):  
Wastewater Treatment ◽  
Dehydrogenase Activity ◽  
Biological Treatment ◽  
Biological Process ◽  
Organic Load ◽  
Treatment Processes ◽  
Mode Of Operation ◽  
Concentrated Solution ◽  
Available Information ◽  
Complicated Mechanism

Биологический метод очистки сточных вод представляет собой сложный многокомпонентный процесс, ключевой составляющей которого является работа ферментной системы. Известно, что одним из важнейших ферментов, обеспечивающих биологический процесс, являются дегидрогеназы. Полностью сложнейший механизм действия ферментов до конца пока не раскрыт, однако в практике контроля процессов биологической очистки используется показатель дегидрогеназной активности ила. Результаты исследований позволили дополнить имеющуюся информацию фактическими данными о взаимообусловленности уровня дегидрогеназной активности ила и показателей отдельных технологических параметров биологической очистки. Показано, что режим работы аэротенков (нагрузка на ил, доза активного ила и др.) и величина показателей исходной дегидрогеназной активности и дегидрогеназной активности этого же образца ила со слабо концентрированным раствором (ДАИН2О) связаны между собой и зависят от нагрузки на ил по органическим веществам. Полученные результаты исследования могут быть использованы для контроля биологического процесса очистки сточных вод.The biological method of wastewater treatment is a comprehensive multicomponent process the activities of the enzyme system being the key component of it. It is known that dehydrogenases have been one of the most important enzymes the ensure the biological process. The complicated mechanism of the action of enzymes has not been fully described so far however, in the practice of monitoring biological treatment processes, an indicator of the dehydrogenase activity of sludge is used. The research results provided for supplementing the available information with actual data on the interdependence of the level of dehydrogenase activity of sludge and indicators of individual process parameters of biological treatment. It was shown that the mode of operation of aeration tanks (organic matter load on sludge, dose of activated sludge, etc.) and the values of the initial dehydrogenase activity and dehydrogenase activity of the same sludge sample with weakly concentrated solution (DASН2О) are interconnected and depend on the organic load on sludge. The results of the study can be used to control the biological process of wastewater treatment.The biological method of wastewater treatment is a comprehensive multicomponent process the activities of the enzyme system being the key component of it. It is known that dehydrogenases have been one of the most important enzymes the ensure the biological process. The complicated mechanism of the action of enzymes has not been fully described so far however, in the practice of monitoring biological treatment processes, an indicator of the dehydrogenase activity of sludge is used. The research results provided for supplementing the available information with actual data on the interdependence of the level of dehydrogenase activity of sludge and indicators of individual process parameters of biological treatment. It was shown that the mode of operation of aeration tanks (organic matter load on sludge, dose of activated sludge, etc.) and the values of the initial dehydrogenase activity and dehydrogenase activity of the same sludge sample with weakly concentrated solution (DASН2О) are interconnected and depend on the organic load on sludge. The results of the study can be used to control the biological process of wastewater treatment.

Impact of Iron-Oxide Containing Formulations Against Visible Light-Induced Skin Pigmentation in Skin of Color Individuals

2020 ◽  
Vol 19 (7) ◽  
pp. 712-717 ◽  
Author(s):  
Hawasatu Dumbuya ◽  
Pearl Grimes ◽  
Stephen Lynch ◽  
Kalli Ji ◽  
Manisha Brahmachary ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Visible Light ◽  
Skin Pigmentation

Suivi du fonctionnement d'une station d'epuration associant physico-chimie et biofiltration = Metabief (France)

1990 ◽  
Vol 22 (1-2) ◽  
pp. 251-259 ◽  
Author(s):  
R. Pujol
Keyword(s):  
Organic Matter ◽  
Biological Process ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Cold Temperatures ◽  
Biological Sludge ◽  
Physico Chemical ◽  
Total Plant ◽  
Sludge Characteristic

The sewage treatment plant of Metabief (East of France) has been monitored during three weeks in winter 1988. The treatment associates a physico-chemical treatment with a biological process of biofiltration. The first step eliminates about 60 % of the organic matter (COD and BOD). The biofliters improve the treatment removing 60 % of COD influent and 65 % of TSS. The process is efficient (N excepted) under conditions of the experiment but nitrification is limited by cold temperatures (< 10°C). Important results related to biological sludge product are presented (sludge characteristic, microscopic data, sludge production). Power consumption of biofliters represents 70 % of the total plant needs. Adequate control of washing cycles and close survey of numerous movable devices are of the utmost importance to guarantee the proper operating of biofliters.

Approach to the Reforms in Nightsoil Treatment Process Introduced Abroad

1991 ◽  
Vol 24 (5) ◽  
pp. 189-196 ◽  
Author(s):  
S. B. Guo ◽  
R. Z. Chen ◽  
G. Li ◽  
H. Y. Shoichi
Keyword(s):  
Treatment Cost ◽  
Treatment Process ◽  
Biological Process ◽  
Treatment Plant ◽  
Plant Performance ◽  
First Year ◽  
Original Design ◽  
Effluent Quality ◽  
Public Toilets

In 1987 Guangzhou Liede Nightsoil Treatment Plant started commissioning. The purpose of the plant is to dispose of 400 tons of nightsoi1 from city public toilets per day. In the first year of the commissioning a biological process was basically used according to the original design made by a Danish company. Practically it has been proved that the design is effective. The process can reduce BOD from 3800 mg/l to about 133 mg/l, or by approximately 96.5 percent. The performance of the sludge digester system is satisfactory. Because the primary investigation on characteristics of the nightsoil was insufficient there were some problems raised during the commissioning. So in the first year the effluent failed to achieve the desired quality. After the analysis of the plant performance some necessary reforms have been carried out. Now the effluent quality can stably meet the national discharge limits and the treatment cost decreases.

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