ISSN:1310-2818    

DOI:10.1080/13102818.1992.10818670

出版商:Taylor & Francis    

年代:1992

数据来源: Taylor

摘要:

The ability of isolated pea (Pisum sativum cv. Ran 1) mesophyll protoplasts to aggregate and fuse spontaneously was examined. Aiming to define whether Ca2+released during enzymatic isolation of protoplasts and residual in the purified suspension is important for aggregation and fusion, different isolating media were used: Ca2+—free medium, buffered Ca2+—free medium, Ca2 +—free medium containing 2.5 mM EGTA, and medium containing 10 mM CaCl2. Light scattering was measured to assess aggregation and/or fusion and Arsenazo III was used to evaluate free Ca2+. Binding of Ca2+to plasmalemma was characterized by 9-Aminoac ridine fluorescence. Since light scattering of purified suspensions of protoplasts isolated in the presence of 2.5 mM EGTA was lower as compared to the other variants, a Ca2+—dependent fusion during isolation was suggested. Binding of Ca2+by 100 μM EGTA slightly reduced the light scattering of suspension of protoplasts isolated without EGTA, indicating existence of Ca2+dependent aggregation. Titration with CaCl2(up to 100 mM) completely reduced protoplasts surface potential but failed to increase the aggregation significantly. The results suggested that protoplasts fuse spontaneously in the presence of Ca2+released by the tissue during isolation. In purified suspensions residual micromolar amount of Ca2+is sufficient for aggregation.

ISSN:1310-2818    

DOI:10.1080/13102818.1992.10818671

出版商:Taylor & Francis    

年代:1992

数据来源: Taylor

摘要:

Ovaries were collected from slaughtered calves (4 month old) and examined for number and quality of fully grown oocytes. Capacity of oocytes for maturation and further development was analyzed. Mean number of oocytes per ovary was 120.3. Only 39% of all oocytes were in intact stages. After maturation for 24 h 60.8% reached the M 2 stage of meiosis. Percentages of oocytes that fertilized and cleaved after IVF were about 60 and 42%. The output of intact embryos on day 7 was 14.3%.

ISSN:1310-2818    

DOI:10.1080/13102818.1992.10818672

出版商:Taylor & Francis    

年代:1992

数据来源: Taylor

摘要:

In this study, we investigated the effects of High Voltage Transmission Lines (HVTL) on people who work and live in such areas. The study was carried out on 51 persons from 15 to 50 years of age exposed to electric field. First, we gave out a questionnaire to everybody under investigation. We established that these people most often suffer from headache, irritability, fatigue, stress and shock. Secondly, we determined 23 parameters of their blood serum. The levels of ALP, Na, Cl, total protein, albumin, Group Specific Component, ceruloplasmin and albumin/globulin ratio were found especially significant.

ISSN:1310-2818    

DOI:10.1080/13102818.1992.10818673

出版商:Taylor & Francis    

年代:1992

数据来源: Taylor

摘要:

In this study, we investigated the biological effects of RF (Radio Frequency) and microwave in terms of neurological and biochemical findings, and CD4/CD8 ratio in people that work at broadcasting and television transmitter stations. The study was carried out on 26 people from 20 to 49 years of age, occupationally exposed to nonionizing radiation. First we gave out a questionnaire consisting of 12 questions to everybody under investigation. Secondly, we determined the levels of ALT, AST, LDH, ALP, CK, phosphorus, total protein, albumin cholesterol, uric acid, urea, creatinin, Na, K, and NSE (Neuron Specific Enolase), and also CD4/CD8, albumin/globulin ratios and percentage of serum proteins. The results obtained in this study were statistically compared to a control group.

ISSN:1310-2818    

DOI:10.1080/13102818.1992.10818674

出版商:Taylor & Francis    

年代:1992

数据来源: Taylor

摘要:

This paper deals with the modelling and control of the hatch kinetic of xanthan gum, a microbial polysaccharide synthesized by Xanthomonas campestris—ITS-342, obtained from the Institute for Bioproducts, Plovdiv (Bulgaria). A nonstructure model is proposed. On this basis the attention is focussed on the synthesis of the adaptive linearizing control law with dissolved oxygen as an input action. Some simulations results are discussed.

ISSN:1310-2818    

DOI:10.1080/13102818.1992.10818675

出版商:Taylor & Francis    

年代:1992

数据来源: Taylor

摘要:

Two adaptive algorithms based oil extended Kalman filter for estimation of specific growth rateμ,concentrations of biomass X and product P for aerobic batch process of ergocriptin biosyntesis in deficiency of on-line information for state variables are synthesized. The algorithms efficiency is proved by simulation investigations on the basis of the process model. The estimation accuracies of the two algorithms are compared, the estimates obtained by one of the algorithms being compared with adaptive state observer ones. Conclusions about applicability of the proposed algorithms are made.

ISSN:1310-2818    

DOI:10.1080/13102818.1992.10818676

出版商:Taylor & Francis    

年代:1992

数据来源: Taylor