Dispersion of Oxides on HZSM-5 and Threshold Effect on Shape-Selective Methylation of Toluene

1999 ◽  
pp. 188-200
Author(s):  
Youchang Xie ◽  
Biying Zhao ◽  
Xiangyun Long ◽  
Youqi Tang
Keyword(s):  
Threshold Effect ◽  
Shape Selective

Hyperstimulation of the immune system as a cause of autoimmune diseases

2020 ◽  
Vol 75 (3) ◽  
pp. 204-213
Author(s):  
Varvara A. Ryabkova ◽  
Leonid P. Churilov ◽  
Yehuda Shoenfeld
Keyword(s):  
Immune System ◽  
Autoimmune Diseases ◽  
Genetic Basis ◽  
Threshold Model ◽  
Subsequent Development ◽  
Threshold Effect ◽  
Successful Management ◽  
Polygenic Inheritance ◽  
Autoimmune Pathology ◽  
The Common

The pathogenesis of autoimmune diseases is very complex and multi-factorial. The concept of Mosaics of Autoimmunity was introduced to the scientific community 30 years ago by Y. Shoenfeld and D.A. Isenberg, and since then new tiles to the puzzle are continuously added. This concept specifies general pathological ideas about the multifactorial threshold model for polygenic inheritance with a threshold effect by the action of a number of external causal factors as applied to the field of autoimmunology. Among the external factors that can excessively stimulate the immune system, contributing to the development of autoimmune reactions, researchers are particularly interested in chemical substances, which are widely used in pharmacology and medicine. In this review we highlight the autoimmune dynamics i.e. a multistep pathogenesis of autoimmune diseases and the subsequent development of lymphoma in some cases. In this context several issues are addressed namely, genetic basis of autoimmunity; environmental immunostimulatory risk factors; gene/environmental interaction; pre-clinical autoimmunity with the presence of autoantibodies; and the mechanisms, underlying lymphomagenesis in autoimmune pathology. We believe that understanding the common model of the pathogenesis of autoimmune diseases is the first step to their successful management.

Shape-Selective Alkylation of Toluene with Methanol over Modified Nano-scale HZSM-5 Zeolite

2014 ◽  
Vol 32 (7) ◽  
pp. 1280-1286 ◽  
Author(s):  
Zhiping ZHANG ◽  
Yan ZHAO ◽  
Hongyu WU ◽  
Wei TAN ◽  
Xiangsheng WANG ◽  
...  
Keyword(s):  
Nano Scale ◽  
Shape Selective ◽  
Selective Alkylation

scholarly journals The genetics of catalase in Drosophila melanogaster: isolation and characterization of acatalasemic mutants.

Genetics ◽  
1989 ◽  
Vol 122 (3) ◽  
pp. 643-652 ◽  
Author(s):  
W J Mackay ◽  
G C Bewley
Keyword(s):  
Drosophila Melanogaster ◽  
Free Radical ◽  
Catalase Activity ◽  
Oxygen Toxicity ◽  
Threshold Effect ◽  
Culture Conditions ◽  
Free Radical Damage ◽  
Isolation And Characterization ◽  
Standard Culture ◽  
Hypomorphic Alleles

Abstract Activated oxygen species have been demonstrated to be the important agents in oxygen toxicity by disrupting the structural and functional integrity of cells through lipid peroxidation events, DNA damage and protein inactivation. The biological consequences of free radical damage have long been hypothesized to be a causal agent in many aging-related diseases. Catalase (H2O2:H2O2 oxidoreductase; EC 1.15.1.1) is one of several enzymes involved in the scavenging of oxygen free radicals and free radical derivatives. The structural gene for catalase in Drosophila melanogaster has been localized to region 75D1-76A on chromosome 3L by dosage responses to segmental aneuploidy. This study reports the isolation of a stable deficiency, Df(3L)CatDH104(75C1-2;75F1), that uncovers the catalase locus and the subsequent isolation of six acatalasemic mutants. All catalase mutants are viable under standard culture conditions and recessive lethal mutations within the 75Cl-F1 interval have been shown not to affect catalase activity. Two catalase mutations are amorphic while four are hypomorphic alleles of the Cat+ locus. The lack of intergenic complementation between the six catalase mutations strongly suggests that there is only one functional gene in Drosophila. One acatalesemic mutation was mapped to position 3-47.0 which resides within the catalase dosage sensitive region. While complete loss of catalase activity confers a severe viability effect, residual levels are sufficient to restore viability to wild type levels. These results suggest a threshold effect for viability and offer an explanation for the general lack of phenotypic effects associated with the known mammalian acatalasemics.

scholarly journals Threshold Effects of Infectious Disease Outbreaks on Livestock Prices: Cases of African Swine Fever and Avian Influenza in South Korea

2021 ◽  
Vol 11 (11) ◽  
pp. 5114
Author(s):  
Hyung-Chul Rah ◽  
Hyeon-Woong Kim ◽  
Aziz Nasridinov ◽  
Wan-Sup Cho ◽  
Seo-Hwa Choi ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Infectious Diseases ◽  
Disease Outbreaks ◽  
African Swine Fever ◽  
Threshold Effect ◽  
Impact Response ◽  
Threshold Effects ◽  
Infectious Disease Outbreaks ◽  
Retail Prices ◽  
The Impact

In this paper we demonstrate the threshold effects of infectious diseases on livestock prices. Daily retail prices of pork and chicken were used as structured data; news and SNS mentions of African Swine Fever (ASF) and Avian Influenza (AI) were used as unstructured data. Models were tested for the threshold effects of disease-related news and SNS frequencies, specifically those related to ASF and AI, on the retail prices of pork and chicken, respectively. The effects were found to exist, and the values of ASF-related news on pork prices were estimated to be −9 and 8, indicating that the threshold autoregressive (TAR) model can be divided into three regimes. The coefficients of the ASF-related SNS frequencies on pork prices were 1.1666, 0.2663 and −0.1035 for regimes 1, 2 and 3, respectively, suggesting that pork prices increased by 1.1666 Korean won in regime 1 when ASF-related SNS frequencies increased. To promote pork consumption by SNS posts, the required SNS frequencies were estimated to have impacts as great as one standard deviation in the pork price. These values were 247.057, 1309.158 and 2817.266 for regimes 1, 2 and 3, respectively. The impact response periods for pork prices were estimated to last 48, 6, and 8 days for regimes 1, 2 and 3, respectively. When the prediction accuracies of the TAR and autoregressive (AR) models with regard to pork prices were compared for the root mean square error, the prediction accuracy of the TAR model was found to be slightly better than that of the AR. When the threshold effect of AI-related news on chicken prices was tested, a linear relationship appeared without a threshold effect. These findings suggest that when infectious diseases such as ASF occur for the first time, the impact on livestock prices is significant, as indicated by the threshold effect and the long impact response period. Our findings also suggest that the impact on livestock prices is not remarkable when infectious diseases occur multiple times, as in the case of AI. To date, this study is the first to suggest the use of SNS to promote meat consumption.

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