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41.
42.
SK Shaheenur Islam Holy Akwar Md. Mehedi Hossain Md. Abu Sufian Md. Zakiul Hasan Shovon Chakma Tongkorn Meeyam Warangkhana Chaisowwong Veerasak Punyapornwithaya Nitish C. Debnath Eric Brum Duangporn Pichpol 《Zoonoses and public health》2020,67(6):658-672
Analysis of environmental samples obtained from the Live Poultry Markets (LPMs) of Dhaka City, Bangladesh, has revealed that the highest degree of prevalence of highly pathogenic avian influenza A (HPAI, H5N1), besides other subtypes of the LPAI virus, poses the plausible risk of transmission of these viruses between human and poultry species. The present study was conducted using the OIE risk analysis framework to assess the risk level of each pathway successively. The estimated risk parameters were integrated towards to obtain the overall risk level for each specific HPAI transmission pathway using the matrix adapted by Cristobel Zepeda accompanying other expert consultations. The relevant data obtained from published and unpublished sources, together with survey data of field observations, were used to formulate and confirm the risk pathways and their associated risks. The results revealed that the risk of the release of the HPAI virus was medium when exposure was high. Additionally, the consequence would be considered very high with a medium degree of uncertainty for all parameters. Ultimately, the overall risk for transmission was estimated as medium with a medium degree of uncertainty. The findings of this study reveal that there is a significant threat that HPAI virus transmission could occur among poultry and humans and effectively sustain within the environment of the LPMs. Our findings are primarily focused on public health considerations, the hygienic slaughter of poultry and the relevant cleaning and sanitation practices conducted in the LPMs to support evidence‐based decision‐making processes. The findings of the study have the potential to be used to formulate effective risk reduction measures and can be further adapted in low‐resource settings without major infrastructural changes required of the LPMs. All of which would reduce the risk of HPAI virus release and further lessen the degree of exposure and transmission in established LPMs. 相似文献
43.
Eight plant species were subjected to artifical acid rains of pH 2.5, 2.0, 1.5, 1.0 and 0.5 in order to determine the threshold for and symptoms of damage. The plants were Erechtites, Robinia, Pinus, Quercus, Carya, Liriodendron, Acer and Corpus from the Coweeta Hydrologic Laboratory near Franklin, North Carolina Droplets of pH 2.0 produced brown necrotic spots on all species except Pinus while droplets of pH 1.0 produced necroses on leaves of all species examined. The size of necrotic spots increased with increasing acidity. Comparison of these results with the literature suggests that developing leaves are more easily damaged than are the mature leaves used in this study. The volume weighted average rainfall pH for Coweeta is 4.6 with observations ranging from 3.2 to 5.9. Results of this study suggest that a 10-fold increase in acidity from pH 3.2 to 2.2 in a single spring or summer storm could bring damage or death to mature leaves of dominant flowering plants in the Southern Appalachians. 相似文献
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Medina-Torres CE Mason SL Floyd RV Harris PA Mobasheri A 《Veterinary journal (London, England : 1997)》2011,190(2):e54-e59
The aim of this study was to determine if hypoxia and the hypoxia mimetic cobalt chloride regulate the activity of matrix metalloproteinase (MMP)-2 and -9 in cultures of equine hoof keratinocytes. These effects were assessed in primary cultures of laminar keratinocytes using gelatin zymography. Incubation of keratinocytes with cobalt chloride significantly increased the levels of active MMP-2 compared to untreated controls. Hypoxia significantly increased the expression of active MMP-2 and -9 in keratinocyte cultures. This up-regulation was observed after 6h and peaked at 24h. The study findings provide novel evidence of a potential link between hypoxia within the hoof and up-regulation of MMPs which may in turn result in damage to the lamellar basement membrane. 相似文献
46.
Actin Polymerization: An Event Regulated by Tyrosine Phosphorylation During Buffalo Sperm Capacitation
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In the female reproductive tract, the spermatozoa undergo a series of physiological and biochemical changes, prior to gaining the ability to fertilize, that result to capacitation. However, the actin polymerization and protein tyrosine phosphorylation are the two necessary steps for capacitation. In this study, we have demonstrated the actin polymerization and established the correlation between protein tyrosine phosphorylation and actin reorganization during in vitro capacitation in buffalo (Bubalus bubalis) spermatozoa. Indirect immunofluorescence and Western blot techniques were used to detect actin polymerization and tyrosine phosphorylation. The time‐dependent fluorimetric studies revealed that the actin polymerization starts from the tail region and progressed towards the head region of spermatozoa during capacitation. The lysophosphatidyl choline (LPC)‐induced acrosome reaction (AR) stimulated quick actin depolymerization. The inhibitor cytochalasin D (CD) blocked the in vitro capacitation by inhibiting the actin polymerization. In addition, we also performed different inhibitor (Genistein, H‐89, PD9809 and GF‐109) and enhancer (dbcAMP, H2O2 and vanadate) studies on actin tyrosine phosphorylation and actin polymerization. The inhibitors of tyrosine phosphorylation inhibit actin tyrosine phosphorylation and polymerization, whereas enhancers of tyrosine phosphorylation stimulate F‐actin formation and tyrosine phosphorylation. These observations suggest that the tyrosine phosphorylation regulates the actin polymerization, and both are coupled processes during capacitation of buffalo spermatozoa. 相似文献
47.
Hydroacoustic data from the eastern equatorial Pacific reveal low-magnitude seismicity concentrated at the propagating tip of the Galapagos Rise in Hess Deep. The patterns of seismicity and faulting are similar to those observed in the process zone of laboratory-scale propagating tensile cracks. Because the fracture energy required for propagation scales with crack length and process zone size, it follows that ridges can propagate stably in the brittle crust without exceptional resisting forces as proposed by previous models based on linear elastic fracture mechanics. 相似文献
48.
We estimate that to achieve the World Health Organization's tuberculosis control targets, the 22 high-burden countries (HBCs) that collectively account for approximately 80% of the world's tuberculosis cases require about $1 billion per year during the period 2001 to 2005. A further $0.2 billion per year is needed for low and lower-middle income countries outside the 22 HBCs. There is a resource gap of up to around $300 million per year. Substantial progress in tuberculosis control could be achieved with increased investment that is large in the context of existing spending, but small in the wider context of global health expenditure. 相似文献
49.
A field study conducted for two crop cycles of five cropping systems supplied with six nutrient combinations at the Indian Agricultural Research Institute, New Delhi indicated that the cropping systems having a legume increased organic C content over initial level by 0.02?–?0.05%, available N by 3.5?–?14.1?kg ha???1, whereas the rice-wheat cropping system resulted in a reduction in organic C and available N over initial level by 0.05% and 1.5?kg ha???1, respectively after 2 years of study. Rice-potato-mungbean cropping system resulted in a negative balance of available P and rice-clover cropping system had a negative balance of both available P and available K content in soil and thus call for adequate P and K fertilization. Application of P and K helped in building up their content in soil; NPK?+?FYM showed the highest increase in organic C, available N, available P and available K content in soil. These results suggest the inclusion of a legume in a cropping system for maintaining organic C and available N in soil and adequate P and K fertilization for arresting the depletion of available P and K content in soil. Integrated nutrient management is one of the best methods for resilience of soil fertility under rice-wheat cropping system. 相似文献
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