Vulnerability Of Different Areas Research Articles

Drought vulnerability assessment: Solution for risk alleviation and drought management among Iranian farmers

Drought is a natural disaster that can influence all aspects of human life with its extensive and long-term implications. Rural communities are more drought-susceptible due to their more closeness to nature and agriculture-based economy. Careful assessment of the drought vulnerability of different areas is a prerequisite for drought management as risk management has replaced crisis management to enable farmers to cope with drought effects. The present study aimed to assess the drought vulnerability of wheat farmers in southeastern Iran. The main data collection instrument was a questionnaire designed based on Me-Bar and Valdez’s (2005) study, to which new parameters were added for a more accurate assessment of vulnerability. Using Krejcie and Morgan Table, the sample size was determined to be 395 wheat farmers selected from those living in southeastern Iran with different degrees of drought severity (severe, extremely severe, and critical). The results indicated that farmers were highly vulnerable to drought and strongly affected by economic, socio-cultural, psychological, technical-environmental, and infrastructural damages. In addition, the results revealed that farmers in Sirjan and Rudbar-e Jonubi counties were the most vulnerable. The general results concerning the vulnerability in southeastern Iran show that further drought aggravation increases the farmers' vulnerability because of higher vulnerability levels in regions with more critical conditions. In general, the results can provide new insights into drought management for policymakers.

GIS modeling of seismic vulnerability of residential fabrics considering geotechnical, structural, social and physical distance indicators in Tehran using multi-criteria decision-making techniques

Abstract. The main issue in determining seismic vulnerability is having a comprehensive view of all probable damages related to earthquake occurrence. Therefore, taking into account factors such as peak ground acceleration at the time of earthquake occurrence, the type of structures, population distribution among different age groups, level of education and the physical distance to hospitals (or medical care centers) and categorizing them into four indicators of geotechnical, structural, social and physical distance to needed facilities and from dangerous ones will provide us with a better and more exact outcome. To this end, this paper uses the analytic hierarchy process to study the importance of criteria or alternatives and uses the geographical information system to study the vulnerability of Tehran to an earthquake. This study focuses on the fact that Tehran is surrounded by three active and major faults: Mosha, North Tehran and Rey. In order to comprehensively determine the vulnerability, three scenarios are developed. In each scenario, seismic vulnerability of different areas in Tehran is analyzed and classified into four levels: high, medium, low and safe. The results show that, regarding seismic vulnerability, the faults of Mosha, North Tehran and Rey make, respectively, 6, 16 and 10% of Tehran highly vulnerable, while 34, 14 and 27% is safe.

Metabolic adaptation and neuroprotection differ in the retina and choroid in a piglet model of acute postnatal hypoxia.

Hypoxic-ischemic insults to the neonatal brain may cause neurodevelopmental disorders. Vulnerability of different areas of the neural tissue to hypoxic-ischemic stress might be explained by either heterogeneous sensitivity to oxygen or neuroprotective capability. Our understanding of regional heterogeneity is still incomplete in terms of metabolic reconfiguration and/or activation of neuroprotective mechanisms. We studied, by western blotting, reverse-transcriptase PCR, and tandem mass spectrometry, the response of retina and choroid at protein, gene, and metabolic levels during hypoxia in a piglet model of acute postnatal hypoxia. We evidenced a metabolic shift towards glycolysis in choroid after hypoxia while retina experienced a dramatic energy stress with decreased mitochondrial metabolites. Hypoxia-inducible transcription factor-1α (HIF-1α) was not stabilized in retina during hypoxia, supported by a deficient signaling from v-akt murine thymoma viral oncogene (AKT) and ERK1/2, and unchanged glutathione redox status. In retina, but not in choroid, phosphorylation of p65 (NF-κB) and increased transcription of target genes may have a major role during hypoxic stress. We showed that the retina engages a distinct pattern of signaling and transcriptional events than observed in the choroid. Retina and choroid may reflect regional sensitivity to hypoxia. While prolonged and intense hypoxia may jeopardize retinal cell survival, choroid sets up a different pattern of response, which promotes adaptation to these adverse conditions.

Differential neuronal vulnerability varies according to specific cardiopulmonary bypass insult in a porcine survival model

We investigated whether the degree of vulnerability of different areas in the developing brain varies according to the specific mechanism of the insults caused by cardiopulmonary bypass. A meta-analysis of 2 experimental studies (n = 80) was conducted. The end points of the otherwise identical studies were tissue oxygen index in the first experiment, whereas cerebral microvessel vasoconstriction and inflammatory response of endothelial cells were directly visualized in the second study. We assigned ultra-low flow bypass at 25 °C for 60 minutes as control; circulatory arrest at 25 °C for 60 minutes as ischemic stress under circulatory arrest (ischemia-CA); and ultra-low flow bypass at 34 °C for 60 minutes as the stress under ultra-low flow bypass (ischemia-ULF). Histologic neuronal damage was the primary outcome. Secondary measures included neurologic recovery. Vasoconstriction after ischemia and inflammation after bypass were independent predictors of severe histologic damage. The caudate nucleus was significantly vulnerable to ischemia-CA and was significantly influenced by vasoconstriction. In contrast, the hippocampus was significantly vulnerable to ischemia-ULF. The different forms of ischemic insults did not influence Purkinje cells, whereas Purkinje damage significantly correlated with inflammation. Tissue oxygen index had the ability to differentiate accurately regional damage. Neurologic recovery under ischemia-CA was significantly worse compared with ischemia-ULF. Neurologic recovery correlated with neuronal damage in the caudate nucleus, but it did not correlate with damage in the hippocampus. Neuronal vulnerability in different areas of the developing brain varies according to mechanisms of bypass-induced ischemic stress. Certain regional damage may not be apparent in assessing acute neurologic recovery.

Global ischemia-induced modifications in the expression of AMPA receptors and inflammation in rat brain

Alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptors (AMPAR) and inflammatory processes have been related to ischemia-induced damage, but there are few studies addressing their response in different brain areas. Here we compare AMPAR expression after ischemia in several brain areas (hippocampus, cerebral cortex and caudate-putamen) in an attempt to correlate it with their different vulnerabilities. We found outstanding decreases in GluR1 and GluR2 mRNA levels after global ischemia and 48 h reperfusion (I/R) in all the areas studied, however, protein levels maintained in some areas such as CA3, suggesting different post-transcriptional control in different areas of the brain. To characterize the inflammatory response in these areas, we measured the mRNA levels of CD11b/CD18 membrane integrin (a reactive microglia marker), which showed an important but similar up-regulation in all brain areas studied, which was confirmed by immunohistochemistry. We conclude that the down-regulation of AMPAR gene expression following I/R does not explain differences in the vulnerability of different areas. Additionally, our data indicate that the level of inflammation is independent of the vulnerability of the different brain areas and does not explain differences in the AMPAR expression observed in the brain areas studied.