scholarly journals Determination of Primary and Secondary Lahar Flow Paths of the Fuego Volcano (Guatemala) Using Morphometric Parameters

2019 ◽  
Vol 11 (6) ◽  
pp. 727 ◽  
Author(s):  
Marcelo Cando-Jácome ◽  
Antonio Martínez-Graña

On 3 June 2018, a strong eruption of the Fuego volcano in Guatemala produced a dense cloud of 10-km-high volcanic ash and destructive pyroclastic flows that caused nearly 200 deaths and huge economic losses in the region. Subsequently, due to heavy rains, destructive secondary lahars were produced, which were not plotted on the hazard maps using the LAHAR Z software. In this work we propose to complement the mapping of this type of lahars using remote-sensing (Differential Interferometry, DINSAR) in Sentinel images 1A and 2A, to locate areas of deformation of the relief on the flanks of the volcano, areas that are possibly origin of these lahars. To determine the trajectory of the lahars, parameters and morphological indices were analyzed with the software System for Automated Geoscientific Analysis (SAGA). The parameters and morphological indices used were the accumulation of flow (FCC), the topographic wetness index (TWI), the length-magnitude factor of the slope (LS). Finally, a slope stability analysis was performed using the Shallow Landslide Susceptibility software (SHALSTAB) based on the Mohr–Coulomb theory and its parameters: internal soil saturation degree and effective precipitation, parameters required to destabilize a hillside. In this case, the application of this complementary methodology provided a more accurate response of the areas destroyed by primary and secondary lahars in the vicinity of the volcano.

2011 ◽  
Vol 35 (1) ◽  
pp. 16-24
Author(s):  
Lazem H. Al-Taie

Back ground: Toxoplasmosis is an important zoonosis that causes economic losses in animal herds due to abortion and stillbirth as well as changes in the reproductive and neural system of susceptible animals . Objective: The aims of the present study is to determination the prevalence of T. gondii in farm animals ( sheep& goat)of both genders and different ages in Sulaimani province by using two serological tests (ELISA and LAT). Methods: Blood samples were collected from farm animals ,142 sheep and 46 goats , of different sexes and ages. Tow different serological tests ,ELISA and LAT for qualitative determination of T. gondii antibody titer in sheep and goats serum samples. Results: The prevalence rate in sheep was 73 (51.7 %) and 82 (57 %) , and 21 (54.6 %) and 25 (54.35 %) in goats ,by ELISA and LAT respectively. The prevalence of toxoplasmosis was highest in age group 7-9 (66.6%) in sheep in compares’ with other age groups. There was no significant differences between both spp.and tow test. Conclusion: Statistical results show no significant differences between both tests (ELISA &LAT) at (P ≥ 0.05).The prevalence of toxoplasmosis was increased proportionally with the age of animals, while gender has no effect on the prevalent rate .


Lab on a Chip ◽  
2019 ◽  
Vol 19 (18) ◽  
pp. 2973-2977 ◽  
Author(s):  
Juhwan Park ◽  
Je-Kyun Park
Keyword(s):  

Integrated microfluidic pumps and valves for fluid delivery and determination of flow paths are operated simultaneously by pushing a button.


2020 ◽  
Author(s):  
Jerom P. M. Aerts ◽  
Steffi Uhlemann-Elmer ◽  
Dirk Eilander ◽  
Philip J. Ward

Abstract. Floods are among the most frequent and damaging natural hazard events in the world. In 2016, economic losses from flooding amounted to $56 bn globally, of which $20 bn occurred in China (Munich Re, 2017). National or regional scale mapping of flood hazard is at present providing an inconsistent and incomplete picture of floods. Over the past decade global flood hazard models have been developed and continuously improved. There is now a significant demand for testing of the global hazard maps generated by these models in order to understand their applicability for international risk reduction strategies and for reinsurance portfolio risk assessments using catastrophe models. We expand on existing methods for comparing global hazard maps and analyse 8 global flood models (GFMs) that represent the current state of the global flood modelling community. We apply our comparison to China as a case study and, for the first time, we include industry models, pluvial flooding, and flood protection standards in the analysis. We find substantial variability between the flood hazard maps in modelled inundated area and exposed GDP across multiple return periods (ranging from 5 to 1500 years) and in expected annual exposed GDP. For example, for the 100 year return period undefended (assuming no flood protection) hazard maps the percentage of total affected GDP of China ranges between 4.4 % and 10.5 % for fluvial floods. For the majority of the GFMs we see only a small increase in inundated area or exposed GDP for high return period undefended hazard maps compared to low return periods, highlighting major limitations in the models’ resolution and their output. The inclusion of industry models which currently model flooding at higher spatial resolution, and which additionally include pluvial flooding, strongly improves the comparison and provides important new benchmarks. Pluvial flooding can increase the expected annual exposed GDP by as much as 1.3 % points. Our study strongly highlights the importance of flood defenses for a realistic risk assessment in countries like China that are characterized by high concentrations of exposure. Even an incomplete (1.74 % of area of China) but locally detailed layer of structural defenses in high exposure areas reduces the expected annual exposed GDP to fluvial and pluvial flooding from 4.1 % to 2.8 %.


2012 ◽  
Vol 51 (No. 5) ◽  
pp. 180-192 ◽  
Author(s):  
J. Hosek ◽  
P. Svastova ◽  
M. Moravkova ◽  
I. Pavlik ◽  
M. Bartos

Mycobacteria cause serious infections in animals and human beings. Huge economic losses on farms are caused by selected species of this wide family. A high risk of transmission of infection from animal to human exists. The knowledge of exact pathogen characteristics is an important factor which can improve quick and adequate healing. Cultivation and determination of phenotype is still the “gold standard”, but has the disadvantage of taking a long time and also low detection limit. Biochemical characterisation of isolates is not exact, and it is expensive. A more popular method used is the amplification of specific loci by polymerase chain reaction (PCR). For this method, the isolation of sufficient amounts of purified DNA is necessary. In this paper the most frequently used method for DNA isolation from live mycobacterial cells, body fluids, tissues, histological samples and forensic materials are outlined. This paper assists only as guide for these methods, so we describe them briefly.


CERNE ◽  
2017 ◽  
Vol 23 (3) ◽  
pp. 387-394 ◽  
Author(s):  
Saeid Shabani ◽  
Moslem Akbarinia

ABSTRACT Forest management needs to evaluate various hazards where may cause economic or other losses to forest owners. The aim of this study is to prepare windthrow hazard maps based on logistic regression and random forest models in Nowshahr Forests, Mazandaran Province, Iran. First of all, 200 windthrow locations were identified from extensive field surveys and some reports. Out these, 140 (70%) locations were randomly selected as training data and the remaining 60 (30%) cases were used for the validation goals. In the next step, 10 predictive variables such as slope degree, slope aspect, altitude, Topographic Position Index (TPI), Topographic Wetness Index (TWI), distance to roads and skid trails, wind effect, soil texture, forest type and stand density were extracted from the spatial database. Subsequently, windthrow hazard maps were produced using logistic regression and RF models, and the results were plotted in ArcGIS. Finally, the area under the curves (AUC) and kappa coefficient were made for performance purposes. The validation of results presented that the area under the curve and kappa have a more accuracy for the random forest (97.5%, and 95%, respectively) than logistic regression (96.667%, and 93.333%, respectively) model. Therefore, this technique has more potentiality to be applied in the evaluation of windthrow phenomenon in forest ecosystems. Additionally, both models indicate that the spatial distribution of windthrow incidence likelihood is highly variable in this region. In general, the mentioned findings can be applied for management of future windthrow in favor of economic benefits and environmental preservation.


2010 ◽  
Vol 5 (3) ◽  
pp. 229-235 ◽  
Author(s):  
Takahisa Mizuyama ◽  
◽  
Shinji Egashira ◽  

Many sediment related disasters have occurred in many areas of the world. The table of sediment related disasters from 1997 to 2006 is shown. It shows strong earthquakes and super hurricanes/typhoons cause large landslides and debris flows. Climate change may trigger larger disasters more frequently in the future. Stratovolcanoes are geologically weak and cause huge landslides and debris avalanches. Active volcanoes release lava flows and pyroclastic flows, which cause serious damages. As an example of a typical sediment disaster, a disaster which occurred in Venezuela, in 1999 is briefly reported. The disaster was caused by unusual heavy rainfall. Many people were killed by many debris flows and shallow landslides. The disaster shows information on hazards such as hazard maps and rainfall is necessary and control structures may reduce damages if they had existed. Proper land-use and hazard education are needed.


2021 ◽  
Vol 90 (4) ◽  
pp. 375-381
Author(s):  
Jaroslav Filípek ◽  
Romana Kadek ◽  
Josef Illek

The study deals with the influence of haemolysis on the results of vitamin E determination in plasma (serum) in cattle. Although nowadays specific High Performance Liquid Chromatography (HPLC) techniques are used almost exclusively for the determination of vitamin E, this indicator is also influenced by haemolysis. This occurs in the pre-analytical phase due to the fact that iron contained in haemoglobin is able to catalyze peroxidation reactions. Subsequently, changes occur mainly in polyunsaturated fatty acids in the lipoprotein components of serum/plasma. The vitamin E present inhibits this process, as a result of which its concentration is reduced. The experiment was performed by preparing model samples with a defined degree of haemolysis by adding haemolysate to the centrifuged plasma in the range of ca 0–12 g/l, i.e. mild to severe haemolysis. After 4 h of incubation at room temperature, the vitamin E concentration was determined by the HPLC method. Haemolysis was found to reduce the test result; mild one (approximately up to 2 g/l) non-significantly, medium and severe haemolysis by up to tens of percent, which warrants repeated sampling. False reductions in results will not endanger the patient’s health, but economic losses may occur due to unnecessary check-ups and increased vitamin E supplementation.


2019 ◽  
Vol 13 (2) ◽  
pp. 19-23
Author(s):  
Masoumeh Mahmoodi Maymand ◽  
◽  
Mansooreh Mazaheri ◽  
Mahboobeh Talebi Mehrdar ◽  
◽  
...  

Background: Mycotoxins are the secondary metabolites of molds and have adverse effects on humans, animals, and crops, resulting in illnesses and economic losses. Aflatoxin M1 (AFM1) is a hepatocarcinogen found in the milk from animals that have consumed feeds contaminated with aflatoxin B1 (AFB1). Milk is a highly nutritious food and is a source of necessary macro- and micro-nutrients for the growth, development and maintenance of human health. Methods: The presence of AFM1 was investigated in 70 samples of imported pasteurized and powdered milk products available to the Iranian consumers. The level of AFM1 was determined by HPLC method equipped with immunoaffinity cleanup. Results: The results showed that 32% of the analyzed samples were positive for AFM1 at 0.05-3.31 μg/kg. Also, 16% of analyzed samples were positive for AFM1at concentrations higher than the limit permitted by the Iranian standards. Conclusion: The detection of AFM1 contamination in the analyzed samples indicates the importance of the health of animal feeds. Thus, monitoring the imported feed materials, especially those arriving at Iranian borders is crucial in the prevention of AFM1 and AFB1 contaminations spreading across the domestic market.


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