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The Characteristics of Aftershock Activities of Dien Bien Earthquake on 19 February 2001 and Their Relation to the Local Geomorphological, Tectonic Features

Abstract

This article examines in detail the characteristics of Dien Bien earthquake on 19 February 2001 and its aftershocks. On the basis of the temporal development of aftershocks and the spatial distribution of tectonic faults, five aftershock series have been determined. The analysis of spatial distribution and temporal evolution of these five aftershock series has clarified the development in the source zone of Dien Bien earthquake, which is closely related to the active and recent activities of tectonic faults in the area, especially Lai Chau Dien Bien fault. The comparison between characteristics of aftershock activities of Dien Bien earthquake and geomorphological features as well as tectonic activities in the area has indicated that the magnitude of these aftershocks and their temporal evolution (early or late) depend not only on the closer or further distance compared to the mainshock and the active faults that cause them but also on terrain elevation, slope index, lineament density and their positions relative to other tectonic faults in the studied area.

Open access
Characterization of a novel lipase from Pseudomonas aeruginosa

Abstract

Lipases cleaving oils into fatty acids and glycerol are of great interest for the use in increasing the efficiency of fuels. In this work, a novel lipase from Pseudomonas aeruginosa, P. aeruginosa A12, was isolated by ion-exchange and hydrophobic chromatography. The purity of lipase was shown by electrophoresis and its molecular weight was estimated to be ~ 31.6 kDa. The whole amino acid sequence was analyzed by an LC-MS/MS method. Temperature- and pH-dependent optimum of the enzyme compiled 30 °C and 7.5, respectively. The obtained enzyme exhibited 79 % similarity of amino acid sequence to a lipase isolated from the same strain of P. aeruginosa. Thus, the novel lipase was determined to belong to I.1 subfamily of bacterial true lipases. Three dimensional structure of the isolated lipase isoform was modeled based on obtained sequences. Amino acids forming the catalytic domain were shown in the model. Lid domain is suggested to be in the open conformation. These results provide a potential alternative for enzymatic digestion of fuel oils and serve for the development of fundamental knowledge of lipase activity.

Open access
Chromatographic Examinations in the Gas Network Odourised by Tetrahydrothiophene

Abstract

The paper presents the results of the spread of the tetrahydrothiophene (THT) - used as odourant - in the gas network. Such analyses allow quick detection of leaks in networks, systems and devices of gas supply directly to consumers. The main goal of the study was to determine the effectiveness of the use of portable chromatograph and comparing it with a stationary odourant concentration analyser. Based on these studies, an attempt to determine the odouration zone for the selected city have been also taken. For this purpose, three series of measurements were made - in each series 13 points were analysed. Obtained results confirmed the effectiveness of the measurement a concentration of odourant in the gas network using a portable gas chromatograph - difference in relation to the stationary chromatograph ranged from 1.91 to 2.55 %.

Open access
Considerations on the Legal Protection of the Atmosphere

Abstract

Air quality is an issue of general, global interest, which requires the implementation of appropriate environmental policies, taking into account the essential connection between the world economy and the environment. Air is an important natural element of the environment, vital for human life and health, as well as for fauna and flora, and it needs to be protected by all means, including legal methods.

Lately, scientific studies and researches have shown that the chemical structure of the atmosphere is changing for natural or anthropogenic causes, which requires more effective monitoring of the impact of human activity on the atmosphere, doubled by the implementation of radical measures, including legal ones, meant to insure the protection of this environmental element.

The increase in the quantity of polluting gases eliminated into the atmosphere causes global warming, destroying the ozone layer and generating other imbalances in the natural environment.

In these conditions, and since pollution knows no political-administrative borders, being a global phenomenon, there is an absolute need for international cooperation based on conventions and treatises on this topic, or directives from international bodies and organisations, and at a national level, the environmental legislation must aim to protect the air in the troposphere as well as the other elements outside the troposphere, such as the ozone layer, which is part of the stratosphere.

Open access
The Contingency of Soil Microorganisms and the Selected Soil Biotic and Abiotic Parameters Under Different Land-Uses

Abstract

Land use changes are local phenomena with global impact. They have an impact in a cumulative sense on biodiversity or soil degradation. This study aimed to examine the effects of different land-uses (arable land, permanent grasslands, abandoned grasslands, forest land) on the selected biotic and abiotic soil parameters in the Slovak mountain study sites Liptovská Teplička and Tajov. Biotic (microbial community structure, earthworm number and fresh body biomass, arthropod number and fresh body biomass), and abiotic chemical soil parameters (pH, total organic carbon, total nitrogen, nutrients) were measured. According to MALDI-TOF (Matrix Assisted Laser Desorption Ionization-Time of Flight), several bacterial strains were identified. Mutual relations between soil microorganisms and soil biotic and abiotic properties determined by different land uses were analysed. Microbial response expressed as average well-colour development (AWCD) values indicated relations between higher microbial diversity and higher nutrient availability at both study sites. In the comparison of land use types, permanent grasslands (PG) showed the lowest microbial activity in the depth of 0–0.1 m. But in the depth of 0.2-0.3 m in PG of both study sites, the higher microbial activity was recorded compared to the depth of 0-0.1 m. In addition, lower AWCD values in PG were in line with the lower available P and K content but higher earthworm density and biomass.

Open access
A Coupled Insulin and Meal Effect Neuro-Fuzzy Model for The Prediction of Blood Glucose Level in Type 1 Diabetes Mellitus Patients.

Abstract

Diabetes Mellitus is a metabolic disorder that affects the ability of the human body to properly utilize and regulate glucose. It is pervasive world-wide yet tenuous and costly to manage. Diabetes Mellitus is also difficult to model because it is nonlinear, dynamic and laden with mostly patient specific uncertainties. A neuro-fuzzy model for the prediction of blood glucose level in Type 1 diabetic patients using coupled insulin and meal effects is developed. This study establishes that the necessary and sufficient conditions to predict blood glucose level in a Type 1 diabetes mellitus patient are: knowledge of the patient’s insulin effects and meal effects under diverse metabolic scenarios and the transparent coupling of the insulin and meal effects. The neuro-fuzzy models were trained with data collected from a single Type 1 diabetic patient covering a period of two months. Clarke’s Error Grid Analysis (CEGA) of the model shows that 87.5% of the predictions fall into region A, while the remaining 12.5% of the predictions fall into region B within a four (4) hour prediction window. The model reveals significant variation in insulin and glucose responses as the Body Mass Index (BMI) of the patient changes.

Open access
Cytogenetic Abnormalities in Seed Progenies of Pinus Pallasiana D. Don Stands from Technogenic Polluted Lands in the Steppe of Ukraine

Abstract

In this study, we compare the pathological mitosis rates, chromosomal abnormalities and nucleolar organizer activity in Pinus pallasiana D. Don seedlings from natural population in the Crimean Mountains and from the urban plantations in the steppe of Ukraine. On the stages of anaphase and telophase of mitosis, such chromosomal abnormalities as bridges were most often found in the seeds of plantations exposed to air pollutants, whereas lead and agglutination of chromosomes were found in seeds from iron ore dump stands. Our studies have shown that P. pallasiana can be used for genotoxic monitoring of technogenic polluted lands.

Open access
DFT Investigation of Structural and Electronic Properties of Modified PZT

Abstract

Density of states and geometrical structures of modified Lead zirconate titanate are investigated using density functional theory within local density approximation. The electronic properties and bond length variation have been studied in terms of electronic structure and bonding mechanism principles respectively. Hybridization between Ti 3d - O 2p states and ferroelectric distortion have been addressed as a theoretical approach, to rule the improvement of ferroelectric properties of Lead zirconate titanate. The analysis of Ga, Tl modified Lead zirconate titanate were found to diminish the hybridization between Ti 3d - O 2p states, the relaxed behavior lead to the reversal of the known ferroelectric distortion. Y, Ho, Yb and Lu modified Lead zirconate titanate compounds have a tendency to intense the ferroelectric stability, its exhibit higher hybridization between Ti 3d - O 2p states than pure Lead zirconate titanate, also the arrangement of the ions distortions is strongly the same as the more favoured ferroelectric states of Lead zirconate titanate.

Open access
Diethanolamine-Induced Hepatic Steatosis in Mice and Its Amelioration by Curcumin

Abstract

Extensive use of chemicals in personal care products has led to many health issues. Diethanolamine is one of such harmful chemicals containing two highly functional groups alcohol and amine that requires toxicological evaluation and its mitigation. Swiss strain albino mice were used and divided into different control and treated groups. Different doses of DEA (110, 165 and 330 mg/kg body weight/day) were orally administered for 30 days. Biochemical and histopathological assessments were performed at the end of the treatment. Results collectively revealed body weight loss as well as significant increase in absolute and relative liver weight in DEA-treated groups. Biochemical analysis revealed that DEA treatment further promotes significant (P<0.05), dose-dependent increase in lipid and cholesterol contents and also cause decrease in protein and glycogen content. Histopathological assessment confirms vacuole formation due to accumulation of lipid within the liver tissue. Administration of curcumin (10, 20 and 30 mg/kg body weight/day) along with high dose of DEA (330 mg/kg body weight/day) showed improved values of lipid, cholesterol, protein and glycogen contents. It also helped retaining normal histological structure of liver. Observations in all groups and results indicate DEA-treatment causes hepatic steatosis and treatment of curcumin attenuated effect of DEA that is due to its potential antioxidant properties.

Open access
Dynamics of Selected Soil Quality Indicators in Response to Land Use/Cover and Elevation Variations in Wanka Watershed, Northwestern Ethiopian Highlands

Abstract

Soil quality (SQ) dynamics assessment vis-à-vis land use/land cover (LULC) and elevation variations in Ethiopia is desirable as elevation impact on land use is highly pronounced. This study examined SQ indicators dynamics across LULC and elevation variations. For this, surface soil samples (0−20 cm) were collected from the recognized LULC categories of different elevations in Wanka watershed, northwestern Ethiopian highlands. Both disturbed and undisturbed soil samples that were taken from three adjacent LULC (natural forest, grazing and cultivated lands) and elevation (2238–2300, 2400–2600, and 2700–2800) classes analysed for the selected physico-chemical SQ indicators. Two-way ANOVA, Tukey’s multiple comparison test and SQ deterioration index were computed. The impact of LULC and elevation was found significant on key SQ indicators. In cultivated and grazing lands, soil organic matter (SOM) and soil nutrients like total nitrogen declined significantly (p < 0.01). Conversely, bulk density increased significantly (p < 0.01). The divalent basic cations (Ca2+ and Mg2+), cation exchange capacity and pH significantly (p < 0.01) decreased in upper elevation. Synergetic effect of LULC and elevation variations was found significant (p < 0.01) on SOM, total nitrogen, available phosphorus, water content at field capacity and soil particle distribution (silt and clay). Thus, elevation specific land management strategies that improve these SQ indicators need to be emphasized.

Open access