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Air-Borne Particle Size Distribution of Wood Dust Emitted during Small Scale Forestry Operations
No full textPractices such as tree felling, pruning, logging and chipping wood can produce significant amount of wood particles that can be inhaled by agricultural and forestry workers, triggering an important risk to the health of workers. Especially finest fractions of dust, less than 4 µm in diameter (the respirable fraction) may cause respiratory and dermal diseases, until to the risk of developing nose and sinus adenocancer. The aim of this work was to assess the particle size distribution of wood dust produced during chainsaw operations. In two separate trials (July and December), wood logs of three different species (Eucalyptus sp., Pinus radiata and Quercus cerris) were employed in cutting tests. Two chainsaws, one electric powered by batteries and one endothermic, were employed. To characterize the particle size distribution, samplings were carried out with a dust particle counter placed in the area surrounding the tests’ site. Results showed that the dust was characterized by a major fraction of fine particles around 0.3 µm (72% of the particles from 0.3 to 10 µm). The chainsaw with endothermic engine produced more fine dust of the electric one. Obtained amounts of inhalable wood dust were very variable in values, however attention should be paid to the exposure to wood dust considering potential risks, especially in case of long times of exposure
Choice of Remediation Technology for a Contaminated Soil by 1,2-Dichloroethane (DCA)
No full textIn Mexico, there are 635 sites contaminated by hazardous waste, due to the fact that a few years ago there was no legislation to support and guarantee environmental protection. This led to decades of contamination of soils and bodies of water. In the following case study, landfills were identified where 1,2-dichloroethane was stored, generating contaminated soil in this location, even affecting subway water bodies. The aim of this work is to identify the technologies for the remediation of contaminated soils, taking into account the affected site, the characteristics of the residue, costs and time, in order to determine the most effective and ideal technology. The Federal Remediation Technologies Roundtable (FRTR) will be considered as the counterpart for the selection of treatment technologies, published by the Remediation Bureau. The best technology for site remediation is "Soil Vapor Extraction", being the most ideal and efficient in terms of time and cost, and generating a high impact remediation outcome. The counterpart (FRTR) is considered to be a support tool that provides the most appropriate technologies for the remediation of a contaminated site
Biologically Structured Water-A Review (Part 2): Redox Biology, Plant Resilience, SW Drinking Water Types, BSW Water and Aging, BSW Water and Immunity
Get PDFA review was conducted between redox biology and BSW water to link their interactions with cell bioenergetics. The exchange of electrons and protons from energized BSW water significantly contributes to recycling energy biomolecules during aerobic respiration. Plant resilience to biotic and abiotic stressors is also significantly improved by maintaining adequate levels of BSW water. The physicochemical properties of SW water are readily measured and are associated with improved human health. Natural healing water and SW water products have similar physicochemical properties. Medical literature shows a direct association between dehydration and age-related diseases. Drinking SW water enhances rehydration rates and increases intracellular water content. Research has also suggested that drinking SW water has a positive effect on certain neurological diseases and cancer types. Finally, drinking SW water improves the immunity system in humans
District-Level Seasonal Rainfall Characteristics over Andhra Pradesh and its Global Teleconnections in Changing Climate
Get PDFInvestigating the trends and changes in rainfall over vulnerable regions is of huge importance in this global warming era. The present study intensively investigates the rainfall over the Indian state, Andhra Pradesh (AP), and its 13 districts using a high-resolution (0.25°×0.25°) gridded rainfall analysis dataset from India Meteorological Department (IMD) for the study period of 118 years (1901-2018). For this, normality, homogeneity, persistence, and change-point tests are performed and changes in the district-level rainfall in the present global warming period (1991-2018) as compared to the pre-global warming period (1901-1990) is also analyzed.
The results suggest that the long-term average annual rainfall over AP is 882 mm and most of the rainfall is contributed by the monsoon (55.7%) and the post-monsoon rainfall (32.8%). The coefficient of variation is low (high) during monsoon (winter). The coastal region receives more rainfall than the inland districts. The post-monsoon rainfall over AP is more consistent than in other seasons, and the persistence is only during the southwest monsoon season. The southwest monsoon and post-monsoon rainfall have increased (by about 10%) over most of the districts in the recent period. The Nino3.4 region SST (South Oscillation Index; SOI) has a significant negative (positive) relationship with southwest summer monsoon rainfall in most of the districts. The relationship of Nino 3.4 SST and DMI is strikingly similar for post-monsoon and has significantly weakened in recent decades. This study is useful for proper planning and mitigation measures for the agricultural and water resources sector at the district level over AP in this global warming era
A Mini Review on Treatment of Wastewater with Membrane Technology
No full textWastewater treatment is a continuous environmental problem, which troubles human activities. Numerous efforts have been made over the years to develop newly efficient technologies, including traditional filtration, coagulation-flocculation, and biological treatment systems. Among which, membrane technology is proven to be a significant one. Membranes technology is divided into four categories based on pore size. The four types of membrane technology including micro-filtration, ultra-filtration, nano-filtration, and reverse osmosis. This paper focus on the introduction, advantages, disadvantages and protection of these four membrane processes
Influence of Microstructure on the Dynamic Behaviour of Polyurethane Foam with Various Densities
Get PDFPolyurethane foam is reinforced with varying proportions of metal loads and other components to increase shock absorption and mechanical impact. The main objective is to develop high-performance polymeric materials based on polyurethane foam developed with different compositions and specific densities. We monitor the growth distances and temperatures of the polyurethane foam in time to reach the optimum formulations. We conduct static compression tests and investigate the effect of drop weight on the deformation of polyurethane foam structures by dropping a weight from a specified height. Dynamic collisions cause deformations of the polyurethane foam structure. After investigating the low weight, we found that polyurethane foams have a good absorption coefficient at certain frequencies. Dynamic stress-strain response curves are used to characterize different stress rates. High-stress levels and similar strains indicate a high resistance to shock. We follow the evolution of microstructure structures by scanning electron microscopy (SEM) to observe deformation and fracture behavior with reversibility and recovery
The Sun and the Troposphere Control the Earth’s Temperature
Get PDFThe basis for this study is the flow of energy from the Troposphere to space and the role that water vapor and carbon dioxide (CO2) play in affecting the flow. Then, it analyzes the radiation profiles and compares them to the ratio of water molecules to CO2 molecules. Examining the radiation profiles of water vapor and CO2 showed the overlap made it virtually impossible to separate the warming effects. Calculating the ratio of water vapor molecules to CO2 molecules by proven physics and chemistry is accurate for separating the individual warming effects. The results of a quantitative examination show water vapor has 1,000 to 7,000 times more impact on the Earth\u27s temperature than CO2. The warming effect of CO2 versus concentration is linear. In contrast, the warming effect of water vapor versus concentration is curved. The lowest level of the atmosphere, the Troposphere, has most of the air mass and water vapor and exercises control over the Earth\u27s temperature. Energy leaving the Troposphere flows virtually unhindered to space. The Sun is Earth\u27s primary energy source, and its natural variations control its temperature
Histological Assessment of Selenium Protective Effect Against Diclofenac Sodium-Induced Nephrotoxicity in Rats
Get PDFDrug-induced nephrotoxicity is a matter of global significance, with widespread implications for human health. Non-steroidal anti-inflammatory drugs (NSAIDs), such as Diclofenac Sodium, are widely used but have been associated with numerous adverse effects, including those on the gastrointestinal tract, liver, and kidney. Selenium, an essential element in mammalian biology, has demonstrated antioxidant properties that enable it to antagonize the effects of free radicals. The present study aimed to investigate the potential protective effect of Selenium against Diclofenac Sodium-induced nephrotoxicity in rats. The study sample consisted of 32 male albino Wistar rats and was randomly divided into 4 groups: Control group, Diclofenac group (Dic group) (administered at a dose of 50 mg/kg I.M., for 3 days), Selenium group (Se group) (administered at a dose of 1 mg/kg I.P., for 8 days), and Diclofenac plus Selenium group (Dic + Se group). Rats were sacrificed on the 9th day. The results were analyzed with a significance level of p<0.05. The findings revealed significant tubular and glomerular injuries in the Diclofenac group compared to the control group. However, there was no statistically significant improvement observed in the Dic + Se group. In conclusion, the results of this study suggest that Selenium affords partial protection against Diclofenac Sodium-induced nephrotoxicity, but it is not sufficient to provide complete protection
Acid Suppressant Activity of Feed Dietary Supplements for Dogs: An In vitro Study
Get PDFGastritis is a common finding in pets and acid suppression plays an important role in its management. Acid suppression is the most important component in the treatment of gastritis and prevention of its complications. There are many drugs commonly used in veterinary medicine but the use of natural feed supplements is increasing. The aim of this in vitro study is the comparison of four supplements based on a combination of antacid salts and natural products at two pH conditions (pH 2 and 4.5) and at five time points. In addition, we wanted to confirm the formation of the gel during the test. All the products demonstrated acid suppression activity. In particular, product A showed the best performance. All the products except one (product B) formed gel after five minutes from the beginning of the experiment confirming their protective activity. Based on this preliminary results, the product A resulted to be the most promising antacid and potentially gastric protective product compared to others
Spermatogenic Inhibition Properties of a Phenolic Phytoestrogen Isolated from Momordica charantia (Bitter Guard) Seeds
No full textMechanisms and potencies of phytoestrogens are not completely clarified and they may be considered potential endocrine disruptors, and therefore caution should be exercised while taking them. Eating very high levels of some phytoestrogens may pose some health risks. Reproductive problems have been documented in laboratory animals, farm animals and wildlife that ate very high (up to 100% of their diet) amounts of phytoestrogen-rich plants. Sheep consuming large amounts of clover showed infertility and reproductive disorders. Cheetahs in captivity also had reduced fertility rates when consuming a feline diet composed of a soybean product, which was reversed when it was removed from the diet. Toxicities associated with herbal medicines that include phytoestrogens have also been reported in the literature.
Phenolphthalein a phenolic phytoestrogen has been isolated from the crude ethanol extract of Momordica charantia Linn. seeds. After preparative HPLC whitish amorphous compound was obtained. Its structural elucidation using IR, NMR and Mass spectral data revealed that the molecule isolated from the ethanol extract of M. charantia seeds was surprisingly, phenolphthalein. In order to clarify testicular influence of ethanol extract, fractions and isolated phenolphthalein were treated for sixty days to adult male albino rats. All the treated groups showed statistically significant reduction in testis weight. On histological examinations of testis showed spermatogenic inhibition effect, as the number of spermatogonia, spermatocytes, spermatids and spermatozoa were significantly decreased