63 research outputs found
Behavior and Impact of Zirconium in the Soil–Plant System: Plant Uptake and Phytotoxicity
Because of the large number of sites they pollute, toxic metals that contaminate terrestrial ecosystems are increasingly of environmental and sanitary concern (Uzu et al. 2010, 2011; Shahid et al. 2011a, b, 2012a). Among such metals is zirconium (Zr), which has the atomic number 40 and is a transition metal that resembles titanium in physical and chemical properties (Zaccone et al. 2008). Zr is widely used in many chemical industry processes and in nuclear reactors (Sandoval et al. 2011; Kamal et al. 2011), owing to its useful properties like hardness, corrosion-resistance and permeable to neutrons (Mushtaq 2012). Hence, the recent increased use of Zr by industry, and the occurrence of the Chernobyl and Fukashima catastrophe have enhanced environmental levels in soil and waters (Yirchenko and Agapkina 1993; Mosulishvili et al. 1994 ; Kruglov et al. 1996)
Hsp70 Genotypes and Heat Tolerance of Commercial and Native Chickens Reared in Hot and Humid Conditions
Genetic characterization of Bhutanese native chickens based on an analysis of Red Junglefowl (Gallus gallus gallus and Gallus gallus spadecieus), domestic Southeast Asian and commercial chicken lines (Gallus gallus domesticus)
Systematic Review of Potential Health Risks Posed by Pharmaceutical, Occupational and Consumer Exposures to Metallic and Nanoscale Aluminum, Aluminum Oxides, Aluminum Hydroxide and Its Soluble Salts
Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007).
Challenges encountered in carrying out the present review reflected the experimental use of different physical and chemical Al forms, different routes of administration, and different target organs in relation to the magnitude, frequency, and duration of exposure. Wide variations in diet can result in Al intakes that are often higher than the World Health Organization provisional tolerable weekly intake (PTWI), which is based on studies with Al citrate. Comparing daily dietary Al exposures on the basis of “total Al”assumes that gastrointestinal bioavailability for all dietary Al forms is equivalent to that for Al citrate, an approach that requires validation. Current occupational exposure limits (OELs) for identical Al substances vary as much as 15-fold.
The toxicity of different Al forms depends in large measure on their physical behavior and relative solubility in water. The toxicity of soluble Al forms depends upon the delivered dose of Al+ 3 to target tissues. Trivalent Al reacts with water to produce bidentate superoxide coordination spheres [Al(O2)(H2O4)+ 2 and Al(H2O)6 + 3] that after complexation with O2•−, generate Al superoxides [Al(O2•)](H2O5)]+ 2. Semireduced AlO2• radicals deplete mitochondrial Fe and promote generation of H2O2, O2 • − and OH•. Thus, it is the Al+ 3-induced formation of oxygen radicals that accounts for the oxidative damage that leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates.
Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer\u27s disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants.
The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances
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Not AvailablePresent investigation was undertaken to characterize the exon 2 to 3 of major histocompatibility complex (MHC) class I genes in buffaloes (BuLA-A) of Murrah, Mehsana and Bhadawari breeds using Polymearse chain reaction-restriction length fragment polymorphism (PCR-RFLP). Two primers corresponding to the region of exon 2 intron 2 and exon 3 of BoLA-A were used to amplify the fragment of 714 bp. The PCR-RFLP patterns with respect to DdeI, TaqI, and HinfI restriction enzymes produced distinct polymorphic patterns in all the breeds. Two new patterns with the fragment sizes as 614, 60, 39 bp and 417, 187, 78, 21, 12 bp with DdeI digestion and 608, 97, 9 bp and 609, 106 bp with TaqI digestion were observed. The selected genotypes were cloned and sequenced to find out any change in nucleotides or amino acids with respect to the Holstein Friesian sequence available in the NCBI GenBank. The sequencing results showed that the exon 2- exon 3 products varied from 713 to 715 bp in buffaloes. Polymorphism in exon 2 occurred mostly due to changes of nucleotides at the positions from 62 to 72, 121 to170 and 184 to 237. The exon 3 initiated at 468 position of nucleotide after intron 2, which had purine rich region conserve sequence CGGGTCA. The phylogenetic tree predicted changes of higher degree in nucleotides as well as amino acids of exon 2- exon 3 and the nucleotide dissimilarity ranged from 3.0 to 14.7%. The results of the present study revealed that the exon 2 to 3 was found polymorphic in the buffaloes.Not Availabl
Exceptional activity of mesoporous beta-MnO2 in the catalytic thermal sensitization of ammonium perchlorate
Mesoporous beta-MnO2 has been prepared, characterized and demonstrated to possess excellent catalytic activity in the thermal decomposition of ammonium perchlorate. The observed unprecedentedly low decomposition temperatures, fast reaction rates and enhanced heat releases in the catalysed formulations make mesoporous beta-MnO2 promising as a high-performing ballistic modifier in AP-based composite solid rocket propellants
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Not AvailableDroughts are recognized as an environmental disaster and have attracted the attention of environmentalists, ecologists, hydrologists, meteorologists, geologists and agricultural scientists. Successful water management to cope with water scarcity requires the understanding of respective governing processes and causes. Based on different approaches, drought is classified in four classes, meteorological, hydrological, agricultural and socioeconomic drought. Various drought coping mechanisms of cultivating drought tolerant dual purpose crops, mixed cropping, farming system, drought hardy millets, sesame, livestock rearing, storing of grains and fodder during normal or excessive rainfall years are already practiced in our country. In a mixed system, some component will give some return without a complete collapsing of whole crop. Thus, these mitigations strategies may be benificial for policy planning and sustainable crop production.Not Availabl
Probability analysis for consecutive-day maximum rainfall for Tiruchirapalli City (south India, Asia)
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Not AvailableThe impacts of the resource conservation practices can be evaluated in short-term through carbon management index (CMI) that conceptualizes the carbon lability and soil aggregation. To test this hypothesis, we investigated the labile organic carbon (LOC) pool and CMI in relation to runoff, soil loss and maize-wheat system productivity on 2% sloping crop lands of Indian Himalayan region in a study (2009–2014) where different nutrient management practices were adopted. Results showed that all integrated nutrient management (INM) practices (mineral) fertilizers with different organic sources like farmyard manure (FYM), vermi-compost (VC), green manure (GM) and poultry manure (PM) enhanced soil aggregation compared with only mineral fertilization (NPK). Among all the treatments, the highest water-stable macroaggregates ( + 25%) in the 0–5 cm soil layer were recorded in 50% NPK + 50% FYM (7.5 t ha−1) treatment. Aggregate size of >2000, 250–2000, 53–250 and 2000 to <53 µm. Plots with fertilization of 50% NPK + 50% GM (1.8 t ha−1) had significantly higher Walkley-Black carbon (WBC), total soil organic C (TOC), LOC, macroaggregate-associated C concentrations, and soil aggregation than other treatments. In the NPK + FYM treatment, LOC was ∼16% significantly higher in topsoil than the sub-surface soil. CMI varied from ∼17–48% to 15–41% among the nutrient management practices in the 0–5 and 5–15 cm soil layers, respectively. Significant positive correlation was found between CMI with maize yield (r = 0.944; n = 28; p = 0.008), wheat yield (r = 0.942; n = 28; p = 0.005), and negative correlation with runoff (r = −0.818; n = 28; p = 0.042) and soil loss (r = −0.847; n = 28; p = 0.045). FYM, GM, VC and PM with mineral fertilization decreased soil degradation compared to only mineral fertilization and unfertilized control plots, and FYM and GM sources were the best among all the organic sources. The highest wheat equivalent yield (WEY) was recorded with 50% NPK + 50% FYM (∼6.0 t ha−1) while similar WEY was recorded in rest of 50% organic sources. Relationships revealed that the single value CMI can be used for the assessment of soil degradation in the sloping crop lands.Not Availabl
An outbreak of hepatitis E virus infection caused by genotype 1 in an urban setting in eastern India: a probe into risk factors for transmission
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