22 research outputs found

    Information Bank of Phytoremedial Plants in Arid and Semi-Arid Rangeland Ecosystems

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    Accumulation of heavy elements by human activities in ecosystems and food chains created hazards for human, plants and ecosystems. Among different methods of managing heavy elements in the environment, using phytoremedial plants has emerged as an efficient way to reduce the concentration of heavy metals in soils (Shtangeeva, 2008). This research examines the efficiency of this heavy metal reduction strategy in dry rangeland ecosystems

    On n-absorbing submodules

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    All rings are commutative with identity, and all modules are unital. The purpose of this article is to investigate n-absorbing submodules. For this reason we introduce the concept of n-absorbing submodules generalizing n-absorbing ideals of rings. Let M be an R-module. A proper submodule N of M is called an n-absorbing submodule if whenever a1cdotsanminNa_{1}cdots a_{n}min N for a1,ldots,aninRa_{1},ldots,a_{n}in R and minMmin M, then either a1cdotsanin(N:RM)a_{1}cdots a_{n}in (N :_R M) or there are n1n-1 of aia_{i}\u27s whose product with m is in N. We study the basic properties of n-absorbing submodules and then we study n-absorbing submodules of some classes of modules (e.g. Dedekind modules, Prüfer modules, etc.) over commutative rings

    Factors Affecting Rangeland Utilization by Ranchers in the Golestan Rangelands, Iran

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    In Iran, rangelands produce most of the forage resources for livestock. There are various types of traditional grazing systems for the utilization of rangelands, including the consultative, collective and operational multiplayer systems. In the consultative type, certain people are selected by the ranchers and they determine the utilization method and manage grazing. In the collective system, all ranchers use rangeland in common. In the operational multiplayer system, rangelands are used in common but the ranchers share rangelands by rancher-rancher negotiation. This research was undertaken to investigate the human factors as rancher\u27s effect on rangeland utilization in different systems above mentioned

    Investigation of the Fire Effects on Some Physico-Chemical Characteristics of Soil (Case Study: Miankaleh Rangeland, Iran)

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    Fire is one of the ecological factors that can have positive and negative effects on ecosystem processes. Nevertheless, prescribed burning is considered to be an important tool for grassland management, particularly to manipulate the balance between grasses and shrubs (Scheintaub et al. 2009). In Iran, for example, Khodagholi et al. (2001) in the Samirom rangelands of Isfahan Province suggest that fire reduces the shrubs cover and production and leads to the expansion of grasses. Sharifi and Imani (2006) showed that in the semi-steppe of Khalkhal Province shrub cover decreased in contrast to permanent grasses after fire was applied. However, others report that fire can reduce production and plant diversity due to affects on the range soil properties. This research investigated the effects of fire on some soil physico-chemical characteristics in the Miankaleh rangeland in northern Iran

    Mineral Content in Some Species of Leguminosae in Bandar Torkaman Plain Rangelands, Iran

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    Improving the forage quality and balance of their minerals in rangeland ecosystems is important for rangeland managers to improve livestock productivity (Mohamed et al. 2003; Epstein and Bloom 2005). This research investigated the amount of several minerals; Calcium (Ca), Phosphorus (P), Potassium (K) and Magnesium (Mg), in some important species of Leguminosae including Medicago sativa, Trifolium repens, Trifolium pratense and Lathyrus pratensis, that are grazed by livestock in the Bandar Torkaman plain rangelands in north of Iran

    THE EFFECT OF NANOPARTICLE ZnO ON ENVIRONMENT AND DIFFERENT ORGANIZMS (Review)

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    ABSTRACT: Nanotechnology has noticeably developed with potential effects in every science specially by using nanoscale chemical element. Among nano material ZnO is more attention due to its special properties and its less hazard to environmental impact. ZnO like most of nanoparticles is toxic in organiams, however the toxicity of this nanoparticles can be used for antibacterial, antifungal, antiviral and antialga. To reduce the hazard effect of nanoparticles some manufact or chemical particles such as Nanoscale zero-valent iron are introduce that can be used for environmental remediation of polluted water, soil and sediments. In the present study, the effect of Nanoparticle ZnO on environment and different organisms from virous to fish has been reviewed and the application of nanoscale material in treatment of water are discuss

    The survey of diversity, distribution and abundance of phytoplankton in the southern part of Caspian Sea

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    Since phytoplankton are the base of life and productivity of aquatic ecosystems, sustainable ecological study of the Caspian Sea, particularly the distribution and identification of species composition, density and biomass, seasonal and regional variations in phytoplankton before each study seems necessary. Due to various circumstances physical and chemical rivers leading to the sea, seabed topography in different situation appears to be of primary production in the eastern and western between the Caspian Sea in the season, may be altered.Identifying species and determining the distribution and biomass of the changes and how they are affected by environmental changes and we are environmentally conscious. We also compare the current situation with previous studies, we find that the number and types of plankton biomass have been what it is. During 1389 in spring, summer, autumn and winter, in a study of 8 transects of 40 stations. In each transect from Astara to the Turkmen. 5 stations at depths of 5. 10. 20. 50. 100 m were selected for sampling. The total number of 182 species from seven branches Bacillariophyta, Pyrrophyta, Cyanophyta, Chlorophyta, Euglenophyta, Xantophyta and Chrysophyta phytoplankton were identified. Including 81 species of Bacillariophyta, 33 Cyanophyta, 25 Pyrrophyta, 31Chlorophyta, 9 Euglenophyta, 1 Xantophyta and Chrysophyta had 1 specie. Studies have shown that density and biomass of Bacillariophyta were 228 (± 471) per cubic meter × 106) and 6157 (± 290) mg per cubic meter) respectivity and Pyrrophyta were 28/17( ± 27/14) cubic meter × 106in cubic meters) and 3349 ( ± 336) mg per cubic meter) and Cyanophyta 120/40 (± 123/87 ) per cubic meter × 106 per cubic meter), biomass (55 ± 57mg per cubic meter) were the branches of the dominant phytoplankton. Abundance and biomass in different seasons have been significant differences (p <0.05). Most of Bacillariophyta (61 species) was in Autumn and then in winter (48 species). Dominant species of Bacillariophyta were Pseudonitzschia seriata, Rhizosolenia fragilissima, Stephanodiscos sp. , Melosira varians, Nitzschia acicularis and Cyclotella menenghiniana Pyrrophyta was greatest diversity of branches in summer, autumn and winter (19 species), which includes Exuviaella cordata, Exuviaella marina, Prorocentrum praximum and Prorocentrum scutllum. In the autumn density of Cyanophyta was 285.7(±137.1) cubic meters × 106 and biomass was 95(±54) mg per cubic meter) and 18 species were observed. The dominant species in this category were Oscillatoria sp., Nodularia spumigena and Oscillatoria agardhii. Most species of Chlorophyta branche in autumn and winter and summer median region with the highest density at the density of 26.2% and most of it is Binuclearia lauterbornii. Identified as the branches Euglenophyta were Trachelomonas, Euglena and Phacus that were observed in all seasons. In winter, the highest mean biomass was 9(±0.818) mg per cubic meter and the highest density of in summer was 0.5 (±0.5) in cubic meters ×10^6. In winter the depth of 10 meters and surface of Babolsar, Amir Abad and Anzali, a kind of Chrysophyta and in surface of Tonekabon and Anzali a species of Xantophyta were observed that had negligible density and biomass

    The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

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    Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe
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