Brassinosteroids protect photosynthetic machinery against the cadmium induced oxidative stress in two tomato cultivars

The present study was conducted with an aim to gain better insight of brassinosteroid generated response on the effects of cadmium on photosynthetic machinery and active oxygen metabolism in two tomato cultivars (K-25 and Sarvodya). These tomato cultivars were subjected to graded cadmium levels in soil (0, 3, 6, 9 or 12 mg kg⁻¹ soil) with their foliage being sprayed with 0 or 10⁻⁸ M of 28-homobrassinolide/24-epibrassinolide (HBL/EBL) at 59 d stage. The results suggested that photosynthetic parameters, leaf water potential and activity of several enzymes (nitrate reductase and carbonic anhydrase) decreased significantly in both the cultivars, to a lesser extent in K-25 than Sarvodya with the increasing levels of cadmium in the soil. However, the activity of antioxidant enzymes and proline content increased in response to metal treatment as well as the application of brassinosteroids (HBL/EBL). Overall, exogenous application of brassinosteroids improved the activity of photosynthetic machinery and that of antioxidant defense system in both the cultivars, and also nullified the damaging effect of metal on these parameters.     

Kinetic of formation for single carbon dioxide and mixed carbon dioxide and tetrahydrofuran hydrates in water and sodium chloride aqueous solution

A laboratory-scale reactor system is built and operated to measure the kinetic of formation for single and mixed carbon dioxide–tetrahydrofuran hydrates. The T-cycle method, which is used to collect the kinetic data, is briefly discussed. For single carbon dioxide hydrate, the induction time decreases with the increase of the initial carbon dioxide pressure up to 2.96 MPa. Beyond this pressure, the induction time is becoming relatively constant with the increase of initial carbon dioxide pressure indicating that the liquid phase is completely supersaturated with carbon dioxide. Experimental results show that the inclusion of tetrahydrofuran reduces the induction time required for hydrate formation. These observations indicate hydrate nucleation process and onset growth are more readily to occur in the presence of tetrahydrofuran. In contrast, the presence of sodium chloride prolongs the induction time due to clustering of water molecules with the ions and the salting-out effects. It is also shown that the degree of subcooling required for hydrate formation is affected by the presence of tetrahydrofuran and sodium chloride in the hydrate forming system. The presence of tetrahydrofuran in the hydrate system significantly reduces the amount of carbon dioxide uptake. The apparent rate constant, k, for those systems are reported.     

The state of indoor air quality in Pakistan—a review

Background and purpose  

In Pakistan, almost 70% of the population lives in rural areas. Ninety-four percent of households in rural areas and 58% in urban areas depend on biomass fuels (wood, dung, and agricultural waste). These solid fuels have poor combustion efficiency. Due to incomplete combustion of the biomass fuels, the resulting smoke contains a range of health-deteriorating substances that, at varying concentrations, can pose a serious threat to human health. Indoor air pollution accounts for 28,000 deaths a year and 40 million cases of acute respiratory illness. It places a significant economic burden on Pakistan with an annual cost of 1% of GDP. Despite the mounting evidence of an association between indoor air pollution and ill health, policy makers have paid little attention to it. This review analyzes the existing information on levels of indoor air pollution in Pakistan and suggests suitable intervention methods.     

Spatial and temporal projected distribution of four crop plants in Egypt

This study focuses on the management of the local agroecosystems in order to adapt planting or sowing practices for the projected climate change scenarios. It is projected that there will be increased air temperature throughout all four seasons in the coming 100 years, from the southern towards the northern parts of Egypt. The objective of this study is to investigate the influence of that increased air temperature on the spatial and temporal distribution of four of the major economic crops in Egypt. The study species are cotton (Gossypium barbadense L., cv. Giza 89), wheat (Triticum aestivum L., cv. Gemiza 9), rice (Oryza stiva L., cv. Sakha 101) and maize (Zea mays L., cv. Hybrid 10). Optimum air temperature allowing maximum growth for each of the study crop cultivars and the current and projected air temperature patterns in the future years were used for projection of the seasonal and crop distribution maps in the years 2005, 2025, 2050, 2075 and 2100. Results showed that sowing dates of a target crop may be managed in order to allow maximum predicted planting area in the same region. The current maximum area suitable for planting the Cotton crop in Egypt (104 thousand Fadden/year; one Fadden = 0.96 hectare or 0.42 acre) showed few variations over the coming hundred years. In this case, the sowing dates should be changed from the hotter months (February to April) to the cooler months (January to February). Alternatively, a great reduction in the area planted by Wheat crop was predicted in the coming 100 years. Despite the early planting, a reduction of about 147 thousand Fadden/year was projected by the year 2075. On the other hand, with earlier sowing dates, the maximum areas that are planted by Rice and Maize may not be greatly affected by the projected increase in air temperature.     

Evidence of hydrocarbon contamination from the Burgan oil field, Kuwait: interpretations from thermal remote sensing data

The paper presents the application of thermal remote sensing for mapping hydrocarbon polluted sites. This has been achieved by mono-window algorithm for land surface temperature (LST) measurements, using multi-date band 6 data of Landsat Thematic Mapper (TM). The emissivity, transmittance and mean atmospheric temperature were used as critical factors to estimate LST. The changes in the surface emissivity due to oil pollution alter the apparent temperature, which was used as a recognition element to map out oil polluted surfaces. The LST contrast was successfully used to map spatial distribution of hydrocarbon pollution in the Burgan Oil field area of Kuwait. The methodology can be positively used to detect waste dumping, oil spills in oceans and ports, besides environmental management of oil pollution at or near the land surface.     

Biochemical characterization of a multiple heavy metal, pesticides and phenol resistant Pseudomonas fluorescens strain

Pseudomonas fluorescens SM1 isolate was found to be resistant to some major water pollutants namely Cd2+, Cr6+, Cu2+, Ni2+, Pb2+, BHC, 2,4-D, mancozeb and phenols up to a concentration four times to the normal levels occurring in the highly pollulated regions. Curing experiment brought about the loss of one or more resistance markers indicating the plasmid born resistance. Plasmid profile of SM1 strain showed the presence of one DNA band of 43.6 kb. This Plasmid was isolated from SM1 strain and introduced into Escherichia coli DH5 alpha with a transformation frequency of 6.7 x 10(-4)transformants/recipient cell. The test SM1 strain was also capable of biotransforming Cr(VI) to Cr(III) which is less toxic compounds. Present studies further indicated that the test SM1 strain was not only resistant to 2,4-D, phenols and catechol but also capable of bioremediating these toxicants quite efficiently. Moreover, studies with inhibitors like sodium azide, 2,4-DNP and chloramphenicol suggested that the major mechanism for the bioremediation of the heavy metals other than Cr6+ would be the biosorption process.     

24-Epibrassinolide protects against the stress generated by salinity and nickel in Brassica juncea

The plants of Brassica juncea (L) were grown in the presence of NaCl and/or NiCl2 and were sprayed with 1muM of 24-epibrassinolide (EBL) at 15 days after sowing (DAS) and were sampled at 30 DAS. The plants exposed to NaCl and/or NiCl2 exhibited a significant decline in growth, the level of pigments and photosynthetic parameters. However, the follow up treatment with EBL detoxified the stress generated by NaCl and/or NiCl2 and significantly improved the above parameters. The NaCl and/or NiCl2 increased electrolyte leakage and lipid peroxidation, and decreased the membrane stability index (MSI) and relative water content. However, the EBL treatment in absence of the stress improved the MSI and relative water content but could not influence electrolyte leakage and lipid peroxidation. The antioxidative enzymes and the level of proline exhibited a significant increase in response to EBL as well as to NaCl and/or NiCl2 stress.     

Indoor Air Quality at Rural and Urban Sites in Pakistan

In the developing world, the vast majority of people rely on solid biomass fuels for cooking and heating which results in poor indoor air quality. The present study determined indoor air quality in some rural and urban areas of Pakistan. Measurements were made of particulate mass (PM10, PM2.5 and PM1), number concentration and bioaerosols in different micro environments. PM10 concentrations of up to 8,555 μg/m³ were observed inside the kitchens where biofuels were used as energy source. Cleaning and smoking was identified as a major source of indoor particulate pollution and concentrations of more than more than 2,000 μg/m³ were recorded in the living room during these activities. Indoor number concentrations in Lahore were typically greater than those observed outdoors in European cites. At a rural site the highest Colony Forming Units (CFUs) were in the 0.5 μm–2 μm size fraction, while at the urban location CFUs were dominant for 2 μm–16 μm. It was observed that CFUs(Colony Forming Units) counts were higher inside living rooms than kitchens. It is important to note that women and children were exposed to extremely high levels of particulates during cooking. Overall, indoor air quality in Pakistan was poor and there is a dire need to take a serious step to combat with it.     

Project risk identification and assessment simultaneously using multi-attribute group decision making technique

The identification and assessment of project risks among potential risks can be considered a multi-attribute group decision making (MAGDM) problem including both quantitative and qualitative criteria. We extend the concept of safety to risk identification and assessment; this is to emphasize that the focus should not only be on the time and cost criteria, but also on the health, safety and environment (HSE) criterion. Conventional approaches to risk identification and risk assessment separately tend to be less effective in dealing with the imprecise of the risk assessment individually. The aim of this paper is to present a new methodology for identifying and assessing risks simultaneously by applying MAGDM technique. This paper includes a new procedure for classifying potential risks which it is named potential risk breakdown structure (PRBS) based on project work breakdown structure (WBS). Nominal group technique (NGT) is utilized for gathering potential risks. Obtained results have been applied in gas refinery plant construction successfully.     

Soil-to-plant transfer of radiocaesium for selected tropical plant species in Bangladesh

Soil-to-plant transfer factors (TF) of radiocaesium (137Cs) were determined under field condition for grassy vegetation grown in Bangladesh at contaminated land in the Atomic Energy Research Establishment (AERE) campus. TF values for rice, grass and grassy/root vegetations grown in the same type of soil were also measured under pot condition. TF values of 137Cs for grassy vegetation (2.4 x 10(-2) -4.2 x 10(-2) with an average of 3.1 x 10(-2) +/-0.005) obtained under field condition were slightly lower than the values for grass and grassy/root vegetations (2.9 x 10(-2) -6.6 x 10(-2) with an average of 4.8 x 10(-2) +/-0.01 for grass and grassy vegetations and 2.3 x 10(-2) -5.6 x 10(-2) with an average of 4.0 x 10(-2) +/-0.009 for root vegetations, respectively) obtained under pot condition. However, TF values (9.0 x 10(-3) -2.6 x 10(-2) with an average of 1.9 x 10(-2) +/-0.004) obtained for rice were about a factor of 4 lower than the values obtained for grass and grassy/root vegetations. When the properties of the AERE soils as input parameters were used in the soil-plant transfer model of Absalom, the estimated TF values (4.5 x 10(-2) -6.7 x 10(-2) with an average of 5.3 x 10(-2) +/-0.006) were consistent with the measured values obtained for grass and grassy vegetations under pot condition, however, the model overestimates the TF values for rice.