Vehicle pollution toxicity induced changes in physiology,defence system and biochemical characteristics of Calotropis procera L.

The present study aims to examine the physiological, biochemical and defence system responses of Calotropis procera to vehicle exhaust pollution. We selected various sample sites along two major roads in the Punjab province of Pakistan, i.e. Faisalabad to Sargodha road (FSR) and Pindi Bhattian to Lillah motorway (M-2). Traffic density at all sites and plant responses (i.e. chlorophyll a, chlorophyll b, total chlorophyll and carotenoid contents, transpiration rate, stomatal conductance, photosynthetic rate, sub-stomatal CO₂ concentration, water use efficiency, total free amino acids, total soluble proteins and total antioxidant activity) were measured. Levels of carbon (C) and nitrogen (N) and four metals of most possible concern – i.e. lead (Pb), zinc (Zn), cadmium (Cd) and nickel (Ni) – were also examined in all samples. We found their considerable deposition in all the samples along roads. Inhibitory effects of roadside pollutants were noted for photosynthetic pigments, stomatal conductance, transpiration rate, photosynthetic rate and total soluble proteins, whereas stimulatory effects were noted for sub-stomatal CO₂ concentration, free amino acids and total antioxidant activity. The stimulation of antioxidant enzymes activity revealed stress and mitigation of reactive oxygen species. The present study clearly signifies that C. procera has great potential to endure the stress caused by roadside pollutants.     

Mixing dynamics of turbidity currents interacting with complex seafloor topography

Direct Numerical Simulations are employed to investigate the mixing dynamics of turbidity currents interacting with seamounts of various heights. The mixing properties are found to be governed by the competing effects of turbulence amplification and enhanced dissipation due to the three-dimensional topography. In addition, particle settling is seen to play an important role as well, as it affects the local density stratification, and hence the stability, of the current. The interplay of these different mechanisms results in the non-monotonic dependence of the mixing behavior on the height of the seamount. Regions of dilute lock fluid concentration generally mix more intensely as a result of the seafloor topography, while concentrated lock fluid remains relatively unaffected. For long times, the strongest mixing occurs for intermediate bump heights. Particle settling is seen to cause turbidity currents to mix more intensely with the ambient than gravity currents.     

Fly ash leachate induces oxidative stress in freshwater fish Channa punctata (Bloch)

Oxidative stress inducing potential of fly ash leachate (FAL) was studied in a freshwater fish, Channa punctata (Bloch). Fish were exposed to fly ash leachate for 24 h and lipid peroxidation (LPO) was studied as a marker of oxidative stress. Catalase (CAT), glutathione S-transferase (GST) activities and levels of reduced glutathione (GSH) were also estimated in the exposed fish. FAL (1 ml/l) induced LPO in all the organs and most prominent response was in the gill. It also caused induction of enzymes and glutathione. Liver showed highest level of induction of enzyme activities. The results of this study demonstrate that fly ash constituents have potential to induce oxidative stress in fish and gills are the most vulnerable organs. It is also suggested that in case of exposure to FAL, along with LPO antioxidant defense is also activated to counteract the reactive oxygen species (ROS) at least partly in the initial stages of exposure.     

Characterization of Environmentally Friendly Polymers by Inverse Gas Chromatography: I Amylopectin

Amylopectin, as a potato starch based polymer, with a molecular weight of six million gram/mol was characterized using the Inverse Gas Chromatography Method (IGC). DSC method was also used to measure the glass and melting temperatures. Both DSC and IGC agreed well on a T_g of 105°C and T_m of 160–166°C. Nineteen solutes (solvents) were injected onto a chromatographic column containing amylopectin. These solutes revealed the interaction of alkanes with AP, and the wettability and water intake of AP. Alkanes showed exothermic values of interaction parameters which were increased as the temperature increased and as the number of carbons in the alkane series decreased. Retention diagrams of these solutes in a temperature range of 80–200°C revealed two zones, crystalline and amorphous. T_g and T_m were measured using these zones which complimented the DSC values. The two zones were used to calculate the degree of crystallinity below the melting temperature which ranged from 85% at 104°C to 0% at 161°C. The dispersive component of the surface energy of amylopectin was measured using alkanes which ranged from 25.35 mJ/m² at 80°C to 8.47 mJ/m² at 200°C. This is attributed to the weak crystalline surface of AP at 80°C and when the surface melted at 160°C the surface energy decreased due to the thermal expansion of the surface.     

Ozonation of Procaine Penicillin G formulation effluent Part I: Process optimization and kinetics

Ozonation characteristics of synthetic Procaine Penicillin G (PPG) formulation effluent were investigated in a semi-batch ozone reactor at different pH (3, 7 and 12), ozone feed rates (600-2600 mg h-1) and COD values (200-600 mg l-1). Ozonation of aqueous PPG effluent resulted in 37 (82)% COD removal after 60 (120) min ozonation when the reaction pH was kept constant at pH=7.900 mg l-1 (corresponding to 50% of the total introduced) ozone was absorbed during a reaction period of 1 h. The effects of increasing the applied ozone dose and the initial COD on the COD abatement rates of PPG effluent were also studied. Results have indicated that increasing the ozone dose and decreasing the COD content both have positive effects on COD removal rates. The significant contribution of the free radical (.OH) reaction pathway to PPG ozonation could be traced using tert-butyl alcohol as the .OH probe compound at varying concentrations. The bimolecular reaction rate constants for the direct reaction of PPG with ozone were found as 152 and 2404 M-1 h-1 at pH=3 and 7, respectively, using the gas phase ozone partial pressures determined from of the outlet gas stream analysis. It could be demonstrated that ozone decomposition to free radicals being triggered by increasing the pH from 3 to 7 is essential for the rate enhancement of PPG effluent ozonation.     

Cobalt and zinc removal from aqueous solution by chemically treated bentonite

Natural bentonite was treated by hydrochloric, nitric, and phosphoric acids followed by washing with sodium hydroxide in order to enhance its adsorption capacity. The sample that treated with hydrochloric acid followed by further treatment with NaOH showed the highest cation exchange capacity with a value of 51.20 meq/100 g. The zero-point of charge for this sample was found to be 4.50. Adsorption isotherms for both cobalt and zinc were fitted using Langmuir, Freundlich, and Redlich-Peterson and showed an adsorption capacity of 138.1 mg Co²⁺ and 202.6 mg Zn²⁺ per gram of treated sample.     

Multi‐Criteria Decision Support Systems for Flood Hazard Mitigation and Emergency Response in Urban Watersheds1

Abstract: Flood management problems are inherently complex, time‐bound and multi‐faceted, involving many decision makers (with conflicting priorities and dynamic preferences), high decision stakes, limited technical information (both in terms of quality and quantity), and difficult tradeoffs. Multi‐Criteria Decision Support Systems (MCDSS) can help to manage this complexity and decision load by combining value judgments and technical information in a structured decision framework. A brief overview of MCDSS is presented, an original MCDSS architecture is put forth, and future research directions are discussed, including extensions to Multi‐Criteria Spatial Decision Support Systems and group MCDSS (as flood management involves shared resources and broad constituencies). With application to the September 11‐12, 2000 Tokai floods in Japan, the proposed multi‐criteria decision support instruments enhance communication among stakeholders and improve emergency management resource allocation. In summary, by making the links among flood knowledge, assumptions and choices more explicit, MCDSS increases stakeholder satisfaction, saves lives, and reduces flood management costs, thereby increasing decision‐making effectiveness, efficiency and transparency.     

Study of water quality of Hudiara drain, India-Pakistan

This paper examines the extent of pollution in Hudiara drain water due to untreated industrial and sewage waste of India and Pakistan. Ninety-nine surface water samples from the Pakistani side of the Hudiara drain were collected during September 1997, and April and June 1998. The analytical results of the Hudiara drain samples point out the industrial and sewage inputs from India and Pakistan. Higher values of biochemical oxygen demand (BOD), chemical oxygen demand(COD), total organic carbon(TOC), and trace metals in drain samples from the Indo-Pak border clearly indicate the Indian industrial and sewage pollution. Large variations in the levels of various measured parameters (COD, BOD, TOC, pH, total soluble substances, and trace metals) were observed along the Hudiara drain in the Pakistani vicinity. These variations were due to different types of industrial effluents and small village drains. The study showed that suspended solids(SS), COD, and fecal coliform (FC) were the major pollutants. Accordingly, the most feasible alternative is to convert the drainage network to a sedimentation and temporary storage reservoir. If disinfected, the runoff water can be used for restricted irrigation. Groundwater samples taken from the drain's surrounding area have also been analyzed. Thirty percent of the samples are not fit for drinking purposes due to NO3-N, Se and FC counts as prescribed by World Health Organization (WHO) guidelines. A trilinear diagram clearly indicates the influence of surface water of the Hudiara drain on ground water; moreover, higher values of nitrate and FC clearly indicate the seepage from the Hudiara drain.     

Mineral potential and scope of investment in the Republic of Yemen

On 22 May 1990 the Yemen Arab Republic and Peoples Democratic Republic of Yemen were unified to form the Republic of Yemen, with a population of about 14 million people in an area of about 580 000 km². The Republic of Yemen is hoping to develop its mineral industry. Possessing a well established geological database plus a newly issued mining law and investment law, Yemen is inviting all investors, whether from the Yemeni private sector or foreign companies, either solely or in joint ventures to investigate opportunities in minerals and construction and industrial materials.     

Functional wildlife parks: The views of Kenyan children who live with them

This study reports on Kenyan school children's ideas about wildlife parks in their country. A comparison is made between the responses of school children in primary school, before they receive any science education, and those of secondary school pupils at the end of the secondary cycle. The findings show little difference between the two groups of students in terms of their ideas about wildlife parks. This has serious implications for science and environmental education in Kenya. Parks are understood by these pupils in terms of real life issues, as derived from social consequences. The children's ideas are all based on the role that parks play in society, but the function of parks to support biodiversity conservation does not seem to be important to the students. While it is satisfying to note that the school children have a good understanding of parks in their social context, it is essential to address fully the scientific and ecological role of parks in order that biodiversity becomes more valued in our society.