Pesticide resistance externalities and optimal mosquito management

A simultaneous equation model of the behavior of a mosquito abatement district based on biological and economic data is presented. Results indicate high long term costs if heavy reliance on chemical pesticide control methods continue, due to a pesticide resistance buildup in the mosquito populations. Physical source reduction methods were shown to be more efficient both in the short and long run. A linear programming model is presented which optimizes the inix of chemical and physical control methods. Results indicate increasing costs of mosquito abatement as pesticide effectiveness declines.     

Seasonal concentrations of lead in outdoor and indoor dust and blood of children in Riyadh,Saudi Arabia

Because detrimental effects of exposure to lead (Pb) on human health have been observed, we previously investigated concentrations of Pb in water supplies and blood of adult residents of Riyadh, Saudi Arabia. The objectives of the present study were to: (1) examine seasonal rates of deposition of Pb in dust in several areas of Riyadh city, (2) measure concentrations of Pb in both outdoor and indoor dust, (3) compare concentrations of Pb in dust in Riyadh with those reported for other cities, and (4) quantify Pb in blood of children living in Riyadh. Mean, monthly deposition of PB in outdoor dust was 4.7 × 10¹ ± 3.6 tons km^?2, with a mean Pb concentration of 2.4 × 10² ± 4.4 × 10¹ μg/g. Mean, monthly deposition of Pb in indoor dust was 2.7 ± 0.70 tons km^?2, with a mean concentration of 2.9 × 10¹ ± 1.5 × 10¹ μg Pb/g. There was a significant (P < 0.01) correlation between concentrations of Pb in outdoor and indoor dust. There was no correlation between concentrations of Pb in indoor dust and that in blood of children of Riyadh, whereas there was a weakly significant (P < 0.05) correlation between concentrations of Pb in outdoor dust and that in blood of children. The mean (±SD) concentration of Pb in blood of children in Riyadh was 5.2 ± 1.7, with a range of 1.7–1.6 × 10¹ μg/dl. Concentrations of Pb in blood of 17.8 % of children in Riyadh were greater than 10 μg/dl, which is the CDC’s level of concern.     

Procedures for outlier detection in circular time series models

It is known that the occurrence of outliers in linear or non-linear time series models may have adverse effects on the modelling and statistical inference of the data. Consequently, extensive research has been conducted on developing outlier detection procedures so that outliers may be properly managed. However, no work has been done on the problem of outliers in circular time series data. This problem is the focus of this paper. The main objective is to develop novel numerical and graphical procedures for detecting these outliers in circular time series data.A number of circular time series models have been proposed including the circular autoregressive model. We extend the iterative outlier detection procedure which has been successfully used in linear time series models to the circular autoregressive model. The proposed procedure shows a good performance when investigated via simulation for the circular autoregressive model of order one. At the same time, several statistical techniques have been used to detect the change of preferred trend in time series data using SLIME and CUSUM plots. While the methods fail to indicate directly the outliers in circular time series data, we use the ideas employed to develop three novel graphical procedures for identifying the outliers. For illustration, we apply the procedures to a particular set of wind direction data. An agreement between the results of the graphical and iterative detection procedures is observed. These procedures could be very useful in improving the modelling and inferential processes for circular time series data.     

Occupational injuries and health problems in the Egyptian Mediterranean fisheries

Marine fishing is one of the most dangerous occupations. So far, no studies addressing occupational safety and health in the Egyptian fisheries have been conducted. The objective of this study is to explore and identify the types and causes of, as well as some factors associated with, occupational accidents and illnesses in the Egyptian marine fisheries. A sample of 686 fishermen in El-Maaddiya fishing port were interviewed for collecting relevant data. This paper presents the types of injuries mentioned by the interviewed fishermen and their potential causes in terms of accident type and involved agency/agency part. Also, major health problems and potential causes are presented. Furthermore, a logistic regression analysis was performed to study the significance of the association of some factors, such as age, experience, education and fishing gear with the occurrence of injuries and illnesses. The results of this study show that the Egyptian fishing industry involve many hazardous work conditions and practices that result in high morbidity and mortality rates, and high injury rates. The study recommends further research on suitable measures for the management of this problem.     

Field evaluation of intensive compost application on Cd fractionation and phytoavailability in a mining-contaminated soil

A field experiment was conducted to investigate the effect of chicken manure compost on the fractionation of cadmium (Cd), soil biological properties and Cd uptake by wheat in a soil affected by mining activities in Hubei province, China. Compost was applied at five levels (0, 27, 54, 108, 216 t ha^?1), and winter wheat (Triticum aestivum L.) was chosen as an indicator plant. Results showed that the application of compost increased soil pH and the content of total phosphorus and organic matter. Soil biological properties such as microbial biomass carbon, invertase, protease, urease and catalase activities were significantly enhanced by 0.24–3.47 times after compost application. Sequential extraction indicated that compost amendments decreased the acid-extractable Cd by 8.2–37.6 %, while increased the reducible and oxidisable Cd by 9.2–39.5 and 8.2–60.4 %, respectively. The addition of 27–54 t ha^?1 compost reduced Cd content in wheat stems and seeds by 69.6–75.0 % and 10.3–18.4 %, respectively. However, only 25.5–26.5 % reductions in Cd content in wheat stems were observed in 108–216 t ha^?1 compost amendments, and no significant decrease was detected for seeds. This study suggests that although compost is a suitable organic amendment to improve soil fertility and biological activities, the addition of compost should be moderated by an appropriate rate to optimize the use of compost for the reclamation of metal-contaminated soils at field scale.     

Biosynthesis of iron nanoparticles and their application in removing phosphorus from aqueous solutions

This paper reports the biosynthesis of nanoscale zero-valent iron (nZVI) using the extracts of Shirazi thyme leaf (Th-nZVI) and pistachio green hulls (P-nZVI). Scanning electron microscopy verified the successful synthesis of the poorly crystalline nZVI with a spherical shape and diameter in the range of 40–70 nm. According to X-ray diffraction and Fourier transform infrared spectroscope analyses, the synthesised nZVI were composed of iron oxides nanoparticles and ployphenol obtained from Shirazi thyme leaf and pistachio green hulls extracts acting as both reducing and capping agents. The phosphorus removal efficiency of Th-nZVI and P-nZVI increased with time and reached equilibrium at about 4 and 2h, respectively. Sorption of phosphorus on both sorbents was observed to be pH-dependent with maximum phosphorus removal occurring in the pH range of 2–5. Langmuir, Freundlich, Redlich–Peterson, and Temkin models were used to describe phosphorus sorption at pH 5 and maximum sorption capacity for Th-nZVI and P-nZVI was about 40.52 and 29.33?mg?g^?1, respectively. Correlation coefficient (R²) and standard errors of estimate showed that the Elovich model was better than other models at describing the kinetic data. These results suggested that the synthesised nZVI with Shirazi thyme leaf and pistachio green hulls extracts could be employed as an efficient sorbent for the remediation of phosphorus from contaminated water sources.     

Propetamphos enhances chlorpyrifos-induced organophosphate-induced delayed neurotoxicity (OPIDN) in Hens: a role for plasma butyrylcholinesterase

This study examined dose-response effects of chlorpyrifos (CPF) and propetamphos (PRO) on producing organophosphorus-induced delayed neurotoxicity (OPIDN) in hens. A single oral dose of 1, 3, 30, or 100 mg/kg of each compound was administered individually, or in combination to groups of 10 hens. Plasma butyrylcholinesterase (BChE) activity was inhibited by all doses of each individual compound. Chlorpyrifos alone or in combination with PRO resulted in decreased acetylcholinesterase (AChE) activity. No dose of CPF or PRO alone resulted in the inhibition of neuropathy target esterase (NTE) or produced OPIDN. In contrast, combined exposure to high doses of CPF and PRO produced diminished NTE activity and produced OPIDN. Brain NTE activity was decreased by 67% and 71% by combined treatment of 100 mg/kg CPF with 30 mg/kg and 100 mg/kg PRO, respectively, consistent with the development of ataxia and paralysis, characteristic of OPIDN. Only the highest dose of CPF 100 mg/kg interacted with the two highest doses of PRO to block NTE and induce OPIDN, whereas no marked interaction occurred at lower doses. Data indicate that PRO enhances the ability of high doses of CPF to produce OPIDN by binding to plasma BChE that appears to act as a buffering system to modulate the toxicity of CPF. In effect, the ability of BChE to bind to CPF is diminished by PRO, resulting in more CPF delivery to the brain, and subsequent development of OPIDN at a dose that does not initiate this effect by itself.     

Hybrid process-criterion benchmarking methodology framework to support sustainability performance assessment and reporting

The conception, design, and implementation of sustainable development strategies in an organization aims at meeting and balancing economic, social, and environmental needs of internal and external stakeholders. While the principles and fundamentals of sustainability assist during the conception and design phases, the implementation process of management strategies – impacted directly or indirectly by internal and external factors – may identify areas of competitive advantages or challenges that would impede the projects and organizations’ performance targets. An organization is not an isolated entity and its performance is often compared against others in the market arena; therefore, assessment tools, benchmarking processes, and reporting strategies become essential for the understanding of the efforts made towards the implementation of plan, policies, and programs at the organization and project levels. A framework for a hybrid process-criterion benchmarking methodology is proposed in this paper. The framework integrates the Rank Xerox benchmarking process and the Wa-Pa-Su project sustainability rating system assessment methodology. The proposed hybrid process-criterion benchmarking methodology encourages the diversification in the development and implementation of sustainable and environmental rating systems in industry contexts (e.g., oil and gas, mining, heavy industrial, and energy) and aims for the improvement of existing sustainability performance assessment and reporting practices. It also assists the quantitative assessment process of advances and/or setbacks in sustainability performance and the implementation of continuous performance improvement programs.     

Selenium and nano-selenium in plant nutrition

Selenium (Se) is a naturally occurring metalloid element which occurs nearly in all environments. Se is considered as a finite and non-renewable resource on the Earth. The common sources of Se in earth’s crust occur in association with sulfide minerals such as metal selenide, whereas it is rarely found in elemental form (Se⁰). While there is no evidence of Se need for higher plants, several reports show that when Se added at low concentrations, Se exerts beneficial effects on plant growth. Se may act as quasi-essential micronutrient through altering different physiological and biochemical traits. Thus, plants vary considerably in their physiological and biochemical response to Se. This review focusses on the physiological importance of Se forms as well as different Se fertilizers for higher plants, especially plant growth, uptake, transport, and metabolism.     

Is animal welfare a central issue for consumers of luxury goods?

The compatibility between luxury and sustainable development has been increasingly examined in recent literature, but a number of ethical issues remain unexplored. One such concern is animal welfare, a recurrent question in the luxury goods sector. This is one of the first research articles to shed light on this subject, utilising two studies, one qualitative and the other quantitative with conjoint analysis, conducted among 12 and 253 French consumers, respectively. The results reveal that consumers are sensitive to the challenge of animal welfare in luxury, but fall into two different groups. Some have a preference for animal‐based raw materials sourced from livestock farms that respect animal welfare, whilst others are more favourable to the use of synthetic raw materials. In particular, the results show that the use of synthetic raw materials is accepted by some consumers but can lead to a reduction in the perceived value of luxury products.