Design and development of novel insect growth regulators: Synthesis,characterization and effect of benzoyl thymyl thioureas and ureas on total haemocyte count of Dysdercus koenigii

Insect-growth regulators (IGRs) have been receiving foremost attention as potential means of selective insect control. Benzoyl phenyl urea (BPU) is a well-known IGR having chitin synthesis inhibitor activity. Mimics of BPU have been synthesized by suitable derivatization of a naturally occurring monoterpenoid, thymol (2-isopropyl-5-methyl phenol) to form a = series of substituted benzoyl thymyl thioureas (BTTUs) [IVa-f] and benzoyl thymyl ureas (BTUs) [Va-f]. The synthesized compounds have been characterized by ¹H and ¹³C NMR, LC-MS and elemental analysis. These derivatives have been screened for their effect on total haemocyte count of Dysdercus koenigii. It has been observed that the introduction of substituted benzoyl thiourea and urea linkage into a thymol ring via an amino group results in higher activity than the parent compound thymol and a comparable pattern of results with the standard insect-growth regulators, Penfluron. Urea [Va-f] compounds exhibited greater effect on Total Haemocyte Count (THC) than thiourea [IVa-f]. Fluoro substitution enhanced the effect on THC more than chloro substituted compounds, while ortho-substitution resulted in a better effect than para-substitution. The results described in this paper are promising and provide new array of synthetic chemicals that may be utilized as insect growth regulators.     

Agricultural GHG emission and calorie intake nexus among different socioeconomic households of rural eastern India

A study was conducted to examine the interrelationships among socioeconomic factors, household consumption patterns, calorie intake and greenhouse gas emissions factors in rural eastern India based on household survey data. Findings indicated that higher monthly per capita incomes (12.1–80.1$) were associated with greater average calorie intakes (2021–2525 kcal d^?1). As estimated by the FEEDME model, in total 17.2% of the population was calorie malnourished with a regional disparity of 29.4–18.2% malnourishment. Greenhouse gas (GHG) emissions were calculated only on the basis of crop and livestock production and consumption. Rice accounted for the highest share of total GHG emissions, on average 82.6% on a production basis, which varied from 58.1% to 94.9% in regional basis. Rice contributed the greatest share (~?65% and 66.2%) in terms of both calories and GHG emissions (CO₂ eq y^?1), respectively, on a consumption basis. We conclude that extensive rice farming and increasing animal product consumption are dominant factors in the higher carbon footprint in this region and are likely to further increase with increase in per capita income. This study provides useful information to help for better crop planning and for fine-tuning food access policy, to reduce carbon footprint and calorie malnutrition.

     

Mate replacement in experimentally widowed collared flycatchers (Ficedula albicollis): determinants and outcomes

There is increasing evidence that sexual selection may be intense even in socially monogamous birds, resulting from both mate choice and sperm competition. We studied these two modes of sexual selection experimentally by removing paired male collared flycatchers, Ficedula albicollis, from their mates for 2 days and investigating the factors that influenced the likelihood of a replacement male appearing and how the removals influenced paternity. Replacement males (usually neighbouring males) appeared at 81% (n = 37) of nests where males were removed. The likelihood of this appearance was unaffected by the probable reproductive value of the female's clutch to the replacing male. A replacement was, however, less likely when the original male had a large forehead patch, a trait previously shown to be subject to sexual selection in this population. Experimental removal of males increased the level of sperm competition: 74% of experimental broods were multiply sired, compared to 29% of unmanipulated broods in a previous study. Only two factors predicted how paternity was shared between males: removed males fathered more young if removed closer to laying, and if they had larger forehead patches. The former result is consistent with last-male sperm precedence determining paternity, whereas the latter adds to other evidence that forehead patch size is the target of female preference in this species. Our results suggest that females exert some control over male replacement, and also that they may influence the fertilisation success of males by behavioural means. Received: 15 July 1998 / Received in revised form: 16 March 1999 / Accepted: 28 March 1999     

Government Sponsored Air Pollution Research Relating to Agriculture

The absorption of hydrogen sulfide and methyl mercaptan by aqueous solutions of chlorine, sodium hydroxide, and chlorine plus sodium hydroxide was studied using a two-inch diameter absorption column packed with ¼ inch Intalox saddles. Absorption rates were noticeably affected by chemical reactions occurring in the aqueous chlorine and hydroxide media. These solutions were studied as a means of controlling sulfur-containing gas emissions from kraft paper mills. The absorption studies indicated that aqueous chlorine solutions at a pH above 12 were effective absorbents for hydrogen sulfide removal in absorption equipment designed to tolerate sulfur in suspension. The absorption of methyl mercaptan in aqueous chlorine solutions appeared to be impractical since dimethyl disulfide was apparently the only product formed and was stripped from the tower by the gas stream. Sodium hydroxide solution was an effective absorbent for both methyl mercaptan and hydrogen sulfide when hydroxide to sulfide or mercaptan feed ratios were greater than 1 or 1.8, respectively. The mercaptan absorption coefficient was approximately twice that for sulfide absorption.     

Understanding and enhancing future infrastructure resiliency: a socio‐ecological approach

The resilience of any system, human or natural, centres on its capacity to adapt its structure, but not necessarily its function, to a new configuration in response to long‐term socio‐ecological change. In the long term, therefore, enhancing resilience involves more than simply improving a system's ability to resist an immediate threat or to recover to a stable past state. However, despite the prevalence of adaptive notions of resilience in academic discourse, it is apparent that infrastructure planners and policies largely continue to struggle to comprehend longer‐term system adaptation in their understanding of resilience. Instead, a short‐term, stable system (STSS) perspective on resilience is prevalent. This paper seeks to identify and problematise this perspective, presenting research based on the development of a heuristic ‘scenario–episode’ tool to address, and challenge, it in the context of United Kingdom infrastructure resilience. The aim is to help resilience practitioners to understand better the capacities of future infrastructure systems to respond to natural, malicious threats.     

Data,data everywhere but not a byte to read: Managing monitoring information

The problem of managing scientific information for widespread availability and use can be overwhelming. At Oregon State University, the Quantitative Sciences Group has found a workable solution. The group has developed a Forest Science Data Bank (FSDB) to house data generated by scientists and collaborating researchers in the Andrews Long-Term Ecological Research program. Today the FSDB houses some 2400 data sets from over 350 existing ecological studies and adds about 20 new studies yearly. This paper describes what we have learned in setting up the FSDB as a facility that can be used by researchers who both deposit information in and retrieve information from the FSDB.     

Conducting in-depth accident studies

In 1983 the Accident Research Unit at the Institute for Consumer Ergonomics began a major study, sponsored by the UK Department of Transport and three motor companies, to investigate the causes of injury to occupants in car accidents. This study has been under way for nearly ten years and the database of information is one of the most comprehensive of its kind in the world. This information plays a key role in establishing the priorities for safety research in the UK, based on real life accident data. This paper is concerned with the practical aspects of the collection and analysis of real life accident data. Issues include the establishment and maintenance of collaboration with police forces, hospital consultants and coroners; recruitment and training of staff; accident sampling; data quality control and large scale project management. The case is also made for the need to establish a coordinated European database of accident information to facilitate the development of appropriate safety requirements and to set priorities for safety research in Europe.     

Microclimate influence in a physiological model of cattle-fever tick (Boophilus spp.) population dynamics

Since their official eradication from the US in 1943, the cattle-tick species Boophilus microplus and Boophilus annulatus, vectors of bovine babesiosis, frequently have penetrated a quarantine zone established along the Texas–Mexico border designed to exclude them. Inspection and quarantine procedures have eradicated reinfestations successfully within the US, but increasing acaricide resistance in Mexican B. microplus populations poses a threat to future eradication efforts. Better understanding of interrelationships among Boophilus populations, their hosts, and vegetation communities in south Texas could improve prediction of the behavior of reintroduced Boophilus populations and increase management options. To this end, we constructed a simulation model to evaluate how microclimate, habitat (i.e. vegetation) heterogeneity, and within-pasture cattle movement may influence dynamics of Boophilus ticks in south Texas. Unlike previous Boophilus tick models, this model simulates dynamics at an hourly time-step, calculates all off-host dynamics as functions of temperature and relative humidity, and runs with ground-level microclimate data collected bi-hourly in three different habitat types. Sensitivity analysis of the model showed that temperatures and relative humidities created by habitat type, as well as engorged female mass, influenced tick population dynamics most strongly. Host habitat selection, initial number of larvae per cow, and the number of cells into which the simulated pasture was divided also had a strong influence. Population dynamics appeared moderately sensitive to the proportion of Bos indicus in cattle genotypes and the larval attachment rate, while appearing relatively insensitive to factors such as mortality rate of engorged females. When used to simulate laboratory experiments from the literature, the model predicted most observed life-history characteristics fairly well; however, it tended to underestimate oviposition duration, incubation duration, and egg mortality and overestimate larval longevity, especially at low temperatures and high humidities. Use of the model to predict Boophilus population dynamics in hypothetical south Texas pastures showed that it reasonably generated qualitative patterns of stage-wise abundances but tended to overestimate on-host tick burdens. Collection and incorporation of data that appear not to exist for Boophilus ticks, such as larval lipid content and lipid-use rates, may improve model accuracy. Though this model needs refinements such as a smaller spatial resolution, it provides insight into responses of B. microplus or B. annulatus populations to specific weather patterns, habitat heterogeneity, and host movement.     

Survey and evaluation of contaminants in earthworms and in soils derived from dredged material at confined disposal facilities in the Great Lakes Region

Soils derived from dredged material were collected, together with earthworms from nine confined disposal facilities located in the Great Lakes Region. These samples were analyzed for 18 elements, 11 organochlorine pesticides, PCBs, and 24 polycyclic aromatic hydrocarbons. The concentrations detected in earthworms were evaluated in terms of their potential hazard to wildlife, which for the sake of the evaluation were assumed to prey entirely either on earthworms or on other soil invertebrates having similar concentrations. The soil concentrations (dry wt.) of the contaminants of greatest concern were <1.9 to 32 ppm Cd, <0.053 to 0.94 ppm Hg, 4.6 to 550 ppm Pb, and <0.1 to 1.0 ppm PCBs. The concentrations in earthworms (dry wt., ingested soil included) were as high as 91 ppm Cd, 1.6 ppm Hg, 200 ppm Pb, and 1.8 ppm PCBs. Based on laboratory toxicity studies of relatively sensitive species, and on concentration factors calculated from the earthworm and soil data, we estimated that lethal or serious sublethal effects on wildlife might be expected at concentrations of 10 ppm Cd, 3 ppm Hg, 670 ppm Pb, and 1.7 ppm PCBs in alkaline surface soils derived from dredged material. Concentrations of polycyclic aromatic hydrocarbons in earthworms were well below those in soil.     

Fatal and serious collisions involving pedal cyclists and trucks in London between 2007 and 2011

Objective: Increased numbers of people riding pedal cycles have led to a greater focus on pedal cycle safety. The aim of this article is to explore factors that are associated with fatal and a small number of serious-injury pedal cyclist crashes involving trucks that occurred in London between 2007 and 2011.

Methods: Data were collected from police collision files for 53 crashes, 27 of which involved a truck (≥3.5 tonnes) and a pedal cycle. A systematic case review approach was used to identify the infrastructure, vehicle road user, and management factors that contributed to these crashes and injuries and how these factors interacted.

Results: Trucks turning left conflicting with pedal cyclists traveling straight ahead was a common crash scenario. Key contributory factors identified included the pedal cyclists not being visible to the truck drivers, road narrowing, and inappropriate positioning of pedal cyclists.

Conclusions: Crashes involving trucks and pedal cyclists are complex events that are caused by multiple interacting factors; therefore, multiple measures are required to prevent them from occurring.