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The purpose of this paper is to examine the dependency of dispersion and damping behavior of Love-type waves on wave number in a heterogeneous dry sandy double layer of finite thickness superimposed on heterogeneous viscoelastic substrate under the influence of hydrostatic initial stress.

The mechanical properties of the material of both the dry sandy layers vary with respect to a certain depth as quadratic and hyperbolic function, while it varies as an exponential function for the viscoelastic semi-infinite medium. The method of the separation of variables is employed to obtain the complex frequency equation.

The complex frequency equation is separated into real and imaginary components corresponding to dispersion and damping equation. After that, the obtained result coincides with the pre-established classical equation of Love wave, as shown in Section 5. The response of all mechanical parameters such as heterogeneities, sandiness, hydrostatic stress, thickness ratio, attenuation and viscoelasticity on both the phase and damped velocity against real wave number has been discussed with the help of numerical example and graphical demonstrations.

In this work, a comparative study clarifies that the Love wave propagates with higher speed in an isotropic elastic structure as compared to the proposed model. This study may find its applications in the investigation of mechanical behavior and deformation of the sedimentary rock.

The importance of early and developmentally appropriate science education is increasingly recognized. Consequently, creation of common guidelines and standards in early childhood science education has begun (National Research Council (NRC), 2012), and researchers, practitioners, and policy makers have shown great interest in aligning professional development with the new guidelines and standards. There are some important issues that need to be addressed in order to successfully implement guidelines and make progress toward accomplishing standards. Early childhood teachers have expressed a lack of confidence in teaching science and nature (Torquati, Cutler, Gilkerson, & Sarver, in press) and have limited science and pedagogical content knowledge (PCK) (Appleton, 2008). These are critical issues because teachers’ subject-matter knowledge is a robust predictor of student learning outcomes (Enfield & Rogers, 2009; Kennedy, 1998; Wilson, Floden, & Ferrini-Mundy, 2002) and is seen as a critical step toward improving K-12 student achievement (National Commission on Mathematics and Science Teaching for the 21st Century (NCMST), 2000; NRC, 2000). We argue that the same is true of preschool teachers.

This chapter discusses: (a) theories and practices in early childhood science education (i.e., preschool through 3rd grade) in relation to teaching for conceptual change, (b) research on methods of professional development in early childhood science education, and (c) innovative approaches to integrating scientific practices, crosscutting concepts, and disciplinary core ideas with early childhood professional development.

This study aimed to find out the information needs of illiterate female farmers in Ethiope East local government area of Delta State, Nigeria. Agriculture is the mainstay of people in the rural areas, and is mostly for subsistence living. To bring about improvement in practice requires finding out: at what stages of farming illiterate female farmers need agricultural information; through which channels they receive agricultural information; the problems they encounter when they need information; and how the problem can be solve.

The study sample consisted of 200 illiterate female farmers. Data was collected via structured questionnaire, which was read and translated to the illiterate female farmers in their local dialect, Urhobo.

Analysis of the data revealed that the illiterate female farmers do not have access to information because the agricultural extension services unit fails to visit them and provide the required agricultural information. Cassava is the major crop produced by illiterate female farmers in the Abraka and Agbon clans. Community/opinion leaders and children of farmers are the main sources of agricultural information for illiterate female farmers. Lack of funds to purchase radio/television so as to have access to programmes on better farming techniques was a major problem; as was the lack of a mobile library to visit the farmers and provide necessary agricultural information.

Highlights the problems of illiterate indigenous people accessing information on agriculture that if applied should lift them above subsistence level.

Gore supports IT Will the next Vice President of the United States push information technology to the forefront of America's domestic policy? It may well happen because Al Gore has played a leading role in the Senate as Chairman of the Sub‐committee on Science, Technology and Space and as a leading member of a group of Democratic Senators that believe investment in IT is one way out of the country's current economic doldrums.

The purpose of this paper is to demonstrate that agricultural commodity value chain development using multi-stakeholder partnerships (MSPs) can fast-track improvement in the livelihoods of rural farming households. With the view that such partnerships can raise farmers’ incomes, the study uses the case of the organic pineapple (OP) value chain in Ntungamo, Western Uganda, to understand the governance features that hold the value chain partners together, to analyse the costs and margins to the participating farmers, to identify opportunities for demand-driven upgrading of the farmers’ skills and knowledge, and the role that partnerships play in such upgrading.

The study uses the qualitative tools of value chain analysis: value chain maps of stakeholders, processes and support services of the OP value chain, and a quantitative tool to analyse costs and margins to the participating farmers. Interviews were conducted with key informants from the OP innovation platform, and survey data collected for the planting season, February–July, 2014, across three farmer categories of certified organic, conventional, and farmers not participating in the innovation platform.

Careful selection of partnerships to develop the value chain is found to be critical. Partners to involve should be those that enable the upgrading of farmers’ knowledge, skills and technologies to position them for better markets. Partners should also include those that enable the improvement of margins to the farmers and efficiency of the value chain. The strategic MSPs should be bound by formal contracts, to ensure stable relationships in the value chain and hence sustainable market access for the farmers.

Although carried out on a specific value chain in a specific local context, this is not likely to limit the applicability of the findings to commodity value chains in a range of local contexts.

The study fulfils the need to highlight the role that stakeholder partnerships can play in value chain development and how they can be sustained by governance and institutional arrangements.

A systematic, disciplinary approach to setting preservation priorities developed at Mann Library is described. The Core Agricultural Literature project, under the direction of Wallace C. Olsen, has identified the core historical literature in seven disciplines comprising the agricultural sciences. Specific applications and adaptations of the core literature methodology in three other biology and agriculture preservation projects are discussed. Two of the four preservation projects briefly described here have been undertaken as part of a national preservation plan for agricultural sciences literature. The application of digital technology in a national cooperative effort to preserve core historical literature of agriculture represents the culmination of Mann Library's work in developing a disciplinary approach to national preservation planning.

This article focuses on attempts to introduce elements of sustainable development education into the curriculum of one of the largest Russian universities. At St Petersburg State University, compulsory courses relevant to sustainable development have been introduced or modified in 14 faculties out of 20 during the last decade. Examples of environmentally oriented projects within and outside the university are given. The authors touch upon the state of affairs in higher education in Russia, and write about sustainable development in a wider sense, beyond the environmental context. Sustainable development in education for Russia is one of the most important prerequisites for sustainable development in society. A model for reforming the system of national higher education is given to illustrate possible ways of achieving sustainability in education.

This paper aims to assess the farming community’s perception on important parameters of climate change and identify major practices and technologies adopted to mitigate the impacts of climate change and their determinants in mountain district of Nepal. Being an agrarian economy and dependent on monsoon rain, the impact of climate change on agricultural productivity and production has been experienced. Different adaptation strategies have been adopted by the communities to cope with the consequences of climate change.

Four village development committees (VDCs) situated in the buffer zone of Langtang National Park of Rasuwa district representing rice, wheat, maize and potato production area was purposively selected for this study. A two-stage sampling technique was adopted for data and information collection. Thirty households from each VDC were randomly selected. Data on the socio-economic and climate change perception were collected using structured questionnaire. A binary logistic regression technique was used to identify the determinants of climate change adaptation technologies and practices.

The farmers’ decisions whether to adopt climate change adaptation technologies are governed by the size of landholding, perceived threat of climate change to food security, education level and gender of the interviewee, perception on the increased incidence of droughts during rainy season and income received from the off-farm sources. In a community where agricultural activity is the dominant means of living, adaptive strategies help to increase the capacity of a farming system to survive external shocks and cope with the consequences.

The assessment of farm-level adaptation strategies and factors influencing their adoption decision is important to formulate policies and design programs. This will also help to recognize adaptation as a tool for managing a variety of risks associated with climate change in agricultural sector.

This study aims to evaluate the effect of Piper betle leaf extract towards the acute-lethal toxicity, LC50 of red Nile tilapia juveniles (Oreochromis niloticus).

Ten red Nile tilapia juveniles per tank (in triplicate) were used as an experimental fish for the LC50 bioassay. Five different concentrations of P. betle extract; 80 ppm, 90 ppm, 100 ppm, 110 ppm and 120 ppm, were tested on the red Nile tilapia juveniles and one tank was acting as a control. The progress of the LC50 and lethal time of fish mortality were observed and recorded within the random interval of 96 h. The value for LC50 was determined as 100 ppm of P. betle leaf extract. Higher number of fish mortalities was observed when concentration higher than 100 ppm was tested on to the red Nile tilapia juveniles.

Data obtained shows that the P. betle concentration of 120 ppm accelerated the fish mortality period.

However, adaption of P. betle extract occurred after 50 h, as there was no fish mortality observed within the time.