Nutrition and development of brooded embryos in the brittlestar Amphipholis squamata: do endosymbiotic bacteria play a role?

To identify sources of nutrition potentially available to the yolk-deficient embryos of the brooding brittlestar Amphipholis squamata Della Chiaje, (= Axiognathus squamata, Thomas 1966), specimens were collected intertidally at all seasons (1986 through 1987) from Odiorne Point, Rye, New Hampshire and from Appledore Island, Isles of Shoals, Maine, USA. Ultrastructural, autoradiographic and immunohistochemical studies were made of adults and brooded embryos. Adult and embryonic tissues have morphological adaptations which support healthy, symbiotic bacteria (5 to 9 x 10⁶ colony forming units/adult brittlestar), while autoradiographic studies indicate direct uptake of labeled amino acids by eukaryotic host tissues and bacteria. Cell envelopes of subcuticular bacteria suggest that they are Gram negative and may belong in the genus Vibrio. Based on immunohistochemical localization, it appears that a single type of bacterium is present in large numbers under the cuticles of embryos and adults of A. squamata. This is the first study of the relationship between an echinoderm and a bacterium which includes isolation and immunohistochemical verification of the identity of the bacterial symbiont.     

An assessment of attraction toward affirmative action organizations: investigating the role of individual differences

Our study investigated applicant characteristics in response to organizations incorporating an affirmative action policy (AAP) statement in recruitment material. Study participants (N = 217; White upper‐level management students) randomly received recruitment material containing one of three statements (e.g., affirmative action, equal employment opportunity (EEO), or no statement regarding affirmative action or EEO) and were asked to evaluate the attractiveness of the organization publicizing the designated policy. Results indicated that individuals responded negatively to AAPs in recruitment material because of prejudice attitudes, the perceived unfairness of such programs (which we relate to equity sensitivity), or in an attempt to protect their own self‐interest (which we relate to general self‐efficacy). Additionally, individuals' equity sensitivity and general self‐efficacy both moderated the relationship between racial prejudice and organizational attractiveness. Specifically, the negative relationships between participants' prejudice attitudes and the attractiveness of organizations publicizing an affirmative action policy were stronger for benevolents (persons tolerant of situations where they are under‐rewarded) and for persons low in self‐efficacy. Implications of our findings for organizational recruitment practices are discussed. Copyright © 2006 John Wiley & Sons, Ltd.     

Leader–member social exchange (LMSX): development and validation of a scale

In the last 10 years, research devoted to the construct of leader–member exchange (LMX) has increasingly relied on the tenets of social exchange as a theoretical foundation to propose and test relationships between supervisor‐subordinate dyads and variables of significant consequence. Despite the theory underpinning such relationships, researchers continue to measure LMX with scales developed to assess vertical dyad linkage (VDL), not social exchange. To address this concern, we investigated the content validity of LMX7 (the most widely cited measure of LMX) and LMX‐MDM (a popular multidimensional measure of LMX). Findings from content validity assessments by 25 LMX experts revealed LMX7 and LMX‐MDM items are not representative of the construct of social exchange. As such, we undertook a series of studies to develop a new scale we label, leader–member social exchange (LMSX). Results indicate LMSX is able to assess different, as well as the same, components of the supervisor–subordinate relationship as previous scales while being more theoretically consistent with the notion of social exchange. Copyright © 2007 John Wiley & Sons, Ltd.     

Understanding the dynamics and competitiveness of the South African minerals inputs cluster

South Africa has developed niche competencies around the extraction and processing of mineral resources. Firms involved in the manufacture and supply of inputs to mining and mineral processing represent a key source of competitive advantage upon which future growth and development in the country can be planned. Drawing on a qualitative and quantitative study of 678 supplier firms conducted in 2004, this paper presents an assessment of the state of the South African minerals inputs cluster. The various demand and supply relationships, dynamics, and growth opportunities within the cluster are highlighted and the threats affecting the cluster's future competitiveness reviewed. The interventions needed to overcome and/or enhance them are also identified.     

Perspectives on social capacity building for natural hazards: outlining an emerging field of research and practice in Europe

Social capacity building for natural hazards is a topic increasingly gaining relevance not only for so-called developing countries but also for European welfare states which are continuously challenged by the social, economic and ecological impacts of natural hazards. Following an outline of recent governance changes with regard to natural hazards, we develop a heuristic model of social capacity building by taking into account a wide range of existing expertise from different fields of research. Particular attention is paid to social vulnerability and its assessment, as well as to risk communication and risk education as specific strategies of social capacity building. We propose to distinguish between interventionist and participatory approaches, thus enabling for a better understanding of existing practices of social capacity building as well as their particular strengths and weaknesses. By way of conclusion, we encourage more research on social capacity building for natural hazards in the European context which at present is highly diverse and, at least in parts, only poorly investigated.     

Issues associated with possible implementation of Non-Invasive Prenatal Testing (NIPT) in first-tier screening: A rapid scoping review

In recent years, as the implementation and use of Non-Invasive Prenatal Testing (NIPT) have increased, the cost of the test has been decreasing. The cost of NIPT is expected to fall further in the upcoming years. As a result of the decreasing cost of NIPT, many jurisdictions may change their prenatal screening policies toward abandoning serum-based screening and instead, implement and support NIPT as the first-tier screening for all women. There are several concerns in replacing first-trimester screening with NIPT. In this scoping review, we aimed to map the existing knowledge about possible issues in the systematic implementation of NIPT as the primary method of first-tier screening and to assess if any jurisdiction has altered its policy and discontinued serum-based prenatal screening in exchange for NIPT. The Medline database (Ovid) and Google Scholar was searched and all the studies discussing, investigating, or reporting on the systematic implementation of NIPT as the primary method of first-tier screening were included. All the studies went through a two-stage screening process and included full-text articles were reviewed. We did not find any articles indicating a country or region that replaced traditional prenatal screening by NIPT. The included articles were charted, and the data about the possible issues in the systematic implementation of NIPT as the primary method of first-tier screening are summarized narratively and presented in tables in four categories. The findings of this scoping review may be informative for stakeholders and policymakers regarding recent changes in NIPT implementation policies around the world and may aid with developing policy for NIPT implementation with a broader perspective.     

The influence of satellite populations of emerald ash borer on projected economic costs in U.S. communities, 2010-2020

The invasion spread of the emerald ash borer (Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae) is characterized by the formation of satellite populations that expand and coalesce with the continuously invading population front. As of January 2010, satellite infestations have been detected in 13 states and two Canadian provinces. Understanding how newly established satellite populations may affect economic costs can help program managers to justify and design prevention and control strategies. We estimate the economic costs caused by EAB for the 10-yr period from 2010 to 2020 for scenarios of fewer EAB satellite populations than those found from 2005 to 2010 and slower expansion of satellite populations found in 2009. We measure the projected discounted cost of treatment, removal, and replacement of ash trees (Fraxinus spp.) growing in managed landscapes in U.S. communities. Estimated costs for the base scenario with the full complement of satellites in 2005-2010 and no program to mitigate spread is $12.5 billion. Fewer EAB satellites from 2005 to 2010 delay economic costs of $1.0 to 7.4 billion. Slower expansion of 2009 satellite populations delays economic costs of $0.1 to 0.7 billion. Satellite populations that are both distant from the core EAB infestation and close to large urban areas caused more economic costs in our simulations than did other satellites. Our estimates of delayed economic costs suggest that spending on activities that prevent establishment of new satellite EAB populations or slow expansion of existing populations can be cost-effective and that continued research on the cost and effectiveness of prevention and control activities is warranted.     

Application of cupuassu shell as biosorbent for the removal of textile dyes from aqueous solution

The cupuassu shell (Theobroma grandiflorum) which is a food residue was used in its natural form as biosorbent for the removal of C.I. Reactive Red 194 and C.I. Direct Blue 53 dyes from aqueous solutions. This biosorbent was characterized by infrared spectroscopy, scanning electron microscopy, and nitrogen adsorption/desorption curves. The effects of pH, biosorbent dosage and shaking time on biosorption capacities were studied. In acidic pH region (pH 2.0) the biosorption of the dyes were favorable. The contact time required to obtain the equilibrium was 8 and 18 h at 298 K, for Reactive Red 194 and Direct Blue 53, respectively. The Avrami fractionary-order kinetic model provided the best fit to experimental data compared with pseudo-first-order, pseudo-second-order and chemisorption kinetic adsorption models. The equilibrium data were fitted to Langmuir, Freundlich, Sips and Radke-Prausnitz isotherm models. For both dyes the equilibrium data were best fitted to the Sips isotherm model.     

Book reviews

Making Cities Work: the role of local government in the urban environment. Richard Gilbert, Don Stevenson, Herbert Girardet &; Richard Stren, 1996, London, Earthscan, 203pp. ISBN 1 85383 354 1, £13.95 pbk

Environmental Policy in an International Context, Vols 1–3: Perspectives, Conflicts and Prospects. P. Glasbergen &; A. Blowers (Series Eds) London, Arnold

Rhetoric and Reality in Environmental Policy. M. Wintle &; R. Reeve (Eds), 1994, Aldershot, Avebury Studies in Green Research, 154 pp. ISBN 1 85628 927 3

FutureNatural: Nature, Science, Culture. G. Roberston et al. (Eds) 1996, London, Routledge, ISBN 0415 070139, £40.00 hbk

Environmental Policy with Political Integration: the European Union and the United States. New horizons in environmental economics. John B. Braden, Henk Folmer &; Thomas S. Ulen (Eds), 1996, Cheltenham, Elgar Publishing, 477 pp. ISBN 1 85898 217 0