Home About us Contact
|
Home About us Contact | ||
|
|
||
Ties
Kinds of Ties Selected AbstractsWhole sediment toxicity identification evaluation tools for pyrethroid insecticides: III.ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2009Temperature manipulation Abstract Since the toxicity of pyrethroid insecticides is known to increase at low temperatures, the use of temperature manipulation was explored as a whole-sediment toxicity identification evaluation (TIE) tool to help identify sediment samples in which pyrethroid insecticides are responsible for observed toxicity. The amphipod Hyalella azteca is commonly used for toxicity testing of sediments at a 23°C test temperature. However, a temperature reduction to 18°C doubled the toxicity of pyrethroids, and a further reduction to 13°C tripled their toxicity. A similar response, though less dramatic, was found for 1,1-bis(p -chlorophenyl)-2,2,2-trichloroethane (DDT), and dissimilar temperature responses were seen for cadmium and the insecticide chlorpyrifos. Tests with field-collected sediments containing pyrethroids and/or chlorpyrifos showed the expected thermal dependency in nearly all instances. The inverse relationship between temperature and toxicity provides a simple approach to help establish when pyrethroids are the principal toxicant in a sediment sample that could be used as a supplemental tool in concert with chemical analysis or other TIE manipulations. The phenomenon appears to be, in part, a consequence of a reduced ability to biotransform the toxic parent compound at cooler temperatures. The strong dependence of pyrethroid toxicity on temperature has important ramifications for predicting their environmental effects, and the standard test temperature of 23°C dramatically underestimates risk to resident fauna during the cooler months. [source] Development of toxicity identification evaluation procedures for pyrethroid detection using esterase activityENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2004Craig E. Wheelock Abstract Recent agrochemical usage patterns suggest that the use of organophosphate (OP) pesticides will decrease, resulting in a concomitant increase in pyrethroid usage. Pyrethroids are known for their potential toxicity to aquatic invertebrates and many fish species. Current toxicity identification evaluation (TIE) techniques are able to detect OPs, but have not been optimized for pyrethroids. Organophosphate identification methods depend upon the use of piperonyl butoxide (PBO) to identify OP-induced toxicity. However, the use of PBO in TIE assays will be confounded by the co-occurrence of OPs and pyrethroids in receiving waters. It is necessary, therefore, to develop new TIE procedures for pyrethroids. This study evaluated the use of a pyrethroid-specific antibody, PBO, and carboxylesterase activity to identify pyrethroid toxicity in aquatic toxicity testing with Ceriodaphnia dubia. The antibody caused significant mortality to the C. dubia. Piperonyl butoxide synergized pyrethroid-associated toxicity, but this effect may be difficult to interpret in the presence of OPs and pyrethroids. Carboxylesterase activity removed pyrethroid-associated toxicity in a dose-dependent manner and did not compromise OP toxicity, suggesting that carboxylesterase treatment will not interfere with TIE OP detection methods. These results indicate that the addition of carboxylesterase to TIE procedures can be used to detect pyrethroids in aquatic samples. [source] Wastewater treatment polymers identified as the toxic component of a diamond mine effluentENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2004Simone J. C. de Rosemond Abstract The EkatiÔ Diamond Mine, located approximately 300 km northeast of Yellowknife in Canada's Northwest Territories, uses mechanical crushing and washing processes to extract diamonds from kimberlite ore. The processing plant's effluent contains kimberlite ore particles (,0.5 mm), wastewater, and two wastewater treatment polymers, a cationic polydiallydimethylammonium chloride (DADMAC) polymer and an anionic sodium acrylate polyacrylamide (PAM) polymer. A series of acute (48-h) and chronic (7-d) toxicity tests determined the processed kimberlite effluent (PKE) was chronically, but not acutely, toxic to Ceriodaphnia dubia. Reproduction of C. dubia was inhibited significantly at concentrations as low as 12.5% PKE. Toxicity identification evaluations (TIE) were initiated to identify the toxic component of PKE. Ethylenediaminetetraacetic acid (EDTA), sodium thiosulfate, aeration, and solid phase extraction with C-18 manipulations failed to reduce PKE toxicity. Toxicity was reduced significantly by pH adjustments to pH 3 or 11 followed by filtration. Toxicity testing with C. dubia determined that the cationic DADMAC polymer had a 48-h median lethal concentration (LC50) of 0.32 mg/L and 7-d median effective concentration (EC50) of 0.014 mg/L. The anionic PAM polymer had a 48-h LC50 of 218 mg/L. A weight-of-evidence approach, using the data obtained from the TIE, the polymer toxicity experiments, the estimated concentration of the cationic polymer in the kimberlite effluent, and the behavior of kimberlite minerals in pH-adjusted solutions provided sufficient evidence to identify the cationic DADMAC polymer as the toxic component of the diamond mine PKE. [source] Implication of polymer toxicity in a municipal wastewater effluentENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2000Carolyn D. Rowland Abstract The use of cationic polymers as flocculants and coagulant aids to control suspended solid levels in the water and wastewater treatment industry is widespread in most developed countries. Today, the most frequently used clarification polymers, polyacrylamides, are often proprietary, and little information exists on the ecological impacts of these products. Following standard U.S. Environmental Protection Agency (U.S. EPA) whole effluent toxicity testing (WET) protocols, effluent toxicity can be detected via organism response, yet methods to positively characterize cationic polymers in effluents are not provided in U.S. EPA Phase I toxicity identification evaluation (TIE) protocols. Implication of cationic polymer toxicity in a municipal wastewater effluent was achieved through a series of Ceriodaphnia dubia toxicity testing with toxicant elimination steps that included extensive effluent characterization and effluent manipulation. Key in the identification was a discrepancy in effluent toxicity with respect to the type of container in which the effluents were stored. All effluent toxicity was lost within 48 h of storage in plastic containers, while on the contrary, effluent toxicity persisted in glass-contained samples for up to 4 weeks of 4°C storage. A weight-of-evidence approach suggested that the cationic polyacrilamide polymer, Hyperfloc®, was the primary source of acute toxicity in the effluent. Removal of this polymer significantly reduced effluent toxicity. This study suggests that cationic polymer-related toxicity might not be detected if effluent samples are stored in plastic containers. [source] THE EFFECTS OF SOCIAL TIES ON CRIME VARY BY CRIMINAL PROPENSITY: A LIFE-COURSE MODEL OF INTERDEPENDENCE,CRIMINOLOGY, Issue 2 2001BRADLEY R. ENTNER WRIGHT Previous studies have explained the transition from criminal propensity in youth to criminal behavior in adulthood with hypotheses of enduring criminal propensity, unique social causation, and cumulative social disadvantage. In this article we develop an additional hypothesis derived from the life-course concept of interdependence: The effects of social ties on crime vary as a function of individuals' propsensity for crime. We tested these four hypotheses with data from the Dunedin Study. In support of life-course interdependence, prosocial ties, such as education, employment, family ties, and partnerships, deterred crime, and antisocial ties, such as delinquent peers, promoted crime, most strongly among low self-control individuals. Our findings bear implications for theories and policies of crime. [source] BOOK REVIEW DIALOGUE: TIES THAT BINDAMERICAN BUSINESS LAW JOURNAL, Issue 3 2000(Thomas Donaldson, 306 pages), Harvard Business School, Thomas W. Dunfee First page of article [source] THE UNREFLECTIVE BONDS OF INTIMACY: HEGEL ON FAMILIAL TIES AND THE MODERN PERSONPHILOSOPHICAL FORUM, Issue 2 2006DAVID CIAVATTA First page of article [source] REGIONAL TIES AND DISCRIMINATION: POLITICAL CHANGE, ECONOMIC CRISIS, AND JOB DISPLACEMENTS IN SOUTH KOREA, 1997,99THE DEVELOPING ECONOMIES, Issue 1 2007Changhui KANG J71; O53; C25 Probing into the incidence of job displacements during the 1997,99 recession period, this study offers theoretically grounded micro-causal explanations for regional ties and regional discrimination in South Korea. Our statistical analysis reveals the significant impact of a worker's birth region (the basis of regional ties and discrimination) on the layoff process. Native Kyongsang workers are found to have faced higher rates of layoff in Seoul-Kyongki regional firms than native Jolla workers during the recession period. The Kyongsang,Jolla layoff rate gap is mainly due to differential treatment rather than a difference in observable characteristics. The findings suggest that the problem of regional ties and regional discrimination is more deep-rooted and widespread in South Korea than previously reported. [source] GENETIC TIES: ARE THEY MORALLY BINDING?BIOETHICS, Issue 2 2006GIULIANA FUSCALDO ABSTRACT Does genetic relatedness define who is a mother or father and who incurs obligations towards or entitlements over children? While once the answer to this question may have been obvious, advances in reproductive technologies have complicated our understanding of what makes a parent. In a recent publication Bayne and Kolers argue for a pluralistic account of parenthood on the basis that genetic derivation, gestation, extended custody and sometimes intention to parent are sufficient (but not necessary) grounds for parenthood.1 Bayne and Kolers further suggest that definitions of parenthood are underpinned by the assumption that ,being causally implicated in the creation of a child is the key basis for being its parent'.2 This paper examines the claim that genetic relatedness is sufficient grounds for parenthood based on a causal connection between genetic parents and their offspring. I argue that parental obligations are about moral responsibility and not causal responsibility because we are not morally accountable for every consequence to which we causally contribute. My account includes the conditions generally held to apply to moral responsibility, i.e. freedom and foreseeability. I argue that parental responsibilities are generated whenever the birth of a child is a reasonably foreseeable consequence of voluntary actions. I consider the implications of this account for third parties involved in reproductive technologies. I argue that under some conditions the obligations generated by freely and foreseeably causing a child to exist can be justifiably transferred to others. [source] Application of toxicity identification evaluation procedures for characterizing produced water using the tropical mysid, Metamysidopsis insularisENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2004Najila Elias-Samlalsingh Abstract Toxicity identification evaluations (TIEs) were performed on seven produced water (PW) effluents from inland discharge facilities operated in Trinidad and Tobago, a Caribbean tropical country with one of the oldest commercial oil industries in the world. The research was performed to determine the presence and magnitude of toxicity and characterize which toxicants are responsible for observed effects. Marine effluent toxicity characterizations with Metamysidopsis insularis revealed high whole acute toxic-unit response for produced water ranged from 8.1 to >17.0 acute toxic-unit (initial toxicity test) and 5.7 to 1,111 acute toxic-unit (baseline toxicity test). Toxicity test results for all sites except one, which had the highest toxicity, are comparative with similar studies on produced water. The toxicological causality of this complex mixture differed for each PW with nonpolar organics being consistently toxic in all samples. Other potential toxicants contributing to overall toxicity to a much lesser extent were metals, ammonia, and volatile organic compounds. With the use of sodium thiosulfate and filtration manipulations for only PW6 sample, there was very slight reduction in toxicity; therefore, oxidants and filterable materials were not a great contributing factor. Whole effluent toxicity also can be attributed to ionic imbalance and the very stable oil-in-water emulsion that consists of fine oil droplets (less than 0.1,10 ,m with an average diameter of 2.5 ,m). This investigation is the first of its type in Trinidad and demonstrates clearly the applicability of this test method and local test species for evaluating complex effluents in tropical environments. [source] Ecotoxicologic impacts of agricultural drain water in the Salinas River, California, USAENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2003Brian S. Anderson Abstract The Salinas River is the largest of the three rivers that drain into the Monterey Bay National Marine Sanctuary in central California (USA). Large areas of this watershed are cultivated year-round in row crops, and previous laboratory studies have demonstrated that acute toxicity of agricultural drain water to Ceriodaphnia dubia is caused by the organophosphate (OP) pesticides chlorpyrifos and diazinon. We investigated chemical contamination and toxicity in waters and sediments in the river downstream of an agricultural drain water input. Ecological impacts of drain water were investigated by using bioassessments of macroinvertebrate community structure. Toxicity identification evaluations were used to characterize chemicals responsible for toxicity. Salinas River water downstream of the agricultural drain was acutely toxic to the cladoceran Ceriodaphnia dubia, and toxicity to C. dubia was highly correlated with combined toxic units (TUs) of chlorpyrifos and diazinon. Laboratory tests were used to demonstrate that sediments in this system were acutely toxic to the amphipod Hyalella azteca, a resident invertebrate. Toxicity identification evaluations (TIEs) conducted on sediment pore water suggested that toxicity to amphipods was due in part to OP pesticides; concentrations of chlorpyrifos in pore water sometimes exceeded the 10-d mean lethal concentration (LC50) for H. azteca. Potentiation of toxicity with addition of the metabolic inhibitor piperonyl butoxide suggested that sediment toxicity also was due to other non,metabolically activated compounds. Macroinvertebrate community structure was highly impacted downstream of the agricultural drain input, and a number of macroinvertebrate community metrics were negatively correlated with combined TUs of chlorpyrifos and diazinon, as well as turbidity associated with the drain water. Some macroinvertebrate metrics were also correlated with bank vegetation cover. This study suggests that pesticide pollution is the likely cause of ecological damage in the Salinas River, and this factor may interact with other stressors associated with agricultural drain water to impact the macroinvertebrate community in the system. [source] Potentiation of angiogenic response by ischemic and hypoxic reconditioning of the heartJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 1 2002Nilanjana Maulik Abstract This review is intended to discuss the newly discovered role of preconditioning which should make it an attractive therapeutic stimulus for repairing the injured myocardium. We recently found that apart from rendering the myocardium tolerant to ischemic reperfusion injury, preconditioning also potentiates angiogenesis. Our study demonstrated for the first time that both ischemic and hypoxic preconditioning triggered myocardial angiogenesis at the capillary and arteriolar levels which nicely corroborated with the improved myocardial contractile function.Hypoxic preconditioning resulted in the stimulation of VEGF, the most potent angiogenic factor known to date. In concert, endothelial cell specific tyrosine kinase receptors, Tie 1, Tie 2 and Flt-1 and Flk-1 were also significantly enhanced in the preconditioned myocardium. The redox-regulated transcription factor NFkB was found to play an essential role in the preconditioning regulation of angiogenesis [source] Book review: Fit to be Tied: Sterilization and Reproductive Rights in America, 1950,1980AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2010Michael A. Rembis No abstract is available for this article. [source] The Effect of Network Ties on Accounting Controls in a Supply Alliance: Field Study Evidence,CONTEMPORARY ACCOUNTING RESEARCH, Issue 1 2007Wai Fong Chua First page of article [source] State Policy, Economic Crisis, Gender, and Family Ties: Determinants of Family Remittances to CubaECONOMIC GEOGRAPHY, Issue 1 2004Sarah A. Blue Abstract: This article advances the argument that changing economic conditions in the home country act as an important determinant for sending remittances. Research on the determinants of remittances has tended to focus on the characteristics of the sending population. In the case of Cuba, disproportionate attention is paid to political disincentives to send remittances and not enough to changing state policy and the growing economic demand for remittances in that country. Using empirical data gathered from households in Havana, this article tests the importance of economic conditions in the home country, political ideology, the relationship of the sender to the receiver, the length of time away from home, and gender as determinants for remittances. Migration during an economic crisis, having immediate relatives in the home country, and female gender positively influenced remittance behavior for Cuban emigrants. Visits to the home country, especially for migrants who had left decades earlier, were found to be critical for reestablishing family connections and increasing remittances. No support was found for political disincentives as a major determinant of remittance sending to Cuba. [source] Transnational Ties, Poverty, and Identity: Latin American Immigrant Women in Public Housing,FAMILY RELATIONS, Issue 4 2008Silvia Domínguez Abstract: This study used ethnographic data to examine the nature and functions of transnational relationships of low-income Latin American women who had immigrated to the United States and were living in areas of extreme poverty. Findings indicated that these Latin American mothers utilized transnational ties to help maintain the cultural identities of themselves and their children, to alleviate social isolation, and to provide a safer summer housing alternative for their children. Transnational ties may have had some negative consequences, including financial and social burdens associated with maintaining long-distance familial relationships. However, despite some negative aspects, we conclude that transnational ties are often an instrumental resource for immigrant mothers living in poverty and are vital to immigrant social mobility. [source] Expatriate Social Ties: Personality Antecedents and Consequences for AdjustmentINTERNATIONAL JOURNAL OF SELECTION AND ASSESSMENT, Issue 4 2003Erin C. Johnson This expaloratory study examines the relationship between personality characteristics (extraversion, core self evaluations), social tie characteristics (number, breadth, depth), and three types of expatriate adjustment (general, interaction, and work). Data was collected at two points in time from 75 expatriate employees from one organization on international assignments around the world. Results indicate that core self-evaluations, but not extraversion, are positively related to the number of ties formed with other expatriates and host country nationals. Social ties with other expatriates were found to provide greater social support, but similar access to information, than those with host country nationals (HCNs). In general, depth and breadth of relationships with other expatriates predicted general and work adjustment; whereas, breadth and total number of relationships with HCNs predicted all three types of adjustment. Overall, these results provide initial support for the importance of social ties in facilitating expatriate adjustment. [source] SOUTH AFRICA,INDIA: Visiting President Calls for Stronger TiesAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 5 2010Article first published online: 8 JUL 2010 No abstract is available for this article. [source] DR CONGO , UGANDA: Ties BoostedAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 2 2009Article first published online: 7 APR 200 No abstract is available for this article. [source] Online Communication and Adolescent Social Ties: Who benefits more from Internet use?,JOURNAL OF COMPUTER-MEDIATED COMMUNICATION, Issue 3 2009Sook Jung Lee Literature suggests 4 hypotheses to explain social outcomes of online communication among adolescents: displacement, increase, rich-get-richer, and social-compensation hypotheses. The present study examines which hypothesis is supported, considering differences in social ties (time vs. quality of social relationships; parent-child relationships; friendships; school connectedness). This study's sample was 1,312 adolescents ages 12 to 18. Displacement hypothesis predicted negative associations between time in online communication and time with parents, but time with friends was not displaced. Examination of relationships among earlier sociability, online communication, and cohesive friendships supported the rich-get-richer hypothesis. That is, adolescents who already had strong social relationships at earlier ages were more likely to use online communication, which in turn predicted more cohesive friendships and better connectedness to school. [source] Presbyterian Social Ties and Mobility in the Irish Sea Culture Area, 1610,1690JOURNAL OF HISTORICAL SOCIOLOGY, Issue 3 2005BARRY VANN Moreover, few studies have considered the reverse flow of ministers to Scotland from Ireland and how their experiences in Ulster (the nine northern-most counties in Ireland) impacted the political landscape in south-western Scotland. This study addresses those voids in the literature. [source] Examining the Conditional Limits of Relational Governance: Specialized Assets, Performance Ambiguity, and Long-Standing TiesJOURNAL OF MANAGEMENT STUDIES, Issue 7 2008Laura Poppo abstract Despite recognition of the benefits of relational governance in inter-organizational exchanges, factors that may erode its value have received little examination. We extend the literature by asking whether self-interested opportunities and long-standing ties erode the positive association between relational governance and performance. Consistent with transaction cost and moral hazard logics, exchange hazards, particularly asset specificity and difficult performance measurement, dampen the positive association of relational governance and performance. We further find, consistent with recent inquiries into the dark side of embedded ties that the performance benefits associated with relational governance decline when parties rely on repeated partnerships. [source] Stepfamily Formation: Implications for Adolescent Ties to Mothers, Nonresident Fathers, and StepfathersJOURNAL OF MARRIAGE AND FAMILY, Issue 4 2009Valarie King This study examines how the entrance of a stepfather influences adolescent ties to mothers and nonresident fathers and how prior ties to each biological parent influence the development of stepfather-stepchild ties. Data come from 1,753 adolescents in the National Longitudinal Study of Adolescent Health who lived with a single mother in Wave 1 who remained single, cohabited, or married by Wave 2, approximately 1 year later. Stepfamily formation had little consequence for adolescent-nonresident father ties. Adolescent-mother closeness, however, declined when cohabiting, but not married, stepfathers entered the household. Close ties to married stepfathers were more likely to develop when adolescents were closer to their mothers before stepfather entry. Prior ties to nonresident fathers were unrelated to stepfather-stepchild ties. [source] Sociological Ambivalence and Family Ties: A Critical PerspectiveJOURNAL OF MARRIAGE AND FAMILY, Issue 3 2002Ingrid Arnet Connidis We develop the concept of ambivalence as structurally created contradictions that are made manifest in interaction. We discuss how our reconceptualization enhances the relevance of ambivalence to sociological analyses of family ties. Ambivalence is a particularly useful concept when imbedded in a theoretical framework that views social structure as structured social relations, and individuals as actors who exercise agency as they negotiate relationships within the constraints of social structure. The strengths of conceptualizing ambivalence within this framework are illustrated with examples of caring for older family members and of balancing paid work and family responsibilities. [source] The Role of Family Ties in the Labour Market.LABOUR, Issue 4 2001An Interpretation Based on Efficiency Wage Theory By casual empiricism, it seems that many firms take explicit account of the family ties connecting workers, often hiring individuals belonging to the same family or passing jobs on from parents to their children. This paper makes an attempt to explain this behaviour by introducing the assumption of altruism within the family and supposing that agents maximize a family utility function rather than an individual one. This hypothesis has been almost ignored in the analysis of the relationship between employers and employees. The implications of this assumption in the efficiency wage models are explored: by employing members of the same family, firms can use a (credible) harsher threat , involving a sanction for all the family's members in case of one member's shirking , that allows them to pay a lower efficiency wage. On the other hand, workers who accept this agreement exchange a reduction in wage with an increase in their probability of being employed: this can be optimal in a situation of high unemployment. Moreover, the link between parents and children allows the firm to follow a strategy that solves the problem of an individual's finite time horizon by its making use of the family's reputation. [source] New Tech, New Ties: How Mobile Communication is Reshaping Social Cohesion by Richard Seyler LingMUSEUM ANTHROPOLOGY, Issue 2 2009HEATHER A. HORST [source] Impact to Spinal Cord Stimulator Lead Integrity with Direct Suture Loop Ties: Commentary on Kreis et al. (2009)PAIN MEDICINE, Issue 7 2010Michael Colvin PhD No abstract is available for this article. [source] In Search of a Balanced Relationship: China, Latin America, and the United StatesASIAN POLITICS AND POLICY, Issue 1 2009William Ratliff This study focuses on the four stages of Chinese relations with Latin America between 1949 and mid-2008. Ties during the 1950s were limited but directed toward a broad cross-section of individual Latin Americans. This was abruptly reversed during the Sino-Soviet dispute of the 1960s by militant advocacy of guerrilla warfare in Latin America. From the early 1970s until the death of Mao Zedong, militant Maoism was blended with a renewed opening of relations, now to military and civilian Latin governments. The final period began with Deng Xiaoping and his reforms and continues to today. This study focuses on Sino-Latin political and economic relations in general and links to the radical governments of Cuba and Venezuela in particular and weighs the impact of this expansion on Sino-U.S. relations. It concludes with comments on how China's presence may affect political and economic developments in Latin America itself and how to hone productive cooperation among China, the United States, and Latin nations. [source] Family Ties: The Political Genealogy of Shining Path's Comrade NorahBULLETIN OF LATIN AMERICAN RESEARCH, Issue 2 2010JAYMIE PATRICIA HEILMAN Family was central to the political life of Augusta La Torre (or Comrade Norah), the second-in-command of the Peruvian Communist Party-Shining Path (PCP-SL). La Torre was the daughter of a Communist Party militant and the granddaughter of a prominent provincial political figure. She was also the wife of Shining Path founder Abimael Guzmán. La Torre's familial history demonstrates the importance of parental and grandparental contributions to Senderistas' political formation, and suggests that parents and children were sometimes united in their support for the Shining Path. La Torre's family ties, however, have also led numerous observers to question her revolutionary credentials. [source] Ties that Bind: ISCT As a Procedural Approach to Business EthicsBUSINESS AND SOCIETY REVIEW, Issue 4 2000Steven R. Salbu [source] | |||||||||||||||||||||||||||||||||||||||||||||||||