Massachusetts

Distribution by Scientific Domains

Terms modified by Massachusetts

  • massachusetts general hospital
  • massachusetts institute

  • Selected Abstracts


    Siggraph 2006 Boston, Massachusetts, 30th July,3rd August 2006

    COMPUTER GRAPHICS FORUM, Issue 1 2007
    R.G. Laycock
    No abstract is available for this article. [source]


    Assessing the Risk of Introducing Exotic Species via the Live Marine Species Trade

    CONSERVATION BIOLOGY, Issue 1 2005
    SHANNON M. WEIGLE
    especies estuarinas; introducción de especies; mecanismos de transferencia de especies invasoras; prevención de especies invasoras; riesgo de invasiones Abstract:,Although the shipping industry has received considerable attention as a dispersal mechanism for aquatic nuisance species, many invasions have been linked to other mechanisms of transfer. The threat posed to coastal ecosystems by these alternative mechanisms, however, remains largely unquantified. We assessed the potential risks of introducing marine and estuarine species associated with seven mechanisms of transfer: seafood companies, aquaculture operations, bait shops, stores that sell marine ornamental species, research and educational organizations, public aquariums, and coastal restoration projects. For each, we compiled a comprehensive database of organizations in coastal Massachusetts. We then designed and administered a survey to a subset of organizations that inquired about (1) their proximity to saltwater and methods of handling live imports; (2) the type and quantity of marine species being imported; and (3) the organization's familiarity with marine invasions. Respondents in five of the seven categories acknowledged importing nonlocal live marine species to the area. Seafood companies handled the majority of individuals but relatively few taxa. This mechanism of transfer also had the most complex trade patterns and the greatest number of operations located near saltwater. In contrast, the other transfer mechanisms each had simpler trade pathways and fewer operations but varied in the quantity and taxonomic diversity of their imports. Significantly, no single mechanism of transfer stood out as presenting a primary risk. Rather, each had characteristics or used handling practices at different points in the importation process that could facilitate introductions. To prevent future marine invasions, better reporting requirements for live species imports are needed, and best-management practices and outreach strategies specific to the transfer mechanism should be developed and implemented. Resumen:,Aunque la industria de transportación marítima ha recibido considerable atención como un mecanismo de dispersión de especies acuáticas molestas, muchas invasiones han sido relacionadas con otros mecanismos de transferencia. Sin embargo, la amenaza de estos mecanismos alternativos a los ecosistemas costeros permanece en gran parte sin cuantificar. Evaluamos los potenciales riesgos para especies marinas y estuarinas asociados con siete mecanismos de transferencia: compañías de mariscos, operaciones acuaculturales, tiendas de especies marinas ornamentales, organizaciones de investigación y educativas, acuarios públicos y proyectos de restauración costera. Para cada uno, compilamos una amplia base de datos de organizaciones en la costa de Massachussetts. Luego diseñamos y aplicamos una encuesta a un subconjunto de organizaciones para obtener información sobre (1) su proximidad al agua marina y sus métodos para el manejo de importaciones vivas, (2) el tipo y cantidad de especies marinas importadas y (3) la familiaridad de la organización con invasiones marinas. Evaluamos los potenciales riesgos de introducciones de especies marinas y estuarinas. Los encuestados en cinco de siete categorías reconocieron importar especies marinas vivas no locales al área. Las compañías de mariscos manejaron a la mayoría de los individuos pero relativamente pocos taxa. Este mecanismo de transferencia también tuvo los patrones comerciales más complejos y el mayor número de operaciones localizadas cerca de agua marina. En contraste, cada uno de los demás mecanismos de transferencia tuvo canales de comercialización más simples y menos operaciones, pero variaron en la cantidad y diversidad taxonómica de sus importaciones. Significativamente, ningún mecanismo individual resaltó como un riesgo primario. Más bien, cada uno tenía características o utilizaba prácticas de manejo en diferentes etapas del proceso de importación que podían facilitar las introducciones. Para prevenir futuras invasiones marinas, se necesitan mejores requerimientos para reportar la importación de especies vivas, y se deben desarrollar e implementar prácticas de manejo óptimo y estrategias de extensión específicas para el mecanismo de transferencia. [source]


    Combining Strategies to Select Reserves in Fragmented Landscapes

    CONSERVATION BIOLOGY, Issue 4 2004
    KRISTINA D. ROTHLEY
    These criteria are assumed to be reasonable surrogates for the true network objectives. Caution is warranted, however, because the relationships between the selection criteria and the reserve-network objectives may be inconsistent. Conflicts are also likely to arise because no single reserve network will be optimal with respect to multiple objectives (or selection criteria) simultaneously. Instead, reserve planners must compromise between conflicting demands. We field tested the relationships between a variety of selection criteria and the objectives of a reserve network for the sandplain natural communities on Martha's Vineyard Island, Massachusetts (U.S.A.). Selection criteria that correlated with the reserve-network objectives were used in a multi-objective integer program to identify the 10-patch reserve networks that were optimal with each objective independently and those that offered optimal tradeoffs between the reserve-network objectives. From these 10-patch networks, one can select a final reserve network that provides the preferred compromise between the objectives. Resumen:,La utilización de criterios de selección, como el tamaño de parche, para clasificar el valor de conservación de los parches de hábitat y evaluar redes de reservas alternativas es un método para identificar redes de reservas en paisajes fragmentados con datos especie-específicos limitados,. Se asume que estos criterios son sustitutos razonables de los verdaderos objetivos de la red. Sin embargo, se requiere cuidado porque las relaciones entre los criterios de selección y los objetivos de la red de reservas pueden ser inconsistentes. Es probable que surjan conflictos porque ninguna red de reservas seráóptima con respecto a objetivos (o criterios de selección) múltiples simultáneamente. Más bien, los planificadores de reservas deben transigir entre demandas conflictivas. Probamos las relaciones entre una variedad de criterios de selección y los objetivos de una red de reservas para comunidades arenícolas naturales en la Isla Martha's Vineyard, Massachussets (E.U.A.). Los criterios de selección que se correlacionaron con los objetivos de la red de reservas fueron utilizados en un programa multi-objetivo integral para identificar las 10 redes de reservas de fragmentos óptimas con cada objetivo independientemente y las que ofrecían compensaciones óptimas entre los objetivos de la red de reservas. De estas 10 redes de reservas de fragmentos, se puede seleccionar una red de reservas final que proporcione el compromiso preferido entre los objetivos. [source]


    Estimate of the Area Affected Ecologically by the Road System in the United States

    CONSERVATION BIOLOGY, Issue 1 2000
    Richard T. T. Forman
    Two recent studies in The Netherlands and Massachusetts ( U.S.A.) evaluated several ecological effects of roads, including traffic noise effects, and provide quantitative evidence for a definable "road-effect zone." Based on the approximate width of this asymmetric convoluted zone, I estimate that about one-fifth of the U.S. land area is directly affected ecologically by the system of public roads. I identify a series of assumptions and variables suggesting that over time this preliminary estimate is more likely to rise than drop. Several transportation planning and policy recommendations, ranging from perforating the road barrier for wildlife crossings to closing certain roads, offer promise for reducing this enormous ecological effect. Resumen: En vista de un sistema carretero extensivo, un abundante y creciente tráfico vehicular y una literatura dispersa indicando que algunos efectos ecológicos de las carreteras se extienden más allá de 100 m, parece probable que los efectos ecológicos acumulativos del sistema carretero en los Estados Unidos es considerable. Dos estudios recientes en los Países Bajos y Massachusetts ( USA) evaluaron diversos efectos ecológicos de las carreteras, incluyendo efectos del ruido del tráfico y proporcionan evidencia cuantitativa para una definible "zona de efecto carretero". En base a la amplitud aproximada de esta zona conpleja y asimétrica, estimé que alrededor de una auinta parte del área terrestre de los Estados Unidos es directamente afectada ecológicamente por el sistema de carreteras públicas. Identifiqué series de conjeturas y variables que surgieren que a lo largo del tiempo esta estimación preliminar es mas probable que incremente a que disminuya. Diversos planes de transportación y recomendaciones políticas, que van desde perforar la barrera carretera para propiciar el cruce de vida silvestre hasta el cierre de ciertas carreteras ofrecen la promesa de reducir este efecto carretero. [source]


    POLICING CRIME AND DISORDER HOT SPOTS: A RANDOMIZED CONTROLLED TRIAL,

    CRIMINOLOGY, Issue 3 2008
    ANTHONY A. BRAGA
    Dealing with physical and social disorder to prevent serious crime has become a central strategy for policing. This study evaluates the effects of policing disorder, within a problem-oriented policing framework, at crime and disorder hot spots in Lowell, Massachusetts. Thirty-four hot spots were matched into 17 pairs, and one member of each pair was allocated to treatment conditions in a randomized block field experiment. The officers engaged "shallow" problem solving and implemented a strategy that more closely resembled a general policing disorder strategy rather than carefully designed problem-oriented policing responses. Nevertheless, the impact evaluation revealed significant reductions in crime and disorder calls for service, and systematic observations of social and physical disorder at the treatment places relative to the control places uncovered no evidence of significant crime displacement. A mediation analysis of the isolated and exhaustive causal mechanisms that comprised the strategy revealed that the strongest crime-prevention gains were generated by situational prevention strategies rather than by misdemeanor arrests or social service strategies. [source]


    Winter energetics of Virginia opossums Didelphis virginiana and implications for the species' northern distributional limit

    ECOGRAPHY, Issue 6 2005
    L. Leann KandaArticle first published online: 27 SEP 200
    While climatic limitations are widely recognized as primary factors determining the distributions of many species, the physiological link between climate and species' persistence is poorly understood. The Virginia opossum Didelphis virginiana is a species for which winter energetics have been evaluated and a northern geographical limit has been hypothesized. Expansion of opossum populations beyond this limit, however, suggests that a previous winter energetics model requires modification. I update this energetics model by incorporating random foraging success to estimate the probability of opossum survival under varying winter temperature regimes. Estimation of opossum "success" for winters in Amherst, Massachusetts, since 1926 showed that juvenile females, the key breeding component of the population, would survive at a rate high enough to maintain a stable population in only 4 of the 77 yr. The model correctly predicted the fate of 13 of 14 opossums monitored in the Amherst area during the winters of 2000,2003. The current energetics model does not correctly predict autumn weight gain, but it does accurately estimate opossum winter survival. However, the model predicts that opossums should be winter-limited in areas such as Amherst, Massachusetts, where in fact they are well established. This discrepancy may be explained in three ways: weather station data do not adequately reflect available microclimates, opossums show high levels of flexibility in cold-weather foraging behavior, and most likely, humans provide food and shelter that mitigate the effect of winter. [source]


    Dietary exposure of mink (Mustela vison) to fish from the Housatonic River, Berkshire County, Massachusetts, USA: Effects on reproduction, kit growth, and survival

    ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2006
    Steven J. Bursian
    Abstract We evaluated the effects of feeding farm-raised mink (Mustela vison) diets containing polychlorinated biphenyl (PCB)-contaminated fish from the Housatonic River (HR; Berkshire County, MA, USA) on adult reproductive performance and kit growth and survival. Diets contained 0.22,3.54% HR fish, providing 0.34,3.7 ,g total PCBs (TPCB)/g feed wet wt (3.5,68.5 pg toxic equivalence [TEQ]/g). Female mink were fed diets before breeding through weaning of kits. Twelve kits from each treatment were maintained on their respective diets for an additional 180 d. Dietary PCBs had no effect on the number of offspring produced, gestation period, or other measures of adult reproductive performance. Mink kits exposed to 3.7 ,g TPCB/g feed (68.5 pg TEQ/g) in utero and during lactation had reduced survivability between three and six weeks of age. The lethal concentrations to 10 and 20% of the population (LC10 and LC20, respectively) were estimated to be 0.231 and 0.984 ,g TPCB/g feed, respectively. Because inclusion of PCB-contaminated fish that composed approximately 1% of the diet would reduce mink kit survival by 20% or more, it is likely that consumption of up to 30-fold that quantity of HR fish, as could be expected for wild mink, would have an adverse effect on wild mink populations. [source]


    In situ reproduction, abundance, and growth of young-of-year and adult largemouth bass in a population exposed to polychlorinated biphenyls

    ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2004
    Dudley W. Reiser
    Abstract We conducted a two-year field study (2000,2001) in the Housatonic River, Massachusetts (USA) to determine if we could detect in situ population-level effects on largemouth bass (Micropterus salmoides) exposed to elevated levels of polychlorinated biphenyls (PCBs). Calculated whole-body PCB concentrations in adult bass in 2002 averaged 121 mg/kg (range = 34,556 mg/kg). Polychlorinated biphenyl concentrations in young-of-year (YOY) composites in 2000 and 2002 averaged 28 mg/kg (range = 21,41 mg/kg) and 19 mg/kg (range = 16,24 mg/kg), respectively. Laboratory studies of fish have reported PCB toxicity at exposure levels below and within the range of those found in the Housatonic River. We evaluated five field-derived metrics: reproductive activity, relative abundance of YOY, YOY growth rates, adult growth, and adult condition to determine whether we could detect effects of PCBs in the largemouth bass population. These computed metrics, when compared with data sets assembled for numerous largemouth bass populations in North America, provided no evidence of population-level impairment. Results of this study suggest that PCB tissue concentrations associated with effects in laboratory studies do not necessarily translate to detectable effects on largemouth bass populations in their natural environment. [source]


    Productivity of American robins exposed to polychlorinated biphenyls, Housatonic River, Massachusetts, USA

    ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2003
    Miranda H. Henning
    Abstract American robins (Turdus migratorius) breeding in the Housatonic River (MA, USA) watershed were studied in the field in 2001 to determine whether productivity was adversely affected by exposure to polychlorinated biphenyls (PCBs), as would be suggested by extrapolation from laboratory studies on other avian species. The study involved identifying nests within the Housatonic River floodplain (target area) and in reference areas beyond foraging distance of the floodplain, monitoring clutch size and number hatched and fledged, collecting eggs and nestlings for analysis for PCBs, and testing for differences in productivity between populations. One hundred and six active robin nests were monitored. Although concentrations of PCBs in target specimens were more than two orders of magnitude greater than in reference specimens, the only statistically significant differences in productivity were inconsistent with an exposure-related effect. First-generation productivity of exposed robins was within the range of natural background variation. Bioequivalence tests confirmed that first-generation productivity was statistically and biologically equivalent in target and reference robins. These findings contrast with extrapolations from laboratory studies of other avian species. [source]


    General Anesthesia and the Ketogenic Diet: Clinical Experience in Nine Patients

    EPILEPSIA, Issue 5 2002
    Ignacio Valencia
    Summary: ,Purpose: To determine if children actively on the ketogenic diet (KD) can safely undergo general anesthesia (GA) for surgical procedures. Methods: The records of children treated with the KD at Children's Hospital (Boston, Massachusetts) from 1995 to the present were reviewed. The charts of children who had received GA while on the diet were evaluated with regard to demographics, procedure information, anesthesia records, blood chemistries, and perioperative course. Of 71 children on the KD during the period of the study, nine (12.7%) had procedures requiring GA while on the diet. Results: Nine children received GA for surgical procedures ranging from central line placement to hemispherectomy while on the KD. At the time of GA, the children ranged from age 1 to 6 years, and had been on the KD for 2,60 months. The patients received carbohydrate-free intravenous solutions perioperatively. Anesthesia duration ranged from 20 min to 11.5 h; for longer procedures, serum pH, glucose, and electrolyte levels were monitored. Serum glucose levels remained stable in all patients, but serum pH typically decreased; the largest reduction was to 7.16. In three procedures, patients received intravenous bicarbonate because of level of acidosis. There were no perioperative complications. Conclusions: Children on the KD can safely undergo GA for surgical procedures. Although serum glucose levels appear to remain stable, serum pH or bicarbonate levels should be monitored because of the risk of metabolic acidosis. [source]


    Anabolic steroid users' attitudes towards physicians

    ADDICTION, Issue 9 2004
    Harrison G. Pope
    ABSTRACT Aims To assess anabolic-androgenic steroid (AAS) users' trust in the knowledge and advice of physicians. Design Interviews of AAS users and non-users. Setting Research offices. Participants Eighty weight-lifters (43 AAS users, 37 non-users) recruited by advertisement in Massachusetts and Florida, USA. Measurements Personal interviews and questionnaire responses, including subjects' ratings of physicians' knowledge regarding various health- and drug-related topics. AAS users also rated their level of trust in various sources of information about AAS. Findings Both groups of subjects gave physicians high ratings on knowledge about general health, cigarette smoking, alcohol, and conventional illicit drugs, but gave physicians markedly and significantly lower ratings on knowledge about AAS. When rating sources of information on AAS, users scored physicians as no more reliable than their friends, Internet sites, or the person(s) who sold them the steroids. Forty percent of users trusted information on AAS from their drug dealers at least as much as information from any physician that they had seen, and 56% had never revealed their AAS use to any physician. Conclusion AAS users show little trust in physicians' knowledge about AAS, and often do not disclose their AAS use to physicians. These attitudes compromise physicians' ability to educate or treat AAS users. Physicians can respond to these problems by learning more about AAS and by maintaining a high index of suspicion when evaluating athletic male patients. [source]


    The cigar as a drug delivery device: youth use of blunts

    ADDICTION, Issue 10 2003
    Stephen Soldz
    ABSTRACT Aims, Blunts are hollowed-out cigars used to smoke marijuana (and perhaps other substances) in the United States. We investigated rates of blunt use; whether cigar use reported in surveys may actually be blunt use; the relationship of blunt to cigar use; characteristics of blunt users; brands of cigars used to make blunts; and drugs added to blunts. Design, A school-based survey of youth, the Cigar Use Reasons Evaluation (CURE). Setting, Eleven schools across Massachusetts. Participants, A total of 5016 students in grades 7,12. Measurements, CURE items assessing blunt, cigar and cigarette use, brands used to make blunts, drugs added to blunts and demographics were used. Findings, Life-time blunt use was reported by 20.0% of the sample, with use greater among high school (25.6%) than middle school (11.4%) students, and among males (23.7%) than females (16.6%). Self-reported cigar use rates were not influenced strongly by blunt use being misreported as cigar use. In a multivariate model, blunt use was associated with male gender, higher grade in school, lower GPA, truancy, lower school attachment, not living in a two-parent family, being of ,other' race/ethnicity and current use of both cigarettes and cigars. ,Phillies' was the most popular brand of cigar for making blunts, used by 59.$% of users. ,Garcia y Vega' (18.0%) was the second most popular. Twenty-eight per cent of blunt users had added drugs other than marijuana to blunts. Conclusions, The use of blunts as a drug delivery device is a serious problem. Efforts to address it will require the cooperation of the tobacco control and substance abuse prevention systems. [source]


    TURNING OFFENDERS INTO RESPONSIBLE PARENTS AND CHILD SUPPORT PAYERS,

    FAMILY COURT REVIEW, Issue 3 2005
    Esther Ann Griswold
    This article describes four demonstration projects that strive to promote responsible behavior with respect to parenting, child support payment, and employment among incarcerated and paroled parents with child support obligations. These projects, conducted in Colorado, Illinois, Massachusetts, and Texas, with support from the federal Office of Child Support Enforcement and evaluated by the Center for Policy Research, led to a number of common outcomes and lessons. The projects revealed that inmates want help with child support, parenting, and employment and that prisons can be effective settings in which to conduct such interventions. Family reintegration programs were popular with inmates and may have helped to avoid the rupture of parent,child relationships commonly associated with incarceration. Although employment is the key to child support payment following release, rates of postrelease employment and earnings at all project sites were low and the employment programs were of limited utility in helping released offenders find jobs. Agencies dealing with child support, employment, and criminal justice need to adopt more effective policies with incarcerated parents including transitional job programs that guarantee immediate, subsidized employment upon release, child support guidelines that adjust for low earnings, and better training and education opportunities during incarceration. [source]


    Brook trout, Salvelinus fontinalis, microhabitat selection and diet under low summer stream flows

    FISHERIES MANAGEMENT & ECOLOGY, Issue 3 2006
    J. C. SOTIROPOULOS
    Abstract, This study investigated the effects of low summer discharge on habitat, prey use and prey availability for age 1 brook trout, Salvelinus fontinalis (Mitchill), in two small streams in Massachusetts, USA. Stream discharge declined substantially from June to August, with corresponding decreases in microhabitat depth and velocity; but fish habitat preferences were consistent throughout the summer, with fish selecting deep, low current velocity locations. Invertebrate drift rate, drift density and trout stomach fullness were significantly greater in June than August samples. Diets were dominated by aquatic-derived prey (chironomid larvae and adult blackflies) in June, but terrestrial invertebrates were the most frequent diet items in August. Consistent occupancy of low-velocity, deep microhabitats with low invertebrate flux rates indicated that, despite variation in habitat and prey conditions, trout adopted a habitat-use strategy of minimising risks and energy costs rather than maximising forage gain. This observation is consistent with, and provides a potential explanation for, the low summer growth rates of brook trout observed in small streams. [source]


    Use of tag data to compare growth rates of Atlantic coast striped bass stocks

    FISHERIES MANAGEMENT & ECOLOGY, Issue 5 2003
    S. A. Welsh
    Abstract Migratory stocks of Atlantic coast striped bass, Morone saxatilis (Walbaum), range primarily from North Carolina (NC) northward to Canadian waters. Between 1986 and 2000, 267 045 wild striped bass were tagged and released from NC to Massachusetts as part of the Cooperative Striped Bass Tagging Program. Direct measurements of growth of individual fish can be obtained from tag data and are useful for understanding the dynamics of fish populations. Growth rates from regressions of length-increment vs. time-at-liberty were estimated for striped bass tagged and released in three southern states [NC, Virginia (VA) and Maryland (MD)] and three northern states (New Jersey, New York and Rhode Island). Striped bass tagged in waters of northern states grew faster (significantly steeper regression slopes) than those tagged in southern areas. Migratory patterns, stock mixing, and unmeasured biotic and abiotic influences on growth precluded conclusions that observed growth patterns are stock-specific. These results, however, indicate latitudinal differences in growth rates, and should be considered in future research and management of Atlantic coast striped bass. [source]


    Thermal habitat of striped bass (Morone saxatilis) in coastal waters of northern Massachusetts, USA, during summer

    FISHERIES OCEANOGRAPHY, Issue 5 2010
    GARY A. NELSON
    Abstract Striped bass, Morone saxatilis, were captured and released with temperature-measuring data storage tags in Salem Sound, Massachusetts, to collect data on their thermal preferences in coastal and marine waters and to identify environmental factors that may influence temperatures experienced during their summer residence. Striped bass recaptured during summer of 2006 (21 of 151 releases) experienced a wide range of temperatures (6.5,28.0°C) while at-large for 1,53 days. Overall mean temperature and standard deviation selected by striped bass recaptured in Salem Sound during the longest commonly-shared duration of time (3,12 July) were 17.8 and 3.57°C, respectively. Comparison of temperature data between fish and 13 vertical arrays in Salem Sound revealed that striped bass experienced higher and more variable temperatures, and that daily changes in temperature actually experienced were unrelated to daily changes in surrounding ambient temperature. Regular cyclical changes in temperature of all striped bass and vertical arrays were identified as influences of the local tide, which contributed about a 2°C change in temperature, on average, over the complete cycle. Most striped bass appeared to limit their activities to depths shallower than the lower limit of the thermocline, above which temperatures generally exceed 9.0°C in Salem Sound. Therefore, it is likely that the vertical distribution of striped bass is restricted by the low temperatures below this depth. An implication of this finding is that the spatial distribution of striped bass may be defined coarsely by knowledge of the distribution of temperature in coastal areas. [source]


    Larval lobster (Homarus americanus) distribution and drift in the vicinity of the Gulf of Maine offshore banks and their probable origins

    FISHERIES OCEANOGRAPHY, Issue 2 2005
    G. C. HARDING
    Abstract Surveys for lobster larvae in offshore waters of the north-eastern Gulf of Maine in 1983, 1987 and 1989 confirm that local hatching occurs mainly at depths <100 m over the banks, including Georges and Browns Banks. Detailed studies in the vicinity of Georges Bank in late July of both 1987 and 1989 indicate that the first and second moult stages were located primarily over the bank whereas stages III and IV lobster were collected both over and off the bank. At times stage IV lobster were more abundant off the bank than over it. The condition of stage III and IV lobster, as measured by a lipid index, was better off than over Georges Bank in 1988 and 1989 indicating a possible physiological advantage to being off the bank. In addition, the higher surface temperatures off Georges Bank would shorten larval development time to settlement. To determine the probable hatch sites of stage IV lobster collected off of Browns Bank in 1983 and off of Georges in 1987 and 1989, a 3-D circulation model of the Gulf of Maine was used to simulate larval lobster drift backwards in time. In all cases, areas off Cape Cod, MA, and off Penobscot Bay, ME were suggested as the source of the larvae, although most of the larval trajectories never reached these near-shore waters that are well-known, larval hatching areas. The model-projected larval release times match most closely the observed inshore hatch off Massachusetts but model uncertainties mean that coastal Maine cannot be ruled out as a source. Georges Bank is also a potential source because the present model does not take into account short-term wind events, off-bank eddy transport or the possibility of directed off-bank larval swimming. Examination of weather records prior to and during our 1988 and 1989 sampling periods indicates that winds were not of sufficient intensity and duration to induce larval transport off Georges Bank. The shedding of eddies from the northern flank of Georges Bank into the Gulf of Maine are a relatively common phenomenon during summer but not enough is known about them to evaluate their contribution to possible cross-bank transport of lobster larvae. Directed larval swimming is another possible source for the stage IV lobster found near Georges Bank. Plankton distributions across the northern frontal zone of Georges Bank in 1988 were used as proxies for the scarce larval lobsters. The more surface distribution of the microplankton, in particular, supports the possibility that wind and eddy events may be important in the transport of stage III and IV lobsters off of Georges Bank. Further studies are needed to evaluate these possible additional sources of advanced stage lobster larvae found off of the offshore banks. [source]


    Palaeomagnetism, rock magnetism and geochemistry of Jurassic dykes and correlative redbeds, Massachusetts, USA

    GEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2000
    Suzanne A. McEnroe
    Jurassic diabase dykes, sills and sedimentary rocks in central Massachusetts were sampled for palaeomagnetic analysis. The intrusions fall into three of the chemical types for eastern North American diabases: high TiO2 quartz-normative (Holden); low TiO2 quartz-normative (Ware); and high Fe2O3 quartz-normative (Pelham,Loudville). The characteristic magnetizations in the majority of intrusive samples unblock between 550 °C and 580 °C, with Curie temperatures in a discrete interval between 556 °C and 580 °C. The dominant remanence in the diabases is carried by C1 to C3 oxidation-exsolved titanomagnetite occurring as euhedral grains, as fine needles or dust in the matrix, as devitrifed glass, and as fine magnetite-ilmenite-silicate symplectite. In some dykes, titanomagnetite was further modified by deuteric oxidation during post-magmatic cooling, creating titanomaghematite and/or a granulation of the magnetite. Palaeopoles for the three diabase groups are: Holden, 60.1°N, 80.5°E, A95 = 4.1°; Ware, 73.5°N, 85.8°E, A95 = 3.9°; and Pelham,Loudville, 65.3°N, 95.6°E, A95 = 4.1°. These data are combined with samples from two stratigraphic sections through the Early Jurassic part of the Sugarloaf Formation in the Deerfield Basin representing both fine-grained mudstones and coarser arkoses. These haematite-dominated rocks reveal several components of magnetization, a steep recent field direction, an intermediate secondary diagenetic overprint direction in both mudstones and arkoses, and a high-temperature shallow primary direction found only in the mudstones. Palaeopoles for the Sugarloaf Formation are: mudstones, 57.7°N, 81.3°E, A95 = 9.1°; and arkoses, 75.1°N, 131.6°E, A95 = 5.9°. Based on the new palaeomagnetic data reported here, the North American plate in the Middle Jurassic was at higher palaeolatitudes than indicated by the present North American apparent polar wander path. [source]


    Vertical partitioning of CO2 production within a temperate forest soil

    GLOBAL CHANGE BIOLOGY, Issue 6 2006
    ERIC A. DAVIDSON
    Abstract The major driving factors of soil CO2 production , substrate supply, temperature, and water content , vary vertically within the soil profile, with the greatest temporal variations of these factors usually near the soil surface. Several studies have demonstrated that wetting and drying of the organic horizon contributes to temporal variation in summertime soil CO2 efflux in forests, but this contribution is difficult to quantify. The objectives of this study were to partition CO2 production vertically in a mixed hardwood stand of the Harvard Forest, Massachusetts, USA, and then to use that partitioning to evaluate how the relative contributions of CO2 production by genetic soil horizon vary seasonally and interannually. We measured surface CO2 efflux and vertical soil profiles of CO2 concentration, temperature, water content, and soil physical characteristics. These data were applied to a model of effective diffusivity to estimate CO2 flux at the top of each genetic soil horizon and the production within each horizon. A sensitivity analysis revealed sources of uncertainty when applying a diffusivity model to a rocky soil with large spatial heterogeneity, especially estimates of bulk density and volumetric water content and matching measurements of profiles and surface fluxes. We conservatively estimate that the O horizon contributed 40,48% of the total annual soil CO2 efflux. Although the temperature sensitivity of CO2 production varied across soil horizons, the partitioning of CO2 production by horizon did not improve the overall prediction of surface CO2 effluxes based on temperature functions. However, vertical partitioning revealed that water content covaried with CO2 production only in the O horizon. Large interannual variations in estimates of O horizon CO2 production indicate that this layer could be an important transient interannual source or sink of ecosystem C. [source]


    Tidal Effects on Ground Water Discharge Through a Sandy Marine Beach

    GROUND WATER, Issue 7 2004
    Daniel W. Urish
    Tidal fluctuations along the salt water boundary of a sandy beach affect the magnitude, location, timing, and salinity of both subaerial and submarine ground water discharge. Detailed studies of shoreline discharge from an unconfined aquifer at two sites in an embayment on the Cape Cod, Massachusetts, coastline provide insight into the highly dynamic spatial and temporal nature of discharge along sandy beaches affected by the tide. The constantly moving tidal boundary over a sloping beach results in a shoreline-perpendicular discharge zone of 10 to 20 m, with ,35% to 55% of the discharge being submarine discharge. The distribution of fresh ground water through a beach face varies greatly, depending primarily on the tidal cycle and range, the heterogeneous characteristics of the beach sediments, and the beach geometry. The estimated relative volume of discharge varies temporally with tidal fluctuations, with the greatest discharge occurring during early to mid ebbing tide and location of greatest estimated discharge moving seaward during ebbing tide. This is determined using net hydraulic head calculations in monitoring wells set in a shoreline-perpendicular transect in the beach. The salinity of discharge varies temporally from near fresh water values of 1 part per thousand (ppt) to near coastal salt water values of 30 ppt, being saltiest at the start of discharge as the tide ebbs and freshest during a low tide period of ,2 h. Of the discharge volume, ,65% to 85% is estimated to be from salt water that infiltrates during high tide episodes. This study highlights the complexity of the dynamic coastal ground water discharge phenomenon and provides insight into the hydraulic mechanisms involved. While there is a general pattern to sandy beach discharge, comparison of results from beaches studied at Cape Cod indicates that the temporal and spatial details of the discharge is very site-specific. [source]


    Show Us the Money: Lessons in Transparency from State Pharmaceutical Marketing Disclosure Laws

    HEALTH SERVICES RESEARCH, Issue 1 2010
    Susan Chimonas
    Objective. To assess legislation requiring drug companies to report gifts to providers, and to evaluate the information obtained. Data Sources. Data included legislation in Vermont, Minnesota, Maine, Massachusetts, West Virginia, and the District of Columbia, and company disclosure data from Vermont. Study Design. We evaluated the strengths and weaknesses of state legislation. We also analyzed 4 years of company disclosures from Vermont, assessing the value and distribution of industry,provider exchanges and identifying emerging trends in companies' practices. Data Collection Methods. State legislation is publically available. We obtained Vermont's data through requests to the state's Attorney General's office. Principal Findings. Of the state laws, only Vermont's yielded robust, publically available data. These data show gifting was dominated by a few major corporations, and <2 percent of Vermont's prescribers received 69 percent of gifts and payments. Companies were especially generous to specialists in psychiatry, endocrinology/diabetes/metabolism, internal medicine, and neurology. Companies increasingly used loopholes in the law to avoid public scrutiny. Conclusions. Disclosure laws are an important first step in bringing greater transparency to physician,industry relationships. But flaws and weaknesses limit the states' ability to render physician,industry exchanges fully transparent. Future efforts should build on these lessons to render physician,industry relationships fully transparent. [source]


    Revealing and Resolving Patient Safety Defects: The Impact of Leadership WalkRounds on Frontline Caregiver Assessments of Patient Safety

    HEALTH SERVICES RESEARCH, Issue 6 2008
    Allan Frankel
    Objective. To evaluate the impact of rigorous WalkRounds on frontline caregiver assessments of safety climate, and to clarify the steps and implementation of rigorous WalkRounds. Data Sources/Study Setting. Primary outcome variables were baseline and post WalkRounds safety climate scores from the Safety Attitudes Questionnaire (SAQ). Secondary outcomes were safety issues elicited through WalkRounds. Study period was August 2002 to April 2005; seven hospitals in Massachusetts agreed to participate; and the project was implemented in all patient care areas. Study Design. Prospective study of the impact of rigorously applied WalkRounds on frontline caregivers assessments of safety climate in their patient care area. WalkRounds were conducted weekly and according to the seven-step WalkRounds Guide. The SAQ was administered at baseline and approximately 18 months post-WalkRounds implementation to all caregivers in patient care areas. Results. Two of seven hospitals complied with the rigorous WalkRounds approach; hospital A was an academic teaching center and hospital B a community teaching hospital. Of 21 patient care areas, SAQ surveys were received from 62 percent of respondents at baseline and 60 percent post WalkRounds. At baseline, 10 of 21 care areas (48 percent) had safety climate scores below 60 percent, whereas post-WalkRounds three care areas (14 percent) had safety climate scores below 60 percent without improving by 10 points or more. Safety climate scale scores in hospital A were 62 percent at baseline and 77 percent post-WalkRounds (t=2.67, p=.03), and in hospital B were 46 percent at baseline and 56 percent post WalkRounds (t=2.06, p=.06). Main safety issues by category were equipment/facility (A [26 percent] and B [33 percent]) and communication (A [24 percent] and B [18 percent]). Conclusions. WalkRounds implementation requires significant organizational will; sustainability requires outstanding project management and leadership engagement. In the patient care areas that rigorously implemented WalkRounds, frontline caregiver assessments of patient safety increased. SAQ results such as safety climate scores facilitate the triage of quality improvement efforts, and provide consensus assessments of frontline caregivers that identify themes for improvement. [source]


    Project Labor Agreements' Effect on School Construction Costs in Massachusetts

    INDUSTRIAL RELATIONS, Issue 1 2010
    DALE BELMAN
    This paper investigates the impact of Project Labor Agreements (PLAs) on school construction cost in Massachusetts. Although simple models exhibit a large positive effect of PLAs on construction costs, such effects are absent from more completely specified models. Further investigation finds sufficient dissimilarity in schools built with and without PLAs that it is difficult to distinguish the cost effects of PLAs from the cost effects of factors that underlie the use of PLAs. [source]


    Early life risk factors in cancer: The relation of birth weight to adult obesity

    INTERNATIONAL JOURNAL OF CANCER, Issue 6 2003
    Nicole M. Leong
    Abstract The intrauterine environment appears to play a role in the development of adult diseases, including several prominent cancers. Our study aims to characterize the relationship between birth weight, a measure of the intrauterine environment, and adult obesity. A population-based sample of women aged 50,79, living in the states of Massachusetts, New Hampshire or Wisconsin, were randomly selected from lists of licensed drivers and Medicare beneficiaries to participate as controls in a case-control study of breast cancer. Information on birth weight, adult height and adult weight were collected through structured telephone interviews from 1992,1995. Our analysis was based on 1,850 interviews. A U-shaped relationship between birth weight and adult BMI was observed. Median adult BMI for the birth weight categories (in kilograms) <2.3, 2.3<2.5, 2.5<3.2, 3.2<3.9, 3.9<4.5 and ,4.5 were 26.6, 24.4, 25.1, 25.5, 25.4 and 26.6 kg/m respectively. Compared to women 2.5<3.2 kg at birth, women in highest birth weight category (,4.5 kg) had an odds ratio of 1.99 (95% CI 1.13,3.48) of being obese (,30 kg/m2) as adults. The odds ratio for women in the <2.3 kg birth weight category was 1.67 (95% CI 1.01,2.76). These data suggest that both low and high birth weights are associated with higher adult BMI and support the hypothesis that fetal experience may influence adult obesity with potential consequences for risk of several major cancers. © 2002 Wiley-Liss, Inc. [source]


    Cost-sensitive learning and decision making for massachusetts pip claim fraud data

    INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 12 2004
    Stijn Viaene
    In this article, we investigate the issue of cost-sensitive classification for a data set of Massachusetts closed personal injury protection (PIP) automobile insurance claims that were previously investigated for suspicion of fraud by domain experts and for which we obtained cost information. After a theoretical exposition on cost-sensitive learning and decision-making methods, we then apply these methods to the claims data at hand to contrast the predictive performance of the documented methods for a selection of decision tree and rule learners. We use standard logistic regression and (smoothed) naive Bayes as benchmarks. © 2004 Wiley Periodicals, Inc. Int J Int Syst 19: 1197,1215, 2004. [source]


    The North American Naturalization Gap: An Institutional Approach to Citizenship Acquisition in the United States and Canada,

    INTERNATIONAL MIGRATION REVIEW, Issue 1 2002
    Irene Bloemraad
    Using 1990 U.S. Census 5% PUMS and 1991 Canadian Census 3% public and 20% restricted microfiles, this article demonstrates the existence of a North American naturalization gap: immigrants living in Canada are on average much more likely to be citizens than their counterparts in the United States, and they acquire citizenship much faster than those living south of the border. Current theories explaining naturalization differences , focusing on citizenship laws, group traits or the characteristics of individual migrants , fail to explain the naturalization gap. Instead, I propose an institutional approach to citizenship acquisition. States' normative stances regarding immigrant integration (interventionist or autonomous) generate integrated or disconnected institutional configurations between government, ethnic organizations and individuals. Evidence from a case study of Portuguese immigrants living in Massachusetts and Ontario suggests that in Toronto government bureaucrats and federal policy encourage citizenship through symbolic support and instrumental aid to ethnic organizations and community leaders. In contrast, Boston area grassroots groups are expected to mobilize and aid their constituents without direct state support, resulting in lower citizenship levels. [source]


    Risk of Hip Fracture in Disabled Community-Living Older Adults

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 1 2003
    Louise C. Walter MD
    OBJECTIVES: To determine the rate of hip fracture and risk factors associated with hip fractures in disabled older persons who enroll in the Program of All-Inclusive Care for the Elderly (PACE), a program providing comprehensive care to community-living nursing-home-eligible persons. DESIGN: Prospective cohort study between January 1990 and December 1997. SETTING: The twelve PACE demonstration sites: San Francisco, California; Columbia, South Carolina; Detroit, Michigan; Denver, Colorado; East Boston, Massachusetts; El Paso, Texas; Milwaukee, Wisconsin; Oakland, California; Portland, Oregon; Rochester, New York; Sacramento, California; and the Bronx, New York. PARTICIPANTS: Five thousand one hundred eighty-seven individuals in PACE; mean age 79, 71% female, 49% white, 47% with dementia. MEASUREMENTS: Functional status, cognitive status, demographics, and comorbid conditions were recorded on all the participants, who were tracked for occurrence of a hip fracture. The goals were to determine the rate of hip fracture and identify risk factors. RESULTS: Two hundred thirty-eight hip fractures (4.6%) occurred during follow-up. The rate of hip fracture was 2.2% per person-year. Four independent predictors of hip fracture were identified using Cox proportional hazard analysis: age of 75 and older (adjusted hazard ratio (HR) = 2.0, 95% confidence interval (CI) = 1.4,2.8); white ethnicity (HR = 2.1, 95% CI = 1.6,2.8); ability to transfer independently to and from bed, chair, and toilet (HR = 3.0, 95% CI = 1.2,7.2); and five or more Short Portable Mental Status Questionnaire errors (HR = 1.6, 95% CI = 1.3,2.1). The incidence of hip fracture ranged from 0.5% per person-year in persons with zero to one independent risk factors to 4.7% per person-year in those with all four independent risk factors. CONCLUSIONS: The rate of hip fracture in this cohort of disabled community-living older adults was similar to that reported in nursing home cohorts. Older age, white race, ability to transfer independently, and cognitive impairment were independent predictors of hip fracture. Persons with these risk factors should be targeted for preventive interventions, which should include strategies for making transferring safer. [source]


    Predicting Cognitive Impairment in High-Functioning Community-Dwelling Older Persons: MacArthur Studies of Successful Aging

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 6 2002
    Joshua Chodosh MD, MSHS
    OBJECTIVES: To examine whether simple cognitive tests, when applied to cognitively intact older persons, are useful predictors of cognitive impairment 7 years later. DESIGN: Cohort study. SETTING: Durham, North Carolina; East Boston, Massachusetts; and New Haven, Connecticut, areas that are part of the National Institute on Aging Established Populations for Epidemiological Studies of the Elderly. PARTICIPANTS: Participants, aged 70 to 79, from three community-based studies, who were in the top third of this age group, based on physical and cognitive functional status. MEASUREMENTS: New onset of cognitive impairment as defined by a score of less than 7 on the Short Portable Mental Status Questionnaire (SPMSQ) in 1995. RESULTS: At 7 years, 21.8% (149 of 684 subjects) scored lower than 7 on the SPMSQ. Using multivariate logistic regression, three baseline (1988) cognitive tests predicted impairment in 1995. These included two simple tests of delayed recall,the ability to remember up to six items from a short story and up to 18 words from recall of Boston Naming Test items. For each story item missed, the adjusted odds ratio (AOR) for cognitive impairment was 1.44 (95% confidence interval (CI) = 1.16,1.78, P < .001). For each missed item from the word list, the AOR was 1.20 (95% CI = 1.09,1.31, P < .001). The Delayed Recognition Span, which assesses nonverbal memory, also predicted cognitive impairment, albeit less strongly (odds ratio = 1.06 per each missed answer, 95% CI = 1.003,1.13, P = .04). CONCLUSIONS: This study identifies measures of delayed recall and recognition as significant early predictors of subsequent cognitive decline in high-functioning older persons. Future efforts to identify those at greatest risk of cognitive impairment may benefit by including these measures. [source]


    The Value of Serum Albumin and High-Density Lipoprotein Cholesterol in Defining Mortality Risk in Older Persons with Low Serum Cholesterol

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 9 2001
    Stefano Volpato MD
    OBJECTIVES: To investigate the relationship between low cholesterol and mortality in older persons to identify, using information collected at a single point in time, subgroups of persons with low and high mortality risk. DESIGN: Prospective cohort study with a median follow-up period of 4.9 years. SETTINGS: East Boston, Massachusetts; New Haven, Connecticut; and Iowa and Washington counties, Iowa. PARTICIPANTS: Four thousand one hundred twenty-eight participants (64% women) age 70 and older at baseline (mean 78.7 years, range 70,103); 393 (9.5%) had low cholesterol, defined as ,160 mg/dl. MEASUREMENTS: All-cause mortality and mortality not related to coronary heart disease and ischemic stroke. RESULTS: During the follow-up period there were 1,117 deaths. After adjustment for age and gender, persons with low cholesterol had significantly higher mortality than those with normal and high cholesterol. Among subjects with low cholesterol, those with albumin> 38 g/L had a significant risk reduction compared with those with albumin ,38 g/L (relative risk (RR) = 0.57; 95% confidence interval (CI) = 0.41,0.79). Within the higher albumin group, high-density lipoprotein cholesterol (HDL-C) level further identified two subgroups of subjects with different risks; participants with HDL-C <47 mg/dl had a 32% risk reduction (RR = 0.68; 95% CI = 0.47,0.99) and those with HDL-C ,47 mg/dl had a 62% risk reduction (RR = 0.38; 95% CI = 0.20,0.68), compared with the reference category; those with albumin ,38 g/L and HDL-C <47 mg/dl. CONCLUSIONS: Older persons with low cholesterol constitute a heterogeneous group with regard to health characteristics and mortality risk. Serum albumin and HDL-C can be routinely used in older patients with low cholesterol to distinguish three subgroups with different prognoses: (1) high risk (low albumin), (2) intermediate risk (high albumin and low HDL-C), and (3) low risk (high albumin and high HDL-C). [source]


    X-ray diffraction analysis of stacking and twin faults in f.c.c. metals: a revision and allowance for texture and non-uniform fault probabilities

    JOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 2 2000
    L. Velterop
    A revision is presented of the original description by Warren [X-ray Diffraction, (1969), pp. 275,298. Massachusetts: Addison-Wesley] of the intensity distribution of powder-pattern reflections from f.c.c. metal samples containing stacking and twin faults. The assumptions (in many cases unrealistic) that fault probabilities need to be very small and equal for all fault planes and that the crystallites in the sample have to be randomly oriented have been removed. To elucidate the theory, a number of examples are given, showing how stacking and twin faults change the shape and position of diffraction peaks. It is seen that significant errors may arise from Warren's assumptions, especially in the peak maximum shift. Furthermore, it is explained how to describe powder-pattern reflections from textured specimens and specimens with non-uniform fault probabilities. Finally, it is discussed how stacking- and twin-fault probabilities (and crystallite sizes) can be determined from diffraction line-profile measurements. [source]