300 research outputs found
Cultural Value Orientations, Attributions, and Breast Cancer Screening Behaviors
Discrepancies in breast cancer screening behavior exist among various ethnic groups in the United States (Jacobs & Lauderdale, 2001), with Latino American women reporting particularly low screening rates in comparison to Anglo American women (ACS, 2002). Research indicates that behavior is in part influenced by aspects of culture and relevant psychological processes (Betancourt & Lopez, 1993; Betancourt & Fuentes, 2001). This study was designed to investigate the relations among cultural values, attributional processes, and breast cancer screening behavior among Anglo and Latino women. This study also investigated the influence of acculturation among Latino women in relation to the other study variables. The Value Orientation Scale (Betancourt & McMillin- Williams, 2003), the Revised Causal Dimension Scale (McAuley, Duncan, & Russel, 1992), the Behavior Risk Factor Surveillance System Questionnaire (CDC, 1997), and Stephenson\u27s Multigroup Acculturation Scale (Stephenson, 2001) were used for the study. Bentler\u27s (1995) analysis of structural equations (EQS) program was used to test a model of the relations among culture, attributions, and breast cancer screening behaviors resulting in a good fit of the data. Level of acculturation had little effect on the study variables
Workplace Turbulence and Workforce Preparedness
The year 1973 marked a divide in the postwar economy.1 During the 25 years between 1948 and 1973, private sector productivity increased at an annual rate of 2.9%. Productivity improvement after 1973 fell way below this long-term trend, leveling off at about 0.6% a year until 1981 and rising to only 1.6% a year between 1981 and 1987. A similar pattern is reflected in the real wages of the workforce.2The conventional interpretation of this difference in the U.S. economy before and after 1973 is that it reflects the combined influence of the OPEC oil shock and the influx into the labor market of inexperienced workers born in the postwar baby boom, possibly reinforced by growth in regulatory costs.3 However, when the productivity data are analyzed in a growth accounting framework, these economic factors can only account for about two thirds of the productivity decline.4 What then explains the balance of the shortfall in productivity? Many analysts have pointed to the intangible effects on managers of increased economic uncertainty since 1973âgrowing business cautiousness, increased emphasis on short-term financial objectives, and inadequate entrepreneurial incentives.5 But economic change and uncertainty can also affect productivity through their impact on jobs and workers
Simulating Effects of Variable Stoichiometry and Temperature on Mixotrophy in the Harmful Dinoflagellate Karlodinium veneficum
Results from a dynamic mathematical model are presented simulating the growth of the harmful algal bloom (HAB) mixotrophic dinoflagellate Karlodinium veneficum and its algal prey, Rhodomonas salina. The model describes carbon-nitrogen-phosphorus-based interactions within the mixotroph, interlinking autotrophic and phagotrophic nutrition. The model was tuned to experimental data from these species grown under autotrophic conditions and in mixed batch cultures in which nitrogen:phosphorus stoichiometry (input molar N:P of 4, 16, and 32) of both predator and prey varied. A good fit was attained to all experimentally derived carbon biomass data. The potential effects of temperature and nutrient changes on promoting growth of prey and thus K. veneficum bloom formation were explored using this simulation platform. The simulated biomass of K. veneficum was highest when they were functioning as mixotrophs and when they consumed prey under elevated N:P conditions. The scenarios under low N:P responded differently, with simulations showing larger deviation between mixotrophic and autotrophic growth, depending on temperature. When inorganic nutrients were in balanced proportions, lower biomass of the mixotroph was attained at all temperatures in the simulations, suggesting that natural systems might be more resilient against Karlodinium HAB development in warming conditions if nutrients were available in balanced proportions. These simulations underscore the need for models of HAB dynamics to include consideration of prey; modeling HAB as autotrophs is insufficient. The simulations also imply that warmer, wetter springs that may bring more N with lower N:P, such as predicted under climate change scenarios for Chesapeake Bay, may be more conducive to development of these HABs. Prey availability may also increase with temperature due to differential growth temperature responses of K. veneficum and its prey
Ocean acidification with (de)eutrophication will alter future phytoplankton growth and succession
Human activity causes ocean acidification (OA) though the dissolution of anthropogenically generated CO2 into seawater, and eutrophication through the addition of inorganic nutrients. Eutrophication increases the phytoplankton biomass that can be supported during a bloom, and the resultant uptake of dissolved inorganic carbon during photosynthesis increases water-column pH (bloom-induced basification). This increased pH can adversely affect plankton growth. With OA, basification commences at a lower pH. Using experimental analyses of the growth of three contrasting phytoplankton under different pH scenarios, coupled with mathematical models describing growth and death as functions of pH and nutrient status, we show how different conditions of pH modify the scope for competitive interactions between phytoplankton species. We then use the models previously configured against experimental data to explore how the commencement of bloom-induced basification at lower pH with OA, and operating against a background of changing patterns in nutrient loads, may modify phytoplankton growth and competition. We conclude that OA and changed nutrient supply into shelf seas with eutrophication or de-eutrophication (the latter owing to pollution control) has clear scope to alter phytoplankton succession, thus affecting future trophic dynamics and impacting both biogeochemical cycling and fisheries
Creating an enabling environment for research impact (REACH Discussion document)
Research should benefit society: that is widely accepted. There has been much written on how to design research to deliver impact through equitable partnerships, co-production, and more. However, there has been less reflection on the enabling environment that funders and universities create to support research to have impact. In this brief we explore the experiences of creating impact through research in international development, and the ways in which the enabling environment facilitated impact drawing on perspectives of researchers, research users from government and UN agencies, and funders. We highlight three areas for funders to focus on strengthening enabling environments: (1) foster science-practitioner networks, (2) enhance collaborative research environments based on equitable partnerships, and (3) shift financing and incentives to sustain partnerships for impact at scale
B->eta(') Form Factors in QCD
We calculate the semileptonic form factors and
from QCD sum rules on the light-cone (LCSRs), to NLO in
QCD, and for small to moderate q^2, . We include in particular the so-called singlet contribution, i.e.\
weak annihilation of the B meson with the emission of two gluons which, thanks
to the U(1) anomaly, couple directly to \etap. This effect is
included to leading-twist accuracy. This contribution has been neglected in
previous calculations of the form factors from LCSRs. We find that the singlet
contribution to can be up to 20%, while that to is, as expected, much smaller and below 3%. We also suggest to measure
the ratio to better constrain the size of the singlet
contribution.Comment: 21 pages; version to appear in JHE
Long-Term Follow-Up of Cardiac Function and Quality of Life for Patients in NSABP Protocol B-31/NRG Oncology: A Randomized Trial Comparing the Safety and Efficacy of Doxorubicin and Cyclophosphamide (AC) Followed by Paclitaxel With AC Followed by Paclitaxel and Trastuzumab in Patients With Node-Positive Breast Cancer With Tumors Overexpressing Human Epidermal Growth Factor Receptor 2
Purpose
Early cardiac toxicity is a risk associated with adjuvant chemotherapy plus trastuzumab. However, objective measures of cardiac function and health-related quality of life are lacking in long-term follow-up of patients who remain cancer free after completion of adjuvant treatment.
Patients and Methods
Patients in NSABP Protocol B-31 received anthracycline and taxane chemotherapy with or without trastuzumab for adjuvant treatment of node-positive, human epidermal growth factor receptor 2âpositive early-stage breast cancer. A long-term follow-up assessment was undertaken for patients who were alive and disease free, which included measurement of left ventricular ejection fraction by multigated acquisition scan along with patient-reported outcomes using the Duke Activity Status Index (DASI), the Medical Outcomes Study questionnaire, and a review of current medications and comorbid conditions.
Results
At a median follow-up of 8.8 years among eligible participants, five (4.5%) of 110 in the control group and 10 (3.4%) of 297 in the trastuzumab group had a \u3e 10% decline in left ventricular ejection fraction from baseline to a value \u3c 50%. Lower DASI scores correlated with age and use of medications for hypertension, cardiac conditions, diabetes, and hyperlipidemia, but not with whether patients had received trastuzumab.
Conclusion
In patients without underlying cardiac disease at baseline, the addition of trastuzumab to adjuvant anthracycline and taxane-based chemotherapy does not result in long-term worsening of cardiac function, cardiac symptoms, or health-related quality of life. The DASI questionnaire may provide a simple and useful tool for monitoring patient-reported changes that reflect cardiac function
Defining Planktonic Protist Functional Groups on Mechanisms for Energy and Nutrient Acquisition: Incorporation of Diverse Mixotrophic Strategies
Arranging organisms into functional groups aids ecological research by grouping organisms (irrespective of phylogenetic origin) that interact with environmental factors in similar ways. Planktonic protists traditionally have been split between photoautotrophic âphytoplanktonâ and phagotrophic âmicrozoo-planktonâ.
However, there is a growing recognition of the importance of mixotrophy in euphotic aquatic systems, where
many protists often combine photoautotrophic and phagotrophic modes of nutrition. Such organisms do not align with the traditional dichotomy of phytoplankton and microzooplankton. To reflect this understanding,we
propose a new functional grouping of planktonic protists in an eco- physiological context: (i) phagoheterotrophs lacking phototrophic capacity, (ii) photoautotrophs lacking phagotrophic capacity,(iii)
constitutive mixotrophs (CMs) as phagotrophs with an inherent capacity for phototrophy, and (iv) non-constitutive mixotrophs (NCMs) that acquire their phototrophic capacity by ingesting specific (SNCM) or
general non-specific (GNCM) prey. For the first time, we incorporate these functional groups within
a foodweb structure and show, using model outputs, that there is scope for significant changes in trophic dynamics depending on the protist functional type description. Accord- ingly, to better reflect the role
of mixotrophy, we recommend that as important tools for explanatory and predictive research, aquatic food-web
and biogeochemical models need to redefine the protist groups within their frameworks
A Practical, One-Pot Synthesis of Highly Substituted Thiophenes and Benzo[b]thiophenes from Bromoenynes and o-Alkynylbromobenzenes
An efficient synthesis of thiophenes and benzo[b]thiophenes has been developed from easily available bromoenynes and o-alkynylbromobenzene derivatives. This novel one-pot procedure involves a Pd-catalyzed CâS bond formation using a hydrogen sulfide surrogate followed by a heterocyclization reaction. Moreover, in situ functionalization with selected electrophiles further expands the potential of this methodology to the preparation of the corresponding highly substituted sulfur heterocycles.Junta de Castilla y Leon (BU021A09 and GR-172) and Ministerio de Ciencia e Innovacion (MICINN) and FEDER (CTQ2010-15358 and CTQ2009-09949/BQU) for financial support. P.G.-G. and M.A.F.-R. thank MICINN for "Juan de la Cierva" and "Ramon y Cajal" contractsJunta de Castilla y Leon (BU021A09 and GR-172) and Ministerio de Ciencia e Innovacion (MICINN) and FEDER (CTQ2010-15358 and CTQ2009-09949/BQU) for financial support. P.G.-G. and M.A.F.-R. thank MICINN for "Juan de la Cierva" and "Ramon y Cajal" contractsThis document is the Accepted Manuscript version of a Published Work that appeared in final form in
Organic Letters, copyright © American Chemical Society after peer review and technical editing by the publisher
Use and Misuse of QCD Sum Rules in Heavy-to-light Transitions: the Decay Reexamined
The existing calculations of the form factors describing the decay from QCD sum rules have yielded conflicting results at small values of
the invariant mass squared of the lepton pair. We demonstrate that the
disagreement originates from the failure of the short-distance expansion to
describe the meson distribution amplitude in the region where almost the
whole momentum is carried by one of the constituents. This limits the
applicability of QCD sum rules based on the short-distance expansion of a
three-point correlation function to heavy-to-light transitions and calls for an
expansion around the light-cone, as realized in the light-cone sum rule
approach. We derive and update light-cone sum rules for all the semileptonic
form factors, using recent results on the meson distribution amplitudes.
The results are presented in detail together with a careful analysis of the
uncertainties, including estimates of higher-twist effects, and compared to
lattice calculations and recent CLEO measurements. We also derive a set of
``improved'' three-point sum rules, in which some of the problems of the
short-distance expansion are avoided and whose results agree to good accuracy
with those from light-cone sum rules.Comment: 34 pages Latex; two references added; one typo in one table
corrected; accepted for publication in Phys. Rev.
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