33 research outputs found
Electrical lithosphere beneath the Kaapvaal craton, southern Africa
Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 116 (2011): B04105, doi:10.1029/2010JB007883.A regional-scale magnetotelluric (MT) experiment across the southern African Kaapvaal craton and surrounding terranes, called the Southern African Magnetotelluric Experiment (SAMTEX), has revealed complex structure in the lithospheric mantle. Large variations in maximum resistivity at depths to 200â250 km relate directly to age and tectonic provenance of surface structures. Within the central portions of the Kaapvaal craton are regions of resistive lithosphere about 230 km thick, in agreement with estimates from xenolith thermobarometry and seismic surface wave tomography, but thinner than inferred from seismic body wave tomography. The MT data are unable to discriminate between a completely dry or slightly âdampâ (a few hundred parts per million of water) structure within the transitional region at the base of the lithosphere. However, the structure of the uppermost âŒ150 km of lithosphere is consistent with enhanced, but still low, conductivities reported for hydrous olivine and orthopyroxene at levels of water reported for Kaapvaal xenoliths. The electrical lithosphere around the Kimberley and Premier diamond mines is thinner than the maximum craton thickness found between Kimberley and Johannesburg/Pretoria. The mantle beneath the Bushveld Complex is highly conducting at depths around 60 km. Possible explanations for these high conductivities include graphite or sulphide and/or iron metals associated with the Bushveld magmatic event. We suggest that one of these conductive phases (most likely melt-related sulphides) could electrically connect iron-rich garnets in a garnet-rich eclogitic composition associated with a relict subduction slab.In addition
to the funding and logistical support provided by SAMTEX consortium
members, this work is also supported by research grants from the National
Science Foundation (EARâ0309584 and EARâ0455242 through the Continental
Dynamics Program), the Department of Science and Technology,
South Africa, and Science Foundation of Ireland (grant 05/RFP/
GEO001)
Gynecologic oncology patients' satisfaction and symptom severity during palliative chemotherapy
BACKGROUND: Research on quality and satisfaction with care during palliative chemotherapy in oncology patients has been limited. The objective was to assess the association between patient's satisfaction with care and symptom severity and to evaluate test-retest of a satisfaction survey in this study population. METHODS: A prospective cohort of patients with recurrent gynecologic malignancies receiving chemotherapy were enrolled after a diagnosis of recurrent cancer. Patients completed the Quality of End-of-Life care and satisfaction with treatment scale (QUEST) once upon enrollment in an outpatient setting and again a week later. Patients also completed the Mini-Mental Status Exam, the Hospital Anxiety/Depression Scale, a symptom severity scale and a demographic survey. Student's t-test, correlation statistics and percent agreement were used for analysis. RESULTS: Data from 39 patients were analyzed. Mean (SD) quality of care summary score was 41.95 (2.75) for physicians and 42.23 (5.42) for nurses (maximum score was 45; p = 0.76 for difference in score between providers). Mean (SD) satisfaction of care summary score was 29.03 (1.92) for physicians and 29.28 (1.70) for nurses (maximum score was 30; p = 0.49 for difference between providers). Test-retest for 33 patients who completed both QUEST surveys had high percent agreement (74â100%), with the exception of the question regarding the provider arriving late (45 and 53%). There was no correlation between quality and satisfaction of care and symptom severity. Weakness was the most common symptom reported. Symptom severity correlated with depression (r = 0.577 p < 0.01). There was a trend towards a larger proportion of patients reporting pain who had three or more prior chemotherapy regimens (p = 0.075). Prior number of chemotherapy regimens or time since diagnosis was not correlated with symptom severity score. Anxiety and depression were correlated with each other (r = 0.711, p < 0.01). There was no difference in symptom severity score at enrollment between those patients who have since died (n = 19) versus those who are still alive. CONCLUSION: The QUEST Survey has test-retest reliability when used as a written instrument in an outpatient setting. However, there was no correlation between this measure and symptom severity. Patient evaluation of care may be more closely related to the interpersonal aspects of the health care provider relationship than it is to physical symptoms
Models of marine fish biodiversity : assessing predictors from three habitat classification schemes
Prioritising biodiversity conservation requires knowledge of where biodiversity occurs. Such knowledge, however, is often lacking. New technologies for collecting biological and physical data coupled with advances in modelling techniques could help address these gaps and facilitate improved management outcomes. Here we examined the utility of environmental data, obtained using different methods, for developing models of both uni- and multivariate biodiversity metrics. We tested which biodiversity metrics could be predicted best and evaluated the performance of predictor variables generated from three types of habitat data: acoustic multibeam sonar imagery, predicted habitat classification, and direct observer habitat classification. We used boosted regression trees (BRT) to model metrics of fish species richness, abundance and biomass, and multivariate regression trees (MRT) to model biomass and abundance of fish functional groups. We compared model performance using different sets of predictors and estimated the relative influence of individual predictors. Models of total species richness and total abundance performed best; those developed for endemic species performed worst. Abundance models performed substantially better than corresponding biomass models. In general, BRT and MRTs developed using predicted habitat classifications performed less well than those using multibeam data. The most influential individual predictor was the abiotic categorical variable from direct observer habitat classification and models that incorporated predictors from direct observer habitat classification consistently outperformed those that did not. Our results show that while remotely sensed data can offer considerable utility for predictive modeling, the addition of direct observer habitat classification data can substantially improve model performance. Thus it appears that there are aspects of marine habitats that are important for modeling metrics of fish biodiversity that are not fully captured by remotely sensed data. As such, the use of remotely sensed data to model biodiversity represents a compromise between model performance and data availability
31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two
Background
The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd.
Methods
We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background.
Results
First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001).
Conclusions
In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
Socialization to interdisciplinarity: Faculty and student perspectives
Socialization has become a common framework through which to understand the doctoral student experience; however, the framework has predominately been used as a lens through which to understand traditional, single-discipline doctoral student experiences. Interdisciplinary doctoral programs are becoming increasingly common in both the United States and elsewhere but relatively little empirical research exists about this distinct experience. Through multiple interviews with 18 doctoral students and their 35 faculty members, we discuss differences in the socialization process for these students in regard to knowledge acquisition, investment, and involvement. Implications for practice and future research are included
Interdisciplinary Doctoral Student Socialization
Interdisciplinary research and education are a growing emphasis in United States institutions of higher education but relatively little is known about the doctoral students engaged in these atypical programs. The purpose of this study was to understand the socialization process of 18 students involved in a large-scale, federally funded, interdisciplinary research project focused on sustainability at one university. Using Weidman, Twale, and Steinâs framework of graduate student socialization, themes emerged related to (a) their distinctive characteristics and cultures,(b) the learning process,(c) balance,(d) uncertainty, and (d) support. Recommendations for policy and practice are included
Interdisciplinary Doctoral Student Socialization
Interdisciplinary research and education are a growing emphasis in United States institutions of higher education but relatively little is known about the doctoral students engaged in these atypical programs. The purpose of this study was to understand the socialization process of 18 students involved in a large-scale, federally funded, interdisciplinary research project focused on sustainability at one university. Using Weidman, Twale, and Steinâs framework of graduate student socialization, themes emerged related to (a) their distinctive characteristics and cultures,(b) the learning process,(c) balance,(d) uncertainty, and (d) support. Recommendations for policy and practice are included
Siderophore-based microbial adaptations to iron scarcity across the eastern Pacific Ocean
Advancing the Science of Collaborative Problem Solving
Collaborative problem solving (CPS) has been receiving increasing international attention because much of the complex work in the modern world is performed by teams. However, systematic education and training on CPS is lacking for those entering and participating in the workforce. In 2015, the Programme for International Student Assessment (PISA), a global test of educational progress, documented the low levels of proficiency in CPS. This result not only underscores a significant societal need but also presents an important opportunity for psychological scientists to develop, adopt, and implement theory and empirical research on CPS and to work with educators and policy experts to improve training in CPS. This article offers some directions for psychological science to participate in the growing attention to CPS throughout the world. First, it identifies the existing theoretical frameworks and empirical research that focus on CPS. Second, it provides examples of how recent technologies can automate analyses of CPS processes and assessments so that substantially larger data sets can be analyzed and so students can receive immediate feedback on their CPS performance. Third, it identifies some challenges, debates, and uncertainties in creating an infrastructure for research, education, and training in CPS. CPS education and assessment are expected to improve when supported by larger data sets and theoretical frameworks that are informed by psychological science. This will require interdisciplinary efforts that include expertise in psychological science, education, assessment, intelligent digital technologies, and policy