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Biotic carbon feedbacks in a materially-closed soil-vegetation-atmosphere system
The magnitude and direction of the coupled feedbacks between the biotic and abiotic components of the terrestrial carbon cycle is a major source of uncertainty in coupled climate–carbon-cycle models1, 2, 3. Materially closed, energetically open biological systems continuously and simultaneously allow the two-way feedback loop between the biotic and abiotic components to take place4, 5, 6, 7, but so far have not been used to their full potential in ecological research, owing to the challenge of achieving sustainable model systems6, 7. We show that using materially closed soil–vegetation–atmosphere systems with pro rata carbon amounts for the main terrestrial carbon pools enables the establishment of conditions that balance plant carbon assimilation, and autotrophic and heterotrophic respiration fluxes over periods suitable to investigate short-term biotic carbon feedbacks. Using this approach, we tested an alternative way of assessing the impact of increased CO2 and temperature on biotic carbon feedbacks. The results show that without nutrient and water limitations, the short-term biotic responses could potentially buffer a temperature increase of 2.3 °C without significant positive feedbacks to atmospheric CO2. We argue that such closed-system research represents an important test-bed platform for model validation and parameterization of plant and soil biotic responses to environmental changes
Warped Higgsless Models with IR--Brane Kinetic Terms
We examine a warped Higgsless model
in 5-- with IR(TeV)--brane kinetic terms. It is shown that adding a brane
term for the gauge field does not affect the scale (
TeV) where perturbative unitarity in is violated.
This term could, however, enhance the agreement of the model with the precision
electroweak data. In contrast, the inclusion of a kinetic term corresponding to
the custodial symmetry of the theory delays the unitarity violation
in scattering to energy scales of TeV for a significant
fraction of the parameter space. This is about a factor of 4 improvement
compared to the corresponding scale of unitarity violation in the Standard
Model without a Higgs. We also show that null searches for extra gauge bosons
at the Tevatron and for contact interactions at LEP II place non-trivial bounds
on the size of the IR-brane terms.Comment: 23 pages, 8 figure
Murine model for Fusarium oxysporum invasive fusariosis reveals organ-specific structures for dissemination and long-term persistence
Peer reviewedPublisher PD
Understanding young adult physical activity, alcohol and tobacco use in community colleges and 4-year post-secondary institutions: A cross-sectional analysis of epidemiological surveillance data
<p>Abstract</p> <p>Background</p> <p>Young adults experience many adverse health behavior changes as they transition from adolescence into adulthood. A better understanding of the relationships between health promoting and risky health behaviors may aid in the development of health promotion interventions for various types of young adult post-secondary students. Therefore, the purpose of this study was to examine associations between alcohol and tobacco use and physical activity among 2-year and 4-year college students.</p> <p>Methods</p> <p>Cross-sectional analyses were conducted using 2007 survey data, collected as part of an on-going post-secondary health surveillance system in Minnesota. Students were randomly selected to participant from 14 Minnesota colleges and universities (six 2-year community and/or technical colleges, eight 4-year post-secondary institutions). The 2007 surveillance data included 9,931 respondents.</p> <p>Results</p> <p>The prevalence of demographic characteristics and health behaviors (e.g., physical activity, tobacco use) differed between young adults attending 2-year and 4-year post-secondary institutions; in general, those attending 2-year institutions are representative of more at-risk populations. Overall, higher levels of moderate, vigorous and strengthening physical activity were associated with higher levels of alcohol consumption and lower levels of smoking. In general, despite the disparities in the prevalence of these risk behaviors, the associations between the behaviors did not differ substantially between 2-year and 4-year post-secondary populations.</p> <p>Conclusions</p> <p>These findings illustrate links between leading risk behaviors. Interventions targeting multiple risk behaviors among young adults may warrant further consideration. Overall, future research is needed to support and inform young adult health promotion efforts that may be implemented in a wide array of post-secondary institutions.</p
The Role of the Side Chain on the Performance of N-type Conjugated Polymers in Aqueous Electrolytes.
We report a design strategy that allows the preparation of solution processable n-type materials from low boiling point solvents for organic electrochemical transistors (OECTs). The polymer backbone is based on NDI-T2 copolymers where a branched alkyl side chain is gradually exchanged for a linear ethylene glycol-based side chain. A series of random copolymers was prepared with glycol side chain percentages of 0, 10, 25, 50, 75, 90, and 100 with respect to the alkyl side chains. These were characterized to study the influence of the polar side chains on interaction with aqueous electrolytes, their electrochemical redox reactions, and performance in OECTs when operated in aqueous electrolytes. We observed that glycol side chain percentages of >50% are required to achieve volumetric charging, while lower glycol chain percentages show a mixed operation with high required voltages to allow for bulk charging of the organic semiconductor. A strong dependence of the electron mobility on the fraction of glycol chains was found for copolymers based on NDI-T2, with a significant drop as alkyl side chains are replaced by glycol side chains
Organizational factors and depression management in community-based primary care settings
Abstract Background Evidence-based quality improvement models for depression have not been fully implemented in routine primary care settings. To date, few studies have examined the organizational factors associated with depression management in real-world primary care practice. To successfully implement quality improvement models for depression, there must be a better understanding of the relevant organizational structure and processes of the primary care setting. The objective of this study is to describe these organizational features of routine primary care practice, and the organization of depression care, using survey questions derived from an evidence-based framework. Methods We used this framework to implement a survey of 27 practices comprised of 49 unique offices within a large primary care practice network in western Pennsylvania. Survey questions addressed practice structure (e.g., human resources, leadership, information technology (IT) infrastructure, and external incentives) and process features (e.g., staff performance, degree of integrated depression care, and IT performance). Results The results of our survey demonstrated substantial variation across the practice network of organizational factors pertinent to implementation of evidence-based depression management. Notably, quality improvement capability and IT infrastructure were widespread, but specific application to depression care differed between practices, as did coordination and communication tasks surrounding depression treatment. Conclusions The primary care practices in the network that we surveyed are at differing stages in their organization and implementation of evidence-based depression management. Practical surveys such as this may serve to better direct implementation of these quality improvement strategies for depression by improving understanding of the organizational barriers and facilitators that exist within both practices and practice networks. In addition, survey information can inform efforts of individual primary care practices in customizing intervention strategies to improve depression management.http://deepblue.lib.umich.edu/bitstream/2027.42/78269/1/1748-5908-4-84.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78269/2/1748-5908-4-84-S1.PDFhttp://deepblue.lib.umich.edu/bitstream/2027.42/78269/3/1748-5908-4-84.pdfPeer Reviewe
Cervical adenocarcinoma presenting as a cardiac tamponade in a 57-year-old woman: a case report
<p>Abstract</p> <p>Introduction</p> <p>Pericardial effusion as a complication of malignant gynecological disorders is rare. Few cases of endometrial cancer, squamous cell carcinoma of the cervix, ovarian cancer and uterine carcinosarcoma have been previously reported. We report the first case of cardiac tamponade secondary to a cervical adenocarcinoma.</p> <p>Case presentation</p> <p>A 54-year-old Caucasian woman, without any relevant medical history and no gynecological aftercare, was admitted to our hospital emergency room with severe dyspnea. Echocardiography revealed severe pericardial effusion with a swinging heart. An emergency pericardial drainage was performed through a pericardial window, which permitted the draining of 700 mL of bloody fluid and a pericardial biopsy. Cytological examination of the fluid revealed atypical cells, and the biopsy specimen showed tumor emboli suggestive of adenocarcinoma. Magnetic resonance imaging showed a 35 mm cervical lesion indicative of an endocervical tumor. Exploratory laparoscopy revealed diffuse peritoneal lesions and histological examination of cervical curettage showed a poorly differentiated micropapillary adenocarcinoma of the cervix.</p> <p>Conclusion</p> <p>Carcinomatous pericarditis as the first symptom of a malignant gynecological adenocarcinoma has not, to the best of our knowledge, been documented before. This case highlights the extreme severity of pericardial effusion secondary to cervical adenocarcinoma, a sign of advanced disease. Gynecological malignancies have to be considered in cases of neoplastic pericardial effusion.</p
Aptamer-based multiplexed proteomic technology for biomarker discovery
Interrogation of the human proteome in a highly multiplexed and efficient manner remains a coveted and challenging goal in biology. We present a new aptamer-based proteomic technology for biomarker discovery capable of simultaneously measuring thousands of proteins from small sample volumes (15 [mu]L of serum or plasma). Our current assay allows us to measure ~800 proteins with very low limits of detection (1 pM average), 7 logs of overall dynamic range, and 5% average coefficient of variation. This technology is enabled by a new generation of aptamers that contain chemically modified nucleotides, which greatly expand the physicochemical diversity of the large randomized nucleic acid libraries from which the aptamers are selected. Proteins in complex matrices such as plasma are measured with a process that transforms a signature of protein concentrations into a corresponding DNA aptamer concentration signature, which is then quantified with a DNA microarray. In essence, our assay takes advantage of the dual nature of aptamers as both folded binding entities with defined shapes and unique sequences recognizable by specific hybridization probes. To demonstrate the utility of our proteomics biomarker discovery technology, we applied it to a clinical study of chronic kidney disease (CKD). We identified two well known CKD biomarkers as well as an additional 58 potential CKD biomarkers. These results demonstrate the potential utility of our technology to discover unique protein signatures characteristic of various disease states. More generally, we describe a versatile and powerful tool that allows large-scale comparison of proteome profiles among discrete populations. This unbiased and highly multiplexed search engine will enable the discovery of novel biomarkers in a manner that is unencumbered by our incomplete knowledge of biology, thereby helping to advance the next generation of evidence-based medicine
Decreased endothelin receptor B expression in large primary uveal melanomas is associated with early clinical metastasis and short survival
The most devastating aspect of cancer is the metastasis of tumour cells to organs distant from the original tumour site. The major problem facing oncologists treating uveal melanoma, the most common cancer of the eye, is metastatic disease. To lower mortality, it is necessary to increase our understanding of the molecular genetic alterations involved in this process. Using suppression subtractive hybridisation, we have analysed differential gene expression between four primary tumours from patients who have developed clinical metastasis and four primary tumours from patients with no evidence of metastasis to date. We have identified endothelin receptor type B as differentially expressed between these tumours and confirmed this observation using comparative multiplex RT–PCR. In a further 33 tumours, reduced endothelin receptor type B expression correlated with death from metastatic disease. Reduced expression also correlated with other known prognostic indicators, including the presence of epithelioid cells, chromosome 3 allelic imbalance and chromosome 8q allelic imbalance. Endothelin receptor type B expression was also reduced in four out of four primary small cell lung carcinomas compared to normal bronchial epithelium. We also show that the observed down-regulation of endothelin receptor type B in uveal melanoma was not due to gene deletion. Our findings suggest a role for endothelin receptor type B in the metastasis of uveal melanoma and, potentially, in the metastasis of other neural crest tumours
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