Ecology of Forest Succession on a Ridge in the Subalpine Forest of Northern Colorado

This study, carried out as an addition to work already done by other workers on subalpine forests and climate, deals with the plant communities on a small ridge at between 10,000 and 11,000 feet on the East Slope of the Front Range in Boulder County, Colorado. By means of the transect method four separate forest communities were delimited: a fir stand, a limber pine stand, a mature lodgepole stand, and a young lodgepole stand. The qualitative and quantitative characters of these communities and the transition areas between them were studied; trees, shrubs, and herbs were all considered. The characters of the communities, together with some data on soil composition, light transmission, and general climate, are described and discussed. From the analysis of the stands it is concluded that: 1. All of the four communities are successional stands which have grown up after fires. All will eventually return to spruce-fir climax forest. 2. The young lodgepole community is the youngest stand. Its tardy reforestation was probably controlled by herb competition and seed destruction by rodents and birds. 3. The mature lodgepole stand and the fir stand are the same age and represent different phases of the same successional process resulting from soil moisture differences. 4. The lodgepole pine is limited in its distribution on the ridge by excessive insolation and by wind. 5. The limber pine is limited by competition. 6. The secondary vegetation of the subalpine zone and of the forest communities studied is extremely variable

Computer-assisted de-identification of free-text nursing notes

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.Includes bibliographical references (leaves 67-70).Medical researchers are legally required to protect patients' privacy by removing personally identifiable information from medical records before sharing the data with other researchers. Different computer-assisted methods are evaluated for removing and replacing protected health information (PHI) from free-text nursing notes collected in the hospital intensive care unit. A semi-automated method was developed to allow clinicians to highlight PHI on the screen of a tablet PC and to compare and combine the selections of different experts reading the same notes. Expert adjudication demonstrated that inter-human variability was high, with few false positives and many false negatives. A preliminary automated de-identification algorithm generated few false negatives but many false positives. A second automated algorithm was developed using the successful portions of the first algorithm and incorporating other heuristic methods to improve overall performance. A large de-identified collection of nursing notes was re-identified with realistic surrogate (but unprotected) dates, serial numbers, names, and phrases to form a "gold standard" reference database of over 2600 notes (approximately 340,000 words) with over 1800 labeled instances of PHI. This gold standard database of nursing notes and the Java source code used to evaluate algorithm performance will be made freely available on the Physionet web site in order to facilitate the development and validation of future de-identification algorithms.by Margaret Douglass.M.Eng

Pathways to ensure universal and affordable access to hepatitis C treatment

Direct-acting antivirals (DAAs) have dramatically changed the landscape of hepatitis C treatment and prevention. The World Health Organization has called for the elimination of hepatitis C as a public health threat by 2030. However, the discrepancy in DAA prices across low-, middle- and high-income countries is considerable, ranging from less than US$100 to approximately US$ 40,000 per course, thus representing a major barrier for the scale-up of treatment and elimination. This article describes DAA pricing and pathways to accessing affordable treatment, providing case studies from Australia, Egypt and Portugal. Pathways to accessing DAAs include developing comprehensive viral hepatitis plans to facilitate price negotiations, voluntary and compulsory licenses, patent opposition, joint procurement, and personal importation schemes. While multiple factors influence the price of DAAs, a key driver is a country's capacity and willingness to negotiate with pharmaceutical companies. If negotiations do not lead to a reasonable price, governments have the option to utilise flexibilities outlined in the Agreement on Trade-Related Aspects of Intellectual Property Rights. Affordable access to DAAs is underpinned by collaboration between government, civil society, global organisations and pharmaceutical companies to ensure that all patients can access treatment. Promoting these pathways is critical for influencing policy, improving access to affordable DAAs and achieving hepatitis C elimination

Identification of ovarian cancer metastatic miRNAs

Serous epithelial ovarian cancer (EOC) patients often succumb to aggressive metastatic disease, yet little is known about the behavior and genetics of ovarian cancer metastasis. Here, we aim to understand how omental metastases differ from primary tumors and how these differences may influence chemotherapy. We analyzed the miRNA expression profiles of primary EOC tumors and their respective omental metastases from 9 patients using miRNA Taqman qPCR arrays. We find 17 miRNAs with differential expression in omental lesions compared to primary tumors. miR-21, miR-150, and miR-146a have low expression in most primary tumors with significantly increased expression in omental lesions, with concomitant decreased expression of predicted mRNA targets based on mRNA expression. We find that miR-150 and miR-146a mediate spheroid size. Both miR-146a and miR-150 increase the number of residual surviving cells by 2–4 fold when challenged with lethal cisplatin concentrations. These observations suggest that at least two of the miRNAs, miR-146a and miR-150, up-regulated in omental lesions, stimulate survival and increase drug tolerance. Our observations suggest that cancer cells in omental tumors express key miRNAs differently than primary tumors, and that at least some of these microRNAs may be critical regulators of the emergence of drug resistant disease.<br/

Cultivating Agricultural Literacy: Challenge for the Liberal Arts

A review and analysis of 11 pacesetting experiments funded by the W. K. Kellogg Foundation to generate greater awareness among liberal arts students and faculty about the role and importance ofthe agriculture enterprise to the nation

Affine and toric hyperplane arrangements

We extend the Billera-Ehrenborg-Readdy map between the intersection lattice and face lattice of a central hyperplane arrangement to affine and toric hyperplane arrangements. For arrangements on the torus, we also generalize Zaslavsky's fundamental results on the number of regions.Comment: 32 pages, 4 figure

"Women's rights, the European Court and Supranational Constitutionalism"

This analysis examines supranational constitutionalism in the European Union. In particular, the study focuses on the role of the European Court of Justice in the creation of women’s rights. I examine the interaction between the Court and member state governments in legal integration, and also the integral role that women’s advocates – both individual activists and groups – have played in the development of EU social provisions. The findings suggest that this litigation dynamic can have the effect of fueling the integration process by creating new rights that may empower social actors and EU organizations, with the ultimate effect of diminishing member state government control over the scope and direction of EU law. This study focuses specifically on gender equality law, yet provides a general framework for examining the case law in subsequent legal domains, with the purpose of providing a more nuanced understanding of supranational governance and constitutionalism

Mitochondrial abnormalities in ageing macular photoreceptors

PURPOSE. To evaluate somatic mitochondrial (mt)DNA mutations in the macula during ageing. METHODS. Ten 30-m cryostat sections from the macula (foveal and perifoveal regions) and peripheral retina of 14 donors (aged 14 -94 years) were cut for cytochrome c oxidase cytochemistry. The photoreceptor layer was microdissected and DNA extracted for 4977-bp mtDNA (mtDNA 4977 ) quantification using PCR. Dual cytochemistry for cytochrome c oxidase and succinate dehydrogenase allowed the detection of cytochrome c oxidase-deficient cones. RESULTS. Findings showed a progressive accumulation of mtDNA 4977 from ages 14 to 94 years. From ages 14 to 60 years there was an increase from 0.006% to 0.25%, and from ages 60 to 94 years there was a steeper increase from 0.25% to 5.39%. Counts of cones in the dual-reacted preparations showed more cytochrome c oxidase-deficient cones in the foveal region than elsewhere. CONCLUSIONS. The results show that mitochondrial DNA deletions and cytochrome c oxidase-deficient cones accumulate in the ageing retina, particularly in the foveal region. These defects may contribute to the changes in macular function observed in ageing and age-related maculopathy. (Invest Ophthalmol Vis Sci. 2001;42:3016 -3022) A geing is associated with a decline in macular function, with small but significant changes in both visual acuity and contrast sensitivity evident in most elderly individuals. Morphologic changes accompanying this ageing process primarily involve the photoreceptors and the cells of the retinal pigment epithelium (RPE). This is manifested by atrophy and loss of both cell types, depigmentation and hyperpigmentation of the RPE, a progressive accumulation of lipofuscin, drusen formation, thickening of Bruch&apos;s membrane, and the appearance of basal laminar deposits