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31.
Ivan Valiela Coralie Barth-Jensen Thomas Stone John Crusius Sophia Fox Megan Bartholomew 《Biogeochemistry》2013,115(1-3):299-315
A series of eight watersheds on the Pacific coast of Panama where conversion of mature lowland wet forest to pastures by artisanal burning provided watershed-scale experimental units with a wide range of forest cover (23, 29, 47, 56, 66, 73, 73, 91, and 92 %). We used these watersheds as a landscape-scale experiment to assess effects of degree of deforestation on within-watershed retention and hydrological export of atmospheric inputs of nutrients. Retention was estimated by comparing rainfall nutrient concentrations (volume-weighted to allow for evapotranspiration) to concentrations in freshwater reaches of receiving streams. Retention of rain-derived nutrients in these Panama watersheds averaged 77, 85, 80, and 62 % for nitrate, ammonium, dissolved organic N, and phosphate, respectively. Retention of rain-derived inorganic nitrogen, however, depended on watershed cover: retention of nitrate and ammonium in pasture-dominated watersheds was 95 and 98 %, while fully forested watersheds retained 65 and 80 % of atmospheric nitrate and ammonium inputs. Watershed forest cover did not affect retention of dissolved organic nitrogen and phosphate. Exports from more forested watersheds yielded DIN/P near 16, while pasture-dominated watersheds exported N/P near 2. The differences in magnitude of exports and ratios suggest that deforestation in these Panamanian forests results in exports that affect growth of plants and algae in the receiving stream and estuarine ecosystems. Watershed retention of dissolved inorganic nitrogen calculated from wet plus dry atmospheric deposition varied from 90 % in pasture- to 65 % in forest-dominated watersheds, respectively. Discharges of DIN to receiving waters from the watersheds therefore rose from 10 % of atmospheric inputs for pasture-dominated watersheds, to about 35 % of atmospheric inputs for fully forested watersheds. These results from watersheds with no agriculture or urbanization, but different conversion of forest to pasture by burning, show significant, deforestation-dependent retention within tropical watersheds, but also ecologically significant, and deforestation-dependent, exports that are biologically significant because of the paucity of nutrients in receiving tropical stream and coastal waters. 相似文献
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Martin Lappann Sophia Danhof Frank Guenther Silvana Olivares‐Florez Ines Louise Mordhorst Ulrich Vogel 《Molecular microbiology》2013,89(3):433-449
Neisseria meningitidis (Nm) is a leading cause of septicemia in childhood. Nm septicemia is unique with respect to very quick disease progression, high in vivo bacterial replication rate and its considerable mortality. Nm circumvents major mechanisms of innate immunity such as complement system and phagocytosis. Neutrophil extracellular traps (NETs) are formed from neutrophils during systemic infection and are suggested to contain invading microorganisms. Here, we investigated the interaction of Nm with NETs. Both, meningococci and spontaneously released outer membrane vesicles (SOMVs) were potent NET inducers. NETs were unable to kill NET bound meningococci, but slowed down their proliferation rate. Using Nm as model organism we identified three novel mechanisms how bacteria can evade NET‐mediated killing: (i) modification of lipid A of meningococcal LPS with phosphoethanolamine protected Nm from NET‐bound cathepsin G; (ii) expression of the high‐affinity zinc uptake receptor ZnuD allowed Nm to escape NET‐mediated nutritional immunity; (iii) binding of SOMVs to NETs saved Nm from NET binding and the consequent bacteriostatic effect. Escape from NETs may contribute to the most rapid progression of meningococcal disease. The induction of NET formation by Nm in vivo might aggravate thrombosis in vessels ultimately directing to disseminated intravascular coagulation (DIC). 相似文献
34.
Theodoros Skevas Scott M. Swinton Sophia Tanner Gregg Sanford Kurt D. Thelen 《Global Change Biology Bioenergy》2016,8(6):1162-1177
Perennial, cellulosic bioenergy crops represent a risky investment. The potential for adoption of these crops depends not only on mean net returns, but also on the associated probability distributions and on the risk preferences of farmers. Using 6‐year observed crop yield data from highly productive and marginally productive sites in the southern Great Lakes region and assuming risk neutrality, we calculate expected breakeven biomass yields and prices compared to corn (Zea mays L.) as a benchmark. Next we develop Monte Carlo budget simulations based on stochastic crop prices and yields. The crop yield simulations decompose yield risk into three components: crop establishment survival, time to maturity, and mature yield variability. Results reveal that corn with harvest of grain and 38% of stover (as cellulosic bioenergy feedstock) is both the most profitable and the least risky investment option. It dominates all perennial systems considered across a wide range of farmer risk preferences. Although not currently attractive for profit‐oriented farmers who are risk neutral or risk averse, perennial bioenergy crops have a higher potential to successfully compete with corn under marginal crop production conditions. 相似文献
35.
Phosphoproteome analysis of the MAPK pathway reveals previously undetected feedback mechanisms 下载免费PDF全文
Florian Gnad Sophia Doll Kyung Song Matthew P. Stokes John Moffat Bonnie Liu David Arnott Jeffrey Wallin Lori S. Friedman Georgia Hatzivassiliou Marcia Belvin 《Proteomics》2016,16(14):1998-2004
The RAS‐RAF‐MEK‐ERK (MAPK) pathway is prevalently perturbed in cancer. Recent large‐scale sequencing initiatives profiled thousands of tumors providing insight into alterations at the DNA and RNA levels. These efforts confirmed that key nodes of the MAPK pathway, in particular KRAS and BRAF, are among the most frequently altered proteins in cancer. The establishment of targeted therapies, however, has proven difficult. To decipher the underlying challenges, it is essential to decrypt the phosphorylation network spanned by the MAPK core axis. Using mass spectrometry we identified 2241 phosphorylation sites on 1020 proteins, and measured their responses to inhibition of MEK or ERK. Multiple phosphorylation patterns revealed previously undetected feedback, as upstream signaling nodes, including receptor kinases, showed changes at the phosphorylation level. We provide a dataset rich in potential therapeutic targets downstream of the MAPK cascade. By integrating TCGA (The Cancer Genome Atlas) data, we highlight some downstream phosphoproteins that are frequently altered in cancer. All MS data have been deposited in the ProteomeXchange with identifier PXD003908 ( http://proteomecentral.proteomexchange.org/dataset/PXD003908 ). 相似文献
36.
Marlène Jagut Patricia Hamminger Alexander Woglar Sophia Millonigg Luis Paulin Martin Mikl Maria Rosaria Dello Stritto Lois Tang Cornelia Habacher Angela Tam Miguel Gallach Arndt von Haeseler Anne M. Villeneuve Verena Jantsch 《PLoS biology》2016,14(3)
During the first meiotic division, crossovers (COs) between homologous chromosomes ensure their correct segregation. COs are produced by homologous recombination (HR)-mediated repair of programmed DNA double strand breaks (DSBs). As more DSBs are induced than COs, mechanisms are required to establish a regulated number of COs and to repair remaining intermediates as non-crossovers (NCOs). We show that the Caenorhabditis elegans RMI1 homolog-1 (RMH-1) functions during meiosis to promote both CO and NCO HR at appropriate chromosomal sites. RMH-1 accumulates at CO sites, dependent on known pro-CO factors, and acts to promote CO designation and enforce the CO outcome of HR-intermediate resolution. RMH-1 also localizes at NCO sites and functions in parallel with SMC-5 to antagonize excess HR-based connections between chromosomes. Moreover, RMH-1 also has a major role in channeling DSBs into an NCO HR outcome near the centers of chromosomes, thereby ensuring that COs form predominantly at off-center positions. 相似文献
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Agnes Y. Lai Moses W. Mui Alice Wan Sunita M. Stewart Carol Yew Tai-hing Lam Sophia S. Chan 《PloS one》2016,11(1)
Evidence-based practice and capacity-building approaches are essential for large-scale health promotion interventions. However, there are few models in the literature to guide and evaluate training of social service workers in community settings. This paper presents the development and evaluation of the “train-the-trainer” workshop (TTT) for the first large scale, community-based, family intervention projects, entitled “Happy Family Kitchen Project” (HFK) under the FAMILY project, a Hong Kong Jockey Club Initiative for a Harmonious Society. The workshop aimed to enhance social workers’ competence and performance in applying positive psychology constructs in their family interventions under HFK to improve family well-being of the community they served. The two-day TTT was developed and implemented by a multidisciplinary team in partnership with community agencies to 50 social workers (64% women). It focused on the enhancement of knowledge, attitude, and practice of five specific positive psychology themes, which were the basis for the subsequent development of the 23 family interventions for 1419 participants. Acceptability and applicability were enhanced by completing a needs assessment prior to the training. The TTT was evaluated by trainees’ reactions to the training content and design, changes in learners (trainees) and benefits to the service organizations. Focus group interviews to evaluate the workshop at three months after the training, and questionnaire survey at pre-training, immediately after, six months, one year and two years after training were conducted. There were statistically significant increases with large to moderate effect size in perceived knowledge, self-efficacy and practice after training, which sustained to 2-year follow-up. Furthermore, there were statistically significant improvements in family communication and well-being of the participants in the HFK interventions they implemented after training. This paper offers a practical example of development, implementation and model-based evaluation of training programs, which may be helpful to others seeking to develop such programs in diverse communities. 相似文献
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Barth Oeseburg Jos Schols Marcel Olde Rikkert Henriëtte van der Horst Dini Smilde-van den Doel Sophia de Rooij Bianca Buurman-van Es Marieke Schuurmans Jacobijn Gussekloo 《Tijdschrift voor gerontologie en geriatrie》2016,47(6):272-281
The Netherlands Organisation of Health Research and Development started in 2008 the Dutch National Care for the Elderly Programme (in Dutch abbreviated as NPO) with the aim to improve the quality of life for the frail older people through better quality of care (health, social, community) which is tailored to the needs and wants of older people. The delivery of good care is related with competent professional behaviour which is inextricably linked to the education of professionals. This article presents an overview of 32 educational programmes developed within the NPO. Within the NPO different educational programmes were developed on relevant themes to improve elderly care. However, the programmes focused mainly on professionals in health care, especially those working in primary care. For nurses and nursing assistants and more or less for physicians also different educational programmes were developed. Educational programmes for paramedics or professionals working in social care, housing or in the municipalities were scarce. This is also the case for specific themes in elderly care like loneliness or (domestic) violence. Moreover, none of the experiments focused on older people or informal care givers. Although 22 of the 32 projects developed educational programmes for different groups, multi – or interdisciplinary education is rare in these programmes. Based on the overview we advise the development of more educational programmes on: target groups which were less or not addressed in the NPO, like professionals in social care and paramedics; multi- or interdisciplinary collaboration; and themes, like loneliness in older people and elder abuse. 相似文献