764 research outputs found
Malaria and land use: a spatial and temporal risk analysis in Southern Sri Lanka
Malaria / Waterborne diseases / Disease vectors / Land use / Water use / GIS / Statistical analysis / Risks / Mapping / Public health / Sri Lanka / Uda Walawe / Thanamalvila / Embilipitiya
Patterns of recurrence and survival after surgery or stereotactic radiotherapy for early stage NSCLC
IntroductionSurgery is the standard treatment for early stage non–small-cell lung cancer (NSCLC). For medically inoperable patients, stereotactic ablative radiotherapy (SABR) has emerged as widely used standard treatment. The aim of this study was to analyze survival and patterns of tumor recurrence in patients with clinical stage I NSCLC treated with surgery or SABR.MethodsClinical data from all subsequent fluoro-deoxyglucose positron emission tomography/computed tomography-based stage I NSCLC patients (cT1-T2aN0M0) treated with surgery or SABR at our center between 2007 and 2010 were collected. Primary endpoints were overall survival and tumor recurrences/new primary lung tumors. Treatment groups were compared using multivariable Cox regression and competing risk analyses.ResultsThree hundred-forty patients treated with surgery (n = 143) or SABR (n = 197) were included. Surgical patients were younger, had a better WHO performance status and less comorbidities. After adjustment for prognostic covariables, treatment did not influence overall survival (adjusted hazard ratio [HR], SABR versus surgery 1.07; 95% confidence interval [CI]: 0.74–1.54; p = 0.73). Local control and distant recurrence were equal, whereas locoregional recurrences were significantly more frequent after SABR compared with surgery (adjusted sub-HR 2.51; 95% CI: 1.10–5.70; p = 0.028). Nodal failure (HR: 2.16; 95% CI: 1.34–3.48) and distant metastases (HR: 2.12; 95% CI: 1.52–2.97), but not local failure (HR: 1.00; 95% CI: 0.53–1.89) predicted overall survival.ConclusionsIn patients with fluoro-deoxyglucose positron emission tomography/computed tomography-based stage I NSCLC, SABR confers worse locoregional tumor control because of more nodal failures compared with surgery, stressing the need to improve mediastinal and hilar staging
Fairness-enhancing interventions in stream classification
The wide spread usage of automated data-driven decision support systems has
raised a lot of concerns regarding accountability and fairness of the employed
models in the absence of human supervision. Existing fairness-aware approaches
tackle fairness as a batch learning problem and aim at learning a fair model
which can then be applied to future instances of the problem. In many
applications, however, the data comes sequentially and its characteristics
might evolve with time. In such a setting, it is counter-intuitive to "fix" a
(fair) model over the data stream as changes in the data might incur changes in
the underlying model therefore, affecting its fairness. In this work, we
propose fairness-enhancing interventions that modify the input data so that the
outcome of any stream classifier applied to that data will be fair. Experiments
on real and synthetic data show that our approach achieves good predictive
performance and low discrimination scores over the course of the stream.Comment: 15 pages, 7 figures. To appear in the proceedings of 30th
International Conference on Database and Expert Systems Applications, Linz,
Austria August 26 - 29, 201
Malaria and anaemia among children in two communities of Kumasi, Ghana: a cross-sectional survey
BACKGROUND: A survey in Kumasi, Ghana found a marked Plasmodium falciparum prevalence difference between two neighbouring communities (Moshie Zongo and Manhyia). The primary objective of this follow-up study was to determine whether this parasite rate difference was consistent over time. Secondary objectives were to compare prevalences of clinical malaria, anaemia, intestinal parasite infections, and malnutrition between these communities; and to identify potential risk factors for P. falciparum infection and anaemia. METHODS: A cross-sectional house-to-house survey of P. falciparum parasitaemia, clinical malaria, anaemia, anthropometric indices, and intestinal helminths was conducted in April-May 2005. Data collection included child and household demographics, mosquito avoidance practices, distance to nearest health facility, child's travel history, symptoms, and anti-malarial use. Risk factors for P. falciparum and anaemia (Hb < 11 g/dl) were identified using generalized linear mixed models. RESULTS: In total, 296 children were tested from 184 households. Prevalences of P. falciparum, clinical malaria, anaemia, and stunting were significantly higher in Moshie Zongo (37.8%, 16.9%, 66.2% and 21.1%, respectively) compared to Manhyia (12.8%, 3.4%, 34.5% and 7.4%). Of 197 children tested for helminths, four were positive for Dicrocoelium dendriticum. Population attributable risks (PAR%) of anaemia were 16.5% (P. falciparum) and 7.6% (malnutrition). Risk factors for P. falciparum infection were older age, rural travel, and lower socioeconomic status. Risk factors for anaemia were P. falciparum infection, Moshie Zongo residence, male sex, and younger age. CONCLUSION: Heterogeneities in malariometric indices between neighbouring Kumasi communities are consistent over time. The low helminth prevalence, and the twofold higher PAR% of anaemia attributable to P. falciparum infection compared to malnutrition, indicate the importance of malaria as a cause of anaemia in this urban population
The next generation of fibroblast-based vaccine development
Chicken embryo fibroblasts (CEF) and diploid cells have a long history in vaccine production since their isolation in the 1960s at the Wistar Institute (WI-38 cells) as well as the Medical Research Council (MRC-5 cells). The cells quickly became adopted for a number of vaccines: varicella zoster (VZV), MMR, yellow fever, polio, hepatitis A, rotavirus, rabies, Marek\u27s disease, and dengue virus. Most of these vaccine processes were developed with classical media supplemented with Fetal Bovine Serum (FBS). The Hayflick limit of diploid cells restricted their adaptation to a serum-free process. While some of the vaccines such as polio and rabies have been transitioned to Vero cells, several vaccines continue to be manufactured with CEF and human diploid cells. Currently, FBS from Australia and New Zealand are utilized for the highest level of patient safety for human vaccines. However, this supply of serum is challenged by two factors: growth of existing vaccines to improve global access and the development of new gene therapies that require FBS. In order to reduce dependency on serum, we initiated a medium development program. Using metabolite analysis and DOE, we have developed a serum-reduced growth medium and a serum-free virus production medium for MRC-5 and other fibroblast cells. With a serum reduction of 90-100%, the growth medium can support direct recovery from thaw and adaptation-free expansion, resulting in performance that is comparable to classical medium with 10% serum. We confirmed virus production with VZV and vesicular stomatitis virus in MRC-5 cells as well as Marek’s disease virus in CEFs and demonstrate a higher specific productivity. By switching to a low serum process, vaccine manufacturers can reduce production and purification costs, and increase product consistency and safety
Resource Wars and Conflict Ivory: The Impact of Civil Conflict on Elephants in the Democratic Republic of Congo - The Case of the Okapi Reserve
Human conflict generally has substantial negative impacts on wildlife and conservation. The recent civil war (1995-2006) in the Democratic Republic of Congo (DRC) resulted in a significant loss of wildlife, including elephants, due to institutional collapse, lawlessness and unbridled exploitation of natural resources such as minerals, wood, ivory and bushmeat. We used data from distance sampling surveys conducted before and after the war in a protected forest, the Okapi Faunal Reserve, to document changes in elephant abundance and distribution. We employed Generalized Additive Models to relate changes in elephant distribution to human and environmental factors. Populations declined by nearly fifty percent coinciding with a major increase in elephant poaching as indicated by reports of ivory trade during the war. Our results suggest that humans influenced elephant distribution far more than habitat, both before and after the war, but post-war models explained more of the variation. Elephant abundance declined more, closer to the park boundary and to areas of intense human activity. After the war, elephant densities were relatively higher in the centre of the park where they were better protected, suggesting that this area may have acted as a refuge. In other sites in Eastern DRC, where no protection was provided, elephants were even more decimated. Post-war dynamics, such as weakened institutions, human movements and availability of weapons, continue to affect elephants. Survival of remaining populations and recovery will be determined by these persistent factors and by new threats associated with growing human populations and exploitation of natural resources. Prioritizing wildlife protection, curbing illegal trade in ivory and bushmeat, and strengthening national institutions and organizations in charge of conservation will be crucial to counter these threats
Modelization of flow electrification in a polymer melt
Flow electrification of polymer melts is an important side effect of polymer
processing. The studies dealing with this phenomenon are seldom and most of the
scientific work has been focused on flow electrification of aqueous and
insulating Newtonian liquids. From that prior art it is well established that
the flow electrification in Newtonian liquids is a consequence of the formation
of an ionic double layer. Convection of this layer induces the electrification
of the liquid at the outlet of the pipe. In those models, the key parameters
governing the flow electrification are thus the intrinsic electrical properties
of the polymer and the flow characteristics. In this work, we reconsider the
assumptions made previously and we propose a new approach to modelise the flow
electrification in the particular case of non-Newtonian polymer materials in
laminar flow conditions. We establish that, a key parameter for the
electrification quantification in the polymer melt is the shape of the velocity
profile. Additionally, in some cases, we show that a slip velocity at the
polymer/die wall interface must be considered to describe accurately the
electrification. As a consequence, we deduce that the slip velocity at the
interface can be calculated by measuring the electrification: this work gives
an alternative manner to measure the slip velocity during polymer flow
PIN6 is required for nectary auxin response and short stamen development
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98417/1/tpj12184-sup-0001-FigS1.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/98417/2/tpj12184.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/98417/3/tpj12184-sup-0004-FigS4.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/98417/4/tpj12184-sup-0003-FigS3.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/98417/5/tpj12184-sup-0002-FigS2.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/98417/6/tpj12184-sup-0005-FigS5.pd
Primary skin fibroblasts as a model of Parkinson's disease
Parkinson's disease is the second most frequent neurodegenerative disorder. While most cases occur sporadic mutations in a growing number of genes including Parkin (PARK2) and PINK1 (PARK6) have been associated with the disease. Different animal models and cell models like patient skin fibroblasts and recombinant cell lines can be used as model systems for Parkinson's disease. Skin fibroblasts present a system with defined mutations and the cumulative cellular damage of the patients. PINK1 and Parkin genes show relevant expression levels in human fibroblasts and since both genes participate in stress response pathways, we believe fibroblasts advantageous in order to assess, e.g. the effect of stressors. Furthermore, since a bioenergetic deficit underlies early stage Parkinson's disease, while atrophy underlies later stages, the use of primary cells seems preferable over the use of tumor cell lines. The new option to use fibroblast-derived induced pluripotent stem cells redifferentiated into dopaminergic neurons is an additional benefit. However, the use of fibroblast has also some drawbacks. We have investigated PARK6 fibroblasts and they mirror closely the respiratory alterations, the expression profiles, the mitochondrial dynamics pathology and the vulnerability to proteasomal stress that has been documented in other model systems. Fibroblasts from patients with PARK2, PARK6, idiopathic Parkinson's disease, Alzheimer's disease, and spinocerebellar ataxia type 2 demonstrated a distinct and unique mRNA expression pattern of key genes in neurodegeneration. Thus, primary skin fibroblasts are a useful Parkinson's disease model, able to serve as a complement to animal mutants, transformed cell lines and patient tissues
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