408 research outputs found
Automated monitoring of tweets for early detection of the 2014 Ebola epidemic
First reported in March 2014, an Ebola epidemic impacted West Africa, most notably Liberia, Guinea and Sierra Leone. We demonstrate the value of social media for automated surveillance of infectious diseases such as the West Africa Ebola epidemic. We experiment with two variations of an existing surveillance architecture: the first aggregates tweets related to different symptoms together, while the second considers tweets about each symptom separately and then aggregates the set of alerts generated by the architecture. Using a dataset of tweets posted from the affected region from 2011 to 2014, we obtain alerts in December 2013, which is three months prior to the official announcement of the epidemic. Among the two variations, the second, which produces a restricted but useful set of alerts, can potentially be applied to other infectious disease surveillance and alert systems
Measurements of the Composite Fermion masses from the spin polarization of 2-D electrons in the region
Measurements of the reflectivity of a 2-D electron gas are used to deduce the
polarization of the Composite Fermion hole system formed for Landau level
occupancies in the regime 1<\nu<2. The measurements are consistent with the
formation of a mixed spin CF system and allow the density of states or
`polarization' effective mass of the CF holes to be determined. The mass values
at \nu=3/2 are found to be ~1.9m_{e} for electron densities of 4.4 x 10^{11}
cm^{-2}, which is significantly larger than those found from measurements of
the energy gaps at finite values of effective magnetic field.Comment: 4 pages, 3 fig
Neuroblastomas with chromosome 11q loss and single copy MYCN comprise a biologically distinct group of tumours with adverse prognosis
Neuroblastoma is a heterogeneous tumour and its effective clinical management is dependent on accurate prognostic evaluation. In approximately 25% of patients amplification of the MYCN oncogene is known to be associated with a poor outcome. In order to identify additional molecular markers with prognostic potential in non-MYCN-amplified neuroblastomas, we looked for a correlation between clinical outcome and loss of heterozygosity (LOH) on four chromosomes that frequently show alteration in neuroblastoma (chromosomes 3, 4, 11 and 14). Chromosome 11q loss (with frequent parallel loss of chromosomes 3p, 4p and/or 14q) was found exclusively in tumours without MYCN amplification and was significantly associated with poor event-free survival. The 2-year event-free survival rate for 11q LOH cases was 30%, compared to 34% for MYCN-amplified cases and 100% for cases without these abnormalities. While 11q LOH was associated predominantly with advanced-stage disease, 2 cases with low-stage disease and 11q LOH both suffered relapses. We conclude that chromosome 11q loss defines a biologically distinct group of tumours without MYCN amplification that appear to have potential for aggressive metastatic growth. Thus this genetic alteration may be an important new prognostic marker in neuroblastoma. © 2001 Cancer Research Campaign http://www.bjcancer.co
Pulmonary function measures predict mortality differently in IPF versus combined pulmonary fibrosis and emphysema
The composite physiologic index (CPI) was derived to represent the extent of
fibrosis on high-resolution computed tomography (HRCT), adjusting for emphysema in patients
with idiopathic pulmonary fibrosis (IPF). We hypothesised that longitudinal change in CPI would
better predict mortality than forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) or
diffusing capacity of the lung for carbon monoxide (DLCO) in all patients with IPF, and especially
in those with combined pulmonary fibrosis and emphysema (CPFE).
Cox proportional hazard models were performed on pulmonary function data from IPF patients at
baseline (n=321), 6 months (n=211) and 12 months (n=144). Presence of CPFE was determined by
HRCT.
A five-point increase in CPI over 12 months predicted subsequent mortality (HR 2.1, p=0.004). At
12 months, a 10% relative decline in FVC, a 15% relative decline in DLCO or an absolute increase in
CPI of five points all discriminated median survival by 2.1 to 2.2 yrs versus patients with lesser
change. Half our cohort had CPFE. In patients with moderate/severe emphysema, only a 10%
decline in FEV1 predicted mortality (HR 3.7, p=0.046).
In IPF, a five-point increase in CPI over 12 months predicts mortality similarly to relative
declines of 10% in FVC or 15% in DLCO. For CPFE patients, change in FEV1 was the best predictor
of mortality.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91949/1/2011 ERJ - Pulmonary function measures predict mortality differently in IPF versus combined pulmonary fibrosis and emphysema.pd
Summertime carbonaceous aerosols collected in the marine boundary layer of the Arctic Ocean
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95484/1/jgrd13027.pd
Phosphate modification of calcium aluminate cement to enhance stability for immobilisation of metallic wastes
Cementing systems based on calcium aluminate cement (CAC) have been studied as an alternative cement matrix for the encapsulation of intermediate level wastes (ILWs) arising from the nuclear industry. Calcium aluminate cement based systems have great potential for the incorporation of aluminium containing ILW owing to the near neutral internal pH of these binders. However, CAC based binders usually undergo phase conversion from the metastable hydration phases C3AH6 and/or C2AH8 to the stable C3AH6, resulting in strength regression and dimensional instability. The present study investigates the feasibility of CAC modification to prevent this detrimental process of phase conversion. Two different types of sodium phosphates are used to modify a CAC system, and the setting behaviour and the mineralogy of the binder products were studied. It is shown that it is possible to avoid the conventional phase conversion of CAC hydrates due to the formation of an amorphous aluminate phase in place of the metastable hydrates, leading to the production of a phase assemblage, which is stable for at least 180 days
Met synergizes with p53 loss to induce mammary tumors that possess features of claudin-low breast cancer
Triple-negative breast cancers lack targeted therapies and are subdivided into molecular subtypes, including basal and claudin-low. Preclinical models representing these subtypes are limited. We have developed a murine model in which mammary gland expression of a receptor tyrosine kinase (MET) and loss of tumor suppressor gene p53 (Trp53), synergize to promote tumors with pathological and molecular features of claudin-low breast cancer. These tumors require MET signaling for proliferation, as well as mesenchymal characteristics, which are key features of claudin-low biology. This work associates MET expression and p53 loss with claudin-low breast cancers and highly proliferative breast cancers of poor outcome
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