4,143 research outputs found
A Lightweight Policy System for Body Sensor Networks
Body sensor networks (BSNs) for healthcare have more stringent security and context adaptation requirements than required in large-scale sensor networks for environment monitoring. Policy-based management enables flexible adaptive behavior by supporting dynamic loading, enabling and disabling of policies without shutting down nodes. This overcomes many of the limitations of sensor operating systems, such as TinyOS, which do not support dynamic modification of code. Alternative schemes for adaptation, such as network programming, have a high communication cost and suffer from operational interruption. In addition, a policy-driven approach enables finegrained access control through specifying authorization policies. This paper presents the design, implementation and evaluation of an efficient policy system called Finger which enables policy interpretation and enforcement on distributed sensors to support sensor level adaptation and fine-grained access control. It features support for dynamic management of policies, minimization of resources usage, high responsiveness and node autonomy. The policy system is integrated as a TinyOS component, exposing simple, well-defined interfaces which can easily be used by application developers. The system performance in terms of processing latency and resource usage is evaluated. © 2009 IEEE.Published versio
Extra-hepatic fascioliasis with peritoneal malignancy tumor feature
Fascioliasis is a zoonose parasitic disease
caused by Fasciola hepatica and Fasciola gigantica and is
widespread in most regions of the world. Ectopic fascioliasis
usually caused by juvenile Fasciola spp., but in
recent years a few cases of tissue-embedded ova have been
reported from different endemic areas. A 79-year-old Iranian
man resident in Eird-e-Mousa village from Ardabil
Province, north-west of Iran, complained with abdominal
pain, nausea, and intestinal obstruction symptoms referred
to Ardabil Fatemi hospital. In laparotomy multiple intestinal
masses with peritoneal seeding resembling of a
malignant lesion were seen. After appendectomy and peritoneal
mass biopsy with numerous intraperitoneal adenopathy,
paraffin embedded blocks were prepared from
each tissues. A blood sample was taken from the patient
5 months later for serological diagnosis. Histopathological
examination of sections showed fibrofatty stroma with
dense mixed inflammatory cells infiltration and fibrosis in
peritoneal masses. Large numbers of ova of Fasciola spp.
were noted with typical circumscribed granulomas. Despite
of anti-fasciola treatment, IHA test for detecting anti F.
hepatica antibodies was positive 5 months after surgery
with a titer of 1/128. Due to multiple clinical manifestation
of extra-hepatic fascioliasis, its differential diagnosis from
intraperitoneal tumors or other similar diseases should be
considered
Simply-supported multi-layered beams for energy harvesting
This paper develops an analytical model for predicting the performance of simply-supported multi-layered piezoelectric vibrating energy harvesters. The model includes the effects of material and geometric nonlinearities, as well as axial pre-tension/compression, and is validated against experimental devices for a large range of base accelerations. Numerical and experimental investigations are performed to understand the benefits of using simply supported devices compared to cantilevered devices. Comparisons are made in an unbiased manner by tuning the resonant frequency to the same value by modifying the geometry, and the results obtained indicate that simply supported devices are capable of generating higher voltage levels than cantilever devices. The model is also used to investigate the benefits of using multi-layered devices to improve power density. Depending on harvester composition, power-per-unit-volume of piezoelectric material for a device is increased through the stacking of layers
A decision support system for water quality issues in the Manzanares River (Madrid, Spain)
The Manzanares River, located in Madrid (Spain), is the main water supplier of a highly populated region,
and it also receives wastewater from the same area. The effluents of eight Waste Water Treatment Plants
(WWTPs) downstream of the river, which represent 90% of the flow in the middle and lower parts of the
river, are the primary sources of water pollution. Although the situation has improved slightly in the last two
years, the water in the river is highly polluted, making it uninhabitable for aquatic life. Water quality
modelling is typically used to assess the effect of treatment improvements in water bodies. In this work, the
GESCAL module of the Aquatool Decision Support System Shell was used to simulate water quality in the
Manzanares River. GESCAL is appropriate for modelling in an integrated way water quality for whole water
resources systems, including reservoirs and rivers. A model was built that simulates conductivity,
phosphorous, carbonaceous organic matter, dissolved oxygen, organic nitrogen, ammonia, and nitrates.
The period from October 2006 to September 2008 was selected for calibration due to the many treatment
modifications that occurred during this time. An earlier and longer period, from October 2000 to September
2006, was used for validation. In addition, a daily model was used to analyse the robustness of the GESCAL
model. Once the GESCAL model was validated, different scenarios were considered and simulated. First,
different combinations of nutrient elimination among the different WWTPs were simulated, leading to the
conclusion that investments have to focus on three of the proposed WWTPs. Moreover, these treatments will
not be sufficient to maintain fish habitat conditions at all times. Additional measures, such as the increment
of the flow in the river or oxygen injection, were simulated. Incrementing the flow of the Manzanares River
has been shown to be an efficient means of increasing water quality, but this implies an increment in the risk
of water scarcity situations in the Madrid water supply system.
© 2010 Elsevier B.V. All rights reserved.This work has been supported by the Spanish Ministry of Science and Innovation through the project Consolider-Ingenio 2010 CSD2009-00065.Paredes Arquiola, J.; Andreu Álvarez, J.; Solera Solera, A. (2010). A decision support system for water quality issues in the Manzanares River (Madrid, Spain). Science of the Total Environment. 408:2576-2589. https://doi.org/10.1016/j.scitotenv.2010.02.037S2576258940
Reproductive hormone analyses and effects of adjuvant zoledronic acid in early breast cancer – an AZURE (BIG 01/04) sub-study
Purpose: Adjuvant bisphosphonates have been shown to improve disease outcomes in early breast cancer in women who are postmenopausal at the start of treatment. We explored the influence of pretreatment serum levels of reproductive hormones in the hypothalamic-pituitary-gonadal (HPG) axis from a subset of patients included in the AZURE trial to investigate their impact on disease recurrence and whether reproductive hormone measurements are of value in selecting patients for treatment with adjuvant zoledronic acid. Patients and methods: The AZURE trial is an academic, multi-centre, international phase III trial that randomised patients to standard adjuvant therapy (chemotherapy and/or endocrine therapy) +/- intravenous zoledronic acid, 4 mg for 5 years. Serum from 865 patients taken at randomisation was stored at -80°C prior to central batch analysis for inhibin A, oestradiol and follicle stimulating hormone (FSH). We assessed the clinical value of pretreatment hormone levels for predicting invasive disease free survival (IDFS), skeletal recurrence and distant recurrence and response to treatment with zoledronic acid. Results: Oestradiol in the postmenopausal range (26IU/l) was associated with a longer time to bone as first recurrence (HR 0.66 95%CI: 0.41–1.04 p=0.072) compared to an FSH ≤26IU/l. When all 3 hormone levels were within the assay specified postmenopausal range, a trend to improved IDFS was seen with addition of zoledronic acid in biochemically postmenopausal women only (postmenopausal HR=0.81; 95%CI: 0.54–1.22, non-postmenopausal HR=0.99; 95%CI: 0.69–1.39) with risk reductions that mirrored the results of the main AZURE study, although the interaction between menopausal status and treatment effect was not statistically significant (p=0.47). Conclusion: Oestradiol and FSH may influence the pattern of disease recurrence with postmenopausal levels possibly creating a less conducive environment for the formation of bone metastases, therefore disseminated tumour cells could seek alternative niches outside of bone. Biochemical evaluation of a panel of reproductive hormones may be helpful to assist selection of patients for adjuvant zoledronic acid when menopausal status is unknown
Detection of regulator genes and eQTLs in gene networks
Genetic differences between individuals associated to quantitative phenotypic
traits, including disease states, are usually found in non-coding genomic
regions. These genetic variants are often also associated to differences in
expression levels of nearby genes (they are "expression quantitative trait
loci" or eQTLs for short) and presumably play a gene regulatory role, affecting
the status of molecular networks of interacting genes, proteins and
metabolites. Computational systems biology approaches to reconstruct causal
gene networks from large-scale omics data have therefore become essential to
understand the structure of networks controlled by eQTLs together with other
regulatory genes, and to generate detailed hypotheses about the molecular
mechanisms that lead from genotype to phenotype. Here we review the main
analytical methods and softwares to identify eQTLs and their associated genes,
to reconstruct co-expression networks and modules, to reconstruct causal
Bayesian gene and module networks, and to validate predicted networks in
silico.Comment: minor revision with typos corrected; review article; 24 pages, 2
figure
Back reaction, emission spectrum and entropy spectroscopy
Recently, an interesting work, which reformulates the tunneling framework to
directly produce the Hawking emission spectrum and entropy spectroscopy in the
tunneling picture, has been received a broad attention. However, during the
emission process, most related observations have not incorporated the effects
of back reaction on the background spacetime, whose derivations are therefore
not the desiring results for the real physical process. With this point as a
central motivation, in this paper we suitably adapt the \emph{reformulated}
tunneling framework so that it can well accommodate the effects of back
reaction to produce the Hawking emission spectrum and entropy spectroscopy.
Consequently, we interestingly find that, when back reaction is considered, the
Parikh-Wilczek's outstanding observations that, an isolated radiating black
hole has an unitary-evolving emission spectrum that is \emph{not} precisely
thermal, but is related to the change of the Bekenstein-Hawking entropy, can
also be reproduced in the reformulated tunneling framework, meanwhile the
entropy spectrum has the same form as that without inclusion of back reaction,
which demonstrates the entropy quantum is \emph{independent} of the effects of
back reaction. As our final analysis, we concentrate on the issues of the black
hole information, but \emph{unfortunately} find that, even including the
effects of back reaction and higher-order quantum corrections, such tunneling
formalism can still not provide a mechanism for preserving the black hole
information.Comment: 16 pages, no figure, use JHEP3.cls. to be published in JHE
Honeybee Colony Vibrational Measurements to Highlight the Brood Cycle
Insect pollination is of great importance to crop production worldwide and honey bees are amongst its chief facilitators. Because of the decline of managed colonies, the use of sensor technology is growing in popularity and it is of interest to develop new methods which can more accurately and less invasively assess honey bee colony status. Our approach is to use accelerometers to measure vibrations in order to provide information on colony activity and development. The accelerometers provide amplitude and frequency information which is recorded every three minutes and analysed for night time only. Vibrational data were validated by comparison to visual inspection data, particularly the brood development. We show a strong correlation between vibrational amplitude data and the brood cycle in the vicinity of the sensor. We have further explored the minimum data that is required, when frequency information is also included, to accurately predict the current point in the brood cycle. Such a technique should enable beekeepers to reduce the frequency with which visual inspections are required, reducing the stress this places on the colony and saving the beekeeper time
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