138 research outputs found
A Markov Chain Approach to Damage Evolution in Die-Cast ZAMAK
ZAMAK components typically have a high load-bearing capacity but show large variations in their limit loads and in the number of life cycles they can sustain. In this paper a new stochastic approach to account for accumulated damage is resented where weakening effects, such as impurities, pores and cracks, are considered as distributed defects and a Markov process is used to model the defect evolution. The basic ideas of this stochastic model are presented and sample calculations on die-cast ZAMAK components illustrate the field of application and the versatility of this approach
Concurrent chemoradiotherapy in limited-stage small-cell lung cancer. Results of a pilot study
Between January 1994 and February 1998, 32, limited-stage small-cell lung cancer patients were treated with concurrent chemoradiotherapy. Follow-up time ranged from 4 to 34 months, (median 14 months). Complete regression was obtained in 22 of the 30 patients, who received at least four courses of EP chemotherapy and a tumour dose of 50 Gy or more. In all, 2-year actuarial disease-free survival was 21 %. Brain metastases occurred in 8 (36.4 %) patients with CR, in 5/7 (71.4 %) patients without prophylactic cranial irradiation (PCI) and in 3/15 (20 %) patients after PCI. The survival rate was lower in patients with PCI, in Whom chest irradiation was started later than one month from the beginning of course 1 of EP chemotherapy. We have suggested a modification of the treatment protocol
TabAttention: Learning Attention Conditionally on Tabular Data
Medical data analysis often combines both imaging and tabular data processing
using machine learning algorithms. While previous studies have investigated the
impact of attention mechanisms on deep learning models, few have explored
integrating attention modules and tabular data. In this paper, we introduce
TabAttention, a novel module that enhances the performance of Convolutional
Neural Networks (CNNs) with an attention mechanism that is trained
conditionally on tabular data. Specifically, we extend the Convolutional Block
Attention Module to 3D by adding a Temporal Attention Module that uses
multi-head self-attention to learn attention maps. Furthermore, we enhance all
attention modules by integrating tabular data embeddings. Our approach is
demonstrated on the fetal birth weight (FBW) estimation task, using 92 fetal
abdominal ultrasound video scans and fetal biometry measurements. Our results
indicate that TabAttention outperforms clinicians and existing methods that
rely on tabular and/or imaging data for FBW prediction. This novel approach has
the potential to improve computer-aided diagnosis in various clinical workflows
where imaging and tabular data are combined. We provide a source code for
integrating TabAttention in CNNs at
https://github.com/SanoScience/Tab-Attention.Comment: Accepted for the 26th International Conference on Medical Image
Computing and Computer Assisted Intervention (MICCAI) 202
The role of accelerated hyperfractionated radiotherapy in the treatment of inoperable non-small celi lung cancer: a controlled clinical trial
Prioritization of mycotoxins for risk management action based on both public health risk and mitigation efficacy
There is a large and progressively growing number of mycotoxins with new potential concerns and implications on consumer protection. The classical approach to risk management is to deal with each emerging hazard individually, leading to both overload and lack of coherence in terms of an overall riskbased approach. The development of mitigation strategies should prioritize mycotoxins that regularly
occur at undesirable levels in commonly consumed commodities, wherein both the toxicological profiles and effectiveness of mitigation are understood with a reasonable degree of certainty. The ultimate goal of mycotoxin mitigation is to prevent adverse health effects caused by foodborne exposure to mycotoxins, while preserving nutritional and organoleptic quality of food. The International Life Sciences Institute Europe (ILSI Europe) Food Contaminants Task Force is firmly committed to contributing to the understanding of the issues of mycotoxins affecting the different points of the food chain.
This presentation will illustrate a recent new activity that is devoted to establishing a framework for the prioritization of mycotoxins found in food following a risk-based approach (decision tree). Based on the evidence and scale of risk to consumers, and the potential for risk mitigation, the framework will enable the differentiation between mycotoxins where risk management action is both warranted and likely to be effective based on available evidence. Through case-studies, this framework will also highlight potential knowledge gaps. The proposed activity is therefore devoted to delineating the right path for scaling and
prioritizing mycotoxins in terms of risk-ranking and consequent mitigation opportunities.info:eu-repo/semantics/publishedVersio
Measurement of inositol 1,4,5-trisphosphate in living cells using an improved set of resonance energy transfer-based biosensors
Improved versions of inositol-1,4,5-trisphosphate (InsP3) sensors were created to follow intracellular InsP3 changes in single living cells and in cell populations. Similar to previous InsP3 sensors the new sensors are based on the ligand binding domain of the human type-I InsP3 receptor (InsP3R-LBD), but contain a mutation of either R265K or R269K to lower their InsP3 binding affinity. Tagging the InsP3R-LBD with N-terminal Cerulean and C-terminal Venus allowed measurement of Ins P3 in single-cell FRET experiments. Replacing Cerulean with a Luciferase enzyme allowed experiments in multi-cell format by measuring the change in the BRET signal upon stimulation. These sensors faithfully followed the agonist-induced increase in InsP3 concentration in HEK 293T cells expressing the Gq-coupled AT1 angiotensin receptor detecting a response to agonist concentration as low as 10 pmol/L. Compared to the wild type InsP3 sensor, the mutant sensors showed an improved off-rate, enabling a more rapid and complete return of the signal to the resting value of InsP3 after termination of M3 muscarinic receptor stimulation by atropine. For parallel measurements of intracellular InsP3 and Ca2+ levels in BRET experiments, the Cameleon D3 Ca2+ sensor was modified by replacing its CFP with luciferase. In these experiments depletion of plasma membrane PtdIns(4,5)P2 resulted in the fall of InsP3 level, followed by the decrease of the Ca2+-signal evoked by the stimulation of the AT1 receptor. In contrast, when type-III PI 4-kinases were inhibited with a high concentration of wortmannin or a more specific inhibitor, A1, the decrease of the Ca2+-signal preceded the fall of InsP3 level indicating an InsP3-, independent, direct regulation of capacitative Ca2+ influx by plasma membrane inositol lipids. Taken together, our results indicate that the improved InsP3 sensor can be used to monitor both the increase and decrease of InsP3 levels in live cells suitable for high-throughput BRET applications. © 2015, Public Library of Science. All rights reserved
The influence of menstrual risk factors on tumor characteristics and survival in postmenopausal breast cancer
20-Year Risks of Breast-Cancer Recurrence after Stopping Endocrine Therapy at 5 Years
The administration of endocrine therapy for 5 years substantially reduces recurrence rates during and after treatment in women with early-stage, estrogen-receptor (ER)-positive breast cancer. Extending such therapy beyond 5 years offers further protection but has additional side effects. Obtaining data on the absolute risk of subsequent distant recurrence if therapy stops at 5 years could help determine whether to extend treatment
Seasonal variations of the digestive tract of the Eurasian beaver castor fiber.
Forage availability for wild rodents varies with season. In turn, the composition of food can affect morphometric parameters of the digestive tract. This study was performed in Eurasian beavers (Castor fiber) whose population was close to extinction in most Eurasian countries, but has now increased. Due to the previous low number of studies, information about the effect of forage availability on the digestive tract morphology has previously been lacking. This study was performed using beavers captured from the natural environment during three seasons of different forage availability: winter, summer and autumn. It was found that the diet of the beaver varied during the year; in winter it was dominated by woody material consisting of willow shoots, whereas in summer the diet was primarily herbs, grass and leaves. Season also affected the mass of digested contents of the digestive tract. The digestive content increased in the caecum and colon in winter and autumn, when poor-quality food dominated the beaver's diet. The results indicated that the digestive tract parameters of beavers varied based on the composition of available forage
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