Accurate brain tissue segmentation in magnetic resonance imaging (MRI) has attracted the attention of medical doctors and researchers since variations in tissue volume and shape permit diagnosing and ...monitoring neurological diseases. Several proposals have been designed throughout the years comprising conventional machine learning strategies as well as convolutional neural networks (CNNs) approaches. In particular, in this paper, we analyze a sub-group of deep learning methods producing dense predictions. This branch, referred in the literature as fully CNN (FCNN), is of interest as these architectures can process an input volume in less time than CNNs. Our study focuses on understanding the architectural strengths and weaknesses of literature-like approaches. We implement eight FCNN architectures inspired by robust state-of-the-art methods on brain segmentation related tasks and use them within a standard pipeline. We evaluate them using the IBSR18, MICCAI2012, and iSeg2017 datasets as they contain infant and adult data and exhibit different voxel spacing, image quality, number of scans, and available imaging modalities. The discussion is driven in four directions: comparison between 2D and 3D approaches, the relevance of multiple imaging sequences, the effect of patch size, and the impact of patch overlap as a sampling strategy for training and testing models. Besides the aforementioned analysis, we show that the methods under evaluation can yield top performance on the three data collections. A public version is accessible to download from our research website to encourage other researchers to explore the evaluation framework.
This paper illustrates, for the first time, the use of an evolutionary strategy for the coordination of FACTS (flexible AC transmission systems). The main purpose of the current work involves the ...study of power systems with the use of FACTS controllers. FACTS controllers cannot only increase considerably power transmission capacity without having to invest on the production of new power lines—but they can also enhance stability in power systems. The task of searching and finding the optimal values of control variables for the FACTS controllers is a complex optimization problem which cannot be easily solved.
The results achieved in this work suggest the effective use of evolutionary strategies in order to obtain the optimal values of control variables for the FACTS located on a power system. The illustrative example and final conclusions allow considering evolutionary strategies as one of the best alternatives for the coordination of FACTS.
The present study aimed to investigate, for the first time, the presence of free amino acids in stingless bee (
Meliponinae
) honey samples from nine species, using high-performance liquid ...chromatography coupled to fluorescence (HPLC/FLD) and HPLC coupled to mass spectrometry (HPLC/MS-single quadrupole) detectors. Seventeen free amino acids were investigated, and 16 were determined. Phenylalanine (5.20–1231 mg kg
−1
) and proline (12.1–762 mg kg
−1
) were the majority free amino acids, which were found in all the samples; on the other hand, histidine was not identified in either of the samples. The results summarized in this study confirm not only the presence, but also the diversity of free amino acids in the analyzed stingless bee honey samples.
Coronary revascularization in patients with spontaneous coronary artery dissection (SCAD) is challenging. Indications and results of percutaneous coronary interventions (PCI) in SCAD patients are not ...well established.
To assess indications and results of PCI in SCAD.
The minimum basic data set of the Spanish National Health System (years 2016-2019) was used to identify 804 episodes of acute myocardial infarction (AMI) and SCAD, with a crude in-hospital mortality rate of 3%. Of these, 368 (46.8%) patients were revascularized with PCI during admission whereas 436 (54.2%) were managed conservatively.
Revascularization and in-hospital mortality rates both declined over the study period (p for trend both < 0.05). SCAD patients treated with PCI were older, more frequently male, and had higher frequency of diabetes, ST-segment elevation AMI and cardiogenic shock, compared to patients managed conservatively. The crude in-hospital mortality rate was higher in patients treated with PCI (4.9% vs. 1.4%;
= 0.004). However, after adjusting by propensity score (223 pairs) the in-hospital mortality rate was similar in the two groups (Adj OR: 1.21; 95%CI: 0.30-1.57;
= 0.76). Readmissions at 30-days were higher in patients managed conservatively (7.1 vs. 1.6%,
< 0.001) and this difference was maintained after propensity score adjustment (Adj average treatment effect: 2% vs. 12.2%; OR: 0.15; 95%CI: 0.04-0.45;
< 0.001).
Revascularization is frequently used in unselected patients with AMI and SCAD but its use is declining. Patients with SCAD treated with PCI have a higher in-hospital mortality but this appears to be explained by their adverse baseline clinical characteristics.
A significant proportion of cases of cardiogenic shock (CS) are due aetiologies other than acute coronary syndromes (non ACS-CS). We assessed differences regarding clinical profile, management, and ...prognosis according to the cause of CS among nonselected patients with CS from a large nationwide database.
We performed an observational study including patients admitted from the hospitals of the Spanish National Health System (SNHS) with a principal or secondary diagnosis code of CS (2016-2019). Data were obtained from the Minimum Basic Data Set (MBDS). Hospitals were classified according to the availability of cardiology related resources, as well as the availability of Intensive Cardiac Care Unit (ICCU).
A total of 10,826 episodes of CS were included, of whom 5,495 (50.8%) were non-ACS related. Non ACS-CS patients were younger (71.5 vs. 72.4 years) and had a lower burden of arteriosclerosis-related comorbidities. Non ACS-CS cases underwent less often invasive procedures and presented lower in-hospital mortality (57.1% vs. 61%,p < 0.001). The most common main diagnosis among non ACS-CS was acute decompensation of chronic heart failure (ADCHF) (35.4%). A lower risk-adjusted in-hospital mortality rate was observed in high volume hospitals (52.6% vs. 56.7%; p < 0.001), as well as in centers with ICCU (OR: 0.71; CI 95%: 0.58-0.87; p < 0.001).
More than a half of cases of CS were due to non-ACS causes. Non ACS-CS cases are a very heterogeneous group, with different clinical profile and management. Management at high-volume hospitals and availability of ICCU were associated with lower risk adjusted mortality among non ACS-CS patients.
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The optimisation of green hydrogen production systems is challenging. Moreover, an accurate simulation of the system is required for effective optimisation. This study presents a novel method for ...optimising utility-scale hybrid photovoltaic–wind systems for hydrogen production using accurate simulation models. The optimisation objective is to minimise the levelised cost of hydrogen (LCOH) using genetic algorithms. Different types of systems (such as islanded systems, grid-connected systems with or without the possibility of purchasing electricity from the grid, and grid-connected systems considering power curtailment), are evaluated and optimised. Each combination of components and control strategy is simulated during the system lifetime (20 yrs) in time steps of 5 min, considering the degradation of renewable generators during the system lifetime and different real-time pricing curves and renewable resource curves for each year of the system lifetime. Accurate models are used in the simulations, including electrolyser efficiency dependent on the input power and cold-start extra ageing. An application example located in Zaragoza (Spain) is shown, obtaining LCOH from 4.74 to 16.06 €/kg, depending on the type of project and electrolyser.
•Utility-scale PV-wind-hydrogen optimisation of components and control.•Minimisation of the levelised cost of hydrogen (LCOH).•Four different types of systems, isolated or grid-connected.•Advanced models including electrolyser variable efficiency.•Each year different electricity price and irradiation; components degradation.
Squamous cell carcinoma (SCC) or epidermoid cancer is a frequent and aggressive malignancy. However in apparent paradox it retains the squamous differentiation phenotype except for very dysplastic ...lesions. We have shown that cell cycle stress in normal epidermal keratinocytes triggers a squamous differentiation response involving irreversible mitosis block and polyploidisation. Here we show that cutaneous SCC cells conserve a partial squamous DNA damage-induced differentiation response that allows them to overcome the cell division block. The capacity to divide in spite of drug-induced mitotic stress and DNA damage made well-differentiated SCC cells more genomically instable and more malignant in vivo. Consistently, in a series of human biopsies, non-metastatic SCCs displayed a higher degree of chromosomal alterations and higher expression of the S phase regulator Cyclin E and the DNA damage signal γH2AX than the less aggressive, non-squamous, basal cell carcinomas. However, metastatic SCCs lost the γH2AX signal and Cyclin E, or accumulated cytoplasmic Cyclin E. Conversely, inhibition of endogenous Cyclin E in well-differentiated SCC cells interfered with the squamous phenotype. The results suggest a dual role of cell cycle stress-induced differentiation in squamous cancer: the resulting mitotic blocks would impose, when irreversible, a proliferative barrier, when reversible, a source of genomic instability, thus contributing to malignancy.
This paper presents a new method in data mining to analyze the composition of the electric demand among the different consumption and the behavior of each type of load. The proposed method uses a ...heuristic optimization algorithm (Tabu Search) for minimizing the error between the real demand and the calculated approximation to this demand. This search is adaptative because the algorithm changes the relative weight of each load as well as the profile of each load. The obtained results show the good operation of the proposed methodology. Also, it is possible to observe that this approach to the knowledge of the demand is better than the classic approach in which “a picture” of the consumption can be obtained, while this methodology obtains the evolution of this consumption in time; that is to say, it shows “a movie” of the behavior of the loads.
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