Groupwise image (GW) registration is customarily used for subsequent processing in medical imaging. However, it is computationally expensive due to repeated calculation of transformations and ...gradients. In this paper, we propose a deep learning (DL) architecture that achieves GW elastic registration of a 2D dynamic sequence on an affordable average GPU. Our solution, referred to as dGW, is a simplified version of the well-known U-net. In our GW solution, the image that the other images are registered to, referred to in the paper as template image, is iteratively obtained together with the registered images. Design and evaluation have been carried out using 2D cine cardiac MR slices from 2 databases respectively consisting of 89 and 41 subjects. The first database was used for training and validation with 66.6–33.3% split. The second one was used for validation (50%) and testing (50%). Additional network hyperparameters, which are—in essence—those that control the transformation smoothness degree, are obtained by means of a forward selection procedure. Our results show a 9-fold runtime reduction with respect to an optimization-based implementation; in addition, making use of the well-known structural similarity (SSIM) index we have obtained significative differences with dGW with respect to an alternative DL solution based on Voxelmorph.
The transversal screw was introduced in order to overcome some disadvantages of the transocclusal screw. However, its mechanical risk has not been studied sufficiently. The main purpose of this ...research was to assess and compare stress distribution in the screws and abutment of a single‐crown implant with transversal and transocclusal screw models. Two 3D models were assembled to analyse a single‐implant–supported prosthesis with transversal and transocclusal screws embedded in the jawbone. The crown was subjected to a static load of value 300 N with different levels of inclination. The transversal screw model, with an axial load of 15°, was the one with lowest stress values in all its components. However, the stress was greater with more inclined loads when compared with the transocclusal model. The prosthetic transversal screw showed much less stress than the rest of the components for any load inclination. The transversal screw design is the option with the lowest risk of mechanical complications, both in the prosthetic screw and in the abutment screw, when applying forces of lower inclination. The more oblique forces favoured a better biomechanical environment in the abutment and its screw in the transocclusal screw model.
In this paper, it was found that, compared with the transocclusal screw model, the transversal screw model may be the choice with the lowest risk of possible mechanical complications in the prosthetic screw and in the abutment and abutment screw when loads of low inclination are applied. The behaviour of the stress levels for any of the prosthetic components is similar for both models, and these increase as the load inclination becomes greater.
The genus Pestivirus, family Flaviviridae, includes four economically important viruses of livestock, i.e., bovine viral diarrhea virus-1 (BVDV-1) and -2 (BVDV-2), border disease virus (BDV) and ...classical swine fever virus (CSFV). Erns and Npro, both expressed uniquely by pestiviruses, counteract the host’s innate immune defense by interfering with the induction of interferon (IFN) synthesis. The structural envelope protein Erns also exists in a soluble form and, by its endoribonuclease activity, degrades immunostimulatory RNA prior to their activation of pattern recognition receptors. Here, we show that at least three out of four positively-charged residues in the C-terminal glycosaminoglycan (GAG)-binding site of BVDV-Erns are required for efficient cell entry, and that a positively charged region more upstream is not involved in cell entry but rather in RNA-binding. Moreover, the C-terminal domain on its own determines intracellular targeting, as GFP fused to the C-terminal amino acids of Erns was found at the same compartments as wt Erns. In summary, RNase activity and uptake into cells are both required for Erns to act as an IFN antagonist, and the C-terminal amphipathic helix containing the GAG-binding site determines the efficiency of cell entry and its intracellular localization.
The IBA myQA® SRS high-resolution solid-state detector was evaluated in the context of robotic radiosurgery delivered using CyberKnife®. The performance was investigated for periodic machine delivery ...quality assurance (DQA) and patient-specific treatment verification. myQA® SRS is a 140 × 120 mm CMOS matrix with 400 µm resolution, allocated in a cylindrical ABS phantom topped by a hemispheric cap. Evaluations included: periodic DQA tests, angular response, dose-rate dependence and Iris variable aperture collimator field size measurements. For patient-specific QA various intracranial targets were studied (Gamma Index, 3%/1 mm agreement criteria), taking into account also the detector’s angular response. Results for periodic DQA were in accordance with the machine commissioning data. Dose-rate dependence was confirmed, and angular response tests resulted in a signal decay >5% when beams were delivered outside a ±50° amplitude cone with respect to the vertical direction. Concerning patient-specific QA, >50° angled beams elimination led to a Gamma Index passing rates improvement ranging between +3% and +115%. IBA myQA® SRS proved to be a suitable device for many CyberKnife® constancy DQA checks, providing high-resolution real-time results. Patient-specific Gamma tests showed high passing rates once angular dependence corrections were performed, even in high complexity treatments such as those for trigeminal neuralgia targets.
Introduction: The formation of bacterial biofilms on knee arthroplasty implants can have catastrophic consequences. The aim of this study was to analyze the effectiveness of the bioelectric effect in ...the elimination of bacterial biofilms on cultivated knee arthroplasty implants. Methods: A novel device was designed to deliver a bioelectric effect on the surface of knee arthroplasty implants. 4-femoral prosthetic implants were cultivated with a staphylococcus aureus inoculum for 15 days. The components were divided into four different groups: A (not treated), B (normal saline 20-minutes), C (bioelectric effect 10-minutes), D (bioelectric effect 20-minutes). The implants were sonicated, and the detached colonies were quantified as the number of colony-forming unit (CFUs). The implants were sterilised and the process was repeated in a standardized manner four more times, to obtain a total of five samples per group. Results: The number of the CFUs after a 10-minute exposure to the bioelectric effect was of 208.2 ± 240.4, compared with 6,041.6 ± 2010.7 CFUs in group A, representing a decrease of 96.5% ± 4.3 ( p = 0.004). And a diminution of 91.8% ± 7.9 compared with 2,051.0 ± 1,364.0 CFUs in group B ( p = 0.109). The number of bacterial colonies after a 20-minute exposure to the bioelectric effect was 70 ± 126.7 CFUs, representing a decrease of 98.9% ± 1.9 ( p = 0.000) compared with group A. And a decrease of 97.8% ± 3.0 ( p = 0.019) compared with group B. Conclusions: The bioelectric effect was effective in the elimination of bacterial biofilm from knee arthroplasty implants. This method could be used in the future as part of conventional surgical procedures.
The risk of developing drug addiction is strongly influenced by the epigenetic landscape and chromatin remodeling. While histone modifications such as methylation and acetylation have been studied in ...the ventral tegmental area and nucleus accumbens (NAc), the role of H2A monoubiquitination remains unknown. Our investigations, initially focused on the scaffold protein melanoma-associated antigen D1 (Maged1), reveal that H2A monoubiquitination in the paraventricular thalamus (PVT) significantly contributes to cocaine-adaptive behaviors and transcriptional repression induced by cocaine. Chronic cocaine use increases H2A monoubiquitination, regulated by Maged1 and its partner USP7. Accordingly, Maged1 specific inactivation in thalamic Vglut2 neurons, or USP7 inhibition, blocks cocaine-evoked H2A monoubiquitination and cocaine locomotor sensitization. Additionally, genetic variations in MAGED1 and USP7 are linked to altered susceptibility to cocaine addiction and cocaine-associated symptoms in humans. These findings unveil an epigenetic modification in a non-canonical reward pathway of the brain and a potent marker of epigenetic risk factors for drug addiction in humans.
Language MOOCs Martin-Monje, Elena; Barcena, Elena
2014, 2015, 2015-01-29, 2015-08-17
eBook, Book
Odprti dostop
Language MOOCs (or LMOOCs) are dedicated Web-based online courses for second languages with unrestricted access and potentially unlimited participation. They are generating interest and expectation ...in the contexts of university education, lifelong learning and online training in general. This pioneering book presents an initial analysis of the theoretical and methodological issues underlying LMOOCs and presents empirical evidence of their potential for the development of language communicative competences, based upon previously unpublished research. It provides a mosaic-like view of LMOOC research, not only with respect to the geographical and institutional origin of its authors, but also to the heterogeneous nature of their respective academic backgrounds, and suggests directions for future development. As in other types of online language courses, the integration of the results of multidisciplinary research projects and teaching experiences related to LMOOCs is fundamental to make the field advance steadily and respond to some of the real challenges and problems faced by individuals working and living in competitive plurilingual societies today. (DIPF/Orig.).
Measures of premature mortality have been used to guide debates on future health priorities and to monitor the population health status. Standard expected years of life lost (SEYLL) is one of the ...methods used to assess the time lost due to premature death. This article affords an overview of premature mortality in Spain for the year 2008.
A population-based study was conducted estimating SEYLL by sex and age groups. SEYLL, a key component of the disability-adjusted life years measure of disease burden, was calculated using Princeton West standard life tables with life expectancy at birth fixed at 80 years for males and 82.5 years for females. Population data and specific death records were obtained from the official registers of the National Institute of Statistics. All data were analysed and prepared in GesMor and Epidat software packages.
The burden of premature mortality was estimated at 2.1 million SEYLL when age at death is taken into account. Males lost 60.9% and females lost 39.1% of total SEYLL. Malignant tumors (34.5%) and cardiovascular diseases (24.0%) were the leading categories in terms of SEYLL. Ischaemic heart disease (8.5%) and lung cancers (8.0%) were the most common specific causes of SEYLL followed by cerebrovascular diseases (5.9%), colorectal cancer (4.1%), road traffic accidents (3.5%), Alzheimer and other dementias (2.9%), chronic obstructive pulmonary disease (2.8%), breast cancer (2.8%) and suicides (2.6%).
In Spain, premature mortality was essentially due to chronic non-communicable diseases. Data provided in this study are relevant for a more balanced health agenda aimed at reducing the burden of premature mortality. This study also represents a first step in estimating the overall burden of disease in terms of premature death and disability.
Background
Surgery represents the first-choice treatment for spinal intradural tumours. On the other hand, whether it is most appropriate in the setting of recurrences, residual or multiple lesions ...remains an open question. Moreover, some patients are less than ideal candidates for surgery. In this study we report about our own radiosurgery experience in the treatment of benign intradural extramedullary tumours of the spine.
Methods
In our study we analyzed the outcomes for 18 patients (21 lesions) treated for benign intradural extramedullary lesions, with a minimum follow-up period of 32 months. The lesions included 11 meningiomas, 9 schwannomas and 1 neurofibroma.
Results
The mean follow-up was 43 months (32–73 months). The median tumour volume was 2 cc (0.2–17.7 cc). Eleven lesions underwent single-fraction treatment (mean prescribed dose ranging from 10 to 13 Gy). The others received a multisession radiosurgery treatment (4–6 fractions) with a mean prescription dose ranging from 18.5 to 25 Gy. The maximum dose to the spinal cord ranged from 9.2 to 26 Gy. During the follow-up period, none of the lesions showed radiological evidence of progression. Neurological status was preserved or improved and no permanent sequelae were observed. Significant and durable pain relief was observed.
Conclusions
Although surgical excision remains the primary treatment option for most intradural tumours, radiosurgery offers a real alternative therapeutic modality, especially in case of recurrent and residual lesions or when surgery is contraindicated.
PDF
