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Generating synthetic multispectral images for semantic segmentation in forestry applications
In this paper, we introduce a GAN-based solution for generating synthetic multispectral images from fully-annotated RGB images for data augmentation purposes in forestry robotics applications at ground-level. Fully-annotated multispectral datasets are difficult to obtain with sufficient training samples when compared to RGB-based datasets, since annotation in this case is often very time-consuming and expensive due to the need for expert knowledge. In this text, a study comparing different GAN-based image translation models designed for data augmentation is presented. Synthetic images generated by the proposed solution are shown to be realistic enough to yield performance ratings comparable to what is obtained using real images
Drawing Boundaries
In âOn Drawing Lines on a Mapâ (1995), I suggested that the different ways we have of drawing lines on maps open up a new perspective on ontology, resting on a distinction between two sorts of boundaries: fiat and bona fide. âFiatâ means, roughly: human-demarcation-induced. âBona fideâ means, again roughly: a boundary constituted by some real physical discontinuity. I presented a general typology of boundaries based on this opposition and showed how it generates a corresponding typology of the different sorts of objects which boundaries determine or demarcate. In this paper, I describe how the theory of fiat boundaries has evolved since 1995, how it has been applied in areas such as property law and political geography, and how it is being used in contemporary work in formal and applied ontology, especially within the framework of Basic Formal Ontology
Impact of concomitant aortic regurgitation on long-term outcome after surgical aortic valve replacement in patients with severe aortic stenosis
<p>Abstract</p> <p>Background</p> <p>Prognostic value of concomitant aprtic regurgitation (AR) in patients operated for severe aortic stenosis (AS) is not clarified. The aim of this study was to prospectively examine the impact of presence and severity of concomitant AR in patients operated for severe AS on long-term functional capacity, left ventricular (LV) function and mortality.</p> <p>Methods</p> <p>Study group consisted of 110 consecutive patients operated due to severe AS. The patients were divided into AS group (56 patients with AS without AR or with mild AR) and AS+AR group (54 patients with AS and moderate, severe or very severe AR). Follow-up included clinical examination, six minutes walk test (6MWT) and echocardiography 12 and 104 months after AVR.</p> <p>Results</p> <p>Patients in AS group had lower LV volume indices throughout the study than patients in AS+AR group. Patients in AS group did not have postoperative decrease in LV volume indices, whereas patients in AS+AR group experienced decrease in LV volume indices at 12 and 104 months. Unlike LV volume indices, LV mass index was significantly lower in both groups after 12 and 104 months as compared to preoperative values. Mean LVEF remained unchanged in both groups throughout the study. NYHA class was improved in both groups at 12 months, but at 104 months remained improved only in patients with AS. On the other hand, distance covered during 6MWT was longer at 104 months as compared to 12 months only in AS+AR group (p = 0,013), but patients in AS group walked longer at 12 months than patients in AS+AR group (p = 0,002). There were 30 deaths during study period, of which 13 (10 due to cardiovascular causes) in AS group and 17 (12 due to cardiovascular causes) in AS+AR group. Kaplan-Meier analysis showed that the survival probability was similar between the groups. Multivariate analysis identified diabetes mellitus (beta 1.78, p = 0.038) and LVEF < 45% (beta 1.92, p = 0.049) as the only independent predictor of long-term mortality.</p> <p>Conclusion</p> <p>Our data indicate that the preoperative presence and severity of concomitant AR has no influence on long-term postoperative outcome, LV function and functional capacity in patients undergoing AVR for severe AS.</p
Evaluation of dose-dependent treatment effects after mid-trial dose escalation in biomarker, clinical, and cognitive outcomes for gantenerumab or solanezumab in dominantly inherited Alzheimer's disease
Introduction: While the Dominantly Inherited Alzheimer Network Trials Unit (DIAN-TU) was ongoing, external data suggested higher doses were needed to achieve targeted effects; therefore, doses of gantenerumab were increased 5-fold, and solanezumab was increased 4-fold. We evaluated to what extent mid-trial dose increases produced a dose-dependent treatment effect. Methods: Using generalized linear mixed effects (LME) models, we estimated the annual low- and high-dose treatment effects in clinical, cognitive, and biomarker outcomes. Results: Both gantenerumab and solanezumab demonstrated dose-dependent treatment effects (significant for gantenerumab, non-significant for solanezumab) in their respective target amyloid biomarkers (Pittsburgh compound B positron emission tomography standardized uptake value ratio and cerebrospinal fluid amyloid beta 42), with gantenerumab demonstrating additional treatment effects in some downstream biomarkers. No dose-dependent treatment effects were observed in clinical or cognitive outcomes. Conclusions: Mid-trial dose escalation can be implemented as a remedy for an insufficient initial dose and can be more cost effective and less burdensome to participants than starting a new trial with higher doses, especially in rare diseases. Highlights: We evaluated the dose-dependent treatment effect of two different amyloid-specific immunotherapies. Dose-dependent treatment effects were observed in some biomarkers. No dose-dependent treatment effects were observed in clinical/cognitive outcomes, potentially due to the fact that the modified study may not have been powered to detect such treatment effects in symptomatic subjects at a mild stage of disease exposed to high (or maximal) doses of medication for prolonged durations
Singular values of the Dirac operator in dense QCD-like theories
We study the singular values of the Dirac operator in dense QCD-like theories
at zero temperature. The Dirac singular values are real and nonnegative at any
nonzero quark density. The scale of their spectrum is set by the diquark
condensate, in contrast to the complex Dirac eigenvalues whose scale is set by
the chiral condensate at low density and by the BCS gap at high density. We
identify three different low-energy effective theories with diquark sources
applicable at low, intermediate, and high density, together with their
overlapping domains of validity. We derive a number of exact formulas for the
Dirac singular values, including Banks-Casher-type relations for the diquark
condensate, Smilga-Stern-type relations for the slope of the singular value
density, and Leutwyler-Smilga-type sum rules for the inverse singular values.
We construct random matrix theories and determine the form of the microscopic
spectral correlation functions of the singular values for all nonzero quark
densities. We also derive a rigorous index theorem for non-Hermitian Dirac
operators. Our results can in principle be tested in lattice simulations.Comment: 3 references added, version published in JHE
Impacto da exposição acadĂ©mica no estado de saĂșde de estudantes universitĂĄrios
OBJECTIVE: To assess the impact of academic life on health status of university students. METHODS: Longitudinal study including 154 undergraduate students from the Universidade de Aveiro, Portugal, with at least two years of follow-up observations. Sociodemographic and behavioral characteristics were collected using questionnaires. Students' weight, height, blood pressure, serum glucose, serum lipids and serum homocysteine levels were measured. Regression analysis was performed using linear mixed-effect models, allowing for random effects at the participant level. RESULTS: A higher rate of dyslipidemia (44.0% vs. 28.6%), overweight (16.3% vs. 12.5%) and smoking (19.3% vs. 0.0%) was found among students exposed to the academic life when compared to freshmen. Physical inactivity was about 80%. Total cholesterol, high density lipoprotein-cholesterol (HDL-C), triglycerides, systolic blood pressure, and physical activity levels were significantly associated with gender (p<0.001). Academic exposure was associated with increased low density lipoprotein-cholesterol (LDL-C) levels (about 1.12 times), and marginally with total cholesterol levels (p=0.041). CONCLUSIONS: High education level does not seem to have a protective effect favoring a healthier lifestyle and being enrolled in health-related areas does not seem either to positively affect students' behaviors. Increased risk factors for non-transmissible diseases in university students raise concerns about their well-being. These results should support the implementation of health promotion and prevention programs at universities.OBJETIVO: Avaliar a inïŹuĂȘncia da vida acadĂ©mica na saĂșde de estudantes universitĂĄrios.
MĂTODOS: Estudo longitudinal envolvendo 154 estudantes de graduação da Universidade de Aveiro, Portugal, por pelo menos dois anos de
acompanhamento. CaracterĂsticas sociodemogrĂĄïŹ cas e comportamentais foram recordados, por meio de questionĂĄrios. Foram medidos peso, altura,pressĂŁo arterial, glicemia, perïŹl lipĂdico e os nĂveis sĂ©ricos de homocisteĂna
dos alunos. Foi realizada anĂĄlise de regressĂŁo com modelos lineares mistos
considerando as medidas repetidas de cada sujeito.
RESULTADOS: Estudantes expostos à vida académica, quando comparados àqueles de ingresso recente à universidade apresentaram proporção mais elevada de dislipidemia (44,0% versus 28,6%), sobrepeso (16,3% versus
12,5%) e tabagismo (19,3% versus 0,0%). No geral, foi observada alta proporção de sedentarismo (cerca de 80%). O colesterol total, lipoproteĂna de alta densidade, triglicĂ©rides, pressĂŁo arterial sistĂłlica e nĂveis de atividade fĂsica apresentaram associação signiïŹ cativa com o gĂ©nero (p < 0,001). A exposição acadĂ©mica apresentou-se associada com o aumento dos nĂveis das lipoproteĂnas de baixa densidade (cerca de 1,12 vezes), e marginalmente com os nĂveis de
colesterol total (p = 0,041).
CONCLUSĂES: Nem o alto nĂvel de instrução parece ter papel protetor na adoção de estilo de vida saudĂĄvel, tampouco o envolvimento com ĂĄreas de saĂșde muda o comportamento dos estudantes. Altas proporçÔes de fatores
de risco para doenças nĂŁo-transmissĂveis em jovens universitĂĄrios podem afetar seu bem-estar. Os resultados podem servir de apoio Ă s universidades no desenvolvimento de programas de prevenção e promoção da saĂșde
Wnt signaling in breast cancer: have we come full circle?
Since the original identification of Wnt1 as a mammary oncogene in mouse mammary tumor virus infected mice, questions have been asked about its relevance to human breast cancer. Wnt1 is now known to be one of a large family of Wnt genes encoding structurally similar secreted signaling proteins, several of which are functionally redundant. The principal intracellular signaling pathway activated by these proteins has been elucidated in recent years. Components of this pathway include proto-oncogene products, such as ÎČ-catenin, and tumor suppressor proteins such as APC. Although WNT1 itself has not been implicated in human breast neoplasms, it has been reported that other WNT genes are sometimes overexpressed in human breast cancer and there is growing evidence that downstream components of the Wnt signaling pathway are activated in a significant proportion of breast tumors
Search for high-mass resonances decaying to dilepton final states in pp collisions at sâ=7 TeV with the ATLAS detector
The ATLAS detector at the Large Hadron Collider is used to search for high-mass resonances decaying to an electron-positron pair or a muon-antimuon pair. The search is sensitive to heavy neutral ZâČ gauge bosons, Randall-Sundrum gravitons, Z * bosons, techni-mesons, Kaluza-Klein Z/Îł bosons, and bosons predicted by Torsion models. Results are presented based on an analysis of pp collisions at a center-of-mass energy of 7 TeV corresponding to an integrated luminosity of 4.9 fbâ1 in the e + e â channel and 5.0 fbâ1 in the ÎŒ + ÎŒ âchannel. A Z âČ boson with Standard Model-like couplings is excluded at 95 % confidence level for masses below 2.22 TeV. A Randall-Sundrum graviton with coupling k/MPl=0.1 is excluded at 95 % confidence level for masses below 2.16 TeV. Limits on the other models are also presented, including Technicolor and Minimal ZâČ Models
Observation of associated near-side and away-side long-range correlations in âsNN=5.02ââTeV proton-lead collisions with the ATLAS detector
Two-particle correlations in relative azimuthal angle (ÎÏ) and pseudorapidity (Îη) are measured in âsNN=5.02ââTeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1ââÎŒb-1 of data as a function of transverse momentum (pT) and the transverse energy (ÎŁETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Îη|<5) ânear-sideâ (ÎÏâŒ0) correlation that grows rapidly with increasing ÎŁETPb. A long-range âaway-sideâ (ÎÏâŒÏ) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ÎŁETPb, is found to match the near-side correlation in magnitude, shape (in Îη and ÎÏ) and ÎŁETPb dependence. The resultant ÎÏ correlation is approximately symmetric about Ï/2, and is consistent with a dominant cosâĄ2ÎÏ modulation for all ÎŁETPb ranges and particle pT
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