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As part of a clinical validation of a new brain-dedicated PET system (CMB), image quality of this scanner has been compared to that of a whole-body PET/CT scanner. To that goal, Hoffman phantom and patient data were obtined with both devices. Since CMB does not use a CT for attenuation correction (AC) which is crucial for PET images quality, this study includes the evaluation of CMB PET images using emission-based or CT-based attenuation maps. PET images were compared using 34 image quality metrics. Moreover, a neural network was used to evaluate the degree of agreement between both devices on the patients diagnosis prediction. Overall, results showed that CMB images have higher contrast and recovery coefficient but higher noise than PET/CT images. Although SUVr values presented statistically significant differences in many brain regions, relative differences were low. An asymmetry between left and right hemispheres, however, was identified. Even so, the variations between the two devices were minor. Finally, there is a greater similarity between PET/CT and CMB CT-based AC PET images than between PET/CT and the CMB emission-based AC PET images. [ABSTRACT FROM AUTHOR]

The power of social media in spreading the idea of wellbeing has already been addressed by several psychologists and scholars through the analysis of the vocabulary; however, the use of the human flourishing (HF) concept in such platforms has not yet been analyzed. This study addresses such a topic by analyzing more than 600 thousand Twitter messages posted by a community of users who associate themselves with HF and comparing them to more than 400 thousand messages in other Twitter lists. The study aims to identify the HF users' interests, the richness in their vocabulary, the feelings and emotions that they share, and the grammar used in their constructions. Such an analysis was conducted through text mining computational methods, including sentiment analysis, natural language processing (NLP), and topic modeling. The results revealed that although HF users employ average vocabulary diversity, they share more positive emotions, and a greater variety of emojis. They also tended to discuss different topics, from more spiritual and health-related subjects to more practical matters related to work and success. Finally, they generally wrote from an empathetic state of mind, caring about people's day-to-day feelings and about the world. [ABSTRACT FROM AUTHOR]

Maternal metabolic status influences pregnancy and, consequently, the perinatal outcome. Resistin is a pro-inflammatory adipokine predominantly expressed and secreted by mononuclear cells, adipose tissue, and placental trophoblastic cells during pregnancy. Recently, we reported an inverse association between maternal resistin levels and fetal low-density lipoprotein cholesterol (LDL-C). Then, in this work, we used a human placental explant model and the trophoblast cell line JEG-3 to evaluate whether resistin affects placental LDL-C uptake. Resistin exposure induced the transcription factor SREBP-2, LDLR, and PCSK9 mRNA expression, and changes at the protein level were confirmed by immunohistochemistry and Western blot. However, for LDLR, the changes were not consistent between mRNA and protein levels. Using a labeled LDL-cholesterol (BODIPY FL LDL), uptake assay demonstrated that the LDL-C was significantly decreased in placental explants exposed to a high dose of resistin and a lesser extent in JEG-3 cells. In summary, resistin induces PCSK9 expression in placental explants and JEG-3 cells, which could be related to negative regulation of the LDLR by lysosomal degradation. These findings suggest that resistin may significantly regulate the LDL-C uptake and transport from the maternal circulation to the fetus, affecting its growth and lipid profile. [ABSTRACT FROM AUTHOR]

Amphibians have some of the most variable genome sizes among vertebrates. Genome size variation has been attributed to repetitive and noncoding DNA, including satellite repeats, transposable elements, introns, and nuclear insertions of viral and organelle DNA. In vertebrates, satellite DNAs have been widely described in mammals, but few molecular studies have been carried out in amphibians. Here, we provide a detailed characterization of a new family of satellite DNA, present in all 15 examined species of the family Bufonidae. Southern-blot analysis and PCR reveal that this satellite is formed by monomers of 807 bp, is organized in tandem arrays, and has an AT-content of 57.4%. Phylogenetic analyses show that most clades exhibit species-specific variances, indicating that this satellite DNA has evolved by concerted evolution. The homogenization/fixation process is heterogeneous in Bufonidae, where the genera Bufo and Bufotes do not show species-specific differences, while populations from Rhinella marina exhibit population-specific changes. Additionally, variants of this satellite DNA have been identified in Duttaphrynus melanostictus and R. marina, supporting the 'library hypothesis' (a set, 'library', of satellite DNAs is shared by a species group). Physical mapping in Bufo bufo, Bufo spinosus, Epidalea calamita and Bufotes viridis provides evidence that this repetitive DNA is not dispersed in the karyotype, but accumulated in pericentromeric regions of some chromosomal pairs. This location, together with its presence in the transcriptomes of bufonids, could indicate a role in centromere function or heterochromatin formation and maintenance. [ABSTRACT FROM AUTHOR]

Introduction: Available intracystic biomarkers show a limited accuracy for characterizing cystic pancreatic lesions (CPL). Glucose is an attractive alternative due to its availability, low cost and the possibility of on-site quantification by glucometry. Aim: To evaluate the diagnostic accuracy of on-site glucometry from samples obtained by EUS-FNA in the differential diagnosis between mucinous from non-mucinous CPL. Methods: Retrospective, multicentre, cross-sectional study of patients who underwent EUS-FNA of a CPL. A derivation and a validation cohorts were evaluated. Intracystic glucose was quantified by on-site glucometry and colorimetry in the lab. Final diagnosis was based on surgical specimens or global evaluation of clinical and imaging data, cytology and intracystic CEA. Diagnostic accuracy was based on Receiver Operating Curve (ROC) curve analysis. Intraclass correlation coefficient (ICC) between on-site and lab glucose levels was calculated. Results: Seventy two patients were finally analysed (40 in the derivation cohort and 32 in the validation cohort). Intracystic glucose levels by on-site glucometry was 12.3 ± 28.2 mg/dl for mucinous CPL and 103.3 ± 58.2 mg/dl for non-mucinous CPL, p < 0.001. For an optimal cut-off point of 73 mg/dl, on-site glucose had a sensitivity, specificity, and positive and negative predictive value for the diagnosis of mucinous CPL of 0.89, 0.90, 0.94, 0.82 respectively in the derivation cohort, and 1.0, 0.71, 0.91, 1.0 respectively in the validation cohort. Correlation of on-site and lab glucose quantification was very high (ICC = 0.98). Conclusion: On-site glucometry is a feasible, accurate and reproducible method for the characterization of CPL after EUS-FNA. It shows an excellent correlation with laboratory glucose values. Registration number: 2019/612. [ABSTRACT FROM AUTHOR]

A two-dimensional material – Mg2B4C2, belonging to the family of the conventional superconductor MgB2, is theoretically predicted to exhibit superconductivity with critical temperature Tc estimated in the 47–48 K range (predicted using the McMillian-Allen-Dynes formula) without any tuning of external parameters such as doping, strain, or substrate-induced effects. The origin of such a high intrinsic Tc is ascribed to the presence of strong electron-phonon coupling and large density of states at the Fermi level. This system is obtained after replacing the chemically active boron-boron surface layers in a MgB2 slab by chemically inactive boron-carbon layers. Hence, the surfaces of this material are inert. Our calculations confirm the stability of 2D Mg2B4C2. We also find that the key features of this material remain essentially unchanged when its thickness is increased by modestly increasing the number of inner MgB2 layers. [ABSTRACT FROM AUTHOR]

The applicability extent of hadron therapy for tumor treatment is currently limited by the lack of reliable online monitoring techniques. An active topic of investigation is the research of monitoring systems based on the detection of secondary radiation produced during treatment. MACACO, a multi-layer Compton camera based on LaBr3 scintillator crystals and SiPMs, is being developed at IFIC-Valencia for this purpose. This work reports the results obtained from measurements of a 150 MeV proton beam impinging on a PMMA target. A neural network trained on Monte Carlo simulations is used for event selection, increasing the signal to background ratio before image reconstruction. Images of the measured prompt gamma distributions are reconstructed by means of a spectral reconstruction code, through which the 4.439 MeV spectral line is resolved. Images of the emission distribution at this energy are reconstructed, allowing calculation of the distal fall-off and identification of target displacements of 3 mm. [ABSTRACT FROM AUTHOR]

The Iberian Algyroides (Algyroides marchi) is a lacertid lizard with one of the narrowest distribution ranges in continental Europe, restricted to a minute area in the Subbaetic mountains in SE Spain. Due to specific habitat requirements, this species is considered threatened by climate change and habitat degradation. Here, an improved and time-calibrated multilocus phylogenetic analysis, combining two mitochondrial, three nuclear markers as well as a battery of 12 microsatellite loci, was performed. Moreover, ancestral changes in effective population size were determined under Approximate Bayesian Computation (ABC) analysis. In parallel, past, present and future habitat suitability was inferred using Ecological Niche Models (ENMs). The diversification of A. marchi in the Iberian Peninsula began during the Upper-Pleistocene around 0.10 Mya. However, during the Last Interglacial the species had much larger suitable habitats along NE Iberia and/or the Cantabrian region. Indeed, ABC analysis indicates that not the Last Interglacial, but instead the Last Glacial Maximum led to a population bottleneck followed by a recovery/expansion. The footprint of this complex evolutionary history is reflected today in six monophyletic lineages, with little genetic differentiation and geographic coherency. This pattern most likely arises from the climatic oscillations during the Pleistocene, leading to a complete range shift and secondary contact, with very divergent haplogroups in sympatry and exchanging genes. Finally, the ENMs predict a considerable future retraction and shift in the area suitable for the species, which should be taken into account for conservation policies. [ABSTRACT FROM AUTHOR]

Gauge theories with general covariance are particularly reluctant to quantization. We discuss the example of the Hamiltonian formulation of the relativistic point particle that, despite its apparent simplicity, is of crucial importance since a number of point particle systems can be cast into this form on a higher dimensional Rindler background, as recently pointed out by Hojman. It is shown that this system can be equipped with a hidden local, symmetry generating, constraint which on the one hand does not bother the classical evolution and on the other hand simplifies the realization of the path integral quantization. Even though the positive impact of the hidden symmetry is more evident in the Lagrangian version of the theory, it is still present through the suggested Hamiltonian constraint. [ABSTRACT FROM AUTHOR]

Agriculture practices have been widely proposed as the major cause of amphibian population decline. However, the majority of these results have been based on laboratory experiments. The present study was conducted to test the repercussion of wetland sediment provenance on amphibian larval development. Bufo bufo larvae were used in two different treatments in an outdoor experiment, the first one using sediment from one wetland surrounded by intensive agricultural practices, and the second using sediment with no record of agrochemical uses. A negative effect was observed in the agricultural treatment, from subcellular to individual level. The results showed that the sediment from agricultural practices watershed generates a reduction in survival. Furthermore, individuals that developed under this treatment showed a lower total length and a delay in the time necessary to complete metamorphosis; these features are connected with recruitment success. In the same way, biochemical analysis showed high values of lipid peroxidation in metamorphs developing in sediments from an agricultural area. Finally, the results obtained highlight the importance of considering the sediments, not only the water, as origin treatment, allowing us to understand the consequences on amphibian populations that inhabit areas affected by intensive agriculture. [ABSTRACT FROM AUTHOR]

Polycystic ovary syndrome (PCOS) affects 6-10% of women and could be considered one of the most common endocrine alterations in women of reproductive age. The syndrome is characterized by several hormonal and metabolic alterations, including insulin resistance and hyperandrogenism, which play a severe detrimental role in the patient's fertility. We aimed to offer an overview about drug metabolism in the PCOS population. Nevertheless, we did not find any study that directly compared drug metabolism between PCOS and healthy women. We therefore decided to summarize briefly how hormonal and insulin sensitizer drugs act differently in healthy and PCOS women, who show altered steroidogenesis by theca cells and metabolic imbalance, focusing especially on assisted reproductive techniques. To date, data about drug metabolism in the PCOS population appears to be extremely limited. This important gap could have significant implications for therapeutic approaches and future perspectives: the dosage of drugs commonly used for the treatment of PCOS women should be tailored according to each patient's characteristics; we should implement new clinical trials in order to identify the best pharmacologic strategy for PCOS patients undergoing in vitro fertilization (IVF); it would be advisable to create an international expert panel to investigate the drug metabolism in the PCOS population. [ABSTRACT FROM AUTHOR]

The k-nearest neighbors method (kNN) is a nonparametric, instance-based method used for regression and classification. To classify a new instance, the kNN method computes its k nearest neighbors and generates a class value from them. Usually, this method requires that the information available in the datasets be precise and accurate, except for the existence of missing values. However, data imperfection is inevitable when dealing with real-world scenarios. In this paper, we present the kNNimp classifier, a k-nearest neighbors method to perform classification from datasets with imperfect value. The importance of each neighbor in the output decision is based on relative distance and its degree of imperfection. Furthermore, by using external parameters, the classifier enables us to define the maximum allowed imperfection, and to decide if the final output could be derived solely from the greatest weight class (the best class) or from the best class and a weighted combination of the closest classes to the best one. To test the proposed method, we performed several experiments with both synthetic and real-world datasets with imperfect data. The results, validated through statistical tests, show that the kNNimp classifier is robust when working with imperfect data and maintains a good performance when compared with other methods in the literature, applied to datasets with or without imperfection. [ABSTRACT FROM AUTHOR]

The watershed land uses in Mediterranean wetlands are essential to understand the functioning of aquatic communities. This study was designed to assess the relationship between watershed land uses, wetland characteristics and zooplankton assemblages (branchiopods and copepods) in 24 Mediterranean wetlands of the southern Iberian Peninsula, which greatly differ in both wetland land uses (olive groves, pasture, scrublands, and forest) and in their morphometric and limnological features. Firstly, results from a Principal Component Analysis allowed us to classify wetlands in two categories: impacted and non-impacted. Then, one-way Analysis of Variance was performed to test differences in zooplankton species richness and a Permutational Analysis of Variance was performed to test differences in zooplankton assemblages between categories. Lastly, a Non-metric Multidimensional Scaling analysis was chosen for the lake-by-species ordination. The results support the hypothesis that zooplankton richness and composition were negatively affected by watershed land uses, mainly agriculture practices. Moreover, species zooplankton assemblages were clearly linked to the two different wetlands categories. The present study puts forward the important role of zooplankton community for testing land use effects in Mediterranean wetlands. [ABSTRACT FROM AUTHOR]

We study the issue of computational efficiency for Gauss-Newton ( GN) non-linear least-squares optimization in the context of image alignment. We introduce the Constant Jacobian Gauss-Newton ( CJGN) optimization, a GN scheme with constant Jacobian and Hessian matrices, and the equivalence and independence conditions as the necessary requirements that any function of residuals must satisfy to be optimized with this efficient approach. We prove that the Inverse Compositional ( IC) image alignment algorithm is an instance of a CJGN scheme and formally derive the compositional and extended brightness constancy assumptions as the necessary requirements that must be satisfied by any image alignment problem so it can be solved with an efficient compositional scheme. Moreover, in contradiction with previous results, we also prove that the forward and inverse compositional algorithms are not equivalent. They are equivalent, however, when the extended brightness constancy assumption is satisfied. To analyze the impact of the satisfaction of these requirements we introduce a new image alignment evaluation framework and the concepts of short- and wide-baseline Jacobian. In wide-baseline Jacobian problems the optimization will diverge if the requirements are not satisfied. However, with a good initialization, a short-baseline Jacobian problem may converge even if the requirements are not satisfied. [ABSTRACT FROM AUTHOR]

Performance improvement tests of MACACO: a Compton telescope based on continuous crystals and SiPMs. Performance improvement tests of MACACO: A Compton telescope based on continuous crystals and SiPMs. [Extracted from the article]

In this paper we present a stepwise construction of the path integral over relativistic orbits in Euclidean spacetime. It is shown that the apparent problems of this path integral, like the breakdown of the naive Chapman-Kolmogorov relation, can be solved by a careful analysis of the overcounting associated with local and global symmetries. Based on this, the direct calculation of the quantum propagator of the relativistic point particle in the path integral formulation results from a simple and purely geometric construction. [ABSTRACT FROM AUTHOR]