Art through the colors of graffiti: from the perspective of the chromatic structure

Graffiti is a general term that describes inscriptions on a wall, a practice with ancient origins, ranging from simple drawings and writings to elaborate pictorial representations. Nowadays, the term graffiti commonly describes the street art dedicated to wall paintings, which raises complex questions, including sociological, legal, political and aesthetic issues. Here we examine the aesthetics of graffiti colors by quantitatively characterizing and comparing their chromatic structure to that of traditional paintings in museums and natural scenes obtained by hyperspectral imaging. Two hundred twenty-eight photos of graffiti were taken in the city of São Paulo, Brazil. The colors of graffiti were represented in a color space and characterized by several statistical parameters. We found that graffiti have chromatic structures similar to those of traditional paintings, namely their preferred colors, distribution, and balance. In particular, they have color gamuts with the same degree of elongation, revealing a tendency for combining similar colors in the same proportions. Like more traditional artists, the preferred colors are close to the yellow–blue axis of color space, suggesting that graffiti artists’ color choices also mimic those of the natural world. Even so, graffiti tend to have larger color gamuts due to the availability of a new generation of synthetic pigments, resulting in a greater freedom in color choice. A complementary analysis of graffiti from other countries supports the global generalization of these findings. By sharing their color structures with those of paintings, graffiti contribute to bringing art to the cities.This work was supported by Fundação CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) to Carlo M. Gaddi (88882.376512/2019-01), and the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2019

Acute Effects of L-Arginine Supplementation on Oxygen Consumption Kinetics and Muscle Oxyhemoglobin and Deoxyhemoglobin during Treadmill Running in Male Adults

International Journal of Exercise Science 12(2): 444-455, 2019. L-arginine is used as a nitric oxide related supplement intended to improve sports performance, and to enhance muscular recovery during exercise. However, the literature is inconclusive. The aim of this study was to determine the effects of acute oral L-arginine supplementation on O2 consumption kinetics and local muscle blood volume and oxygenation during treadmill running at two different intensities. Using a double-blind, crossover and placebo-controlled design, 11 young healthy male adults were randomly assigned to 6 g of L-arginine (ARG) or placebo (PLA) supplementation that was ingested 60 min before the exercise test. Tests consisted of treadmill run at two different intensities (5 min each; moderate, 90% of ventilatory threshold, VT; and heavy, 50% of the difference between VT and VO2peak) interspersed by 1-min walking. Respiratory gas exchange variables were measured continuously with an automated metabolic cart. Near infrared spectroscopy (NIRS) was used to continuously monitor muscle oxyhemoglobin and deoxyhemoglobin and total hemoglobin. Blood samples were collected before supplementation and 6 min after exercise. Two-way repeated measures ANOVA did not show differences in plasma nitrite concentrations between ARG or PLA conditions during the running tests. No significant differences were observed between ARG and PLA conditions for O2 kinetics as well as for NIRS variables. ARG supplementation does not improve physiological responses associated with oxygen cost and NIRS variables during running treadmill tests. Hence, our results do not support the use of L-arginine as an ergogenic aid for running performance in young healthy males

Diagnosis of Human Leptospirosis in a Clinical Setting: Real-Time PCR High Resolution Melting Analysis for Detection of Leptospira at the Onset of Disease:

Currently, direct detection of Leptospira can be done in clinical laboratories by conventional and by real-time PCR (qRT-PCR). We tested a biobank of paired samples of serum and urine from the same patient (202 patients) presenting at the hospital in an area endemic for leptospirosis using qRT-PCR followed by high resolution melting (HRM) analysis. The results were compared with those obtained by conventional nested PCR and with the serologic gold standard microscopic agglutination test (MAT). Differences were resolved by sequencing. qRT-PCR-HRM was positive for 46 of the 202 patients (22.7%, accuracy 100%) which is consistent with known prevalence of leptospirosis in the Azores. MAT results were positive for 3 of the 46 patients (6.5%). Analysis of paired samples allowed us to identify the illness point at which patients presented at the hospital: onset, dissemination or excretion. The melting curve analysis of Leptospira species revealed that 60.9% (28/46) of patients were infected with L. interrogans and 39.1% (18/46) were infected with L. borgpetersenii, both endemic to the Azores. We validated the use of qRT-PCR-HRM for diagnosis of leptospirosis and for identification of the Leptospira species at the earliest onset of infection in a clinical setting, in less than 2 hours.publishersversionpublishe

Evaluation of the influence of kyphosis and scoliosis on intervertebral disc extrusion in French bulldogs

Although thoracic vertebral malformations with kyphosis and scoliosis are often considered incidental findings on diagnostic imaging studies of screw-tailed brachycephalic breeds, they have been suggested to interfere with spinal biomechanics and intervertebral disc degeneration. It is however unknown if an abnormal spinal curvature also predisposes dogs to develop clinically relevant intervertebral disc herniations. The aim of this study was to evaluate if the occurrence of thoracic vertebral malformations, kyphosis or scoliosis would be associated with a higher prevalence of cervical or thoracolumbar intervertebral disc extrusion in French bulldogs

Scents from the Brazilian Cerrado: The essential oil from Calea hymenolepis (Asteraceae)

The Brazilian Cerrado is a savannah-like biome with more than 12,000 botanical species in Central Brazil. It is an endangered biome, and considered to be a biodiversity hotspot [1]. Calea hymenolepis Baker is a shrub native from the Cerrado. Samples from a population (n>5) were collected from a rupestrian field in the Chapada dos Veadeiros National Park, in Goiás State, Brazil. According to Brazilian law, collection and access were authorized by the Ministry of Environment (process IBAMA 02001.003166/2013-26). A voucher was deposited at the Embrapa Genetic Resources herbarium and the essential oil was obtained from the leaves by hydrodistillation for 2 h, using a Clevenger-type apparatus. The oil was analyzed by GC-FID and GC-MS on Agilent 7890A and 5975C systems, both with HP-5MS fused silica capillary columns (30 m x 0.25 mm x 0.25 μm). Oil components were identified by comparison of both mass spectra and linear retention indices with spectral libraries and literature. Oil yield was 0.2%. Major compounds present were α-phellandrene (34.2%), p-cymene (10.6%), germacrene D (8.5%), (E)-β-caryophyllene (6.3%) and δ-elemene (4.6%). The oil composition was quite different from other Calea, like C. clematidea, rich in clematerol, a terpenic epoxide [3]. Although subject to systematic phytochemical studies since the 1980's, with the identification of sesquiterpene lactones, chromones, benzopyrans, flavonoids, chalcones and even acetylenes, very few studies have been published regarding the essential oil of Calea species [2]. To the best of our knowledge, this is the first analysis on the essential oil from Calea hymenolepis

Scents from the Brazilian Cerrado: The essential oil from Siparuna brasiliensis (Siparunaceae)

Cerrado is a term used to describe a savannah-like vegetation, occurring in Central Brazil. It is considered one of the 25 most important biodiversity hotspots in the world and has numerous herbs, including several aromatic plant families, many of which have never been subjected to chemical study [1]. Siparuna brasiliensis (Spreng.) A. DC. (family Siparunaceae) is an endemic Brazilian species, occurring in both the Cerrado and the Atlantic Forest [2]. Differently from other Siparuna species, very few chemical data are available about S. brasiliensis, and none so far regarding its essential oil. During a systematic investigation on the Cerrado flora, S. brasiliensis (CEN herbarium voucher 88294) was sampled in Brasilia, Brazil, and the essential oil obtained by hydrodistillation. According to Brazilian law, collection and access were authorized by the Ministry of Environment (process IBAMA 02001.003166/2013-26). The oil was analyzed by GC-FID and GC-MS on Agilent 7890A and 5975C systems, both with HP-5MS fused silica capillary columns (30 m x 0.25 mm x 0.25 μm). Oil components were identified by comparison of both mass spectra and linear retention indices with spectral libraries and literature. Oil yield was 0.7%. Only 11 compounds were detected, all but one identified by mass spectra and retention indices. Most of the constituents were closely related sesquiterpenes, with gurjunane and guaiane skeletons. The major compound was cyclocolorenone (75.5%). Other components present were 11-hydroxy-3,5-guaiadiene (tentative identification), 2-tridecanone (3.6%), α-cadinol (3.4%) and viridiflorol (3.4%)

Observation of J/ψpJ/\psi p resonances consistent with pentaquark states in Λb0→J/ψK−p{\Lambda_b^0\to J/\psi K^-p} decays

Observations of exotic structures in the $J/\psi p$ channel, that we refer to as pentaquark-charmonium states, in $\Lambda_b^0\to J/\psi K^- p$ decays are presented. The data sample corresponds to an integrated luminosity of 3/fb acquired with the LHCb detector from 7 and 8 TeV pp collisions. An amplitude analysis is performed on the three-body final-state that reproduces the two-body mass and angular distributions. To obtain a satisfactory fit of the structures seen in the $J/\psi p$ mass spectrum, it is necessary to include two Breit-Wigner amplitudes that each describe a resonant state. The significance of each of these resonances is more than 9 standard deviations. One has a mass of $4380\pm 8\pm 29$ MeV and a width of $205\pm 18\pm 86$ MeV, while the second is narrower, with a mass of $4449.8\pm 1.7\pm 2.5$ MeV and a width of $39\pm 5\pm 19$ MeV. The preferred $J^P$ assignments are of opposite parity, with one state having spin 3/2 and the other 5/2.Comment: 48 pages, 18 figures including the supplementary material, v2 after referee's comments, now 19 figure

Precise measurements of the properties of the B-1(5721)(0,+) and B-2*(5747)(0,+) states and observation of B-+,B-0 pi(-,+) mass structures

Invariant mass distributions of B+π− and B0π+ combinations are investigated in order to study excited B mesons. The analysis is based on a data sample corresponding to 3.0 fb−1 of pp collision data, recorded by the LHCb detector at centre-of-mass energies of 7 and 8 TeV. Precise measurements of the masses and widths of the B1(5721)0,+ and B2(5747)0,+ states are reported. Clear enhancements, particularly prominent at high pion transverse momentum, are seen over background in the mass range 5850-6000 MeV in both B+π− and B0π+ combinations. The structures are consistent with the presence of four excited B mesons, labelled BJ (5840)0,+ and BJ (5960)0,+, whose masses and widths are obtained under different hypotheses for their quantum numbers

Quantum numbers of the X(3872)X(3872) state and orbital angular momentum in its ρ0Jψ\rho^0 J\psi decay

Angular correlations in $B^+\to X(3872) K^+$ decays, with $X(3872)\to \rho^0 J/\psi$, $\rho^0\to\pi^+\pi^-$ and $J/\psi \to\mu^+\mu^-$, are used to measure orbital angular momentum contributions and to determine the $J^{PC}$ value of the $X(3872)$ meson. The data correspond to an integrated luminosity of 3.0 fb$^{-1}$ of proton-proton collisions collected with the LHCb detector. This determination, for the first time performed without assuming a value for the orbital angular momentum, confirms the quantum numbers to be $J^{PC}=1^{++}$. The $X(3872)$ is found to decay predominantly through S wave and an upper limit of $4\%$ at $95\%$ C.L. is set on the fraction of D wave.Comment: 16 pages, 4 figure