Magnetic Reconnection, Cosmic Ray Acceleration, and Gamma-Ray emission around Black Holes and Relativistic Jets

Particle acceleration by magnetic reconnection is now recognized as an important process in magnetically dominated regions of galactic and extragalactic black hole sources. This process helps to solve current puzzles specially related to the origin of the very high energy flare emission in these sources. In this review, we discuss this acceleration mechanism and show recent analytical studies and multidimensional numerical SRMHD and GRMHD (special and general relativistic magnetohydrodynamical) simulations with the injection of test particles, which help us to understand this process both in relativistic jets and coronal regions of these sources. The very high energy and neutrino emission resulting from the accelerated particles by reconnection is also discussed.Comment: Invited Review at the International Conference on Black Holes as Cosmic Batteries: UHECRs and Multimessenger Astronomy - BHCB2018, 12-15 September, 2018, Foz du Iguazu, Brasil, in press in Procs. of Science. arXiv admin note: text overlap with arXiv:1608.0317

A first report on the efficacy of a single intra-articular administration of blood cell secretome, triamcinolone acetonide, and the combination of both in dogs with osteoarthritis

Research Areas: Veterinary SciencesBackground: Osteoarthritis represents a signifcant welfare problem for many dogs, with limited therapeutic options other than palliative pain control. To evaluate the efect of the intra-articular administration of blood cell secretome and triamcinolone, 15 dogs with bilateral hip osteoarthritis were randomly assigned to a blood cell secretome (BCSG, n=5), triamcinolone (TG) or their combination group (BCS+TG, n=5). BCSG received a single intra-articular administration of 3 ml of blood cell secretome, TG 0.5 ml of triamcinolone acetonide 40 mg/ml, and BCS+TG received the combined products. The volume to administrate was corrected to 3.5 ml with saline. On days 0, 8, 15, 30, 60, 90, 120, 150, and 180, a copy of the Canine Brief Pain Inventory (divided into pain interference score—PIS and Pain Severity Score—PSS), Liverpool Osteoarthritis in Dogs (LOAD), Hudson Visual Analogue Scale (HVAS), and Canine Orthopedic Index (COI, divided into function, gait, stifness, and quality of life) was completed. Results were analyzed with the Kruskal–Wallis test and the Kaplan–Meier estimators were conducted and compared with the Log Rank test, p<0.05. Results: Animals in the sample had a mean age of 9.0±2.9 years and a bodyweight of 28.8±4.1 kg. Hips were classifed as moderate (8) and severe (7) osteoarthritis. No diferences were found between groups at T0 regarding considered evaluations. Signifcant diferences were observed between groups in pain scores from+8d-+150d, with BCS+TG exhibiting better results. The same was observed for HVAS and LOAD, from+8d-+120d. Improvements were also observed in several dimensions of the COI. Kaplan–Meier estimators showed that BCS+TG produced longer periods with better results, followed by BCSG and TG. Conclusion: The intra-articular administration of blood cell secretome improved the clinical signs and scores of several clinical metrology instruments in dogs with hip OA, particularly when combined with triamcinolone. Further studies are required.info:eu-repo/semantics/publishedVersio

Risks of Maternal Obesity in Pregnancy: A Case-control Study in a Portuguese Obstetrical Population

Objective The present study aims to understand to what extent obesity is related to adverse maternal, obstetrical, and neonatal outcomes in a Portuguese obstetrical population. Methods A retrospective case-control study was conducted at the Department of Obstetrics of a differentiated perinatal care facility. The study compared 1,183 obese pregnant women with 5,399 normal or underweight pregnant women for the occurrence of gestational diabetes, hypertensive pregnancy disorders, and preterm birth. Mode of delivery, birthweight, and neonatal intensive care unit (ICU) admissions were also evaluated. Mean blood glucose values were evaluated and compared between groups, in the first and second trimesters of pregnancy. Only singleton pregnancies were considered. Results The prevalence of obesity was 13.6%. Obese pregnant women were significantly more likely to have cesarean sections (adjusted odds ratio [aOR] 2.0, p < 0.001), gestational diabetes (aOR 2.14, p < 0.001), hypertensive pregnancy disorders (aOR 3.43, p < 0.001), and large-for-gestational age or macrosomic infants (aOR 2.13, p < 0.001), and less likely to have small-for-gestational age newborns (aOR 0.51, p < 0.009). No significant differences were found in terms of preterm births, fetal/neonatal deaths, low birthweight newborns, and neonatal ICU admissions among cases and controls. Maternal obesity was significantly associated with higher mean blood glucose levels, in the first and second trimesters of pregnancy. Conclusion Obesity is associated with increased risks of adverse pregnancy and neonatal outcomes. These risks seem to increase progressively with increasing body mass index (BMI) class. Female obesity should be considered a major public health issue and has consequences on maternal-fetal health

Characterization of weight-bearing compensation in dogs with bilateral hip osteoarthritis

Área de pesquisa: Veterinary SciencesTo describe the weight-bearing compensation in working dogs with bilateral hip osteoarthritis (OA), 50 police working dogs were evaluated with a weight distribution platform at the initial evaluation and after intra-articular treatment (a negative control 0.9% sodium chloride (NaCl), a platelet concentrate, Hylan G-F 20, triamcinolone hexacetonide or stanozolol). Six evaluation sessions were performed, over a 180-day period. Results were compared by breed, age, sex, weight and Orthopedic Foundation for Animals hip grade scores with the Independent Samples T-Test, repeated samples Analysis of variance and Pearson correlation coefficient, P < .05. Animals had a mean age of 6.5 § 2.4 years and a bodyweight of 26.7 § 5.2kg. No significant differences were observed when comparing weight-bearing for different breeds, sex, hip grades or weight during the initial evaluation. Significant differences were observed in deviation (P < .01) and symmetry index (P < .01) between the control and treatment groups during the follow-up period. A weight shift from pelvic to thoracic limbs was observed, with a weak, although a significant, correlation between a pelvic limb and the opposing contralateral thoracic limb. Labrador Retrievers showed higher symmetry index and deviation from normal values during the follow-up period than German Shepherd Dogs and Dutch Shepherd Dogs. Male dogs also showed higher symmetry index and deviation compared with females. At this period, the symmetry index showed a weak, although significant, correlation with body weight. Weight-bearing of all limbs correlated with the remaining limbs, reflecting a more balanced weight distribution than the initial evaluation. The weight distribution platform can be used to evaluate patients, at the initial presentation and during the assessment of response to treatment.info:eu-repo/semantics/publishedVersio

Minimal clinically-important differences for the "Liverpool Osteoarthritis in Dogs" (LOAD) and the "Canine Orthopedic Index" (COI) in dogs with osteoarthritis.

ObjectiveOsteoarthritis is the most common joint disease in companion animals. Several client-report outcome measures (CROMs) have been developed and validated to monitor patients and their response to treatment. However, estimates for minimal clinically-important differences for these CROMs in the context of osteoarthritis have not been published.Patients and methodsData from the Clínica Veterinária de Cães (Portuguese Gendarmerie Canine Clinic) clinical records were extracted. Baseline and 30-day post-treatment follow-up data from 296 dogs treated for hip osteoarthritis were categorized based on an anchor question, and estimates of minimal clinically-important differences (MCIDs) using distribution-based and anchor-based methods were performed.ResultsFor the LOAD, the anchor-based methods provided a MCID estimate range of -2.5 to -9.1 and the distribution-based methods from 1.6 to 4.2. For the COI, the anchor-based methods provided a MCID estimate range of -4.5 to -16.6 and the distribution-based methods from 2.3 to 2.4. For the dimensions of COI, values varied from -0.5 to -4.9 with the anchor-based methods and from 0.6 to 2.7 with the distribution-based methods. Receiver operator characteristic curves provided areas under the curve >0.7 for the COI, indicating an acceptable cut-off point, and >0.8 for the LOAD, indicating an excellent cut-off point.ConclusionOur estimates of MCIDs for dogs with OA were consistent with previously proposed values of -4 for the LOAD and -14 for the COI in a post-surgical intervention context. ROC curve data suggest that LOAD may more reliably differentiate between anchor groups. We also presented estimates from COI of -4 for Stiffness, Function, and Gait and -3 for quality of life. These estimates can be used for research and patient monitoring

Morphologic and Molecular Features of Hepatocellular Adenoma with Gadoxetic Acid-enhanced MR Imaging

Purpose To evaluate the diagnostic performance of imaging features of gadoxetic acid-enhanced magnetic resonance (MR) imaging to differentiate among hepatocellular adenoma (HCA) subtypes by using the histopathologic results of the new immunophenotype and genotype classification and to correlate the enhancement pattern on the hepatobiliary phase (HBP) with the degrees of expression of organic anion transporting polypeptide (OATP1B1/3), multidrug resistance-associated protein 2 (MRP) (MRP2), and MRP 3 (MRP3) transporters. Materials and Methods This retrospective study was approved by the institutional review board, and the requirement for informed consent waived. MR imaging findings of 29 patients with 43 HCAs were assessed by two radiologists independently then compared with the histopathologic analysis as the standard of reference. Receiver operating characteristic curves and Spearman rank correlation coefficient were used to test the diagnostic performance of gadoxetic acid-enhanced MR imaging features, which included the retention or washout at HBP and degree of transporter expression. Interreader agreement was assessed by using the κ statistic with 95% confidence interval. Results The area under the curve for the diagnosis of inflammatory HCA was 0.79 (95% confidence interval: 0.64, 0.90); for the steatotic type, it was 0.90 (95% confidence interval: 0.77, 0.97); and for the β-catenin type, it was 0.87 (95% confidence interval: 0.74, 0.95). There were no imaging features that showed a significant statistical correlation for the diagnosis of unclassified HCAs. On immunohistochemical staining, OATP1B1/3 expression was the main determinant for the retention, whereas MRP3 was the key determinant for washout of gadoxetic acid at HBP (P < .001). MRP2 appeared to have no role. Conclusion Gadoxetic acid-enhanced MR imaging features may suggest the subtype of HCA. The degree of OATP1B1/3 and MRP3 expression correlated statistically with gadoxetic acid retention and washout, respectively, in the HBP. (©) RSNA, 2015 Online supplemental material is available for this article

Simulations of extensional flow in microrheometric devices

We present a detailed numerical study of the flow of a Newtonian fluid through microrheometric devices featuring a sudden contraction–expansion. This flow configuration is typically used to generate extensional deformations and high strain rates. The excess pressure drop resulting from the converging and diverging flow is an important dynamic measure to quantify if the device is intended to be used as a microfluidic extensional rheometer. To explore this idea, we examine the effect of the contraction length, aspect ratio and Reynolds number on the flow kinematics and resulting pressure field. Analysis of the computed velocity and pressure fields show that, for typical experimental conditions used in microfluidic devices, the steady flow is highly three-dimensional with open spiraling vortical structures in the stagnant corner regions. The numerical simulations of the local kinematics and global pressure drop are in good agreement with experimental results. The device aspect ratio is shown to have a strong impact on the flow and consequently on the excess pressure drop, which is quantified in terms of the dimensionless Couette and Bagley correction factors. We suggest an approach for calculating the Bagley correction which may be especially appropriate for planar microchannels