On optimal matching measures for matching problems related to the Euclidean distance

summary:We deal with an optimal matching problem, that is, we want to transport two measures to a given place (the target set) where they will match, minimizing the total transport cost that in our case is given by the sum of two different multiples of the Euclidean distance that each measure is transported. We show that such a problem has a solution with an optimal matching measure supported in the target set. This result can be proved by an approximation procedure using a $p$-Laplacian system. We prove that any optimal matching measure for this problem is supported on the boundary of the target set when the two multiples that affect the Euclidean distances involved in the cost are different. Moreover, we present simple examples showing uniqueness or non-uniqueness of the optimal measure

A nonlocal 1-Laplacian problem and median values

In this paper, we study solutions to a nonlocal 1-Laplacian equation. We introduce two notions of solution and prove that the weaker of the two concepts is equivalent to a nonlocal median value property, where the median is determined by a measure related to J. We also show that solutions in the stronger sense are nonlocal analogues of local least gradient functions, in the sense that they minimize a nonlocal functional. In addition, we prove that solutions in the stronger sense converge to least gradient solutions when the kernel J is appropriately rescaled

Niche differentiation mechanisms among canopy frugivores and zoochoric trees in the northeastern extreme of the Amazon

Frugivores and zoocoric trees represent an important proportion of tropical rainforest biodiversity. As niche differences favor species coexistence, we aimed to evaluate morphological and temporal niche segregation mechanisms among zoochoric trees and canopy frugivores in a tropical rainforest in the northeastern extreme of the Brazilian Amazon. We tested the effects of fruit morphology, tree size, frugivore body size and time of day on fruit consumption. We recorded the frugivore species that fed on 72 trees (44 species, 22 genera) and whether these frugivores swallowed the seeds. We monitored trees only once from 07:00 to 17:00 h between January and September 2017. We observed fruit consumption in 20 of the 72 trees. Seventy-three frugivore individuals from 22 species visited the trees. Heavier fruits were consumed by larger frugivores, while seed size was inversely correlated with frugivore size. Narrower fruits and fruits with smaller seeds had greater probability of having their seeds ingested, and larger frugivores were more prone to ingest seeds. Trees bearing fruits with smaller seeds were visited by a greater number of frugivores. Taxonomic groups differed in the time of arrival at fruiting trees. None of the evaluated variables (fruit weight and size, and seed size) affected the richness of frugivores that visited the trees. We concluded that, in the studied forest, fruit morphology (weight, size and seed size) is a niche segregation mechanism among zoochoric trees, while body size and time of day are niche segregation mechanisms among frugivores.info:eu-repo/semantics/publishedVersio

A nonlocal 1-Laplacian problem and median values

In this paper, we study solutions to a nonlocal 1-Laplacian equation. We introduce two notions of solution and prove that the weaker of the two concepts is equivalent to a nonlocal median value property, where the median is determined by a measure related to J. We also show that solutions in the stronger sense are nonlocal analogues of local least gradient functions, in the sense that they minimize a nonlocal functional. In addition, we prove that solutions in the stronger sense converge to least gradient solutions when the kernel J is appropriately rescaled

The usage of Bupivacaina as anesthetic agent in knee arthroscopy.

Introduction: Artroscopy of the knee is a procedure that is frequently developed as a diagnostic and therapeutic means in patients who suffer among other diseases, from chronic sinuvitis, lesions of the meniscus and adherence . A great number of these patients receive medical assistance at the outpatient department of the orthopaedic department where the need of its use is assessed. It is a relatively short procedure that has few risks when it is performed with the appropriate technique. Objective: To show the use of intra articular Bupivacaine 0,25 % in the artroscopy of the knee. Method: Retrospective study carried out at the University Hospital ¨Dr. Gustavo Aldereguía Lima¨ from Cienfuegos province from September 2002 to February 2003. This study was developed with 20 patients who were initially assisted at the service of Orthopaedics in which a group of therapeutic procedures were decided. Bupivacaine 0,25 % together with Epinephrine 0,1 % in a dose of 0,1 ml were injected in the intra articular space in a volume of 20 ml distributed in 4 sections with 5 ml each. At the level of the section where the artroscope was inserted , 5 ml of Bupivacaine 0,25 % was applied. Result: the age of the patient ranged 30 to 61 years of age with a media of 44,6 years and a standard deviation of 12,6 years. The introduction and application of the procedure throughout artroscopy was possible in al patients. Conclusion: Bupivacaine is a good local anaesthetic because of its slow action since the onset of application and its prolonged duration, and because of the intensity and the duration of the sensorial block that is superior to the motor block

Endobronchial solitary fibrous tumor

Solitary fibrous tumor (SFT) is a mesenchymal neoplasm that appears primarily in the pleura and rarely in intrapulmonary or endobronchial topography. The authors report the case of a 47-year-old woman who presented obstructive respiratory symptoms for 4 years. The chest computed tomography and bronchoscopy showed an obstructive polypoid lesion located between the trachea and the left main bronchus associated with distal atelectasis of the left lung. A resection of the lesion was performed and, macroscopically, the mass was oval, encapsulated, and firm, measuring 2.3 × 1.7 × 1.5 cm. Histology revealed low-grade mesenchymal spindle cell neoplasm, with alternating cellularity, myxoid areas, and mature adipose tissue outbreaks, as well as blood vessels with irregular walls. The immunohistochemical study was positive for CD34, CD99, and BCL2. The diagnosis was SFT in an unusual topography. The patient’s symptoms remitted after tumor excision, and no systemic problems were evident. SFTs primarily affect adults and often follow a benign course; however, their behavior is unpredictable. The presence of necrosis and mitotic activity may portend a poor prognosis. Endobronchial SFTs are rare but should be evaluated and monitored similar to SFTs at other sites, with a long-term follow-u

Oral leucine supplementation is sensed by the brain but neither reduces food intake nor induces an anorectic pattern of gene expression in the hypothalamus

Leucine activates the intracellular mammalian target of the rapamycin (mTOR) pathway, and hypothalamic mTOR signaling regulates food intake. Although central infusion of leucine reduces food intake, it is still uncertain whether oral leucine supplementation is able to affect the hypothalamic circuits that control energy balance. We observed increased phosphorylation of p70s6k in the mouse hypothalamus after an acute oral gavage of leucine. We then assessed whether acute oral gavage of leucine induces the activation of neurons in several hypothalamic nuclei and in the brainstem. Leucine did not induce the expression of Fos in hypothalamic nuclei, but it increased the number of Fos-immunoreactive neurons in the area postrema. In addition, oral gavage of leucine acutely increased the 24 h food intake of mice. Nonetheless, chronic leucine supplementation in the drinking water did not change the food intake and the weight gain of ob/ob mice and of wild-type mice consuming a low- or a high-fat diet. We assessed the hypothalamic gene expression and observed that leucine supplementation increased the expression of enzymes (BCAT1, BCAT2 and BCKDK) that metabolize branched-chain amino acids. Despite these effects, leucine supplementation did not induce an anorectic pattern of gene expression in the hypothalamus. In conclusion, our data show that the brain is able to sense oral leucine intake. However, the food intake is not modified by chronic oral leucine supplementation. These results question the possible efficacy of leucine supplementation as an appetite suppressant to treat obesitySão Paulo Research Foundation (FAPESP, 2010/18086-0)São Paulo Research Foundation (FAPESP, 2012/15517-6)International Brain Research Organization (IBRO

Involvement of the subthalamic nucleus in impulse control disorders associated with Parkinson’s disease

Behavioural abnormalities such as impulse control disorders may develop when patients with Parkinson’s disease receive dopaminergic therapy, although they can be controlled by deep brain stimulation of the subthalamic nucleus. We have recorded local field potentials in the subthalamic nucleus of 28 patients with surgically implanted subthalamic electrodes. According to the predominant clinical features of each patient, their Parkinson’s disease was associated with impulse control disorders (n = 10), dyskinesias (n = 9) or no dopaminergic mediated motor or behavioural complications (n = 9). Recordings were obtained during the OFF and ON dopaminergic states and the power spectrum of the subthalamic activity as well as the subthalamocortical coherence were analysed using Fourier transform-based techniques. The position of each electrode contact was determined in the postoperative magnetic resonance image to define the topography of the oscillatory activity recorded in each patient. In the OFF state, the three groups of patients had similar oscillatory activity. By contrast, in the ON state, the patients with impulse control disorders displayed theta-alpha (4–10 Hz) activity (mean peak: 6.71 Hz) that was generated 2–8mm below the intercommissural line. Similarly, the patients with dyskinesia showed theta-alpha activity that peaked at a higher frequency (mean: 8.38 Hz) and was generated 0–2mm below the intercommissural line. No such activity was detected in patients that displayed no dopaminergic side effects. Cortico-subthalamic coherence was more frequent in the impulsive patients in the 4–7.5 Hz range in scalp electrodes placed on the frontal regions anterior to the primary motor cortex, while in patients with dyskinesia it was in the 7.5–10 Hz range in the leads overlying the primary motor and supplementary motor area. Thus, dopaminergic side effects in Parkinson’s disease are associated with oscillatory activity in the theta-alpha band, but at different frequencies and with different topography for the motor (dyskinesias) and behavioural (abnormal impulsivity) manifestations. These findings suggest that the activity recorded in parkinsonian patients with impulse control disorders stems from the associative-limbic area (ventral subthalamic area), which is coherent with premotor frontal cortical activity. Conversely, in patients with L-dopa-induced dyskinesias such activity is recorded in the motor area (dorsal subthalamic area) and it is coherent with cortical motor activity. Consequently, the subthalamic nucleus appears to be implicated in the motor and behavioural complications associated with dopaminergic drugs in Parkinson’s disease, specifically engaging different anatomo-functional territories