Quantum Electrodynamics vacuum polarization solver

The self-consistent modeling of vacuum polarization due to virtual electron-positron fluctuations is of relevance for many near term experiments associated with high intensity radiation sources and represents a milestone in describing scenarios of extreme energy density. We present a generalized finite-difference time-domain solver that can incorporate the modifications to Maxwell's equations due to vacuum polarization. Our multidimensional solver reproduced in one dimensional configurations the results for which an analytic treatment is possible, yielding vacuum harmonic generation and birefringence. The solver has also been tested for two-dimensional scenarios where finite laser beam spot sizes must be taken into account. We employ this solver to explore different types of counter-propagating configurations that can be relevant for future planned experiments aiming to detect quantum vacuum dynamics at ultra-high electromagnetic field intensities

Majocchi’s Granuloma by Trichophytum rubrum in a kidney transplant patient - A case report

Introduction: Trichophytum rubrum is a filamentous fungus, with worldwide distribution, that usually causes superficial infections of skin and nails, namely tinea pedis, tinea corporis, tinea cruris and onychomycosis. Rarely, severe dermatophytosis can occur, presenting as deep dermatophytosis, Majocchi’s Granuloma or extensive dermatophytosis. Objectives and Methods: Case report of Majocchi’s Granuloma in a kidney transplant patient. Results: A case of a 55-year-old woman who underwent a kidney transplant 7 months before, under immunosuppressive therapy with tacrolimus and mycophenolate mofetil. She attended a Dermatology consultation to clarify skin lesions that appeared 6 months earlier. The skin exam revealed hard and painful plaque lesions on both legs, with an ulcer on the left leg lesion, violaceous papular lesions on the dorsum of the left foot and toes and a hard consistency nodule on the left leg. Some of the toe nails presented dystrophy or onycholysis. The patient denied any previous trauma or contact with plants or soil. Biopsies of lesions of the left leg and foot dorsum where sent for histology and mycological culture and toe nails for mycological culture. The histological examinations showed, in the reticular dermis and reaching the hypodermis, suppurative granulomas with multinucleated giant cells and areas of necrosis. PAS (Periodic Acid- Schiff) and GMS (Grocott’s Methenamine Silver) staining revealed multiple spores and septate hypha within the granulomas but not in the stratum corneum. No remnants of hair follicles where found. Culture of skin biopsies were positive for Tricophytum rubrum but nails´ culture was negative. Identification was further confirmed by sequencing of ITS region of ribosomal DNA (GenBank accession number MK967277). Oral Itraconazole 100mg bid and topic Sertoconazole where initiated. The patient was observed one month after and reported general malaise, tiredness, exertional dyspnea, whitish stools and increased abdominal volume. The physician chose to discontinue itraconazole and initiate oral terbinafine 250mg id. After two months on oral terbinafine, there was regression of the legs´ and left foot lesions with ulcer healing and disappearance of the left leg nodule. Conclusion: Diagnosis of deeper dermatophytosis is difficult, in part because there is no specific clinical presentation and, in many cases, it is even polymorphic. However, especially in patients with immunodeficiency, this hypothesis should be weighed. Confirmation is achieved by finding hyphae compatible with dermatophytes in the dermis and a positive culture for a dermatophyte. Treatment should include systemic antifungal agents, to which topical medication may be associated. Multiple therapeutic regimens have been proposed, but randomized trials or large case series are lacking. Antifungal therapy should be continued until the lesions are completely resolved. Surgical treatment has been reported as an option for highly localized lesions.info:eu-repo/semantics/publishedVersio

Search for Planetary Candidates within the OGLE Stars

We propose a method to distinguish between planetary and stellar companions to stars which present a periodic decrease in brightness, interpreted as a transit. Light curves from a total of 177 stars from the OGLE project were fitted by the model which simulates planetary transits using an opaque disk in front of an image of the Sun. The simulation results yield the orbital radius in units of stellar radii, the orbital inclination angle, and the ratio of the planet to the star radii. Combining Kepler's third law with a mass-radius relation for main sequence stars, it was possible to estimate values for the masses and radii of both the primary and secondary objects. This model was successfully tested with the confirmed planets orbiting the stars HD 209458, TrES-1, OGLE-TR-10, 56, 111, 113, and 132. The method consists of selecting as planetary candidates only those objects with primary densities between 0.7 and 2.3 solar densities (F, G, and K stars) and secondaries with radius less than 1.5 Jupiter radius. The method is not able to distinguish between a planet and a dwarf star with mass less than 0.1 $M_\odot$, such as OGLE-TR-122. We propose a selection of 28 planetary candidates (OGLE-TR-49, 51, 55, 63, 71, 76, 90, 97, 100, 109, 114, 127, 130, 131, 134, 138, 140, 146, 151, 155, 159, 164, 165, 169, 170, 171, 172, and 174) for high resolution spectroscopy follow up.Comment: 4 figures, 2 table

Vascular Endothelial Growth Factor (VEGF) Prevents the Downregulation of the Cholinergic Phenotype in Axotomized Motoneurons of the Adult Rat

Vascular endothelial growth factor (VEGF) was initially characterized by its activity on the vascular system. However, there is growing evidence indicating that VEGF also acts as a neuroprotective factor, and that its administration to neurons suffering from trauma or disease is able to rescue them from cell death. We questioned whether VEGF could also maintain damaged neurons in a neurotransmissive mode by evaluating the synthesis of their neurotransmitter, and whether its action would be direct or through its well-known angiogenic activity. Adult rat extraocular motoneurons were chosen as the experimental model. Lesion was performed by monocular enucleation and immediately a gelatine sponge soaked in VEGF was implanted intraorbitally. After 7 days, abducens, trochlear, and oculomotor nuclei were examined by immunohistochemistry against choline acetyltransferase (ChAT), the biosynthetic enzyme of the motoneuronal neurotransmitter acetylcholine. Lesioned motoneurons exhibited a noticeable ChAT downregulation which was prevented by VEGF administration. To explore whether this action was mediated via an increase in blood vessels or in their permeability, we performed immunohistochemistry against laminin, glucose transporter-1 and the plasmatic protein albumin. The quantification of the immunolabeling intensity against these three proteins showed no significant differences between VEGF-treated, axotomized and control animals. Therefore, the present data indicate that VEGF is able to sustain the cholinergic phenotype in damaged motoneurons, which is a first step for adequate neuromuscular neurotransmission, and that this action seems to be mediated directly on neurons since no sign of angiogenic activity was evident. These data reinforces the therapeutical potential of VEGF in motoneuronal diseases.España, MINECO and FEDER BFU2015-64515-PJunta de Andalucía and FEDER : P10-CVI605

Effects of a 4-week high-intensity interval training on pacing during 5-km running trial

This study analyzed the influence of a 4-week high-intensity interval training on the pacing strategy adopted by runners during a 5-km running trial. Sixteen male recreational long-distance runners were randomly assigned to a control group (CON, n = 8) or a high-intensity interval training group (HIIT, n = 8). The HIIT group performed high-intensity interval-training twice per week, while the CON group maintained their regular training program. Before and after the training period, the runners performed an incremental exercise test to exhaustion to measure the onset of blood lactate accumulation, maximal oxygen uptake (VO2max), and peak treadmill speed (PTS). A submaximal constant-speed test to measure the running economy (RE) and a 5-km running trial on an outdoor track to establish pacing strategy and performance were also done. During the 5-km running trial, the rating of perceived exertion (RPE) and time to cover the 5-km trial (T5) were registered. After the training period, there were significant improvements in the HIIT group of ∼7 and 5% for RE (P = 0.012) and PTS (P=0.019), respectively. There was no significant difference between the groups for VO2max (P = 0.495) or onset of blood lactate accumulation (P = 0.101). No difference was found in the parameters measured during the 5-km trial before the training period between HIIT and CON (P \u3e 0.05). These findings suggest that 4 weeks of HIIT can improve some traditional physiological variables related to endurance performance (RE and PTS), but it does not alter the perception of effort, pacing strategy, or overall performance during a 5-km running trial