Obturator externus abscess in a 9-year-old child: A case report and literature review.

Obturator pyomyositis is a rare condition in children. Diagnosis is often delayed because of its rarity, and the vagaries of its presentation cause it to be easily be missed. Physicians should therefore familiarize themselves with this condition and consider it as a possible differential diagnosis in patients presenting with an acutely painful hip. Inflammatory syndrome is also frequent among sufferers and the MRI is a very sensitive diagnostic tool for obturator pyomyositis. Additionally, joint fluid aspirations and blood cultures are also useful in identifying the pathogen. The appropriate antibiotic therapy provides a rapid regression of symptoms during the early stage of pyomyositis. In cases of MRI-confirmed abscess, surgical treatment is indicated. Our report focuses on a case of obturator pyomyositis in a 9-year-old boy. The child was febrile for 5 days and could only manage to walk a few steps. His hip range of motion was restricted in all directions. In addition, the patient had presented pain and swelling of his right elbow for a day, with a restriction of motion in the joint. There was a clear inflammatory syndrome. A diagnosis of hip and elbow septic arthritis was suspected, and the child underwent joint aspiration of the both cited joints. The aspiration of the elbow returned pus. Conversely, no effusion was found in the hip aspiration. The administration of empiric intravenous antibiotherapy was started. An MRI revealed an osteomyelitis of the ischio-pubic area associated with a subperiosteal abscess. Subsequently, 3 days after elbow arthrotomy, a surgical treatment was performed on the patient's right hip in order to evacuate the subperiosteal abscess and muscular collection because of the persistence of the patient's symptoms and inflammatory syndrome despite susceptible intravenous antibiotics. Postsurgery the patient showed steady improvement. Such cases demonstrate how diagnosis can be difficult because pelvic pyomyositis is often mistaken for more common pathologies such as septic arthritis, osteomyelitis, or appendicitis. This may delay the diagnosis or refer misdiagnosis. We discuss this rare infection in light of the literature with particular reference to its incidence, clinical features, bacteriological etiology, biological, and radiological presentation, and above all, its treatment

Aluminum and iron can be deposited in the calcified matrix of bone exostoses.

Exostosis (or osteochondroma) is the most common benign bone tumor encountered in children and adults. Exostoses may occur as solitary or multiple tumors (in the autosomal syndromes of hereditary multiple exostoses). Exostoses are composed of cortical and medullary bone covered by an overlying hyaline cartilage cap. We have searched iron (Fe) and aluminum (Al) in the matrix of cortical and trabecular bone of 30 patients with exostosis. Al3 + and Fe3 + are two cations which can substitute calcium in the hydroxyapatite crystals of the bone matrix. The bone samples were removed surgically and were studied undecalcified. Perls\u27 Prussian blue staining (for Fe) and solochrome azurine B (for Al) were used on the histological sections of the tumors. Al3 + was detected histochemically in 21/30 patients as linear bands deposited by the osteoblasts. Fe3 + was detected in 10 out of these 21 patients as linear bands in the same locations. Fe3 + and Al3 + were not identified in the bone matrix of a control group of 20 osteoporotic patients. Energy X-ray Dispersive Spectrometry failed to identify Fe and Al in bone of these tumors due to the low sensitivity of the method. Wavelength Dispersive Spectrometry identified them but the concentrations were very low. Histochemistry appears a very sensitive method for Fe3 + and Al3 + in bone.The presence of these two metals in the exostoses advocates for a disturbed metabolism of osteoblasts which can deposit these metals into the bone matrix, similar to which is observed in case of hemochromatosis with Fe3 +

Exocomets from a Solar System Perspective

Exocomets are small bodies releasing gas and dust which orbit stars other than the Sun. Their existence was first inferred from the detection of variable absorption features in stellar spectra in the late 1980s using spectroscopy. More recently, they have been detected through photometric transits from space, and through far-IR/mm gas emission within debris disks. As (exo)comets are considered to contain the most pristine material accessible in stellar systems, they hold the potential to give us information about early stage formation and evolution conditions of extra solar systems. In the solar system, comets carry the physical and chemical memory of the protoplanetary disk environment where they formed, providing relevant information on processes in the primordial solar nebula. The aim of this paper is to compare essential compositional properties between solar system comets and exocomets to allow for the development of new observational methods and techniques. The paper aims to highlight commonalities and to discuss differences which may aid the communication between the involved research communities and perhaps also avoid misconceptions. The compositional properties of solar system comets and exocomets are summarized before providing an observational comparison between them. Exocomets likely vary in their composition depending on their formation environment like solar system comets do, and since exocomets are not resolved spatially, they pose a challenge when comparing them to high fidelity observations of solar system comets. Observations of gas around main sequence stars, spectroscopic observations of “polluted” white dwarf atmospheres and spectroscopic observations of transiting exocomets suggest that exocomets may show compositional similarities with solar system comets. The recent interstellar visitor 2I/Borisov showed gas, dust and nuclear properties similar to that of solar system comets. This raises the tantalising prospect that observations of interstellar comets may help bridge the fields of exocomet and solar system comets

Biofuels Policy in Europe Under the Directive 2003/30: An Analysis of Goals, Hindrances, Instruments and Effects

Up to 2008/2009, biofuels were considered one of the best alternatives to oil consumption in a captive market like transports, being one of the pillars of the 20-20-20 initiative in Europe. Improvement of security of supply through partial substitution of imported oil; reduction of GHGs emissions; improvement of income and employment in the agricultural and rural sectors were the main drivers of the promotion of biofuels in Europe, as well as in the United States and in Brazil. In the European Union biofuels policy was supported through Directive 2003/30. However its effects proved to be disappointing: the consumption of biofuels was expected by the Directive to account for 5.75% share of road fuels in 2010 in the European MSs, but it came early clear that such a target could not be met. Above all, consensus about biofuels decreased sharply when their ability to strongly decrease overall GHGs emissions was questioned, and when they were blamed of being the main responsible of the 2007-2008 food price increase. Finally, a new Directive was approved on April 23rd, 2009, including the request of various certifications to prove the sustainability of biofuels. The paper deals deeply with the biofuel experience in Europe, providing a general analysis of the 2003/30 Directive. It includes an evaluation of the difficulties met in satisfying the requested targets, an assessment of the MSs policies to support biofuels, and a discussion about the main features of the (failed) birth of a new industry

Future Exoplanet Research: Science Questions and How to Address Them

Started approximately in the late 1980s, exoplanetology has up to now unveiled the main gross bulk characteristics of planets and planetary systems. In the future it will benefit from more and more large telescopes and advanced space missions. These instruments will dramatically improve their performance in terms of photometric precision, detection speed, multipixel imaging, high-resolution spectroscopy, allowing to go much deeper in the knowledge of planets. Here we outline some science questions which should go beyond these standard improvements and how to address them. Our prejudice is that one is never too speculative: experience shows that the speculative predictions initially not accepted by the community have been confirmed several years later (like spectrophotometry of transits or circumbinary planets).Comment: Invited review, accepte

The First Post-Kepler Brightness Dips of KIC 8462852

We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in October 2015, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1-2.5% dips, named "Elsie," "Celeste," "Skara Brae," and "Angkor", which persist on timescales from several days to weeks. Our main results so far are: (i) there are no apparent changes of the stellar spectrum or polarization during the dips; (ii) the multiband photometry of the dips shows differential reddening favoring non-grey extinction. Therefore, our data are inconsistent with dip models that invoke optically thick material, but rather they are in-line with predictions for an occulter consisting primarily of ordinary dust, where much of the material must be optically thin with a size scale <<1um, and may also be consistent with models invoking variations intrinsic to the stellar photosphere. Notably, our data do not place constraints on the color of the longer-term "secular" dimming, which may be caused by independent processes, or probe different regimes of a single process

Special cases : moons, rings, comets, trojans

Non-planetary bodies provide valuable insight into our current under- standing of planetary formation and evolution. Although these objects are challeng- ing to detect and characterize, the potential information to be drawn from them has motivated various searches through a number of techniques. Here, we briefly review the current status in the search of moons, rings, comets, and trojans in exoplanet systems and suggest what future discoveries may occur in the near future.Comment: Invited review (status August 2017