Multi-frequency study of DEM L299 in the Large Magellanic Cloud

We have studied the HII region DEM L299 in the Large Magellanic Cloud to understand its physical characteristics and morphology in different wavelengths. We performed a spectral analysis of archived XMM-Newton EPIC data and studied the morphology of DEM L299 in X-ray, optical, and radio wavelengths. We used H alpha, [SII], and [OIII] data from the Magellanic Cloud Emission Line Survey and radio 21 cm line data from the Australia Telescope Compact Array (ATCA) and the Parkes telescope, and radio continuum data from ATCA and the Molonglo Synthesis Telescope. Our morphological studies imply that, in addition to the supernova remnant SNR B0543-68.9 reported in previous studies, a superbubble also overlaps the SNR in projection. The position of the SNR is clearly defined through the [SII]/H alpha flux ratio image. Moreover, the optical images show a shell-like structure that is located farther to the north and is filled with diffuse X-ray emission, which again indicates the superbubble. Radio 21 cm line data show a shell around both objects. Radio continuum data show diffuse emission at the position of DEM L299, which appears clearly distinguished from the HII region N 164 that lies south-west of it. We determined the spectral index of SNR B0543-68.9 to be alpha=-0.34, which indicates the dominance of thermal emission and therefore a rather mature SNR. We determined the basic properties of the diffuse X-ray emission for the SNR, the superbubble, and a possible blowout region of the bubble, as suggested by the optical and X-ray data. We obtained an age of 8.9 (3.5-18.1) kyr for the SNR and a temperature of 0.64 (0.44-1.37) keV for the hot gas inside the SNR, and a temperature of the hot gas inside the superbubble of 0.74 (0.44-1.1) keV. We conclude that DEM L299 consists of a superposition of SNR B0543-68.9 and a superbubble, which we identified based on optical data.Comment: Accepted for publication in Astronomy and Astrophysics. 17 pages, 16 figure

L’Invention de Morel. Robinson, les choses et les simulacres

L'Invention de Morel, roman de l'écrivain argentin Alfonso Bioy Casares, a été écrit en 1940. Il met en scène une variante de ce que propose la robin-sonnade, à savoir la rencontre d'un homme et d'une île déserte. À ceci près que l'île n'est pas vraiment déserte, elle est peuplée de spectres singuliers, produits par une machine à illusions. Le narrateur, après bien des déboires, après des peurs devant les apparitions de ces Vendredis virtuels, va tomber amoureux de l'image d'une des femmes ainsi holographiée et tentera de partager son univers virtuel en s'introduisant dans une séquence de son monde, par la même technologie qui l'a tuée pour la transformer en hologramme. Ce récit interroge notre époque sur son rapport à la réalité et aux idéologies.Morel's Invention was written in 1940 by the Argentine Alfonso Bioy Casares. It stages another version of a Robinson Crusoe type of narrative — a story about a man's meeting with a desert island. Not exactly desert though, because it is actually peopled with peculiar ghosts, produced by an illusion-making machine. After suffering many setbacks as he fears those apparitions of virtual Fridays, the narrator falls in love with the picture of one of these holographed women. He makes his best to share her virtual universe by struggling into a sequence of her world, resorting to the very same technique that had killed her and made an hologram of her. This novel questions our time on the relationship between reality and ideologies

Radio-Continuum Observations Of Small, Radially Polarised Supernova Remnant J0519-6902 In The Large Magellanic Cloud

We report on new Australian Telescope Compact Array (ATCA) observations of SNR J0519-6902. The Supernova Remnant (SNR) is small in size (~8 pc) and exhibits a typical SNR spectrum of alpha = -0.53 +- 0.07, with steeper spectral indices found towards the northern limb of the remnant. SNR J0519-6902 contains a low level of radially orientated polarisation at wavelengths of 3 & 6 cm, which is characteristic of younger SNRs. A fairly strong magnetic field was estimated of ~171 microG. The remnant appears to be the result of a typical Type Ia supernovae, sharing many properties as another small and young Type Ia LMC SNR, J0509-6731.Comment: 10 pages 7 figures, submitted to Serbian Astronomical Journa

Aneurysmatic Subdural Haemorrhage: Brief Review

Acute subdural hemorrhage caused by a ruptured intracranial aneurysm is a well-known association but usually linked to dismal outcome. We briefly reviewed the clinical and imaging features, surgical management and outcome of 45 patients with subdural bleeding related to intracranial aneurysm. Forty-two reports were encountered in the literature between 1981-2015 and three additional patients were identified in the author personal archives. A total of three patients had bilateral acute subdural hemorrhage, and the epidural hematoma was not present in any of the 45 reports. Coma was identified in 32/45 (71%) patients at admission. Only seven of 45 cases reported were managed by endovascular approach. A good clinical outcome was observed in 23/45 (51%) and early mortality occurred in 10/45 (22%) of the patients analysed. Neurosurgical management has evolved tremendously in recent years leading to more comprehensive understanding about this association. Factors leading to natural history, mechanisms, imaging aspects and improvement of clinical results of aneurysmatic subdural bleeding merit further studies

Radio-continuum study of Large Magellanic Cloud Supernova Remnant J0509-6731

We present a detailed study of Australia Telescope Compact Array (ATCA) observations ($\lambda$ = 20, 13, 6 & 3~cm) of supernova remnant (SNR) J0509--6731 in the Large Magellanic Cloud (LMC). The remnant has a ring morphology with brightened regions towards the south-western limb. We also find a second brightened inner ring which is only seen in the radio-continuum. The SNR is almost circular, with a diameter ranging from 7 to 8~pc, and a steep radio spectral index between 36 and 3~cm of $\alpha=-0.73\pm0.02$, which is characteristic of younger SNRs. We also report detection of radially orientated polarisation across the remnant at 6~cm, with a mean fractional polarisation level of $P\cong$~(26~$\pm$~13)%. We find the magnetic field ($\sim$168~$\mu$G) and $\Sigma - D$ ($\Sigma =$ $1.1\times 10^{-19}$~W m$^{-2}$~Hz$^{-1}$~sr$^{-1}$ , $D=$ 7.35~pc) to be consistent with other young remnants

Multifrequency radio observations of SNR J0536-6735 (N 59B) with associated pulsar

We present a study of new Australian Telescope Compact Array (ATCA) observations of supernova remnant, SNR J0536-6735. This remnant appears to follow a shell morphology with a diameter of D=36x29 pc (with 1 pc uncertainty in each direction). There is an embedded Hii region on the northern limb of the remnant which made various analysis and measurements (such as flux density, spectral index and polarisation) difficult. The radio-continuum emission followed the same structure as the optical emission, allowing for extent and flux density estimates at 20 cm. We estimate a surface brightness for the SNR at 1 GHz of 2.55x10^-21 W m^-2 Hz^-1 sr^-1. Also, we detect a distinctive radio-continuum point source which confirms the previous suggestion of this remnant being associated with a pulsar wind nebulae (PWN). The tail of this remnant isn't seen in the radio-continuum images and is only seen in the optical and X-ray images.Comment: 10 pages 4 figures, accepted for publication in SA

Effects of Pidotimod and Bifidobacteria Mixture on Clinical Symptoms and Metabolomic Profile of Children with Recurrent Respiratory Infections: a Randomized Placebo Controlled Trial

BACKGROUND: Many preschool children develop recurrent respiratory tract infections (RRI). Strategies to prevent RRI include the use of immunomodulators, as pidotimod or probiotics, but there is limited evidence on the clinical effects of the treatment, alone or combined, as well as on the changes of urine metabolic profile following it. OBJECTIVES. To investigate whether the treatment with pidotimod and/or bifidobacteria were associated with 1) a reduced morbidity related to RRI and 2) differences in the urine metabolic profile. MATERIALS AND METHODS: The study is a four-arm, exploratory, prospective, randomized, double-blinded, placebo-controlled clinical trial conducted during 2 autumn seasons, over the same three-months periods in 2 consecutive years. Children aged 3-6 years with RRI who attended the nursery school were enrolled and randomly assigned to one of the 4 arms to receive active medications or placebos for the first 10 days of each month for 4 consecutive months. Metabolomic analyses on urine samples collected before and after treatment were performed using mass spectrometry combined with ultra-performance liquid chromatography (UPLC-MS). RESULTS: Compared to the placebo group, children receiving pidotimod, alone or combined with bifidobacteria, had a significantly higher proportion of symptom-free days (p=0.02 and p=0.003, respectively) and a significantly lower percentage of days with common cold (p=0.004 and p=0.005, respectively). In those children, we also found relevant changes in the urine metabolomic profile compared to children receiving placebo. Furthermore, children treated with pidotimod alone showed a different metabolic profile compared to children treated with pidotimod plus bifidobacteria. On the other side, children receiving bifidobacteria alone did not show differences with respect to the placebo group in clinical outcomes or metabolomic profiles. CONCLUSIONS: this study shows that children with RRI treated with pidotimod have a better clinical outcome and a different metabolomics profile after treatment, compared to subject receiving placebo while patients treated only with bifidobacteria did not show any difference in clinical outcomes and metabolomic profile in comparison to the placebo group. The combined treatment (pidotimod plus bifidobacterium) did not modify the clinical outcome, but metabolomic analysis was able to reveal, going beyond the clinic, a different behavior for these two groups, suggesting a possible role for the microbiota composition in the underlying physiopathologic mechanism

Ottica dell'Oftalmoscopio diretto

Lo scopo della tesi è quello di analizzare l’ottica dell’oftalmoscopio diretto, prendendo in considerazione anche i diversi fattori che possono compromettere la riuscita dell’esame del fondo oculare. I fattori possono essere legati allo strumento e/o all’occhio.Trovo che sia utile studiare il procedimento che sta dietro alla funzione di questo strumento, perchè capire com’è fatto permette poi di poter utilizzarlo in modo più opportuno nella pratica optometrica.ope