Three-dimension-printed custom-made prosthetic reconstructions: from revision surgery to oncologic reconstructions

Background The use of custom-made 3D-printed prostheses for reconstruction of severe bone defects in selected cases is increasing. The aims of this study were to evaluate (1) the feasibility of surgical reconstruction with these prostheses in oncologic and non-oncologic settings and (2) the functional results, complications, and outcomes at short-term follow-up. Methods We analyzed 13 prospectively collected patients treated between June 2016 and January 2018. Diagnoses were primary bone tumour (7 patients), metastasis (3 patients), and revision of total hip arthroplasty (3 patients). Pelvis was the most frequent site of reconstruction (7 cases). Functional results were assessed with MSTS score and complications according to Henderson et al. Statistical analysis was performed using Kaplan-Meier and log-rank test curves. Results At a mean follow-up of 13.7 months (range, 6 \u2013 26 months), all patients except one were alive. Oncologic outcomes show seven patients NED (no evidence of disease), one NED after treatment of metastasis, one patient died of disease, and another one was alive with disease. Overall survival was 100% and 80% at one and two years, respectively. Seven complications occurred in five patients (38.5%). Survival to all complications was 62% at two years of follow-up. Functional outcome was good or excellent in all cases with a mean score of 80.3%. Conclusion 3D-printed custom-made prostheses represent a promising reconstructive technique in musculoskeletal oncology and challenging revision surgery. Preliminary results were satisfactory. Further studies are needed to evaluate prosthetic design, fixation methods, and stability of the implants at long-ter

Evidence for reduced magnetic braking in polars from binary population models

We present the first population synthesis of synchronous magnetic cataclysmic variables, called polars, taking into account the effect of the white dwarf (WD) magnetic field on angular momentum loss. We implemented the reduced magnetic braking (MB) model proposed by Li, Wu & Wickramasinghe into the Binary Stellar Evolution (BSE) code recently calibrated for cataclysmic variable (CV) evolution. We then compared separately our predictions for polars and non-magnetic CVs with a large and homogeneous sample of observed CVs from the Sloan Digital Sky Survey. We found that the predicted orbital period distributions and space densities agree with the observations if period bouncers are excluded. For polars, we also find agreement between predicted and observed mass transfer rates, while the mass transfer rates of non-magnetic CVs with periods ≳3 h drastically disagree with those derived from observations. Our results provide strong evidence that the reduced MB model for the evolution of highly magnetized accreting WDs can explain the observed properties of polars. The remaining main issues in our understanding of CV evolution are the origin of the large number of highly magnetic WDs, the large scatter of the observed mass transfer rates for non-magnetic systems with periods ≳3 h, and the absence of period bouncers in observed samples

Structure of the accretion flow of IX Velorum as revealed by high-resolution spectroscopy

Context: Several high-mass transfer cataclysmic variables show evidence for outflow from the system, which could play an important role in their evolution. We investigate the system IX Vel, which was proposed to show similar characteristics. Aims: We study the structure of the IX Vel system, particularly the structure of its accretion flow and accretion disc. Methods: We use high-resolution time-resolved spectroscopy to construct radial velocity curves of the components in IX Vel, we compute Doppler maps of the system which we use to estimate the temperature distribution maps. Results: We improve the spectroscopic ephemeris of the system and its orbital period P_orb = 0.19392793(3) d. We construct Doppler maps of the system based on hydrogen and helium emission lines and the Bowen blend. The maps show features corresponding to the irradiated face of the secondary star, the outer rim of the accretion disc, and low-velocity components located outside the accretion disc and reaching towards L3. We constructed a temperature distribution map of the system using the Doppler maps of Balmer lines. Apart from the features found in the Doppler maps, the temperature distribution map shows a region of high temperature in the accretion disc connecting the expected position of a bright spot and the inner parts of the disc. Conclusions: We interpret the low-velocity emission found in the Doppler map as emission originating in the accretion disc wind and in an outflow region located in the vicinity of the third Lagrangian point L3. This makes IX Vel a member of the RW Sex class of Cataclysmic Variables

Addressing class imbalance in deep learning for acoustic target classification

Acoustic surveys provide important data for fisheries management. During the surveys, ship-mounted echo sounders send acoustic signals into the water and measure the strength of the reflection, so-called backscatter. Acoustic target classification (ATC) aims to identify backscatter signals by categorizing them into specific groups, e.g. sandeel, mackerel, and background (as bottom and plankton). Convolutional neural networks typically perform well for ATC but fail in cases where the background class is similar to the foreground class. In this study, we discuss how to address the challenge of class imbalance in the sampling of training and validation data for deep convolutional neural networks. The proposed strategy seeks to equally sample areas containing all different classes while prioritizing background data that have similar characteristics to the foreground class. We investigate the performance of the proposed sampling methodology for ATC using a previously published deep convolutional neural network architecture on sandeel data. Our results demonstrate that utilizing this approach enables accurate target classification even when dealing with imbalanced data. This is particularly relevant for pixel-wise semantic segmentation tasks conducted on extensive datasets. The proposed methodology utilizes state-of-the-art deep learning techniques and ensures a systematic approach to data balancing, avoiding ad hoc methods.Addressing class imbalance in deep learning for acoustic target classificationpublishedVersio

Searching for novel carbonic anhydrase inhibitors: from virtual screening to the lab bench

Carbonic Anhydrases (CAs) are zinc metalloenzymes that catalyze the reversible hydration of carbon dioxide to bicarbonate both in prokaryotes and eukaryotes. In this context, Computer Aided Drug Design strategies have emerged as powerful tools in the modern drug discovery paradigm. In particular, using ligand- and pharmacophore-based virtual screening approaches, we identified novel chemical entities with original chemotypes, that showed an interesting and selective inhibitory activity in nanomolar/low micromolar range toward CA I and CAII, isoforms. Herein, we present the hit-to-lead optimization process for these prototypes

The evolution of cataclysmic variables

Cataclysmic variables (CVs) are short–period (' 80 min to ' day) binaries in which a white dwarf accretes from a low–mass companion. Since both stellar components are structurally simple and there is a sufficiently large number of relatively bright CVs known, it is possible to carry out detailed observational population studies. Therefore CVs are one of the best–suited classes to test, constrain, and further develop our understanding of the evolution of all interacting compact binaries, such as black hole binaries, X-ray transients, milli–second pulsars and, more importantly, Type Ia Supernova (SN Ia), our yardsticks for measuring distances on cosmological distance scales. In this thesis, I present the study of a large sample of CV white dwarfs. Their effective temperatures are determined from the analysis of their ultraviolet Hubble Space Telescope (HST ) spectra and provide a test for the current models of CV evolution. Our results highlight the presence of a number of discrepancies between current population models and observations, particularly the lack of period bounce systems, i.e. highly evolved CVs with brown dwarf companions, which are predicted to make up for ' 40 . 70 % of the present day Galactic CV population. The combination of the HST data with optical phase–resolved X–shooter observations is a powerful tool to identify period bouncers. We study the spectral energy distribution of QZ Lib, in which we identify the coolest white dwarf at the longest orbital period below the period gap and we spectroscopically confirm the presence of a brown dwarf donor. These characteristics make QZ Lib the strongest period bouncer candidate identified so far. Although successful, this method requires the use of expensive space–based and large ground–based facilities, indicating the need for a more efficient observing strategy. We present here CHiCaS, the Compact binary HIgh CAdence Survey which represents the first systematic attempt to identify, via the detection of their eclipses, the elusive population of period bouncers. By the end of next year, this program will deliver one minute cadence lightcurves for ' 2:5 million objects as faint as g ' 21:5, along with full colour information. CHiCaS will also provide a complete and unbiased view into the short term variability of thousands of binaries, eclipsing systems, pulsating stars and CVs in the period gap. In our HST sample, we identify another remarkable CV: SDSS J123813.73–033932.9. Its lightcurve shows sudden increases in brightness, up to ' 0:45 mag, occurring quasi–periodically every 8–12 hours (the “brightenings”) and a nearly sinusoidal variation at half the orbital period (the “double–humps”). The HST observations show that these phenomena arise from the heating and cooling of a fraction of the white dwarf, which we conclude being caused by a modulation in the accretion rate owing to spiral density waves and thermal instabilities in the accretion disc

Disseny, construcció i avaluació d'una xarxa mesh wireless gestionada per software (SDW)

[ENGLISH] Software Defined Wireless Backhaul for Small Cells (SESAME), our project, pretends to give an answer to mobile network saturation through the introduction of dense networks formed by software-controlled small cells to address the forecasted exponential traffic increase in future Mobile networks. Using small cells we increase capacity by means of reducing cell size and densifying access networks. However, a massive deployment of this technology poses significant technical hurdles to current network architectures. In particular, backhauling outdoor Small Cells, which may be mounted on lamp posts or street furniture, is a challenging problem that needs to be addressed with efficient wireless technologies. The main goal is to improve the quality of service offered to the users through the use of SDN technology. We developed a custom forwarding algorithm which allows us the management of the routing of a wireless backhaul network in function of the radio link conditions. In order to implement this control effectively, the controller must be aware of radio conditions. We demonstrate our architecture in two different testbed prototypes, where we analyze the costs incurred in the additional processing and the centralization of state imposed by SDN, while motivating the benefits of our architecture in terms of improved network management and control. In order to build our environment we used the following technologies: Open vSwitch to manage the nodes -switchs - in the network controlled by OpenDaylight. The protocol used to exchange the messages is Openflow. Our solution has been simulated under a Linux environment due to the flexibility that it provides in terms of hardware implementation. We have emulated a wireless network in order to develop our architecture and perform appropriate tests to verify its performance in comparison with the mesh extension of 802.11 protocol.[CATALÀ] Software Defined Wireless Backhaul for Small Cells(SESAME), el nostre projecte, pretén donar resposta a la imminent saturació de les xarxes mòbils a través de la introducció de xarxes denses formades per small cells controlades per software, que permetrien assumir el creixent tràfic de dades. Fent ús de les small cells, incrementem la capacitat reduint la mida de la cel·la i densificant les xarxes d’accés. No obstant, un desplegament massiu de small cells planteja obstacles tècnics importants a les arquitectures de xarxa actuals. En concret, "backhauling outdoor small cells" que poden ésser muntats en fanals o mobiliari ì urbà, és un problema difícil que ha de ser abordat amb tecnologies wireless eficients. Per tant, el propòsit és dissenyar, implementar i avaluar un sistema que permeti a un controlador de SDN (Software Defined Network) controlar el pla d'encaminament en una xarxa Wireless que esta connectada a una xarxa cablejada –o core- per diferents punts físics (Wireless Backhaul Network). L'objectiu principal és la millora de la qualitat de servei oferta als usuaris mitjançant l’ús de la tecnologia SDN. S'introdueix la funcionalitat d'un algorisme d'encaminament propi, que permet la gestió de les rutes de sortida d'una xarxa wireless backhaul, en funció de les condicions dels enllaços radio. Per tal d'implementar aquest control de manera efectiva, cal que el controlador sigui conscient d'aquestes condicions. Demostrarem la nostra arquitectura en dos entorns de proves diferents, on analitzarem els costos implicats en el processat addicional i la centralització imposada per l'SDN, mentre motivem els beneficis de la nostra arquitectura en termes de millora de la gestió i control de la xarxa. Per tal de construir el nostre entorn, hem utilitzat: Open vSwitch per poder gestionar els nodes –switch-, mitjançant el controlador OpenDaylight. El protocol utilitzat per a l'intercanvi de missatges és OpenFlow. La solució proposada s'ha simulat sota un entorn Linux degut a la flexibilitat que ens proporciona en quant a l’ús del hardware. S'ha emulat una xarxa wireless per tal de poder desenvolupar la nostra arquitectura i així, realitzar les proves [CATALÀ] pertinents per a verificar el seu rendiment en comparació amb l’extensió mesh del protocol 802.1

The cataclysmic variable QZ Lib : a period bouncer

While highly evolved cataclysmic variables (CVs) with brown dwarf donors, often called “period bouncers”, are predicted to make up ≃ 40 − 70% of the Galactic CV population, only a handful of such systems are currently known. The identification and characterization of additional period bouncers is therefore important to probe this poorly understood phase of CV evolution. We investigate the evolution of the CV QZ Lib following its 2004 super–outburst using multi–epoch spectroscopy. From time– resolved spectroscopic observations we measure the orbital period of the system, Porb = 0.06436(20) d, which, combined with the superhump period PSH = 0.064602(24) d, yields the system mass ratio, q = 0.040(9). From the analysis of the spectral energy distribution we determine the structure of the accretion disc and the white dwarf effective temperature, Teff = 10 500 ± 1500 K. We also derive an upper limit on the effective temperature of the secondary, Teff < 1700 K, corresponding to a brown dwarf of T spectral type. The low temperature of the white dwarf, the small mass ratio and the fact that the donor is not dominating the near–infrared emission are all clues of a post bounce system. Although it is possible that QZ Lib could have formed as a white dwarf plus a brown dwarf binary, binary population synthesis studies clearly suggest this scenario to be less likely than a period bouncer detection and we conclude that QZ Lib is a CV that has already evolved through the period minimum

The Multifaceted Origin of Taurine Cattle Reflected by the Mitochondrial Genome

A Neolithic domestication of taurine cattle in the Fertile Crescent from local aurochsen (Bos primigenius) is generally accepted, but a genetic contribution from European aurochsen has been proposed. Here we performed a survey of a large number of taurine cattle mitochondrial DNA (mtDNA) control regions from numerous European breeds confirming the overall clustering within haplogroups (T1, T2 and T3) of Near Eastern ancestry, but also identifying eight mtDNAs (1.3%) that did not fit in haplogroup T. Sequencing of the entire mitochondrial genome showed that four mtDNAs formed a novel branch (haplogroup R) which, after the deep bifurcation that gave rise to the taurine and zebuine lineages, constitutes the earliest known split in the mtDNA phylogeny of B. primigenius. The remaining four mtDNAs were members of the recently discovered haplogroup Q. Phylogeographic data indicate that R mtDNAs were derived from female European aurochsen, possibly in the Italian Peninsula, and sporadically included in domestic herds. In contrast, the available data suggest that Q mtDNAs and T subclades were involved in the same Neolithic event of domestication in the Near East. Thus, the existence of novel (and rare) taurine haplogroups highlights a multifaceted genetic legacy from distinct B. primigenius populations. Taking into account that the maternally transmitted mtDNA tends to underestimate the extent of gene flow from European aurochsen, the detection of the R mtDNAs in autochthonous breeds, some of which are endangered, identifies an unexpected reservoir of genetic variation that should be carefully preserved