Optimization of the spark plasma sintering conditions for the consolidation of hydroxyapatite powders and characterization of the obtained products

A comparative investigation regarding the consolidation behavior displayed by three commercially available hydroxyapatite powders during Spark Plasma Sintering (SPS) is performed in this work. Starting powders are different in terms of purity, particle size, morphology and thermochemical stability. A completely dense product without secondary species is produced by SPS at 900 °C, when starting from highly pure powders with relatively small sized particles and grains. The resulting consolidated material, consisting of sub-micrometer sized hydroxyapatite grains, exhibits optical transparency and good mechanical properties. On the other hand, temperature levels up to 1,200 °C are needed to sinter powders with larger particles. This holds also true when relatively finer powders are used, also containing CaHPO4, are used. In both the latter cases products with coarser microstructures and/or significant amount of β-TCP, as a result of hydroxyapatite decomposition, are obtained. Optical, chemical resistance and mechanical properties of the resulting dense materials are correspondingly deteriorated

The color out of space: learning self-supervised representations for Earth Observation imagery

The recent growth in the number of satellite images fosters the development of effective deep-learning techniques for Remote Sensing (RS). However, their full potential is untapped due to the lack of large annotated datasets. Such a problem is usually countered by fine-tuning a feature extractor that is previously trained on the ImageNet dataset. Unfortunately, the domain of natural images differs from the RS one, which hinders the final performance. In this work, we propose to learn meaningful representations from satellite imagery, leveraging its high-dimensionality spectral bands to reconstruct the visible colors. We conduct experiments on land cover classification (BigEarthNet) and West Nile Virus detection, showing that colorization is a solid pretext task for training a feature extractor. Furthermore, we qualitatively observe that guesses based on natural images and colorization rely on different parts of the input. This paves the way to an ensemble model that eventually outperforms both the above-mentioned techniques

Health-related quality of life in patients with primary open-angle glaucoma. An italian multicentre observational study

PurposeAs a progressive condition, glaucoma may impair health-related quality of life (HRQoL), due to vision loss and other factors. This study evaluated HRQoL in a cohort of patients treated for primary open-angle glaucoma (POAG) and assessed its association with clinical features. MethodsThis was an Italian, multicentre, cross-sectional, observational study with the subgroup of newly diagnosed patients with POAG prospectively followed up for one year. Patients with previous or new diagnosis (or strong clinical suspicion) of POAG aged >18years were considered eligible. Information was collected on demographic characteristics, medical history, clinical presentation and POAG treatments. HRQoL was measured using the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) and Glaucoma Symptom Scale (GSS). Subscale and total scores were obtained and a Pearson correlation coefficient between instruments' scores calculated. ResultsA total of 3227 patients were enrolled from 2012 to 2013 and 3169 were analysed. Mean age was 66.9years. A total of 93.8% had a previous diagnosis (median duration: 8.0years). Median values for mean deviation and pattern standard deviation were 3.9 and 3.6 dB, respectively. Mean scores on most subscales of the NEI-VFQ-25 exceeded 75.0 and mean GSS subscale scores ranged between 70.8 and 79.7 (with a total mean score of 74.8). HRQoL scores on both scales were significantly inversely associated with POAG severity. ConclusionIn this large sample of Italians treated for POAG, disease severity was limited and HRQoL scores were high. QoL decreased with advancing disease severity. These findings confirm the role of vision loss in impairing QoL in POAG, underlying the importance of timely detection and appropriate treatment

Practice patterns and 90-day treatment-related morbidity in early-stage cervical cancer

To evaluate the impact of the Laparoscopic Approach to Cervical Cancer (LACC) Trial on patterns of care and surgery-related morbidity in early-stage cervical cancer

Acute Delta Hepatitis in Italy spanning three decades (1991–2019): Evidence for the effectiveness of the hepatitis B vaccination campaign

Updated incidence data of acute Delta virus hepatitis (HDV) are lacking worldwide. Our aim was to evaluate incidence of and risk factors for acute HDV in Italy after the introduction of the compulsory vaccination against hepatitis B virus (HBV) in 1991. Data were obtained from the National Surveillance System of acute viral hepatitis (SEIEVA). Independent predictors of HDV were assessed by logistic-regression analysis. The incidence of acute HDV per 1-million population declined from 3.2 cases in 1987 to 0.04 in 2019, parallel to that of acute HBV per 100,000 from 10.0 to 0.39 cases during the same period. The median age of cases increased from 27 years in the decade 1991-1999 to 44 years in the decade 2010-2019 (p < .001). Over the same period, the male/female ratio decreased from 3.8 to 2.1, the proportion of coinfections increased from 55% to 75% (p = .003) and that of HBsAg positive acute hepatitis tested for by IgM anti-HDV linearly decreased from 50.1% to 34.1% (p < .001). People born abroad accounted for 24.6% of cases in 2004-2010 and 32.1% in 2011-2019. In the period 2010-2019, risky sexual behaviour (O.R. 4.2; 95%CI: 1.4-12.8) was the sole independent predictor of acute HDV; conversely intravenous drug use was no longer associated (O.R. 1.25; 95%CI: 0.15-10.22) with this. In conclusion, HBV vaccination was an effective measure to control acute HDV. Intravenous drug use is no longer an efficient mode of HDV spread. Testing for IgM-anti HDV is a grey area requiring alert. Acute HDV in foreigners should be monitored in the years to come

Association of Variants in the SPTLC1 Gene With Juvenile Amyotrophic Lateral Sclerosis

Importance: Juvenile amyotrophic lateral sclerosis (ALS) is a rare form of ALS characterized by age of symptom onset less than 25 years and a variable presentation.Objective: To identify the genetic variants associated with juvenile ALS.Design, Setting, and Participants: In this multicenter family-based genetic study, trio whole-exome sequencing was performed to identify the disease-associated gene in a case series of unrelated patients diagnosed with juvenile ALS and severe growth retardation. The patients and their family members were enrolled at academic hospitals and a government research facility between March 1, 2016, and March 13, 2020, and were observed until October 1, 2020. Whole-exome sequencing was also performed in a series of patients with juvenile ALS. A total of 66 patients with juvenile ALS and 6258 adult patients with ALS participated in the study. Patients were selected for the study based on their diagnosis, and all eligible participants were enrolled in the study. None of the participants had a family history of neurological disorders, suggesting de novo variants as the underlying genetic mechanism.Main Outcomes and Measures: De novo variants present only in the index case and not in unaffected family members.Results: Trio whole-exome sequencing was performed in 3 patients diagnosed with juvenile ALS and their parents. An additional 63 patients with juvenile ALS and 6258 adult patients with ALS were subsequently screened for variants in the SPTLC1 gene. De novo variants in SPTLC1 (p.Ala20Ser in 2 patients and p.Ser331Tyr in 1 patient) were identified in 3 unrelated patients diagnosed with juvenile ALS and failure to thrive. A fourth variant (p.Leu39del) was identified in a patient with juvenile ALS where parental DNA was unavailable. Variants in this gene have been previously shown to be associated with autosomal-dominant hereditary sensory autonomic neuropathy, type 1A, by disrupting an essential enzyme complex in the sphingolipid synthesis pathway.Conclusions and Relevance: These data broaden the phenotype associated with SPTLC1 and suggest that patients presenting with juvenile ALS should be screened for variants in this gene.</p

Genome-wide Analyses Identify KIF5A as a Novel ALS Gene

To identify novel genes associated with ALS, we undertook two lines of investigation. We carried out a genome-wide association study comparing 20,806 ALS cases and 59,804 controls. Independently, we performed a rare variant burden analysis comparing 1,138 index familial ALS cases and 19,494 controls. Through both approaches, we identified kinesin family member 5A (KIF5A) as a novel gene associated with ALS. Interestingly, mutations predominantly in the N-terminal motor domain of KIF5A are causative for two neurodegenerative diseases: hereditary spastic paraplegia (SPG10) and Charcot-Marie-Tooth type 2 (CMT2). In contrast, ALS-associated mutations are primarily located at the C-terminal cargo-binding tail domain and patients harboring loss-of-function mutations displayed an extended survival relative to typical ALS cases. Taken together, these results broaden the phenotype spectrum resulting from mutations in KIF5A and strengthen the role of cytoskeletal defects in the pathogenesis of ALS.Peer reviewe

Spontaneous rupture of an aneurysm of the left gastroepiploic artery.

Abstract This report describes the successful surgical treatment of a ruptured aneurysm of the left gastroepiploic artery. These aneurysms represent a very small fraction of visceral aneurysms

Near Real Time Fire Detection Service via the PROBA-V Mission Exploitation Platform

In the framework of the PROBA -V Mission Exploitation Platform (PROBA-V MEP), the “Detection of fires and burned areas” research activity is part of the PROBA-V MEP Third Party Services aimed at better facilitating the exploitation of PROBA-V data across the EO open science community. Progressive Systems carried out this research activity dedicated to support the Centre de Suivi Ecologique (CSE, Senegal) participation in the Monitoring for Environment and Security in Africa (MESA) project through the development of a fire detection and burned areas characterization service over the “Economic Community of Western Africa States” (ECOWAS). The Fire Detection algorithm is based on a modified implementation of a temporal Kalman filter which is capable to detect hotspots in near real time from Meteosat Second Generation (MSG) Spinning Enhanced Visible and Infrared Imager (SEVIRI) geostationary multispectral data. The first component of the algorithm consists of a clear-air anomaly detection making use of multispectral Kalman features. After that, the second component is capable to classify identified anomalies between clouds and hotspots. The service takes in input SEVIRI multispectral data provisioned in near real time by EumetCast every 15 minutes. A direct access to PROBA-V archive of vegetation index and burned area products is then provisioned via the PROBA-V MEP infrastructure. In order to initialize the algorithm over the entire domain, a background model has been retrieved for each pixel and considered channel to depict the daily radiance trend in time of nominal clear air observations. Average values have been calculated, for each channel used by the Kalman filter, by exploiting the EUMETSAT’s Cloud Mask products to filter out anomalies from SEVIRI measurements and consider only clear-sky conditions. Main outputs of the algorithm are fire detections given in tabular and vector formats containing information such as fire ID, geolocation and confidence level together with PROBA-V derived NDVI and NDWI index estimations. Moreover the system is capable to compute a “Fire Occurrence” product over a defined composite period that complements the available PROBA-V Burnt Area product. The main code has been developed in Python while wrapper scripts have been written in BASH. The service prototype has been deployed within a Virtual Machine equipped with 4vCPUs and 8GB RAM within the PROBA-V MEP. Such resources are sufficient to guarantee the near real-time processing over the Western Africa area according to the input product delivery every 15 minutes. First investigations on clear sky classification of MSG scenes over ECOWAS region have shown a strong correlation with respect to EUMETSAT’s Cloud Mask products. Furthermore preliminary Fire Detection comparisons with respect to EUMETSAT’s FRP products has shown a fairly good agreement within hotspots having similar confidence level. Fine tuning of clear-sky and anomaly thresholds is required together with a validation of fire detections with respect to other products (e.g. MODIS FIRMS). Finally further activities, such as field validation campaign and CSE staff training, are planned to validate results and gather feedback from local stakeholders

Classical Bioglass®and innovative CaO-rich bioglass powders processed by Spark Plasma Sintering: a comparative study

Densification and crystallization phenomena taking place when a recently developed CaO-rich bioactive glass and conventional 45S5 Bioglass® are processed by Spark Plasma Sintering (SPS) are examined. Fully dense and wholly amorphous products can be obtained from the new glass composition at 730°C after 2min dwell time. Moreover, temperatures equal or higher than 830°C are needed to induce crystallization (α- and β-CaSiO3) in the parent glass. Conversely, Na6Ca3Si6O18 crystals are formed in sintered 45S5 samples produced under optimal conditions (550°C, 2min), although the glassy character is still preserved.Products resulting from the innovative glass powders generally display higher hardness and local elastic modulus. Devitrification also provides improvements in this system. In contrast, mechanical properties become slightly worsen when classical bioglass is processed at 600. °C. This can be probably associated to the corresponding decrease in compactness which, apparently, overcomes the benefits arising from the crystallization progress