190 research outputs found
Environmental sustainability of orthopedic devices produced with powder bed fusion
Additive manufacturing consists in melting metallic powders to produce objects from 3D data, layer upon layer. Its industrial applications range from automotive, biomedical (e.g., prosthetic implants for dentistry and orthopedics), aeronautics and others. This study uses life cycle assessment to evaluate the possible improvement in environmental performance of laser-based powder bed fusion additive manufacturing systems on prosthetic device production. Environmental impacts due to manufacturing, use, and end of life of the designed solution were assessed. In addition, two powder production technologies, gas atomization (GA) and plasma atomization (PA), were compared in order to establish the most sustainable one. Production via traditional subtractive technologies and the additive manufacturing production were also compared. 3D building was found to have a significant environmental advantage compared to the traditional technology. The powder production process considerably influences on a damage point of view the additive manufacturing process; however, its impact can be mitigated if GA powders are employed
Suitability of switchgrass (Panicum virgatum L.) as a forage crop in the Mediterranean area
In Mediterranean rainfed cropping systems, drought-resistant crops can increase yield and availability of forage during the summer period. In North America, switchgrass (Panicum virgatum L.) has been used for decades as pasture and fodder. In Europe, switchgrass has been investigated mainly for its potential as an energy crop. e overall aim of the present study was to analyse the suitability of switchgrass as a forage crop in a Mediterranean environment. A eld trial was carried out in Central Italy (Pisa) to evaluate the productivity and nutritive value in mature stands of two switchgrass varieties (Alamo and Blackwell). Alamo reached the maturity for hay harvest (boot stage) in August, about one-month delay with respect to Blackwell. At this stage, the biomass was 13.3 and 7.5 t ha-1 of dry matter (DM) in Alamo and Blackwell, respectively. Both varieties produced a summer regrowth harvested in autumn. Nutritive value declined during the growing season due to the increase of bre and the reduction of protein content. Saponin content signi cantly di ered between varieties and according to the growth stage, ranging from 1.8 to 4.5 mg g-1 DM. is study provides useful knowledge to favour the introduction of perennial grasses as forage crops in the Mediterranean, leading to several environmental bene ts when compared with the annual species that currently cover half of the forage cropland in Tuscany
Anthropic pressures on Nature 2000 Sites: recommendations and monitoring criteria for the pollution emergency response activities within the Orbetello lagoon
L’elevato valore naturalistico e socioeconomico
di un Sito Natura 2000 richiede che tutte le
attività antropiche che si svolgono al suo interno
(es. pesca, turismo, trasporti, attività industriali,
etc.) siano gestite in maniera tale da non pregiudicare
le specie e gli habitat per i quali l’area è
stata designata. Molti di questi Siti sono ambienti
di transizione, ovvero zone che costituiscono il
passaggio naturale tra terra e mare. La loro
posizione di interfaccia tra questi due ambienti li
rende ecosistemi unici e biologicamente molto
produttivi, sede di meccanismi di regolazione dei processi interattivi della biosfera nelle due
fasi, terrestre e marina. In alcuni Siti la presenza
di attività antropiche diffuse e prolungate nel
tempo ha portato al riscontro di stati di
contaminazione elevata, fino all’inclusione di
queste zone, o parti di esse, tra i Siti di bonifica
di Interesse Nazionale (SIN). Il presente lavoro
descrive le linee di indirizzo e le attività di
monitoraggio da attuare per la salvaguardia della
salute pubblica e dell’ambiente nel corso degli
interventi di messa in sicurezza di emergenza
predisposti nell’area lagunare antistante l’area
industriale Ex Sitoco, all’interno della perimetrazione
del SIN di Orbetello, incluso in un Sito di
Importanza Comunitaria. Le matrici ambientali
potenzialmente a rischio a causa dell’esecuzione
di tali interventi sono: acqua, sedimento,
biocenosi acquatiche, avifauna, uomo.
È altresì importante valutare gli effetti che le
ipotetiche modifiche su microscala, apportate a
livello di ogni matrice, potrebbero causare nel
lungo periodo su macroscala.The high naturalistic and socio-economic value
of Natura 2000 sites requires that all human
activities performed within their borders (e.g.
fishing, tourism, transports, industrial activities)
are regulated. Indeed, the site management
should assure the effective safeguard of all
species and habitats of European interest
included in the protected area. A lot of such
sites are located in transitional environments,
that are areas characterised by a natural
progression from the terrestrial to the water
environments. Such environments include
unique and very productive habitats, and they
represent the regulation mechanisms of the
interactive processes of the terrestrial and
marine biosphere. In some sites, the presence
of human activities that are distributed both in
space and time has led to high levels of contamination,
that in some cases even required their
inclusion in Reclamation Sites of National
Interest (SIN). The present study describes the
planning and monitoring activities to be
performed in order to safeguard human and
environment health during the actions of MISE in the lagoonal area in front of the industrial area
Ex Sitoco, within the borders of the Orbetello
SIN, included in a SCI. The environmental
parameters that are potentially at risk due to
such activities are: water, sediment, water
biocenosis, birds, humans. Furthermore, it is
important to evaluate the effects that potential
variations at the microscale level may cause at
the macroscale level
Diets supplemented with condensed and hydrolysable tannins affected rumen fatty acid profile and plasmalogen lipids, ammonia and methane production in an in vitro study
The livestock sector constitutes 14.5% of global green-house gas (GHG) emissions and soil and water pollution due to nitrogen excretion. Methane and nitrogen excretions in ruminants can be mitigated by specific feeding strategies, and tannins reduce methanogenesis and ammonia syntheses. In our study, two kinds of condensed tannins (Mimosa and Gambier) and two kinds of hydrolysable tannins (Chestnut and Tara) were added (4 g/100 g DM) to a basal feed (barley: 48 g/100 g DM, wheat bran: 23 g/100 g DM, dehydrated alfalfa hay:15 g/100 g DM, soybean meal: 10 g/100 g DM and molasses: 2 g/100 g DM), inoculated with rumen fluid and fermented for 24 h. The methane, ammonia, fatty acid and plasmalogen lipid profile were determined. The results confirmed that tannins are an important family of heterogeneous compounds whose effect on rumen metabolism is strongly linked to their different characteristics. Chestnut tannin extract was shown to be a good compromise. It improved the sustainability of ruminant rearing by decreasing methanogenesis (control feed 0.159 vs chestnut feed 0.137 mmol/L rumen fluid; p =.0326), ammonia production (control feed 248 vs chestnut feed 179 mg/L rumen fluid; p <.0001) and enhancing acetate synthesis (production rate: chestnut 68.68% vs 49.64% of control).HIGHLIGHTS Tannin extracts from trees and shrubs can be used to modulate rumen fermentation. The positive effect of chestnut tannin extract was demonstrated on methane and ammonia production. Tannins showed no protective action on C18:2 trans 11
Transposable element activation promotes neurodegeneration in a Drosophila model of Huntington's disease
Huntington's disease (HD) is an autosomal dominant disorder with progressive motor dysfunction and cognitive decline. The disease is caused by a CAG repeat expansion in the IT15 gene, which elongates a polyglutamine stretch of the HD protein, Huntingtin. No therapeutic treatments are available, and new pharmacological targets are needed. Retrotransposons are transposable elements (TEs) that represent 40% and 30% of the human and Drosophila genomes and replicate through an RNA intermediate. Mounting evidence suggests that mammalian TEs are active during neurogenesis and may be involved in diseases of the nervous system. Here we show that TE expression and mobilization are increased in a Drosophila melanogaster HD model. By inhibiting TE mobilization with Reverse Transcriptase inhibitors, polyQ-dependent eye neurodegeneration and genome instability in larval brains are rescued and fly lifespan is increased. These results suggest that TE activation may be involved in polyQ-induced neurotoxicity and a potential pharmacological target
Obstetric outcomes in pregnant COVID-19 women: the imbalance of von Willebrand factor and ADAMTS13 axis
Background: Thrombotic microangiopathy has been invoked as one of the most important mechanisms of damage in COVID-19 patients. Protease ADAMTS13 is a marker of microangiopathy responsible for controlling von Willebrand multimers size. Von Willebrand factor/ADAMTS13 ratio has been found impaired in COVID-19 patients outside pregnancy. Methods: We prospectively investigated 90 pregnant women admitted to two tertiary academic hospitals in Italy with a laboratory-confirmed diagnosis of SARS-CoV-2 infection. Demographic, clinical information and routine laboratory data were collected at the hospital admission and until discharge. We investigated whether vonWillebrand /ADAMTS13 axis imbalance is a predictor of adverse outcomes. Logistic regression analysis, which controlled for potential confounders, was performed to evaluate the association between laboratory parameters and clinical outcomes. Results: Most women (55.6%) were parae, with median gestational age at admission of 39 weeks. At hospital admission, 63.3% were asymptomatic for COVID-19 and 24.4% showed more than one sign or symptom of infection. Nulliparae with group O showed Willebrand / ADA MTS-13 ratios significantly lower than non-O, whereas in multiparae this difference was not observed. Logistic regression showed that ratio von Willebrand to ADAMTS13 was significantly and independently associated with preterm delivery (OR 1.9, 95%CI 1.1–3.5). Conclusion: This study shows an imbalance of vonWillebrand /ADAMTS13 axis in pregnant women with COVID-19, leading to a significantly higher and independent risk of preterm delivery. Monitoring these biomarkers might support decision making process to manage and follow-up pregnancies in this setting
First tests for an online treatment monitoring system with in-beam PET for proton therapy
PET imaging is a non-invasive technique for particle range verification in
proton therapy. It is based on measuring the beta+ annihilations caused by
nuclear interactions of the protons in the patient. In this work we present
measurements for proton range verification in phantoms, performed at the CNAO
particle therapy treatment center in Pavia, Italy, with our 10 x 10 cm^2 planar
PET prototype DoPET. PMMA phantoms were irradiated with mono-energetic proton
beams and clinical treatment plans, and PET data were acquired during and
shortly after proton irradiation. We created 1-D profiles of the beta+ activity
along the proton beam-axis, and evaluated the difference between the proximal
rise and the distal fall-off position of the activity distribution. A good
agreement with FLUKA Monte Carlo predictions was obtained. We also assessed the
system response when the PMMA phantom contained an air cavity. The system was
able to detect these cavities quickly after irradiation.Comment: 11 pages, 6 figures, Proceedings for International Workshop on
Radiation Imaging Detectors, 201
Treatment of Intracranial Aneurysms with Self-Expandable Braided Stents: A Systematic Review and Meta-Analysis
International audience; BACKGROUND:The safety and efficacy of treatment with self-expandable braided stents (LEO and LVIS) required further investigation.PURPOSE:Our aim was to analyze the outcomes after treatment with braided stents.DATA SOURCES:A systematic search of 3 databases was performed for studies published from 2006 to 2017.STUDY SELECTION:According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we included studies reporting patients treated with LEO or LVIS stents.DATA ANALYSIS:Random-effects meta-analysis was used to pool the following: aneurysm occlusion rate, complications, and neurologic outcomes.DATA SYNTHESIS:Thirty-five studies evaluating 1426 patients treated with braided stents were included in this meta-analysis. Successful stent delivery and complete aneurysm occlusion were 97% (1041/1095; 95% CI, 95%-98%) (I2 = 44%) and 88.3% (1097/1256; 95% CI, 85%-91%) (I2 = 72%), respectively. Overall, treatment-related complications were 7.4% (107/1317; 95% CI, 5%-9%) (I2 = 44%). Ischemic/thromboembolic events (48/1324 = 2.4%; 95% CI, 1.5%-3.4%) (I2 = 27%) and in-stent thrombosis (35/1324 = 1.5%; 95% CI, 0.6%-1.7%) (I2 = 0%) were the most common complications. Treatment-related morbidity was 1.5% (30/1324; 95% CI, 0.9%-2%) and was comparable between the LEO and LVIS groups. Complication rates between the anterior (29/322 = 8.8%; 95% CI, 3.4%-12%) (I2 = 41%) versus posterior circulation (10/84 = 10.5%; 95% CI, 4%-16%) (I2 = 0%) and distal (30/303 = 8%; 95% CI, 4.5%-12%) (I2 = 48%) versus proximal aneurysms (14/153 = 9%; 95% CI, 3%-13%) (I2 = 46%) were comparable (P > .05).LIMITATIONS:Limitations were selection and publication biases.CONCLUSIONS:In this analysis, treatment with the LEO and LVIS stents was relatively safe and effective. The most common complications were periprocedural thromboembolisms and in-stent thrombosis. The rate of complications was comparable among anterior and posterior circulation aneurysms, as well as for proximal and distally located lesions
Pneumocystis carinii pneumonia in patients with malignant haematological diseases: 10 years' experience of infection in GIMEMA centres.
A retrospective survey was conducted over a 10-year period (1990-99) among 52 haematology divisions in order to evaluate the clinical and laboratory characteristics and outcome of patients with proven Pneumocystis carinii pneumonia (PCP) complicating haematological diseases. The study included 55 patients (18 with non-Hodgkin's lymphoma, 10 with acute lymphoblastic leukaemia, eight with acute myeloid leukaemia, five with chronic myeloid leukaemia, four with chronic lymphocytic leukaemia, four with multiple myeloma, three with myelodys-plastic syndrome, two with myelofibrosis and one with thalassemia) who developed PCP. Among these, 18 (33%) underwent stem cell transplantation; only two received an oral prophylaxis with trimethroprim/sulphamethoxazole. Twelve patients (22%) developed PCP despite protective isolation in a laminar airflow room. The most frequent symptoms were: fever (86%), dyspnoea (78%), non-productive cough (71%), thoracic pain (14%) and chills (5%); a severe hypoxaemia was present in 39 patients (71%). Chest radiography or computerized tomography showed interstitial infiltrates in 34 patients (62%), alveolar infiltrates in 12 patients (22%), and alveolar-interstitial infiltrates in nine patients (16%). Bronchoalveolar lavage was diagnostic in 47/48 patients, induced sputum in 9/18 patients and lung biopsy in 3/8 patients. The diagnosis was made in two patients at autopsy. All patients except one started a specific treatment (52 patients trimethroprim/sulphamethoxazole, one pentamidine and one dapsone). Sixteen patients (29%) died of PCP within 30 d of diagnosis. Multivariate analysis showed that prolonged steroid treatment (P < 0.006) and a radiological picture of diffuse lung involvement (P < 0.003) were negative diagnostic factors
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