1,024 research outputs found
Relativistic plasmas in AGN jets - From synchrotron radiation to -ray emission
Relativistic jets of plasma are a key ingredient of many types of Active
Galactic Nuclei (AGN). Today we know that AGNs are powered by the accretion of
inter stellar material into the gravitational field of a Super Massive Black
Hole and that this process can release as much power as a whole galaxy, like
the Milky Way, from a region that is comparable to the Solar System in size.
Depending on the properties of the central energy source, a large fraction of
this power can be involved in the acceleration of magnetized plasmas at
relativistic speeds, to form large scale jets. The presence of jets affects the
spectrum of AGNs through the emission of synchrotron radiation and Inverse
Compton scattering of low energy photons, thus leading to a prominent
non-thermal spectrum, some times extending from radio frequencies all the way
up to -ray energies. Here we review some characteristic processes of
radiation emission in AGN jets, which lead to the emission of photons in the
radio, optical, X-ray and -ray bands, and we present the results of a
spectroscopic campaign of optical counterparts. We discuss our observations and
their connection with -ray properties in a scenario that traces the
role of relativistic jets in different classes of AGNs, detected both in the
local as well as in the remote Universe.Comment: 11 pages, 5 figures (3 in color), proceedings of the XXVIII School on
Physics of Ionized Gases (SPIG), accepted for publication on the European
Journal of Physics
A European map of living forest biomass and carbon stock - Executive report
Forest ecosystems have a key role in the global carbon cycle and are considered large and persistent carbon sinks. The CO2 fixed by photosynthesis is one of the most important components of the carbon cycle, and forests play a determinant role in this process. Therefore, spatially explicit data and assessments of forest biomass and carbon is of paramount importance for the design and implementation of effective sustainable forest management options and forest related policies at the European level.
The aim of this report is to present a summary of early results of the FOREST Action activities on forest biomass and carbon stock in Europe. In this report we present European-wide maps of forest biomass and carbon stock at IPCC Tier 1 level. Maps of forest biomass and carbon stock are relevant for quantifying terrestrial carbon storage and carbon sinks as well as for estimating potential emissions from land cover changes (afforestation, deforestation, reforestation), forest fragmentation and biotic (pests) and abiotic (e.g. forest fires, windstorms) disturbances. We describe the input data and approach, then present a summary examining the potential of the approach and further work as well as data needs in this field.
The maps presented, implemented following the IPCC methodology, represent spatially explicit biomass and carbon stock on forested land disaggregated at 1 km x 1 km grid cells. The resulting maps represent the biomass and carbon at continental level, accounting for around 90% of the total continental amounts of biomass and carbon reported in the FAOâs Global Forest Resource Assessment (FRA) and State of Europeâs Forest report from the Ministerial Conference on the Protection of Forest in Europe (MCPFE). To account for regional discrepancies the maps were then adjusted to match FRA amounts of biomass and carbon at the country level. This report will be followed by an extended report including methodological details of the approach implemented.JRC.H.3-Forest Resources and Climat
Knotless "three-U-stitches" technique for urethrovesical anastomosis during laparoscopic radical prostatectomy
We describe a new technique for urethrovesical anastomosis that consists
of placing three âUâ stitches of Monocryl 2-0 to connect the bladder neck and urethral
stump together. The margins are united by a double passage of the suture, without tying
any knots. The sutures are tied on the bladderâs surface using Lapra-Ty clips fixed at a
certain distance from where to two mucosal margins have been joined. We carried out
this technique on 90 patients who underwent laparoscopic extraperitoneal radical prostatectomy.
The good joining of the margins, the absence of knots and the minimum
trauma to the urethral wall together enable to create an anastomosis that is both
âsealedâ and âtension freeâ, allowing a quick âweldingâ of the margins and an early
catheter removal. Regarding urinary continence, 56.6% (51) of patientswere continent at
catheter removal, 87.6% (78) were continent 3 months later and 98.9% (89) were continent
after 6 months. In nine patients (10%), an episode of acute urinary retention
occurred within 24 h after the removal of the catheter. We did not encounter any cases
of vesicourethral anastomosis stenosis
Modeling Gross Primary Production of Agro-Forestry Ecosystems by Assimilation of Satellite-Derived Information in a Process-Based Model
In this paper we present results obtained in the framework of a regional-scale analysis of the carbon budget of poplar plantations in Northern Italy. We explored the ability of the process-based model BIOME-BGC to estimate the gross primary production (GPP) using an inverse modeling approach exploiting eddy covariance and satellite data. We firstly present a version of BIOME-BGC coupled with the radiative transfer models PROSPECT and SAILH (named PROSAILH-BGC) with the aims of i) improving the BIOME-BGC description of the radiative transfer regime within the canopy and ii) allowing the assimilation of remotely-sensed vegetation index time series, such as MODIS NDVI, into the model. Secondly, we present a two-step model inversion for optimization of model parameters. In the first step, some key ecophysiological parameters were optimized against data collected by an eddy covariance flux tower. In the second step, important information about phenological dates and about standing biomass were optimized against MODIS NDVI. Results obtained showed that the PROSAILH-BGC allowed simulation of MODIS NDVI with good accuracy and that we described better the canopy radiation regime. The inverse modeling approach was demonstrated to be useful for the optimization of ecophysiological model parameters, phenological dates and parameters related to the standing biomass, allowing good accuracy of daily and annual GPP predictions. In summary, this study showed that assimilation of eddy covariance and remote sensing data in a process model may provide important information for modeling gross primary production at regional scale
Near-optimal experimental design for model selection in systems biology
Motivation:âBiological systems are understood through iterations of modeling and experimentation. Not all experiments, however, are equally valuable for predictive modeling. This study introduces an efficient method for experimental design aimed at selecting dynamical models from data. Motivated by biological applications, the method enables the design of crucial experiments: it determines a highly informative selection of measurement readouts and time points. Results:âWe demonstrate formal guarantees of design efficiency on the basis of previous results. By reducing our task to the setting of graphical models, we prove that the method finds a near-optimal design selection with a polynomial number of evaluations. Moreover, the method exhibits the best polynomial-complexity constant approximation factor, unless P = NP. We measure the performance of the method in comparison with established alternatives, such as ensemble non-centrality, on example models of different complexity. Efficient design accelerates the loop between modeling and experimentation: it enables the inference of complex mechanisms, such as those controlling central metabolic operation. Availability:âToolbox âNearOED' available with source code under GPL on the Machine Learning Open Source Software Web site (mloss.org). Contact:â[email protected] Supplementary information:âSupplementary data are available at Bioinformatics onlin
Comparison of the clinical usefulness of different urinary tests for the initial detection of bladder cancer: a systematic review
Objectives: The standard initial approach in patients with hematuria or other symptoms suggestive of bladder cancer (BC) is a combination of cystoscopy and urine cytology (UC); however, UC has low sensitivity particularly in low-grade tumors. The aim of the present review was to critically analyze and compare results in the literature of promising molecular urinary tests for the initial diagnosis of BC. Methods: We searched in the Medline and Cochrane Library databases for literature from January 2009 to January 2019, following the PRISMAguidelines. Results: In terms of sensitivity, ImmunoCyt showed the highest mean and median value, higher than UC. All tests analyses showed higher mean and median sensitivity when compared with UC. In terms of specificity, only UroVysion and Microsatellite analyses showed mean and median values similar to those of UC, whereas for all other tests, the specificity was lower than UC. It is evident that the sensitivity of UC is particularly low in low grade BC. Urinary tests mainly had improved sensitivity when compared to UC, and ImmunoCyt and UroVysion had the highest improvement in low grade tumors. Conclusions: Most of the proposed molecular markers were able to improve the sensitivity with similar or lower specificity when compared to UC. However, variability of results among the different studies was strong. Thus, as of now, none of these markers presented evidences so as to be accepted by international guidelines for diagnosis of BC
Mitofusin-2 Down-Regulation Predicts Progression of Non-Muscle Invasive Bladder Cancer
Identification of markers predicting disease outcome is a major clinical issue for non-muscle invasive bladder cancer (NMIBC). The present study aimed to determine the role of the mitochondrial proteins Mitofusin-2 (Mfn2) and caseinolytic protease P (ClpP) in predicting the outcome of NMIBC. The study population consisted of patients scheduled for transurethral resection of bladder tumor upon the clinical diagnosis of bladder cancer (BC). Samples of the main bladder tumor and healthy-looking bladder wall from patients classified as NMIBC were tested for Mfn2 and ClpP. The expression levels of these proteins were correlated to disease recurrence, progression. Mfn2 and ClpP expression levels were significantly higher in lesional than in non-lesional tissue. Low-risk NMIBC had significantly higher Mfn2 expression levels and significantly lower ClpP expression levels than high-risk NMIBC; there were no differences in non-lesional levels of the two proteins. Lesional Mfn2 expression levels were significantly lower in patients who progressed whereas ClpP levels had no impact on any survival outcome. Multivariable analysis adjusting for the EORTC scores showed that Mfn2 downregulation was significantly associated with disease progression. In conclusion, Mfn2 and ClpP proteins were found to be overexpressed in BC as compared to non-lesional bladder tissue and Mfn2 expression predicted disease progression
SICOB-endorsed national Delphi consensus on obesity treatment optimization: focus on diagnosis, pre-operative management, and weight regain/insufficient weight loss approach
Purpose: Overweight and obesity affects 60% of adults causing more than 1.2 million deaths across world every year. Fight against involved different specialist figures and multiple are the approved weapons. Aim of the present survey endorsed by the Italian Society of Bariatric Surgery (SICOB) is to reach a national consensus on obesity treatment optimization through a Delphi process. Methods: Eleven key opinion leaders (KOLs) identified 22 statements with a major need of clarification and debate. The explored pathways were: (1) Management of patient candidate to bariatric/metabolic surgery (BMS); (2) Management of patient not eligible for BMS; (3) Management of patient with short-term (2 years) weight regain (WR) or insufficient weight loss (IWL); (4) Management of the patient with medium-term (5 years) WR; and (5) Association between drugs and BMS as WR prevention. The questionnaire was distributed to 65 national experts via an online platform with anonymized results. Results: 54 out of 65 invited panelists (83%) respond. Positive consensus was reached for 18/22 statements (82%); while, negative consensus (s20.4; s21.5) and no consensus (s11.5, s17) were reached for 2 statements, respectively (9%). Conclusion: The Delphi results underline the importance of first-line interdisciplinary management, with large pre-treatment examination, and establish a common opinion on how to properly manage post-operative IWL/WR. Level of evidence v: Report of expert committees
Cribriform pattern does not have a significant impact in Gleason Score â„7/ISUP Grade â„2 prostate cancers submitted to radical prostatectomy
The aim of this study was to correlate cribriform pattern (CP) with other parameters in a large prospective series of Gleason score â„7/ISUP grade â„2 prostate cancer (PC) cases undergoing radical prostatectomy (RP)
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