25 research outputs found

    Development of a Sentinel-2 burned area algorithm: Generation of a small fire database for sub-Saharan Africa

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    A locally-adapted multitemporal two-phase burned area (BA) algorithm has been developed using as inputs Sentinel-2 MSI reflectance measurements in the short and near infrared wavebands plus the active fires detected by Terra and Aqua MODIS sensors. An initial burned area map is created in the first step, from which tile dependent statistics are extracted for the second step. The whole Sub-Saharan Africa (around 25 M km(2)) was processed with this algorithm at a spatial resolution of 20 m, from January to December 2016. This period covers two half fire seasons on the Northern Hemisphere and an entire fire season in the South. The area was selected as existing BA products account it to include around 70% of global BA. Validation of this product was based on a two-stage stratified random sampling of Landsat multitemporal images. Higher accuracy values than existing global BA products were observed, with Dice coefficient of 77% and omission and commission errors of 26.5% and 19.3% respectively. The standard NASA BA product (MCD64A1 c6) showed a similar commission error (20.4%), but much higher omission errors (59.6%), with a lower Dice coefficient (53.6%). The BA algorithm was processed over > 11,000 Sentinel-2 images to create a database that would also include small fires (< 100 ha). This is the first time a continental BA product is generated from medium resolution sensors (spatial resolution = 20 m), showing their operational potential for improving our current understanding of global fire impacts. Total BA estimated from our product was 4.9 M km(2), around 80% larger area than what the NASA BA product (MCD64A1 c6) detected in the same period (2.7 M km(2)). The main differences between the two products were found in regions where small fires (< 100 ha) account for a significant proportion of total BA, as global products based on coarse pixel sizes (500 m for MCD64A1) unlikely detect them. On the negative side, Sentinel-2 based products have lower temporal resolution and consequently are more affected by cloud/cloud shadows and have less temporal reporting accuracy than global BA products. The product derived from S2 imagery would greatly contribute to better understanding the impacts of small fires in global fire regimes, particularly in tropical regions, where such fires are frequent. This product is named FireCCISFD11 and it is publicly available at: https://www.esa-fire-cci.org/node/262, last accessed on November 2018.This research was carried out within the Fire_cci project (https://www.esa-fire-cci.org/, last accessed on November 2018), contract no. 4000115006/15/I-NB, which has been funded by the European Space Agency (ESA) under the Climate Change Initiative Programme. The FireCCISFD11 product can be downloaded at https://www.esa-fire-cci.org/node/262 (last accessed on November 2018)

    Impact Of Sentinel Lymph Node Biopsy In Breast Cancer Patients Treated With Neoadjuvant Chemotherapy

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    EPS 196 Aim/Introduction: To analyze how many of the patients undergoing neoadjuvant chemotherapy (NCT) may benefit from SLNB, as well as the impact on patient management, especially in those with early axillary involvement. Materials and Methods: We included patients with breast carcinoma candidates to NCT discussed at the Tumor Committee of our hospital (April/2017-August/2019). All of them were subjected to clinical assessment, ultrasound and, if appropriate, histological analysis, axillary pre and post- NCT. Sentinel lymph node detection was performed after periareolar injection of [99mTc]Tc-nanocoloid (74 MBq) the day before surgery. In some cases, blue dye was injected and/or a pre-NPC metal clip was placed in the affected node. Results: Sixty-two patients were included. NCT achieved a complete breast response in 12 patients, partial in 46 and non-response in 4. Initially, 31 patients were classified as N0 and 31 as N+ (28 N1 and 3 N2), achieving a complete axillary response in 58% of N+ (18). SLNB was performed in 49 patients (79%; 100% in N0 and 58% in N+ from baseline). The gamma detection rate of the sentinel lymph node was 91.8% (93.5% in N0 and 88.9% in N+). 28 lymphadenectomies were undergone (45.2%; 22.5% in N0 and 67.7% in N+), 11 due to positive SLNB (5 N0 and 6 N1), 13 owing to lack of axillary response and 4 caused by the non-localization of the sentinel lymph node. SLNB was performed in 58% of N+ patients, of which 44.4% were negative, avoiding lymphadenectomy. Metal clip and/or blue dye techniques were used in 31 cases (50%). Conclusion: SLNB is viable in a high percentage of patients with previous NCT, with a high detection rate, even in patients with early affected axilla, avoiding lymphadenectomy to patients who achieve a complete response of the axillary lymph node

    The Importance Of Monoclonal Proteins Determination For The Correct Diagnosis Of Transthyretin Cardiac Amyloidosis By [Tc-99m]Tc-diphosphonates

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    EPS-066 Aim/Introduction: To analyze the influence of the determination of free monoclonal proteins in blood and urine in the final diagnosis of Transthyretin Cardiac Amyloidosis (TTRA). Materials and Methods: We have analyzed 200 [99mTc]Tc-diphosphonates scans: 192 performed on 190 patients under suspicion of TTRA and 7 patients with grade II-III radiotracer myocardial deposit as a casual finding (November/2013 - January/2020). Likewise, clinical and laboratory characteristics (heart failure, LVEF, proBNP levels, immunofixation in serum and/or urine for the detection of monoclonal chains and chronic renal failure) have been evaluated. A positive case has been considered for TTRAwt or senile (Score Perugini II-III scan, negative immunofixation in serum and/or urine, negative genetic study), positive case for hereditary TTRA (Score Perugini II-III scan, negative immunofixation and positive genetic study), positive case for secondary amyloidosis (positive immunofixation and presence of hematologic malignancy) and undetermined amyloidosis (immunofixation not performed or positive and absence of haematologic malignancies at follow-up). Results: 59 positive scans have been detected, 47 men (79’7%) and 12 women (20’3%). The mean age of the group of positives was 82’66 years, while that of the negatives was 72’15. The mean proBNP levels in the positives are 7561, compared to 5869 in the negative group. Immunofixation (serum and/or urine for detection of kappa or lambda monoclonal chains at 30 (50.8%) has been performed on these patients. Finally, 37.2% (22/59) resulted in ATTRwt, 3.4% (2/59) hereditary ATTR (genetic study: variant E54Q and mutation c.424> A (p.Va.122Ile) in exon 4 of TTR) and 1.7% (1/59) secondary amyloidosis. The remaining 34/59 (57.7%) cases were undetermined amyloidosis (6 positive immunofixation and 27 without monoclonal proteins determination). Conclusion: Determination of monoclonal bands in blood and urine is mandatory to correctly characterize cases of cardiac amyloidosis and, in presence of monoclonal bands, to assess the existence of underlying haematological malignancies

    Managing healthcare budgets in times of austerity: the role of program budgeting and marginal analysis

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    Given limited resources, priority setting or choice making will remain a reality at all levels of publicly funded healthcare across countries for many years to come. The pressures may well be even more acute as the impact of the economic crisis of 2008 continues to play out but, even as economies begin to turn around, resources within healthcare will be limited, thus some form of rationing will be required. Over the last few decades, research on healthcare priority setting has focused on methods of implementation as well as on the development of approaches related to fairness and legitimacy and on more technical aspects of decision making including the use of multi-criteria decision analysis. Recently, research has led to better understanding of evaluating priority setting activity including defining ‘success’ and articulating key elements for high performance. This body of research, however, often goes untapped by those charged with making challenging decisions and as such, in line with prevailing public sector incentives, decisions are often reliant on historical allocation patterns and/or political negotiation. These archaic and ineffective approaches not only lead to poor decisions in terms of value for money but further do not reflect basic ethical conditions that can lead to fairness in the decision-making process. The purpose of this paper is to outline a comprehensive approach to priority setting and resource allocation that has been used in different contexts across countries. This will provide decision makers with a single point of access for a basic understanding of relevant tools when faced with having to make difficult decisions about what healthcare services to fund and what not to fund. The paper also addresses several key issues related to priority setting including how health technology assessments can be used, how performance can be improved at a practical level, and what ongoing resource management practice should look like. In terms of future research, one of the most important areas of priority setting that needs further attention is how best to engage public members

    Development of a Sentinel-2 burned area algorithm: Generation of a small fire database for sub-Saharan Africa

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    A locally-adapted multitemporal two-phase burned area (BA) algorithm has been developed using as inputs Sentinel-2 MSI reflectance measurements in the short and near infrared wavebands plus the active fires detected by Terra and Aqua MODIS sensors. An initial burned area map is created in the first step, from which tile dependent statistics are extracted for the second step. The whole Sub-Saharan Africa (around 25 M km(2)) was processed with this algorithm at a spatial resolution of 20 m, from January to December 2016. This period covers two half fire seasons on the Northern Hemisphere and an entire fire season in the South. The area was selected as existing BA products account it to include around 70% of global BA. Validation of this product was based on a two-stage stratified random sampling of Landsat multitemporal images. Higher accuracy values than existing global BA products were observed, with Dice coefficient of 77% and omission and commission errors of 26.5% and 19.3% respectively. The standard NASA BA product (MCD64A1 c6) showed a similar commission error (20.4%), but much higher omission errors (59.6%), with a lower Dice coefficient (53.6%). The BA algorithm was processed over > 11,000 Sentinel-2 images to create a database that would also include small fires (< 100 ha). This is the first time a continental BA product is generated from medium resolution sensors (spatial resolution = 20 m), showing their operational potential for improving our current understanding of global fire impacts. Total BA estimated from our product was 4.9 M km(2), around 80% larger area than what the NASA BA product (MCD64A1 c6) detected in the same period (2.7 M km(2)). The main differences between the two products were found in regions where small fires (< 100 ha) account for a significant proportion of total BA, as global products based on coarse pixel sizes (500 m for MCD64A1) unlikely detect them. On the negative side, Sentinel-2 based products have lower temporal resolution and consequently are more affected by cloud/cloud shadows and have less temporal reporting accuracy than global BA products. The product derived from S2 imagery would greatly contribute to better understanding the impacts of small fires in global fire regimes, particularly in tropical regions, where such fires are frequent. This product is named FireCCISFD11 and it is publicly available at: https://www.esa-fire-cci.org/node/262, last accessed on November 2018.This research was carried out within the Fire_cci project (https://www.esa-fire-cci.org/, last accessed on November 2018), contract no. 4000115006/15/I-NB, which has been funded by the European Space Agency (ESA) under the Climate Change Initiative Programme. The FireCCISFD11 product can be downloaded at https://www.esa-fire-cci.org/node/262 (last accessed on November 2018)

    Alpha-particle Emission Probabilities in the Decay of 235U

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    235U decays by alpha particle emission to 23I Th. The decay scheme of this nuclide is very complex, with more than 20 alpha branches. Recommended values for Palpha of this nuclide are based on measurements carried out in 1975. This work presents the results of new measurements made with SI detectors and sources of enriched uranium in the frame of the EUROMET 591 cooperation project. The use of improved measurement techniques and numerical analysis of spectra allowed a new set of P alpha values for 13 lines with improved uncertainties to be obtained.JRC.D.4-Isotope measurement
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