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[en] Drought is the primary cause of yield loss in agriculture throughout the world and is currently the most common reason for global food shortages and food insecurity. The estimated cost of drought across Africa over the period of 2014 to 2017 totalled USD$ 372 billion. Climate change is expected to increase drought severity and its negative effect. The impact of drought is particularly severe in Sub-Saharan Africa (SSA) where rainfed subsistence farming dominates food production and the social and economic disaster management systems are usually inadequate. An increase in crop yields is required to meet the needs of a growing population.The aim of the project is to use induced genetic variation for mutation breeding with the use of optimal phenotyping systems to improve cowpea adaptation to drought. It is expected to lead to the release of high-yielding cowpea varieties tolerant to drought stress.
[en] Titanium and titanium pigments have very good potential growth in India with the demand surging in the end use sectors. The country has substantial raw materials and the wherewith al to produce. So is the case with zirconium. However, challenges include meeting environmental issues related to mining and also the need to obtain state of the art technologies for cleaner and cost-efficient processing. In this article, a detailed scenario is presented along with production and demand situation, the new projects on the anvil and application areas. (author)
[en] We analyzed the effect of the use of Eye Protective Equipment (EPE) and the best position to use individual dosimeters to estimate the eye lens radiation dose to a medical staff that works with yttrium-90. Three Alderson-Head-Phantoms were exposed to 58 MBq of Y for 24 h, in two different experiments: (1) at different dosimeter placements and (2) with and without the use of EPE. The measurements were carried on by thermoluminescent technique. Doses received by dosimeters on both lenses were more closely represented by the ones placed between the eyes than those on the temples, which underestimated the doses by a factor of 3. Also, the transmission factors showed that the EPE was able to reduce the H(3) values from about 78% to 92%. This study demonstrated that the use of EPE can optimize the Y eye lens dose. An individual dosimeter should be worn between the eyes for an appropriate estimate of this equivalent dose.
[en] The development of metal oxide-based electron transport layers in perovskite solar cells (PSCs) has received intensive research interest for achieving high-efficiency PSCs. Herein, TiO nanorods (TiO NRs) are grown on TiO seed layers coated on fluorine-doped tin oxide (FTO) glass substrate by using a hydrothermal method and then are utilized as the electronic transport layer in PSCs. The main concern, after hydrothermal growth of TiO NRs, is that their crystallinity can be improved by a sequential high-temperature treatment at 450 °C. In addition to high-temperature annealing, a low-temperature treatment with boiling water, which is expected to clean the surface of the TiO NRs, is developed. In this contribution, the champion PSCs are those based on TiO NRs where boiling water treatment achieves a maximum power conversion efficiency (PCE) of 15.50%, whereas a PCE of 12.91% is obtained from PSCs based on TiO NRs with high-temperature annealing. The remarkable ease of using a water-assisted process offers an efficient approach to the removal of residuals adsorbed on the surface and circumvents the disadvantage of a thermal annealing method resulting in high-production costs. This low-temperature treatment can be used to improve TiO films in flexible PSCs. (© 2020 Wiley‐VCH GmbH)
[en] A CIRED team has just published a study on how to meet the demand for electricity without nuclear or fossil fuels. She concluded that it would not cost more than it does today. With the hypotheses of the cost of wind power and photovoltaics that it has retained, it is also possible to calculate that it would cost less than with new nuclear reactors. In addition to the costs of wind and photovoltaic production, the CIRED study retains a set of explicit or implicit assumptions which deserve to be commented on the level of electric power consumption, the stability of the network, the efficiency of the storage means, the reception by the population of tens of thousands of wind turbines and thousands of square kilometers of photovoltaics, the consumption of critical materials and dependence on foreign countries, the loss of a nuclear know-how that the world will need, the vulnerability of an electrical network based on digital communications.
[fr]Une equipe du CIRED vient de publier une etude sur la facon de repondre a la demande d'electricite sans nucleaire ni energie fossile. Elle conclut que cela ne couterait pas plus cher qu'aujourd'hui. Avec les hypotheses de cout de l'eolien et de photovoltaique qu'elle a retenues on peut aussi calculer que cela couterait moins cher qu'avec des nouveaux reacteurs nucleaires. Outre les couts de production eolien et photovoltaique, l'etude du CIRED retient un ensemble d'hypotheses explicites ou implicites qui meritent d'etre commentees sur le niveau de consommation d'electricite, la stabilite du reseau, l'efficacite des moyens de stockage, l'accueil par la population de dizaines de milliers d'eoliennes et de milliers de kilometres carre de photovoltaique, la consommation de materiaux critiques et la dependance a l'egard de l'etranger, la perte d'un savoir faire nucleaire dont le monde aura besoin, la vulnerabilite d'un reseau electrique reposant sur les communications numeriques. (auteur)
[en] While France and a growing number of countries around the world have been setting ambitious goals for reaching net-zero emissions, variable renewables like wind and solar energy are set to become the main building blocks in power systems worldwide as countries seek to decarbonise their economies. In a new joint analysis commissioned by the French Ministry for the Ecological Transition, the IEA (International Energy Agency) and RTE (Reseau de Transport d'Electricite) describe four essential areas that policy makers must address when wind and solar PV start to dominate electricity generation. The new report, Conditions and requirements for the technical feasibility of a power system with a high share of renewables in France towards 2050, outlines four groups of strict conditions that need to be met to integrate very high shares of renewables in a technically secure way in a large and meshed power system such as that of France. - Power system strength: Even if they still need to be proven at large scale, there is a general scientific consensus that technological solutions to maintain system strength - and therefore stability - without conventional generation exist in several cases. Specific difficulties are expected in the case of a system with a significant share of distributed solar PV. Further assessment of the impacts of distributed PV on the power distribution network and their implications for electricity security is needed. - System adequacy: This is the ability of a power system to cope with a given load at all times. It can be ensured even in a system mainly based on variable renewables as long as substantial sources of flexibility are available, including demand-response, large-scale storage, peak generation units and well-developed transmission networks and interconnections. The maturity, availability and cost of different flexibility mixes need to be evaluated in further analysis. - Operational reserves: The sizing of these reserves and the regulatory framework for balancing responsibilities and procurement would need to be substantially revised in a large power system as such that of France. Moreover, forecasting methods for variable renewables would need to be continually improved. - Grid development: Substantial efforts would be necessary beyond 2030 at both transmission and distribution levels. This requires strong proactive steps and public engagement in long-term planning in order to assess costs and work with citizens on social acceptance of new infrastructure. These efforts can nonetheless be partly integrated into the renewal of ageing network assets. The joint study marks an important step and is part of a larger work program aimed at developing and comparing scenarios for the long-term transformation of the electricity system to achieve carbon neutrality by 2050. On 27 January 2021, RTE will open a public consultation assessing the framework and assumptions of these future scenarios, and will present the conclusions of this consultation in the Fall 2021.
[en] PET/MRI has recently been introduced into clinical practice. We prospectively investigated the clinical impact of PET/MRI compared with PET/CT, in a mixed population of cancer patients, and performed an economic evaluation of PET/MRI. Cancer patients referred for routine staging or follow-up by PET/CT underwent consecutive PET/CT and PET/MRI, using single applications of [F]FDG, [Ga]Ga-DOTANOC, or [F]FDOPA, depending on tumor histology. PET/MRI and PET/CT were rated separately, and lesions were assessed per anatomic region; based on regions, per-examination and per-patient accuracies were determined. A simulated, multidisciplinary team meeting served as reference standard and determined whether differences between PET/CT and PET/MRI affected patient management. The McNemar tests were used to compare accuracies, and incremental cost-effectiveness ratios (ICERs) for PET/MRI were calculated. Two hundred sixty-three patients (330 same-day PET/CT and PET/MRI examinations) were included. PET/MRI was accurate in 319/330 examinations and PET/CT in 277/330 examinations; the respective accuracies of 97.3% and 83.9% differed significantly (P < 0.001). The additional findings on PET/MRI - mainly liver and brain metastases - had implications for patient management in 21/263 patients (8.0%). The per-examination cost was 596.97 EUR for PET/MRI and 405.95 EUR for PET/CT. ICERs for PET/MRI were 14.26 EUR per percent of diagnostic accuracy and 23.88 EUR per percent of correctly managed patients. PET/MRI enables more appropriate management than PET/CT in a nonnegligible fraction of cancer patients. Since the per-examination cost is about 50% higher for PET/MRI than for PET/CT, a histology-based triage of patients to either PET/MRI or PET/CT may be meaningful.
[en] In Europe, lung cancer ranks third among the most common cancers, remaining the biggest killer. Since the publication of the first European Society of Radiology and European Respiratory Society joint white paper on lung cancer screening (LCS) in 2015, many new findings have been published and discussions have increased considerably. Thus, this updated expert opinion represents a narrative, non-systematic review of the evidence from LCS trials and description of the current practice of LCS as well as aspects that have not received adequate attention until now. Reaching out to the potential participants (persons at high risk), optimal communication and shared decision-making will be key starting points. Furthermore, standards for infrastructure, pathways and quality assurance are pivotal, including promoting tobacco cessation, benefits and harms, overdiagnosis, quality, minimum radiation exposure, definition of management of positive screen results and incidental findings linked to respective actions as well as cost-effectiveness. This requires a multidisciplinary team with experts from pulmonology and radiology as well as thoracic oncologists, thoracic surgeons, pathologists, family doctors, patient representatives and others. The ESR and ERS agree that Europe’s health systems need to adapt to allow citizens to benefit from organised pathways, rather than unsupervised initiatives, to allow early diagnosis of lung cancer and reduce the mortality rate. Now is the time to set up and conduct demonstration programmes focusing, among other points, on methodology, standardisation, tobacco cessation, education on healthy lifestyle, cost-effectiveness and a central registry.
[en] Following ratification of the Paris Climate Agreement, the European Union reasserted its determination to 'de-carbonize' its energy mix by 2050. As various studies have shown, this entails increasing the share of electricity in final uses and removing carbon from the processes for generating electricity. To quantify the nuclear industry's potential contribution to the goal of a low-carbon economy, a study requested by FORATOM (presented in this article) has drafted three contrasting scenarios about the capacity for producing nuclear electricity in Europe. These scenarios for achieving 'decarbonization' are analyzed and assessed using several criteria. The nuclear industry thus turns out to be a big contributor to the energy transition; in particular. This study sheds light on the difficulties and extra costs that would result from a scenario with a low share of nuclear energy, in which the life span of existing nuclear power stations would not be prolonged. (authors)
[en] Several work sites where the first reactors of the third generation are being built have encountered major difficulties with several causes. This can, in large part, be set down to the absence, for twenty years now, of big programs of this sort in the United States and Europe. The costs of the first reactors of a new generation have ballooned. Thanks to accumulated feedback, this article shows how and why tomorrow's nuclear industry will be competitive, not only as it already is in Asia but also in other geographic zones. The range of economic results presented herein is coherent with public authorities' strategic analyses. The findings are: that a program for updating France's fleet of nuclear reactors is needed and should be started fast; that the closed cycle should be pursued; and that the first phase of the Cigeo Plan (for a nuclear waste repository) should be launched. (authors)