252 research outputs found
DEVELOPMENT OF COBALT-FREE HIGH ENERGY DENSITY POSITIVE ELECTRODE MATERIALS FOR LI-ION BATTERIES
No full textThe positive electrode constitutes a key component of the Li-ion cell and helps determine the energy density and cost of the cell. Co-rich positive electrode active materials have been widely commercialized, with proven success, and maintain a reliable performance record across markets. And yet, due to economic reasons and ethical concerns, Li-ion manufacturers are turning to Co- free, Ni-rich materials. But eliminating Co is not without its drawbacks. Co-free, Ni-rich materials can deliver high capacity; they can also deliver long lifetime. However, it has been challenging to design materials that can deliver both simultaneously. Besides the fact that electrode materials with both high capacity and long lifetime are more attractive to consumers, they also provide an environmentally sustainable solution. Using higher energy density materials reduces the size of the cell or the number of cells needed to make battery systems. Increasing the lifetime of the cell extends the period until the cell needs to be disposed of or recycled and reduces the rate at which critical metals need to be mined and treated to make new cells.
This work extensively examines the effects of Al and W in LiNi1-xMnxO2 (NM) systems and optimizes the material to increase both the gravimetric capacity and cycle life of the cell. Since Ni- rich materials are susceptible to reactions with water, the materials are characterized thoroughly with a focus on the surface’s sensitivity to moisture and washing. Furthermore, this work demonstrates that greater attention needs to be paid to the mechanical properties of the material particles to identify, in a time-efficient manner, the propensity of the material to crack and, in turn, better understand the degradation mechanisms of the electrode. When studying Ni-rich materials, the safety of the material is also of interest; the thermal stability of the materials at a high state of charge were characterized and reported in this work. Through these methods, Co-free, Ni-rich materials were designed with high energy density and impressive charge-discharge capacity retention
Suberin deficiency and its effect on the transport physiology of young poplar roots
No full textSummary
The precise functions of suberized apoplastic barriers in root water and nutrient transport physiology have not fully been elucidated. While lots of research has been performed with mutants of
Arabidopsis
, little to no data are available for mutants of agricultural crop or tree species.
By employing a combined set of physiological, histochemical, analytical, and transport physiological methods as well as RNA‐sequencing, this study investigated the implications of remarkable CRISPR/Cas9‐induced suberization defects in young roots of the economically important gray poplar.
While barely affecting overall plant development, contrary to literature‐based expectations significant root suberin reductions of up to 80–95% in four independent mutants were shown to not evidently affect the root hydraulic conductivity during non‐stress conditions. In addition, subliminal iron deficiency symptoms and increased translocation of a photosynthesis inhibitor as well as NaCl highlight the involvement of suberin in nutrient transport physiology.
The multifaceted nature of the root hydraulic conductivity does not allow drawing simplified conclusions such as that the suberin amount must always be correlated with the water transport properties of roots. However, the decreased masking of plasma membrane surface area could facilitate the uptake but also leakage of beneficial and harmful solutes.Deutsche Forschungsgemeinschaft https://doi.org/10.13039/501100001659National Natural Science Foundation of China https://doi.org/10.13039/50110000180
Symmetry breaking for maximum satisfiability
No full textSymmetries are intrinsic to many combinatorial problems including Boolean Satisfiability (SAT) and Constraint Programming (CP). In SAT, the identification of symmetry breaking predicates (SBPs) is a well-known, often effective, technique for solving hard problems. The identification of SBPs in SAT has been the subject of significant improvements in recent years, resulting in more compact SBPs and more effective algorithms. The identification of SBPs has also been applied to pseudo-Boolean (PB) constraints, showing that symmetry breaking can also be an effective technique for PB constraints. This paper extends further the application of SBPs, and shows that SBPs can be identified and used in Maximum Satisfiability (MaxSAT), as well as in its most well-known variants, including partial MaxSAT, weighted MaxSAT and weighted partial MaxSAT. As with SAT and PB, symmetry breaking predicates for MaxSAT and variants are shown to be effective for a representative number of problem domains, allowing solving problem instances that current state of the art MaxSAT solvers could not otherwise solv
Food from peace: breaking the links between conflict and hunger
No full text"In this paper, Ellen Messer, Marc J. Cohen, and Jashinta D'Costa show how hunger is often a direct result of violence ... [and] how hunger can reciprocally cause conflict. ... The authors call for including conflict prevention in food security and development efforts, as well as new linkages between food security and development on the one hand, and emergency relief on the other" Foreword.Social conflict., Hunger., Conflict management.,
NADPH oxidase (NOX) in the heart : the interplay of NOX-derived ROS in β1-integrin-induced survival signalling
No full textModerate levels of reactive oxygen species (ROS) act as mediators in cellular signalling processes. An important source of cardiac ROS is the highly expressed NADPH oxidase (NOX) family isoform NOX2. However, little is known about whether NOX-derived ROS are protective in the heart.
In this study we show that CD29 (β1-integrin), a cell adhesion receptor highly expressed on cardiac muscle cells, induces NOX-dependent ROS. CD29 is known to be mandatory in cell growth and survival, and non-functional CD29 causes severe heart disease. We demonstrate that NOX2-derived ROS are essential for CD29-induced survival signalling, including the PI3K/PKB and MEK/ERK pathways. Furthermore, CD29-induced NOX-derived ROS are indispensible in the inhibition of the pro-apoptotic kinase GSK-3β, which we uncovered as a downstream target of both the ERK and PKB survival pathways in cardiac muscle cells. These findings clearly add to the growing body of evidence suggesting that moderate ROS levels are beneficial to the cell and highlight the crucial role of NOX2-derived ROS for cell survival in the heart
Some Citizenship issues as a Phenomenon in International Sports Law
No full textI u grupnim i u individualnim sportovima, proces olakšane naturalizacije sportaša uzima sve više maha. Budući da sportaši moraju posjedovati državljanstvo određene države da bi je mogli predstavljati na međunarodnim natjecanjima, mnoge države pribjegavaju ovoj praksi te nude posebne vrste viza ili olakšani postupak naturalizacije za „obećavajuće“ sportaše. Ista je situacija vezana i uz nastupanje na Olimpijskim igrama. Najčešće se radi o stranim sportašima koji su članovi nacionalnih sportskih timova država čiji su državljani, a od kojih se očekuje da bi mogli nastupati za nacionalni tim države u koju dolaze kao sportaši stranci. I dok jedni u ovakvom razvoju događaja ne vide ništa loše, drugi pozivaju na ozbiljno promišljanje o „utjecaju pojačane mobilnosti sportaša na pretpostavljenu vezu između odanosti, identiteta i državljanstva“. Stoga autorica u ovom tekstu pokušava odgovoriti na sljedeća pitanja: U kojoj mjeri globalizacija i transnacionalizacija sporta mijenjaju našu percepciju državljanstva i pripadanja? Je li postojeći koncept državljanstva adekvatan i u sportskom kontekstu? Treba li intervenirati u odnos državljanstva i sporta?In group and individual sports, the process of easier naturalisation of athletes is gathering greater momentum. Given that athletes must hold citizenship of a particular country in order to represent that country at international competitions, many countries lean towards this practice and offer many special visas or an eased naturalisation procedure for „promising “ athletes. It is the same situation for performing at Olympic Games. It most often concerns foreign athletes who are members of national sport teams of the countries of which they are citizens who are expected to perform for the national team of the country they come to as foreign athletes. And while some in this situation do not perceive it as being bad, others call for serious consideration of the „ potential mobility of athletes on the expected relationship among loyalty, identity and citizenship“. Therefore, the author attempts in this paper to answer the following questions: To what extent does globalisation and transnationalisation of sport change our perception of citizenship and belongingness? Is the existing concept of citizenship also adequate in the sports context? Does one need to intervene in the relationship between citizenship and sport
How many focus markers are there in Konkomba?
No full textThis article discusses the divergent status of the two particles lé and lá in the grammar of Konkomba, a Gur language (Niger-Congo) of the Gurma subgroup. While previous studies claim that both particles are focus markers, this author argues that only the particle lá should be analyzed as a pure pragmatic device. Distributional studies suggest that the use of particle lé, on the other hand, is only required under specific focus conditions, and primarily represents a syntactic device
Effekte der Sprachlernerfahrung auf den Erwerb einer „Neue Medien-Kompetenz“. Eine Fallstudie zur medienpädagogischen Aus- und Weiterbildung von Deutsch-als-Fremdsprache-Lehrkräften
No full textNeue Medien sind Teil der modernen deutschen Gesellschaft und Träger von Kultur und Sprache über Landesgrenzen hinaus. In kei¬ner Fremdsprachendidaktik sind neue Medien ein so aktuelles Thema wie in der deutschen. Tatsächlich sind die Wissens- und Fähigkeitsbestände aber unterschiedlich.Die Förderung einer „Neue Medien-Kompetenz” ist ein Anliegen der Autorin. Darum bietet dieser Artikel a) eine Zusammenfassung theoretischer und praktischer Erkenntnisse in Form eines mög¬li¬chen „idealen” Weiterbildungsmodells für Deutsch-als-Fremd¬spra¬che-Lehrkräfte sowie b) die Auswertung einer Durchführung in ab¬gewandelter Form und c) gewonnene Erkenntnisse aus der damit verbundenen Erhebung.
New Media are part of a modern German society. They carry culture and language across countries\u27 borders. Recently, no foreign language didactics foster new media as much as the German as foreign language (GFL) didactics. But practically, the knowledge and skill sets are different.To advance a "New Media Competence" is an interest of the author. Therefore, this article offers a) a summary of theoretical and practical insights concluding in a possible and ideal further education model for GFL-teachers, b) the evaluation of an adapted implementation, and c) insights gained from the data collected within this implementation
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