bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microscopic origins of performance losses in highly efficient Cu(In,Ga)Se2 thin-film solar cells
Authors: Krause Maximilian , Nikolaeva Aleksandra , Maiberg Matthias , Jackson Philip , Hariskos Dimitrios , Witte Wolfram , Márquez José A. , Levcenko Sergej , Unold Thomas , Scheer Roland , Abou-Ras Daniel 
Published: August 2020

AbstractThin-film solar cells based on polycrystalline absorbers have reached very high conversion efficiencies of up to 23-25%. In order to elucidate the limiting factors that need to be overcome for even higher efficiency levels, it is essential to investigate microscopic origins of loss mechanisms in these devices. In the present work, a high efficiency (21% without anti-reflection coating) copper indium gallium diselenide (CIGSe) solar cell is characterized by means of a correlative microscopy approach and corroborated by means of photoluminescence spectroscopy. The values obtained by the experimental characterization are used as input parameters for two-dimensional device simulations, for which a real microstructure was used. It can be shown that electrostatic potential and lifetime fluctuations exhibit no substantial impact on the device performance. In contrast, nonradiative recombination at random grain boundaries can be identified as a significant loss mechanism for CIGSe solar cells, even for devices at a very high performance level.
Real-space recipes for general topological crystalline states
Authors: Song Zhida , Fang Chen , Qi Yang 
Published: August 2020

AbstractTopological crystalline states (TCSs) are short-range entangled states jointly protected by onsite and crystalline symmetries. Here we present a unified scheme for constructing all TCSs, bosonic and fermionic, free and interacting, from real-space building blocks and connectors. Building blocks are lower-dimensional topological states protected by onsite symmetries alone, and connectors are glues that complete the open edges shared by two or multiple building blocks. The resulted assemblies are selected against two physical criteria we call the no-open-edge condition and the bubble equivalence. The scheme is then applied to obtaining the full classification of bosonic TCSs protected by several onsite symmetry groups and each of the 17 wallpaper groups in two dimensions and 230 space groups in three dimensions. We claim that our construction scheme can give the complete set of TCSs for bosons and fermions, and prove the boson case analytically using a spectral-sequence expansion.
Independent phase modulation for quadruplex polarization channels enabled by chirality-assisted geometric-phase metasurfaces
Authors: Yuan Yueyi , Zhang Kuang , Ratni Badreddine , Song Qinghua , Ding Xumin , Wu Qun , Burokur Shah Nawaz , Genevet Patrice 
Published: August 2020

AbstractGeometric-phase metasurfaces, recently utilized for controlling wavefronts of circular polarized (CP) electromagnetic waves, are drastically limited to the cross-polarization modality. Combining geometric with propagation phase allows to further control the co-polarized output channel, nevertheless addressing only similar functionality on both co-polarized outputs for the two different CP incident beams. Here we introduce the concept of chirality-assisted phase as a degree of freedom, which could decouple the two co-polarized outputs, and thus be an alternative solution for designing arbitrary modulated-phase metasurfaces with distinct wavefront manipulation in all four CP output channels. Two metasurfaces are demonstrated with four arbitrary refraction wavefronts, and orbital angular momentum modes with four independent topological charge, showcasing complete and independent manipulation of all possible CP channels in transmission. This additional phase addressing mechanism will lead to new components, ranging from broadband achromatic devices to the multiplexing of wavefronts for application in reconfigurable-beam antenna and wireless communication systems.
Direct insights into the role of epoxy groups on cobalt sites for acidic H2O2 production
Authors: Zhang Qingran , Tan Xin , Bedford Nicholas M. , Han Zhaojun , Thomsen Lars , Smith Sean , Amal Rose , Lu Xunyu 
Published: August 2020

AbstractHydrogen peroxide produced by electrochemical oxygen reduction reaction provides a potentially cost effective and energy efficient alternative to the industrial anthraquinone process. In this study, we demonstrate that by modulating the oxygen functional groups near the atomically dispersed cobalt sites with proper electrochemical/chemical treatments, a highly active and selective oxygen reduction process for hydrogen peroxide production can be obtained in acidic electrolyte, showing a negligible amount of onset overpotential and nearly 100% selectivity within a wide range of applied potentials. Combined spectroscopic results reveal that the exceptionally enhanced performance of hydrogen peroxide generation originates from the presence of epoxy groups near the Co–N4 centers, which has resulted in the modification of the electronic structure of the cobalt atoms. Computational modeling demonstrates these electronically modified cobalt atoms will enhance the hydrogen peroxide productivity during oxygen reduction reaction in acid, providing insights into the design of electroactive materials for effective peroxide production.
The mechanism of activation of the actin binding protein EHBP1 by Rab8 family members
Authors: Rai Amrita , Bleimling Nathalie , Vetter Ingrid R. , Goody Roger S. 
Published: August 2020

AbstractEHBP1 is an adaptor protein that regulates vesicular trafficking by recruiting Rab8 family members and Eps15-homology domain-containing proteins 1/2 (EHD1/2). It also links endosomes to the actin cytoskeleton. However, the underlying molecular mechanism of activation of EHBP1 actin-binding activity is unclear. Here, we show that both termini of EHBP1 have membrane targeting potential. EHBP1 associates with PI(3)P, PI(5)P, and phosphatidylserine via its N-terminal C2 domain. We show that in the absence of Rab8 family members, the C-terminal bivalent Mical/EHBP Rab binding (bMERB) domain forms an intramolecular complex with its central calponin homology (CH) domain and auto-inhibits actin binding. Rab8 binding to the bMERB domain relieves this inhibition. We have analyzed the CH:bMERB auto-inhibited complex and the active bMERB:Rab8 complex biochemically and structurally. Together with structure-based mutational studies, this explains how binding of Rab8 frees the CH domain and allows it to interact with the actin cytoskeleton, leading to membrane tubulation.
Behavioral and neuronal underpinnings of safety in numbers in fruit flies
Authors: Ferreira Clara H. , Moita Marta A. 
Published: August 2020

AbstractLiving in a group allows individuals to decrease their defenses, enabling other beneficial behaviors such as foraging. The detection of a threat through social cues is widely reported, however, the safety cues that guide animals to break away from a defensive behavior and resume alternate activities remain elusive. Here we show that fruit flies display a graded decrease in freezing behavior, triggered by an inescapable threat, with increasing group sizes. Furthermore, flies use the cessation of movement of other flies as a cue of threat and its resumption as a cue of safety. Finally, we find that lobula columnar neurons, LC11, mediate the propensity for freezing flies to resume moving in response to the movement of others. By identifying visual motion cues, and the neurons involved in their processing, as the basis of a social safety cue this study brings new insights into the neuronal basis of safety in numbers.
Pumping up the charge density of a triboelectric nanogenerator by charge-shuttling
Authors: Wang Huamei , Xu Liang , Bai Yu , Wang Zhong Lin 
Published: August 2020

AbstractAs an emerging technology for harvesting mechanical energy, low surface charge density greatly hinders the practical applications of triboelectric nanogenerators (TENGs). Here, a high-performance TENG based on charge shuttling is demonstrated. Unlike conventional TENGs with static charges fully constrained on the dielectric surface, the device works based on the shuttling of charges corralled in conduction domains. Driven by the interaction of two quasi-symmetrical domains, shuttling of two mirror charge carriers can be achieved to double the charge output. Based on the mechanism, an ultrahigh projected charge density of 1.85 mC m−2 is obtained in ambient conditions. An integrated device for water wave energy harvesting is also presented, confirming its feasibility for practical applications. The device provides insights into new modes of TENGs using unfixed charges in domains, shedding a new light on high-performance mechanical energy harvesting technology.
OTUD5 cooperates with TRIM25 in transcriptional regulation and tumor progression via deubiquitination activity
Authors: Li Fangzhou , Sun Qianqian , Liu Kun , Zhang Ling , Lin Ning , You Kaiqiang , Liu Mingwei , Kon Ning , Tian Feng , Mao Zebin , Li Tingting , Tong Tanjun , Qin Jun , Gu Wei , Li Dawei , Zhao Wenhui 
Published: August 2020

AbstractOncogenic processes exert their greatest effect by targeting regulators of cell proliferation. Studying the mechanism underlying growth augmentation is expected to improve clinical therapies. The ovarian tumor (OTU) subfamily deubiquitinases have been implicated in the regulation of critical cell-signaling cascades, but most OTUs functions remain to be investigated. Through an unbiased RNAi screen, knockdown of OTUD5 is shown to significantly accelerate cell growth. Further investigation reveals that OTUD5 depletion leads to the enhanced transcriptional activity of TRIM25 and the inhibited expression of PML by altering the ubiquitination level of TRIM25. Importantly, OTUD5 knockdown accelerates tumor growth in a nude mouse model. OTUD5 expression is markedly downregulated in tumor tissues. The reduced OTUD5 level is associated with an aggressive phenotype and a poor clinical outcome for cancers patients. Our findings reveal a mechanism whereby OTUD5 regulates gene transcription and suppresses tumorigenesis by deubiquitinating TRIM25, providing a potential target for oncotherapy.
Frataxin gene editing rescues Friedreich’s ataxia pathology in dorsal root ganglia organoid-derived sensory neurons
Authors: Mazzara Pietro Giuseppe , Muggeo Sharon , Luoni Mirko , Massimino Luca , Zaghi Mattia , Valverde Parisa Tajalli-Tehrani , Brusco Simone , Marzi Matteo Jacopo , Palma Cecilia , Colasante Gaia , Iannielli Angelo , Paulis Marianna , Cordiglieri Chiara , Giannelli Serena Gea , Podini Paola , Gellera Cinzia , Taroni Franco , Nicassio Francesco , Rasponi Marco , Broccoli Vania 
Published: August 2020

AbstractFriedreich’s ataxia (FRDA) is an autosomal-recessive neurodegenerative and cardiac disorder which occurs when transcription of the FXN gene is silenced due to an excessive expansion of GAA repeats into its first intron. Herein, we generate dorsal root ganglia organoids (DRG organoids) by in vitro differentiation of human iPSCs. Bulk and single-cell RNA sequencing show that DRG organoids present a transcriptional signature similar to native DRGs and display the main peripheral sensory neuronal and glial cell subtypes. Furthermore, when co-cultured with human intrafusal muscle fibers, DRG organoid sensory neurons contact their peripheral targets and reconstitute the muscle spindle proprioceptive receptors. FRDA DRG organoids model some molecular and cellular deficits of the disease that are rescued when the entire FXN intron 1 is removed, and not with the excision of the expanded GAA tract. These results strongly suggest that removal of the repressed chromatin flanking the GAA tract might contribute to rescue FXN total expression and fully revert the pathological hallmarks of FRDA DRG neurons.
An excess of niche differences maximizes ecosystem functioning
Authors: Godoy Oscar , Gómez-Aparicio Lorena , Matías Luis , Pérez-Ramos Ignacio M. , Allan Eric 
Published: August 2020

AbstractEcologists have long argued that higher functioning in diverse communities arises from the niche differences stabilizing species coexistence and from the fitness differences driving competitive dominance. However, rigorous tests are lacking. We couple field-parameterized models of competition between 10 annual plant species with a biodiversity-functioning experiment under two contrasting environmental conditions, to study how coexistence determinants link to biodiversity effects (selection and complementarity). We find that complementarity effects positively correlate with niche differences and selection effects differences correlate with fitness differences. However, niche differences also contribute to selection effects and fitness differences to complementarity effects. Despite this complexity, communities with an excess of niche differences (where niche differences exceeded those needed for coexistence) produce more biomass and have faster decomposition rates under drought, but do not take up nutrients more rapidly. We provide empirical evidence that the mechanisms determining coexistence correlate with those maximizing ecosystem functioning.
Interface chemistry of an amide electrolyte for highly reversible lithium metal batteries
Authors: Wang Qidi , Yao Zhenpeng , Zhao Chenglong , Verhallen Tomas , Tabor Daniel P. , Liu Ming , Ooms Frans , Kang Feiyu , Aspuru-Guzik Alán , Hu Yong-Sheng , Wagemaker Marnix , Li Baohua 
Published: August 2020

AbstractMetallic lithium is a promising anode to increase the energy density of rechargeable lithium batteries. Despite extensive efforts, detrimental reactivity of lithium metal with electrolytes and uncontrolled dendrite growth remain challenging interconnected issues hindering highly reversible Li-metal batteries. Herein, we report a rationally designed amide-based electrolyte based on the desired interface products. This amide electrolyte achieves a high average Coulombic efficiency during cycling, resulting in an outstanding capacity retention with a 3.5 mAh cm−2 high-mass-loaded LiNi0.8Co0.1Mn0.1O2 cathode. The interface reactions with the amide electrolyte lead to the predicted solid electrolyte interface species, having favorable properties such as high ionic conductivity and high stability. Operando monitoring the lithium spatial distribution reveals that the highly reversible behavior is related to denser deposition as well as top-down stripping, which decreases the formation of porous deposits and inactive lithium, providing new insights for the development of interface chemistries for metal batteries.
Associations between aversive learning processes and transdiagnostic psychiatric symptoms in a general population sample
Authors: Wise Toby , Dolan Raymond J. 
Published: August 2020

AbstractSymptom expression in psychiatric conditions is often linked to altered threat perception, however how computational mechanisms that support aversive learning relate to specific psychiatric symptoms remains undetermined. We answer this question using an online game-based aversive learning task together with measures of common psychiatric symptoms in 400 subjects. We show that physiological symptoms of anxiety and a transdiagnostic compulsivity-related factor are associated with enhanced safety learning, as measured using a probabilistic computational model, while trait cognitive anxiety symptoms are associated with enhanced learning from danger. We use data-driven partial least squares regression to identify two separable components across behavioural and questionnaire data: one linking enhanced safety learning and lower estimated uncertainty to physiological anxiety, compulsivity, and impulsivity; the other linking enhanced threat learning and heightened uncertainty estimation to symptoms of depression and social anxiety. Our findings implicate aversive learning processes in the expression of psychiatric symptoms that transcend diagnostic boundaries.
Room-temperature formation of CdS magic-size clusters in aqueous solutions assisted by primary amines
Authors: Wan Wushuang , Zhang Meng , Zhao Min , Rowell Nelson , Zhang Chunchun , Wang Shanling , Kreouzis Theo , Fan Hongsong , Huang Wen , Yu Kui 
Published: August 2020

AbstractAqueous-phase approaches to semiconductor CdS magic-size clusters (MSCs) and the formation pathway have remained relatively unexplored. Here, we report the demonstration of an aqueous-phase, room-temperature approach to CdS MSCs, together with an exploration of their evolution pathway. The resulting CdS MSCs display a sharp optical absorption peak at about 360 nm and are labeled MSC-360. With CdCl2 and thiourea as the respective Cd and S sources, and 3-mercarpotopropionic acid as the ligand, CdS MSC-360 develops in a mixture of a primary amine and water. We argue that the primary amine facilitates room-temperature decomposition of thiourea when CdCl2 is present, and the formation pathway of MSCs is similar to that in organic-phase approaches. Our findings show there is a viable avenue to room-temperature aqueous-phase formation of CdS MSCs. Providing explanations of the procedure developed including the formation of large aggregates, the present study represents an important advance towards a mechanistic understanding of nanocrystal synthesis.
Continuous bioactivity-dependent evolution of an antibiotic biosynthetic pathway
Authors: Johnston Chad W. , Badran Ahmed H. , Collins James J. 
Published: August 2020

AbstractAntibiotic biosynthetic gene clusters (BGCs) produce bioactive metabolites that impart a fitness advantage to their producer, providing a mechanism for natural selection. This selection drives antibiotic evolution and adapts BGCs for expression in different organisms, potentially providing clues to improve heterologous expression of antibiotics. Here, we use phage-assisted continuous evolution (PACE) to achieve bioactivity-dependent adaptation of the BGC for the antibiotic bicyclomycin (BCM), facilitating improved production in a heterologous host. This proof-of-principle study demonstrates that features of natural bioactivity-dependent evolution can be engineered to access unforeseen routes of improving metabolic pathways and product yields.
Taf14 recognizes a common motif in transcriptional machineries and facilitates their clustering by phase separation
Authors: Chen Guochao , Wang Duo , Wu Bin , Yan Fuxiang , Xue Hongjuan , Wang Quanmeng , Quan Shu , Chen Yong 
Published: August 2020

AbstractSaccharomyces cerevisiae TBP associated factor 14 (Taf14) is a well-studied transcriptional regulator that controls diverse physiological processes and that physically interacts with at least seven nuclear complexes in yeast. Despite multiple previous Taf14 structural studies, the nature of its disparate transcriptional regulatory functions remains opaque. Here, we demonstrate that the extra-terminal (ET) domain of Taf14 (Taf14ET) recognizes a common motif in multiple transcriptional coactivator proteins from several nuclear complexes, including RSC, SWI/SNF, INO80, NuA3, TFIID, and TFIIF. Moreover, we show that such partner binding promotes liquid-liquid phase separation (LLPS) of Taf14ET, in a mechanism common to YEATS-associated ET domains (e.g., AF9ET) but not Bromo-associated ET domains from BET-family proteins. Thus, beyond identifying the molecular mechanism by which Taf14ET associates with many transcriptional regulators, our study suggests that Taf14 may function as a versatile nuclear hub that orchestrates transcriptional machineries to spatiotemporally regulate diverse cellular pathways.
Adaptive self-healing electronic epineurium for chronic bidirectional neural interfaces
Authors: Song Kang-Il , Seo Hyunseon , Seong Duhwan , Kim Seunghoe , Yu Ki Jun , Kim Yu-Chan , Kim Jinseok , Kwon Seok Joon , Han Hyung-Seop , Youn Inchan , Lee Hyojin , Son Donghee 
Published: August 2020

AbstractRealizing a clinical-grade electronic medicine for peripheral nerve disorders is challenging owing to the lack of rational material design that mimics the dynamic mechanical nature of peripheral nerves. Electronic medicine should be soft and stretchable, to feasibly allow autonomous mechanical nerve adaptation. Herein, we report a new type of neural interface platform, an adaptive self-healing electronic epineurium (A-SEE), which can form compressive stress-free and strain-insensitive electronics-nerve interfaces and enable facile biofluid-resistant self-locking owing to dynamic stress relaxation and water-proof self-bonding properties of intrinsically stretchable and self-healable insulating/conducting materials, respectively. Specifically, the A-SEE does not need to be sutured or glued when implanted, thereby significantly reducing complexity and the operation time of microneurosurgery. In addition, the autonomous mechanical adaptability of the A-SEE to peripheral nerves can significantly reduce the mechanical mismatch at electronics-nerve interfaces, which minimizes nerve compression-induced immune responses and device failure. Though a small amount of Ag leaked from the A-SEE is observed in vivo (17.03 ppm after 32 weeks of implantation), we successfully achieved a bidirectional neural signal recording and stimulation in a rat sciatic nerve model for 14 weeks. In view of our materials strategy and in vivo feasibility, the mechanically adaptive self-healing neural interface would be considered a new implantable platform for a wide range application of electronic medicine for neurological disorders in the human nervous system.
Probing consequences of anion-dictated electrochemistry on the electrode/monolayer/electrolyte interfacial properties
Authors: Wong Raymond A. , Yokota Yasuyuki , Wakisaka Mitsuru , Inukai Junji , Kim Yousoo 
Published: August 2020

AbstractAltering electrochemical interfaces by using electrolyte effects or so-called “electrolyte engineering” provides a versatile means to modulate the electrochemical response. However, the long-standing challenge is going “beyond cyclic voltammetry” where electrolyte effects are interrogated from the standpoint of the interfacial properties of the electrode/electrolyte interface. Here, we employ ferrocene-terminated self-assembled monolayers as a molecular probe and investigate how the anion-dictated electrochemical responses are translated in terms of the electronic and structural properties of the electrode/monolayer/electrolyte interface. We utilise a photoelectron-based spectroelectrochemical approach that is capable of capturing “snapshots” into (1) anion dependencies of the ferrocene/ferrocenium (Fc/Fc+) redox process including ion-pairing with counter anions (Fc+–anion) caused by differences in Fc+–anion interactions and steric constraints, and (2) interfacial energetics concerning the electrostatic potential across the electrode/monolayer/electrolyte interface. Our work can be extended to provide electrolyte-related structure-property relationships in redox-active polymers and functionalised electrodes for pseudocapacitive energy storage.