A Single-Cell Atlas of Bovine Skeletal Muscle Reveals Mechanisms Regulating Intramuscular Adipogenesis and Fibrogenesis

Background Intramuscular fat (IMF) and intramuscular connective tissue (IMC) are often seen in human myopathies and are central to beef quality. The mechanisms regulating their accumulation remain poorly understood. Here, we explored the possibility of using beef cattle as a novel model for mechanistic studies of intramuscular adipogenesis and fibrogenesis. Methods Skeletal muscle single-cell RNAseq was performed on three cattle breeds, including Wagyu (high IMF), Brahman (abundant IMC but scarce IMF), and Wagyu/Brahman cross. Sophisticated bioinformatics analyses, including clustering analysis, gene set enrichment analyses, gene regulatory network construction, RNA velocity, pseudotime analysis, and cell-cell communication analysis, were performed to elucidate heterogeneities and differentiation processes of individual cell types and differences between cattle breeds. Experiments were conducted to validate the function and specificity of identified key regulatory and marker genes. Integrated analysis with multiple published human and non-human primate datasets was performed to identify common mechanisms. Results A total of 32 708 cells and 21 clusters were identified, including fibro/adipogenic progenitor (FAP) and other resident and infiltrating cell types. We identified an endomysial adipogenic FAP subpopulation enriched for COL4A1 and CFD (log2FC = 3.19 and 1.92, respectively; P \u3c 0.0001) and a perimysial fibrogenic FAP subpopulation enriched for COL1A1 and POSTN (log2FC = 1.83 and 0.87, respectively; P \u3c 0.0001), both of which were likely derived from an unspecified subpopulation. Further analysis revealed more progressed adipogenic programming of Wagyu FAPs and more advanced fibrogenic programming of Brahman FAPs. Mechanistically, NAB2 drives CFD expression, which in turn promotes adipogenesis. CFD expression in FAPs of young cattle before the onset of intramuscular adipogenesis was predictive of IMF contents in adulthood (R2 = 0.885, P \u3c 0.01). Similar adipogenic and fibrogenic FAPs were identified in humans and monkeys. In aged humans with metabolic syndrome and progressed Duchenne muscular dystrophy (DMD) patients, increased CFD expression was observed (P \u3c 0.05 and P \u3c 0.0001, respectively), which was positively correlated with adipogenic marker expression, including ADIPOQ (R2 = 0.303, P \u3c 0.01; and R2 = 0.348, P \u3c 0.01, respectively). The specificity of Postn/POSTN as a fibrogenic FAP marker was validated using a lineage-tracing mouse line. POSTN expression was elevated in Brahman FAPs (P \u3c 0.0001) and DMD patients (P \u3c 0.01) but not in aged humans. Strong interactions between vascular cells and FAPs were also identified. Conclusions Our study demonstrates the feasibility of beef cattle as a model for studying IMF and IMC. We illustrate the FAP programming during intramuscular adipogenesis and fibrogenesis and reveal the reliability of CFD as a predictor and biomarker of IMF accumulation in cattle and humans

Interface-Assisted Perovskite Modulations for High-Performance Light-Emitting Diodes

Metal halide perovskites have emerged as a class of promising materials for a wide range of optoelectronic devices. Compared with traditional inorganic and organic semiconductors, perovskite materials can be easily processed via solution-based techniques at low temperatures and exhibit high photo-luminescence efficiency, outstanding colour purity, and superior charge transport properties, showing great promise for cost-effective and high-performance light-emitting diodes (LEDs). Since the first demonstration of room-temperature operating perovskite-based LEDs (PeLEDs) in 2014, various useful strategies on optimizing perovskite emissive materials and device structures have been developed, leading to notably enhanced device performance of PeLEDs during the last several years. Nevertheless, despite rapid progress in improving the external quantum efficiencies (EQEs) of PeLEDs, which are now approaching those of commercialized technologies, the operational stability of state-of-the-art PeLEDs remains poor, presenting a critical challenge for their practical applications and commercialization. Besides, a majority of the optimization strategies demonstrated for PeLEDs derivate from those developed for either perovskite photovoltaics or prevailing light-emitting technologies, e.g., organic- and quantum-dot-based LEDs. Although these strategies are helpful, more comprehensive investigations and in-depth understanding of factors affecting the property of perovskite emissive layers and the device performance of ensuing PeLEDs are highly desirable to foster further advancements of this promising technology. In this thesis, we focus our study on near-infrared PeLEDs based on triiodide perovskite emissive layers processed from precursor solutions. We systematically investigate the critical effects of precursors, substrates, and additives on the film quality of perovskite emissive layers. With the indepth understanding of the perovskite crystallization process, we developed a range of effective interface-assisted strategies on modulating the perovskite emissive layers, which enable us to achieve PeLEDs with high EQEs and excellent long-term operational stability beyond the state-of-the-art.In the first study, we unveiled the synergistic effect of precursor stoichiometry and interfacial reactions for PeLEDs. We reveal that ZnO efficiently deprotonates the organic cations, which promotes the formation of highly emissive perovskites from precursor solution with excess organic components, leading to the achievement of PeLEDs with a high EQE of 19.6 %. In the second study, we presented that such ZnO deprotonation process of excess organic cations can also assist the cation exchange process between cesium-formamidinium (FA-Cs) cation exchange, enabling low-temperature fabrication of pure-phase Cs-FA mixed cation perovskite films with widely tunable emissions peaking between 715 nm and 800 nm as well as high-performance devices with peak EQEs over 15%. In spite of enhanced device efficiency realized by the perovskite crystallization modulation, this ZnO deprotonation process places a detrimental effect on the stability of the PeLEDs, which can be accelerated by Joule heating and high electric fields during the device operation. In the third study, we, therefore, demonstrated the role of ZnO in catalyzing an efficient amidation reaction between incorporated dicarboxylic acid additives and excess FAI, preventing the above-mentioned harmful interfacial reaction. With this strategy, the operational half lifetime of the resulting PeLEDs was improved to 682 hours at 20 mA/cm2 while maintaining a high device efficiency of 18.6%. In the last work, we emphasized that the rational design of molecular reactions between two additives (diamine and triacrylate) and perovskite components with the assistance of ZnO substrates can subsequently eliminate the negative effect introduced by additive, reduce the defect density and enhance the crystal orientation in the perovskite emissive layers. The rational understanding of interfacial interactions between perovskite, additives, and ZnO, enabled us to achieve PeLEDs with a device efficiency of 23.8% as well as an outstanding operational stability T70 (reduction to 70% of initial efficiency) lifetime of 290 hours at 20 mA/cm2. The study in this thesis developed effective interface-assisted modulation strategies for high-quality perovskites towards highly efficient and stable PeLEDs for commercialization. A thorough understanding of perovskite chemistry-property-performance modulation assisted by interfaces is indispensable for the future development of PeLEDs and our study took an important step.Metall-halid-perovskiter har visat sig vara en lovande kategori av material för en bred variation av optoelektroniska komponenter med utmärkt prestanda. Jämfört med traditionella oorganiska och organiska halvledare kan perovskit-material enkelt tillverkas och bearbetas med hjälp av lösningsbaserade tekniker vid låga temperaturer samtidigt som de visar hög fotoluminescenseffektivitet, enastående färgrenhet och överlägsna egenskaper gällande laddningstransport. Metall-halidperovskiter uppvisar därmed stora fördelar för att kunna uppnå kostnadseffektiva och högpresterande lysdioder (LED:er). De första perovskit-baserade lysdioderna (PeLED:er) som kunde drivas under rumstemperaturförhållanden visades upp år 2014. Sedan dess har en rad användbara strategier utvecklats för att optimera de ljusemitterande perovskitmaterialen såväl som diodstrukturerna, vilket lett till märkbart förbättrad prestanda för PeLEDs. Trots snabba framsteg gällandes förbättringen av PeLED:ernas externa kvanteffektivitet, som nu närmar sig kommersiell teknik, är den operativa stabiliteten hos vetenskapens bästa PeLED:er fortfarande dålig, och utgör ett avgörande hinder och en utmaning för att nå praktiska tillämpningar och kommersialisering. En majoritet av de optimeringsstrategier som använts för PeLEDs kommer antingen från strategier som utvecklats för perovskit-solceller eller nuvarande ljusemitterande teknik, t.ex. organiska och kvantprickbaserade lysdioder (OLEDs och QLEDs). Även om dessa strategier är hjälpsamma, så är omfattande undersökningar och djupgående förståelse av faktorer som påverkar egenskaper hos det emitterande perovskitlagret och prestandan av kommande PeLED:er mycket önskvärd för att främja ytterligare framsteg av denna lovande teknik. I denna avhandling fokuserar vi vår studie på nära infraröda peLED:er baserade på emitterande trijodid-perovskitfilmer tillverkade från prekursorlösningar. Vi undersöker systematiskt de avgörande effekterna som prekursorer, substrat och tillsatser har på filmkvaliteten hos de emitterande perovskitfilmerna. Med den djupgående förståelsen av perovskitkristalliseringsprocessen utvecklade vi en rad användbara gränsyteassisterade strategier för att modulera de emitterande perovskitfilmerna. Detta gör det möjligt för oss att uppnå PeLED:er med integrerade höga EQE:er och utmärkt långsiktig operativ stabilitet som är bättre än dagens bästa PeLED:er. I den första studien visar vi på den nyckelroll som det alkaliska ZnO-mellanlagret har gällandes påverkan av kristalliseringen av perovskiter, så väl som det stökiometriska förhållandet i prekursorlösningarna. ZnO kan enkelt deprotonera organiska katjoner och eliminera överskottet av FAI, vilket bidrar till en effektiv fasövergång från prekursorkomplex till rena perovskiter med hög emissivitet vilket leder till hög-effektivitets-dioder på 19,6 %. I uppföljningsstudien visade vi att ZnO-deprotonerings-processen av överskott av organiska katjoner också kan initiera; Cs-FA katjonutbyte, förändra legeringsförhållandt mellan Cs och FA, bilda ren-fas-Cs-FA-perovskitfilmer med justerbara emissionstoppar mellan 715 nm och 800 nm samt EQE-värden över 15% för de bästa dioderna. Trots den förbättrade effektivitet som uppnås genom perovskitkristalliseringsmoduleringen, bildar denna ZnO-deprotoneringsprocess en skadlig effekt på PeLED:ernas stabilitet. En sådan effekt kan påskyndas av Joule-uppvärmning och hög elektrisk fältstyrka under drift. I den tredje studien visade vi ZnOkatalysatorernas viktiga roll när det gäller att införa en effektiv amidiseringsreaktion mellan dikarboxylsyra-tillsatser och överskotts-FAI, vilket förhindrar ovannämnda skadliga gränsytereaktion. Med denna strategi förbättrades peLED:ers operativa halveringstid till nästan 700 timmar vid 20 mA/cm2 samtidigt som en hög effektivitet på 18,6% uppehålls. I det sista arbetet visade vi att kombinationen av två tillsatsämnen (diamin och triakrylat) kan förbättra interaktionerna mellan perovskit och tillsatser avsevärt, tillexempel via tvärbindning av tillsatser och omvandling av överskott av FAI till stabila stora molekyler med hjälp av ZnO-katalysatorer. På detta vis uppnår vi flera funktioner, alltifrån passivering av defekter till perovskitkristallorienteringsreglering. Den rationella förståelsen av gränsyte-interaktioner mellan perovskit, tillsatser och ZnO, gjorde det möjligt för oss att uppnå PeLED:er med en effektivitet på 23,8% samt en enastående driftsstabilitet, med en T70 livslängd på 290 timmar (med en minskning till 70% av den ursprungliga effektiviteten). Studien som presenteras i denna avhandling visar på en effektiv strategi för att åstadkomma högeffektiva och stabila PeLED:er för framtida kommersialisering. En omfattande förståelse av kemi-struktur-egenskap-prestanda-modulering av perovskiter som assisteras av gränsytor är oumbärlig för utvecklingen av PeLED:er, och vår studie tog ett viktigt steg för den förståelsen

Dithiol treatments enhancing the efficiency of hybrid solar cells based on PTB7 and CdSe nanorods

We report the fabrication of polymer/inorganic hybrid solar cells (HSCs) based on CdSe nanorods (NRs) and the semiconducting polymer PTB7. The power conversion efficiency of HSCs can be significantly enhanced by engineering the polymer/nanocrystal interface with ethanedithiol (EDT) and 1,4-benzenedithiol (1,4-BDT) treatments and reached 2.58% and 2.79%, respectively. These results were preferable to that of a pyridine-coated NR-based device (1.75%). This improvement was attributed to the thiol groups of EDT and 1,4-BDT, which can tightly coordinate the Cd ions to form Cd-thialate on CdSe NR surfaces, thereby effectively passivating the NR surface and reducing the active layer defects. Therefore, the rate of exciton generation and dissociation was enhanced and led to the improvement of the device performance

Chlorobenzene vapor assistant annealing method for fabricating high quality perovskite films

In this study, chlorobenzene (CB) vapor assistant annealing (VAA) method is employed to make high quality perovskite films and produce high efficiency CH3NH3PbI3-xClx perovskite solar cells. The perovskite films made by this method present several advantages such as increased crystallinity, large grain size and reduced crystal boundaries compared with those prepared by thermal annealing (TA) method, which is beneficial to charge dissociation and transport in hybrid photovoltaic device. In addition, it is found that the CB VAA method could improve the surface property of perovskite film, resulting in a preferable coverage of PCBM layer and a better interfacial contact between perovskite film and upper PCBM film. Consequently, the short circuit current density (J(SC)) of the devices is significantly increased, yielding a high efficiency of 14.79% and an average efficiency of 13.40%, which is 13% higher than that of thermal annealed ones. This work not only put forward a simple and efficient approach to prepare highly efficient perovskite solar cells but also provide a new idea to improve the morphology and interfacial contact in one integration step. (C) 2016 Elsevier B.V. All rights reserved

Electrical tuning of radiative cooling at ambient conditions

Passive radiative cooling forms a sustainable means for cooling of objects through thermal radiation. Along with progress on static cooling systems, there is an emerging need for dynamic control to enable thermoregulation. Here, we demonstrate temperature regu-lation of devices at ambient pressure and temperature by electri-cally tuning their radiative cooling power. Our concept exploits the possibility to electrochemically tune the thermal emissivity and thereby cooling power of a conducting polymer, which enabled reversible control of device temperatures of around 0.25 degrees C at ambient conditions in a sky simulator. Besides tuneable radiative cooling by exposure to the sky, the concept could also contribute to reduced needs for indoor climate control by enabling dynamic control of thermal energy flows between indoor objects, such as be-tween people and walls.Funding Agencies|Knut and Alice Wallenberg Foundation; Linkoping University; Wallenberg Wood Science Center; Swedish government; Strategic Research Area in Materials Science on Functional Materials at Linkoping University (faculty grant SFO-Mat-LiU) [2009 00971]; Swedish Armed Forces Research; Swedish Research Council [2020-00287]; Wallenberg Academy [2019.0163]</p

Multicolor light emission in manganese-based metal halide composites

Manganese-based organic-inorganic metal halide composites have been considered as promising candidates for lead-free emitters. However, in spite of their excellent luminescence properties in green and red regions, blue emission-a critical component for white light generation-from pristine manganese-based composites is currently missing. In this work, we successfully achieve blue luminescence center in manganese-based composites through selecting specific organic component methylbenzylamine (MBA). Our approach is fundamentally different from green and red emission in manganese-based composites, which result from manganese-halide frameworks. The coexistence of different luminescence centers in our manganese-based composites is confirmed by photoluminescence (PL) and photoluminescence excitation (PLE) results. As a result of different photoluminescence excitation responses of different emission centers, the resulting emission color can be tuned with selecting different excitation wavelengths. Specifically, a white light emission can be obtained with Commission Internationale de leclairage coordinates of (0.33, 0.35) upon the 330 nm excitation. We further demonstrate the promise of our manganese-based composites in the anti-counterfeiting technology and multicolor lighting. Our results provide a novel strategy for full-spectral emission in manganese-based organic-inorganic metal halide composites and lay a solid foundation for a range of new applications. (C) 2022 Author(s).Funding Agencies|Knut and Alice Wallenberg Foundation [Dnr KAW 2019.0082]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoeping University [2009-00971]; China Scholarship Council (CSC)</p

Quantum random number generation based on a perovskite light emitting diode

True random number generation is not thought to be possible using a classical approach but by instead exploiting quantum mechanics genuine randomness can be achieved. Here, the authors demonstrate a certified quantum random number generation using a metal-halide perovskite light emitting diode as a source of weak coherent polarisation states randomly producing an output of either 0 or 1. The recent development of perovskite light emitting diodes (PeLEDs) has the potential to revolutionize the fields of optical communication and lighting devices, due to their simplicity of fabrication and outstanding optical properties. Here we demonstrate that PeLEDs can also be used in the field of quantum technologies by implementing a highly-secure quantum random number generator (QRNG). Modern QRNGs that certify their privacy are posed to replace classical random number generators in applications such as encryption and gambling, and therefore need to be cheap, fast and with integration capabilities. Using a compact metal-halide PeLED source, we generate random numbers, which are certified to be secure against an eavesdropper, following the quantum measurement-device-independent scenario. The obtained generation rate of more than 10 Mbit s(-1), which is already comparable to commercial devices, shows that PeLEDs can work as high-quality light sources for quantum information tasks, thus opening up future applications in quantum technologies.Funding: CENIIT Linkouml;ping University; Swedish Research Council [2017-04470]; QuantERA grant SECRET [2019-00392]; Knut and Alice Wallenberg Foundation through the Wallenberg Centre for Quantum Technology (WACQT); ERC Starting Grant [717026]; Wallenberg Academy Fellowship; Fondo Nacional de Desarrollo Cientifico y Tecnologico (FONDECYT) [1200859]; ANID-Millennium Science Initiative Program [ICN17_012]; Linkoeping University</p

Inverted polymer solar cells with enhanced fill factor by inserting the potassium stearate interfacial modification layer

A thin potassium stearate (KSt) film combined with an optimized ZnO film was introduced to improve the fill factor (FF) of highly efficient inverted polymer solar cells (PSCs). Atomic force microscopy and contact angle measurements were used to show that the introduction of KSt did not change the morphology of interlayer. On the contrary, it is beneficial for the spread of the active layer on the interlayer. The origin of enhanced FF was systematically studied by the ideal current-voltage model for a single heterojunction solar cell and electrochemical impedance spectroscopy. On the basis of the data analysis, the reduced charge recombination loss was responsible for this improved FF. At last, when KSt was replaced by sodium stearate (NaSt), the similar experiment phenomenon was observed. This indicates that inserting a metallic stearate modified layer is a promising strategy to enhance inverted PSCs performance. Published by AIP Publishing

Improving the efficiency of inverted organic solar cells by introducing ferrocenedicarboxylic acid between an ITO/ZnO interlayer

In this study, ferrocenedicarboxylic acid (FDA) has been introduced between an ITO electrode and ZnO interlayer to improve the performance of inverted polymer solar cells. The highest power conversion efficiency (PCE) of 9.06% is achieved among the measurements. Besides, the average PCE of FDA/ZnO based devices is observed with 11.9% enhancement (8.73% vs. 7.80%) compared to ZnO-only devices. Electrical characterization, surface morphology, wetting properties, as well as exciton generation rate and dissociation probability were investigated to understand the impact of FDA insertion on the interfacial properties. It was found that exciton dissociation efficiency and charge collection efficiency were significantly improved after inserting FDA, while the surface morphology, average roughness and water contact angle of the ZnO film were not changed. It was thought that FDA connected to the ITO electrode and ZnO film because of its carboxyl groups, which lead to a compact interfacial contact and reduced charge recombination. In addition, the devices based on the FDA/ZnO interlayers displayed improved stability in the argon-filled glove box without any encapsulation for about 1000 h compared to the ZnO-only devices. This study provides a new idea to introduce materials with functional groups between ITO/metal oxides interfaces to achieve more efficient charge collection and device performance

Interface-assisted cation exchange enables high-performance perovskiteLEDs with tunable near-infrared emissions

Achieving high-quality cesium-formamidinium lead iodide (CsxFA1_xPbI3) perovskites with tunable band gaps is highly desired for optoelectronic applications including solar cells and light -emit-ting diodes (LEDs). Herein, by utilizing an alkaline-interface-assisted cation-exchange method, we fabricate highly emissive CsxFA1_x PbI3 perovskite films with fine-tunable Cs-FA alloying ratio for emis-sion-tunable near-infrared (NIR) LEDs. We reveal that the deproto-nation of FA+ cations and the formation of hydrogen-bonded gels consisting of CsI and FA facilitated by the zinc oxide underneath effectively removes the Cs-FA ion-exchange barrier, promoting the formation of phase-pure CsxFA1_xPbI3 films with tunable emis-sions filling the gap between that of pure Cs-and FA-based perov-skites. The obtained NIR perovskite LEDs (PeLEDs) peaking from 715 to 780 nm simultaneously demonstrate high peak external quantum efficiencies of over 15%, maximum radiances exceeding 300 W sr_1 m_2, and high power conversion efficiencies above 10% at 100 mA cm_2, representing the best-performing LEDs based on solution-processed NIR emitters in a similar region.Funding Agencies|ERC Starting Grant [717026]; Swedish Research Council Vetenskapsra [2020-03564]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]; Swedish Research Council [2020-00589]</p