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Background: Platelet–cancer cell interactions modulate tumor metastasis and thrombosis in cancer. Platelet-derived extracellular vesicles (EVs) can contribute to these outcomes. Methods: We characterized the medium-sized EVs (mEVs) released by thrombin-stimulated platelets of colorectal cancer (CRC) patients and healthy subjects (HS) on the capacity to induce epithelial-mesenchymal transition (EMT)-related genes and cyclooxygenase (COX)-2(PTGS2), and thromboxane (TX)B2 production in cocultures with four colorectal cancer cell lines. Platelet-derived mEVs were assessed for their size distribution and proteomics signature. Results: The mEV population released from thrombin-activated platelets of CRC patients had a different size distribution vs. HS. Platelet-derived mEVs from CRC patients, but not from HS, upregulated EMT marker genes, such as TWIST1 and VIM, and downregulated CDH1. PTGS2 was also upregulated. In cocultures of platelet-derived mEVs with cancer cells, TXB2 generation was enhanced. The proteomics profile of mEVs released from activated platelets of CRC patients revealed that 119 proteins were downregulated and 89 upregulated vs. HS. Conclusions: We show that mEVs released from thrombin-activated platelets of CRC patients have distinct features (size distribution and proteomics cargo) vs. HS and promote prometastatic and prothrombotic phenotypes in cancer cells. The analysis of platelet-derived mEVs from CRC patients could provide valuable information for developing an appropriate treatment plan.

Despite the meteoric rise of perovskite solar cell (PSC) efficiency in recent years, commercialization of this technology is still limited by issues pertaining to perovskite instability. Herein, a novel ionic liquid (IL) – 1-ethyl-3-methylimidazolium chloride (EMIC) additive is shown to be beneficial in enhancing perovskite's ambient and operational stability. Not only does it improve crystallinity and smoothen surface topography, but the simultaneous increase in carrier lifetimes, reduction in defect density as well as improvement to interfacial band energy alignment have contributed extensively towards promoting higher power conversion efficiency (PCE) and moisture/thermal stability of the EMIC-based PCSs. The champion, unencapsulated EMIC-based PSC yields a PCE of 20.15% and retains 89% of its initial PCE after 1440 h of storage under ambient conditions (30% Relative humidity (RH), 25 °C) and retains 65% of its initial PCE after 600 h of thermal aging (85 °C, 10% RH). Energy Market Authority (EMA) Ministry of Education (MOE) National Research Foundation (NRF) The research is supported by the AcRF Tier2 grant (MOET2EP50121-0012) from the Singapore Ministry of Education, the EMAEP004-EKJGC-0003 grant from the Energy Market Authority (EMA) and National Research Foundation (NRF) Singapore, and NRF2018-ITC001- 001.

Clinical and experimental evidence sustain the role of cyclooxygenase (COX)-1 in intestinal tumorigenesis. However, the cell type expressing the enzyme involved and molecular mechanism(s) have not been clarified yet. We aimed to elucidate the role of platelet COX-1 (the target of low-dose aspirin in humans) in intestinal tumorigenesis of Apc

The versatile nature of organic conjugated materials renders their flawless integration into a diverse family of optoelectronic devices with light-harvesting, photodetection, or light-emitting capabilities. Classes of materials that offer the possibilities of two or more distinct optoelectronic functions are particularly attractive as they enable smart applications while providing the benefits of the ease of fabrication using low-cost processes. Here, we develop a novel, multi-purpose conjugated small molecule by combining boron-azadipyrromethene (aza-BODIPY) as electron acceptor with triphenylamine (TPA) as end-capping donor units. The implemented donor–acceptor–donor (D–A–D) configuration, in the form of TPA-azaBODIPY-TPA, preserves ideal charge transfer characteristics with appropriate excitation energy levels, with the additional ability to be used as either a charge transporting interlayer or light-sensing semiconducting layer in optoelectronic devices. To demonstrate its versatility, we first show that TPA-azaBODIPY-TPA can act as an excellent hole transport layer in methylammonium lead triiodide (MAPbI3)-based perovskite solar cells with measured power conversion efficiencies exceeding 17%, outperforming control solar cells with PEDOT:PSS by nearly 60%. Furthermore, the optical bandgap of 1.49 eV is shown to provide significant photodetection in the wavelength range of up to 800 nm where TPA-azaBODIPY-TPA functions as donor in near-infrared organic photodetectors (OPDs) composed of fullerene derivatives. Overall, the established versatility of TPA-azaBODIPY-TPA, combined with its robust thermal stability as well as excellent solubility and processability, provides a new guide for developing highly efficient multi-purpose electronic materials for the next-generation of smart optoelectronic devices. Ministry of Education (MOE) National Research Foundation (NRF) Published version Lam Yeng Ming would like to thank the support of the Singapore Ministry of Education Academic Research Fund Tier 2 (Grant No. MOE2019-T2-1-085). Annalisa Bruno and Enkhtur thank the National Research Foundation for the financial support (Grant No. S18-1176-SCRP). Prashant Sonar is thankful to QUT for the financial support from the Australian Research Council (ARC) for the Future Fellowship (Grant No. FT130101337) and QUT core funding (Grant No. QUT/322120-0301/07). Ajay K. Pandey acknowledges support from Australia India Strategic Research Fund (Project AISRF53820).

The rapid emergence of organic-inorganic lead halide perovskites for low-cost and high-efficiency photovoltaics promises to impact new photovoltaic concepts. Their high power conversion efficiencies, ability to coat perovskite layers on glass via various scalable deposition techniques, excellent optoelectronic properties and synthetic versatility for modulating transparency and colour, allows perovskite solar cells (PSCs) to be an ideal solution for building-integrated photovoltaics (BIPV) which transforms windows or facades into electric power generators. In this review, the unique features and properties of PSCs for BIPV application are accessed. Device engineering and optical management strategies of active layers, interlayers and electrodes for semi-transparent, bifacial and colourful PSCs are also discussed. The performance of PSCs under conditions that are relevant for BIPV such as different operational temperature, light intensity and light incident angle are also reviewed. Recent outdoor stability testing of PSCs in different countries and other demonstration of scalability and deployment of PSCs are also spotlighted. Finally, the current challenges and future opportunities for realising perovskite based BIPV are discussed. This article is protected by copyright. All rights reserved.

Hybrid metal halide perovskites exhibit well-defined semiconducting properties and efficient optoelectronic performance considering their soft crystal structure and low-energy lattice motions. The response of such a crystal lattice to light-induced charges is a fundamental question, for which experimental insight into ultrafast time scales is still sought. Here, we use infrared-activated vibrations (IRAV) of the organic components within the hybrid perovskite lattice as a sensitive probe for local structural reorganizations after photoexcitation, with femtosecond resolution. We find that the IRAV signal response shows a delayed rise of about 3 ps and subsequent decay of pronounced monomolecular character, distinguishing it from absorption associated with free carriers. We interpret our results as a two-step carrier localization process. Initially, carriers localize transiently in local energy minima formed by lattice fluctuations. A subpopulation of these can then fall into deeper trapped states over picoseconds, likely due to local reorganization of the organic molecules surrounding the carriers.

Background: The results of Aspirin prevention of colorectal adenomas in patients with familial adenomatous polyposis (FAP) are controversial. Methods: We conducted a biomarker-based clinical study in eight FAP patients treated with enteric-coated low-dose Aspirin (100 mg daily for three months) to explore whether the drug targets mainly platelet cyclooxygenase (COX)-1 or affects extraplatelet cellular sources expressing COX-isozymes and/or off-target effects in colorectal adenomas. Results: In FAP patients, low-dose Aspirin-acetylated platelet COX-1 at Serine529 (>70%) was associated with an almost complete inhibition of platelet thromboxane (TX) B2 generation ex vivo (serum TXB2). However, enhanced residual urinary 11-dehydro-TXB2 and urinary PGEM, primary metabolites of TXA2 and prostaglandin (PG)E2, respectively, were detected in association with incomplete acetylation of COX-1 in normal colorectal biopsies and adenomas. Proteomics of adenomas showed that Aspirin significantly modulated only eight proteins. The upregulation of vimentin and downregulation of HBB (hemoglobin subunit beta) distinguished two groups with high vs. low residual 11-dehydro-TXB2 levels, possibly identifying the nonresponders and responders to Aspirin. Conclusions: Although low-dose Aspirin appropriately inhibited the platelet, persistently high systemic TXA2 and PGE2 biosynthesis were found, plausibly for a marginal inhibitory effect on prostanoid biosynthesis in the colorectum. Novel chemotherapeutic strategies in FAP can involve blocking the effects of TXA2 and PGE2 signaling with receptor antagonists.

Surface imperfections created during fabrication of halide perovskite (HP) films could induce formation of various defect sites that affect device performance and stability. In this work, all-organic surface modifiers consisting of alkylammonium cations and alkanoate anions are introduced on top of the HP layer to passivate interfacial vacancies and improve moisture tolerance. Passivation using alkylammonium alkanoate does not induce formation of low-dimensional perovskites species. Instead, the organic species only passivate the perovskite's surface and grain boundaries, which results in enhanced hydrophobic character of the HP films. In terms of photovoltaic application, passivation with alkylammonium alkanoate allows significant reduction in recombination losses and enhancement of open-circuit voltage. Alongside unchanged short-circuit current density, power conversion efficiencies of more than 18.5 % can be obtained from the treated sample. Furthermore, the unencapsulated device retains 85 % of its initial PCE upon treatment, whereas the standard 3D perovskite device loses 50 % of its original PCE when both are subjected to ambient environment over 1500 h. National Research Foundation (NRF) The authors would like to acknowledge funding from the Singapore National Research Foundation through the Intra-CREATE Collaborative Grant (NRF2018-ITC001-001), Energy Innovation Research Program (NRF2015EWT-EIRP003-004, Solar CRP: S18-1176-SCRP) and the Competitive Research Program (NRF-CRP14-2014-03).

In the past few years, a large variety of perovskite solar cells (PSCs) with vivid and well-distinguished color hues have been demonstrated. In this Perspective, we compare different strategies employed to realize colorful PSCs both in opaque and semitransparent designs. The approaches used to modulate the PSCs' colorful appearance can be divided into two main categories: the first one based on the modifications of their internal layers (i.e., absorber, electron- and/or hole-transporting layers, and electrodes), while the second is based on the addition of external colored or nanostructured films to the standard PSCs. The advantages and bottlenecks of each strategy are discussed in terms of PSCs' color tunability, transparency, photovoltaic performances, fabrication processes feasibility, and scalability, in view of suitable applications in an urban context for building-integrated photovoltaics. National Research Foundation (NRF) Accepted version This research is supported by the National Research Foundation, Prime Minister’s Office, Singapore under Energy Innovation Research Program (Grant numbers: NRF2015EWT-EIRP003-004, NRF-CRP14-2014-03, Solar CRP: S18-1176-SCRP, NRF2018- ITC001-001).

In the last decade perovskite solar cells have shown remarkable improvements in power conversion efficiency which have driven the interest to commercialise the perovskite technology. Here, I will present an overview of our recent works focused on the development and the understanding of highly efficient co-evaporated perovskite solar cells with excellent thermal stability and remarkable upscalability. Our works demonstrate the compatibility of perovskite technology with consolidated industrial processes and its potential for next-generation photovoltaics on the market

Inorganic cesium lead halide perovskite nanocrystals are promising materials for optoelectronic applications as they exhibit high thermal stability alongside precise color tunability and high color purity; however, their optical properties are degraded by surface defects. This work demonstrates a room temperature synthesis of CsPbBr3 nanocrystals facilitating in situ surface passivation via the incorporation of Zn2+ cations. The facile incorporation ZnBr2 into the precursor solution facilitates Zn2+ and Br− substitution into the nanocrystal surface/subsurface layers to induce passivation of existing Pb2+ and Br– vacancies and increase the photoluminescence quantum yield from ∼48 to 86%. The XPS and solid-state 1H MAS NMR techniques show that the key modification is a reduction of the octylamine:oleic acid ratio leading to a near-neutral surface charge; this is accompanied by the appearance of larger nanosheets and nanowires observed by quantitative powder XRD and HR-TEM. The suitability of these perovskite nanocrystals for electrically driven applications was confirmed by the fabrication of light-emitting diodes, which demonstrate that the in situ Zn2+ passivation strategy enhanced the external quantum efficiency by ∼60%. National Research Foundation (NRF) PV acknowledges a Presidential Postdoctoral Fellowship from Nanyang Technological University (NTU), Singapore via grant 04INS000581C150OOE01. We acknowledge financial support from the Singapore National Research Foundation, Prime Minister’s Office, through the Competitive Research Program (CRP Award No. NRF-CRP14-2014-03). The authors would like to acknowledge the Facility for Analysis, Characterization, Testing and Simulation (FACTS) at NTU, Singapore, for use of their electron microscopy and X-ray diffraction facilities. We would also like to acknowledge the NTU Center of High Field NMR Spectroscopy and Imaging for the use of their NMR facilities. The authors would also like to thank Prof. Nripan Mathews and Dr. Nur Fadilah Jamaludin for the valuable discussion, Mr. Sai S. H. Dintakurti for discussions with aspects of the crystallographic analysis and Mr. Gautam V. Nutan for assistance with the XPS measurements. JVH acknowledges financial support for the solid state NMR instrumentation at Warwick used in this research which was funded by EPSRC (grants EP/M028186/1 and EP/K024418/1), the University of Warwick, and the Birmingham Science City AM1 and AM2 projects which were supported by Advantage West Midlands (AWM) and the European Regional Development Fund (ERDF). AAMB acknowledges the Tizard studentship from the Faculty of Engineering and Physical Sciences at University of Southampton.

Hybrid halide perovskites have achieved excellent efficiencies and remarkable performances, not just in photovoltaic cells, but also in light-emitting devices, like Light Emitting Diodes, Light Emi...

Despite the rapid development of perovskite light-emitting diodes (PeLEDs) in recent years, blue PeLEDs’ efficiencies are still inferior to those of their red and green counterparts. The poor performance is associated with, among other factors, halide segregation in bromide-chloride materials and energy funneling to lowest bandgaps in multilayered Ruddlesden–Popper (RP) systems. This study reports that compositional engineering through prudent selection of the A-site cation in a pure bromide RP system can result in a narrow distribution of layered domains. With a narrow distribution centered around the desired RP domain, efficient energy cascade to yield blue emission is ensured. Coupled with rapid nucleation induced by an antisolvent deposition technique, record efficiencies of 2.34 and 5.08%, corresponding to color-stable deep blue (∼465 nm) and cyan (∼493 nm), respectively, were attained. This composition and process engineering to design favorable structural landscape is transferrable to other material systems, which paves the way for high-performance PeLEDs. NRF (Natl Research Foundation, S’pore) MOE (Min. of Education, S’pore) Accepted version

A techno-economic analysis of perovskite-silicon tandem solar modules is presented, outlining the most viable pathway for designing cost-effective, commercially viable tandems. We explore the cost-performance trade-off for silicon bottom cells in perovskite-silicon tandems, and evaluate the potential of using low-cost, lower-efficiency silicon bottom cells, on the basis of levelized cost of electricity (LCOE), compared to the higher-efficiency, higher-cost bottom cells that have been the primary focus of most perovskite-silicon tandem research efforts. We fabricate a cost-effective four-terminal silicon-perovskite tandem using a low-cost multicrystalline bottom cell and calculate the device LCOE. We then extend this analysis by modeling performance and LCOE of similar tandems instead using high-efficiency silicon bottom cells, enabling direct comparison of a low-cost and a high-efficiency tandem. Lastly parametric analyses are performed to more broadly examine the bottom-cell cost-performance trade-off. We show that low-cost silicon, even at the detriment of efficiency, is the more likely path to make perovskite-silicon tandems commercially viable and enable future reductions in LCOE, given both current and near-future silicon technology. We lay out a clear economic motivation for pursuing low-cost silicon bottom cells in perovskite-silicon tandems, showing that they can achieve a 15–20% relative LCOE reduction compared to the single-junction sub-cells. This is a 2–3 times greater relative LCOE reduction compared with using high-efficiency silicon. Furthermore, we show that the advantage of using low-cost silicon bottom cells is robust to and benefits from expected market trends, such as falling system costs and advanced, low-cost manufacturing. This work provides a clear pathway to cost-effective tandems, outlines the benefits for existing multicrystalline silicon manufacturers to investing in tandem development, and points out a clear mismatch between commercial viability and current research efforts.

Spinel Nickel cobaltite oxide (NiCo2O4) have received great interest due to its usage in several industrial applications. The motivation of the present study is to explore the usefulness of spinel Nickel cobaltite oxide as inorganic charge transporting layer for standard perovskite solar cells (PSCs). This is the first demonstration of successful use of NiCo2O4 nanoparticles as hole transporting layer (HTL) in standard PSCs with the triple cation perovskite material. The synthesis of nanoparticles was done using a facile chemical precipitation method without the use of surfactant. The synthesized nanoparticles were characterized by the various techniques like X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), Field emission scanning electron microscopy (FE-SEM), and UV–vis spectroscopy (UV–vis). The co-ordination of Ni in Co3O4 matrix, as well as M+n O bond lengths, were confirmed by the XAS studies. The standard mesoporous PSCs were fabricated by spin-coating a thin layer of NiCo2O4 (120 nm), and fabricated PSCs show an esteemed power conversion efficiency (PCE) of >14% (under standard illumination conditions) and long-term stability (under ambient condition RH = 30–40%) as compared to the spiro-based PSCs. To improve the device performance further we also fabricated the PSCs using the interfacial hole transporting layer, presenting a PCE of >16% with almost negligible hysteresis that is comparable to the normal standard PSCs based on spiro-OMeTAD as HTL. The performance of PSCs was further analysed by Electrochemical Impedance Spectroscopy (EIS), Photoluminescence (PL), Time-resolved Photoluminescence (TrPL) studies. The results showed the reduced recombination resistance in the PSCs using NiCo2O4 as well as interfacial layer. These outcomes indicate the effectiveness of NiCo2O4 interlayer for stable and highly efficient perovskite solar cells.

Semitransparent hybrid perovskites open up applications in windows and building-integrated photovoltaics. One way to achieve semitransparency is by thinning the perovskite film, which has several benefits such as cost efficiency and reduction of lead. However, this will result in a reduced light absorbance; therefore, to compromise this loss, it is possible to incorporate plasmonic metal nanostructures, which can trap incident light and locally amplify the electromagnetic field around the resonance peaks. Here, Au nanorods (NRs), which are not detrimental for the perovskite and whose resonance peak overlaps with the perovskite band gap, are deposited on top of a thin (∼200 nm) semitransparent perovskite film. These semitransparent perovskite solar cells with 27% average visible transparency show enhancement in the open-circuit voltage (Voc) and fill factor, demonstrating 13.7% efficiency (improved by ∼6% compared to reference cells). Space-charge limited current, electrochemical impedance spectroscopy (EIS), and Mott-Schottky analyses shed more light on the trap density, nonradiative recombination, and defect density in these Au NR post-treated semitransparent perovskite solar cells. Furthermore, Au NR implementation enhances the stability of the solar cell under ambient conditions. These findings show the ability to compensate for the light harvesting of semitransparent perovskites using the plasmonic effect. National Research Foundation (NRF) This research is supported by grants from the National Research Foundation, Prime Minister’s Office, Singapore under its Campus of Research Excellence and Technological Enterprise (CREATE) program and the Solar CRP (S18-1176- SCRP).

The interfacial passivation technique is an effective method to improve the stability and photovoltaic performance of perovskite solar cells. Here, we demonstrate the importance of passivating undercoordinated halide ions in minimizing carrier losses at the perovskite/spiro-OMeTAD interface. 4-Chlorobenzene sulfonyl chloride (CBSC) has been utilized as a Lewis acid passivation material. CBSC molecules act as electron acceptors, which bind to the negatively charged undercoordinated halide ions and Pb-I antisite defects (PbI3−). The champion CBSC-passivated perovskite device shows a high power conversion efficiency (PCE) of 20.02%, unlike the pristine device with an efficiency of 18.29%. Significant long term-stability in the CBSC passivated device is also observed, maintaining 93% of the initial PCE after 768 h stored in ambient conditions with 30% relative humidity. Energy Market Authority (EMA) Ministry of Education (MOE) National Research Foundation (NRF) Published version The research is supported by an AcRF Tier2 grant (MOET2EP50121-0012) from Singapore Ministry of Education, and EMA-EP004-EKJGC-0003 grant from the Energy Market Authority (EMA) and National Research Foundation (NRF) Singapore and NRF2018-ITC001-001.

Co-evaporated perovskite solar cells have shown outstanding scalability, intrinsic stability, high efficiency and adaptability on rough surfaces. Here we present an optimal hybrid method to wide the co-evaporated MAPbI3's bandgap by a MABr treatment.

Co-evaporation of metal halide perovskites by thermal evaporation is an attractive method since it does not require harmful solvents and enables precise control of the film thickness. Furthermore, the ability to manipulate the Fermi level allows the formation of a graded homojunction, providing interesting opportunities to improve the charge carrier collection efficiency. However, little is known about how these properties affect the charge carrier dynamics. In this work, the structural and optoelectronic properties of co-evaporated MAPbI3 films varying in thickness (100, 400, and 750 nm) with a gradient in composition are analyzed. The X-ray diffraction patterns show that excess PbI2 is only present in the thick layers. From X-ray photoelectron spectroscopy depth analysis, the I/Pb atomic ratio indicates methylammonium iodide deficiencies that become more prominent with thicker films, resulting in differently n-doped regions across the thick MAPbI3 films. We suggest that due to these differently n-doped regimes, an internal electric field is formed. Side-selective time-resolved microwave photo conductivity measurements show an elongation of the charge carrier lifetimes on increasing thickness. These observations can be explained by the fact that excess carriers separate under the influence of the electric field, preventing rapid decay in the thick films.

The development of perovskite photovoltaics has so far been led by solution-based coating techniques, such as spin-coating. However, there has been an increasing interest in thermal evaporation (TE) as an industrially compatible method to fabricate perovskite solar cells (PSCs). TE has several advantages compared to solution processing, including a high degree of process control, excellent film uniformity, low material consumption, conformal substrate coverage, a lack of toxic solvents, and superb device reproducibility and scalability. These benefits make TE an ideal choice to upscale lab-scale PSCs into modules. Here, we discuss three types of TE-based perovskite deposition techniques, namely 1-step TE, multistep all-TE, and multistep hybrid of TE–gas reaction and TE–solution processing. We summarize their fundamental principles and applications, firstly on small-area PSCs and then on modules. Finally, we provide our outlook on important research topics for TE PSCs, namely device interlayers, defect passivation, and device stability. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version The authors wish to thank the National Research Foundation (NRF), Prime Minister’s Office, Singapore under the Solar Competitive Research Program (S18-1176-SCRP) and the Competitive Research Program (NRF-CRP25-2020-0004) for financial support. The authors also acknowledge T.J. Jacobsson and E. Unger’s The Perovskite Database (perovskitedatabase.com), from which a part of the data of devices discussed in this review was taken.

Hybrid metal halide perovskite solar cells (PSCs) have consistently demonstrated high power conversion efficiency (PCE), although the best performing PSCs mostly employ high-temperature (500 oC) processed compact and mesoporous TiO2. Instead, low-temperature processed PSCs are desirable for implementation on flexible substrates and tandem solar cells. Here, we present a new method to achieve high efficiency flexible planar PSCs based on a low-temperature processed nonaqueous sol-gel route synthesized TiO2 and a guanidinium iodide (GuaI) salt passivation treatment of the perovskite film. We fabricate both rigid and flexible triple-cation perovskite (Cs0.05 (MA0.17FA0.83)0.95Pb(I0.85Br0.15)3, Eg ~1.58 eV) PSCs, achieving PCEs of 19.8% and 17.0% on glass and polyethylene naphtholate, (PEN) substrates respectively. At the same time, rigid and flexible high-bandgap double cation (FA0.85Cs0.15Pb(I0.7Br0.3)3, Eg ~1.72 eV) PSCs reached a PCE of 18.0 % and of 15.8%. Moreover, large area (1cm2) ~1.58 eV and ~1.72 eV-PSCs achieved PCEs of 18.2% and 16.7% PCE on glass substrates and of 16.2% and 13.9% on PEN substrates demonstrating the high uniformity of all the solar cell layers. NRF (Natl Research Foundation, S’pore) Accepted version

Colorectal (CRC) and hepatocellular carcinoma (HCC) are associated with chronic inflammation, which plays a role in tumor development and malignant progression. An unmet medical need in these settings is the availability of sensitive and specific noninvasive biomarkers. Their use will allow surveillance of high-risk populations, early detection, and monitoring of disease progression. Moreover, the characterization of specific fingerprints of patients with nonalcoholic fatty liver disease (NAFLD) without or with nonalcoholic steatohepatitis (NASH) at the early stages of liver fibrosis is necessary. Some lines of evidence show the contribution of platelets to intestinal and liver inflammation. Thus, low-dose Aspirin, an antiplatelet agent, reduces CRC and liver cancer incidence and mortality. Aspirin also produces antifibrotic effects in NAFLD. Activated platelets can trigger chronic inflammation and tissue fibrosis via the release of soluble mediators, such as thromboxane (TX) A2 and tumor growth factor (TGF)-β, and vesicles containing genetic material (including microRNA). These platelet-derived products contribute to cyclooxygenase (COX)-2 expression and prostaglandin (PG)E2 biosynthesis by tumor microenvironment cells, such as immune and endothelial cells and fibroblasts, alongside cancer cells. Enhanced COX-2-dependent PGE2 plays a crucial role in chronic inflammation and promotes tumor progression, angiogenesis, and metastasis. Antiplatelet agents can indirectly prevent the induction of COX-2 in target cells by inhibiting platelet activation. Differently, selective COX-2 inhibitors (coxibs) block the activity of COX-2 expressed in the tumor microenvironment and cancer cells. However, coxib chemopreventive effects are hampered by the interference with cardiovascular homeostasis via the coincident inhibition of vascular COX-2-dependent prostacyclin biosynthesis, resulting in enhanced risk of atherothrombosis. A strategy to improve anti-inflammatory agents’ use in cancer prevention could be to develop tissue-specific drug delivery systems. Platelet ability to interact with tumor cells and transfer their molecular cargo can be employed to design platelet-mediated drug delivery systems to enhance the efficacy and reduce toxicity associated with anti-inflammatory agents in these settings. Another peculiarity of platelets is their capability to uptake proteins and transcripts from the circulation. Thus, cancer patient platelets show specific proteomic and transcriptomic expression profiles that could be used as biomarkers for early cancer detection and disease monitoring.

Platelet-type lipoxygenase (pl12-LOX), encoded by ALOX12, catalyzes the production of the lipid mediator 12S-hydroperoxyeicosa-5,8,10,14-tetraenoic acid (12S-HpETE), which is quickly reduced by cellular peroxidases to form 12(S)-hydroxy-5,8,10,14-eicosatetraenoic acid (12S-HETE). Platelets express high levels of pl12-LOX and generate considerable amounts of 12S-HETE from arachidonic acid (AA; C20:4, n-6). The development of sensitive chiral liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods has allowed the accurate quantification of 12S-HETE in biological samples. Moreover, advances in the knowledge of the mechanism of action of 12S-HETE have been achieved. The orphan G-protein-coupled receptor 31 (GPR31) has been identified as the high-affinity 12S-HETE receptor. Moreover, upon platelet activation, 12S-HETE is produced, and significant amounts are found esterified to membrane phospholipids (PLs), such as phosphatidylethanolamine (PE) and phosphatidylcholine (PC), promoting thrombin generation. Platelets play many roles in cancer metastasis. Among them, the platelets' ability to interact with cancer cells and transfer platelet molecules by the release of extracellular vesicles (EVs) is noteworthy. Recently, it was found that platelets induce epithelial-mesenchymal transition(EMT) in cancer cells, a phenomenon known to confer high-grade malignancy, through the transfer of pl12-LOX contained in platelet-derived EVs. These cancer cells now generate 12-HETE, considered a key modulator of cancer metastasis. Interestingly, 12-HETE was mainly found esterified in plasmalogen phospholipids of cancer cells. This review summarizes the current knowledge on the regulation and functions of pl12-LOX in platelets and cancer cells and their crosstalk.Novel approaches to preventing cancer and metastasis by the pharmacological inhibition of pl12-LOX and the internalization of mEVs are discussed.

Here we present highly efficient, large-area perovskite solar cells (PSCs) where the perovskite active layer is deposited by thermal co-evaporation. The co-evaporated MAPbI3 perovskite films are pinhole-free and uniform over several centimeters, showing low surface roughness, and a long carrier lifetime. The perovskite films’ high-quality lets the fabrication of small area PSCs (0.16 cm2) with PCEs above 20%, high reproducibility in both n.i.p and p.i.n configurations, and an impressive thermal and environmental stability over months. Similarly, the first co-evaporated mini-modules (20 cm2) achieved record PCEs above 18.%. We have also developed colored semi-transparent PSCs and mini-modules. The semi-transparent PSCs achieved PCEs consistently ~16.0% for the wide range of colors realized. Our work represents a significant step towards the development of large-area PSCs and mini-modules and the future commercialization of perovskite technology.

Recent progress of vapor-deposited perovskite solar cells (PSCs) has proved the feasibility of this deposition method in achieving promising photovoltaic devices. For the first time, it is probed the versatility of the co-evaporation process in creating perovskite layers customizable for different device architectures. A gradient of composition is created within the perovskite films by tuning the background chamber pressure during the growth process. This method leads to co-evaporated MAPbI3 film with graded Fermi levels across the thickness. Here it is proved that this growth process is beneficial for p-i-n PSCs as it can guarantee a favorable energy alignment at the charge selective interfaces. Co-evaporated p-i-n PSCs, with different hole transporting layers, consistently achieve power conversion efficiency (PCE) over 20% with a champion value of 20.6%, one of the highest reported to date. The scaled-up p-i-n PSCs, with active areas of 1 and 1.96 cm2, achieved the record PCEs of 19.1% and 17.2%, respectively, while the flexible PSCs reached a PCE of 19.3%. Unencapsulated PSCs demonstrate remarkable long-term stability, retaining ≈90% of their initial PCE when stored in ambient for 1000 h. These PSCs also preserve over 80% of their initial PCE after 500 h of thermal aging at 85 °C. © 2021 Wiley-VCH GmbH

Inflammatory bowel disease (IBD) is associated with an increased risk for thromboembolism, platelet activation, and abnormalities in platelet number and size. In colitis, platelets can extravasate into the colonic interstitium. We generated a mouse with a specific deletion of cyclooxygenase (COX)-1 in megakaryocytes/platelets [(COX-1 conditional knockout (cKO)] to clarify the role of platelet activation in the development of inflammation and fibrosis in dextran sodium sulfate (DSS)-induced colitis. The disease activity index was assessed, and colonic specimens were evaluated for histologic features of epithelial barrier damage, inflammation, and fibrosis. Cocultures of platelets and myofibroblasts were performed. We found that the specific deletion of COX-1 in platelets, which recapitulated the human pharmacodynamics of low-dose aspirin, that is, suppression of platelet thromboxane (TX)A2 production associated with substantial sparing of the systemic production of prostacyclin, resulted in milder symptoms of colitis, in the acute phase, and almost complete recovery from the disease after DSS withdrawal. Reduced colonic accumulation of macrophages and myofibroblasts and collagen deposition was found. Platelet-derived TXA2 enhanced the ability of myofibroblasts to proliferate and migrate in vitro, and these effects were prevented by platelet COX-1 inhibition or antagonism of the TXA2 receptor. Our findings allow a significant advance in the knowledge of the role of platelet-derived TXA2 in the development of colitis and fibrosis in response to intestinal damage and provide the rationale to investigate the potential efficacy of the antiplatelet agent low-dose aspirin in limiting the inflammatory response and fibrosis associated with IBD. SIGNIFICANCE STATEMENT: Inflammatory bowel disease (IBD) is characterized by the development of a chronic inflammatory response, which can lead to intestinal fibrosis for which currently there is no medical treatment. Through the generation of a mouse with specific deletion of cyclooxygenase-1 in megakaryocytes/platelets, which recapitulates the human pharmacodynamics of low-dose aspirin, we demonstrate the important role of platelet-derived thromboxane A2 in the development of experimental colitis and fibrosis, thus providing the rationale to investigate the potential efficacy of low-dose aspirin in limiting the inflammation and tissue damage associated with IBD.

The power conversion efficiency (PCE) of hole conductor free carbon-based perovskite solar cells (PSCs) is restricted by the poor charge extraction and recombination losses at the carbon-perovskite interface. For the first time we successfully demonstrated incorporation of thin layer of copper doped nickel oxide (Cu:NiOx) nanoparticles in carbon-based PSCs, which helps in improving the performance of these solar devices. Cu:NiOx nanoparticles have been synthesized by a facile chemical method, and processed into a paste for screen printing. Extensive X-ray Absorption Spectroscopy (XAS) analysis elucidates the co-ordination of Cu in a NiOx matrix and indicates the presence of around 5.4% Cu in the sample. We fabricated a monolithic perovskite module on a 100 cm2 glass substrate (active area of 70 cm2) with a thin Cu:NiOx layer (80 nm), where the champion device shows an appreciated power conversion efficiency of 12.1% under an AM 1.5G illumination. To the best of our knowledge, this is the highest reported efficiency for such a large area perovskite solar device. I-V scans show that the introduction of Cu:NiOx mesoporous scaffold increases the photocurrent, and yields fill factor (FF) values exceeding 57% due to the better interface and increased hole extraction efficiency. Electrochemical Impedance Spectroscopy (EIS) results reinforce the above results by showing the reduction in recombination resistance (Rrec) of the PSCs that incorporates Cu:NiOx interlayer. The perovskite solar modules with a Cu:NiOx layer are stable for more than 4500 h in an ambient environment (25 °C and 65% RH), with PCE degradation of less than 5% of the initial value. NRF (Natl Research Foundation, S’pore) Accepted version

MicroRNAs (miRs) are important posttranscriptional regulators of gene expression. Besides their well-characterized inhibitory effects on mRNA stability and translation, miRs can also activate gene expression. In this study, we identified a novel noncanonical function of miR-574-5p. We found that miR-574-5p acts as an RNA decoy to CUG RNA-binding protein 1 (CUGBP1) and antagonizes its function. MiR-574-5p induces microsomal prostaglandin E synthase-1 (mPGES-1) expression by preventing CUGBP1 binding to its 3'UTR, leading to an enhanced alternative splicing and generation of an mPGES-1 3'UTR isoform, increased mPGES-1 protein expression, PGE

We utilized two organic dications containing, respectively, a pyridinium and an imidazolium core to construct new n = 1 (where n refers to the number of contiguous two-dimensional (2D) inorganic layers, i.e., not separated by organic cations) 2D lead-iodide perovskites 1 and 2. The former material exhibits a (100)- and the latter a very rare 3 � 3 (110)-structural type. Compared with primary ammonium functionality, their constituent ring-centered positive charges have lower charge density. As a result, PbI 6 4- interoctahedral distortions of the inorganic lattice in 1 and 2 are reduced (Pb-I-Pb bond angles are as high as 166° and 174°, respectively). This results in bathochromically shifted optical features. In addition, the compact nature of the dications produces extremely short lead-iodide sheet separations, with respective iodide-iodide (I···I) distances as small as 4.149 and 4.278 à . These are among the shortest separations of adjacent lead-iodide layers ever reported for such materials. When crystallized as thin films on top of substrates, the resulting 2D perovskite layers do not adopt a regular growth direction parallel to the surface. Instead, the crystallites grow with no fixed orientation. As a consequence of their proximate inorganic distances and unusual crystallization tendencies, the resulting 2D perovskites exhibit low excitonic activation energies (93.59 and 96.53 meV, respectively), enhanced photoconductivity in solar cells, and unprecedented incident photon-to-current conversion rates of up to 60%. More importantly, mesoporous 2D layered perovskite solar cells with power conversion efficiencies of 1.43 and 1.83% were achieved for 1 and 2, respectively. These are the highest values obtained thus far for pure n = 1 lead-iodide perovskites and more than 20 times higher than those obtained for materials templated by more conventional cations such as phenylethylammonium (0.08%). Copyright © 2019 American Chemical Society.

Hybrid metal halide perovskites exhibit well-defined semiconducting properties and efficient optoelectronic performance considering their soft crystal structure and low-energy lattice motions. The response of such a crystal lattice to light-induced charges is a fundamental question, for which experimental insight into ultrafast time scales is still sought. Here, we use infrared-activated vibrations (IRAV) of the organic components within the hybrid perovskite lattice as a sensitive probe for local structural reorganizations after photoexcitation, with femtosecond resolution. We find that the IRAV signal response shows a delayed rise of about 3 ps and subsequent decay of pronounced monomolecular character, distinguishing it from absorption associated with free carriers. We interpret our results as a two-step carrier localization process. Initially, carriers localize transiently in local energy minima formed by lattice fluctuations. A subpopulation of these can then fall into deeper trapped states over picoseconds, likely due to local reorganization of the organic molecules surrounding the carriers.

Enhanced platelet activation has been reported in patients with essential hypertension and heart failure. The possible contribution of platelet-derived thromboxane (TX)A