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Pd-based catalysts with different Pd species (Pd ions, Pd clusters, and Pd nanoparticles) in USY were synthesized for naphthalene hydrogenation reaction. Among the catalysts, Pd clusters were prepared by controlled aggregation of Pd ions during the hydrogenation reaction with the assistance of physically adsorbed water in zeolite micropore. The coordination state and electronic structure of Pd species on these catalysts were analyzed to reveal the structure–performance relationship. Due to the high dispersion and optimized electronic structure, Pd clusters showed the highest activity for naphthalene hydrogenation compared to Pd ions and Pd nanoparticles.

The fabrication of environmentally benign, solvent‐processed, efficient, organic photovoltaic sub‐modules remains challenging due to the rapid aggregation of the current high performance non‐fullerene acceptors (NFAs). In this regard, design of new NFAs capable of achieving optimal aggregation in large‐area organic photovoltaic modules has not been realized. Here, an NFA named BTA‐HD‐Rh is synthesized with longer (hexyl‐decyl) side chains that exhibit good solubility and optimal aggregation. Interestingly, integrating a minute amount of new NFA (BTA‐HD‐Rh) into the PM6:L8‐BO system enables the improved solubility in halogen‐free solvents (o‐xylene:carbon disulfide (O‐XY:CS2)) with controlled aggregation is found. Then solar sub‐modules are fabricated at ambient condition (temperature at 25 ± 3 °C and humidity: 30–45%). Ultimately, the champion 55 cm2 sub‐modules achieve exciting efficiency of >16% in O‐XY:CS2 solvents, which is the highest PCE reported for sub‐modules. Notably, the highest efficiency of BTA‐HD‐Rh doped PM6:L8‐BO is very well correlated with high miscibility with low Flory‐Huggins parameter (0.372), well‐defined nanoscale morphology, and high charge transport. This study demonstrates that a careful choice of side chain engineering for an NFA offers fascinating features that control the overall aggregation of active layer, which results in superior sub‐module performance with environmental‐friendly solvents. A remarkable PCE of >16% is accomplished through enhanced morphology in 55 cm2 sub‐modules fabricated using environmentally benign non‐halogen solvents (O‐XY:CS2) and longer side‐chains (hexyl‐decyl) assisted new NFA (BTA‐HD‐Rh). This notable performance is attributed to an improved nano‐scale morphology, intra‐ and intermolecular interactions, lesser recombinations, and film aggregations. In addition, optimized devices have operational stabilities.

Designing and developing highly active, stable, and cost-effective hydrogen evolution reaction (HER) catalysts is crucial in the field of water electrolysis. In this study, we utilize N-doped porous carbon (CoNC) derived from zeolite imidazole metal–organic frameworks (ZIF-67) as support and prepare CoNC-Pt-IM-P via chemical impregnation (CoNC-Pt-IM) and plasma treatment. Systematic analyses reveal that calcined CoNC with pyridinic nitrogen could serve as a robust support to strongly anchor PtCo nanoclusters, while argon plasma treatment could lead to a noticeable aggregation of Co and Pt atoms so as to alter the electronic environment and enhance intrinsic HER catalytic activity. CoNC-Pt-IM-P could exhibit outstanding catalytic activity toward HER, achieving an exceptionally low overpotential of 31 mV at the current density of −10 mA cm−2 and a Tafel slope of 36 mV dec−1. At an overpotential of 50 mV, its mass activity reaches 4.90 A mgPt−1, representing enhancements of 1.5 times compared to CoNC-Pt-IM and 12.3 times compared to commercial 20 wt% Pt/C. Furthermore, it could operate stably for over 110 h at a current density of −10 mA cm−2, demonstrating its exceptional durability. This work uses plasma treatment to achieve the controllable aggregation of Co and Pt atoms to enhance their catalytic activity, which has the advantage of avoiding excessive particle aggregation compared to the commonly used method of high-temperature calcination.

Microfluidic techniques allow for the tailored construction of specific microparticles, which are becoming increasingly interesting and relevant. Here, using a microfluidic hole-plate-device and thermal-initiated free radical polymerization, submicrometer polymer particles with a highly textured surface were synthesized. Two types of monomers were applied: (1) methylmethacrylate (MMA) combined with crosslinkers and (2) divinylbenzene (DVB). Surface texture and morphology can be influenced by a series of parameters such as the monomer–crosslinker–solvent composition, surfactants, and additives. Generally, the most structured surfaces with the simultaneously most uniform particles were obtained in the DVB–toluene–nonionic-tensides system. In a second approach, poly-MMA (PMMA) particles were used to build aggregates with bigger polymer particles. For this purpose, tripropyleneglycolediacrylate (TPGDA) particles were synthesized in a microfluidic co-flow arrangement and polymerized by light- irradiation. Then, PMMA particles were assembled at their surface. In a third step, these composites were dispersed in an aqueous acrylamide–methylenebisacrylamide solution, which again was run through a co-flow-device and photopolymerized. As such, entities consisting of particles of three different size ranges—typically 0.7/30/600 µm—were obtained. The particles synthesized by both approaches are potentially suitable for loading with or incorporation of analytic probes or catalysts such as dyes or metals.

Strategies to achieve controlled nanoparticle aggregation have gained much interest, due to the versatility of such systems and their applications in materials science and medicine. In this article we demonstrate that coiled-coil peptide-induced aggregation based on electrostatic interactions is highly sensitive to the length of the peptide as well as the number of presented charges. The quaternary structure of the peptide was found to play an important role in aggregation kinetics. Furthermore, we show that the presence of peptide fibers leads to well-defined nanoparticle assembly on the surface of these macrostructures.

: A common challenge of drug loading and delivery using magnetic resonance imaging (MRI) contrast agents (CAs) is the tendency of aggregation and precipitation at high drug loading conditions. Herein, we propose a generic strategy of controlled ideal aggregation (CIA) to restrict the tendency. : Fe , β-Lapachone (LAP), brequinar (BQR), or Sorafenib (SOR) was respectively loaded onto Gd poly (acrylic acid) macrochelate (GP), an MRI CA, in the hollow core of nitrite-modified hollow mesoporous organosilica nanoparticles (HMON-SNO). The aggregation of FeGP, LAPGP, BQRGP, and SORGP was controlled to be ideal without precipitation by the fixed space of the HMON-SNO hollow core. The sizes of the ideal aggregates are larger than the mesopore size of HMON-SNO, which prevents premature drug leakage and release. : After the accumulation of FeGP@HMON-SNO in tumors, the presence of glutathione (GSH) in the tumor microenvironment (TME) triggers the HMON-SNO degradation to release NO, Fe and GP. The released Fe reacts with endogenous hydrogen peroxide (H O ) to generate Fe and hydroxyl radical ( OH). The -SNO groups on the surface of HMON-SNO react with GSH, enabling sustained NO generation. The elevated NO level induces mitochondrial dysfunction, down-regulates lipid droplets through the alleviation of hypoxia and consequently promotes the accumulation of lipid peroxidation (LPO) under excess OH to induce tumor cell ferroptosis. Moreover, the released GP facilitates high contrast -weighted MRI of tumors due to its high value, enabling real-time monitoring for the delivery of FeGP@HMON-SNO. : The proposed strategy of CIA with universality was successfully utilized to restrict the aggregation of MRI CAs at high drug loading conditions. The developed FeGP@HMON-SNO with eminent drug loading content were used for tumor ferroptosis-gas synergistic therapy with high efficacy.

By using N,N -dimethylformamide (DMF) as a solvent and reducing agent, and polyurethane (PU) as a structure-directing agent, flexible silver nanochains are formed under mild conditions with mean diameter of 15.97 and 35.6 nm, respectively. Some linear chain-like aggregates of silver nanoparticles with mean diameter of 6.69 nm are also formed by controlling the experimental condition. In parallel experiment, silver nanospheres with mean diameters of 5.76 nm, instead of nanochains are generated when antioxidants are added. After 3 days of aging, some nano clusters are transformed into triangular or hexagonal nanoplates. This aggregation behavior was characterized by UV–Vis spectroscopy, TEM, and powder X-ray diffraction. The aggregation mechanism of silver nanoparticles in the PU and ATPU was discussed. Our results provide potential application for new generation of nanodevice.

This chapter contains sections titled: Introduction Metal Enhanced Fluorescence Near‐Infrared Metal Enhanced Fluorescence Advantages Near‐Infrared MEF on Silver Island Films Colloid Coated Surfaces Nanoparticle Interactions Increase Fluorescence Enhancements Limits of Detection Dynamic Range Conclusions Acknowledgements

A one-dose-fits-all approach to use of aspirin has yielded only modest benefits in long-term prevention of cardiovascular events, possibly due to underdosing in patients of large body size and excess dosing in patients of small body size, which might also affect other outcomes. Using individual patient data, we analysed the modifying effects of bodyweight (10 kg bands) and height (10 cm bands) on the effects of low doses (≤100 mg) and higher doses (300–325 mg or ≥500 mg) of aspirin in randomised trials of aspirin in primary prevention of cardiovascular events. We stratified the findings by age, sex, and vascular risk factors, and validated them in trials of aspirin in secondary prevention of stroke. Additionally, we assessed whether any weight or height dependence was evident for the effect of aspirin on 20-year risk of colorectal cancer or any in-trial cancer. Among ten eligible trials of aspirin in primary prevention (including 117 279 participants), bodyweight varied four-fold and trial median weight ranged from 60·0 kg to 81·2 kg (p<0·0001). The ability of 75–100 mg aspirin to reduce cardiovascular events decreased with increasing weight (pinteraction=0·0072), with benefit seen in people weighing 50–69 kg (hazard ratio [HR] 0·75 [95% CI 0·65–0·85]) but not in those weighing 70 kg or more (0·95 [0·86–1·04]; 1·09 [0·93–1·29] for vascular death). Furthermore, the case fatality of a first cardiovascular event was increased by low-dose aspirin in people weighing 70 kg or more (odds ratio 1·33 [95% CI 1·08–1·64], p=0·0082). Higher doses of aspirin (≥325 mg) had the opposite interaction with bodyweight (difference pinteraction=0·0013), reducing cardiovascular events only at higher weight (pinteraction=0·017). Findings were similar in men and women, in people with diabetes, in trials of aspirin in secondary prevention, and in relation to height (pinteraction=0·0025 for cardiovascular events). Aspirin-mediated reductions in long-term risk of colorectal cancer were also weight dependent (pinteraction=0·038). Stratification by body size also revealed harms due to excess dosing: risk of sudden death was increased by aspirin in people at low weight for dose (pinteraction=0·0018) and risk of all-cause death was increased in people weighing less than 50 kg who were receiving 75–100 mg aspirin (HR 1·52 [95% CI 1·04–2·21], p=0·031). In participants aged 70 years or older, the 3-year risk of cancer was also increased by aspirin (1·20 [1·03–1·47], p=0·02), particularly in those weighing less than 70 kg (1·31 [1·07–1·61], p=0·009) and consequently in women (1·44 [1·11–1·87], p=0·0069). Low doses of aspirin (75–100 mg) were only effective in preventing vascular events in patients weighing less than 70 kg, and had no benefit in the 80% of men and nearly 50% of all women weighing 70 kg or more. By contrast, higher doses of aspirin were only effective in patients weighing 70 kg or more. Given that aspirin's effects on other outcomes, including cancer, also showed interactions with body size, a one-dose-fits-all approach to aspirin is unlikely to be optimal, and a more tailored strategy is required. Wellcome Trust and National Institute for Health Research Oxford Biomedical Research Centre.

Proton-pump inhibitors (PPIs) are often prescribed in combination with thienopyridines. Conflicting data exist as to whether PPIs diminish the efficacy of clopidogrel. We assessed the association between PPI use, measures of platelet function, and clinical outcomes for patients treated with clopidogrel or prasugrel. In the PRINCIPLE-TIMI 44 trial, the primary outcome was inhibition of platelet aggregation at 6 h assessed by light-transmission aggregometry. In the TRITON-TIMI 38 trial, the primary endpoint was the composite of cardiovascular death, myocardial infarction, or stroke. In both studies, PPI use was at physician's discretion. We used a multivariable Cox model with propensity score to assess the association of PPI use with clinical outcomes. In the PRINCIPLE-TIMI 44 trial, 201 patients undergoing elective percutaneous coronary intervention were randomly assigned to prasugrel (n=102) or high-dose clopidogrel (n=99). Mean inhibition of platelet aggregation was significantly lower for patients on a PPI than for those not on a PPI at 6 h after a 600 mg clopidogrel loading dose (23·2±19·5%vs 35·2±20·9%, p=0·02), whereas a more modest difference was seen with and without a PPI after a 60 mg loading dose of prasugrel (69·6±13·5%vs 76·7±12·4%, p=0·054). In the TRITON-TIMI 38 trial, 13 608 patients with an acute coronary syndrome were randomly assigned to prasugrel (n=6813) or clopidogrel (n=6795). In this study, 33% (n=4529) of patients were on a PPI at randomisation. No association existed between PPI use and risk of the primary endpoint for patients treated with clopidogrel (adjusted hazard ratio [HR] 0·94, 95% CI 0·80–1·11) or prasugrel (1·00, 0·84–1·20). The current findings do not support the need to avoid concomitant use of PPIs, when clinically indicated, in patients receiving clopidogrel or prasugrel. Daiichi Sankyo Company Limited and Eli Lilly and Company sponsored the trials. This analysis had no funding.