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Allografts derived from live‐birth tissue obtained with donor consent have emerged as an important treatment option for wound and soft tissue repairs. Placental membrane derived from the amniotic sac consists of the amnion and chorion, the latter of which contains the trophoblast layer. For ease of cleaning and processing, these layers are often separated with or without re‐lamination and the trophoblast layer is typically discarded, both of which can negatively affect the abundance of native biological factors and make the grafts difficult to handle. Thus, a full‐thickness placental membrane that includes a fully‐intact decellularized trophoblast layer was developed for homologous clinical use as a protective barrier and scaffold in soft tissue repairs. Here, we demonstrate that this full‐thickness placental membrane is effectively decellularized while retaining native extracellular matrix (ECM) scaffold and biological factors, including the full trophoblast layer. Following processing, it is porous, biocompatible, supports cell proliferation in vitro, and retains its biomechanical strength and the ability to pass through a cannula without visible evidence of movement or damage. Finally, it was accepted as a natural scaffold in vivo with evidence of host‐cell infiltration, angiogenesis, tissue remodelling, and structural layer retention for up to 10 weeks in a murine subcutaneous implant model. [ABSTRACT FROM AUTHOR]

Understanding the evolution of brown carbon (BrC) in the atmosphere is essential for investigating its climate effects. This study deployed a novel in‐situ BrC continuous observation system to firstly measure water‐soluble BrC absorption (AbsWS‐BrC) in an offshore island over the Bohai Sea in the winter of 2020. The AbsWS‐BrC abundance before the cold wave (BCW) was more than twice higher than that after the cold wave (ACW). This was mainly ascribed to the substantially suppressed formation of secondary WS‐BrC (WS‐BrCsec). Diurnal patterns of AbsWS‐BrC exhibited nighttime peaks, which derived from enhanced primary emissions and strong aqueous‐phase processes. Photochemical processes bleached daytime WS‐BrC during BCW, while daytime peaks of WS‐BrCsec emerged during ACW due to the weakened photobleaching effect. Statistical analysis indicated ambient temperature and relative humidity as well as total oxidized nitrogen (NO2 + NO3−) and reduced nitrogen (NH4+ + NH3) were the dominant factors promoting WS‐BrCsec. Moderate aerosol pH (>2.5) also facilitated the formation of WS‐BrCsec while no obvious dependences of WS‐BrCsec on gas‐particle partitioning of ammonia, O3, and sulfur precursors were found. At the molecular level, BrC chromophores with the identified compositions, carbon oxidation state, O/C, H/C, and absorption spectra were compared between the two periods. Characteristics of water‐soluble CHO‐ and CHON‐BrC were more of secondary origin during BCW, while primary emissions contributed significantly to BrC chromophores during ACW. This study highlights the advantage of high resolution BrC measurement in probing its dynamic evolution and influencing factors. Plain Language Summary: Brown carbon (BrC) has been identified as an important short‐lived climate forcer and plays a substantial role in climate change. In this study, hourly water‐soluble BrC was measured by a novel in‐situ continuous observation system at an offshore island over the Bohai Sea. Quantitative separation of secondary versus primary water‐soluble BrC was achieved. Primary water‐soluble BrC showed nighttime peaks due to the enhanced anthropogenic emissions. The high values of secondary water‐soluble BrC in daytime depended on the relative strength of photochemical production versus photobleaching. Higher ambient temperature, relative humidity, and higher concentrations of nitrogen‐containing precursors were identified as the facilitating factors for the secondary formation of water‐soluble BrC. The high‐resolution mass spectrometry analysis provided more detailed information on the molecular compositions of BrC, which showed different characteristics before and after the cold wave. Key Points: Higher temperature, relative humidity, and oxidized/reduced nitrogen precursors promoted secondary formation of water‐soluble brown carbon (BrC)Daytime peaks of secondary water‐soluble BrC depended on the relative strength of photochemical production versus photobleachingSecondary water‐soluble BrC was strongly suppressed after the cold wave, evidenced by its molecular composition characterization [ABSTRACT FROM AUTHOR]

Non‐noble bimetallic alloys serve as an alternative catalytic material for noble metal‐based catalysts that could be applied in selective hydrogenation of unsaturated compounds. However, maintaining the catalytic stability for bimetallic nanoparticles in the selective hydrogenation process remains a substantial challenge, due to its high tendency to structural transformation upon reactive circumstances. Herein, this problem is solved by constructing carbon‐protected catalytic sites within carbon layer‐coated Ni−Fe nanoalloy composite via pyrolysis of NiFex(OH)2/glucose precursor. The optimized NiFe0.06@C catalyst exhibits excellent stability and selectivity to aminostyrene (>97 %) in the chemoselectivity hydrogenation of 3‐nitrostyrene reaction. Various characterization indicates that the enhancement in stability originates from the protective effect of the carbon layer, which prevents the oxidation and aggregation of Ni−Fe nanoparticles during the reaction process. This work greatly advances non‐noble metal‐catalyzed selective hydrogenation of nitroarenes and helps the rational design of bimetallic catalysts. [ABSTRACT FROM AUTHOR]

Amines/aminiums are recognized for their importance in new particle formation, organic nitrogen cycle, and aerosol forcings. Among the complex sources, the ocean origins and generation pathways of aminiums are less understood. During a cruise campaign over the Chinese marginal sea (Bohai Sea), five low‐molecular‐weight aminiums were measured. The strong anthropogenic period (terrestrial transport) and the weak anthropogenic period (dust, clean, and sea fog periods) were identified based on the traceable aerosol chemical species, air masses transport patterns, and marine chlorophyll‐a. Inconsistent spatiotemporal variations of various aminiums were observed. Monomethylaminium (MMAH+), dimethylaminium (DMAH+), ethylaminium (EAH+), and diethylaminium (DEAH+) were more enriched during the weak anthropogenic period than the strong anthropogenic period and especially peaked during the sea fog period. The significant correlation between the four aminiums and methanesulfonic acid suggested their secondary formation pathways. Through further exploring the governing factors, the acid–base neutralization via the aqueous phase processing was identified as a critical process for the secondary transformation of aminiums. In contrast, trimethylaminium (TMAH+) showed moderate correlation with Na+ in the total suspended particles only, suggesting its primary marine sources via enrichment in the sea‐spray aerosol through bubble bursting. Based on the step‐wise correlation analysis, the sea surface organic nitrogenous reservoir was found as the dominant contributor to the measured aminiums over the Bohai Sea, while the role of marine phytoplankton emission in the formation of aminiums was limited. Plain Language Summary: Amines have been identified as key species in the formation processes of atmospheric particles, which may further have an impact on climate change. In the marine atmosphere, amines can be emitted from the seawater, while the emission pathway and formation mechanism of different amines are still unclear. It is also ambiguous whether the main contributor of amines over the ocean is dominated by the seawater organic nitrogenous reservoir or the marine phytoplankton emission. In this study, five common particulate aminiums were measured over the Bohai Sea. All aminiums largely originated from ocean during the weak anthropogenic influence period. However, inconsistent spatiotemporal variations and different correlations with some traceable atmospheric chemical components among various aminiums indicated their different emission pathways from the seawater, including seawater bubble bursting and air–sea exchange. For those amines emitted from the latter, the acid–base neutralization in the aqueous phase was identified as a critical process for the emitted gaseous amines to be transformed into their particulate phase. Besides, we found the seawater organic nitrogen reservoir as the dominant contributor to the measured aminiums, overwhelming the influence from the marine phytoplankton emission. Key Points: Atmospheric aminiums were emitted from the ocean through different pathways, that is, sea spray and secondary formationThe acid–base neutralization via the aqueous phase processing was critical for the secondary transformation of aminiumsThe sea surface organic nitrogenous reservoir was found as the dominant contributor to the measured aminiums over the Bohai Sea [ABSTRACT FROM AUTHOR]

Recently, graph convolutional networks have shown excellent results in skeleton‐based action recognition. This paper presents a multi‐stage part‐aware graph convolutional network for the problems of model over complication, parameter redundancy and lack of long‐dependence feature information. The structure of this network has a multi‐stream input and two‐stream output, which can greatly reduce the complexity and improve the accuracy of the model without losing sequence information. The two branches of the network have the same backbone, which includes 6 multi‐order feature extraction blocks and 3 temporal attention calibration blocks, and the outputs of the two branches are fused together. In multi‐order feature extraction block, a channel‐spatial attention mechanism and a graph condensation module are proposed, which can extract more distinguishable feature and identify the relationship between parts. In temporal attention calibration block, the temporal dependencies between frames in the skeleton sequence are modeled. Experimental results show that the proposed network outperforms many mainstream methods on NTU and Kinetics datasets, for example, it achieves 92.4% accuracy on the cross‐subject benchmark of NTU‐RGBD60 dataset. [ABSTRACT FROM AUTHOR]

Sea salts act as an important medium for atmospheric processing. One intensive field campaign in the September–October period of 2019 was conducted at a subtropical coastal site over the South China Sea. Unexpected high concentrations of acidic gaseous precursors were observed, yielding high sulfate in PM2.5. Na+ ranked as the third highest inorganic species, about half of NH4+. Significant cation deficiency was found due to the ammonia‐poor environment. Diel patterns of most air pollutants from land breeze were stronger than that from marine breeze and presented pronounced unimodal distributions, which were ascribed to complex chemical processing mixed with regional transport. Thermodynamic equilibrium model (ISORROPIA II) simulation revealed sea salts could be internally mixed with fine particle secondary species and suggested evident multiphase reactions on sea salts. The simulated aerosol pH reached as low as 1.63 ± 0.50, which was related to high sulfate, insufficient alkaline species, and low aerosol liquid water content. During a continuous sea breeze episode, SO42− was underpredicted by 2.89 ± 3.85 μg m−3 if Na+ was not considered in ISORROPIA simulation. The retrieved Na+ ‐related ion pairs (NaCl, NaHSO4, and Na2SO4) accounted for about one‐fourth of the total inorganic aerosols. This study highlighted that intense atmospheric processing on sea salts occurred in fine particles and the mixing state between sea salts and other aerosol species should be considered in aerosol acidity prediction and secondary aerosol formation in coastal regions. Key Points: Sea salts were internally mixed with the secondary species even in fine particle, suggesting evident multiphase reactions on sea saltsAerosol pH was very low at the land‐sea interface and it depended on the relative strengths of sea salts versus terrestrial ammonia emissionsThe retrieved chemical forms of SO42− contained a substantial contribution from bisulfate, mainly in the form of NaHSO4 and NH4HSO4 [ABSTRACT FROM AUTHOR]

The rapid socio‐economic transformation is triggering tremendous land use transitions in China. It raises the need to explore the continuous process of land use change, which sheds light on rural revitalization. To depict the process of rural residential land use change in the transition period in China, we propose a four‐stage model of rural residential land use change and then apply the function fitting method to explore the spatial‐temporal change and type characteristics of rural residential land using a dataset of 339 cities from 2009 to 2016. We find that: (1) The change of rural residential land involves four stages—the Primary Stage (PS), the Rapid Development Stage (RDS), the Decelerated Development Stage (DDS), and the Transition Stage (TS). (2) From 2009 to 2016, 47.2% and 28.9% of the researched cities remained in RDS and DDS, respectively, and only 23.9% of the cities entered TS. (3) The high proportion of RDS cities and a significant increment of DDS cities reveal a high potential in the intensive use of rural land. These findings provide scientific guidance for land use policies, such as establishing and improving the unified land market between urban and rural areas, reinforcing the essential land management and policy implementation, and exploring the multi‐mode of comprehensive consolidation of rural residential land. [ABSTRACT FROM AUTHOR]

Mitochondria are the powerhouse of cells. They are vital organelles that maintain cellular function and metabolism. Dysfunction of mitochondria results in various diseases with a great diversity of clinical appearances. In the past, strategies have been developed for fabricating subcellular‐targeting drug‐delivery nanocarriers, enabling cellular internalization and subsequent organelle localization. Of late, innovative strategies have emerged for the smart design of multifunctional nanocarriers. Hierarchical targeting enables nanocarriers to evade and overcome various barriers encountered upon in vivo administration to reach the organelle with good bioavailability. Stimuli‐responsive nanocarriers allow controlled release of therapeutics to occur at the desired target site. Synergistic therapy can be achieved using a combination of approaches such as chemotherapy, gene and phototherapy. In this Review, we survey the field for recent developments and strategies used in the smart design of nanocarriers for mitochondria‐targeted therapeutics. Existing challenges and unexplored therapeutic opportunities are also highlighted and discussed to inspire the next generation of mitochondrial‐targeting nanotherapeutics. [ABSTRACT FROM AUTHOR]

Mitochondrien sind die Kraftwerke der Zelle. Sie sind überlebenswichtige Organellen, die zelluläre Funktionen und den Metabolismus aufrechterhalten. Eine Dysfunktion der Mitochondrien führt zu verschiedenen Krankheiten mit einer großen Diversität klinischer Erscheinungen. In der Vergangenheit wurden Strategien zur Herstellung subzellulär angreifender Nanowirkstoffcarrier entwickelt, die zunächst die zelluläre Internalisierung und schließlich die Lokalisierung der Organelle ermöglichen. Seit einiger Zeit zeichnen sich innovative Strategien für das intelligente Design multifunktionaler Nanocarrier ab. Hierarchisches Targeting erlaubt es diesen, verschiedenste Barrieren auf dem Wege der Verabreichung in vivo zu umgehen oder zu überwinden und das Organell mit guter Bioverfügbarkeit zu erreichen. Stimuli‐responsive Nanocarrier erlauben die kontrollierte Freisetzung der Therapeutika unmittelbar am gewünschten Target. Synergetische Therapien können durch die Verwendung einer Ansatzkombination erzielt werden, wie etwa aus Chemo‐, Gen‐ und Phototherapie. In diesem Aufsatz untersuchen wir dieses Feld auf neuste Entwicklungen und Strategien im intelligenten Design von Nanocarriern für Mitochondrien‐gerichtete Therapeutika. Überdies werden bestehende Herausforderungen sowie bisher unerforschte therapeutische Möglichkeiten aufgezeigt und diskutiert, um die nächste Generation mitochondrial‐gerichteter Nanotherapeutika zu inspirieren. [ABSTRACT FROM AUTHOR]

Improving the framework titanium (Ti) of titanium silicalite‐1 (TS‐1) zeolites and creating inter‐crystalline mesoporosity are two ways to enhance the catalytic properties of TS‐1 for hydroxylation of phenol. Most researches only used one of the ways. In this study, we successfully synthesized of hierarchical Titanium‐Rich (Ti‐rich) TS‐1. Ti‐rich TS‐1 was synthesized in the presence of ammonium carbonate ((NH4)2CO3). The framework Ti content of TS‐1 zeolites synthesized by different content of (NH4)2CO3 was studied by X‐ray fluorescence (XRF), Fourier transform infrared spectra (FTIR) and ultraviolet visible spectra, the framework Ti content was significantly increased by using (NH4)2CO3 as crystallization‐mediating agent. The synthesized samples were evaluated in hydroxylation of phenol. When the molar ratio of ammonium carbonate and tetraethyl orthosilicate in the synthesis gel was 0.2, the molar ratio of Si/Ti reached 34.43 and the Ti‐rich TS‐1 shows the optimum catalytic activity in hydroxylation of phenol. The post‐modification with aqueous solution of tetrapropylammonium hydroxide (TPAOH) was used to further improve the diffusion property. Compared with the parent TS‐1, the secondary pore volume was all increased. The developed hierarchical Ti‐rich TS‐1 zeolites were also assessed in hydroxylation of phenol. It was confirmed that hierarchical Ti‐rich titanium silicalite‐1 zeolites can improve the catalytic activity in phenol conversion considerably. Here, we have synthesized the hierarchical Titanium‐Rich TS‐1 zeolites using (NH4)2CO3 as a crystallization‐mediating agent and TPAOH as mesoporous structure direction. The phenol conversion, dihydroxybenzene selectivity and H2O2 efficiency were all increased compared to the conversional TS‐1 zeolites [ABSTRACT FROM AUTHOR]

ABSTRACT Purpose The sonodynamically induced anti-tumor effect of chlorin-e6 (Ce6) was studied in mice bearing hepatoma-22 solid tumors. Methods In order to determine the optimum timing of ultrasound exposure after administration of Ce6, the Ce6 concentrations in plasma, skin, muscle and tumor were estimated by measuring the fluorescence intensity of tissue extractions with a fluorescence photometer based on the standard curve. A three-dimensional optical imaging system (IVIS spectrum) was used further to characterize the distribution of Ce6 in H-22 tumor. The anti-tumor effects were estimated by measuring tumor size after sonodynamic therapy. Results Similar pharmacokinetic trends of Ce6 in mice were observed either by fluorescence spectrophotometry or by bio-optical imaging. The results also demonstrated that Ce6 has a preferential localization in tumors, but low accumulation and rapid clearance in normal tissues. The results of anti-tumor effects revealed that at an ultrasound intensity of 4 W/cm2 and a Ce6 dose of ≥10 mg/kg, a significant synergistic effect of ultrasound combined with Ce6 was observed, reducing the tumor volume significantly. Conclusion Chlorin-e6 is a potential sonosensitizer for fluorescence imaging as well as for sonodynamic therapy for cancer. The anti-tumor effect of ultrasound could be enhanced in the presence of Ce6, which might be involved in a sonochemical mechanism. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]