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The management of hypertrophic scars (HSs), characterized by excessive collagen production, involves various nonsurgical and surgical interventions. However, the absence of a well‐defined molecular mechanism governing hypertrophic scarring has led to less‐than‐ideal results in clinical antifibrotic treatments. Therefore, our study focused on the role of decorin (DCN) and its regulatory role in the TGF‐β/Smad signalling pathway in the development of HSs. In our research, we observed a decrease in DCN expression within hypertrophic scar tissue and its derived cells (HSFc) compared to that in normal tissue. Then, the inhibitory effect of DCN on collagen synthesis was confirmed in Fc and HSFc via the detection of fibrosis markers such as COL‐1 and COL‐3 after the overexpression and knockdown of DCN. Moreover, functional assessments revealed that DCN suppresses the proliferation, migration and invasion of HSFc. We discovered that DCN significantly inhibits the TGF‐β1/Smad3 pathway by suppressing TGF‐β1 expression, as well as the formation and phosphorylation of Smad3. This finding suggested that DCN regulates the synthesis of collagen‐based extracellular matrix and fibrosis through the TGF‐β1/Smad3 pathway. [ABSTRACT FROM AUTHOR]

Mercerization had been widely used in the textile industry because of its simplicity and ability to improve the luster, strength, and dyeing properties of cotton fabrics. However, the water transfer behavior of mercerized cotton fabrics had not been systematically investigated. In this work, cotton fabrics were treated with different concentrations of alkali (130 and 260 g/L) for structural characterization (scanning electron microscopy [SEM], Fourier transform infrared [FTIR]), water absorption (vertical wicking height), moisture absorption (moisture return rate), water retention, and so forth, and were compared with industrial mercerized cotton. It meant that water absorbency and water holding capacity of mercerized cotton textiles were improved by reducing surface impurity, increasing amorphous region, and increasing the number of free hydroxyl groups. It was easier for water molecules to move through the fabric as the vertical wicking height increased. Research showed that the water absorption and water transfer properties of cotton fabrics were related to the alkali concentration in the mercerized treatment, and a comparison with industrial mercerized cotton also proved this point. It also showed that the amount of tension had an effect on water transfer in the fabric, which provided further precision in regulating the mercerization process, improving the thermal comfort of mercerized fabrics, and achieving the aim of regulating the mercerization process according to market demand and environmental influences. [ABSTRACT FROM AUTHOR]

Continuous monitoring of arterial blood pressure is clinically important for diagnosing and managing cardiovascular diseases. Soft electronic devices with skin‐like properties show promise in various applications, including the human‐machine interface, the Internet of Things, and health monitoring. Herein, the use of add‐on soft electronic interfaces addresses the connection challenges between soft electrodes and rigid data acquisition circuitry for bioimpedance monitoring of cardiac signals, including heart rate and cuffless blood pressure is reported. Nanocomposite films in add‐on electrodes provide robust electrical and mechanical contact with the skin and the rigid circuitry. Bioimpedance sensors composed of add‐on electrodes offer continuous blood pressure monitoring with high accuracy. Specifically, the bioimpedance collected with add‐on nanocomposite electrodes shows a signal‐to‐noise ratio of 37.0 dB, higher than the ratio of 25.9 dB obtained with standard silver/silver chloride (Ag/AgCl) gel electrodes. Although the sample set is low, the continuously measured systolic and diastolic blood pressure offer accuracy of −2.0 ± 6.3 mmHg and −4.3 ± 3.9 mmHg, respectively, confirming the grade A performance based on the IEEE standard. These results show promise in bioimpedance measurements with add‐on soft electrodes for cuffless blood pressure monitoring. [ABSTRACT FROM AUTHOR]

Multifunctional nanoaggregates are widely used in cancer phototheranostics. However, it is challenging to construct their multifunctionality with a single component, and deliver them rapidly and efficiently without complex modifications. Herein, a NIR‐absorbing small molecule named TBT‐2(TP‐DPA) is designed and certify its theranostic potentials. Then, their nanoaggregates, which are simply encapsulated by DSPE‐PEG, demonstrate a photothermal efficiency of 51% while keeping a high photoluminescence quantum yield in the NIR region. Moreover, the nanoaggregates can be excited and delivered by an 808 nm pulse laser to solid tumors within only 40 min. The delivery efficiency and theranostic efficacy are better than that of the traditional enhanced permeability and retention (EPR) effect (generally longer than 24 hours). This platform is first termed as the photoinduced thermoacoustic (PTA) process, and confirm its application requires both NIR‐responsive materials and pulse laser irradiation. This study not only inspires the design of multifunctional nanoaggregates, but also offers a feasible approach to their fast delivery. The platform reported here provides a promising prospect to boost the development of multifunctional theranostic drugs and maximize the efficacy of used medicines for their clinical applications. [ABSTRACT FROM AUTHOR]

Hybrid supercapacitors use electric double‐layer capacitance and Faradaic pseudocapacitance as energy storage mechanisms. This type of supercapacitor is becoming a prime candidate for next‐generation energy storage devices, with advantages in terms of energy density, specific capacitance, and life cycle. However, reducing the electrode area and increasing the specific capacitance of hybrid supercapacitors remain challenging. In this study, a MoCl5 Precursor‐assisted Ultrafast Laser Carbonization (MPAULC) method to fabricate symmetric hybrid supercapacitors with improved capacitance and reduced size is proposed. The method uses an ultrafast laser to induce the formation of carbon/MoO3 composite with the assistance of the MoCl5 precursor. This ultrafast laser carbonization method exhibited high processing precision. The role of the precursor in laser processing is studied using time‐resolved imaging and temperature calculations. The specific area capacitance of the C/MoO3 hybrid supercapacitor is 11.85 mF cm−2, 9.2 times higher than that of the laser‐induced carbon supercapacitor without precursor. The MPAULC method provides a reliable pathway for fabricating miniaturized hybrid supercapacitors with carbon/metal oxide composite electrodes on polymer substrates. [ABSTRACT FROM AUTHOR]

Perovskite materials are widely used in the fields of luminescence and light energy conversion with the advantages of low cost and outstanding optoelectronic properties. However, abundant surface lattice defects heavily affect the performances of perovskite optoelectronic devices. Here, by treating surface defects with oleylamine molecules in situ, the surface trap states are significantly decreased in a CsPbBr3 microplate, enabling photoluminescence intensity and carrier lifetimes to be dramatically enhanced and prolonged, respectively. These interesting phenomena can be attributed to the binding of undercoordinated Pb atoms with N atoms on the surface of perovskite microplate. The strong binding energy of lead‐halogen bonds inhibits the photodegraded reactions of the crystal, leading to the significant improvement of luminescent stability for the microplate correspondingly. The results not only provide experimental guidance for passivating lattice defects but also pave the way for improving the efficiency of wide materials and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Hybrid lead halide perovskites are widely studied in photodetectors due to their excellent optoelectronic properties. However, most of the perovskite photodetectors require an external power source, which adds additional costs and limits their application. Here, a self‐powered photodetector based on the heterojunction formed by methylammonium lead tribromide perovskite nanocrystals (MAPbBr3 NCs) and mesoporous TiO2 (m‐TiO2) is demonstrated by a space‐confined growth method. The NCs are uniformly grown on the m‐TiO2 framework and mirco‐heterojunctions are formed. Systematic research shows that the built‐in electric field of the mirco‐heterojunctions increases the exciton dissociation and carrier transport. In the absence of an external power supply, the photodetectors display an impressive on/off ratio (>105) and high detectivity (>1011 Jones) under 100 mW cm−2 solar irradiation. In addition, the winning device shows excellent long‐term stability (photocurrent maintains over 92% after exposure of 102 days to the air), benefiting from the enhanced binding energy and reduced defect density of NCs. It is believed that this study sheds light on the further development of self‐powered perovskite‐based photodetectors with high performance. [ABSTRACT FROM AUTHOR]

Manipulating photocarrier dynamics for luminescent materials is fundamentally important for steering luminescent properties of optoelectronic devices. Here, interfacial engineering is realized by constructing Au NPs‐CsPbBr3 interfaces toward resonant coupling between localized surface plasmon and exciton. Through ultrafast laser spectroscopic measurements, it is demonstrated that photoluminance originating from CsPbBr3 excitonic recombination is significantly enhanced at the interface with prolonged lifetimes. Interfacial photocarrier dynamics are mediated by plasmon‐induced hot electron transfer (PHET) and plasmon‐induced resonant energy transfer (PIRET) processes. By simply varying excitation laser wavelengths, PHET path of photocarriers is actively switched on and off. The results are of great significance for actively manipulating photocarrier dynamics of perovskite luminescent devices. [ABSTRACT FROM AUTHOR]

Self‐powered photodetectors (SPPDs) are generally carried out in multilayered heterostructures with different semiconductors or in Schottky junctions with different metal electrodes. It is interesting to build an SPPD using metal–semiconductor–metal (MSM) structures with the same type of metal electrodes. Here, an SPPD is fabricated facilely by stacking a piece of irregular InSe nanosheet on a pair of Au electrodes with asymmetric van der Waals contacts. The SPPD performs a high responsivity of 0.103 A W−1, a high on‐off current ratio over 104, a high detectivity of 1.83 × 1010 Jones, a fast response time of 1 ms and a broadband sensing spectrum ranging from 300 to 1000 nm under zero bias. A series of characterization and working mechanism analysis demonstrate the contribution of the asymmetric Schottky barrier heights and contact geometries in Au–InSe junctions to the self‐powered performance of the detector. This work offers an effective scheme to construct high‐performance SPPDs in simple architecture and processing for potential optoelectronic device applications. [ABSTRACT FROM AUTHOR]

We introduce a new perfect sampling technique that can be applied to general Gibbs distributions and runs in linear time if the correlation decays faster than the neighborhood growth. In particular, in graphs with subexponential neighborhood growth like ℤd, our algorithm achieves linear running time as long as Gibbs sampling is rapidly mixing. As concrete applications, we obtain the currently best perfect samplers for colorings and for monomer‐dimer models in such graphs. [ABSTRACT FROM AUTHOR]

Obesity and insulin resistance are significant contributors to hypertension. There is a high prevalence of obesity among Uyghurs in the rural areas of Xinjiang, China. Therefore, this study aimed to explore the association between insulin resistance indices and hypertension according to different body weights in rural Uyghur residents of Xinjiang, China. A total of 12 813 local Uyghur residents were recruited for the study. Excluding those with incomplete data and those using antihypertensive, lipid‐lowering, or glycemic drugs, 9577 permanent residents were eligible for the study. Three insulin resistance indicators were calculated: triglyceride to high‐density lipoprotein cholesterol ratio, product of fasting triglyceride and glucose (TYG), and metabolic score for insulin resistance. Multivariate logistic regression analysis was performed to estimate the association between the three non‐insulin‐based insulin resistance indices and the risk of hypertension for different body weights. TYG was significantly associated with hypertension in the normal‐weight group, particularly in women. In the obese group that was obese, all three indicators were associated with hypertension. Since TYG was associated with hypertension in the groups with normal weight and obesity, it may be useful as a reference indicator for insulin resistance. This indicator may provide a basis for the identification and management of hypertension risk among adults in the Uyghur population. [ABSTRACT FROM AUTHOR]

Precise drug delivery for internal organs is always an important clinical issue. In this study, we developed a dual‐wavelength optical resolution photoacoustic laparoscope, and achieved precise and efficient delivery of nanomedicine to multiple abdominal organs. The laparoscope integrated 532 and 820 nm light to map the vascular network, and visually deliver the nanoparticles to the targeted area using photoacoustic radiation force, respectively. To achieve endoscopic use, we employed a micro‐electro‐mechanical‐system (MEMS) scanner to realize internal two‐dimensional raster scanning of the optical beams. Using phantom experiments, the lateral resolutions were measured as 3.75 μm for 532 nm, and 5.25 μm for 820 nm, respectively. Besides, we demonstrated the feasibility of targeted drug delivery using mouse‐ear tumor model, normal organs, and colon tumor model. All the experimental results suggested that this strategy can serve as a promising precise drug delivery method for the effective treatment of internal organ diseases. [ABSTRACT FROM AUTHOR]

Purpose: The polymorphism of methylenetetrahydrofolate reductase (MTHFR) gene C677T has been linked to H‐type hypertension. But the conclusion remained controversial. To elucidate this issue, we performed a comprehensive meta‐analysis to analyze the MTHFR C677T polymorphism and H‐type hypertension. Materials and methods: The English and Chinese databases were systematically searched to identify relevant studies until November 2020. RevMan 5.3 and Stata 12.0 software were used for meta‐analysis. The odds ratio (ORs) and 95% confidence intervals (95% CIs) were used to assess the relationship between the MTHFR C677T polymorphism and H‐type hypertension. Results: A total of 14 studies involving 1769 cases and 1443 controls were included. The meta‐analysis results showed the association between MTHFR C677T polymorphism and H‐type hypertension with the homozygous codominant model (OR = 3.30, 95% CI = 1.94–5.60), heterozygous codominant model (OR = 2.34, 95% CI = 1.53–3.58), dominant model (OR = 1.79, 95% CI = 1.33–2.41), recessive model (OR = 2.70, 95% CI = 1.73–4.21),and the allelic model (OR = 1.82, 95% CI = 1.41–2.35). All p‐values were less than 0.05. Therefore, MTHFR C677T polymorphism has a positive correlation with the risk of H‐type hypertension. Among them, TT mutation has the greatest impact on the activity of this enzyme, which causes Hcy to rise and leads to H‐type hypertension. Conclusion: In summary, our results provide sufficient data to support the hypothesis that the MTHFR C677T polymorphism is related to H‐type hypertension susceptibility. [ABSTRACT FROM AUTHOR]

It is generally considered that photoacoustic imaging (PAI) and fluorescence imaging (FLI) cannot be enhanced concurrently, as they are dependent on competitive photophysical processes at the single‐molecule level. Herein, we reveal that BDTR9‐OC8 and BDTR9‐C8, which have identical π‐conjugated backbones but are substituted by side chains of different rigidity, show distinct phototheranostic properties in the aggregated state. The NIR‐II FLI and PAI brightness of BDTR9‐C8 nanoparticles are enhanced by 4.6 and 1.4 times compared with BDTR9‐OC8 nanoparticles. Theoretical calculations and GIWAXS analysis revealed that BDTR9‐C8 with rigid side chains shows a relative amorphous condensed state, which will benefit the efficient transportation of photo‐generated excitons and phonons, subsequently enhancing the FLI and PAI signals. Besides, both nanoparticles exhibit excellent photothermal conversion efficiency due to their strong light‐harvesting capability and are considered effective photothermal therapy materials. This work provides an illuminating strategy for material design in the future. [ABSTRACT FROM AUTHOR]

Both treatment and postoperative evaluation of cancer play vital roles in improving the survival rate of patients. However, existing cancer therapies face multiple challenges of low drug delivery efficiency, separation of treatment and evaluation, and lack of noninvasive, routine and cost‐efficient postoperative monitoring methods. To overcome these issues, an all‐in‐one anti‐cancer strategy is proposed by using the combination of the photoacoustic (PA) effect and polymer nanoparticles. This strategy shows enhanced nanoparticles delivery, significant tumor ablation, and the capability of non‐invasive and longitudinal postoperative evaluation. Near‐infrared (NIR) excited photoacoustic radiation force (PAF) based on the high optical absorption nanoparticles opens the vascular barrier, accumulates the nanoparticles inside the tumor, and enables visualization of real‐time nanoparticles distribution. Instead of conventional thermal therapy by using a continuous wave laser, the NIR pulsed laser coupled with PAF offers thermal therapy with further positive accumulation of nanoparticles, and significantly improves the treatment efficiency in return. In addition, the endogenous hemoglobin enables PA imaging to evaluate the efficacy of tumor therapy and monitor the progress of postoperative tumors in vivo through structural and functional parameters of the vascular network. This study presents a new opportunity for formulation of personalized and accurate tumor therapy, and timely feedback of therapeutic effect. [ABSTRACT FROM AUTHOR]

Neuroimaging techniques can reveal complex brain functions associated with behaviors and emotions. However, most existing neuroimaging methods suffer from balancing tradeoffs among the temporal and spatial resolutions as well as the field of view (FOV). A high spatiotemporal resolution photoacoustic neuroimaging (PANI) technique with a wide FOV sufficient to cover the entire mouse cerebral cortex in transverse plane and measure fast neuronal dynamics is developed. Based on the experimental validations from both drug‐induced epilepsy and electrical stimulation in the mouse brain, PANI features the following capabilities: i) deriving functional information from the fluctuation of total hemoglobin (HbT) to identify the neural activity and connectivity of the mouse cortex; ii) integrating with other neurological recording methods such as electroencephalograph (EEG) to investigate the neurovascular coupling; and iii) revealing the interactive connectivity between distant brain regions under different physiological conditions. The special features of PANI offer a unique window on investigating the fast neural dynamics with a wide FOV at the capillary scale. [ABSTRACT FROM AUTHOR]

Flexible electronic technologies have broad development prospects. Fabrication of micro devices on flexible carbon precursors via laser carbonizing has the advantages of involving only one step, requiring no mask, and wide adaptability. It has attracted significant attention in recent years to fabricate micro devices on polyimide (PI) via laser carbonization. However, the precision of laser carbonization is low because large areas of the material are easily carbonized simultaneously. Thus, the fabrication of micro devices with high precision and narrow line widths via laser carbonization remains challenging. Herein, a laser‐induced carbonization method with point‐to‐line carbonization strategy is proposed and used to fabricate supercapacitors on PI. The carbon line width decreases from over 150 to below 10 µm using this method. High‐precision conductive writing is realized on PI. Carbon lines written by this method have low resistance and porous surface. Hence, these carbon structures are suitable as electrodes for supercapacitors. Supercapacitors with microscale electrode widths are fabricated using this method. This work demonstrates that the point‐to‐line strategy improves the precision of laser carbonization and provides an effective method for fabricating flexible electronics on polymers with high precision. [ABSTRACT FROM AUTHOR]

Precise and efficient delivery of nanomedicine to the target site has remained as a major roadblock in advanced cancer treatment. Here, a novel photoacoustic force (PAF)‐guided nanotherapeutic system is reported based on a near‐infrared (NIR)‐absorbing semiconducting polymer (SP), showing significantly improved tumor accumulation and deep tissue penetration for enhanced phototherapeutic efficacy. The accumulation of nanoparticles in 4T1 tumor‐bearing mice induced by the PAF strategy displays a fivefold enhancement in comparison with that of the traditional passive targeting pathway, in a significantly shortened time (45 min vs 24 h) with an enhanced penetration depth in tumors. Additionally, a tumor‐bearing mouse model is rationally designed to unveil the mechanism, indicating that the nanoparticles enter solid tumors through enhanced transportation across blood vessel barriers via both inter‐endothelial gaps and active trans‐endothelial pathways. This process is specifically driven by PAF generated from the nanoparticles under NIR laser irradiation. The study thus demonstrates a new nanotherapeutic strategy with low dose, enhanced delivery efficiency in tumor, and boosted therapeutic efficacy, opening new doors for designing novel nanocarriers. [ABSTRACT FROM AUTHOR]

Endoscopy has been widely used in biomedical imaging and integrated with various optical and acoustic imaging modalities. Photoacoustic imaging (PAI), one of the fastest growing biomedical imaging modalities, is a noninvasive and nonionizing method that owns rich optical contrast, deep acoustic penetration depth, multiscale and multiparametric imaging capability. Hence, it is preferred to miniaturize the volume of PAI and develop an emerged endoscopic imaging modality referred to as photoacoustic endoscopy (PAE). It has been developed for more than one decade since the first report of PAE. Unfortunately, until now, there is no mature photoacoustic endoscopic technique recognized in clinic due to various technical limitations. To address this concern, recent development of new scanning mechanisms, adoption of novel optical/acoustic devices, utilization of superior computation methods and exploration of multimodality strategies have significantly promoted the progress of PAE toward clinic. In this review, we comprehensively reviewed recent progresses in single‐ and multimodality PAE with new physics, mechanisms and strategies to achieve practical devices for potential applicable scenarios including esophageal, gastrointestinal, urogenital and intravascular imaging. We ended this review with challenges and prospects for future development of PAE. [ABSTRACT FROM AUTHOR]

We sharpen run‐time analysis for algorithms under the partial rejection sampling framework. Our method yields improved bounds for: the cluster‐popping algorithm for approximating all‐terminal network reliability; the cycle‐popping algorithm for sampling rooted spanning trees; and the sink‐popping algorithm for sampling sink‐free orientations. In all three applications, our bounds are not only tight in order, but also optimal in30 constants. [ABSTRACT FROM AUTHOR]

The Lengshuikeng Ag‐Pb‐Zn ore field is located in the North Wuyi Mesozoic volcanic belt south of the Qinzhou–Hangzhou suture zone between the Yangtze and Cathaysia paleo‐plates. Previous zircon U–Pb geochronological studies on ignimbrites and tuffs from this area have yielded conflicting ages of 157–161 Ma (Early Upper Jurassic) and 137–144 Ma (Early Lower Cretaceous). Volcanic rocks in the ore field have even been proposed to include both ages. Our SHRIMP zircon U–Pb dating of the ignimbrite and tuff samples from the ore field, along with field observations and results from geochronological work on other volcanic and sub‐volcanic rocks in the region, shows that two populations of magmatic zircons, one autocrystic and the other xenocrystic, are present in the pyroclastic rocks. The autocrystic zircons have ages suggesting formation/eruption at approximately 140 Ma, whereas the xenocrystic zircons give ages of 155–159 Ma, indicating intrusion of granitic porphyries in the Early Upper Jurassic. Therefore, the pyroclastic rocks in the Lengshuikeng Ag–Pb–Zn ore field formed in the Early Lower Cretaceous. The youngest zircon U–Pb ages from pyroclastic rocks may not represent the formation/eruption ages of the host rock, depending most likely on the existence and/or abundance of juvenile or vitric pyroclasts in the rocks. [ABSTRACT FROM AUTHOR]

To overcome the current limitations of chemodynamic therapy (CDT), a Mo2C‐derived polyoxometalate (POM) is readily synthesized as a new CDT agent. It permits synergistic chemodynamic and photothermal therapy operating in the second near‐infrared (NIR‐II) biological transparent window for deep tissue penetration. POM aggregated in an acidic tumor micro‐environment (TME) whereby enables specific tumor targeting. In addition to the strong ability to produce singlet oxygen (1O2) presumably via Russell mechanism, its excellent photothermal conversion enhances the CDT effect, offers additional tumor ablation modality, and permits NIR‐II photoacoustic imaging. Benefitting from the reversible redox property of molybdenum, the theranostics based on POM can escape from the antioxidant defense system. Moreover, combining the specific responsiveness to TME and localized laser irradiation, side‐effects shall be largely avoided. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Thiopeptides, arising from complex posttranslational modifications of a genetically encoded precursor peptide, are of great interest due to their structural complexity and important biological activities. All of these antibiotics share a macrocyclic peptidyl core that contains a central, six‐membered nitrogen heterocycle and are classified into five series a—e based on the oxidation state of the central nitrogenous ring. Here, we report that the biosynthesis of the central piperidine heterocycle of series a thiopeptides relies on the activity of homologues of an F420H2‐dependent reductase TppX4 by exploiting and characterizing the piperidine‐containing thiopeptin biosynthetic gene (tpp) cluster in Streptomyces tateyamensis. In vitro reconstruction of TppX4 activity demonstrated that the piperidine heterocycle of thiopeptins was transformed from a dehydropiperidine heterocycle, and TppX4 tolerated the changes in the C‐termini and macrocyclic peptidyl core of substrate and also tolerated dehyropiperidine‐containing monocyclic or bicyclic thiopeptides. The identification of TppX4 and its substrate tolerance enriches the biosynthetic toolbox for development of additional thiopeptide analogs for clinical drug screening. [ABSTRACT FROM AUTHOR]

Brain imaging is an important technique in cognitive neuroscience. In this article, we designed a stereotaxic‐apparatus‐compatible photoacoustic microscope for the studies of rat cortical hemodynamics. Compared with existing optical resolution photoacoustic microscopy (ORPAM) systems, the probe owns feature of fast, light and miniature. In this microscope, we integrated a miniaturized ultrasound transducer with a center frequency of 10 MHz to detect photoacoustic signals and a 2‐dimensional (2D) microelectromechanical system (MEMS) scanner to achieve raster scanning of the optical focus. Based on phantom evaluation, this imaging probe has a high lateral resolution of 3.8 μm and an effective imaging domain of 2 × 2 mm2. Different from conventional ORPAMs, combining with standard stereotaxic apparatus enables broad studies of rodent brains without any motion artifact. To show its capability, we successfully captured red blood cell flow in the capillary, monitored the vascular changes during bleeding and blood infusion and visualized cortical hemodynamics induced by middle cerebral artery occlusion. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: In this paper, two kinds of commonly used vegetable carbon black (VCB, 3000 mesh; nano) at 50 g kg−1 concentration (based on dried gelatin) were added to 48 g kg−1 of fish gelatin (GEL) solutions and their effects on mechanical, barrier and anti‐photooxidation properties of GEL films were investigated. RESULTS: From the SEM images, it was shown that compared with 3000 mesh VCB (1–2 μm), nano VCB (100–200 nm) made the microstructure of GEL film more compact and more gelatin chains were cross‐linked by nano VCB. The addition of nano VCB significantly increased gelatin film strength with the greatest tensile strength of 52.589 MPa and stiffness with the highest Young's modulus of 968.874 MPa, but led to the reduction of film elongation. Also, the VCB presence significantly improved water vapour and oxygen barrier properties of GEL film. Importantly, nano VCB increased GEL film with better UV barrier property due to its stronger UV absorption nature when compared with micron VCB. This property could help in the preservation of oil samples in the photooxidation accelerated test. CONCLUSION: With improved properties, the nano VCB‐reinforced GEL film may have great potential for application in the edible packaging field, especially for the anti‐photooxidation property. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Photoacoustic microscopy (PAM) provides a fundamentally new tool for a broad range of studies of biological structures and functions. However, the use of PAM has been largely limited to small vertebrates due to the large size/weight and the inconvenience of the equipment. Here, we describe a portable optical‐resolution photoacoustic microscopy (pORPAM) system for 3‐dimensional (3D) imaging of small‐to‐large rodents and humans with a high spatiotemporal resolution and a large field of view. We show extensive applications of pORPAM to multiscale animals including mice and rabbits. In addition, we image the 3D vascular networks of human lips, and demonstrate the feasibility of pORPAM to observe the recovery process of oral ulcer and cancer‐associated capillary loops in human oral cavities. This technology is promising for broad biomedical studies from fundamental biology to clinical diseases. [ABSTRACT FROM AUTHOR]

Abstract: Background: Studies on risk preferences have long been of great concern and have examined the neural basis underlying risk‐based decision making. However, studies using conventional transcranial direct current stimulation (tDCS) revealed that bilateral stimulation could change risk propensity with limited evidence of precisely focalized unilateral high‐definition transcranial direct current stimulation (HD‐tDCS). The aim of this experiment was to investigate the effect of HD‐tDCS focalizing the left dorsal lateral prefrontal cortex (DLPFC) on risk‐taking behavior during the Balloon Analogue Risk Task (BART). Methods: This study was designed as a between‐subject, single‐blind, sham‐controlled experiment. University students were randomly assigned to three groups: the anodal group (F3 anode, AF3, F1, F5, FC3 returned), the cathodal group (F3 cathodal, AF3, F1, F5, FC3 returned) and the sham group. Subsequently, 1.5‐mA 20‐min HD‐tDCS was applied during the BART, and the Positive Affect and Negative Affect Scale (PANAS), the Sensation Seeking Scale‐5 (SSS‐5), and the Behavioral Inhibition System and Behavioral Approach System scale (BIS/BAS) were measured as control variables. Results: The cathodal group earned less total money than the sham group, and no significant difference was observed between the anodal group and the sham group. Conclusions: These results showed that, to some extent, focalized unilateral cathodal HD‐tDCS on left DLPFC could change performance during risky tasks and diminish risky decision making. Further studies are needed to investigate the dose effect and electrode distribution of HD‐tDCS during risky tasks and examine synchronous brain activity to show the neural basis. [ABSTRACT FROM AUTHOR]

ABSTRACT To develop high performances of polymer composite laminates, differential scanning calorimetry and dynamic rheological analysis studies were conducted to show curing behaviors of 3-aminophenoxyphthalonitrile/epoxy resin (3-APN/EP) matrix and define cure parameters of manufacturing processes. Glass fiber reinforced 3-APN/EP (GF/3-APN/EP) composite laminates were successfully prepared through different processing conditions with three parameters such as pressures, temperatures, and time. Based on flexure tests, dynamic mechanical analysis, thermal gravimetric analysis, and scanning electron microscope, the complementary catalytic effect of the three processing parameters is investigated by studying mechanical behavior, thermomechanical behavior, thermal behavior, and fracture morphology of GF/3-APN/EP laminates. The 50/50 GF/3-APN/EP laminates showed a significant improvement in flexural strength, glass transition temperature ( Tg), and thermal stability with favorable processing parameters. It was also found that the Tg and thermal stability were significantly improved by the postheated treatment method. The effect of manufacturing process provides a new and simple route for the polymer-matrix composites application, which indicates that the composites can be manufactured at low temperatures. But, they can be used in a high temperature environment. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39746. [ABSTRACT FROM AUTHOR]

A series of bisphenol A (BPA)-based 2,2-bis-[4-(3,4-dicyanophenoxy)phenyl]propane (BAPh) prepolymers and polymers were prepared using BPA as a novel curing agent. Ultraviolet-visible and Fourier transform infrared spectroscopy spectrum were used to study the polymerization reaction mechanism of the BAPh/BPA polymers. The curing behaviors were studied by differential scanning calorimetry and dynamic rheological analysis, the results indicated that the BAPh/BPA prepolymers exhibit large processing windows (109.5-148.5°C) and low complex viscosity (0.1-1 Pa·s) at moderate temperature, respectively. Additionally, the BAPh/BPA/glass fiber (GF) composite laminates were manufactured and investigated. The flexural strength and modulus of the composite laminates are 548.7-632.8 MPa and 25.7-33.2 GPa, respectively. The thermal stabilities of BAPh/BPA/GF composite laminates were studied by thermogravimetry analysis. The temperatures at 5% weight loss ( T5%) of the composite laminates are 508.5-528.7°C in nitrogen and 508.1-543.2°C in air. In conclusion, the BAPh/BPA systems can be used as superior matrix materials for numerous advanced composite applications. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

A series of copolymers and glass fiber composites were successfully prepared from 2,2-bis [4-(3,4-dicyanophenoxy) phenyl] propane (BAPh), epoxy resins E-44 (EP), and polyarylene ether nitriles (PEN) with 4,4′-diaminodiphenyl sulfone as curing additive. The gelation time was shortened from 25 min to 4 min when PEN content was 0 wt % and 15 wt %, respectively. PEN could accelerate the crosslinking reaction between the phthalonitrile and epoxy. The initial decomposition temperatures ( Ti) of BAPh/EP copolymers and glass fiber composites were all more than 350°C in nitrogen. The Tg of 15 wt % PEN glass fiber composites increased by 21.2°C compared with that of in comparison with BAPh/EP glass fiber composite. The flexural strength of the copolymers and glass fiber composites reached 119.8 MPa and 698.5 MPa which increased by 16.6 MPa and 127.3 MPa in comparison with BAPh/EP composite, respectively. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Poly(arylene ether nitrile) (PEN) nanocomposites filled with functionalized graphite nanoplates (GNs) were prepared by a simple solution- casting method and then characterized by rheometer and thermogravimetric analysis (TGA). This study investigates how the surface treatment of GNs affects the GN dispersion state. The linear rheological test indicated that the 4-aminophenoxyphthalonitrile-grafted GN (GN-CN) presented better dispersion in PEN matrix than purified GN because the corresponding composite showed the lower rheological percolation threshold, which was further confirmed by scanning electron microscopy and solution experiments. The TGA revealed that the presence of 4-aminophenoxyphthalonitrile-grafted GN retarded the depolymerization evidently compared with that of purified GN, showing remarkable increase in the temperatures corresponding to a weight loss of 5 wt % (increased by 21°C) and maximum rate of decomposition (increased by 9°C). Both the dispersion state and the surface functionalization of GN are very important to the thermal stability of PEN matrix. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Bisphthalonitrile (BAPh) monomer was blended with novolac resins to achieve good processing resin blends. The curing behaviors of the novolac/BAPh (novolac/BAPh) blends were studied by differential scanning calorimetry (DSC) and dynamic rheological analysis. The results indicated that the blends had large processing windows (98-118°C), and they can copolymerize without any other curing additives. The novolac/BAPh copolymers were obtained by short curing times and low curing temperatures. Thermal and thermal-oxidative stabilities of the copolymers were investigated by thermal gravimetric analysis, and the char yields up to 74 and 35% by weight at 800°C were achieved under nitrogen and air atmosphere, respectively. These postcured copolymers exhibited a 5% weight loss temperature of 502°C in air. These results revealed that the copolymers exhibited excellent thermal and thermal-oxidative stabilities. Dynamic mechanical properties of the copolymers were systematically evaluated by dynamic mechanical analysis. The copolymers exhibited higher glass transition temperatures ( Tg) as the BAPh content increased. Mechanical properties of the copolymers were investigated, and these data showed that flexural strength and flexural modulus of the 50 : 50 novolac/BAPh copolymers were 91 MPa and 5.78 GPa, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Nanoparticle films sputtered on substrates are key building blocks for photovoltaics, chemical/biological sensors, portable/wearable devices, magnetic devices, and catalysis. For these applications, high size and shape uniformities are highly demanded for improving their functional performance. However, flat substrate surface generally leads to unsatisfied size and shape uniformities. Here, a universal and sputtering rate‐tolerant strategy for improving the uniformities by introducing densely spaced nanoprotrusions (NPTs) at substrate surface is proposed. Unlike the conventional flat surface where the thermodynamic processes are substantially random, the NPTs can predefine the nucleation sites and confine the diffusion of sputtered atoms on the top, and eventually enable uniform nucleation and growth of nanoparticles. The morphological and surface plasmon spectroscopic analyses disclose that the size and particle shape uniformities of the sputtered nanoparticles are significantly improved by this strategy. Finally, an unprecedented universality and high tolerance to sputtering rate of the approach are confirmed by extending the approach to other material systems. Because of the simplicity of the working mechanism, the proposed strategy is expected to be readily extended to more material systems for applications. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA), characterized by polyarthritis, is a chronic, systemic and inflammatory autoimmune disease. In this study, we developed a dual‐modality multiparametric photoacoustic and ultrasound imaging technique, and successfully derived multiple parameters such as relative concentration of total hemoglobin (CHbT), ratio of angiogenesis, joint size and area of synovia to assess the development and treatment of RA. We established a model of adjuvant arthritis using a total number of 15 rats and randomly divided them into three groups: (a) targeted group in which the rats received targeted antirheumatic drugs; (b) nontargeted group in which the rats were treated with nontargeted antirheumatic drugs; (c) control group. We longitudinally monitored the joints of the rats in all three groups for up to 20 days and carried out quantitative analysis to evaluate the development and treatment of RA based on the derived parameters. The results suggest that the proposed dual‐modality imaging technique is able to assess the effectiveness of the RA treatment using quantitative hemodynamic and morphological parameters. To show the clinical feasibility of this technique, we performed in vivo joint studies of health volunteers to visualize both structures and inside hemodynamics of the distal interphalangeal joint. [ABSTRACT FROM AUTHOR]

Hemorrhagic shock, as an important clinical issue, is regarding as a critical disease with a high mortality rate. Unfortunately, existing clinical technologies are inaccessible to assess the hemorrhagic shock via hemodynamics in microcirculation. Here, we propose an ultracompact photoacoustic microscope to assess hemorrhagic shock using a rat model and demonstrate its clinical feasibility by visualizing buccal microcirculation of healthy volunteers. Both functional and morphological features of the microvascular network including concentration of total hemoglobin (CHbT), number of blood vessels (VN), small vascular density (SVD) and vascular diameter (VD) were derived to assess the microvascular hemodynamics of different organs. Animal studies show the feasibility of the proposed tool to assess and stage the hemorrhagic shock via microcirculation. in vivo oral imaging of healthy volunteers indicates the translational possibility of this technique for clinical evaluation of hemorrhagic shock. Hemorrhagic shock is a critical disease with a high mortality rate. We developed an ultracompact photoacoustic microscope to investigate the hemodynamics during the entire course of hemorrhagic shock. We evaluate the microvasculature in brain and three internal organs during hypotension and blood perfusion stages of hemorrhagic shock. The figure shows the design of imaging probe and the photoacoustic imaging of brain, intestine, ovary and bladder, respectively. [ABSTRACT FROM AUTHOR]