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To simultaneously improve the compatibility, flame retardancy and mechanical properties of ammonium polyphosphate (APP) based polyurethane, an efficient and facile strategy was developed, in which hydroxyl-functionalized APP (HAPP) was synthesized through ion-exchange reaction between APP and 3-aminopropanol, and then utilized as a multiple-function excipient for solvent-free two-component polyurethane (2K-PU) by chemical cross-linking. The curing behavior, mechanical and flame-retardant performances of HAPP cured 2K-PU, designating as 2K-PU/HAPP, were elaborately evaluated. Cone calorimeter results indicated that the conjugation of 15 wt% HAPP into 2K-PU significantly reduced the peak heat release rate (PHRR), total heat release (THR) and total smoke production (TSP) by 68.7%, 42.8% and 9.3%, respectively. Intriguingly, mechanical tests illustrated that the chemical incorporation of HAPP definitely improved the tensile strength of 2K-PU/HAPP while well-maintained the elongation at break, highlighting its attractive potential for industrial application. In addition, a flame-retardant mechanism for 2K-PU/HAPP was proposed. All aforementioned results distinctly demonstrate a feasible yet promising paradigm for fabricating APP-containing polyurethane. [ABSTRACT FROM AUTHOR]

Abstract: A novel hydrophilic cationic chain extender, 1,4‐butanediol di(3‐diethylamino‐2‐ hydroxylpropyl alcohol) ether (BDE), was successfully prepared, and then a series of lateral‐chain‐type cationic waterborne polyurethanes (CWPUs) with high solid content was synthesized. Compared with the traditional cationic chain extender, N‐methyl diethanol amine (MDEA), BDE with lateral amino groups shows more efficient hydrophilicity and ionization properties. CWPUs prepared from BDE possess lower viscosity, smaller particle size, and larger zeta‐potential. As predicted, stable CWPU latexes with higher solids content (≥50%) and lower hydrophilic group content were achieved. Further study indicated that other properties, including the molecular weight, glass transition temperature, thermal stability, and mechanical properties, of lateral‐chain‐type CWPUs were similar or superior to those of main‐chain‐type ones; no negative effect could be observed. [ABSTRACT FROM AUTHOR]

A photochromic long persistent luminescent polyurethane (PLPLPU) is prepared via incorporating amino-functionalized phosphors (NH2-SrAl2O4:Eu2+,Dy3+) and the red fluorescer 1-[(2-hydrocyethly)amino]anthraquinone (HAA) based on a colour conversion process. X-ray Diffraction (XRD), UV-vis absorption spectroscopy (UV), thermogravimetric analysis (TG), a fluorescence spectrophotometer and an afterglow brightness tester as well as the percentage of the migration test were utilized to characterize the structure and properties of the resultant samples. The photoluminescence emission spectrum of phosphors is overlapped with the excitation spectrum of HAA, which demonstrates that HAA can be selected as a colour conversion agent and can be excited by phosphors in the dark. PLPLPU shows red emission in daylight and yellow in the dark, exhibiting a pleasant photochromic long persistent luminescence effect. Furthermore, HAA in PLPLPU was confirmed to have a better thermal migration stability than the blend samples due to the chemical combination. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the interaction effects of hardness (75A, 80A, 90A), structures of tread groove (spacing, width, depth and orientation) and contaminants (dry, wet and vegetable oil) on coefficient of friction (COF) of TPU outsole of high-heeled shoe, by application the SATRA whole shoe tester with normalized ceramic tile. Results of univariate analysis show that (1) in the dry condition, orientation of tread groove was the main factor impacting the COF of TPU outsole; (2) ‘Orientation * contaminant', ‘Hardness * contaminant' and ‘Orientation * hardness * contaminant' had significant interaction impact on COF; (3) COF at the hardness of 80A was lower than that of 70A and 90A in the dry condition; while, those in the wet and oil conditions were controversial. Overall, variables of hardness, contaminant and orientation of tread groove were main influence factors in terms of slip resistance. [ABSTRACT FROM AUTHOR]

Photoresponsive polymers hold vast potential in the realm of drug delivery. Currently, most photoresponsive polymers use ultraviolet (UV) light as the excitation source. However, the limited penetration ability of UV light within biological tissues serves as a significant hindrance to their practical applications. Given the strong penetration ability of red light in biological tissues, the design and preparation of a novel red-light-responsive polymer with high water stability, incorporating the reversible photoswitching compound and donor-acceptor Stenhouse adducts (DASA) for controlled drug release is demonstrated. In aqueous solutions, this polymer exhibits self-assembly into micellar nanovectors (~33 nm hydrodynamic diameter), facilitating the encapsulation of the hydrophobic model drug Nile red (NR) within the micellar core. Upon irradiation by a 660 nm LED light source, photons are absorbed by DASA, leading to the disruption of the hydrophilic–hydrophobic balance of the nanovector and thereby resulting in the release of NR. This newly designed nanovector incorporates red light as a responsive switch, successfully avoiding the problems of photodamage and limited penetration of UV light within biological tissues, thereby further promoting the practical applications of photoresponsive polymer nanomedicines. [ABSTRACT FROM AUTHOR]

Idiopathic pulmonary fibrosis (IPF) affects an increasing number of people globally, yet treatment options remain limited. At present, conventional treatments depending on drug therapy do not show an ideal effect in reversing the lung damage or extending the lives of IPF patients. In recent years, more and more attention has focused on extracellular vesicles (EVs) which show extraordinary therapeutic effects in inflammation, fibrosis disease, and tissue damage repair in many kinds of disease therapy. More importantly, EVs can be modified or used as a drug or cytokine delivery tool, targeting injury sites to enhance treatment efficiency. In light of this, the treatment strategy of mesenchymal stem cell-extracellular vesicles (MSC-EVs) targeting the pulmonary microenvironment for IPF provides a new idea for the treatment of IPF. In this review, we summarized the inflammation, immune dysregulation, and extracellular matrix microenvironment (ECM) disorders in the IPF microenvironment in order to reveal the treatment strategy of MSC-EVs targeting the pulmonary microenvironment for IPF. [ABSTRACT FROM AUTHOR]

• A novel Fe/Mn@CF composite electrode is fabricated for the activation of sulfite. • Fe/Mn@CF-sulfite system exhibits satisfied degradation activity and stability. • Both free radical and non-free radical pathways boost pollutant degradation. • The presence of redox cycles of Fe and Mn promotes the activation of sulfite. • The synergistic interactions of electric field and metals lead to efficient sulfite activation. Sulfite has been proven to promote advanced oxidation processes (AOPs) to achieve low-cost and efficient degradation of contaminants, serving as an alternative to persulfate. In this study, a novel composite Fe/Mn@carbon felt (CF) electrode was successfully constructed to remove carbamazepine (CBZ). The capacity of the Fe/Mn@CF anode to activate sulfite was evaluated under various electrode preparation conditions and operating parameters. Results clearly indicated that the complete removal of CBZ was achieved in Fe/Mn@CF anode activated sulfite system under the specific conditions including Na 2 SO 4 electrolyte concentration of 50 mM, sulfite dosage of 1 mM, initial pH of 7, and current density of 1 mA/cm2. The capacity of Fe/Mn@CF anode for sulfite activation was further presented by its excellent reusability and stability in terms of CBZ removal and metal ion release. Both radical and non-radical pathways were significantly contributed to the CBZ removal, including OH, SO 4 · - , O 2 · - , 1O 2 , and other reasons. Density functional theory (DFT) calculations demonstrated that Fe-Mn bimetals effectively promoted sulfite activation, with the electric field further boosting the process of Fe-Mn valence cycle and oxidation. Overall, the novel Fe/Mn@CF activated sulfite system exhibited outstanding performance and had great potential for sustainable use in removing organics. [ABSTRACT FROM AUTHOR]

Background: Investigations on the potential effects of ambient fine particulate matter (PM2.5) on large for gestational age (LGA) are limited. Furthermore, no study has explored weekly-specific susceptible exposure windows for small for gestational age (SGA) and LGA. This study evaluated the associations of exposure to ambient PM2.5 over the preconception and entire-pregnancy periods with risks of SGA and LGA, as well as explored critical weekly-specific exposure windows.Methods: 10 916 singleton pregnant women with 24-42 completed gestational weeks from the Project Environmental and LifEstyle FActors iN metabolic health throughout life-course Trajectories between 2014 and 2016 were included in this study. Distributed lag models (DLMs) incorporated in Cox proportional-hazards models were applied to explore the associations of maternal exposure to weekly ambient PM2.5 throughout 12 weeks before pregnancy and pregnancy periods with risks of SGA and LGA after controlling for potential confounders.Results: For a 10-μg/m3 increase in maternal exposure to PM2.5, positive associations with SGA were observed during the 1st to 9th preconceptional weeks and the 1st to 2nd gestational weeks (P<0.05), with the strongest association in the 5th preconceptional week [hazard ratio (HR), 1.06; 95% confidential interval (CI), 1.03-1.09]. For LGA, positive associations were observed during the 1st to 12th preconceptional weeks and the 1st to 5th gestational weeks (P<0.05), with the strongest association in the 7th preconceptional week (HR, 1.10; 95% CI, 1.08-1.12).Conclusions: Exposure to high-level ambient PM2.5 is associated with increased risks of both SGA and LGA, and the most susceptible exposure windows are the preconception and early-pregnancy periods. [ABSTRACT FROM AUTHOR]

In recent years, polyurethane has drawn great attention because of its many advantages in physical and chemical performance. In this work, firstly, polyurethane was impregnated in a non-woven fabric (NWF). Then, polyurethane-impregnated NWF was coagulated utilizing a wet phase inversion. Finally, after alkali treatment, microfiber non-woven fabrics with a porous polyurethane matrix (PNWF) were fabricated and used as substrates. SnIn4S8 (SIS) prepared by a microwave-assisted method was used as a photocatalyst and a novel SIS/PNWF substrate with multiple uses and highly efficient catalytic degradation ability under visible light was successfully fabricated. The surface morphology, chemical and crystal structures, optical performance, and wettability of SIS/PNWF substrates were observed. Subsequently, the photocatalytic performance of SIS/PNWF substrates was investigated by the decomposition of rhodamine B (RhB) under visible light irradiation. Compared with SIS/PNWF-2% (2%, the weight ratio of SIS and PNWF, same below), SIS/PNWF-5% as well as SIS/PNWF-15%, SIS/PNWF-10% substrates exhibited superior photocatalytic efficiency of 97% in 2 h. This may be due to the superior photocatalytic performance of SIS and the inherent hierarchical porous structure of PNWF substrates. Additionally, the hydrophobicity of SIS/PNWF substrates can enable them to float on the solution and further be applied on an open-water surface. Furthermore, tensile strength and recycle experiments demonstrated that SIS/PNWF substrates possessed superior mechanical strength and excellent recycle stability. This work provides a facile and efficient pathway to prepare SIS/PNWF substrates for the degradation of organic pollutants with enhanced catalytic efficiency. [ABSTRACT FROM AUTHOR]

Background: Venovenous extracorporeal membrane oxygenation (VV ECMO) has been widely used for severe acute respiratory distress syndrome (ARDS) in recent years. However, the role of hemoadsorption in ARDS patients requiring VV ECMO is unclear. Methods: Therefore, we conducted a systematic review to describe the effect of hemoadsorption on outcomes of ARDS patients requiring VV ECMO and elucidate the risk factors for adverse outcomes. We conducted and reported a systematic literature review based on the principles derived from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The systematic review searched Embase, CINHAL, and Pubmed databases for studies on ARDS patients receiving hemoadsorption and VV ECMO. The demographic data, clinical data and biological data of the patients were collected. Results: We ultimately included a total of 8 articles including 189 patients. We characterized the population both clinically and biologically. Our review showed most studies described reductions in inflammatory markers and fluid resuscitation drug dosage in ARDS patients with Coronavirus disease 2019 (COVID-19) or sepsis after hemoadsorption. Conclusion: Because most of the studies have the characteristics of high heterogeneity, we could only draw very cautious conclusions that hemoadsorption therapy may enhance hemodynamic stability in ARDS patients with COVID-19 or sepsis receiving VV ECMO support. However, our results do not allow us to draw conclusions that hemoadsorption could reduce inflammation and mortality. Prospective randomized controlled studies with a larger sample size are needed in the future to verify the role of hemoadsorption in ARDS patients requiring VV ECMO. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel fluorinated diisocyanate monomer was synthesized. • Wetting ability on low surface energy substrate and water/organic solvent resistance of WPU were improved. • This study provides a new way to synthesized high-performance waterborne polyurethane. Abstract A series of fluorine-containing water-based polyurethane (FWPU) were synthesized by using fluoro alcohol-terminated isocyanate trimer (F-HDIT) prepared from 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-1-octanol (TFO) and hexamethylene diisocyanate trimer (HDIT). The structure of F-HDIT and the wetting and spreading ability, hydrophobic and solvent-resistance properties of FWPU were investigated in detail. The results indicated that with the increase of F-HDIT, the latex particle size, the water/solvent resistance and elongation at break of FWPU increased. More interestingly, the wetting and spreading ability on non-polar substrates was enhanced with the introduction of F-HDIT and the surface tension of FWPU film/latex was decreased by 69.5%/17.3%. Meanwhile, the water/methylene iodide contact angles were increased from 54.0°/34.1° to 121.8°/90.7° respectively, showing good hydrophobic and solvent-repellence characteristics. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • GO was covalently functionalized with phosphorus-nitrogen flame retardant. • Nanostructured WPU/graphene composite with molecular-level uniformity was prepared. • Flame retardancy, thermal and mechanical properties of WPU were synchronously enhanced. • Flame-retardant mechanism was comprehensively investigated with detailed evidences. Abstract Despite considerable advances, it remains imperative but challenging to develop high-performance waterborne polyurethane (WPU) which combines with robust mechanical, thermal and flame retardant properties. Considering its unique structure and properties, graphene has been reported as a potential alternative to ameliorate the integrate performance of polyurethane. However, one of the intractable handicaps is how to effectively disperse graphene and enhance its interfacial interaction towards polymer matrix. We herein demonstrate the fabrication of WPU composite by covalently conjugating with hydroxyl-functionalized graphene oxide (fGO), which was wrapped with P-N flame retardants, using an in situ polymerization strategy. Results indicated that a nanostructured WPU/graphene composite (WPU/fGO) with molecular-level uniformity was prepared. Compared with pure WPU, the peak heat release rate and total heat release were significantly reduced by 39.2% and 18.6%. The well dispersion, lamellae blocking effect of graphene nanosheets and the catalytic charring performance of P-N flame retardant were conductive to the improved fire safety. Moreover, WPU/fGO composite exhibited a 139% enhancement in tensile strength, while maintaining the superior elongation at break (high as 857.5%). Overall, this effective yet promising paradigm may provide an achievable solution toward developing graphene-based polymer nanocomposites simultaneously with high fire safety and well-balanced comprehensive performances. [ABSTRACT FROM AUTHOR]

The modular synthesis of biomass-based diols (BDOs) in a facile and general way remains a grand challenge. To surmount this hurdle, here we present a new synthetic route, namely employing a Passerini reaction followed by a thiol–ene click reaction, to prepare BDOs. By selecting readily available starting biobased materials, including acids, aldehydes, isonitriles, and hydroxythiol as the building blocks, this method offers a convenient and efficient way for accessing structurally diverse BDOs without the need for catalysts and under mild reaction conditions. Specifically, the ability of our method to precisely regulate BDOs' aliphatic pendant chain length is demonstrated, which facilitates the development of waterborne polyurethane films with exceptional waterproof performance. By simplifying the BDO synthesis process, this method is poised to lead to a prosperous development for BDOs. [ABSTRACT FROM AUTHOR]

The gut is the body's largest immune organ, and the intestinal barrier prevents harmful substances such as bacteria and toxins from passing through the gastrointestinal mucosa. Intestinal barrier dysfunction is closely associated with various diseases. However, there are currently no FDA-approved therapies targeting the intestinal epithelial barriers. Long noncoding RNAs (lncRNAs), a class of RNA transcripts with a length of more than 200 nucleotides and no coding capacity, are essential for the development and regulation of a variety of biological processes and diseases. lncRNAs are involved in the intestinal barrier function and homeostasis maintenance. This article reviews the emerging role of lncRNAs in the intestinal barrier and highlights the potential applications of lncRNAs in the treatment of various intestinal diseases by reviewing the literature on cells, animal models, and clinical patients. The aim is to explore potential lncRNAs involved in the intestinal barrier and provide new ideas for the diagnosis and treatment of intestinal barrier damage-associated diseases in the clinical setting. [ABSTRACT FROM AUTHOR]

Crush syndrome (CS), also known as traumatic rhabdomyolysis, is a syndrome with a wide clinical spectrum; it is caused by external compression, which often occurs in earthquakes, wars, and traffic accidents, especially in large-scale disasters. Crush syndrome is the second leading cause of death after direct trauma in earthquakes. A series of clinical complications caused by crush syndrome, including hyperkalemia, myoglobinuria, and, in particular, acute kidney injury (AKI), is the main cause of death in crush syndrome. The early diagnosis of crush syndrome, the correct evaluation of its severity, and accurate predictions of a poor prognosis can provide personalized suggestions for rescuers to carry out early treatments and reduce mortality. This review summarizes various methods for the diagnostic and predictive evaluation of crush syndrome, including urine dipstick tests for a large number of victims, traditional and emerging biomarkers, imaging-assisted diagnostic methods, and developed evaluation models, with the aim of providing materials for scholars in this research field. [ABSTRACT FROM AUTHOR]

A thermochromic luminous polyurethane (TLPU), which can reversibly change its color and can exhibit fluorescence emission with the change in temperature, was prepared through incorporating long persistent luminescent phosphors (SrAl2O4:Eu2+,Dy3+) and thermochromic pigment (TP). X-Ray Diffraction (XRD) patterns, differential scanning calorimetry (DSC) curves, thermogravimetic analysis results (TG), UV-vis absorption spectra (UV), reflectance spectra and fluorescence spectra were obtained to characterize the properties of the resultant samples. The phosphorescence colors were directly related to the temperature because of the inner phase transition of the thermochromic pigment on heating. TLPU was red in daylight under low temperature conditions and turned white as the temperature rose. After the stoppage of excitation and in the dark, it emitted yellow light while cooling and turned green as the temperature increased. [ABSTRACT FROM AUTHOR]

Amino-functionalized glass microspheres (NH 2 -GM) grafted with 3-aminopropyltriethoxysilane (APTS) were synthesized and well characterized by X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and scanning electron microscope (SEM). Then the NH 2 -GM was covalently incorporated into polyurethane (PU) matrix through urea linkages to fabricate a composite with retro-reflective effect, and the influence of NH 2 -GM content on the retro-reflective performance, glass transition temperature, morphology structure and mechanical properties of the resultant glass microspheres based retro-reflective polyurethane (GMPU) were investigated. Results demonstrate that GMPU maintains initial retro-reflective properties and reflects bright light under vertical angle incidence in darkness. Moreover, compared with PU directly blending with GMs (GM/PU), GMPU shows clear improved compatibility and interfacial interactions between PU and NH 2 -GMs, as evidenced by the higher glass transition temperature and enhanced mechanical properties of GMPU hybrids. [ABSTRACT FROM AUTHOR]

Light-degradable hydrogels have a wide range of application prospects in the field of biomedicine. However, the provision of a facile synthetic approach to light-degradable hydrogels under mild conditions remains a challenge for researchers. To surmount this challenge, a facile synthetic approach to UV-degradable hydrogels is demonstrated in this manuscript. Initially, an UV-degradable crosslinker (UVDC) having o-nitrobenzyl ester groups was synthesized in a single step through the employment of the Passerini three-component reaction (P-3CR). Both 1H NMR and MS spectra indicated the successful synthesis of high-purity UVDC, and it was experimentally demonstrated that the synthesized UVDC was capable of degradation under 368 nm light. Furthermore, this UVDC was mixed with 8-arm PEG-thiol (sPEG20k-(SH)8) to promptly yield an UV-degradable hydrogel through a click reaction. The SEM image of the fabricated hydrogel exhibits the favorable crosslinking network of the hydrogel, proving the successful synthesis of the hydrogel. After continuous 368 nm irradiation, the hydrogel showed an obvious gel-sol transition, which demonstrates that the hydrogel possesses a desirable UV-degradable property. In summary, by utilizing solely a two-step reaction devoid of catalysts and hazardous raw materials, UV-degradable hydrogels can be obtained under ambient conditions, which greatly reduces the difficulty of synthesizing light-degradable hydrogels. This work extends the synthetic toolbox for light-degradable hydrogels, enabling their accelerated development. [ABSTRACT FROM AUTHOR]

Eethylenediamine (EDA), isophorone diamine (IPDA), diethylenetriamine (DETA), N- β- (aminoethyl)- γ- aminopropylmethyl dimethoxysilane (KH602) and polyether amine (D-230) were used as post chain extenders, a series of solvent-free high-solid content water-based polyurethanes (WPU) were prepared. The reactivity of different post chain extenders and the effects of different R values (mole ratio of –NCO/-OH) on solid content as well as the effects of chain extension degree on properties of WPU were investigated in detail. Among of water, small molecule diamine and diol, diamine with higher activity is preferred to water to complete the post chain extension reaction and improves the mechanical properties of WPU. When the R value is higher than 1.7 and the post chain extension degree is controlled at 70%, the viscosity of the solvent-free prepolymer is small enough to be emulsified, and the as-prepared WPUs show more excellent thermodynamic properties. In comparison, the cyclic chain extender such as IPDA can improve the mechanical properties and heat resistance of WPU, crosslinking type chain extenders involving DETA and KH602 can improve the heat resistance and anti-sticking of WPU coating. Whilst the WPU prepared by the chain extender containing flexible space, such as D-230, has a very low modulus and is suitable for preparing soft–type WPU. [ABSTRACT FROM AUTHOR]

Repetitive low-level blast (rLLB) exposure is a potential risk factor for the health of soldiers or workers who are exposed to it as an occupational characteristic. Alveolar macrophages (AMs) are susceptible to external blast waves and produce pro-inflammatory or anti-inflammatory effects. However, the effect of rLLB exposure on AMs is still unclear. Here, we generated rLLB waves through a miniature manual Reddy-tube and explored their effects on MH-S cell morphology, phenotype transformation, oxidative stress status, and apoptosis by immunofluorescence, real-time quantitative PCR (qPCR), western blotting (WB) and flow cytometry. Ipatasertib (GDC-0068) or PDTC was used to verify the role of the Akt/NF-κB signaling pathway in these processes. Results showed that rLLB treatment could cause morphological irregularities and cytoskeletal disorders in MH-S cells and promote their polarization to the M1 phenotype by increasing iNOS, CD86 and IL-6 expression. The molecular mechanism is through the Akt/NF-κB signaling pathway. Moreover, we found reactive oxygen species (ROS) burst, Ca2+ accumulation, mitochondrial membrane potential reduction, and early apoptosis of MH-S cells. Taken together, our findings suggest rLLB exposure may cause M1 polarization and early apoptosis of AMs. Fortunately, it is blocked by specific inhibitors GDC-0068 or PDTC. This study provides a new treatment strategy for preventing and alleviating health damage in the occupational population caused by rLLB exposure. [ABSTRACT FROM AUTHOR]

ABSTRACT A fluorescent fluorescent waterborne polyurethane (FWPU) was synthesized by conjugating fluorescer, isodium 4,4 ′-bis[4-anilino-6-hydroxyethylamino-6-(2-choloronilino-1,3,5-triazin-2-yl)amino]stilbene-2,2 ′-disulphonate (RSW), into polyurethane backbone as a chain extender. The expected structure of FWPU was confirmed by Fourier transform infrared, 1H nuclear magnetic resonance, and UV−vis spectrophotometer, and the effect of fluorescer content, temperature, as well as quencher on the fluorescence performances of FWPU was investigated in detail. Results reveal that covalently conjugation has unconspicuous effect on optical performance, and FWPU shows similar fluorescence intensity to fluorescer RSW except for a red shift of about 10 nm in maximum absorption wavelengths. Further study finds that there is a positive correlation between the concentration of fluorescer and the fluorescence intensity of FWPU; however, the opposite effect is obtained when the concentration exceeds 1 × 10−5 mol/L, which is attributed to the concentration self-quenching. Although high temperature will decrease the intensity of fluorescence, the fluorescence components in FWPU shows high resistance to fluorescence quencher and thermal decomposition as a consequence of chemical combination with the polymer chain. [ABSTRACT FROM AUTHOR]

Previous studies have found several biomarkers for acute respiratory distress syndrome (ARDS), but the accuracy of most biomarkers is still in doubt due to the occurrence of other comorbidities. In this systematic review and meta-analysis, we aimed to explore ideal ARDS biomarkers which can reflect pathophysiology features precisely and better identify at-risk patients and predict mortality. Web of Science, PubMed, Embase, OVID, and the Cochrane Library were systematically searched for studies assessing the reliability of pulmonary-originated epithelial proteins in ARDS. A total of 32 studies appeared eligible for meta-analysis, including 2654 ARDS/ALI patients in this study. In the at-risk patients' identification group, the highest pooled effect size was observed in Krebs von den Lungren-6 (KL-6) (SMD: 1.17 [95% CI: 0.55, 1.79]), followed by club cell proteins 16 (CC16) (SMD: 0.74 [95% CI: 0.01, 1.46]), and surfactant proteins-D (SP-D) (SMD: 0.71 [95% CI: 0.57, 0.84]). For the mortality prediction group, CC16 exhibited the largest effect size with SMD of 0.92 (95% CI: 0.42, 1.43). Meanwhile, the summary receiver operating characteristic (SROC) of CC16 for ARDS diagnosis reached an AUC of 0.80 (95% CI: 0.76, 0.83). In conclusion, this study provides a ranking system for pulmonary-originated epithelial biomarkers according to their association with distinguishing at-risk patients and predicting mortality. In addition, the study provides evidence for the advantage of biomarkers over traditional diagnostic criteria. The performance of biomarkers may help to clinically improve the ARDS diagnosis and mortality prediction. [ABSTRACT FROM AUTHOR]

A type of polyester-based self-matting waterborne polyurethane (ESMWPU) with an excellent matte effect of 0.8° and transmittance of 78.5% for PVC artificial leather was synthesized. The influence of synthesis parameters, including R value, crosslinking and hydrophilic group content, on coating gloss and transmittance was investigated. Meanwhile, the properties necessary for applying water-based resins to plasticized PVC were detailed. The results demonstrated that R value, crosslinking degree and hydrophilic group content synergistically decided the morphological changes of latex particles during their film-forming process in three aspects: particle stiffness, three-dimensional structure and particle size, respectively. With optimized parameters of R = 1.9, TMP = 2 wt% and DMPA = 1.75 wt%, ESMWPU latex particles stabilized their spherical shapes without collapsing in the film-forming process and created a rough surface, resulting in a matte effect. In terms of application performance, good wetting and adhesion for ESMWPU to a plasticized PVC surface was achieved with a 2 wt% leveling agent load. Moreover, due to the high cohesion energy of ester bonds and intermolecular hydrogen bonds, this type of polyester-based ESMWPU also depicted admirable thermal adhesion resistance. All aforementioned results distinctly demonstrate a feasible yet promising paradigm for applying ESMWPU on PVC artificial leather. [ABSTRACT FROM AUTHOR]

Systemic inflammatory factors are inconsistently associated with the pathogenesis of chronic obstructive pulmonary disease (COPD). We conducted a systematic review and meta-analysis to summarize the evidence supporting the association between systemic inflammation and the risk of COPD. Pertinent studies were retrieved from PubMed, EmBase, and the Cochrane Library until April 2015. A random-effects model was used to process the data, and the analysis was further stratified by factors affecting these associations. Sensitivity analyses for publication bias were performed. We included 24 observational studies reporting data on 10,677 COPD patients and 28,660 controls. Overall, we noted that COPD was associated with elevated serum CRP (SMD: 1.21; 95%CI: 0.92–1.50; P < 0.001), leukocytes (SMD: 1.07; 95%: 0.25–1.88; P = 0.010), IL-6 (SMD: 0.90; 95%CI: 0.48–1.31; P < 0.001), IL-8 (SMD: 2.34; 95%CI: 0.69–4.00; P = 0.006), and fibrinogen levels (SMD: 0.87; 95%CI: 0.44–1.31; P < 0.001) when compared with control. However, COPD was not significantly associated with TNF-α levels when compared with control (SMD: 0.60; 95%CI: -0.46 to 1.67; P = 0.266). Our findings suggested that COPD was associated with elevated serum CRP, leukocytes, IL-6, IL-8, and fibrinogen, without any significant relationship with TNF-α. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of interface angles on the coupling efficiency of a fiber Fabry-Perot interferometer (FFPI) sensor using both simulation and experimental methods. The FFPI sensor, which consists of a single-mode fiber (SMF), hollow-core fiber (HCF), and diaphragm, has its coupling efficiency determined by the generalized scattering matrix of the cascaded fiber system. To obtain the interface angles of the FFPI sensor, a new on-line monitoring system is developed based on microscopic images of the FFPI cavity and an image processing algorithm using OpenCV. By combining the eigenmode expansion method (EME) model and the online interface angle measurement technique, the coupling efficiency and spectral contrast of the FFPI cavity are evaluated and improved. Additionally, the corresponding working point in the intensity demodulation based FFPI sensor can be quickly identified. Using this method, an FFPI sensor with a spectral contrast of over 35 dB is achieved, which is significantly higher than existing similar sensors, and its sensitivity also reaches 50.80 mV/MPa. This work also holds significance for controlling and enhancing the spectral characteristics of other cascaded fiber optic sensors. • Advances FFPI fiber optic sensing to >35 dB spectral contrast & 50.80 mV/MPa pressure sensitivity. [ABSTRACT FROM AUTHOR]

• Proinflammatory macrophages and Th17 cells mediate acute lung injury in smoke inhalation injury (SII). • MSCs ameliorate lung inflammatory injury by affecting M1/M2 and Th17/Treg immune homeostasis in SII. • MSCs regulate the M1/M2-Th17/Treg immune homeostasis axis via alveolar macrophage-derived IL-23. Smoke inhalation injury (SII) is the leading cause of death in fire burn patients. The inflammatory response induced by smoke inhalation is a significant factor in the development of acute lung injury or acute respiratory distress syndrome (ALI/ARDS). Mesenchymal stem cells (MSCs) can alleviate various inflammatory diseases by regulating the polarization of macrophages from the M1 to the M2 phenotype. Moreover, MSCs can facilitate the inflammatory response by regulating Th17/Treg homeostasis. However, little is known about the associations among MSCs, M1/M2 macrophages and Th17/Treg homeostasis. Therefore, the purpose of this study was to evaluate whether MSCs affect subsequent Th17/Treg differentiation and immune homeostasis by regulating M1/M2 polarization in SII. Our results showed that bone marrow mesenchymal stem cells (BMSCs) ameliorated lung inflammatory injury and fibrosis after SII by affecting the polarization of alveolar macrophages (AMs) from the M1 to the M2 phenotype. Moreover, BMSCs maintain Th17/Treg immune homeostasis by increasing the proportion of Treg cells and decreasing the proportion of Th17 cells. In vitro, we further demonstrated that BMSCs promoted the polarization of AMs from the M1 to the M2 phenotype and decreased IL-23 levels. Reduced IL-23 decreased Th17 differentiation and promoted Th17/Treg balance. Therefore, BMSCs ameliorate the inflammatory response and lung damage after SII through regulating M1/M2 polarization and subsequent Th17/Treg immune homeostasis, which are linked to alveolar macrophage-derived IL-23. These findings provide novel insight into how BMSCs regulate the M1/M2-Th17/Treg immune homeostasis axis and provide new therapeutic targets for more effective control of the inflammatory response after SII. [ABSTRACT FROM AUTHOR]

The ultrahigh concentration of bilirubin (BR) is recognized as a key factor leading to biliary cirrhosis and irreversible brain damage, with the efficient removal of BR from blood being an effective therapy against these conditions. However, the practical application of adsorbents for blood purification is often compromised by their poor regenerative performance. Therefore, by leveraging the excellent structure-function properties of stimuli-responsive materials, we developed photoregenerable nanoadsorbents (SiO 2 @MAzoPy– x) with excellent cyclic removal performance. We employed azobenzene macromolecule brushes as the functional ligand to enhance the adsorption performance of the nanoadsorbents and enable efficient regeneration. The best-performing nanoadsorbent exhibited BR adsorption rates of 69.71 % and 65.20 % in phosphate-buffered saline (PBS) and simulated plasma, respectively, and showed superior adsorption efficiency in patients' serum compared to the unmodified SiO 2 (≤ 5.4 %). The binding mechanism suggested that BR and the nanoadsorbent interacted through hydrophobic and electrostatic forces. Importantly, the nanoadsorbents could be photoregenerated with a recovery rate of 99 % in PBS after five regeneration experiments using a green process. Owing to their superior photoregenerative properties, the proposed nanoadsorbents show promise for clinical application. [Display omitted] [ABSTRACT FROM AUTHOR]

The oxygenator with hollow fiber membranes (HFMs) is the key component of the extracorporeal membrane oxygenation which allows the blood to be oxygenated and the carbon dioxide to be removed. The poly(4-methyl-1-pentene) (PMP) is recognized as the optimal oxygenated membrane material with high gas permeability coefficient, and the oxygenated membrane fabricated from it has an asymmetric structure that can resist plasma leakage for a long period of time. However, the relatively low rigidity of PMP oxygenated membrane makes it difficult to be processed in subsequent weaving and applications, during which deformation and fracture of HFMs often happen. In this work, the polymer alloy oxygenated membranes are fabricated by blending polypropylene (PP) as a high rigidity reinforcement agent with PMP via thermally induced phase separation (TIPS). Firstly, the effect of the PP content on phase separation structure and crystallization of alloy flat sheet membrane are investigated. When the PP content is 15 wt%, the rigidity of the alloy membrane reinforces dramatically. The elastic modulus and tensile strength of the PMP-PP-15 alloy membrane is 288.5 ± 12.4 MPa and 8.3 ± 0.4 MPa, respectively, which is 275.7 % and 96.7 % higher than that of the PMP membrane. Furthermore, PMP-PP-15 alloy HFM are fabricated under the optimum polymer composition. The elastic modulus of the PMP-PP-15 alloy HFM is 312.6 ± 16.0 MPa, which is 679.6 % higher than that of the PMP HFM and 40.1 % higher than that of the commercial PMP HFM. Meanwhile, the tensile strength and fracture stress are 15.4 ± 0.7 MPa and 186 ± 12.2 cN, respectively, which are both higher than those of the PMP and commercial PMP HFM. In addition, the PMP-PP-15 alloy HFM shows high gas permeability and oxygenation performance. This study might provide a convenient method to achieve rigidity reinforcement of PMP-based oxygenated membranes with great potential for application. [Display omitted] • PP as a high rigidity reinforcement agent with PMP to construct polymer alloy. • PMP-PP-15 alloy membrane exhibits moderate phase separation leading to high rigidity. • PMP-PP-15 alloy HFM exhibits high rigidity than that of the commercial PMP HFM. • PMP-PP-15 alloy HFM shows high gas permeability and oxygenation performance. [ABSTRACT FROM AUTHOR]

[Display omitted] A novel anti-smudge coating, based on waterborne polyurethane (WPU), Polydimethylsiloxane (PDMS) and Hexamethoxymethylmelamine (HMMM) was constructed. Specifically, hydroxyl capped WPU emulsions grafted with PDMS (WPU-g-PDMS X) were prepared firstly, then the Hexamethoxymethylmelamine (HMMM) was used as the crosslinking agent to block the polar hydrophilic hydroxyl groups and the carboxyl groups in WPU-g-PDMS X and increase the cross-linking density of the coating. Oily markers, water, hexadecane, fingerprint liquid, and common liquids in life (milk, coffee, ink and cooking oil) were utilized to demonstrate the anti-graffiti and self-cleaning characteristics of coatings. Aside from having great transparency and exceptional resistance to liquid corrosion, the coating still retains its anti-smudge capabilities even when bent or impacted, and they also exhibit 5B adhesion and 5H pencil hardness. This work provides novel idea and strategy for the preparation of WPU anti-smudge coatings. [ABSTRACT FROM AUTHOR]

[Display omitted] A novel anti-smudge coating, based on waterborne polyurethane (WPU), Polydimethylsiloxane (PDMS) and Hexamethoxymethylmelamine (HMMM) was constructed. Specifically, hydroxyl capped WPU emulsions grafted with PDMS (WPU-g-PDMS X) were prepared firstly, then the Hexamethoxymethylmelamine (HMMM) was used as the crosslinking agent to block the polar hydrophilic hydroxyl groups and the carboxyl groups in WPU-g-PDMS X and increase the cross-linking density of the coating. Oily markers, water, hexadecane, fingerprint liquid, and common liquids in life (milk, coffee, ink and cooking oil) were utilized to demonstrate the anti-graffiti and self-cleaning characteristics of coatings. Aside from having great transparency and exceptional resistance to liquid corrosion, the coating still retains its anti-smudge capabilities even when bent or impacted, and they also exhibit 5B adhesion and 5H pencil hardness. This work provides novel idea and strategy for the preparation of WPU anti-smudge coatings. [ABSTRACT FROM AUTHOR]

A type of porous polyurea microspheres for matting coating were prepared by precipitation polymerization in H2O/Acetonitrile (AN) solution, using isophorone diisocyanate (IPDI) as polymerized monomer, 2, 4-diaminobenzenesulfonic acid sodium salt as hydrophilic monomer and polyvinylpyrrolidone (PVP) as porogen. The effect of the type of porogen, reaction temperature, dry methods, post-perforation method and polyvinylpyrrolidone loading on the surface porosity was investigated. Meanwhile, the effect of the surface porosity and roughness of microspheres on the matting properties of the coating was also investigated. The results indicated that PVP porogen has played an important role in regulating the surface porosity of microspheres and shows superior perforation. When 15 wt% PVP (based on isophorone diisocyanate loading) was used as porogen, the reaction was carried at 50 °C in a shorter time, and the crude product was dried in a state of water dispersion at 100 °C, the resultant microspheres with maximal porous surface can be achieved. Post-perforation can further increase the surface roughness and porosity of polyurea microspheres without changing its particle size. When 5 wt% porous polyurea microspheres were added to the water-based polyurethane (WPU) coating, the gloss of the coating decreased from 6.27° to 1.14° (60° incident angle). [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is an important complication of rhabdomyolysis (RM), but there is lack of effective treatments. Ulinastatin (UTI) is a broad-spectrum serine protease inhibitor isolated and purified from human urine with strong anti-inflammatory and cytoprotective actions. The aim of this research was to investigate the effect and potential mechanism of UTI on RM-induced AKI (RM-AKI). We established RM-induced AKI model and myoglobin (Mb)-stimulated NRK-52E cell model. In vivo, twenty-four rats were randomly divided into three groups (n = 8): control, RM-AKI, and RM-AKI + UTI. In vitro, the NRK-52E cells were divided into six groups according to the different treatment method. Mb-stimulated NRK-52E cells were treated with UTI or si-TLR4 transfection to characterize the mechanisms of UTI in RM-AKI. Indicators of the kidney injury, cell viability, cell cycle, oxidative stress, inflammation, apoptosis, and TLR4/NF-κB signaling pathway were assessed. In vivo and in vitro, UTI significantly decreased the expression of TLR4 and p65. In vivo, UTI significantly improved renal function and reduced inflammatory reaction and kidney injury. In vitro, UTI protected NRK-52E cells from Mb stimulation by suppressing cell cytotoxicity, cell cycle inhibition, overproduction of ROS, inflammation, and apoptosis. Additionally, UTI played a protective role by downregulating the TLR4 expression. The results indicate that UTI alleviates RM-AKI by suppressing the inflammatory response and apoptosis via inhibiting TLR4/NF-κB signaling pathway. Our study provides a new mechanism for the protective effect of UTI on RM-AKI. [ABSTRACT FROM AUTHOR]

A novel halogen-free flame retardant diol bearing pendant organophosphate group, 2-ethyl-2-(2-oxo-5,5-dimethyl-1,3,2-dioxaphosphorinanyl-2-methylene)-1,3-propanediol (EPPD), was designed and synthesized, and then covalently conjugated into polyurethane as chain extender to prepare a series of phosphorus-containing flame retardant waterborne polyurethanes (PWPU). The chemical structures of the resultant EPPD and PWPU were confirmed by FTIR, 1 H and 31 P NMR, respectively. Simultaneously, the flammability and thermal behavior of PWPU films were systematically investigated by limiting oxygen index (LOI) test, UL-94 vertical burning experiment and thermogravimetric (TG) as well as residual char analysis. An LOI value of 26.6% and a UL-94 V-0 rating can be achieved when the PWPU sample conjugated with 12 wt% EPPD, showing good inherent flame retardancy. TGA and residual char analysis indicate that the incorporation of EPPD induces a slight decrease of the thermal stability due to the relatively weaker bond energy of O P O, whereas the formed phosphoric and polyphosphoric acid during combustion can impart PWPU with nonflammability owing to the promoting of rugged carbonaceous char in the condensed phase which shields the underlying polyurethane from further attacking of heat flux. Meanwhile, hydrolytic stability study demonstrates that PWPU with organophosphate moieties linking in the side-chain exhibits better hydrolysis resistance than that with phosphoester bond conjugated in the backbone. [ABSTRACT FROM AUTHOR]

• Innovatively introducing a 50 nm wide narrow slit in photonic crystal waveguides to highly concentrate the electric field generated by EEG signals in the resonant cavity. • The experimental results show that this sensor has an ultra-high sensing sensitivity of up to 142.64 nm/V and is able to detect EEG signals of 10 μV size. • Due to the optically coupled nanoscale sensing structure, this sensor has a compact footprint as small as 4.29 mm2. • The proposed sensor can be easily integrated with other photonic devices at the chip level, providing a novel solution for the development of miniature physiological sensors. Noninvasive electroencephalogram signal detection with high sensitivity and a high signal-to-noise ratio has attracted much attention. To achieve high-sensitivity electroencephalogram (EEG) sensing, a photonic crystal side-coupled microcavity nanoscale sensor based on Fano resonance is proposed with nano electro-optic sensing technology as the core support. This configuration comprises a nanobeam resonant cavity, a waveguide, and an electrical slab. The substantial overlap between the optical and electric fields within the resonant cavity is analyzed, and the sensor's electric field sensing performance is assessed. Due to the optically coupled nanoscale sensing structure that is adopted in the sensor, the device has an ultrahigh voltage sensing sensitivity of up to 142.64 nm/V and a compact footprint as small as 4.29 mm2, enabling real-time sensing of EEG signals of 10 μV and below. These improvements overcome the technical challenges of low precision and large size as are associated with existing optical devices used for medical monitoring. [ABSTRACT FROM AUTHOR]

To mitigate harmful volatile organic compounds (VOCs) emissions and adhere to environmental policies such as the carbon peak strategy, the development of solvent-free polyurethane (SFPU) coating materials has emerged as a crucial endeavor. In this study, a type of SFPU system, involving blocked polyurethane prepolymers (PUPs), thermal expandable microspheres (TEMs) foaming agent and diamine curing agent, was developed to construct foamed synthetic leather coating. Notably, the blocking strategy endowed the system with desirable storage stability and pot-life. The deblocking temperature range of both dimethyl and methyl ethyl ketoxime blocked PUP were 70 °C–120 °C, which was lower than that of the foaming temperature range of the prepared TEMs (118 °C–122 °C). Due to the lower deblocking temperature and curing activation energy, the curing process of SFPU system was prior to foaming in application. Further study indicates that 2 wt% TEMs loading could effectively enhance the softness and resilience of coating and increase its water vapor permeability greatly, while higher amount of TEMs decreased resilience and peel strength of coatings. Based on the compatibility between curing and foaming process, an abbreviated "two-coating and three-baking" solvent-free polyurethane synthetic leather-making process was constructed by integrating the blocking strategy and TEM foaming technology. This work provides a guidance for the synthesis of SFPU with high storage stability and long pot-life, and the sustainable solutions for the synthetic leather manufacture in line with the carbon peak strategy. [Display omitted] • Solvent-free polyurethane prepolymers blocked with ketoxime were prepared. • The blocking strategy endowed system with desirable storage stability and pot-life. • Thermal expansion microspheres were prepared to develop foam coatings. • Construction of the "Two-coating and Three baking" synthetic leather-making process. [ABSTRACT FROM AUTHOR]

Sepsis is a common critical clinical disease with high mortality that can cause approximately 10 million deaths worldwide each year. Acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) is a common clinical complication of sepsis, which occurs primarily as diffuse alveolar injury, hypoxemia, and respiratory distress. The mortality rate of ALI/ARDS is as high as 30%-40%, which greatly endangers human health. Due to the unclear pathogenesis of ALI/ARDS, its treatment is still a worldwide problem. At present, clinical treatment mainly relies on lung-protective ventilation, prone position ventilation, and fluid management. However, there is a lack of effective and specific treatment measures. In recent years, domestic and foreign scholars have committed to basic research on ALI/ARDS, trying to further clarify its pathogenesis and find new targets and methods for the treatment of ALI/ARDS. In this review, we summarize the signaling pathways related to alveolar injury and repair in sepsis-induced ALI/ARDS and their latest research progress. They include the NF-κB, JAK2/STAT3, mitogen-activated protein kinase (MAPK), mTOR, and Notch signaling pathways. Understanding the molecular mechanisms of these signaling pathways in sepsis-induced ALI/ARDS may provide new targets and ideas for the clinical treatment of this disease. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanomechanics of anion − π interactions containing fluoroarene was quantified in aqueous solutions. • Anion − π interaction strength was affected by salt, contact time and fluoroarene systems. • Competing anion replacing the carboxylate radical can interact with pentafluorophenyl (C 6 F 5). • SMFS was applied to determine the anion − π interaction strength 27.45 kJ/mol at the single-molecule level. Despite the much progress in developing π-conjugated fluoroarene moieties based functional materials in which anion − π interactions are commonly involved, it remains challenging to quantitatively characterize the nanomechanical interaction mechanism of these anion − π systems, particularly in aqueous solutions. In this study, we reported the first experimental quantification of the nanomechanics of anion − π interactions between π-conjugated fluoroarene moieties and carboxylate anions in aqueous solutions through direct molecular force measurements, with a special focus on the impact of the anion species, concentration and of the substitution effect of aromatic side group. The results using surface forces apparatus (SFA) and single-molecule force spectroscopy (SMFS) provide complementary evidences to demonstrate that the robust and reversible adhesion measured between the fluoroarene π systems and carboxylate anions was mainly attributed to anion − π interaction. Moreover, their nanomechanical properties were also systematically scrutinized, with the interaction strength being found to be significantly determined by the contact time, the type of fluoroarene systems (PFST > DFST) and the type of anions and ion concentration (HPO 4 2- > CO 3 2– > I- > Cl- ≈ NO 3 – > F-). [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is an overactivated inflammatory response caused by direct or indirect injuries that destroy lung parenchymal cells and dramatically reduce lung function. Although some research progress has been made in recent years, the pathogenesis of ALI/ARDS remains unclear due to its heterogeneity and etiology. MicroRNAs (miRNAs), a type of small noncoding RNA, play a vital role in various diseases. In ALI/ARDS, miRNAs can regulate inflammatory and immune responses by targeting specific molecules. Regulation of miRNA expression can reduce damage and promote the recovery of ALI/ARDS. Consequently, miRNAs are considered as potential diagnostic indicators and therapeutic targets of ALI/ARDS. Given that inflammation plays an important role in the pathogenesis of ALI/ARDS, we review the miRNAs involved in the inflammatory process of ALI/ARDS to provide new ideas for the pathogenesis, clinical diagnosis, and treatment of ALI/ARDS. [ABSTRACT FROM AUTHOR]

A new asymmetric biphenyl dianhydride, 2-o-tert-butylphenoxy-4,4′,5,5′-biphenyltetracarboxylic dianhydride, was readily synthesized via a four-step route. The key intermediate, 2-nitro-bis(N-methylphthalimide) (2), was synthesized at low temperature (around 15°C), with a yield of over 90%, which enhances the molecular adjustment flexibility of the monomer. FT-IR and 1H-NMR were used to fully verify the proposed structure of this new asymmetric dianhydride. The polyimides were prepared from such new dianhydride and commercial diamines by high-temperature one step polymerization in m-cresol. The molecular structures of the polymers were determined by FT-IR and 1H-NMR. The inherent viscosities were in the range of 0.40-0.41. The polymers show high organosolubility in common solvents such as NMP, CHCl3 and THF. TGA analysis revealed that the polymers displayed good thermal stability up to 490°C. [ABSTRACT FROM AUTHOR]

Abstract: A novel thermal sensitive polyurethane (TSPU) membrane with a thermal switch was prepared via wet phase inversion technique and used for separation of NaCl, glycin from collagen solution. From Differential Scanning Calorimetry (DSC) and X-Ray Diffraction (XRD), it was found that the TSPU showed segmented structure (i.e. the hard segment and soft segment) and independent phase transition temperatures (the phase transition temperature of the soft segment defined as switch temperature, T s). Scanning Electron Microscope (SEM) and Atom Force Microscope (AFM) were employed to study the morphology structures of membranes, the results indicated that the membrane showed relative dense surfaces (or skin) and porous cross sections, which controlled their selectivity and permeation. The porosity of membrane measured by the mass loss of wet membrane after drying revealed that when the temperature varied ±10 °C around the T s, the porosity of membranes increased from 51.7% to 73.3%, showing a significant improvement to thermal stimuli. When this TSPU membrane was used for separation of NaCl, glycin from collagen solution, we found the ions of Na+ and Cl− could permeate the TSPU membrane at any temperature, and higher temperature resulted in higher penetration rate. Whilst the penetration of glycin relied on the temperature variation, that is, a barrier effect at lower temperature (T < T s) and higher permeation fluxes at higher temperature were observed. Typically, when the temperature exceeded the T s, the permeation flux of glycin increased markedly, showing sensitivity to thermal stimuli. Collagen, due to its large molecule size, could not permeate the TSPU membrane in all temperature range. As a result, molecules of NaCl, glycin and collagen with different size could be selectively separated by TSPU membrane driven by the temperature. [Copyright &y& Elsevier]

Abstract: A novel thermal-sensitive polyurethane (TSPU)/SiO2 nano-hybrid membrane was prepared via in situ nano-hybrid method in wet phase inversion process, and used for water vapor permeation. Atom force microscope (AFM) and scanning electron microscope (SEM) were used to observe the size scale and the distribution of nano-SiO2 throughout the TSPU matrix, and Fourier transform infrared (FTIR) spectroscopy was employed to reveal the nano-hybrid mechanism between TSPU and nano-SiO2. Simultaneously, differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis were used to investigate the phase separation behavior of the nano-composites and the influence of nano-SiO2 on the crystallization of the TSPU. Results from AFM and SEM analysis show that the mean size and the distribution of nano-SiO2 particles in the TSPU matrix is relied on the SiO2 content, i.e. SiO2 content lower than 5.0wt% result in homogeneously dispersed nano-SiO2 particles with a mean size below 100nm approximately throughout the TSPU matrix, while obvious SiO2 agglomerates (>1000nm) are in the overwhelming majority with excessive addition of SiO2 content into the TSPU resin. FTIR study indicates that two chemical bonds of Si–C and Si–O–C occur between the organic and the inorganic phase; one seems to be the reaction between nano-SiO2 and H–Ar (aromatic ring), and another is the condensation reaction between Si–(OH)4 produced by the hydrolysis of the nano-precursors (tetraethyoxyl silane) and the terminal HO–CH2– groups of the TSPU. Due to these interfacial interactions, the tensile strength and the broken elongation of nano-hybrid samples in the measurement of mechanical properties increase by 40.1% and 23.2%, respectively, as the SiO2 content rises from 0.00wt% to 5.0wt%. DSC study reveals that nano-hybridization does not disrupt the intrinsic phase-separated structure of the TSPU, but the phase transition temperature of soft segment (defined as switch temperature, T s) in TSPU increases slightly with the increase of nano-SiO2 content. XRD analysis indicates that appropriate amount of nano-SiO2 filled in the TSPU matrix is prone to induce the soft segment crystallization of the polymer. In addition, the water vapor permeability (WVP) of TSPU nano-hybrid membrane is found to depend on the size scale of SiO2 particles, which is relied on SiO2 content. To be specified, when nano-SiO2 particles with an average size of 100nm approximately are present in the TSPU matrix, the nano-hybrid samples show lower WVP at low temperatures and higher WVP at high temperatures than pure TSPU. Especially, when the temperature exceeds the T s, for example from 50°C to 60°C, the WVP of pure TSPU changes from 1026g/m2 day to 2200g/m2 day, whilst the WVP of the nano-hybrid TSPU with 5.0wt% SiO2 content changes from 995g/m2 day to 2927g/m2 day, the later shows more sensitive to thermal stimuli. [Copyright &y& Elsevier]

Abstract: The size and shape of free-volume holes available in membrane materials control the rate of gas diffusion and its permeability. Based on this principle, two segmented thermo-sensitive polyurethane (TSPU) membranes with functional gates, i.e. the ability to sense and respond to external thermo-stimuli, were synthesized and used for water vapor controllable permeation. Differential scanning calorimetry (DSC), positron annihilation lifetimes (PAL), water swelling and water vapor permeability (WVP) were used to evaluate how the structure of the polyurethane (PU) and the temperature influence the free-volume holes size and the water vapor permeability (WVP) of the PU membranes. DSC study reveals that TSPU with a glass transition or a crystalline transition reversible phase shows an obvious phase-separated structure and a phase transition temperature (defined as switch temperature, T s). PAL study indicates that the free-volume holes size of TSPU is closely related to the T s. When the temperature is higher than the T s, the ortho-positronium (o-Ps) lifetime (τ 3) and the average radius (R) of free-volume holes of TSPU membrane increase dramatically. As a result, the WVP of TSPU membrane shows a dramatic increase. Additionally, the water swelling and the WVP of TSPU membrane are found to depend on the inner structure of the polymer, and they also give different responses to temperature variation. When the temperature is higher than the T s, there is a significant increase of WVP from 3.80kg/m2 day to 7.63kg/m2 day for TSPU(a) and from 4.30kg/m2 day to 8.58kg/m2 day for TSPU(b), respectively. Phase transition accompanying significant changes in free-volume holes size and WVP can be used to develop “smart membranes” with functional gates and controllable gas permeation. [Copyright &y& Elsevier]

A core shell structure, large particle self-extinction acrylic resin emulsion is prepared by semi continuous feeding method through seed emulsion polymerization-three successive nucleation growth and shell polymerization. The effects of different feeding methods on the particle size of seed latex particles and the method of continuous growth of core latex particles are investigated. Simultaneously, the influence of latex particle size, core-shell structure and crosslinking degree on the extinction of acrylic resin coating is also sided. The results show that the seed latex particles with large particle size can be obtained by semi-continuous feeding method. By controlling the concentration of emulsifier and monomer, the nucleation mechanism is oligomer nucleation, and the growth of latex particles is dominant in the reaction, so as to outgain the seed latex particles with large Particle size (about 200 nm). After three times growth, the particle size of seed latex particles can reach about 700 nm. Finally after shell-shell polymerization, the particle size of coreshell latex is increased to about 800 nm. Latex particle size has an important influence on the gloss of the coating. Large latex particle size will produce rough microstructure on the coating surface and reduce the gloss of the coating, while the soft core-hard shell structure makes it difficult for latex particles to deform and integrate during film formation, leading to improve the roughness and extinction of the coating. At the same time, the shell density is also an important factor affecting the gloss of coating. After the introduction of crosslinking agent, the density of shell structure increases and the degree of freedom of polymer chains decreases, which retards the latex particles deform and fuse. As a result, the roughness of the coating surface is further increased, and the gloss of the PVC leather coating can be adjusted to 1.2°. [ABSTRACT FROM AUTHOR]

Owing to deep activation in biotissues and enhanced targeting efficiency, developing photoresponsive polymer‐upconversion nanoparticles (PP‐UCNPs) nanovectors has witnessed rapid growth in the past decade. However, up to date, all developed nanovectors require high‐order photon processes to initiate the release of cargos. The photodamage caused by high‐power near‐infrared laser light may be a critical obstacle to their clinical application. Here, for the first time, by leveraging absorption–emission spectral matching between donor–acceptor Stenhouse adducts (DASA) PP and UCNPs (λex, 808 nm) in the green region (≈530 nm), the designed nanovector is capable of releasing cargos at a low‐power 808 nm excitation (0.2 W). Considering the high molar absorptivity, biobenign, and synthetic tunability of DASA, DASA PP can be utilized as an up‐and‐coming candidate to design and synthesize the next generation of upconversion nanovectors without photodamage. [ABSTRACT FROM AUTHOR]

Passive radiative cooling technology has been widely concerned due to its merits of energy free and zero pollution. However, most of the radiative cooling materials are highly susceptible to contamination from solid dirt and rainwater, which greatly weak their cooling effectiveness. Herein, a hydrophobic radiative cooling composite coating, composed of polyurethane/polydimethylsiloxane (PU/PDMS) and modified hollow glass microsphere (MHGM), was fabricated through in situ reinforcing and phase separation processes. By the synergistic effect of MHGM filler and the surrounded microporous PU/PDMS matrix, the PU7/PDMS3-MHGM coating possessed strong solar reflectance and thermal emittance in the atmospheric transparency window of 0.906 and 0.961, respectively, resulting in sub-ambient daytime cooling of 8.1 °C and nighttime cooling of 3.9 °C. In addition, the composite coating exhibited a higher water contact angle of 139°, the dust and muddy water are unable to stain on its surface during the rinsing process, showing self-cleaning effect. More encouragingly, the composite coating still remained above 93.8 % passive radiative cooling efficiency even if after 100 cycles muddy water rinsing, certainly, such self-cleaning provides assurance for the sustainable application of radiative cooling coatings. [Display omitted] • PU7/PDMS3-MHGM coating was prepared via in situ reinforcing and phase separation processes. • PU7/PDMS3 polymer matrix with a mass ratio of 7/3 was optimized. • MHGM filler with polymer chains showed good dispersion level in the PU7/PDMS3 matrix. • PU7/PDMS3-MHGM possessed microporous polymer phase and hollow glass microsphere phase. • PU7/PDMS3-MHGM exhibited self-cleaning and durable passive radiative cooling behaviors. [ABSTRACT FROM AUTHOR]

The outbreak of coronavirus disease 2019 (COVID-19) has so far resulted in over a hundred million people being infected. COVID-19 poses a threat to human health around the world. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been confirmed as the pathogenic virus of COVID-19. SARS-CoV-2 belongs to the β-coronavirus family of viruses and is mainly transmitted through the respiratory tract. It has been proven that SARS-CoV-2 mainly targets angiotensin-converting enzyme II (ACE2) receptors on the surface of various cells in humans. The main clinical symptoms of COVID-19 include fever, cough, and severe acute respiratory distress syndrome (ARDS). Current evidence suggests that the damage caused by the virus may be closely related to the induction of cytokine storms in COVID-19. No specific drugs or measures have yet to be shown to cure COVID-19 completely. Cell-based approaches, primarily mesenchymal stem cells (MSCs), have been identified to have anti-inflammatory and immune functions in COVID-19. Clinical studies about using MSCs and its derivatives—exosomes for COVID-19 treatment—are under investigation. Here, we review the current progress of the biological characteristics, clinical manifestations, and cell-based treatment development for COVID-19. Providing up-to-date information on COVID-19 and potential MSC therapies will help highlight routes to prevent and treat the disease. [ABSTRACT FROM AUTHOR]

Crush injury is a disease that is commonly found in victims of earthquakes, debris flows, mine disasters, explosions, terrorist attacks, local wars, and other accidents. The complications that arise due to the crush injury inflicted on victims give rise to crush syndrome (CS). If not treated in time, the mortality rate of CS is very high. The most important measure that can be taken to reduce mortality in such situations is to immediately start treatment. However, the traditional treatment methods such as fluid resuscitation, diuresis, and hemodialysis are not feasible enough to be carried out at the disaster scene. So there is a need for developing new treatments that are efficient and convenient. Because it is difficult to diagnose in the disaster area and reach the treatment equipment and treat on time. It has become a new research needs to be directed into identifying new medical treatment targets and methods using the etiology and pathophysiological mechanisms of CS. In recent years, a large number of new anti-oxidant and anti-inflammatory drug therapies have been shown to be highly efficacious in CS rat/mouse models. Some of them are expected to become specific drugs for the emergency treatment of a large number of patients who may develop CS in the aftermath of earthquakes, wars, and other disasters in the future. Hence, we have reviewed the latest research on the medical therapy of CS as a source for anyone wishing to pursue research in this direction. [ABSTRACT FROM AUTHOR]

Anti-smudge coatings have attracted extensive attention in recent years owing to their hydrophobic, self-cleaning, anti-graffiti properties and so on. However, most of the anti-smudge coatings are solvent-based and cured at high temperature or using special curing equipment, which negatively impacts the environment and limits their large-scale application in daily life. Herein, we report a solvent-free anti-smudge coating with potential for large-scale and green manufacturing. In detail, polydimethylsiloxane (PDMS) was used as the hydrophobic component, (3-aminopropyl)triethoxysilane (APTES) and 3-glycidoxypropyltrimethoxysilane (GPTMS) were used as the cross-linking agent, and a solvent-free polyurethane (SFPU) anti-smudge coating was in-situ constructed at room temperature for 24 h without any curing equipment. Due to the enrichment of PDMS chains on the surface and the dense cross-linked network of the coating, the as-prepared coating not only exhibited a high contact angle for water (99.3 ± 1.5°) and diiodomethane (69.5 ± 0.9°), but also excellent anti-smudge to contaminants, with both water and oily liquids were easy to slide off the surface of the coating without leaving any traces. Even after writing with an oil-based marker, the ink on the coated surface could be easily wiped off. Further study reveals that the coating surface maintained its original liquid repellency and stain resistance even after 10 d immersion in a 10 wt% NaCl solution, showing durable anti-corrosion properties. In addition, pigments did not affect the anti-graffiti performance of the coating, providing a multi-color scheme for practical application. This convenient, low-energy, environmentally friendly anti-smudge coating has great potential for widespread application in industry and daily life. [Display omitted] • The coatings prepared by condensation of Si-OH and ring-opening reaction of epoxy • The coatings can be cured in 24 h at room temperature without any curing equipment. • The optimal polydimethylsiloxane (PDMS) content of the coating is 1 wt%. • The resulting coatings exhibit good anti-smudge and corrosion resistance. [ABSTRACT FROM AUTHOR]