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• The irreversible shrinkage of gelatin film caused by alternating dry-wet cycles. • Gelatin molecules produce intermolecular aggregation during dry-wet cycles. • Molecular conformation changes during intermolecular aggregation process. • Gelatin protein photos should be stored in a relatively stable humidity environment. The curling of historical photographs seriously endangers the information security and utilization value of image cultural heritage. Previous studies have shown that the shrinkage of emulsion gelatin in alternating dry-wet environment is the main cause of photo curling, while the mechanism of shrinkage is still unclear. In this work, the gelatin film samples with different shrinkage rates were firstly prepared through alternating dry-wet cycles. Then, Fourier-transform infrared spectroscopy (FTIR), UV–Vis-NIR spectroscopy, fluorescence spectrophotometer, static video contact angle meter, X-ray diffraction (XRD), scanning electron microscope (SEM), nuclear magnetic resonance (NMR) analyzer, X-ray photoelectron spectroscopy (XPS), circular dichroism (CD) spectrometer, and other instruments were used to analyze the morphology, hydrophilicity, structure, conformation and brittleness of gelatin films with different shrinkage changes. Finally, through the correlation between the molecular structure, surface characteristics and macroscopic properties of gelatin films were obtained, and the mechanism of the curling and brittle fracture caused by the change of gelatin properties under the dry-wet cycles was revealed. This study provides a scientific basis and experimental data for the preservation and restoration of historical photos based on gelatin. [Display omitted] [ABSTRACT FROM AUTHOR]

Study Objective: To determine the efficacy of using platelet-rich plasma (PRP) for vaginal wall repair in rats with vaginal wall impairment induced by vaginal distension (VD).Design: A single-blind, randomized study.Setting: A certified animal research facility.Animals: Twenty-four female Sprague Dawley rats.Interventions: Female Sprague Dawley rats were divided into sham (n = 8), VD (n = 8), and VD + PRP (n = 8) groups. Vaginal tissues from the VD group were dissected at 28-day post injury. VD + PRP rats received vaginal PRP injections on the 1st, 7th, 14th, and 21st day after VD and sacrificed on the 28th day.Measurements and Main Results: Urodynamic tests were performed in all rats. Immunohistochemistry was used to evaluate matrix metalloprotease-2 (MMP-2) and matrix metalloprotease-9 (MMP-9). Masson's staining was used to evaluate collagen fibers and calculate collagen volume fraction. Collagen fiber damage was confirmed in the VD group, evidenced by thinner and sparse distribution of collagen fibers, with significantly higher MMP-2 and MMP-9 expression than the sham group (p <.05). The collagen fiber damage in the vaginal wall likely led to pelvic floor dysfunction (PFD), evidenced by significantly decreased bladder leak-point pressure (p <.01) and abdominal leak-point pressure (p <.01) in the VD group compared with the sham group. After completion of the PRP treatment, a significantly higher collagen volume fraction (p <.01) and significantly increased bladder leak-point pressure (p <.05) and abdominal leak-point pressure (p <.01) were achieved in the VD + PRP compared with the VD group, thus indicating repair of the vaginal wall and improvement of PFD.Conclusion: PRP injections facilitate the regeneration of vaginal wall tissue, particularly collagen fiber, after VD, leading to functional improvement of PFD. Findings support the feasibility of using PRP as a novel treatment for PFD. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly pathogenic and contagious coronavirus that caused a global pandemic with 5.2 million fatalities to date. Questions concerning serologic features of long-term immunity, especially dominant epitopes mediating durable antibody responses after SARS-CoV-2 infection, remain to be elucidated. We aimed to dissect the kinetics and longevity of immune responses in coronavirus disease 2019 (COVID-19) patients, as well as the epitopes responsible for sustained long-term humoral immunity against SARS-CoV-2. We assessed SARS-CoV-2 immune dynamics up to 180 to 220 days after disease onset in 31 individuals who predominantly experienced moderate symptoms of COVID-19, then performed a proteome-wide profiling of dominant epitopes responsible for persistent humoral immune responses. Longitudinal analysis revealed sustained SARS-CoV-2 spike protein–specific antibodies and neutralizing antibodies in COVID-19 patients, along with activation of cytokine production at early stages after SARS-CoV-2 infection. Highly reactive epitopes that were capable of mediating long-term antibody responses were shown to be located at the spike and ORF1ab proteins. Key epitopes of the SARS-CoV-2 spike protein were mapped to the N-terminal domain of the S1 subunit and the S2 subunit, with varying degrees of sequence homology among endemic human coronaviruses and high sequence identity between the early SARS-CoV-2 (Wuhan-Hu-1) and current circulating variants. SARS-CoV-2 infection induces persistent humoral immunity in COVID-19–convalescent individuals by targeting dominant epitopes located at the spike and ORF1ab proteins that mediate long-term immune responses. Our findings provide a path to aid rational vaccine design and diagnostic development. [ABSTRACT FROM AUTHOR]

Strong coupling between autonomous transportation and production activities deeply influences planning and scheduling in smart factories, particularly in dynamic environments with rapid changes. This study addresses the dynamic flexible job shop schedule problem with transportation resources (DFJSPT) in which new job insertion, the most common unexpected event in a manufacturing system, is treated as a dynamic disturbance. A proactive-reactive methodology is adopted to respond to dynamic disturbances. Correspondingly, a two-stage multi-objective mixed-integer programming model is formulated for the proposed DFJSPT. In the initial scheduling stage, the model aims to minimize makespan and workload imbalance. In the rescheduling stage, instability minimisation is introduced to deal with the impact of the disturbance. To solve this complex problem, a multi-objective adaptive large neighbourhood search (MOALNS) algorithm is developed. Its novel heuristic operators supporting multi-objective optimization are designed to explore the neighbourhood of a solution. Moreover, the amount of domination between the solutions from the Archive is applied in the acceptance criteria. Overall, we validate the efficiency of the developed model and algorithm through a number of numerical experiments. The computational results verify the accuracy of the mathematical model and demonstrate the superiority of MOALNS in several aspects, including convergence, diversity, and the ability to search for high-quality solutions. In addition to its effectiveness, the algorithm is able to handle dynamic events flexibly, which makes it a suitable option for real-world applications of the DFJSPT. [ABSTRACT FROM AUTHOR]

In this work, a facile ratiometric fluorescence sensor for GSH measurement was designed based on MnO 2 nanosheet (NS), carbon dots (CDs), as well as a simple substrate o-phenylenediamine (OPD). Herein, MnO 2 NS played triple essential roles in the sensing system. First, it could be reduced by GSH through a special reaction, and therefore served as GSH recognizer. Second, it played as a fluorescence nanoquencher to strongly quench the fluorescence of CDs. Third, it could directly oxidize OPD to yield a luminescent product 2, 3-diaminophenazine (DAP) via the intrinsic oxidase-like activity. It revealed that MnO 2 NS could be reduced to Mn2+ in the presence of GSH. Thus its oxidase-like activity and fluorescence quenching abilities were inhibited, which then restricted the generation of DAP and recovered the fluorescence of CDs. Based on this phenomenon, a novel ratiometric fluorescence sensor for GSH determination was fabricated by measuring the ratio of fluorescent intensity of DAP to that of CDs. Besides, the constructed ratiometric fluorescent sensor, which could be facilely operated with single-wavelength excitation, exhibited high sensitivity and selectivity with a wider linear range and a lower detection limit. Image 1 • A facile single-wavelength excitation ratiometric fluorescence sensor was constructed for GSH. • MnO 2 nanosheets can not only effectively quench the fluorescence of CDs but also oxidize OPD into luminescent DAP due to its intrinsic oxidase-like activity. • DAP could also quench the fluorescence of CDs through the inner filter effect. [ABSTRACT FROM AUTHOR]

Abstract The organic crystal 4-chlorobenzaldehyde -N- methyl 4-stilbazolium tosylate (CMST) was grown from acetonitrile and methanol mixed solvent using slow cooling method for the first time. The optimum growth conditions based on different solution concentrations were investigated. The crystal atomic packing and bond length alternation (BLA) of CMST were identified through single crystal X-ray diffraction analysis, the calculated BLA value 0.1475 Å is close to optimum value for nonlinear optical (NLO) response. The composition and different functional groups of CMST compound were determined by 1H NMR and FT-IR studies. Moreover, the thermal stability and melting point were obtained through TG/DTG and DSC analyses. Important optical parameters such as optical transmittance, cut-off wavelength, absorption coefficient, band gap energy and refractive index were ascertained through UV–vis-NIR study, the low cut-off wavelength and wide optical transmittance of CMST crystal are favorable to optical device fabrication. The dielectric constant has been investigated. Green emission occurred at 521 nm was found through photoluminescence excitation study. These encouraging results suggest that the CMST crystal is a promising candidate for nonlinear optical device applications. [ABSTRACT FROM AUTHOR]

Abstract Antimicrobial peptides (AMPs) provide a promising solution to the serious threat of multidrug-resistant bacteria or superbugs to public healthcare, due to their unique disruption to bacterial membrane such as perforation. Unfortunately, the underlying action mechanism of AMPs, especially the possible transition between the membrane binding and perforation states of peptides (i.e., the classical two-state model), is still largely unknown. Herein, by combining experimental techniques with pertinent membrane models and molecular dynamic (MD) simulations, new insights into the intermediate states of the AMP melittin-membrane interaction process are obtained. Specifically, it is demonstrated that, after the initial binding, the accumulated melittin on the bilayer triggers vigorous fluctuation of the membrane and even extracts some lipid molecules exclusively from the deformed outer leaflet of the bilayer. Such a distinctive mass removal manner and the resultant local asymmetry in lipid number between the two leaflets change the mechanical status of the membrane and in turn reduce the free energy barrier for the melittin insertion. Finally, the formation of the transmembrane pores is facilitated significantly. These findings provide new insights into the complicated antimicrobial mechanisms of AMPs. Graphical abstract Unlabelled Image Highlights • Intermediate states during the melittin-induced membrane poration are observed. • Melittin-induced extraction of lipids occurs exclusively from the outer leaflet. • Asymmetry in membranes lowers the free energy barrier for melittin insertion. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Multi-lamellar lipid/nanoparticle membranesarefabricated viaco-assembly. • Si nanoparticles are orderly arrangedin themembranewith controllable separation. • The fluorescence properties of the Si nanoparticles are significantly modulated. Abstract Highly ordered self-assembly of nanoparticles (NPs) in a large scale promises attractive potential in optical modulation of the NPs for illuminating, imaging and sensing applications. In this work, a type of multi-lamellar nanocomposite membranes composed of phospholipid multilayers and Si NPs sandwiched between each adjacent lipid layers was fabricated via a facile co-assembly method. X-ray reflectivity (XRR), grazing incident X-ray diffraction (GIXRD) and TEM measurements verified the highly ordered arrangement of NPs within the multilayers with a controlled in-plane inter-particle separation from ∼7 nm to ∼14 nm. Due to such an arrangement, the photoluminescence (PL) properties of the Si NPs were effectively modulated. Compared to the NPs in suspension or its pure film, the PL of the NPs in the membranes blue-shifted and remarkably narrowed, with the full-width-at-half-maximum (FWHM) value reduced from >110 nm of the pure Si NP film to below 43 nm. The radiative lifetime of the NPs was also significantly reduced from ∼16.7 ns to ∼3.3 ns depending on the inter-particle distance in the membrane. Meanwhile, the Si NPs within membranes maintained robust photostability under UV irradiation. [ABSTRACT FROM AUTHOR]

Biomimetic channels based on carbon nanotubes (CNTs) with fast and selective transport have attractive applications in many fields. In this work, a remarkable and modulated enhancement in the ion transport rate through CNTs is facilitated by means of lipid decoration, by a factor of up to 20 times. A type of CNT membrane is firstly prepared, composed of well aligned multi-wall carbon nanotubes with an inner size of ∼10 nm. An inter-diffusion method is used to efficiently incorporate lipids within the CNTs. It is found that the lipid phase state as well as the surface property of the tubes' inner walls corporately determine the assembly behavior, such as location and stability of lipids, which further influence the ion transport rate through the tubes. For example, the incorporation and self-assembly of liquid-phase DOPC and polymerized Diyne-PC within the tubes induces an enhancement in steady ion transport rate through CNTs by a factor of 5 and 20 times, respectively. In contrast, the gel-phase DPPC prefers to stay at tube tips, which increases the ion transport rate during the initial stage only. This work provides a practical guide to regulate the ion transport behaviors through CNTs for versatile applications. [ABSTRACT FROM AUTHOR]

In this study, a novel carboxymethyl dextran (CMD)-based dual drug delivery system that delivering two water insoluble drugs to tumor sites was developed and evaluated for anticancer activities. Paclitaxel (PTX) and docosahexaenoic acid (DHA) were covalently coupled with CMD to generate CMD-DHA-PTX conjugate S and conjugate L with different linkers containing amino acids Gly-Gly or Lys-Gly-Gly, respectively. Both conjugates possessed high PTX loading contents and enhanced water solubility, as well as the ability of being self-assembled into nanoparticles with the nanoparticle size ranged from 88.7 nm to 94.7 nm. These two conjugates released free PTX continuously in plasma and cancer cells. The conjugate S exhibited improved pharmacokinetic parameters and higher distribution extent in tumor sites than the parent PTX, Abraxane and the conjugate L. The antitumor efficacy of these two conjugates outperformed parent PTX formulation and Abraxane in nude mice bearing breast cancer cells MCF-7. More importantly, the conjugate S treatment eliminated all the xenograft tumors without causing any mice body weight loss in mice model. This study revealed that the dextran-based dual drug conjugates may represent an effective and innovative way to deliver anticancer agents to a variety of tumors. [Display omitted] • Dual drug conjugates were fabricated by coupling dextran with paclitaxel and DHA. • The conjugates showed great water solubility and enhanced pharmacokinetic profiles. • The conjugates selectively accumulated in tumor. • The conjugates exhibited more potency than both parent paclitaxel and Abraxane. • The conjugate with short linker eradicated all MCF-7 tumors bearing in nude mice. [ABSTRACT FROM AUTHOR]

Biomembrane transformations are closely related to many biological processes including endo/exocytosis and the cellular response to the local physical environment. In this work, we investigated the transformation between lipid membranes and lipid vesicles/tubes modulated by the solid substrate of graphene oxide (GO) aggregates under laser irradiation. We firstly fabricate a novel type of lipid@GO composite consisting of micrometer-sized GO aggregates surrounded by lamellar lipid membranes. Upon laser irradiation, lipid protrusion occurs and leads to the formation of vesicles adsorbed on the GO aggregate surface, with an average size as 0.43 times of the radius of GO aggregate. Both the location and the dynamic formation process of vesicles can be modulated. The arising of vesicles prefers to occur at edges of the GO planes rather than on surface of individual GO sheets within the GO aggregate. Furthermore, at a reduced laser power density, the lipid protrusion mainly grows to tubes instead of vesicles. Such transformations from lipid membrane to vesicles and tubes is ascribed to the reduction of GO to reduced-GO (rGO) under laser irradiation, probably along with the release of gases leading to the deformation of lipid membrane surrounding the GO surface. [ABSTRACT FROM AUTHOR]

The response of cell membranes to the local physical environment significantly determines many biological processes and the practical applications of biomaterials. A better understanding of the dynamic assembly and environmental response of lipid membranes can help understand these processes and design novel nanomaterials for biomedical applications. The present work demonstrates the directed assembly of lipid monolayers, in both liquid and gel phases, on the surface of a monolayered reduced graphene oxide (rGO). The results from atomic force microscopy indicate that the hydrophobic aromatic plane and the defect holes due to reduction of GO sheets, along with the phase state and planar surface pressure of lipids, corporately determine the morphology and lateral structure of the assembled lipid monolayers. The DOPC molecules, in liquid phase, probably spread over the rGO surface with their tails associating closely with the hydrophobic aromatic plane, and accumulate to form circles of high area surrounding the defect holes on rGO sheets. However, the DPPC molecules, in gel phase, prefer to form a layer of continuous membrane covering the whole rGO sheet including defect holes. The strong association between rGO sheets and lipid tails further influences the melting behavior of lipids. This work reveals a dramatic effect of the local structure and surface property of rGO sheets on the substrate-directed assembly and subsequent phase behavior of the supported lipid membranes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two-step catalytic pyrolysis characteristic of microalgae over ZSM-5 was studied. • High selectivities of N-heterocyclic compounds and hydrocarbons were achieved. • Two-step catalytic pyrolysis reaction pathways of microalgae was presented. To explore an effective method of utilizing nitrogen-rich microalgae, the two-step pyrolysis (TSP) characteristic of Nannochloropsis sp (NCS) over ZSM-5 were studied by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and thermogravimetric analyzer (TG). The results showed that the TG process of NCS was classified into three stages. ZSM-5 increased the final weight loss and the pyrolysis temperature of NCS. The kinetic analysis was conducted by Flynn-Wall-Ozawa method, and showed that the pyrolysis of NCS conformed to one-dimensional shrinking core model. ZSM-5 did not affect the kinetic model, but decreased the activation energy. Compared with one-step pyrolysis, TSP improved the selectivity of N-heterocyclic compounds in the first step. Catalytic TSP further reduced the complexity of products significantly, and increased the selectivity of olefins in the first step, nitriles and aromatic hydrocarbons in the second step. The possible catalytic TSP reaction pathways of NCS were proposed. [ABSTRACT FROM AUTHOR]

Alcoholic ketoacidosis (AKA) lacks specific clinical presentation. The results of blood testing commonly show hemoconcentration, elevated β-hydroxybutyrate levels, and acidosis in patients with AKA. Herein, we report a case of AKA accompanied by hyperglycemia and review the related literature. Case report: AKA associated with hyperglycemia is rare, and its pathogenesis is similar to that of diabetic ketoacidosis, thereby making differentiation challenging. Accordingly, AKA is easily misdiagnosed by endocrinologists. The main symptoms of a 37-year-old female included hyperglycemia, elevated β-hydroxybutyrate levels, and metabolic acidosis. Primary clinical presentations were severe nausea and vomiting. The patient initially diagnosed with DKA were eventually confirmed as AKA, who recovered after active therapy with rehydration and correction of hyperglycemia, electrolyte imbalance, and ketosis. This study provides a reference for clinicians to reduce missed diagnosis and the misdiagnosis rates of AKA. [ABSTRACT FROM AUTHOR]

The dynamic interactions between drug carrier molecules and a cell membrane can not be ignored in their clinical use. Here a simple, label-free and non-invasive approach, photo-voltage transient method, combined with the atomic force microscopy, dynamic giant unilamellar vesicle leakage assay and cytotoxicity method, was employed for a real-time monitoring of the interaction process. Two representative polymer molecules, polyoxyethylene (35) lauryl ether (Brij35) and polyvinylpyrrolidone (PVPk30), were taken as examples to interact with a phospholipid bilayer membrane in a low ionic strength and neutral pH condition. Brij35 demonstrated an adsorption-accumulation-permeabilization dominated process under the modulation of polymer concentration in the solution. In contrast, PVPk30 performed a dynamic balance between adsorption-desorption of the molecules and/or permeabilization-resealing of the membrane. Such difference explains the high and low cytotoxicity of them, respectively, in the living cell tests. Briefly, through combining the photo-voltage approach with conventional fluorescent microscopy method, this work demonstrates new ideas on the time and membrane actions of polymer surfactants which should be taken into account for their biomedical applications. [Display omitted] • The dynamic membrane action of Brij/PVP was monitored in a simple and real-time way. • A synergy of photo-voltage transients, AFM, GUV leakage and cell tests was used. • Brij35 shows a concentration-dependent adsorption-permeabilization process. • PVPk30 performs a dynamic adsorption-desorption balance with lower cytotoxicity. [ABSTRACT FROM AUTHOR]

This work proposes a fluorescent probe that uses coumarin as a chromophore and NBD as a sensing unit to detect hydrogen sulfide. The probe can work well in aqueous media, and can quickly respond to hydrogen sulfide. When detecting hydrogen sulfide, the probe has high selectivity and good anti-interference ability. Besides, in monitoring hydrogen sulfide in living cells and zebrafish, good results have demonstrated the probe's potential in practical applications. A fluorescent probe that uses coumarin as a chromophore and NBD as a sensing unit to selectively and instantaneously was developed to detect hydrogen sulfide in living cells and zebrafish. [Display omitted] • This probe exhibited high selectivity and strong anti-interference ability in detecting hydrogen sulfide. • This probe was successfully used for imaging endogenous and exogenous H 2 S in living cells. • The successful detection of H 2 S in zebrafish proves that this probe can perform well in biological imaging. [ABSTRACT FROM AUTHOR]

The construction of semiconductor heterojunction is considered an effective strategy to improve photocatalytic performance in degrading organic pollutants. Herein, the ZnO/Bi 2 WO 6 (ZBW) heterostructures were prepared by hydrothermal method, and the photocatalytic properties of the samples were evaluated by degrading methylene blue (MB) under ultraviolet light irradiation. The obtained ZBW heterostructures exhibit superior photocatalytic activity to pure ZnO and Bi 2 WO 6. The photocatalytic efficiency of ZBW is 97.95%, and the total organic carbon removal of MB is 95.48% after 120 min irradiation. Recycling experiments show that ZBW maintains good photocatalytic activity and stability after four cycles of use. Electron paramagnetic resonance and free radical capture experiments demonstrate that the photogenerated holes are the primary active group of the photocatalytic reaction, whereas hydroxyl and superoxide radicals play smaller roles. The formation of ZBW heterojunction in the composite promotes the separation of photogenerated electrons and holes, greatly improving the photocatalytic performance of the material. [ABSTRACT FROM AUTHOR]

Abstract Hierarchical UiO-66 and its amino-analogue UiO-66-NH 2 nanocrystals were successfully synthesized by introducing a suitable amount of water into the conventional synthesis of UiO-66/UiO-66-NH 2 without the need for a chelating agent, surfactant or aging. The hierarchical porous qualities and particle sizes of the UiO-66/UiO-66-NH 2 products can be facilely tuned by the amounts of water. Hierarchical UiO-66/UiO-66-NH 2 nanocrystals exhibited significantly enhanced adsorption capacity for dyes and catalytic activity in esterification/Knoevenagel reactions compared to the microporous UiO-66/UiO-66-NH 2. This facile synthetic strategy offers a new alternative way to prepare UiO materials with the combination of hierarchical and functional property. Graphical abstract Image 1 Highlights • H 2 O-induced nanocrystal-formation strategy to the controllable synthesis of hierarchically structured UiO-66 nanocrystals was put forward. • The hierarchical porous qualities and particle sizes of the UiO-66/UiO-66-NH 2 products can be facilely tuned by the amounts of water. • Hierarchical UiO-66/UiO-66-NH 2 nanocrystals exhibited significantly enhanced adsorption capacity for dyes and catalytic activity in esterification/knoevenagel reactions. [ABSTRACT FROM AUTHOR]