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AbstractBackgroundMethodsResultsConclusionsIn healthcare settings, Central Venous Catheter-Associated Bloodstream Infections (CVC-BSIs) present a serious problem since they raise morbidity, mortality, and medical expense rates. The management of these illnesses is made more challenging by the development of antimicrobiotic resistance. Nanotechnology has attracted interest recently as a viable method for creating new antimicrobial agents. By putting antibacterial nanomaterials onto the catheter’s appear, that may reduce the likelihood of getting sick by stopping germs from adhering and growing. Antimicrobial additives can be released gradually finishes, protecting over time through bioengineering sectors. To prevent and treat CVC-BSIs, this study will assess the efficacy of antimicrobial medicines based on nanoparticles.In the network Meta-Analyses (MA) and Systematic Review (SR), we looked for studies published from January 2010 to September 2021 using the Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, MEDLINE, CINAHL, and Web of Science databases. Ten papers in all were included in the review following the screening of the publications using inclusion and exclusion criteria.In contrast to conventional catheters, the implementation of Antimicrobial Catheters (AC) and the use of chlorhexidine (CHG) or Silver Sulfadiazine (SS) demonstrated notably reduced occurrences of Central Venous Catheter-Associated Bloodstream Infections (CVC-BSIs) per 1000 Catheter Days (CD) (with Odds Ratios (ORs) and 95% Credibility Intervals (CrIs) of 0.66 and 0.54, respectively) by bioengineering sectors. Moreover, these interventions were linked to the lowest rate of Catheter Colonization (CC), with ORs as well as 95% CrIs of 0.45 and 0.31, respectively, underscoring their potential as effective strategies for minimizing the risk of infections associated with catheter use as well as bioengineering sectors innovations.As a result, CVC-BSI has shown significant promise for prevention and treatment with nanoparticle-based antimicrobial medicines. Due to their special characteristics and modes of action, they are strong candidates for improving the security and effectiveness of central venous catheter use in clinical settings. Due to ongoing research and development in this area, nanoparticle-based coatings and therapies may be used to lessen the impact of CVC-BSIs and enhance patient outcomes. [ABSTRACT FROM AUTHOR]

Key message: We explored the phylogenomics and methylomics of NLR genes in 41 plant species and found that highly duplicated plant NLR genes are hyper methylated in non-CG context. [ABSTRACT FROM AUTHOR]

Satellite clock bias is the key factor affecting the accuracy of the single point positioning of a global navigation satellite system. The traditional model back propagation (BP) neural network is prone to local optimum problems. This paper presents a prediction model and algorithm for the clock bias of the BP neural network based on the optimization of the mind evolutionary algorithm (MEA), which is used to optimize the initial weights and thresholds of the BP neural network. The accuracy of the comparison between clock bias data is verified with and without one-time difference processing. Compared with grey model (GM (1,1)) and BP neural network, this paper discusses the advantages and general applicability of this method from different constellation satellites, different atomic clock type satellites, and the amount of modeling data. The accuracy of the grey model (GM(1,1)), BP, and MEA-BP models for satellite clock bias prediction is analyzed and the root mean square error, range difference error, and the mean of the clock bias data compared. The results demonstrate that the prediction accuracy of the three satellites significantly increased after one-time difference processing and that they have good stability. The prediction accuracy of four sessions of 2 h, 3 h, 6 h, and 12 h obtained using the MEA-BP model was better than 0.74, 0.80, 1.12, and 0.87 ns, respectively. The MEA-BP model has a specific degree of improvement in the prediction accuracy of the different sessions. Additionally, the prediction accuracy of different models has a specific relationship with the length of the original modeling sequence, of which BP model is the most affected, and MEABP is relatively less affected by the length of the modeling sequence, indicating that the MEA-BP model has strong anti-interference ability. [ABSTRACT FROM AUTHOR]

Interaction is the main feature of social media, while in recent years, frequent privacy disclosure events of the social media user affect users' privacy disclosure behavior. In this paper, we explore the mechanism of interaction characteristics by social media apps on users' privacy disclosure behavior. Using SOR theoretical models and the privacy calculus theory, the effects of privacy disclosures on TikTok are examined. Structural equation modeling is used to analyze the data from 326 questionnaires. We concluded that human–computer interaction (perceived personalization, perceived control) and interpersonal interaction (perceived similarity) positively and negatively affected perceived benefits and perceived risks, respectively, and had positive effects on intention to disclose privacy through perceived benefits and perceived risks, respectively, except that perceived personalization had no effect on perceived risk and intention to disclose privacy. In addition, perceived benefits and perceived risks played an intermediary role in interactivity and privacy disclosure intention. Finally, we provided countermeasures and suggestions for social media operators and policy makers. [ABSTRACT FROM AUTHOR]

In the face of tight natural resources and complex as well as volatile environments, and in order to meet the pressure brought by population growth, we need to overcome a series of challenges. As a new data management paradigm, the Earth Observation Data Cube simplifies the way that users manage and use earth observation data, and provides an analysis-ready form to access big spatiotemporal data, so as to realize the greater potential of earth observation data. Based on the Open Data Cube (ODC) framework, combined with analysis-ready data (ARD) generation technology, the design and implementation of CDC_DLTool, extending the support for data loading and the processing of international and Chinese imagery data covering China, this study eventually constructs the China Data Cube (CDC) framework. In the framework of this CDC grid, this study carried out case studies of water change monitoring based on international satellite imagery data of Landsat 8 in addition to vegetation change monitoring based on Chinese satellite imagery data of GF-1. The experimental results show that, compared with traditional scene-based data organization, the minimum management unit of this framework is a pixel, which makes the unified organization and management of multisource heterogeneous satellite imagery data more convenient and faster. [ABSTRACT FROM AUTHOR]

The lateral flow immunoassay (LFIA) is widely employed as a point-of-care testing (POCT) technique. However, its limited sensitivity hinders its application in detecting biomarkers with low abundance. Recently, the utilization of nanozymes has been implemented to enhance the sensitivity of LFIA by catalyzing the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB). The catalytic performance of nanozymes plays a crucial role in influencing the sensitivity of LFIA. The Cornus officinalis Sieb. et Zucc-Pd@Pt (CO–Pd@Pt) nanozyme with good peroxidase-like activity was synthesized herein through a facile one-pot method employing Cornus officinalis Sieb. et Zucc extract as a reducing agent. The morphology and composition of the CO–Pd@Pt nanozyme were characterized using TEM, SEM, XRD, and XPS. As a proof of concept, the as-synthesized CO–Pd@Pt nanozyme was utilized in LFIA (CO–Pd@Pt-LFIA) for the detection of human chorionic gonadotropin (hCG). Compared to conventional gold nanoparticles-based LFIA (AuNPs-LFIA), CO–Pd@Pt-LFIA demonstrated a significant enhancement in the limit of detection (LOD, 0.08 mIU/mL), which is approximately 160 times lower than that of AuNPs-LFIA. Furthermore, experiments evaluating accuracy, precision, selectivity, interference, and stability have confirmed the practical applicability of CO–Pd@Pt-LFIA for hCG content determination. The present study presents a novel approach for the synthesis of bimetallic nanozymes through environmentally friendly methods, utilizing plant extracts as both protective and reducing agents. Additionally, an easily implementable technique is proposed to enhance signal detection in lateral flow immunoassays. [Display omitted] • The extract of Cornus officinalis Sieb. et Zucc fruits was used as a reducing agent to synthesize CO–Pd@Pt nanozyme. • The as-synthesized CO–Pd@Pt nanozyme exhibits good peroxidase-like activity. • The CO–Pd@Pt nanozyme can be applied in LFIA (CO–Pd@Pt-LFIA) to detect the concentration of hCG with a LOD of 0.08mIU/mL. [ABSTRACT FROM AUTHOR]

The electric field-induced shape transition of a nanodroplet confined in a silicon nanogroove with variable structure was investigated through molecular dynamics simulations. Our work provides insight into the relationship between the shape transition and the molecular interaction. We demonstrated that the geometric structure of the groove significantly influences the responsive behaviors of the droplet to the electric field. The simulations elucidate increasing the tilt angle of the groove reduces the critical field strength for the shape transition of the droplet under parallel electric field. Above the critical field, the droplet detaches from the groove and forms a liquid bridge across the groove, leading to weakened interfacial interactions. The detachment process of the droplet from the rectangular groove, which originates from the spreading of water molecules on perpendicular side walls, is different from the droplet initially confined in the groove with tilt angle higher than 90°. Under the perpendicular electric field, the droplet undergoes various shape transitions depending on the groove structure. In particular, the droplet in the groove with a moderate opening forms two asymmetrical liquid columns. The retraction behavior of the droplet in the groove with the small opening sheds light on the competition between interfacial interactions. The shape transition of droplets in the electric field due to the change of confinement nanostructures, such as liquid bridge, asymmetrical extension, branching and merging, is helpful to enrich the understanding of electrowetting and confinement dynamics of the droplets. [Display omitted] • A liquid bridge forms across the groove above critical parallel electric field. • The droplet in rectangular groove undergoes asymmetrical detachment process. • Geometric confinement influences orientational polarization of water molecules. • The droplet shows branching and merging shape under perpendicular electric field. [ABSTRACT FROM AUTHOR]

The development of nanomaterials that mimic oxidase-like activities has recently attracted an increasing amount of attention. Obtaining highly active and cost-effective oxidase mimics has posed a significant challenge in this area of research. In this study, we successfully synthesized nickel-doped ferrous disulfide nanocubes (Ni–FeS 2) via a facile one-step method. Characterization by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that Ni was predominantly distributed within the surface layer of the Ni–FeS 2 nanocubes. The incorporation of nickel in density functional theory (DFT) calculations effectively reduced the d-band center of Fe, resulting in weakened adsorption to intermediates and thereby enhancing its catalytic efficiency. Moreover, we developed a novel approach based on Ni–FeS 2 (the Ni–FeS 2 method) for detecting reducing substances, which exhibited good sensitivity toward ascorbic acid (AA), glutathione (GSH), and cysteine (Cys). Remarkably, the established Ni–FeS 2 method was successfully employed for in vitro assessment of total antioxidant capacity (TAC) in cellular and organ samples, thereby enabling discrimination between normal, senescent, and malignant cells as well as distinguishing among healthy liver tissue, cancerous liver tissue, and metastatic organs. [Display omitted] [ABSTRACT FROM AUTHOR]

A hydroxyapatite (HA) biofunctional gradient coating (BFGC) was prepared on the surface of Ti6Al4V alloy via laser cladding. The effect of the laser power on the properties of the resulting BFGC was evaluated, where the surface morphology and phase distribution of the samples were observed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The wear and corrosion properties of the BFGC samples were studied in simulated body fluid (SBF), and the proliferation of MC3T3-E1 osteoblasts on the surface of the BFGC samples was investigated using an in vitro cell proliferation assay. The surface quality of the BFGC samples initially improved with increasing laser power, where a smooth, dense and crack-free coating surface with a compact interface and tight bonding to the substrate was achieved at 700 W. However, laser powers of 800 W and higher compromised the coating. A strong diffraction peak related to CaTiO 3 was observed on the surface of the BFGC samples after laser cladding, while HA deposition was observed on the surface of the coating after immersion in SBF for 30 days. The BFGC samples exhibited excellent wear resistance and corrosion resistance, and were conducive to the proliferation of osteoblasts without cytotoxicity. Overall, this laser cladding BFGC shows promise for enhancing the wear resistance, corrosion resistance and biocompatibility of titanium alloy implants, where the best coating performance was achieved at a laser lap ratio of 50%, scanning speed of 1 cm/s, and laser power of 700 W. [ABSTRACT FROM AUTHOR]

Rationale: Forgetting of fear memory is a current medical therapy for posttraumatic stress disorder (PTSD), and hippocampal long-term depression (LTD) may be the underlying mechanism. Neuregulin 1 (NRG1), a trophic factor, reportedly modulates memory consolidation and synaptic plasticity. Methods: Fear memory was assessed using contextual fear conditioning. Electrophysiology was used to measure LTD and GABAergic transmission in the hippocampus. Objectives: To determine the contribution of hippocampal NRG1 to fear memory forgetting and low-frequency stimulation (LFS)–induced LTD. Results: Administration of NRG1 in the hippocampus accelerated forgetting of contextual fear memories. Furthermore, NRG1 had no effect on low-frequency stimulation–induced LTD in young mice but significantly facilitated the induction of LTD and GABAergic transmission in adult animals. More importantly, NRG1-facilitated LTD induction in adult mice could be blocked by inhibition of GABAA receptors and NMDAR activation. Conclusion: These findings suggest a role for NRG1 in fear memory forgetting and hippocampal LTD, providing a potential target for the development of drug-assisted PTSD therapy. [ABSTRACT FROM AUTHOR]

This study examines molecular interactions between two nanodroplets locating on the graphene monolayer and their morphological transition under the electric field parallel to the monolayer surface by using molecular dynamics simulations. The effects of the electric field and the salt concentration on the transmitted interactions, droplet shape and microscopic structure of interfacial water are elucidated in detail. It was found that the electric field can boost the electrostatic interaction between two pure water (PW) droplets, but weaken the short-range LJ interaction. The electric field with low strength mainly causes separation of two droplets rather than changes their shapes. There is a faster response of microscopic structures of water molecules to strong electric field than the morphological change of droplets, leading to a transition of the interaction energy from strong to weak. The salt concentration in the salty water (SW) droplets has negligible effect on the interaction energy in the absence of electric field. At strong electric field, the break-up behaviors of the SW droplets depend on the salt concentration. Simulation results reveal that the transmitted interactions between the PW and SW droplets as well as two SW droplets significantly affect the break-up behaviors and morphological transition of the droplets. • Electric field boosts electrostatic interaction between two pure water droplets. • Transmitted short-range interaction through the graphene monolayer is negligible in the presence of electric field. • Break-up behaviors of salty water droplets depend on salt concentration and transmitted interactions. [ABSTRACT FROM AUTHOR]

• Ferritin BfrB and heat-shock protein GrpE were used to construct a novel vaccine. • Adjuvanted BG stimulated strong cellular and humoral immune responses in mice. • BG + MH vaccine significantly protected mice against M. tb H37Ra and H37Rv infection. • BG + MH enhanced the survival of mice after M. tb H37Rv infection, better than BCG. • Our findings inform the selection of antigens and the optimize vaccination regimens. Tuberculosis poses a significant threat to human health due to the lack of an effective vaccine. Although promising progress has been made in the development of tuberculosis vaccines, new vaccines that broaden the antigenic repertoire need to be developed to eradicate this illness. In this study, we used Mycobacterium tuberculosis ferritin BfrB and heat-shock protein GrpE to construct a novel multi-antigenic fusion protein, BfrB-GrpE (BG). BG protein was stably overexpressed in the soluble form in Escherichia coli at a high yield and purified via sequential salt fractionation and hydrophobic chromatography. Purified BG was emulsified in an adjuvant containing N, N'-dimethyl-N, N'-dioctadecylammonium bromide, polyinosinic-polycytidylic acid, and cholesterol (DPC) to construct the BG/DPC vaccine, which stimulated strong cellular and humoral immune responses in mice. Moreover, combination of BG with our previously developed vaccine, Mtb10.4-HspX (MH), containing antigens from both the proliferating and dormant stages, significantly reduced the bacterial counts in the lungs and spleens of M. tuberculosis -infected mice. Importantly, mice that received BG + MH/DPC after M. tuberculosis H37Rv infection survived slightly better (100% survival) than those that received the BCG vaccine (80% survival), although the difference was not statistically significant. Our findings can aid in the selection of antigens and optimization of vaccination regimens to improve the efficacy of tuberculosis vaccines. [ABSTRACT FROM AUTHOR]

Cassava starch, a sort of cheap and easily purchased material, whose main components from nature can be recycled without causing environmental and workpiece pollution, is applied in abrasive flow machining (AFM) processing to obtain a fine finish on internal surfaces efficiently. The cassava starch medium with the concentration of cassava starch more than 37% has the characteristics of order-dependence of magnitude increase in viscosity, and its rheological properties are investigated to prepare shear thickening polishing slurry (STP-s). Subsequently, a theoretical model is developed to reveal the material removal behavior in the processing based on the theory of Archard sliding wear and fluid dynamics, and the maximum error between theoretical and experimental values is 13.1%. Processing experiments prove that using cassava starch medium can achieve low roughness (∼20 nm Ra) of the workpiece. Besides, the temperature which causes a change in the rheological curve plays a crucial role in processing efficiency. When the temperature of STP-s exceeds 50 ℃, the ability of efficient finishing is basically lost. Observation experiments show that the micro-processing mechanism of AFM processing is friction and wear by the clusters action coming from shear thickening behavior. The processing capability using the cheap cassava starch medium is, for the first time, achieved in internal surface finishing and indicates the precision processing prospect in other finishing techniques. [Display omitted] [ABSTRACT FROM AUTHOR]

We study the electrokinetic transport behavior of water molecules and ions in hydrophobic graphene nanochannels with variable surface charge densities as well as the interfacial water structure based on detailed molecular dynamics simulations. The interfacial water structure, described by the water density, hydrogen bonding, diffusion, distribution of the OH bond and dipole orientations, is strikingly influenced by the surface charge sign and density. We find anomalous electrokinetic effects which are related to the distribution of counterions close to the surface, ion-specific effects and the interfacial water structure. On a negatively charged graphene layer, the attraction of Na + ions towards the surface enhances the interfacial friction. In contrast, if the surface is positively charged, high surface charge density triggers an anomalous enhancement of electroosmotic flow, accompanied by an abrupt change of the interfacial water structure. At high surface charge densities, the mobility of the interfacial water at the positively charged surfaces is suppressed more strongly compared to the negatively charged surface. Our results reveal new electrokinetic phenomena by the comparison of negatively and positively charged surfaces. [ABSTRACT FROM AUTHOR]

ABSTRACT We perform multiscale simulations based on the coupling of molecular dynamics and lattice-Boltzmann (LB) method to study the electrohydrodynamics of a polyampholyte-grafted spherical nanoparticle. The long-range hydrodynamic interactions are modeled by coupling the movement of particles to a LB fluid. Our results indicate that the net-neutral soft particle moves with a nonzero mobility under applied electric fields. We systematically explore the effects of different parameters, including the chain length, grafting density, electric field, and charge sequence, on the structures of the polymer layer and the electrophoretic mobility of the soft particle. It shows that the mobility of nanoparticles has remarkable dependence on these parameters. We find that the deformation of the polyampholyte chains and the ion distribution play dominant roles in modulating the electrokinetic behavior of the polyampholyte-grafted particle. The enhancement or reduction in the accumulation of counterions around monomers can be attributed to the polymer layer structure and the conformational transition of the chains in the electric field. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 1435-1447 [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is characterized by the formation of Lewy bodies (LBs) in the brain. These LBs are primarily composed of α‐Synuclein (α‐Syn), which has aggregated. A recent report proposes that CCAAT/enhancer‐binding proteins β (C/EBPβ) may act as an age‐dependent transcription factor for α‐Syn, thereby initiating PD pathologies by regulating its transcription. Potential therapeutic approaches to address PD could involve targeting the regulation of α‐Syn by C/EBPβ. This study has revealed that Nrf2, also known as nuclear factor (erythroid‐derived 2)‐like 2 (NFE2L2), suppresses the transcription of C/EBPβ in SH‐SY5Y cells when treated with MPP+. To activate Nrf2, sulforaphane, an Nrf2 activator, was administered. Additionally, C/EBPβ was silenced using C/EBPβ‐DNA/RNA heteroduplex oligonucleotide (HDO). Both approaches successfully reduced abnormal α‐Syn expression in primary neurons treated with MPP+. Furthermore, sustained activation of Nrf2 via its activator or inhibition of C/EBPβ using C/EBPβ‐HDO resulted in a reduction of aberrant α‐Syn expression, thus leading to an improvement in the degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc) in mouse models induced by 1‐methyl‐4‐phenyl‐1,2,5,6‐tetrahydropyridine (MPTP) and those treated with preformed fibrils (PFFs). The data presented in this study illustrate that the activation of Nrf2 may provide a potential therapeutic strategy for PD by inhibiting the abnormal C/EBPβ/α‐Syn signaling pathway. [ABSTRACT FROM AUTHOR]

Key message: We analyzed the evolutionary pattern of cysteine-rich peptides (CRPs) to infer the relationship between CRP copy number and plant ecotype, and the origin of bi-domains CRPs. Plants produce cysteine-rich peptides (CRPs) that have long-lasting broad-spectrum antimicrobial activity to protect themselves from various groups of pathogens. We analyzed 240 plant genomes, ranging from algae to eudicots, and discovered that CRPs are widely distributed in plants. Our comparative genomics results revealed that CRP genes have been amplified through both whole genome and local tandem duplication. The copy number of these genes varied significantly across lineages and was associated with the plant ecotype. This may be due to their resistance to changing pathogenic environments. The conserved and lineage-specific CRP families contribute to diverse antimicrobial activities. Furthermore, we investigated the unique bi-domain CRPs that result from unequal crossover events. Our findings provide a unique evolutionary perspective on CRPs and insights into their antimicrobial and symbiosis characteristics. [ABSTRACT FROM AUTHOR]

Abstract The wetting effect and related applications of nanodroplets have attracted extensive research interest. In this work, we report molecular dynamics simulations of the confinement dynamics of nanodroplets at different droplet-surface interactions, surface separations, and ion concentrations under the electric field. The results show that in the case of a single droplet, there is a critical value of surface wettability for the shape transition of the confined droplet. Below this value, the droplet shrinks into a spherical shape and attaches to the surface. Above this value, the droplet splits into two smaller droplets which locate at the bottom and top surfaces, respectively. For the two-droplet cases, a liquid bridge forms and some ions migrate into the pure water droplet under the electric field. The results reveal that the ion concentration has a significant effect on the shape evolution of droplets. The stable morphology of droplets under the electric field depends on the droplet-surface interactions as well as the ion concentration. We explore the underlying mechanisms causing the morphological transition by analyzing the intermolecular interactions and interfacial characteristics. [ABSTRACT FROM AUTHOR]

We study the conformational behavior of spherical brushes composed of polyampholyte chains end-grafted onto spherical particles in the presence of monovalent and tetravalent counterions using molecular dynamics simulations. The overall net charge for each chain consisting of both positively and negatively charged segments is zero. The dependences of the structural properties of the brushes on the chain stiffness, grafting density and charge sequence along the chains are examined systemically. For the diblock brushes, our results indicate that increasing the chain rigidity leads to a significant effect of counterion valence and a reduced collapsing degree of the brushes. At high chain stiffness, the number of high-valent counterions trapped in the brushes is diminished compared to the cases with monovalent counterions, corresponding to lower osmotic pressure. For the flexible brushes, the short-range and electrostatic interactions depending on the charge sequence, determine the conformational transition of the brushes, whereas the effect of counterion valence becomes weaker. In the presence of high-valent counterions, the brushes which consist of polyampholyte chains with blocks of medium length, adopt a slightly stretched conformation owing to relatively strong electrostatic correlation between high-valent counterions and oppositely charged monomers. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the feasibility, safety, and clinical efficacy of CT-guided 125I seed interstitial brachytherapy in patients with recurrent spinal metastases after external beam radiotherapy (EBRT). Between August 2003 and September 2015, 26 spinal metastatic lesions (24 patients) were reirradiated by this salvage therapy modality. Treatment for all patients was preplanned using a three-dimensional treatment planning system 3–5 days before 125I seed interstitial brachytherapy; dosimetry verification was performed immediately after seed implantation. Median actual D90 was 99 Gy (range, 90–176), and spinal cord median Dmax was 39 Gy (range, 6–110). Median local control (LC) was 12 months (95% CI: 7.0–17.0). The 6- and 12-month LC rates were 52% and 40%, respectively. Median overall survival (OS) was 11 months (95% CI: 7.7–14.3); 6-month and 1-, 2-, and 3-year OS rates were 65%, 37%, 14%, and 9%, respectively. Pain-free survival ranged from 2 to 42 months (median, 6; 95% CI: 4.6–7.4). Treatment was well-tolerated, with no radiation-induced vertebral compression fractures or myelopathy reported. Reirradiation with CT-guided 125I seed interstitial brachytherapy appears to be feasible, safe, and effective as pain relief or salvage treatment for patients with recurrent spinal metastases after EBRT. [ABSTRACT FROM AUTHOR]

ABSTRACT By means of Langevin molecular dynamics simulations, we study the packaging dynamics of flexible and semiflexible polyelectrolytes in spherical cavities that resemble viral capsids. We employ a coarse-grained model of the polymer-capsid complex that allows us to perform simulations of a 900mer and investigate the influence of surface charges inside the capsid and an additional motor force, acting on the polymer in the portal region of the cavity, on the packaging process. Our results indicate that it is most efficient if surface charges are present that initially promote the formation of an ordered surface layer inside the capsid. Once these charges are screened, the motor force pulls in the remaining part of the chain. Additionally, the simulations also demonstrate that the packaging dynamics depends on the counterion valence. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 1054-1065 [ABSTRACT FROM AUTHOR]

• Heteroatom substitutions influence photochromic property of diarylethene derivatives. • New heteroatom substituted diarylethene were theoretically studied by DFT/TD-DFT. • Optical absorptions could be finely tuned by heteroatom groups in UV-vis region. • Se substitutions probably have better thermal bistability and photochomic properties. Photochromic diarylethene derivatives are one of the most promising candidates for various applications in optoelectronic devices. The heteroatom substitution of the aryl groups of diarylethene derivatives could greatly influence their optical properties and thermal stability. For example, the diarylethene derivatives with two thiophene rings (Dithienylethenes) have longer absorption wavelength, better fatigue resistance, sensitivity and thermal bistability than those with two furan rings. To further understand the influence of the heteroatom substitution in aryl rings, a series of diarylethene derivatives with different heteroatoms in IV (C, Si, Ge), V (N, P, As), and VI groups (O, S, Se) of Periodic Table were theoretically explored with DFT/TD-DFT functionals. According to the predicted results, the substituent effects of increasing atomic weights could influence the optical properties, the relative energies, the thermal bistability of the open isomer and the closed isomers. The maximum optical absorptions of the closed isomers and the open isomers could be finely tuned by these heteroatom groups in visible region of 395∼522 nm and in ultraviolet region of 300∼341 nm, respectively. The diarylethene with Se substituent diarylethene was predicted to have the best thermal bistability of all the nine substitutions and also have comparable photochomic properties than widely-used S diarylethene (Dithienylethenes). As 6π-electron system is indispensable part for nearly all known diarylethene derivates, the study probably provides a useful guideline for the future design of novel Se substituent diarylethene compounds with tunable photochromic properties and improved thermal bistability. : A series of diarylethene derivatives with different heteroatoms in IV (C, Si, Ge), V (N, P, As), and VI groups (O, S, Se) of Periodic Table were theoretically explored with DFT/TD-DFT functionals. Optical properties could be finely tuned by heteroatom groups in UV-vis region. The diarylethene with Se substituent diarylethene was predicted to have the best thermal bistability of all the nine substitutions and also have comparable photochomic properties with widely-used dithienylethenes. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights: [•] The LPE chain develops various wrapping conformations around the SPB. [•] The complexation degree shows strong dependence on the core radius. [•] Various conformational binding modes for the LPE–nanoparticle complex are identified. [ABSTRACT FROM AUTHOR]

• The mathematical models between processing parameters and groove width/depth are established by response surface methodology. • The groove surface is wavy accumulation due to the sputtering of liquid phase material. • The hydrophilicity of laser patterned magnesium alloy is enhanced due to the increase of surface free energy and roughness. • After laser patterning, the corrosion area between sample and corrosive medium is enlarged, and its corrosion resistance is reduced. Parallel groove patterns were fabricated on ZK60A magnesium alloy surface using nanosecond laser technology. In order to study the influence of laser processing parameters on the groove size, firstly, the single factor test was used to preliminarily determine the range of laser parameters, and then the mathematical models between processing parameters and groove width (W), depth (D) were established by response surface methodology. The morphologies, elements, hardness and phases of the magnesium alloy with different scanning distances were characterized by lanthanum hexaboride scanning electron microscope (SEM), environmental SEM, microhardness tester and X-ray diffractometer (XRD), respectively. The electrochemical corrosion performances of polished and laser patterned magnesium alloy samples in hanks' balanced salt solution (HBSS) were analyzed and compared using electrochemical experiments. The results show that W first increases and then decreases with the decrease of laser scanning speed (v) or the increase of repetition frequency (f), while D shows an increasing trend; the regression model obtained by the response surface methodology is in good agreement with the experimental values, and it accurately predicts the groove size. The wavy accumulation on the groove surface is caused by the sputtering of liquid materials when the laser acts on the sample surface. Compared with the polished sample, the hardness of samples with scanning distances of 80, 120 and 160 μm is significantly improved, which are 40.30, 30.69 and 29.18% respectively. E corr values of polished sample and patterned samples with scanning distances of 80, 120 and 160 μm are −1.4481, −1.6398, −1.5712 and −1.5142 V, respectively; and the corresponding I corr values are 5.2209 × 10–6, 1.2378 × 10–5, 2.7849 × 10–5 and 6.3782 × 10–6 A•cm−2, respectively. The hydrophilicity of laser patterned magnesium alloy is enhanced, which is conducive to cell adhesion, however, the probability of contact between corrosive medium and samples increases at the same time. In addition, the grain refinement increases crystal defects, thereby reducing the corrosion resistance of laser patterned samples. [ABSTRACT FROM AUTHOR]

• Transmission of molecular interactions through graphene can drive migration of droplets. • Enhancing electric field accelerates migration velocity of two droplets towards each other. • Dipole–dipole interactions of interfacial water enhance deflection of water dipoles. • Critical electric field to induce large deformation becomes lower for cases of two droplets. Understanding the physical mechanism of wetting transparency of monolayer graphene, or how atoms or molecules located on opposite sides of the atomically thin carbon monolayer transmit molecular interactions (such as van der Waals and electrostatic forces) is of significant importance for many extraordinary applications from scientific and practical perspectives. In the current work, we carried out molecular dynamics simulations to explore the interactions between two droplets (TD) separated by the monolayer graphene under applied electric field. The results indicate that in the absence of the electric field the transmission of molecular interactions can drive migration of two droplets towards each other, implying partial wetting transparency of the graphene. Compared to the cases of single droplet (SD), the critical electric field to induce large deformation is lower for the TD cases. However, the droplet–droplet interactions under strong electric fields suppress the reduction of the number of water molecules in the graphene/droplet interface and the elongation of droplets. To understand the enhancement of interactions between two droplets owing to the electric field, we analyze microscopic structures of interfacial water (dipole orientation distribution and hydrogen bonding). The dipole–dipole interaction through the graphene mainly contributes to the droplet–droplet interactions. It was found that significant deflection of water dipoles for the TD cases occurs as the electric field enhances, but the deflection for the SD cases is smaller and even the droplet is detached from the graphene surface. Our findings provide fundamental insights on the influence of the electric field on molecular interactions between two droplets through the monolayer graphene and clues for developing potential graphene-based nanofluidic applications controlled by external electric field. [ABSTRACT FROM AUTHOR]

A molecular dynamics study of the electrophoresis of bottle-brush polyelectrolytes (BPEs) through nanochannels is reported. The BPE molecules consist of a neutral backbone with charged side chains. For strong attractive interactions between the BPE and the wall, the BPE is being trapped on the channel surface. A stretching-shrinking migration of the BPE in a channel of radius 6 σ is observed at relatively strong electric fields. The stretching-shrinking transition is periodic for intermediate electric fields but not for stronger electric fields. The BPE also shows a transverse migration toward the wall at weak electric fields, while toward the center with further enhancing the electric field. For a channel with larger radius 12 σ, the BPE does not migrate in the stretching-shrinking manner. [ABSTRACT FROM AUTHOR]

This is the first study to explore the risk factors for nephropathy caused by gadolinium-based contrast agents and establish a prediction model to identify high-risk patients. A total of 1404 patients who received gadolinium-based contrast agents in our hospital were included. The participants were randomly assigned in a 7:3 ratio to the modeling and validation groups. The modeling group was divided into a contrast-induced nephropathy group and a non-contrast-induced nephropathy group. The clinical characteristics before the use of contrast agents were compared between the two groups. The risk factors for contrast-induced nephropathy were analyzed by logistic regression. A nomogram that could predict the incidence of contrast-induced nephropathy was plotted. The validation group was used to verify the predictive model. The incidence of contrast-induced nephropathy caused by gadolinium-based contrast agents was 3.92% (55/1404). The logistic stepwise regression analysis showed that sex, systolic pressure (SBP), absolute neutrophil count, albumin, fasting blood glucose level, and furosemide use were significant predictors of contrast-induced nephropathy caused by gadolinium-based contrast agents. The above predictors were then included in the nomogram construction. The area under the receiver operating characteristic (ROC) curve was 0.82 (p < 0.001). The specificity and sensitivity corresponding to the optimal cutoff point (0.039) based on the area under the ROC curve were 71.9% and 80.5%, respectively. Sex, SBP, absolute neutrophil count, albumin, fasting blood glucose levels, and furosemide use are significant predictors of contrast-induced nephropathy caused by gadolinium-based contrast agents. Therefore, the incidence of contrast-induced nephropathy may be estimated by the prediction model established in this study before the use of contrast agents. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations were performed for electro-osmotic flow (EOF) confined in a polyelectrolyte-grafted nanochannel under variable grafting density and normal electric field. With decreasing the value of the normal electric field, the brush undergoes a collapse transition, and the ion distribution is changed significantly. The brush thickness increases on increasing the grafting density at positive and weak negative electric fields, whereas a reduced brush thickness is observed at strong negative electric field. Our results further reveal that the flow velocity is not only dependent on conformational transition of the brush but also related to the cation and anion distributions. At low grafting density, the EOF is almost completely quenched at high electric field strength due to strong surface friction between ions and walls. For the case of very dense grafting, the flow velocity is influenced weakly within the brush when varying the grafting density. Additionally, a bidirectional flow occurs at an intermediate electric field. The investigation on fluid flux indicates that the fluid flux is insensitive to the grafting density, when the normal electric field is removed. For nonzero normal electric fields, a significant change in the fluid flux is observed at low grafting densities. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 [ABSTRACT FROM AUTHOR]

A hybrid particle–continuum method is used to study the shear flow confined between two opposing walls, one of which is coated with polymer chains. Molecular dynamics (MD) is used in the particle region near the brush and Navier–Stokes (NS) equations are applied in the remaining region where the continuum assumption holds. The information exchange from the continuum region to the particle region is implemented using the constrained particle dynamics. Both Couette shear flow and oscillatory flow are considered in the present work. The effect of the shear flow on the conformational characteristics of polymer brushes is analyzed. In the overlap region, the velocities obtained from MD simulations are smoothly connected with those from NS equations. Our investigations demonstrate that the hybrid particle–continuum model is valid in exploring the shear behavior of polymer brushes. [ABSTRACT FROM AUTHOR]

We report a molecular dynamics study on non-equilibrium dynamics of polyelectrolyte brushes under external electric fields. In this work, the effects of chain stiffness and salt concentration on static and dynamic responses of the brushes are addressed in detail. Our simulations indicate that varying these parameters induce rich electro-responsive behavior of the brushes. The increase of salt concentration results in the enhancement of an opposite electric field formed by non-equilibrium distribution of cations and anions, which resists stretching or shrinkage of grafted chains. At strong positive electric fields, the flexible brushes are more sensitive to the change of salt concentration. When reversing the electric field, the stiff brushes undergo a conformational transition from collapse to complete stretching. At high salt concentrations, dynamic responsive magnitude of the brush thickness to added electric field is strongly reduced. It was found that the fall time for the stiff brush becomes much shorter than that for the flexible brush. Additionally, increasing ion concentration leads to an excess extension or shrinkage of flexible brushes. For strongly stiff brushes, such phenomenon occurs in the presence or absence of salt. [ABSTRACT FROM AUTHOR]

We report molecular dynamics simulations on bottle-brush polyelectrolytes end-grafted to a planar surface. For each bottle-brush polyelectrolyte, flexible charged side chains are anchored to one neutral main chain. The effects of the counterion valence and the grafting density on the density profiles and the structural characteristics of the brush were studied in this work. It is found that the electrostatic repulsion between charged monomers in the side chains leads an extended conformation of the brush in a solution containing monovalent counterions, while strong electrostatic binding of multivalent counterions to the side chains has a significant contribution to the collapse of the brush. For the trivalent case, the distribution of end monomers in the main chains becomes broader upon decreasing the grafting density, as compared with the monovalent case. However, the position of the distribution for the monovalent case is relatively insensitive to the change of the grafting density. Additionally, with increased counterion valence, enhanced electrostatic correlation between counterions and charged side chains also weakens the diffusive ability of counterions. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 [ABSTRACT FROM AUTHOR]

Recently, various types of hollow materials have been added into polymer matrices to improve the gas permeation and separation performance of polymer materials. In this study, hollow polyimide (PI) nanoparticles with microporous shells were synthesized by interfacial polymerization between 4,4-(9-fluorenylidene)-dianiline and 1,2,4,5-benzenetetracarbonyl tetrachloride in the microemulsion. Free-standing polydimethylsiloxane (PDMS)/hollow PI nanoparticles mixed matrix membranes were prepared and the gas permeation-separation performance was investigated. The hollow and porous structure of the nanoparticles was well-preserved in membranes, which reduced the mass transport resistance. The permeability firstly increased and then decreased as the nanoparticle loading increased without sacrificing the permselectivity. Compared to the neat PMDS membranes with O 2 and CO 2 permeability of 786 and 3484 Barrer, respectively, the mixed matrix membranes with 3 wt% hollow PI nanoparticles achieved a O 2 permeability up to 1664 Barrer accompanied with an O 2 /N 2 permselectivity of 2.3 and a CO 2 permeability up to 6639 Barrer accompanied with a CO 2 /N 2 permselectivity of 9.1 at 35 °C and 0.2 MPa. Mixed-matrix composite membranes were fabricated by dip-coating the porous polyetherimide substrate into a PDMS solution with 3 wt% nanoparticles. The resultant defect-free mixed-matrix composite membrane showed excellent O 2 and CO 2 permeances of up to 1677 and 6502 GPU, respectively. The air separation measurement showed that the composite membranes could produce oxygen-enriched permeate stream enriched to ca. 30 vol%. [Display omitted] • Doping hollow PI nanoparticles into PDMS increased permeabilities by over 90%. • Permeabilities increased without sacrificing the permselectivity of MMMs. • The defect-free composite mixed matrix membrane was fabricated by dip-coating. • The O 2 permeance of composite membranes was 1677 GPU and that of CO 2 was 6502 GPU. • In a one-stage air separation module, O 2 was concentrated to 30% at permeate side. [ABSTRACT FROM AUTHOR]

The mechanisms governing the electrocoalescence between droplets are intricate owing to the presence of many influential parameters. In this work, we conduct molecular dynamics simulations to explore the effects of electric field strength and ionic concentration on the electrocoalescence behaviors of one pure water droplet and one salty droplet. The dynamic evolution is difierent from that for two identical droplets. The electric field strengths are chosen near the critical value. When the electric field strength is less than the critical value, the coalescence process is similar regardless of the ionic concentration of the salty droplet. The analysis on the mobility of ions demonstrates that the diffusion time of ions is much longer compared to the characteristic time of deformation of the coalesced droplet. At a stronger electric field than the critical field, the coalescence behavior exhibits dependence on the ionic concentration. For cases of high ionic concentrations, a rebounding behavior between two droplets is identified due to aggregation of ions close to the contact region of the droplets. Further, we also investigate molecular interaction energy, hydrogen bonding and ejection of daughter droplets during the electrocoalescence. Our study reveals that the coupling effect between the electric field and the ionic concentration plays an important role in controlling the electrocoalescence behavior of droplets. • Mechanisms of electrocoalescence between pure water and salty droplets are explored. • Coupling effect between electric field and ionic concentration plays a critical role. • Remarkable inconsistency between ion diffusion and droplet deformation is identified. [ABSTRACT FROM AUTHOR]

Sulfate is a critical component of schwertmannite. However, the sulfate content of schwertmannite decreases with the increase in AMD-polluted river pH value, and its impact on the surface properties and Cr(VI) adsorption of schwertmannite remains unclear. To address this issue, different methods, including batch adsorption, N 2 physisorption, scanning electron microscopy (SEM), potentiometric titration, X-ray photoelectron spectroscopy (XPS), attenuated total reflectance–Fourier transform infrared spectroscopy (ATR-FTIR) in combination with two-dimensional correlation spectroscopy (2D-COS) analysis, and surface complexation modeling (SCM) were employed. Our results showed that sulfate existed as both non-protonated bidentate-binuclear complexes and non-protonated outer-sphere complexes in schwertmannite. The surface morphology and particle size of schwertmannite were unaffected by the sulfate content. However, a decrease in sulfate content resulted in a drop in the negative charge on the surface of schwertmannite, which is conducive to particle aggregation. An increase in pH, on the other hand, raised the negative charge and encouraged the dispersion of the particles. And then, reducing the sulfate content of schwertmannite led to a decrease in acid-base buffer and Cr(VI) adsorption capacity of schwertmannite. The adsorption process of Cr(VI) by schwertmannite can be divided into two stages. In the first stage, Cr(VI) was adsorbed primarily through anion exchange reactions with the sulfate; however, the contribution of surface complexation gradually increased as the initial sulfate content decreased because of a reduced likelihood of anion exchange and an increase in the specific surface area of schwertmannite. Additionally, the behavior of sulfate and Cr(VI) in this stage could be predicted based on the initial sulfate content of schwertmannite. In the second stage, surface complexation with hydroxyl sites became the predominant mechanism of adsorption, which still exhibited great potential at higher Cr(VI) concentrations. Finally, the aforementioned hypothesis was used to establish a CD-MUSIC model, and the fitting results demonstrated that the density and Cr(VI) adsorption capacity of the sulfate site dropped as the sulfate content decreased, while the hydroxyl site was less impacted. The findings have provided insights into further understanding the properties of schwertmannite and its adsorption of Cr(VI). [ABSTRACT FROM AUTHOR]

[Display omitted] • Conductive hydrogels prepared by electrohydrodynamic printing exhibit enhanced conductivity. • Ion-electron conductive hydrogel with MXene co-ILs composite conductive network. • Hydrogel exhibited good mechanical properties, excellent sensing performance, and high frost resistance. • Hydrogel-based flexible strain sensor for human motion detection and information transmission. Conductive hydrogels with high performance and frost resistance are essential for flexible electronics, electronic skin, and soft robots. Nonetheless, the preparation of hydrogel-based flexible strain sensors with rapid response, wide strain detection range, and high sensitivity remains a considerable challenge. Furthermore, the inevitable freezing and evaporation of water in sub-zero temperatures and dry environments lead to the loss of flexibility and conductivity in hydrogels, which seriously limits their practical application. In this work, ionic liquids (ILs) and MXene are introduced into gelatin/polyacrylamide (PAM) precursor solution, and a PAM/gelatin/ILs/MXene/glycerol (PGIMG) hydrogel-based flexible strain sensor with MXene co-ILs ion–electron composite conductive network is prepared by combining the electrohydrodynamic (EHD) printing method and in-situ photopolymerization. The introduction of ILs provides an ionic conductive channel for the hydrogel. The introduction of MXene nanosheets forms an interpenetrating network with gelatin and PAM, which not only provides a conductive channel, but also improves the mechanical and sensing properties of the hydrogel-based flexible strain sensor. The prepared PGIMG hydrogel with the MXene co-ILs ion–electron composite conductive network demonstrates a tensile strength of 0.21 MPa at 602.82 % strain, the conductivity of 1.636 × 10−3 S/cm, high sensitivity (Gauge Factor, GF = 4.17), a wide strain detection range (1–600 %), and the response/recovery times (73 ms and 74 ms). In addition, glycerol endows the hydrogel with excellent freezing (−60 °C) and water retention properties. The application of the hydrogel-based flexible strain sensor in the field of human motion detection and information transmission shows the great potential of wearable devices, electronic skin, and information encryption transmission. [ABSTRACT FROM AUTHOR]

We study the conformational behavior of spherical polyelectrolyte brushes in the presence of monovalent and trivalent counterions in a confined environment. The confinement is exerted by two parallel walls on the brushes. The enhancement of the confinement induces the extension of grafted chains. For the monovalent case, the increase of the charge fraction leads to extended brush conformation for different slit width (distance between two walls) but collapsed brush in the presence of trivalent counterions is observed. The confinement does not affect electrostatic correlation between trivalent counterions and charged monomers. However, it was found that narrow slit width contributes to stronger electrostatic correlation for the monovalent case. This is because more monovalent counterions are inside the brush at strong confinement, but almost all trivalent counterions are trapped into the brush independently of the slit width. The diffusion of counterions under the confinement is related to the electrostatic correlation. Our simulations also reveal that the brush thickness depends on the slit width nonlinearly. [ABSTRACT FROM AUTHOR]

Adenosylmethionine decarboxylase 1 (AMD1) is a key enzyme involved in biosynthesis of polyamines including spermidine and spermine. The potential function of AMD1 in human gastric cancers is unknown. We analyzed AMD1 expression level in 319 human gastric cancer samples together with the adjacent normal tissues. The protein expression level of AMD1 was significantly increased in human gastric cancer samples compared with their corresponding para-cancerous histological normal tissues (P < 0.0001). The expression level of AMD1 was positively associated with Helicobactor pylori 16sRNA (P < 0.0001), tumor size (P < 0.0001), tumor differentiation (P < 0.05), tumor venous invasion (P < 0.0001), tumor lymphatic invasion (P < 0.0001), blood vessel invasion (P < 0.0001), and tumor lymph node metastasis (TNM) stage (P < 0.0001). Patients with high expression of AMD1 had a much shorter overall survival than those with normal/low expression of AMD1. Knockdown of AMD1 in human gastric cancer cells suppressed cell proliferation, colony formation and cell migration. In a tumor xenograft model, knockdown of AMD1 suppressed the tumor growth in vivo. Inhibition of AMD1 by an inhibitor SAM486A in human gastric cancer cells arrested cell cycle progression during G1-to-S transition. Collectively, our studies at the cellular, animal and human levels indicate that AMD1 has a tumorigenic effect on human gastric cancers and affect the prognosis of the patients. [ABSTRACT FROM AUTHOR]

Objective: Significant progress has been made in recent years in the diagnosis of periprosthetic joint infections (PJI). However, the lack of a gold standard test for the diagnosis of PJI remains a challenge.The aim of this study was to evaluate the diagnostic values of the albumin/fibrinogen ratio (AFR), the C‐reactive protein/albumin ratio (CAR), and the levels of fibrinogen (FIB) and albumin (ALB) in the diagnosis of PJI. Methods: The medical records of 158 patients who had undergone hip or knee revisions from January 2018 to May 2022 were retrospectively analyzed. Of these patients, 79 were diagnosed with PJI, while 79 were diagnosed with aseptic loosening (AL). PJI was defined using the Musculoskeletal Infection Society criteria. The plasma levels of C‐reactive protein (CRP), ALB, and FIB; the erythrocyte sedimentation rate (ESR); and the AFR and CAR in the two groups were recorded and analyzed. The receiver operating characteristic curve was used to calculate the sensitivity and specificity of each indicator; the diagnostic value for each indicator was calculated as the area under the curve (AUC). Results: The ESR, CRP, FIB, and CAR values in the PJI group were significantly higher than those in the AL group, and the ALB and AFR values were significantly lower than those in the AL group (p < 0.001). The AUC values of AFR and fibrinogen were 0.851 and 0.848, respectively, which were slightly higher than those of CRP (0.826) and ESR (0.846). The AUC of CAR was 0.831 which was slightly lower than that of CRP (0.846). ALB had an AUC of 0.727. The optimal threshold, sensitivity, and specificity, respectively, were 10.05, 84.81%, and 82.28% for AFR; 4.03 μg/mL, 77.22%, and 86.08% for FIB; 0.23, 72.15%, and 82.28% for CAR; and 37.30 g/L, 65.82%, and 73.42% for ALB. Conclusions: AFR, CAR, and FIB are good new auxiliary diagnostic indicators of PJI, while ALB is of fair value for the diagnosis of PJI. [ABSTRACT FROM AUTHOR]

Duchenne muscular dystrophy (DMD) is a severe, progressive, muscle-wasting disease, characterized by progressive deterioration of skeletal muscle that causes rapid loss of mobility. The failure in respiratory and cardiac muscles is the underlying cause of premature death in most patients with DMD. Mutations in the gene encoding dystrophin result in dystrophin deficiency, which is the underlying pathogenesis of DMD. Dystrophin-deficient myocytes are dysfunctional and vulnerable to injury, triggering a series of subsequent pathological changes. In this review, we detail the molecular mechanism of DMD, dystrophin deficiency-induced muscle cell damage (oxidative stress injury, dysregulated calcium homeostasis, and sarcolemma instability) and other cell damage and dysfunction (neuromuscular junction impairment and abnormal differentiation of muscle satellite). We also describe aberrant function of other cells and impaired muscle regeneration due to deterioration of the muscle microenvironment, and dystrophin deficiency-induced multiple organ dysfunction, while summarizing the recent advances in the treatment of DMD. [ABSTRACT FROM AUTHOR]

Synergistic palladium/copper catalysis for asymmetric allylic alkylation of vinylethylene carbonates with aldimine esters has been developed for the synthesis of α-quaternary (Z)-trisubstituted allylic amino acids under mild conditions. This methodology features broad substrate compatibilities in yields of up to 87% and up to 94% ee. A facile scale-up and straightforward conversion to 1,2,3,5-tetrasubstituted pyrrole and 1,2,5,6-tetrahydropyridine bearing chiral quaternary carbon centers verifies the synthetic utility of this method. [ABSTRACT FROM AUTHOR]

A basic understanding of the transport mechanisms of nanostructures in a polymer brush-modified nanochannel as well as the brush-nanostructure interactions at molecular level is important to design and fabricate emerging smart nano/microfluidic channels. In this work, we report coarse-grained molecular dynamics simulations of the translocation of nanoparticles through a cylindrical nanochannel coated with the polymer brush. The effects of the interparticle interaction and grafting density on the distribution and electrokinetic transport of nanoparticles are addressed in detail. Analysis of the distribution and velocity profiles of nanoparticles from the simulations indicate that the location of nanoparticles along the radial direction and their migration velocity are very sensitive to the change of interparticle interaction. We find complicated transport dynamics of nanoparticles under the influence of various grafting densities. The nanoparticles show markedly different translocation behavior upon increasing the grafting density, which depends on the counterion distribution, free room within the brush, nanoparticle-polymer friction, and brush configuration. Our results may serve as a useful starting point for the transport of nanostructures in polymer-modified channels and help to guide the design of novel smart nanofluidic channels for controlling the migration behavior of nanostructures. [ABSTRACT FROM AUTHOR]

Coarse-grained molecular dynamics simulations are used to investigate physical deposition behavior of charged amphiphlic diblock copolymers. The effects of solvent selectivity, charge distribution in amphiphlic diblock copolymers, and electric field strength on deposition conformations are studied qualitatively. Flat amphiphilic bilayers, which consist of hydrophilic monolayer and hydrophobic brush, are formed by physical deposition of charged amphiphlic diblock copolymers in nonselective solvents. For physically deposited amphiphlic diblock copolymers in selective solvents, amphiphilic bilayers consist of disc-shaped hydrophilic monolayers and hydrophobic nanospheres are found. This study sheds light on the formation of various amphiphlic diblock copolymer deposition conformations in different solvents and interaction mechanism of different components. Furthermore, the evolution of physical deposition process of charged amphiphlic diblock copolymers layer offers new insight to the controlling of amphiphilic bilayer thickness, hydrophobic nanosphere size, and interface property of depositional amphiphlic diblock copolymers. [ABSTRACT FROM AUTHOR]

The effective and strong adherence of silver nanoparticles (AgNPs) to the substrate surface is pivotal to the practical application of those AgNPs-modified materials. In this work, AgNPs were synthesized through a green and facile hydrothermal method. Chitosan was introduced as the binding agent for the effective loading of AgNPs on activated carbon fibers (ACF) surface to fabricate the antibacterial material. Apart from conventional instrumental characterizations, i. e., scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), zeta potential and Brunauer-Emmett-Teller (BET) surface area measurement, molecular dynamics simulation method was also applied to explore the loading mechanism of AgNPs on the ACF surface. The AgNPs-loaded ACF material showed outstanding antibacterial activity for S. aureus and E. coli . The combination of experimental and theoretical calculation results proved chitosan to be a promising binding agent for the fabrication of AgNPs-loaded ACF material with excellent antibacterial activity. [ABSTRACT FROM AUTHOR]

Identifying novel molecules involved in axon regeneration of neurons in the peripheral nervous system (PNS) will be of benefit in obtaining a therapeutic strategy for repairing axon damage both in the PNS and the central nervous system (CNS). Metabolism and axon regeneration are tightly connected. However, the overall metabolic processes and the landscape of the metabolites in axon regeneration of PNS neurons are uncovered. Here, we used an ultra high performance liquid tandem chromatography quadrupole time of flight mass spectrometry (UHPLC‐QTOFMS)‐based untargeted metabolomics to analyze dorsal root ganglia (DRG) metabolic characteristics at different time points post sciatic nerve injury and acquired hundreds of differentially changed metabolites. In addition, the results reveal that several metabolic pathways were significantly altered, such as ‘Histidine metabolism’, ‘Glycine serine and threonine metabolism’, ‘Arginine and proline metabolism’, ‘taurine and hypotaurine metabolism’ and so on. Given metabolite could alter a cell's or an organism's phenotype, further investigation demonstrated that N, N‐dimethylglycine (DMG) has a promoting effect on the regenerative ability post injury. Overall, our data may serve as a resource useful for further understanding how metabolites contribute to axon regeneration in DRG during sciatic nerve regeneration and suggest DMG may be a candidate drug to repair nerve injury. [ABSTRACT FROM AUTHOR]

The aim of this study is to probe the possible molecular mechanisms underlying the effects of propofol on HT22 cells. HT22 cells treated with different concentrations were sequenced, and then the results of the sequencing were analyzed for dynamic trends. Expression pattern clustering analysis was performed to demonstrate the expression of genes in the significant trend modules in each group of samples. We first chose the genes related to the trend module for WGCNA analysis, then constructed the PPI network of module genes related to propofol treatment group, and screened the key genes. Finally, GSEA analysis was performed on the key genes. Overall, 2,506 genes showed a decreasing trend with increasing propofol concentration, and 1,871 genes showed an increasing trend with increasing propofol concentration. WGCNA analysis showed that among them, turquoise panel genes were negatively correlated with propofol treatment, and genes with Cor R >0.9 in the turquoise panel were selected for PPI network construction. The MCC algorithm screened a total of five key genes (CD86, IL10RA, PTPRC, SPI1, and ITGAM). GSEA analysis showed that CD86, IL10RA, PTPRC, SPI1, and ITGAM are involved in the PRION_DISEASES pathway. Our study showed that propofol sedation can affect mRNA expression in the hippocampus, providing new ideas to identify treatment of nerve injury induced by propofol anesthesia. [ABSTRACT FROM AUTHOR]

Although research on the discrete global grid systems (DGGSs) has become an essential issue in the era of big earth data, there is still a gap between the efficiency of current encoding and operation schemes for hexagonal DGGSs and the needs of practical applications. This paper proposes a novel and efficient encoding and operation scheme of an optimized hexagonal quadtree structure (OHQS) based on aperture 4 hexagonal discrete global grid systems by translation transformation. A vector model is established to describe and calculate the aperture 4 hexagonal grid system. This paper also provides two different grid code addition algorithms based on induction and i j k coordinate transformation. We implement the transformation between OHQS codes and geographic coordinates through the i j , i j k and I J K coordinate systems. Compared with existing schemes, the scheme in this paper greatly improves the efficiency of the addition operation, neighborhood retrieval and coordinate transformation, and the coding is more concise than other aperture 4 hexagonal DGGSs. The encoding operation based on the i j k coordinate system is faster than the encoding operation based on the induction and addition table. Spatial modeling based OHQS DGGSs are also provided. A case study with rainstorms demonstrated the availability of this scheme. [ABSTRACT FROM AUTHOR]

Dissipative particle dynamics (DPD) is used to investigate solvent flow controlled by a cylindrical nanofluidic channel grafted with polymer brushes. Results for monomer and solvent beads density for different solvent quality were obtained, as well as the height and inclination angle of the polymer brushes in Poiseuille flow. The velocity profile and solvent permeability in Poiseuille flow for varying solvent quality were also examined. The polymer brushes expand and inhibit flow under good solvent conditions. However, under poor solvent conditions the chains collapse to open the channel. Additionally, the dependence of the permeability on the grafting density is given. The results indicate that the system is capable of changing the permeability and flow rate drastically upon changing the solvent quality. [ABSTRACT FROM PUBLISHER]

Drugs for the treatment of tumors could result in cardiotoxicity and cardiovascular diseases. We aimed to explore the anticancer properties of Huang yam as well as its cardioprotective properties using network pharmacology and molecular docking technology. The cardiovascular targets of the major chemical components of Huang yam were obtained from the following databases: TCMSP, ETCM, and BATMAN-TCM. The active ingredients of Huang yam were obtained from SwissADME. The cardiovascular targets of antitumor drugs were obtained using GeneCards, OMIM, DrugBank, DisGeNET, and SwissTargetPrediction databases. The drug-disease intersection genes were used to construct a drug-compound-target network using Cytoscape 3.7.1. A protein-protein interaction network was constructed using Cytoscape's BisoGenet, and the core targets of Huang yam were screened to determine their antitumor properties and identify the cardiovascular targets based on topological parameters. Potential targets were imported into the Metascape platform for GO and KEGG analysis. The results were saved and visualized using R software. The components with higher median values in the network were molecularly docked with the core targets. The network contained 10 compounds, including daucosterol, delusive, dioxin, panthogenin-B, and 124 targets, such as TP53, RPS27A, and UBC. The GO function enrichment analysis showed that there were 478 items in total. KEGG enrichment analysis showed a total of 140 main pathways associated with abnormal transcription of cancer, PI3K-Akt signaling pathway, cell cycle, cancer pathway, ubiquitination-mediated proteolysis, and other pathways. Molecular docking results showed that daucosterol, delusive, dioxin, and panthogenin-B had the highest affinity for TP53, RPS27A, and UBC. The treatment of diseases using traditional Chinese medicine encompasses multiple active ingredients, targets, and pathways. Huang yam has the potential to treat cardiotoxicity caused by antitumor drugs. [ABSTRACT FROM AUTHOR]