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At present, various public health emergencies have forced a deeper study of measures to prevent infectious diseases. To prevent the spread of infectious diseases on large cruise ships, the use of negative pressure isolation cabins is an effective method. However, existing cruise ships rarely use negative pressure isolation cabins or use them with shortcomings such as unreasonable layout of air inlets, which do not effectively reduce the risk of infection for medical staff while isolating patients. To solve this problem, first, the method of active air interference and the principle of proximity of the fresh air outlet were examined in this paper, and four groups of optimization schemes were designed. Second, by analyzing the diffusion of droplets in three breathing modes (coughing, sneezing, and talking while wearing or not wearing a mask), the direction of droplets and the efficiency of pollutant discharge under the condition of coughing were compared. Finally, in this paper, the infection risk of contact transmission and aerosol transmission was optimized by using the linear quantitative evaluation method and MSDR method, respectively. The results showed that the auxiliary air intake layout of optimal scheme 2 can effectively reduce the risk of infection for medical personnel in negative pressure isolation cabins. This study provides a useful reference for the design and optimization of negative pressure isolation cabins in future cruise ships. [ABSTRACT FROM AUTHOR]

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Gene therapy is one of the most widely studied treatments and has the potential to treat a variety of intractable diseases. The skin's limited permeability, as the body's initial protective barrier, drastically inhibits the delivery effect of gene medicine. Given the potential adverse effects and physicochemical features of the medications, improving generic drug penetration into the skin barrier and achieving an effective level of target tissues remains a challenge. Microneedles have made tremendous improvements in aided gene transfer and medication delivery as a unique method. Microneedles offer the advantage of being minimally invasive and painless, as well as the ability to distribute gene medicines straight through the stratum corneum. Microneedles have been used to penetrate skin tissue with various nucleic acids and medicines in recent years, allowing for a wide range of applications in the treatment of skin ailments. This review focuses on skin-related disorders and immunity, and it primarily discusses the progress of microneedle transdermal gene therapy in recent years. It also complements the current major vectors and related microneedle gene therapy applications. [ABSTRACT FROM AUTHOR]

Background: Promising cancer chemotherapy requires the development of suitable drug delivery systems (DDSs). Previous research has indicated that a hydrogel is a powerful DDS for tumor therapy and holds great potential to offer a feasible method for cancer management. Methods: In this study, glutathione-gellan gum conjugate (GSH-GG) was synthesized through chemical reaction. Doxorubicin hydrochloride (DOX) was loaded into GSH-GG to accomplish DOX-loaded GSH-GG. The properties, injectability, drug release, and in vitro and in vivo anticancer effects of DOX-loaded GSH-GG were tested. Results: DOX-loaded GSH-GG showed a temperature-ion dual responsive gelling property with good viscosity, strength, and injectability at an optimized gel concentration of 1.5%. In addition, lower drug release was found under acidic conditions, offering beneficial long-acting drug release in the tumor microenvironment. DOX-loaded GSH-GG presented selective action by exerting substantially higher cytotoxicity on cancer cells (4T1) than on normal epithelial cells (L929), signifying the potential of complete inhibition of tumor progression, without affecting the health quality of the subjects. Conclusions: GSH-GG can be applied as a responsive gelling material for delivering DOX for promising cancer therapy. [ABSTRACT FROM AUTHOR]

As a pathogenic worldwide pathogen, Staphylococcus aureus (S. aureus) has brought great challenges to the prevention and treatment of diseases in the community. Although antimicrobial peptides show potent antibacterial activity because of their unique bactericidal mechanism, their inherent cationic toxicity cannot be ignored. Utilizing the related characteristics of S. aureus to achieve targeted therapy can reduce the toxicity to host cells to a great extent. Herein, we designed Cy7-labeled antimicrobial peptide (GLFVDK-(-Cy7)-GKRWWKWWRRGPLGVRGC) with S. aureus targeting recognition peptide (GLFVD) and gelatinase cleavage site (PLGVR), which together with SH-PEG was anchored to gold nanostars (AuNS) by the Au–thiol bond to form a photothermal nanoprobe (APA) targeting S. aureus. The size of the generated APA nanoprobe was 201 ± 3.7 nm, and it was nonfluorescent in the physiological environment due to the fluorescence resonance energy transfer between the AuNS core and Cy7. In vitro results showed that in the gelatinase environment secreted by S. aureus , antimicrobial peptides were released from AuNS and restored the fluorescence of Cy7 in situ, targeting and priority killing of S. aureus. In the mouse wound model of double bacterial infection, APA effectively removed S. aureus from the infected site and promoted the rapid healing of infected wounds through gelatinase-responsive drug release and photothermal synergistic antibacterial treatment. [ABSTRACT FROM AUTHOR]

As a highly absorbent and hydrophobic material with a three-dimensional network structure, hydrogels are widely used in biomedical fields for their excellent biocompatibility, low immunogenicity, adjustable physicochemical properties, ability to encapsulate a variety of drugs, controllability, and degradability. Hydrogels can be used not only for wound dressings and tissue repair, but also as drug carriers for the treatment of tumors. As multifunctional hydrogels are the focus for many researchers, this review focuses on hydrogels for antitumor therapy, hydrogels for antibacterial therapy, and hydrogels for co-use in tumor therapy and bacterial infection. We highlighted the advantages and representative applications of hydrogels in these fields and also outlined the shortages and future orientations of this useful tool, which might give inspirations for future studies. [ABSTRACT FROM AUTHOR]

Medical cabins within negative-pressure ambulances currently only use the front air supply, which causes poor emission of infectious disease droplets. For this problem, based on the classification and design methods of airflow organization, the side and top supply airflow organization model has been designed to study the influence of these airflow organization models on the spread of droplet particles. The distribution of droplet particles within airflow organization models, under conditions in which the patient is coughing and sneezing, is analyzed. According to the comparison and analysis of this distribution, the state of droplet particles, the emission efficiency, and the security coefficient are studied. The response surface method is used to optimize the emission efficiency and security coefficient of the airflow organization. According to the characteristics of the medical cabin within negative-pressure ambulances, a dose-response model is used to evaluate the infection risk of medical personnel and then the infection probability is obtained. These research results can be used to improve the ability of negative-pressure ambulances to prevent cross-infection. [ABSTRACT FROM AUTHOR]

In this study, the superhydrophobic composite coatings for self-cleaning were fabricated by mixing fluorine resin and two kinds of nanoparticles of carbon nanotubes (CNTs) and SiO2. When the mass ratio of CNTs to SiO2 is 2:3 and the added amount of nanoparticles is 75 wt. %, the superhydrophobic composite coatings with a water contact angle of 156.8° show the best self-cleaning property and 3.6° of contact angle hysteresis. Furthermore, the superhydrophobic composite coatings demonstrate good properties such as chemical resistance, thermal stability, and mechanical stability. The superhydrophobic composite coatings could be used for oil/water separation and could be applied to various substrate surfaces such as glass plates, cloth, board, steel plate, PVC plate, and so on. The superhydrophobic composite coatings show practical value in many fields because of their low cost and large area preparation. [ABSTRACT FROM AUTHOR]

Dual intramolecular FRET polymers are synthesized via Suzuki coupling and their luminescence characteristics from aggregation‐caused quenching (ACQ) to aggregation‐induced emission (AIE) is modulated conveniently by adjusting the charged ratios. The finally obtained AIE polymer is further employed to construct doxorubicin loaded nanoparticles as a promising theranostics platform for cancer therapy. [ABSTRACT FROM AUTHOR]

Bifunctional magnetic/fluorescent core-shell silica nanospheres (MNPs) encapsulated with the magnetic Fe3O4 core and a derivate of 8-amimoquinoline (N-(quinolin-8-yl)-2-(3-(triethoxysilyl) propylamino) acetamide) (QTEPA) into the shell were synthesized. These functional MNPs were prepared with a modified stöber method and the formed Fe3O4@SiO2-QTEPA core-shell nanocomposites are biocompatible, water-dispersible, and stable. These prepared nanoparticles were characterized by X-ray power diffraction (XRD), transmission electron microscopy (TEM), thermoelectric plasma Quad II inductively coupled plasma mass spectrometry (ICP-MS), superconducting quantum interference device (SQUID), TG/DTA thermal analyzer (TGA) and Fourier transform infrared spectroscopy (FTIR). Further application of the nanoparticles in detecting Zn2+ was confirmed by the fluorescence experiment: the nanosensor shows high selectivity and sensitivity to Zn2+ with a 22-fold fluorescence emission enhancement in the presence of 10 μM Zn2+. Moreover, the transverse relaxivity measurements show that the core-shell MNPs have T2 relaxivity (r2) of 155.05 mM−1 S−1 based on Fe concentration on the 3.0 T scanner, suggesting that the compound can be used as a negative contrast agent for MRI. Further in vivo experiments showed that these MNPs could be used as MRI contrast agent. Therefore, the new nanosensor provides the dual modality of magnetic resonance imaging and optical imaging. [ABSTRACT FROM AUTHOR]

Based on the theory of porous electrodes and the properties of lithium iron batteries, an electrochemical‐thermal coupling model of a single cell was established. The model was mainly used to study the temperature rise and temperature distribution characteristics in different regions of lithium iron batteries under different working conditions. In addition, a heat dissipation comparison analysis was carried out for different types of liquid cold runners, the optimal runner scheme was selected, and a structural optimization analysis was carried out. The simulation results show that the lithium iron battery discharges under the same ambient temperature and different C rates, and the battery temperature continuously increases with C. The temperature rise is mainly affected by Joule heat, and when the lithium iron battery is discharged at the same C but different ambient temperatures, the temperature rise of the lithium iron battery shows a decreasing trend with the increase in ambient temperature in a certain temperature range. The serial flow channel solution induces the best thermal behavior. Using the response surface optimization analysis, the three independent variable factors at which the temperature equilibrium R reaches the largest value under the liquid cooling module model are the rectangular flow channel length‐to‐width ratio, flow rate, and thermal conductivity. [ABSTRACT FROM AUTHOR]

DNA possesses various chemical and physical properties which make it important in biological analysis. The opportunity for DNA to 'meet' capillary-based microsystems is rapidly increasing owing to the expanding development of miniaturization. Novel capillary-based methods can provide favourable platforms for DNA–ligand interaction assay, DNA translocation study, DNA separation, DNA aptamer selection, DNA amplification assay, and DNA digestion. Meanwhile, DNA exhibits great potential in the fabrication of new capillary-based biosensors and enzymatic bioreactors. Moreover, DNA has received significant research interest in improving capillary electrophoresis (CE) performance. We focus on highlighting the advantages of combining DNA and capillary-based microsystems. The general trend presented in this review suggests that the 'meeting' has offered a stepping stone for the application of DNA and capillary-based microsystems in the field of analytical chemistry. [ABSTRACT FROM AUTHOR]

Byline: Shuwen Zhou, William Lawrance, Siqi Zhang Automatic concrete pouring is essential to lessen the operator's labour intensity and increase productivity. The concept of automatic pouring and semi-automatic pouring are introduced to the boom control system. The concrete pouring process and the kinematics of the boom sections were analysed, including the inverse kinematics problem. An interpolation method was applied to obtain the boom's pose according to the position of the end hose. Four linear displacement sensors were used to measure angular displacements, which simplified the configuration of the control system. When doing automatic pouring, the control system can automatically pour a long narrow field while the semi-automatic pouring system can keep the end hose moving horizontally on a large platform. A 3D simulation was programmed to simulate the process of automatic pouring and verify the control algorithm. The simulation result shows that the system can pour concrete on a long narrow field automatically and the booms movement is smooth.

In order to meet the filtration separation of hazardous materials on hazardous materials collection truck, the most popular separation devices, such as the cyclone separator and the filter cartridge, are combined to form a new filtration device in this study. The advantages of the two devices are utilized to achieve effective separation of solid particles and prevent secondary pollution. Among the various structural influence factors of filtration equipment, four structural parameters that affect the separation performance significantly are selected as optimization variables. The response surface methodology was used to design the simulation experiment. Using fluid mechanics analysis software, multiple sets of parameters were simulated. Then, the simulation data was used to establish a mathematical model of separation efficiency, and structural optimization analysis was performed based on the mathematical model. Finally, the results show that the inner exhaust pipe diameter and the cone height have more influence on the efficiency of the cyclone separation structure. The interaction between the diameter and insertion depth of the inner exhaust pipe is also obvious. Among the four optimization variables, there is an optimum value for the inner exhaust pipe insertion depth, and the effect of the other three factors on the separation efficiency is monotonic. In the case of a total separation efficiency of 99.9% and after optimizing the combined model within a reasonable interval, 81.25% of the 1-μm particles can be removed by the cyclone separation part, and only 18.75% are removed by the filter cartridge. [ABSTRACT FROM AUTHOR]

In view of the problem of inaccurate scheduling by using traditional resource scheduling method, because the method is mainly based on extracting and classifying the resource features to make scheduling, ignoring the effect of the feature relevance between the resources on the scheduling results. This paper presents a model for multimedia cloud resource scheduling based on multi- device constraint. In this method the objective function is no longer constrained only by the CPU computing capacity and the minimized completion time, but to achieve a minimum time-consuming of CPU, memory and other peripherals operation are considered as the scheduling objectives. Then the utilization of solving constrained jointly is employed to obtain the mapping relationship of the optimal virtual and physical machine. Moreover, a regressive dimensionality reduction algorithm is designed for this scheduling model to solve the high dimensional problems aroused by multi-device constraints. Simulation results show that the improved algorithm has a better performance than the traditional algorithm, has a good efficiency and has a certain convergence. [ABSTRACT FROM AUTHOR]

Although the conductive stretchable woven fabric has been widely used as the sensitive material of strain sensors monitoring human motion, it is lack of a deep understanding of the determinants of its electrical resistance change under uniaxial tensile strain. This study chose two kinds of typical stretchable plain woven fabric, i.e. cotton/spandex core-spun yarn fabric and polyester/spandex filament yarn fabric, and they were coated by in situ polymerization of polypyrrole. Their electromechanical responses under certain uniaxial tensile loadings were measured and compared. Meanwhile, by a multi-architecture analysis, i.e. the intrinsic resistance of yarns, the contact resistance of interlacing yarns and the contact resistance of adjacent yarns in parallel, several hypotheses were proposed and tested to determine the determinants of electrical resistance change under tensile strains. The results showed that the resistance change in woven fabric with in situ polymerization of polypyrrole mainly depends on the contact resistance of the adjacent conductive yarns in tensile direction, and the electromechanical responses of the cotton/spandex core spun yarn are significantly different from those of the polyester/spandex filament yarn. It was concluded that the conductive yarn density and fabric structure are critical parameters of woven fabric as resistive strain sensor. [ABSTRACT FROM AUTHOR]

The ambient temperature has a great influence on the discharge and charging performance of a lithium battery, which may cause thermal runaway of the battery pack in extreme cases. In terms of the poor cooling effect caused by only using the cooling bottom plate for liquid cooling and the fact that the battery pack needs to be preheated before it can be used normally, a new cooling structure design was carried out, and a variety of cooling schemes and preheating schemes were proposed for analysis and comparison. The Star ccm+ simulation software was used to analyze and study their liquid cooling performance and preheating performance under different conditions. The best cooling scheme and preheating scheme were obtained by comparing the results of the simulation analysis. The simulation results show that the cooling performance of the cooling scheme using two vertical cooling plates and one cooling bottom plate is the best, and the preheating performance is best when the preheating liquid is used with a certain temperature flow through the preheating pipe of the battery pack for a period of time, and then the battery pack is discharged until the battery pack temperature reaches the working temperature range. The research results have reference value for the control of the ambient temperature of a vehicle lithium iron phosphate battery. [ABSTRACT FROM AUTHOR]

Infection-induced chronic wounds cause prolonged pains, a high risk of amputation, and even increased mortality in immunocompromised patients. Here we report an antibacterial microneedle (MN) patch, which features high degradability in biological fluids and gelatinase-responsive release of an antibacterial photothermal peptide AMP-Cypate. We first synthesize gelatin nanoparticles (GNPs) and then conjugate the AMP-Cypate to afford composite AMP-Cypate@GNPs. The proteinaceous nanoparticles can responsively release AMP-Cypate in the presence of gelatinase, an enzyme secreted specifically by Staphylococcus aureus (S. aureus). AMP-Cypate@GNPs were then deposited in the tips of MNs fabricated by PVP and recombinant human type III collagen (Col III) to devise the antibacterial MN/AMP-Cypate@GNP patches. When applied to the infection site, MNs break through the epidermis and the stratum corneum, dissolve in the infected dermis, reach the bacterial colony or biofilm, release AMP-Cypate@GNPs, and exert a gelatinase-responsive photothermal therapy under near-infrared (NIR) irradiation to kill the pathogen S. aureus. In a rat model of staphylococcal infection-induced chronic wounds mimicking the condition of diabetic foot ulcer, the antibacterial MN/AMP-Cypate@GNP patches eradiated the bacterial infection and resulted in complete healing of the wounds, proving its potential application in the treatment of chronic wound infections and diabetic foot ulcers. [Display omitted] [ABSTRACT FROM AUTHOR]