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The wide application of big data not only provides convenience for the teaching between teachers and students, but also plays a great role in the education and training of college students. However, how to cultivate students' ability to learn English independently in the current era remains to be studied. Under the background of big data, it is very important for today's education to make effective use of this technological advantage to explore scientific and reasonable strategies, stimulate college students' attention to English autonomous learning, and explore the learning process. Investigating the value of specific big data technology is also an important consideration in this study. At the same time, graduate students who are not English majors usually have fewer English courses, and students' English level is also very different. Therefore, we should also pay attention to improving students' oral English ability and pay special attention to the cultivation of students' self-discipline and autonomous learning ability.

Surfactant protein B (SP-B) deficiency is a rare genetic disease that causes fatal respiratory failure within the first year of life. Currently, the only corrective treatment is lung transplantation. Here, we co-transduced the murine lung with adeno-associated virus 6.2FF (AAV6.2FF) vectors encoding a SaCas9-guide RNA nuclease or donor template to mediate insertion of promoterless reporter genes or the (murine) Sftpb gene in frame with the endogenous surfactant protein C (SP-C) gene, without disrupting SP-C expression. Intranasal administration of 3 × 1011vg donor template and 1 × 1011vg nuclease consistently edited approximately 6% of lung epithelial cells. Frequency of gene insertion increased in a dose-dependent manner, reaching 20%–25% editing efficiency with the highest donor template and nuclease doses tested. We next evaluated whether this promoterless gene editing platform could extend survival in the conditional SP-B knockout mouse model. Administration of 1 × 1012vg SP-B-donor template and 5 × 1011vg nuclease significantly extended median survival (p = 0.0034) from 5 days in the untreated off doxycycline group to 16 days in the donor AAV and nuclease group, with one gene-edited mouse living 243 days off doxycycline. This AAV6.2FF-based gene editing platform has the potential to correct SP-B deficiency, as well as other disorders of alveolar type II cells.

Nowadays, infectious diseases persist as a global crisis by causing significant destruction to public health and the economic stability of countries worldwide. Especially bacterial infections remain a most severe concern due to the prevalence and emergence of multi-drug resistance (MDR) and limitations with existing therapeutic options. Antibacterial photodynamic therapy (APDT) is a potential therapeutic modality that involves the systematic administration of photosensitizers (PSs), light, and molecular oxygen (O2) for coping with bacterial infections. Although the existing porphyrin and non-porphyrin PSs were effective in APDT, the poor solubility, limited efficacy against Gram-negative bacteria, and non-specific distribution hinder their clinical applications. Accordingly, to promote the efficiency of conventional PSs, various polymer-driven modification and functionalization strategies have been adopted to engineer multifunctional hybrid phototherapeutics. This review assesses recent advancements and state-of-the-art research in polymer-PSs hybrid materials developed for APDT applications. Further, the key research findings of the following aspects are considered in-depth with constructive discussions: i) PSs-integrated/functionalized polymeric composites through various molecular interactions; ii) PSs-deposited coatings on different substrates and devices to eliminate healthcare-associated infections; and iii) PSs-embedded films, scaffolds, and hydrogels for regenerative medicine applications.

The aim of this work is to study the influence of chamfered perforation and chamfering on the heave and pitch motion of a single floating wind power platform with an anti-heave device. Firstly, the hydrodynamic performance of a single floating body with different chamfers, or without perforation, is calculated and analysed. Secondly, the motion of a model without perforation and with 35° chamfered perforation is captured and studied in a towing tank. The results show that when the wave height is large and the period is small, the perforated device has a certain effect. When the wave height and period are small, the pitch suppression effect of chamfered perforation is more obvious than that of non-chamfered perforation. When the period and wave height are large, the heave suppression effect of non-chamfered perforation is better than that of chamfered perforation. In experimental research, the perforated floating body has a certain effect on restraining the heave and pitch of a floating body under most working conditions, and the effect of restraining the pitch is obviously better than that of restraining the heave.

•Microgravity disrupts the balance of bone remodeling.•MiR-138-5p was a mechanosensitive miRNA and inhibited osteoblast proliferation and induced apoptosis under simulated microgravity.•SIRT1 was downregulated and negatively correlated with the expression of miR-138-5p under simulated microgravity.•MiR-138-5p inhibited osteoblast proliferation and promoted osteoblast apoptosis by targeting SIRT1.

Functional microdevices based on responsive hydrogel show great promise in targeted delivery and biomedical analysis. Among state-of-the-art techniques for manufacturing hydrogel-based microarchitectures, femtosecond laser two-photon polymerization distinguishes itself by high designability and precision, but the point-by-point writing scheme requires mechanical apparatuses to support focus scanning. In this work, by predesigning holograms combined with lens phase modulation, multiple femtosecond laser spots are holographically generated and shifted for prototyping of three-dimensional shape-morphing structures without any moving equipment in the construction process. The microcage array is rapidly fabricated for high-performance target capturing enabled by switching environmental pH. Moreover, the built scaffolds can serve as arrayed analytical platforms for observing cell behaviors in normal or changeable living spaces or revealing the anticancer effects of loaded drugs. The proposed approach opens a new path for facile and flexible manufacturing of hydrogel-based functional microstructures with great versatility in micro-object manipulation.

Some high rockfill dams, built on deep overburden, utilize double concrete cutoff walls for seepage control, thereby introducing increased complexity to seepage characteristics in the dam foundation. This study focuses on a core rockfill dam located on the Dadu River in China, investigating the impact of dam body and foundation permeability coefficients on the percentages of hydraulic head reduction by the double cutoff walls. A multifactor sensitivity analysis, based on finite element method, is conducted to analyze this influence. Subsequently, an inversion model, integrating support vector regression and whale optimization algorithm, is proposed to identify parameters that align with seepage monitoring data. Results indicate that the permeability coefficients of the surface bedrock and the main grouting curtain exert the most significant influence. Parameters derived from the inversion model yield finite element calculations consistent with monitoring data. Moreover, upstream water level minimally affects the distribution of hydraulic head reduction percentages by the double cutoff walls. And the seepage gradient (G) in the dam foundation overburden remains below the permissible limit, with its relationship to the upstream water level (L) fitted as G=-1.03318+6.96E-4×L.This study may offer valuable insights for the construction and operational management of similar projects employing double cutoff walls.

The emergence of antibiotic drug resistance has undermined the efficacy of antibiotics, and is becoming a severe threat to public health. To combat antibiotic drug resistance and to replace traditional antibiotic treatment, an alternative strategy based on antibacterial photodynamic therapy (APDT), which has broad applicability, high efficiency and less potential of developing antibiotic drug resistance, has been developed. In this work, the cationic porphyrin-based nanoparticles (NPs) were prepared by epoxy–amine chain extension polymerization of diepoxy-terminated poly(ethylene glycol) (PEG) and tetraamino-containing porphyrin, followed by quaternization with methyl iodine and butyl bromide. The as-obtained cationic porphyrin NPs preserved the photophysical properties of porphyrin derivatives, and can efficiently generate singlet oxygen (1O2) under 635 nm laser irradiation. The cationic porphyrin-based NPs displayed intrinsic antibacterial properties, and exhibited strong APDT effect on Gram-positive bacteria by destroying the bacterial cell membranes. Upon incubation with different bacterial strains, it was found that they could be utilized to identify Gram-positive bacteria by observing the sedimentation behavior of their mixtures, and visualizing their co-cultured and centrifugal bacteria cakes. In addition, the cationic porphyrin-based NPs had good hemocompatibility and low dark cytotoxicity.

In this Letter, a magnetically driven rotary microfilter that enables switching the modes of filtering and passing is fabricated in microfluidic devices via two-photon polymerization using a femtosecond laser for selective filtering of particles. The high-quality integration of a microfilter is ensured by accurately formulating the magnetic photoresist and optimizing the processing parameters. By changing the direction of the external magnetic field, the fabricated microfilter can be remotely manipulated to rotate by desired angles, thereby achieving the “filtering” or “passing” mode on demand. Taking advantage of this property, the magnetically rotary microfilter realizes multi-mode filtering functions such as capturing 8 µm particles/passing the 2.5 µm particles and passing both particles. More importantly, the responsive characteristic increases the reusability of the microchip. The lab-on-chip devices integrated with remotely rotary microfilters by the femtosecond laser two-photon polymerization with the functional photoresist will offer extensive applications in chemical and biological studies.

The marked increase in bacterial colonization of medical devices and multiple drug resistance to traditional antibiotics underline the pressing need for developing novel antibacterial surface coatings. In the present investigation, natural polyphenol tannic acid (TA)-capped silver nanoparticles (TA–Ag NPs) were synthesized via an environmentally friendly and sustainable one-step redox reaction under UV irradiation with a simultaneous and uniform deposition on polydimethylsiloxane (PDMS) and other substrate surfaces. In the synthesis process, the dihydroxyphenyl and trihydroxyphenyl groups of TA actively participate in Ag+reduction, forming co-ordination linkages with Ag NPs and bestowing the deposition on the PDMS surface. The physico-chemical features of TA–Ag NPs were characterized in detail. Microscopic examination, surface elemental analysis, and wettability measurements clearly reveal the decoration of TA–Ag NPs on the substrate surfaces. The modified PDMS surfaces can kill the adhered bacteria or resist the bacterial adhesion, and no live bacteria can be found on their surfaces. Most importantly, the modified PDMS surfaces exhibit predominant antibacterial effects both in vitro in the catheter bridge model and in vivo in a rat subcutaneous infection model. On the other hand, the functionalized surfaces exhibit only a negligible level of cytotoxicity against L929 mouse fibroblasts with no side effects on the major organs of Sprague–Dawley rats after implantation, indicating their biocompatibility for potential biomedical applications.

Medical device‐associated infections (MDAI) caused by planktonic pathogens are of serious concern worldwide due to the emergence of drug resistance resulting from continuous overuse or misuse of antibiotics. Therefore, the design of non‐antibiotics‐based treatment for MDAI is of crucial importance. Black phosphorus (BP), a novel 2D material, has recently received much attention owing to its remarkable physical, chemical, mechanical, and functional features. However, the intricacy of the fabrication process has severely hampered the development of BP in prospective applications. In this study, a simple and eco‐friendly liquid‐phase exfoliation method of phytic acid (PA)‐promoted exfoliation of BP nanosheets (PA@BP NSs) is developed for their potential application in antibacterial photothermal therapy. To impart the antimicrobial effects, the polydimethylsiloxane surfaces are functionalized with quaternized polymer (polyquaternium‐2 or PQ) and PA@BP NSs, leading to the formation of PA‐BP‐PQ composite coatings. In addition to the contact‐killing antibacterial effect of the cationic PQ, the PA‐BP‐PQ coating exhibits remarkable near‐infrared irradiation‐triggered bactericidal effects with low cytotoxicity both in vitro and in vivo. This study proposes a simple liquid‐phase exfoliation technique for the fabrication of BP NSs and a one‐step approach for the construction of PA‐BP‐PQ composite coatings for bi‐modal (contact‐killing and photothermal) antimicrobial therapy. A simple and eco‐friendly method of phytic acid‐promoted exfoliation of black phosphorus nanosheets (PA@BP NSs) is developed. The resultant PA@BP NSs are conjugated with cationic polyquaternium‐2 (PQ), leading to the formation of PA‐BP‐PQ composite coatings on the polydimethylsiloxane surface. The PA‐BP‐PQ composite coating exhibits remarkable bi‐modal (contact‐killing and photothermal) antimicrobial therapy with good biocompatibility both in vitro and in vivo.

The emerging two-photon polymerization (TPP) technique enables high-resolution printing of complex 3D structures, revolutionizing micro/nano additive manufacturing. Various fast scanning and parallel processing strategies have been proposed to promote its efficiency. However, obtaining large numbers of uniform focal spots for parallel high-speed scanning remains challenging, which hampers the realization of higher throughput. We report a TPP printing platform that combines galvanometric mirrors and liquid crystal on silicon spatial light modulator (LCoS-SLM). By setting the target light field at LCoS-SLM’s diffraction center, sufficient energy is acquired to support simultaneous polymerization of over 400 foci. With fast scanning, the maximum printing speed achieves 1.49 × 108voxels s–1, surpassing the existing scanning-based TPP methods while maintaining high printing resolution and flexibility. To demonstrate the processing capability, functional 3D microstructure arrays are rapidly fabricated and applied in micro-optics and micro-object manipulation. Our method may expand the prospects of TPP in large-scale micro/nanomanufacturing.

Decomposition of concrete calcium compounds in the leaching process constantly changed the concrete gravity dam’s sliding and resisting forces, which endangered project safety. Nonetheless, the calcium leaching effect on dam sliding stability has not been studied previously, and the dam factor of safety(FOS) evolution remained unknown. This research numerically investigated the impact of calcium leaching on concrete gravity dam stability. A relation between bonded cohesion of concrete-rock interface and CaO/SiO2ratio of CSH is presented to investigate the shear strength deterioration in the leaching process. The evolution of dam FOS, sliding and resisting forces in a hundred years is obtained. The results showed that the calcium leaching reduced dam stability. Parameter sensitivity analysis showed that the grout curtain hydraulic conductivity and rock foundation type significantly affect the dam FOS. We can improve dam stability in the leaching process by reducing the initial hydraulic conductivity of the grout curtain.

Abstract: Recent studies have determined that gene expression profiling using microarray technology can be used to identify tumor-related molecules. The objective of this study was to screen the differentially expressed genes between pleomorphic adenoma (PA) and the normal tissue adjacent to PA using cDNA microarrays and to further validate the differentially expressed genes by real-time PCR. In this study, we selected five pairs of PA and the surrounding normal salivary gland tissues. The total RNA was isolated from tumor and normal tissues and purified to mRNA. The mRNA was reverse-transcribed to cDNA with the incorporation of fluorescent-labeled dUTP to prepare the hybridization probes. The mixed probes were hybridized to Whole Human Gene Expression Microarrays by Agilent. Tumor-related genes were screened by analyzing the fluorescence intensity. As a result, a total of 447 genes were found to be differentially expressed between PA and normal tissue adjacent to PA. Among them, 185 genes were up-regulated and 262 genes were down-regulated in PA. By constructing a network from the differentially expressed genes, some genes, such as Gli2 and CTNNB1, were identified as being at the core of the network. In addition, differential gene expression was validated for 2 up-regulated genes, Gli2 and LOX, using real-time PCR and the results were consistent with those of the cDNA microarray analysis thus verifying the credibility of the microarray data. Therefore, our microarray data may provide clues for finding novel genes involved in the development of PA, and shed light on finding new targets for diagnosis and therapy of PA. Further characterization of these differentially expressed genes will be useful in understanding the genetic basis for PA.

Millirobots that can be actuated and accurately steered by external magnetic fields, are highly desirable for bioengineering and wearable devices. However, existing designs of millirobots are limited by their specific material composition, hindering their wider application due to a lack of scalability. Here, we present a method for the generation of heterogeneous magnetic millirobots based on magnetic coatings. The coatings, composed of hard-magnetic CrO2particles dispersed in an adhesive solution, impart magnetic actuation to diverse substrates with planar sheets or 3D structures. Millirobots constructed from the coatings can be readily reprogrammed with intricate magnetization profiles using laser localized heating, enabling reconfigurable shape changes under magnetic actuation. Using this approach, we demonstrate on-demand maneuvering capability of reconfiguring locomotion involving crawling, overturning and rolling with a single millirobot. Various functions, including the ability to catch a fast-moving ball, object transportation, and targeted assembly, have been achieved. This adhesive strategy facilitates the design of millirobots and may open avenues to the creation of complex millirobots for broad applications.

The dispersion and coupling characteristics of the coupled image guides are studied by using the odd-even mode principle and effective dielectric constant method. The practical design of the image guide directional couplers is presented. The experiments of 3-dB and 10-dB couplers in ka band show several good features which are very useful to millimeter wave integrated circuits with flat coupling, easy design and fabrication, mechanical stability and low losses.

A practical design of nonradiative dielectric (NRD) waveguide directional couplers is presented. The dispersion characteristics of coupled NRD-guides and the scattering coefficients of NRD-guide directional couplers are studied as well as the transitions from metal rectangular wave-guide to NRD-guide couplers. Experiments of 3-dB and 10-dB NRD-guide couplers in ka-band show that the couplers are of good performance and promise in millimeter-wave integrated circuits.

The on-demand manipulation of gas bubbles in aqueous ambient environments is fundamental to many fields such as microfluidics and biochemical microanalysis. However, most bubble manipulation strategies are limited to restricted locomotion on the confined surfaces without spatial convenience of transport. Herein, we report a kind of biomimetic bubble manipulator with mechanoswitchable interfaces (MSIs), featuring the advantages of parallel bubble control and spatial maneuvering flexibility. By the synergic action between Janus aluminum membrane and superaerophilic microfiber array, the gas–MSI interfacial adhesion can be reversibly switched to achieve capturing/releasing underwater bubbles. Moreover, the adhesion force of MSI can be readily tuned by diverse experimental parameters including surface roughness, fiber number, diameter, and spacing of the neighboring microfibers, which are further systematically investigated. Relying on this mobile platform, we demonstrate a series of powerful applications including bubble parallel control, bubble array regrouping, arbitrary bubble transport and even manipulating underwater solids through bubbles, which are otherwise challenging for conventional approaches. We envision that this versatile platform will bring new insights into potential applications, such as cross-species sample control and handheld gas microsyringe.

Worldwide increasing emergence of carbapenem-resistant Acinetobacterspp. has rendered the limited availability of effective antimicrobial agents and has become a major public health concern. In this study, we report the draft genome sequence of A. pittiiTCM156, a multidrug-resistant isolate that harbored the blaOXA-357gene. The genome sequence was further analyzed by various bioinformatics methods. The genome size was estimated to be 3,807,313bp with 3508 predicted coding regions and G+C content is 38.7%. These findings have raised awareness of the possible emergence of OXA-type enzyme-producing A. pittiiisolate in China.

The increasing emergence of carbapenem-resistant Acinetobacterspp. worldwide has resulted in the limited availability of effective antimicrobial agents and has become a major public health concern. In this study, the draft genome sequence of Acinetobacter pittiiTCM292 belonging to sequence type 207 (ST207), a multidrug-resistant (MDR) isolate harbouring the New Delhi metallo-β-lactamase blaNDM-1gene, was determined using an Illumina HiSeq™ 2000 platform. The genome sequence was analysed by bioinformatics methods. The A. pittiiTCM292 genome size was estimated to be 3791758bp with 3486 predicted coding regions. These data might facilitate further understanding of the specific genomic features of MDR A. pittiiin China.

Acinetobacter baumanniihas emerged worldwide as an important opportunistic nosocomial pathogen and has become a major public health concern. In this study, the draft genome sequence of A. baumanniiTCM331 (ST208/CC92), a multidrug-resistant (MDR) isolate harbouring the blaOXA-23gene isolated in China, was determined. The genome of TCM331 was sequenced via Illumina HiSeq™ 2000, and bioinformatics analysis was performed. Important antimicrobial resistance determinants were observed in an estimated genome size of 4,058,691bp with 3838 predicted coding regions. In conclusion, these data might facilitate further understanding of the specific genomic features of MDR A. baumanniiin China.

Death domain–dependent signaling in the basal chordate amphioxus suggests that extrinsic apoptotic signaling is not restricted to vertebrates.