2D layered materials have sparked great interest from the perspective of basic physics and applied science in the past few years. Extraordinarily, many novel stacked structures that bring versatile ...properties and applications can be artificially assembled, as exemplified by vertical van der Waals (vdW) heterostructures, twisted multilayer 2D materials, hybrid dimensional structures, etc. Compared with the ordinary synthesis process, the stacking technique is a powerful strategy to achieve high‐quality and freely controlled 2D material stacked structures with atomic accuracy. This review highlights the most advanced stacking techniques involving the preparation, transfer, and stacking of high‐quality single crystal 2D materials. Apart from the 2D–2D stacked structures, 2D–0D, 2D–1D, and 2D–3D structures offer a prospective platform for the increasing application of 2D materials. The assembly strategy and physical properties of these stacked structures strongly depend on the factors in the stacking process, including the surface quality, angle control, and sample size. In addition, comparative analysis tables on the techniques involved are also available. The summary of these strategies and techniques will hopefully provide a valuable reference for relevant work.
2D stacked structures are being rapidly developed. However, the assembly and integration techniques of 2D material‐based devices are still subject to many restrictions, seriously hindering the design and development of new functional devices. As one of the most important aspects, 2D material stacking techniques are systematically summarized and analyzed in this review.
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Despite its clinical promise, photodynamic therapy (PDT) suffers from a key drawback associated with its oxygen‐dependent nature, which limits its effective use against hypoxic tumors. Moreover, both ...PDT‐mediated oxygen consumption and microvascular damage further increase tumor hypoxia and, thus, impede therapeutic outcomes. In recent years, numerous investigations have focused on strategies for overcoming this drawback of PDT. These efforts, which are summarized in this review, have produced many innovative methods to avoid the limits of PDT associated with hypoxia.
PDT beats hypoxia: Novel and robust strategies, which can improve the therapeutic efficacy of photodynamic therapy (PDT) for hypoxic tumors, have been widely investigated in recent years. These efforts have led to the development of new approaches that have changed the paradigm of PDT and provided solutions to some key problems.
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Summary Background The mcr-1 gene confers transferable colistin resistance. mcr-1 -positive Enterobacteriaceae (MCRPE) have attracted substantial medical, media, and political attention; however, so ...far studies have not addressed their clinical impact. Herein, we report the prevalence of MCRPE in human infections and carriage, clinical associations of mcr-1 -positive Escherichia coli (MCRPEC) infection, and risk factors for MCRPEC carriage. Methods We undertook this study at two hospitals in Zhejiang and Guangdong, China. We did a retrospective cross-sectional assessment of prevalence of MCRPE infection from isolates of Gram-negative bacteria collected at the hospitals from 2007 to 2015 (prevalence study). We did a retrospective case-control study of risk factors for infection and mortality after infection, using all MCRPEC from infection isolates and a random sample of mcr-1 -negative E coli infections from the retrospective collection between 2012 and 2015 (infection study). We also did a prospective case-control study to assess risk factors for carriage of MCRPEC in rectal swabs from inpatients with MCRPEC and mcr-1 negative at the hospitals and collected between May and December, 2015, compared with mcr-1 -negative isolates from rectal swabs of inpatients (colonisation study). Strains were analysed for antibiotic resistance, plasmid typing, and transfer analysis, and strain relatedness. Findings We identified 21 621 non-duplicate isolates of Enterobacteriaceae, Acinetobacter spp, and Pseudomonas aeruginosa from 18 698 inpatients and 2923 healthy volunteers. Of 17 498 isolates associated with infection, mcr-1 was detected in 76 (1%) of 5332 E coli isolates, 13 (<1%) of 348 Klebsiella pneumoniae , one (<1%) of 890 Enterobacter cloacae , and one (1%) of 162 Enterobacter aerogenes . For the infection study, we included 76 mcr-1 -positive clinical E coli isolates and 508 mcr-1 -negative isolates. Overall, MCRPEC infection was associated with male sex (209 41% vs 47 63%, adjusted p=0·011), immunosuppression (30 6% vs 11 15%, adjusted p=0·011), and antibiotic use, particularly carbapenems (45 9% vs 18 24%, adjusted p=0·002) and fluoroquinolones (95 19% vs 23 30%, adjusted p=0·017), before hospital admission. For the colonisation study, we screened 2923 rectal swabs from healthy volunteers, of which 19 were MCRPEC, and 1200 rectal swabs from patients, of which 35 were MCRPEC. Antibiotic use before hospital admission (p<0·0001) was associated with MCRPEC carriage in 35 patients compared with 378 patients with mcr-1-negative E coli colonisation, whereas living next to a farm was associated with mcr-1-negative E coli colonisation (p=0·03, univariate test). mcr-1 could be transferred between bacteria at high frequencies (10−1 to 10−3 ), and plasmid types and MCRPEC multi-locus sequence types (MLSTs) were more variable in Guangdong than in Zhejiang and included the human pathogen ST131. MCRPEC also included 17 unreported ST clades. Interpretation In 2017, colistin will be formally banned from animal feeds in China and switched to human therapy. Infection with MRCPEC is associated with sex, immunosuppression, and previous antibiotic exposure, while colonisation is also associated with antibiotic exposure. MLST and plasmid analysis shows that MCRPEC are diversely spread throughout China and pervasive in Chinese communities. Funding National Key Basic Research Program of China, National Natural Science Foundation of China/Zhejiang, National Key Research and Development Program, and MRC, UK.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Increasing antibiotic resistance in multidrug-resistant (MDR) Gram-negative bacteria (MDR-GNB) presents significant health problems worldwide, since the vital available and effective antibiotics, ...including; broad-spectrum penicillins, fluoroquinolones, aminoglycosides, and β-lactams, such as; carbapenems, monobactam, and cephalosporins; often fail to fight MDR Gram-negative pathogens as well as the absence of new antibiotics that can defeat these "superbugs". All of these has prompted the reconsideration of old drugs such as polymyxins that were reckoned too toxic for clinical use. Only two polymyxins, polymyxin E (colistin) and polymyxin B, are currently commercially available. Colistin has re-emerged as a last-hope treatment in the mid-1990s against MDR Gram-negative pathogens due to the development of extensively drug-resistant GNB. Unfortunately, rapid global resistance towards colistin has emerged following its resurgence. Different mechanisms of colistin resistance have been characterized, including intrinsic, mutational, and transferable mechanisms.
In this review, we intend to discuss the progress over the last two decades in understanding the alternative colistin mechanisms of action and different strategies used by bacteria to develop resistance against colistin, besides providing an update about what is previously recognized and what is novel concerning colistin resistance.
Multifunctional micro‐force sensing in one device is an urgent need for the higher integration of the smaller flexible electronic device toward wearable health‐monitoring equipment, intelligent ...robotics, and efficient human–machine interface. Herein, a novel microchannel‐confined MXene‐based flexible piezoresistive sensor is demonstrated to simultaneously achieve multi‐types micro‐force sensing of pressure, sound, and acceleration. Benefiting from the synergistically confined effect of the fingerprint‐microstructured channel and the accordion‐microstructured MXene materials, the as‐designed sensor remarkably endows a low detection limit of 9 Pa, a high sensitivity of 99.5 kPa−1, and a fast response time of 4 ms, as well as non‐attenuating durability over 10 000 cycles. Moreover, the fabricated sensor is multifunctionally capable of sensing sounds, micromotion, and acceleration in one device. Evidently, such a multifunctional sensing characteristic can highlight the bright prospect of the microchannel‐confined MXene‐based micro‐force sensor for the higher integration of flexible electronics.
Benefiting from the synergistically confined effect of the fingerprint‐microstructured channel and the accordion‐microstructured MXene materials, the fabricated multifunctional micro‐force sensor can not only can reach a high sensitivity (99.5 kPa−1), low‐pressure detection (9 Pa), and fast response time (4 ms), but also be used for sensing sounds, wrist pulse, and even the acceleration of the host.
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Nowadays the development of machine vision is oriented toward real-time applications such as autonomous driving. This demands a hardware solution with low latency, high energy efficiency, and good ...reliability. Here, we demonstrate a robust and self-powered in-sensor computing paradigm with a ferroelectric photosensor network (FE-PS-NET). The FE-PS-NET, constituted by ferroelectric photosensors (FE-PSs) with tunable photoresponsivities, is capable of simultaneously capturing and processing images. In each FE-PS, self-powered photovoltaic responses, modulated by remanent polarization of an epitaxial ferroelectric Pb(Zr
Ti
)O
layer, show not only multiple nonvolatile levels but also sign reversibility, enabling the representation of a signed weight in a single device and hence reducing the hardware overhead for network construction. With multiple FE-PSs wired together, the FE-PS-NET acts on its own as an artificial neural network. In situ multiply-accumulate operation between an input image and a stored photoresponsivity matrix is demonstrated in the FE-PS-NET. Moreover, the FE-PS-NET is faultlessly competent for real-time image processing functionalities, including binary classification between 'X' and 'T' patterns with 100% accuracy and edge detection for an arrow sign with an F-Measure of 1 (under 365 nm ultraviolet light). This study highlights the great potential of ferroelectric photovoltaics as the hardware basis of real-time machine vision.
Formation of enhanced geothermal systems (EGS) is the necessary approach to obtain geothermal energy efficiently. In-situ stress, nature of reservoir physical properties and fracturing methods will ...affect the artificial fracture morphology after reservoir stimulation. A three-dimension thermal coupled seepage model of fractured media was established to simulate the influence of fracture morphology on heat mining performance of EGS, considering the pressure- and temperature-dependent physical properties of working medium. The results indicate that formation of complex fracture network is favorable for heat mining. Production mass flow in Case1 with complex fracture network enhances nearly 2.5 times comparing to the unenhanced model at exploitation beginning. The total net energy rate will up to 44 MW and be maintained above 10 MW for 5 years. The system impedance can be effectively reduced, however the sustainable heat mining duration decreased to 30 years. The increase in length and number of branch fractures is expected. While increasing the width of branch fractures deliberately has little effect on the exploitation of EGS. Finally, we investigate the adaptability of employing supercritical CO2 in EGS with complex fracture network. Production mass flow will be enhanced 3–5 times compared with water, but the stability is poor, total net energy rate decrease from 90 MW to 3 MW over the 10-year operation period.
•A three-dimension thermal coupled seepage model of fractured media for different fracture morphology is established.•Influence of different artificial fracture morphology on heat mining performance in EGS is firstly investigated.•Effect of reactivated length and reactivated width of branch fractures on heat mining performance is studied.•Adaptability of employing supercritical CO2 in EGS with complex fracture network is investigated for the first time.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
By HDR (hot dry rock) fracturing the deep buried geothermal energy can be efficiently extracted from the established EGS (enhanced geothermal system). While the fracture initiation and propagation is ...subjected to the interaction of cryogenic induced thermal stress and liquid pressure. Based on the meso-damage mechanics, elastic thermodynamics and Biot seepage mechanics, a mesoscopic thermo-hydro-mechanical-damage coupling model (THM-damage) is proposed to analyze the fracturing stimulation in HDR. Firstly, the mathematical model and numerical implementation method is validated by high-temperature granite fracturing experiments. Secondly, the action mechanism of thermal stress in hydraulic fracturing of HDR is discussed. Thirdly, the evolution of multiple physical fields during the initiation and propagation of HDR fracturing is researched. Finally, the effects of various parameters on HDR fracturing process are also studied. The results indicate that when the rock temperature exceeds 200 °C the fracture network can be formed by hydraulic fracturing, which extends along the direction perpendicular to the minimum in-situ stress. Increasing rock temperature can reduce fracture initiation pressure and rock failure pressure. The heat transfer coefficient between fracturing fluid and rock and the rock Young’s modulus have influence on the fracture morphology during HDR fracturing under thermal stress.
•High-temperature granite fracturing experiments under triaxial stress are conducted to validate the THM-damage model.•Action mechanism of thermal stress in HDR fracturing is discussed.•Evolution of temperature, seepage, stress and damage field during HDR fracturing are researched.•Effects of various parameters on fracture morphology of HDR fracturing are studied.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Accumulating documents have revealed that microRNAs (miRNAs) play critical roles in the development and progression of tumors. MiR-429 has been reported to be involved in regulating various cellular ...processes. However, its biological role and underlying mechanism in hepatocellular carcinoma (HCC) still need to be further studied. The present study aimed to investigate the function of miR-429 in the progression of HCC. In terms of this paper, it was found that miR-429 was down-regulated in HCC tissues and cells. After being transfected with miR-429 mimics, miR-429 decreased the migratory capacity and reversed the EMT to MET in HCC cells. RAB23 was confirmed as a target of miR-429. Rescue assays further verified that the function of miR-429 in HCC cells was exerted through targeting RAB23. In general, it was concluded that the signal pathway miR-429/RAB23 might be a potential target for HCC treatment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Plasmonic nanostructures have attracted considerable attention for their ability to couple with light and provide strong electromagnetic energy confinement at subwavelength dimensions. The absorbed ...portion of the captured electromagnetic energy can lead to significant heating of both the nanostructure and its surroundings, resulting in a rich set of nanoscale thermal processes that defines the subfield of thermoplasmonics with applications ranging from nanochemistry and nanobiology to optoelectronics. Recently, phononic nanostructures have started to attract attention as a platform for manipulation of phonons, enabling control over heat propagation and/or mechanical vibrations. The complex interaction phenomena between photons, electrons, and phonons require appropriate modelling strategies to design nanodevices that simultaneously explore and exploit the optical, thermal, and mechanical degrees of freedom. Examples of such devices are micro‐ and nanoscale opto‐thermo‐mechanical systems for sensing, imaging, energy conversion, and harvesting applications. Here, an overview of the fundamental theory and concepts crucial to the modelling of plasmo‐phonon devices is provided. Particular attention is given to micro‐ and nanoscale modelling frameworks, highlighting their validity ranges and the experimental works that contributed to their validation and led to compelling applications. Finally, an open‐ended outlook focused on emerging applications at the intersection between plasmonics and phononics is presented.
Improved nanofabrication techniques have recently advanced the photoinduced control of heat and vibrations through the interaction between photons, electrons, and phonons. This review summarizes the recent developments in plasmonics and phononics and provides a roadmap for their integration and future endeavors in the field of plasmo‐phononics.
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