Accelerate Single Image Super-Resolution Using Object Detection Process

Image Super-Resolution(SR)research has achieved great success with powerful neural networks.The deeper networks with more parameters improve the restoration quality but add the computation complexity,which means more inference time would be cost,hindering image SR from practical usage.Noting the spatial distribution of the objects or things in images,a twostage local objects SR system is proposed,which consists of two modules,the object detection module and the SR module.Firstly,You Only Look Once(YOLO),which is efficient in generic object detection tasks,is selected to detect the input images for obtaining objects of interest,then put them into the SR module and output corresponding High-Resolution(HR)subimages.The computational power consumption of image SR is optimized by reducing the resolution of input images.In addition,we establish a dataset,TrafficSign500,for our experiment.Finally,the performance of the proposed system is evaluated under several State-Of-The-Art(SOTA)YOLOv5 and SISR models.Results show that our system can achieve a tremendous computation improvement in image SR.

层状K_(x)MnO_(2)基钾离子电池正极材料的研究现状及发展趋势

钾离子电池具有资源丰富、价格便宜等优点,并且与锂离子电池原理相似,是目前取代锂离子电池成为大型储能系统合适的候选者.正极材料对钾离子电池性能起着关键作用,其中层状K_(x)MnO_(2)基正极材料因其高比容量、环境友好、成本低廉、独特的二维钾离子扩散通道而备受关注.但大尺寸的K^(+)在充放电过程中的反复脱嵌会导致结构破坏,并且Mn^(3+)产生的Jahn-Teller效应导致结构畸变,容量快速下降,商业应用难度较大.本文从K_(x)MnO_(2)材料层状结构调控出发,系统总结了K_(x)MnO_(2)基正极材料的制备方法,重点综述了单金属掺杂、双金属掺杂和碱金属掺杂等三种掺杂改性策略,总结阐述了K_(x)MnO_(2)基正极材料在现阶段研究中存在的主要挑战并进一步展望了其未来发展方向,可望为开发高效稳定的钾离子电池提供理论参考.

Effects of Load on Dry Sliding Wear Behavior of Mg–Gd–Zn–Zr Alloys

Dry sliding wear tests on as-cast and T6-treated Mg–3Gd–1Zn–0.4Zr(wt%, GZ31K) and Mg–6Gd–1Zn–0.4Zr(wt%, GZ61K) alloys were performed using a ball-on-disk configuration at room temperature. Friction coefficient and wear rate of the alloys were measured under three different applied loads(50 N, 100 N, and 200 N, respectively). Worn surface morphologies were analyzed using a scanning electron microscope(SEM) coupled with an energy dispersive spectrometer(EDS). It is found that the friction coefficient of the alloys decreases with increasing load, except the as-cast GZ61 K. The wear rates of the as-cast Mg–Gd–Zn–Zr alloys increase with the increase of the load. However, the wear rates of the T6-treated Mg–Gd–Zn–Zr alloys first increase because of the participation of a large amount of needle-like precipitates, but then decline due to obvious work hardening. The wear mechanisms of abrasion, plastic deformation, oxidation, adhesion and delamination are detected. Abrasion dominates the wear mechanism under the low load; whereas, adhesion is the main wear mechanism under intermediate load, and plastic deformation has great effect on the wear rate under high applied load.

Acoustofluidic separation enables early diagnosis of traumatic brain injury based on circulating exosomes

Traumatic brain injury(TBI)is a global cause of morbidity and mortality.Initial management and risk stratification of patients with TBI is made difficult by the relative insensitivity of screening radiographic studies as well as by the absence of a widely available,noninvasive diagnostic biomarker.In particular,a blood-based biomarker assay could provide a quick and minimally invasive process to stratify risk and guide early management strategies in patients with mild TBI(mTBI).Analysis of circulating exosomes allows the potential for rapid and specific identification of tissue injury.By applying acoustofluidic exosome separation—which uses a combination of microfluidics and acoustics to separate bioparticles based on differences in size and acoustic properties—we successfully isolated exosomes from plasma samples obtained from mice after TBI.Acoustofluidic isolation eliminated interference from other blood components,making it possible to detect exosomal biomarkers for TBI via flow cytometry.Flow cytometry analysis indicated that exosomal biomarkers for TBI increase in the first 24 h following head trauma,indicating the potential of using circulating exosomes for the rapid diagnosis of TBI.Elevated levels of TBI biomarkers were only detected in the samples separated via acoustofluidics;no changes were observed in the analysis of the raw plasma sample.This finding demonstrated the necessity of sample purification prior to exosomal biomarker analysis.Since acoustofluidic exosome separation can easily be integrated with downstream analysis methods,it shows great potential for improving early diagnosis and treatment decisions associated with TBI.

Acoustofluidics for simultaneous nanopartide-based drug loading and exosome encapsulation

Nanocarrier and exosome encapsulation has been found to significantly increase the efficacy of targeted drug delivery while also minimizing unwanted side effects.However,the development of exosome-encapsulated drug nanocarriers is limited by low drug loading efficiencies and/or complex,time-consuming drug loading processes.Herein,we have developed an acoustofluidic device that simultaneously performs both drug loading and exosome encapsulation.By synergistically leveraging the acoustic radiation force,acoustic microstreaming,and shear stresses in a rotating droplet,the concentration,and fusion of exosomes,drugs,and porous silica nanoparticles is achieved.The final product consists of drug-loaded silica nanocarriers that are encased within an exosomal membrane.The drug loading efficiency is significantly improved,with nearly 30%of the free drug(e.g.,doxorubicin)molecules loaded into the nanocarriers.Furthermore,this acoustofluidic drug loading system circumvents the need for complex chemical modification,allowing drug loading and encapsulation to be completed within a matter of minutes.These exosome-encapsulated nanocarriers exhibit excellent efficiency in intracellular transport and are capable of significantly inhibiting tumor cell proliferation.By utilizing physical forces to rapidly generate hybrid nanocarriers,this acoustofluidic drug loading platform wields the potential to significantly impact innovation in both drug delivery research and applications.

Electrochemical micro-aptasensors for exosome detection based on hybridization chain reaction amplification

Exosomes are cell-derived nanovesicles that have recently gained popularity as potential biomarkers in liquid biopsies due to the large amounts of molecular cargo they carry,such as nucleic acids and proteins.However,most existing exosome-based analytical sensing methods struggle to achieve high sensitivity and high selectivity simultaneously.In this work,we present an electrochemical micro-aptasensor for the highly sensitive detection of exosomes by integrating a micropatterned electrochemical aptasensor and a hybridization chain reaction(HCR)signal amplification method.Specifically,exosomes are enriched on CD63 aptamer-functionalized electrodes and then recognized by HCR products with avidin-horseradish peroxidase(HRP)attached using EpCAM aptamers as bridges.Subsequently,the current signal that is generated through the enzyme reaction between the HRP enzyme and 3,3,,5/5,-tetramethylbenzidine(TMB)/H_(2)0_(2) directly correlates to the amount of bound HRP on the HCR products and thus to the number of target exosomes.By introducing anti-EpCAM aptamers,micro-aptasensors can detect cancerous exosomes with high specificity.Due to the micropatterned electrodes and HCR dual-amplification strategy,the micro-aptasensors achieve a linear detection response for a wide range of exosome concentrations from 2.5×10^(3) to 1×10^(7) exosomes/mL,with a detection limit of 5×10^(2) exosomes/mL.Moreover,our method successfully detects lung cancer exosomes in serum samples of early-stage and late-stage lung cancer patients,showcasing the great potential for early cancer diagnosis.

CONTROLLABILITY OF QUASI-LINEAR IMPULSIVE FUNCTIONAL BOUNDARY VALUE PROBLEMS

By employing the Schauder fixed-point theorem, we establish new sufficient conditions for the controllability of impulsive functional boundary value problems.

Contribution of alternative splicing to breast cancer metastasis

Alternative splicing is a major contributor to transcriptome and proteome diversity in eukaryotes. Comparing to normal samples, about 30% more alternative splicing events were recently identified in 32 cancer types included in The Cancer Genome Atlas database. Some alternative splicing isoforms and their encoded proteins contribute to specific cancer hallmarks. In this review, we will discuss recent progress regarding the contributions of alternative splicing to breast cancer metastasis. We plan to dissect the role of MTDH, CD44 and their interaction with other mRNA splicing factors. We believe an in-depth understanding of the mechanism underlying the contribution of splicing to breast cancer metastasis will provide novel strategies to the management of breast cancer.

Aerosol jet printing of surface acoustic wave microfluidic devices

The addition of surface acoustic wave(SAW)technologies to microfluidics has greatly advanced lab-on-a-chip applications due to their unique and powerful attributes,including high-precision manipulation,versatility,integrability,biocompatibility,contactless nature,and rapid actuation.However,the development of SAW microfluidic devices is limited by complex and time-consuming micro/nanofabrication techniques and access to cleanroom facilities for multistep photolithography and vacuum-based processing.To simplify the fabrication of SAW microfluidic devices with customizable dimensions and functions,we utilized the additive manufacturing technique of aerosol jet printing.We successfully fabricated customized SAW microfluidic devices of varying materials,including silver nanowires,graphene,and poly(3,4-ethylenedioxythiophene)polystyrene sulfonate(PEDOT:PSS).To characterize and compare the acoustic actuation performance of these aerosol jet printed SAW microfluidic devices with their cleanroom-fabricated counterparts,the wave displacements and resonant frequencies of the different fabricated devices were directly measured through scanning laser Doppler vibrometry.Finally,to exhibit the capability of the aerosol jet printed devices for lab-on-a-chip applications,we successfully conducted acoustic streaming and particle concentration experiments.Overall,we demonstrated a novel solution-based,direct-write,single-step,cleanroom-free additive manufacturing technique to rapidly develop SAW microfluidic devices that shows viability for applications in the fields of biology,chemistry,engineering,and medicine.