基于Ghost-YOLOv5s的SAR图像舰船目标检测

基于星载合成孔径雷达(synthetic aperture radar,SAR)图像的舰船目标检测中,为了平衡模型大小与检测精度,提出了一种基于Ghost卷积的SAR图像舰船目标检测方法Ghost-YOLOv5s。在YOLOv5s的颈部引入Ghost卷积,以减少模型参数和压缩模型体积;将高效的通道注意力机制(efficient channel attention,ECA)融入到颈部的C3模块里,以突出重要特征,从而保持较高的检测性能;使用SIoU损失函数替换原来的CIoU损失函数,以减少预测框和真实框之间的偏差,提高检测算法精度。实验结果表明,在SSDD遥感数据集上,改进模型与YOLOv5s相比,模型参数量减少了6.28%,模型体积减小了6.21%,检测精度达到了98.21%,实现了模型大小与检测精度的平衡。

基于Ghost-SE-Res2Net的多模型融合语音唤醒词检测方法

语音唤醒词检测(WWD)是语音交互中的关键技术,选择合适大小的检测窗对WWD性能的影响很大。提出一种新的多模型融合方法,通过融合小检测窗和大检测窗的检测结果来提高WWD性能。多模型融合方法包含两个分类模型,分别使用小检测窗和大检测窗,均基于轻量化的挤压与激励残差网络(SE-Res2Net)模块,即GhostSE-Res2Net,SE-Res2Net结构的多尺度机制可显著提升WWD的能力。在Ghost-SE-Res2Net中,首先使用Ghost卷积替换SE-Res2Net中的普通卷积以降低模型参数量,然后使用注意力池化层替换SE-Res2Net中的全局平均池化层进一步提升WWD能力。在实际检测时融合连续3个小检测窗模型的检测结果的最大值和1个大检测窗模型的检测结果,来判断唤醒词是否被触发。在训练时引入困难样本挖掘算法,选择性地学习较难检测的唤醒词信息以提高分类模型的检测性能。在包含2个唤醒词的Mobvoi数据集上评估系统性能,实验结果表明,在每小时0.5次错误唤醒的情况下,该系统在2个唤醒词上的错误拒绝率分别为0.46%和0.43%,实现了与先进基线相似的性能,并且系统参数量比基线少31%。

眼斑双锯鱼(Amphiprion ocellaris)发育中体色花纹时序发生的色素细胞变化和控制基因表达的分析Ⅱ.仔稚幼鱼时期

眼斑双锯鱼(Amphiprion ocellaris)属于鲈形目、雀鲷科、双锯鱼属,是热带珊瑚礁观赏鱼类的首选品种,其不同发育时期各种色素细胞的动态变化及其控制基因表达情况有待深入研究。记录了眼斑双锯鱼仔稚幼鱼体色花纹模式建成的发育过程,对比不同发育时期体色变化的特点,筛选出仔稚幼鱼时期体色花纹变化较为明显的9个发育时期,并利用荧光定量PCR检测了眼斑双锯鱼各发育时期的10个体色控制基因的表达情况。结果显示:眼斑双锯鱼的体色发生存在明显的时序性,仔鱼时期鱼体呈现半透明状,黑色素细胞排列在身体两侧,随着生长发育数量逐渐增多;稚鱼时期,体表开始出现红色素细胞和黄色素细胞,身体慢慢变得不透明,9 dph开始出现第一道条纹,虹彩色素细胞数量逐渐增多,10 dph时期观察到第二道条纹出现;幼鱼时期,三道白色条纹完全形成,体表的橙红色和白色条纹被黑色素细胞分隔开来,界线逐渐清晰,长成完整的花纹。结合荧光定量PCR结果分析发现:在仔稚幼鱼阶段,10个体色控制基因在各发育时期均有表达,不同功能分类的基因在不同发育时期的表达变化趋势差异较大,在仔稚幼鱼前期表达量变化较大的基因主要为TYR、Dct、Ednrb、Sox10等与黑色素细胞迁移、分化、合成相关的基因;随着幼鱼不断的生长发育,白色条纹逐条出现,与虹彩色素细胞相关的Fms、Foxd3等基因也开始出现表达量显著上升的趋势。

One-and Multi-dimensional CWENOZ Reconstructions for Implementing Boundary Conditions Without Ghost Cells

We address the issue of point value reconstructions from cell averages in the context of third-order finite volume schemes,focusing in particular on the cells close to the boundaries of the domain.In fact,most techniques in the literature rely on the creation of ghost cells outside the boundary and on some form of extrapolation from the inside that,taking into account the boundary conditions,fills the ghost cells with appropriate values,so that a standard reconstruction can be applied also in the boundary cells.In Naumann et al.(Appl.Math.Comput.325:252–270.https://doi.org/10.1016/j.amc.2017.12.041,2018),motivated by the difficulty of choosing appropriate boundary conditions at the internal nodes of a network,a different technique was explored that avoids the use of ghost cells,but instead employs for the boundary cells a different stencil,biased towards the interior of the domain.In this paper,extending that approach,which does not make use of ghost cells,we propose a more accurate reconstruction for the one-dimensional case and a two-dimensional one for Cartesian grids.In several numerical tests,we compare the novel reconstruction with the standard approach using ghost cells.

Metabolic and proteostatic differences in quiescent and active neural stem cells

Adult neural stem cells are neurogenesis progenitor cells that play an important role in neurogenesis.Therefore,neural regeneration may be a promising target for treatment of many neurological illnesses.The regenerative capacity of adult neural stem cells can be chara cterized by two states:quiescent and active.Quiescent adult neural stem cells are more stable and guarantee the quantity and quality of the adult neural stem cell pool.Active adult neural stem cells are chara cterized by rapid proliferation and differentiation into neurons which allow for integration into neural circuits.This review focuses on diffe rences between quiescent and active adult neural stem cells in nutrition metabolism and protein homeostasis.Furthermore,we discuss the physiological significance and underlying advantages of these diffe rences.Due to the limited number of adult neural stem cells studies,we refe rred to studies of embryonic adult neural stem cells or non-mammalian adult neural stem cells to evaluate specific mechanisms.

The MORC2 p.S87L mutation reduces proliferation of pluripotent stem cells derived from a patient with the spinal muscular atrophy-like phenotype by inhibiting proliferation-related signaling pathways

Mutations in the microrchidia CW-type zinc finger protein 2(MORC2)gene are the causative agent of Charcot-Marie-Tooth disease type 2Z(CMT2Z),and the hotspot mutation p.S87L is associated with a more seve re spinal muscular atrophy-like clinical phenotype.The aims of this study were to determine the mechanism of the severe phenotype caused by the MORC2 p.S87L mutation and to explore potential treatment strategies.Epithelial cells were isolated from urine samples from a spinal muscular atrophy(SMA)-like patient[MORC2 p.S87L),a CMT2Z patient[MORC2 p.Q400R),and a healthy control and induced to generate pluripotent stem cells,which were then differentiated into motor neuron precursor cells.Next-generation RNA sequencing followed by KEGG pathway enrichment analysis revealed that differentially expressed genes involved in the PI3K/Akt and MAP K/ERK signaling pathways were enriched in the p.S87L SMA-like patient group and were significantly downregulated in induced pluripotent stem cells.Reduced proliferation was observed in the induced pluripotent stem cells and motor neuron precursor cells derived from the p.S87L SMA-like patient group compared with the CMT2Z patient group and the healthy control.G0/G1 phase cell cycle arrest was observed in induced pluripotent stem cells derived from the p.S87L SMA-like patient.MORC2 p.S87Lspecific antisense oligonucleotides(p.S87L-ASO-targeting)showed significant efficacy in improving cell prolife ration and activating the PI3K/Akt and MAP K/ERK pathways in induced pluripotent stem cells.Howeve r,p.S87L-ASO-ta rgeting did not rescue prolife ration of motor neuron precursor cells.These findings suggest that downregulation of the PI3K/Akt and MAP K/ERK signaling pathways leading to reduced cell proliferation and G0/G1 phase cell cycle arrest in induced pluripotent stem cells might be the underlying mechanism of the severe p.S87L SMA-like phenotype.p.S87L-ASO-targeting treatment can alleviate disordered cell proliferation in the early stage of pluripotent stem cell induction.

Evaluation of the intracellular lipid-lowering effect of polyphenols extract from highland barley in HepG2 cells

Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4.

Cell metabolism pathways involved in the pathophysiological changes of diabetic peripheral neuropathy

Diabetic peripheral neuropathy is a common complication of diabetes mellitus.Elucidating the pathophysiological metabolic mechanism impels the generation of ideal therapies.However,existing limited treatments for diabetic peripheral neuropathy expose the urgent need for cell metabolism research.Given the lack of comprehensive understanding of energy metabolism changes and related signaling pathways in diabetic peripheral neuropathy,it is essential to explore energy changes and metabolic changes in diabetic peripheral neuropathy to develop suitable treatment methods.This review summarizes the pathophysiological mechanism of diabetic peripheral neuropathy from the perspective of cellular metabolism and the specific interventions for different metabolic pathways to develop effective treatment methods.Various metabolic mechanisms(e.g.,polyol,hexosamine,protein kinase C pathway)are associated with diabetic peripheral neuropathy,and researchers are looking for more effective treatments through these pathways.

Model reduction of fractional impedance spectra for time–frequency analysis of batteries, fuel cells, and supercapacitors

Joint time–frequency analysis is an emerging method for interpreting the underlying physics in fuel cells,batteries,and supercapacitors.To increase the reliability of time–frequency analysis,a theoretical correlation between frequency-domain stationary analysis and time-domain transient analysis is urgently required.The present work formularizes a thorough model reduction of fractional impedance spectra for electrochemical energy devices involving not only the model reduction from fractional-order models to integer-order models and from high-to low-order RC circuits but also insight into the evolution of the characteristic time constants during the whole reduction process.The following work has been carried out:(i)the model-reduction theory is addressed for typical Warburg elements and RC circuits based on the continued fraction expansion theory and the response error minimization technique,respectively;(ii)the order effect on the model reduction of typical Warburg elements is quantitatively evaluated by time–frequency analysis;(iii)the results of time–frequency analysis are confirmed to be useful to determine the reduction order in terms of the kinetic information needed to be captured;and(iv)the results of time–frequency analysis are validated for the model reduction of fractional impedance spectra for lithium-ion batteries,supercapacitors,and solid oxide fuel cells.In turn,the numerical validation has demonstrated the powerful function of the joint time–frequency analysis.The thorough model reduction of fractional impedance spectra addressed in the present work not only clarifies the relationship between time-domain transient analysis and frequency-domain stationary analysis but also enhances the reliability of the joint time–frequency analysis for electrochemical energy devices.

Joint Authentication Public Network Cryptographic Key Distribution Protocol Based on Single Exposure Compressive Ghost Imaging

In the existing ghost-imaging-based cryptographic key distribution(GCKD)protocols,the cryptographic keys need to be encoded by using many modulated patterns,which undoubtedly incurs long measurement time and huge memory consumption.Given this,based on snapshot compressive ghost imaging,a public network cryptographic key distribution protocol is proposed,where the cryptographic keys and joint authentication information are encrypted into several color block diagrams to guarantee security.It transforms the previous single-pixel sequential multiple measurements into multi-pixel single exposure measurements,significantly reducing sampling time and memory storage.Both simulation and experimental results demonstrate the feasibility of this protocol and its ability to detect illegal attacks.Therefore,it takes GCKD a big step closer to practical applications.

Cell replacement with stem cell-derived retinal ganglion cells from different protocols

Glaucoma,characterized by a degenerative loss of retinal ganglion cells,is the second leading cause of blindness worldwide.There is currently no cure for vision loss in glaucoma because retinal ganglion cells do not regenerate and are not replaced after injury.Human stem cell-derived retinal ganglion cell transplant is a potential therapeutic strategy for retinal ganglion cell degenerative diseases.In this review,we first discuss a 2D protocol for retinal ganglion cell differentiation from human stem cell culture,including a rapid protocol that can generate retinal ganglion cells in less than two weeks and focus on their transplantation outcomes.Next,we discuss using 3D retinal organoids for retinal ganglion cell transplantation,comparing cell suspensions and clusters.This review provides insight into current knowledge on human stem cell-derived retinal ganglion cell differentiation and transplantation,with an impact on the field of regenerative medicine and especially retinal ganglion cell degenerative diseases such as glaucoma and other optic neuropathies.

The combined application of stem cells and three-dimensional bioprinting scaffolds for the repair of spinal cord injury

Spinal cord injury is considered one of the most difficult injuries to repair and has one of the worst prognoses for injuries to the nervous system.Following surgery,the poor regenerative capacity of nerve cells and the generation of new scars can make it very difficult for the impaired nervous system to restore its neural functionality.Traditional treatments can only alleviate secondary injuries but cannot fundamentally repair the spinal cord.Consequently,there is a critical need to develop new treatments to promote functional repair after spinal cord injury.Over recent years,there have been seve ral developments in the use of stem cell therapy for the treatment of spinal cord injury.Alongside significant developments in the field of tissue engineering,three-dimensional bioprinting technology has become a hot research topic due to its ability to accurately print complex structures.This led to the loading of three-dimensional bioprinting scaffolds which provided precise cell localization.These three-dimensional bioprinting scaffolds co uld repair damaged neural circuits and had the potential to repair the damaged spinal cord.In this review,we discuss the mechanisms underlying simple stem cell therapy,the application of different types of stem cells for the treatment of spinal cord injury,and the different manufa cturing methods for three-dimensional bioprinting scaffolds.In particular,we focus on the development of three-dimensional bioprinting scaffolds for the treatment of spinal cord injury.

TM9SF1 promotes bladder cancer cell growth and infiltration

BACKGROUND Bladder cancer(BC)is the most common urological tumor.It has a high recur-rence rate,displays tutor heterogeneity,and resists chemotherapy.Furthermore,the long-term survival rate of BC patients has remained unchanged for decades,which seriously affects the quality of patient survival.To improve the survival rate and prognosis of BC patients,it is necessary to explore the molecular mechanisms of BC development and progression and identify targets for treatment and intervention.Transmembrane 9 superfamily member 1(TM9SF1),also known as MP70 and HMP70,is a member of a family of nine transmembrane superfamily proteins,which was first identified in 1997.TM9SF1 can be expressed in BC,but its biological function and mechanism in BC are not clear.AIM To investigate the biological function and mechanism of TM9SF1 in BC.Overexpression of TM9SF1 increased the in vitro proliferation,migration,and invasion of BC cells by promoting the entry of BC cells into the G2/M phase.Silencing of TM9SF1 inhibited in vitro proliferation,migration,and invasion of BC cells and blocked BC cells in the G1 phase.CONCLUSION TM9SF1 may be an oncogene in BC.

Long non-coding RNA H19 regulates neurogenesis of induced neural stem cells in a mouse model of closed head injury

Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury.

Mechanism of inflammatory response and therapeutic effects of stem cells in ischemic stroke:current evidence and future perspectives

Ischemic stroke is a leading cause of death and disability worldwide,with an increasing trend and tendency for onset at a younger age.China,in particular,bears a high burden of stroke cases.In recent years,the inflammatory response after stroke has become a research hotspot:understanding the role of inflammatory response in tissue damage and repair following ischemic stroke is an important direction for its treatment.This review summarizes several major cells involved in the inflammatory response following ischemic stroke,including microglia,neutrophils,monocytes,lymphocytes,and astrocytes.Additionally,we have also highlighted the recent progress in various treatments for ischemic stroke,particularly in the field of stem cell therapy.Overall,understanding the complex interactions between inflammation and ischemic stroke can provide valuable insights for developing treatment strategies and improving patient outcomes.Stem cell therapy may potentially become an important component of ischemic stroke treatment.

Promoting Sickle Cell Trait Awareness and Education: A Typology of Interventions in the United States to Inform Ongoing Efforts to Patients and Providers

Research Background: Sickle cell trait has no treatment or cure and predominantly affects people who are Black, but can affect anyone of any race or ethnicity. While commonly incorrectly considered benign by providers and the public, people with a sickle cell trait experience life-threatening outcomes that are exacerbated by extreme conditions. There is a severe lack of awareness and understanding of sickle cell trait and the associated health complications among sickle cell trait carriers and healthcare providers. Purpose/Aim: Interventions that aim to improve awareness of sickle cell trait differ in approaches and are not well documented in the literature. This typology aims to highlight current efforts to inform targeted interventions that raise awareness through consistent messaging, educate people and providers on sickle cell trait and the related health complications, and support the design and implementation of comprehensive sickle cell trait awareness initiatives. Methods: We conducted a scoping review of United States-based sickle cell trait interventions and performed a content analysis to identify the categories and characteristics of these efforts. We then organized the results into a typology according to established protocols. Results: Among 164 interventions, twenty-five (15%) met the typology inclusion criteria described above and were grouped into categories: Seven of twenty-five interventions were Educational Interventions (28%), three of twenty-five interventions (12%) were Combined Screening and Educational-Based Interventions, eight of twenty-five interventions (32%) were Policy and Guideline-Based Intervention, and six of twenty-five interventions (24%) were Sickle Cell Trait Organization-Led Interventions. Conclusions: There is a lack of consistency in messaging across interventions whether delivered by credible healthcare institutions or national organizations, which can result in lack of education and awareness and confusion around sickle cell trait. Categorizing interventions through a typology allows clarity and informs consistency in messaging, which should be at the forefront of future sickle cell trait efforts.

High glucose microenvironment and human mesenchymal stem cell behavior

High glucose(HG)culture conditions in vitro and persistent exposure to hyperglycemia in diabetes patients are detrimental to stem cells,analogous to any other cell type in our body.It interferes with diverse signaling pathways,i.e.mammalian target of rapamycin(mTOR)-phosphoinositide 3-kinase(PI3K)-Akt signaling,to impact physiological cellular functions,leading to low cell survival and higher cell apoptosis rates.While elucidating the underlying mechanism responsible for the apoptosis of adipose tissue-derived mesenchymal stem cells(MSCs),a recent study has shown that HG culture conditions dysregulate mTORPI3K-Akt signaling in addition to mitochondrial malfunctioning due to defective mitochondrial membrane potential(MtMP)that lowers ATP production.This organelle-level dysfunction energy-starves the cells and increases oxidative stress and ultrastructural abnormalities.Disruption of the mitochondrial electron transport chain produces an altered mitochondrial NAD+/NADH redox state as evidenced by a low NAD+/NADH ratio that primarily contributes to the reduced cell survival in HG.Some previous studies have also reported altered mitochondrial membrane polarity(causing hyperpolarization)and reduced mitochondrial cell mass,leading to perturbed mitochondrial homeostasis.The hostile microenvironment created by HG exposure creates structural and functional changes in the mitochondria,altering their bioenergetics and reducing their capacity to produce ATP.These are significant data,as MSCs are extensively studied for tissue regeneration and restoring their normal functioning in cell-based therapy.Therefore,MSCs from hyperglycemic donors should be cautiously used in clinical settings for cell-based therapy due to concerns of their poor sur-vival rates and increased rates of post engraftment proliferation.As hypergly-cemia alters the bioenergetics of donor MSCs,rectifying the loss of MtMP may be an excellent target for future research to restore the normal functioning of MSCs in hyperglycemic patients.

Emerging strategies for nerve repair and regeneration in ischemic stroke:neural stem cell therapy

Ischemic stroke is a major cause of mortality and disability worldwide,with limited treatment options available in clinical practice.The emergence of stem cell therapy has provided new hope to the field of stroke treatment via the restoration of brain neuron function.Exogenous neural stem cells are beneficial not only in cell replacement but also through the bystander effect.Neural stem cells regulate multiple physiological responses,including nerve repair,endogenous regeneration,immune function,and blood-brain barrier permeability,through the secretion of bioactive substances,including extracellular vesicles/exosomes.However,due to the complex microenvironment of ischemic cerebrovascular events and the low survival rate of neural stem cells following transplantation,limitations in the treatment effect remain unresolved.In this paper,we provide a detailed summary of the potential mechanisms of neural stem cell therapy for the treatment of ischemic stroke,review current neural stem cell therapeutic strategies and clinical trial results,and summarize the latest advancements in neural stem cell engineering to improve the survival rate of neural stem cells.We hope that this review could help provide insight into the therapeutic potential of neural stem cells and guide future scientific endeavors on neural stem cells.

Effect of VEGF/GREDVY Modified Surface on Vascular Cells Behavior

We synthesized B-He/B-GREDVY and immobilized them on avidin-coated surfaces.To examine the immobilization of molecules in the material, the following experiments were performed:fluorescein isothiocyanate(FITC) fluorescence staining, water contact angle and atomic force microscopy(AFM) measurements. Besides, the biological evaluation experiments were also performed, such as platelets adhesion and activation, the culturing of smooth muscle cells(SMC) and endothelial cells(EC). These experimental results show that the modified surfaces could prevent the hyperproliferation of SMC, and promote the proliferation and migration of EC and EPC. Furthermore, the adding of VEGF improved the EC adhesion in a dynamic environment. Generally, it is expected that the modified surfaces could be used to accelerate the formation of the newly endothelial layer for the construction of platforms for coronary artery stent therapy.

Stem cell-based ischemic stroke therapy:Novel modifications and clinical challenges

Ischemic stroke(IS)causes severe disability and high mortality worldwide.Stem cell(SC)therapy exhibits unique therapeutic potential for IS that differs from current treatments.SC’s cell homing,differentiation and paracrine abilities give hope for neuroprotection.Recent studies on SC modification have enhanced therapeutic effects for IS,including gene transfection,nanoparticle modification,biomaterial modification and pretreatment.Thesemethods improve survival rate,homing,neural differentiation,and paracrine abilities in ischemic areas.However,many problems must be resolved before SC therapy can be clinically applied.These issues include production quality and quantity,stability during transportation and storage,as well as usage regulations.Herein,we reviewed the brief pathogenesis of IS,the“multi-mechanism”advantages of SCs for treating IS,various SC modification methods,and SC therapy challenges.We aim to uncover the potential and overcome the challenges of using SCs for treating IS and convey innovative ideas for modifying SCs.