Transplantation of human induced pluripotent stem cell derived keratinocytes accelerates deep second-degree burn wound healing

BACKGROUND Current evidence shows that human induced pluripotent stem cells(hiPSCs)can effectively differentiate into keratinocytes(KCs),but its effect on skin burn healing has not been reported.AIM To observe the effects of hiPSCs-derived KCs transplantation on skin burn healing in mice and to preliminarily reveal the underlying mechanisms.METHODS An analysis of differentially expressed genes in burn wounds based on GEO datasets GSE140926,and GSE27186 was established.A differentiation medium containing retinoic acid and bone morphogenetic protein 4 was applied to induce hiPSCs to differentiate into KCs.The expression of KCs marker proteins was detected using immunofluorescence staining.A model of a C57BL/6 mouse with deep cutaneous second-degree burn was created,and then phosphate buffered saline(PBS),hiPSCs-KCs,or hiPSCs-KCs with knockdown of COL7A1 were injected around the wound surface.The wound healing,re-epithelialization,engraftment of hiPSCs-KCs into wounds,proinflammatory factor level,and the NF-κB pathway proteins were assessed by hematoxylin-eosin staining,carboxifluorescein diacetate succinimidyl ester(CFSE)fluorescence staining,enzyme linked immunosorbent assay,and Western blotting on days 3,7,and 14 after the injection,respectively.Moreover,the effects of COL7A1 knockdown on the proliferation and migration of hiPSCs-KCs were confirmed by immunohistochemistry,EdU,Transwell,and damage repair assays.RESULTS HiPSCs-KCs could express the hallmark proteins of KCs.COL7A1 was down-regulated in burn wound tissues and highly expressed in hiPSCs-KCs.Transplantation of hiPSCs-KCs into mice with burn wounds resulted in a significant decrease in wound area,an increase in wound re-epithelialization,a decrease in proinflammatory factors content,and an inhibition of NF-κB pathway activation compared to the PBS group.The in vitro assay showed that COL7A1 knockdown could rescue the inhibition of hiPSCs-KCs proliferation and migration,providing further evidence that COL7A1 speeds up burn wound healing by limiting cell proliferation and migration.CONCLUSION In deep,second-degree burn wounds,COL7A1 can promote KC proliferation and migration while also suppressing the inflammatory response.

Mechanism of floral scent production in Osmanthus fragrans and the production and regulation of its key floral constituents,β-ionone and linalool

Sweet osmanthus(Osmanthus fragrans Lour.)is among the top ten most well-known flowers in China and is recognized as both an aromatic plant and ornamental flower.Here,manual sectioning,scanning electron microscopy,and transmission electron microscopy of sweet osmanthus petals revealed that large amounts of lipids are present inside the petal cells and on the cell surfaces.However,no secretory structures were observed.Instead,the petal cells protrude slightly outward,and the surfaces of the cells are adorned with highly regular brush-shaped hairs.The surfaces of the‘Yingui’petals possessed mostly curled and more numerous hairs,whereas the‘Dangui’petals possessed fewer brush-shaped and more sparsely arranged hairs.In addition,many granular substances were attached to the brush-shaped hairs,and the granules were denser on the hairs of the‘Yingui’petals compared to the hairs on the‘Dangui’petals.Furthermore,35 aromatic components in the‘Yingui’petals and 30 aromatic components in the‘Dangui’petals were detected via GC-MS.The main aromatic component of the‘Yingui’petals wasβ-ionone,whereas that of the‘Dangui’petals was linalool and its oxides.Transcriptome sequencing and qRT-PCR indicated that the highβ-ionone content in the‘Yingui’petals was due to the overexpression of CCD1 and CCD4 and that the high linalool content in the‘Dangui’petals was due to the overexpression of MECS,HDR,IDI1,and LIS1,which function upstream of the linalool synthetic pathway.In particular,the expression levels of CCD4 and LIS1 were upregulated by 5.5-and 5.1-fold in the‘Yingui’and‘Dangui’petals,respectively.One transcription factor(ERF61)was cloned and named,and the expression pattern of ERF61 in sweet osmanthus petals was found to be generally consistent with that of CCD4.Tobacco transformation experiments,yeast one-hybrid experiments,and electrophoretic mobility shift assays indicated that ERF61 binds to the CCD4 promoter and stimulates CCD4 expression,thereby regulating the synthesis ofβ-ionone in sweet osmanthus petals.

Calibrating the linearity between grayscale and element content for X-ray KES imaging of alloys

Doped elements in alloys significantly impact their performance.Conventional methods usually sputter the surface material of the sample,or their performance is limited to the surface of alloys owing to their poor penetration ability.The X-ray K-edge subtraction(KES)method exhibits great potential for the nondestructive in situ detection of element contents in alloys.However,the signal of doped elements usually deteriorates because of the strong absorption of the principal component and scattering of crystal grains.This in turn prevents the extensive application of X-ray KES imaging to alloys.In this study,methods were developed to calibrate the linearity between the grayscale of the KES image and element content.The methods were aimed at the sensitive analysis of elements in alloys.Furthermore,experiments with phantoms and alloys demonstrated that,after elaborate calibration,X-ray KES imaging is capable of nondestructive and sensitive analysis of doped elements in alloys.

Long noncoding RNA Pvt1 promotes the proliferation and migration of Schwann cells by sponging microRNA-214 and targeting c-Jun following peripheral nerve injury

Research has shown that long-chain noncoding RNAs(lncRNAs) are involved in the regulation of a variety of biological processes, including peripheral nerve regeneration, in part by acting as competing endogenous RNAs. c-Jun plays a key role in the repair of peripheral nerve injury. However, the precise underlying mechanism of c-Jun remains unclear. In this study, we performed microarray and bioinformatics analysis of mouse crush-injured sciatic nerves and found that the lncRNA Pvt1 was overexpressed in Schwann cells after peripheral nerve injury. Mechanistic studies revealed that Pvt1 increased c-Jun expression through sponging miRNA-214. We overexpressed Pvt1 in Schwann cells cultured in vitro and found that the proliferation and migration of Schwann cells were enhanced, and overexpression of miRNA-214 counteracted the effects of Pvt1 overexpression on Schwann cell proliferation and migration. We conducted in vivo analyses and injected Schwann cells overexpressing Pvt1 into injured sciatic nerves of mice. Schwann cells overexpressing Pvt1 enhanced the regeneration of injured sciatic nerves following peripheral nerve injury and the locomotor function of mice was improved. Our findings reveal the role of lncRNAs in the repair of peripheral nerve injury and highlight lncRNA Pvt1 as a novel potential treatment target for peripheral nerve injury.

RFID电缆中间接头无线无源湿度监测

针对电缆中间接头受潮导致的运行故障问题,提出一种基于13.56 MHz RFID技术的无源湿度监测方法。该文利用HFSS建立传感器模型,调整天线匝距使天线达到理想状态,并对天线进行谐振匹配;然后研究传感器天线在水中的传输效果及存在金属屏蔽层时金属对天线性能的影响;最后将所设计的传感器放置于中间接头内部进行性能测试。结果表明:天线匝距为0.6 mm时传感器性能最佳;在天线外部增加47μH电容可实现13.56 MHz谐振匹配;传感器天线在水中的传输效果良好;加装金属屏蔽层可解决路径上金属对传感器信号传输的抑制作用;实际测量距离可达到8.2 cm、相对湿度测量误差最大为0.48%,最大波动幅度仅为0.3%,传感器长期处于高湿度环境仍能准确测量。该方法可实现电缆中间接头内部湿度的直接、快速及无源测量,对防止电缆受潮具有一定的参考意义。

Vibration and Sound Radiation of Cylindrical Shell Covered with a Skin Made of Micro Floating Raft Arrays Excited by Turbulence

To reduce the vibration and sound radiation of underwater cylindrical shells,a skin composed of micro floating raft arrays and a compliant wall is proposed in this paper.A vibroacoustic coupling model of a finite cylindrical shell covered with this skin for the case of turbulence excitation is established based on the shell theories of Donnell.The model is solved with the modal superposition method to investigate the effects of the structural parameters of micro floating raft elements on the performance of reducing vibration and sound radiation of the cylindrical shell of this skin.The results indicate that increasing the stiffness ratio,damping ratio,mass ratio,or decreasing the interval betweenmicro floating raft elements can improve the vibration and sound radiation reduction performance of this skin over the frequency range 0∼2000 Hz.Moreover,the mean quadratic velocity level and sound radiation power level of the finite cylindrical shell with this skin can be reduced by 12.00 dB and 9.65 dB respectively compared to the finite cylindrical shell with homogeneous viscoelastic coating in the frequency range from0∼2000Hz,implying a favorable performance of this skin for reducing the vibration and sound radiation of cylindrical shells.

Computational biology in topical bioactive peptide discovery for cosmeceutical application:a concise review

Regenerative medicine and anti-aging research have made great strides at the molecular and cellular levels in dermatology and the medical aesthetic field,targeting potential treatments with skin therapeutic and intervention pathways,which make it possible to develop effective skin regeneration and repair ingredients.With the rapid development of computational biology,bioinformatics as well as artificial intelligence(A.I.),the development of new ingredients for regenerative medicine has been greatly accelerated,and the success rate has been improved.Some application cases have appeared in topical skin regeneration and repair scenarios.This review will briefly introduce the application of bioactive peptides in skin repair and anti-aging as emerging ingredients in cosmeceutics and emphasize how A.I.based computational biology technology may accelerate the development of innovative peptide molecules and ultimately translate them into potential skin regenerative and anti-aging scenarios.Typically,two research routines have been summarized and current limitations as well as directions were discussed for border applications in future research.

Application Strategy of CBR Test in Highway Engineering

California Bearing Ratio(CBR)test is highly professional and requires a high level of skills.In order to improve the accuracy of the test results,the relevant staff will not only need to understand the rules and procedures involved in the test,they would also need to be meticulous in their work to avoid human errors,provide good data support for highway engineering,and improve the overall quality of the project.Therefore,this paper presents an analysis of the application of CBR test in highway engineering,which can provide reference for engineering and promote the development of the highway industry.

黄钾铁矾对硫脲浸金的影响及草酸盐的作用机理

研究生物氧化产生的黄钾铁矾对酸性硫脲浸金的影响,并探讨草酸添加剂的作用机制。结果表明,黄钾铁矾会增加硫脲的消耗和阻碍金的溶解。黄钾铁矾能显著提高硫脲的分解,阻碍金的溶解。黄钾铁矾造成不利影响的主要原因可能是酸性溶液中黄钾铁矾释放的铁离子使溶液浆电位增加,从而加速硫脲的分解,并加剧硫脲分解产生的钝化物种对金表面的钝化作用。添加草酸盐可以有效削弱黄钾铁矾的不利影响,表现为明显降低硫脲的消耗和促进金的溶解。通过溶液电位、Zeta电位和XPS分析,揭示草酸的可能作用机理。草酸盐不仅可以通过与Fe^(3+)配位减弱Fe^(3+)与硫脲之间的相互作用,还可以通过无差别吸附和静电斥力阻止钝化产物在金表面包裹。

基于Kaczmarz算法的磁粒子成像快速重建算法研究

目的:为了解决磁粒子断层成像中系统矩阵方法成像时间长、计算复杂的问题,提出一种基于Kaczmarz算法的磁粒子成像快速重建算法。方法:首先,分析经典Kaczmarz算法及其变体算法的收敛速度,并计算在任意矩阵下的迭代次数和计算时间;其次,比较欧氏距离和余弦距离对系统数据的区分能力,并运用基于余弦距离的K-means算法来增强块Kaczmarz算法的运算能力,缩短系统矩阵重建时间并最终实现磁粒子成像快速重建。最后,通过计算机仿真实验验证提出的算法的有效性。结果:提出的算法大幅缩短了重建时间,提高了重建图像的空间分辨力和质量。结论:提出的算法可以实现磁粒子成像的快速重建,并且在处理含有噪声的数据时具备较强的重建能力。

Oxygen‑Coordinated Single Mn Sites for Efficient Electrocatalytic Nitrate Reduction to Ammonia

Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption spectroscopy.As a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(vs.reversible hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(vs.RHE)under ambient conditions.Further,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H cell.The in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.

基础护理学线上线下混合式“金课”思政教学设计与实践

在基础护理学课程中构建以课堂教学为主体,以线上平台自主学习和第二课堂社会实践为两翼的“一体两翼”式大思政育人模式,将政治认同、家国情怀、职业素养、科学精神、道德修养、法治素养、文化素养、南丁格尔精神8大核心思政元素与专业知识有机融合开展课程思政,取得了良好效果,实现了线上线下、课内课外、校内校外三维度协同育人。该课程被评为省级课程思政示范课程。

低剂量右美托咪定对老年髋部骨折术后炎症反应及谵妄的影响

目的评估预防性使用低剂量右美托咪定(dexmedetomidine,DEX)对老年髋部骨折患者术后炎症反应的影响。方法将入住重症监护病房(intensive care unit,ICU)的老年髋部骨折术后患者采用数字表法随机分配到DEX组或对照组,即刻分别给予DEX 0.1μg·kg^(-1)·h^(-1)及0.9%(质量分数)氯化钠注射液,相同液速(0.025 mL·kg^(-1)·h^(-1))静脉泵入。测定给药后0(即刻)、6、12、18 h患者血清降钙素原和白细胞介素-6浓度,记录血流动力学参数(心指数、每搏量指数、平均动脉压、心率)及谵妄的发生。结果两组间降钙素原及白细胞介素-6在各个时间点的差异无统计学意义(P>0.05),DEX组出现谵妄的例数显著低于对照组(P=0.034)。DEX组额外使用阿片类镇痛药物的例数(P=0.039)以及出现高血压的例数(P=0.012)显著低于对照组。结论低剂量DEX未显著降低老年髋部骨折患者术后的炎症指标,但有助于减少老年髋部骨折患者谵妄的发生及阿片类药物的使用。低剂量DEX对于血流力学影响较小,对术后高血压的患者可能具有一定循环保护作用。

Bayesian Filtering for High-Dimensional State-Space Models With State Partition and Error Compensation

In the era of exponential growth of data availability,the architecture of systems has a trend toward high dimensionality,and directly exploiting holistic information for state inference is not always computationally affordable.This paper proposes a novel Bayesian filtering algorithm that considers algorithmic computational cost and estimation accuracy for high-dimensional linear systems.The high-dimensional state vector is divided into several blocks to save computation resources by avoiding the calculation of error covariance with immense dimensions.After that,two sequential states are estimated simultaneously by introducing an auxiliary variable in the new probability space,mitigating the performance degradation caused by state segmentation.Moreover,the computational cost and error covariance of the proposed algorithm are analyzed analytically to show its distinct features compared with several existing methods.Simulation results illustrate that the proposed Bayesian filtering can maintain a higher estimation accuracy with reasonable computational cost when applied to high-dimensional linear systems.

High-speed silicon photonic electro-optic Kerr modulation

Silicon-based electro-optic modulators contribute to easing the integration of high-speed and low-power consumption circuits for classical optical communications and data computations.Beyond the plasma dispersion modulation,an alternative solution in silicon is to exploit the DC Kerr effect,which generates an equivalent linear electro-optical effect enabled by applying a large DC electric field.Although some theoretical and experimental studies have shown its existence in silicon,limited contributions relative to plasma dispersion have been achieved in high-speed modulation so far.This paper presents high-speed optical modulation based on the DC Kerr effect in silicon PIN waveguides.The contributions of both plasma dispersion and Kerr effects have been analyzed in different waveguide configurations,and we demonstrated that the Kerr induced modulation is dominant when a high external DC electric field is applied in PIN waveguides.High-speed optical modulation response is analyzed,and eye diagrams up to 80 Gbit/s in NRZ format are obtained under a d.c.voltage of 30 V.This work paves the way to exploit the Kerr effect to generate high-speed Pockels-like optical modulation.

ECMO辅助在肺移植围手术期的效果:单中心回顾性研究

目的探讨体外膜肺氧合(ECMO)在肺移植手术麻醉中的应用,观察其对改善麻醉效果和预后的作用。方法回顾性分析我院2017年6月至2023年3月行单肺移植或双肺移植的70例患者。根据ECMO的应用将患者分为V-V组(34例)、V-A组(14例)和非ECMO组(22例)。比较三组围手术期相关临床资料,包括手术方式、手术时间、术中血流动力学指标、术中出血量和尿量、术后ECMO撤机时间、拔管时间,以及再次插管、二次开胸止血等不良事件。结果三组患者人口学资料和病因学特征差异无统计学意义(P>0.05)。与非ECMO组比较,V-V组和V-A组术中平均肺动脉压(mPAP)、动脉血氧分压(PaO2)及二氧化碳分压(PaCO_(2))较优(P<0.05),但术中出血量更多(P<0.05)。V-V组和V-A组住院时间更短(P<0.05),再次插管几率更小(P<0.05)。结论ECMO可优化肺移植手术麻醉效果,缩短住院时间,提高危重患者生存率。但应注重其并发症的防范。ECMO是一种值得在肺移植麻醉中推广的有用辅助手段。

DDM regression analysis of the in-situ stress field in a non-linear fault zone

A multivariable regression analysis of the in-situ stress field, which considers the non-linear deformation behavior of faults in practical projects, is presented based on a newly developed three-dimensional displacement discontinuity method （DDM） program. The Bar- ton-Bandis model and the Kulhaway model are adopted as the normal and the tangential deformation model of faults, respectively, where the Mohr-Coulomb failure criterion is satisfied. In practical projects, the values of the mechanical parameters of rock and faults are restricted in a bounded range for in-situ test, and the optimal mechanical parameters are obtained from this range by a loop. Comparing with the traditional finite element method （FEM）, the DDM regression results are more accurate.

Nonlinear energy harvesting based on a modified snap-through mechanism

A modified snap-through mechanism is used in an electromagnetic energy harvester to improve its effectiveness. It mainly comprises three springs that are configured so that the potential energy of the system has two stable equilibrium points. In particular, the small vibration behavior of the harvester around one of the equilibriums is of interest. A multi-scale method(MSM) is used to analyze the frequency response curve. Two snap-through mechanisms are considered. One has both horizontal and vertical springs. The other has only horizontal springs. The frequency response curves of these two classes are compared under the same excitation and electric loading conditions. The latter exhibits more bending of the frequency response curve than the former one. The results are also validated by some numerical work. The averaged power subject to the Gaussian white noise is calculated numerically, and the results demonstrate that bi-stable energy harvesting with only horizontal springs can outperform the mechanism with both horizontal and vertical springs for the same distance between two equilibriums.

Sex-determining region Y box-containing genes: regulators and biomarkers in gynecological cancers

Sex-determining region Y box-containing genes are transcription factors with roles in multiple biological processes, including cell differentiation, proliferation, and apoptosis.Sex-determining region Y box-containing genes have also been shown to act as regulators and biomarkers in the progression of many different cancers, including gynecological cancers such as ovarian, cervical,and endometrial cancer.In this review, we summarize the contrasting regulatory roles of Sex-determining region Y box-containing genes in different gynecological cancers, as promotors with high expression levels or as suppressors with low expression levels.Expression levels of Sex-determining region Y box-containing genes were also identified as biomarkers of clinical features, including International Federation of Gynecology and Obstetrics stage, histopathologic grade together with disease-free survival, and treatment efficacy in patients with gynecological cancers.An understanding of the mechanisms whereby Sex-determining region Y box-containing genes regulate the progression of gynecological cancers will aid in the development of novel diagnostic and therapeutic strategies, while analysis of Sex-determining region Y box-containing expression levels will help to predict the prognosis of patients with gynecological cancers.

Fibrous gel polymer electrolyte for an ultrastable and highly safe flexible lithium-ion battery in a wide temperature range

Replacement of flammable liquid electrolytes with gel polymer electrolytes(GPEs)is a promising route to improve the safety of lithium-ion batteries(LIBs).However,polymer-based electrolytes have limited suitability at low/high temperatures due to the instability of the polymer at high temperatures and the low ionic conductivity of the gel state at low temperatures.Herein,an integrated design of electrodes/fibrous GPEs modified with graphene oxide(GO)is reported.Due to the integrated structure of electrodes/GPEs,the strong interface affinity between electrodes and GPEs ensures that the GPEs spun on electrodes do not shrink at high temperatures(160-180℃),thus preventing a short circuit of electrodes.Moreover,after GO modification,oxygen-containing functional groups of GO can accelerate Li^(+)transport of GO-GPEs even at a low temperature of−15℃.When these GPEs are applied to flexible LIBs,the LIBs show excellent electrochemical performance,with satisfactory cycling stability of 82.9%at 1 C after 1000 cycles at 25℃.More importantly,at a high temperature of 160℃,the LIBs can also discharge normally and light the green light-emitting diode.Furthermore,at a low temperature of−15℃,92.7%of its room-temperature capacity can be obtained due to the accelerated Li^(+)transport caused by GO modification,demonstrating the great potential of this electrolyte and integrated structure for practical gel polymer LIB applications.