Tapered dielectric structure in metal as a wavelength-selective surface plasmon polariton focuser

Symmetric tapered dielectric structures in metal have demonstrated applications such as the nanofocusing of surface plasmon polaritons, as well as the waveguiding of V-channel polaritons. Yet the fabrication of smooth-surfaced tapered structure remains an obstacle to most researchers. We have successfully developed a handy method to fabricate metal-sandwiched tapered nanostructures simply with electron beam lithography. Though these structures are slightly different from conventional symmetric V-shaped structures, systematic simulations show that similar functionality of surface plasmon polariton nanofocusing can still be achieved. When parameters are properly selected, wavelength- selective nanofocusing of surface plasmon polaritons can be obtained.

Progress of research in the application of ultrasound technology for the treatment of Alzheimer’s disease

Alzheimer’s disease is a common neurodegenerative disorder defined by decreased reasoning abilities,memory loss,and cognitive deterioration.The presence of the blood-brain barrier presents a major obstacle to the development of effective drug therapies for Alzheimer’s disease.The use of ultrasound as a novel physical modulation approach has garnered widespread attention in recent years.As a safe and feasible therapeutic and drug-delivery method,ultrasound has shown promise in improving cognitive deficits.This article provides a summary of the application of ultrasound technology for treating Alzheimer’s disease over the past 5 years,including standalone ultrasound treatment,ultrasound combined with microbubbles or drug therapy,and magnetic resonance imaging-guided focused ultrasound therapy.Emphasis is placed on the benefits of introducing these treatment methods and their potential mechanisms.We found that several ultrasound methods can open the blood-brain barrier and effectively alleviate amyloid-βplaque deposition.We believe that ultrasound is an effective therapy for Alzheimer’s disease,and this review provides a theoretical basis for future ultrasound treatment methods.

FOCUS-PDCA在降低在新生儿院内尿布性皮炎发生率的应用研究

探讨FOCUS -PDCA在新生儿院内尿布性皮炎管理的应用效果。方法 选取2023年6月1日至2023年9月30日入住新生儿患儿 379例,按入院时间先后顺序分为对照组(2023年6月1号-2023年7月31号)和试验组(2023年8月1号-2023年9月31号)。对照组采取常规护理方案,试验组采取运用FOCUS -PDCA进行修订相关流程、护理常规、开展针对性培训、加强督查与干预等循环管理。比较2组新生儿院内尿布性皮炎发生率。结果 试验组院内尿布性皮炎发生率为9.2‰,低于对照组的25.2 ‰(χ2=4.410578,P<0.05);且2023年8月、9月新生儿院内尿布性皮炎的发生率分别为15.8‰、11.8‰,整体呈一个下降的趋势。结论 采用FOCUS -PDCA进行循环管理,实施培训、督查与干预用于新生儿住院患者管理,可降低其院内尿布性皮炎的发生率。

多花黄精对少弱精子症大鼠生精细胞凋亡的保护作用及药效物质基础研究

目的阐明多花黄精对少弱精子症大鼠模型生精细胞凋亡的保护作用及药效物质基础。方法采用UHPLC-Q Exactive Focus HRMS技术鉴定多花黄精化学成分,及其提取物灌胃给予大鼠后在血清和睾丸组织中的化学成分。设置空白组、模型组、阳性药组(左卡尼汀300 mg/kg)及多花黄精高、中、低剂量组(10、5和2.5 g/kg),考察其改善少弱精子症的药理作用,每组6只大鼠。通过HE染色观察大鼠睾丸组织病理形态,TUNEL染色观察大鼠睾丸生精细胞的凋亡情况,免疫荧光法检测DNMT3A和PIWIL1蛋白表达。结果从多花黄精提取物、大鼠血清、大鼠睾丸中分别鉴定出138种、23种、30种化学成分。模型组大鼠睾丸曲细精管中大量生精细胞凋亡,DNMT3A和PIWIL1蛋白低表达,而多花黄精高、中剂量组大鼠睾丸曲细精管中TUNEL阳性生精细胞数量减少,DNMT3A和PIWIL1蛋白表达显著升高。结论多花黄精对少弱精子症大鼠具有保护作用,其可能是通过上调大鼠睾丸中DNMT3A和PIWIL1的表达,逆转生精细胞的凋亡。

蛭蛇通络胶囊的入血、入脑成分研究

目的分析蛭蛇通络胶囊入血、入脑成分。方法16只大鼠随机分为4组,灌胃给药(3.1 g/kg),建立脑缺血再灌注损伤(MACO)模型,取血和脑组织,UHPLC-Q Exactive Focus MS/MS法鉴定原型成分。结果共鉴定出70种成分,血浆中有20种,主要为黄酮类、丹参醌类、川芎苯酞类,7种能透过血脑屏障进入脑组织。与正常给药组比较,MACO给药组入血成分增加间羟基苯甲酸、毛蕊异黄酮苷、莪术烯醇、洋川芎内酯B、二氢丹参酮Ⅰ、隐丹参酮;左脑组织(梗死侧)入脑成分减少葛根素、榄香素、新蛇床内酯,增加丹酚酸A、洋川芎内酯I、二氢丹参酮Ⅰ。结论蛭蛇通络胶囊入血、入脑成分及脑缺血再灌注损伤大鼠体内增强吸收的苯酞类、醌类、酚类成分可能是治疗脑梗塞的活性物质。

参仙升脉口服液化学成分的UHPLC-Q Exactive Focus MS/MS快速分析

目的探究参仙升脉口服液的化学物质基础。方法利用超高效液相色谱-四极杆/静电场轨道阱高分辨质谱(UHPLC-Q Exactive Focus MS/MS)对参仙升脉口服液的化学成分进行整体、系统辨识。采用Thermo Accucore aQ C_(18)色谱柱(150 mm×2.1 mm,2.6μm),流动相0.1%甲酸水溶液(A)-甲醇(B)梯度洗脱,洗脱程序为0-13 min,5%-60%B;13-27 min,60%-95%B;27-30 min,95%B,流速0.3 mL·min^(-1),柱温30°C;质谱分析离子化方式为加热电喷雾离子化(H-ESI),扫描模式为正、负离子切换,扫描范围m/z 120-1800,碰撞能量30 eV、50 eV、70 eV。结果共鉴定出160个化学成分,包括29个黄酮类成分,24个有机酸类成分,21个生物碱类成分,19个萜类成分,15个苯丙素类成分,12个皂苷类成分和40个其他类成分;其中6个化学成分(芦丁、补骨脂苷、异补骨脂苷、补骨脂素、异补骨脂素和补骨脂酚)经对照品比对确认。结论该研究借助UHPLC-Q Exactive Focus MS/MS技术实现了参仙升脉口服液化学成分准确、快速、系统的分析和鉴定,为其化学物质基础的阐明和质量控制提供了重要依据。

Properties of focused Laguerre–Gaussian beam propagating in anisotropic ocean turbulence

We analyze the properties of a focused Laguerre–Gaussian(LG)beam propagating through anisotropic ocean turbulence based on the Huygens–Fresnel principle.Under the Rytov approximation theory,we derive the analytical formula of the channel capacity of the focused LG beam in the anisotropic ocean turbulence,and analyze the relationship between the capacity and the light source parameters as well as the turbulent ocean parameters.It is found that the focusing mirror can greatly enhance the channel capacity of the system at the geometric focal plane in oceanic turbulence.The results also demonstrate that the communication link can obtain high channel capacity by adopting longer beam wavelength,greater initial beam waist radius,and larger number of transmission channels.Further,the capacity of the system increases with the decrease of the mean squared temperature dissipation rate,temperature-salinity contribution ratio and turbulence outer scale factor,and with the increase of the kinetic energy dissipation rate per unit mass of fluid,turbulence inner scale factor and anisotropy factor.Compared to a Hankel–Bessel beam with diffraction-free characteristics and unfocused LG beam,the focused LG beam shows superior anti-turbulence interference properties,which provide a theoretical reference for research and development of underwater optical communication links using focused LG beams.

Co-doped BaFe_(2)As_(2) Josephson junction fabricated with a focused helium ion beam

Josephson junction plays a key role not only in studying the basic physics of unconventional iron-based superconductors but also in realizing practical application of thin-film based devices,therefore the preparation of high-quality iron pnictide Josephson junctions is of great importance.In this work,we have successfully fabricated Josephson junctions from Co-doped BaFe_(2)As_(2)thin films using a direct junction fabrication technique which utilizes high energy focused helium ion beam(FHIB).The electrical transport properties were investigated for junctions fabricated with various He^(+)irradiation doses.The junctions show sharp superconducting transition around 24 K with a narrow transition width of 2.5 K,and a dose correlated foot-structure resistance which corresponds to the effective tuning of junction properties by He^(+)irradiation.Significant J_c suppression by more than two orders of magnitude can be achieved by increasing the He^(+)irradiation dose,which is advantageous for the realization of low noise ion pnictide thin film devices.Clear Shapiro steps are observed under 10 GHz microwave irradiation.The above results demonstrate the successful fabrication of high quality and controllable Co-doped BaFe_(2)As_(2)Josephson junction with high reproducibility using the FHIB technique,laying the foundation for future investigating the mechanism of iron-based superconductors,and also the further implementation in various superconducting electronic devices.

FOCUS-PDCA模式对老年肌少症病人日常生活能力和生活质量影响的Meta分析

目的:系统评价FOCUS-PDCA模式对老年肌少症病人日常生活能力和生活质量的影响。方法:检索PubMed、Web of Science、the Cochrane Library、中国知网、万方数据库、维普数据库、中国生物医学文献数据库中关于FOCUS-PDCA模式对老年肌少症病人日常生活能力和生活质量影响的随机对照试验,检索时限从建库至2022年12月31日。采用RevMan 5.4软件进行Meta分析。结果:共纳入5篇文献,涉及534例病人。Meta分析结果显示,使用FOCUS-PDCA模式干预可有效改善病人的生活质量[SMD=2.52,95%CI(1.50,3.54),P<0.000 01],提高日常活动能力[MD=23.94,95%CI(14.96,32.96),P<0.000 01]。结论:现有证据表明,FOCUS-PDCA模式可提高老年肌少症病人的日常生活能力,改善其生活质量。

基于聚焦变换解卷积的宽带稳健波束形成

In the field of array signal processing,uniform linear arrays(ULAs)are widely used to detect/separate a weak target and estimate its direction of arrival from interference and noise.Conventional beamforming(CBF)is robust but restricted by a wide mainlobe and high sidelobe level.Covariance-matrix-inversed beamforming techniques,such as the minimum variance distortionless response and multiple signal classification,are sensitive to signal mismatch and data snapshots and exhibit high-resolution performance because of the narrow mainlobe and low sidelobe level.Therefore,compared with the wideband CBF,this study proposes a robust focused-and-deconvolved conventional beamforming(RFD-CBF),utilizing the Richardson–Lucy(R-L)iterative algorithm to deconvolve the focused conventional beam power of a half-wavelength spaced ULA.Then,the focused-and-deconvolved beam power achieves a narrower mainlobe and lower sidelobe level while retaining the robustness of wideband CBF.Moreover,compared with the wideband CBF,RFD-CBF can obtain a higher output signal-to-noise ratio(SNR).Finally,the performance of RFD-CBF is evaluated through numerical simulation and verified by sea trial data processing.

Focusing on the tetra-partite synapse in Parkinson’s disease research using human patient-derived neurons

Parkinson’s disease(PD)was first described as a neurological disease by Dr.James Parkinson in 1817 as a“shaking palsy”.Since that time,much more is known about the pathophysiology of PD yet the disease is still uncurable.The hallmark of the disease is often considered Lewy body neural inclusions in the substantia nigra pars compacta and other brain areas,although not all patients have these inclusions.The patients exhibit massive neuronal cell loss in the substantia nigra pars compacta,which is associated with the motor symptoms of tremor,bradykinesia,rigidity,and postural instability.PD is the second most common neurodegenerative disease after Alzheimer’s disease with a prevalence of around 1%of individuals over the age of 60.

结合FOCUS模式的PDCA护理干预在多发性骨髓瘤患者中的应用分析

分析结合FOCUS模式的PDCA护理干预在多发性骨髓瘤患者中的应用。方法 选择2022年6月-2024年1月我院收治110例患者。随机分组。对照组采用PDCA护理干预。观察组采用结合FOCUS模式的PDCA护理干预。结果 观察组知识水平(病因、控制、预防、用药)、APTT、自我效能、满意度高于对照组,P<0.05。Fbg、D-D、PT、SAS、SDS、神经病变低于对照组,P<0.05。结论 结合FOCUS模式的PDCA护理干预能够改善多发性骨髓瘤患者的知识水平和凝血指标,提高患者自我效能和满意度,缓解负面心理状态和神经病变进度。

Highly Efficient Broadband Achromatic Microlens Design Based on Low-Dispersion Materials

Metalenses with achromatic performance offer a new opportunity for high-quality imaging with an ultracompact configuration;however,they suffer from complex fabrication processes and low focusing efficiency.In this study,we propose an efficient design method for achromatic microlenses on a wavelength scale using materials with low dispersion,an adequately designed convex surface,and a thickness profile distribution.By taking into account the absolute chromatic aberration,relative focal length shift(FLS),and numerical aperture(NA),microlens with a certain focal length can be realized through our realized map of geometric features.Accordingly,the designed achromatic microlenses with low-dispersion fused silica were fabricated using a focused ion beam,and precise surface profiles were obtained.The fabricated microlenses exhibited a high average focusing efficiency of 65%at visible wavelengths of 410-680 nm and excellent achromatic capability via white light imaging.Moreover,the design exhibited the advantages of being polarization-insensitive and near-diffraction-limited.These results demonstrate the effectiveness of our proposed achromatic microlens design approach,which expands the prospects of miniaturized optics such as virtual and augmented reality,ultracompact microscopes,and biological endoscopy.

The W transform and its improved methods for time-frequency analysis of seismic data

The conventional linear time-frequency analysis method cannot achieve high resolution and energy focusing in the time and frequency dimensions at the same time,especially in the low frequency region.In order to improve the resolution of the linear time-frequency analysis method in the low-frequency region,we have proposed a W transform method,in which the instantaneous frequency is introduced as a parameter into the linear transformation,and the analysis time window is constructed which matches the instantaneous frequency of the seismic data.In this paper,the W transform method is compared with the Wigner-Ville distribution(WVD),a typical nonlinear time-frequency analysis method.The WVD method that shows the energy distribution in the time-frequency domain clearly indicates the gravitational center of time and the gravitational center of frequency of a wavelet,while the time-frequency spectrum of the W transform also has a clear gravitational center of energy focusing,because the instantaneous frequency corresponding to any time position is introduced as the transformation parameter.Therefore,the W transform can be benchmarked directly by the WVD method.We summarize the development of the W transform and three improved methods in recent years,and elaborate on the evolution of the standard W transform,the chirp-modulated W transform,the fractional-order W transform,and the linear canonical W transform.Through three application examples of W transform in fluvial sand body identification and reservoir prediction,it is verified that W transform can improve the resolution and energy focusing of time-frequency spectra.

Simulating the evolution of focused waves by a two-layer Boussinesq-type model

Accurate simulation of the evolution of freak waves by the wave phase focusing method requires accurate linear and nonlinear properties,especially in deep-water conditions.In this paper,we analyze the ability to simulate deep-water focused waves of a two-layer Boussinesq-type(BT)model,which has been shown to have excellent linear and nonlinear performance.To further improve the numerical accuracy and stability,the internal wavegenerated method is introduced into the two-layer Boussinesq-type model.Firstly,the sensitivity of the numerical results to the grid resolution is analyzed to verify the convergence of the model;secondly,the focused wave propagating in two opposite directions is simulated to prove the symmetry of the numerical results and the feasibility of the internal wave-generated method;thirdly,the limiting focused wave condition is simulated to compare and analyze the wave surface and the horizontal velocity of the profile at the focusing position,which is in good agreement with the measured values.Meanwhile the simulation of focused waves in very deep waters agrees well with the measured values,which further demonstrates the capability of the two-layer BT model in simulating focused waves in deep waters.

aBIOTECH征稿通知

Focused Issue on Epigenetic Regulation and Its potential Applications in Crop Improvement Honorary Editor Hao Yu National University of Singapore Guest Editors:Cheng-Guo Duan Shanghai Center for Plant Stress Biology/Center of Excellence in Molecular Plant Sciences,CAS Silin Zhong The Chinese University of Hong Kong Issue Scope/Topics:The journal of a BIOTECH is pleased to announce that it will publish a special issue on“Epigenetic regulation and its applications in crop improvement”.

Magnetic resonance-guided focused ultrasound for essential tremor:a prospective,single center,single-arm study

The safety and effectiveness of magnetic resonance-guided focused ultrasound thalamotomy has been broadly established and validated for the treatment of essential tremor.In 2018,the first magnetic resonance-guided focused ultrasound system in Chinese mainland was installed at the First Medical Center of the PLA General Hospital.This prospective,single center,open-label,single-arm study was part of a worldwide prospective multicenter clinical trial(ClinicalTrials.gov Identifier:NCT03253991)conducted to confirm the safety and efficacy of magnetic resonance-guided focused ultrasound for treating essential tremor in the local population.From 2019 to 2020,10 patients with medication refractory essential tremor were recruited into this open-label,single arm study.The treatment efficacy was determined using the Clinical Rating Scale for Tremor.Safety was evaluated according to the incidence and severity of adverse events.All of the subjects underwent a unilateral thalamotomy targeting the ventral intermediate nucleus.At the baseline assessment,the estimated marginal mean of the Clinical Rating Scale for Tremor total score was 58.3±3.6,and this improved after treatment to 23.1±6.4 at a 12-month follow-up assessment.A total of 50 adverse events were recorded,and 2 were defined as serious.The most common intraoperative adverse events were nausea and headache.The most frequent postoperative adverse events were paresthesia and equilibrium disorder.Most of the adverse events were mild and usually disappeared within a few days.Our findings suggest that magnetic resonance-guided focused ultrasound for the treatment of essential tremor is effective,with a good safety profile,for patients in Chinese mainland.

Half-integer Shapiro steps in MgB_(2) focused He ion beam Josephson junctions

Half-integer microwave induced steps(Shapiro steps)have been observed in many different Josephson junction systems,which have attracted a lot of attention because they signify the deviation of current phase relation(CPR)and uncover many unconventional physical properties.In this article,we first report the discovery of half-integer Shapiro steps in MgB_(2)focused He ion beam(He-FIB)Josephson junctions.The half-integer steps'dependence on microwave frequency,temperature,microwave power,and magnetic field is also analyzed.We find that the existence of half-integer steps can be controlled by the magnetic field periodically,which is similar to that of high temperature superconductor(HTS)grain boundary junctions,and the similarity of the microstructures between gain boundary junctions and He-FIB junctions is discussed.As a consequence,we mainly attribute the physical origin of half-integer steps in MgB_(2)He-FIB junctions to the model that a He-FIB junction is analogous to a parallel junctions'array.Our results show that He-FIB technology is a promising platform for researching CPR in junctions made of different superconductors.

Focus on pet diseases

Pets become vital companions in human life.Tey ofer companionship and emotional support,and contribute signifcantly to physical and mental health,as well as social activities.Living with pets can stimulate human bodies to release more“afnity hormones”such as serotonin,dopamine,and oxytocin,which helps alleviate negative emotions.Te human-animal bond can enhance the human body’s ability to eliminate toxins,reduce the risk of illnesses,strengthen the immune system,and alleviate depressive symptoms.Moreover,pet-related social activities can facilitate the making of new friends and the establishment of social connections,serving as a bridge for those who struggle with social interactions.

Research on Improved MobileViT Image Tamper Localization Model

As image manipulation technology advances rapidly,the malicious use of image tampering has alarmingly escalated,posing a significant threat to social stability.In the realm of image tampering localization,accurately localizing limited samples,multiple types,and various sizes of regions remains a multitude of challenges.These issues impede the model’s universality and generalization capability and detrimentally affect its performance.To tackle these issues,we propose FL-MobileViT-an improved MobileViT model devised for image tampering localization.Our proposed model utilizes a dual-stream architecture that independently processes the RGB and noise domain,and captures richer traces of tampering through dual-stream integration.Meanwhile,the model incorporating the Focused Linear Attention mechanism within the lightweight network(MobileViT).This substitution significantly diminishes computational complexity and resolves homogeneity problems associated with traditional Transformer attention mechanisms,enhancing feature extraction diversity and improving the model’s localization performance.To comprehensively fuse the generated results from both feature extractors,we introduce the ASPP architecture for multi-scale feature fusion.This facilitates a more precise localization of tampered regions of various sizes.Furthermore,to bolster the model’s generalization ability,we adopt a contrastive learning method and devise a joint optimization training strategy that leverages fused features and captures the disparities in feature distribution in tampered images.This strategy enables the learning of contrastive loss at various stages of the feature extractor and employs it as an additional constraint condition in conjunction with cross-entropy loss.As a result,overfitting issues are effectively alleviated,and the differentiation between tampered and untampered regions is enhanced.Experimental evaluations on five benchmark datasets(IMD-20,CASIA,NIST-16,Columbia and Coverage)validate the effectiveness of our proposed model.The meticulously calibrated FL-MobileViT model consistently outperforms numerous existing general models regarding localization accuracy across diverse datasets,demonstrating superior adaptability.