Protective Effects of Common Masks against PM2.5

By using two PM2.5 automatic monitors,the protective effects of five common masks against PM2.5 were synchronously tested under actual ambient air conditions for a whole day. The results showed that not all masks had protective effects on PM2.5,and the protective effects of masks N95 and N90,which were designed specially for dust-proof,were superior among the five tested masks.

Uncontrolled hypertension in older patients： markers and associated factors to masked and white-coat effect

Background Hypertension is the main risk factor for cardiovascular diseases, affecting more than half the elderly population. It is essential to know if they have proper control of hypertension. The aim of this study was to identify the associated factors to masked uncon- trolled hypertension and false uncontrolled hypertension in older patients. Methods Two-hundred seventy-three individuals （70.1±6.7 years-old） had blood pressure （BP） measured at the office and by ambulatory BP monitoring （ABPM）, with the definition of controlled group （C）, individuals with high office BP and adequate ABPM, called white-coat effect group （WCE）, uncontrolled （UC）, and subjects with ap- propriate office BP and elevated ABPM denominated masked effect group （ME）. Age, body mass index, diabetes, pulse pressure （PP） and BP dipping during sleep were evaluated （Kruskal-Wallis test and logistic regression models）. Results Age was higher in UC than in C and ME （P 〈 0.01）, and 24-h ABPM PP was lower in C （48± 7 mmHg） and WCE （51±6 mmHg） than in UC （67±12 mmHg） and ME （59±8 mmHg） （P 〈 0.01）. Sleep systolic BP dipping was lower in ME than in C （P = 0.03）. Female gender was associated with a greater chance of being of ME group, which showed a higher PP and lower BP dipping during sleep. Conclusions In older individuals, office BP measure- ments did not allow the detection of associated factors that would permit to differentiate WCE from UC group and C from ME group. ABPM favored the identification of a higher PP and a lower BP dipping during sleep in the masked effect and uncontrolled groups.

Conductive Polymer Composites Fabricated by Disposable Face Masks and Multi-Walled Carbon Nanotubes: Crystalline Structure and Enhancement Effect

Influenced by recent COVID-19,wearing face masks to block the spread of the epidemic has become the simplest and most effective way.However,after the people wear masks,thousands of tons of medical waste by used dis-posable masks will be generated every day in the world,causing great pressure on the environment.Herein,con-ductive polymer composites are fabricated by simple melt blending of mask fragments(mask polypropylene,short for mPP)and multi-walled carbon nanotubes(MWNTs).MWNTs were used as modifiers for composites because of their high strength and high conductivity.The crystalline structure,mechanical,electrical and thermal enhancement effect of the composites were investigated.MWNTs with high thermal stability acted the role of promoting the crystallisation of mPP by expediting the crystalline nucleation,leading to the improvement of amount for crystalline nucleus.MWNTs fibers interpenetrate with each other in mPP matrix to form conducting network.With 2.0 wt% MWNTs loading,the tensile strength and electrical conductivity of the composites were increased by 809% and 7 orders of magnitude.MWNTs fibers interpenetrate with each other in mPP matrix to form conducting network.Thus,more conducting paths were constructed to transport carriers.The findings may open a way for high value utilization of the disposable masks.

Dependence of epoch-wise two-way nested ANOVA estimates of variances of unmodeled effects present in relative GPS positioning on satellite elevation cutoff angle and PDOP mask

Impact of satellite elevation cutoff angle and position dilution of precision(PDOP)mask change on epoch-wise variance components of unmodeled effects that accompany relative Global Positioning System(GPS)positioning is presented herein.Data used for this study refer to the winter and summer periods of the years with minimal(2008)and maximal(2013)solar activity.These data were collected every 30 s in static mode,at two permanent GPS stations located in Montenegro,establishing a mediumdistance(116-km-long)baseline with a height difference of approximately 760 m between its endpoints.The study showed that changing satellite elevation cutoff angle,with a fixed PDOP mask,affects epochwise two-way nested ANOVA estimates of variances related to the‘far-field’multipath(considered as the nested factor herein)and the combined unmodeled effect of tropospheric and ionospheric refraction(considered as the nesting factor herein).However,changing of PDOP mask,with a fixed satellite elevation cutoff angle,doesn’t affect epoch-wise two-way nested ANOVA estimate of variance of the combined unmodeled effect of tropospheric and ionospheric refraction,but,generally,affects the estimate of variance of the‘far-field’multipath(possibly mixed with a part of a‘shorter-term’ionospheric refraction),which is especially pronounced for the summer period.It should also be noted that there is a significant influence of satellite elevation cutoff angle change on both epoch-wise horizontal and vertical position accuracy,only for the summer period,especially in the presence of maximal solar activity,while there is no significant impact of PDOP mask change on epoch-wise positional accuracy.

灵活应用After Effects中的Mask制作视频动画

在商业视频动画项目中，很多时候客户给的制作时间并不是很充足，而对项目的要求却仍旧很高。面对这样的情况，有经验的设计师应该知道采用哪种风格和技巧能够快捷的制作出成熟的作品并令客户满意。熟知软件技巧、了解设计流行趋势应该是平日里要随时积累的基本功。在这次的教程中，我们有了另一个提高效率的法宝：便携式动力站HP Compap8510w，它的表现非常出色，完全能够满足视频动画（频道、视频包装）领域的实际工作需要。从事数字内容创作的你，相信也早想拥有一台高移动性工作站了吧。

反差一致性改进的MASK匀光算法

航空影像中存在的不均匀光照现象是遥感影像处理中要解决的一个重要问题。现有的MASK匀光处理技术能够在一定程度上解决这类问题。但是经过MASK匀光处理后的图像存在反差不均匀现象,即原始图像中较暗区域经过匀光后明显地表现出反差较低,而亮的区域则反差较大。针对此不足,提出了一种基于反差一致性改进的MASK匀光算法。实验证明,该方法能够迅速提高暗区域反差,抑制亮区域反差,达到整体影像的反差一致性,获得更好的匀光效果。

After Effects中常用键控技术分析及应用

After Effects是进行影视后期合成的一个重要软件.在分析键控在影视后期合成中的重要作用以及键控原理的基础上,以实例对After Effects中常用的键控技术进行了解析及应用,并比较了常用键控工具的各自优势.

After effect6.5中Vector paint原理及其特殊应用

After effect是一个适用于高端视频系统的专业型非线性编 辑创作系统。它提供了基于帧的视频设计途径。也为影视制作 人员提供了强大的影片编辑和制作工具。本文主要介绍After effect6.5中的新增功能——Vector paint的原理及其特殊的应用。

喉罩在胸腔镜下交感神经链切断术的应用效果

目的:探讨手汗症双侧胸腔镜下交感神经链切除术患者实施喉罩全身麻醉(以下简称全麻)和双腔气管插管全麻的临床效果。方法:回顾性分析2023年10月—2024年5月收治的40例单孔法完成手汗症病例的临床资料,随机分对照组和观察组,每组20例。对照组实行双腔气管插管全麻,观察组实行喉罩全麻。比较两组麻醉复苏时间、双侧手术总时间、术中出血量、术后视觉模拟疼痛评分(VAS)、住院时间和住院费用、术后并发症发生率及应激反应指标。结果:观察组麻醉复苏时间短于对照组(P<0.05);两组双侧手术总时间、术中出血量比较,差异无统计学意义(P>0.05);观察组术后1 d的VAS评分和白细胞计数(WBC)水平低于对照组,住院时间短于对照组,住院费用少于对照组(P<0.05);观察组术后咽痛、呛咳等发生率低于对照组(P<0.05);两组术后1 d的炎症因子水平较之前均呈升高趋势,但观察组白细胞介素-6(IL-6)、肿瘤坏死因子(TNF-α)、C反应蛋白(CRP)水平低于对照组(P<0.05);术后1 d观察组皮质醇(COR)、去甲肾上腺素(NE)水平均低于对照组(P<0.05)。结论:胸腔镜下交感神经链切断术中实施喉罩全麻,有效且安全,与双腔气管插管全麻相比,具有减轻术后疼痛、降低并发症风险、节约住院时间等突出优势。

General Anesthesia with Laryngeal Mask Airway: Etomidate VS Propofol for Hemodynamic Stability

Background: Propofol is the most popular induction agent for laryngeal mask airway (LMA) insertion in current anaesthesia practice however associated hypotension has been reported as its major disadvantage. Etomidate, which produces less hypotension, can be considered as an alternative agent for LMA insertion. Objectives: The objective of this study was to compare the hemodynamic effects of etomidate with propofol for induction of general anaesthesia (GA) for LMA. Ease of inserting LMA was also looked at. Material and Methods: It was a prospective randomized double blinded study. All ASA I and II patients of 15 - 60 years of age undergoing general anaesthesia with LMA for elective surgeries were included. Patients were induced with intravenous (I/V) fentanyl and induction agent either etomidate or propofol according to group randomization. LMA was inserted after 30 seconds. Intra-operative heart rate (HR), sys tolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), number of attempts and duration of LMA insertion were monitored. Results: There was no difference in the heart rate between the two groups. A significant drop was found for systolic blood pressure (SBP) in propofol group while diastolic blood pressure (DBP) was decreased in both the groups. In propofol group, successful insertion of LMA was achieved on the first attempt in 93.3% of patient as compared to 36.7% in etomidate group. Conclusion: Use of etomidate for induction of laryngeal mask anesthesia can prevent the hypotension following induction;however it may delay the insertion of laryngeal mask airway.

使用After Effects CC制作素描动画效果

影视艺术源自生活,高于生活,观众在这样的艺术中尽情享受,或有所愉悦,或有所感悟。故在影视后期包装制作过程中,常常需要实现将虚幻和现实结合起来的效果,如武侠世界或是静态的单调的影像逐渐丰满现实化等。本文中,笔者将介绍运用After Effects将素描状态转变为现实的视频效果的方法。

AE中Mask的特效运用——武侠片中的残影效果制作

After Effects是Adobe公司推出的运行于PC和MAC机上的专业级影视合成软件,也是目前最为流行的影视后期合成软件。我们经常在武侠片中看到的所谓的“残影”效果,就可以用After Effects做出来,下面我们就一起来看看这种令人惊讶的特技效果是怎么实现的。

Clinical Observation of Double Tube Laryngeal Mask in Fast-Track Anesthesia for Limb Orthopedic Surgery in Children with Cerebral Palsy

Objective: To compare and analyze the effect and safety of double tube laryngeal mask and endotracheal intubation general anesthesia in fast track anesthesia for limb orthopaedic surgery in children with cerebral palsy. Methods: 78 children with cerebral palsy undergoing limb orthopedic surgery were randomly divided into laryngeal mask group and intubation group, with 39 cases in each group. The perioperative hemodynamic indexes, anesthesia effect related indexes, anesthesia related complications or adverse reaction rates of the two groups were observed and compared between the two groups. Results: When the two groups of children entered the room, there was no significant difference in MAP and HR (P > 0.05);MAP and HR of children in the intubation group were higher than those in the laryngeal mask anesthesia group (P Conclusion: Laryngeal mask is used to establish the airway of intravenous general anesthesia in limb orthopaedic surgery of children with cerebral palsy, which is conducive to the stability of children’s circulatory and respiratory system, to reduce the impact of narcotic drugs on children, to reduce the incidence of postoperative anesthesia related complications, and to improve the anesthetic effect. It meets the requirements of fast track anesthesia, and can be widely used in clinical practice.

Clinical efficacy of mask continuous positive airway pressure mechanical ventilation in children with severe pneumonia

Objective: To investigate the clinical effects of the mask continuous positive airway pressure (CPAP) mechanical ventilation in children with severe pneumonia. Methods: A total of 100 cases of children with severe pneumonia were randomly divided into two groups, study group with 50 children and control group with 50 children. These 100 children were given comprehensive treatment measures: treatment of anti-infection, anti-respiratory failure, anti-heart failure (if necessary), relieving cough and reducing sputum, aerosol inhalation, limited fluid volume, nutrition support etc. Children in the study group were added mask continuous positive airway pressure mechanical ventilation (CPAP). Children in the control group were added ordinary mask oxygen inhalation. Investigated and checked the treatment effect in these two groups. Results: After treatment, SaO2, PaO2 in both two groups were showed significantly higher than before the treatment. PaO2 of the study group is obviously higher than the control group. The oxygen inhalation time of the study group was obviously lesser than the control group. The total effective rate of the study group was significantly higher than the control group which was 96.0% vs 66.0%. Conclusion: The mask continuous positive airway pressure (CPAP) mechanical ventilation can significantly improve the related symptoms and blood gas status of the children with severe pneumonia, shorten the oxygen inhalation time and had remarkable effect.

A Class of Chaotic Sequences with Gauss Probability Distribution for Radar Mask Jamming

A simple generation approach for chaotic sequences with Gauss probability distribution is proposed. Theoretical analysis and simulation based on Logistic chaotic model show that the approach is feasible and effective. The distribution characteristics of the novel chaotic sequence are comparable to that of the standard normal distribution. Its mean and variance can be changed to the desired values. The novel sequences have also good randomness. The applications for radar mask jamming are analyzed.

人口结构、科技创新与中国经济高质量发展——基于空间杜宾模型分析视角

人口要素和科技创新对实现经济高质量发展具有深度影响,人口要素与科技创新是经济增长的两大引擎。文中基于31个省、自治区、直辖市2008一2021年的面板数据,运用空间杜宾模型,从人口结构的4个维度出发,对人口结构、科技创新与经济高质量发展的关系进行了探析。研究结果表明:人口老龄化对本地和邻近地区均为显著的抑制性作用。人口城镇化与科技创新均对本地具有正向促进作用且对邻近地区为正向溢出效应。劳动供给对邻近地区促进作用更为显著,而人力资本未达到预期促进作用。此外,科技创新未能弥补老龄化对经济高质量发展的抑制作用且存在部分遮掩效应。因此,仍需加强区域合作与整合,把握好老龄人口机遇,充分挖掘老龄人力资源,有效推进人口城镇化,加大研发投入强度,促进科技创新,将推动经济高质量发展。

人口流动背景下黄河流域碳减排路径研究

绿色低碳对黄河流域生态保护和高质量发展意义重大,从人口角度入手,以2006-2020年黄河流域60个地级市为研究对象,通过构建固定效应模型分析人口流动与碳排放之间的关系,采用中介效应模型与调节效应模型对人口流动背景下黄河流域的碳减排路径进行探讨。研究结果表明:人口流动对流域碳排放的影响呈先抑制后促进的“U形”关系;人力资本积累是黄河流域的重要碳减排路径;金融发展水平、交通及文化基础设施建设水平的提高具有减排调节效应。据此提出黄河流域碳减排路径相关的对策建议。

生育性别偏好如何影响育龄女性的生育意愿?——基于社会经济地位的遮掩效应

在逐渐宽松的生育政策背景下,生育性别偏好会对育龄女性生育意愿产生影响。本文基于CFPS2018数据,采用泊松回归和Bootstrap方法,探讨了生育性别偏好、社会经济地位与育龄女性生育意愿三者之间的关系,并分析了生育性别偏好对不同群体女性生育意愿的空间异质性影响。研究发现:不同生育性别偏好对女性生育意愿的影响方向和强度不同。相较于无性别偏好,男孩偏好整体上对育龄女性生育意愿表现出显著的负向抑制作用,然而该抑制作用在东部和西部农村地区不显著;儿女双全偏好整体上表现出显著的正向促进作用,且在东部城镇地区促进作用更大;女孩偏好整体上对女性生育意愿影响不显著,然而在东部城镇地区表现出对生育意愿显著的抑制作用,而在西部农村地区发挥着显著正向促进作用。此外,社会经济地位在性别偏好和生育意愿之间发挥了遮掩效应,受教育水平的提升会弱化男孩偏好对生育意愿的抑制作用,收入水平的提高会削弱女孩偏好对生育意愿的促进作用。在当前生育率持续走低的严峻形势下,建议充分尊重女性生育自主权,并且实施区域差异化的生育支持措施以提高女性生育意愿。

标准参与、产业链协同与企业高质量发展——基于中国高端装备制造企业的实证分析

在外部环境高度不确定的背景下,中国企业正面临技术和市场资源双重空间挤压的难题,实现高质量发展是破局的关键。技术标准作为技术公共化的载体,具有很强的资源扩展属性,但其在企业高质量发展过程中发挥怎样的作用以及中间机制还不明晰。本文以2008~2022年362家上市高端装备制造企业为研究样本,实证分析标准参与对企业高质量发展的影响,以及产业链协同在其中的作用机制。结果表明:标准参与对产业链协同和企业高质量发展均具有正向影响,产业链协同在标准参与和高质量发展中存在遮掩效应。进一步研究发现,国有、西部地区以及中美贸易摩擦前企业的标准参与更有助于实现高质量发展。本文的研究发现为企业的高质量发展提供了有益思路,也为政府制定规范性和产业性政策提供了一定的参考。

煤中原生活性位点的水−气掩蔽效应及脱附后煤体的常温氧化

煤的常温氧化为煤炭自燃提供初始热量来源,探究煤中可与氧气常温条件下发生氧化反应的原生活性物质是煤自燃理论研究的难题。此前进行的受热分解实验发现,热解煤中含有能在惰性气体中稳定存在并与氧气发生常温氧化的活性位点,因此推测煤中同样可能存在惰性介质下被迫封存的原生活性位点。为进行煤中原生活性位点的探寻,运用真空干燥技术,使原煤中能够在高负压的低温环境下完成水分的蒸发和气体的脱除。同时借助循环氧化在线监测技术,设计实施不同因素(煤种、脱附温度、氧化温度、粒径)条件下脱附后煤样的常温氧化实验,并结合相应的低温氮吸附、XPS、ESR实验分析反应机理。循环条件下的常温氧化实验表明,真空脱附后的煤体在常温氧化过程中会形成大量的CO和CO_(2)等气体氧化产物,且气体在通入氧气后很快出现并不断积累,证明煤在常温下即可发生氧化反应。原生煤体脱附后的常温氧化实验说明原始煤体中存在大量受水−气掩蔽影响的活性位点,而负压脱附水分和气体后会导致活性位点的大量暴露并形成有利于氧气输运和反应的通道,从而迅速发生氧化反应。因此实验找到了导致原生煤体自发氧化的活性结构,实验将活性位点的常温氧化观点从受热分解的特殊状态扩展到一般状态。由气体产物生成规律对比可知,不易被孔隙吸附的CO会在原生活性位点与氧气接触瞬间迅速产生,据此得到CO相较于CO_(2)而言更适合作为活性位点浓度的直观气体评价指标。煤体原生活性位点的常温氧化有助于煤炭自燃机理的揭示,为高瓦斯矿井瓦斯抽采自燃及低阶煤井下CO超限问题提供解决思路。