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ROADM（可重构的光分插复用器）是构建大型全光交换网络的核心设备。目前,大部分商用ROADM支持无色和无向性,但无阻塞性由于其高成本仍无法广泛应用,因此有效降低光通信业务的阻塞率是当前亟待解决的问题。文章基于具有多个上下路端口模块的有阻塞ROADM节点架构,提出了三种RWA（路由和波长分配）算法,以有效提高光通道业务的阻塞性能。仿真结果表明,结合上下路端口状态的波平面算法能有效地降低光通道业务的阻塞率。

光纤偏振复用系统中两束偏振态相互正交的光在一根光纤中传输时,由于偏振模色散和偏振耦合等因素,会产生串扰。文章针对这一问题,将基于互信息最小化的ICA（独立分量分析）算法应用到光纤通信偏振复用系统输出信号的分离中。仿真结果表明,采用该方法在无需任何先验知识的情况下,可以很好地分离出原始信号。

Objective To explore the influencing factors and current situation about frailty of the elderly patients in Beijing, and to provide references for further health assessment about elderly patients, in order to provide reference about choosing the right methods for nursing elderly patients and improving the quality of nursing. Methods The convenience sampling method was used to select the elderly inpatients admitted to three hospitals in Beijing from April to May 2021. Use the Tilburg frailty indicator (TFI) to investigate and assess the 200 elderly patients. Results The score of frailty in elderly patients is (5. 34±2. 99), about 57. 99%(98/169) elderly patients were living with frailty. Lower scores of the project was “Questions related to living alone”(13. 02%), “Cognition”(13. 02%) and “Coping” (18. 93%); Higher scores of the project was “Physical health”(68. 05%), “difficulty in walking”(55. 03%) and “Physical tiredness”(49. 70%). The elderly patients’ “age”, “presence of two or more chronic diseases”, “life events in the last year” were related to frailty(P＜0. 05). Conclusion In hospitals of Beijing, the frailty conditions are more common in elderly patients. It should be highly concerned about the elderly patients in nursing working, in order to provide nursing skills systematically and reasonably, make them adapted to the life in hospital. (目的 了解北京老年住院患者的衰弱状况, 分析其相关因素, 为老年住院患者的健康评估提供临床依据, 并为选择适合衰弱老年住院患者的护理保健方法、提高护理质量提供方向。方法 采用方便抽样法选取北京市3所三级甲等综合医院2021年4月—5月收治例老年住院患者, 采用Tilburg衰弱指数(TFI)评估量表对其进行调查评估。结果 老年住院患者衰弱指数总得分为(5. 34±2. 99)分, 衰弱人群约占57. 99%(98/169)。得分率较低的项目为“独居问题”(13. 02%)、“认知情况”(13. 02%)和“应对能力”(18. 93%); 得分率较高的项目为“身体健康状况”(68. 05%)、“行走困难”(55. 03%)和“疲劳感”(49. 70%)。其中, 衰弱程度与老年住院患者的“年龄”、“是否患有两种或两种以上慢性疾病”和“在过去的一年的生活事件”相关(P＜0. 05)。结论 在北京市三级甲等综合医院中, 老年住院患者衰弱情况发生率较高, 在护理工作中, 应高度关注老年住院患者, 为其提供科学合理的护理服务, 使其较好的适应住院生活。)

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In fractured tight gas reservoirs, hydraulically induced fractures are usually simplified into straight-shaped fractures for predicting productivity of horizontal wells. Whereas, actual fractures are so complex that accurate prediction productivity becomes challenging work. In this case, considering tree-shaped fractures better fitting with actual fractures and gas slippage effect, a new productivity model was proposed for fractured horizontal well and the contributing factors was examined to productivity. The results demonstrate that in comparison with the straight-shaped fracture, the present model in terms of the tree-shaped fracture predicts higher productivity which is positively associated with its length ratio and branching level whereas negatively correlated with its branching angle and almost unaffected by its width ratio. Furthermore, well productivity decreases with the Knudsen number and boundary radius of reservoir, whereas increases with the fracture spacing and length and is almost unaffected by the fracture permeability. Fracture productivity is positively associated with its spacing and unrelated to its permeability. While, increasing fracture length can increase fracture productivity in the toe and foot ends of horizontal well whereas decrease fracture productivity in the center. These findings contributes to design and development of horizontal wells in tight gas reservoirs. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Fudan University Journal of Medical Sciences is the property of Fudan University Journal of Medical Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

China has abundant straw resources, however, most of them have not been effectively developed and utilised, resulting in a waste of resources. Therefore, the development of straw puffing technology and its efficient use has become an unavoidable trend. This paper firstly intro- duces the main components of crop straw, then gives an in-depth overview of the working principle of screw extruder, details the research history of single-screw, twin-screw and three-screw extruders in the field of straw extrusion, and analyses the advantages and disadvantages of various types of extruders. At the same time, a comprehensive summary of the influencing factors in the expansion process is also presented. Based on the application of straw bulking, the article looks forward to the utilisation of straw in pulping, composite boards and ethanol, providing theoretical guidance for the efficient utilisation of straw. [ABSTRACT FROM AUTHOR]

The construction of ecological civilization and the realization of common prosperity are two major development strategies in China. In the context of ecological civilization construction, it is essential to achieve common prosperity through reforming the natural resource assets property rights system. This article qualitatively analyzes the functions of the natural resource assets property rights system by adopting the methods of functional analysis and interdisciplinary analysis and empirically analyzes its associated logic with the common prosperity by using the case analysis method. The results indicate that: ① There are four basic functions (marketization, capitalization, resource allocation, and ecologicalization) in the natural resource assets property rights system. ② In the process of utilizing natural resources to achieve common prosperity, the marketization function of the natural resource assets property rights system can transform natural resources into natural assets; the capitalization function can transform natural assets into natural capital; the resource allocation function can optimize the allocation of natural resources; and the ecologicalization function can preserve and increase the value of natural resources, thus achieving a win-win situation between ecological civilization construction and common prosperity. ③ Common prosperity cannot be achieved alone by utilizing natural resources; the achievement of common prosperity by utilizing natural resources is actually the result of the reform of the natural resources system and the property rights system. The policy implications of this study include: ① In terms of perfecting the property rights system, China's natural resource assets property rights system should be improved in the context of total factor productivity. ② In dealing with the relationship between the government and the market, we should make scientific distinctions between market allocation and government guidance according to different types of resource classification, making the market play a decisive role in resource allocation. ③ In maintaining the order of market transactions, the Civil Code should be used to protect the transactions of natural resource assets property rights. [ABSTRACT FROM AUTHOR]

BACKGROUND: Graphene is the thinnest, strongest, and toughest type of two-dimensional new crystal material, demonstrating significant advantages in biomedical applications. Angiogenesis and vascularization of bone are key factors in tissue repair and regeneration, and are effective ways to address vascular and osteogenic issues. OBJECTIVE: To review the characteristics and mechanisms of graphene and its derivatives in promoting angiogenesis activity and vascularizing bone, in order to provide a reference for their clinical application in vascular tissue repair and regeneration. METHODS: Using a computer to search for relevant literature included in PubMed, ScienceDirect, CNKI, and Wanfang databases, the Chinese search terms were “grapheme”, “angiogenesis, vascularization”, “vascularized bone”, and “endothelial cells”, while the English search terms were “graphene” “angiogenesis OR vascularization” “vascularized bone” “endothelial cells”. After excluding literature unrelated to the topic of the article, according to the inclusion and exclusion criteria, 62 articles were ultimately included for result analysis. RESULTS AND CONCLUSION: (1) At present, graphene oxide has been studied more and is the most widely used in graphene and its derivatives. (2) Graphene and its derivatives are suitable for heart, bone, nerve, and wound healing related diseases. (3) Graphene and its derivatives have excellent physical and chemical properties and biological properties, but they have potential cytotoxicity. We should pay attention to its biological safety in application. (4) The application of graphene and its derivatives requires further research to demonstrate the optimal size and concentration and measures to reduce toxicity. (5) On the cellular level, graphene and its derivatives can promote angiogenic activity by tip endothelial cell phenotype, mesenchymal stem cell adhesion and proliferation, and vascular smooth muscle cell growth. (6) On the molecular level, graphene and its derivatives can increase the expression of vascular endothelial growth factor, basic fibroblast growth factor, hepatocyte growth factor and activate reactive oxygen species/nitric oxide synthase/nitric oxide signaling pathway, lysophosphatilate R6/Hippo-YAP pathway, stromal cell-derived factor-1/vascular endothelial growth factor and ZEB 1/Notch1 pathway. (7) Grapheme oxide and graphene oxide-copper phosphorylated extracellular regulatory protein kinase and activated hypoxia-inducible factor-1, thereby promoting the up-regulation of vascular endothelial growth factor and bone morphogenetic protein-2 expression, and promoting angiogenesis and vascularized bone. (8) In summary, graphene and its derivatives, especially graphene oxide, have great application prospects in the repair and regeneration of vascularized tissues due to their excellent biological properties, good angiogenesis and vascularized bone ability. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of sodium hydrosulfide (NaHS) on renal ischemia-reperfusion (I/R) injury in rats, and the relationship between its mechanism and Klotho protein. Methods We selected 18 male SD rats and randomly divided them into the sham group, I/R group, and NaHS intervention group (I/R + NaHS group), with 6 rats in each group. In the I/R group, we removed the right kidney, and then used non-invasive arterial clips to clamp the left renal pedicle to simulate the state of acute renal ischemia, and released the arterial clip after 45 minutes of clamping to simulate the state of renal reperfusion. After the acute renal ischemia model was established in the NaHS intervention group, NaHS was injected into the left renal artery, followed by reperfusion. The sham operation group was not clamped. After 24 h of reperfusion, blood samples were collected from each group, and serum renal function indexes such as urea ni- trogen (BUN) and creatinine (Scr) were detected by colorimetry. Renal tissue samples were taken from each group, and the histopathological changes of kidney were observed by HE staining, the content of SOD and MDA in renal tissues were detected by colorimetry, and the expression levels of Klotho and Nrf2 protein in renal tissues were detected by Western blotting. Results Compared with the sham group, serum creatinine and urea nitrogen increased, renal tubular injury was aggravated, SOD activity decreased, MDA content increased, the expression of Klotho protein in the renal tissues de- creased, and the expression of Nrf2 proteion increased in the I/R group (P<0.05 or P<0.01). Compared with the I/R group, the serum levels of creainine and urea nitrogen decreased, renal tubular injury was alleviated, SOD activity in- creased, MDA content decreased, the Klotho protein expression increased, and the Nrf2 protein expression decreased in the I/R + NaHS group （P<0. 05 or P<0. 01）. Conclusion NaHS can alleviate renal I/R injury in rats with acute renal ischemia， and its mechanism may be related to up-regulating Klotho protein expression and reducing oxidative stress. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Anhui Agricultural Sciences is the property of Journal of Anhui Agricultural Sciences Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the protologue of Indocalamus semifalcatus (H. R. Zhao et Y. L. Yang) T. P. Yi, there were only parts of vegetative organs reported. Based on field population investigation, indoor stereoscopic anatomy and scanning electron microscope (SEM), its reproductive organs, complete vegetative organs and micromorphological features of the abaxial leaf epidermis, were described and illustrated herein, and its geographical distribution was also updated. The results were as follows: (1) Reproductive organ features: panicle, spikelet and spike densely white pubescent, glume, pelea and lemma both smooth and glabrous, stamens 3, anthers purple, stigmas 2, white, feathery. (2) Vegetative features: culms up to 4.5 m tall, up to 2 cm in diameter, culm sheath auricle semifalcate or weak, culm sheath erect close to culm, foliage auricle weak or absent, ligule margin with densely ciliate; both sides of leaf blade homochromatic and glabrous. (3) Micromorphologic characteristics of the abaxial leaf: stomatal apparatus invisible, eight to ten elongated papillae covered the stomatal apparatus, silica bodies saddle-shaped, micro-hairs and macro-hairs both absent. (4) The new distribution area was Guanyin Mountain of Guiyang in Guizhou. The species is the most similar to I. longiauritus Hand.-Mazz., differed by culm sheath and leaf sheath with auricles semifalcate or rare, culm up to 4.5 m tall and 2 cm in diameter. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Agrometeorology is the property of Editorial Board of Chinese Journal of Agrometeorology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Clinical Nursing in Practice is the property of Journal of Clinical Nursing in Practice (Editorial Board, Shanghai Jiao Tong University Press) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To investigate the expression of lncRNA SNHG8 in placenta accrete (PA) and its effect on trophoblast invasion and migration. Methods qRT-PCR was used to detect the expression of lncRNA SNHG8 in placenta tissue of 30 cases in PA group and 30 cases in control group, and the correlation between lncRNA SNHG8 expression and prenatal ultrasound score of 30 cases in PA group was analyzed. Transwell and scratch assay were used to detect the effect of lncRNA SNHG8 interference on the invasion and migration of human chorionic trophoblast cells (HTR8/SVneo cells), and western blot was used to detect the expression of MMP-2 and MMP-9. The downstream targets of lncRNA SNHG8 were predicted by StarBase software, and the expression of lncRNA SNHG8 was detected in placental tissues of the two groups. Dual luciferase reporter assay was used to detect the targeting relationship between lncRNA SNHG8 and miR-542-3p. Results Compared with that of the control group, the expression of lncRNA SNHG8 was up-regulated in the placenta tissue of the PA group(P < 0.05), and it was positively correlated with prenatal ultrasound score. Interference with lncRNA SNHG8 inhibited the invasion and migration of trophoblast cells(P < 0.05); the protein expression of MMP-9 and MMP-2 also decreased significantly (P < 0.05). Biological prediction indicates that miR-542-3p had a binding site with lncRNA SNHG8, and miR-542-3p expression was down-regulated in PA placental tissue(P < 0.05). Dual luciferase reporter assay confirmed that lncRNA SNHG8 could target miR-542-3p. Compared with si-SNHG8+inhibitor-NC, co-transfection of si-SNHG8 and miR-542-3p inhibitor enhanced the invasion and migration ability of trophoblast cells(P < 0.05). Conclusion lncRNA SNHG8 is highly expressed in PA and is related to the severity of PA. LncRNA SNHG8 promotes the invasion and migration of trophoblast by regulating the level of miR-542-3p. The study suggests that lncRNA SNHG8 plays an important role in the invasion and migration of PA trophoblast cells, which is expected to be a clinical diagnostic biomarker and therapeutic target. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Modern Laboratory Medicine is the property of Journal of Modern Laboratory Medicine Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Journal of Central China Normal University is the property of Huazhong Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Management / Gongcheng Guanli Xuebao is the property of Journal of Engineering Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Klotho是近年来发现的一种抗衰老基因，主要表达于肾脏，具有抗氧化、抗凋亡、抗炎等多重生物学效应。 急性肾损伤 (AKI)是临床常见疾病，发病急且致死率高，极易进展为慢性肾脏病，甚至走向肾衰竭。氧化应激是AKI 发病机制中的重要一环，而Klotho可通过多种信号转导通路减轻氧化应激，保护脏器免受损伤或延缓疾病进展，在 不同病因导致 AKI发生的过程中均具有肾脏保护作用。研究显示，Klotho可通过激活叉头转录因子 (FoxOs)、核因 子红系 2 相关因子 2 (Nrf2)、环磷酸腺苷/蛋白激酶 A (cAMP/PKA)信号通路、减轻内质网应激、减轻线粒体功能障 碍、促进促红细胞生成素受体 (EPOR)表达等抑制氧化应激反应，从而减轻AKI。 [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of West China Journal of Stomatology is the property of Sichuan University, West China College of Stomatology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Straw is an important source of roughage for ruminants, but the high content of cellulose and lignin content in straw results in the low utilization rate of straw feed relatively. After the straw is puffed, some of the fibers are separated into filaments, which makes the straw surface rough, conducive to microbial adhesion and reproduction, can better play the microbial degradation function, and then improve the feed quality and feed nutrient conversion rate. The paper reviews the effects of extruded straw and biological fermentation on straw and their application in ruminant production, in order to provide reference for further application of extruded straw fermented feed in animal production. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)