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The Electromagnetically Induced Transparency of Quasi-A-type Four-level Atom System at Low Light Levels
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作者 Li-ying Zhang Zheng-dong Liu Jun Chen 《量子光学学报》 CSCD 北大核心 2006年第B08期81-81,共1页
关键词 线 EIT
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Water, Sanitation and Hygiene in Lower-Level Health Care Facilities of Dar es Salaam Region in Tanzania: Status towards Achieving the Sustainable Development Goals and Way Forward
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作者 Mariam Mahamudu Hussein Mohamed +8 位作者 Michael Habtu Dennis Rweyemamu Anyitike Mwakitalima Amour Seleman Erick Mgina Khalid Massa Grace Saguti Andre Arsene Bita Fouda Zabulon Yoti 《Advances in Infectious Diseases》 CAS 2024年第1期279-295,共17页
Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) ... Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) has set a target for each United Nations member state to reach by 2030. Each member state is required to reach by 2022, 2025 and 2030 at least 60%, 80% and 100%, respectively of basic level of service of the five elements which are water, sanitation, hygiene, waste management and environmental cleaning. Methods: This study aimed to evaluate and document the current state of basic water, sanitation, and hygiene services in all lower-level health care facilities in the Dar es Salaam region of Tanzania as of July 2022. A cross-sectional study was conducted in 99 public dispensaries in the Dar es Salaam region’s five councils: Ubungo, Kigamboni, Kinondoni and Temeke Municipalities, and Ilala City. The interviewee form and observational checklists were both digitalized using the Kobo tool software. The respondents were health care facility in-charges or nurse in-charges. Data were downloaded, validated, and imported to Stata version 15 for analysis. Results: The basic WASH level per JMP is far below the target in 2022. Each member state by 2022 is required to reach at least 60% of the basic level of service of each element. We found a low coverage of basic WASH in the 99 dispensaries included in this study. The basic WASH coverage was met in only 10 (10.1%) of the dispensaries, while the remaining 89 (89.9%) dispensaries fall on limited WASH services. Conclusion: This study revealed lower coverage of basic WASH services in dispensaries. An urgent need is required to improve the status of WASH in all the dispensaries and facilitate the provision of quality health care services, patient safety and reduce health care associated infections. 展开更多
关键词 Dispensaries low level Health Care Facilities Service levels Basic WASH Dar es Salaam
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Comparison of Low Stress Mechanical Properties of Light Weight Wool and Wool Blend Fabrics using the KES-F and FAST Instruments 被引量:1
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作者 王革辉 张渭源 +1 位作者 Postle Ron Phillips David 《Journal of China Textile University(English Edition)》 EI CAS 2000年第4期99-102,共4页
This study compares the test results of the FAST (Fabric Assurance by Simple Testing) with those of the KES - F (Kawabata Evaluation Systems for Fabrics) for a range of nineteen light weight wool and wool blend fabric... This study compares the test results of the FAST (Fabric Assurance by Simple Testing) with those of the KES - F (Kawabata Evaluation Systems for Fabrics) for a range of nineteen light weight wool and wool blend fabrics in terms of the low - stress mechanical properties of bending, shear, and tensile deformation. It is found that there are very significant correlations between the corresponding parameters for extensibility and shear rigidity obtained from the test results of the two systems. The correlation between the values of bending rigidity obtained from the two systems is only moderate. Furthermore, for the fabrics tested in this study, the values of bending rigidity, shear rigidity, and extensibility measured using the KES - F instruments are higher than those of the corresponding parameters measured using the FAST instruments. The linear regression equation is given for each pair of corresponding parameter. 展开更多
关键词 low stress MECHANICAL properties the KES - F SYSTEM the FAST SYSTEM light weight WOOL FABRICS
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Effective Dose Screening of Low Level Red Light in Different Cell Indexes
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作者 Qiu Shuting Pan Zhi +3 位作者 Jiang Xiao Hu Fan Zhang Hao Wu Fengjuan 《China Detergent & Cosmetics》 CAS 2023年第3期41-50,共10页
The low level red light irradiation dose that produced positive response on different cell indexes was selected through experiments.In fibroblast detection model,the low level red light irradiation dose that had posit... The low level red light irradiation dose that produced positive response on different cell indexes was selected through experiments.In fibroblast detection model,the low level red light irradiation dose that had positive response to the four indicators of mitochondrial membrane potential,ATP release,cell migration and collagen synthesis was screened.The experimental results showed that low level red light with a irradiation dose of 2 J/cm^(2) had a positive response to the above four indexes in fibroblast.The test model on fibroblast was later transferred to dermal papilla cells for further experimental verification.The results showed that low level red light with a irradiation dose of 2 J/cm^(2) also had a positive response to the four indicators of dermal papilla cells,namely,mitochondrial membrane potential,ATP release,cell proliferation rate and collagen synthesis.It is proved that the low level red light with a irradiation dose of 2 J/cm^(2) could improve the mitochondrial function,cell migration and collagen synthesis of fibroblast and dermal papilla cell,thus providing energy for cell activities,improving cell repair ability and cell anti-aging ability. 展开更多
关键词 low level red light dose screening mitochondrial function collagen synthesis cell migration
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Thermal stratification level of low sidewall air supply with air-conditioning system in large space 被引量:3
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作者 黄晨 蔡宁 高雪垒 《Journal of Central South University》 SCIE EI CAS 2009年第S1期166-170,共5页
The thermal stratification level of low sidewall air supply system in large space was defined. Depending on the experiment of low sidewall air supply in summer 2008,the thermal stratification level was studied by simu... The thermal stratification level of low sidewall air supply system in large space was defined. Depending on the experiment of low sidewall air supply in summer 2008,the thermal stratification level was studied by simulation. Based on the simulation of experiment condition,the air velocity and vertical temperature distribution in a large space were simulated at different air-outlet velocities,and then the thermal stratification level line was obtained. The simulation results well match with the experimental ones and the average relative error is 3.4%. The thermal stratification level is heightened by increasing the air-outlet velocity with low sidewall air supply mode. It is concluded that when air-outlet velocity is 0.29 m/s,which is the experimental case,a uniform thermal environment in the higher occupied zone and a stable stratification level are formed. When the air-outlet velocity is low,such as 0.05 m/s,the thermal stratification level is too low and the air velocity is too small to meet the human thermal comfort in the occupied zone. So,it would be reasonable that the air-outlet velocity may be designed as 0.31 m/s if the height of the occupied zone is 2 m. 展开更多
关键词 large space low SIDEWALL AIR supply thermal STRATIFICATION level numerical simulation air-outlet VELOCITY
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The electromagnetically induced transparency in the Y-type four-level atom system at low light levels 被引量:3
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作者 ZHANG Liying LIU Zhengdong CHEN Jun 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2005年第5期593-599,共7页
In this paper a Y-type four-level atom interacting with external fields system is investigated. It is shown that increasing the control field can reduce the probe absorption, the electromagnetically induced transparen... In this paper a Y-type four-level atom interacting with external fields system is investigated. It is shown that increasing the control field can reduce the probe absorption, the electromagnetically induced transparency (EIT) and gain can be obtained if the parameters are taken appropriately. An interesting phenomenon is found that the system appears to be probe gain in a large region if the external fields Rabi phases are taken appropriately, too. 展开更多
关键词 QUANTUM optics the nonlinear effect at low light levels EIT SPONTANEOUS emission QUANTUM interference.
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Addendum to: An Approach to Hierarchical Clustering via Level Surfaces and Convexity
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作者 Jerome Malitz Seth Malitz 《Intelligent Information Management》 2010年第5期299-305,共7页
This article is an addendum to the 2001 paper [1] which investigated an approach to hierarchical clustering based on the level sets of a density function induced on data points in a d-dimensional feature space. We ref... This article is an addendum to the 2001 paper [1] which investigated an approach to hierarchical clustering based on the level sets of a density function induced on data points in a d-dimensional feature space. We refer to this as the “level-sets approach” to hierarchical clustering. The density functions considered in [1] were those formed as the sum of identical radial basis functions centered at the data points, each radial basis function assumed to be continuous, monotone decreasing, convex on every ray, and rising to positive infinity at its center point. Such a framework can be investigated with respect to both the Euclidean (L2) and Manhattan (L1) metrics. The addendum here puts forth some observations and questions about the level-sets approach that go beyond those in [1]. In particular, we detail and ask the following questions. How does the level-sets approach compare with other related approaches? How is the resulting hierarchical clustering affected by the choice of radial basis function? What are the structural properties of a function formed as the sum of radial basis functions? Can the levels-sets approach be theoretically validated? Is there an efficient algorithm to implement the level-sets approach? 展开更多
关键词 Hierarchical Clustering level Sets level SURFACES Radial Basis Function CONVEX Heat Gravity light Cluster Validation Ridge Path Euclidean DISTANCE Manhattan DISTANCE Metric
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Studies on the oxidative modification of low density lipoprotein induced by ultraviolet light and the protective effect of green tea polyphenols
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作者 丁振华 陈瑷 +1 位作者 周玫 方允中 《Journal of Medical Colleges of PLA(China)》 CAS 1992年第2期121-126,共6页
Uitraviolet(UV)light irradiation acting on human low density lipoprotein(LDL)couldgive rise to oxidative modification of LDL.Thiobarbituric acid reactive substances(TBARS),rela-five electrophorefic mobility(REM... Uitraviolet(UV)light irradiation acting on human low density lipoprotein(LDL)couldgive rise to oxidative modification of LDL.Thiobarbituric acid reactive substances(TBARS),rela-five electrophorefic mobility(REM),relative fluorescence intensity at 420 nm(the excitation wavelength was 360nm)and lipid conjugated dienes of UV-irradiated LDL were all elevated withthe increase of irradiation time.Addition of 0.01% EDTA into the irradiation system could inhi-bit this reaction,but the effect was not so potent as that induced in the Cu<sup>2+</sup>-PBS-LDLoxidative modification system China green tea polyphenols(CGTP),on the other hand,had aneffective inhibitory effect with obvious dose-effect relationship.It was proposed that lipidperoxidation of LDL induced by free radicals which were generated from UV-irradiation andthe inhibitory effect of CGTP was attributed to its strong antioxidative action. 展开更多
关键词 ATHEROSCLEROSIS low density lipopmtein LIPOPEROXIDATION ANTIOXIDANTS ULTRAVIOLET light irradiation ANIMAL mice human
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Anthropogenic activity,hydrological regime,and light level jointly influence temporal patterns in biosonar activity of the Yangtze finless porpoise at the junction of the Yangtze River and Poyang Lake,China
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作者 Peng-Xiang Duan Zhi-Tao Wang +4 位作者 Tomonari Akamatsu Nick Tregenza Guang-Yu Li Ke-Xiong Wang Ding Wang 《Zoological Research》 SCIE CSCD 2023年第5期919-931,共13页
Under increasing anthropogenic pressure,species with a previously contiguous distribution across their ranges have been reduced to small fragmented populations.The critically endangered Yangtze finless porpoise(Neopho... Under increasing anthropogenic pressure,species with a previously contiguous distribution across their ranges have been reduced to small fragmented populations.The critically endangered Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis),once commonly observed in the Yangtze River-Poyang Lake junction,is now rarely seen in the river-lake corridor.In this study,static passive acoustic monitoring techniques were used to detect the biosonar activities of the Yangtze finless porpoise in this unique corridor.Generalized linear models were used to examine the correlation between these activities and anthropogenic impacts from the COVID-19 pandemic lockdown and boat navigation,as well as environmental variables,including hydrological conditions and light levels.Over approximately three consecutive years of monitoring(2020–2022),porpoise biosonar was detected during 93%of logged days,indicating the key role of the corridor for finless porpoise conservation.In addition,porpoise clicks were recorded in 3.80%of minutes,while feeding correlated buzzes were detected in 1.23%of minutes,suggesting the potential existence of localized,small-scale migration.Furthermore,both anthropogenic and environmental variables were significantly correlated with the diel,lunar,monthly,seasonal,and annual variations in porpoise biosonar activities.During the pandemic lockdown period,porpoise sonar detection showed a significant increase.Furthermore,a significant negative correlation was identified between the detection of porpoise click trains and buzzes and boat traffic intensity.In addition to water level and flux,daylight and moonlight exhibited significant correlations with porpoise biosonar activities,with markedly higher detections at night and quarter moon periods.Ensuring the spatiotemporal reduction of anthropogenic activities,implementing vessel speed restrictions(e.g.,during porpoise migration and feeding),and maintaining local natural hydrological regimes are critical factors for sustaining porpoise population viability. 展开更多
关键词 Yangtze finless porpoises Yangtze River Poyang Lake Pandemic lockdown Boat traffic Hydrological regime light level
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Efficacy of super-pulsed 905 nm Low Level Laser Therapy (LLLT) in the management of Traumatic Brain Injury (TBI): A case study 被引量:2
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作者 William Stephan Louis J. Banas +1 位作者 Matthew Bennett Huseyin Tunceroglu 《World Journal of Neuroscience》 2012年第4期231-233,共3页
Traumatic brain injury is a major health concern worldwide with massive financial and social impact. Conventional treatments primarily focus on the prevention of further damage to the brain parenchyma, while failing t... Traumatic brain injury is a major health concern worldwide with massive financial and social impact. Conventional treatments primarily focus on the prevention of further damage to the brain parenchyma, while failing to address the already existent symptoms. Previous clinical studies have shown that Low Level Laser Therapy (LLLT) can significantly reduce pain and induce temporary vasodilation in capillaries, which the authors hypothesize can be used to improve the quality of life in TBI patients by treating their current symptoms, which are predominately migraine-like headaches. This case report illustrates the use of LLLT in the treatment of a patient with a TBI and the great clinical success achieved in the reduction of pain, as measured by VAS—achievable within five treatments of 10 minutes in duration. 展开更多
关键词 TRAUMATIC Brain Injury low level Laser Therapy LLLT Chronic MIGRAINES HEADACHES
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Induction of Autologous Bone-Marrow Stem Cells by Low-Level Laser Therapy Has Beneficial Effects on the Kidneys Post-Ischemia-Reperfusion Injury in the Rat 被引量:1
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作者 Hana Tuby Lidya Maltz Uri Oron 《Journal of Biomedical Science and Engineering》 2014年第8期453-463,共11页
Acute renal failure has a 50% - 80% mortality rate. Currently, treatment options for this life-threatening disease are limited. Low-level laser therapy (LLLT) has been found to modulate biological activity. The aim of... Acute renal failure has a 50% - 80% mortality rate. Currently, treatment options for this life-threatening disease are limited. Low-level laser therapy (LLLT) has been found to modulate biological activity. The aim of the present study was to investigate the possible beneficial effects of laser application to stem cells in the bone marrow, on the kidneys of rats that had undergone ischemia-reperfusion injury (IRI). IRI was induced by occlusion of the renal artery to 3- and 7-month-old rats for 15 or 30 minutes. In an additional experiment IRI was applied to both kidneys for 20 min each in 2-3-month-old rats. Rats were then divided randomly into two groups of control and laser-treated. Laser therapy (Ga-Al-As 810 nm, 200 mW output for 2 min) was applied to the bone marrow 1 and 7 days post-IRI to the kidneys, and rats were sacrificed 2 weeks later. Histomorphometry and immunohistochemistry were performed on kidney sections and blood markers for kidney function. Quantitative histomorphometric analysis revealed a reduction in dilatation of the renal tubules, restored structural integrity of the renal tubules, and reduced necrosis in the laser-treated rats as compared to the control, non-laser-irradiated group. C-kit positive cell density in kidneys post-IRI and laser-treatment was significantly (p = 0.015) 3.2-fold higher compared to the control group. Creatinine and blood urea nitrogen content were significantly lower in the laser-treated rats as compared to control. It is concluded that LLLT application to the bone marrow (BM) causes a significant increase in the density of mesenchymal stem cells in the kidneys post-IRI, probably by induction of stem cells in the BM, which subsequently migrate to the IRI kidney, significantly reducing the pathological features of the kidney and increasing kidney function post IRI. 展开更多
关键词 Kidney Mesenchymal Stem Cells (MSCs) low-level Laser Therapy (LLLT) ISCHEMIA-REPERFUSION Injury (IRI)
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Silymarin in non alcoholic fatty liver disease 被引量:18
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作者 Fulvio Cacciapuoti Anna Scognamiglio +2 位作者 Rossella Palumbo Raffaele Forte Federico Cacciapuoti 《World Journal of Hepatology》 CAS 2013年第3期109-113,共5页
AIM: This study was undertaken to evaluate the hepatic effects of silybum marianum on non alcoholic fatty liver disease (NAFLD). METHODS: In 72 patients affected by NAFLD, main metabolic, hepatic and anti-inflammatory... AIM: This study was undertaken to evaluate the hepatic effects of silybum marianum on non alcoholic fatty liver disease (NAFLD). METHODS: In 72 patients affected by NAFLD, main metabolic, hepatic and anti-inflammatory parameters were assayed after 3 mo of a restricted diet and before silymarin treatment (twice a day orally). The brightness of liver echography texture (hepatorenal ratio brightness) was also defined at same time. These evaluations were repeated after 6 mo of treatment. RESULTS: Serum levels of some metabolic and anti-inflammatory data nonsignificantly lowered after 6 mo of silymarin. On the contrary, Steato test, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transpeptidase were significantly (P < 0.001) reduced. Instead, the AST/ALT ratio unchanged. Finally, the hepatorenal brightness ratio, as an index of hepatic steatosis, significantly (P < 0.05) dropped. CONCLUSION: The obtained results indicate that silymarin appears to be effective to reduce the biochemical, inflammatory and ultrasonic indices of hepatic steatosis. Some parameters indicative of early stage of atherosclerosis were also lowered. 展开更多
关键词 Alanine AMINOTRANSFERASE Aspartate AMINOTRANSFERASE Total CHOLESTEROL Gamma-glutamyl transpeptidase Non alcoholic fatty liver disease SILYMARIN Steato TEST Hepatorenal ultrasonographic index Fasting glucose level High DENSITY LIPOPROTEIN and low DENSITY LIPOPROTEIN CHOLESTEROL Homeostatic model assessment insulin resistance TEST
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Design of a low-sidelobe-level and wideband dielectric resonator antenna array for 60 GHz millimeter wave communication
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作者 Lin Jiahong Shen Wenhui +1 位作者 Ren Fang Fan Di 《High Technology Letters》 EI CAS 2018年第4期402-407,共6页
A low-sidelobe-level( SLL) and wideband linear dielectric resonator antenna( DRA) array is proposed for 60 GHz millimeter wave communication. The array consists of 10 wideband DRAs which work at 60 GHz and it is fed b... A low-sidelobe-level( SLL) and wideband linear dielectric resonator antenna( DRA) array is proposed for 60 GHz millimeter wave communication. The array consists of 10 wideband DRAs which work at 60 GHz and it is fed by a Chebyshev feeding network to get a low SLL. To avoid the influence from the feeding network,a U-shaped substrate and a conformal ground are used,which can separate the DRA array and the feeding network. The parameter analysis and simulated results are presented. 展开更多
关键词 dielectric RESONATOR antenna array low-sidelobe-level(SLL) WIDEBAND 60 GHZ MILLIMETER wave communication
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Predictive Value of Serum pgRNA on HBeAg Clearance in Patients with Chronic Hepatitis B with Low HBeAg Levels Treated with Pegylated Interferon
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作者 Yu Li Yifei Lyu +1 位作者 Feng-Yu Xi Ying Gao 《Journal of Clinical and Nursing Research》 2023年第4期165-169,共5页
Objective:To study the predictive value of serum pregenomic RNA(pgRNA)on HBeAg clearance in patients with chronic hepatitis B with low HBeAg levels during pegylated interferon therapy.Methods:Twenty chronic hepatitis ... Objective:To study the predictive value of serum pregenomic RNA(pgRNA)on HBeAg clearance in patients with chronic hepatitis B with low HBeAg levels during pegylated interferon therapy.Methods:Twenty chronic hepatitis B patients with HBeAg positive and quantitative<50S/CO were selected for this study.The subjects underwent pegylated interferon therapy for 48-96 weeks and were followed up in the outpatient clinic after treatment.The patients were then divided into groups based on whether their HbeAg turned negative.The predictive ability of each indicator for HBeAg negative conversion was evaluated in the HBeAg negative group and the HBeAg positive group.Results:The results of logistic regression analysis suggested that pgRNA and HBcrAg were better indicators for predicting the clearance of HBeAg after treatment.Conclusion:For patients with chronic hepatitis B with low HBeAg levels,pgRNA is a good indicator in predicting HBeAg clearance during pegylated interferon therapy. 展开更多
关键词 Serum pgRNA Pegylated interferon low HBeAg level Chronic hepatitis B HBeAg clearance Predictive value
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Effect of autologous mesenchymal stem cells induced by low level laser therapy on cardiogenesis in the infarcted area following myocardial infarction in rats
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作者 Hana Tuby Tali Yaakobi +3 位作者 Lidya Maltz Yaakov Delarea Orit Sagi-Assif Uri Oron 《Journal of Biomedical Science and Engineering》 2013年第8期24-31,共8页
In this study, we investigated the hypothesis that photobiostimulation by low-energy laser therapy (LLLT) applied to the bone marrow (BM) of myocardial infarcted rats may attenuate the scarring processes that follow m... In this study, we investigated the hypothesis that photobiostimulation by low-energy laser therapy (LLLT) applied to the bone marrow (BM) of myocardial infarcted rats may attenuate the scarring processes that follow myocardial infarction (MI). Wistar rats underwent experimental MI. LLLT (Ga-Al-As diode laser) was applied to the BM of the exposed tibia at different time intervals post-MI (4 hrs, 48 hrs and 5 days). Sham-operated infarcted rats served as control. Infarct size was significantly reduced (55%) in the laser-treated rats as compared to the control non-treated rats, at 2 weeks post-MI. A significant 3-fold increase was observed in the density of desmin immunopositive stained cells 14 days post-MI in the infarcted area of the laser-treated rats as compared to the non-laser-treated controls. The electron microscopy from the control infarcted rat hearts revealed a typical interphase area between the intact myocardium and the infarcted area, with conspicuous fibroblasts with collagen deposition dispersed among them. In rats that were laser treated (to BM), the interphase zone demonstrated cells with different intracellular structures. There was also a significant increase in the percentage of c-kit positive cells and macrophages in the circulating blood of the laser treated rats as compared to control non treated ones. In the majority of the cells clusters of myofibrils anchored to well-developed Z-lines and structures resembling the morphological characteristics of mature intact cardiomyocytes were evident. In conclusion, LLLT to the BM of rats post-MI induces cardiogenesis mainly at the borders of the infarcted area in the heart. 展开更多
关键词 low-level Laser Therapy Myocardial INFARCTION Macrophage DESMIN ULTRASTRUCTURE C-KIT Positive Cells
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Design of Irregular QC-LDPC Code Based Multi-Level Coded Modulation Scheme for High Speed Optical Communication Systems 被引量:7
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作者 Liqian Wang Dongdong Wang +3 位作者 Yongjing Ni Xue Chen Midou Cui Fu Yang 《China Communications》 SCIE CSCD 2019年第5期106-120,共15页
In this paper, we focus on the design of irregular QC-LDPC code based multi-level coded modulation(MLCM) scheme by jointly optimizing the component code rate and the degree distribution of the irregular QC-LDPC compon... In this paper, we focus on the design of irregular QC-LDPC code based multi-level coded modulation(MLCM) scheme by jointly optimizing the component code rate and the degree distribution of the irregular QC-LDPC component code. Firstly, the sub-channel capacities of MLCM systems is analyzed and discussed, based on which the optimal component code rate can be obtained. Secondly, an extrinsic information transfer chart based two-stage searching algorithm is proposed to find the good irregular QC-LDPC code ensembles with optimal component code rates for their corresponding sub-channels. Finally, by constructing the irregular QC-LDPC component codes from the designed ensembles with the aim of possibly enlarging the girth and reducing the number of the shortest cycles, the designed irregular QC-LDPC code based 16QAM and 64QAM MLCM systems can achieve 0.4 dB and 1.2 dB net coding gain, respectively, compared with the recently proposed regular QC-LDPC code based 16QAM and 64QAM MLCM systems. 展开更多
关键词 quasi-cyclic low-DENSITY parity check (QC-LDPC) code irregular extrinsic INFORMATION transfer(EXIT) chart generalized mutual information(GMI) MULTI-level coded modulation(MLCM)
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Low temperature-mediated repression and far-red light-mediated induction determine morning FLOWERING LOCUS T expression levels
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作者 Hayeon Kim Hye Won Kang +4 位作者 Dae Yeon Hwang Nayoung Lee Akane Kubota Takato Imaizumi Young Hun Song 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2024年第1期103-120,共18页
In order to flower in the appropriate season,plants monitor light and temperature changes and alter downstream pathways that regulate florigen genes such as Arabidopsis(Arabidopsis thaliana)FLOWERING LOCUS T(FT).In Ar... In order to flower in the appropriate season,plants monitor light and temperature changes and alter downstream pathways that regulate florigen genes such as Arabidopsis(Arabidopsis thaliana)FLOWERING LOCUS T(FT).In Arabidopsis,FT messenger RNA levels peak in the morning and evening under natural long-day conditions(LDs).However,the regulatory mechanisms governing morning FT induction remain poorly understood.The morning FT peak is absent in typical laboratory LDs characterized by high red:far-red light(R:FR)ratios and constant temperatures.Here,we demonstrate that ZEITLUPE(ZTL)interacts with the FT repressors TARGET OF EATs(TOEs),thereby repressing morning FT expression in natural environments.Under LDs with simulated sunlight(R:FR=1.0)and daily temperature cycles,which are natural LD-mimicking environmental conditions,FT transcript levels in the ztl mutant were high specifically in the morning,a pattern that was mirrored in the toe1 toe2 double mutant.Low night-to-morning temperatures increased the inhibitory effect of ZTL on morning FT expression by increasing ZTL protein levels early in the morning.Far-red light counteracted ZTL activity by decreasing its abundance(possibly via phytochrome A(phyA))while increasing GIGANTEA(GI)levels and negatively affecting the formation of the ZTL-GI complex in the morning.Therefore,the phyA-mediated high-irradiance response and GI play pivotal roles in morning FT induction.Our findings suggest that the delicate balance between low temperature-mediated ZTL activity and the far-red light-mediated functions of phyA and GI offers plants flexibility in fine-tuning their flowering time by controlling FT expression in the morning. 展开更多
关键词 far-red light FlowERING LOCUS T flowering time GIGANTEA low night-to-morning temperature natural long days phytochrome A red to far-red ratio ZEITLUPE
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HIV Drug Resistance Profiles and Clinical Outcomes in Patients with Viremia Maintained at Very Low Levels 被引量:2
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作者 Michael R. Jordan Julie Winsett +6 位作者 Aileen Tiro Vuth Bau Rony S. Berbara Christopher Rowley Nobel Bellosillo Christine Wanke Eoin P. Coakley 《World Journal of AIDS》 2013年第2期71-78,共8页
We describe an observational study of clinical, virologic and drug resistance profiles in HIV-positive antiretroviral adherent subjects with stable low level viremia (LLV) 50 - 1000 copies/mL for more than 12 months. ... We describe an observational study of clinical, virologic and drug resistance profiles in HIV-positive antiretroviral adherent subjects with stable low level viremia (LLV) 50 - 1000 copies/mL for more than 12 months. Subjects were followed from time of first detectable viral load (VL). In total, 102 episodes of LLV were detected among 80 individuals. The median (mean, range) HIV copy number at genotyping was 250 (486, - 3900) copies/mL after 14 (17.9, 0 - 58) months of LLV. Few patients maintained LLV for the entire 9 years period of observation, with half (52%) experiencing viremic progression following a stable period of LLV either spontaneously or after treatment interruption or failed regimen intensification. In the setting of prolonged periods of sustained LLV, mean duration 22 (range 8 - 106) months, drug resistance (DR) was almost universal. Resistance to ≥1 on-treatment drugs was defined in 97% of specimens and DR to all drugs in the treatment regimen in over half of all patients. Evolution of DR mutations during the period of LLV was observed in 20/28 (71%) subjects with specimens available for follow-up testing. This evolution was associated with viremic progression to levels >1000 copies/mL (p = 0.03). Our data suggest that DR present in patients with LLV is likely to impact long term clinical outcomes, highlighting the importance of optimizing techniques to detect the presence of drug resistant HIV in the setting of LLV and the need for larger prospective studies to assess the emergence of DR in the setting of sustained LLV and the impact of this DR on treatment outcomes. 展开更多
关键词 HIV low level VIREMIA Treatment Experienced PATIENTS HIV DRUG RESISTANCE
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Simulation of Quantum Noise in the Low-Light-Level Imaging System 被引量:3
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作者 邹正峰 芦汉生 +1 位作者 白廷柱 高稚允 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期186-190,共5页
A mathematical model of quantum noise having much effect on the low light imaging system is set up. To simulate the quantum noise, the random numbers obeying noise distribution must be formed and are weighted on the... A mathematical model of quantum noise having much effect on the low light imaging system is set up. To simulate the quantum noise, the random numbers obeying noise distribution must be formed and are weighted on the basis of the model created. Three uniform random sequences are built by the linear congruential method, of which two are used to form integer number and decimal fraction parts of the new random sequence respectively and the third to shuffle the new sequence. And then a Gauss sequence is formed out of uniform distribution by a function transforming method. It actualizes the simulation in real time of quantum noise in the low light imaging system, where video flow is extracted in real time, the noise summed up and played back side by side with the original video signs by a simulation software. 展开更多
关键词 SIMULATION quantum noises low light level imaging
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MRPⅡ/ERP中混合型物料需求计划的研究与实现 被引量:2
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作者 莫登耀 张阿卜 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第4期475-478,共4页
在企业MRPⅡ/ERP管理中,缩短最终产品的累计提前期以提高响应客户需求的反应速度和降低物料库存是两个相互矛盾的目标.以部分企业的实际问题为应用背景,指出了典型的MRPⅡ/ERP系统在应用于生产半定制型产品的企业时MPS和MRP失效的问题,... 在企业MRPⅡ/ERP管理中,缩短最终产品的累计提前期以提高响应客户需求的反应速度和降低物料库存是两个相互矛盾的目标.以部分企业的实际问题为应用背景,指出了典型的MRPⅡ/ERP系统在应用于生产半定制型产品的企业时MPS和MRP失效的问题,并且分析了失效的原因.提出了一种把“订货点法”、“物料需求计划(MRP)”和“制造资源计划(MRPⅡ)”这些管理模式相互融合的新的物料管理方法,同时使用面向对象的技术和UML建模工具,对混合型的物料需求计划系统的核心部分给出了详细的设计和实现方案,也针对在实际工程设计过程中比较重要以及较难解决的问题提出了很好的解决方案. 展开更多
关键词 MRP ERP ERP 使 MPS
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