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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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Low level of hepatitis B viremia is associated with increased risk of hepatocellular carcinoma in compensated cirrhotic patients
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作者 Wei-Chun Lin Ke Lin +4 位作者 Ming-Kai Li Xiao Liu Yi-Fei Huang Xing Wang Bin Wu 《World Journal of Hepatology》 2024年第11期1321-1330,共10页
BACKGROUND Whether patients with compensated cirrhosis and low-level viremia(LLV)of hepatitis B should receive antiviral therapy(AVT)is still controversial,and published results are inconsistent.AIM To investigate the... BACKGROUND Whether patients with compensated cirrhosis and low-level viremia(LLV)of hepatitis B should receive antiviral therapy(AVT)is still controversial,and published results are inconsistent.AIM To investigate the link between LLV in compensated cirrhosis and prognosis concerning hepatocellular carcinoma(HCC),decompensation,and liver-related events.METHODS The PubMed,EMBASE,and Cochrane Library databases were searched up to March 5,2023.Outcomes of interest were assessed by pooled hazard ratios(HRs).The study was registered with PROSPERO(CRD42023405345).RESULTS Six cohort studies representing 3155 patients were included.Compared with patients with undetectable HBV DNA,patients with LLV was associated with increased risk of HCC(HR:2.06,95%CI:1.36-3.13;Q-statistic-P=0.07,I^(2)=51%)regardless of receiving AVT or not(AVT group:HR:3.14;95%CI:1.73-5.69;Qstatistic-P=0.60,I2=0%;un-AVT group:HR:1.73,95%CI:1.09-2.76;Q-statistic-P=0.11,I2=50%).The pooled results showed no statistical association between LLV and decompensation of cirrhosis(HR:2.06,95%CI:0.89-4.76;Q-statistic-P=0.04,I2=69%),and liver-related events(HR:1.84,95%CI:0.92-3.67;Q-statistic-P=0.03,I2=72%),respectively.Grading of Recommendations Assessment,Development and Evaluation assessment indicated moderate certainty for HCC,very low certainty for decompensation of cirrhosis and liver-related clinical events.CONCLUSION LLV in compensated cirrhotic patients is associated with increased risk of HCC,higher tendency for hepatic decompensation and liver-related events.Closer screening of HCC should be conducted in this population. 展开更多
关键词 low level of hepatitis B viremia Compensated cirrhosis Hepatocellular carcinoma Hepatic decompensation Liver-related events
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Low Level of Cystic Fibrosis Transmembrane Conductance Regulator Is Associated with Human Sperm Autophagy and Vitality
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作者 Jie Hu Han Liu +4 位作者 Chaoyan Ou Liangzhao Liu Linfeng Mo Xuming Liang Yonghua He 《Advances in Reproductive Sciences》 CAS 2024年第1期23-36,共14页
Low sperm motility is one of the main causes of male infertility. Cystic fibrosis transmembrane conductance regulator (CFTR, an anion channel protein) is related to the progressive motility of sperm. CFTR disruptor CF... Low sperm motility is one of the main causes of male infertility. Cystic fibrosis transmembrane conductance regulator (CFTR, an anion channel protein) is related to the progressive motility of sperm. CFTR disruptor CFTRinh-172 or forskolin (FSK) in this study were used to treat human sperm separately, and the rates of sperm autophagy and progressive motility, mitochondrial membrane potential (MMP) and ATP concentration, and the expression levels of related factors were detected to explore their relationship. It was showed that sperms treated with CFTRinh-172 or FSK reduced the levels of cAMP, CFTR and PKA, but increased sperm autophagy rate, expression levels of AMPK and LC3B. However, reactive oxygen species content had no significant difference. It was indicated that low level of CFTR performed with cAMP and its downstream effectors such as PKA and AMPK to regulate mitochondrial structure and function, leading to increased autophagy rate and reduced vitality of sperm. 展开更多
关键词 low level of Cystic Fibrosis Transmembrane Conductance Regulator Is Associated with Human Sperm Autophagy and Vitality
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A Low Mach Number IMEX Flux Splitting for the Level Set Ghost Fluid Method
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作者 Jonas Zeifang Andrea Beck 《Communications on Applied Mathematics and Computation》 2023年第2期722-750,共29页
Considering droplet phenomena at low Mach numbers,large differences in the magnitude of the occurring characteristic waves are presented.As acoustic phenomena often play a minor role in such applications,classical exp... Considering droplet phenomena at low Mach numbers,large differences in the magnitude of the occurring characteristic waves are presented.As acoustic phenomena often play a minor role in such applications,classical explicit schemes which resolve these waves suffer from a very restrictive timestep restriction.In this work,a novel scheme based on a specific level set ghost fluid method and an implicit-explicit(IMEX)flux splitting is proposed to overcome this timestep restriction.A fully implicit narrow band around the sharp phase interface is combined with a splitting of the convective and acoustic phenomena away from the interface.In this part of the domain,the IMEX Runge-Kutta time discretization and the high order discontinuous Galerkin spectral element method are applied to achieve high accuracies in the bulk phases.It is shown that for low Mach numbers a significant gain in computational time can be achieved compared to a fully explicit method.Applica-tions to typical droplet dynamic phenomena validate the proposed method and illustrate its capabilities. 展开更多
关键词 IMEX flux splitting level set method Ghost fluid method low Mach number flows
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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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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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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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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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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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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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Effects of low level laser treatment on the survival of axotomized retinal ganglion cells in adult Hamsters 被引量:1
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作者 Kwok-Fai So Mason Chin Pang Leung Qi Cui 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第21期1863-1869,共7页
Injury to axons close to the neuronal bodies in the mammalian central nervous system causes a large proportion of parenting neurons to degenerate. It is known that optic nerve transection close to the eye in rodents l... Injury to axons close to the neuronal bodies in the mammalian central nervous system causes a large proportion of parenting neurons to degenerate. It is known that optic nerve transection close to the eye in rodents leads to a loss of about half of retinal ganglion cells in 1 week and about 90% in 2 weeks. Using low level laser treatment in the present study, we demonstrated that treatment with helium-neon (660 nm) laser with 15 mW power could delay retinal ganglion cell death after optic nerve axotomy in adult hamsters. The effect was most apparent in the ifrst week with a short period of treatment time (5 minutes) in which 65–66% of retinal ganglion cells survived the optic nerve axotomy whereas 45–47% of retinal ganglion cells did so in optic nerve axotomy controls. We also found that single dose and early commencement of laser irradiation were important in protecting retinal ganglion cells following optic nerve axotomy. These ifndings thus convincingly show that appropriate laser treatment may be neuroprotective to retinal gan-glion cells. 展开更多
关键词 low level laser treatment retinal ganglion cells optic nerve injury NEUROPROTECTION mi-croglial proliferation optic nerve axotomy
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Effect of low level laser therapy on dental pulp during orthodontic movement 被引量:2
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作者 ngela Domínguez Rosa Emilia Ballesteros +1 位作者 Jairo Hernán Viáfara Oscar Mario Tamayo 《World Journal of Methodology》 2013年第2期19-26,共8页
AIM: To validate the protocol described here to be used in future clinical trials related to the effect of laser therapy on dental pulp. METHODS: Histologically treated samples from eight human healthy premolar teeth ... AIM: To validate the protocol described here to be used in future clinical trials related to the effect of laser therapy on dental pulp. METHODS: Histologically treated samples from eight human healthy premolar teeth obtained from the middle root level were distributed in four groups: group 1(G1) absolute control; group 2(G2) only laser irradiation; group 3(G3) exposed only to orthodontics; and group 4(G4) treated with orthodontics and laser. Laser treatment was performed at 830 nm wavelength, 100 mW(energy 80 J/cm2, 2.2 J), for 22 s in the vestibular surface and 22 s in the palatal surface, 1 mm away from the dental root mucosa. Three staining methods were performed: hematoxylin-eosin(HE), Masson's Trichrome method and Gomori's method.RESULTS: The pulp histology parameters were evaluated and the results classified in to 3 parts: an inflammatory response, soft tissue response(dental pulp) and hard tissue response(dentin and predentin). There was no inflammation(chronic or acute) in any of the evaluated groups. The zones of pulp necrosis were found in one premolar of G3 and in one of G4; in groups G2 and G4 there was higher angiogenesis than in the other two groups. G4 group presented the highest level of vascularization. A reduced nerve density was observed in G3. A G2 specimen showed increased nerve density. A higher rate of calcification was observed in G1 compared to G2. Denticles, either real or false, were observed in G1, G2 and G3. Sclerosis of dentin and focal dentin loss was observed among all the groups. Secondary dentin was present in one sample in G1 and G2. A necrosis zone was found in one sample of G3 and G4. No differences between groups were observed in the odontoblast irregularity layer but the layer was wider in the group treated with laser only. A notable difference was detected in reduction of the cell-free layer between the groups G1 and G4. The findings in pulp tissue favor its adaptative response against dental movement induced by orthodontics. No definitive conclusions may be derived as this is a pilot study. CONCLUSION: The protocol described here was shown to be an effective method to evaluate changes in dental pulp submitted to low level laser in teeth under orthodontic movement. 展开更多
关键词 low level laser therapy Pulpal Orthodontic movement Histological protocol DENTIN
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A Strategy for Magnifying Vibration in High-Energy Orbits of a Bistable Oscillator at Low Excitation Levels 被引量:2
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作者 王光庆 廖维新 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期195-198,共4页
This work focuses on how to maintain a high-energy orbit motion of a bistable oscillator when subjected to a low level excitation. An elastic magnifier (EM) positioned between the base and the bistable oscillator is... This work focuses on how to maintain a high-energy orbit motion of a bistable oscillator when subjected to a low level excitation. An elastic magnifier (EM) positioned between the base and the bistable oscillator is used to magnify the base vibration displacement to significantly enhance the output characteristics of the bistable oscillator. The dimensionless electromechanical equations of the bistable oscillator with an EM are derived, and the effects of the mass and stiffness ratios between the EM and the bistable oscillator on the output displacement are studied. It is shown that the jump phenomenon occurs at a lower excitation level with increasing the mass and stiffness ratios. With the comparison of the displacement trajectories and the phase portraits obtained from experiments, it is vMidated that the bistable oscillator with an EM can effectively oscillate in a high-energy orbit and can generate a superior output vibration at a low excitation level as compared with the bistable oscillator without an EM. 展开更多
关键词 EM A Strategy for Magnifying Vibration in High-Energy Orbits of a Bistable Oscillator at low Excitation levels
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Nocturnal Low-levelWinds and Their Impacts on Particulate Matter over the Beijing Area 被引量:2
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作者 Yong CHEN Junling AN +5 位作者 Yele SUN Xiquan WANG Yu QU Jingwei ZHANG Zifa WANG Jing DUAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第12期1455-1468,共14页
Three-month wind profiles, 260 m PM_1 concentrations [i.e., particulate matter(PM) with an aerodynamic diameter ≤1μm], and carrier-to-noise ratio data at two Beijing sites 55 km apart(urban and suburban) were collec... Three-month wind profiles, 260 m PM_1 concentrations [i.e., particulate matter(PM) with an aerodynamic diameter ≤1μm], and carrier-to-noise ratio data at two Beijing sites 55 km apart(urban and suburban) were collected to analyze the characteristics of low-level nocturnal wind and PM in autumn and winter. Three mountain-plain wind events with wind shear were selected for analysis. The measurements indicated that the maximum wind speeds of the northerly weak low-level jet(LLJ) below 320 m at the suburban site were weaker than those at the urban site, and the LLJ heights and depths at the suburban site were lower than those at the urban site. The nocturnal 140 m mean vertical velocities and the variations in vertical velocity at the urban site were larger than those at the suburban site. A nocturnal breeze with a weak LLJ of ~3 m s^(-1) noticeably offset nocturnal PM transport due to southerly flow and convergence within the northern urban area of Beijing. Characteristics of the nocturnal LLJ, such as start-up time, structure, intensity, and duration, were important factors in determining the decrease in the nocturnal horizontal range and site-based low-level variations in PM. 展开更多
关键词 WEAK low-level jet WIND direction SHEAR WIND lidar low-level PM1
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Clock distribution and local oscillator of a digital low-level radio-frequency board for SSRF 被引量:2
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作者 FU Zechuan ZHAO Yubin +1 位作者 LIU Jianfei ZHAO Zhentang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2010年第1期7-10,共4页
In the storage ring RF system of Shanghai Synchrotron Radiation Facility,the clock distribution and the local oscillator are two parts of the digital low level radio frequency hardware board.In this paper,we designed ... In the storage ring RF system of Shanghai Synchrotron Radiation Facility,the clock distribution and the local oscillator are two parts of the digital low level radio frequency hardware board.In this paper,we designed and produced the clock distribution and the local oscillator board using the AD9858 and AD9510 chips.The results show that the phase noise of the local oscillator signal is lower than 100dBc/Hz with 50 kHz offset. 展开更多
关键词 上海同步辐射装置 时钟分配 本振信号 电路板 射频 本地振荡器 光源 和数
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The Screening of Genes Sensitive to Long-Term, Low-Level Microwave Exposure and Bioinformatic Analysis of Potential Correlations to Learning and Memory 被引量:2
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作者 ZHAO Ya Li LI Ying Xian +6 位作者 MA Hong Bo LI Dong LI Hai Liang JIANG Rui KAN Guang Han YANG Zhen Zhong HUANG Zeng Xin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第8期558-570,共13页
Objective To gain a better understanding of gene expression changes in the brain following microwave exposure in mice. This study hopes to reveal mechanisms contributing to microwave-induced learning and memory dysfun... Objective To gain a better understanding of gene expression changes in the brain following microwave exposure in mice. This study hopes to reveal mechanisms contributing to microwave-induced learning and memory dysfunction. Methods Mice were exposed to whole body 2100 MHz microwaves with specific absorption rates (SARs) of 0.45 W/kg, 1.8 W/kg, and 3.6 W/kg for 1 hour daily for 8 weeks. Differentially expressing genes in the brains were screened using high-density oligonucleotide arrays, with genes showing more significant differences further confirmed by RT-PCR. Results The gene chip results demonstrated that 41 genes (0.45 W/kg group), 29 genes (1.8 W/kg group), and 219 genes (3.6 W/kg group) were differentially expressed. GO analysis revealed that these differentially expressed genes were primarily involved in metabolic processes, cellular metabolic processes, regulation of biological processes, macromolecular metabolic processes, biosynthetic processes, cellular protein metabolic processes, transport, developmental processes, cellular component organization, etc. KEGG pathway analysis showed that these genes are mainly involved in pathways related to ribosome, Alzheimer's disease, Parkinson's disease, long-term potentiation, Huntington's disease, and Neurotrophin signaling. Construction of a protein interaction network identified several important regulatory genes including synbindin (sbdn), Crystallin (CryaB), PPP1CA, Ywhaq, Psap, Psmb1, Pcbp2, etc., which play important roles in the processes of learning and memory. Conclusion Long-term, low-level microwave exposure may inhibit learning and memory by affecting protein and energy metabolic processes and signaling pathways relating to neurological functions or diseases. 展开更多
关键词 LONG-TERM low-level MICROWAVE Gene chip Learning and memory
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Advanced topics on RF amplitude and phase detection for low-level RF systems 被引量:4
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作者 Zhe-Qiao Geng Roger Kalt 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第10期9-20,共12页
Low-level radio frequency(LLRF)systems stabilize the electromagnetic field in the RF cavities used for beam acceleration in particle accelerators.Reliable,accurate,and precise detection of RF amplitude and phase is pa... Low-level radio frequency(LLRF)systems stabilize the electromagnetic field in the RF cavities used for beam acceleration in particle accelerators.Reliable,accurate,and precise detection of RF amplitude and phase is particularly important to achieve high field stability for pulsed accelerators of free-electron lasers(FEL).The digital LLRF systems employ analog-to-digital converters to sample the frequency down-converted RF signal and use digital demodulation algorithms to calculate the RF amplitude and phase.Different sampling strategies and demodulation algorithms have been developed for these purposes and are introduced in this paper.This article focuses on advanced topics concerning RF detection,including accurate RF transient measurement,wideband RF detection,and RF detection with an asynchronous trigger,local oscillator,or clock.The analysis is based on the SwissFEL measurements,but the algorithms introduced are general for RF signal detection in particle accelerators. 展开更多
关键词 low-level RADIO frequency RF detector RF TRANSIENT DETECTION ASYNCHRONOUS RF DETECTION
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Impacts of an Improved Low-Level Cloud Scheme on the Eastern Pacific ITCZ-Cold Tongue Complex 被引量:3
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作者 戴福山 宇如聪 +2 位作者 张学洪 俞永强 李江龙 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第4期559-574,共16页
A statistically-based low-level cloud parameterization scheme is introduced, modified, and applied in the Flexible coupled General Circulation Model (FGCM-O). It is found that the low-level cloud scheme makes improved... A statistically-based low-level cloud parameterization scheme is introduced, modified, and applied in the Flexible coupled General Circulation Model (FGCM-O). It is found that the low-level cloud scheme makes improved simulations of low-level cloud fractions and net surface shortwave radiation fluxes in the subtropical eastern oceans off western coasts in the model. Accompanying the improvement in the net surface shortwave radiation fluxes, the simulated distribution of SSTs is more reasonably asymmetrical about the equator in the tropical eastern Pacific, which suppresses, to some extent, the development of the double ITCZ in the model. Warm SST biases in the ITCZ north of the equator are more realistically reduced, too. But the equatorial cold tongue is strengthened and extends further westward, which reduces the precipitation rate in the western equatorial Pacific but increases it in the ITCZ north of the equator in the far eastern Pacific. It is demonstrated that the low-level cloud-radiation feedback would enhance the cooperative feedback between the equatorial cold tongue and the ITCZ. Based on surface layer heat budget analyses, it is demonstrated that the reduction of SSTs is attributed to both the thermodynamic cooling process modified by the increase of cloud fractions and the oceanic dynamical cooling processes associated with the strengthened surface wind in the eastern equatorial Pacific, but it is mainly attributed to oceanic dynamical cooling processes associated with the strengthening of surface wind in the central and western equatorial Pacific. 展开更多
关键词 parameterization low-level cloud double ITCZ equatorial cold tongue coupled model
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Kinetics of low level chemiluminescence from plant leaf smoked by air pollutants
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作者 Wang Ying yan, Wang Jin guang Beijing Municipal Research Institute of Environmental Protection,Beijing 100037,China Ma Yu qin, Su Zhen, Zhao Kai jian, Zhang Zhong lun, Zheng Yan zhen, Liu Cheng xian Institute of Biophysics,Chinese Academy of Scie 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第1期45-50,共6页
The kinetics of low level chemiluminescence from Chinese white polpar leaf smoked by CO and two gaseous mixture of SO 2 and CO or SO 2, NO x and CO, and their luminescence intensity formula were described. The compa... The kinetics of low level chemiluminescence from Chinese white polpar leaf smoked by CO and two gaseous mixture of SO 2 and CO or SO 2, NO x and CO, and their luminescence intensity formula were described. The comparison of the results indicated that three kinds of the gaseous compounds could cause no changes of the substantial nature of foliar biophoton emission. However, they made the luminescence intensity, including I o (1) and I o (2) , altered in a certain degree, and the changes caused by the fumigation of CO and the mixed gas of SO 2 and CO were different from that made by the gaseous mixture of SO 2, NO x and CO in τ′ and τ″ of the photo induced luminescence from plant leaf. 展开更多
关键词 KINETICS low level chemiluminescence plant leaf air pollutants.
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The Impact of Low-Level Cloud over the Eastern Subtropical Pacific on the "Double ITCZ" in LASG FGCM-0 被引量:1
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作者 戴福山 宇如聪 +2 位作者 张学洪 俞永强 李江龙 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第3期461-474,共14页
Like many other coupled models, the Flexible coupled General Circulation Model (FGCM-0) suffers from the spurious “Double ITCZ”. In order to understand the “Double ITCZ” in FGCM-0, this study first examines the lo... Like many other coupled models, the Flexible coupled General Circulation Model (FGCM-0) suffers from the spurious “Double ITCZ”. In order to understand the “Double ITCZ” in FGCM-0, this study first examines the low-level cloud cover and the bulk stability of the low troposphere over the eastern subtropical Pacific simulated by the National Center for Atmospheric Research (NCAR) Community Climate Model version 3 (CCM3), which is the atmosphere component model of FGCM-0. It is found that the bulk stability of the low troposphere simulated by CCM3 is very consistent with the one derived from the National Center for Environmental Prediction (NCEP) reanalysis, but the simulated low-level cloud cover is much less than that derived from the International Satellite Cloud Climatology Project (ISCCP) D2 data. Based on the regression equations between the low-level cloud cover from the ISCCP data and the bulk stability of the low troposphere derived from the NCEP reanalysis, the parameterization scheme of low-level cloud in CCM3 is modified and used in sensitivity experiments to examine the impact of low-level cloud over the eastern subtropical Pacific on the spurious “Double ITCZ” in FGCM-0. Results show that the modified scheme causes the simulated low-level cloud cover to be improved locally over the cold oceans. Increasing the low-level cloud cover off Peru not only significantly alleviates the SST warm biases in the southeastern tropical Pacific, but also causes the equatorial cold tongue to be strengthened and to extend further west. Increasing the low-level cloud fraction off California effectively reduces the SST warm biases in ITCZ north of the equator. In order to examine the feedback between the SST and low-level cloud cover off Peru, one additional sensitivity experiment is performed in which the SST over the cold ocean off Peru is restored. It shows that decreasing the SST results in similar impacts over the wide regions from the southeastern tropical Pacific northwestwards to the western/central equatorial Pacific as increasing the low-level cloud cover does. 展开更多
关键词 coupled model double ITCZ low-level cloud
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