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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第4期14卷 288-295页

作者： Ge-liang YANG Zhi-gong WANG Zhi-qun LI Qin LI fa-en LIU Zhu LI Engineering research Center of rF-ICs and rF-Systems Ministry of EducationSoutheast University

A Ka-band sub-harmonically pumped resistive mixer(SHPrm) was designed and fa.ricated using the standard 0.18-μm complementary metal-oxide-semiconductor(CmOS) *** area-effective asymmetric broadside coupled spiral marchand balance-to-unbalance(balun) with magnitude and phase imbalance compensation is used in the mixer to transform.local oscillation(lo) signal from single to differential *** results showed that the SHPrm achieves the conversion gain of-15--12.5 dB at fixed fIF=0.5 GHz with 8 dBm.lo input power for the radio frequency(rF) bandwidth of 28-35 *** in-band lo-intermediate freqency(IF),rF-IF,and lo-rF isolations are better than 31,34,and 36 dB,***,the 2lo-IF and 2lo-rF isolations are better than 60 and 45 dB,*** measured input referred P1dB and 3rd-order inter-modulation intercept point(IIP3) are 0.5 and 10.5 dBm,*** measurement is performed under a gate bias voltage as low as 0.1 V and the whole chip only occupies an area of 0.33 mm2 including pads.

关键词： CmOS技术宽边耦合 Ka波段混频器次谐波超低电压微米巴伦

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自动补偿温漂的直流放大器

宇航计测技术 1989年第6期8卷 75-77页

作者： r.C.S.freire m.Abignoli A.m.N.Lima G.S.deep 阎军

本文介绍了一种用普通运放构成的自动补偿温漂的直流应变电桥放大电路。放大器的工作分两步,一是自动补偿,二是放大输入信号。输入补偿是通过开关使电桥的激励源周期切换到零电位实现的,切换频率约为100Hz。因此,限定输入信号的最高频率... 详细信息

本文介绍了一种用普通运放构成的自动补偿温漂的直流应变电桥放大电路。放大器的工作分两步,一是自动补偿,二是放大输入信号。输入补偿是通过开关使电桥的激励源周期切换到零电位实现的,切换频率约为100Hz。因此,限定输入信号的最高频率为8Hz。放大器的增益为5000,当温度变化40℃时,测得输出电压漂移约1mV。

关键词：直流放大器自动补偿温漂

On-chip generation of Bessel–Gaussian beam via concentrically distributed grating arrays for long-range sensing

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Light(Science & Applications) 2023年第5期12卷 817-825页

作者： Zihao Zhi Quanxin Na Qijie Xie Baisong Chen Yingzhi Li Xiaobin Liu Xuetong Li Lijun Wang Guoqiang lo Junfeng Song State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China Peng Cheng Laboratory Shenzhen 518000China State Key Laboratory of Luminescence and Application Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Advance micro Foundry Pte.Ltd. 11 Science Park RoadScience Park II 117685Singapore

Bessel beam featured with self-healing is essential to the optical sensing applications in the obstacle scattering *** on-chip generation of the Bessel beam outperforms the conventional structure by small size,robustness,and alignment-free ***,the maximum propagation distance(Z_(max))provided by the existing approaches cannot support long-range sensing,and thus,it restricts its potential *** this work,we propose an integrated silicon photonic chip with unique structures featured with concentrically distributed grating arrays to generate the Bessel-Gaussian beam with a long propagation *** spot with the Bessel function profile is measured at 10.24m without optical lenses,and the photonic chip’s operation wavelength can be continuously performed from 1500 to 1630 *** demonstrate the functionality of the generated Bessel-Gaussian beam,we also experimentally measure the rotation speeds of a spinning object via the rotational Doppler Effect and the distance through the phase laser ranging *** maximum error of the rotation speed in this experiment is measured to be 0.05%,indicating the minimum error in the current *** the compact size,low cost,and mass production potential of the integrated process,our approach is promising to readily enable the Bessel-Gaussian beam in widespread optical communication and micro-manipulation applications.

关键词： scattering Bessel beam

New Formulation for Semi-Empirical Correlations for Penetration Jets

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World Journal of Nuclear Science and Technology 2019年第2期9卷 96-111页

作者： r. r. Pacheco L. O. freire m. S. rocha N. L. Scuro m. O. menezes D. A. Andrade Centro Tecnológico da marinha em S&atilde o Paulo S&atilde o Paulo Brazil Instituto de Pesquisas Energéticas e Nucleares S&atilde o Paulo Brazil

Correlations for the extension of a water vapor jet injected in a liquid pool were historically proposed considering the mass flux (kg/m2/s) as a constant. The results were satisfactory, however adjusting the values by linear regression. Although, it presents the following drawbacks: 1) the formulation is only valid for the specific range of data for what it was created;2) it does not allow the analytical evaluation of the heat transfer coefficient from the extension equation. This paper proposes a new formulation for the calculation of the mass flux, in such a way to remove both of these drawbacks.

关键词： Direct Contact Condensation Vapor Jet Steam Jet Steam mass Flux Vapor Cavity reynolds Number Jet radius rate of Condensation Non-Dimensional Jet Length Liquid Pool Dimensionless Transport modulus Condensation Driving Potential

Hypertension and Work Stress among City Hall Workers, Bohicon, Benin

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Occupational Diseases and Environmental medicine 2022年第2期10卷 102-115页

作者： mênonli Adjobimey rose mikponhoué Djohoun F. Frimège Ibrahim mama Cissé Concheta Tchibozo Esdras Hountohotegbe Hélène Sacca Paul Ayélo Vikkey Antoine Hinson Dismand Houinato research and Teaching Unit in Occupational and Environmental Health FSS Cotonou Benin Service of the National University Hospital of Pneumo-Phtisiology of Cotonou Cotonou Benin Laboratory of Epidemiology of Chronic and Neurological Diseases FSS Cotonou Benin School of medicine University of Parakou Parakou Benin

Introduction: In the general population as well as in the workplace, hypertension is one of the main causes of morbidity and mortality in the world. The particularities of hypertension in the world of work remain little studied. The objective of this study was to determine the prevalence and factors associated with hypertension among workers in a town hall in Benin in 2019. methods: This was a descriptive, analytical cross-sectional study conducted from december 2018 to January 2019. A comprehensive recruitment was conducted. Data were collected during a face-to-face interview, supplemented by measurement of anthropometric parameters and blood pressure as well as a work stress assessment. Frequencies were compared using the chi-square test and Fisher’s test. The significance level was 5%. results: A total of 86 workers were included. Their mean age was 41.55 ± 9.82 years with a sex ratio of 6.1. The prevalence of hypertension was estimated to be 18.6% [95% CI: 11.96% - 29.75%]. Hypertension was higher in workers under work stress (41.18%) as opposed to non-stressed workers (14.49%) (p = 0.032);in those who were overweight (30.77) as opposed to non-overweight (2.94%) (p Conclusion: Work stress and obesity are modifiable factors associated with hypertension in workers at the Bohicon city hall. These factors deserve to be corrected by occupational health promotion and prevention actions.

关键词： Hypertension Stress Overweight Workers Benin

Line profile analysis of an astronomical spectrograph with a laser frequency comb

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research in Astronomy and Astrophysics 2014年第8期14卷 1037-1045页

作者： Fei Zhao Gang Zhao Gaspare lo Curto Hui-Juan Wang Yu-Juan Liu Liang Wang Wei Wang Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences University of Chinese Academy of Sciences Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsShandong University European Southern Observatory Karl-Schwarzschild-Str. 285748 GarchingGermany

We present a study of the spectral line shape associated with a High resolution Spectrograph on the 2.16 m telescope at the Xinglong Observing Station of National Astronomical Observatories, Chinese Academy of Sciences. This measurement is based on modeling the instrumental line shape obtained by unresolved modes from a Yb-fiber mode-locked laser frequency comb. With the current repetition rate of 250 mHz and 26 GHz mode spacing on the spectrograph, we find the absolute variation of the line center, 0.0597 pixel in the direction of the CCDs, and 0.00275 pixel （～3 m s^-1） for relative variation in successive exposures on a short timescale. A novel double-Gaussian model is presented to improve the quality of the fit by a factor of 2.47 in a typical single exposure. We also use analysis with raw moments and central moments to characterize the change in line shape across the detector. A trend in charge transfer efficiency can be found on the E2V 4096 ×4096 CCD that provides a correction for wavelength calibration aiming to reach a level of precision for radial velocity below 1 m s^- 1.

关键词： techniques radial velocities -- instrumentation laser frequency comb

Epstein-Barr virus infection and persistence in nasopharyngeal epithelial cells

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Chinese Journal of Cancer 2014年第11期33卷 549-555页

作者： Chi man Tsang Wen deng Yim Ling Yip mu-Sheng Zeng Kwok Wai lo Sai Wah Tsao department of Anatomy Li Ka Shing Faculty of MedicineThe University of Hong Kong School of Nursing Li Ka Shing Faculty of MedicineThe University of Hong Kong State Key Laboratory of Oncology in South China Sun Yat-sen University Cancer Center department of Anatomical and Cellular Pathology The Chinese University of Hong Kong

Epstein-Barr virus(EBV) infection is closely associated with undifferentiated nasopharyngeal carcinoma(NPC), strongly implicating a role for EBV in NPC pathogenesis; conversely, EBV infection is rarely detected in normal nasopharyngeal epithelial tissues. In general, EBV does not show a strong tropism for infecting human epithelial cells, and EBV infection in oropharyngeal epithelial cells is believed to be lytic in nature. To establish life-long infection in humans, EBV has evolved efficient strategies to infect B cells and hijack their cellular machinery for latent infection. Lytic EBV infection in oropharyngeal epithelial cells, though an infrequent event, is believed to be a major source of infectious EBV particles for salivary transmission. The biological events associated with nasopharyngeal epithelial cells are only beginning to be understood with the advancement of EBV infection methods and the availability of nasopharyngeal epithelial cell models for EBV infection studies. EBV infection in human epithelial cells is a highly inefficient process compared to that in B cells, which express the complement receptor type 2(Cr2) to mediate EBV infection. Although receptor(s) on the epithelial cell surface for EBV infection remain(s) to be identified, EBV infection in epithelial cells could be achieved via the interaction of glycoproteins on the viral envelope with surface integrins on epithelial cells, which might trigger membrane fusion to internalize EBV in cells. Normal nasopharyngeal epithelial cells are not permissive for latent EBV infection, and EBV infection in normal nasopharyngeal epithelial cells usually results in growth arrest. However, genetic alterations in premalignant nasopharyngeal epithelial cells, including p16 deletion and cyclin D1 overexpression, could override the growth inhibitory effect of EBV infection to support stable and latent EBV infection in nasopharyngeal epithelial cells. The EBV episome in NPC is clonal in nature, suggesting that

关键词：病毒感染上皮细胞鼻咽癌持久性细胞周期蛋白D1 全国人民代表大会生长抑制作用 EB病毒

Effects of Light Emitting Diode in Erythrocytes

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modern research in Inflammation 2014年第3期3卷 122-127页

作者： Hennes Gentil de Araújo Patricia Froes meyer mario Bernardo Filho Eric Heleno freire Frederico Sebastiao David dos Santos Filho marcus Vinicius de mello Pinto Universidade Federal do rio Grande do Norte(UFrN) NatalBrazil Universidade Federal do rio de Janeiro(UFrJ) Rio de JaneiroBrazil Universidade Estadual do rio de Janeiro(UErJ) Rio de JaneiroBrazil Instituto Celulare Centro de Tratamento a Laser e Terapia CelularRio de JaneiroBrazil

The Light Emitting Diode (LED) is a phototherapy equipment, poorly studied, which is able of acting on blood level and it has frequently appeared in clinical practice of physiotherapy to aid on skin rejuvenation, control inflammation and wound healing. The aim of the study was to evaluate the effects of LED on red blood cells through the spectrophotometer. This is an experimental study with a sample of 5 male Wistar rats weighting between 200 g and 350 g, randomly selected, anesthetized and 4 ml of blood was collected by cardiac puncture. The blood collected was divided into four groups, one control and three treated, these individually irradiated by blue LED (420 - 490 nm), green LED (515 - 570 nm) and red LED (620 - 680 nm) at an output of 3 watts, for 10 minutes and 5 cm apart from the surface of the blood, then it was analyzed by a spectrophotometer at 540 nm. The results were submitted to Anova and Post-roch Turkey (p roduced hemolysis greater than the control in hypotonic solutions of NaCl (range 0.02 to 0.06 m) (p m provides a higher hemolysis (range 0.06 to 0.1) when compared to the control group (p rradiation of blood through the LED therapy was able to weaken the cell membrane of the red blood cells. It is likely that hemolysis does not bring harm the body, because as it is a local therapy, the amount of hemolysis that can be caused is small and it will induce the reproduction of new red blood cells, thus improving their physiological functions.

关键词： LED Blood Spectrophotometer

Chronic myeloid leukemia-from the Philadelphia chromosome to specific target drugs:A literature review

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World Journal of Clinical Oncology 2021年第2期12卷 69-94页

作者： mariana miranda Sampaio maria Luísa Cordeiro Santos Hanna Santos marques Vinícius Lima de Souza Gonçalves Glauber rocha Lima Araújo Luana Weber lopes Jonathan Santos Apolonio Cam.lo Santana Silva Luana Kauany de SáSantos Beatriz rocha Cuzzuol Quézia Estéfani Silva Guimarães mariana Novaes Santos Breno Bittencourt de Brito Filipe Antônio França da Silva márcio Vasconcelos Oliveira Cláudio Lima Souza fa.rício freire de m.lo Instituto multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil Campus Vitória da Conquista Universidade Estadual do Sudoeste da BahiaVitória da Conquista 45083-900BahiaBrazil

Chronic myeloid leukemia(CmL)is a myeloproliferative neoplasm and was the first neoplastic disease associated with a well-defined genotypic anomaly―the presence of the Philadelphia *** advances in cytogenetic and molecular assays are of great importance to the diagnosis,prognosis,treatment,and monitoring of *** discovery of the breakpoint cluster region(BCr)-Abelson murine leukemia(ABL)1 fusion oncogene has revolutionized the treatment of CmL patients by allowing the development of targeted drugs that inhibit the tyrosine kinase activity of the BCr-ABL *** kinase inhibitors(known as TKIs)are the standard therapy for CmL and greatly increase the survival rates,despite adverse effects and the odds of residual disease after discontinuation of *** therapeutic alternatives,the subsequent TKIs lead to faster and deeper molecular remissions;however,with the emergence of resistance to these drugs,immunotherapy appears as an alternative,which may have a cure potential in these *** this background,this article aims at providing an overview on CmL clinical management and a summary on the main targeted drugs available in that context.

关键词： Chronic myeloid leukemia Breakpoint cluster region-Abelson murine leukemia Immunotherapy Tyrosine kinase inhibitors Philadelphia chromosome Diagnosis

delivery of therapeutics to posterior eye segment:cell-encapsulating systems

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Neural regeneration research 2017年第4期12卷 576-577页

作者： francisca s.y.wong ken k.tsang amy c.y.lo department of ophthalm.logy li ka shing faculty of medicinethe university of hong kongHong Kong Special Administrative RegionChina research center of heart brainhormone and healthy agingli ka shing faculty of medicinethe university of hong kongHong Kong Special Administrative RegionChina

Drug delivery to the posterior segment of the eye, especially the retina, faces the unique challenges of various anatomical and physiological barriers. Invasive intravitreal injection is currently the mainstream clinical approach to posterior eye diseases such as age-related macular degeneration, diabetic retinopathy, uveitis, and cytomegalovirus retinitis. repeated injections could be complicated by endophthalmitis, intra- ocular pressure elevation, retinal vascular occlusion, and ret- inal detachment, let alone the psychological and economical burdens suffered by patients （Schwartz et al., 2014）. In view of this, several extended release drug delivery systems have been devised and the idea of encapsulated-cell technology （ECT） has gained popularity in recent decades since its first proposal in the 1960s.

关键词： cell-encapsulating systems delivery of therapeutics to posterior eye segment