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A NEW cumulus PARAMETERIZATION SCHEME AND ITS APPLICATION TO PRECIPITATION NUMERICAL PREDICTION

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Science China Chemistry 1991年第7期34卷 883-896页

作者：许习华丁一汇 National Research Center for Marine Environment Forecasts Beijing 100081 PRC Academy of Meteorological Sciences SMA Beijing 100081 PRC

According to the characteristics of cumulus and stratiform clouds during the meiyu period (plum rains) over Jianghuai valleys (the Changjiang (Yangtze) River and the Huaihe River), a modified Kuo-type cumulus parameterization scheme applicable to midlatitude con-vective systems is suggested in this paper. It is often observed that cumulus and stratiform clouds coexist in a rain-bearing synoptic systems and the precipitation amount associated with this system may be amplified by their interaction. With some important processes of cloud physics taken into account, we use a simple seeder-feeder model (including colloidal instability, collision effect and entrainment) to describe this process of interaction within framework of Kuo-type cumulus parameterization. It is found that the rainfall amount caused by ice crystal effect accounts for 30-40% of total rainfall, but the collision effect is not so great generally. We introduced this scheme to the regional numerical model used by Wuhan Observatory of Hubei Meteorological Service to make tests of its performance. With six experiments of prediction of precipitation during the meiyu period, the results are very encouraging, especially good in the cases of coexistence of cumulus and stratiform clouds.

关键词： cumulus parameterization interaction of cumulus and stratiform cloud precipitation prediction.

Forecasts of MJO Events during DYNAMO with a Coupled Atmosphere–Ocean Model:Sensitivity to cumulus Parameterization Scheme

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Journal of Meteorological Research 2019年第6期33卷 1016-1030页

作者： Mei-Yu CHANG Tim LI Pay-Liam LIN Ting-Huai CHANG Institute of Atmospheric Physics Department of Atmospheric Sciences“National”Central UniversityTaoyuan 32001 Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044 Department of Earth and Life Science University of TaipeiTaipei 10048 Central Weather Bureau(CWB) Taipei 10048

An operational weather forecast model,coupled to an oceanic model,was used to predict the initiation and propagation of two major Madden–Julian Oscillation(MJO)events during the dynamics of the MJO(DYNAMO)campaign *** convective parameterization schemes were used to understand the sensitivity of the forecast to the model cumulus *** first is the Tiedtke(TDK)scheme,and the second is the Simplified Arakawa–Schubert(SAS)*** TDK scheme was able to forecast the MJO-1 and MJO-2 initiation at 15-and45-day lead,respectively,while the SAS scheme failed to predict the convection onset in the western equatorial Indian Ocean(WEIO).The diagnosis of the forecast results indicates that the successful prediction with the TDK scheme is attributed to the model capability to reproduce the observed intraseasonal outgoing longwave radiation–sea surface temperature(OLR–SST)*** one hand,the SST anomaly(SSTA)over the WEIO was induced by surface heat flux anomalies associated with the preceding suppressed-phase *** change of SSTA,in turn,caused boundary layer convergence and ascending motion,which further induced a positive column-integrated moist static energy(MSE)tendency,setting up a convectively unstable stratification for MJO *** forecast with the SAS scheme failed to reproduce the observed OLR–SST–MSE *** propagation characteristics differed markedly between the two *** eastward phase propagation in the TDK scheme is attributed to a positive zonal gradient of the MSE tendency relative to the MJO center,similar to the observed,whereas a reversed gradient appeared in the forecast with the SAS scheme with dominant westward *** difference is primarily attributed to anomalous vertical and horizontal MSE advection.

关键词： Madden–Julian Oscillation(MJO) initiation and eastward propagation dynamics of the MJO(DYNAMO) cumulus parameterization scheme moist static energy(MSE)budget

Sources of cumulus expansion enabling factor (CEEF) in porcine follicles

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Chinese Science Bulletin 2002年第19期47卷 1619-1622页

作者： SUN Xingshen YUE Kuizhong MA Suofeng YI Yaling ZOU Yi TAN Jinghe Faculty of Life Sciences Northeast Agricultural UniversityHarbin 150030China College of Animal and Veterinary Science Shandong Agricultural UniversityTai’an 271018China

It was shown that expansion of porcine cumulus did not depend on oocyte-secreted factor(s), and it is therefore presumed that porcine CEEF may not be produced exclusively by the oocyte. In this experiment, we used mouse oocytectomized complexes (OOX), which were incapable of CEEF production, to assess the secretion of CEEF by evacuated zona, oocytes of different quality and somatic cells in the porcine follicles. The results showed that: (i) Evacuated zonae from both porcine and mouse oocytes did not produce CEEF. (ii) Porcine oocytes of A, B and C types from 3-6 mm follicles were not significantly different in both production and activity of CEEF. (iii) Both porcine OOX from 3-6 mm follicles and granulose cells from < 1 mm follicles secreted CEEF in a large quantity, independent of gonadotro-pins; mural granulose cells from 3-6 mm follicles, however, produced neglectable amount of CEEF. (iv) The follicular fluid from 3-6 mm porcine follicles contained CEEF activity that was concentration-dependent,

关键词： cumulus expansion enabling factor cumulus expansion follicle oocyte porcine.

A MODIFIED cumulus PARAMETERIZATION SCHEME AND ITS APPLICATION IN THE SIMULATIONS OF THE HEAVY PRECIPITATION CASES

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Journal of Tropical Meteorology 2016年第3期22卷 433-444页

作者：平凡唐细坝殷蕾 Laboratory of Cloud-Precipitation Physics and Severe Storms(LACS) Institute of Atmospheric Physics Department of Remote Sensing Nanjing University of Information Science and Technology

According to the characteristics of organized cumulus convective precipitation in China,a cumulus parameterization scheme suitable for describing the organized convective precipitation in East Asia is presented and *** Kain-Fristch scheme is chosen as the scheme to be modified based on analyses and comparisons of simulated precipitation in East Asia by several commonly-used mesoscale parameterization schemes.A key dynamic parameter to dynamically control the cumulus parameterization is then proposed to improve the Kain-Fristch *** simulations of a typhoon case and a Mei-yu front rainfall case are carried out with the improved scheme,and the results show that the improved version performs better than the original in simulating the track and intensity of the typhoons,as well as the distribution of Mei-yu front precipitation.

关键词： cumulus parameterization scheme organized convection Kain-Fristch scheme precipitation simulation

Microphysical characteristics of precipitating cumulus cloud based on airborne Ka-band cloud radar and droplet measurements

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Atmospheric and Oceanic Science Letters 2022年第2期15卷 65-70页

作者： Lei Wei Mengyu Huang Rong Zhang Yuhuan Lü Tuanjie Hou Hengchi Lei Delong Zhao Wei Zhou Yuan Fu Beijing Weather Modification Center BeijingChina Key Laboratory for Cloud Physics of China Meteorological Administration BeijingChina Wuqing Meteorological Observatory of Tianjin TianjinChina Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Zhejiang Meteorological Observatory HangzhouChina Beijing Key Laboratory of Cloud Precipitation and Atmospheric Water ResourcesBeijingChina Beijing Meteorological Bureau BeijingChina

Based on cloud-probe data and airborne Ka-band cloud radar data collected in Baoding on 5 August 2018,the microphysical structural characteristics of cumulus(Cu)cloud at the precipitation stage were *** cloud droplets in the Cu cloud were found to be significantly larger than those in stratiform(STF)*** the Cu cloud,most cloud particles were between 7 and 10μm in diameter,while in the STF cloud the majority of cloud particles grew no larger than 2μ*** sensitivity of cloud properties to aerosols varied with *** cloud droplet effective radius showed a negative relationship with the aerosol number concentration(Na)in the cloud planetary boundary layer(PBL)and upper layer above the ***,the cloud droplet concentration(Nc)varied little with decreased Na in the high liquid water content region above 1500 *** Na values of between 300 and 1853 cm-3 were found in the PBL,and the maximum Na was sampled near the surface in August in the Hebei region,which was lower than that in autumn and *** radar reflectivity corresponded to large FCDP(fast cloud droplet probe)particle concentrations and small aerosol particle concentrations,and vice versa for low radar *** updrafts in the Cu cloud increased the peak radius and Nc,and broadened cloud droplet spectrum;lower air temperature was favorable for particle condensational growth and produced larger droplets.

关键词： Airplane observation Microphysical processes Ka-band cloud radar cumulus

Effect of exogenous progesterone on cumulus characteristics of buffalo oocytes by allowing passage of more number of sperm through cumulus but not essentially fertilization

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Asian pacific Journal of Reproduction 2018年第2期7卷 79-86页

作者： Madhusmita Panda Asmita Sandeep Kumar Purusottam Mishra Mahesh Chandra Sahu Sachinandan De Tirtha Kumar Datta Rakesh Kumar Nodal Officer Chief District Veterinary OfficeKadambedaBhadrak756100OdishaIndia Institute of Microbial Technology Council of Scientific and Industrial ResearchChandigarhIndia BSL-4 National Institute of VirologySus RoadPashanPune-411021India Goat Breeding Farm AT/PO-SalapadaDistrict-KeonjharPin code-758020State-OdishaIndia Directorate of Medical Research IMS and SUM HospitalSiksha'O'Anusandhan UniversityK8Kalinga NagarBhubaneswar-751003OdishaIndia Animal Biotechnology Centre National Dairy Research InstituteKarnal132001HaryanaIndia

Objective:To understand the level of progesterone (P4) in different quality of buffalo cumulus oocyte complexes (COCs) and further to evaluate the effect of exogenous P4 supplementation on maturation and subsequent developmental ability of poor quality brilliant cresyl blue (BCB-)***: Progesterone secreted by different quality of buffalo oocytes was estimated by enzyme linked immunosorbent assay and the concentration differences were translated into P4 doses to be incorporated in the maturation medium of BCB-ve COCs followed by expression analysis of genes involved in the cumulus expansion, extracellular matrix disintegration and progesterone receptor signalling. In addition, the study also evaluated the effect of exogenous P4 on sperm-cumulus interaction. Results: More than 10-fold up-regulated expression of progesterone receptor in P4 supplemented oocytes signified that P4 might be acting predominantly through this receptor. Also, exogenous P4 supplementation had significant effect on transcatheter arterial chemoembolization protease regulated by P4-progesterone receptor pathway which in turn had an important role in extracellular matrix disintegration. On the contrary, cumulus expansion genesHAS2,TNFAIP6,AREG were not altered upon P4 supplementation. Also, it was observed that P4 addition did facilitate passage of significantly more number of spermatozoa through P4 treated cumulus cells. Further, incorporation of different doses of P4 did not improve significantly the cleavage and blastocyst rates of BCB-ve ***: Different qualities of buffalo COCs secrete substantially diverse levels of P4, and its supplementation has a role in oocyte maturation via modulation of cumulus characteristics but perhaps not fertilization.

关键词： BCB screening Progesterone Sperm cumulus interaction Fertilizing ability

The Impact of cumulus Parameterization on Rainfall Simulations over East Africa

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Atmospheric and Climate Sciences 2018年第3期8卷 355-371页

作者： G. Otieno J. Mutemi F. Opijah L. Ogallo H. Omondi University of Nairobi Department of Meteorology Nairobi Kenya IGAD Climate Prediction and Application Centre Nairobi Kenya

The study explored the ability of four cumulus parameterization schemes (CPSs) from Weather and Research Forecasting model (WRF) to simulate mean rainfall patterns, number of rainy days (NRD) and vertically integrated moisture flux (VIMF) during the composite of wet years for the core rainfall seasons of March-April-May (MAM;1989, 1998 and 2012) and Octo-ber-November-December (OND;1997, 2006 and 2015) seasons. The CPSs used were Kain-Fritsch (KF), Kain-Fritsch with a moisture-advection based trigger function (KFT), Grell Dévényi (GRELL) and Betts Miller Janjic (BML). The simulations by the GRELL and KF schemes were clearly separated by the dry and wet rainfall gradient in the simulations. For example, the GRELL scheme rainfall simulations were drier over the eastern parts of the region bet-ter. The KF and KFT schemes generated wetter rainfall conditions mainly con-fined to the western parts of the region. The BML scheme simulations were not consistent with the observations. The western and eastern parts of the region were characterized by more and fewer NRD, in both the KF and GRELL schemes. The root mean square error (RMSE) and spatial correlation by KF scheme was 2 mm/day and 0.6. The GRELL scheme however simulated low correlation of 0.45 and RMSE of about 3.0 mm/day over most of the sub-domains. The moisture convergence biases were found to be larger conti-nentally and parts of the nearby Indian Ocean. The persisting rainfall biases constituting of too wet and dry conditions were associated with the KF and GRELL cumulus schemes. The findings from the current study are very funda-mental for the improvement of numerical weather prediction (NWP) tools and cumulus modification processes over the region. The accurate and higher skill rainfall forecasts would provide early warning information for disaster risk re-duction and the related risks on the livelihoods.

关键词： Rainfall Characteristics cumulus Schemes East Africa

Cloned calves produced by nuclear transfer from cultured cumulus cells

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Science China(Life Sciences) 2002年第2期45卷 201-210页

作者：安晓荣关宏曾申明苟克勉侯健田见辉林爱星朱士恩陈永福 State Key Laboratory for Agrobiotechnologies China Agricultural University Beijing 100094 China College of Animal Sciences and Technologies China Agricultural University Beijing 100094 China

Short-term cultured cumulus cell lines (1-5BCC) derived from 5 individual cows were used in nuclear transfer (NT) and 1188 enucleated bovine oocytes matured in vitro were used as nuclear recipients. A total of 931 (78.4%) cloned embryos were reconstructed, of which 763 (82%) cleaved, 627 (67.3%) developed to 8-cell stage, and 275 (29.5%) reached blastocyst stage. The average cell number of blastocysts was 124±24.5 (n=20). In this study, the effects of donor cell sources, serum starvation of donor cells, time interval from fusion to activation (IFA) were also tested on cloning efficiency. These results showed that blastocyst rates of embryos reconstructed from 5 different individuals cells were significantly different among them (14.1%, 45.2%, 27.3%, 34.3%, vs 1.5%, P0.05); and that blastocyst rate (20.3%) of the group with fusion/activation interval of 2-3 h, was significantly lower than that of the 3-6 h groups (31.0%), while not significantly different among 3-4 h (P cumulus cells is not a key factor for successful bovine cloning, while IFA treatment and sources of donor cells have effects on cloning efficiency.

关键词： cumulus cell, nuclear transfer, embryo freezing, cloned calf.

Effect of cumulus Cells on the Efficiency of Vitrified-Thawed Immature Cattle Oocytes

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Open Journal of Obstetrics and Gynecology 2019年第5期9卷 669-678页

作者： Samia Mohamed Abd-El Rheem Suzan Elsharkawy Theriogenology Department Faculty of Veterinary Medicine Alexandria University Alexandria Egypt Gynecology and Obstetrics Department Faculty of Medicine Alexandria University Alexandria Egypt

The present work was designed to examine the effect of the presence or absence of cumulus cells on the efficiency of vitrification of immature cattle oocytes. In our experiment, we had two groups: group 1, immature cattle oocytes with cumulus cells and group 2, immature cattle oocytes without cumulus cells. The two groups underwent vitrification using 20% ethylene glycol and 20% DMSO, and then thawed, and in vitro matured in TCM-199 medium and examined after 22 hours for assessment of nuclear maturation. Higher survival rate (p cumulus cells are very important in increasing the survivability and developmental rate of vitrified-thawed immature cattle oocytes.

关键词： cumulus Cells Vitrified-Thawed Immature Oocytes Cattle