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Asian Journal of Andrology 2005年第4期7卷 411-417,页

作者： paul f.moundipa Nathalie Sara E.Beboy fabien Zelefack Silvère Ngouela Etienne Tsamo Wolf-Bernhard Schill Thomas K.Monsees Departments of Biochemistry Organic Chemistry University of Yaounde IP.O.Box 812 YaoundeCameroon Centre for Dermatology and Andrology Justus Liebig UniversityGaffkystr.1435385 GiessenGermany Centre for Dermatology and Andrology Justus Liebig UniversityGaffkystr.1435385 GiessenGermany Department of AnatomyUniversity of TechnologyFetscherstr.7401307 DresdenGermany

Aim： To determine the androgenic effects of Basella alba and Hibiscus macranthus extracts in the rat and the bull, and to develop a novel in vitro test system using Leydig cells from bull testes. Methods： The effect of methanol extracts from both plants on testosterone production in isolated Leydig cells from the rat and the bull was analyzed using ^125I-radioimmunoassay （^125I-RIA）. Rat Leydig cells were obtained by common methods, whereas a novel technique was used to purify Leydig cells from bull testes. Results： Bull testes from the slaughter house were a cheap source of pure Leydig cells. In culture, these cells produced testosterone for 5-6 days, which can be stimulated by human chorionic gonadotrophin （hCG）. Basella alba extracts significantly enhanced testosterone production in bull and rat Leydig cells in a concentration-dependent manner. Hibiscus macranthus showed no androgenic effect but was shown to inhibit testosterone production at higher concentrations. Conclusion： Leydig cells purified from bull testes can be used as an alternative tool in experimental animal research. Certain fractions of Basella alba extract demonstrated androgenic potential whereas Hibiscus macranthus extracts did not.

关键词： bull rats Leydig cells testosterone Basella alba Hibiscus macranthus plant extract

Androgenic effect of Mondia whitei roots in male rats

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Asian Journal of Andrology 2004年第3期6卷 269-272页

作者： Pierre Watcho Pierre Kamtchouing Selestin D.Sokeng paul f.moundipa Justine Tantchou Jean L.Essame Noussithe Koueta Animal Physiology and Phytopharmacology Laboratory Faculty of ScienceUniversity of DschangDschangCameroon Animal Physiology Laboratory University of Yaounde IYaoundeCameroon Department of Biochemistry Faculty of SciencesUniversity of Yaounde IYaoundeCameroon 不详 University Hospital Centre YaoundeCameroon

Aim: To determine the effect of the aqueous extract of Mondia whitei (Periplocaceae) roots on testosterone production and fertility of male rats. Methods: Adult male Wistar rats were used. In the acute study, 20 rats were randomly divided into 5 groups of 4 animals each. four treated groups were administered orally a single dose of Mondia whitei (400 mg/kg) and the controls received a similar amount of distilled water. One group of animals were sacrificed by cervical dislocation 1,2,4 and 6 h after treatment, respectively. The controls were sacrificed at 6 h. Testicular testosterone was determined by radioimmunoassay. In the chronic study, 28 rats were divided at random into 4 groups of 7 animals each: Groups 1, 2 and 3 were given orally the plant extract (400 mg·kg-1·day-1) for 2, 4 and 8 days, respectively. The animals of Groups 1 and 2 were sacrificed 24 hours after the last dosing. The controls (Group 4) received the same amount of distilled water for 8 days. The fertility was assessed only in Groups 3 and 4 and after that, the animals were sacrificed and the epididymal sperm density, the serum testosterone and the testicular testosterone and 17β-estradiol were assayed. The serum, testicular and epidydimal protein contents were also determined. Results: In the acute treatment groups, the serum and testicular concentrations of testosterone remained unchanged at all the time points. Chronic treatment for 8 days induced a significant increase in the testicular weight, the serum and testicular testosterone, the testicular protein content and the sperm density (Pffect the accessory gland weights, the serum protein contents, the testicular concentration of 17β-estradiol and the fertility compared to the controls. Conclusion: Mondia whitei root extract possesses an androgenic property.

关键词： Mondia whitei testosterone sperm density fertility

Applying Earth Observation Technologies to Economic Consequence Modeling:A Case Study of COVID‑19 in Los Angeles County,California

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International Journal of Disaster Risk Science 2024年第1期15卷 18-31页

作者： fynnwin Prager Marina T.Mendoza Charles K.Huyck Adam Rose paul Amyx Gregory Yetman Kristy f.Tiampo California State University Dominguez HillsCarsonCA 90747USA ImageCat Inc.Long BeachCA 90802USA University of Southern California Los AngelesCA 90015USA CIESIN–Center for International Earth Science Information Network Columbia UniversityPalisadesNY 10964USA Cooperative Institute for Research in Environmental Sciences(CIRES) University of Colorado BoulderBoulderCO 80309USA

Earth observation(EO) technologies,such as very high-resolution optical satellite data available from Maxar,can enhance economic consequence modeling of disasters by capturing the fine-grained and real-time behavioral responses of businesses and the *** investigated this unique approach to economic consequence modeling to determine whether crowd-sourced interpretations of EO data can be used to illuminate key economic behavioral responses that could be used for computable general equilibrium modeling of supply chain repercussions and resilience *** applied our methodology to the COVID-19 pandemic experience in Los Angeles County,California as a case *** also proposed a dynamic adjustment approach to account for the changing character of EO through longer-term disasters in the economic modeling *** found that despite limitations,EO data can increase sectoral and temporal resolution,which leads to significant differences from other data sources in terms of direct and total impact *** findings from this analytical approach have important implications for economic consequence modeling of disasters,as well as providing useful information to policymakers and emergency managers,whose goal is to reduce disaster costs and to improve economic resilience.

关键词： Computable general equilibrium models COVID-19 Disaster economic impacts Earth observation Economic consequence analysis Los Angeles County

Long-term Integration Ability of the Submillimeter Wave Astronomy Satellite(SWAS)Spectral Line Receivers

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Research in Astronomy and Astrophysics 2024年第6期24卷 315-322页

作者： Bing-Ru Wang Di Li paul f.Goldsmith Jingwen Wu Chao-Wei Tsai Rudolf Schieder Gary J.Melnick National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Research Center for Astronomical Computing Zhejiang LaboratoryHangzhou 311100China Jet Propulsion Laboratory California Institute of TechnologyPasadenaCA 91109USA Institute for frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China KOSMA I.Physik.InstitutUniversität zu KölnZülpicher Str.7750937 KölnGermany Center for Astrophysics|Harvard&Smithsonian 60 Garden StreetMS 66CambridgeMA 02138USA

The Submillimeter Wave Astronomy Satellite(SWAS)was the first space telescope capable of high spectral resolution observations of terahertz spectral *** have investigated the integration ability of its two receivers and spectrometer during five and a half years of on-orbit *** CI,O_(2),H_(2)O,and^(13)CO spectra taken toward all observed Galactic sources were *** present results are based on spectra with a total integration time of up to 2.72×10~4hr(■10~8s).The noise in the spectra is generally consistent with that expected from the radiometer equation,without any sign of approaching a noise *** noise performance reflects the extremely stable performance of the passively cooled front end as well as other relevant components in the SWAS instrument throughout its mission lifetime.

关键词： telescopes space vehicles:instruments instrumentation:miscellaneous ISM:lines and bands

Tensor perturbations from bounce inflation scenario in f(Q)gravity

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 78-92页

作者： Kun Hu Tanmoy paul Taotao Qiu Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Huazhong University of Science and TechnologyWuhan 430074China National Institute of Technology Jamshedpur Department of PhysicsJamshedpur 831014India

In this paper,we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity,namely f(Q)theory,and investigate the tensor perturbations *** is well-known,the tensor perturbations generated in the very early Universe(inflation and pre-inflation regions)can account for the primordial gravitational waves(PGWs)that are to be detected by the next generation of GW *** discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation *** general form of the tensor power spectrum is obtained both for large as well as small scale *** a result,we show both kinds of modes(short or long wavelength modes),and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable—this interestingly hints an enhancement of gravitational waves’amplitude in the background of the f(Q)bounce-inflation ***,we study the LQC-like scenario as a specific case of our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.

关键词： bounce cosmology modified gravity cosmological perturbations

Exploring innovative synthetic solutions for advanced polymer-based electrochromic energy storage devices:Phenoxazine as a promising chromophore

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Journal of Energy Chemistry 2024年第4期91卷 433-452页

作者： Catalin-paul Constantin Mihaela Balan-Porcarasu Gabriela Lisa “Petru Poni”Institute of Macromolecular Chemistry Electroactive Polymers&Plasmochemistry Laboratory41A Grigore Ghica Voda AlleyIasi 700487Romania “Gh.Asachi”Technical University Iasi Faculty of Chemical EngineeringBd.Mangeron 71Iasi 700050Romania

The current investigation offers an innovative synthetic solution regarding electrochromic(EC)and energy storage applications by exploring phenoxazine(POZ)***,three POZ-based polymers(polyimide,polyazomethine,and polyamide)were synthesized to ascertain the superior *** polyamide exhibited remarkable attributes,including high redox stability during 500 repetitive CVs,optical contrast of 61.98%,rapid response times of 1.02 and 1.38 s for coloring and bleaching,EC efficiency of 280 cm^(2)C^(-1).and decays of the optical density and EC efficiency of only 12.18%and 6.23%after 1000 ***,the energy storage performance of polyamide PA was tested,for which the following parameters were obtained:74.7 f g^(-1)(CV,scan rate of 10 mV s^(-1))and 118 f g^(-1)(GCD,charging current of 0.1 A g^(-1)).Then,the polyamide was tested in EES devices,which yielded the following EC parameters:an optical contrast of 62.15%,response times of 9.24 and 5.01 s for coloring and bleaching,EC efficiency of 178 cm^(2)C^(-1),and moderate decays of 20.25%and 23.24%for the optical density and EC efficiency after 500 *** energy storage performance included a capacitance of 106 f g^(-1)(CV,scan rate of 0.1 mV s^(-1))and 9.23 f g^(-1)(GCD,charging current of 0.1 A g^(-1)),capacitance decay of 11.9%after500 cycles,and 1.7 V retention after 2 ***,two EES devices connected in series powered a 3 V LED for almost 30 s.

关键词： Polymers Phenoxazine Electrochromic Energy storage Electrochromi cenergy storage devices

Diet and monensin influence the temporal dynamics of the rumen microbiome in stocker and finishing cattle

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Journal of Animal Science and Biotechnology 2024年第2期15卷 733-748页

作者： Jianmin Chai Caleb P.Weiss paul A.Beck Wei Zhao Ying Li Jiangchao Zhao Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding College of Life Science and EngineeringFoshan UniversityFoshanChina Division of Agriculture Department of Animal ScienceUniversity of ArkansasFayettevilleARUSA Department of Animal and food Sciences Oklahoma State UniversityStillwaterOKUSA Institute of feed Research of Chinese Academy of Agricultural Sciences Key Laboratory of Feed Biotechnology of the Ministry of Agriculture and Rural AffairsBeijing 100193China

Background Stocker cattle diet and management influence beef cattle performance during the finishing stage,but knowledge of the dynamics of the rumen microbiome associated with the host are lacking.A longitudinal study was conducted to determine how the feeding strategy from the stocker to the finishing stages of production affects the temporal dynamics of rumen *** the stocker phase,either dry hay or wheat pasture were provided,and three levels of monensin were *** calves were then transported to a feedlot and received similar finishing diets with or without *** microbial samples were collected on d 0,28,85 during the stocker stage(S0,S28 and S85)and d 0,14,28,56,30 d before slaughter and the end of the trial during the finishing stage(f0,f14,f28,f56,Pre-Ba,and final).The V4 region of the bacterial 16S rRNA gene of 263 rumen samples was *** Higher alpha diversity,including the number of observed bacterial features and the Shannon index,was observed in the stocker phase compared to the finishing *** bacterial amplicon sequence variants(ASVs)differentiating different sampling time points were *** treatments during the stocker stage temporally impact the dynamics of rumen *** example,shared bacteria,including Bacteroidales(ASV19)and Streptococcus infantarius(ASV94),were significantly higher in hay rumen on S28,S85,and f0,while Bacteroidaceae(ASV11)and Limivicinus(ASV15)were more abundant in *** affected rumen microbial composition at a specific *** to feedlot significantly influenced microbiome structure and diversity in hay-fed *** taxa associated with body weight were classified,and core microbiotas interacted with each other during the *** In summary,the temporal dynamics of the rumen microbiome in cattle at the stocker and finishing stage are influenced by multiple factors of the feeding *** at the stocker phase may t

关键词： Beef cattle Diet feedlot phase Monensin Next-generation sequencing Rumen microbiota Stocker

Effects of extracts from Hibiscus macranthus and Basella alba mixture on testosterone production in vitro in adult rat testes slices

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Asian Journal of Andrology 2006年第1期8卷 111-114页

作者： paul E moundipa Silvère Ngouela Pierre Kamtchouing Etienne Tsamo félicité M.Tchouanguep Serge Carreau Laboratory of Nutrition and Biochemical Toxicology Laboratory of Organic Chemistry Department of Animal Biology and Physiology University of Yaoundé IP.O.Box 812YaoundéCameroon faculty of Science University of DschangP.O.Box 67DschangCameroon USC INRA-EA 2608.Laboratoire de Biochimie Esplanade de la paixUniversité de Caen14032 Caen-cedexFrance

Aim： To find an in vitro system for the measurement of the androgenic effects of different extracts of Hibiscus macranthus （Malvaceae） and Basella alba （Basellaceae）. Methods： The production of testosterone from testes slices incubated in two media, either Krebs-Henseleit buffer containing 0.5% Bovine serum albumin （BSA） or Dubecco＇s Modified Eagle＇s medium-f12 Ham nutrient mixture （DME/Ham f12）, under a mixture of 5% CO2 in 95% air was determined either in the presence or absence of cofactors and Hibiscus macranthus plus Basella alba （HMBA） extracts. Results： The testosterone production was increased in testes slices incubated in DME/Ham f12 medium in response to the cofactors （49%） and aqueous extracts （34%-60% according to dilutions）. Under the same atmospheric conditions, there was no positive response of the testes slices to either cofactor or HMBA extract stimulation in Krebs-Henseleit buffer containing 0.5% BSA, In further investigations related to the effect of HMBA, the DME/ Ham f12 medium was used. The results obtained from the in vitro test showed that the activity was present mainly in methylene chloride and methanol, since these extracts induced an increase in testosterone production by testes slices. Conclusion： The testes slice system is suitable to be used for further in vitro investigations of the isolation of androgenic bioactive components of plants. （Asian J Androl 2006 Jan; 8： 111-114）

关键词： testis testosterone plant extracts Hibiscus macranthus Basella alba

Tunable THz spectrum analyzer with hyperspectral resolution

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Chinese Optics Letters 2024年第7期22卷 111-116页

作者： Xin He Mingjia Yao Chengwei Qian Leixin Meng Xiaowei Liu Wenhao Tang Xiaoming Shen paul Beckett Duo Xiao Xu Liu Rui Yin School of Information and Electrical Engineering Hangzhou City UniversityHangzhou 310015China Research Center for Humanoid Sensing Zhejiang LabHangzhou 311121China State Key Laboratory of Modern Optical Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China Research Center for Intelligent Chips and Devices Zhejiang LabHangzhou 311121China STEM College RMIT UniversityMelbourneVIC 3000Australia

We present a tunable terahertz(THz)spectrum analyzer with hyperspectral resolution formed from electrically tunable metamaterial and plasmonic *** few as eight encoders based on four detectors are needed to recover 396 spectral *** incident spectra in the range of 1–5 THz can be reconstructed with a localization precision of 0.3 GHz and a minimum average mean squared error(MSE)of 6.9×10−*** proposed analyzers are faster and more portable than those based on frequency combs and power meters,and more accurate than existing fourier transform techniques,showing promising applications in pathology,biomedical imaging,and many other areas.

关键词： tunable metamaterial plasmonics spectrum analyzer.

Molecular Oxygen Abundance in Galactic Massive Star formation Regions Based on SWAS Observations

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Research in Astronomy and Astrophysics 2024年第9期24卷 85-100页

作者： Bing-Ru Wang Di Li paul f.Goldsmith Jingwen Wu Chao-Wei Tsai Donghui Quan Xia Zhang Junzhi Wang Gary J.Melnick Jin-Zeng Li Gary A.fuller Jinjin Xie National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Tsinghua University Research Center for Astronomical Computing Zhejiang Laboratory Jet Propulsion Laboratory California Institute of Technology Institute for frontiers in Astronomy and Astrophysics Beijing Normal University Xinjiang Astronomical Observatory Chinese Academy of Sciences Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi University Center for Astrophysics Harvard&Smithsonian60 Garden Street Jodrell Bank Center for Astrophysics Department of Physics&AstronomyUniversity of Manchester I.Physikalisches Institut University of Cologne

Molecular oxygen abundance is a key parameter in understanding the chemical network of the interstellar *** estimate the molecular oxygen column density and abundance for a sample of Galactic massive star formation regions based on observations from the Submillimiter Wave Astronomy Satellite （SWAS） *** obtained an averaged O2spectrum based on this sample using the （SWAS） survey data （O2,487.249 GHz,N=3–1,J=3–2）.No emission or absorption feature is seen around the supposed central velocity with a total integration time of ttotal=8.67×10～3hr and an rms noise per channel of 1.45 m *** a kinetic temperature Tkin=30 K,we derive the 3σupper limit of the O2column density to be 3.3×1015cm-2,close to the lowest values reported in Galactic massive star formation regions in previous *** corresponding O2abundance upper limit is6.7×10-8,lower than all previous results based on SWAS observations and is close to the lowest reported value in massive star formation *** a galactic scale,our statistical results confirm a generally low O2abundance for Galactic massive star formation *** abundance is also lower than results reported in extragalactic sources.

关键词： ISM: molecules galaxies: abundances ISM: lines and bands Galaxy: abundances HERSCHEL HIfI OBSERVATIONS CARBON-MONOXIDE ABUNDANCE WAVE-ASTRONOMY-SATELLITE ODIN OBSERVATIONS THERMAL BALANCE UPPER LIMITS CLOUD CORES INTERSTELLAR O-2 SEARCH