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Speciation with gene flow via cycles of isolation and migration:insights from multiple mangrove taxa

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National Science Review 2019年第2期6卷 275-288页

作者： Ziwen He Xinnian Li Ming Yang Xinfeng Wang cairong Zhong Norman c.Duke chung-I Wu Suhua Shi State Key Laboratory of Biocontrol Guangdong Key Lab of Plant Resources Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education InstitutesSchool of Life Sciences Sun Yat-Sen University Department of Ecology and Evolution University of Chicago cAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of Sciences Hainan Dongzhai Harbor National Nature Reserve Administration centre for Tropical Water and Aquatic Ecosystem Research James Cook University

Allopatric speciation requiring an unbroken period of geographical isolation has been the standard model of neo-Darwinism. While doubts have been repeatedly raised, strict allopatry without any gene flow remains a plausible mechanism in most cases. To rigorously reject strict allopatry, genomic sequences superimposed on the geological records of a well-delineated geographical barrier are necessary. The Strait of Malacca,narrowly connecting the Pacific and Indian Ocean coasts, serves at different times either as a geographical barrier or a conduit of gene flow for coastal/marine species. We surveyed 1700 plants from 29 populations of 5 common mangrove species by large-scale DNA sequencing and added several whole-genome assemblies. Speciation between the two oceans is driven by cycles of isolation and gene flow due to the fluctuations in sea level leading to the opening/closing of the Strait to ocean currents. Because the time required for speciation in mangroves is longer than the isolation phases, speciation in these mangroves has proceeded through many cycles of mixing-isolation-mixing, or MIM, cycles. The MIM mechanism, by relaxing the condition of no gene flow, can promote speciation in many more geographical features than strict allopatry can. Finally, the MIM mechanism of speciation is also efficient, potentially yielding mn(m > 1) species after n cycles.

关键词： speciation gene flow allopatry geographical isolation mangrove

Haploids in the genetic improvement of solanaceous species

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Agricultural Science & Technology 2004年第2期5卷 2-7页

作者： George c.c. Tai Potato Research centre Agriculture &Agri Food canada Fredericton N.B. E3B 4Z7

Research work in haploids represents a very fruitful field in the Solanaceae crop species. The various applications of haploids in genetic and breeding research in potatoes, tobacco, tomato and pepper are reviewed.

关键词： haploid solanaceae potatoes tobacco tomato pepper genetic improvement

fd-DOMAINS AND rf-DISJUNcTIVE LANGUAGes

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chinese Science Bulletin 1989年第5期34卷 356-360页

作者：郭聿琦 c.M.REIS G.THIERRIN Lanzhou University University of Western Ontario

Ⅰ. INTROOUcTIONLet X be a nonempty finite set called an alphabet, and X~* the free monoid generated by X and X^+=X~*—{1}, where 1 is the identity of X~* called the empty word over X. Elements and subsets of X~* are ... 详细信息

Ⅰ. INTROOUcTIONLet X be a nonempty finite set called an alphabet, and X~* the free monoid generated by X and X^+=X~*—es, where 1 is the identity of X~* called the empty word over X. Elements and subsets of X~* are called words and languages over X respectively. The length of a word x which is the number of the letters occurring in x will be denoted by lg(x).

关键词： fd-domain rf-disjunctive language uniformly dense language.

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Epidemiological study of hypertensive retinopathy in the primary care setting: Retrospective cross-sectional review of retinal photographs

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Family Medicine and community Health 2016年第4期4卷 13-21页

作者： Lap-kin chiang Michael K.c.Yau cheuk-wai Kam Lorna V.Ng Benny c.Y.Zee Family Medicine and General Outpatient Department Kwong Wah HospitalHospital AuthorityHong KongChina The Jockey club School of Public Health and Primary care The Chinese University of Hong KongHong KongChina

Objective:The objective is to estimate the prevalence and grading of hypertensive retinopa-thy in the primary care setting;examine the patient characteristics associated with hypertensive retinopathy;and examine the association of hypertensive retinopathy and other hypertension ***:This is a retrospective cross-sectional *** included adult hypertensive patients with available and gradable retinal ***:Two hundred fifty-six male hypertensive patients(34.3%)and 491 female hyper-tensive patients(65.7%)were *** average duration of hypertension was 7.2 years,and 49.8%and 41.2%of patients were taking one or two antihypertensive medications *** 1491 qualified retinal photographs(744 right eye and 747 left eye),24.9%,62.6%,and 12.5%were classified as showing normal,mild,and moderate hypertensive retinopathy *** three commonest retinal signs were generalized or focal arteriolar narrowing(650 cases,43.6%),hard exudates(168 cases,11.3%),and opacity(copper or silver wiring)of the arteriolar wall(166 cases,11.1%).Patients older than 61 years,having hypertension for more than 15 years,or taking three or more antihypertensive medications were significantly associated with hyperten-sive retinopathy(Pconclusion:In a primary care clinic in Hong Kong,77.1%of hypertensive patients had hypertensive *** hypertensive retinopathy was the commonest target organ damage for hypertensive patients in a primary care clinic.

关键词： Hypertensive retinopathy retinal photograph primary care

Antioxidant,cytotoxic,and anti-venom activity of Alstonia parvifolia ***

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Asian Pacific Journal of Tropical Biomedicine 2021年第10期11卷 460-468页

作者： Maria carmen S.Tan Mary Stephanie S.carranza Virgilio c.Linis Raymond S.Malabed Yves Ira A.Reyes Francisco c.Franco,Jr. Glenn G.Oyong chemistry Department De La Salle University2401 Taft AvenueManila 1004Philippines Biology Department De La Salle University2401 Taft AvenueManila 1004Philippines Department of chemistry Graduate School of ScienceOsaka UniversityOsaka 563-0034Japan Molecular Science Unit Laboratory Center for Natural Sciences and Environmental ResearchDe la Salle University2401 Taft AvenueManila 1004Philippines

Objective:To evaluate antioxidant,cytotoxic,and anti-venom capacity of crude bark extracts of Alstonia parvifolia ***:Gas chromatography-mass spectrometry(Gc-MS)and energy dispersive X-ray analyses were accomplished to characterize the chemical constituents of Alstonia *** characterization was evaluated using an inhibitory phospholipase A_(2)(PLA_(2))assay,DPPH,and cytotoxicity *** the constituents listed in the Gc-MS analyses,molecular docking was conducted to inspect the binding energies between the chosen compounds and selected PLA_(2) ***:Gc-MS analyses showed that the Alstonia parvifolia crude extract consisted predominantly of acetylmarinobufogenin(14.89%),γ-sitosterol(10.44%),3-O-methyl-D-glucose(5.88%),3,5-dimethoxy-4-hydroxyphenylacetic acid(5.30%),(2α,5α)-17-methoxyaspidofractinin-3-one(AFM)(4.08%),and 2,3,5,6,7,8,9-heptahydro-1-phenyl-5-(p-chlorophenylimino)-1H-benzo[e][1,4]thiazepine(HPT)(1.37%).The principal elemental components of Alstonia parvifolia were ca(4.012%)and K(1.496%),as exhibited by energy dispersive X-ray *** parvifolia showed significant free radical scavenging ability(Ic_(50):0.287 mg/mL)and was non-cytotoxic to normal HDFn cells(Ic_(50)>100μg/mL).Moreover,Alstonia parvifolia was favorably cytotoxic to McF-7(Ic_(50):4.42µg/mL),followed by H69PR,HT-29,and THP-1,with Ic_(50) values of 4.94,5.07,and 6.27µg/mL,*** parvifolia also displayed notable inhibition against PLA_(2) activity of Naja philippinensis Taylor venom with Ic_(50) of(15.2±1.8)μg/*** and cluster analyses projected negative binding energies from AFM(−6.36 to−9.68 kcal/mol),HPT(−7.38 to−9.77 kcal/mol),and acetylmarinobufogenin(−7.22 to−9.59 kcal/mol).These calculations were for the particular interactions of Alstonia parvifolia constituents to PLA_(2) homologues where the utmost affinity was detected in HPT owing to the dipole interactions with amino acid ***:The bark e

关键词： Alstonia parvifolia Merr. Naja philippinensis Taylor Gas chromatography-electron ionization-mass spectrometry Secretory phospholipase A_(2) cytotoxicity assay Anti-venom

Fossil Vertebrates from Kuangyuan, N. Szechuan, china

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地质学报 1942年第Z2期 304-322页

作者： c. c. YOUNG Laboratory of Vertebrate Palacontology Geological Survey of china

During the late spring of 1941, Messrs. M. N. Bien, T. H. Mi and the present writer were fortunate enough to discover several localities of vertebrate fossils. The geological condition will be reported in another pape... 详细信息

关键词： china Fossil Vertebrates from Kuangyuan Szechuan

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

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Journal of Semiconductors 2006年第4期27卷 635-640页

作者： Pinsukanjana P Vargason K Herrera M Ontiveros D Boehme c Intelligent Epitaxy Technology Inc.RichardsonTX 75081USA

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4×100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux *** state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb.A Sb composition variation of less than ±0.1 atomic percent across a 4×100mm platen configuration has been *** large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent Dc characteristics,such as BV_cEO>6V and a Dc current gain of 45 at 1kA/cm2 for an emitter size of 50μm×50μ*** devices have a 40nm thick GaAsSb base with p-doping of 4.5×*** with an emitter size of 4μm×30μm have a current gain variation less than 2% across the fully processed 100mm wafer.f_t and f_max are over 50GHz,with a power efficiency of 50%,which are comparable to standard power GaAs HBT *** results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.

关键词： InP GaAsSb 多晶片产品传感器

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colliculitis as a causative Factor in Seminal Emission

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中华医学杂志 1917年第2期3卷 19-25页

作者： Liau c. c.

(五)肾脏之关系肾脏有病而现糖尿者。颇不多见。惟慢性肾炎。間或有之。然遇真正糖尿症。试一验其肾脏。卒無可据之病理变化。但马林氏Mering之实验。医者要不可不注意及之。氏嘗从苹果树皮中。采其精液。制成一种糖质。名之曰佛罗力新...

(五)肾脏之关系肾脏有病而现糖尿者。颇不多见。惟慢性肾炎。間或有之。然遇真正糖尿症。试一验其肾脏。卒無可据之病理变化。但马林氏Mering之实验。医者要不可不注意及之。氏嘗从苹果树皮中。采其精液。制成一种糖质。名之曰佛罗力新。Phlorizin使人或犬服之。或注射於其皮内。则现有糖尿症。惟血中糖质。不见增加。由此以观。其糖或直接由肾脏造

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Buruli ulcer in Nigeria:results of a pilot case study in three rural districts

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Infectious Diseases of Poverty 2016年第1期5卷 328-336页

作者： Kingsley N.Ukwaja Anthony O.Meka Alphonsus chukwuka Kingsley B.Asiedu Kristina L.Huber Miriam Eddyani Joseph N.chukwu Moses c.Anyim c.ar.es c.Nwafor Daniel c.Oshi Nelson O.Madichie Ngozi Ekeke Martin Njoku Kentigern Ntana Department of Medicine Federal Teaching HospitalFMC RdAbakalikiEbonyi StateNigeria Medical Department German Leprosy and TB Relief AssociationEnuguEnugu StateNigeria St Benedict’s Tuberculosis and Leprosy Rehabilitation Hospital OgojaCross River StateNigeria Global Buruli Ulcer Initiative Department of Control of Neglected Tropical DiseasesWorld Health OrganizationGenevaSwitzerland Department of Infectious Diseases and Tropical Medicine University HospitalLudwig-Maximilians UniversityMunichGermany Mycobacteriology Unit Department of MicrobiologyInstitute of Tropical MedicineAntwerpBelgium

Background:Buruli ulcer(BU),also known as Mycobacterium ulcerans disease,is the third most common mycobacterial disease *** BU disease has been diagnosed among Nigerians in neighbouring West African countries,data on the burden of the disease in Nigeria itself are *** study aimed to assess the magnitude and epidemiology of BU in the South South region of ***:We conducted a cross-sectional survey in the Ogoja territory(comprising 31 communities).We undertook sensitisation programmes centred on BU in 10 of the *** were asked to identify community members with long-standing ulcers,who were then invited for *** also contacted traditional healers to refer their clients who had non-healing *** suspected cases had a full clinical evaluation and laboratory *** cases were given treatment in a referral hospital in the ***:We diagnosed 41 clinical BU cases;36(87.8%)of which were confirmed by quantitative polymerase chain reaction(qPcR).These 36 PcR-confirmed cases were diagnosed in a total population of 192,169 ***,the estimated crude prevalence of BU was 18.7 per 100,000 population,varying from 6.0 to 41.4 per 100,000 in the districts *** majority(66.7%)of the cases were *** 92%of the BU lesions were located on the patients’*** differences were observed between the sexes in terms of the location of the *** age of the patients ranged from four to 60 years,with a median age of 17 *** 35(100%)patients who consented to treatment completed chemotherapy as *** the treated cases,29(82.9%)needed and received *** cases healed,but 29(82.9%)had some limitations in *** with limitations in movement occurred in 18/19(94.7%)and 8/10(80.0%)of patients with lesions>15 cm(category III)and 6–15 cm in diameter(category II),*** median duration of treatment was 130(87–164)days for children and

关键词： Buruli ulcer Mycobacterium ulcerans Epidemiology case finding Endemicity Ogoja cross River State Nigeria