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31.
内蒙古白音诺铅锌矿床富锰单斜辉石与矿化的关系 总被引:3,自引:0,他引:3
内蒙古白音诺铅锌矿床是我国北方一个典型矽卡岩矿床,具有大而富的特点,矿区矽卡岩广泛发育,富锰单斜辉石矽卡岩与矿化的关系最为密切。单斜辉石主要为两期形成。早期富Mg,贫Fe,Mn的透辉石形成于较高的温度、fO2和PH条件下;晚期富Fe,Mn的锰钙铁辉石形成于较低的温底、fO2和PH条件下,后者与铅锌矿化具有密切的时空关第。成矿流体自矿区南西向北东方向流运过程中物理化学条件的改变,是造成矽卡岩矿物及矿 相似文献
32.
Ahmed Mostafa Soliman Neveen Samy Gadallah Michael Ohl Hathal Mohammed Al Dhafer 《Journal of Natural History》2017,51(33-34):2057-2085
The apoid wasps of the families Ampulicidae and Heterogynaidae of Saudi Arabia are revised. In Ampulicidae, four species in three genera are reported, of which three species are recorded for the first time from Saudi Arabia (Al-Baha, Asir and Riyadh regions): Ampulex assimilis Kohl, Dolichurus arabicus Ohl and Trirogma caerulea Westwood. Additionally, the family Heterogynaidae is reported for the first time from Saudi Arabia (Asir and Riyadh regions), and a new species, Heterogyna saudita sp. nov., is described, diagnosed and illustrated. An illustrated key to the species of Heterogyna from the Arabian Peninsula is provided.
www.zoobank.org/urn:lsid:zoobank.org:pub:C23C70A7-AA1C-47C0-951A-D164E7B20001 相似文献
33.
采用一种破开算子的特征线方法,将垂直平均二维水流运动方程转化为一系列一维方程式,从而由特征有限差分法求解。该模式适用于河流、河口和海湾的平面二维水流或潮流模拟。为使模式在这些水域模拟中具有边界通用性,设计了一个包含实际水域可能出现的各种不同类型边界(共28种)的边界信息库,分别给出了计算域内点和各种边界的计算公式。 相似文献
34.
Al-Mayouf SM Sunker A Abdwani R Abrawi SA Almurshedi F Alhashmi N Al Sonbul A Sewairi W Qari A Abdallah E Al-Owain M Al Motywee S Al-Rayes H Hashem M Khalak H Al-Jebali L Alkuraya FS 《Nature genetics》2011,43(12):1186-1188
Systemic lupus erythematosus (SLE) is a complex autoimmune disease that causes substantial morbidity. As is typical for many other multifactorial disorders, much of the heritability of SLE remains unknown. We identified a rare autosomal recessive form of SLE, in which autozygome analysis revealed a null mutation in the DNASE1L3 gene. The DNASE1L3-related SLE we describe was always pediatric in onset and correlated with a high frequency of lupus nephritis. Our findings confirm the critical role of impaired clearance of degraded DNA in SLE pathogenesis. 相似文献
35.
Bicknell LS Walker S Klingseisen A Stiff T Leitch A Kerzendorfer C Martin CA Yeyati P Al Sanna N Bober M Johnson D Wise C Jackson AP O'Driscoll M Jeggo PA 《Nature genetics》2011,43(4):350-355
Studies into disorders of extreme growth failure (for example, Seckel syndrome and Majewski osteodysplastic primordial dwarfism type II) have implicated fundamental cellular processes of DNA damage response signaling and centrosome function in the regulation of human growth. Here we report that mutations in ORC1, encoding a subunit of the origin recognition complex, cause microcephalic primordial dwarfism resembling Meier-Gorlin syndrome. We establish that these mutations disrupt known ORC1 functions including pre-replicative complex formation and origin activation. ORC1 deficiency perturbs S-phase entry and S-phase progression. Additionally, we show that Orc1 depletion in zebrafish is sufficient to markedly reduce body size during rapid embryonic growth. Our data suggest a model in which ORC1 mutations impair replication licensing, slowing cell cycle progression and consequently impeding growth during development, particularly at times of rapid proliferation. These findings establish a novel mechanism for the pathogenesis of microcephalic dwarfism and show a surprising but important developmental impact of impaired origin licensing. 相似文献
36.
Griffith E Walker S Martin CA Vagnarelli P Stiff T Vernay B Al Sanna N Saggar A Hamel B Earnshaw WC Jeggo PA Jackson AP O'Driscoll M 《Nature genetics》2008,40(2):232-236
Large brain size is one of the defining characteristics of modern humans. Seckel syndrome (MIM 210600), a disorder of markedly reduced brain and body size, is associated with defective ATR-dependent DNA damage signaling. Only a single hypomorphic mutation of ATR has been identified in this genetically heterogeneous condition. We now report that mutations in the gene encoding pericentrin (PCNT)--resulting in the loss of pericentrin from the centrosome, where it has key functions anchoring both structural and regulatory proteins--also cause Seckel syndrome. Furthermore, we find that cells of individuals with Seckel syndrome due to mutations in PCNT (PCNT-Seckel) have defects in ATR-dependent checkpoint signaling, providing the first evidence linking a structural centrosomal protein with DNA damage signaling. These findings also suggest that other known microcephaly genes implicated in either DNA repair responses or centrosomal function may act in common developmental pathways determining human brain and body size. 相似文献
37.
Pasternack SM von Kügelgen I Al Aboud K Lee YA Rüschendorf F Voss K Hillmer AM Molderings GJ Franz T Ramirez A Nürnberg P Nöthen MM Betz RC 《Nature genetics》2008,40(3):329-334
Hypotrichosis simplex is a group of nonsyndromic human alopecias. We mapped an autosomal recessive form of this disorder to chromosome 13q14.11-13q21.33, and identified homozygous truncating mutations in P2RY5, which encodes an orphan G protein-coupled receptor. Furthermore, we identified oleoyl-L-alpha-lysophosphatidic acid (LPA), a bioactive lipid, as a ligand for P2Y5 in reporter gene and radioligand binding experiments. Homology and studies of signaling transduction pathways suggest that P2Y5 is a member of a subgroup of LPA receptors, which also includes LPA4 and LPA5. Our study is the first to implicate a G protein-coupled receptor as essential for and specific to the maintenance of human hair growth. This finding may provide opportunities for new therapeutic approaches to the treatment of hair loss in humans. 相似文献
38.
Magdi S. El-Hawagry Mostafa R. Sharaf Hathal M. Al Dhafer Hassan H. Fadl Abdulrahman S. Aldawood 《Journal of Natural History》2016,50(19-20):1209-1236
The first list of insects (Arthropoda: Hexapoda) of Al-Baha Province, Kingdom of Saudi Arabia (KSA) was published in 2013 and contained a total of 582 species. In the present study, 142 species belonging to 51 families and representing seven orders are added to the fauna of Al-Baha Province, bringing the total number of species now recorded from the province to 724. The reported species are assigned to recognized regional zoogeographical regions. Seventeen of the species are recorded for the first time for KSA, namely: Platypleura arabica Myers [Cicadidae, Hemiptera]; Cletomorpha sp.; Gonocerus juniperi Herrich-Schäffer [Coreidae, Hemiptera]; Coranus lateritius (Stål); Rhynocoris bipustulatus (Fieber) [Reduviidae, Hemiptera]; Cantacader iranicus Lis; Dictyla poecilla Drake &; Hill [Tingidae, Hemiptera]; Mantispa scabricollis McLachlan [Mantispidae, Neuroptera]; Cerocoma schreberi Fabricius [Meloidae, Coleoptera]; Platypus parallelus (Fabricius) [Curculionidae, Coleoptera]; Zodion cinereum (Fabricius) [Conopidae, Diptera]; Ulidia ?ru?ceps Becker [Ulidiidae, Diptera]; Atherigona reversura Villeneuve [Muscidae, Diptera]; Aplomya metallica (Wiedemann); Cylindromyia sp. [Tachinidae, Diptera]; Messor semirufus (André); and Nesomyrmex denticulatus (Mayr) [Formicidae, Hymenoptera]. Also, the reduviid bug Dasycnemus sahlbergi Bergroth, that was questionably recorded from KSA is confirmed herein as occurring in KSA. The generic name Peirates (Reduviidae, Hemiptera) and the specific name of Apis florea Fabricius (Apidae, Hymenoptera) were inadvertently misspelled in the original list and are corrected here. Zoogeographically, the present study supports the original study conclusion that the insect species composition of Al-Baha Province is strongly affiliated with the Afrotropical Region rather than to the Palearctic Region or the Eremic Zone. Our insect surveys emphasize the fact that parts of the Arabian Peninsula, including Al-Baha Province, ought to be considered part of the Afrotropical Region rather than in the Palaearctic Region or the Eremic Zone. 相似文献
39.
Magdi S. El-Hawagry Mahmoud S. Abdel-Dayem Saad A. El-Sonbati Hathal M. Al dhafer 《Journal of Natural History》2017,51(25-26):1499-1530
A preliminary list of Diptera (Insecta) in Garf Raydah Nature Reserve (GRNR), Kingdom of Saudi Arabia (KSA) with remarks on their zoogeographic affinities is presented. This is the first in a series of planned faunal studies on different insect orders as an output of a project proposed to study the entire entomofauna of GRNR. A total number of 177 Diptera species belonging to 130 genera, representing 38 families has been listed. Some species have been identified only to genus and listed herein as genera that were not previously recorded from KSA or of a taxonomic or faunal importance. The list records five families, 11 genera and 31 species for the first time in KSA, namely: the families Acroceridae, Asteiidae, Chamaemyiidae, Heleomyzidae and Pipunculidae; the genera Acrocera (Acroceridae), Eremisca (Asilidae), Asteia (Asteiidae), Chamaemyia sp. (Chamaemyiidae), Ochthera (Ephydridae), Physoconops (Conopidae), Pseudoleria (Heleo-myzidae), Salentia (Therevidae), Sapromyza (Lauxaniidae), Sternobrithes (Stratiomyidae), Tomosvaryella (Pipunculidae); and the species Apoclea algira (Linnaeus), Apoclea femoralis (Wiedemann), Promachus rectangularis Loew, Eremisca sp. and Oligopogon nitidus Efflatoun [Asilidae]; Phycus sp., Salentia sp. and Thereva nobilitata (Fabricius) [Therevidae]; Drapetis flavipes Macquartand Platypalpus flavicornis (Meigen) [Hybotidae]; Acrocera sp.1 and Acrocera sp.2 [Acroceridae]; Aspida-cantha atra Kertesz and Sternobrithes sp. [Stratiomyidae]; Tomos-varyella sp.1 and Tomosvaryella sp.2 [Pipunculidae]; Eristalinus taeniops (Wiedemann) and Eumerus amoenus Loew [Syrphidae]; Asteia sp. [Asteiidae]; Chamaemyia sp. [Chamaemyiidae]; Physoconops sp., and Thecophora fulvipes Rubineau-Desvoidy [Conopidae]; Ochthera sp. [Ephydridae]; Pseudoleria pectinata (Loew) [Heleomyzidae]; Cestrotus megacephalus Loew and Sapromyza sp. [Lauxaniidae]; Campylocera oculata Hendel [Pyrgotidae]; Australosepsis niveipennis (Becker) [Sepsidae]; Metasphenisca transilis Munro [Tephritidae]; Anthomyia xanthopus (Hennig) [Anthomyiidae]; and Sarcophaga inaequalis Austen [Sarcophagidae]. More than 50% of the recorded fly species are of an Afrotropical affinity, whereas the Palaearctic elements did not exceed 20%. Only 7% of the species were of both Afrotropical and Palaearctic affinities, and Oriental elements were close to nil. This emphasizes the fact that the southwestern part of KSA, including the study area, belonging to Asir Province, ought to be part of the Afrotropical Region rather than the the Palaearctic Region. 相似文献
40.
Neveen S. Gadallah Ahmed M. Soliman Usama M. Abu El-Ghiet Tarek Y. Elsheikh Hathal M. Al Dhafer 《Journal of Natural History》2018,52(31-32):2071-2096
The family Leucospidae (Hymenoptera: Chalcidoidea) from Saudi Arabia is reviewed. Specimens were mainly collected from the south-western region of the country – Raydah (Abha, Asir), Sajid (Farasan Islands, Jazan) and Wadi Tourabah (Mandaq, Al Baha); and from Egypt – Wadi Khoshb (Sinai Peninsula), as well as a specimen (Leucospis elegans Klug) deposited in the Efflatoun Bey collection, Cairo University, Egypt. The genus Micrapion Kriechbaumer is here recorded for the first time from the fauna of the Arabian Peninsula, with a single species, M. clavaforme. Leucospis arabica Gadallah and Soliman sp. nov. (dorsigera group) is described. Leucospis africana (elegans group) is also newly recorded from the Saudi Arabian fauna, in addition to L. elegans which has been previously recorded. An illustrated key and a list of all leucospid species recorded and expected to occur in Saudi Arabia are provided.
www.zoobank.org/lsid:Zoobank.org:pub:40BEF37F-0D92-4AEF-9990-30C1CFC3A7A7 相似文献