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overview of priorities,threats,and challenges to biodiversity conservation in the southern Philippines

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Regional Sustainability 2023年第2期4卷 203-213页

作者： Angelo Rellama AGDUMA Francisco Gil GARcIA Ma.Teodora cABASAN Jonald PIMENTEL Renee Jane ELE Meriam RUBIo Sedra MURRAY Bona Abigail HILARIo-HUSAIN Kier celestial Dela cRUZ Sumaira ABDULLAH Shiela Mae BALASE Krizler cejuela TANALGo Ecology and conservation Research Laboratory Department of Biological SciencesCollege of Science and MathematicsUniversity of Southern MindanaoCotabatoKabacan9407the Philippines Mindanao open Biodiversity Information Project(MoBIoS+) c/o Ecology and Conservation Research LaboratoryDepartment of Biological SciencesCollege of Science and MathematicsUniversity of Southern MindanaoCotabatoKabacan9407the Philippines Department of Biological Sciences College of Science and MathematicsUniversity of Southern MindanaoCotabatoKabacan9407the Philippines State Key Laboratory for conservation and Utilization of Subtropical Agrobioresources Guangxi UniversityNanning530004China Guangxi Key Laboratory of Forest Ecology and conservation College of ForestryGuangxi UniversityNanning530004China Department of Agricultural Economics College of BusinessDevelopment Economics and ManagementUniversity of Southern MindanaoCotabatoKabacan 9407the Philippines Department of Mathematics and Statistics College of Science and MathematicsUniversity of Southern MindanaoCotabatoKabacan9407the Philippines Practical Genomics La boratory Department of BiologyCollege of ScienceDe La Salle University-ManilaManila1004the Philippines

Human activities have severely impacted on many species and ***,understanding the local biodiversity situation is crucial for implementing effective biodiversity conservation *** in the southern Philippines is home to various unique species,particularly in its pristine ***,the available biodiversity data for many terrestrial vertebrates and key areas remain *** address this issue,we synthesized published literature related to biodiversity from 2000 to 2022 in ***,this analysis used four key terrestrial vertebrates(amphibians,reptiles,birds,and mammals)in Mindanao as research *** to our findings,there was a significant and positive correlation between the number of biodiversity studies and species *** terms of species richness,birds were the most recorded group(n=334 spp.),followed by reptiles(n=108 spp.),mammals(n=70 spp.),and amphibians(n=52 spp.).We also found that the number of endemic and threatened species varies geographically and across taxonomic ***,we discovered a significant disparity in the information available on biodiversity in different provinces of *** example,the western provinces of Mindanao have had no record of biodiversity for more than two ***,we found that the changes in tree cover loss were consistent with biodiversity records,but this correlation is only significant for ***,we highlighted some critical threats and challenges to biodiversity,including deforestation,agricultural expansion,mining,and their impact on biodiversity conservation in *** findings suggested that biodiversity conservation should focus not only on areas with high levels of biodiversity but also on areas lacking biodiversity *** do this,we call for strengthening collaboration among various institutions and digitizing and centralizing of information related to *** gaining a deeper understanding of biodiversit

关键词： Biodiversity conservation Tree cover loss Mindanao Terrestrial vertebrates Endemic and threatened species

Geochemical characteristics of abiogenic alkane gases

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Petroleum Science 2009年第4期6卷 327-338页

作者： Yunyan ni Jinxing Dai Petrochina Res Inst Petr Explorat & Dev Beijing 100083 Peoples R China

Recently abiogenic alkanes have been found in various locations in the world and other celestial bodies. The chemical composition of abiogenic alkane gases varies widely. The content of methane is low and nearly no c2+ is found in the abiogenic alkane gases from fluid inclusions in volcanic rocks or hot springs in china. In the unsedimented submarine hydrothermal vent system c1/c2+ ratios are much greater than those for the thermogenic gases, mostly >800 and in some cases up to 8,000. In the Songliao Basin, china, c1/c2+ of some abiogenic gases are often less than 150. Abiogenic alkane gases which have been found in nature often have carbon isotopic reversal among c1–c4 alkanes (δ13c1>δ13c2>δ13c3>δ13c4), whereas both regular and reversed hydrogen isotope distribution pattern among c1–c4 alkanes have been reported. The δ13c of abiogenic methane is mainly greater than ?30‰ though laboratory synthesized methane can have δ13c as low as ?57‰, and its δD1 values vary widely and overlap with biogenic gases. High 3He/4He ratios often indicate the addition of mantle-derived helium and are related to abiogenic gases. However, some biogenic gases can also have high 3He/4He ratios up to 8. The cH4/3He end-member is often lower than 106 for abiogenic alkane gases while greater than 1013 for biogenic gases, and the values between these two end-members often reflect the mixing of biogenic and abiogenic gases.

关键词： Abiogenic origin alkane gas carbon isotopic reversal trend geochemical characteristics

The first photometric investigation of the contact binary oQ cam

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Research in Astronomy and Astrophysics 2020年第11期20卷 252-258页

作者：郭雅妮李凯夏琪琪高兴江林巧刘媛 Shandong Key Laboratory of optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai 264209China Xinjiang Astronomical observatory Urumqi 830011China Artificial Intelligence Key Laboratory of Sichuan Province Sichuan University of Science&EngineeringZigong 643000China Qilu Institute of Technology Jinan 250200China

The first charge-coupled device photometric light curves in B,V,Rc,and Ic bands of the short-period contact binary star oQ cam are *** analyzing the light curves with the WilsonDevinney code,it is found that oQ cam is a W-type shallow contact binary star with a contact degree of f=20.2%.Based on the o-c analyzing,the orbit period displays a long term increasing with a rate of d P/dt=4.40×10^-7 d *** increasing in orbit period can be interpreted by mass transfer from the less massive component to the more massive *** the orbit period increases,oQ cam would evolve from the present shallow contact configuration to a non-contact *** it may be a potential candidate to confirm the thermal relaxation oscillation theory.

关键词： stars binaries close stars binaries eclipsing stars evolution stars individual(oQ cam)

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金鱼望天眼性状受环境和遗传影响的初步研究

淡水渔业 2022年第1期52卷 66-73页

作者：李荣妮孙砚胜田仲王赛赛张欣北京市水产科学研究所暨国家淡水渔业工程技术研究中心北京100068 农业农村部都市农业(北方)重点实验室北京100097 渔业生物技术北京市重点实验室北京100097

试验旨在探索研究不同的水深和容器的透光性是否影响望天眼金鱼最终成功翻眼率,并通过杂交试验,探讨金鱼望天眼性状是否稳定遗传。试验首先选取红望天眼金鱼两雌一雄和一雄偏龙睛五花金鱼,进行人工混合繁殖,随机选取后代分四组,分别在... 详细信息

试验旨在探索研究不同的水深和容器的透光性是否影响望天眼金鱼最终成功翻眼率,并通过杂交试验,探讨金鱼望天眼性状是否稳定遗传。试验首先选取红望天眼金鱼两雌一雄和一雄偏龙睛五花金鱼,进行人工混合繁殖,随机选取后代分四组,分别在透明玻璃缸水深15 cm(A)、透明玻璃缸水深30 cm(B)、不透光塑缸水深15 cm(c)和不透光塑缸水深30 cm(D)环境中养殖290 d,统计最终金鱼成功翻眼率,进行双因素方差分析,同时进行望天眼金鱼与翻眼不成功的介于望天和龙睛中间体的金鱼进行正反交和各自自交,统计后代最终的眼睛性状。结果显示:水深对望天眼金鱼成功翻眼率影响极显著,容器透光性对其影响不显著;亲本翻眼程度越大,其后代望天比例越高,表明望天眼性状受遗传影响较大,并且一定程度上受母体遗传效应影响。

关键词：望天眼金鱼望天率水深透光性遗传母体效应

The technology for detection of gamma-ray burst with GEcAM satellite

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Radiation Detection Technology and Methods 2022年第1期6卷 12-25页

作者： X.Q.Li X.Y.Wen Z.H.An c.cai Z.chang G.chen c.chen Y.Y.Du M.Gao R.Gao K.Gong D.Y.Guo J.J.He D.J.Hou Y.G.Li c.Y.Li G.Li L.Li X.F.Li M.S.Li X.H.Liang X.J.Liu Y.Q.Liu F.J.Lu H.Lu B.Meng W.X.Peng F.Shi X.L.Sun H.Wang J.Z.Wang Y.S.Wang H.Z.Wang X.Wen S.Xiao S.L.Xiong Y.B.Xu Y.P.Xu S.Yang J.W.Yang Q.B.Yi D.L.Zhang Fan Zhang S.N.Zhang c.Y.Zhang c.M.Zhang Fei Zhang X.Y.Zhao Y.Zhao X.Zhou c.S.Zhang J.P.Yu L.chang K.K.Zhang J.Huang Y.M.chen X.B.Han Institute of High Energy Physics CASBeijing 100049China Xiangtan University Xiangtan 411105China Beijing Normal University Beijing 110875China Beijing Glass Research Institute Beijing 101100China Innovation Academy for Microsatellites of cAS Shanghai 201204China

Introduction The main physical objective of the GEcAM satellite is to detect gamma-ray bursts,which is related to gravitational waves of double compact object *** GEcAM satellite also detects and investigates various bursts of high-energy celestial *** and methods In this study,we designed,developed and calibrated the payload and launched it into orbit with GEcAM *** payload consists of the gamma ray detector(GRD,for detecting 4 keV–4 MeV X/γray),the charged particle detector(cPD,for detecting 150 keV–5 MeV charged particle),and the electronic box(EBoX).The all-sky field coverage is achieved via two 229-degree large-area satellites positioned 180 degrees apart and are on opposite sides of the *** satellite is equipped with 25 GRDs and 8 cPDs;thus,the satellite can identify charged particle bursts in ***-ray detectors adopt lanthanum bromide crystal technology combined with silicon *** is the first time that this technology was used massively in space *** The GEcAM satellite can quickly determine the direction of gamma-ray bursts(positioning)via indexing and fitting method,while the transmit variability,energy spectrum and direction of the gamma-ray bursts guide subsequent observations through the Beidou-3 RDSS in quasi-real *** will play an important role in the study of high energy celestial bursts.

关键词： GEcAM Gamma-ray burst Lanthanum bromide crystal Silicon photomultiplier Beidou short message

The Necessity of a High-grade Telescope for Education and Future Research Activities in the Philippines

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天文研究与技术 1999年第S1期 103-108页

作者： c. P. celebre, M. Sc (Astronomy Research and Development Section (AsRDS), AGSSB, PAGASA, philippines)

Astronomy has been practiced in the Philippines for the past century. However, the study of celestial objects in the country is confined to its observation and publication of data. There is no course in astrnonmy in the tertiary level while it is briefly covered in the general science curriculum of the elementary and high schools in the country. No serious research activity has been conducted primarily due to lack of necessary research instruments such as a high grade telescope and the required formal education or training of staff in astronomy to perform such an activity. The possible donation of a 45cm high grade telescope with its accessories by the government of Japan, through its cultural Grant aid Program, to the Philippines will upgrade the capability of the Astronomical observatory of the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) to observe and study astronomical objects and phenomena. Likewise, it will improve services in the promotion of the science of astronomy in the country, especially in education and training of science teachers.

关键词： The Necessity of a High-grade Telescope for Education and Future Research Activities in the Philippines

FAST discovery of an extremely radio-faint millisecond pulsar from the Fermi-LAT unassociated source 3FGL J0318.1+0252

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Science china(Physics,Mechanics & Astronomy) 2021年第12期64卷 10-17页

作者： Pei Wang Di Li colin J.clark Pablo M.Saz Parkinson Xian Hou Weiwei Zhu Lei Qian Youling Yue Zhichen Pan Zhijie Liu Xuhong Yu Shanping You Xiaoyao Xie Qijun Zhi Hui Zhang Jumei Yao Jun Yan chengmin Zhang Kwok Lung Fan Paul S.Ray Matthew Kerr David A.Smith Peter F.Michelson Elizabeth c.Ferrara David J.Thompson Zhiqiang Shen Na Wang FAST&Fermi-LAT collaboration cAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of chinese Academy of Sciences Beijing 100049China Jodrell Bank centre for Astrophysics Department of Physics and AstronomyUniversity of ManchesterManchester M139PLUK Department of Physics and Laboratory for Space Research University of Hong KongHong Kong 999077China Santa cruz Institute for Particle Physics University of CaliforniaSanta Cruz CA 95064USA Yunnan observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of celestial objects Chinese Academy of SciencesKunming 650216China School of computer Science and Technology Key Laboratory of Information and Computing Guizhou ProvinceGuizhou Normal UniversityGuiyang 550001China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Physics Department Stanford UniversityStanford CA 94305USA UMcP/cRESST/GSFc NASAGreenbeltMaryland MD 20771USA GSFc NASAGreenbeltMaryland MD 20771USA centre d’´Etudes Nucl´eaires de Bordeaux Gradignan IN2P3/CNRSUniversit´e BordeauxGradignan 33175France Space Science Division U.S.Naval Research LaboratoryWashington DC 20375-5352USA Shanghai Astronomical observatory Chinese Academy of SciencesShanghai 200030China Xinjiang Astronomical observatory Urumqi 830011China Department of Physics University of MarylandCollege Park MD 20742USA NAoc-UKZN computational Astrophysics centre University of KwaZulu-NatalDurban 4000South Africa 不详

High sensitivity radio searches of unassociated γ-ray sources have proven to be an effective way of finding new pulsars. Using the Five-hundred-meter Aperture Spherical radio Telescope(FAST) during its commissioning phase, we have carried out a number of targeted deep searches of Fermi Large Area Telescope(LAT) γ-ray sources. on February 27, 2018 we discovered an isolated millisecond pulsar(MSP), PSR J0318+0253, coincident with the unassociated γ-ray source 3 FGL J0318.1+0252. PSR J0318+0253 has a spin period of 5.19 ms, a dispersion measure(DM) of 26 pc cm-3 corresponding to a DM distance of about 1.3 kpc, and a period-averaged flux density of(~11±2) μJy at L-band(1.05-1.45 GHz). Among all high energy MSPs, PSR J0318+0253 is the faintest ever detected in radio bands, by a factor of at least ~4 in terms of L-band fluxes. With the aid of the radio ephemeris, an analysis of 9.6 years of Fermi-LAT data revealed that PSR J0318+0253 also displays strong γ-ray pulsations. Follow-up observations carried out by both Arecibo and FAST suggest a likely spectral turn-over around 350 MHz. This is the first result from the collaboration between FAST and the Fermi-LAT teams as well as the first confirmed new MSP discovery by FAST, raising hopes for the detection of many more MSPs. Such discoveries will make a significant contribution to our understanding of the neutron star zoo while potentially contributing to the future detection of gravitational waves, via pulsar timing array(PTA) experiments.

关键词： FAST pulsar radio gamma rays