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Dark Matter Creation and Anti-Gravity Acceleration of the Expanding Universe 认领
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作者 F. C. Hoh 《现代物理(英文)》 2021年第3期139-160,共22页
Dark matter is identified as negative relative energy between quarks in proton and is generated in cold hydrogen gas with pressure gradient in gravitational field. Positive relative energy PRE can be generated between... Dark matter is identified as negative relative energy between quarks in proton and is generated in cold hydrogen gas with pressure gradient in gravitational field. Positive relative energy PRE can be generated between quarks in protons in cold hydrogen gas in outskirts of the universe. The mechanisms for such creation of dark matter and PRE are reviewed and updated in greater detail and clearer manner. The so-generated dark matter in a galaxy can account for the galaxy’s rotation curve. Star formation in this galaxy uses up the hydrogen atoms and thereby reduces its dark matter content. Dark matter created in intergalactic hydrogen gas can form filaments. In a hypothetical model of the universe, a hydrogen atom with a small amount of negative relative energy or dark matter at the outskirts of this universe can via collisions with other atoms turn into one with a small positive relative energy PRE. Once such a sign change takes place, gravitational attraction switches to anti-gravity repulsion unopposed by any pressure gradient. This leads to a “run away” hydrogen atom moving away from the mass center of the universe and provides a basic mechanism for the accelerating expansion of the universe. This theoretical expansion and the measured redshift data are both compatible with the conception of an acceleratingly expanding universe and complement each other. But they cannot verify each other directly because the present model has been constructed for purposes different from those of the measurements. But it can be shown that both approaches do support each other qualitatively under certain circumstances for small velocities. Dark matter and PRE in the present model are not foreign objects like WIMPs and dark energy-cosmological constant but can only be created in cold hydrogen gas in gravitational field. To achieve this, infrequent collisions among the hydrogen atoms must take place. Dark matter was created first and can eventually later evolve into PRE in the outskirts of the universe and in the intergalactic 展开更多
关键词 Relative Energy between Quarks Scalar Strong Interaction Hadron Theory SSI Negative Relative Energy Dark Matter Positive Relative Energy PRE Anti-Gravity Repulsion Universe Expansion Proton Orbit Hubble’s Law
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Pre S1、HBV-DNA及乙肝五项指标对乙型肝炎肝脏纤维化诊断的临床价值 认领 被引量:1
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作者 罗艳 《标记免疫分析与临床》 CAS 2020年第1期53-57,62共6页
目的分析血清前S1抗原(Pre S1)、乙肝病毒DNA(HBV-DNA)及乙肝五项指标对乙型肝炎肝脏纤维化诊断的临床价值。方法选取2017年1月至2019年2月我院收治的乙型肝炎患者276例,其中慢性乙型肝炎228例(轻度、中度、重度分别89、80、59例)、肝硬... 目的分析血清前S1抗原(Pre S1)、乙肝病毒DNA(HBV-DNA)及乙肝五项指标对乙型肝炎肝脏纤维化诊断的临床价值。方法选取2017年1月至2019年2月我院收治的乙型肝炎患者276例,其中慢性乙型肝炎228例(轻度、中度、重度分别89、80、59例)、肝硬化48例,分析其血清Pre S1、HBV-DNA载量、乙肝五项指标、肝纤维化指标[血清Ⅲ型前胶原(PCⅢ)、Ⅳ型胶原(CⅣ型)、层连蛋白(LN)、透明质酸(HA)]水平,对比不同乙型肝炎患者的HBV-DNA载量、乙肝五项者指标的差异,采用Spearman法分析相关性。结果肝硬化患者血清Pre S1阳性率、HBV-DNA载量均高于慢性乙型肝炎(P<0.05);肝硬化组血清PCⅢ、CⅣ、LN、HA水平较慢性乙型肝炎者高,且在慢性乙型肝炎中随病情加重,患者PCⅢ、CⅣ、LN、HA水平上升(P<0.05);随HBV DNA载量增加,乙型肝炎患者血清Pre S1阳性率及血清PCⅢ、CⅣ、LN、HA水平增加(P<0.05);大三阳组Pre S1阳性率、HBV-DNA载量均高于其他各组(P<0.05),小三阳组Pre S1阳性率、HBV-DNA载量也高于除大三阳组外的其他各组(P<0.05);Spearman相关分析显示,乙型肝炎患者血清Pre S1阳性率、HBV-DNA载量与乙肝大三阳、小三阳及血清PCⅢ、LN均存呈正相关,Pre S1阳性率与HBV-DNA载量也呈正相关(P<0.05)。结论Pre S1、HBV-DNA及乙肝五项指标均可较好判断乙型肝炎患者肝脏纤维化程度,值得在基层医院推广。 展开更多
关键词 PRE S1 HBV-DNA 乙肝五项 乙型肝炎 肝脏纤维化
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为什么美国人的午餐更贵 认领
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作者 赵斌 《疯狂英语:冲刺版》 2020年第11期33-34,62,共3页
今年夏天,为欧美的白领上班族供应三明治的Pret A Manger在菜单中加上了龙虾卷。其在英国的售价是5.99英镑,在美国的售价是9.99美元。尽管美国离龙虾产地更近,但Pret龙虾卷在那里的售价比英国贵。
关键词 龙虾 三明治 上班族 英镑 美元 PRE 美国
Polestar Precept 认领
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作者 纳森 《汽车之友》 2020年第7期16-17,共2页
2020年2月25日,Polestar极星品牌为我们呈现了一场关于"未来"的讨论。什么是未来?又或者说,什么是极星的未来?他们给出的答案,便是这台Polestar Precept。有别于"概念车/Concept Car"这一为人所熟知的定义,极星品... 2020年2月25日,Polestar极星品牌为我们呈现了一场关于"未来"的讨论。什么是未来?又或者说,什么是极星的未来?他们给出的答案,便是这台Polestar Precept。有别于"概念车/Concept Car"这一为人所熟知的定义,极星品牌此次推出的Polestar Precept,更像是历经Polestar 1,2两代产品之后,品牌方对于未来走向的清晰把握。简而言之,以Precept而命名的全新产品,是极星作为独立品牌,首次以其独特设计语言,诠释品牌价值的重要里程碑。 展开更多
关键词 全新产品 概念车 品牌价值 极星 未来走向 PRE
A study of medication rules of traditional Chinese medicine in the treatment of pre diabetes based on data mining 认领
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作者 Ji-Ya Sun Qiong-Yang Zhou +4 位作者 Chao Cheng Zhi-Heng Zhao Gui-Tong Zhou Yi-Hua Fan Xin-Ju Li 《TMR医学数据挖掘》 2020年第4期166-176,共11页
Background:To summarize the concerted application and prescription rules of traditional Chinese medicine in the treatment of pre diabetes.Methods:Microsoft Excel 2010 was used to summarize the categories,nature,flavou... Background:To summarize the concerted application and prescription rules of traditional Chinese medicine in the treatment of pre diabetes.Methods:Microsoft Excel 2010 was used to summarize the categories,nature,flavour and channel tropism of drugs.The cluster analysis of high-frequency drugs was carried out by SPSS 22.0,and the association rules of high-frequency drugs were analyzed by Apriori algorithm provided by SPSS modeler 14.0.Results:One hundred and forty-six references were included,including 153 prescriptions and 131 drugs.Their frequency of use is listed in the following order.The top 3 categories of drugs were“Tonifying,Heat-Clearing”,diuresis and“Diffusing Dampness”drugs.The top 5 drugs were Huangqi(Astragali radix),Fuling(Poria),Huanglian(Coptidis rhizoma),Shanyao(Dioscoreae rhizoma),Gegen(Puerariae lobatae radix).The top 3 channel tropism of drugs were spleen,stomach and lung.The top 3 nature of drugs were cold,warm and calm.The top 3 flavour of drugs were sweet,bitter and pungent.The cluster analysis of high-frequency drugs showed that it could be classified into 4 categories:“Benefiting Qi”for promoting production of fluid,“Clearing Heat”and“Eliminating Dampness”,“Nourishing Yin”and“Clearing Heat”,and“Invigorating Spleen”for“Diffusing Dampness”.The results of association rule analysis showed that the combination with the highest degree of confidence and support was Poria-Chenpi(Citri reticulatae pericarpium)-Banxia(Pinelliae rhizoma)-Baizhu(Atractylodis macrocephalae rhizoma)and the combination with the highest frequency was Astragali radix-Puerariae lobatae radix.Conclusion:The pre diabetes is due to deficiency.The disease location is spleen and stomach and the pathological factor is phlegm-damp,that is why benefiting qi and invigorating spleen is regarded as the key link of clinical treatment. 展开更多
关键词 Pre diabetes Traditional Chinese medicine Medication rules Data mining
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小学道德与法治课堂深度学习PRE教学模式初探——以统编版六年级下册《地球——我们的家园》为例 认领
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作者 郭岚静 《新教师》 2020年第8期68-69,共2页
当前的小学道德与法治教学,总体上呈现良好的发展态势。但由于小学道德与法治课程开创时间较短,教师对这门课程的教学经验略显不足,在具体的教学中还存在诸如教材的解读较为浅显、操作性不强、教学停留在表面化等现象。可以说,现在的小... 当前的小学道德与法治教学,总体上呈现良好的发展态势。但由于小学道德与法治课程开创时间较短,教师对这门课程的教学经验略显不足,在具体的教学中还存在诸如教材的解读较为浅显、操作性不强、教学停留在表面化等现象。可以说,现在的小学道德与法治课堂呼唤促进学生深度学习的教学模式。本文以统编版六年级下册《地球——我们的家园》一课为例,对小学道德与法治课堂深度学习PRE教学模式进行初探,以供参考。 展开更多
关键词 深度学习 小学道德与法治 道德与法治课程 课堂深度 教学模式 PRE 发展态势 六年级
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回采面超前应力破坏区联合支护措施 认领
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作者 朱晓宁 《山东煤炭科技》 2020年第4期83-84,87,90共4页
基于小峪煤矿8202工作面在450~540m段位于工作面前方20m范围内回风顺槽侧顶板出现严重破碎、冒落现象,合理分析了顶板破碎原因,根据实际生产情况提出了“施工卸压孔+注浆+双梁联锁钢棚”联合措施进行顶板维护,减少了顶板破碎现象,顶板... 基于小峪煤矿8202工作面在450~540m段位于工作面前方20m范围内回风顺槽侧顶板出现严重破碎、冒落现象,合理分析了顶板破碎原因,根据实际生产情况提出了“施工卸压孔+注浆+双梁联锁钢棚”联合措施进行顶板维护,减少了顶板破碎现象,顶板下沉量控制在0.15m以下,保证了工作面安全高效回采。 展开更多
关键词 综采 超前 支护
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乙型肝炎病毒PreS/S基因突变的研究进展 认领
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作者 顾红芳 梁晓华 邓雪莲 《中国输血杂志》 CAS 2020年第1期89-93,共5页
乙型肝炎病毒(Hepatitis B virus, HBV)PreS/S基因突变十分常见,可由内因即病毒和宿主之间免疫反应导致,也可由免疫预防或者抗病毒治疗等外因引发。Pre-S区以缺失突变为主,S区以"a"抗原决定簇的点突变常见。此区域的突变可导... 乙型肝炎病毒(Hepatitis B virus, HBV)PreS/S基因突变十分常见,可由内因即病毒和宿主之间免疫反应导致,也可由免疫预防或者抗病毒治疗等外因引发。Pre-S区以缺失突变为主,S区以"a"抗原决定簇的点突变常见。此区域的突变可导致乙型肝炎病毒表面抗原(HBV surface antigen, HBsAg)和相关蛋白的合成、分泌障碍,具有重要的病理生理意义和临床影响。研究显示PreS/S基因突变与某些肝脏疾病发生及进展存在着明显的相关性;可使HBsAg的抗原性发生改变,因不被抗-HBs识别而导致HBsAg检测失败和已免疫者发生突破性HBV感染;是隐匿性乙型肝炎病毒感染(Occult HBV infection, OBI)的重要发生机制之一,而OBI是当前血液筛查的主要风险来源。目前,PreS/S基因突变研究仍缺乏更为广泛的长期监控数据,这是评估PreS/S基因突变实际影响的重要制约因素。 展开更多
关键词 乙型肝炎病毒 PRE S/S基因 基因突变
Adsorption of 17β-estradiol from aqueous solution by raw and direct/pre/post-KOH treated lotus seedpod biochar 认领
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作者 Ni Liu Yunguo Liu +7 位作者 Guangming Zeng Jilai Gong Xiaofei Tan Jun Wen Shaobo Liu Luhua Jiang Meifang Li Zhihong Yin 《环境科学学报:英文版》 SCIE EI CAS CSCD 2020年第1期10-23,共14页
Five biochars derived from lotus seedpod(LSP)were applied to examine and compare the adsorption capacity of 17β-estradiol(E2)from aqueous solution.The effect of KOH activation and the order of activation steps on mat... Five biochars derived from lotus seedpod(LSP)were applied to examine and compare the adsorption capacity of 17β-estradiol(E2)from aqueous solution.The effect of KOH activation and the order of activation steps on material properties were discussed.The effect of contact time,initial concentration,p H,ionic strength and humic acid on E2 adsorption were investigated in a batch adsorption process.Experimental results demonstrated that the pseudo second-order model fitted the experimental data best and that adsorption equilibrium was reached within 20 hr.The efficiency of E2 removal increased with increasing E2 concentration and decreased with the increase of ionic strength.E2 adsorption on LSP-derived biochar(BCs)was influenced little by humic acid,and slightly affected by the solution p H when its value ranged from 4.0 to 9.0,but considerably affected at p H 10.0.Low environmental temperature is favorable for E2 adsorption.Chemisorption,π–πinteractions,monolayer adsorption and electrostatic interaction are the possible adsorption mechanisms.Comparative studies indicated that KOH activation and the order of activation steps had significant impacts on the material.Post-treated biochar exhibited better adsorption capacity for E2 than direct treated,pretreated,and raw LSP biochar.Pyrolyzed biochar at higher temperature improved E2 removal.The excellent performance of BCs in removing E2 suggested that BCs have potential in E2 treatment and that the biochar directly treated by KOH would be a good choice for the treatment of E2 in aqueous solution,with its advantages of good efficiency and simple technology. 展开更多
关键词 17Β-ESTRADIOL Lotus seedpod derived BIOCHAR Activation order Pre-or POST-TREATMENT ADSORPTION
英语前缀pro-和前缀pre-的语义及构词对比研究 认领
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作者 褚轶男 黄凤鸰(指导) 《海外英语》 2020年第3期218-219,252共3页
该文基于英国国家语料库,对前缀pro-以及前缀pre-进行语义词源上的对比研究,以及两者所构成词的词性的对比。研究发现,前缀pro-拥有更多的语义。另外,前缀pro-所构成词的词汇往往有一个动作的倾向性,而前缀pre-构成的词往往在时间有一... 该文基于英国国家语料库,对前缀pro-以及前缀pre-进行语义词源上的对比研究,以及两者所构成词的词性的对比。研究发现,前缀pro-拥有更多的语义。另外,前缀pro-所构成词的词汇往往有一个动作的倾向性,而前缀pre-构成的词往往在时间有一个提前。在语义相同的情况下,两个前缀均表示"before"时,pre-构成词的词性更多;而在前缀表示"front"时,两者相反,前缀pro-构成词的词性更多;在表示"in front of"时,两者构成词词性均为动词,且词汇量较少。 展开更多
关键词 前缀 pro- pre-
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Geodynamic Development of Eurasian Active Margin during Closing of Thetys Ocean, Depending on the Scale of Mantle-Crustal Sources Influence at Pre- and Post-collision Settings, Controlled by Geological and Geochemical Indicators 认领
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作者 Vladimir I.Gugushvili 《环境科学与工程:B》 2020年第6期248-260,共13页
Phanerozoic geodynamic evolution development of Tethys Ocean,its collision and closing,revealed at the Eurasian active margin in pre-and post-collision stages during convergence of Afro-Arabian and Eurasian continents... Phanerozoic geodynamic evolution development of Tethys Ocean,its collision and closing,revealed at the Eurasian active margin in pre-and post-collision stages during convergence of Afro-Arabian and Eurasian continents.Subduction of oceanic slab under continental margin revealed in steady state subduction and steepening of subducting slab provoked the incursion of mantle diapir.The steady state subduction is related with island arc setting whereas steepening provoked incursion of mantle diaper interarc-backarc and minor ocean settings.They are controlled by geological indicators—volcagenic,petrochemical,geochemical,tectonic and metallogenic.Each of them is determined by scale of mantle-crustal influence,controlled by intensity and level of mantle diapir incursion in the crust rising from interarc-backarc to minor oceanic setting.The island arc setting is characterized by blocking,which as others by extension of rifting(interarc-backarc)caused spreading out from zone of volcanic activity and mineralization sialic crusts,whereas minor ocean setting caused by spreading out from zone of volcanic activity and mineralization sialic and basaltic crusts.So mantle crustal influence rising from island arc to minor ocean settings controlled type of volcanism and mineralization in pre-collision development.At the closing of ocean occurred the precollision setting which is transferred in post-collision revealed in orogenesis.It is divided in two stages.The first initial stage occurred in penetration hot fluids from the mantle in sialic crust smelted from in granitoid melt and leached the gold and trace melts Sb,W,Mg and Hg from sialic crust.The latter are geochemical indicators of post-collision setting.The second final stage revealed in shoshonite-basalt volcanism activity occurred with penetrated mantle material into deep volcanic chambers and characterized with increasing of mantle influence than initial stage of post-collision activity. 展开更多
关键词 Pre- and POST-COLLISION SETTINGS crustal-mantle SOURCES GEOLOGICAL indicators
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Pre-Hospital Management of Craniocerebral Trauma in South Saharan Africa: Cotonou Experience 认领
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作者 Abd El Kader Moumouni Essossinam Kpelao +5 位作者 Holden Olatoundji Fadigba Agbeko Achille Doleagbenou Ibrahima Berete Dabou Abiba Tamou Tabe Emile Mensah Martin Chobli 《现代神经外科学进展(英文)》 2019年第3期221-226,共6页
The management of craniocerebral trauma begins at the site of the accident. This is one of the diseases for which pre-hospital care is well codified. The objective of this study is to report the experience of the Emer... The management of craniocerebral trauma begins at the site of the accident. This is one of the diseases for which pre-hospital care is well codified. The objective of this study is to report the experience of the Emergency Aid Medical Service (EMAS) of BENIN in the pre-hospital management of craniocerebral trauma. 146 head injuries were cared for. 116 were male. The mean age was 32 years with extremes ranging from 2 to 77 years. Etiology in 68% of patients was a public road accident. And the request for the use of the EMAS was made by highway users for 41% of the injuries. About 5.5% were severe cranio-brain injuries, more than 75% of which had died in intensive care. In 77% of the EMAS interventions, there was an intensive care physician in the team. 34 wounded had been transported in a vacuum mattress. The rigid cervical collar was used in 8 major traumas. All the wounded were transported by ambulance. The duration of hospitalization varied from a few hours in the emergency department to 90 days in the hospital ward. 9 patients died. One of them, who died in an ambulance, was a woman. The prehospital medical care of head trauma in BENIN is still progressing. 展开更多
关键词 Emergency CRANIOCEREBRAL AFRICA South-Sahara Pre HOSPITAL MANAGEMENT
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A Hydro PV Hybrid System for the Laranjeiras Dam (in Southern Brazil) Operating with Storage Capacity in the Water Reservoir 认领
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作者 Gabriel Vasco Jones S. Silva +3 位作者 Fausto A. Canales Alexandre Beluco José de Souza Elton G. Rossini 《智能电网与可再生能源(英文)》 2019年第4期83-97,共15页
Seasonal variability coupled with the intermittency of renewable energy sources makes reservoir hydroelectric plants an interesting option to consider in hybrid energy systems, especially in cases of dams that have no... Seasonal variability coupled with the intermittency of renewable energy sources makes reservoir hydroelectric plants an interesting option to consider in hybrid energy systems, especially in cases of dams that have not been completed or have been abandoned and which still have some potential for reuse. The Laranjeiras dam was completed in the 1960s and the original project for hydroelectric power generation was not completed, made impossible by economic changes during the construction years. A recent study proposed the implementation of a hydroelectric photovoltaic hybrid system with lower horsepower to allow the dam to be made useful again. This paper presents the results of the computational simulations with the software Homer, considering the operation of the hydroelectric component (of the proposed hybrid system) with reservoir, playing the role of energy storage device when the production exceeds the demand at a given moment, reducing the loss of energy due to unavailability of demand. The study suggested to implement a hydroelectric power plant with power house at the base of the dam that has a height of 20 m, operating at a minimum flow of 9171 L/s, with reservoir operating as a device for energy storage, operating with a photovoltaic system of 360 kW, and a power limit for the purchase of energy from the grid equal to 200 kW, providing consumer loads up to 40 MWh per day, with cost of energy equal to US$0.021 per kWh and a capital cost of US$3285.617. 展开更多
关键词 Hybrid Systems ENERGETIC Complementarity PV Modules on FLOATING Structures Pre FEASIBILITY Study Software HOMER
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不同HBV基因型慢性乙型肝炎患者的血清HBV DNA、PreS1、HBeAg检测结果分析 认领 被引量:2
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作者 吴湃 吴坤河 +2 位作者 刘海燕 张斗星 胡安群 《分子诊断与治疗杂志》 2019年第6期495-498,507共5页
目的调查安徽安庆地区慢性乙型病毒性肝炎患者所感染的乙型肝炎病毒(HBV)的基因型构成,并探讨不同HBV基因型患者的血清HBV DNA、PreS1、HBeAg检测结果及临床价值,为乙型病毒性肝炎患者的个体化医疗提供依据。方法选取慢性乙肝患者共226... 目的调查安徽安庆地区慢性乙型病毒性肝炎患者所感染的乙型肝炎病毒(HBV)的基因型构成,并探讨不同HBV基因型患者的血清HBV DNA、PreS1、HBeAg检测结果及临床价值,为乙型病毒性肝炎患者的个体化医疗提供依据。方法选取慢性乙肝患者共226例,采用巢式PCR技术对其进行基因分型检测,采用实时荧光定量聚合酶链反应法(RT PCR)检测患者血清HBV DNA,用酶联免疫吸附分析法(ELISA)检测血清PreSl抗原与HBeAg。结果在调查的乙型病毒性肝炎患者中,以B基因型(占58.0%)与C基因型(占41.1%)HBV感染为主。B基因型患者血液中HBV DNA阳性率(57.2%)与C型患者(63.4%)没有统计学差异;B基因型患者血液中PreS1抗原阳性率(48.1%)与C型患者(48.4%)也没有明显差异;C基因型HBV感染的患者血液HBeAg阳性率(46.2%)高于B基因型患者(32.1%)。结论安徽安庆地区在慢性乙肝的卫生防治策略上,应重点关注B、C型基因型HBV感染的防治。而C基因型HBV感染患者具有高HBeAg阳性率,应采取更积极、有效干预措施。 展开更多
关键词 慢性乙型病毒性肝炎 HBV基因型 HBV DNA PRE S1 HBEAG
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深耕下沉市场家政蓝海,海格管家获千万级Pre-A轮融资 认领
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《家庭服务》 2019年第7期50-51,共2页
2019年6月,专业家政服务提供商海格管家宣布完成千万级人民币Pre-A轮融资,投资方未披露。海格管家CEO董凡表示,此次融资极为关键,资金将用于系统升级、产品迭代、人员培训以及项目市场的拓展。海格管家创立于2015年,目前是一家专注于昆... 2019年6月,专业家政服务提供商海格管家宣布完成千万级人民币Pre-A轮融资,投资方未披露。海格管家CEO董凡表示,此次融资极为关键,资金将用于系统升级、产品迭代、人员培训以及项目市场的拓展。海格管家创立于2015年,目前是一家专注于昆明市场的专业家政服务提供商,主要业务是提供居家保洁服务,产品包括日常居家保洁服务'轻洁家'和新房开荒保洁服务'新家净'。 展开更多
关键词 家政服务行业 Pre-A 家政市场
Pre-and post-selected measurements with coupling-strength-dependent modulation 认领
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作者 李兆雪 邱疆冬 +5 位作者 谢林果 罗兰 刘雄 张志友 任昌亮 杜惊雷 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第3期135-140,共6页
Pre-and post-selected(PPS) measurement, especially the weak PPS measurement, has been proved to be a useful tool for measuring extremely tiny physical parameters. However, it is difficult to retain both the attainable... Pre-and post-selected(PPS) measurement, especially the weak PPS measurement, has been proved to be a useful tool for measuring extremely tiny physical parameters. However, it is difficult to retain both the attainable highest measurement sensitivity and precision with the increase of the parameter to be measured. Here, a modulated PPS measurement scheme based on coupling-strength-dependent modulation is presented with the highest sensitivity and precision retained for an arbitrary coupling strength. This idea is demonstrated by comparing the modulated PPS measurement scheme with the standard PPS measurement scheme in the case of unbalanced input meter. By using the Fisher information metric, we derive the optimal pre-and post-selected states, as well as the optimal coupling-strength-dependent modulation without any restriction on the coupling strength. We also give the specific strategy of performing the modulated PPS measurement scheme, which may promote practical application of this scheme in precision metrology. 展开更多
关键词 MODULATED pre-and post-selected MEASUREMENTS Fisher information metric unbalanced input METER
杂多一次漏报中雪的卫星资料分析 认领
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作者 桓姝琦 赵敏 李云霞 《青海气象》 2019年第3期23-26,共4页
利用MICAPS中提供的常规资料、FY—2E标称格式数据资料以及一些卫星资料反演的大气产品,对2017年11月30日21—22时杂多漏报中雪天气过程进行分析。通过MICAPS常规资料的分析可以把握环流背景;利用卫星天气应用平台(SWAP)对FY—2E标称格... 利用MICAPS中提供的常规资料、FY—2E标称格式数据资料以及一些卫星资料反演的大气产品,对2017年11月30日21—22时杂多漏报中雪天气过程进行分析。通过MICAPS常规资料的分析可以把握环流背景;利用卫星天气应用平台(SWAP)对FY—2E标称格式数据资料的分析进行对流云的追踪判识及外推,对预报员判断对流云移动方向有较好的指导;而卫星资料反演的大气产品,如云区湿度廓线(HPF)可以估计降水云系所在地点的水汽垂直廓线,降水估计产品(PRE)可以估判地面降水为气象服务提供参考。卫星资料在天气预报中的应用可以一定程度上弥补玉树等高原地区自动站资料缺乏,为今后对流天气的预报服务提供一种新的思路。 展开更多
关键词 FY—2E SWAP系统 对流追踪 HPF PRE
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从苏联起飞,归来时已是俄罗斯——俄罗斯航天英雄谢尔盖·克里卡廖夫传奇飞行生涯 认领
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作者 王永生(编译) 黄冉(编译) 《载人航天信息》 2019年第4期45-47,16共4页
2018年8月7日谢尔盖·克里卡廖夫(Сеpreй Кpикалёв)已年满60岁。这位先后获得“苏联英雄”和“俄罗斯联邦英雄”称号的俄罗斯航天员,在相当一段时间保持了太空飞行总时间的世界记录,在其传奇的飞行生涯中还有许多精彩的... 2018年8月7日谢尔盖·克里卡廖夫(Сеpreй Кpикалёв)已年满60岁。这位先后获得“苏联英雄”和“俄罗斯联邦英雄”称号的俄罗斯航天员,在相当一段时间保持了太空飞行总时间的世界记录,在其传奇的飞行生涯中还有许多精彩的瞬间。谢尔盖·克里卡廖夫,1958年8月27日出生于列宁格勒(现为圣彼得堡),1975年高中毕业。 展开更多
关键词 俄罗斯联邦 太空飞行 航天员 谢尔 苏联 起飞 圣彼得堡 PRE
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Role of pre-vertical compression in deformation behavior of Mg alloy AZ31B during super-high reduction hot rolling process 认领 被引量:2
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作者 Weitao Jia Qichi Le +3 位作者 Yan Tang Yunpeng Ding Fangkun Ning Jianzhong Cui 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2018年第11期2069-2083,共15页
Mg 合金 AZ31B 盘子被每超高频率的减小跟随的通行证和 pre 垂直的压缩的与不同厚度减小的热滚动处理热滚动(PVCR ) 分别地。微观结构进化,滚动 formability 变化和机械回答被调查。当减小每通行证增加了,数字砍向卷方向偏斜的乐队增... Mg 合金 AZ31B 盘子被每超高频率的减小跟随的通行证和 pre 垂直的压缩的与不同厚度减小的热滚动处理热滚动(PVCR ) 分别地。微观结构进化,滚动 formability 变化和机械回答被调查。当减小每通行证增加了,数字砍向卷方向偏斜的乐队增加了,导致容易的裂缝开始在并且在乐队附近。与每通行证增加减小直到 80% , twinning 和导致双胞胎的动态再结晶(DRX ) 在 350 ? 统治了边材料的变丑 ??  ?????????????  ??????????? 吗?? 展开更多
关键词 AZ31B PRE 高频率 滚动 合金 压缩 垂直 动态再结晶
Evolutionary status of T Tauri stars 认领
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作者 Olga Eretnova Alexander Dudorov 《天文和天体物理学研究:英文版》 SCIE CAS CSCD 2018年第8期103-110,共8页
关键词 进化地位 主角 进化模型 TTS 绝对温标 PRE 二进制 轨道
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