Solar irradiation can efficiently promote the kinetics of the oxygen evolution reaction(OER)during water splitting,where heterojunction catalysts exhibit excellent photoresponsive properties.However,insights into the ...Solar irradiation can efficiently promote the kinetics of the oxygen evolution reaction(OER)during water splitting,where heterojunction catalysts exhibit excellent photoresponsive properties.However,insights into the origins of photoassisted OER catalysis remain unclear,especially the interfaced promotion under convergent solar irradiation(CSI).Herein,novel allotropic Co_(5.47)N/CoN heterojunctions were synthesized,and corresponding OER mechanisms under CSI were comprehensively uncovered from physical and chemical aspects using the in situ Raman technique and electrochemical cyclic voltammetry method.Our results provide a unique mechanism where high-energy UV light promotes the Co^(3+/4+)conversion process in addition to the ordinary photoelectric effect excitation of the Co^(2+)material.Importantly,visible light under CSI can produce a photothermal effect for Co^(2+)excitation and Co^(3+/4+)conversion,which promotes the OER significantly more than the usual photoelectric effect.As a result,Co_(5.47)N/CoN(containing 28%CoN)obtained 317.9%OER enhancement,which provides a pathway for constructing excellent OER catalysts.展开更多
The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantl...The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been weak.Based on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different strata.The gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary environment.With increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to inorganic.The origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and mantle-derived.The shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic gas.Furthermore,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived gas.The discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas.展开更多
[Objective] This study aimed to analyze the volatile constituents in Lonicera japonica Thunb. from different origins. [Method] HP-5MS capillary columns were used and column temperature was controlled by a program. MS ...[Objective] This study aimed to analyze the volatile constituents in Lonicera japonica Thunb. from different origins. [Method] HP-5MS capillary columns were used and column temperature was controlled by a program. MS analysis was performed with EI and quadruple mass analyzer. The volatile constituents in L. japonica Thunb. were identified by NIST02 and Wiley275 libraries, and their relative contents were determined with chromatographic peak area normalization method. [Result] According to GC-MS total ion-current chromatograms, 35 volatile constituents were identified in L. japonica Thunb. from Guangxi Zhuang Autonomous Region, mainly including methyl linolenate, n-hexadecanoic acid and ζ-muurolene; 18 volatile constituents were identified in L. japonica Thunb. from Hunan Province, mainly including n-hexadecanoic acid, linoleic acid and α-curcumene. [Conclusion] Main volatile constituents in L. japonica Thunb. from two different origins varied significantly.展开更多
Metallic iron nanoparticles(npFe0)are widespread on the Moon,and their accumulation changes the optical spectra of the lunar surface over time.How the surface color changes largely depends on the size of npFe0:smaller...Metallic iron nanoparticles(npFe0)are widespread on the Moon,and their accumulation changes the optical spectra of the lunar surface over time.How the surface color changes largely depends on the size of npFe0:smaller npFe0 reddens the reflectance spectra,while larger npFe0 causes darkening.The resultant color variations greatly complicate remote sensing studies,posing long-term puzzles to astronomers.展开更多
1.Introduction The Hengduan Mountains region(HDM)in southwest China,one of the earth's 34 biodiversity hotspots,is characterized by its unique geology,dramatic topography,a climate where snow and below freezing te...1.Introduction The Hengduan Mountains region(HDM)in southwest China,one of the earth's 34 biodiversity hotspots,is characterized by its unique geology,dramatic topography,a climate where snow and below freezing temperatures can occur on any day of the year,by its location at elevations averaging between(1400e)2000 and4500(e5300)meters above sea level(m a.s.l.),and by one of展开更多
The ongoing pandemic of coronavirus disease 2019 (COVID-19), caused by infection with human coronavirus 2019 (HCoV-19/SARS-CoV-2/2019-nCoV), is a global threat to the human population. Here, we briefly summarize the a...The ongoing pandemic of coronavirus disease 2019 (COVID-19), caused by infection with human coronavirus 2019 (HCoV-19/SARS-CoV-2/2019-nCoV), is a global threat to the human population. Here, we briefly summarize the available data for the zoonotic origins of HCoV-19, with reference to the other two epidemics of highly virulent coronaviruses, SARSCoV and MERS-CoV, which cause severe pneumonia in humans. We propose to intensify future efforts for tracing the origins of HCoV-19, which is a very important scientific question for the control and prevention of the pandemic.展开更多
[Objective] To lay the foundation for the classification and breeding of Litchi (Litchi chinensis Sonn.) through RAPD (Random Amplification Polymorphic DNA) analysis of the Litchi cultivars with different origins....[Objective] To lay the foundation for the classification and breeding of Litchi (Litchi chinensis Sonn.) through RAPD (Random Amplification Polymorphic DNA) analysis of the Litchi cultivars with different origins. [Method] 5 Litchi cultivars from Sichuan, Guangxi, Guangdong, Fujian and Hainan were used as experimental materials to extract genomic DNA by modified CTAB method. Twenty primers with well reproducibility were randomly selected to conduct RAPD amplification to analyze the polymorphism and genetic relationship of the five cultivars. [Result] The polymor- phism of the five Litchi cultivars was 61%, with the similarity coefficient of 0.571 4- 0.803 6. The similarity coefficient of those from Guangdong and Guangxi was the largest of 0.803 6, and from Sichuan and Hainan was the lowest of 0.571 4. The resolution and production of RAPD was significantly improved by appropriately pro- longing the ramp time from annealing to extension to 0.3℃/s. [Conclusion] This study provided theoretical basis for the classification and breeding of Litchi.展开更多
In the southwestern Yellow Sea there is a low-salinity and turbid coastal water,the Subei Coastal Water(SCW).The origins of freshwater contents and thus the dissolved terrigenous nutrients in the SCW have been debat...In the southwestern Yellow Sea there is a low-salinity and turbid coastal water,the Subei Coastal Water(SCW).The origins of freshwater contents and thus the dissolved terrigenous nutrients in the SCW have been debated for decades.In this study,we used a well-validated numerical model to quantify the contributions of multiple rivers,i.e.,the Changjiang River in the south and the multiple Subei local rivers(SLRs) in the north,in forming this yearround low-salinity coastal water.It is found that the freshwater contents in the SCW is dominated by the Changjiang River south of 33.5°N,by the SLRs north of 34.5°N,and by both sources in 33.5°–34.5°N.Overall,the Changjiang River contributes ~70% in the dry season and ~80% in the wet season of the total freshwater contents in the SCW,respectively.Dynamics driving the Changjiang River Plume to flow northward is the tidal residual current,which can even overwhelm the wind effects in winter seasons.The residual currents turn offshore near the Old Yellow River Delta(OYRD) by the collision of the two tidal wave systems,which transport the freshwater from both sources into the interior Yellow Sea.Water age experiments show that it takes 50–150 d for the Changjiang River Plume to reach the SCW in the spring and summer seasons,thus there is a 2-month lag between the maximum freshwater content in SCW and the peak Changjiang River discharge.In the winter and autumn seasons,the low salinity in inner SCW is the remnant Changjiang River diluted water arrived in the previous seasons.展开更多
Pediatric origin of cancer stem cell hypothesis holds great promise and potential in adult cancer treatment, however; the road to innovation is full of obstacles as there are plenty of questions left unanswered. First...Pediatric origin of cancer stem cell hypothesis holds great promise and potential in adult cancer treatment, however; the road to innovation is full of obstacles as there are plenty of questions left unanswered. First, the key question is to characterize the nature of such stem cells (concept). Second, the quantitative imaging of pediatric stem cells should be implemented(technology). Conceptually, pediatric stem cell origins of adult cancer are based on the notion that plasticity in early life developmental programming evolves local environments to cancer. Technologically, such imaging in children is lacking as all imaging is designed for adult patients. We postulate that the need for quantitative imaging to measure space-time changes of plasticity in early life developmental programming in children may trigger research and development of the imaging technology. Such quantitative imaging of pediatric origin of adulthood cancer will help develop a spatiotemporal monitoring system to determine cancer initiation and progression. Clinical validation of such speculative hypothesis-that cancer originates in a pediatric environment-will help implement a wait-andwatch strategy for cancer treatment.展开更多
Sexism in the English Language is the reflector of a social sexism. The thesis is not only to discuss phenomena of sexism in English in terms of morphology, syntax and semantics, but also to focus on the origins and p...Sexism in the English Language is the reflector of a social sexism. The thesis is not only to discuss phenomena of sexism in English in terms of morphology, syntax and semantics, but also to focus on the origins and point out the ways of desexism.展开更多
The severe acute respiratory syndrome COVID-19 was discovered on December 31,2019 in China.Subsequently,many COVID-19 cases were reported in many other countries.However,some positive COVID-19 samples had been reporte...The severe acute respiratory syndrome COVID-19 was discovered on December 31,2019 in China.Subsequently,many COVID-19 cases were reported in many other countries.However,some positive COVID-19 samples had been reported earlier than those officially accepted by health authorities in other countries,such as France and Italy.Thus,it is of great importance to determine the place where SARS-CoV-2 was first transmitted to human.To this end,we analyze genomes of SARS-CoV-2 using k-mer natural vector method and compare the similarities of global SARS-CoV-2 genomes by a new natural metric.Because it is commonly accepted that SARS-CoV-2 is originated from bat coronavirus RaTG13,we only need to determine which SARS-CoV-2 genome sequence has the closest distance to bat coronavirus RaTG13 under our natural metric.From our analysis,SARS-CoV-2 most likely has already existed in other countries such as France,India,Netherland,England and United States before the outbreak at Wuhan,China.展开更多
[Objectives]This study was conducted to clarify the differences of volatile components in fresh fruit of Morinda citrifolia L.from different origins.[Methods]The method of HS-SPME-GC/MS detection was used to determine...[Objectives]This study was conducted to clarify the differences of volatile components in fresh fruit of Morinda citrifolia L.from different origins.[Methods]The method of HS-SPME-GC/MS detection was used to determine the volatile chemical components in fresh fruit of M.citrifolia.[Results]52,52 and 45 volatile components were identified from the fresh fruit of M.citrifolia from Xisha,Wanning and Haikou,respectively.Among them,the number and content of the identified esters were relatively high,mainly methyl caprylate,ethyl caprylate,4-pentenyl caproate,3-methylbuten-2-enyl caprylate,methyl caproate,and ethyl caproate.There were also fatty acids,alcohols,phenols,ketones,aldehydes and other substances.There were 33 common ingredients in the fruit from the three origins,mainly including caprylic acid,caproic acid,capric acid,methyl caprylate,ethyl caprylate,4-pentenyl caproate,3-methylbutene-2-enyl caprylate,methyl caproate,ethyl caproate,methyl caprate and hexyl caproate.[Conclusions]The types and contents of volatile components in fresh fruit of M.citrifolia from different origins were significantly different.展开更多
Solid helium bubbles were directly observed in the helium ion implanted tungsten(W), by different transmission electron microscopy(TEM) techniques at room temperature. The diameters of these solid helium bubbles r...Solid helium bubbles were directly observed in the helium ion implanted tungsten(W), by different transmission electron microscopy(TEM) techniques at room temperature. The diameters of these solid helium bubbles range from1 nm to 8 nm in diameter with the mean bubble size about 3 nm. The selected area electron diffraction(SAED) and fast Fourier transform(FFT) images revealed that solid helium bubbles possess body-centered cubic(bcc) structure with a lattice constant of 0.447 nm. High-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)images further confirmed the existence of helium bubble in tungsten. The present findings provide an atomic level view of the microstructure evolution of helium in the materials, and revealed the existence of solid helium bubbles in materials.展开更多
Various species of Cu.Pb,Zn and Cr in dust of different origins and diameters were studied using Tessler scheme,and the partition law was revealed, The results indicated that superior form of Cu、Pb、 Zn and Cr was bo...Various species of Cu.Pb,Zn and Cr in dust of different origins and diameters were studied using Tessler scheme,and the partition law was revealed, The results indicated that superior form of Cu、Pb、 Zn and Cr was bound to organic master,bound to Fe-Mn oxides,bound to Fe-Mn oxides and residual.So their activity order was Zn>Pb>Cu>Cr.The exchangeable metals bound to carbonates and Fe-Mn oxides of four heary metals in small particles were superior to those in large particles,which illustrated that heavy metals in small paticles were more active and harmful.展开更多
The developmental origins of health and diseases(DOHaD)is a concept stating that adverse intrauterine environments contribute to the health risks of offspring.Since the theory emerged more than 30 years ago,many epide...The developmental origins of health and diseases(DOHaD)is a concept stating that adverse intrauterine environments contribute to the health risks of offspring.Since the theory emerged more than 30 years ago,many epidemiological and animal studies have confirmed that in utero exposure to environmental insults,including hyperglycemia and chemicals,increased the risk of developing noncommunicable diseases(NCDs).These NCDs include metabolic syndrome,type 2 diabetes,and complications such as diabetic cardiomyopathy.Studying the effects of different environmental insults on early embryo development would aid in understanding the underlying mechanisms by which these insults promote NCD development.Embryonic stem cells(ESCs)have also been utilized by researchers to study the DOHaD.ESCs have pluripotent characteristics and can be differentiated into almost every cell lineage;therefore,they are excellent in vitro models for studying early developmental events.More importantly,human ESCs(hESCs)are the best alternative to human embryos for research because of ethical concerns.In this review,we will discuss different maternal conditions associated with DOHaD,focusing on the complications of maternal diabetes.Next,we will review the differentiation protocols developed to generate different cell lineages from hESCs.Additionally,we will review how hESCs are utilized as a model for research into the DOHaD.The effects of environmental insults on hESC differentiation and the possible involvement of epigenetic regulation will be discussed.展开更多
The paper proposes that the four-component structure of political order consists of state, imagination, rule, and accountability whose mental origins are the social brain, theory of mind, the rational brain, and the e...The paper proposes that the four-component structure of political order consists of state, imagination, rule, and accountability whose mental origins are the social brain, theory of mind, the rational brain, and the empirical brain, respectively. The rational brain and the empirical brain are from the thinking brain. This paper posits that in the evolution of political order, the main function of political order is to pacify changed social structure derived from technological revolution. Therefore, the four technological revolutions (the Upper Paleolithic, Agricultural-Bronze, Iron, and Industrial Revolutions) produce the four changed social structures (linked bands, tribe, mega empire, and modern nation, respectively) whose internal conflicts are pacified by the four political revolutions (the imaginative, hierarchical, thinking, bottom-up political revolutions, respectively) to form the four politics (the imaginative egalitarianism, decentralized hierarchical tribalism, centralized top-down thinking, and multilateral bottom-up thinking politics, respectively). In the competitive West originated from Greece and Middle East, the rule of law is the rational rule of competition among competitors, and the accountability of election is the empirical accountability of competition among competitors. In the cooperative East originated from India and China, the rule of relation is the rational rule of cooperation among kin-friends, and the accountability of professional qualification is the empirical accountability of cooperation among kin-friends. For political order, the two viable politics are competitive liberal democracy based on liberty and cooperative well-off democracy (well-off socialism) based on wellbeing. The direction of political order is middle democracy between liberal democracy and well-off democracy based on the multilateral bottom-up thinking politics.展开更多
With the development of the rhetoric study from the origins in ancient Athens and The Rhetoric of Aristotle to the formation of modern Communication Study at the beginning of the twentieth century,the Rhetoric Study c...With the development of the rhetoric study from the origins in ancient Athens and The Rhetoric of Aristotle to the formation of modern Communication Study at the beginning of the twentieth century,the Rhetoric Study changed in dynamic and its concepts and theories merged and formed the foundations of Communication Study which focused on personal communication and speech rhetoric skills at that time.At the beginning of the twentieth century,although the Neo-Aristotelian rhetorical scholars from classic rhetoric approach created methodologies and enriched the content of Communication Study under the influence of humanistic study and social science study,but the Communication discipline was still in the embarrassing position.During World War I and World War II,most scholars with backgrounds of social science,history and anthropology carried out the studies of propaganda wars and the message disseminating,and explored the military powers and governments’access to the media and developed serial communication modes from the social science perspective,which laid the foundation for Communication discipline in the academic field.The author analyzed the Rhetoric and Social Science origins of Communication study in Boxing Plato’s Shadow:an Introduction to the Study of Human Communication,which is beneficial and helpful to understand the academic origins of Communication study and its cross-disciplined and embarrassing positions.展开更多
Uyghur medicine refers to the traditional medicine of the people residing in the oases of the Taklamakan desert in the North-West corner of modern China.Due to historical and geographical reasons,the ancestors of the ...Uyghur medicine refers to the traditional medicine of the people residing in the oases of the Taklamakan desert in the North-West corner of modern China.Due to historical and geographical reasons,the ancestors of the modern Uyghurs had extensive contact with Greco-Roman civilization even beginning in the 4th century BCE,and continuing with different extent until the 6th century CE.Thus,the knowledge of Greek humoral medicine spread to the Uyghur regions.When Arab-Persian medicine arrived along with Islam in the 10th century,it met both Buddhist medicine and the developed folk medicine.In this paper,we argue that“Greco-Roman”,“Arab-Persian”and“Uyghur”medicines are all of essentially the same system under holistic humoral medicine.We further assert that“Traditional European Medicine”is based on the same tradition,and,while it was discarded in the West,it has been substantially preserved by the Uyghurs.We also consider the implications of making the two millennial tradition of Uyghur medicine the object of modern scientific research in China.展开更多
Honey is a product of the elaboration of flower nectar by bees. The general features and elemental composition of honey depend on its botanical origin. In this study, five color parameters (L*: lightness, a*: red...Honey is a product of the elaboration of flower nectar by bees. The general features and elemental composition of honey depend on its botanical origin. In this study, five color parameters (L*: lightness, a*: red color, b*: yellow color, C*ab and hab) and five elements (Na, K, Mg, Ca and Zn) were determined and related with 91 Thai honey samples. The origins of four botanic types of (1) longan flower (Dimocarpus sp.), (2) lynchee flower (Litchi sp.), (3) sunflower (Helianthus sp.) and (4) wild flower (Eupatorium sp.) using principle component analysis (PCA). The results showed that five color parameters and five metal contents related with the Thai botanic origins of the honeys using principle component analysis (PCA). Six major indicators of PC i (variance is 44.33%) from three color parameters are L*(-0.926), a*(0.927) and hue or hab (0.824) and from three metal contents are K(0.833), Ca(0.816) and Mg(0.595). Two minor indicators of PC2 (variance is 21.58%) from color parameters are b*(-0.934) and Chroma or C*ab (-0.834). Two indicators of PC3 (%variance is 12.47%) from contents of Na (-0.722) and Zn (0.704). Thai Lynchee (C) flower honeys classified using both six parameters in PC 1 and two color parameters in PC2. Thai longan flower (G) honeys classified using the contents of Zn and Na in PC3 parameters. Thai sunflower (S) honeys classified using two color parameters in PC2. Thai wild flower (W) honeys classified using the metal contents of K in PC 1 parameter, Zn and Na in PC3 parameters.展开更多
English Allusions are the unique and fixed expressions which mostly derive from the Western myths, legends, fables, literature and Western histories. They are crystallization of language and culture and closely relate...English Allusions are the unique and fixed expressions which mostly derive from the Western myths, legends, fables, literature and Western histories. They are crystallization of language and culture and closely related with cultural traditions. English Allusions have profound meaning although their forms are rather concise and terse. In daily communication, we always use allusions consciously or unconsciously. But the Chinese translation of English Allusions is a hard task for translators for their hidden and cultural background meaning is not as simple as their form. Therefore, this paper explores the origins and the corresponding translation of English allusions. It proposes three translation strategies in English allusion translation, aiming to help target readers accept the English allusions more easily and better understand Western culture through the use of English allusions.展开更多
基金supported by the National Natural Science Foundation of China(No.51872068)the Graduate Innovation Project of Harbin Normal University(No.HSDBSCX2021-12 and HSDSSCX2022-51)+3 种基金the Postgraduate Education and Teaching Reform Project of Harbin Normal Universitythe Joint Guidance Project of the Natural Science Foundation of Heilongjiang Province,China(No.LH2022E093)the Heilongjiang Province Col ege students innovation and entrepreneurship training Program(S202210231110S202210231090)
文摘Solar irradiation can efficiently promote the kinetics of the oxygen evolution reaction(OER)during water splitting,where heterojunction catalysts exhibit excellent photoresponsive properties.However,insights into the origins of photoassisted OER catalysis remain unclear,especially the interfaced promotion under convergent solar irradiation(CSI).Herein,novel allotropic Co_(5.47)N/CoN heterojunctions were synthesized,and corresponding OER mechanisms under CSI were comprehensively uncovered from physical and chemical aspects using the in situ Raman technique and electrochemical cyclic voltammetry method.Our results provide a unique mechanism where high-energy UV light promotes the Co^(3+/4+)conversion process in addition to the ordinary photoelectric effect excitation of the Co^(2+)material.Importantly,visible light under CSI can produce a photothermal effect for Co^(2+)excitation and Co^(3+/4+)conversion,which promotes the OER significantly more than the usual photoelectric effect.As a result,Co_(5.47)N/CoN(containing 28%CoN)obtained 317.9%OER enhancement,which provides a pathway for constructing excellent OER catalysts.
基金supported by the National Natural Science Foundation of China(Grant No.42072168)the National Key R&D Program of China(Grant No.2019YFC0605405)the Fundamental Research Funds for the Central Universities(Grant No.2023ZKPYDC07)。
文摘The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been weak.Based on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different strata.The gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary environment.With increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to inorganic.The origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and mantle-derived.The shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic gas.Furthermore,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived gas.The discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas.
基金Supported by Natural Science Foundation of Guangxi Zhuang Autonomous Region(2011GXNSFF018006)Special Fund for Bagui Scholar Project~~
文摘[Objective] This study aimed to analyze the volatile constituents in Lonicera japonica Thunb. from different origins. [Method] HP-5MS capillary columns were used and column temperature was controlled by a program. MS analysis was performed with EI and quadruple mass analyzer. The volatile constituents in L. japonica Thunb. were identified by NIST02 and Wiley275 libraries, and their relative contents were determined with chromatographic peak area normalization method. [Result] According to GC-MS total ion-current chromatograms, 35 volatile constituents were identified in L. japonica Thunb. from Guangxi Zhuang Autonomous Region, mainly including methyl linolenate, n-hexadecanoic acid and ζ-muurolene; 18 volatile constituents were identified in L. japonica Thunb. from Hunan Province, mainly including n-hexadecanoic acid, linoleic acid and α-curcumene. [Conclusion] Main volatile constituents in L. japonica Thunb. from two different origins varied significantly.
基金supported by the National Natural Science Foundation of Chinathe CASthe National Natural Science Foundation of Guangdong Province
文摘Metallic iron nanoparticles(npFe0)are widespread on the Moon,and their accumulation changes the optical spectra of the lunar surface over time.How the surface color changes largely depends on the size of npFe0:smaller npFe0 reddens the reflectance spectra,while larger npFe0 causes darkening.The resultant color variations greatly complicate remote sensing studies,posing long-term puzzles to astronomers.
基金funded by the Major Program of the National Natural Science Foundation of China (31590823 to H.S.),the National Natural Science Foundation of China(31370004 and 31570213 to J.W.Z.,31700165 to T.D.)the National Key R&D Program of China (2017YFC0505200 to H.S.)CAS ‘Light of West China’ Program to T.D.
文摘1.Introduction The Hengduan Mountains region(HDM)in southwest China,one of the earth's 34 biodiversity hotspots,is characterized by its unique geology,dramatic topography,a climate where snow and below freezing temperatures can occur on any day of the year,by its location at elevations averaging between(1400e)2000 and4500(e5300)meters above sea level(m a.s.l.),and by one of
文摘The ongoing pandemic of coronavirus disease 2019 (COVID-19), caused by infection with human coronavirus 2019 (HCoV-19/SARS-CoV-2/2019-nCoV), is a global threat to the human population. Here, we briefly summarize the available data for the zoonotic origins of HCoV-19, with reference to the other two epidemics of highly virulent coronaviruses, SARSCoV and MERS-CoV, which cause severe pneumonia in humans. We propose to intensify future efforts for tracing the origins of HCoV-19, which is a very important scientific question for the control and prevention of the pandemic.
文摘[Objective] To lay the foundation for the classification and breeding of Litchi (Litchi chinensis Sonn.) through RAPD (Random Amplification Polymorphic DNA) analysis of the Litchi cultivars with different origins. [Method] 5 Litchi cultivars from Sichuan, Guangxi, Guangdong, Fujian and Hainan were used as experimental materials to extract genomic DNA by modified CTAB method. Twenty primers with well reproducibility were randomly selected to conduct RAPD amplification to analyze the polymorphism and genetic relationship of the five cultivars. [Result] The polymor- phism of the five Litchi cultivars was 61%, with the similarity coefficient of 0.571 4- 0.803 6. The similarity coefficient of those from Guangdong and Guangxi was the largest of 0.803 6, and from Sichuan and Hainan was the lowest of 0.571 4. The resolution and production of RAPD was significantly improved by appropriately pro- longing the ramp time from annealing to extension to 0.3℃/s. [Conclusion] This study provided theoretical basis for the classification and breeding of Litchi.
基金The National Natural Science Foundation of China under contract No.41576088the National Key Research and Development Program of China under contract No.2016YFC1402202the research foundation of State Key Laboratory of Estuarine and Coastal Research under contract No.2015KYYW04
文摘In the southwestern Yellow Sea there is a low-salinity and turbid coastal water,the Subei Coastal Water(SCW).The origins of freshwater contents and thus the dissolved terrigenous nutrients in the SCW have been debated for decades.In this study,we used a well-validated numerical model to quantify the contributions of multiple rivers,i.e.,the Changjiang River in the south and the multiple Subei local rivers(SLRs) in the north,in forming this yearround low-salinity coastal water.It is found that the freshwater contents in the SCW is dominated by the Changjiang River south of 33.5°N,by the SLRs north of 34.5°N,and by both sources in 33.5°–34.5°N.Overall,the Changjiang River contributes ~70% in the dry season and ~80% in the wet season of the total freshwater contents in the SCW,respectively.Dynamics driving the Changjiang River Plume to flow northward is the tidal residual current,which can even overwhelm the wind effects in winter seasons.The residual currents turn offshore near the Old Yellow River Delta(OYRD) by the collision of the two tidal wave systems,which transport the freshwater from both sources into the interior Yellow Sea.Water age experiments show that it takes 50–150 d for the Changjiang River Plume to reach the SCW in the spring and summer seasons,thus there is a 2-month lag between the maximum freshwater content in SCW and the peak Changjiang River discharge.In the winter and autumn seasons,the low salinity in inner SCW is the remnant Changjiang River diluted water arrived in the previous seasons.
文摘Pediatric origin of cancer stem cell hypothesis holds great promise and potential in adult cancer treatment, however; the road to innovation is full of obstacles as there are plenty of questions left unanswered. First, the key question is to characterize the nature of such stem cells (concept). Second, the quantitative imaging of pediatric stem cells should be implemented(technology). Conceptually, pediatric stem cell origins of adult cancer are based on the notion that plasticity in early life developmental programming evolves local environments to cancer. Technologically, such imaging in children is lacking as all imaging is designed for adult patients. We postulate that the need for quantitative imaging to measure space-time changes of plasticity in early life developmental programming in children may trigger research and development of the imaging technology. Such quantitative imaging of pediatric origin of adulthood cancer will help develop a spatiotemporal monitoring system to determine cancer initiation and progression. Clinical validation of such speculative hypothesis-that cancer originates in a pediatric environment-will help implement a wait-andwatch strategy for cancer treatment.
文摘Sexism in the English Language is the reflector of a social sexism. The thesis is not only to discuss phenomena of sexism in English in terms of morphology, syntax and semantics, but also to focus on the origins and point out the ways of desexism.
基金supported by Tsinghua University Spring Breeze Fund(2020Z99CFY044)Tsinghua University start-up fundTsinghua University Education Foundation fund(042202008)。
文摘The severe acute respiratory syndrome COVID-19 was discovered on December 31,2019 in China.Subsequently,many COVID-19 cases were reported in many other countries.However,some positive COVID-19 samples had been reported earlier than those officially accepted by health authorities in other countries,such as France and Italy.Thus,it is of great importance to determine the place where SARS-CoV-2 was first transmitted to human.To this end,we analyze genomes of SARS-CoV-2 using k-mer natural vector method and compare the similarities of global SARS-CoV-2 genomes by a new natural metric.Because it is commonly accepted that SARS-CoV-2 is originated from bat coronavirus RaTG13,we only need to determine which SARS-CoV-2 genome sequence has the closest distance to bat coronavirus RaTG13 under our natural metric.From our analysis,SARS-CoV-2 most likely has already existed in other countries such as France,India,Netherland,England and United States before the outbreak at Wuhan,China.
基金Supported by Hainan Province Basic and Applied Basic Research Program(Natural Science)High-level Talents(No.2019RC318)Nanfeng Special Phase III:Investigation and Protection of Cultivated Land and Fishery Water Resources(NFZX2021)the Central Public-interest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences(No.1630032022022)。
文摘[Objectives]This study was conducted to clarify the differences of volatile components in fresh fruit of Morinda citrifolia L.from different origins.[Methods]The method of HS-SPME-GC/MS detection was used to determine the volatile chemical components in fresh fruit of M.citrifolia.[Results]52,52 and 45 volatile components were identified from the fresh fruit of M.citrifolia from Xisha,Wanning and Haikou,respectively.Among them,the number and content of the identified esters were relatively high,mainly methyl caprylate,ethyl caprylate,4-pentenyl caproate,3-methylbuten-2-enyl caprylate,methyl caproate,and ethyl caproate.There were also fatty acids,alcohols,phenols,ketones,aldehydes and other substances.There were 33 common ingredients in the fruit from the three origins,mainly including caprylic acid,caproic acid,capric acid,methyl caprylate,ethyl caprylate,4-pentenyl caproate,3-methylbutene-2-enyl caprylate,methyl caproate,ethyl caproate,methyl caprate and hexyl caproate.[Conclusions]The types and contents of volatile components in fresh fruit of M.citrifolia from different origins were significantly different.
基金Project supported by the ITER-National Magnetic Confinement Fusion Program(Grant Nos.2010GB109000,2011GB108009,and 2014GB123000)the National Natural Science Foundation of China(Grant No.11075119)
文摘Solid helium bubbles were directly observed in the helium ion implanted tungsten(W), by different transmission electron microscopy(TEM) techniques at room temperature. The diameters of these solid helium bubbles range from1 nm to 8 nm in diameter with the mean bubble size about 3 nm. The selected area electron diffraction(SAED) and fast Fourier transform(FFT) images revealed that solid helium bubbles possess body-centered cubic(bcc) structure with a lattice constant of 0.447 nm. High-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)images further confirmed the existence of helium bubble in tungsten. The present findings provide an atomic level view of the microstructure evolution of helium in the materials, and revealed the existence of solid helium bubbles in materials.
文摘Various species of Cu.Pb,Zn and Cr in dust of different origins and diameters were studied using Tessler scheme,and the partition law was revealed, The results indicated that superior form of Cu、Pb、 Zn and Cr was bound to organic master,bound to Fe-Mn oxides,bound to Fe-Mn oxides and residual.So their activity order was Zn>Pb>Cu>Cr.The exchangeable metals bound to carbonates and Fe-Mn oxides of four heary metals in small particles were superior to those in large particles,which illustrated that heavy metals in small paticles were more active and harmful.
文摘The developmental origins of health and diseases(DOHaD)is a concept stating that adverse intrauterine environments contribute to the health risks of offspring.Since the theory emerged more than 30 years ago,many epidemiological and animal studies have confirmed that in utero exposure to environmental insults,including hyperglycemia and chemicals,increased the risk of developing noncommunicable diseases(NCDs).These NCDs include metabolic syndrome,type 2 diabetes,and complications such as diabetic cardiomyopathy.Studying the effects of different environmental insults on early embryo development would aid in understanding the underlying mechanisms by which these insults promote NCD development.Embryonic stem cells(ESCs)have also been utilized by researchers to study the DOHaD.ESCs have pluripotent characteristics and can be differentiated into almost every cell lineage;therefore,they are excellent in vitro models for studying early developmental events.More importantly,human ESCs(hESCs)are the best alternative to human embryos for research because of ethical concerns.In this review,we will discuss different maternal conditions associated with DOHaD,focusing on the complications of maternal diabetes.Next,we will review the differentiation protocols developed to generate different cell lineages from hESCs.Additionally,we will review how hESCs are utilized as a model for research into the DOHaD.The effects of environmental insults on hESC differentiation and the possible involvement of epigenetic regulation will be discussed.
文摘The paper proposes that the four-component structure of political order consists of state, imagination, rule, and accountability whose mental origins are the social brain, theory of mind, the rational brain, and the empirical brain, respectively. The rational brain and the empirical brain are from the thinking brain. This paper posits that in the evolution of political order, the main function of political order is to pacify changed social structure derived from technological revolution. Therefore, the four technological revolutions (the Upper Paleolithic, Agricultural-Bronze, Iron, and Industrial Revolutions) produce the four changed social structures (linked bands, tribe, mega empire, and modern nation, respectively) whose internal conflicts are pacified by the four political revolutions (the imaginative, hierarchical, thinking, bottom-up political revolutions, respectively) to form the four politics (the imaginative egalitarianism, decentralized hierarchical tribalism, centralized top-down thinking, and multilateral bottom-up thinking politics, respectively). In the competitive West originated from Greece and Middle East, the rule of law is the rational rule of competition among competitors, and the accountability of election is the empirical accountability of competition among competitors. In the cooperative East originated from India and China, the rule of relation is the rational rule of cooperation among kin-friends, and the accountability of professional qualification is the empirical accountability of cooperation among kin-friends. For political order, the two viable politics are competitive liberal democracy based on liberty and cooperative well-off democracy (well-off socialism) based on wellbeing. The direction of political order is middle democracy between liberal democracy and well-off democracy based on the multilateral bottom-up thinking politics.
文摘With the development of the rhetoric study from the origins in ancient Athens and The Rhetoric of Aristotle to the formation of modern Communication Study at the beginning of the twentieth century,the Rhetoric Study changed in dynamic and its concepts and theories merged and formed the foundations of Communication Study which focused on personal communication and speech rhetoric skills at that time.At the beginning of the twentieth century,although the Neo-Aristotelian rhetorical scholars from classic rhetoric approach created methodologies and enriched the content of Communication Study under the influence of humanistic study and social science study,but the Communication discipline was still in the embarrassing position.During World War I and World War II,most scholars with backgrounds of social science,history and anthropology carried out the studies of propaganda wars and the message disseminating,and explored the military powers and governments’access to the media and developed serial communication modes from the social science perspective,which laid the foundation for Communication discipline in the academic field.The author analyzed the Rhetoric and Social Science origins of Communication study in Boxing Plato’s Shadow:an Introduction to the Study of Human Communication,which is beneficial and helpful to understand the academic origins of Communication study and its cross-disciplined and embarrassing positions.
基金the China National Natural Science Foundation Program(81460749)National 973 Program(2011CB512004).
文摘Uyghur medicine refers to the traditional medicine of the people residing in the oases of the Taklamakan desert in the North-West corner of modern China.Due to historical and geographical reasons,the ancestors of the modern Uyghurs had extensive contact with Greco-Roman civilization even beginning in the 4th century BCE,and continuing with different extent until the 6th century CE.Thus,the knowledge of Greek humoral medicine spread to the Uyghur regions.When Arab-Persian medicine arrived along with Islam in the 10th century,it met both Buddhist medicine and the developed folk medicine.In this paper,we argue that“Greco-Roman”,“Arab-Persian”and“Uyghur”medicines are all of essentially the same system under holistic humoral medicine.We further assert that“Traditional European Medicine”is based on the same tradition,and,while it was discarded in the West,it has been substantially preserved by the Uyghurs.We also consider the implications of making the two millennial tradition of Uyghur medicine the object of modern scientific research in China.
文摘Honey is a product of the elaboration of flower nectar by bees. The general features and elemental composition of honey depend on its botanical origin. In this study, five color parameters (L*: lightness, a*: red color, b*: yellow color, C*ab and hab) and five elements (Na, K, Mg, Ca and Zn) were determined and related with 91 Thai honey samples. The origins of four botanic types of (1) longan flower (Dimocarpus sp.), (2) lynchee flower (Litchi sp.), (3) sunflower (Helianthus sp.) and (4) wild flower (Eupatorium sp.) using principle component analysis (PCA). The results showed that five color parameters and five metal contents related with the Thai botanic origins of the honeys using principle component analysis (PCA). Six major indicators of PC i (variance is 44.33%) from three color parameters are L*(-0.926), a*(0.927) and hue or hab (0.824) and from three metal contents are K(0.833), Ca(0.816) and Mg(0.595). Two minor indicators of PC2 (variance is 21.58%) from color parameters are b*(-0.934) and Chroma or C*ab (-0.834). Two indicators of PC3 (%variance is 12.47%) from contents of Na (-0.722) and Zn (0.704). Thai Lynchee (C) flower honeys classified using both six parameters in PC 1 and two color parameters in PC2. Thai longan flower (G) honeys classified using the contents of Zn and Na in PC3 parameters. Thai sunflower (S) honeys classified using two color parameters in PC2. Thai wild flower (W) honeys classified using the metal contents of K in PC 1 parameter, Zn and Na in PC3 parameters.
文摘English Allusions are the unique and fixed expressions which mostly derive from the Western myths, legends, fables, literature and Western histories. They are crystallization of language and culture and closely related with cultural traditions. English Allusions have profound meaning although their forms are rather concise and terse. In daily communication, we always use allusions consciously or unconsciously. But the Chinese translation of English Allusions is a hard task for translators for their hidden and cultural background meaning is not as simple as their form. Therefore, this paper explores the origins and the corresponding translation of English allusions. It proposes three translation strategies in English allusion translation, aiming to help target readers accept the English allusions more easily and better understand Western culture through the use of English allusions.