Competitive interactions drive critical ecological processes in plant communities. Yet, how competitive interactions are influenced by polyploidy that has a widespread incidence in plants remains ...largely unknown.
To evaluate the hypothesis of competitive asymmetry between polyploids and diploids, we competed tetraploid and diploid plants of perennial herbaceous Chrysanthemum indicum L. (Asteraceae) at different relative frequencies under contrasting soil water contents. We quantified the interaction intensity between competing plants of the same (intraploidy) and different ploidy levels (interploidy), and measured functional traits related to gas exchange and plant water use to understand the underlying mechanisms.
The stronger competitive effect of tetraploids on diploids than that of diploids on tetraploids provided evidence for the competitive asymmetry. As a stronger competitor, tetraploids were limited more by individuals of their own than by diploids. Such competitive asymmetry was not only maintained under reduced soil water content, but also translated into higher above‐ground biomass of tetraploids. Tetraploids showed more resource‐acquisitive traits than diploids under high soil water content and more resource‐conservative traits under reduced soil water content. As such, the higher trait plasticity in tetraploids than diploids likely explained the competitive asymmetry.
Synthesis. These results elucidate the nature and magnitude of species interactions between polyploid and diploid plants under changing environments and the underlying mechanisms, and provide important insights into the prevalence and persistence of polyploid plants under a changing climate.
These results elucidate the nature and magnitude of species interactions between polyploid and diploid plants under changing environments and the underlying mechanisms, and provide important insights into the prevalence and persistence of polyploid plants under a changing climate.
Interactions at plate boundaries induce stresses that constitute critical controls on the structural evolution of intraplate regions. However, the traditional tectonic model for the East Asian margin ...during the Mesozoic, invoking successive episodes of paleo-Pacific oceanic subduction, does not provide an adequate context for important Late Cretaceous dynamics across East Asia, including: continental-scale orogenic processes, significant sinistral strike-slip faulting, and several others. The integration of numerous documented field relations requires a new tectonic model, as proposed here. The Okhotomorsk continental block, currently residing below the Okhotsk Sea in Northeast Asia, was located in the interior of the Izanagi Plate before the Late Cretaceous. It moved northwestward with the Izanagi Plate and collided with the South China Block at about 100Ma. The indentation of the Okhotomorsk Block within East Asia resulted in the formation of a sinistral strike-slip fault system in South China, formation of a dextral strike-slip fault system in North China, and regional northwest–southeast shortening and orogenic uplift in East Asia. Northeast-striking mountain belts over 500km wide extended from Southeast China to Southwest Japan and South Korea. The peak metamorphism at about 89Ma of the Sanbagawa high-pressure metamorphic belt in Southwest Japan was probably related to the continental subduction of the Okhotomorsk Block beneath the East Asian margin. Subsequently, the north-northwestward change of motion direction of the Izanagi Plate led to the northward movement of the Okhotomorsk Block along the East Asian margin, forming a significant sinistral continental transform boundary similar to the San Andreas fault system in California. Sanbagawa metamorphic rocks in Southwest Japan were rapidly exhumed through the several-kilometer wide ductile shear zone at the lower crust and upper mantle level. Accretionary complexes successively accumulated along the East Asian margin during the Jurassic–Early Cretaceous were subdivided into narrow and subparallel belts by the upper crustal strike-slip fault system. The departure of the Okhotomorsk Block from the northeast-striking Asian margin resulted in the occurrence of an extensional setting and formation of a wide magmatic belt to the west of the margin. In the Campanian, the block collided with the Siberian margin, in Northeast Asia. At about 77Ma, a new oceanic subduction occurred to the south of the Okhotomorsk Block, ending its long-distance northward motion. Based on the new tectonic model, the abundant Late Archean to Early Proterozoic detrital zircons in the Cretaceous sandstones in Kamchatka, Southwest Japan, and Taiwan are interpreted to have been sourced from the Okhotomorsk Block basement which possibly formed during the Late Archean and Early Proterozoic. The new model suggests a rapidly northward-moving Okhotomorsk Block at an average speed of 22.5cm/yr during 89–77Ma. It is hypothesized that the Okhotomorsk–East Asia collision during 100–89Ma slowed down the northwestward motion of the Izanagi Plate, while slab pull forces produced from the subducting Izanagi Plate beneath the Siberian margin redirected the plate from northwestward to north-northwestward motion at about 90–89Ma.
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•Applications of biomass using TG, FTIR, and their combination are summarized.•Thermal degradation of lignocellulosic and no-lignocellulosic biomass is addressed.•The evolved gases ...including CO2, CO, H2, CH4 during the conversion are summarized.•TG-FTIR is a promising analytical technique for co-pyrolysis and co-gasification.
Effective methods of biomass characterization are needed for energy production due to the increase in biomass to bioenergy conversion capacity and the availability of various biomass sources. The utilization of biomass has been enhanced through thermochemical conversion techniques such as torrefaction, pyrolysis, and gasification. The biomass analytical techniques have been developed to decrease the time and energy required for biomass conversion performance. Thermogravimetric analyzer (TG) and Fourier transform infrared spectroscopic (FTIR) analytical techniques facing several limitations when applied individually. Thus, TG coupled with FTIR (TG-FTIR) was used to analyze the main parameters of biomass and improved the energy crop growing developments. In addition, TG-FTIR can determine the suitable ratio for two different biomass or coal blending during the co-pyrolysis and co-gasification to achieve the optimum synergetic interaction. In this review, thermochemical conversion processes such as torrefaction, pyrolysis, and gasification are presented. The analysis of the thermochemical conversion of biomass with the use of TG and FTIR individually are then discussed. Lastly, this review aims to discuss the applications of TG-FTIR techniques that have been applied to the analysis of evolved gas from the thermochemical processing of biomass to biofuels.
Coronavirus disease 2019 (COVID-19), caused by infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is transmitted through respiratory droplets and close contact 1–4. To ...diagnose COVID-19, oropharyngeal swab (OP swab) sampling is widely used for viral nucleic acid detection 3. However, healthcare workers who perform OP swab are at high risk of infection due to aerosol from patients during the process of sampling. And the quality of manual OP swabs is inconsistent among different collectors, which may lead to misdiagnosis 5. Use of a remote-controlled OP swab robot has the potential to avoid close contact between healthcare workers with patients, and thus reduce the risk of SARS-CoV-2 infection during sampling. Here, we invented a robotic sampling (RS) system and evaluated the safety and efficacy of this system on OP swab sampling during the period of pandemic.
Clinical application of the safety and effectiveness of an intelligent oropharyngeal-swab robot, and its implication for the COVID-19 pandemic
https://bit.ly/2BUsV55
The nomenclature of
Cephalotaxus lanceolata
is controversial. After a thorough literature investigation, the nomenclatural problems have been resolved. This name was published in W. C. Cheng et al. ...(1975) and, although ascribed to “K. M. Feng”, there is no suggestion that the descriptive material in the protologue was provided by K. M. Feng. Under Art. 46.5 of the ICN, this name should be attributed to K. M. Feng ex W. C. Cheng et al. but not to K. M. Feng alone. It has been claimed that the name is an illegitimate later homonym of one published by Beissner in 1901, but Beissner never accepted this name in any of his publications and so, under Art. 36.1, he did not validly publish an earlier homonym.
Cephalotaxus lanceolatus
was first validly published in W. C. Cheng et al. (1975).
Due to their high specific capacities beyond 250 mA h g
−1
, lithium-rich oxides have been considered as promising cathodes for the next generation power batteries, bridging the capacity gap between ...traditional layered-oxide based lithium-ion batteries and future lithium metal batteries such as lithium sulfur and lithium air batteries. However, the practical application of Li-rich oxides has been hindered by formidable challenges. To address these challenges, the understanding of their electrochemical behaviors becomes critical and is expected to offer effective guidance for both materials and cell development. This review aims to provide fundamental insights into the reaction mechanisms, electrochemical challenges and modification strategies of lithium-rich oxides. We first summarize the research history, the pristine structures, and the classification of lithium-rich oxides. Then we review the critical reaction mechanisms that are closely related to their electrochemical features and performances, such as lattice oxygen oxidation, oxygen vacancy formation, transition-metal migration, layered to spinel transitions, 'two-phase mechanism', and lattice evolution. These discussions are coupled with state-of-the-art characterization techniques. As a comparison, the anionic redox reactions of layered sodium transition metal oxides are also discussed. Finally, after a brief overview of the correlation among the aforementioned mechanisms, we provide perspectives on the rational design of lithium-rich oxides with high energy densities and long-term cycling stability.
This review summarizes the history and critical working mechanisms of Li-rich oxides with a special focus on anionic redox reactions.
Despite the advancement of medical science, diseases are part‐and‐parcel of human life. Plants have provided humans with medicines since time immemorial, and are still one of the primary sources for ...drug discovery. Brassica rapa L., commonly known as turnip, is one of the world's oldest cultivated vegetables. Besides being an important vegetable and source of oil, turnip is also used as a traditional medicine for the treatment of headaches, chest complaints, rheumatisms, oedemas, gonorrhoea, syphilis, and rabies. Glucosinolates and isothiocyanates (mainly 2‐phenylethyl, 4‐pentenyl, and 3‐butenyl derivatives) are the main constituents of turnip with diverse bioactivities, especially for the protective effect against cancers. Besides, flavonoids, phenolics, indoles and volatiles are also concomitant in this plant. Pharmacological investigation on turnip revealed the antitumor, antihypertensive, antidiabetic, antioxidant, antiinflammatory, hepatoprotective, and nephroprotective effects. The anticancer property was found to be the most promising biological activity of turnip with 2‐phenylethyl isothiocyanate, phenylpropionitrile, brassicaphenanthrene A, 6‐paradol, and trans‐6‐shogaol as the major active constituents. Flavonoids and phenolics with high free radical scavenging activity should be corresponding to the antioxidant effects. Arvelexin, an indole derivative in turnip, was reported with various effects involving antiinflamatory, antihypertensive and hypolipidemic potency. In spite of many studies concerning either the chemical constituents or the biological activities of turnip, only a few cases disclosed the active ingredients responsible for diverse bioactivities. This review summarizes the research progress on the chemistry and health‐benefits of turnip over the past 20 years to provide a reference for the further investigation.
•A novel swine enteric alphacoronavirus (tentatively named SeACoV) was isolated from diarrheic piglets in southern China.•SeACoV is likely antigenetically distinct from PEDV, TGEV and PDCoV.•Genomic ...and phylogenetic analysis showed that SeACoV might have originated from the bat coronavirus HKU2.•The extreme amino-terminal domain of SeACoV spike glycoprotein had an extremely high variability compared to that of HKU2.•Experimental infection study showed that SeACoV is infectious and pathogenic in newborn piglets.
Outbreaks of diarrhea in newborn piglets without detection of transmissible gastroenteritis virus (TGEV), porcine epidemic diarrhea virus (PEDV) and porcine deltacoronavirus (PDCoV), have been recorded in a pig farm in southern China since February 2017. Isolation and propagation of the pathogen in cell culture resulted in discovery of a novel swine enteric alphacoronavirus (tentatively named SeACoV) related to the bat coronavirus HKU2 identified in the same region a decade ago. Specific fluorescence signal was detected in Vero cells infected with SeACoV by using a positive sow serum collected in the same farm, but not by using TGEV-, PEDV- or PDCoV-specific antibody. Electron microscopy observation demonstrated that the virus particle with surface projections was 100–120nm in diameter. Complete genomic sequencing and analyses of SeACoV indicated that the extreme amino-terminal domain of the SeACoV spike (S) glycoprotein structurally similar to the domain 0 of the alphacoronavirus NL63, whereas the rest part of S structurally resembles domains B to D of the betacoronavirus. The SeACoV-S domain 0 associated with enteric tropism had an extremely high variability, harboring 75-amino-acid (aa) substitutions and a 2-aa insertion, compared to that of HKU2, which is likely responsible for the extended host range or cross-species transmission. The isolated virus was infectious in pigs when inoculated orally into 3-day-old newborn piglets, leading to clinical signs of diarrhea and fecal virus shedding. These results confirmed that it is a novel swine enteric coronavirus representing the fifth porcine coronavirus.
Because of the importance of novel macrocycles in supramolecular science, interest in the preparation of these substances has grown considerably. However, the discovery of a new class of macrocycles ...presents challenges because of the need for routes to further functionalization of these molecules and good host–guest complexation. Furthermore, useful macrocylic hosts must be easily synthesized in large quantities. With these issues in mind, the recently discovered pillararenes attracted our attention. These macrocycles contain hydroquinone units linked by methylene bridges at para positions. Although the composition of pillararenes is similar to that of calixarenes, they have different structural characteristics. One conformationally stable member of this family is pillar5arene, which consists of five hydroquinone units. The symmetrical pillar architecture and electron-donating cavities of these macrocycles are particularly intriguing and afford them with some special and interesting physical, chemical, and host–guest properties. Due to these features and their easy accessibility, pillararenes, especially pillar5arenes, have been actively studied and rapidly developed within the last 4 years. In this Account, we provide a comprehensive overview of pillararene chemistry, summarizing our results along with related studies from other researchers. We describe strategies for the synthesis, isomerization, and functionalization of pillararenes. We also discuss their macrocyclic cavity sizes, their host–guest properties, and their self-assembly into supramolecular polymers. The hydroxyl groups of the pillararenes can be modified at all positions or selectively on one or two positions. Through a variety of functionalizations, researchers have developed many pillararene derivatives that exhibit very interesting host–guest properties both in organic solvents and in aqueous media. Guest molecules include electron acceptors such as viologen derivatives and (bis)imidazolium cations and alkyl chain derivatives such as n-hexane, alkanediamines, n-octyltrimethyl ammonium, and neutral bis(imidazole) derivatives. These host–guest studies have led to the fabrication of (pseudo)rotaxanes or poly(pseudo)rotaxanes, supramolecular dimers or polymers, artificial transmembrane proton channels, fluorescent sensors, and other functional materials.
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