We investigate 21st-century hydroclimate changes over the United States (US) during winter and the sources of projection uncertainty under three emission scenarios (SSP2–4.5, SSP3–7.0, and SSP5–8.5) using CMIP6 models. Our study reveals a robust intensification of winter precipitation across the US, except in the Southern Great Plains, where changes are very small. By the end of the 21st century, winter precipitation is projected to increase by about 2–5% K−1 over most of the US. The frequency of very wet winters is also expected to increase, with 6–7 out of 30 winters exceeding the very wet threshold under the different scenarios. Our results suggest that the enhancement of future winter precipitation is modulated largely by coupled dynamic and thermodynamic responses, though partly offset by thermodynamic responses. Overall, our results highlight a high likelihood of increasing impacts from winter precipitation due to climate change.

AbstractThe occurrence of extreme hot and dry summer conditions in the Pacific Northwest region of North America (PNW) has been known to be influenced by climate modes of variability such as the El Niño-Southern Oscillation and other variations in tropospheric circulation such as stationary waves and blocking. However, the extent to which the subseasonal remote tropical driver influences summer heat extremes and fire weather conditions across the PNW remains elusive. Our investigation reveals that the occurrence of heat extremes and associated fire-conducive weather conditions in the PNW is significantly heightened during the boreal summer intraseasonal oscillation (BSISO) phases 6-7, by ~50–120% relative to the seasonal probability. The promotion of these heat extremes is primarily attributed to the enhanced diabatic heating over the tropical central-to-eastern North Pacific, which generates a wave train traveling downstream toward North America, resulting in a prominent high-pressure system over the PNW. The ridge, subsequently, promotes surface warming over the region primarily through increased surface radiative heating and enhanced adiabatic warming. The results suggest a potential pathway to improving subseasonal-to-seasonal predictions of heatwaves and wildfire risks in the PNW by improving the representation of BSISO heating over the tropical-to-eastern North Pacific.

Abstract Reliable regional temperature projections including heat extremes are essential for climate change adaptation and mitigation. Taking China as an example, simple averages from Coupled Model Intercomparison Project Phase 6 (CMIP6) models project high warming due to sampling many high climate sensitivities in the ensemble. Here, we develop an emergent constraint (EC) framework to obtain constrained mean and daily maximum temperature (TXx) warming over China by using observed global warming and local residual warming. The constrained annual mean and TXx warming over China (2.33°C [1.61–3.05°C] and 2.31°C [1.21–2.99°C]) are 0.65°C [0.04–1.76°C] and 0.63°C [–0.50–2.39°C], respectively, lower than raw projections (2.98°C [1.85–4.22°C] and 2.94°C [2.04–4.39°C]) for 2080–2099 under the intermediate‐emission scenario. Approximately half model uncertainty is reduced after constraint. The land area (population) experiencing temperature extremes in our metric is 78% (85%) of the raw projections. Our results imply a lower impact of extreme heat than implied by current raw CMIP6 projections.

High Mountain Asia (HMA) has experienced a spatial imbalance in water resources in recent decades, partly because of a dipolar pattern of precipitation changes known as South Drying–North Wetting 1 . These changes can be influenced by both human activities and internal climate variability 2 , 3 . Although climate projections indicate a future widespread wetting trend over HMA 1 , 4 , the timing and mechanism of the transition from a dipolar to a monopolar pattern remain unknown. Here we demonstrate that the observed dipolar precipitation change in HMA during summer is primarily driven by westerly- and monsoon-associated precipitation patterns. The weakening of the Asian westerly jet, caused by the uneven emission of anthropogenic aerosols, favoured a dipolar precipitation trend from 1951 to 2020. Moreover, the phase transition of the Interdecadal Pacific Oscillation induces an out-of-phase precipitation change between the core region of the South Asian monsoon and southeastern HMA. Under medium- or high-emission scenarios, corresponding to a global warming of 0.6–1.1 °C compared with the present, the dipolar pattern is projected to shift to a monopolar wetting trend in the 2040s. This shift in precipitation patterns is mainly attributed to the intensified jet stream resulting from reduced emissions of anthropogenic aerosols. These findings underscore the importance of considering the impact of aerosol emission reduction in future social planning by policymakers.

为了解毛山小橘(Glycosmis craibii)的化学成分,采用硅胶柱层析、ODS柱层析、Sephadex LH-20凝胶柱层析和高效液相色谱等现代色谱分离技术,从毛山小橘枝叶95％乙醇提取物中分离得到9个生物碱类化合物.根据化合物的理化性质和波谱数据,其结构分别鉴定为de-N-methyl-O-noracronycine(1)、去甲山油柑碱(2)、glycocitrineⅡ(3)、acrifoline(4)、3-hydroxy-2,4-dimethoxy-10-methyl-9-acridanone(5)、阿塔宁(6)、glycosolone(7)、3-(3?,3?-dimethylallyl)-4,8-dimethoxy-N-methyl-quinolin-2-one(8)和4-methoxy-N-methyl-2-quinolone(9).所有化合物均为首次从该植物中分离,其中化合物2、3、5、6和9为首次从山小橘属植物中分离得到.

A phytochemical investigation on the stems of Melicope ptelefolia led to the isolation of four new cinnamic acid derivatives, meliptefoliaric A-D (1-4), together with one known related analogue (5). The chemical structures of new cinnamic acid derivatives (1-4) were ambiguously established on the basis of comprehensive spectroscopic methods. All these isolated compounds 1-5 were tested in vitro for their neuroprotective effects against 6-hydroxydopamine induced cell death in human neuroblastoma SH-SY5Y cells. Cinnamic acid derivatives 1-5 displayed remarkable neuroprotective activities possessing EC50 values ranging from 0.10 +/- 0.02-10.71 +/- 0.28 mu M.

Ethnopharmacological relevance: The morphological characteristics of Ganoderma cochlear (Blume & T. Nees) Bres were identical to G. sinsense J.D. Zhao, L.W. Hsu & X.Q. Zhang, however, with the fungus stipe lying in the back of the pileus. Fruiting bodies and spores of G. cochear have been traditionally used for smoothing, sleeping improvement, memory impairment, anti-aging, and prolonging life. Alzheimer's disease (AD) is a chromic progressive neurodegenerative disorder associated with loss of memory and cognition. Hallmarks of AD include aging, amyloid-beta plaques, neurofibrillary tangles, neuron loss, neuronal degeneration, network disruption, cognitive dysfunction, inflammation and oxidation stress. In this study, norlanostanoids from G. cochear are identified as potential neurotrophic chemists related to the memory impairment usage to slow down pathogenetic process and restore neural circuits for AD. Aim of study: Chemical and biological investigations in this study uncovered the potential constituents related to the traditional usage of G. cochlear. Materials and methods: The extract of the mushrooms was purified using various column chromatography techniques and high-performance liquid chromatography (HPLC). The structures of the isolates were elucidated by combination of spectral, and single crystal X-ray diffraction analysis. The neurotrophic activity was evaluated by the differentiation state of PC12 cells, and the dose-dependent and time-dependant expression of growth-ssociated protein (GAP-43) was analyzed by western blotting. Results: Ganorbifates J-T (1-11), eleven previously undescribed triterpenoids together with five known trinorlanostanoids (12-16) were isolated from the fruiting bodies of G. Cochlear. Among them, ganorbifates N-O (5-6) had a demethylation at C-28 compared to the classic skeleton of 3,4-seco-25,26,27-trinorlanostanoids to form a new group of 3,4-seco-25,26,27,28-tetranorlanostanoids. Based on this, a novel skeleton of ganorbifate M (4) was further established by the arrangement of C-29 from C-4 to C-7. A plausible biosynthetic pathway of compounds 4-6 was proposed. Eight of the sixteen isolates showed neurotrophic activity with the concentration of 10 mu M. Furthermore, compound 15 exhibited a dose-dependent neurogenic activity, and also strengthened the expression of the growth-associated protein (GAP-43) in NGF-induced PC-12 cells, whereas 11 showed an inhibitory effect at higher concentration. Conclusion: These results demonstrated that 3,4-seco-norlanostanoids had reliable potential in promoting the outgrowth of PC-12 cells and could be used in the prevention and treatment of Alzheimer's disease, which is consist with the beneficial effects of G. Cochlear.

A phytochemical study of the stems of Homalium stenophyllum Merr. & Chun led to the isolation of two new phenolic glycosides (1 and 2) and three known compounds (3–5). The molecular structures of these isolated new phenolic glycosides (1 and 2) were unambiguously established on the basis of comprehensive spectroscopic methods. All the isolated new compounds were evaluated for their cytotoxicities against three human cancer cell lines: HeLa, A-549, and MCF-7 in vitro.

依据IPCC第六次评估报告（AR6）第一工作组报告第四章的内容，对未来全球气候的预估结果进行解读。报告对21世纪全球表面气温、降水、大尺度环流和变率模态、冰冻圈和海洋圈的可能变化进行了系统评估，并对2100年以后的气候变化做了合理估计。评估指出全球平均表面气温将在未来20年内达到或超过1.5℃，平均降水也将增加，但随季节和区域而异，同时变率将增大。大尺度环流和变率模态受内部变率影响较大。到21世纪末，北冰洋可能出现无冰期；全球海洋会继续酸化，平均海平面将持续上升，百年内上升幅度依赖不同排放情景，都在2100年后继续升高。在最新的评估中采用多种约束方法，减小了预估不确定性的范围。AR6对于低排放情景以及“小概率高增暖情节”的关注为应对气候变化提供了更多、更完整的信息。综合报告的评估结果指出，未来需要进一步减小区域，特别是季风区气候预估的不确定性，并从科学研究和模式发展两方面加强我国气候预估能力的建设。

地球气候系统模式是开展多学科、多圈层集成研究的重要平台,其发展是国际地学领域特别是全球变化领域竞争的前沿.中国的地球气候系统模式研发工作始于20世纪80年代,最近10年得到快速发展.研发格局上已经形成中国科学院、有关部委和高校三足鼎立的局面.文中在简要回顾中国地球气候系统模式早期发展历史的基础上,总结了中国参加第6次耦合模式比较计划的9个地球气候系统模式的技术特点,初步评估了中国4个模式对全球和东亚气候模拟的基本性能,分析了其在4种共享社会经济路径情景下对全球降水与温度的预估变化及其与平衡态气候敏感度的联系.最后,结合国际态势,从发展的角度提出未来中国气候模式研发工作需要加强的8个方向.

Abstract Changes in hydrological cycle under 1.5°C and 2.0°C warming are of great concern on the post‐Paris Agreement agenda. In particular, the annual range of precipitation, that is, the difference between the wet and dry seasons, is important to society and ecosystem. This study examines the changes in precipitation annual range using the Community Earth System Model low‐warming (CESM‐LW) experiment, designed to assess climate change at stabilized 1.5°C and 2.0°C warming levels. To reflect the exact annual range in different regions, wet and dry seasons are defined for each grid point and year. Based on this metric, the precipitation annual range would increase by 3.90% (5.27%) under 1.5°C (2.0°C) warming. The additional 0.5°C of warming would increase annual range of precipitation by 1.37%. The enhancement is seen globally, except in some regions around the subtropics. Under the additional 0.5°C of warming, a significant increase in the annual range occurs over 15% (22%) of the ocean (land) regions. The increase is associated with the enhanced precipitation during wet season. Moisture budget analysis shows that the enhancement in annual range is dominated by vertical moisture advection, which includes thermodynamic (TH, moisture) and climate dynamic (CD, circulation changes) terms. The TH term plays a dominant role, while the CD term partly offsets the effects of the TH term. The TH term dominates over most regions except for part of the tropical ocean and some of the land regions, where the CD term is also remarkable. Thus, the enhancement of the annual range of precipitation is mainly caused by the increase in moisture.

Abstract Background The reconstruction of phylogenetic relationships for allopolyploids using genomic data is challenging because hybridization and polyploidy can blur history. In cyprinids, one allopolyploidization event involves goldfish and common carp, yet little is known about the origins of other cyprinid polyploid lineages, including their maternal and paternal ancestral lineages. Results Herein we employ 10 HOX genes, genomic and transcriptomic data of representative species from seven subfamilies in Cyprinidae to investigate the origins of polyploid lineages. Analyses of the nuclear and mitochondria genomes reveal that the Schizothoracinae and Cyprininae share the same maternal common ancestor, and identify the candidate genes for identifying maternal gene-copies from Cyprininae. Gene-trees show a close relationship between Sinocyclocheilus grahami and Cyprininae, and indicate that they share the same whole genome duplication (WGD) event about 12.10 ~ 14.03 Ma. Another allopolyploidization event involves Torinae; one duplication clustering with Schizothoracinae and Schizopygopsinae identifies them as paternal siblings. Further, Labeoninae has a history of recurrent hybridization, which is supported by both gene-trees from genomes and HOX genes. Conclusions Collectively, the diverse WGD history makes Cyprinidae a candidate system for investigating the origin of hybridization and polyploidization in vertebrates. Further investigations should enlarge the representatives, combine morphological traits, and reconstruct gene-trees based on whole-genome markers.

In October 2015,a new species of the family Cobitidae,Bibarba wenliuensis sp.nov.,was dis-covered from underground water in Qiubei County,Yunnan Province,China.It can be distinguished from its two congeners by the following combination of characteristics:body with no pigments and no scales,head smaller,eyes degenerated completely,dorsal fin with 6 branched rays,dorsal fin origin posterior to vertical of pelvic-fin origin,caudal-peduncle length 2 5 .0 % of SL,shorter rostral barbels, longer maxillo-mandibular barbels,caudal peduncle with long and distinct dorsal and ventral crests.

In this study, COI and 16S rRNA genes were used to molecularly identify dried seahorse and pipefish sold on the Chinese market. One hundred and ninety-eight products, including 168 seahorse and 30 pipefish, were collected from dried seafood sellers in Zhanjiang (Guangdong province, China) and analyzed. Overall, the study identified 5 different species: Hippocampus trimaculatus, H. spinosissimus and H. kelloggi in seahorse products and Solegnathus hardwickii and S. spinosissimus in pipefish products. All the aforesaid species were randomly sold under the generic umbrella term of Hai ma (seahorse) and of Hai long (pipefish) irrespectively of the price. The present study supports the main pathways of seahorse and pipefish exploitation already described in the literature and confirms previous concerns about the impact that illegal and not regulated trade could have on syngnathids. In particular, the huge economic value of dried products seems to represent the strongest incentive to fishing despite the presence of a legislative framework aimed at managing the wild population of seahorse and pipefish. A proper description on the label, comprising at least the scientific denomination and a "recognizable" Chinese commercial name, is needed to avoid deception of consumers and bypassing of official controls.

Fish maws have been commonly recommended and consumed as delicacies, medicine and tonics in Asia over many centuries. However, the true species of the fish maws in the trade is unknown. It is difficult to identify the fish species just based on their morphological characters of swim bladders. In this study, 96 fish maw products commercialized in the market were analyzed in order to authenticate species. Direct sequencing method based on fragments of the 165 rRNA gene and COI gene were carried out and results showed that the fish maw were extracted from porcupinefish. 53 products were Diodon liturosus, 40 products were Diodon hystrix and three products were Chilomycterus reticulates. Therefore, this work facilitates the identification of fish maw products in the market, support of food control and protection of consumers' rights. Moreover, based on the previous toxicity reports, it is suggested that the Spot-fin porcupinefish D. hystrix maw exists potential food security threat to the consumers. (C) 2017 Elsevier Ltd. All rights reserved.

Amblyceps yunnanensis, a new species, is described here based on the specimens collected from a tributary of the upper Irrawaddy in the western Yunnan Province, China. It differs from all its congeners by the following combination of morphological features: skin smooth with a complete lateral line; adipose-fin originates at vertical level from anterior one quarter of the length of the anal-fin base, in the form of a low and smooth edge; dorsal-fin with one very weak spine; pectoral-fins without spines; caudal-fin truncated without pinnate-like rays.

The phylogenetic relationships of Asian schilbid catfishes of the genera Clupisoma, Ailia, Horabagrus, Laides and Pseudeutropius are poorly understood, especially those of Clupisoma. Herein, we reconstruct the phylogeny of 38 species of catfishes belonging to 28 genera and 14 families using the concatenated mitochondrial genes COI, cytb, and 16S rRNA, as well as the nuclear genes RAG1 and RAG2. The resulting phylogenetic trees consistently place Clupisoma as the sister taxon of Laides, and the five representative Asian schilbid genera form two monophyletic groups with the relationships (Ailia (Laides, Clupisoma)) and (Horabagrus, Pseudeutropius). The so-called "Big Asia" lineage relates distantly to African schilbids. Independent analyses of the mitochondrial and nuclear DNA data yield differing trees for the two Asian schilbid groups. Analyses of the mitochondrial gene data support a sister-group relationship for (Ailia (Laides, Clupisoma)) and the Sisoroidea and a sister-taxon association of (Horabagrus, Pseudeutropius) and the Bagridae. In contrast, analyses of the combined nuclear data indicate (Ailia (Laides, Clupisoma)) to be the sister group to (Horabagrus, Pseudeutropius). Our results indicate that the Horabagridae, recognized by some authors as consisting of Horabagrus, Pseudeutropius and Clupisoma does not include the latter genus. We formally erect a new family, Ailiidae fam. nov. for a monophyletic Asian group comprised of the genera Ailia, Laides and Clupisoma.