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Caryota obtusa of Arecaceae is a fascinating palm tree native to southwestern China, India, Myanmar, Thailand, Laos and Vietnam. It is an economically important and threatened species and appears as a canopy dominant in some karst areas in Yunnan. We aim to clarify the forest structure, species diversity, population status and regeneration dynamics of C. obtusa in the karst forest ecosystem of Yunnan, China. We established 56 vegetation plots dominated by C. obtusa in 10 counties of southern Yunnan. Based on the plot data, we analyzed the community stratification, floristic composition and C. obtusa’s population structure. We used questionnaires to interview local people and recorded the human activity history in C. obtusa-dominated forests. Caryota obtusa palm forests were distributed on limestone mountain slopes and gullies. There were seven forest community types. The stratification of each community included arborous layer, shrub layer and understory. The communities had rich species composition. For all the plots as a whole of each community type, Shannon–Wiener diversity index of either woody or herbaceous species ranged from 2.1 to 3.8. The diameter at breast height (DBH)-class frequency distribution of C. obtusa was a multimodal type. The regeneration was sporadic and dependent on intermediate natural disturbances. In the current population structure, a number of C. obtusa trees with small DBHs consisted mainly of the forest communities with no or a slight degree of human disturbances. Intensive human activities terribly hindered recruitment of C. obtuse, followed by the medium intensity of human activities.

Dipentodon sinicus Dunn. (Dipentodonaceae) is a rare and threatened relict plant species usually found co-dominating with other relict plants in subtropical forest patches in highly fragmented habitats of southwestern China, northern Vietnam and northeastern Myanmar of East Asia. To date, its management and conservation strategies in the light of climate change have not been explored. We evaluated effects of climate change on the distribution of climatically suitable areas of D. sinicus as found prevailing during the last glacial maximum (LGM), the mid-Holocene and the present time, and predicted the distribution of climatically suitable habitats in 2070 throughout East Asia. The results as derived from ecological niche modeling (ENM) show the current distribution to be limited to the prehistoric (the mid-Holocene and LGM) refugia, and to indicate decreasing probability of presence and a reducing range of distribution for 2070. In addition, the suitable areas predicted with high probability (0.5–1) only account for on average 9.8% of the total area of potential habitats (threshold‒1) among the models for the year 2070, thereby indicating that D. sinicus is highly vulnerable. Under all the future scenarios for the year 2070, 69–74.2% of potential habitats in China would be outside protected areas. We assess and propose priorities for protected areas, and provide suggestions for conservation management strategies., This study received financial support from Science and Technology Department of Yunnan University, China (2019YNU002), the Ministry of Science and Technology of China (2015FY210200-15), Ajuts a Grups de Recerca Consolidats” (grants nos. 2014-SGR514-GREB and 2017-SGR1116) from the Generalitat de Catalunya (Spain), Applied Basic Research Foundation of Yunnan Province, China (Grant No. 2019FB058), the Environment Research and Technology Development Fund (JPMEERF15S11407) of the Environmental Restoration and Conservation Agency of Japan, and the Kakenhi Grant Number 15H02833., Highlights Abstract Keywords 1. Introduction 2. Material and methods 2.1. Species 2.2. Occurrence data and ecological niche modeling 3. Results 3.1. Model performance and present potential distribution 3.2. Projected distribution during the mid-Holocene (ca. 6000 yr BP) and LGM (ca. 21,000 yr BP) 3.3. Projected distribution under future climate (2070) 4. Discussion 4.1. Effects of climate change on spatial distribution patterns of D. sinicus 5. Recommendations for future conservation efforts and management Declaration of competing interest Acknowledgements Appendix A. Supplementary data References

Garcinia xanthochymus is a widely used folk medicine in southwestern China. Previous studies indicated it possesses potential anti-diabetic activities both in vitro (Fu et al., 2014; Nguyen et al., 2017) and in vivo (Shivanand et al., 2017). To discover bioactive ingredients from it and unveil their mechanism of action against diabetes, the present study was designed to isolate constituents from extract of G. xanthochymus, determine their structures, screen their activities and investigate mechanism of action of the active substances. Twenty compounds including a new depsidone named garciniadepsidone A (20) and 19 known xanthones were obtained. All of them were screened to discover the active compounds with anti-diabetic activities. Finally, three xanthones including 12b-hydroxy-des-d-garcigerrin (5), 1,2,5,6-tretrahydroxy-4-(1,1-dimethyl-2-propenyl)-7-(3-methyl-2-butenyl) xanthone (13) and 1,5,6-trihydroxy-7,8-di(3-methyl-2-butenyl)-6',6'-dimethylpyrano (2',3':3,4) xanthone (18) were found to be able to significantly stimulate the glucose uptake in the skeleton muscle cells. The effects of the three compounds were comparable to those of insulin and metformin. Based on molecular mechanistic study, it was found that both of compound 5 and 13 promoted glucose uptake by activating phosphatidylinositol-3 kinase (PI3K)/the serine/threonine kinase protein kinase B (PKB/Akt) signaling pathway and AMP-activated protein kinase (AMPK) signaling pathway, resulting in the translocation of GLUT4 in L6 myotubes without affecting the expression of GLUT4. Compound 5 and 13 have great potential to be developed as promising leads to target diabetes.

Glycogen synthase kinase-3β (GSK-3β) was immobilized on magnetic beads (MBs) by affinity method for the first time. The enzyme-immobilized MBs were coupled with high-performance liquid chromatography-ultraviolet (HPLC-UV) technique to establish a cost-effective and reliable method for screening of inhibitors of GSK-3β. A peptide substrate of GSK-3β containing a tyrosine residue was employed since it can be sensitively detected by UV detector at 214nm. The substrate and its phosphorylated product were separated by baseline within 10min. The enzyme activity was determined by the quantification of peak area of the product. Parameters including enzyme immobilization, enzyme reaction and the performance of immobilized-enzyme were investigated. The immobilized enzyme can be reused for 10 times and remain stable for 4 days at 4°C. The inhibitory activities of extracts of 15 traditional Chinese medicines (TCMs) were screened. As a result, three of them including Euonymus fortunei, Amygdalus communis and Garcinia xanthochymus were found possessing high inhibitory activities (inhibition rate >90%). From G. xanthochymus, a new inhibitor of GSK-3β, fukugetin, was discovered with an IC50 value of 3.18±0.07μM. Enzyme kinetics and molecular docking experiments further revealed the inhibitory mechanism, indicating fukugetin was a non-ATP competitive inhibitor interacting with the phosphate recognizing substrate binding site of GSK-3β.

This paper studies the system unbalance caused by rooftop Photovoltaic Generation Systems (PVGSs) in distribution networks and proposes an improved method. The voltage and current unbalance studies for three extreme cases considering all rooftop PVGSs being connected to one single phase and then the stochastic analyses for the integration cases of rooftop PVGSs are considered. These three extreme cases lead to severe system unbalance problems. An improving method that combines the On Load Tap Changer (OLTC) and the optimal phase arrangement of distribution transformers is proposed in this paper to mitigate the system unbalance. The OLTC-based improving method is applied first. If the system unbalance is still out of range, the optimal phase arrangement of distribution transformers is further used to mitigate the system unbalance problem. The objective function of optimal phase arrangement is to minimize the system unbalance with the constraints of voltage limits, line flow limit, etc. Test results show that the proposed method can improve the system unbalance significantly even under very extreme cases.

Direct molecule dynamics (MD) simulations have also been performed to study heterogeneous nucleation and growth of iron on C60 molecule. The grown mechanism of this crystallization process was explored. The results indicate that 92 iron atoms attach to C60 molecule surface can form new covalent bond, forming a closed regular icosahedron. More atoms grow in layer to form bigger regular closed clathrate base on the structure of former one. As increase of atoms number, there will appear some crystal faces.

A second-order effective medium theory (second-order EMT) and thin film theory have been used to design a polarizing beam splitter (PBS) composed of one-dimensional sub-wavelength metal grating, considering the material of metal to be copper (Cu). It was analyzed by the finite difference time domain method for the wavelength of 1500nm. A high extinction ratio in transmission (>55.71dB) over abroad interval of angles of incidence ([-60o, 60o]) is achieved with the depth and the filling factor of the grating chosen to be 350nm and 0.3762, which are selected to transmit TM polarized light and reflect TE polarized light as much as possible at normal incident. The loss of the TE polarized light for the Cu structures is approximately less than 5.55% due to the absorption of Cu in a large angle range. The desired property will enable this type of polarizing beam splitter to be used in diverging beams. When the PBS needs to transmit approximately 25% of the TE polarized light and as much as possible the TM polarized light, it can be used in magneto-optical data storage head. But the depth of grating has been changed (approximately d=40nm) and TM transmission is only 94.7%. But it can be further improved (from 94.7% to 97.97%) by etching into the substrate.

The constituents were isolated and purified by the silica gel and semi-preparative HPLC, and their structures were elucidated by NMR spectral and MS data. Fifteen compounds were isolated from the ethyl acetate fraction of 95% ethanol extract from the leaves of Garcinia xanthochymus, and identified as 5, 7, 4'-trihydroxy-6-(3-hydroxy-3-methylbutyl)-flavone(1), 1,5-dihydroxy-3-methoxyxanthone(2), 1, 3-dimethoxy-5-hydroxy xanthone(3), kaempferol(4),(2S,3S)-trans-dihydrokaempferol(5), 3, 24, 25-trihydroxytirucall-7-ene(6), 4-hydroxycinnamic acid(7), isovanillic acid(8),(Z)-2-(2,4-dihydroxy-2, 6, 6-trimethylcyclohexylidene)acetic acid(9), volkensiflavone(10), morelloflavone(11), 3, 8″-biapigenin(12), bilobetin(13), fukugiside(14), GB2a glucoside(15). Compound 1 is a new compound, compounds 5, 6, 9 and 13 are isolated from the genus Garcinia for the first time, and compounds 4, 7-8, 10-12, 14 and 15 are firstly found from this plant. α-Amylase inhibitory activities of 10 compounds were determined using starch azure as the substrate, and the results show that compound 13 has the inhibitory activities against α-amylase, IC₅₀ values of compound 13 and acarbose are 8.12, 4.32 μmol•L⁻¹ respectively.

Fault Current Indicators (FCIs) with communication interfaces have been widely used in distribution systems to reduce fault-finding time. The effectiveness of a Fault Management System (FMS) composed of FCIs greatly depends on the performance of the communication network deployed by the FCIs and the failure rates of distribution systems. The conventional techniques only focus on the issues of optimal number and location of FCIs or communication network deployment individually, therefore, the effectiveness of an FMS cannot be assessed realistically. A systematic effectiveness assessment methodology for FMS considering the performance of the communication network deployed by the FCIs and the failure rates of distribution systems is vital and is investigated in this paper. A communication evaluation platform is designed in this paper and used to acquire the field measurements of communication parameters. The communication parameters, especially the Packet Success Rate (PSR), between two adjacent FCIs are measured, and the Probability Density Function (PDF) of the PSR can be built accordingly. The effectiveness of the FMS is then assessed by stochastic analysis considering the failure rates of the distribution system and PSR PDFs between two adjacent FCIs. Due to the characteristics of easy installation, maintenance, longer battery life, lower cost, and so on of ZigBee, the ZigBee-based FCI is mainly discussed in this paper. In order to efficiently find the communication route when a fault occurs, a fast communication route tracking method is also proposed in this paper and its feasibility is demonstrated in an actual distribution system. Experimental and simulation results demonstrate the validity of the proposed systematic effectiveness assessment methodology for an FMS composed of FCIs. The proposed assessment methodology can more realistically react to the actual conditions of the FMS and therefore save on installation time and costs.

Spontaneous chromosome doubling via union of unreduced (2n) gametes has been thought to be the way that common wheat (Triticum aestivum L.) was originated from the hybridization of T. turgidum L. with Ae. tauschii Cosson. Previous works have observed unreduced gametes in F1 hybrids of Ae. tauschii with six of the eight T. turgidum subspecies. It is not clear, however, whether the formation of these unreduced gametes is a norm in the F1 hybrids. In the present study, we tried to answer this question by assessing the occurrence frequency of unreduced gametes in 115 T. turgidum–Ae. tauschii hybrid combinations, involving 76 genotypes of seven T. turgdium subspecies and 24 Ae. tauschii accessions. Our data show that these hybrid combinations differed significantly (P ≤ 0.01, F = 11.40) in selfed seedset, an indicator for production of unreduced gametes. This study clearly showed that meiotic restitution genes are widely distributed within T. turgidum. However, significant differences were found between as well as within T. turgidum subspecies and in the interaction of the T. turgidum genotypes with those of Ae. taushii. The possible application of the meiotic restitution genes from T. turgidum in production of double haploids is also discussed.

Aim: To investigate the α 1B -adrenoceptor (α 1B -AR)-mediated cAMP response and underlying mechanisms in HEK293 cells. Methods: Full-length cDNA encoding α 1B -AR was transfected into HEK293 cells using the calcium phosphate precipitation method, and α 1B -AR expression and cAMP accumulation were determined by using the saturation radioligand binding assay and ion-exchange chromatography, respectively. Results: Under agonist stimulation, α 1B -AR mediated cAMP synthesis in HEK293 cells, and blockade by PLC-PKC or tyrosine kinase did not reduce cAMP accumulation induced by NE. Pretreatment with pertussis toxin (PTX) had little effect on basal cAMP accumulation as well as norepinephrine (NE)-stimulated cAMP accumulation. In addition, pretreatment with cholera toxin (CTX) neither mimicked nor blocked the effect induced by NE. The extracellular Ca 2+ chelator egtazic acid (EGTA), nonselective Ca 2+ channel blocker CdCl 2 and calmodulin (CaM) inhibitor W-7 significantly reduced NE-induced cAMP accumulation from 1.59%±0.47% to 1.00%±0.31%, 0.78%±0.23%, and 0.90%±0.40%, respectively. Conclusion: By coupling with a PTX-insensitive G protein, α 1B AR promotes Ca 2+ influx via receptor-dependent Ca 2+ channels, then Ca 2+ is linked to CaM to form a Ca 2+ -CaM complex, which stimulates adenylyl cyclase (AC), thereby increasing the cAMP production in HEK293 cell lines.

α-Amylase inhibitors play an important role in management of diabetes and obesity. In order to rapidly discover potent α-amylase inhibitors from medicinal plants, a ligands-screening method based on enzyme-immobilized magnetic nanoparticles integrated with HPLC was developed. Amine-terminated magnetic nanoparticles were prepared for the immobilization of α-amylase. Based on the affinity theory, the α-amylase-coated magnetic nanoparticles were employed to fish out the ligands from the extracts of Garcinia xanthochymus, and the elutes were examined by HPLC. As a result, three ligands were screened out. Isolation and identification were carried out subsequently. By analyzing the UV, MS and NMR spectra, they were identified as three biflavonoids including GB2a glucoside (2), GB2a (3) and fukugetin (4). The IC50 values of the three compounds were also determined. The results suggest the proposed approach is efficient and accurate, and has great potential in rapid discovery of drug candidates from medical plants.

In the title compound, C15H22O2, the C=C bond lengths in the cyclohexene ring and the allylic acid group [1.325 (3) and 1.324 (3) Å] are almost equal and are shorter than those observed in ethylene. The C=O and C—O bond lengths in the allylic acid group [1.201 (3) and 1.321 (3) Å] are almost equal to those of formic acid. There is an intramolecular hydrogen bond between the allylic acid H atom and the hydroxy O atom [C...O = 2.673 (2) Å and C—H...O = 101°].

Three new 7,8-secolignans, schisandlignans A–C (1, 2, and 4), one new dibenzocyclooctadiene lignan, schisandlignan D (5), together with nine known lignans 3′,4′-dimethoxybenzoic acid (3″,4″-dimethoxyphenyl)-2-methyl-3-oxobutyl ester (3), gomisin J (6), rubrisandrin A(1b) (7), interiotherin B (8), schisantherin D (9), ( − )-machilusin (10), ganschisandrine (11), henricine A (12), and (+)-1-hydroxy pinoresinol (13), were isolated from the rattan of Schisandra sphenanthera. Their structures were determined by analysis of 1D and 2D NMR spectroscopic data.

The global outbreak of influenza A (H1N1) has led to the Ministry of Health of China listing it as one of the A-class infectious diseases. Pneumonia is the most serious complication of influenza A, commonly causing death. Populations are ordinarily susceptible to influenza A. This study aimed to investigate the imaging manifestation features of critical influenza A (H1N1) pneumonia and to improve its diagnostic techniques.A total of seven death cases from critical influenza A (H1N1) pneumonia were retrospectively analyzed on their imaging manifestations and autopsy data. Pulmonary CT scanning was performed for five cases, with one receiving additional chest X-ray and chest CT scanning, and chest postero-anterior position X-ray examination was performed for other two. Autopsy was performed for five cases and postmortem examinations were performed for other two cases.The seven cases of influenza A showed critical manifestations in 4 - 7 days after symptoms onset, with two having basic diseases of diabetes and one being pregnant. Extensive blurry high-density shadows of bilateral lungs were found in three cases, which were most obvious in middle and inferior parts of lungs. Pulmonary CT scanning revealed bilateral flaky parenchymal shadows in peripheral, dorsal and fundus segments of the middle-inferior parts of lungs, with one case of complicated pneumothorax, atelectasis and pleural effusion and another case of thin-walled cavity and dilated bronchi shadows in the superior parts of lungs.Diagnostic imaging is an important assessing tool for critical influenza A (H1N1) pneumonia. The imaging manifestations are characteristic instead of being specific. The definitive diagnosis can be made in combination with clinical examinations and laboratory tests.

To study the chemical constituents of Euphorbia antiquorum L., the constituents were isolated with normal-phase and reverse-phase silica gel column chromatography and their structures were elucidated on the basis of spectroscopic data. Seven terpenoids were obtained from EtOAc extract of E. antiquoru L. They were identified as antiquorine A (1), antiquorine B (2), ent-13S-hydroxy-16-atisene-3,14-dione (3), taraxerol (4), 3beta-hydroxy-25,26,27-trisnorcycloart-24-oic acid (5), 9beta,19-cyclolanostan-3beta-ol (6) and psi-taraxastane-3,20-diol (7) by spectral analysis. Compounds 1-3 are diterpenoids, which belonged to abietane, ent-kaurane and atisane respectively. Among them, compounds 1 and 2 are new compounds. Compounds 4-7 are triterpenoids, and compound 5 is a degraded cycloartane triterpenoid which is a new natural product. Compound 7 was isolated from this plant for the first time. It demonstrated that the chemical structures of constituents in this plant were diverse.

To study the chemical constituents of aerial parts of Laggera pterodonta (DC.) Benth., the air-dried aerial parts of this plant were powered and extracted with boiling water and purified by silica gel column chromatography and recrystallized. Eleven compounds were obtained from L. pterodonta. They were identified as to be 6-O-beta-D-glucopyranosyl-carvotanacetone (1), pterodontic acid (2), 1beta-hydroxy pterondontic acid (3), pterodontoside A (4), pterodondiol (5), pterodontriol B (6), 5-hydroxy-3,4', 6,7-tetramethoxyflavone (7), artemitin (8), chrysosplenetin B (9), quercetin (10) and beta-sitosterol (11). Compound 1 is a new monoterpene glucoside. Compounds 10 and 11 were isolated from this plant for the first time. Compounds 2 and 5 showed moderate activity against bacteria including Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, Mycobacteium phlei and Bacillus circulans by paper disc diffusion method, while they both displayed no activity against Escherichia coli.