Search

A copper‐catalyzed α,β‐regioselective (2+4) cycloaddition of propargylic esters with o‐hydroxyphenyl substituted secondary phosphine oxides (SPOs) was established, which afforded a series of phosphorus‐containing six‐membered heterocycles in high yields. This reaction represents the first α,β‐regioselective (2+n) cycloaddition of propargylic esters via the intermediates of copper‐allenylidenes, which will enrich the chemistry of propargylic esters and copper‐allenylidenes. Moreover, this work also represents the first application of o‐hydroxyphenyl substituted SPOs as 1,4‐dinucleophiles in (2+4) cycloadditions, which provides a useful protocol for the synthesis of phosphorus‐containing six‐membered heterocycles with potential bioactivity. [ABSTRACT FROM AUTHOR]

The controllable synthesis of phosphorus (P) doped noble metal electrocatalysts with a well‐defined structure and composition has attracted sufficient attention in energy chemistry. In this study, atomic‐level P‐doped Pt nanodendrites (PtP NDs) with tunable composition and highly branched architecture are successfully prepared by post‐phosphating reaction of sodium hypophosphite monohydrate at room temperature. Due to its electrophilic properties, P effectively regulates the electronic structure of the d‐orbitals of Pt. The charge change induced by P on a local scale can effectively regulate the selective adsorption of electrocatalytic reaction intermediates. The electrocatalytic results show that the η10 value of PtP NDs in hydrogen evolution reaction is only 13.3 mV, and the mass activity of PtP NDs in methanol oxidation reaction is 4.2 A mg−1, which is 3.8 times larger than that of commercial Pt/C. Most importantly, the atomic‐level P doping greatly improves the stability of PtP NDs, which is crucial to facilitating the catalysts' commercialization process. [ABSTRACT FROM AUTHOR]

For a hepatitis C virus (HCV) mathematical model considering host immune system which is studied by Blé et al. (2018), uniform persistence and global asymptotic stability of the endemic equilibrium of the model are considered, and a set of feasible sufficient conditions are obtained by constructing appropriate Lyapunov functions. Our results largely improved those in related works. [ABSTRACT FROM AUTHOR]

The design and synthesis of metallic nanocatalysts with distinct nanostructures and composition is still a noteworthy topic in the electrochemistry field. In this work, we have realized the morphological evolution of PdIr nanostructures in aqueous solution through the synergistic effect of self‐assembled functional surfactants and different halide ions, and achieved precise control of the kinetic and thermodynamic crystalline growth due to the different reduction potential between PdCl42−, PdBr42−, and PdI42−. The actual precursors of PdCl42− resulted in ultrathin nanodendrites, PdClxBr(4−x)2− for nanosheets and fewer branched nanodendrites, PdClxI(4−x)2− for nanorings, nanoflowers and multiply concave nanocubes. Owing to the synergistic advantages of structure and composition (alloyed Ir), PdIr nanodendrites exhibited enhanced electrocatalytic activity, anti‐poisoning ability, and stability toward alcohols (including ethanol, methanol, and glycerol) electrooxidation reactions. The results would be helpful for thoroughly understanding how structure‐directing surfactants and halide ions synergistically determine the production of advanced metallic nanocrystals. [ABSTRACT FROM AUTHOR]

The mechanical properties of polymer‐based composites are generally determined by the interfacial adhesion between the inorganic component and the polymer itself. In this work, high‐density polyethylene (HDPE) composites were prepared with polydopamine(PDA)‐modified short basalt fibers (D‐BF) as an inorganic filler, in which the interface between HDPE and D‐BF was mediated by maleic anhydride‐grafted polyethylene (PE‐g‐MAH) and maleic anhydride‐grafted poly(ethylene‐co‐octene) elastomer (POE‐g‐MAH). The adding mass ratio of both the compatibilizers had a significant effect on the mechanical properties of the prepared HDPE/D‐BF composites. When total 5 wt% of both PE‐g‐MAH and POE‐g‐MAH with a mass ratio of 1/3 was introduced, the tensile strength and elongation at break of the composite containing 2.5 wt% D‐BF reached 53.7 ± 0.8 MPa and 1174 ± 17%, respectively, about 73% and 157% higher than those of the pristine HDPE. Therefore, this work demonstrated a feasible way to prepare polymeric composites with high strength and high toughness via the dual‐compatibilizer and PDA modification of the fillers. [ABSTRACT FROM AUTHOR]

Objective: To quantitively characterize the morphology of cervical disc herniation (CDH) causing cervical spondylotic radiculopathy (CSR) and investigate whether the morphological features of CDH are associated with clinical outcomes in CSR patients treated by posterior percutaneous full‐endoscopic cervical discectomy (PPECD). Methods: This is a single‐center retrospective study. Eighty‐seven PPECD‐treated patients meeting the inclusion criteria were included between May 2017 and May 2019. Based on preoperative T2‐weighted magnetic resonance imaging (MRI), we designed and measured six morphological parameters of CDH for all patients to reflect its relative position to cervical spinal cord and protruding degree: DC‐SC distance from the center of disc (DC) and the center of spinal cord (SC); DC‐DP distance from the center of cervical disc (DC) to the peak of herniation (DP); internal diameter of the disc; axial length of CDH; central angle of CDH formed by central axes of CDH and spinal cord; the modified index of CDH. We recorded general information, neck disability index (NDI) scores, visual analog scale (VAS) scores of neck and arm of all patients preoperatively and postoperatively at 1‐year follow‐up. The association of preoperative general variables and morphological parameters with clinical outcomes were explored by utilizing logistic regression and receiver operating characteristic curve (ROC) analysis. Results: The preoperative neck‐VAS, arm‐VAS, and NDI were significantly decreased after PPECD and remained at a low value at follow‐up. In regards to the morphological parameters of CDH, the mean value of DC‐SC distance, DC‐DP distance, internal diameter of the disc, axial length of CDH, central angle of CDH, and modified index of CDH were 1.61 ± 0.30 cm, 1.66 ± 0.32cm, 1.04 ± 0.21 cm, 0.63 ± 0.19cm, 39.38° ± 11.94°, and 0.39 ± 0.24, respectively. For patients grouped by difference in the recovery rate of NDI and arm‐VAS (excellent improved group, EI; and limited improved group, LI), there were no differences in the age, gender, surgical segments, and morphological parameters, except for the central angle of CDH. According to binary logistic regression analysis, only the preoperative central angle of CDH was significantly associated with postoperative NDI recovery (odds ratio: 0.873; 95% confidence interval: 0.819–0.931, P = 0.002). ROC analysis showed the optimal cut‐off value of the central angle of CDH for predicting the postoperative improvement of functional outcomes is 33.788°. Conclusion: Preoperative morphology of CDH is related to the outcomes of CSR patients after PPECD. Patients with a large central angle of CDH (>33.788°) have more likelihood of ameliorating neurological symptoms of CSR. There is the potential to select the central angle of CDH as a predictor for outcomes of PPECD in treating CSR. [ABSTRACT FROM AUTHOR]

In this work, a facile aqueous synthesis strategy was used (complete in 5 min at room temperature) to produce large‐size Pd, PdCu, and PdPtCu nanomeshes without additional organic ligands or solvent and the volume restriction of reaction solution. The obtained metallic nanomeshes possess graphene‐like morphology and a large size of dozens of microns. Abundant edges (coordinatively unsaturated sites, steps, and corners), defects (twins), and mesopores are seen in the metallic ultrathin structures. The formation mechanism for porous Pd nanomeshes disclosed that they undergo oriented attachment growth along the ⟨111⟩ direction. Owing to structural and compositional advantages, PdCu porous nanomeshes with certain elemental ratios (e. g. Pd87Cu13) presented enhanced electrocatalytic performance (larger mass activity, better CO tolerance and stability) toward ethanol oxidation. [ABSTRACT FROM AUTHOR]

Periodic arrays of plasmonic nanoantennas can enhance the directionality of light emission of nearby fluorophores and, therefore, have a great potential for a broad range of applications. Unfortunately, their narrow spectral bandwidth and the anisotropy of their optical resonances limit the use of these structures in applications such as solid state lighting. In this article, we study an alternative for periodic structures: Vogel's golden spirals. These spirals are deterministic structures with an approximate circular symmetry and a Fourier transform that is much more broadband than that of periodic lattices. Combining k-space Stokes polarimetry and theoretical calculations, we first investigate the light scattering from Vogel's arrays and the coupling between individual nanoantennas. Next, photoluminescence measurements show that the spirals can enhance the forward emission of incoherent fluorescent sources embedded in a waveguide that also encloses the spiral. The enhancement occurs over a broad spectral band, proving the potential of Vogel's golden spirals for broadband light-emitting devices. [ABSTRACT FROM AUTHOR]

Understanding the cellular composition and trajectory of human tooth development is valuable for dentistry and stem cell engineering research. Previous single‐cell studies have focused on mature human teeth and developing mouse teeth, but the cell landscape of human embryonic dental development is still unknown. In this study, tooth germ tissues were collected from aborted foetus (17–24 weeks) for single‐cell RNA sequence and spatial transcriptome analysis. The cells were classified into seven subclusters of epithelium, and seven clusters of mesenchyme, as well as other cell types such as Schwann cell precursor and pericyte. For epithelium, the stratum intermedium branch and the ameloblast branch diverged from the same set of outer enamel‐inner enamel‐ALCAM+ epithelial cell lineage, but their spatial distribution of two branches was not clearly distinct. This trajectory received spatially adjacent regulation signals from mesenchyme and pericyte, including JAG1 and APP. The differentiation of pulp cell and pre‐odontoblast showed four waves of temporally distinct gene expression, which involved regulation networks of LHX9, DLX5 and SP7, and these genes were regulated by upstream ligands such as the BMP family. This provides a reference landscape for the research on early human tooth development, covering different spatial structures and developmental periods. [ABSTRACT FROM AUTHOR]

Most patients with inflammatory bowel disease (IBD) develop anemia, which is attributed to the dysregulation of iron metabolism. Reciprocally, impaired iron homeostasis also aggravates inflammation. How this iron‐mediated, pathogenic anemia‐inflammation crosstalk is regulated in the gut remains elusive. Herein, it is for the first time revealed that anemic IBD patients exhibit impaired production of short‐chain fatty acids (SCFAs), particularly butyrate. Butyrate supplementation restores iron metabolism in multiple anemia models. Mechanistically, butyrate upregulates ferroportin (FPN) expression in macrophages by reducing the enrichment of histone deacetylase (HDAC) at the Slc40a1 promoter, thereby facilitating iron export. By preventing iron sequestration, butyrate not only mitigates colitis‐induced anemia but also reduces TNF‐α production in macrophages. Consistently, macrophage‐conditional FPN knockout mice exhibit more severe anemia and inflammation. Finally, it is revealed that macrophage iron overload impairs the therapeutic effectiveness of anti‐TNF‐α antibodies in colitis, which can be reversed by butyrate supplementation. Hence, this study uncovers the pivotal role of butyrate in preventing the pathogenic circuit between anemia and inflammation. [ABSTRACT FROM AUTHOR]

We propose a diffusive viral model incorporating cell‐to‐cell infection mode, nonlinear incidences, incubation period, and spatial heterogeneity. For the spatially heterogeneous model, we derive the extinction/persistence result by the basic reproduction number R0. For the spatially homogeneous model, we study global stabilities of steady states by establishing Lyapunov functions. The existing method for studying global stabilities of diffusive viral models has been generalized, which weakens the required conditions. Some existing results can be covered and improved. A specific example is given to illustrate the general results. In addition, we show that R0 is underestimated if we neglect incubation period of infected cells. [ABSTRACT FROM AUTHOR]

Compatibilizing agents, namely, maleic anhydride‐grafted polyolefin elastomer (POE‐g‐MAH) and maleic anhydride‐grafted polypropylene (PP‐g‐MAH), were simultaneously employed in isotactic polypropylene (PP)/titanate whisker composites for high impact toughness and improved mechanical properties. POE‐g‐MAH was used in the composites for reinforcing impact strength of PP. In the meanwhile, PP‐g‐MAH compatibilized counterpart was enrolled for modulating the composite properties. With 3‐aminopropyl triethoxysilane modified whiskers, compatible compatibilizing agent PP‐g‐MAH contributed to maintain the tensile property, while POE‐g‐MAH compatibilized content was prone to improve the composites of PP/whisker with notch impact strength of 9.9 ± 0.7 kJ/m2, which was ~220% higher than that of PP. Validity of interface regulation revealed that POE‐g‐MAH and PP‐g‐MAH were dominated separately to improve impact and tensile strengths with the diversely compatibilized part ratio, and strived in combination for more superior mechanical properties. β‐Form crystals detected by differential scanning calorimetry in the composites favored the extra improvement of tenacity, and crystalline morphology confirmed the promoted heterogeneous nucleation of PP composites with addition of PP‐g‐MAH. Variations of glass transition temperature and loss factor also indicated the different effects of the two compatibilizers on the interface between whiskers and PP matrix. POLYM. COMPOS., 40:3421–3428, 2019. © 2019 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The article discusses a study that focuses on the impact of mineral resource development structure (DS) on development efficiency in order to adjust factors of structural elements to help mining enterprises. Topics discussed include factors of mining enterprise DS such as technical personnel, ore mining capacity utilization and degree of automation; transformation and upgradation of mining enterprises and influence of proportion of technical personnel on mine recovery and governance rate.

The crystallization chemistry of silica‐based zeolites in ionic liquids remains highly puzzling and interesting in the field of zeolite science. Herein, we report the successful ionothermal synthesis of germanosilicate zeolites. The ionothermal templating effect with respect to the structure, alkalinity and concentration of organic additives was comparatively studied. The results showed that a small amount of organic base could effectively aid the dissolution of silica source and facilitate the crystallization of germanosilicate zeolites with ionic liquid as template. Remarkably, STW and IRR structures constructed with double‐four‐ring (D4R) structure‐building units were ionothermally prepared using 1‐ethyl/butyl‐3‐methyl imidazolium and 1‐benzyl‐3‐methyl imidazolium ionic liquids as template, respectively. Ionothermal synthesis tailored with organic base showed suitable chemistry for the formation of germanium‐containing siliceous D4R units. This finding will be helpful for the rational exploration of novel extra‐large‐pore zeolitic structures. IRResistible: Germanosilicate zeolites were ionothermally prepared in the presence of organic base, which aided the dissolution of silica source and facilitated the crystallization of STW and IRR structures with ionic liquids of different structure as template. Ionothermal chemistry was effectively tailored by using an organic base, which exhibits a remarkable capability for the formation of germanium‐containing siliceous D4R units. [ABSTRACT FROM AUTHOR]

Abstract: The ionothermal synthesis of extra‐large‐pore aluminophosphate zeotype with −CLO topological structure, DNL‐1, was studied by using 1,6‐hexanediamine and several quaternary ammonium compounds with different types of cations and anions as co‐structure‐directing agents (co‐SDAs). The phase selectivity and crystallization process were investigated, and results showed that the crystallization of the −CLO and LTA structures correlated with the alkalinity and concentration, rather than with the structure of the co‐SDA. By combining solid/solution 13C NMR spectroscopy and other characterizations on DNL‐1 obtained with different co‐SDAs, it was demonstrated that the ionic‐liquid cation was unalterably occluded in the structure, whereas occlusion of the co‐SDA cation was not imperative. A plausible crystallization pathway was accordingly deduced, in which alkaline co‐SDA, which acted as an acidity regulator in the ionothermal system, could facilitate the formation of the double‐four‐ring (d4r) unit (Al4P4O20), and influence their subsequent assembly mode around ionic‐liquid cations, and thus, direct the crystallization of −CLO and LTA structures at different concentrations of co‐SDA. [ABSTRACT FROM AUTHOR]

Diet analysis of potential small mammals pest species is important for understanding feeding ecology and evaluating their impact on crops and stored foods. Chinese mole shrew (Anourosorex squamipes), distributed in Southwest China, has previously been reported as a farmland pest. Effective population management of this species requires a better understanding of its diet, which can be difficult to determine with high taxonomic resolution using conventional microhistological methods. In this study, we used two DNA metabarcoding assays to identify 38 animal species and 65 plant genera from shrew stomach contents, which suggest that A. squamipes is an omnivorous generalist. Earthworms are the most prevalent (>90%) and abundant (>80%) food items in the diverse diet of A. squamipes. Species of the Fabaceae (frequency of occurrence [FO]: 88%; such as peanuts) and Poaceae (FO: 71%; such as rice) families were the most common plant foods identified in the diet of A. squamipes. Additionally, we found a seasonal decrease in the diversity and abundance of invertebrate foods from spring and summer to winter. Chinese mole shrew has a diverse and flexible diet throughout the year to adapt to seasonal variations in food availability, contributing to its survival even when food resources are limited. This study provides a higher resolution identification of the diet of A. squamipes than has been previously described and is valuable for understanding shrew feeding ecology as well as evaluating possible species impacts on crops. [ABSTRACT FROM AUTHOR]

Preserving the structural and stratigraphic discontinuities or edges is essential in seismic data processing and interpretation. According to several numerical experiments, it is obvious that random noise has a constant spectral density, whereas the structural features vary significantly within different frequency bands, which means that the ratio between the densities of noise and structural features varies significantly in different frequency bands. Therefore, we propose a method called adaptive hybrid diffusion to attenuate random noise, which utilizes a novel adaptive frequency‐based parameter. First, the adaptive hybrid diffusion method decomposes the seismic sections into several band‐limited portions using variational mode decomposition. These portions are called intrinsic mode functions, in which noise and structural energy have distinct differences. Subsequently, utilizing the adaptive frequency‐based parameter, each intrinsic mode function is divided into several monotonous portions that represent the noise or structural area. Afterwards, the total variation and L2 minimization algorithms are utilized separately to suppress the noise in different band‐limited monotonous areas. The algorithms are chosen dynamically, as the portion changes with the change in the adaptive parameter. Finally, these denoised portions are combined to obtain the denoised seismic section. Experimental results on synthetic and field seismic data showed that seismic noise is effectively suppressed by the adaptive hybrid diffusion method, with the edge details of seismic events well preserved. [ABSTRACT FROM AUTHOR]

Considering the high rate of osteoclast‐related diseases worldwide, research targeting osteoclast formation/function is crucial. In vitro, we demonstrated that chitooligosaccharide (CS) dramatically inhibited osteoclastogenesis as well as osteoclast function dose‐dependently. CS suppressed osteoclast‐specific genes expression during osteoclastogenesis. Furthermore, we found that CS attenuated receptor activator of nuclear factor kappa B ligand (RANKL)‐mediated mitogen‐activated protein kinase (MAPK) pathway involving p38, erk1/2, and jnk, leading to the reduced expression of c‐fos and nuclear factor of activated T cells c1 (NFATc1) during osteoclast differentiation. In vivo, we found CS protected rats from periodontitis‐induced alveolar bone loss by micro‐computerized tomography and histological analysis. Overall, CS inhibited RANKL‐induced osteoclastogenesis and ligature‐induced rat periodontitis model, probably by suppressing the MAPK/c‐fos/NFATc1 signaling pathway. Therefore, CS may be a safe and promising treatment for osteoclast‐related diseases. [ABSTRACT FROM AUTHOR]

Question: Understanding the mechanisms determining species composition is one of the central goals in ecology. The limestone landscape of southwestern China is one of the most widely known landscapes developed on carbonate bedrock in the world. We explored the following question: What are the patterns of species composition and phylogenetic structures of the communities developed on the acid and limestone soils? Location: Southwestern China. Methods: Using 536 plots on acid and limestone soils, we identified distinct vegetation types on both soil types based on hierarchical clustering and ordination. Variation partitioning partitioned the effects of climate, geographic distance and soil on species composition. Generalized linear models determined the effects of climate and soil on phylogenetic diversities. Results: The typical vegetation on acid soils is evergreen broad‐leaved forests characterized by Castanopsis species, while typical vegetation on limestone soils is mixed evergreen and deciduous forests characterized by a high proportion of deciduous trees and calciphytes. Soil type was much more important in driving species composition than climate and spatial distance. The standardized mean pairwise phylogenetic distance (ses.MPD) and mean nearest taxon distance (ses.MNTD) were significantly lower on limestone soils than on acid soils, indicating a more clustered phylogenetic structure. The effect of soil on ses.MPD was stronger than on ses.MNTD, and ses.MNTD increased with increasing annual temperature and precipitation seasonality on acid soils but decreased on limestone soils, suggesting that soil affected phylogenetic structure at relatively deep branches, while climate combined with soil mainly affects the relatively recent branches, as ses.MPD measures phylogenetic structure at deep branches and ses.MNTD that at shallow branches. Conclusions: This study highlights the importance of soil in shaping community structure at a regional scale, and it also reveals the unique features of limestone vegetation and supports the validity of limestone vegetation types in the Chinese vegetation classification system. [ABSTRACT FROM AUTHOR]

Fencing is an effective and practical method for restoring degraded grasslands in northern China. However, little is known about the role of excess litter accumulation due to long‐term fencing in regulating abiotic environment and driving changes in community structure and function. We conducted a three‐year field experiment in two fenced grasslands in Inner Mongolia, and monitored light quantity, soil temperature, and soil moisture continuously, and determined community height, community aboveground net primary productivity (ANPP), and the relative dominance of different plant functional groups. Litter accumulation reduced light quantity and soil temperature but increased soil moisture. The regulating effects of litter accumulation on soil temperature and soil moisture fluctuated temporally and gradually weakened over the growing season. Litter accumulation also altered community vertical structure and function by increasing community height and ANPP. The increase in soil moisture increased the relative dominance of rhizome grasses but suppressed bunch grasses, thereby shifting bunch grass grasslands to rhizome grass grasslands. Our findings provide a potential mechanism for community succession in the context of litter accumulation in fenced grasslands and indicate that the vegetation and ecosystem services of degraded grasslands are improved after appropriate fencing. [ABSTRACT FROM AUTHOR]

Esophageal cancer is one of the most common tumor in the world, and the morbidity rate is as high as 100/100 000 in some parts of China. Therefore, it is important and urgent to explore the pathogenesis of esophageal cancer and find new therapeutic targets for esophageal cancer. In this study, we found that a novel tumor suppressor SPINK5 is significantly reduced in the development of esophageal cancer, and is closely related to the pathological differentiation and lymph node metastasis of esophageal cancer via bioinformatics analysis and esophageal cancer tissue array. Further studies have found that SPINK5 is closely related to Wnt/β‐catenin signaling pathway by bioinformatics analysis and western blot. In esophageal cancer cells, SPINK5 overexpression can inhibit Wnt/β‐catenin signaling pathway. Combined with LiCl or MG‐132 treatment, SPINK5 can inhibit GSK3β phosphorylation and promote β‐catenin protein degradation, thus inhibit Wnt/β‐catenin signaling pathway. In vivo study, SPINK5 overexpression can significantly inhibit the growth of esophageal cancer cells. Our study shows that SPINK5 can inhibit the proliferation, migration, and invasion of esophageal cancer cells by inhibiting Wnt/β‐catenin signaling pathway, and thus plays an important role in the development of esophageal cancer, and may serve as a treatment target of esophageal cancer. [ABSTRACT FROM AUTHOR]

Delta‐like 2 (Dlk2), a glycoprotein highly homologous to Dlk1, belongs to the Notch/Delta/Serrata family. Dlk2 has been shown to be an important regulator of adipogenesis; however, its role in other cellular differentiation processes is still unknown. Therefore, in this study, we aimed to determine the role of Dlk2 in chondrogenic differentiation. We found that Dlk2 overexpression promoted the growth of ATDC5 cells but inhibited insulin‐induced ATDC5 chondrogenic differentiation, as supported by the reduction in cartilage matrix formation and gene expression of aggrecan (acan), collagentype II (col2a1) and X (col10a1). In contrast, Dlk2 silencing inhibited the proliferation of ATDC5 cells but enhanced their chondrogenic differentiation. We then evaluated the roles of mitogen‐activated protein kinases (MAPKs), which are activated by insulin during the chondrogenesis of ATDC5 cells. Overexpression of Dlk2 protein strongly promoted the activation of p38, but not extracellular signal‐regulated kinase (ERK) 1/2 and c‐Jun N‐terminal kinase (JNK). Moreover, as expected, Dlk2 silencing inhibited the activation of p38, but had no effect on the ERK1/2 and JNK pathways. Finally, we also detected the expression of Dlk2 in mouse epiphyseal cartilage during embryo development. The expression of the Dlk2 protein in the limb bud could be detected at embryonic day 11.5; additionally, it was found to decrease in the superficial zones, but remained unchanged in the deep/hypertrophic zones. In conclusion, our results suggested that Dlk2 acted as an important regulator of chondrogenesis through the p38 pathway. These findings may lead to strategies for the treatment of cartilage‐related diseases such as osteoarthritis. [ABSTRACT FROM AUTHOR]

Montane cloud forest is one of the most endangered ecosystems. However, there are few comprehensive studies on the distribution of subtropical montane cloud forest (SMCF). Chamaecyparis forest is one type of SMCF in Taiwan, distributed across the whole island. This study describes eleven types of this forest in Taiwan based on the Braun-Blanquet approach. Plots were selected from the National Vegetation Database of Taiwan. Two alliances were defined, both of which belong to the order Fagetalia hayatae. Topography and altitude explain the contrasting habitat requirements of these two alliances, whereas seasonality of moisture, soil properties and altitude explain differences in floristic composition at the association level. The alliance of Chamaecyparidion formosanae on slopes and ridges includes coniferous or mixed coniferous and evergreen broad-leaved forests; it is found at higher altitudes and is more influenced by the summer monsoon than the other alliance. Five associations are defined within this alliance. The alliance of Pasanio kawakamii - Machilion japonicae growing on slopes and in valleys contains evergreen broad-leaved forests or forests with a mixture of coniferous and evergreen broad-leaved species. Six associations can be determined under the alliance of Pasanio kawakamii- Machilion japonicae. Classification of each syntaxon was formalized using Cocktail Determination Key. [ABSTRACT FROM AUTHOR]

Rab7 plays an important role in regulating endocytic traffic. In view of an emerging role of membrane traffic in signaling and diseases, we have examined the possible role of Rab7 in oncogenesis. The role of Rab7 was investigated using shRNA-mediated knockdown in A431 and MCF7 cancer cells. To our surprise, Rab7 knockdown effectively suppressed anchorage-independent growth of cancer cells in soft agar. Anoikis (matrix-detachment triggered apoptosis) was enhanced, while the level of phosphorylated (active) Akt (which is a key survival factor) was significantly reduced. Also intriguing was the observation that EGFR and Her2 levels were significantly reduced when Rab7 was knocked-down. More robust reduction of EGFR and Her2 levels was observed when knocked-down cells were treated with HSP90 inhibitor geldanamycin (GA). Low concentration of GA (50-100 nm)-induced apoptosis of the Rab7 knocked-down cells but not control cells, suggesting that Rab7 and HSP90 together contribute to the optimal stability of EGFR and Her2 as well as to protect cancer cells from apoptosis. Rab7 seems to protect EGFR and Her2 from proteosome-mediated degradation. These results suggest that Rab7 is likely involved in protecting EGFR and Her2 from being degraded by the proteosome and in maintaining optimal Akt survival signal (especially during cell detachment or when HSP90 is inhibited). Rab7 is potentially a novel target for combinatory therapy with Hsp90 inhibitors. J. Cell. Physiol. 227: 2788-2797, 2012. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Liaotung oak (strictly named as Quercus wutaishanica Mayr, but usually called Q. liaotungensis Koidz) is the main dominant tree species in deciduous broad-leaved forests and mixed coniferous and broad-leaved forests occupying the warm-temperate zone and temperate zone of China. It plays important roles in soil and water conservation. We collected occurrence data of Liaotung oak together with environmental variables, and used 24 environmental layers as indicators of climate, human disturbance and soil characteristics (at a spatial resolution of 5 arc-min) across China. The genetic algorithm for rule-set prediction (GARP) was used to predict the potential distribution area of Liaotung oak. Forward selection, Monte Carlo permutation tests and variation partitioning methods were used to identify the key environmental factors that determined the distribution pattern of Liaotung oak. The results show that (1) GARP predicts the potential distribution area of Liaotung oak with high accuracy, with areas under the receiver operating characteristic curve (AUC) and Kappa index values being relatively high (0.96 ± 0.01, 0.91 ± 0.01); (2) the highest probability of Liaotung oak occurrence is located mainly in Gansu, Shaanxi, Shanxi, Henan, Shandong, Hebei, Liaoning, Jilin, and Heilongjiang provinces in China; (3) climate and disturbance intensity are predominant in determining the geographical boundary of Liaotung oak, with human footprint and precipitation of the coldest quarter being the most important (both explaining 71% variation) among the factors investigated across continental China. While climate and soil factors play important roles in determining the suitability index of Liaotung oak, soil organic carbon and temperature are the critical factors (both explaining 55% variation) among the factors investigated across the potential distribution area. [ABSTRACT FROM AUTHOR]

SET is a multi-functional protein in proliferating cells. Some of the proposed functions of SET suggest an important nuclear role. However, the nuclear import pathway of SET is also unknown and the function of SET in neurons is unclear. Presently, using cortical neurons, we report that the nuclear import of SET is mediated by an impα/impβ-dependent pathway. Nuclear localization signal, 168KRSSQTQNKASRKR181, in SET interacts with impα3, which recruits impβ to form a ternary complex, resulting in efficient transportation of SET into nucleus. By in vitro nuclear import assay based on digitonin-permeabilized neurons, we further demonstrated that the nuclear import of SET relies on Ran GTPase. We provide evidence that this nuclear localization of SET is important in neuronal survival. Under basal conditions, SET is predominately nuclear. However, upon death induced by genotoxic stress, endogenous SET decreases in the nucleus and increases in the cytoplasm. Consistent with a toxic role of SET in the cytoplasm, targeted expression of SET to the cytoplasm exacerbates death compared to wild type SET expression which is protective following DNA damage. Taken together, our results indicate that SET is imported into the nucleus through its association with impα3/impβ, and that localization of SET is important in regulation of neuronal death. [ABSTRACT FROM AUTHOR]