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Flower development and plant architecture determine the efficiency of mechanized harvest and seed yield in Brassica napus. Although TERMINAL FLOWER 1 (AtTFL1) is a regulator of flower development in Arabidopsis thaliana, the function and regulatory mechanism of TFL1 orthologs in B. napus remains unclear. Six BnTFL1 paralogs in the genome of the B. napus inbred line ‘K407’ showed steadily increasing expression during vernalization. CRISPR/Cas-induced mutagenesis of up to four BnTFL1 paralogs resulted in early flowering and alteration of plant architecture, whereas seed yield was not altered in BnTFL1 single, double, or triple mutants. Six BnTFL1 paralogs, but not BnaA02.TFL1, showed an additive and conserved effect on regulating flowering time, total and terminal flower number, and plant architecture. BnaA10.TFL1 regulates flower development by interacting with BnaA08.FD through the protein BnaA05.GF14nu, resulting in the transcriptional repression of floral integrator and floral meristem identity genes. These findings about the regulatory network controlling flower development and plant architecture present a promising route to modifying these traits in B. napus. [ABSTRACT FROM AUTHOR]

In this paper, we considered a dual-rotor system with crack in shaft. The influence of circular crack in hollow shaft on dynamical response was studied. The equations of motion of 12 elements dual-rotor system model were derived. Harmonic balance method was employed to solve the equations. The critical speed and sub-critical speed responses were investigated. It was found that the circular crack in hollow shaft had greater influence on the first-backward critical speed than the first-forward critical speed. Owing to the influence of crack, the vibration peaks occurred at the 1/2, 1/3 and 1/4 critical speeds of the rotor system, along with a reduction in sub-critical speeds and critical speeds. The deeper crack away from the bearing affected the rotor more significantly. The whirling orbits, the time-domain responses and the spectra were obtained to show the super-harmonic resonance phenomenon in hollow-shaft cracked rotor system. [ABSTRACT FROM AUTHOR]

In this paper, we bring forward a completely perturbed nuclear norm minimization method to tackle a formulation of completely perturbed low-rank matrices recovery. In view of the matrix version of the restricted isometry property (RIP) and the Frobeniusrobust rank null space property (FRNSP), this paper extends the investigation to a completely perturbed model taking into consideration not only noise but also perturbation, derives sufficient conditions guaranteeing that low-rank matrices can be robustly and stably reconstructed under the completely perturbed scenario, as well as finally presents an upper bound estimation of recovery error. The upper bound estimation can be described by two terms, one concerning the total noise, and another regarding the best r-approximation error. Specially, we not only improve the condition corresponding with RIP, but also ameliorate the upper bound estimation in case the results reduce to the general case. Furthermore, in the case of E = 0, the obtained conditions are optimal. [ABSTRACT FROM AUTHOR]

The saturated hydraulic conductivity of soils is a critical concept employed in basic calculation in the geotechnical engineering field. The Kozeny-Carman equation, as a well-known relationship between hydraulic conductivity and the properties of soils, is considered to apply to sands but not to clays. To solve this problem, a new formula was established based on Hagen-Poiseuille's law. To explain the influence on the seepage channel surface caused by the interaction of soil particles and partially viscous fluid, the surface area ratio was introduced. A modified framework for determining the hydraulic radius was also proposed. Next, the relationship between the effective void ratio and the total void ratio was established for deriving the correlation of hydraulic conductivity and total void ratio. The improved equation was validated using abundant experimental results from clays, silts, and sands. According to the results, the accuracies of the proposed model with two fitted multipliers for clays, silts, and sands are 94.6, 96.6, and 100%, respectively, but with only one fitted parameter, the accuracies are 97.1, 91.5, and 100%, respectively. The proposed model can be considered to have a satisfactory capability to predict hydraulic conductivity for a wide variety of soils, ranging from clays to sands. [ABSTRACT FROM AUTHOR]

Purpose: To study the protective effect of interleukin-34 (IL-34) against sepsis in mice, and the mechanism involved. Methods: Ninety healthy male mice were selected and assigned to sham, model and recombinant IL-34 protein groups. The activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were assayed. Moreover, histopathological changes in lung, liver and kidney were recorded, and levels of C-X-C Motif Chemokine Ligand 1 (CXCL1) and C-C Motif Chemokine Ligand 2 (CCL2) in each group of mice were measured. Results: Peritoneal lavage fluid and serum concentrations of AST, ALT, LDH, CXCL1 and CCL2 were significantly elevated, relative to sham mice (p < 0.05). Mice survival in the drug group was markedly increased from day 1 to day 5; also, serum ALT, LDH and AST were significantly reduced, while CXCL1 and CCL2 concentrations in serum and peritoneal lavage fluid were increased, relative to model mice (p < 0.05). Conclusion: IL-34 improves survival of septic mice by inducing CXCL1/CCL2 immune response, resulting in a protective effect on the airway. Thus, the CXCL1/CCL2 pathway mediated by IL-34 may be useful in the development of drugs for the treatment of sepsis. [ABSTRACT FROM AUTHOR]

Due to the oil price fluctuations in recent decades, international and national oil companies have developed programs of strategically oriented development and assets optimization. Many companies have also promptly promoted opportunities for oilfield joint ventures. Therefore, a fast and accurate assessment methodology of oilfield assets, including planning and costs assessment, is expected to be proposed. Oilfield development cost assessment can be dynamically affected by a number of factors, including oilfield internal indexes and macroeconomic indexes. Based on a machine learning algorithm and combining mathematical and statistical methodology, the Microsoft Azure machine learning studio has been used for modeling the oilfield development cost. The proposed method has adopted three algorithms: a neural network, a boosted decision tree, and a decision forest. Results showed that the boosted decision tree and decision forest algorithms can achieve PFI ranking with stable training results. The results of the machine training model have been analyzed, and they showed that the permutation feature importance (PFI) model can provide reasonable scientific and technical support for oil companies and help to attain more effective and accurate estimation and prediction of oilfield assets. [ABSTRACT FROM AUTHOR]

We report a theoretical study of nanobubble stabilization on a substrate by contact line pinning. In particular, we predict the magnitude of the pinning force required to stabilize a nanobubble and the threshold values of the pinning force that the substrate can provide. We show that the substrate chemistry and the local structures of substrate heterogeneity together determine whether or not surface nanobubbles are stable. We find that for stable nanobubbles, the contact angles are independent of substrate chemistry as its effects are cancelled out by the pinning effect. This prediction is in agreement with available experimental data. [ABSTRACT FROM AUTHOR]

• The flow characteristics in the two-stage series cyclone separator were simulated. • The separation performance was interpreted by analyzing particle distribution. • The two-stage cyclone separator was optimized using response surface methodology. Cyclones are generally operated in series when the efficiency of a single cyclone is not sufficient for the process. This study firstly used computational particle fluid dynamics (CPFD) to simulate the gas-solid two-phase flow characteristics in a two-stage series cyclone separator. The separation efficiency and distribution of energy consumption was interpreted by analyzing particle distribution characteristics. Secondly, the structure of the two-stage cyclone separator was optimized via response surface methodology (RSM) to make up for the disadvantage that the distribution of the separation load was non-uniform. The results showed that the grade efficiency for 3 μm of the first-stage cyclone separator was increased from 45.408% to 59.932% compared to the original model. The pressure drop of the first-stage cyclone separator is about 2.147 kPa while the second-stage cyclone separator is about 2.774 kPa. It can be seen that the overall optimized two-stage cyclone separator has the advantages of high efficiency, low energy consumption and load-balanced separation performance. [ABSTRACT FROM AUTHOR]

Ultrasonic microbubbles in combination with microRNA (miRNA s/miRs) exhibited promising effects on cancer treatments. The aim was to investigate the role of miR-378 in hepatoma cells and the efficiency of it in combination with ultrasonic irradiation and SonoVue® microbubbles method for cell transfection. HuH-7, Hep3B and SK-Hep1 cells were transfected with an miR-378 mimic using only Lipofectamine® 3000 or combined with SonoVue microbubbles and ultrasonic irradiation at 0.5 W/cm2 for 30 sec. mRNAs and protein levels of Cyclin D1, Bcl-2, Bax, Akt, p53 and Survivin were detected by reverse transcription-quantitative PCR and western blotting, respectively. Cell survival rate, proliferation, cell cycle and apoptosis were determined by Cell Counting Kit-8, cell double cytochemical staining and flow cytometry, respectively. It was found that using a combination of ultrasonic irradiation and the SonoVue microbubbles method increased the effectiveness of miR- 378 transfection into hepatocellular carcinoma (HCC) cells, and increased the inhibition of cell survival and proliferation. Moreover, miR- 378 increased the rate of apoptosis and upregulated the expression of Bax and p53, and suppressed the cell cycle and downregulated the expression of Cyclin D1, Bcl-2, Akt, ß-catenin and Survivin much more effectively in the HCC cell line by applying the combined method. Thus, miR-378 was shown to be a suppressive factor to reduce proliferation and increase apoptosis in HCC cells. Additionally, the combination of ultrasonic irradiation and SonoVue microbubbles method was more efficient in the transfection of miRNA. [ABSTRACT FROM AUTHOR]

This paper discusses the maturity of source rocks of the Senegal basin through basin simulation, so as to get a better understanding of oil-source correlation. Based on the analysis of pyrolysis chromatography and total organic carbon (TOC) data of core samples taken from 11 wells, the model of Cenomanian-Turonian marine sediment- organic facies was established, and the genetic mechanism of high-quality source rocks was clarified. The results show that source rocks in the Senegal Basin may occur in the Aptian-Albian of Lower Cretaceous and Cenomanian-Turonian of Upper Cretaceous. One is hybrid organic facies in the shallow carbonate platforms in the shelf area and is characterized by moderate to high TOC (<3%) and hidrogen index - HI, (100-400 mg HC/g). The other is well-preserved marine facies in continental slope to abyssal sea, with high TOC (>3%) and high HI (max 900 mg HC/g TOC). Molecular fossils originating from aryl carotene are the indicator of the existence of euphotic zone in the ancient ocean. The compounds of aryl isoprenes and sulfurous aryl isoprenes are detected in the black shale samples of well DSDP 367. They rooted in photosynthetic green sulfur bacteria and the carbon isotope value of these compounds is higher 10~15 than those of fossil molecules of algae and cyanobacteria. Two packages of oil-prone source rocks separately occurr in the Aptian- Albian of Lower Cretaceous and Cenomanian-Turonian of Upper Cretaceous. High-graded marine source rocks of the Senegal Basin may occur in a sulfurous, anoxic deep-water environment with sufficient carbon sequestration. [ABSTRACT FROM AUTHOR]

Particle deposition in flue gas turbines of FCC (Fluid Catalytic Cracking) is very common. Particle deposition causes a lot of damage to turbines, such as corrosion, erosion, increased flow resistance, unbalanced vibrations, and fatigue damage of the blades. In this study, cold and hot experimental systems were built, and the blade was improved by coating it with a chromium carbide alloy at a high temperature to achieve a lower surface roughness of 0.069 μm. The effect of surface roughness on particle deposition was studied both in cold and hot experimental systems. The experimental results indicated that the new improved blade can effectively reduce the particle deposition. With a particle concentration of 100 g/m3, the improved blade reduced the particle deposition by 39.3%, 62.9%, and 53% corresponding to gas temperatures of 700, 500 and 300 °C, respectively. However, the surface roughness has little effect on the distribution of deposited particles. Particle deposition is very common in flue gas turbines. The cold and hot experimental system was built to imitate flue gas turbine. The cold experimental results indicated that the new improved blade can effectively reduce the particle deposition. The hot experimental results also show that the improved blade reduces the particle deposition. Unlabelled Image • The cold and hot experimental system was built to imitate flue gas turbine. • The effect of blade roughness on the quantity and size of particle deposited was studied. • Reduced surface roughness is helpful to reduce particle deposition. • Particle less than 5 μm is easer adhered to the blade. [ABSTRACT FROM AUTHOR]

This study addresses the issue of block-sparse recovery in compressive sensing in the presence of non-Gaussian measurement noise. By using the generalised ℓp-norm noise constraint for 2 ≤ p < ∞ to replace the popular ℓ2-norm, in this study, the authors put forward a truncated ℓ1 model for recovering block-sparse signal. A theoretical analysis is first presented to guarantee the validity of proposed method. If the measurement matrix satisfies an extended block restricted isometry property, the reconstruction error is bounded in the optimisation. Moreover, in order to solve the induced optimisation problem effectively, they present an alternating direction method of multipliers via embedding Karush-Kuhn-Tucker system of ℓp-norm functions into the frame structure of augmented Lagrangian methods. When compared with some of the state-of-the-art methods, the proposed method becomes more competitive. [ABSTRACT FROM AUTHOR]

Objectives: The transmembrane prostate androgen-induced protein (TMEPAI) is aberrantly expressed in many cancer and plays a crucial role in tumourigenesis, which makes it a potential cancer therapeutic target for drug discovery. Materials and methods: Here, we employed a firefly luciferase reporter driven by the TMEPAI gene promoter to screen for compound capable of inhibiting the expression of TMEPAI, and the effects of TMEPAI inhibitor on cancer cell proliferation were evaluated using the colony formation assay, cell cycle analysis, Ki-67 immunofluorescence assay and EdU incorporation assay. Results: 2-(2-nitrobenzylidene) indolin-3-one (JHY-A007-50) was identified and shown to effectively inhibit the TMEPAI promoter activity. Further studies revealed that JHY-A007-50 specifically inhibited the expression of TMEPAI at both the mRNA and protein levels. Moreover, we found that JHY-A007-50 could inhibit cell proliferation and induce cell cycle arrest at the G1 phase. Our results showed that overexpression of TMEPAI decreased the inhibitory effects of JHY-A007-50 on cancer cell proliferation, and JHY-A007-50 did not affect the cell viability of HeLa cells knocked down of TMEPAI. Conclusions: Taken together, these results suggest that compound JHY-A007-50 mediates the downregulation of TMEPAI expression and inhibits cell proliferation in cancer cells. [ABSTRACT FROM AUTHOR]

Fluorite (CaF2), as an important strategic mineral source, is usually separated from calcite by the common froth flotation method, but this separation is still not selective enough. The development of a selective collector and/or depressant is the key to achieving high selective separation. 1-Hydroxyethylidene-1,1-diphosphonic acid (HEDP or H4L) is widely used as an environmentally friendly water treatment reagent due to its low cost and excellent anti-scaling performance in an aqueous solution. In this study, a novel reagent scheme was developed using HEDP as a fluorite depressant and sodium oleate (NaOL) as a calcite collector for the first time. When 3 x 10-5 mol/L of HEDP and 6 x 10-5 mol/L of NaOL were used at pH 6, the optimal selective separation for single minerals and mixed binary minerals was obtained. Zeta potential measurements indicated that HEDP possessed a stronger adsorption on fluorite than calcite, while NaOL did the opposite. This novel reagent scheme is of low cost, uses a small dosage, and is friendly to the environment, which makes it a promising reagent scheme for fluorite flotation in industrial application. [ABSTRACT FROM AUTHOR]

By means of the restricted isometry property of order k and the restricted orthogonality property of order (k,k), this Letter mainly establishes an improved sufficient condition for a recently emerged ℓ1-2-minimisation to guarantee the robust signal recovery. The obtained condition is proved to be much better than the state-of-the-art ones for almost all parameters k. [ABSTRACT FROM AUTHOR]

Novel well-defined complex polymers, polymers of acetylene-type macromonomers having silylene-vinylene-phenylene-ethynylene hyperbranches, investigated as a new class of subnanoporous oxygen permselective membrane materials, were synthesized very easily by one-pot simultaneous two-mode homopolymerization of a single monomer with a single catalyst. For this "simultaneous polymerization" we synthesized AB2-type monomers (1,3-bis(dimethylsilyl)phenylacetylenes) containing one terminal triple bond and two Si-H groups. The resulting poly(hyperbranched macromonomer)s had high molecular weights, low densities, high solubility, and good self-membrane forming ability. They had higher oxygen permselectivities (α = PO2/PN2) than any other reported polymers having similar oxygen permeabilities (PO2). These excellent polymer membranes could be obtained only by the simultaneous polymerization. In the one-pot simultaneous polymerization, the two different modes of polymerizations, i.e., addition polymerization of the triple bond and polyaddition of the triple bond and two SiH groups in the single monomer, occurred simultaneously by using one catalytic system, i.e., [Rh(norbornadiene)Cl]2/various amines. The ratio of the branches (RB), i.e., the addition polymerization and the polyaddition, could be controlled by changing the amine cocatalysts. Their oxygen permselectivities could be adjusted by controlling the polymer structures including RB. [ABSTRACT FROM AUTHOR]

Objective: The present study aims to investigate whether the addition of homocysteine level to the Global Registry of Acute Coronary Events (GRACE) risk score enhances its predictive value for clinical outcomes in ST-elevation myocardial infarction (STEMI). Methods: A total of 1143 consecutive patients with STEMI were included in this prospective cohort study. Homocysteine was detected, and the GRACE score was calculated. The predictive power of the GRACE score alone or combined with homocysteine was assessed by the receiver operating characteristic (ROC) analysis, methods of net reclassification improvement (NRI) and integrated discrimination improvement (IDI). Results: During a median follow-up period of 36.7 months, 271 (23.7%) patients reached the clinical endpoints. It showed that the GRACE score and homocysteine could independently predict all-cause death [GRACE: HR=1.031 (1.024-1.039), p<0.001; homocysteine: HR=1.023 (1.018-1.028), p<0.001] and MACE [GRACE: HR=1.008 (1.005-1.011), p<0.001; homocysteine: HR=1.022 (1.018-1.025), p<0.001]. When they were used in combination to assess the clinical outcomes, the area under the ROC curve significantly increased from 0.786 to 0.884 (95% CI=0.067-0.128, Z=6.307, p<0.001) for all-cause death and from 0.678 to 0.759 (95% CI=0.055-0.108, Z=5.943, p<0.001) for MACE. The addition of homocysteine to the GRACE model improved NRI (all-cause death: 0.575, p<0.001; MACE: 0.621, p=0.008) and IDI (all-cause death: 0.083, p<0.001; MACE: 0.130, p=0.016), indicating effective discrimination and reclassification. Conclusion: Both the GRACE score and homocysteine are significant and independent predictors for clinical outcomes in patients with STEMI. A combination of them can develop a more predominant prediction for clinical outcomes in these patients. [ABSTRACT FROM AUTHOR]

Mood disturbances have been documented in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). The highly varied morbidity indicates that the affective symptoms in CADASIL have not been cataloged systematically, leading to ineffective treatment, affecting the patients' quality of life, and possibly resulting in suicide. We present a case of CADASIL with bipolar II disorder as the first manifestation. A middle-aged female reported recurrent depressive episodes and appeared treatment resistant to adequate dosages and durations of antidepressants. Following a structured psychiatric interview and neuropsychological assessment, a past episode of hypomania was identified. Added treatment with sodium valproate alleviated most symptoms. Considering late-onset bipolar disorder with unexplained decline in cognition, a medical history of migraine, and a suspected family history of stroke, further cranial magnetic resonance imaging scan was performed and revealed severe leukoencephalopathy, prompting further investigation. The diagnosis was revised to CADASIL after Arg587Cys NOTCH3 mutation was confirmed. This case highlights the evolving process of affective disorder diagnosis and underlying organic etiologies. Based on the overlap of white matter hyperintensities, NOTCH3 mutation, and valproate therapy in bipolar disorder and CADASIL, bipolar II depression may be a poorly recognized manifestation of CADASIL. Well-designed clinical trials are warranted to verify the current findings. [ABSTRACT FROM AUTHOR]

G protein-coupled receptors (GPCRs) regulate many animal behaviors. GPCR signaling is mediated by agonist-promoted interactions of GPCRs with heterotrimeric G proteins, GPCR kinases (GRKs), and arrestins. To further elucidate the role of GRKs in regulating GPCR-mediated behaviors, we utilized the genetic model system Caenorhabditis elegans. Our studies demonstrate that grk-2 loss-of-function strains are egg laying-defective and contain low levels of serotonin (5-HT) and high levels of the 5-HT metabolite 5-hydroxyindole acetic acid (5-HIAA). The egg laying defect could be rescued by the expression of wild type but not by catalytically inactive grk-2 or by the selective expression of grk-2 in hermaphrodite-specific neurons. The addition of 5-HT or inhibition of 5-HT metabolism also rescued the egg laying defect. Furthermore, we demonstrate that AMX-2 is the primary monoamine oxidase that metabolizes 5-HT in C. elegans, and we also found that grk-2 loss-of-function strains have abnormally high levels of AMX-2 compared with wild-type nematodes. Interestingly, GRK-2 was also found to interact with and promote the phosphorylation of AMX-2. Additional studies reveal that 5-HIAA functions to inhibit egg laying in a manner dependent on the 5-HT receptor SER-1 and the G protein GOA-1. These results demonstrate that GRK-2 modulates 5-HT metabolism by regulating AMX-2 function and that 5-HIAA may function in the SER-1 signaling pathway. [ABSTRACT FROM AUTHOR]

The spatial structure and underlying assembly mechanisms of bacterial communities have been studied widely across aquatic systems, focusing primarily on isolated sites, such as different lakes, ponds and streams. Here, our main aim was to determine the underlying mechanisms for bacterial biofilm assembly within a large, highly connected lake system in Northern Finland using associative methods based on taxonomic and phylogenetic alpha- and beta-diversity and a large number of abiotic and biotic variables. Furthermore, null model approaches were used to quantify the relative importance of different community assembly processes. We found that spatial variation in bacterial communities within the lake was structured by different assembly processes, including stochasticity, species sorting and potentially even dispersal limitation. Species sorting by abiotic environmental conditions explained more of the taxonomic and particularly phylogenetic turnover in community composition compared with that by biotic variables. Finally, we observed clear differences in alpha diversity (species richness and phylogenetic diversity), which were to a stronger extent determined by abiotic compared with biotic factors, but also by dispersal effects. In summary, our study shows that the biodiversity of bacterial biofilm communities within a lake ecosystem is driven by within-habitat gradients in abiotic conditions and by stochastic and deterministic dispersal processes. [ABSTRACT FROM AUTHOR]

Tumor invasion and metastasis are the critical steps in determining the aggressive phenotype of human cancers. Melittin, a major component of bee venom, has been reported to induce apoptosis in several cancer cells. However, the mechanisms of melittin involvement in cancer invasion and metastasis remain unclear. Our previous study indicated that melittin inhibits cyclophilin A (CypA), a ubiquitously distributed peptidylprolyl cis-trans isomerase, in macrophage cells. In the present study, the Transwell assay results showed that melittin may downregulate the invasion level of MCF-7 cells in a dose-dependent manner. Additionally, it was also found, using flow cytometry and reverse transcription-polymerase chain reaction, that melittin decreased the expression of cluster of differentiation (CD)147 and matrix metallopeptidase-9 (MMP-9), whereas CypA upregulated the expression of CD147 and MMP-9. Overall, the present study indicated that melittin decreased the invasion level of MCF-7 cells by downregulating CD147 and MMP-9 by inhibiting CypA expression. The results of the present study provide an evidence for melittin in anticancer therapy and mechanisms. [ABSTRACT FROM AUTHOR]

Promiscuous enzymes are generally considered to be starting points in the evolution of offspring enzymes with more specific or even novel catalytic activities, which is the molecular basis of producing new biological functions. Mhg, a typical α/β fold hydrolase, was previously reported to have both γ-lactamase and perhydrolase activities. However, despite having high structural similarity to and sharing an identical catalytic triad with an extensively studied esterase from Pseudomonas fluorescens, this enzyme did not show any esterase activity. Molecular docking and sequence analysis suggested a possible role for the entry of the binding pocket in blocking the entrance tunnel, preventing the ester compounds from entering into the pocket. By engineering the entrance tunnel with only one or two amino acid substitutions, we successfully obtained five esterase variants of Mhg. The variants exhibited a very broad substrate acceptance, hydrolyzing not only the classical p-nitrophenol esters but also various types of chiral esters, which are widely used as drug intermediates. Site 233 at the entrance tunnel of Mhg was found to play a pivotal role in modulating the three catalytic activities by adjusting the size and shape of the tunnel, with different amino acid substitutions at this site facilitating different activities. Remarkably, the variant with the L233G mutation was a very specific esterase without any γ-lactamase and perhydrolase activities. Considering the amino acid conservation and differentiation, this site could be a key target for future protein engineering. In addition, we demonstrate that engineering the entrance tunnel is an efficient strategy to regulate enzyme catalytic capabilities. [ABSTRACT FROM AUTHOR]

An efficient asymmetric total synthesis of the dimeric macrocyclic diaryl ether phenethyltetrahydroisoquinoline alkaloid (-)-melanthiodine is reported. Key steps of the synthesis include an efficient Noyori asymmetric transfer hydrogenation to access the enantioenriched phenethyltetrahydroisoquinoline monomeric subunit and a copper-mediated cyclodimerization to form the two diaryl ether linkages with concomitant macrocyclization. [ABSTRACT FROM AUTHOR]

In this study,the entropy weight method was used to comprehensively evaluate the eight sweet-glutinous maize varieties in the regional trials in Shanxi Province in 2016. The results showed that the order of the performance of comprehensive traits of the tested varieties was Heitiannuo 631,Heitiannuo No. 2,Cainuo No. 5,Xinnuo 8601,FYN 1601,Xinnuo 8608,Jindannuo 41,Caitiannuo 1958( from good to poor). Among them,Heitiannuo 631,Heitiannuo No. 2 and Cainuo No. 5 are excellent varieties,and the rest are good varieties. [ABSTRACT FROM AUTHOR]

As a fast-growing sector of the healthcare industry, Ambulatory Surgery Centers (ASC) offer timely and cost-saving services in public health. In this study, large-scale data from the American Community Survey and the Office of Statewide Health Planning and Development (OSHPD) are merged to examine factors of ASC access on multiple dimensions. The analytic method conforms to a well-established CIPP paradigm to justify results-based accountability on what works, for whom, and in which context. While identifying significant impact of family income, population density, and early childhood support, this study further reveals a moderate effect of health insurance coverage on ASC access. [ABSTRACT FROM AUTHOR]

As ambulatory surgery centers experience rapid development in recent years, service access has been identified as an important outcome measure that demands methodological considerations to support multilevel analyses. In this study, a literature review was conducted to illustrate existence of contextual factors, such as Proposition 10 funding for young children and tax incentives in high-need communities, which directly impacts the local capacity building. Variance of the service access has been partitioned at both county and community levels to reconfirm the need for multilevel studies. In comparison to randomized clinical trials in medical research, multilevel analyses can add contextual information to enhance examination of the hierarchical data structure in which communities are naturally nested within counties. [ABSTRACT FROM AUTHOR]

Constraints on conventional access delegation rules on mobile nodes (MNs) are simple. The overall fuzzy evaluation is used to integrate the trust risk that is assessed based on the historical access information within a cellular interval, the context risk assessed based on the position temporal and the information leakage risk assessed based on the node density and the overlapped area, into the access delegation risk of MNs, so as to expand the access delegation rules for MNs and improves the rules with respect to flexibility and security. Finally, an example is used to validate the risk evaluation process. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the underlying mechanisms of methotrexate (MTX) resistance in the human osteosarcoma cell line, Saos-2/MTX4.4, and to evaluate various methods of overcoming the resistance to this chemotherapeutic agent. MMT assays were performed to determine the resistance of the primary (Saos-2) and resistant (Saos-2/MTX4.4) cell lines to MTX, cisplatin [cis-diamminedichloroplatinum II (DDP)], ifosfamide (IFO), Adriamycin (ADM), epirubicin (EPI) and theprubicin (THP). The Saos-2/MTX4.4 cells exhibited a low resistance to IFO, ADM, EPI and THP; however, no resistance to DDP was identified. Overall, the Saos-2/MTX4.4 cells exhibited a greater resistance to all the chemotherapeutic agents investigated compared with the Saos-2 cells. Rhodamine 123 (R123) fluorescence was measured in the Saos-2/MTX4.4 and Saos-2 cells 30 and 60 min after the addition of R123, and R123 plus verapamil (VER). VER administration increased the intracellular accumulation of R123. In addition, reverse transcription-quantitative polymerase chain reaction was performed to determine the mRNA expression levels of multidrug resistance gene 1 (MDR1) in the two cell lines. Although the Saos-2/MTX4.4 cells were more resistant to the chemotherapeutic agents than the Saos-2 cells, no significant difference was identified between the relative mRNA expression levels of MDR1 in the Saos-2/MTX4.4 and Saos-2 cells (0.4350±0.0354 vs. 0.3886±0.0456; P>0.05). [ABSTRACT FROM AUTHOR]

A major challenge in palaeohydrology is the extraction of continuous palaeoflood information from geophysical records. A high-resolution sediment core off the Minjiang estuary area in the Taiwan Strait, SE China, records the sedimentation history from approximately 1660 to the present. The alkane ratio C31/C17, a classic organic geochemical indicator of terrestrial/aquatic matter, peaks in the layers dating as 1876-1878 and 1968-1970, suggesting the large terrestrial input to the Minjiang estuary area by huge flood transporting during the each peak interval. Historical archives are consistent with this interpretations and record catastrophic floods in the Minjiang River during both intervals. Furthermore between 1876-1878 there were floods in southern China and droughts in northern China, as well as throughout Asia, Africa, Australia, and the Americas. The 1876-1878 catastrophic flood of the Minjiang River may therefore has been the local response to global climate anomalies during that time interval. [ABSTRACT FROM AUTHOR]

Background: The clinical significance of metastasis associated in colon cancer 1 (MACC1), in human gallbladder cancer, is not yet established. This study was performed to assess the expression of MACC1 in benign and malignant gallbladder lesions, and to assess its clinicopathological significance. Materials and Methods: Tissue samples from resected gallbladder cancer (n = 70) and cholelithiasis (n = 70) were evaluated for MACC1 expression by immunohistochemical staining. Their expression was correlated with different clinicopathological parameters. Results: Cytoplasmic MACC1 expression was significantly higher (58.6%) in gallbladder cancer than in chronic cholecystitis (27.1%, P < 0.001). High MACC1 levels were associated with lymph node metastasis (P < 0.05), tumor node metastasis (TNM) stage (P < 0.01), and perineural invasion (P < 0.01), but not with sex, age, history of gallstones or histological grade (P > 0.05). The univariate Kaplan-Meier analysis showed that a positive MACC1 expression was associated with decreased overall survival (P < 0.001). The multivariate Cox regression analysis showed that MACC1 expression and the histopathological subtypes were independent risk factors for disease-free survival. Conclusion: The expression of MACC1 might be closely related to carcinogenesis, clinical biological behaviors, and prognosis of gallbladder adenocarcinoma. [ABSTRACT FROM AUTHOR]

Differentially-expressed genes (DEGs) correlated to oral contraceptives (OCs) were identified by comparing the transcriptomes of cervical cancer patients who have taken OCs and those who have not. Their biological functions and relevance to clinical manifestations were investigated further in order to gain an understanding of the pathogenesis of cervical cancer and provide potential therapeutic targets. Level 3 RNA-sequencing (seq) data for cervical squamous-cell carcinoma and endocervical adenocarcinoma and the clinical information were downloaded from The Cancer Genome Atlas. The present study analyzed the RNA-seq data and information on OC use of 35 patients [OC users (n=18) and those who have never used OCs (n=17)]. Student's t-test was used in order to identify DEGs and the false discovery rate (FDR) was estimated by a Beta-Uniform Mixture model, which was adopted in multiple testing corrections. A functional enrichment analysis was performed with the Database for Annotation, Visualization and Integrated Discovery tool and BioCarta. A total of 80 DEGs were identified in OC users while FDR=0.3 was set as the cut-off value. The metabolic process and human telomerase RNA gene transcription were significantly upregulated in DEGs. Furthermore, secreted LY6/PLAUR domain containing 1 was identified to be correlated to the pathological response, while the synapse defective 1 Rho GTPase homolog 2 was found to be significantly associated with the histological grade and overall survival time. In conclusion, present study shed light on the effect of OC use on the oncogenesis of the cervix and may indicate novel approaches for a targeted therapy of cervical cancer. [ABSTRACT FROM AUTHOR]

An environmentally benign and efficient method has been developed for the synthesis of functionalized tetrahydroindole derivatives in aqueous media under catalyst-free conditions, by simply combining a phenylglyoxal monohydrate, an enaminone, and a barbituric acid. The advantages of this method are that it is catalyst free, has an easy workup, provides good yields, and uses water as solvent, which make this procedure facile and practical. [ABSTRACT FROM AUTHOR]

Vascular endothelial leukocyte adhesion molecules, such as E-selectin, are acutely upregulated in myocardial ischemia/reperfusion and are thus "ischemic memory" biomarkers for recent cardiac ischemia. We sought to develop an ultrasound molecular imaging agent composed of microbubbles (MBs) targeted to E-selectin to enable the differential diagnosis of myocardial ischemia in patients presenting with chest pain of unclear etiology. Biodegradable polymer MBs were prepared bearing a peptide with specific human E-selectin affinity (MBESEL). Control MBs had scrambled peptide (MBCTL) or nonspecific IgG (MBIgG). MBESEL adhesion to activated rat endothelial cells (ECs) was confirmed in vitro in a flow system and in vivo with intravital microscopy of rat cremaster microcirculation. Ultrasound molecular imaging of recent myocardial ischemia was performed in rats 4 hours after transient (15 minutes) coronary occlusion. MBESEL adhesion was higher to inflamed versus normal ECs in vitro; there was no difference in MBCTL or MBIgG adhesion to inflamed versus normal ECs. There was greater adhesion of MBESEL to inflamed versus noninflamed microcirculation and minimal adhesion of MBCTL or MBIgG under any condition. Ultrasound imaging after injection of MBSEL demonstrated persistent contrast enhancement of the previously ischemic region. Videointensity in postischemic myocardium after MBESEL was higher than that in the nonischemic bed (11.6 ± 2.7 dB vs 3.6 6 0.8 dB, p <. 02) and higher than that after MBCTL (4.0 ± 1.0 dB, p < .03) or MBIgG (1.7 ± 0.1 dB, p < .03). MBs targeted to E-selectin via a short synthetic peptide with human E-selectin binding affinity enables echocardiographic detection of recent ischemia, setting the stage for clinical myocardial ischemic memory imaging to identify acute coronary syndromes. [ABSTRACT FROM AUTHOR]

Background γ-lactamase is used for the resolution of γ-lactam which is utilized in the synthesizing of abacavir and peramivir. In some cases, enzymatic method is the most utilized method because of its high efficiency and productivity. The cellulose binding domain (CBD) of cellulose is often used as the bio-specific affinity matrix for enzyme immobilization. Cellulose is cheap and it has excellent chemical and physical properties. Meanwhile, binding between cellulose and CBD is tight and the desorption rarely happened. Results We prepared two fusion constructs of the γ-lactamase gene gla, which was from Sulfolobus solfataricus P2. These two constructs had Cbd (cellulose binding domain from Clostridium thermocellum) fused at amino or carboxyl terminus of the γ-lactamase. These two constructs were heterogeneously expressed in E. coli rosetta (DE3) as two fusion proteins. Both of them were immobilized well on Avicel (microcrystalline cellulose matrix). The apparent kinetic parameters revealed that carboxyl terminus fused protein (Gla-linker-Cbd) was a better catalyst. The Vmax and kcat value of Avicel immobilized Gla-linker-Cbd were 381 U mg-1 and 4.7 × 105 s-1 respectively. And the values of the free Gla-linker-Cbd were 151 U mg-1 and 1.8 × 105 s-1 respectively. These data indicated that the catalytic efficiency of the enzyme was upgraded after immobilization. The immobilized Gla-linker-Cbd had a 10-degree temperature optimum dropping from 80°C to 70°C but it was stable when incubated at 60°C for 48 h. It remained stable in catalyzing 20-batch reactions. After optimization, the immobilized enzyme concentration in transformation was set as 200 mg/mL. We found out that there was inhibition that occurred to the immobilized enzyme when substrate concentration exceeded 60 mM. Finally a 10 mL-volume transformation was conducted, in which 0.6 M substrate was hydrolyzed and the resolution was completed within 9 h with a 99.5% ee value. Conclusions Cellulose is the most abundant and renewable material on the Earth. The absorption between Cbd domain and cellulose is a bio-green process. The cellulose immobilized fusion Gla exhibited good catalytic characters, therefore we think the cellulose immobilized Gla is a promising catalyst for the industrial preparation of (-) - γ-lactam. [ABSTRACT FROM AUTHOR]

We present a probabilistic analysis on conditions of the exact recovery of block-sparse signals whose nonzero elements appear in fixed blocks. We mainly derive a simple lower bound on the necessary number of Gaussian measurements for exact recovery of such block-sparse signals via the mixed l2/lq (0 < q ≤ 1) norm minimization method. In addition, we present numerical examples to partially support the correctness of the theoretical results. The obtained results extend those known for the standard lq minimization andthe mixed 12/11 minimization methods to the mixed l2/lq (0 < q ≤ 1) minimization method in the context of block-sparse signal recovery. [ABSTRACT FROM AUTHOR]

The containment is an ultimate and important barrier to mitigate the consequences after the release of mass and energy during such scenarios as loss of coolant accident (LOCA) or main steamline break (MSLB). In this investigation, a passive containment cooling system (PCCS) concept is proposed for a large dry concrete containment. The system is composed of series of heat exchangers, long connecting pipes with relatively large diameter, valves, and a water tank, which is located at the top of the system and serves as the final heat sink. The performance of the system is numerically studied in detail under different conditions. In addition, the influences of condensation heat transfer conditions and containment environment temperature conditions are also studied on the behaviors of the system. The results reveal that four distinct operating stages could be experienced as follows: startup stage, single phase quasisteady stage, flashing speed-up transient stage, and flashing dominated quasisteady operating stage. Furthermore, the mechanisms of system behaviors are thus analyzed. Moreover, the feasibility of the system is also discussed to meet the design purpose for the containment integrity requirement. Considering the passive feature and the compactness of the system, the proposed PCCS is promising for the advanced integral type reactor. [ABSTRACT FROM AUTHOR]

Elephantopus scaber is an ethnomedicinal plant used by the Zhuang people in Southwest China to treat headaches, colds, diarrhea, hepatitis, and bronchitis. A new δ-truxinate derivative, ethyl, methyl 3,4,3',4'-tetrahydroxy-δ-truxinate (1), was isolated from the ethyl acetate extract of the entire plant, along with 4 known compounds. The antioxidant activity of these 5 compounds was determined by ABTS radical scavenging assay. Compound 1 was also tested for its cytotoxicity effect against HepG2 byMTT assay (IC50 = 60μM), and its potential anti-inflammatory, antibiotic, and antitumor bioactivities were predicted using target fishing method software. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effects of combination of linseed oil (rich in omega 3 polyunsaturated fatty acid, ω3 PUFA) and palm oil (rich in saturated fatty acid, SFAs) on the growth performance, meat quality, and fatty acid composition of birds under high environmental temperature. Experiment was conducted in summer (average high temperature 31°C). Birds in the positive temperature control group (PTC) and negative temperature control group (NTC) were fed with maize-soybean meal-maize gluten basal diet, the other 4 experimental groups were fed with basal diets containing linseed oil (LO), palm oil (PO), or their combination at the ratio of 3:2 (linseed oil/palm oil, w/w, group LPI) or 2:3 (group LPII), respectively. Results showed that the NTC deleteriously affect the growth performance, carcass quality and fatty acid composition of chickens than PTC group. The growth performance of birds under high environmental temperature was improved by oil supplementation. Furthermore, the combination of both oils achieved a better growth performance than the single oil during 22 to 42 d. Compared with NTC group, the yields of breast, leg and carcass were significantly improved in group LPI. Fatty acid composition of meat was significantly modified by dietary oil, and PUFA, especially ω3 PUFA in meat was increased by linseed oil (P<0.05). However, the MUFA and SFA contents in meat were not positively correlated with their contents in diet. Birds fed with combined oil at the ratio of 2:3 (w/w) achieved better economic results. It was concluded that the combination of linseed and palm oils at 2:3 (w/w) in chicken diets had more positive effect on growth performance, enhanced the n-3 PUFA content in meat, and economically better than single dietary oil. [ABSTRACT FROM AUTHOR]

In this work, we present a theoretical method to determine the line tension of nanodroplets on homogeneous substrates via decomposing the grand free energy into volume, interface and line contributions. With the obtained line tension, we check the viability of Young equation and find that the chemical potential dependence (or equivalently, droplet curvature dependence) of the interface tensions is crucial for the viability of modified Young equation at the nanometer scale. In particular, the linear relationship between the cosine of contact angle and the curvature of the contact line, which is often used to determine the line tension, is found to be incorrect at the nanometer scale. [ABSTRACT FROM AUTHOR]

We introduce a technique for measuring the conductivity of individual hybrid metal, semiconducting core-shell and full-metal conducting particles by a microscopic four-point probe (m-4PP) method. The four-point probe geometry allows for minimizing contact resistances between electrodes and particles. By using a focused ion beam we fabricate platinum nanoleads between four microelectrodes on a silicon chip and an individual particle, and determine the particle's conductivity via sensitive current and voltage measurements. Up to sixteen particles can be taken up by each chip, which allows for multiple conductivity measurements by simply multiplexing the electric contacts connected to a multimeter. Although, for demonstration, we used full Au (conducting) and Ag-coated latex particles (semiconducting) of a few micrometers in diameter, the method can be applied to other types of conducting or semiconducting particles of different diameters. [ABSTRACT FROM AUTHOR]

The formation of Cu2SnSe3 tetrapod nanocrystals is reported using a hot injection colloidal synthesis. The ternary copper chalcogenide nanocrystals nucleate with a cubic core with four short wurzite arms. [ABSTRACT FROM AUTHOR]

We first give the unboundedness of multivariate Baskakov operators with the normal weighted norm. By introducing new norms, using the multivariate decomposition technique and the modulus of smoothness with Jacobi weight, the upper bound estimation of multivariate Baskakov operators is obtained. The obtained results not only generalize the corresponding ones for multivariate Baskakov operators without weights, but also give the approximation accuracy with the Jacobi weights approximation. [ABSTRACT FROM AUTHOR]

This note discusses the recovery of signals from undersampled data in the situation that such signals are nearly block sparse in terms of an overcomplete and coherent tight frame D. By introducing the notion of block D-restricted isometry property (D-RIP), we establish several sufficient conditions for the proposed mixed l2/l1-analysis method to guarantee stable recovery of nearly block sparse signals in terms of D. One of the main results of this note shows that if the measurement matrix satisfies the block D-RIP with constants δk< 0.307, then the signals which are nearly block k-sparse in terms of D can be stably recovered via mixed l2/l1-analysis in the presence of noise. [ABSTRACT FROM AUTHOR]

A system composed of coupled FitzHugh-Nagumo neurons with various topological structures is investigated under the co-presence of two independently additive and multiplicative Gaussian white noises, in which particular attention is paid to the neuronal networks spiking regularity. As the additive noise intensity and the multiplicative noise intensity are simultaneously adjusted to optimal values, the temporal periodicity of the output of the system reaches the maximum, indicating the occurrence of doubly stochastic coherence. The network topology randomness exerts different influences on the temporal coherence of the spiking oscillation for dissimilar coupling strength regimes. At a small coupling strength, the spiking regularity shows nearly no difference in the regular, small-world, and completely random networks. At an intermediate coupling strength, the temporal periodicity in a small-world neuronal network can be improved slightly by adding a small fraction of long-range connections. At a large coupling strength, the dynamical behavior of the neurons completely loses the resonance property with regard to the additive noise intensity or the multiplicative noise intensity, and the spiking regularity decreases considerably with the increase of the network topology randomness. The network topology randomness plays more of a depressed role than a favorable role in improving the temporal coherence of the spiking oscillation in the neuronal network research study. [ABSTRACT FROM AUTHOR]

The formulas for error propagation from the random error sources to the three-dimensional (3-D) coordinate errors of laser footprints of an airborne laser scanning (ALS) system were deduced. Based on large-scale sample data, multiple linear regression experiments were carried out to obtain the standardized regression coefficients of the random errors for the 3-D coordinate errors under different flight heights (from 500 to 6000 m above ground level). The standardized regression coefficients were used to quantitatively evaluate the impacts of the random errors and to sort the impacts on the order of importance. The variation of the impacts of the random errors with increasing flight height and tilt angle of the mirror was also analyzed. The experimental results provide an important guide for error budget of various sensors in the ALS system so as to effectively suppress or compensate significant errors and to improve the performance of the ALS system. [ABSTRACT FROM AUTHOR]

Ryanodine receptors (RyRs) are the targets of two novel classes of synthetic insecticidal chemicals, phthalic acid diamides and anthranilic diamides. Isolation of full-length RyR cDNAs is a critical step towards the structural and functional characterization of insect RyRs and an understanding of the molecular mechanisms underlying the species selective toxicity of diamide insecticides. However, there has been little research on the insect RyR genes due to the high molecular weight of the RyR proteins. In this study, we isolated a full-length RyR cDNA (named as CmRyR) from Cnaphalocrocis medinalis, an important rice pest throughout Southeast Asia. The composite CmRyR gene contains an ORF of 15264 bp encoding a protein of 5087 amino acid residues, which shares 79% overall identity with its Drosophila melanogaster homologue. All hallmarks of the RyR proteins are conserved in the CmRyR protein, suggesting that CmRyR is a structural and functional analogue of known RyRs. A multiple sequence alignment illustrates that the insect RyRs share high levels of amino acid sequence identity at the the COOH-terminal region. However, the amino acid residues analogous to the CmRyR residues N4922, N4924, N4935, L4950, L4981, N5013 and T5064 are unique to lepidopteran RyRs compared with non-lepidopteran insect RyRs. This finding suggests that these residues may be involved in the differences in channel properties between lepidopteran and non-lepidopteran insect RyRs and in the species selective toxicity of diamide insecticides. Furthermore, two alternative splicing sites were identified in the CmRyR gene, one of which was located in the central part of the predicted second SPRY domain. Diagnostic PCR showed that the inclusion frequencies of two mutually exclusive exons (a/b) and one optional exon (c) differed between developmental stages or adult anatomical regions. Our results imply that alternative splicing may be a major means of generating functional diversity in C. medinalis RyR channel. [ABSTRACT FROM AUTHOR]

Although more than 120 families of short interspersed nuclear elements (SINEs) have been isolated from the eukaryotic genomes, little is known about SINEs in insects. Here, we characterize three novel SINEs from the cotton bollworm, Helicoverpa armigera. Two of them, HaSE1 and HaSE2, share similar 5' -structure including a tRNA-related region immediately followed by conserved central domain. The 3' -tail of HaSE1 is significantly similar to that of one LINE retrotransposon element, HaRTE1.1, in H. armigera genome. The 3' -region of HaSE2 showed high identity with one mariner-like element in H. armigera. The third family, termed HaSE3, is a 5S rRNA-derived SINE and shares both body part and 3'-tail with HaSE1, thus may represent the first example of a chimera generated by recombination between 5S rRNA and tRNA-derived SINE in insect species. Further database searches revealed the presence of these SINEs in several other related insect species, but not in the silkworm, Bombyx mori, indicating a relatively narrow distribution of these SINEs in Lepidopterans. Apart from above, we found a copy of HaSE2 in the GenBank EST entry for the cotton aphid, Aphis gossypii, suggesting the occurrence of horizontal transfer. [ABSTRACT FROM AUTHOR]

Using the modulus of smoothness, directional derivatives of multivariate Bernstein operators with weights are characterized. The obtained results partly generalize the corresponding ones for multivariate Bernstein operators without weights. [ABSTRACT FROM AUTHOR]

The history of curriculum reform from 1978 to 2008 in mainland China may be divided into three phases, each-respectively-committed to the recovery of the curriculum system ruined by the Cultural Revolution, construction of a curriculum system in concert with the nine-year compulsory education, and pursuit of quality education under the changed economic and social context from the late 1990s. Conflicts in the conception and practice of curriculum piled up during the process of curriculum reform and finally became apparent in the recent curriculum reform. [ABSTRACT FROM AUTHOR]

It is widely accepted that biodiversity is lower in more extreme environments. In this study, we sought to determine whether this trend, well documented for macroorganisms, also holds at the microbial level for bacteria. We used denaturing gradient gel electrophoresis (DGGE) with phylum-specific primers to quantify the taxon richness (i.e., the DGGE band numbers) of the bacterioplankton communities of 32 pristine Tibetan lakes that represent a broad salinity range (freshwater to hypersaline). For the lakes investigated, salinity was found to be the environmental variable with the strongest influence on the bacterial community composition. We found that the bacterial taxon richness in freshwater habitats increased with increasing salinity up to a value of 1‰. In saline systems (systems with >1‰ salinity), the expected decrease of taxon richness along a gradient of further increasing salinity was not observed. These patterns were consistently observed for two sets of samples taken in two different years. A comparison of 16S rRNA gene clone libraries revealed that the bacterial community of the lake with the highest salinity was characterized by a higher recent accelerated diversification than the community of a freshwater lake, whereas the phylogenetic diversity in the hypersaline lake was lower than that in the freshwater lake. These results suggest that different evolutionary forces may act on bacterial populations in freshwater and hypersaline lakes on the Tibetan Plateau, potentially resulting in different community structures and diversity patterns. [ABSTRACT FROM AUTHOR]