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Summary: In contrast to CUT&Tag approaches for profiling bulk histone modifications, current CUT&Tag methods for analysing specific transcription factor (TF)‐DNA interactions remain technically challenging due to TFs having relatively low abundance. Moreover, an efficient CUT&Tag strategy for plant TFs is not yet available. Here, we first applied biotinylated Tn5 transposase‐mediated CUT&Tag (B‐CUT&Tag) to produce high‐quality libraries for interrogating TF‐DNA interactions. B‐CUT&Tag combines streptavidin‐biotin‐based DNA purification with routine CUT&Tag, optimizing the removal of large amounts of intact chromatin not targeted by specific TFs. The biotinylated chromatin fragments are then purified for construction of deep sequencing libraries or qPCR analysis. We applied B‐CUT&Tag to probe genome‐wide DNA targets of Squamosa promoter‐binding‐like protein 9 (SPL9), a well‐established TF in Arabidopsis; the resulting profiles were efficient and consistent in demonstrating its well‐established target genes in juvenile‐adult transition/flowering, trichome development, flavonoid biosynthesis, wax synthesis and branching. Interestingly, our results indicate functions of AtSPL9 in modulating growth‐defence trade‐offs. In addition, we established a method for applying qPCR after CUT&Tag (B‐CUT&Tag‐qPCR) and successfully validated the binding of SPL9 in Arabidopsis and PHR2 in rice. Our study thus provides a convenient and highly efficient CUT&Tag strategy for profiling TF‐chromatin interactions that is widely applicable to the annotation of cis‐regulatory elements for crop improvement. [ABSTRACT FROM AUTHOR]

In recent years, some peptide ligases have been identified, such as bacterial sortases and certain plant asparaginyl or prolyl endopeptidases. Peptide ligases have wide applications in protein labelling and cyclic peptide synthesis. To characterize various known peptide ligases or identify new ones, we propose a general bioluminescent activity assay via the genetic fusion of a recognition motif of peptide ligase(s) to the C‐terminus of an inactive large NanoLuc fragment (LgBiT) and the chemical introduction of a nucleophilic motif preferred by the peptide ligase(s) to the N‐terminus of the low‐affinity SmBiT complementation tag. After the inactive ligation version LgBiT protein was ligated with the low‐affinity ligation version SmBiT tag by the expected peptide ligase(s), its luciferase activity would be restored and could be quantified sensitively according to the measured bioluminescence. In the present study, we first validated the bioluminescent activity assay using bacterial sortase A and plant‐derived butelase‐1. Subsequently, we screened novel peptide ligases from crude extracts of selected plants using two LgBiT‐SmBiT ligation pairs. Among 80 common higher plants, we identified that five of them likely express asparaginyl endopeptidase‐type peptide ligase and four of them likely express prolyl endopeptidase‐type peptide ligase, suggesting that peptide ligases are not so rare in higher plants and more of them await discovery. The present bioluminescent activity assay is ultrasensitive, convenient for use, and resistant to protease interference, and thus would have wide applications for characterizing known peptide ligases or screening new ones from various sources in future studies. [ABSTRACT FROM AUTHOR]

Demographic compensation—the opposing responses of vital rates along environmental gradients—potentially delays anticipated species' range contraction under climate change, but no consensus exists on its actual contribution. We calculated population growth rate (λ) and demographic compensation across the distributional ranges of 81 North American tree species and examined their responses to simulated warming and tree competition. We found that 43% of species showed stable population size at both northern and southern edges. Demographic compensation was detected in 25 species, yet 15 of them still showed a potential retraction from southern edges, indicating that compensation alone cannot maintain range stability. Simulated climatic warming caused larger decreases in λ for most species and weakened the effectiveness of demographic compensation in stabilising ranges. These findings suggest that climate stress may surpass the limited capacity of demographic compensation and pose a threat to the viability of North American tree populations. [ABSTRACT FROM AUTHOR]

The management of biological invasions is a worldwide conservation priority. Unfortunately, decision‐making on optimal invasion management can be impeded by lack of information about the biological processes that determine invader success (i.e. biological uncertainty) or by uncertainty about the effectiveness of candidate interventions (i.e. operational uncertainty). Concurrent assessment of both sources of uncertainty within the same framework can help to optimize control decisions.Here, we present a Value of Information (VoI) framework to simultaneously analyse the effects of biological and operational uncertainties on management outcomes. We demonstrate this approach with a case study: minimizing the long‐term population growth of musk thistle Carduus nutans, a widespread invasive plant, using several insects as biological control agents, including Trichosirocalus horridus, Rhinocyllus conicus and Urophora solstitialis.The ranking of biocontrol agents was sensitive to differences in the target weed's demography and also to differences in the effectiveness of the different biocontrol agents. This finding suggests that accounting for both biological and operational uncertainties is valuable when making management recommendations for invasion control. Furthermore, our VoI analyses show that reduction of all uncertainties across all combinations of demographic model and biocontrol effectiveness explored in the current study would lead, on average, to a 15.6% reduction in musk thistle population growth rate. The specific growth reduction that would be observed in any instance would depend on how the uncertainties actually resolve. Resolving biological uncertainty (across demographic model combinations) or operational uncertainty (across biocontrol effectiveness combinations) alone would reduce expected population growth rate by 8.5% and 10.5% respectively.Synthesis and applications. Our study demonstrates that intervention rank is determined both by biological processes in the targeted invasive populations and by intervention effectiveness. Ignoring either biological uncertainty or operational uncertainty may result in a suboptimal recommendation. Therefore, it is important to simultaneously acknowledge both sources of uncertainty during the decision‐making process in invasion management. The framework presented here can accommodate diverse data sources and modelling approaches, and has wide applicability to guide invasive species management and conservation efforts. [ABSTRACT FROM AUTHOR]

Plant populations may have evolved different demographic strategies to cope with temporal environmental variation. According to the demographic buffering hypothesis, vital rates that are most critical to population persistence are buffered against environmental variation and vary little over time, whereas the demographic lability hypothesis suggests that populations may track and benefit from environmental variation. While the hypotheses of demographic strategies have been widely tested in plant and animal species, they have not been explicitly examined for invasive plants, or in relation to different modelling methods (deterministic vs. stochastic). Here, we tested the demographic buffering and lability hypotheses for 23 populations of eight invasive plant species in relation to life form (woody vs. herbaceous species) and population growth rate using deterministic and stochastic modelling methods, and absolute and relative scales. We found that conclusions of demographic strategies depended on scale, with an absolute scale resulting in stronger negative correlations between the variability and importance of vital rates (i.e., buffering) than a relative scale. Conclusions of demographic strategies were also affected by life form that interacted with method. The populations of woody invaders exhibited buffering regardless of the method used, while for the populations of herbaceous species, deterministic calculations suggested buffering and stochastic calculations suggested lability. Overall, our findings emphasise the role of life form and methodological issues that need to be considered when exploring demographic strategies in fluctuating environments. [ABSTRACT FROM AUTHOR]

Grazing by livestock is a common land use in arid and semi-arid areas. Developing sustainable grazing regimes that conserve vegetation and maintain productivity is therefore important in these ecosystems. To solve environmental problems induced by overgrazing in Chinese semi-arid regions, the Chinese government has recently implemented a new policy of seasonal grazing, with no grazing from April to July. While this policy has been implemented in huge areas, its consequences for grazed plant populations have not been assessed so far., We evaluated the demographic consequences of seasonal grazing for Caragana intermedia, a long-lived dominant shrub serving as a main food source for livestock in Inner Mongolia, China. Controlled seasonally grazed and ungrazed populations were monitored during 2007-2009, and their vital rates were compared. We then constructed integral projection models ( IPMs) to analyse the effects of seasonal grazing on population dynamics., Seasonal grazing negatively affected two vital rates: seedling survival and seedling recruitment were 25-71% and 69-91% lower in the seasonally grazed treatment than in the ungrazed situation, respectively. Seasonal grazing had a minimal effect on adult survival and growth, but improved juvenile survival by 8-31%., Despite its effects on several vital rates, seasonal grazing did not significantly affect long-term population growth rates (λ), which remained close to unity in both grazed and ungrazed areas based on deterministic and stochastic analyses. An elasticity analysis showed that population growth rate was mainly governed by the high survival of large adults. Results of Life Table Response Experiments ( LTREs) revealed that variation in population growth rates across treatments and years was more strongly governed by temporal differences than by grazing., Synthesis and applications. Our study showed that the relatively large changes in vital rates induced by seasonal grazing did not affect population growth rates. Caragana intermedia populations can be sustained under the seasonal grazing regime probably because the grazing intensity is moderate and because this species has a high probability of adult survival under grazing. Plant species with similar life-history traits to C. intermedia are likely to offer good opportunities for sustainable seasonal grazing regimes in arid and semi-arid inland ecosystems. [ABSTRACT FROM AUTHOR]

Three new triterpenoids, 21 β,22 α-diangeloyloxy-3 β,15 α,16 α,28-tetrahydroxyolean-12-en-23-al ( 1), 21 β-angeloyloxy-3 β,15 α,16 α,28-tetrahydroxy-22 α-(2-methylbutanoyloxy)olean-12-en-23-al ( 2), and 21 β-angeloyloxy-3 β,16 α,28-trihydroxy-22 α-(2-methylbutanoyloxy)olean-12-en-23-al ( 3), along with six known triterpenoids, were isolated from the roots of Camellia oleifera C. Abel. The structures of compounds 1- 3 were elucidated on the basis of spectroscopic analyses. Moreover, all compounds isolated were evaluated for their cytotoxic activities by MTT (=3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2 H-tetrazolium bromide) assay. [ABSTRACT FROM AUTHOR]

In a large-scale wireless sensor network, a topology is needed to gather state-based data from sensor network and efficiently aggregate the data given the requirements of balanced load, minimal energy consumption, and prolonged network lifetime. In this study, we proposed a ring-based hierarchical clustering scheme (RHC) consisting of four phases: predeployment, parent-child relationship building, deployment, and member join phases. Two node types are distributed throughout the network: cluster head nodes (type 1 node) and general sensor nodes (type 2 node). The type 1 node has better battery life, software capability, and hardware features than the type 2 node; therefore, the type 1 node is a better cluster head than type 2 node. Due to our IP naming rules and type 1 nodes as cluster heads, public key cryptography, such as RSA (Rivest, Shamir, Adleman), or ECC (Elliptic Curve Cryptosystem), is easily implanted to our system to strengthen our security. The sink node is the only certification authority in our system, but n level cluster heads can be extended to n level certification authorities if needed, where n is maximum number of level. [ABSTRACT FROM AUTHOR]

Maintaining viable populations in different habitats requires physiological, morphological and demographic adaptations of plants. In sandland environments, plants experience substantial variation in growing conditions during the dune fixation process, with high sand mobility in early stages and denser vegetation cover in later stages. We studied the changes in demography of a dominant shrub, Artemisia ordosica, at three stages of dune fixation: semi-fixed dunes, fixed dunes and fixed dunes covered with microbiotic crust. Demographic data from three annual censuses were used to parameterize integral projection models (IPMs) to conduct comparative demographic analyses. Plant growth and reproduction decreased strongly as dunes became more fixed. Shrinkage in plant height occurred very frequently, particularly in the fixed dunes with microbiotic crust. Population growth rate ( λ) declined substantially with dune fixation: from rapid expansion in semi-fixed dunes ( λ = 1.35-1.09) to moderate decline in fixed dunes with microbiotic crust ( λ = 0.94-0.89). Elasticity analysis revealed that survival was a key vital rate for population growth in all habitats. Growth and fecundity were of higher importance in the semi-fixed habitat than in the other two habitats where shrinkage became an important factor determining λ. Seedlings and small plants were critical for population growth in semi-fixed dunes, whereas moderate to large-sized plants were most important in the other habitats. Results of life table response experiments showed that the observed strong decrease in λ during dune fixation was mainly caused by reduction in fecundity, but with additional and considerable contributions from reduced plant growth and increased occurrence of shrinkage. Thus, populations in semi-fixed dunes are able to expand rapidly due to a much higher fecundity compared to those in other habitats. Synthesis. Artemisia ordosica adopts different life history strategies along the dune fixation process. Fast expansion in semi-fixed dunes is enabled by high seed production and effective recruitment, while populations at later dune fixation stages are maintained through frequent plant shrinkage. Integral projection models are highly appropriate tools for analysing such life history changes as they are based on statistical comparisons of vital rates across habitats. [ABSTRACT FROM AUTHOR]

Background: This study was to compare the effect of intensive insulin therapy (IIT) to conventional insulin therapy (CIT) on postoperative outcomes among type 2 diabetes mellitus (DM) patients who underwent D2 gastrectomy for gastric cancer. Methods: We randomly assigned gastric cancer patients with type 2 DM who underwent radical gastrectomy to receive IIT (maintenance of blood glucose at a level between 4.4 and 6.1 mmol/l) with insulin infusion or CIT (maintenance of blood glucose at a level between 10 and 11.1 mmol/l) during the postoperative period. Results: Of the 179 eligible patients, 92 patients were assigned to receive IIT and 87 patients to receive CIT. Mean blood glucose concentrations were lower in the intensive group (IG) than in the conventional group (CG) (5.5 ± 0.8 vs. 9.9 ± 1.0 mmol/l, P < 0.001). Hypoglycemia occurred in 6 patients (6.5%) in the IG ( P = 0.029) versus in 1 patient (1.1%) in the CG. Hospital mortality did not differ significantly between two groups (4.3% vs. 5.7%, P = 0.742). However, IIT significantly reduced morbidity (from 18.4 to 7.6%, P = 0.031). Also, IIT shortened the days to suture removal, postoperative hospital stay, and postoperative duration of antibiotic use. The HOMA-IR score was lower at all time points in IG. Moreover, IIT increased the postoperative HLA-DR expression on monocytes on postoperative days 3 and 5. Conclusions: IIT significantly reduced short-term morbidity but not mortality among type 2 DM patients who underwent D2 gastrectomy for gastric cancer. Furthermore, a possible mechanism of suppression of the insulin resistance and improvement of HLA-DR expression may partially explain the benefits of IIT. [ABSTRACT FROM AUTHOR]

Plants in a dune environment have a high risk of being denudated by wind or buried by sand. We conducted a field experiment to assess growth and reproductive performance as well as biomass allocation of Artemisia ordosica after denudation and burial. Height growth decreased after denudation, but remained constant after burial; biomass was reduced by severe burial, but not by moderate ones. Vegetative growth measured by current-year generated vegetative branches declined with increasing severity of burial. Reproductive maturity was not affected by either denudation or burial, and reproduction decreased only after severe denudation. After denudation, biomass allocated to reproduction was greatly reduced, as shown by strongly reduced biomass allocation to fruits and whole reproductive branches, but that allocated to current-year vegetative growth was maintained. Biomass allocation to reproduction and vegetative growth remained rather stable after burial. Current-year reproductive-to-vegetative-biomass ratio was lower after denudation than after burial, indicating that vegetative growth was more favored by A. ordosica after denudation. These modifications are adaptive in the fluctuating environment of mobile sand dunes where denudation and burial frequently occur. [ABSTRACT FROM AUTHOR]

The article presents a study that prepared flexible conductive composites using liquid silicone rubber as a matrix and conductive carbon black (CCB) as a filler. The study investigated the surface conductivity as a function of CCB concentration, frequency in the range from direct current to 1 megahertz. It revealed the alternating current resistivity of the composites with low CCB concentration as frequency dependent.

To test the Pleistocene interglacial refugia hypothesis with a high‐elevation mammal, we studied the phylogeography of the mole‐shrew (Anourosorex yamashinai) using partial mitochondrial cytochrome b gene sequences (737 bases). This shrew is endemic to Taiwan. It is mainly distributed in the highlands from 1000 to 2500 m in elevation. We examined 103 specimens from 24 localities in three mountain ranges of Taiwan and found 36 haplotypes. These haplotypes separated into two major phylogroups (Northern and Southern) plus a minor phylogroup (Houhuan) of only one haplotype. This demonstrated strong association with geography. The formation of these three phylogroups may be the result of interglacial refugia during the middle Pleistocene. Distinct sublineages were not found within each major phylogroup, suggesting that the populations (phylogroups) explosively expanded from the interglacial refugia of ancestral founder haplotypes. The present distribution pattern of haplotypes suggests that Mount Houhuan is an effective refugium in central Taiwan. It was not possible to specify the refugia for the Northern and Southern phylogroups. [ABSTRACT FROM AUTHOR]

To test the Pleistocene interglacial refugia hypothesis with a high-elevation mammal, we studied the phylogeography of the mole-shrew ( Anourosorex yamashinai) using partial mitochondrial cytochrome b gene sequences (737 bases). This shrew is endemic to Taiwan. It is mainly distributed in the highlands from 1000 to 2500 m in elevation. We examined 103 specimens from 24 localities in three mountain ranges of Taiwan and found 36 haplotypes. These haplotypes separated into two major phylogroups (Northern and Southern) plus a minor phylogroup (Houhuan) of only one haplotype. This demonstrated strong association with geography. The formation of these three phylogroups may be the result of interglacial refugia during the middle Pleistocene. Distinct sublineages were not found within each major phylogroup, suggesting that the populations (phylogroups) explosively expanded from the interglacial refugia of ancestral founder haplotypes. The present distribution pattern of haplotypes suggests that Mount Houhuan is an effective refugium in central Taiwan. It was not possible to specify the refugia for the Northern and Southern phylogroups. [ABSTRACT FROM AUTHOR]

Summary. Transforming growth factor-β (TGF-β) is a multifunctional regulator of cell growth and differentiation, whose actions are highly cell type specific. To study the role of the TGF-β1 autocrine loop in regulating growth and myogenic differentiation in the human rhabdomyosarcoma cell line, RD, an attempt was made to establish a framework for the expression of several components of TGF-β1/Smad signalling pathway at the mRNA and protein levels by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis in RD cells compared with the normal myoblasts. Higher exogenous concentration of TGF-β1 was necessary to reach a growth-inhibition effect, whereas TGF-β1 downregulated the expression of myosin heavy-chain mRNA at lower concentrations than that was required for growth inhibition. Treatment with TGF-β1 significantly decreased the number of sarcomeric actin and myosin-expressing cells. In this study, we have shown that RD cells displayed higher expression of TβRI, TβRII, Smad2 and Smad4 at both the mRNA and protein levels than myoblasts. Smad3 and Smad7 mRNA were expressed at higher level in RD cells than in myoblasts. The staining patterns of TβR and Smads suggest that they may transduce different TGF-β1 signalling in RD cells than in myoblasts. TGF-β1 signalling induced a rapid relocation of Smad2 to the nucleus; in contrast, Smad4 remained localized to the cytoplasm unless it was coexpressed with Smad2. These studies suggest that signalling from the cell surface to the nucleus through Smad proteins is a required component of TGF-β1-induced cell response in RD cells. The RD cell line is a suitable model to study the TGF-β autocrine loop involved in growth and differentiation of RMS. [ABSTRACT FROM AUTHOR]