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The bHLH transcription factors play pivotal roles in plant growth and development, production of secondary metabolites and responses to various environmental stresses. Although the bHLH genes have been well studied in model plant species, a comprehensive investigation of the bHLH genes is required for tobacco with newly obtained high-quality genome. In the present study, a total of 309 NtbHLH genes were identified and can be divided into 23 subfamilies. The conserved amino acids which are essential for their function were predicted for the NtbHLH proteins. Moreover, the NtbHLH genes were conserved during evolution through analyzing the gene structures and conserved motifs. A total of 265 NtbHLH genes were localized in the 24 tobacco chromosomes while the remained 44 NtbHLH genes were mapped to the scaffolds due to the complexity of tobacco genome. Moreover, transcripts of NtbHLH genes were obviously tissue-specific expressed from the gene-chip data from 23 tobacco tissues, and expressions of 20 random selected NtbHLH genes were further confirmed by quantitative real-time PCR, indicating their potential functions in the plant growth and development. Importantly, overexpressed NtbHLH86 gene confers improve drought tolerance in tobacco indicating that it might be involved in the regulation of drought stress. Therefore, our findings here provide a valuable information on the characterization of NtbHLH genes and further investigation of their functions in tobacco.

To study the evolution of pore structure in red clay during triaxial shear, nuclear magnetic resonance tests were performed on soil samples to determine their pore characteristics after undergoing different shear strains during triaxial consolidated undrained shear tests under different confining pressures. The results showed that the effects of confining pressure and shear on the intragranular pores of the soil samples were minimal. In contrast, during consolidation and triaxial shear, interparticle macropores in the soil sample were compressed. Generally, the greater the confining pressure during the test, the faster the soil structure stabilized. Once the axial strain exceeded 8%, the soil structure also stabilized, and both deviatoric stress and pore diameter remained unchanged. Evolution of the pore characteristics during triaxial shear revealed that their shear deformation history determined the new microstructure of the saturated compacted red clay.

Dimethyl carbonate (DMC) is well known as an extremely industrially valuable substance. The demand for high-efficiency synthesis of DMC has greatly driven the exploration of novel catalysts and their low-cost preparation methods. Herein, a novel method for the rapid batch preparation of CaO/carbon catalysts using calcium citrate (CaCi) was provided, and these catalysts were used to catalyze the transesterification reaction of methanol and ethylene carbonate (EC) to synthesize DMC and ethylene glycol (EG). Accordingly, the structure and properties of the catalysts were characterized using XRD, FTIR, N2 adsorption–desorption, TG, TG-IR, CO2-TPD, XPS, SEM, TEM and ICP-OES techniques. Meanwhile, the effect of various process conditions such as carbonization temperature, reaction temperature, reaction time and catalyst amount has been extensively evaluated. Under the optimal process parameters, the conversion of EC and the selectivity of DMC and EG were 81.2, 99.3 and 99.5%, while the turnover number (TON) and turnover frequency (TOF) were 54.1 and 162 h−1, respectively. Furthermore, kinetic analysis was carried out, and the value of k (reaction rate constant) was ≈0.159 mol L−1 min−1. The reusability was also investigated.

Adeno-associated viral vector-mediated transfer of DNA coding for broadly neutralizing anti-HIV antibodies (bnAbs) offers an alternative to attempting to induce protection by vaccination or by repeated infusions of bnAbs. In this study, we administered a recombinant bicistronic adeno-associated virus (AAV8) vector coding for both the light and heavy chains of the potent broadly neutralizing HIV-1 antibody VRC07 (AAV8-VRC07) to eight adults living with HIV. All participants remained on effective anti-retroviral therapy (viral load (VL) 1 μg ml(−1) in three individuals. In four individuals, VRC07 serum concentrations remained stable near maximal concentration for up to 3 years of follow-up. In exploratory analyses, neutralizing activity of in vivo produced VRC07 was similar to that of in vitro produced VRC07. Three of eight participants showed a non-idiotypic anti-drug antibody (ADA) response directed against the Fab portion of VRC07. This ADA response appeared to decrease the production of serum VRC07 in two of these three participants. These data represent a proof of concept that adeno-associated viral vectors can durably produce biologically active, difficult-to-induce bnAbs in vivo, which could add valuable new tools to the fight against infectious diseases.

This research conducted a triaxial test on lime-treated clay with different contents to analyze the effect of mechanical properties. Scanning electron microscope (SEM) and low-field nuclear magnetic resonance (NMR) analysis were used to analyze the effect. X-ray diffraction (XRD) was used to analyze the chemical changes of calcium oxide on red clay. The results show that with the increase of calcium oxide content, the strength increases, and it can be increased by 282% at 200 kPa confining pressure. The calcium oxide in the red clay reacted with the water in the soil to form calcium hydroxide. The alkaline environment will erode the edge of the soil particles and cause pores to become larger. SEM observed that the addition of calcium oxide caused the agglomeration of soil particles and changed the pore structure of red clay. Low-field NMR showed that calcium oxide had a significant effect on the pore structure of red clay. Calcium oxide increased the total pore volume of the soil sample. Calcium oxide had a substantial influence on the three pore distribution ranges, I (1.1–11 µm), II (15–137 µm), and III (137–512 µm). The porosity fitted with shear strength, it negatively correlated with I and III, and positively correlated with II.

The influence of precipitated calcium carbonate on the strength and microstructure of red clay was studied. Precipitated calcium carbonate was added to red clay at ratios of 0%, 5%, 10%, 15%, and 20%. Shear tests were carried out on the samples to observe the effect of calcium carbonate on the mechanical properties of red clay. The results showed that, with increasing calcium carbonate content, the strength of red clay first decreased and then increased. The maximum strength was obtained for the sample with 20% calcium carbonate. Scanning electron microscopy (SEM) was used to observe the changes in microstructure caused by addition of calcium carbonate. The pores and cracks analysis system (PCAS) was used to quantitatively characterize the microstructure changes detected in SEM images. The addition of calcium carbonate decreased the pore area and increased the total number of pores of red clay. The incorporation of calcium carbonate caused the red clay particles to agglomerate. The higher the calcium carbonate content, the stronger the agglomeration of red clay particles in the soil samples.

Cytoplasmic male sterile (CMS) lines are valuable resources in plant breeding for heterosis utilization, guaranteeing quality of hybrid seeds, and genetic integrity. Nta(sua)S K326, which contains the nuclei of Nicotiana tabacum cv. K326 and cytoplasm of N. suaveolens, is currently the dominant CMS source used in tobacco leaf production in Yunnan, China. Therefore, the alternative CMS lines are required. Here, the Nta(gla)S K326 with cytoplasm of N. glauca has been generated from asymmetric somatic hybridization between protoplasts of K326 and N. glauca followed by backcrossing with K326. Flow cytometry analysis revealed that Nta(gla)S has almost identical ploidy level as that in K326. Moreover, Nta(gla)S, Nta(sua)S, and K326 plants showed similar relative growth rate, yield, and contents of several chemical components in the field. Further scaning electron microscopic observation of floral organs revealed that the Nta(gla)S has shortened filaments and shrivelled stamens, whereas the Nta(sua)S has severe degenerated and carpel-liked stamens, compared with fertile K326 plants. In addition, the expression patterns of several mitochondrial genes in Nta(gla)S, Nta(sua)S, and K326 plants were compared. Furthermore, the cytoplasm source of Nta(gla)S and Nta(sua)S could be distinguished by cleaved amplified polymorphic sequence (CAPS) analysis with chloroplast-specific universal primers. Taken together, these results showed the development of a Nicotiana CMS hybrid via asymmetric somatic hybridization, suggesting that flow cytometry analysis at early stage could facilitate and accelerate the selection process of generating CMS lines. Importantly, the Nta(gla)S provides a valuable germplasm as an alternative CMS line instead of Nta(sua)S in Nicotiana hybrid breeding. The Nicotiana CMS hybrid Nta(gla)S has been generated by asymmetric protoplast hybridization. The Nta(gla)S provides a valuable germplasm as an alternative CMS line instead of Nta(sua)S in Nicotiana hybrid breeding.

Engineering practice and real-life cases show that the geological conditions of the Guilin overlying karst site are complex. In particular, the groundwater, which drives the accelerated formation of soil cavities, and the thickness of the overlying soil layer, which affects the speed of the groundwater subsidence process. Therefore, this paper is based on a physical model to evaluate the effects of groundwater level changes caused by different factors on the deformation of karst cover. The model tests are simulated for different cover thicknesses (6 cm, 9 cm, 12 cm, 15 cm, 18 cm) under rainfall and other recharge, cavity supply, and drainage conditions at the same density (1.40 g/cm3) and initial water content (30%), respectively. The results show that with the increase of rainfall and other recharge time, the basic change trend of different cover thicknesses is that the infiltration curve changes faster at the beginning and slows down at the end, but the thicker the cover, the slower the overall deformation; at a certain rate of cavity recharge and drainage, the thicker the cover, the smaller the deformation caused by the fluctuation of groundwater level. The cavity recharge makes the cover displacement obvious, in the order of 0.304 cm, 0.173 cm, 0.118 cm, 0.068 cm, and 0.056 cm. After the formation of the cavity, the rainfall, other recharge, and the cavity supply and drainage accelerate the destruction and deformation of the soil body and the upward development of the cavity. The research results provide theoretical support for the subsequent prevention and control of karst collapse in covered karst areas, and have certain practical engineering significance.

Flowering time is an important agronomic trait that contributes to fitness in plants. However, the genetic basis of flowering time has not been extensively studied in pepper. To understand the genetics underlying flowering time, we constructed an F2 population by crossing a spontaneous early flowering mutant and a late-flowering pepper line. Using bulked segregant RNA-seq, a major locus controlling flowering time in this population was mapped to the end of chromosome 2. An APETALA2 (AP2) homolog (CaFFN) cosegregated with flowering time in 297 individuals of the F2 population. A comparison between the parents revealed a naturally occurring rare SNP (SNP2T > C) that resulted in the loss of a start codon in CaFFN in the early flowering mutant. Transgenic Nicotiana benthamiana plants with high CaFFN expression exhibited a delay in flowering time and floral patterning defects. On the other hand, pepper plants with CaFFN silencing flowered early. Therefore, the CaFFN gene acts as a flowering repressor in pepper. CaFFN may function as a transcriptional activator to activate the expression of CaAGL15 and miR156e and as a transcriptional repressor to repress the expression of CaAG, CaAP1, CaSEP3, CaSOC1, and miR172b based on a qRT-PCR assay. Direct activation of CaAGL15 by CaFFN was detected using yeast one-hybrid and dual-luciferase reporter assays, consistent with the hypothesis that CaFFN regulates flowering time. Moreover, the CaFFN gene association analysis revealed a significant association with flowering time in a natural pepper population, indicating that the CaFFN gene has a broad effect on flowering time in pepper. Finally, the phylogeny, evolutionary expansion and expression patterns of CaFFN/AP2 homologs were analyzed to provide valuable insight into CaFFN. This study increases our understanding of the involvement of CaFFN in controlling flowering time in pepper, thus making CaFFN a target gene for breeding early maturing pepper.

Most people are dwelling in cities, which contain a high density of buildings constructed of concrete or similar materials. Conventional grey-colored concrete is absorptive to solar radiation and discharges the absorbed heat to the air as sensible heat, contributing to the development of urban heat island. While existing studies have attempted to find high-reflective concrete by varying the components of the concrete mix, the influence of cured conditions on the albedo of concrete samples is still unknown and has not been reported. Here we first prepared 120 cement pastes with different water-to-cement ratios and different cementitious materials, and then cured the pastes in an indoor environment and a moist chamber, respectively. After cured in a moist chamber for 28 days and then cured in the air for 365 days, the spectral reflectance of all the pastes was tested. Experimental results indicated that the pastes cured in a moist chamber have an albedo that is 0.01–0.10 greater than those of the pastes cured in an indoor environment, with a greater albedo difference at relatively higher water-to-cement ratios. The results also revealed that when concrete productions, such as concrete roof tiles and concrete paver blocks, are prepared, it is practical to cure such productions in a moist environment to get a high albedo.

Background Abscisic acid (ABA) is an important phytohormone for plant growth, development and responding to stresses such as drought, salinity, and pathogen infection. Pyrabactin Resistance 1 (PYR1)/PYR1-Like (PYL)/Regulatory Component of ABA Receptor (RCAR) (hereafter referred to as PYLs) has been identified as the ABA receptors. The PYL family members have been well studied in many plants. However, the members of PYL family have not been systematically identified at genome level in cultivated tobacco (Nicotiana tabacum) and its two ancestors. In this study, the phylogenic relationships, chromosomal distribution, gene structures, conserved motifs/regions, and expression profiles of NtPYLs were analyzed. Results We identified 29, 11, 16 PYLs in the genomes of allotetraploid N. tabacum, and its two diploid ancestors N. tomentosiformis and N. sylvestris, respectively. The phylogenetic analysis revealed that NtPYLs can be divided into three subfamilies, and each NtPYL has one counterpart in N. sylvestris or N. tomentosiformis. Based on microarray analysis of NtPYL transcripts, four NtPYLs (from subfamily II, III), and five NtPYLs (from subfamily I) are highlighted as potential candidates for further functional characterization in N. tabacum seed development, response to ABA, and germination, and resistance to abiotic stresses, respectively. Interestingly, the expression profiles of members in the same NtPYL subfamily showed somehow similar patterns in tissues at different developmental stages and in leaves of seedlings under drought stress, suggesting particular NtPYLs might have multiple functions in both plant development and drought stress response. Conclusions NtPYLs are highlighted for important functions in seed development, germination and response to ABA, and particular in drought tolerance. This work will not only shed light on the PYL family in tobacco, but also provides some valuable information for functional characterization of ABA receptors in N. tabacum. Electronic supplementary material The online version of this article (10.1186/s12864-019-5839-2) contains supplementary material, which is available to authorized users.

The construction of roadways in permafrost regions modifies ground-surface conditions and consequently, negatively varies thermal stability of the underlying frozen soils. To avoid the thawing of the permafrost layer under the scenario of global warming, roadways are usually laid on a built-up embankment, which not only disperses the traffic loads to underlying layers but also minimize the thermal disturbance. In the embankment, duct ventilation, or called air duct, can be embedded to further cool the underlying permafrost. While the thermal performance of duct ventilations has been well documented, the long-term structural stability of duct ventilation remains unknown. This study examines the structural stress of ventilation ducts that are placed in harsh weather such as the Qinghai-Tibet Plateau. The ducts are currently buried in the embankment filler, with the wind-outlet and -inlet ends exposed and cantilevered out of the embankment. Field studies found that the exposed parts have plagued cracking and even failures, especially at the fixed end of the cantilevered part. Damages of these concrete ducts are attributed to cyclic freezing-thawing attack, thermally-induced stresses, moisture-induced stresses, and concrete swelling. These physical attacks are caused by the harsh weather in the Qinghai-Tibet plateau. It is recommended to insulate the exposed part of the ducts and to fabricate durable and dense concrete ducts.

Being an essential mineral nutrient, potassium (K+) plays numerous important roles in plant growth and development and determines the yield and quality of crop products. The cellular level of K+ is controlled to a large extent by the K+ transporter, which belongs to the KT/HAK/KUP (HAK) family. However, little is known about these genes in tobacco. In this study, we surveyed the tobacco genome and identified 41 putative NtHAK genes (NtHAKS1–NtHAKS21 and NtHAKT1–NtHAKT20). Investigation of the cis-elements in upstream regions of these NtHAK genes suggests that members of this family respond to environmental cues and phytohormones. Expression data mining reveals that NtHAK genes showed clear sub-genome dominance. In all, these results will provide molecular insights into K+ transporter research in tobacco.

Objective: To assess the clinical effects of emergency gastroscopies on acute upper gastrointestinal hemorrhage patients. Methods: 212 patients with acute upper gastrointestinal hemorrhages were randomly divided into an experimental group (n=106) and a control group (n=106). The experimental group underwent emergency gastroscopies, and the control group underwent the traditional treatment. We measured the hemostasis effects, the treatment indexes, and the incidences of adverse reactions to assess the clinical effects. At the same time, we recorded the hemoglobin levels, the rebleeding rates, and the mortality rate to assess the hemostasis effect. Results: The hemostasis effect (the total hemostasis effective rate), the treatment index (the hemostasis time, stool occult blood turning negative time, bowel sound recovery time, and the blood transfusion volumes), the hemoglobin levels, the rebleeding rates, and the mortality were better in the EG than they were in the CG (P

In order to study the permeability characteristics of heavy metal ions contaminated red clay and explore the rapid detection of permeability of heavy metal contaminated red clay. Through variable-head permeability test and electrical resistivity test (different voltages and methods), the effects of Cu2+ concentration and initial water content on hydraulic conductivity characteristic and resistivity of contaminated red clay was systematically investigated. The relationship between permeability characteristic and electrical resistivity was further explored by taking Cu2+ concentration and moisture content as the intermediate variable. The obtained results indicate that the different voltage has no obvious effect on the resistivity of the samples. The four-phase electrode method is more accurate than the two-phase electrode method. With increasing Cu2+ concentrations the hydraulic conductivity of specimens increases, however the permeability coefficient of contaminated soil decreases with increasing initial water content. In the resistivity test, with increasing of Cu2+ concentrations and water content, the resistivity of samples presented a downward trend, which is decreased sharply at first and then tended to be gentle. The relationship between hydraulic conductivity and resistivity of contaminated soil showed a good fitting curve no matter in different Cu2+ concentration or in different water content, but the fitting curves of them presented opposite trend.

Additional file 1: Table S1. All primer sequences used in experiments. Table S2. Information for all antibodies used in experiments. Table S3. Hh signaling pathway related genes

To study the effects of different concentrations of zinc ions on the mechanical strength, material composition, and microstructure of red clay, a triaxial test, an x-ray diffraction test, an x-ray fluorescence spectrometry test, a scanning electron microscopy test, and a mercury intrusion test were carried out on contaminated soil to investigate the mechanisms of zinc ion-contaminated red clay. The results show that the higher the concentration of zinc ions, the smaller the shear strength and cohesion of the red clay. The internal friction angle is increased first and then decreased. From material composition, zinc ion makes montmorillonite and hemite disappear in red clay. With the increase of zinc ion concentration, quartz semiquantitative increase and kaolinite semiquantitative decrease and the content of SiO2, Fe2O3, and Na2O reduces. Microscopically, the structure of red clay changes from floc structure to granular and aggregate structure after the zinc ions are added, while the contact of the particles is converted to point contact. With the increase of the concentration of zinc ions, the porosity and the fractal dimension of the red clay gradually increase, and the stability of the granular structure is weakened.

Backcrossing is a powerful tool for plant breeding. The improved marker-assisted backcrossing intends to transfer targeted genes or quantitative trait loci (QTLs) of interest from a donor parent into a recurrent parent. In this study, a tobacco BC4F3 population was generated using Y3 and K326 as hybrid parents and YF1-1 as F1 parents. High-throughput sequencing data of 381 pedigree populations were used to construct high-density genetic maps containing 24 142 high-quality single nucleotide polymorphism (SNP) markers with an average genetic distance of 0.59 cM. A genome module analysis was then performed for all the offspring. A total of forty-three candidate QTLs for six agronomics traits were identified. This study provides original biomarkers for tobacco breeding and offers clues for prospective backcrossing applications in other plants.

Tobacco (Nicotiana tabacum L.) is an economic crop and a model organism for studies of plant biology and genetics. As an allotetraploid plant generated from interspecific hybridization, tobacco has a massive genome (4.5 Gb). Recently, a genetic map with 45,081 single nucleotide polymorphism (SNP) markers was constructed using whole-genome sequencing data for a tobacco population including 274 individuals. This provides a basis for quantitative trait locus (QTL) mapping and genomic selection, which have been widely applied to other crops but have not been feasible in tobacco. Based on this high-density genetic map, we identified QTLs associated with important agronomic traits, chemical compounds in dry leaves, and hazardous substances in processed cigarettes. The LOD values for major QTLs were highest for agronomic traits, followed by chemical compounds and hazardous substances. In addition to the identification of molecular markers, we evaluated genomic selection models and found that BayesB had the highest prediction accuracy for the recombinant inbred line population. Our results offer new insights into the genetic mechanism underlying important traits, such as agronomic traits and quality-related chemical compounds in tobacco, and will be able to support the application of molecular breeding to tobacco.

Immune checkpoint inhibitor (ICI) treatments produce clinical benefit in many patients. However, better pretreatment predictive biomarkers for ICI are still needed to help match individual patients to the treatment most likely to be of benefit. Existing gene expression profiling (GEP)-based biomarkers for ICI are primarily focused on measuring a T cell-inflamed tumour microenvironment that contributes positively to the response to ICI. Here, we identified an immunosuppression signature (IMS) through analysing RNA sequencing data from a combined discovery cohort (n = 120) consisting of three publicly available melanoma datasets. Using the ratio of an established IFN-γ signature and IMS led to consistently better prediction of the ICI therapy outcome compared to a collection of nine published GEP signatures from the literature on a newly generated internal validation cohort (n = 55) and three published datasets of metastatic melanoma treated with anti-PD-1 (n = 48) and anti-CTLA-4 (n = 42) as well as in patients with gastric cancer treated with antiPD-1 (n = 45), demonstrating the potential utility of IMS as a predictive/prognostic biomarker that complements existing GEP signatures for immunotherapy.

Objective. This study aimed to compare the effectiveness of drug-coated balloons (DCB) with everolimus-eluting stents (EES) in the treatment of in-stent restenosis (ISR) and the differential relative effect of DCB in patients with drug-eluting stents (DES)-ISR and bare metal stents (BMS)-ISR. Background. The efficiency and safety of DCB and EES need to be assessed for the treatment of ISR. Methods. A systematic literature search was conducted using PubMed and EMBASE to identify all relevant studies. Angiographic results and clinical events were separately assessed. Subgroup meta-analyses were performed according to the type of restenosed stent. Results. Six randomized trials with 1134 patients were included. The overall pooled outcomes indicated that DCB was associated with lower minimum lumen diameter (mean difference MD=−0.17, 95% CI = −0.29 to −0.05, P=0.006) and higher target lesion revascularization (risk ratio RR=2.38, 95% CI = 1.36 to 4.18, P=0.002) than EES. However, the subgroup meta-analyses showed that DCB was inferior to EES only in DES-ISR patients, with lower minimum lumen diameter (MD=−0.25, 95% CI = −0.37 to −0.14, P

The aim of this study was to investigate genetic diversity of flue-cured tobacco (Nicotiana tabacum L.) germplasm and to screen molecular markers for agronomic and chemical traits. A total of 231 flue-cured tobacco germplasms were genotyped with 120 simple sequence repeats (SSRs) markers uniformly distributed on 24 linkage groups. Associations of SSR variation with eight agronomic traits and five chemical components were investigated by two contrasting statistical models, i.e. general linear model (GLM) and mixed linear model (MLM). Overall, 403 alleles were identified in all accessions, ranging from 2 to 21 per locus, with an average of 3.36 alleles per locus. Mean polymorphic information content was 0.408, ranging from 0.036 to 0.785. Genetic distance between varieties ranged from 0.003 to 0.371, with a mean of 0.148. Using unweighted pair-group method with arithmetic mean (UPGMA), all accessions were clustered into four groups at a genetic distance of 0.153. Using population genetic structure analysis, the test materials were divided into three subpopulations. Association analysis by GLM_Q and MLM_Q+K models revealed that seventeen and nine markers were significantly associated with a total of 13 phenotypic traits, respectively. Moreover, nine markers were consistently associated with the same traits at the p < 0.001 level in two years using both models. Specifically, three markers associated with plant height (TM10481, PT54964, and TM20580), two markers with leaf number (TM10846 and PT60728), one marker with stem circumference (TM25276), and one marker with leaf length (TM11215) supported published quantitative trait locus (QTL) mapping results. These seven markers could be used in future molecular marker-assisted selection to improve breeding efficiency.

MADS-box genes play a pivotal role in various processes, including floral and seed development, controlling flowering time, regulation of fruits ripening, and respond to abiotic and biotic stressors in planta. Tobacco (Nicotiana tabacum) has been widely used as a model plant for analyzing the gene function, however, there has been less information on the regulation of flowering, and the associated genes. In the present study, a total of 168 NtMADS-box genes were identified from tobacco, and their phylogenetic relationship, chromosome locations, and gene structures were further analyzed. NtMADS-box genes can be clustered into four sub-families of M&alpha, M&gamma, MIKC*, and MIKCC. A total of 111 NtMADS-box genes were distributed on 20 chromosomes, and 57 NtMADS-box genes were located on the unanchored scaffolds due to the complex and incomplete assembly of the tobacco genome. Expression profiles of NtMADS-box genes by microarray from 23 different tissues indicated that members in different NtMADS-box gene subfamilies might play specific roles in the growth and flower development, and the transcript levels of 24 NtMADS-box genes were confirmed by quantitative real-time PCR. Importantly, overexpressed NtSOC1/NtMADS133 could promote early flowering and dwarfism in transgenic tobacco plants. Therefore, our findings provide insights on the characterization of NtMADS-box genes to further study their functions in plant development.

Leaf chemistry traits are some of the key factors influencing tobacco quality, which can be significantly reduced by lower chemical components in cured leaf. To improve tobacco quality through breeding, genetic diversity analysis, population structure analysis, and genome-wide association studies were performed in a panel of 347 tobacco germplasms and the markers associated with five leaf chemistry traits, including total sugar (TS), reducing sugar (RS), total nitrogen (TN), nicotine (NIC), and total potassium (TP) contents were identified. Four groups were classified at a genetic distance of 0.316 by genetic diversity analysis based on coefficient parameter NEI72 using a program NTSYS-pc2.10e, whereas four well-differentiated subpopulations were postulated in the 347 tobacco accessions. A total of 47 target trait-associated SNPs was detected in at least three environments as well as the best linear unbiased predictions (BLUPs) across all environments, among which two, two, four, six, and one highly suggestive associated SNPs were repeatedly detected in all environments and BLUPs for TS, RS, TN, NIC, and TP, respectively. On the basis of the phenotypic effects of the alleles corresponding to suggestive associated SNPs, five tobacco accessions harboring favorable alleles with elite phenotypic performance in leaf chemistry traits were identified. The results could facilitate quality tobacco breeding for higher leaf chemistry trait contents through molecular marker-assisted approaches.

Tobacco (Nicotiana tabacum L.) is an essential commercial crop and an ideal model plant for biological mechanism studies. As an allopolyploid species, tobacco harbors a massive and complex genome, which makes the application of molecular markers complicated and challenging. In our study, we performed whole-genome sequencing of an intraspecific recombinant inbred line (RIL) population, a F1 generation and their parents. With the Nicotiana tabacum (K326 cultivar) genome as reference, a total of 45,081 markers were characterized to construct the genetic map, which spanned a genetic distance of 3486.78 cM. Evaluation of a two-dimensional heat map proved the high quality of the genetic map. We utilized these markers to anchor scaffolds and analyzed the ancestral genome origin of linkage groups (LGs). Furthermore, such a high-density genetic map will be applied for quantitative trait locus (QTL) detection, gene localization, genome-wide association studies (GWAS), and marker-assisted breeding in tobacco.

Buildings in Southern China widely use a double-skin roof to reduce heat entry through the roof to the building interior during summertime. Concrete roof tiles are preferably installed as the outmost layer of the double-skin roof due to their resistance to hail and wind damages and their attractive price. However, after construction, the tile’s top tends to be darkened by dust deposit and algae growth, increasing the heat entry through the roof to the building. Here, we show that this heat entry can be curtailed by lowering the emissivity at the tile’s underside. Temperatures and heat fluxes at different elevations of a double-skin roof with concrete tiles as the outmost layer of the roof are monitored. The underside of each concrete tile is coated with a specific paint to get a unique emissivity. Observations reveal that lowering the emissivity of concrete roof tiles could cut down the summer heat gain of buildings in tropical regions.

The calcium carbonates of different particle sizes were incorporated into red clay, and the consolidated undrained triaxial test on red clay was performed by the TKA-TTS-1 triaxial apparatus to analyze the effects of different particle sizes of calcium carbonate and the different incorporation rates of calcium carbonate on the mechanical properties of red clay. The results show that the incorporation of calcium carbonate reacts with the cement formed by free ferric oxide in red clay, resulting in a decrease in cohesion and changing the strength of red clay. With the increase of nano-calcium carbonate incorporation rate, the shear strength of red clay decreased, and it showed a trend of decreasing first and then increasing. Because the specific surface area of nano-calcium carbonate is larger than that of ordinary calcium carbonate, it has a significant effect on the mechanical properties of red clay.

Direct shear tests were performed on red clay soaked in different concentrations of sodium hydroxide solution and different soaking time. The microstructure of red clay samples was observed by scanning electron microscopy (SEM). The results show that the shear strength of red clay soaked in sodium hydroxide solution decreases as the soaking time and the sodium hydroxide solution concentration increases. The sodium hydroxide solution eroded the cement in the red clay, resulting in the increase of pores between clay particles. The fractal dimension of the red clay particles increased with the increase of the corrosion. The average particle size and average particle area of the red clay particles decrease with the increase of the sodium hydroxide corrosion, and the shape of the soil particles becomes irregular.

Black shank, caused by Phytophthora nicotianae (P. nicotianae), is a serious disease of cultivated tobacco (Nicotiana tabacum) worldwide. The interactions between tobacco and P. nicotianae are complex and the outcomes of the interactions depend on the tobacco genotype, P. nicotianae strain, and environmental conditions. In this study, we used RNA-sequencing (RNA-Seq) to investigate and compare transcriptional changes in the stems of tobacco upon inoculation with P. nicotianae strain race 0. We used two tobacco varieties: RBST (named from resistance to black shank and tobacco mosaic virus), which was resistant to the P. nicotianae strain race 0, and Honghuadajinyuan (HD), which was susceptible to P. nicotianae race 0. Samples were collected 12 and 72-hour post inoculation (hpi). Analysis of differentially expressed genes (DEGs) and significantly enriched GO terms indicated that several basic defense mechanisms were suppressed in both varieties, which included response to wounding (GO: 0009611), and defense response to fungus (GO: 0050832). We also found some genes that may especially be related to mechanisms of resistance in RBST, such as the one encoding a chitinase. These results will provide a valuable resource for understanding the interactions between P. nicotianae and tobacco plants.

In order to optimize maize production and variety utilization in high altitude areas, the growth period and some quality traits of three maize varieties were compared among five elevations, 1280.0, 1506.5, 1706.5, and 2000.0, 2231.5 m in Gansu province and three elevations, 1435.0, 1860.0, and 2186.0 m in Yunnan province, China. This vertical ecological experiment was conducted in 2008 and 2009. The results showed that the growth period of maize sowed at similar time was extended along with altitude elevating, there was about 4–5 d extension with each 100 m increase in altitude. Both fat content and amylose/starch ratios had significant negative correlations with altitude, no correlation was found between crude protein content and altitude.

Background Leukemia is the second most malignant tumor in children. The chemotherapy induced anemia (CIA) and hemorrhage are the most popular side-effects due to the myelosuppression of chemotherapy. So far, multitransfusion is still the timely and effective measure in curing these complications. The acquisition of HIV infection and subsequent development of AIDS by component transfusion from donors at risk is well known, and prognosis of HIV infection is particularly severe in patients with leukemia. Case Presentation We report two leukemic cases that were infected with HIV through transfusion. The first patient was totally transfused with 16 U RBC, 20 U platelets and 820 ml fresh frozen plasma, and later test showed that his first used FFP carried the HIV. For the second 2 U RBC, 5 U platelets and 1500 ml fresh frozen plasma were transfused to her. Late test of her used blood products showed that the fourth RBC carried the HIV. Both results were confirmed by the local Center for Disease Control (CDC). They were not transfused before the diagnosis of leukemia. Their parents were healthy with negative HIV-Ab. Conclusion Since the two leukemic patients suffered transfusion-associated HIV with poor prognosis, we must take more efforts to utilize blood products judiciously, manage blood donors, test blood samples etiologically, shorten HIV testing "window periods" and develop preventive vaccination against HIV to reduce the incidence as low as possible.

Slim-loop ferroelectric ceramics of Pb(Zr,Sn,Ti)O 3 were prepared by partial replacing Pb with Ba and La, and replacing Zr, Sn, and Ti with Nb. The saturation polarization (P s ) and remnant polarization (P r ) were measured to be 20.66 μ C/cm 2 and 0.55 μ C/cm 2 , respectively. A relative permittivity e ≈ 2840 can be reached in these ferroelectric ceramics at room temperature and frequency of 1kHz. The discharge energy density (w) increases in a nearly linearity with the voltage. A discharge energy density of about 0.410J/cm 3 can be obtained at the electrical field of 6000 V/mm. Pulse charge-discharge measurements were conducted and the releasing charges Q retained 80% after 1000 cycles. These ferroelectric ceramics have potential for pulse power capacitor applications.

Tobacco (Nicotiana tabacum L.), particularly flue-cured tobacco, is one of the most economically important nonfood crops and is also an important model system in plant biotechnology. Despite its importance, only limited molecular marker resources are available for genome analysis, genetic mapping, and breeding. Simple sequence repeats (SSR) are one of the most widely-used molecular markers, having significant advantages including that they are generally co-dominant, easy to use, abundant in eukaryotic organisms, and produce highly reproducible results. In this study, based on the genome sequence data of flue-cured tobacco (K326), we developed a total of 13,645 mostly novel SSR markers, which were working in a set of eighteen tobacco varieties of four different types. A mapping population of 213 backcross (BC1) individuals, which were derived from an intra-type cross between two flue-cured tobacco varieties, Y3 and K326, was selected for mapping. Based on the newly developed SSR markers as well as published SSR markers, we constructed a genetic map consisting of 626 SSR loci distributed across 24 linkage groups and covering a total length of 1120.45 cM with an average distance of 1.79 cM between adjacent markers, which is the highest density map of flue-cured tobacco till date.

Ruxolitinib, an orally bioavailable JAK1/JAK2 inhibitor, may treat cancers with CRLF2 and/or JAK pathway mutations.A phase 1 trial of ruxolitinib was performed to determine the maximum tolerated or recommended phase 2 dose, dose-limiting toxicities (DLTs), pharmacokinetics (PK), and pharmacodynamics (PD) in children with recurrent/refractory solid tumors (STs). Ruxolitinib was administered twice daily (BID) in 28-day cycles at five dose levels (15, 21, 29, 39, and 50 mg/m(2)/dose). PK and PD studies were performed during cycle 1. Toxicity, preliminary efficacy, and PK/PD were also assessed in children with relapsed/refractory hematologic malignancies (HMs).Forty-nine patients were enrolled, 28 with STs (dose escalation cohort) and 21 with HMs. Ruxolitinib was well-tolerated with one DLT per cohort of six patients at dose levels (DLs) 2-5. One patient with an ST had grade 5 multi-organ failure at DL2. One patient each at DL3 and DL4 had a grade 4 neutropenia, and one patient at DL5 had a grade 4 creatinine phosphokinase elevation. No objective responses were observed in patients with STs. One patient with polycythemia vera achieved a partial response and received 18 cycles of ruxolitinib. The PK of ruxolitinib were similar to that in adults. Partial inhibition of phosphorylated JAK2, STAT5, and S6 was observed in in vitro plasma inhibitory activity PD assay.Ruxolitinib was well tolerated in children with refractory cancer. The recommended phase 2 dose for continuous BID oral administration is 50 mg/m(2)/dose. Subsequent evaluation of ruxolitinib in combination with cytotoxic chemotherapy in children, adolescents, and young adults with JAK-mutant leukemias is planned.

This study was designed to investigate the role of MCT1 in the development of cisplatin-resistant ovarian cancer and its possible relationship with Fas. We found the expression of MCT1 was obviously increased both in cisplatin-resistant ovarian cancer tissue and A2780/CP cells compared with sensitive ovarian cancer tissue and cell lines A2780. And in A2780 cells treated with Cisplatin, the expression of MCT1 increased in a concentration-dependent manner, MCT1 knockdown attenuates cisplatin-induced cell viability. In A2780 and A2780/CP cells transfected with MCT1 siRNA, the activation of several downstream targets of Fas, including FasL and FAP-1 were largely prevented, whereas the expression of Caspase-3 was increased, accompanying with increased abundance of Fas. Coimmunoprecipitation and immunofluorescence showed that there is interaction between endogenous MCT1 with Fas in vivo and in vitro. In vivo, depletion of MCT1 by shRNA reverses cisplatin-resistance and the expression of Fas. This study showed that down regulation of MCT1 promote the sensibility to Cisplatin in ovarian cancer cell line. And this effect appeared to be mediated via antagonizing the effect of Fas.

As water transporters, aquaporins (AQPs) are closely related to other membrane transporters, and water permeability in cell may contribute to chemosensitivity of tumor. To understand the correlation between AQPs and cisplatin (DDP) sensitivity to ovarian cancer cells, effects of DDP on AQPs expression were detected in vitro, and chemosensitivity of DDP was observed in hypertoncity in vitro.SKOV3 cells were incubated with DDP, aquaporins blocker mercuric chloride, or in hypertonicity, and cell proliferation inbihition was measured by MTT. Effects of DDP on AQPs mRNA expression cancer cell SKOV3 were measured by RT-PCR.MTT analyses showed that aquaporin blocker and hypertonicity increased the sensitivity of SKOV3 to DDP. The effects of DDP on AQPs expression were different between aquaporin subtypes: following an increase in the incubation time, the expression of AQP1 mRNA decreased significantly, but expression of AQP3 and AQP8 increased.Our studies have showed that different subtypes of AQPs play different roles in ovarian cancer cell in vitro, and which suggested that AQPs might be associated with chemotherapy sensitivity of ovarian cancer.

New calculations of the cross sections for antihydrogen formation in collisions of antiprotons with positronium are reported in the present paper. A multiple-scattering expansion method has been used for getting reliable results. Discussion and comparison of the present results are made with other theoretical calculations.

The binding energy spectra and the momentum distributions of the valence orbitals of iso-butane, also known as methylpropane (CH3CH(CH3)CH3), are studied by using a high resolution binary (e, 2e) electron momentum spectrometer, at an impact energy of 1200eV plus the binding energy (8-32eV) with symmetric non-coplanar kinematics. Binding energy spectra of the valence shell are obtained at a coincidence energy resolution of 0.95 eV in full width at half maximum. The experimental momentum profiles of the inner valence orbitals are obtained and compared with the theoretical momentum distributions calculated by using Hartree-Fock and density functional theory methods with the basis sets 6-31G and 6-311++G**. The pole strengths of the inner orbitals are estimated and the final correlation effects are discussed.

A systematic study was performed on the structural, magnetic and optical properties of polycrystalline I$\sb2$.Mn.IV.VI$\sb4$ compounds with I = Ag or Cu, IV = Si, Ge, Sn, VI = S, Se and Te. In X-ray diffractometry, three different crystal structures were observed, two corresponding to the tetragonal stannite and orthorhombic wurtz-stannite structures reported previously, and thirdly a cubic rock salt-like structure. Magnetic susceptibility ($\chi$) measurements showed that most of the selenide phases were ferrimagnetic. Optical absorption measurements were made to determine values of optical energy gap E$\sb{\rm o}$ for a number of the single phase samples. When the values of these various parameters ($\rm a\sb{e}, T\sb{N}, \theta\sb{a}$ and E$\sb{\rm o}$) were compared for the various phases, it was found that the phases could be classified into five different sets. In each case investigated, the variation of E$\sb{\rm o}$ with temperature was found to agree well with the theoretical predictions of Alexander et al. (76A1). (Abstract shortened by UMI.)

The paper provide a new algorithm for multiple radar time series similarity matcing. The main difficulty for multiple radar time series similarity matching lies in huge data amount and too many factors will be considered. So, the previous algorithm on this area has existance of false dismissals and false alarms. The traditional methods mostly based on Euclidean distance and pay little attention to the influence of amplitude change, frequency persistence and internal structure of sequence. The matching method held out in the paper firstly devided the radar spatial data into certatin segments based on its' spatial position. Then, the mutidemession time series in each data segments can maped to a time interval with certain length. The step can transform multiple radar time series to three-demession time series and greatly reduce the complexity of algorithm. In order to improve the accuracy of the method, some weighted factor with consideration of amplitude change, frequency persistence and internal structure of radar sequence is carried out to define an accuracy distance measure for two sequences. With the predefined distance measure, a multiple radar time series similarity measure modal and an algrothm for similarity matching is discussed in detail. At the end of the paper, the method in the paper is applied in actually radar observed data and proved its better performance.

The first extensive electron momentum spectroscopy study of the satellite structure in the inner valence region of methane at 1200 eV is reported. The experimental momentum profiles belonging to the (2a1)-1 satellite state are presented at energies 25.3, 28.5, 31.5, 35.5 eV, and compared with the 146-G(CI) calculation.

Accurate measurements of the binding energy spectrum and momentum distribution of argon are performed using the high resolution (ΔE = 1.4 eV, Δp = 0.1 a.u.) energy multichannel (e, 2e) spectrometer (θ1 = θ2 = 45°, = 0°-±30°) built recently in our laboratory. Detailed satellite structure of argon has been observed. Good agreement can be found between the experimental data and the theoretical calculations performed using Hartree-Fock method with the different basis sets and configuration interaction method.

The torque measurement is one of important contents of transmission line. The non-contact torque measurement method with high precision and high stability is one of hotpots that research machine quantity measurement in various countries today. Therefore, research on a non-contact torque sensor based on screw-type differential transformer is put forward. The principle of this measurement method and relative structure are introduced in this paper. The experiment results show; the measurement principle is feasible; the designed torque sensor has better linearity and consistency; repeatability precision is less than or equal to 0.5%

This paper describes the modeling, design, fabrication and performance of a monolithic 2/spl sim/26 GHz PHEMT power amplifier with low noise characteristic. By using a distributed circuit and series gate capacitors, the measured gain is 6.5/spl plusmn/0.5 dB with both in and out VSWR less than 2.0 in the broad band, and the measured output power is over 300 mW with 3.5/spl sim/5.5 dB noise figure in 2/spl sim/20 GHz frequency range. The amplifier is truly monolithic, with all matching and biasing and DC block circuitry included on the chip. The finished chip size is 3.2 mm/spl times/1.275 mm/spl times/0.1 mm.

Two integral outer envelope GTPases, Toc34 and Toc86, are proposed to regulate the recognition and translocation of nuclear-encoded preproteins during the early stages of protein import into chloroplasts. Defining the precise roles of Toc86 and Toc34 has been complicated by the inability to distinguish their GTPase activities. Furthermore, the assignment of Toc86 function is rendered equivocal by recent reports suggesting that the standard protocol for the isolation of chloroplasts results in significant proteolysis of Toc86 (B. Bolter, T. May, J. Soll [1998] FEBS Lett 441: 59-62; G. Schatz [1998] Nature 395: 439-440). We demonstrate that Toc86 corresponds to a native protein of 159 kD in pea (Pisum sativum), designated Toc159. We take advantage of the proteolytic sensitivity of Toc159 to selectively remove its 100-kD cytoplasmic GTPase domain and thereby distinguish its activities from other import components. Proteolysis eliminates detectable binding of preproteins at the chloroplast surface, which is consistent with the proposed role of Toc159 as a receptor component. Remarkably, preprotein translocation across the outer membrane can occur in the absence of the Toc159 cytoplasmic domain, suggesting that binding can be bypassed. Translocation remains sensitive to GTP analogs in the absence of the Toc159 GTP-binding domain, providing evidence that Toc34 plays a key role in the regulation of translocation by GTP.

The exponential variation method is applied to the charge exchange in H++ H collisions in the present paper. The angular distributions have been calculated practically for two incident energies, 60 and 125 keV. The present results show that the obvious improvement with respect to BIB approximation can be obtained by the exponential variation method.