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The human papillomavirus type 16 (HPV16) life cycle can be divided into an early stage in which the HPV16 genomic DNA is replicated, and a late stage in which the HPV16 structural proteins are synthesized and virions are produced. A strong coupling between the viral life cycle and the differentiation state of the infected cell is highly characteristic of all HPVs. The switch from the HPV16 early gene expression program to the late requires a promoter switch, a polyadenylation signal switch and a shift in alternative splicing. A number of cis-acting RNA elements on the HPV16 mRNAs and cellular and viral factors interacting with these elements are involved in the control of HPV16 gene expression. This review summarizes our knowledge of HPV16 cis-acting RNA elements and cellular and viral trans-acting factors that regulate HPV16 gene expression at the level of splicing and polyadenylation. [ABSTRACT FROM AUTHOR]

Particle damping is a kind of passive and strongly nonlinear damping for energy dissipation. Many researchers have expended huge amounts of effort and time to study internal mechanism of particle damping. However, there is not a systematic and feasible approach for estimating damping performance of non-obstructive particle damping (NOPD). In this paper, we performed studies to mathematically evaluate the damping effect of particle damping based on principles of gas-solid flows. In consideration of the structural characteristics of NOPD which granular materials should be filled into sealed cavity of vibrating structure and the damping act on lateral and bottom of holes in NOPD technology, the gross damping is divided into lateral damping and bottom damping by Janson's theory of stress change direction. And the damping coefficients are compiled into a plug-in by MATLAB and are invoked in FEM software by enterprise integration kits of COMSOL. Meanwhile the frequency domain and time domain analysis of the experiment are used to verify the prediction accuracy of dynamic vibration response of an aluminium cantilever beam which ONPD is imposed at the free end with different packing rate and granular material, the result indicate that the mathematical model has excellent performance to predict the dynamic vibration response of NOPD. Then, the relationship damping effect with the particle filling ratio, particle density and length-diameter ratio of the hole is also researched using co-simulation, it should be noted that larger packing rate and particle density, smaller length-diameter ratio of the hole can play excellent damping effects in NOPD. [ABSTRACT FROM AUTHOR]

Low-noise, energy-saving and improved sound quality has been the major concern for the eco-design of household appliance product. In this paper, taking off from vibro-acoustic coupling, a composite noise control scheme (CNCS) combined with dynamic vibration absorbing technology, the sound absorption technique, controlling noise in the outlet, and particle damping technique is developed to control the sound radiation from an outdoor unit of a split air-conditioner based on sound sources identification. With the help of developed experiment platform, application effect of each technology and CNCS are measured, experimental evaluation shows that the developed CNCS can reduce the sound pressure level (SPL) more than 10 dB. To clarify the application effect of CNCS in sound quality further, it should be evaluated subjectively by using experiments. Experimental result shows that the stability and smoothness of the unit's noise have been greatly improved in time domain signal of sound pressure, the fluctuation strength is greatly improved for the controlled unit, the value at the left ear is reduced from 0.0195 vacil to 0.0146 vacil, and the right ear value is 0.0141 vacil instead of 0.0251 vacil. In addition, the sharpness has also been significantly reduced after CNCS, the value at the left ear decreases from 2.11 acum to 1.97 acum, and 2.01 acum to 1.86 acum for the right ear. So, CNCS is a pragmatic technique to control noise, vibration and improving sound quality. [ABSTRACT FROM AUTHOR]

The particle damper as a passive means for vibration suppression, is preferred due to its simplicity and easy to implement and control, with no need for any auxiliary power equipment. The bottleneck of the design for the particle damper is that damping performance is influenced by many parameters including particle material and size, packing ratio and cavity dimensions of enclosure such as length, width and diameter. In fact, the overall damping effect of particle damper is closely related to the primary structure system parameters. However, the influences of the excitation point, dampers arrangements, excitation force amplitude, and excitation force type for overall damping effect are scarce reported in the open literatures. How to exert particle damper on the structure and how many particles filled within the cavity, which are needed to face the problem in the engineering practice. In the face of doubt above-mentioned, the above questions will be clarified in this paper. At the same time, an optimization algorithm by the application of genetic algorithms of BP neural network is carried out in order to get most excellent damping effect. These will offer significance guidance to design and conduct particle dampers implement in the specific engineering practice with reference significance. [ABSTRACT FROM AUTHOR]

Ethylene response factors (ERFs) comprise a large family of transcription factors that regulate numerous biological processes including growth, development, and response to environmental stresses. Here, we report that Pti5, an ERF in tomato [Solanum lycopersicum (Linnaeus)] was transcriptionally upregulated in response to the potato aphid Macrosiphum euphorbiae (Thomas), and contributed to plant defences that limited the population growth of this phloem-feeding insect. Virus-induced gene silencing of Pti5 enhanced aphid population growth on tomato, both on an aphid-susceptible cultivar and on a near-isogenic genotype that carried the Mi-1.2 resistance (R) gene. These results indicate that Pti5 contributes to basal resistance in susceptible plants and also can synergize with other R gene-mediated defences to limit aphid survival and reproduction. Although Pti5 contains the ERF motif, induction of this gene by aphids was independent of ethylene, since the ACC deaminase (ACD) transgene, which inhibits ethylene synthesis, did not diminish the responsiveness of Pti5 to aphid infestation. Furthermore, experiments with inhibitors of ethylene synthesis revealed that Pti5 and ethylene have distinctly different roles in plant responses to aphids. Whereas Pti5 contributed to antibiotic plant defences that limited aphid survival and reproduction on both resistant (Mi-1.2+) and susceptible (Mi-1.2-) genotypes, ethylene signalling promoted aphid infestation on susceptible plants but contributed to antixenotic defences that deterred the early stages of aphid host selection on resistant plants. These findings suggest that the antixenotic defences that inhibit aphid settling and the antibiotic defences that depress fecundity and promote mortality are regulated through different signalling pathways. [ABSTRACT FROM AUTHOR]

This paper presents a vertical vibration model for 2:1-roping traction elevator system. In this model, masses of suspension ropes are considered and their kinetic energy is calculated by applying Rayleigh method. Equations of motion for free vibration are derived. To verify the improvement of the model, an output dependent only modal test scheme using eigenvalue realization algorithm is conducted to obtain natural frequencies from a real elevator installation. The comparison of experimental results and numerical results of proposed model and previous similar models is presented on calculation of natural frequencies. The results show that proposed model is able to reflect the 5th natural frequencies more exactly under 0 % and 100 % load conditions. [ABSTRACT FROM AUTHOR]

Quantum resources, such as discord and entanglement, are crucial in quantum information processing. In this paper, quantum resources are studied from the aspect of quantum state superposition. We define the local superposition (LS) as the superposition between basis of single part, and nonlocal superposition (NLS) as the superposition between product basis of multiple parts. For quantum resource with nonzero LS, quantum operation must be introduced to prepare it, and for quantum resource with nonzero NLS, nonlocal quantum operation must be introduced to prepare it. We prove that LS vanishes if and only if the state is classical and NLS vanishes if and only if the state is separable. From this superposition aspect, quantum resources are categorized as superpositions existing in different parts. These results are helpful to study quantum resources from a unified frame. [ABSTRACT FROM AUTHOR]

Entanglement dynamics for a couple of two-level atoms interacting with independent structured reservoirs is studied using a non-perturbative approach. It is shown that the revival of atom entanglement is not necessarily accompanied by the sudden death of reservoir entanglement, and vice versa. In fact, atom entanglement can revive before, simultaneously or even after the disentanglement of reservoirs. Using a novel method based on the population analysis for the excited atomic state, we present the quantitative criteria for the revival and death phenomena. To give a more physically intuitive insight, the quasimode Hamiltonian method is applied. Our quantitative analysis is helpful for the practical engineering of entanglement. [ABSTRACT FROM AUTHOR]

A series of bedaquiline analogs containing H-bond donors were designed as anti-Mycobacterium tuberculosis drugs. A pair of diastereoisomers (R/S- and S/S-isomers) was selected from these designed compounds for synthetic and stereochemical research. The title compounds were synthesized from chiral precursors for the first time and the absolute configurations (ACs) were determined by electronic circular dichroism (ECD) with quantum chemical calculations. Moreover, a single crystal of the S/S compound was obtained for X-ray diffraction analysis, and the crystal structure showed high consistency with the geometry, confirming the reliability of ACs obtained by ECD analyses and theoretical simulation. Furthermore, the effect of stereochemistry on the anti-tuberculosis activity was investigated. The MICs of the R/S- and S/S-isomers against Mycobacterium phlei 1180 are 9.6 and 32.1 μg·mL–1, respectively. Finally, molecular docking was carried out to evaluate the inhibitory nature and binding mode differences between diastereoisomers. [ABSTRACT FROM AUTHOR]

We investigated the effects of Baicalin and Octreotide on the levels of endotoxin and TNF-α in blood and the effects of apoptotic changes in multiple organs of SAP rats, and explored the underlying therapeutic mechanisms of Baicalin and Octreotide. In this study, 135 SAP rats were randomly divided into model control, Baicalin treated and Octreotide treated group ( n = 45), respectively, the same number of normal rats were included in sham-operated group ( n = 45). The above-mentioned groups were further subdivided into 3, 6 and 12 h subgroups, respectively (15 rats in each subgroup). At 3, 6 and 12 h after operation, the mortality rate of rats, endotoxin and TNF-α levels in blood as well as the pathological severity scores, expression levels of Bax protein and apoptosis indexes in multiple organs were determined. Compared to model control group (1),both drugs can relieve the pathological injuries of multiple organs and decrease significantly the levels of endotoxin and TNF-α in blood and the mortality rate of rats in treated groups ( P < 0.05 or P < 0.01); (2) the expression of Bax protein was upregulated in pancreas, lung, intestinal mucosa ( P < 0.05 or P < 0.01) but downregulated in spleen and lymph nodes ( P < 0.001 and P < 0.05, respectively) in Baicalin treated group; The apoptosis indexes significantly increased in pancreas, intestinal mucosa, lymph nodes and spleen ( P < 0.05 or P < 0.01). (3) the expression of Bax protein was upregulated in pancreas and lung but downregulated in spleen and lymph nodes ( P < 0.05 or P < 0.01) in Octreotide treated group; The apoptosis indexes significantly increased in lymph nodes and spleen in Octreotide treated group ( P < 0.05 or P < 0.01). Baicalin and Octreotide share a similar therapeutic efficacy in the treatment of SAP via a mechanism that is associated with inhibiting the levels of TNF-α in blood and induce apoptosis in multiple organs. [ABSTRACT FROM AUTHOR]

Human papillomavirus 16 (HPV16) 5'-splice site SD226 and 3'-splice site SA409 are required for production of the HPV16 E7 mRNAs, whereas unspliced mRNAs produce E6 mRNAs. The E6 and E7 proteins are essential in the HPV16 replication cycle but are also the major HPV16 proteins required for induction and maintenance of malignancy caused by HPV16 infection. Thus, a balanced expression of unspliced and spliced mRNAs is required for production of sufficient quantities of E6 and E7 proteins under physiological and pathophysiological conditions. If splicing becomes too efficient, the levels of unspliced E6 mRNAs will decrease below a threshold level that is no longer able to produce E6 protein quantities high enough to significantly reduce p53 protein levels. Similarly, if splicing becomes too inefficient, the levels of spliced E7 mRNAs will decrease below a threshold level that is no longer able to produce E7 protein quantities high enough to significantly reduce pRb protein levels. To determine how splicing between SD226 and SA409 is regulated, we have investigated how SA409 is controlled by the cellular proteins hnRNP A1 and hnRNP A2, two proteins that have been shown previously to control HPV16 gene expression. We found that hnRNP A1 and A2 interacted directly and specifically with a C-less RNA element located between HPV16 nucleotide positions 594 and 604 downstream of SA409. Overexpression of hnRNP A1 inhibited SA409 and promoted production of unspliced E6 mRNAs at the expense of the E7 mRNAs, whereas overexpression of hnRNP A2 inhibited SA409 to redirect splicing to SA742, a downstream 3'-splice site that is used for generation of HPV16 E6E7, E1, and E4 mRNAs. Thus, high levels of either hnRNP A1 or hnRNP A2 inhibited production of the promitotic HPV16 E7 protein. We show that the hnRNP A1 and A2 proteins control the relative levels of the HPV16 unspliced and spliced HPV16 E6 and E7 mRNAs and function as inhibitors of HPV16 E7 expression. [ABSTRACT FROM AUTHOR]

Salt is a severe abiotic stress that reduces soybean [Glycine max (L.) Merr.] yield by >20% in saline soils and irrigated fields. Marker-assisted selection (MAS) is an efficient method to identify salt-tolerant soybean lines. 'Osage' is a salt-tolerant and high-yielding cultivar in the Mid-South of the United States and is a distant progeny tracing five generations back to 'S-100'. The objective of this study was to determine the inheritance of salt tolerance in Osage soybean by identifying the quantitative trait loci (QTL) controlling the trait. A chloride (Cl-) includer, 'RA-452', was crossed with Cl- excluder, Osage, to develop an F4:6 mapping population. The F4:6 lines were genotyped by 5403 single nucleotide polymorphism (SNP) markers spanning 20 chromosomes (Chr.), of which, 1269 were polymorphic. The salt stress response of F4:6 lines, along with parental genotypes, was evaluated in the greenhouse in April and June 2013. Three different treatments (120 mM NaCl, 120 mM KCl, and water) were initiated at V1 stage and continued for ~18 to 21 d. The leaf Cl- contents were quantified by inductively coupled plasma optical emission spectroscopy. Composite interval mapping analysis indicated that a major Cl--tolerant QTL was confirmed and narrowed down on Chr. 3 in both NaCl and KCl treatments, a novel Cl--tolerant QTL on Chr. 15 was identified in NaCl treatment, and a novel Cl--tolerant QTL on Chr. 13 was identified in the KCl treatment. Two annotated genes, Glyma.13G161800 and Glyma.15G091600, were proposed to be the candidate gene conferring the Cl- tolerance within QTL region on Chr. 13 and 15, respectively. A total of 27 SNP markers were significantly associated with Cl- tolerance, which could be used for MAS in breeding salt-tolerant soybean lines. [ABSTRACT FROM AUTHOR]

Soybean mosaic virus (SMV), a member of the Potyviridae family, is the most common virus negatively affecting yield and seed quality in soybean [Glycine max (L.) Merr.]. Seven SMV strains, G1 through G7, and three independent SMV resistance genes (R-genes), Rsv1, Rsv3, and Rsv4, have been previously identified. The Rsv1 locus contains at least 10 alleles conferring differential plant reactions to SMV strains, and it was mapped at very complex resistancegene-rich region. In this study, two alleles of the Rsv1 locus were analyzed by crossing PI 96983 (Rsv1) and cultivar York (Rsv1-y) soybean to evaluate whether Rsv1 and Rsv1-y belong to the same or different but closely linked loci. To break possible linkage, 3000 F2:3 lines were developed and investigated using infections of the SMVG1 strain in a greenhouse. The occurrence of segregating and susceptible lines indicated tight linkage between two genes. The recombination frequency (RF) was estimated using the maximum likelihood (ML) formula concluding that Rsv1 and Rsv1-y are two tightly linked loci located apart with genetic distance of 2.2 cM on chromosome 13. A new symbol of Rsv5 has been assigned for the resistance gene in York to replace the original Rsv1-y allele assignment. This research provided the first evidence for existence of two R-genes on chromosome 13, conferring resistance to different SMV strains. Both loci, Rsv1 and Rsv5, can be easily transferred into susceptible cultivars in a breeding program to provide broad and durable protection against SMV strains. [ABSTRACT FROM AUTHOR]

Information on biomass yield and forage nutritive value of grain- and forage-type soybean [Glycine max (L.) Merr.] cultivars is of interest to livestock and row-crop farmers. We studied grain and forage genotypes for biomass, forage nutritive value, and seed yield across two Arkansas locations over 2 yr. Results revealed that stem and total biomass at the R1 (beginning bloom) reproductive growth stage were significantly greater in forage genotypes than in grain genotypes. Forage genotypes had a greater amount of stem biomass (208.7 and 484.0 g m-2) at both R1 and R6 stages and leaf biomass (246.2 g m-2) at R1 than grain genotypes (140.4, 309.2, and 243.8 g m-2, respectively). At R6, grain genotypes had greater amounts of leaf (388.3 g m-2) and pod biomass (350.5 g m-2) than forage genotypes (350.4 and 272.5 g m-2, respectively). There were no differences in leaf and total biomass between forage and grain genotypes at R6. Grain genotypes showed significantly greater seed yield than the forage genotypes (2662.3 vs. 1320.2 kg ha-1), but no differences in seed protein and oil. Forage genotypes had less crude protein and greater acid detergent fiber than grain genotypes, while their neutral detergent fiber concentrations varied among growth stages. Forage soybeans had lower forage nutritive value than grain soybeans overall. For the southern latitude of Arkansas and southern states, we recommend the late-maturing forage genotypes 'Tyrone' and 'SG13-53' and grain genotypes 'Arksoy' and 'Centennial' for planting as forage crops. Our results provide valuable information to growers of these distinctly different soybean types. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the radiosensitizing effects of homeobox (HOX) transcript antisense RNA (HOTAIR) long non-coding RNA on breast cancer tumor cells and examine the underlying mechanisms. Recombinant plasmid vectors containing HOTAIR gene were constructed and MDA-MB231 cells were transfected with these plasmids using liposomes. The cells were treated with radiation and cell apoptosis, proliferation, and double-stranded DNA breaks were examined. HOXD10, phosphorylated AKT (p-AKT) and p-BAD expression levels were measured using western blot analysis. The results showed a higher expression of HOTAIR in advanced tumor cells. HOTAIR efficiently enhanced radioresistance in MDA-MB231 breast cancer cells and accelerated proliferation through the Akt pathway by targeting HOXD10. In conclusion, the findings demonstrated that HOTAIR gene is a valid therapeutic target for the reversal of radiotherapy resistance in breast cancer. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented concerning simultaneous pancrease-kidney transplantation for diabetic end-stage renal disease under a hypertension status.

The simple gaseous compound ethylene (ET) has long been recognized as a common component of plant responses to insect feeding and pathogen attack. However, it is presently uncertain whether it plays a role in host–plant resistance to piercing–sucking insects such as aphids. In these experiments, we investigated the expression of key ET-associated genes in resistant and susceptible interactions in two model systems: the tomato- Mi- Macrosiphum euphorbiae (Thomas) (Hemiptera: Aphididae: Macrosiphini) system and the melon-virus aphid transmission gene ( Vat)- Aphis gossypii Glover (Hemiptera: Aphididiae: Aphidini) system. We examined expression patterns of genes associated with ET synthesis, perception, signal transduction, and downstream response. When compared with control plants, plants infested with aphids showed marked differences in gene expression. In particular, ET signaling pathway genes and downstream response genes were highly upregulated in the resistant interaction between A. gossypii and Vat +, indicating ET may play a role in Vat-mediated host–plant resistance. A key integrator between the ET and jasmonic acid pathways ( Cm-ERF1) showed the strongest response. [ABSTRACT FROM AUTHOR]

Flowering represents a crucial transition from a vegetative to a reproductive phase of the plant life cycle. Despite extensive studies, the molecular mechanisms controlling flowering remain elusive. Although the enzymes involved are unknown, methylation of histone H3 K9 and K27 correlates with repression of FLOWERING LOCUS C (FLC), an essential transcriptional repressor involved in flowering time control in Arabidopsis thaliana; in contrast, methylation of H3K4 correlates with FLC activation. Here we show that loss-of-function of SET DOMAIN GROUP 8 (SDG 8), which encodes a homologue of the yeast SET2 histone methyltransferase, results in reduced dimethylation of histone H3K36, particularly in chromatin associated with the FLC promoter and the first intron, regions that contain essential cis-elements for transcription. sdg8 mutants display reduced FLC expression and flower early, establishing SDG8-mediated H3K36 methylation as a novel epigenetic memory code required for FLC expression in preventing early flowering. This is the first demonstrated role of H3K36 methylation in eukaryote development. [ABSTRACT FROM AUTHOR]