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A dual-band tunable balanced filter based on one hybrid microstrip-cavity structure is proposed in this paper. The cavity acts as one multimode resonator, and the differential feeding networks are printed on the PCBs. According to the electromagnetic (EM) field theory, TE101 and TE011 modes are generated under differential-mode (DM) excitation, and highly suppressed under common-mode (CM) excitation. The dielectric posts in the cavity can independently shift the resonant frequencies of the two modes. Moreover, the inter-resonator coupling of each band is independently controlled by the cross-shaped coupling slot. Therefore, good filtering differential response can be realized with in a wide band. For demonstration, a dual-band tunable balanced filter is designed and measured. The measured results indicate that the center frequencies of the two bands are tuned from 7.51 GHz to 8.22 GHz and 9.34 GHz to 10.56 GHz, respectively. Over the tuning range, the insertion losses vary from 0.5 dB to 1.5 dB and the CM suppressions in both passbands are under 50 dB and 42 dB. In this way, the proposed hybrid microstrip-cavity structure is feasible to design a reconfigurable balanced filter with wide tuning range and high CM suppression.

Background The infraorder Rhigonematomorpha comprises a group of obligate parasitic nematodes of millipedes (Arthropoda: Diplopoda). The current species identification of Rhigonematomorpha nematodes remains mainly based on morphological features, with molecular-based identification still in its infancy. Also, current knowledge of the phylogeny of Rhigonematomorpha is far from comprehensive. Methods The morphology of Rhigonematomorpha nematodes belonging to the genus Rhigonema, collected from the millipede Spirobolus bungii Brandt (Diplopoda: Spirobolida) in China, was studied in detail using light and scanning electron microscopy. Five different genetic markers, including the nuclear small ribosomal subunit (18S), internal transcribed spacer (ITS) and large ribosomal subunit (28S) regions and the mitochondrial cox1 and cox2 genes of these Rhigonematomorpha nematodes collected from China and Rhigonema naylae collected from Japan were sequenced and analyzed using Bayesian inference (BI) and Assemble Species by Automatic Partitioning (ASAP) methods. Phylogenetic analyses that included the most comprehensive taxa sampling of Rhigonematomorpha to date were also performed based on the 18S + 28S genes using maximum likelihood (ML) and BI methods. Results The specimens of Rhigonema collected from S. bungii in China were identified as a new species, Rhigonema sinense n. sp. Striking variability in tail morphology was observed among individuals of R. sinense n. sp. ASAP analyses based on the 28S, ITS, cox1 and cox2 sequences supported the species partition of R. sinense n. sp. and R. naylae, but showed no evidence that the different morphotypes of R. sinense n. sp. represent distinct genetic lineages. BI analyses also indicated that R. sinense n. sp. represents a separated species from R. naylae based on the cox1 and cox2 genes, but showed that R. naylae nested in samples of R. sinense n. sp. based on the ITS and 28S data. Phylogenetic results showed that the representatives of Rhigonematomorpha formed two large clades. The monophyly of the families Carnoyidae and Ichthyocephalidae and the genus Rhigonema was rejected. The representatives of the family Ransomnematidae clustered together with the family Hethidae with strong support. Conclusions A new species of Rhigonematomorpha, R. sinense n. sp. is described based on morphological and molecular evidence. ASAP analyses using 28S, ITS, cox1 and cox2 data indicate the striking variability in tail morphology of R. sinense n. sp. as intraspecific variation, and also suggest that partial 28S, ITS, cox1 and cox2 markers are effective for molecular identification of Rhigonematomorpha nematodes. The phylogenetic results support the traditional classification of Rhigonematomorpha into the two superfamilies Rhigonematoidea and Ransomnematoidea, and indicate that the families Carnoyidae and Ichthyocephalidae and the genus Rhigonema are non-monophyletic. The present phylogeny strongly supports resurrection of the family Brumptaemiliidae, and also indicates that the family Ransomnematidae is sister to the family Hethidae. Graphical Abstract

Gas field C is an unconventional tight gas reservoir located in the central of China which has prominent characteristics, including thin formation, low permeability and poor reservoir connectivity which significantly impact on the field development. Horizontal wells multistage hydraulic fracturing has been proven to be an effective technique to recover the hydrocarbons from this gas field. However, with continuous production overtime, reservoir pressure declines which results in a decrease in gas production rate below the critical gas velocity, leading to accumulation of liquid in the wellbore (liquid loading), which further results in back pressure and damage to the formation. Currently, gas field C loses up to 1500 mmscf/year in gas production and associated revenue due to liquid loading. Some other factors which hinders effective deliquification of the gas wells include remote well pad locations, poor road conditions during harsh weather conditions, friction with local communities, limited manpower to daily effectively analyze over 200 wells for liquid loading diagnostics and operational risks during well intervention. To tackle these challenges, a new versatile intelligent dosing technology has been piloted to reduce liquid loading. This remote-control dosing unit is located at the well pad and is equipped with automatic valves that can dispense two different chemicals (soap and methanol) in one unit. A key new feature of this system is the ability to receive and implement instructions that optimizes the dosing rate and frequency. This remote-control functionality eliminates on-site operator intervention and HSE risks especially in winter when the well pads could be inaccessible with poor road conditions.

Subulura chinensis Schwartz, 1926 is a hitherto poorly known nematode species. The morphology of S. chinensis has not been sufficiently well described. In addition, the molecular data from species of the Subuluroidea are extremely limited. The detailed morphology of S. chinensis was studied using light microscopy and, for the first time, scanning electron microscopy, based on newly collected specimens from the little owl Athene noctua (Scopoli) (Strigiformes: Strigidae) in China. The internal transcribed spacer (ITS) of ribosomal DNA and mitochondrial cytochrome c oxidase subunit 1 (cox1) target regions of S. chinensis were first amplified by polymerase chain reaction (PCR), then sequenced and analysed for the molecular identification of this species. Our SEM observations showed for the fist time the detailed morphology of the cephalic extremity, precloacal pseudo-sucker, caudal papillae, gubernaculum, phasmids and vulva of S. chinensis, and also determined the presence of a small, single medio-ventral precloacal papilla in the male. Moreover, we detected the presence of 0.08–0.40% and 0–1.30% nucleotide divergence among different individuals of S. chinensis in the ITS and cox1 regions, respectively. The supplementary morphological characters and genetic data will be very useful for the diagnosis of this poorly known species.

Aiming at the defects of repeating searching the path, low efficiency and the slow speed of the traditional topology algorithm, proposes a network topology algorithm based on Breadth-First-Search in this paper.Introduces the topology modeling method,and the electric equipment is abstracted into nodes and branches,making the topology process not constrained by the network connection and structure,enhancing universal property of the algorithm.Then introduces the traditional method, and analysises the disadvantages. At the same time,puts forward a new method. Uses node-branch adjacency list in the new method,which improves the topology speed.When the local switch information is changed, can modify the node-branch adjacency list to conduct the local re-topology,so it improves the topology flexibility. Finally, through the example, proves the superiority and practicability of this algorithm.

The quaternary TixZr1-xMnFe gettering alloys (x =0, 0.1, 0.2, 0.3 and 0.4) were synthesized successfully by arc melting and their phase structures along with microstructures had been investigated by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). It showed that the addition of Ti did not change the phase structure of ZrMnFe of C14 laves phase. XRD results showed that Ti successfully replaced part of the Zr and the decrease of interplanar spacing had a linear relationship with the increase of Ti content. The success of this trial preparation provides reference for nuclear industry gettering materials.

A new copper(II) complex, [Cu(naph-leu)phen]CH3OH·0.5H2O, in which naph-leu is the tridentate Schiff base ligand derived from the condensation of 2-hydroxy-1-naphthaldehyde and L-leucine, phen is phenanthroline, has been synthesized and characterized by elemental analyses, IR spectra and single crystal X-ray diffraction. The DNA-binding properties of this complex have been investigated by absorption spectra, fluorescence spectra and circular dichroism (CD) spectra, as well as viscosity measurement. Results show that this copper(II) complex binds to calf thymus DNA (CT-DNA) in an intercalative mode and its intrinsic binding constant Kb is 4.87×103 L·mol−1. Furthermore, the DNA cleavage activity of this copper(II) complex has also been investigated by submarine gel electrophoresis. Interestingly, it was found that this complex can cleave the supercoiled plasmid pBR322 DNA to both nicked and linear forms.

The enthalpies of dilution of matrine (MAT) in pure water and aqueous sodium chloride solutions were determined by isothermal titration microcalorimetry at 298.15 K, and the corresponding homogeneous enthalpic interaction coefficients were calculated according to the modified McMillan–Mayer model. The values of enthalpic pair-wise interaction coefficients, h 2, are all positive and become more positive with increasing concentration of sodium chloride.

The low-temperature heat capacities of berberine hydrochloride were measured over the temperature range from 78 to 350 K by an adiabatic calorimeter. The thermodynamic functions H T − H 298.15 and S T − S 298.15 were derived from the heat capacity data. The results showed that the structure of berberine hydrochloride was stable over the temperature range from 78 to 350 K. The thermal stability of the compound was further tested by DSC and TG measurements. The results were in agreement with those obtained from adiabatic calorimetry experiment. The standard molar enthalpy of formation in the crystalline state of berberine hydrochloride was obtained from the standard molar energies of combustion in oxygen at T = 298.15 K, measured by a rotating-bomb combustion calorimeter.

The dilution enthalpies of D-mannitol and D-sorbitol in aqueous sodium chloride solution at various concentrations have been determined by isothermal microcalorimetry at 298.15 K. The homogeneous enthalpic interaction coefficients over a quite large range of concentration of aqueous sodium chloride solutions have been calculated according to the excess enthalpy concept. The results show that enthalpic pairwise interaction coefficients (h 2) of D-mannitol and D-sorbitol are positive in aqueous sodium chloride solution and become more positive with increase of the concentration of sodium chloride. The results are interpreted in terms of the different conformations of the two polyols, solute-solute and solute-solvent interactions involved by solvent effects.

A series of organotin (IV) compounds of the type [R3SnL]2, R is Me (1), Bu (2), [R2SnL]2, R is Ph (3), Me (4), Bu (5), L is pyruvic acid thiophene-2-carboxylic hydrazone, and R2SnL, R is Me (6), Bu (7), Ph (8), L is salicylaldehyde thiophene-2-carboxylic hydrazone have been synthesized in 1:1 molar ratio. All compounds were characterized by elemental analysis, IR, 1H NMR, 13C NMR and 119Sn NMR spectra. The crystal structure of compounds 1, 3, 4, 8 have been determined by X-ray single crystal diffraction analyses, study found that the compounds 1 and 3 are rendered one-dimensional chain structure and the tin atoms are five-coordinated in a distorted trigonal-bipyramidal geometry. The compound 4 has a dimeric structure and the central tin atom is rendered seven-coordinate in a distorted pentagonal-bipyramid configuration. While the compound 8 is a monomer in which the tin atom adopts five-coordinated in distorted trigonal-bipyramidal geometry.

A series of diorganotin(IV) and triorganotin(IV) compounds of the type [R2Sn(pca)2ClSnR3]2 (R PhCH2 1, 2-ClC6H4CH2 2, 2-FC6H4CH2 3, 4-FC6H4CH2 4, 4-CNC6H4CH2 5, 4-ClC6H4CH2 6, 2,4-Cl2C6H3CH2 7; Hpca 2-methylpyrazine-5-acid), [(nBu)3Sn(pca)]∞ 8, [(CH3)2Cl2Sn(pca)Sn(CH3)2(pca)]∞ 9, {[(nBu)2Sn(pca)]2O}2 10 and {[Ph2Sn(pca)]3O2[Ph2Sn(OCH3)]} 11 have been obtained by reactions of 2-methylpyrazine-5-acid with triorganotin(IV) chloride, diorganotin(IV) dichloride, and diorganotin(IV) oxide. All compounds were characterized by elemental, IR, and NMR spectra analyses. The crystal structure of compounds 1, 8–11 were determined by X-ray single crystal diffraction, which revealed that compound 1 was tetranuclear macrocyclic structures with seven-coordinate and five-coordinate tin atoms, compounds 8 and 9 were polymeric chain structures with five-coordinate and seven-coordinate tin atoms, compounds 10 and 11 were monomeric structures with six-coordinate and five-coordinate tin atoms.

To observe the efficacy of regular or intermittent inhalation of salmeterol/fluticasone propionate (SM/FP) in the treatment of bronchial asthma and its effects on growth and development in children.A total of 112 children diagnosed with bronchial asthma between September 2012 and October 2013 were assigned to standardized treatment (standard group, n=56) and non-standardized treatment (intermittent group, n=56). Comparisons of clinical symptom scores and main pulmonary function indicators between the two groups were carried out before treatment and at 6 and 12 months after treatment. The growth velocity and changes in body mass index (BMI) were observed in the two groups.At 6 and 12 months after the treatment, the standard group had significantly reduced clinical symptom scores and significantly increased pulmonary function indicators (percentage of predicted peak expiratory flow, PEF%; percentage of forced expiratory volume in 1 second, FEV1%) (P0.05); the intermittent group had significantly reduced clinical symptom scores and significantly increased FEV1% (P0.05), but PEF% was significantly increased only at 6 months after treatment (P0.05). At 12 months after treatment, the standard group had significantly lower clinical symptom scores and significantly higher PEF% and FEV1% when compared with the intermittent group (P0.05). The growth velocity and BMI showed no significant differences between the two groups at 6 and 12 months after treatment (P0.05).Compared with intermittent inhalation, long-term regular inhalation of SM/FP performs better in controlling clinical symptoms and enhancing pulmonary function in children with asthma. Inhalation of SM/FP for one year reveals no apparent effect on the growth and development of these children.

Low-temperature heat capacities of a solid complex Zn(Val)SO4·H2O(s) were measured by a precision automated adiabatic calorimeter over the temperature range between 78 and 373 K. The initial dehydration temperature of the coordination compound was determined to be, TD=327.05 K, by analysis of the heat-capacity curve. The experimental values of molar heat capacities were fitted to a polynomial equation of heat capacities (Cp,m) with the reduced temperatures (x), [x=f (T)], by least square method. The polynomial fitted values of the molar heat capacities and fundamental thermodynamic functions of the complex relative to the standard reference temperature 298.15 K were given with the interval of 5 K. Enthalpies of dissolution of the [ZnSO4·7H2O(s)+Val(s)] (Δsol Hm,l0) and the Zn(Val)SO4·H2O(s) (Δsol Hm,20) in 100.00 mL of 2 mol dm−3 HCl(aq) at T=298.15 K were determined to be, Δsol Hm,l0=(94.588±0.025) kJ mol−1 and Δsol Hm,20=–(46.118±0.055) kJ mol−1, by means of a homemade isoperibol solution–react...

Low-temperature heat capacities of the solid coordination compound Zn(Leu)SO(4)center dot 1/2H(2)O(s) were measured by a precision automated adiabatic calorimeter over the temperature range between T = 78 K and T = 371 K. The initial dehydration temperature of the coordination compound was determined to be T-D = 326.50 K by analysis of the heat-capacity curve. The experimental values of molar heat capacities were fitted to a polynomial equation of heat capacities (C-p,C-m) with the reduced temperatures (x), [x = f (T)] by least-squares method. Enthalpies of dissolution of the [ZnSO(4)center dot 7H(2)O(s) + Leu(s)] ( Delta(sol)H degrees(m,1)) and the Zn(Leu)SO(4)center dot 1/2H(2)O(s) (Delta(sol)H degrees(m,2)) in 100.00 mL of 2 mol center dot dm(-3) HCl(aq) at T = 298.15 K were determined to be Delta solH degrees(m,1) = -(85.80 +/- 0.09) kJ center dot mol(-1) and Delta solH(m,2) = (55.97 +/- 0.06) kJ center dot mol(-1) by means of a homemade isoperibol solution-reaction calorimeter. The standard molar enthalpy of formation of the compound was determined as Delta H degrees(m)(Zn(Leu)SO(4)center dot 1/2H(2)O, s, 298.15 K) = -(1999.0 +/- 0.9) kJ center dot mol(-1) from the enthalpies of dissolution and other auxiliary thermodynamic data through a Hess thermochemical cycle. Furthermore, the reliability of the Hess thermochemical cycle was verified by comparing UV/Vis spectra and the refractive indexes of solution A (from dissolution of the [ZnSO(4)center dot 7H(2)O(s) + Leu(s)] mixture in 2 mol center dot dm(-3) hydrochloric acid) and solution A' (from dissolution of the complex Zn(Leu)SO(4)center dot 1/2H(2)O(S) in 2 mol center dot dm(-3) hydrochloric acid).

The two solid-state coordination reactions (1) CuAc 2 · H 2 O ( s )+2 Ala ( s )→trans- Cu ( Ala ) 2 ( s )+2 HAc ( l )+ H 2 O ( l ) (2) CuAc 2 · H 2 O ( s )+2 Gly ( s )→trans- Cu ( Gly ) 2 · H 2 O ( s )+2 HAc ( l ) have been studied by solution calorimetry. The molar dissolution enthalpies of the reactants and the products in some solvents (such as 2 mol l−1 HCl or its solutions) of these solid–solid coordination reactions have been measured by an isoperibol solution calorimeter. The standard molar formation enthalpies of [trans-Cu(Ala)2(s), 298.15 K] and [trans-Cu(Gly)2(s), 298.15 K] have been determined to be −1015.42 ± 0.06 and 1252.36 ± 0.05 kJ mol−1, respectively, from the results of the molar dissolution enthalpies and other auxiliary thermodynamic data.

The solid-state coordination reactions: 2 HQ ( s )+ Co ( Ac ) 2 ·4 H 2 O ( s )→ Co ( HQ ) 2 ·2 H 2 O ( s )+2 HAc ( l )+2 H 2 O ( l ) 2 HQ ( s )+ Zn ( Ac ) 2 ·2 H 2 O ( s )→ Zn ( HQ ) 2 · H 2 O ( s )+2 HAc ( l )+ H 2 O ( l ) have been studied by solution calorimetry. The molar dissolution enthalpies of the reactants and the products in a certain solvent, 4 mol l −1 HCl, of this solid–solid coordination reaction have been measured using an isoperibol calorimeter. From the results and other auxiliary quantities, the standard molar formation enthalpies of [Co(HQ) 2 ·2H 2 O(s), 298.15 K], [Zn(HQ) 2 ·H 2 O(s), 298.15 K] and have been determined to be Δ f H m Θ (Co(HQ) 2 ·2H 2 O(s), 298.15 K)=−766.9±3.0 kJ mol −1 , Δ f H m Θ (Zn(HQ) 2 ·H 2 O(s), 298.15 K)=−580.7±3.0 kJ mol −1 .

Solubilities of potassium tetraphenylborate in water, methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, and 1-octanol at 15, 25, 35, 45, 55°C have been determined by spectrophotometry. The standard Gibbs energy of transfer of potassium tetraphenylborate form water to straightchain n-alkanols and the medium effect of potassium tetraphenylborate from 15 to 55°C have been calculated. Furthermore, the contribution of microscopic interactions to the standard Gibbs energy of transfer of potassium tetraphenylborate is calculated and discussed.

To investigate the mechanism of loss of human esophageal cancer-related gene 4 (ECRG4) expression in esophageal squamous cell carcinoma (ESCC.)PCR-SSCP and DNA sequencing analysis were used to detect the mutation of ECRG4 exons in esophageal cancer and matched adjacent normal tissues of 80 patients. DNA bisulfite-modifying ssPCR sequencing assay was used to examine the methylation status of ECRG4 promoter in human esophageal squamous cell carcinoma EC9706 cells. The re-expression of ECRG4 mRNA was examined by RT-PCR in EC9706 cells, after treatment with either demethylation drug 5-aza-2'-deoxycytidine or arsenic trioxide.No mutation in the four ECRG4 exons was found in all the ESCC and matched normal adjacent tissues. RT-PCR showed that 11 of 16 CpG islands of ECRG4 promoter were hypermethylated, while ECRG4 mRNA expression level was undetectable in the EC9706 cells. The ECRG4 mRNA was re-expressed after treatment with either demethylation drug 5-aza-2'-deoxycytidine or arsenic trioxide.The epigenetic mechanism of methylation is a reason of loss of ECRG4 gene expression in the ESCC cell line EC9706.

To investigate the tumor-suppressing function of human esophageal cancer related gene 4 (ECRG4) in esophageal squamous cell carcinoma (ESCC).The recombinant plasmid pcDNA3.1-ECRG4 with ECRG4 open reading frame was constructed. The EC9706 cell was transfected with either pcDNA3.1 or pcDNA3.1-ECRG4. And the effects of ECRG4 on tumor cell were examined by in vivo assays of cell proliferation, adhesion, migration, invasion and tumor growth. The expression levels of P53 and P21 proteins were detected in EC9706 cell with transfection of ECRG4 gene by Western blotting.The final tumor volume and weight in ECRG4 transfection group were (264±43) mm3 and (0.39±0.09) g, versus (464±128) mm3 and (0.76±0.13) g in control group (both P0.05). And the capacities of tumor cells adhesion, migration and invasion decreased in ECRG4 transfection group versus that in control group (all P0.05). Furthermore, the expression levels of P53 and P21 proteins were higher in ECRG4 transfection group than those in control group (100.00±3.87, 35.71±2.36 vs 16.6±1.92, 1.09±0.11, both P0.05).As a novel candidate tumor suppressor in ESCC, ECRG4 may induce the up-regulation of p21 protein through p53 pathway to inhibit tumor growth in ESCC.

Microtubule (MT) kinesin motor proteins orchestrate various cellular processes (e.g. mitosis, motility and organelle transportation) and have been implicated in human carcinogenesis. Kif18A, a plus-end directed MT depolymerase kinesin, regulates MT dynamics, chromosome congression and cell division. In this study, we report that Kif18A is overexpressed in human breast cancers and Kif18A overexpression is associated with tumor grade, metastasis and poor survival. Functional analyses reveal that ectopic overexpression of Kif18A results in cell multinucleation, whereas ablation of Kif18A expression significantly inhibits the proliferative capability of breast cancer cells in vitro and in vivo. Inhibition of Kif18A not only affects the critical mitotic function of Kif18A but also decreases cancer cell migration by stabilizing MTs at leading edges and ultimately induces anoikis of cells with inactivation of the phosphatidylinositol 3-kinase-Akt signaling pathway. Together, our results indicate that Kif18A is involved in human breast carcinogenesis and may serve as a potential therapeutic target for human breast cancer.

To investigate the correlation between the lack of estrogen receptor (ER) gene expression and hypermethylation of ER gene, and detect whether re-expressed ER protein is activated.The methylation status of ER gene promoter in the ER-negative breast cancer cells was evaluated by methylation specific PCR (MSP) and genomic sequencing. The expression of ER and progesterone receptor (PR) mRNA as well as the production of ER protein were detected by RT-PCR and Western blot method, respectively. MTI assay was used to examine the function of re-expressed ER protein.The ER gene promoter was highly methylated, while ER mRNA and ER protein were not expressed in the ER-negative breast cell line MDA-MB-231. The ER-negative breast cells treated with demethylating agent 5 -aza-2'-deoxycytidine (5-AZA-2'-deoxyC) restored the expression of ER mRNA and ER protein. Expression of the endogenous ER-responsive PR gene was activated and the methylation of ER gene was simultaneously decreased. After MDA-MB-231 was treated with 5-AZA-2'-deoxyC, the protein of ER was re-expressed and the growth of cells treated with tamoxifen were inhibited significantly (P0.05).inactivation of ER gene has a close relationship with the abnormal methylation of ER gene promoter. 5-AZA-2'-deoxyC may effectively cause demethylation and restore functional expression of ER silenced by aberrant hypermethylation. The result may offer a new measure and theory for breast cancer patients with ER-negative expression to receive endocrine therapies.