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Samples of Ni0.6Zn0.3Co0.1NdxFe2-xO4 (0.00 ≤ x ≤ 0.10) ferrites were synthesized by the sol-gel auto-combustion method and microwave sintering technology. The effects of Nd substitution on the crystal structure, magnetic, and electrical properties have been investigated. The XRD results showed that the main phase of sintered samples was a standard spinel structure. When x > 0.02, the second phase appeared in the sintered samples, which led to the phenomenon that the lattice constant of the sample increased and then decreased. Overall, the saturation magnetization of the samples showed a downward trend, and the value of coercivity increased with the amount of substitution. In terms of electrical performance, the dielectric constant of the samples showed an overall increasing trend with the amount of substitution after a sharp drop in the low frequency band and tended to be stable in the high frequency band. At x = 0.02, the ferrite sample exhibited the lowest dielectric constant (e', 41.63), the highest dc resistivity (ρ, 4.973 × 106 Ω∙m), relatively small coercivity (Hc, 20.878 Oe) and relatively high saturation magnetization (Ms, 79.214 emu/g).

Ni0.6Zn0.4Co0.2Fe1.8O4 ferrites doped with x wt.% K0.5Na0.5NbO3 (0.00≤x≤1.00) were successfully prepared by solid-state reaction method. The lattice parameters a decreased and the diffraction peak of (311) shifted to higher angle with the increase of K0.5Na0.5NbO3 (KNN) content. The grain size D initially increased to 3.12 μm (x = 0.50) and then reduced to 2.66 μm (x=1.00). The study also showed the addition of KNN effectively improved magnetic and electrical properties of NiZnCo ferrites. The saturation magnetization Ms decreased from 60.59 to 46.11 emu/g and the coercivity Hc overall showed a decreasing trend from 84.64–67.00 Oe. The dielectric constant e´ of prepared samples increased when x≤0.75, then decreased when x>0.75, and all prepared samples had low loss tangent tanδ at high frequency. In addition, all samples exhibited high resistivity ρ and activation energy Eρ.

This study aimed to identify mechanisms of drug resistance to the combination of vemurafenib, irinotecan, and cetuximab (VIC) in BRAFForty-one patients with BRAFBRAF mutant in baseline plasma and its dynamics are significantly associated with VIC-related response, and concurrent RNF43 mutation significantly sensitises tumour to VIC treatment. VIC resistance frequently involves genes in PI3K, MAPK pathway, and several novel resistance mechanisms such as TGFBR2 and SMAD4 mutations, and copy-number gains in PTK2, MYC, and GATA6 have been identified. We also firstly describe acquired altered genes in DNA damaging repair pathway, occurring in 33 % of patients after VIC treatment, and particularly, patients with this pre-treatment resistance subclones developed inferior responses, along with higher tumour mutation burden both at baseline and progression plasma.Analysis of ctDNA can provide novel insights into molecular resistance mechanisms to VIC in BRAF

HfO2 doped NiZnCo bulk ferrites, Ni0.5Zn0.3Co0.2Fe2O4 with different HfO2 dopant content (0 ≤ x ≤ 0.1 wt%), were fabricated by the solid states reaction method. We investigated the influence of HfO2 doping on structure and electromagnetic properties. The XRD pattern shows that as the doping of HfO2 increases, the lattice parameter decreases and the X-ray density increases. There is an extra peak in each sample due to generation of NiCo2O4 impurity phase. The SEM images demonstrate the grain size slightly decreases with increasing HfO2 content. As the amount of HfO2 doping increases, the saturation magnetization increases linearly and the coercivity decreases. The polarization of all ferrite samples is due to the fact that the electronic hopping frequency between Fe2+ and Fe3+ ions can't keep up with external applied frequency. As the amount of HfO2 doping increases, the dielectric constant increases when x

NiZnCe ferrite, Ni0.4Zn0.6−xCexFe2O4 (0 ≤ x ≤ 0.20), were prepared by the sol-gel self-spreading process combing with the solid reaction process. The crystal structure and physical properties of NiZnCe ferrite with different amount of Ce substitution have been studied. The lattice parameter and density rise and the grain size is decreasing with Ce substitution increasing because the ionic radius of Ce3+ ion is much bigger than that of Zn2+ ions, and the atomic weight of Ce3+ ions is heavier than Zn2+ ions. Ms initially increases with increasing amount of Ce substitution because of the increase of density and reduction of porosity, then it decreases when Ce substitution excesses 0.15 which contributes to the increase of the net magnetic moment in tetrahedral site and porosity and the apparence of CeO2 phase. Hc monotonously decreases with Ce substitution increasing due to the mono-domain structure of grains. The initial permeability initially increases at room temperature with the Ce substitution content increasing and has the maximum when the replacement content is 0.15. But it sharply drops when the amount of Ce replacement is 0.20 because the porosity increasing and impurity phase appearance. The Curie temperature has been greatly improved with Ce substitution due to the enhancements of A-B superexchange interactions. The dc resistivity gradually decreases at room temperature due to the fact that Ce substitution reduces the activation energy, and it obeys an exponential decay with the temperature increasing.

Nucleic acids generally reside in cellular aqueous solutions with mixed divalent/monovalent ions, and the competitive binding of divalent and monovalent ions is critical to the structures of nucleic acids because of their polyanionic nature. In this work, we first proposed a general and effective method for simulating a nucleic acid in mixed divalent/monovalent ion solutions with desired bulk ion concentrations via molecular dynamics (MD) simulations and investigated the competitive binding of Mg2+/Na+ ions to various nucleic acids by all-atom MD simulations. The extensive MD-based examinations show that single MD simulations conducted using the proposed method can yield desired bulk divalent/monovalent ion concentrations for various nucleic acids, including RNA tertiary structures. Our comprehensive analyses show that the global binding of Mg2+/Na+ to a nucleic acid is mainly dependent on its structure compactness, as well as Mg2+/Na+ concentrations, rather than the specific structure of the nucleic acid. Specifically, the relative global binding of Mg2+ over Na+ is stronger for a nucleic acid with higher effective surface charge density and higher relative Mg2+/Na+ concentrations. Furthermore, the local binding of Mg2+/Na+ to a phosphate of a nucleic acid mainly depends on the local phosphate density in addition to Mg2+/Na+ concentrations.

Ni0.55Zn0.3Co0.15GdxFe2-xO4 (x = 0, 0.05, 0.10, 0.15, 0.20) ferrite materials with spinel structure were successfully synthesized by sol–gel self-propagation and microwave sintering technique. The structure and electromagnetic properties of NiZnCo ferrite with Gd substitution are systematically studied. The results show that the substitution of Gd3+ for Fe3+ at the B site changes the electromagnetic properties of NiZnCo ferrite. Among them, the resonant frequency increased from 637 MHz (x = 0.00) to more than 1.5 GHz (x = 0.20), which is 2.5 times higher than that of pure NiZnCo ferrite. Moreover, when the doping amount x = 0.05, the dielectric constant of ferrite is the lowest (e′, 37.735), the DC resistivity is the highest (ρ, 3.64 × 106 Ω·m), and the dielectric loss is the lowest (tanδ, 3.03). In general, the substitution of Gd can make NiZnCo ferrite obtain excellent electromagnetic properties, which provides a reference for high-frequency microwave device materials.

In the past two decades, numerous studies on dioxin concentrations in breast milk have been conducted in China. However, information concerning dioxin concentrations in breast milk from women living in e-waste recycling sites remains limited. Thus, this study aimed to evaluate health risk owing dioxin intake in e-waste recycling areas in China. In 2015, 42 mothers were recruited from an e-waste recycling site, and the same number of mothers were recruited from a reference site. We collected 10-mL breast milk samples from each participant. Breast milk concentrations of polychlorinated dibenzo-p-dioxins (PCDDs)/polychlorinated dibenzofurans (PCDFs) were significantly higher in the exposed group than in the reference group. The total toxic equivalents (TEQ) of PCDDs/DFs were 9.68 pg/g lipid in the exposed group, a value two times higher than those in the reference group (4.18 pg/g lipid). The estimated daily intake (EDI) of PCDD/DFs was calculated to assess the risk of dioxins through breastfeeding. The infant EDI level was two times higher in the exposed group (54.21 pg TEQ/kg body wt/day) than in the reference group (23.41 pg TEQ/kg body wt/day). Our findings suggest that mothers and their breastfeeding infants living in an e-waste recycling site were exposed to higher dioxin concentrations than those living in a reference site.

A full understanding of RNA-mediated biology would require the knowledge of three-dimensional (3D) structures, structural flexibility and stability of RNAs. To predict RNA 3D structures and stability, we have previously proposed a three-bead coarse-grained predictive model with implicit salt/solvent potentials. In this study, we will further develop the model by improving the implicit-salt electrostatic potential and involving a sequence-dependent coaxial stacking potential to enable the model to simulate RNA 3D structure folding in divalent/monovalent ion solutions. As compared with the experimental data, the present model can predict 3D structures of RNA hairpins with bulge/internal loops (, 24 pages,8 figures

Primary small cell carcinoma of the esophagus (SCCE) is characterized as highly aggressive with a poor prognosis. To identify potential prognostic factors and to assess the role of surgical procedures, chemotherapy, and radiotherapy for SCCE, we retrospectively analyzed patients with SCCE from three large institutions in China.All of the SCCE patients between 1998 and 2012 were identified from three clinical databases of the Sun Yat-Sen University Cancer Center, Peking Union Cancer Hospital and Shantou Cancer Hospital. Potential prognostic factors were analyzed with univariate analysis and a Cox regression model. Subgroup analysis based on the 2002 American Joint Committee on Cancer staging system for esophageal cancer was applied to examine the effect of treatment on survival.In patients with stage I/II SCCE, 85% underwent operations and showed improved survival (median survival time [MST] 29 vs 17.4 months, p = 0.082). However, chemotherapy did not further improve survival. In patients with stage IIB/III SCCE, chemotherapy, instead of operation, improved survival (MST 13.0 vs 6.1 months, p = 0.003), and radiotherapy resulted in improved survival. In stage IV patients, chemotherapy improved survival (MST 12.5 vs 4.0 months, p0.001), and chemotherapy combined with radiotherapy was superior to chemotherapy alone (MST 13.2 vs 8.9 months, p = 0.014).Surgical procedures alone can be recommended for stage I/IIA patients. In patients with stage IIB disease or above, chemotherapy should be the main treatment approach, and chemotherapy combined with radiotherapy tended to improve survival.

The abundance and distribution of antibiotics and antibiotic resistance genes (ARGs) in soils from six parks using reclaimed water in Beijing, China, were characterized. Three classes of commonly used antibiotics (tetracycles, quinolones, and sulfonamides) were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The highest concentrations of tetracyclines and quinolones were 145.2 mu g kg(-1) and 79.2 mu g kg(-1), respectively. Detected tetG, tetW, sulI, and sulII genes were quantified by quantitative PCR. ARGs exhibited various abundances for different park soils. The integrase gene (intI1) as an indicator of horizontal gene transfer potential was also detected in high abundance, and had significant positive correlation with tetG, sulI, and sulII genes, suggesting that intI1 may be involved in ARGs dissemination. Both sulII and intI1 clones had high homology with some classes of pathogenic bacteria, such as Klebsiella oxytoca, Acinetobacter baumannii, Shigella flexneri, which could trigger potential public health concern. (C) 2013 Elsevier Ltd. All rights reserved.

Ions are critical to the structure and stability of polyelectrolytes such as nucleic acids. In this work, we systematically calculated the potentials of mean force between two like-charged nanoparticles in salt solutions by Monte Carlo simulations. The pseudo-spring method is employed to calculate the potential of mean force and compared systematically with the inversed-Boltzmann method. An effective attraction is predicted between two like-charged nanoparticles in divalent/trivalent salt solution and such attraction becomes weakened at very high salt concentration. Our analysis reveals that for the system, the configuration of ion-bridging nanoparticles is responsible for the attraction, and the invasion of anions into the inter-nanoparticles region at high salt concentration would induce attraction weakening rather than the charge inversion effect. The present method would be useful for calculating effective interactions during nucleic acid folding., Comment: 23 pages, 8 figures, Supporting Material

Objective The aim of this study was to analyze whether pathologic complete response (PCR) to neoadjuvant chemotherapy (NAC) affected long-term survival in advanced head and neck squamous cell carcinoma (HNSCC) patients. Materials All patients with advanced HNSCC were previously untreated and underwent NAC followed by surgery. The 5-year overall survival, disease-free survival, local control rate, and reasons for treatment failure were analyzed. Results A total of 101 cases were included, and the response rate to NAC was 67.3%, including 17 patients (16.8%) who achieved PCR. The 5-year overall survival (OS) of the PCR group (82.4%; histologically complete response group [HCG]) was higher than that of the pathologic incomplete responder group (45.4%; histologically incomplete response group [HICG]) (P = 0.045). No statistically significant difference was noted between the two groups in terms of local recurrence and nodal recurrence, but the local control rate in HCG (88.2%) was higher than that in HICG (62.7%) (P = 0.034). Conclusions Achieving PCR could improve locoregional control and long-term survival in patients with advanced HNSCC.

Summary Objectives Platinum-based chemotherapy is the recognized first-line treatment for metastatic nasopharyngeal carcinoma (NPC). However there is no standard second-line treatment. This study was designed to evaluate the efficacy and safety of a gemcitabine and vinorelbine combination (GV) in patients with metastatic NPC previously treated with platinum-based chemotherapy. Methods A total of 61 patients with metastatic NPC after prior platinum-based chemotherapy were enrolled. Gemcitabine (1000 mg/m2) and vinorelbine (25 mg/m2) were administered intravenously on Day 1 and Day 8 every 3 weeks. Results In this study, the overall response rate was 37.7% (95% CI, 25.5–49.9%) one complete response (1.6%) and 22 partial responses (36.1%). The median progression-free survival was 5.2 months (95% CI, 3.4–7.0 months) and the median overall survival was 14.1 months (95% CI, 11.1–17.1 months). Grade 3/4 toxicity including leucopenia (19.7%), neutropenia (18%), anemia (4.9%) and thrombocytopenia (6.5%) were tolerable. Univariate and multivariate analyses indicated age and salvage treatment after failure of GV treatment were independently significant prognostic factors. Conclusion Our preliminary result shows gemcitabine and vinorelbine combination is effective and safe for the patients with advanced NPC pretreated with platinum-based chemotherapy. Further clinical study is warranted.

An architecture featured in quality of service (QoS) online self-adjusted measurement and control for wireless sensor networks (WSN) is proposed in this paper. Unlike traditional end to end (E2E) QoS definition, many new characteristics are presented in WSN, especially data-centric and application driven. Based on exploration of WSN QoS definition and typical traffic model, we design a dynamic QoS guarantees platform, which achieves online protocol self-adjustment to get optimization performance. The architecture is verified by a practical system designed for environment monitoring.

Purpose To describe the prevalence and associations of retinopathy in a population-based nondiabetic sample of rural Chinese. Design Population-based cross-sectional study. Participants We included 6830 Han Chinese aged ≥30 years from 13 villages of Yongnian County, Handan City, Hebei Province, China. Methods All participants underwent a standardized interview and extensive examinations including retinal photography, measurement of blood pressure (BP) and fasting plasma glucose (FPG). Diabetes mellitus was defined as either FPG ≥ 7.0 mmol/l, use of diabetic medication or a physician diagnosis of diabetes. Photographic grading of retinopathy followed the modified Early Treatment Diabetic Retinopathy Study classification system. Logistic regression models were used to assess associations of retinopathy. Main Outcome Measures Any retinopathy. Results The prevalence of retinopathy among participants without diabetes was 13.6% (95% confidence interval [CI], 12.6–14.6%). The age and gender standardized prevalence of retinopathy in the Chinese adult population (aged 30+ years) without diabetes was estimated to be 12.1% (95% CI 11.1–12.9%). Independent risk factors associated with retinopathy were age (odds ratio [OR], 1.02 ; 95% CI 1.01–1.03 per year increase), male gender (male vs. female, OR 1.27; 95% CI 1.08–1.49), higher FPG (OR 1.30; 95% CI 1.11–1.53 per mmol/l increase), higher systolic BP (OR 1.15; 95% CI 1.05–1.27 per 10 mmHg increase) and higher diastolic BP (OR 1.16; 95% CI 1.09–1.22 per 10 mmHg increase). Conclusions Retinopathy was common among rural Chinese adults without diabetes. Its association with FPG and BP suggests that early microvascular damage is occurring at "high normal" levels of blood glucose and BP. Financial Disclosure(s) The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Purpose To describe the prevalence and causes of low vision and blindness in a rural population in Northern China. Design Population-based, cross-sectional study. Participants A study of 6830 Han Chinese aged 30 years and older was conducted between October 2006 and October 2007 in rural Yongnian County in Handan, Northern China. Methods Clustered samples of adults aged 30 years or more residing in 13 residential villages were selected randomly and were invited to participate the Handan Eye Study. Participants underwent a comprehensive eye examination, including standardized visual acuity (VA) tests using logarithm of the minimum angle resolution charts. Prevalence was age- and gender-standardized to the 2000 China Census. Main Outcome Measures Low vision was defined as VA Results Six thousand eight hundred thirty (90.4%) of 7577 eligible individuals participated in the study, and 6799 (89.7%) had VA data available. Population-weighted prevalence of presenting bilateral blindness was 0.6% and bilateral low vision was 4.7% for persons 30 years of age and older. Based on best-corrected visual acuity (BCVA), the corresponding prevalence of blindness was 0.5% and that of low vision was 1.0%. Blindness and low vision were strongly age related ( P Conclusions A higher prevalence of blindness and low vision was seen in this rural Chinese sample than has been reported from urban Chinese populations. The estimated numbers with BCVA-defined low vision and blindness in 2020, based on best-corrected vision in rural Chinese adults aged 30 years or more, is expected to be 12.4 million and 2.9 million, respectively. Predominant causes of low vision and blindness in China are treatable. Financial Disclosure(s) The authors have no proprietary or commercial interest in any materials discussed in this article.