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Abstract: LiFePO4/C and LiFe1−x Ni x PO4/C (x =0, 0.02, 0.04, and 0.06) composites were prepared using solid-state reaction. The as-prepared composites were characterized by using X-ray diffraction, charge–discharge cycling, cyclic voltammograms, Raman spectroscopy, field emission scanning electron microscopy, high-resolution transmission electron microscopy, and other techniques. The experimental results show that all as-prepared composites have a single phase of orthorhombic olivine-type structure with the Pnmb space group. The as-prepared LiFe1−x Ni x PO4/C composites exhibit high capacities and good cycling performance; e.g., the LiFe0.98Ni0.02PO4/C composite delivers 142 and 138mAhg−1 at the 0.1C rate for the first and fifth cycles, respectively. Such composites also show good rate capabilities; e.g., when discharged at the 2C rate the LiFe0.98Ni0.02PO4/C composite delivers an initial capacity of 121mAhg−1, 85% of the discharge capacity at the 0.1C rate. The reason why the LiFe1−x Ni x PO4/C composites have better electrochemical performance compared to the LiFePO4/C composites is because nickel doping enhances the Ptabilizes the structure, and thus the charge-transfer resistance and cathode particle resistance of the composites are decreased. [Copyright &y& Elsevier]

Objective: To understand the distribution of esophageal squamous cell cancer and precursor lesions in high-risk areas of China, and to provide evidence for determining the reference ranges of detection rates in high-risk areas., Methods: Endoscopy with Lugol's iodine staining was performed on 15 709 local residents aged 40 to 69 years old in Linzhou of Henan province and Feicheng of Shandong province from 2005-2009. 35 cases without accurate pathology diagnosis and 11 cases with vital disease before screening were excluded. 15 663 subjects were enrolled in this study. Compliance was calculated by the percentage of the people who had endoscopic screening among the target population. Chi-square test and trend chi-square test were used to compare the distribution differences in age, gender and areas of esophageal squamous cell cancer and precancer. 95% CI of the detection rates was then employed to represent the reference ranges of esophageal squamous cell cancer and precursor lesions., Results: The compliance rate of screening endoscopy of this study was 49.36% (15 709/31 826) of all, and female's compliance (54.05%, 8 447/15 628) was much higher than that of male (44.83%, 7 262/16 198) (χ(2) = 88.14, P < 0.001). The detection rates of basal cell hyperplasia, low grade intraepithelial neoplasia, high grade intraepithelial neoplasia and esophageal squamous cell cancer of males were 4.17% (302/7 246), 17.22% (1 248/7 246), 1.67% (121/7 246), 0.83% (60/7 246), and were higher than that of females (3.45% (290/8 417), 14.82% (1 247/8 417), 1.41% (119/8 417), 0.48% (40/8 417), respectively). Except for high-grade intraepithelial neoplasia, the detection rates of male were higher than that of female (P values were 0.018, < 0.001, 0.960, 0.006). The detection rates of all grades of precursor lesions increased with age rising (all P values < 0.001), among which the detection rates of the mentioned four lesions for 40-44 years old were 2.69% (94/3 500), 8.11% (284/3 500), 0.40% (14/3 500), 0.14% (5/3 500), and that of 65-69 years old were 5.46% (46/843), 23.25% (196/843), 3.68% (31/843), 2.14% (18/843). The proportion of esophageal precursor lesion of Linzhou were higher than that of Feicheng observably except for esophageal squamous cell cancer (P values were < 0.001, < 0.001, < 0.001, 0.437). The detection rates of the four lesions of Linzhou and Feicheng were 4.90% (504/10 287), 17.37% (1 787/10 287), 1.79% (184/1 0287), 0.60% (62/10 287) and 1.64% (88/5 376), 13.17% (708/5 376), 1.04% (56/5 376), 0.71% (38/5 376). The 95% CI of detection rates of various lesions were, 3.78% (3.48%-4.08%) for basal cell hyperplasia, 15.93% (15.37%-16.50%) for low-grade intraepithelial neoplasia, 12.31% (11.79%-12.82%) for mild dysplasia and 3.62% (3.33%-3.91%) for moderate hyperplasia, 1.53% (1.34%-1.72%) for high-grade intraepithelial neoplasia and 0.64% (0.51%-0.76%) for esophageal squamous cell cancer, respectively., Conclusion: Up to 21.88% residents that were asymptomatic were suffered from esophageal squamous cancer or precursor lesions in high-risk areas in China. The distribution of esophageal squamous cell cancer and precursor lesions was closely related to the gender and the age, which suggested that males were supposed to be paid more attention to.

Objective: To estimate the cost-effectiveness of esophageal cancer endoscopic screening once-in-a-lifetime and to predict the optimal screening age for people in high-risk areas of rural China., Methods: A Markov model was constructed to predict and compare the effect of four esophageal cancer endoscopic screening modalities which varied with different screening ages. Long-term epidemiological effectiveness and cost-effectiveness were predicted by simulation of the model., Results: Compared with the control group, strategies starting at 40, 45, 50 and 55 year-old had saved life-years of 629.51, 769.88, 738.98 and 533.21 years per 100 000 people, respectively, of which the strategy starting at 45 year-old saved the maximum life years. All strategies were cost-effective and starting at 40 year-old cost the most per life-year saved. Among all alternatives, strategies starting age at 45 year-old and 50 year-old were incremental cost-effective, and the incremental cost-effective ratios were 34 962.87 and 3 346.43 RMB per life year saved, respectively., Conclusions: The strategy starting at 40 year-old implemented at present and other strategies were cost-effective in high-risk areas of rural China. However, the 45-year-old group is more aligned with the principle of cost-effectiveness. Considering the cost-effectiveness of different strategies and social economic status, 45 year-old is regarded as the optimal starting age of esophageal cancer once-in-a-lifetime endoscopic screening and is recommended in areas lacking health resources. The strategy of starting age at 40 year-old which could obtain better screening effects would be preferable in wealthy regions.