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This paper proposes a new robust LM test for spatial lag model that is set when there are unknown error distribution, model misspecification and changes of spatial layout. We analyze the asymptotic properties uing Bootstrap and Monte Carlo methods which are found to be superior to the LM method. Moreover, we also find that Bootstrap is most efficaious. It is more reliable to use combined Bootstrap and our proposed testing statistic when sample size is small. It is also more reliable to use our proposed testing statistic when "Group" in spatial layouts is contigous. [ABSTRACT FROM AUTHOR]

A variety of hematite microstructures are synthesized through oxalic acid-assisted thermal treatment of iron films sputtered onto glass substrates. Petal-like α-Fe2O3 nanoslices and honeycomb-like α-Fe2O3 particles of micrometer sizes are obtained after annealing at 500°C but with different rates of heating to the final annealing temperature. Structures and morphologies of the samples are studied by means of x-ray diffraction, scanning electron microscopy and atomic force microscopy. These structures are believed to be formed during the period of increasing temperature to the final annealing temperature. Superconducting-quantum-interference-device magnetometer measurements show room-temperature ferromagnetism in these samples. [ABSTRACT FROM AUTHOR]

Abstract Objectives Our study aimed to investigate the prevalence of cognitive impairment(CI) and the associated risk factors among elderly people in Shanghai urban area, China. Methods A population-based survey was conducted among people aged 55 years or older in urban areas of Shanghai. Face-to-face interviews were carried out to collect information including demographic characteristics, medical history, and medication use, etc. The validated Chinese version of the Mini-Mental State Examination(MMSE) was used to screen subjects with CI, and the criteria of CI were adjusted for education levels. Results A total of 3,176 home-living residents (≥55 years old) were included in the study. Among them, 266 people (102 men and 164 women) were identified as cognition impaired, with a prevalence of 8.38% (266/3,176, 95% CI: (8.26, 8.49)) for both genders, 9.21% (102/1,107,95% CI: (9.18, 9.33)) for men and 7.93% (164/2,069, 95% CI: (7.80, 8.09)) for women, respectively. Furthermore, we found that several significant risk factors, including social factors(education, number of children, marriage status, and family structure), physiological factors (age, blood glucose level, and obesity), factors on living styles(physical exercise, diet & chronic diseases), and genetic factor(ApoE), associated with CI onset. Conclusions This study confirms the high prevalence of CI among the elderly population in the Shanghai urban in China, similar to previous epidemiologic studies in Western countries. The putative risk factors associated with CI merit further investigated.

Abstract Background Before 1986, scrub typhus was only found endemic in southern China. Because human infections typically occur in the summer, it is called "summer type". During the autumn-winter period of 1986, a new type of scrub typhus was identified in Shandong and northern Jiangsu province of northern China. This newly recognized scrub typhus was subsequently reported in many areas of northern China and was then called "autumn-winter type". However, clinical characteristics of associated cases have not been reported. Methods From 1995 to 2006, all suspected scrub typhus cases in five township hospitals of Feixian county, Shandong province were enrolled. Indirect immunofluorescent assay (IFA) was used as confirmatory serodiagnosis test. Polymerase chain reaction (PCR) connected with restriction fragment length polymorphism (RFLP) and sequence analyses were used for genotyping of O. tsutsugamushi DNAs. Clinical symptoms and demography of confirmed cases were analyzed. Results A total of 480 scrub typhus cases were confirmed. The cases occurred every year exclusively between September and December with a peak occurrence in October. The case numbers were relatively higher in 1995, 1996, 1997, and 2000 than in other years. 57.9% of cases were in the group aged 21–50. More cases occurred in male (56%) than in female (44%). The predominant occupational group of the cases was farmers (85.0%). Farm work was reported the primary exposure to infection in 67.7% of cases. Fever, rash, and eschar were observed in 100.0%, 90.4%, and 88.5% of cases, respectively. Eschars formed frequently on or around umbilicus, abdomen areas, and front and back of waist (34.1%) in both genders. Normal results were observed in 88.7% (WBC counts), 84.5% (PLT counts), and 89.7% (RBC counts) of cases, respectively. Observations from the five hospitals were compared and no significant differences were found. Conclusion The autumn-winter type scrub typhus in northern China occurred exclusively from September to December with a peak occurrence in October, which was different from the summer type in southern China. In comparison with the summer type, complications associated with autumn-winter type scrub typhus were less severe, and abnormalities of routine hematological parameters were less obvious.

A variety of hematite microstructures are synthesized through oxalic acid-assisted thermal treatment of iron films sputtered onto glass substrates. Petal-like α-Fe2O3 nanoslices and honeycomb-like α-Fe2O3 particles of micrometer sizes are obtained after annealing at 500°C but with different rates of heating to the final annealing temperature. Structures and morphologies of the samples are studied by means of x-ray diffraction, scanning electron microscopy and atomic force microscopy. These structures are believed to be formed during the period of increasing temperature to the final annealing temperature. Superconducting-quantum-interference-device magnetometer measurements show room-temperature ferromagnetism in these samples. [ABSTRACT FROM AUTHOR]

Abstract: Multiferroic thin films with the general formula TiO2/BiFe1−x Mn x O3 (x=0.00, 0.05, 0.10 and 0.15) (TiO2/BFMO) were synthesized on Au/Ti/SiO2/Si substrates using a chemical solution deposition (CSD) method assisted with magnetron sputtering. X-ray diffraction analysis shows the thin films contained perovskite structures with random orientations. Compared with BFMO films, the leakage current density of the TiO2/BFMO thin films was found to be lower by nearly two orders of magnitude, and the remnant polarizations were increased by nearly ten times. The enhanced ferroelectric properties may be attributed to the lower leakage current caused by the introduction of the TiO2 layer. The J–E characteristics indicated that the main conduction mechanism for the TiO2/BFMO thin film was trap-free Ohmic conduction over a wide range of electric fields (0–500kV/cm). In addition, ferromagnetism was observed in the Mn doped BFO thin films at room temperature. The origin of ferromagnetism is related to the competition between distortion of structure and decrease of grain size and decreasing net magnetic moment in films due to Mn doping. [Copyright &y& Elsevier]

New materials for achieving direct electric field control of ferromagnetism and resistance behavior are highly desirable in the development of multifunctional data storage devices. In this paper, HfO 2 nanoporous films have been fabricated on porous anodic alumina (PAA) substrates by DC-reactive magnetron sputtering. Electrically induced resistive switching (RS) and modulated room temperature ferromagnetism are simultaneously found in a Ag/HfO 2 /PAA/Al (Ag/HP/Al) heterostructure. The switching mechanism between low resistance state and high resistance state is generally attributed to the formation/rupture of conductive filaments which may consist of oxygen vacancies. The combination of the electric field control of magnetization change and RS makes HP films possible for the multifunctional data storage media materials.