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Germanium-doped silica films were prepared by magnetron cosputtering and postannealing. The photoluminescence properties and their dependence on the Ge contents and annealing temperature were investigated. Our experiments indicate that the observed light emission originates from the neutral oxygen vacancy defects. The substructures in the luminescence bands of the films were found to result from multiple-beam interferences of the emission in the optical cavity formed by the transparent films. [ABSTRACT FROM AUTHOR]

First-principles calculations on the structural, electronic, and magnetic properties of the distorted perovskite SeNiO3 show that the G-type antiferromagnetic structure with the insulating ground state that has about 3.77 eV band gap is more stable than other possible configurations. The hybridizations of Se–O and Ni–O cause the spin magnetic moment to reduce to 1.86μB in comparison with 2μB of the Ni2+3d8 configuration. The similarity between the orbital-resolved densities of Ni 3d states is attributed to the unusual structure of SeNiO3 and the covalent bond of the Ni–O. [ABSTRACT FROM AUTHOR]

First-principles calculations on the structural, electronic, and magnetic properties of the distorted perovskite SeNiO3 show that the G-type antiferromagnetic structure with the insulating ground state that has about 3.77 eV band gap is more stable than other possible configurations. The hybridizations of Se–O and Ni–O cause the spin magnetic moment to reduce to 1.86μB in comparison with 2μB of the Ni2+3d8 configuration. The similarity between the orbital-resolved densities of Ni 3d states is attributed to the unusual structure of SeNiO3 and the covalent bond of the Ni–O. [ABSTRACT FROM AUTHOR]

First-principles calculation is used to study the pressure-induced metal-insulator transition in BiNiO3. It is found that the G-antiferromagnetic insulator triclinic phase in BiNiO3 transforms to the ferromagnetic half-metallic orthorhombic phase with a volume collapse of 6.2% when the applied pressure is 3.46 GPa. The interaction between neighbor Ni atoms creates the energy band gap of 1.96 eV in the majority density of states. The pressure suppresses the charge disproportion of Bi. The strong hybridizations of Ni–O and Bi–O lead to the decrease of the spin magnetic moment with 1.74μB compared with the Ni3+ with d7 configuration 3μB. [ABSTRACT FROM AUTHOR]

First-principles calculation is used to study the pressure-induced metal-insulator transition in BiNiO3. It is found that the G-antiferromagnetic insulator triclinic phase in BiNiO3 transforms to the ferromagnetic half-metallic orthorhombic phase with a volume collapse of 6.2% when the applied pressure is 3.46 GPa. The interaction between neighbor Ni atoms creates the energy band gap of 1.96 eV in the majority density of states. The pressure suppresses the charge disproportion of Bi. The strong hybridizations of Ni–O and Bi–O lead to the decrease of the spin magnetic moment with 1.74μB compared with the Ni3+ with d7 configuration 3μB. [ABSTRACT FROM AUTHOR]

First-principles calculations on the electronic and magnetic properties of BiNiO3 reveal that the G-type antiferromagnetic structure with the insulating ground state is more stable than other possible configurations. The hybridization of Ni–O and Bi–O leads to the reduction of the spin magnetic moment to 1.67μB in comparison with the Ni2+ d8 configuration of 2μB. The band gap of the antiferromagnetic insulating ground state is predicted to be 0.68 eV. The antiferromagnetic interaction induces the localized spins to be S=1 in the G-antiferromagnetic structure of BiNiO3. [ABSTRACT FROM AUTHOR]

First-principles calculations on the electronic and magnetic properties of BiNiO3 reveal that the G-type antiferromagnetic structure with the insulating ground state is more stable than other possible configurations. The hybridization of Ni–O and Bi–O leads to the reduction of the spin magnetic moment to 1.67μB in comparison with the Ni2+ d8 configuration of 2μB. The band gap of the antiferromagnetic insulating ground state is predicted to be 0.68 eV. The antiferromagnetic interaction induces the localized spins to be S=1 in the G-antiferromagnetic structure of BiNiO3. [ABSTRACT FROM AUTHOR]

Objective: To investigate the value of stereotactic biopsy in the accurate diagnosis of lesions in the brain stem and deep brain. Methods: A total of 29 consecutive patients who underwent stereotactic biopsy of brainstem and deep brain lesions between May 2012 and January 2018 were retrospectively reviewed. The Cosman-Roberts-Wells (CRW) stereotactic frame was installed under local anesthesia. Thin-layer CT and MRI scanning were performed. Target coordinates were calculated by inputting CT-MRI data into the radionics surgical planning system. The individualized puncture path was designed according to the location of the lesions and the characteristics of the image. Target distributions were as follows: 12 cases of midbrain or pons, 2 cases of internal capsule, 3 cases of thalamus, 12 cases of basal ganglia. The biopsy samples were used for further pathological and/or genetic diagnosis. Results: Twenty-eight of the 29 cases (96.6%) were diagnosed accurately by histopathology and genomic examination following stereotactic biopsy. Pathological results were as follows: 8 cases of lymphoma, 7 cases of glioma, 4 cases of demyelination, 2 cases of germ cell tumor, 2 cases of metastatic tumor, 1 cases of cerebral sparganosis, 1 case of tuberculous granuloma, 1 case of hereditary prion disease, 1 case of glial hyperplasia, 1 case of leukemia. The accurate diagnosis of one case required a combination of histopathology and genomic examination. Undefined diagnosis was still made in 1 cases (3.45%) after biopsy. After biopsy, there were 2 cases (6.9%) with symptomatic slight hemorrhage, 1 case (3.45%) with symptomatic severe hemorrhage, and 1 cass (3.45%) with permanent neurological dysfunction. No one died because of surgery or surgical complications. Conclusions: Stereotactic biopsy is fast, safe and minimally invasive. It is an ideal strategy for accurate diagnosis of lesions in brain stem and deep brain.

Sewage sludge ash has been widely applied to cementitious materials. In this study, in order to determine effects of nano-SiO(2) additives on properties of sludge/fly ash mortar, different amounts of nano-SiO(2) were added to sludge/fly ash mortar specimens to investigate their physical properties and micro-structures. A water-binding ratio of 0.7 was assigned to the mix. Substitution amounts of 0%, 10%, 20%, and 30% of sludge/fly ash (1:1 ratio) were proposed. Moreover, 0%, 1%, 2%, and 3% of nano-SiO(2) was added to the mix. Tests, including SEM and compressive strength, were carried out on mortar specimens cured at 3, 7, and 28 days. Results showed that sludge/fly ash can make the crystals of cement hydration product finer. Moreover, crystals increased after nano-SiO(2) was added. Hence, nano-SiO(2) can improve the effects of sludge/fly ash on the hydration of mortar. Further, due to the low pozzolanic reaction active index of sludge ash, early compressive strengths of sludge/fly ash mortar were decreased. Yet, nano-SiO(2) could help produce hydration crystals, which implies that the addition of nano-SiO(2) to mortar can improve the influence of sludge/fly ash on the development of the early strength of the mortar.

A study on iron-deficiency anemia (IDA) in adolescence was conducted among 478 teen-age students in Shanghai. The study indicated that the intake of nutrients among the students was generally insufficient. The lack of protein, calcium, Vitamin A, Vitamin B1, and Vitamin B2 was more serious. The morbidities of IDA among male and female students were 15.8 and 32.6%, respectively, higher in the female group (P less than 0.01). The iron-deficiency sufferers among male and female students were 46.8 and 61.8%, respectively, also higher in the female group (P less than 0.01). The causes of IDA were analyzed by the method of stepwise regression. In a study of the effect of IDA on intelligence and physical development in adolescents, we found that there was no significant effect of IDA on intelligence quotient (IQ) and school performance. However, the speed and endurance capabilities of students of both sexes were correlated directly with hemoglobin level. In female students, the speed capability was correlated directly with the serum ferritin content. On the basis of these findings, a special 3-month school lunch program was initiated. The results indicate that a comprehensive, rational, and balanced diet is beneficial to hemoglobin, free erythrocyte porphyrin, and serum ferritin contents and improves adolescent development.