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Ce4+ and Zn2+ co-doped barium hexaferrites (BFO) have been synthesized via a citrate-nitrate autocombustion route. Phase purity has been confirmed by high resolution (HR) powder X-ray diffraction analysis. Rietveld refinement on HR-XRD data has been carried out to reveal the crystal structure, bond angles and bond lengths. High-resolution scanning electron microscope (HR-SEM) has been used to study the effect of Ce4+ and Zn2+ on microstructure. Magnetic behavior of co-doped barium hexaferrites in the low temperature regime, 2–300 K has been studied. Further, it has been explained on the basis of superexchange interactions and formation of Bloch walls due to the presence of imperfections in the doped samples. It has been found that BFO changes hard to soft magnetic behavior when the temperature is decreased from 300 K to 2 K. Moreover, doping of Ce4+ and Zn2+ at Fe3+ site also brings similar effects which strengthens with decreasing temperature.

Preparation of Ce–Zn substituted barium hexaferrites and investigation of their magnetic behavior in low temperature regime (2–300 K).  相似文献   
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We describe a case of oesophago-pleuro-cutaneous fistula occurring as a complication of tuberculous pyopneumothorax in a young adult.  相似文献   
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Prior work proposed a shortened version of the Social Responsiveness Scale (SRS), a commonly used quantitative measure of social communication traits. We used data from 3031 participants (including 190 ASD cases) from the Environmental Influences on Child Health Outcomes (ECHO) Program to compare distributional properties and criterion validity of 16-item “short” to 65-item “full” SRS scores. Results demonstrated highly overlapping distributions of short and full scores. Both scores separated case from non-case individuals by approximately two standard deviations. ASD prediction was nearly identical for short and full scores (area under the curve values of 0.87, 0.86 respectively). Findings support comparability of shortened and full scores, suggesting opportunities to increase efficiency. Future work should confirm additional psychometric properties of short scores.

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Journal of Artificial Organs - Veno-venous extracorporeal membrane oxygenation (ECMO) is typically instituted in severe respiratory failure, defined by Lung Injury Score, and caused either by...  相似文献   
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Aim

To study associations of dermatoglyphic features with malocclusion in Indian children.

Materials and methods

A total of 237 children aged 12–16 years, who attended our outpatient clinic in a government medical college, were selected. Finger and palm prints were collected, and fingertip pattern frequencies, total ridge counts (TRCs), and atd angles (formed by the triradii below the first and last digits and that in the hypothenar region of the palm) were calculated. These parameters were analyzed with their Angle’s class of malocclusion using appropriate statistical tests. Dermatoglyphic parameters were examined and asymmetry analysis was conducted in subjects with different occlusion patterns.

Results

Although no fingerprint pattern was found to be specific for a particular class of occlusion, increased tendencies toward high frequencies of whorls in subjects with class II malocclusion and plain arches in those with class III malocclusion were observed. Significant differences in atd angle and TRC were observed among malocclusion types (p = 0.0001). Asymmetry scores did not differ significantly.

Conclusion

Dermatoglyphic analysis can be used as an indicator of malocclusion at an early age, thereby aiding the development of treatments aiming to establish favorable occlusion. Inheritance and twin studies, as well as those conducted in different ethnic groups, are required to examine these relationships further.  相似文献   
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