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This paper reports the findings of spin density functional theory (DFT) calculations on the electronic properties of nitrogen (N)-doped (TiO2)33 nanocrystals as a function of different low-index facets [(001), (011), (101)] at the surface and subsurface. The formation energy (Ef) of the impurity at different facets of nanocrystals and in different nitrogen concentrations for substitutional sites has been calculated. The formation energy of the N-doped (TiO2)33 nanocrystal at (101) facet was low at both low (Ti33O65N1) and high (Ti33O64N2) concentrations. Similarly, at low and high concentrations, the lengths of the bonds surrounding the impurity (N) dopant varied with the different facets. Regarding the electronic properties, different locations of nitrogen impurity in various facets have distinctly different electronic structures. These structures contributed to deep and shallow states in the gap level of nanocrystals (TiO2)33. In addition, valence band tailing has been observed, resulting in a band gap narrowing. This study observed that N-doped (TiO2)33 nanocrystals exhibit various structural and electronic properties depending on the dopant facets. Because of these properties, the material is selectively suitable for a wide range of purposes and applications. [ABSTRACT FROM AUTHOR]

Background: Both creatine kinase (CK) and/or lactate dehydrogenase (LDH) mutually are elevated significantly in many tumors. This study hypothesizes that LDH was evaluated as a prognostic factor for survival time in patients with terminal cancer (PTC). Additionally, CK considered as a valuable in assessing prognosis of advanced cancer patients. This study aimed to estimate the change in the CK/LDH levels in patients with different types of cancer comparing with the controls, and to investigate their prognostic significance for survival time termination in PTC. Methodology: The study was performed at Cancer Central Research Clinic in Baghdad. We quantitated CK/ LDH using the colorimetric method in sixty PTC, and twenty age/sex-matched healthy adults. Results: Serum values of CK/LDH were significantly increased in PTC compared to the controls (p<0.001). There was a weak non-significant correlation between CKLDH in PTC and control. There was a non- significant correlation of CK to LDH levels in different cancer types, except in patients with lymphatic cancer. Conclusion: In agreement with our hypothesis, serum levels of CK/LDH were significantly increased as the patients approached death. [ABSTRACT FROM AUTHOR]

The purpose of this study is to obtain data from vocational school teachers about their perceptions of elearning learning activities in facing the COVID-19 pandemic. Respondents are vocational teachers who conduct learning activities using e-learning. This survey uses a questionnaire that consists of teacher knowledge of elearning, the preparation, the application, and evaluation of learning using e-learning. This research is descriptive with a survey method. Researchers distributed questionnaires to vocational high school teachers in West Java using Google Form from September to October 2020. There are 15 vocational schools with a total of 82 teachers. After that, the researchers analyzed the collected data. The results show that vocational school teachers perceive e-learning learning as a learning medium using the internet network. Furthermore, for the perception of vocational school teachers in preparing for e-learning learning, 60% state that they do not encounter problems, 71% of teachers mention it is easy to implement. However, as for the perception of vocational teachers in the e-learning evaluation is 73% state that e-learning still consists of learning content that is difficult for students to understand. The findings show the necessity of vocational teachers to have sufficient preparation when implementing e-learning to achieve the learning objectives. [ABSTRACT FROM AUTHOR]

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