Chest radiographs in Coronavirus Disease 2019 (COVID-19).

OBJECTIVES: To recognize the radiographic patterns of coronavirus disease 2019 (COVID-19) in Malaysia. MATERIALS AND METHODS: Chest radiographs of patients confirmed with COVID-19 in Hospital Tawau, Sabah, Malaysia were retrospectively analyzed by two radiologists. The radiographic pattern, distribution among subgroups and evolution of the disease over time were determined. RESULTS: Among the 82 patients studied, 65 (79.3%) were males. Mean age of our cohorts was 37 ± 15 years. Baseline chest radiographs were abnormal in 37 patients (45.1%). Over half (52.9%) of the symptomatic patients had abnormal baseline radiograph. Among the children, patients with comorbidities, and patients 60 years of age and above, the abnormal radiographs were 14.3%, 71.4% and 69.3% respectively. Ground glass opacities were the commonest abnormal radiographic feature (35.4%), were peripherally located (35.4%) with predilection for the lower zones (29.3%). Most radiographic abnormalities were multifocal (20.7%) and frequently located in the left lung (19.5%). Radiographic recovery was observed in 15 of 18 patients (83%). Computed tomography (CT) scan demonstrated greater extent of the disease than observed in radiographs of the same patient. CONCLUSIONS: COVID-19 pneumonia presented with a specific radiographic pattern in our cohort of patients, comprising of ground glass opacities in peripheral and basilar distribution, affecting a single lung field and was observed in both symptomatic and asymptomatic patients. Chest radiograph is a useful adjunct screening tool, and in combination with clinical and epidemiological assessment may facilitate in early diagnosis of COVID-19 pneumonia.

Factors predicting screen time related to physical and behavioural complaints in primary school children.

BACKGROUND AND OBJECTIVE: Physical and behavioural problems from extended usage of electronic devices are issues among primary school children. This study is aimed to investigate the prevalence of physical and behavioural complaints arising from the electronic device usage and to identify the potential factors that predicted the complaints. METHODS: This was a primary school-based cross-sectional study using multistage cluster sampling, conducted at Bau district in Sarawak, Malaysia in 40 primary schools. A questionnaire was used to collect information of usage pattern in insufficient lighting, timing and position. The physical and behavioural complaints were traced. Data analysis was performed using SPSS version 22. A p-value < 0.05 with 95% CI was considered as statistically significant. RESULTS: About 52.8% of the 569 students used digital devices in a bright room, 69.8% in the day time and 54.4% in sitting position. The physical complaints were headache (32.9%), neck, shoulder and back pain (32.9%) followed by by eye strain (31.8%). Regarding behavioural problems, 25.7% of the students had loss of interest in study and outdoor activities (20.7%), skipped meals (19.0%) and arguments/disagreements with parents (17.9%). After logistic regression analysis, the lying position (OR=1.71, 95% CI: 1.096, 2.688) and darkroom lighting (OR=2.323 95% CI: 1.138, 4.744) appeared to be potential predictors of the complaint. CONCLUSION: One-quarter of the students studied experienced physical complaints, and one-fifth had behavioural problems associated with the use of electronic devices. Lying position and darkroom lighting are the potential predictors of complaints. Therefore, we suggest that the children should use electronic devices in the sitting position with adequate room lighting.

High performance all-fiber temperature sensor based on coreless side-polished fiber wrapped with polydimethylsiloxane.

A novel fiber structure, coreless side-polished fiber (CSPF) that is wrapped by polydimethylsiloxane (PDMS), is demonstrated to be highly sensitive to temperature because of the high refractive index sensitivity of the CSPF and the large thermal optic coefficient of the PDMS. Our numerical and experimental results show that the several dips in the transmitted spectra of PDMSW-CSPF is originated from the multimode interference (MMI) in the CSPF and will blueshift with the increase of temperature. Furthermore, for such a PDMSW-CSPF, we investigate its temperature sensing characteristics and the influences of residual thickness (RT) and dip wavelength on the sensitivity both numerically and experimentally. In the temperature range of 30~85°C, the PDMSW-CSPF with RT = 43.26 µm exhibits a high temperature sensitivity of -0.4409 nm/°C, the high linearity of 0.9974, and the high stability with low standard deviation of 0.141 nm. Moreover, in the cycle experiments, where the environmental temperature was set to automatically increase and then decrease, the PDMSW-CSPF exhibits a low relative deviation of sensitivity (RSD) of down to ± 0.068%. Here, the RSD is defined as the ratio of sensitivity deviation to the average sensitivity measured in the heating/cooling cycle experiments. The lower RSD indicates that PDMSW-CSPF has better reversibility than other fiber structure. The investigations also show that the sensitivity of the PDMSW-CSPF could be enhanced further by reducing the residual thickness and choosing the dip at a longer wavelength.