Psychological impact, coping behaviors, and traumatic stress among healthcare workers during COVID-19 in Taiwan: An early stage experience.

OBJECTIVE: This study investigated the psychological impact on, coping behaviors of, and traumatic stress experienced by healthcare workers during the early stage of the COVID-19 pandemic and formulated effective support strategies that can be implemented by hospitals and government policymakers to help healthcare staff overcome the pandemic. METHODS: This cross-sectional study recruited clinical healthcare workers at a regional hospital in Nantou County, Taiwan. The questionnaire collected personal characteristics, data on the impact and coping behaviors of the pandemic, and Impact of Event Scale-Revised (IES-R). A total of 354 valid questionnaires were collected. The statistical methods employed were univariate and multivariate stepwise regression, and logistic regression. RESULTS: Perceived impact and coping behaviors were found to be moderate in degree, and traumatic stress was lower than that in other countries. However, our data identified the following subgroups that require special attention: those with young age, those living with minor children, nurses, those with self-rated poor mental health, and those with insufficient COVID-19-related training. CONCLUSION: Managers should pay particular attention to helping healthcare workers in high-risk groups, strengthen COVID-19 training, provide adequate protective equipment and shelter, and offer psychological counseling.

Very large photoresponsiviy and high photocurrent linearity for Ge-dot/SiO2/SiGe photoMOSFETs under gate modulation.

We report a novel visible-near infrared photoMOSFET containing a self-organized, gate-stacking heterostructure of SiO2/Ge-dot/SiO2/SiGe-channel on Si substrate that is simultaneously fabricated in a single oxidation step. Our typical photoMOSFETs exhibit very large photoresponsivity of 1000-3000A/W at low optical power (< 0.1µW) or large photocurrent gain of 103-108A/A with a wide dynamic power range of at least 6 orders of magnitude (nW-mW) linearity at 400-1250 nm illumination, depending on whether the photoMOSFET operates at VG = + 3- + 4.5V or -1- + 1V. Numerical simulations reveal that photocarrier confinement within the Ge dots and the SiGe channel modifies the oxide field and the surface potential of SiGe, significantly increasing photocurrent and improving linearity.

High Photoresponsivity Ge-dot PhotoMOSFETs for Low-power Monolithically-Integrated Si Optical Interconnects.

We report the demonstration of high-photoresponsivity Ge-dot photoMOSFETs in a standard MOS configuration for the detection of 850-1550 nm illumination. Each device has a self-organized, gate-stacking heterostructure of SiO2/Ge-dot/SiO2/SiGe-channel which is simultaneously fabricated in a single oxidation step. Superior control of the geometrical size and chemical composition for our Ge nanodots/SiO2/Si1-xGex-shell MOS structure enables the practically-achievable, gate-stacking design for our Ge-dot photoMOSFETs. Both the gate oxide thickness and the diameter of the Ge dots are controllable. Large photocurrent enhancement was achieved for our Ge-dot photoMOSFETs when electrically-biased at ON- and OFF-states based on the Ge dot mediating photovoltaic and photoconductive effects, respectively. Both photoelectric conversion efficiency and response speed are significantly improved by reducing the gate-oxide thickness from 38.5 nm to 3.5 nm, and by decreasing Ge-dot size from 90 nm to 50 nm for a given areal density of Ge dots. Photoresponsivity () values as high as 1.2 × 104 A/W and 300 A/W are measured for 10 nW illumination at 850 nm and 1550 nm, respectively. A response time of 0.48 ns and a 3 dB-frequency of 2 GHz were achieved for 50 nm-Ge-dot photoMOSFETs with channel lengths of 3 µm under pulsed 850 nm illumination.