Estimation of the Seasonal Inhaled Deposited Dose of Particulate Matter in the Respiratory System of Urban Individuals Living in an Eastern Mediterranean City.

In this study, we present an estimation for the inhaled deposited dose rate in adult males and females during common exposure scenarios to urban background aerosols in an Eastern Mediterranean city (Amman, Jordan) based on a one-year database of measured particle number size distribution. The dose rates show seasonal variations reflecting the physical characteristics (i.e., modal structure) of the particle number size distribution. An additional factor was the varying deposition fraction (DF) for different regions and different human activities (exercising versus resting). The total dose rate was 3 × 109-65 × 109 particles/h (PM2.5 and PM10 doses 1-22 µg/h and 9-210 µg/h; respectively) depending on the gender, activity, and season. Based on the particle number metrics, the inhaled deposited dose in the head, Tracheobronchial, and alveolar were 7-16%, 16-28%, and 56-76%; respectively. Based on the PM2.5 metric, the corresponding dose rate was 9-41%,13-19%; and 46-72% respectively. As for the PM10 metric, they were 25-75%, 7-35%, and 15-55%; respectively.

COVID-19 Pandemic Development in Jordan-Short-Term and Long-Term Forecasting.

In this study, we proposed three simple approaches to forecast COVID-19 reported cases in a Middle Eastern society (Jordan). The first approach was a short-term forecast (STF) model based on a linear forecast model using the previous days as a learning data-base for forecasting. The second approach was a long-term forecast (LTF) model based on a mathematical formula that best described the current pandemic situation in Jordan. Both approaches can be seen as complementary: the STF can cope with sudden daily changes in the pandemic whereas the LTF can be utilized to predict the upcoming waves' occurrence and strength. As such, the third approach was a hybrid forecast (HF) model merging both the STF and the LTF models. The HF was shown to be an efficient forecast model with excellent accuracy. It is evident that the decision to enforce the curfew at an early stage followed by the planned lockdown has been effective in eliminating a serious wave in April 2020. Vaccination has been effective in combating COVID-19 by reducing infection rates. Based on the forecasting results, there is some possibility that Jordan may face a third wave of the pandemic during the Summer of 2021.