The 2019 novel-coronavirus has affected 181 countries with approximately 1197405 confirmed cases (by 5th April). Understanding the transmission dynamics of the infection in each country which got affected on a daily basis and evaluating the effectiveness of control policies are critical for our further actions. To date, the statistics of COVID-19 reported cases show that more than 80% of infected are mild cases of disease, around 14% of infected have severe complications, and about 5% are categorized as critical disease victims. Today's report (5th April 2020; daily updates in the prepared website) shows that the confirmed cases of COVID-19 in the United States, Spain, Italy, and Germany are 308850, 126168, 124632, and 96092, respectively. Calculating the total case fatality rate (CFR) of Italy (4th April 2020), about 13.3% of confirmed cases have passed away. Compared with South Korea's rate of 1.8% (seven times lower than Italy) and China's 4% (69% lower than Italy), the CFR of Italy is too high. Some effective policies that yielded significant changes in the trend of cases were the lockdown policy in China, Italy, and Spain (the effect observed after some days), the shutdown of all nonessential companies in Hubei (the effect observed after 5 days), combined policy in South Korea, and reducing working hours in Iran.
Simultaneous Saccharification, Filtration and Fermentation (SSFF) was developed for lignocellulosic ethanol production. In SSFF, pretreated lignocellulosic material is enzymatically hydrolyzed in a reactor, while the suspension is continuously pumped through a cross-flow membrane. The retentate goes back to the hydrolysis vessel, while a clear sugar-rich filtrate continuously perfuses through the fermentation vessel before it is pumped back to the hydrolysis vessel. The capacity and life span of the cross-flow filter module was examined for four weeks using enzymatically hydrolyzed slurry, initially with 14.4% suspended solids, without clogging or fouling. An ethanol yield of 85.0% of the theoretical yield was obtained in SSFF and a flocculating strain of Saccharomyces cerevisiae was successfully reused for 5 cultivations of SSFF.
Shortcomings of the conventional PLA synthesis methods have encouraged researchers to investigate on alternative methods for PLA synthesis. Utilization of chain extenders is an effective way to achieve high MW polymers. The concept of using star-shaped resins as the reinforced matrices for biocomposites or in biomedical applications is gaining more and more attention day by day. Star-shaped lactic acid based resins are a class of branched resins with a multifunctional core molecule and lactic acid branches. In order to increase the reactivity of branches, the star-shaped resin oligomers can get end-functionalized which yields in a crosslinkable product. Changing the architecture of a polymer from a linear to a multiarm or hyperbranched one, would change its chemical, diffusional and physical-mechanical properties. This review paper presents the current state and recent advances in the synthesis, characterization, properties and applications of the star-shaped resins made from lactic acid and multi-hydroxyl core molecules with a focus on the role of the morphology of the polymer on the 3 properties of resins. Rheological, physiochemical and thermomechanical properties of to date synthesized star-shaped resins are compared and discussed. Special emphasis would be made on potential opportunities, probable applications and also gaps and drawbacks concerning these systems. This review aims to provide useful information to help future development of efficient, highly engineered bioresins which can be especially designed for a certain application.
The 2019-Novel-Coronavirus (COVID-19) has affected 181 countries and out of about 1197405 confirmed cases (By April 5). Understanding the transmission dynamics of the infection in each country which affected on a daily basis and evaluating the effectiveness of control policies is critical for our further actions. To date, the statistics of COVID-19 reported cases show more than 80 percent of infected had a mild case of disease, while around 14 percent of infected experienced a severe one and about 5 percent are categorized as critical disease victims. Today's report (2020-04-05; daily updates in the prepared website) shows the confirmed cases of COVID-19 in the US, Spain, Italy, and Germany are 308850, 126168, 124632, and 96092; respectively. Calculating the total Case Fatality Rate (CFR) of Italy (2020-04-04), about 13.3% of confirmed cases passed away. Compared to South Korea's rate of 1.8% (7 times lower than Italy) and China's 4% (69% lower than Italy), the CFR of Italy is too high. There are some effective policies that yield significant changes in the trend of cases. The lockdown policy in China, Italy, and Spain (the effect observed after some days), Shutdown of all non-essential companies in Hubei (the effect observed after 5 days), combined policy in South Korea, and reducing working hours in Iran.
A biobased thermoset resin was synthesized by direct condensation reaction of lactic acid with xylitol followed by the end-functionalization of the hydroxyl groups of branches by methacrylic anhydride. Chemical structures of resins were evaluated and confirmed by 13 C NMR and Fourier-transform infrared spectroscopy (FT-IR). Different techniques were employed for the optimization of the curing process. Techniques including Microscopy, Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Thermal Analysis (DMTA) were employed for characterization of the cured resins. Thermogravimetric analyses (TGA) were also carried out to check the thermal stability of the cured resins. The viscosity of the neat resin was measured at different temperatures and different stress levels. Water adsorption tests were also carried out to check the water absorption properties of cured resins. The glass temperature (Tg) of the resin was 98°C, and the viscosity of the resin was 2.97 Pa s at room temperature which drops to 0.07 Pa s upon increasing the temperature to 85°C. The biobased content of the resin was calculated
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