Preparation of chitin nanofibers by surface esterification of chitin with maleic anhydride and mechanical treatment

Esterification with maleic anhydride significantly improved the mechanical disintegration of chitin into uniform 10-nm nanofibers. Nanofibers with 0.25° of esterification were homogeneously dispersed in basic water due to the carboxylate salt on the surface. Esterification proceeded on the surface and did not affect the relative crystallinity. A cast film of the esterified chitin nanofibers was highly transparent, since the film was free from light scattering

Protein/CaCO3/Chitin Nanofiber Complex Prepared from Crab Shells by Simple Mechanical Treatment and Its Effect on Plant Growth

A protein/CaCO3/chitin nanofiber complex was prepared from crab shells by a simple mechanical treatment with a high-pressure water-jet (HPWJ) system. The preparation process did not involve chemical treatments, such as removal of protein and calcium carbonate with sodium hydroxide and hydrochloric acid, respectively. Thus, it was economically and environmentally friendly. The nanofibers obtained had uniform width and dispersed homogeneously in water. Nanofibers were characterized in morphology, transparency, and viscosity. Results indicated that the shell was mostly disintegrated into nanofibers at above five cycles of the HPWJ system. The chemical structure of the nanofiber was maintained even after extensive mechanical treatments. Subsequently, the nanofiber complex was found to improve the growth of tomatoes in a hydroponics system, suggesting the mechanical treatments efficiently released minerals into the system. The homogeneous dispersion of the nanofiber complex enabled easier application as a fertilizer compared to the crab shell flakes

Correction: Incidence and predictors of treatment failure among children on first-line antiretroviral therapy in Amhara Region Referral Hospitals, northwest Ethiopia 2018: A retrospective study.

[This corrects the article DOI: 10.1371/journal.pone.0215300.]

Protein/CaCO3/Chitin Nanofiber Complex Prepared from Crab Shells by Simple Mechanical Treatment and Its Effect on Plant Growth

A protein/CaCO3/chitin nanofiber complex was prepared from crab shells by a simple mechanical treatment with a high-pressure water-jet (HPWJ) system. The preparation process did not involve chemical treatments, such as removal of protein and calcium carbonate with sodium hydroxide and hydrochloric acid, respectively. Thus, it was economically and environmentally friendly. The nanofibers obtained had uniform width and dispersed homogeneously in water. Nanofibers were characterized in morphology, transparency, and viscosity. Results indicated that the shell was mostly disintegrated into nanofibers at above five cycles of the HPWJ system. The chemical structure of the nanofiber was maintained even after extensive mechanical treatments. Subsequently, the nanofiber complex was found to improve the growth of tomatoes in a hydroponics system, suggesting the mechanical treatments efficiently released minerals into the system. The homogeneous dispersion of the nanofiber complex enabled easier application as a fertilizer compared to the crab shell flakes

Delayed neuropsychiatric sequelae due to long-term effects of carbon monoxide poisoning in Ethiopia: A case report

Background: One emergency that occurs frequently and has high morbidity is carbon monoxide poisoning. After a time of lucidity, some victims who recover from the incident of acute carbon monoxide exposure may later suffer delayed neuropsychiatric sequelae (DNS), which can include cognitive impairments, a wide range of neurological abnormalities, and affective disorders. Below, we report the first documented incident of DNS after carbon monoxide poisoning in Ethiopia. Case presentation: A 40-year-old male patient who developed a coma after he was exposed to burning charcoal in a closed room was admitted to Debre Tabor Comprehensive Specialized Hospital in the northwest region of Ethiopia. He stayed for 12 days during his first admission and was discharged with improvement. One month after discharge, he developed delayed neuropsychiatric sequelae, which manifested as bizarre behavior, being unable to walk unsupported, loss of concentration, and failure to control urine and feces. Brain MRI showed bilateral periventricular and frontoparietal deep white matter subcortical abnormal T1 and T2 prolongation with no restriction of diffusivity, possibly due to demyelinating disorders. He was managed with fluid therapy, benzhexol, risperidone, and rehabilitation therapy. He stayed for two weeks in our hospital and was discharged with improvement. Conclusion: Despite the paucity of delayed neuropsychiatric sequelae from carbon monoxide poisoning, physicians should be highly suspicious in the right situations. The precise mechanisms of delayed toxic effects, prevention measures, and treatment modalities have not yet been determined; therefore, more research and attention are required