Electrochemically Induced Mesomorphism Switching in a Chlorpromazine Hydrochloride Lyotropic Liquid Crystal

The discovery of electrochemical switching of the Lα phase of chlorpromazine hydrochloride in water is reported. The phase is characterized using polarizing microscopy, X-ray scattering, rheological measurements, and microelectrode voltammetry. Fast, heterogeneous oxidation of the lyotropic liquid crystal is shown to cause a phase change resulting from the disordering of the structural order in a stepwise process. The underlying molecular dynamics is considered to be a cooperative effect of both increasing electrostatic interactions and an unfolding of the monomers from "butterfly"-shaped in the reduced form to planar in the oxidized form

The Application of Hydroxyapatite NPs for Adsorption Antibiotic from Aqueous Solutions: Kinetic, Thermodynamic, and Isotherm Studies

Antibiotic pollution has become a serious concern due to the extensive use of antibiotics, their resistance to removal, and their detrimental effects on aquatic habitats and humans. Hence, developing an efficient antibiotic removal process for aqueous solutions has become vital. Amoxicillin (Amox) is one of the antibiotics that has been efficiently removed from an aqueous solution using hydroxyapatite nanoparticles (HAP NPs). The current study synthesizes and utilizes hydroxyapatite nanoparticles as a cost-effective adsorbent. Adsorbent dose, pH solution, initial Amox concentration, equilibrium time, and temperature are among the factors that have an evident impact on Amox antibiotic adsorption. The (200) mg dose, pH (5), temperature (25) °C, and time (120) min are shown to be the best-optimized values. The nonlinear Langmuir’s isotherm and pseudo-second-order kinetic models with equilibrium capacities of 4.01 mg/g are highly compatible with the experimental adsorption data. The experimental parameters of the thermodynamic analysis show that the Amox antibiotic adsorption onto HAP NPs powder is spontaneous and exothermic

Low-Cost and Eco-Friendly Hydroxyapatite Nanoparticles Derived from Eggshell Waste for Cephalexin Removal

This work describes the hydroxyapatite nanoparticle (HAP) preparation from eggshell waste and their application as an adsorbent for Cephalexin (Ceph) antibiotic removal from aqueous solutions. Chemical precipitation with phosphoric acid was used to evaluate the feasibility of calcium oxide for HAP preparation. The structural properties of HAP were characterized by X-ray diffraction, which revealed the formation of the hydroxyapatite crystalline phase formation. In addition, transmitting electron spectroscopy showed an irregular shape with a variation in size. The impact of various experimental conditions on the removal efficiency such as the solution’s pH, contact time, HAP mass, solution temperature, and Ceph concentration were studied. Experimental data showed that HAP could remove most Ceph species from aqueous solutions within 1 h at pH = 7 with 70.70% adsorption efficiency utilizing 50 mg of the HAP. The removal process of Ceph species by HAP was kinetically investigated using various kinetic models, and the results showed the suitability of the pseudo-second-order kinetic model for the adsorption process description. Moreover, the removal process was thermodynamically investigated; the results showed that the removal was spontaneous endothermic and related to the randomness increase. The data confirmed that HAP had high efficiency in removing Ceph antibiotics from an aqueous solution

Structural, Electronic, Reactivity, and Conformational Features of 2,5,5-Trimethyl-1,3,2-diheterophosphinane-2-sulfide, and Its Derivatives: DFT, MEP, and NBO Calculations

In this study, we used density functional theory (DFT) and natural bond orbital (NBO) analysis to determine the structural, electronic, reactivity, and conformational features of 2,5,5-trimethyl-1,3,2-di-heteroatom (X) phosphinane-2-sulfide derivatives (X = O (compound 1), S (compound 2), and Se (compound 3)). We discovered that the features improve dramatically at 6-31G** and B3LYP/6-311+G** levels. The level of theory for the molecular structure was optimized first, followed by the frontier molecular orbital theory development to assess molecular stability and reactivity. Molecular orbital calculations, such as the HOMO–LUMO energy gap and the mapping of molecular electrostatic potential surfaces (MEP), were performed similarly to DFT calculations. In addition, the electrostatic potential of the molecule was used to map the electron density on a surface. In addition to revealing molecules’ size and shape distribution, this study also shows the sites on the surface where molecules are most chemically reactive

Characteristics and outcomes of COVID-19 patients admitted to hospital with and without respiratory symptoms

Background: COVID-19 is primarily known as a respiratory illness; however, many patients present to hospital without respiratory symptoms. The association between non-respiratory presentations of COVID-19 and outcomes remains unclear. We investigated risk factors and clinical outcomes in patients with no respiratory symptoms (NRS) and respiratory symptoms (RS) at hospital admission. Methods: This study describes clinical features, physiological parameters, and outcomes of hospitalised COVID-19 patients, stratified by the presence or absence of respiratory symptoms at hospital admission. RS patients had one or more of: cough, shortness of breath, sore throat, runny nose or wheezing; while NRS patients did not. Results: Of 178,640 patients in the study, 86.4 % presented with RS, while 13.6 % had NRS. NRS patients were older (median age: NRS: 74 vs RS: 65) and less likely to be admitted to the ICU (NRS: 36.7 % vs RS: 37.5 %). NRS patients had a higher crude in-hospital case-fatality ratio (NRS 41.1 % vs. RS 32.0 %), but a lower risk of death after adjusting for confounders (HR 0.88 [0.83-0.93]). Conclusion: Approximately one in seven COVID-19 patients presented at hospital admission without respiratory symptoms. These patients were older, had lower ICU admission rates, and had a lower risk of in-hospital mortality after adjusting for confounders

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population