Authentic representative gum exudate samples from Acacia species namely Acacia senegal var. senegal (ASG), Acacia mellifera (AMF), Acacia seyal var. seyal (ASY), and Acacia tortilis var. raddiana ...(ATR), were physicochemically analyzed. The moisture, ash, nitrogen and protein content, pH, specific optical rotation, and number average molecular weight were found to be ranging from 9.76% to 8.35%, 3.40% to 2.05%, 0.243% to 1.549%, 1.610% to 10.378%, 4.45 to 4.94, −48.25 to +86.75 and 0.24×106 to 2.95×106 respectively. The 13C and 1H NMR spectra of gum samples showed similarity in individual sugar components, but characteristic patterns of each gum, were observed. FTIR spectra of the studied gums show the presence of the same functional groups in the four gums. DSC and TGA thermograms were characteristic for each gum. Evaluation of the functional properties of the four gums indicated that ATR gum bears the best emulsification characteristics in terms of emulsion’s stability and emulsification power.
Effective energy storage has now become increasingly critical as global energy demand has skyrocketed. Asymmetric supercapacitors using electrodes made of acacia wood-derived carbon doped with MnO2. ...A hydrothermal process was used to synthesize the AWPC/MnO2 composite. Techniques such as XRD, SEM, TEM, XPS, FTIR spectra, Ramman spectra, and N2 adsorption-desorption isotherms. We looked at the electrochemical properties of the materials we made in an electrolyte using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). A hydrothermal synthesis approach is used to graft MnO2 wire-like nanostructures onto acacia wood-derived activated carbon. Good electrochemical performance is shown by the carbon/MnO2 hybrid composite electrode, which has high specific capacitances of 301 F g−1 at 500 mA s−1, low Tafel slope of 54 mV dec−1, which is attributed to the synergistic influences between MnO2 and waste biomass-produced carbon. Moreover, an asymmetric supercapacitor operating in the voltage range of 1.8 V and exhibiting a high energy density of 25 Wh kg−1 at a power density of 450 W kg−1 demonstrates the significant potential of the activated carbon/MnO2 composite generated from synthesized biomass. The AWPC/MnO2's oxygen evolution reaction (OER) activity was checked to see how well the improved nanostructure could be used. The results offer a fresh perspective on the fabrication of electrochemical energy storage devices with outstanding performance.
This study aimed to characterize the exudate gum from Acacia nilotica var. nilotica in Sudan and compare its physicochemical properties to Acacia seyal var. seyal and Acacia senegal var. senegal (gum ...Arabic). Samples were collected from six different states in Sudan over three seasons. The gum had a moisture content of 10.50%, ash content of 1.86%, pH value of 5.19, specific optical rotation of +94.70, intrinsic viscosity of 10.44 cm3 g-1, nitrogen content of 0.024%, protein content of 0.16%, acid equivalent weight of 1907.82, and total uronic acid content of 10.18%. Sugar content analysis revealed arabinose (41.20%), galactose (17.43%), and rhamnose (10.68%). Potassium was the predominant cation, followed by calcium, magnesium, sodium, lead, and iron. Acacia nilotica was classified as part of the Gummeferae series and exhibited a positive specific optical rotation. The Number average molecular weight (Mn) was estimated using osmometric measurements and gel permeation chromatography. The gum had a higher molecular weight and lower intrinsic viscosity compared to gum Arabic, suggesting a spheroidal shape of molecule. Amino acid analysis showed similarities with gum Arabic, with hydroxyproline and serine as principal amino acids. Variations in cationic composition were attributed to differences in soil type among collection locations. KEY WORDS: Physicochemical characterization, Acacia senegal var. senegal gum, Acacia seyal var. seyal gum, Acacia nilotica var. nilotica gum, gammiferae Bull. Chem. Soc. Ethiop. 2024, 38(4), 839-852. DOI: https://dx.doi.org/10.4314/bcse.v38i4.2
Burnout prevalence and its consequences on healthcare workers during the Omicron wave are not well investigated in Sudan. This study aims to assess the prevalence of burnout and its associated ...factors among doctors and nurses during the omicron wave in COVID-19 isolation centres in Khartoum, Sudan.
This cross-sectional survey study was conducted at multiple COVID-19 isolation centres in Khartoum state during the omicron wave of Coronavirus Disease 2019 between 20th February 2022 and 10th April 2022. A total of 306 doctors and nurses filled out the questionnaire, with a response rate of 64.8℅. They were recruited from 5 isolation centers scattered in the three cities of Khartoum Metropolis. The level of burnout was assessed using an online semi-structured questionnaire based on the Oldenburg Burnout Inventory questionnaire. Descriptive statistics were used for continuous variables and frequencies with percentages for categorical variables. The Chi-square test and Fisher exact test were used to identify variables associated with burnout. Logistic regression was used to determine the factors associated with burnout, and the p-value of ≤ .05 is considered statistically significant.
The prevalence of burnout was 45.7%. Doctors were more likely to have burnout than nurses (OR: 2.01, CI 95% 1.24-3.27; p = 0.005). Also, married healthcare workers were more likely to suffer burnout than single healthcare workers (OR: 3.89, CI 95% 1.41-12.5; P = 0.013). The number of household members (p = 0.035) was associated with burnout among participants.
There is a high prevalence of burnout among healthcare workers in Khartoum Isolation Centers, which is more apparent among doctors.
Density functional theory (DFT) computations were done to explore the optical and electronic properties of two conjugated molecules, emodin and purpurin, as potential organic semi-conductors. The ...molecules were functionalized to explore the impact of functionalization on the electronic and optical properties. The properties calculated include reorganization energy (λh and λe), adiabatic ionization potential (IP), adiabatic electron affinity (EA), chemical hardness (n), HOMO and LUMO energies, and HOMO-LUMO energy gap (Eg) via B3LYP/6–3++G (d, p) method. In addition, the maximum absorption (λmax) and oscillator strength (f) at the excited states in vacuum and solvent (Ethanol) were investigated using time-dependent density functional theory (TD-DFT). The introduction of functional groups to emodin was considered to convert the molecule from a p-type into an n-type material, while purpurin is considered as an n-type material, its functionalization with NO2 and 2F resulted in a slight increase in λe values, which is considered detrimental for the process of charge-transport. However, the functionalized molecules have shown an increase in EA and a decrease in LUMO energy level, indicating their potential use as n-type materials. Furthermore, to have an understanding of the intermolecular interactions in emodin and purpurin molecules, Hirshfeld surface analysis and energy framework were studied.
Malaria and coronavirus disease 2019 (COVID‐19) share several characteristics that could lead to cross‐infection, particularly in malaria‐endemic areas. Early COVID‐19 symptoms might be misdiagnosed ...for malaria in clinical settings. Also, both diseases can cause fatal complications. So, laboratory testing for both diseases was recommended by the World Health Organization. To study the clinical characteristics and outcomes of Adult Sudanese patients with COVID‐19 and malaria coinfection. This retrospective cross‐sectional study was conducted from January 2021 to October 2021 in Wad Medani. Total coverage of all Sudanese patients above 18 years old with a confirmed diagnosis of coinfection with COVID‐19 and malaria was included, and data were collected using a data collection sheet. Data were analyzed using R software version 4.0.2. Data were described and presented as mean, standard deviation, and number (percentage). To find associated factors with in‐hospital outcome, χ2 test, fisher exact test, and independent t test or Wilcoxon rank‐sum test were used. In this study, 156 participants were diagnosed with COVID‐19 and malaria coinfection. Most of them were between 60 and 70 years (30.8%), the majority were males (59%). Shortness of breath (76.3%) and acute respiratory distress syndrome (35.3%) were the most common symptom and complications among coinfected patients, respectively. Ground glass opacity (n = 47/49, 95.9%) is the most common result for computed tomography scan. Atrial fibrillation was the most common abnormal electrocardiogram finding (n = 6/62, 9.7%). Overall mortality among all participants was (63/156, 40.4%). High mortality rate was found among the coinfected patients. More attention is needed towards fighting COVID‐19 and malaria coinfection. There may be a link between malaria and COVID‐19.
Since December 2019, an outbreak of severe respiratory infection (COVID-19) emerged in the city of Wuhan in China. The knowledge, awareness and practice of medical students toward COVID-19 pandemic ...is of most importance as it demonstrates their preparedness to deal with this pandemic. The objective of this study is to assess the knowledge, awareness and practice of medical students in Sudan universities about COVID 19.
This is a cross-sectional study conducted on 19 universities that have medical schools in Sudan. Data from at least 100 medical students from each university were included in the study. Data were collected using an online questionnaire in April 2020. Statistical analysis was conducted using the Statistical Package for Social Science software, version 25.
About 2603 medical students from 19 universities were included. Overall good knowledge and practice were demonstrated by the medical students (88.9%) and (78.6%), respectively. Respondents who answered that the most common clinical symptoms of COVID-19 were the main combination of dry cough, fatigue and fever were (27.7%), and the first initial symptom was headache were (48.3%.). (60.2%) Wear medical masks, (95%) said that avoiding crowded places protects against the spread of COVID-19, and (50.7%) have confidence that Sudan can win the battle against the COVID-19. Finally, (68.8%) agreed that COVID-19 will finally be successfully controlled.
This study has found that medical students in Sudan demonstrated good knowledge and good practice toward Covid19.
•Covid-19 pandemic has captured the attention of the world due to severe political, social, psychological, and economic influences.•This study has found that medical students in Sudan demonstrated good knowledge and good practice toward COVID-19.
The synthesis, characterization, and hydrogel properties of starch-g-(
tert
-butylacrylate) and starch-g-(
n
-butylacrylate) copolymers were studied. The optimum conditions for the grafting process ...of
tert
-butylacrylate into 1.0 g of starch were as follows:
tert
-butylacrylate = 0.04 mol/L, CAN = 9.0 × 10
−4
mol/L, temperature = 20 °C in 100 mL solution, whereas the results using
n
-butylacrylate monomer were as follows:
n
-butylacrylate = 0.04 mol/L, CAN = 4.0 × 10
−3
mol/L, temperature = 30 °C in 100 mL solution. The grafting evidences of monomers into starch were done through TG and its derivative DTG for thermal changes and mass losses, scanning electron microscope (SEM) for morphological changes, powder X-ray for crystallinity measurements and FTIR for functional group changes. Acid hydrolysis method was used efficiently to allow the calculations of the viscosity average molecular weight (
M
v
) of the grafted chains on starch and consequently the real percent of grafting efficiency (i.e. %GY). The capability of starch-g-(
n
-BAC) hydrogel to absorb water were found 10 times more than starch-g-(
tert
-BAC) hydrogel, which were clarified through the X-ray and SEM results.
The optical and electronic properties of two conjugated organic molecules, Indigo and Alizarin, as potential organic solar cells were studied theoretically. The electronic properties, reorganization ...energy (λh and λe), adiabatic Ionization potential (IA), adiabatic Electron affinity (EA),HOMO, LUMO and Energy gap (Eg) were calculated using DFT. The optical properties as the maximum absorption (λmax) along with oscillator strengths (f) at the excited states in vacuum and solvent were also calculated using TD-DFT. The molecules were functionalized by electronegative functional groups to understand the effect of functionalization on the optical and electronic properties. It was found that the functionalization of Indigo and Alizarin has resulted in overall conversion of the materials to better n-type molecules. The Eg for both molecules has been generally reduced upon the introduction of electronegative functional groups. This indicates the possibility of tuning organic molecules optical and electronic properties by introducing functional groups. Also, both studied molecules along with their functionalized molecules show properties that fall among organic semiconductors and thereby, can be potentially used in solar cells.
Display omitted
•The functionalization resulted in tuning their optical and electronic properties.•Functionalized Indigo and Alizarin shows semi-conductor materials properties and can be potentially used as organic semi-conductors for solar cells applications.•The functionalization of the Indigo and Alizarin, resulted in tuning their optical and electronic properties.•The functionalization of Indigo and Alizarin by electronegative functional groups results in their overall conversion into n-type materials.
PDF
