CoFe2O4/PANI/MWCNTs ternary hybrid composites. Synthesis, characterization, the effect of MWCNTs ratio and dye removal capability.

We have synthesized cobalt ferrite (CoFe2O4) using the sucrose auto-combustion method and subsequently employed the in situ polymerization technique to fabricate ternary composites comprising CoFe2O4, polyaniline (PANI), and multi-walled carbon nanotubes (MWCNTs). In this novel investigation, we explored the influence of varying MWCNTs ratios on these composites' structural, magnetic, thermal, and electrical properties. The crystal structures of the synthesized composites were analyzed using X-ray diffraction (XRD), while Fourier transform infrared (FT-IR) spectroscopy revealed changes in bonding patterns, including the disappearance of ferrite bonds and the emergence of new ones. Transmission electron microscopy (TEM) images illustrated a complete coating of PANI on both MWCNTs and CoFe2O4 particles, resulting in a substantial reduction in magnetization compared to pure CoFe2O4 ferrite due to PANI's nonmagnetic nature. Vibrating sample magnetometer (VSM) measurements confirmed this reduction, indicating a decrease to 7.3 emu.g-1. Thermal analysis demonstrated an enhancement in thermal stability with increasing MWCNTs content, as evidenced by an increase in the temperature equivalent for half decomposition (T50) from 486 to 522 °C for composites with 40% MWCNTs. Moreover, the electrical conductivity showed a corresponding rise with MWCNTs content, increasing from 3.1 × 10-3 Ω-1.cm-1 to 2.2 × 10-2 Ω-1.cm-1, possibly indicating charge transfer from PANI to MWCNTs. To assess practical applications, we investigated the ability of the composite with 40% MWCNTs to remove phenol red (PR) dye from aqueous solutions. Through a systematic study of adsorption parameters and kinetics, we determined optimal conditions for effective dye removal and elucidated the underlying adsorption mechanism. Our results demonstrated the composite's efficiency in dye removal, with a 6.4 mg·g-1 capacity for PR dye, highlighting its potential for environmental remediation efforts.

Nanocellulose-Based Passivated-Carbon Quantum Dots (P-CQDs) for Antimicrobial Applications: A Practical Review.

Passivated-carbon quantum dots (P-CQDs) have been attracting great interest as an antimicrobial therapy tool due to their bright fluorescence, lack of toxicity, eco-friendly nature, simple synthetic schemes, and possession of photocatalytic functions comparable to those present in traditional nanometric semiconductors. Besides synthetic precursors, CQDs can be synthesized from a plethora of natural resources including microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC). Converting MCC into NCC is performed chemically via the top-down route, while synthesizing CODs from NCC can be performed via the bottom-up route. Due to the good surface charge status with the NCC precursor, we focused in this review on synthesizing CQDs from nanocelluloses (MCC and NCC) since they could become a potential source for fabricating carbon quantum dots that are affected by pyrolysis temperature. There are several P-CQDs synthesized with a wide spectrum of featured properties, namely functionalized carbon quantum dots (F-CQDs) and passivated carbon quantum dots (P-CQDs). There are two different important P-CQDs, namely 2,2'-ethylenedioxy-bis-ethylamine (EDA-CQDs) and 3-ethoxypropylamine (EPA-CQDs), that have achieved desirable results in the antiviral therapy field. Since NoV is the most common dangerous cause of nonbacterial, acute gastroenteritis outbreaks worldwide, this review deals with NoV in detail. The surficial charge status (SCS) of the P-CQDs plays an important role in their interactions with NoVs. The EDA-CQDs were found to be more effective than EPA-CQDs in inhibiting the NoV binding. This difference may be attributed to their SCS as well as the virus surface. EDA-CQDs with surficial terminal amino (-NH2) groups are positively charged at physiological pH (-NH3+), whereas EPA-CQDs with surficial terminal methyl groups (-CH3) are not charged. Since the NoV particles are negatively charged, they are attracted to the positively charged EDA-CQDs, resulting in enhancing the P-CQDs concentration around the virus particles. The carbon nanotubes (CNTs) were found to be comparable to the P-CQDs in the non-specific binding with NoV capsid proteins, through complementary charges, π-π stacking, and/or hydrophobic interactions.

Structural and Magnetoelectrical Properties of MFe2O4 (M = Co, Ni, Cu, Mg, and Zn) Ferrospinels Synthesized via an Egg-White Biotemplate.

Nanocrystalline metal ferrites (MFe2O4, M = Co, Ni, Cu, Mg, and Zn) were successfully synthesized via autocombustion synthesis using egg white. X-ray diffraction (XRD) measurements revealed the crystallization of the entire ferrites either in the tetragonal structure, such as in the case of CuFe2O4, or cubic spinels such as in other studied ferrites. The Fourier transform infrared spectral study revealed the characteristic vibration bands of ferrites. Compared to other synthesis methods, the observed variation in the obtained structural parameters could be due to the different cation distribution of the prepared ferrites. In agreement with XRD measurements, the transmission electron microscopy images showed agglomerated particles with cubic morphology for all ferrites. On the other hand, CuFe2O4 showed tetragonal morphology. The magnetization values were found to vary with the type of the metal ion, and CoFe2O4 showed the highest one (42.8 emu/g). Generally, the lower magnetization values obtained than those reported in the literature for all studied ferrites could be attributed to the smaller particle sizes or the cation redistribution. The obtained coercivity values are observed to be higher than their related values in the literature, exhibiting the impact of the present synthesis route. Ac-conductivity as a function of temperature and frequency indicated semiconducting properties with the observed change in the conduction mechanism by increasing the temperature. The obtained low dielectric constant values could suggest using the entire ferrites in high-frequency applications such as microwave devices.

Impact of political violence on the mental health of school children in Egypt.

BACKGROUND: Since the beginning of the Egyptian political conflict, Tahrir Square has been the epicentre of intense political violence. Students attending schools located near this square witnessed and/or directly experienced the consequences of a series of violent events. AIM: This study will investigate the presence of psychiatric symptoms in children attending these schools to explore patterns of responses according to their perceptions of the revolution on their lives, adjusted for, gender and socio-economic status. METHOD: A descriptive cross-sectional study conducted with 515 Egyptian school children attending government, experimental, and private language schools located within 1 km of Tahrir Square. To assess psychiatric symptoms in these children, a specially designed questionnaire was used to detect, depression, anxiety, and post-traumatic stress disorder (PTSD) symptoms and impairments. RESULTS: Children attending schools near Tahrir Square showed high rates of depression, PTSD and anxiety symptoms. The risk factors identified for developing psychiatric symptoms were a negative perception of the effect of the revolution, knowing someone exposed to trauma during the events, female gender and low socio-economic class. DISCUSSION: These results highlight the need for large-scale studies to explore the consequences of ongoing political violence on children and to establish baseline data on the mental health of Egyptian children.

Prevalence of metabolic syndrome and cardiovascular risk factors among voluntary screened middle-aged and elderly Egyptians.

BACKGROUND: Central obesity and diabetes mellitus are recorded at high percentages among Egyptians. The aim of this study is to determine the prevalence of metabolic syndrome (MetS) and cardiovascular risk factors among a group of middle-aged and elderly Egyptians. METHODS: Our study included 220 middle-aged and senior Egyptians voluntary screened in an Egyptian private hospital with 800-bed capacity. Detailed medical history was obtained from all subjects, followed by clinical examination with weight and height measurement, body mass index calculation, waist hip ratio and arterial blood pressure measurement. Laboratory investigations done were complete blood picture, lipid profile and fasting blood glucose measurements. The diagnosis of MetS was based on the American Heart Association/Updated NCEP ATP III criteria. Cardiovascular risk assessment was calculated for each subject based on the Framingham/ATP III criteria. RESULTS: The prevalence of MetS in this study was of 55% among the whole sample, 85.6% among diabetics and 76.6% among hypertensive patients. Based on Framingham scoring system, 48.2% of the sample had moderate to high risk of developing cardiovascular disease. Odds ratio for patients with MetS for developing cardiovascular disease in the next 10 years was 2.8 (95% confidence interval: 1.6-4.8). CONCLUSION: The high prevalence of MetS among middle-aged and elderly Egyptians with the documented high prevalence of chronic diseases in Egypt calls for a nationwide screening program to detect MetS and tackle preventive strategies to face the epidemic of obesity and outcomes of MetS, particularly cardiovascular diseases.

Ocular manifestations in egyptian children and young adults with sickle cell disease.

In sickle cell disease (SCD), ocular lesions result from stasis and occlusion of small eye vessels by sickled erythrocytes. Vaso-occlusive disease of the retina can be responsible for nonproliferative (NPR) and proliferative retinopathy (PR). Patients are often asymptomatic until serious complications arise as, vitreous hemorrhage and retinal detachment. This work aimed to study the frequency and pattern of ocular manifestations in Egyptian children and young adults with SCD. In this cross-sectional study, 40 steady state patients (80 eyes) aged 2-28 years (30 children and 10 young adults) with established diagnosis of SCD (26 with homozygous SS and 14 with S/ß thalassemia underwent complete ophthalmic examination with dilated fundoscopy. Fluorescein angiography was performed for patients ≥12 years old. The overall frequency of retinal lesions was 47.5 % (46.2 and 50 % of SS and S/ß patients respectively). PR and NPR were evident in 32.5 and 27.5 % of all enrolled patients respectively (five patients having both). Peripheral retinal occlusion was a frequent ocular finding in both groups; the youngest patient showing PR was 15 years old. Older age, longer disease duration and splenectomy were significantly more prevalent among patients with PR. Despite lack of visual symptoms, children and young adults are at risk of PR. Frequency of retinal lesions was comparable in SS and S/ß patients. Periodic ophthalmologic examination starting at the age of 12 years is recommended for timely-identification of retinal lesions thus minimizing the risk of sight threatening retinopathy.

Mortality stastistics as indicators of quality of hospital care.

Death rates have always been important information for hospitals to provide a solid base for the evaluation of the quality of their medical care. This study was carried out to find out the gross death rate (GDR) as well as net death rate (NDR) in King Fahad hospital, Jeddah, Kingdom of Saudi Arabia (KSA) in the period from 1994-2000 and also to find out demographic characteristics of deaths in the year 2000 according to ICD-10 as indicators of quality of hospital care. Medical records of discharged patients including deaths during the year 2000 were reviewed (13386). Complete data about deaths were obtained. Results of the studied hospital showed gradual decrease in GDR from 5.8% to 4.5% (1994-1998) then slight increase from 4.9% to 5.0% (1999-2000) but still below the year 1994 (5.8%) and also there is gradual decrease in NDR from 4.6% to 3.6% in the studied period. GDR in different departments of the hospital during the year 2000 showed that Medical ICU was the highest (24.5%) followed by Surgical ICU (17.9%) followed by Cardiac ICU (14.3%) while GDR in the Medical department was found to be (12.9 %) of the discharged subjects. According to nationality; proportional mortality rate (PMR) of Saudis represented 62% of total deaths followed by Yemenis (8.2%) meanwhile Egyptians represented 3.7% of total deaths in the studied year. As concerned to age groups; the highest PMR was found among those aged 65-74 years (21.9%) while the lowest PMR was found among those aged 13-24 years (4.2%). The highest PMR of deaths during the studied year was reported in March (10.4%) followed by April (9.7%) then February (9.4%) which are the months of pilgrimage season while the lowest frequency was found in December (6.9%). Also PMR was found to be higher among females (57%) compared to males (43%). According to International Classification of Diseases (ICD-10); diseases of the circulatory system were found to be the commonest underlying cause of death in the studied year. It represented 35.5% of all deaths followed by neoplasms (11.2%) while the lowest cause reported was mental and behavioral disorders (0.1%). In conclusion, combination of the previous indicators and comparing the results with other hospitals in different countries indicates good quality of medical care in the studied hospital.