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This paper contributes to the design of a modified rectangular-shaped metamaterial with a tri-band coverage for reflection and transmission coefficients. Two symmetrical rectangular split ring resonators (SRR) were carefully engineered and then connected by their edges along the axis (Ox) with a substantial C-shaped structure, experiencing the peak surface current value near the magnetic resonances, causing the proposed unit cell to resonate at 5.73 GHz, 8.67 GHz, and 13.78 GHz, where it exhibited negative effective permittivity (ENG), permittivity and permeability (DNG), and permeability (MNG), respectively. A total of 6 × 6 mm2 modified SRR was printed on Rogers RO3006 to achieve a better effective medium ratio (EMR) in the C band (4.55-6.27 GHz), X band (7.81-9.45 GHz), and Ku band (13.15-14.37 GHz), respectively. A comprehensive parametric analysis was performed to illustrate the effect of crucial parameter h on the scattering parameters (S11, S21) of the metamaterial resonant structure (MRSRR) in the specified frequency ranges. Structure underwent additional testing with 1 × 2, 2 × 1, 2 × 2, and 4 × 4 arrays, yielding results that demonstrated sufficient concordance for consideration in the C band [4-8 GHz], X band [8-12 GHz], and Ku band [12-18 GHz] satellite applications. Computer Simulation Technology (CST) Microwave Studio was utilized to reach the scattering parameters and their effective medium characteristics, specifically permittivity and permeability, via the Nicolson–Ross–Weir (NRW) approach, executed through MATLAB code. The surface current was examined, and the corresponding circuit model was confirmed utilizing the Advanced Design System (ADS) software, with results compared against the CST simulation outcomes.

In this study, a green method was employed for dyeing silk and cotton fabrics using extracts from Beta vulgaris peels as a colorant, pomegranate rind as a bio-mordant, and microwave-assisted extraction as a green extraction technique. The dyeing process was optimized employing response surface methodology and characterization of the dyed fabric was conducted using FTIR, SEM, color strength, and fastness properties. The optimized conditions for dyeing were a solvent-to-extract ratio of 10 ml/g, temperature 70°C, and pH 6. The values of K/S calculated under optimal conditions were 2.565 for cotton fabric and 3.928 for silk fabric, with good fastness properties ranging from 4-5. Better fastness properties were obtained at low pH and a high solvent-to-solid ratio. FTIR confirmed the different functional groups including prominent peaks appearing at 1600–1700, 1546, and 1200–1300 cm −1 for Amide-I, amide-II, and amide-III functional groups in silk and 3271–3332 cm −1 (OH stretching), 2851–2915 cm −1 (C–H stretching) for cotton fabric. SEM analysis showed the characteristics of the fabric surface before and after the adsorption of the dye components. The current study revealed selected bio-waste as a new and cheaper source of coloring material. Natural dye obtained from different waste materials can be exploited as a dyeing tool for different fabrics on an industrial scale, providing a viable green alternative to hazardous synthetic colorants.

Summary: In the present study, bimetallic oxides comprising nickel (Ni) and cobalt (Co) were synthesized using a facile hydrothermal method in the presence of CTAB and L-lysine. Their efficacy in catalyzing hydrogen production under alkaline conditions was assessed. Structural, vibrational, and morphological characteristics were analyzed utilizing X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) techniques. The SEM images revealed a needle-like shape which is due to the surfactant addition. The NiCo oxides exhibited the lowest onset potential of 83 mV for HER and 130 mV for OER under standard conditions. The catalysts needed a potential of 286 and 450 mV to attain a current density of 50 mA/cm2 along with Tafel slope values of 119 and 332 mV/dec for HER and OER, respectively. These results suggested that L-lysine as a surfactant is highly effective in the fabrication of NiCo bimetal oxides for electrolytic water splitting applications.

ABSTRACT The prevalence of infections caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (ESBL-EC) and carbapenemase-producing E. coli (CP-EC) is increasing worldwide. We investigated the epidemiology of ESBL-EC and CP-EC causing hospital-acquired (HA) infections in a large teaching hospital in Tunisia over the last two decades and compared it with a collection of 107 community-acquired (CA) ESBL-EC isolates. Between 2001 and 2019, the incidence of HA ESBL-EC increased significantly from 0.08 to 0.32 cases per 1,000 patient days, due entirely to the rapid emergence and expansion of ST131, which accounted for 42.3% (157/371) of HA ESBL-EC. Most ESBL-EC harbored the CTX-M type (92%) with a predominance of blaCTX-M-15. The C2/H30-Rx subclone (n = 103, 65.6%) accounted for 90% of ST131 isolates between 2003 and 2012 and was exclusively associated with CTX-M-15, whereas cluster C1-M27, which was associated with CTX-M-27, emerged in 2013 and expanded gradually to 55% of ST131 in 2019. ST131 prevalence was higher among CA ESBL-EC than HA ESBL-EC (63.6% vs. 42.3%, P = 0.002). CA C2 subclone and non-ST131 isolates showed higher virulence scores than HA isolates. The incidence of CP-EC remained stable over the study period with a mean of 0.08 cases per 1,000 patient days. Among the 38 identified CP-EC isolates, only 16.2% belonged to the ST131 clone and 81.5% produced OXA-48-like carbapenemases. ST131 is the major driver of ESBL-EC spread in both hospital and community settings in Tunisia, mainly linked to the expansion of the CTX-M-15-C2 and CTX-M-27-C1 subclades. The emergence of CP-EC requires ongoing genomic surveillance.IMPORTANCEWe aimed to investigate the microbiological features of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (ESBL-EC) and carbapenemase-producing E. coli (CP-EC) causing hospital- and community-acquired infections in Tunisia over the last two decades. The study captured the emergence and expansion of the CTX-M-15-C2 ST131 subclade and successively the CTX-M-27-C1 ST131 subclade, which were responsible for the steady increase in the prevalence of ESBL-EC. However, the incidence of CP-EC remained stable over the study period with a highly diverse content in carbapenemase genes dominated by blaOXA-48-like. This is the first study to provide comprehensive data on the epidemiology of ESBL-EC and CP-EC in a North African country.

Polycystic ovary syndrome (PCOS) is a common condition. Its pathophysiology involves an interaction between genetic and environmental factors, resulting in different reproductive and metabolic subtypes. Genetic variation in the angiotensin converting enzyme (ACE) gene has been implicated in the pathophysiology of the syndrome. Our project aims to investigate the relationship between the ACE I/D (insertion/deletion) polymorphism and circulating levels of ACE activity, renin and aldosterone in PCOS. Patients and methods: PCOS and healthy donors were enrolled over 2 years. The Rotterdam criteria were used to segregate 4 phenotypes. Enrolled controls were matched to PCOS patients for body mass index. Clinical data were recorded and blood samples were taken for analysis of ACE I/D polymorphism and biochemical parameters. Hardy-Weinberg equilibrium evaluation, mean/median comparison and Spearman correlation were performed. Results: A total of 102 women with PCOS and 107 controls were involved in the study. The most common polymorphism was ID, both in the control and PCOS groups. Renin levels in PCOS patients were positively correlated with luteinizing hormone (LH) and anti-mullerian hormone (AMH) in the ID genotype and with testosterone, free androgen index and insulin in the DD genotype. Conclusion: The ACE I/D variation may influence the pathophysiology of PCOS subtypes, together with an indirect relationship with renin. Our findings may provide valuable therapeutic insights into the management of PCOS, particularly regarding the potential need for ACE inhibitors or renin inhibitors tailored to ACE gene I/D genotypes or specific subtypes.

Purpose Allgrove syndrome, also known as “triple A” syndrome, is characterized by adrenal insufficiency, achalasia, and alacrimia. When neurological signs are also present, the condition is referred to as “4 A” syndrome. Methods We conducted a retrospective analysis of three patients with 4 A syndrome confirmed genetically. A complete neurological exam was carried out by an experimented neurologist. Results Herein, we describe the neurological characteristics often associated with this condition, through the clinical and electrophysiological analysis of three patients. All patients exhibited a mutation in AAAS, the gene coding for ALADIN. While these individuals presented with the classic features of triple-A syndrome, neurological symptoms were not prominent. Conclusion The neurological manifestations of Allgrove syndrome have historically been overlooked and inadequately explored. Due to the condition’s rarity and substantial phenotypic heterogeneity, only recently have a variety of symptoms been recognized and described.

An eco-friendly synthetic route was developed for the formation of nickel oxide (NiOaq and NiOet) nanoparticles (NPs) by treating Ni(NO3)2.6H2O with aqueous/ethanolic extracts of Elettaria cardamomum leaves; the same reaction was performed in the presence of graphene oxide (GO) to produce NiOaq@GO and NiOet@GO nanocomposites (NCs), respectively. The NMs were characterized by XRD, FT-IR, SEM, EDX, UV–visible spectroscopy, and TGA-DSC analysis. They were also subjected to electrochemical investigations and photocatalytic degradation of crystal violet (CV) dye. XRD analysis revealed the average crystallite sizes of 8.84–14.07 nm with a face-centered cubic form of NiO NPs and a hexagonal structure of their nanocomposites with GO. FT-IR spectroscopy confirmed the presence of Ni-O vibrations at 443-436 cm−1. SEM images confirmed the spherical morphology of NiO NPs while NiOaq@GO NCs contained randomly aggregated, thin, and wrinkled graphene sheets. NiOaq and NiOet have shown particle sizes of 27.7–30.63 nm which were decreased to 19.33–26.39 nm in their respective NiOaq@GO and NiOet@GO NCs. EDX spectra verified the homogeneous distribution of elements (Ni, O, C) on the surface of the particles. The synthesized NCs have shown smaller band gaps (NiOaq@GO = 3.74 eV; NiOet@GO = 3.34 eV) as compared to their respective NPs (NiOaq = 5.0 eV; NiOet = 3.89 eV). TGA/DSC data was used to find the thermal stabilities, glass transition temperatures, and enthalpies. Cyclic voltammetry measurements exhibited distinct oxidation and reduction peaks. NCs exhibited better potential as electrode materials for supercapacitor applications as compared to their respective NPs. NiOet@GO exhibited the best electrochemical performance and photocatalytic degradation efficiency of CV dye. After 120 min exposure to sunlight, the degradation coefficient of CV was observed to be 82.93, 86.34, 89.99, 90.27 and 81.65 % in the presence of NiOaq, NiOet, NiOaq@GO, NiOet@GO and GO, respectively.

The vein of Galen aneurysmal malformation is a rare congenital malformation of the cerebral blood vessels. It is a result of the persistence of an embryonic vessel that drains multiple arteriovenous shunts. This malformation can cause a multitude of symptoms ranging from cardiac failure to headaches depending on the age of presentation. In the fetus, cardiac manifestations are rare and are linked to a very poor prognosis. That’s why prenatal diagnosis is crucial in early detection and management. We present a case of a vein of Galen aneurysmal malformation, diagnosed prenatally with ultrasonography. The newborn developed widely a high-output cardiac failure. Prenatal diagnosis facilitates the early detection of this malformation as well as predicting the prognosis.

PurposeSocial media (SM) has become a common activity for today’s young people. It is sometimes overused and potentially results in SM addiction. This study aims to assess SM addiction and its associated factors in medical students and to examine its relationship with dimensions of personality global self-esteem, and social self-esteem.Materials and methodsWe carried out a cross-sectional study among a sample of medical students in the region of Sfax in Tunisia. Social Media Addiction Scale-Student Form (SMAS-SF), Big Five Inventory, Rosenberg Self-Esteem Scale, and Social Self-Esteem Inventory were used to collect data.ResultsOverall, 116 medical students were included in the survey. The median age of the participants was 26 years, and 91 students (78.4%) were female. Almost half of them (55.20%) were enrolled in the third cycle. The most widely used SM was Facebook (98.3%). Students with the highest SMAS-SF scores had a significantly younger age of first use (p=0.011, r=-0.235), spent more time on their favorite SM (p=0.005, r=0.260), and performed more activities on SM, namely: making comments (p=0.005), browsing SM profiles (p=0.018), and posting videos (p=0.007) or pictures (p=0.002). The need to establish an identity was significantly associated with higher SMAS-SF scores (p=0.011). We also found that neuroticism and a low level of conscientiousness were linked to high SMAS-SF scores (p=0.006, r=0.252 and p=0.050, r=-0.183, respectively). Moreover, high SMAS-SF scores were significantly related to lower global and social self-esteem scores (p=0.015, r=-0.226 and p=0.032, r=-0.199, respectively).ConclusionOur results highlight the critical need to take into consideration the evaluation and intervention of self-esteem and personality dimensional issues to target interventions for SM addiction among medical students.