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Introduction: Addressing acquired laryngotracheal stenosis presents a complex healthcare dilemma. Results: We present a case series of 48 acquired post-intubation laryngotracheal stenosis cases managed within our Department of ENT Surgery at Farhat Hached Tunisia. Diagnosis relied on imaging and endoscopic findings. Among these cases, 28 exhibited tracheal stenosis, with 60% falling into grade 2–3 severity. Management approaches included sole endoscopic dilation for 17 patients, surgical intervention for 19 patients, and T-tube placement for 10 patients. Conclusions: The management of laryngotracheal stenosis poses a challenge for ENT surgeons. Prevention is paramount, encompassing various measures such as employing high-volume, high tracheostomy, and extended intubation practices. [ABSTRACT FROM AUTHOR]

The impact of pressure on structural parameters, electronic structure and magnetic properties in MoS2 bulk material has been investigated using spin-polarized full-potential linearized augmented plane wave method in the Tran-Blaha-modified Becke-Johnson gradient approximation approach. Our findings at zero pressure in MoS2 bulk material are usually dealing with the obtainable experimental input. With increasing pressure, the lattice parameters of MoS2 bulk material are reduced, the material of interest has tendency to a metallic character and the total magnetic moment is increased non-monotonically in both spin-up and spin-down conduits. The impact of pressure on structural properties is more important vs. c-axis than a-axis. [ABSTRACT FROM AUTHOR]

The two-dimensional (2D) graphitic carbon nitride currently has attracted attention for his electronic structure and optical properties. It is a good candidate for photocatalytic applications. The graphitic carbon nitride has been successfully synthesis and characterized by XRD, FTIR and UV–Vis Spectroscopy. The influence of acids treatment on structural and optical properties of g-C3N4 has been examined. It was found that the treatment of g-C3N4 bulk by different acids shows a disorder in the structure of samples which affect the optical performance of material. For the determination of the contributions of each orbital to the valence band maximum and the minimum conduction band the electronic structure of g-C3N4 has been investigated by density functional theory. The theoretical investigation reveals that the lone pair state and the π bonding play an important role in the electronic structure of graphitic carbon nitride and favorites the absorption of the g-C3N4 in the visible light. The optical properties such as the extinction coefficient (k), the refractive index (n), the optical conductivity ( σ opt ), and the dielectric function (εr, εi) have been explored by DFT calculation and confirmed by the experimental results. [ABSTRACT FROM AUTHOR]

The impact of pressure on structural parameters, electronic structure and magnetic properties in MoS2 bulk material has been investigated using spin-polarized full-potential linearized augmented plane wave method in the Tran-Blaha-modified Becke-Johnson gradient approximation approach. Our findings at zero pressure in MoS2 bulk material are usually dealing with the obtainable experimental input. With increasing pressure, the lattice parameters of MoS2 bulk material are reduced, the material of interest has tendency to a metallic character and the total magnetic moment is increased non-monotonically in both spin-up and spin-down conduits. The impact of pressure on structural properties is more important vs. c-axis than a-axis. [ABSTRACT FROM AUTHOR]

Hybrid membranes consisting of sulfonated poly (ether sulfone) octyl sulfonamide (SPESOS) cast together with protonated montmorillonite (H-MMT, 1, 3, and 6 wt%) were fabricated and characterized. Fourier-transform infrared (FT-IR) spectra of the H-MMT/SPESOS composites confirmed that no chemical reactions occurred between the SPESOS and clay. X-ray diffractograms (XRD) showed a significant shift in the major peak of SPESOS at 2θ = 15.5° due to the incorporation of H-MMT. Furthermore, scanning electron microscopy (SEM) confirmed a homogeneous structure of the composite, and thermogravimetric analysis (TGA) results revealed that the addition of H-MMT promoted water absorption via the decrease in the loss of composite mass during evaporation. The SPESOS with H-MMT had higher water retention, contact angle, and proton conductivity values than pristine SPESOS. The proton conductivity of the hybrid membranes, however, improved at 100°C from 42 mS/cm in pure SPESOS to 787, 350, and 300 mS/cm for the 1, 3, and 6 wt% H-MMT hybrids, respectively. These results demonstrate that the incorporation of the H-MMT is a viable strategy to boost the performance of SPESOS to construct a possible membrane for applying in fuel cells. [ABSTRACT FROM AUTHOR]

An electrolytic membrane for fuel cell application was fabricated by blending sulfonated poly ether sulfone octyl sulfonamide (SPESOS) with montmorillonite (MMT) clay at different proportions (1 wt.%, 3 wt.%, and 6 wt.%). The structural functionality, surface morphology, and thermal stability of the resultant composite membranes were characterized using Fourier transform infrared spectroscopy, x-ray diffraction, scanning electron microscopy, and thermogravimetric analysis. Interestingly, the thermal properties of the composite membranes were improved compared to pristine SPESOS. Furthermore, proportions as low as 0.1 wt.% in the MMT/SPESOS composite membrane showed superior proton conductivity to the SPESOS membrane. Thus, we propose the MMT/SPESOS composite membrane as a promising material for the electrolytic membrane in fuel cells at temperatures above 100°C. [ABSTRACT FROM AUTHOR]

BiFeO3 is the model multiferroic material widely considered as nanoparticles for its potential photocatalytic activity. In this work, we study the influence of annealing temperature on the structural, morphological and optical properties of BiFeO3 nanoparticles prepared by a facile chemical route and, the resulting photodegradation of Eosin B dye. When annealing temperature as low as 600 °C is used, some parasitic phases such as Bi2Fe4O9 appear in addition to the BiFeO3 phase. At the same time, the energy of the absorption onset and band gap shifts down and the photocatalytic activity toward Eosin B dye significantly increases by ∼27% when UV light is used while only a small if any, enhancement is observed in case of sunlight illumination. This photocatalytic enhancement could be therefore essentially attributed to the presence of secondary parasitic phases that could also explain previous reported observations. Furthermore, annealing at 500 °C to obtain pure parasitic-phase-free BiFeO3 nanopowder reveals excellent photodegradation of Eosin B reaching 95% efficiency after 40 min under sunlight illumination with good photostability after three consecutive degradation cycles. [ABSTRACT FROM AUTHOR]

Various proportions of sepiolite clay (1, 3, and 6 wt%) were blended with sulfonated polyether sulfone octyl sulfonamide (SPESOS) to improve the proton conductivity of SPESOS. Fourier-transform infrared spectroscopy, X-ray diffraction (XRD), and thermo-gravimetric analysis (TGA) were used to evaluate the structural functionalities, morphologies, and thermal stability of the composite membranes. FT-IR spectra indicated that no chemical reactions take place between the SPESOS and the clay. A lower degree of crystallinity in the SPESOS composite than that in pristine SPESOS was observed by XRD diffractograms. As observed in TGA, the elaborated membranes promoted the absorption of water due to the existence of sepiolite in the SPESOS. The presence of sepiolite nanoarchitecture material within SPESOS was found to have higher water retention, contact angle, and proton conductivity values than pristine SPESOS. These results reveal that the composite membranes display good hydrophilic character and higher ion exchange capacity than pristine SPESOS. [ABSTRACT FROM AUTHOR]

Background: Pediatric neck masses are a common complaint in children. The most common etiologies include congenital lesions, lymphadenopathy, vascular malformations, inflammatory, and malignant lesions. Spontaneous sternocleidomastoid hematoma is exceptional in infant. Case presentation: We describe a case of spontaneous cervical hematoma diagnosed in a 4-month-old child. Past history did not reveal a neck trauma, a history of difficult labor, a bleeding disorder or a pertinent family history. The diagnosis was suspected based on the imaging features and confirmed after surgical removal. Conclusions: Sternocleidomastoid swelling is commonly encountered in infancy. Ultrasound still remains the initial modality of choice. The management modalities are controversial. [ABSTRACT FROM AUTHOR]

For the continuous Hankel wavelet transform, we define the two-wavelet localization operators and we study their L p – L q boundedness and compactness. We also show that these operators are in the Schatten-von Neumann class. [ABSTRACT FROM AUTHOR]

A series of MoS2 films were prepared by the chemical bath deposition method at different temperatures (60–80 °C). The film thicknesses range from 0.988 up to 10.25 µm. The films are polycrystalline. Vibrating sample magnetometer (VSM) was used to study the magnetic properties of these MoS2 films. The experiments were done at room temperature with the magnetic field applied in the film plane. The magnetization curves indicate the coexistence of ferromagnetism and diamagnetism. The saturation and remnant magnetizations, the coercive and saturation fields as well as the diamagnetic susceptibility have been measured and are discussed as a function of the film thickness and the synthesis temperature. A change in the magnetic anisotropy is observed, and the magnetization easy axis direction switches from in-plane to out-of-plane as the thickness increases. The magnetic properties are correlated with the structural ones. [ABSTRACT FROM AUTHOR]

Purpose: Primary immunodeficiencies (PIDs) are a large group of diseases characterized by susceptibility to not only recurrent infections but also autoimmune diseases and malignancies. The aim of this study was to describe and analyze the distribution, clinical features and eventual outcome of PID among Tunisian patients. Methods: We reviewed the record of 710 patients diagnosed with Primary Immunodeficiency Diseases (PIDs) from the registry of the Tunisian Referral Centre for PIDs over a 25-year period. Results: The male-to-female ratio was 1.4. The median age at the onset of symptoms was 6 months and at the time of diagnosis 2 years. The estimated prevalence was 4.3 per 100,000 populations. The consanguinity rate was found in 58.2 % of families. According to the International Union of Immunological Societies classification, spectrums of PIDs were as follows: combined T-cell and B-cell immunodeficiency disorders account for the most common category (28.6 %), followed by congenital defects of phagocyte (25.4 %), other well-defined immunodeficiency syndromes (22.7 %), predominant antibody deficiency diseases (17.7 %), diseases of immune dysregulation (4.8 %), defect of innate immunity (0.4 %) and complement deficiencies (0.4 %). Recurrent infections, particularly lower airway infections (62.3 %), presented the most common manifestation of PID patients. The overall mortality rate was 34.5 %, mainly observed with combined immunodeficiencies. Conclusion: The distribution of PIDs was different from that reported in Western countries, with a particularly high proportion of Combined Immunodeficiencies and phagocyte defects in number and/or function. More is needed to improve PID diagnosis and treatment in our country. [ABSTRACT FROM AUTHOR]

This paper addresses the analysis of a two-way semi-blind amplify-and-forward (AF) relay network, in which the relay node requires partial instantaneous channel state information (CSI) to amplify the received signals. First, we derive the expression of end-to-end signal-to-noise ratio in dual-hop transmissions over independent and not necessarily identically distributed Rayleigh fading channels. Based on the opportunistic AF selection relaying, we define bounds of some metrics such as average sum-rate and outage probability. Furthermore, we provide exact and approximate expressions for the average symbol error rate. The obtained results show that the performance of the proposed system decreases slightly while the processing complexity is reduced significantly compared to those of CSI-assisted AF relay schemes. In order to prove the exactness of the proposed analysis, a selection of numerical results is provided. [ABSTRACT FROM AUTHOR]

Adamantinoma of long bones is a malignant primitive bone tumor with epithelial origin, involving the tibia in a great majority of cases. It is a rare neoplasm with less than 200 cases reported in the world literature. The authors report four cases of tibial adamantinoma and describe the clinical, imaging and histologic features of this neoplasm with emphasis on preoperative imaging, surgical treatment and post-operative follow-up. [ABSTRACT FROM AUTHOR]

We reviewed retrospectively the results of 28 hips (25 patients) after revision of the femoral component with use of a cemented stem, because of aseptic loosening. The mean duration of follow-up was 4.43 years (range 2–12 years). Over the course of the study period, repeat revision was done in 4 hips after an average of 4.45 years. Three hips had a repeat revision of the femoral component because of aseptic loosening and one for a deep infection. The rate of loosening of the femoral component was 32.4% (9 hips) at an average of 5.22 years. The 5-year survival rate was 76.9% with mechanical failure as end point; and 90% with re-revision of femoral component because of aseptic loosening as end point. The cement mantle was the principal factor, which was significantly associated with a better survival rate of femur fixation ( P < 0.05). No correlation was noted between quality of bone loss at the time of revision, bone graft or the use of long stems, and the survival rate of femoral component. By improving the cementing technique and in selected patients, the use of cemented femoral stem could be a good alternative for aseptic loosening THA. [ABSTRACT FROM AUTHOR]

Bismuth sulfide thin films were prepared by chemical bath deposition using thiourea as sulfide ion source in basic medium. First, the effects of both the deposition parameters on film growth as well as the annealing effect under argon and sulfur atmosphere on as-deposited thin films were studied. The parameters were found to be influential using the Doehlert matrix experimental design methodology. Ranges for a maximum surface mass of films (3 mg cm−2) were determined. A well-crystallized major phase of bismuth sulfide with stoichiometric composition was achieved at 190 °C for 3 h. The prepared thin films were characterized using grazing incidence X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray analysis. Second, the bandgap energy value was found to be 1.5 eV. Finally, the thermal properties have been studied for the first time by means of the electropyroelectric (EPE) technique. Indeed, the thermal conductivity varied in the range of 1.20-0.60 W m−1 K−1, while the thermal diffusivity values increased in terms of the annealing effect ranging from 1.8 to 3.5 10−7 m2 s−1. [ABSTRACT FROM AUTHOR]