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terior approach.<br /><br /> In the last twenty years, the statement of the CO2 laser in laryngeal microsurgery has proved particularly useful in the surgical treatment of laryngotracheal stenosis. The Authors report their surgical experiences and discuss them considering the location, size and pathologic features of the disease. The aim of this study was to evaluate the results that may be obtained in the treatment of laryngotracheal stenosis by endoscopy using the CO2 laser, and analyze the advantages and limitations of surgical methods implemented.<br /><br /> It includes 128 patients treated from 1981 to 2016 by endoscopy using the CO2 laser.<br /><br /> The healing occurred in 121 of the 128 patients (94.5%); in the remaining 7 cases (5.5%) - 4 subjects (3.1%) with supraglottic cicatricial stenosis and 3 patients (2.3%) with widespread laryngotracheal stenosis - it had to integrate the technique of endoscopic surgery with a traditional surgery of recovery. In particular, it has observed as follows In supraglottic stenosis - oedematous forms healed wi affect the choice of surgical addresses to adopt in individual cases and the prognostic judgment.<br /><br /> Airway management, Airway problems, CO2 laser, Direct laryngoscopy, Endoscopy, External surgical approach, Laryngotracheal stenosis, Minimally invasive surgery, Montgomery Safe T-tube, Tracheal stenosis, Tracheostomy.<br /><br />Airway management, Airway problems, CO2 laser, Direct laryngoscopy, Endoscopy, External surgical approach, Laryngotracheal stenosis, Minimally invasive surgery, Montgomery Safe T-tube, Tracheal stenosis, Tracheostomy.<br /><br /> A 64-year-old woman presented to our emergency department during the outbreak of the covid-19 emergency in Italy with syncope, anosmia, mild dyspnoea and atypical chest and dorsal pain. A chest CT scan showed an acute type B aortic dissection (ATBAD) and bilateral lung involvement with ground-glass opacity, compatible with interstitial pneumonia. Nasopharyngeal swabs resulted positive for SARS-CoV-2. For the persistence of chest pain, despite the analgesic therapy, we decided to treat her with a TEVAR. Patient's chest and back pain resolved during the first few days after the procedure. No surgical or respiratory complications occurred and the patient was discharged 14 days after surgery.<br /><br /> By performing the operation under local anesthesia, it was possible to limit both the staff inside the operatory room and droplet/aerosol release. Since we had to perform the operation in a hemodynamics room, thanks to the limited extension of the endoprosthesis and the good caliber of the right vertebral artery we were able to reduce the risk of spinal cord ischemia despite the lack of a revascularization of the left subclavian artery.<br /><br /> A minimally invasive total endovascular approach allows, through local anesthesia and percutaneous access, to avoid surgical cut down and orotracheal intubation. This, combined with a defined management protocol for infected patients, seems to be a reasonable way to perform endovascular aortic procedures in urgent setting, even in a SARSCoV- 2 positive patient.<br /><br /> COVID-19, Dissection, TEVAR.<br /><br />COVID-19, Dissection, TEVAR.<br /><br /> Use of diagnostic tools with high predictive value for common biliary duct (CBD) obstruction has the potential to provide valuable information. This study aimed to examine the respective diagnostic values of biochemistry, abdominal ultrasonography (US), and magnetic resonance cholangiopancreatography (MRCP) in patients with suspected biliary obstruction.<br /><br /> A total of 119 patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) based on a suspicion of CBD obstruction were included. Patients also had data for biochemical and hematologic tests, abdominal US and MRCP. The respective sensitivity, specificity, negative predictive value, and positive predictive value of US, MRCP, and the laboratory parameters in the diagnosis of ERCP-confirmed CBD obstruction were estimated.<br /><br /> ERCP did not show obstruction in 15.1% of the cases. Based on 95% confidence intervals, MRCP had greater sensitivity than ultrasound in predicting obstruction (95% vs. 62%). In addition, ultrasound had a very high 31.9% false negative rate when compared to MR (4.2%). On the other hand, a combined approach had better diagnostic value. None of the laboratory parameters exhibited a predictive value. However, old age was significantly associated with biliary obstruction.<br /><br /> MRCP, particularly when combined with ultrasound, is a useful diagnostic tool for the diagnosis of common biliary duct obstruction and may have the potential to eliminate the need for further ERCP in some patients. On the other hand, US alone does not seem to have acceptable diagnostic value. Further large and prospective studies are warranted to draw firm conclusions.<br /><br /> Biliary Obstruction, Endoscopic Retrograde Cholangiopancreatography (ERCP), Magnetic Resonance Cholangiopancreatography (MRCP), Ultrasonography.<br /><br />Biliary Obstruction, Endoscopic Retrograde Cholangiopancreatography (ERCP), Magnetic Resonance Cholangiopancreatography (MRCP), Ultrasonography.This paper reports the synergistic effect of colloidal CdSe quantum dots (QDs) and PC61BM on the performance of ITO/ZnO QDs/PCDTBTPC61BMCdSe QDs/MoO3/Ag based ternary organic solar cells (OSCs). The MoO3 and ZnO QDs (∼2.87 nm) layers work as the transparent hole transport layer (HTL) and electron transport layer (ETL), respectively. The CdSe QDs (∼4.58 nm) are blended with PC61BMPCDTBT binary solution to improve the optical properties and charge transportation. Significant photoluminescence (PL) quenching is observed when part of the PC61BM is replaced by CdSe QDs with equivalent weight in the PCDTBT. The proposed ternary OSC gives an open-circuit voltage of 854 mV, a short circuit current density of 14 mA cm-2, fill factor of 42% and power conversion efficiency (PCE) of 5.02%. The PCE of the ternary OSC is increased by more than 38% compared to the binary OSC. This significant improvement in the performance parameters is attributed to the enhanced absorption and higher transportation of photo-generated charge carriers, as well as the increased charge dissociation due to the synergistic effect of CdSe QDs and PC61BM. The external quantum efficiency is also enhanced significantly in the ternary OSC due to the better conversion of solar energy into electrical energy.The structural and magnetic behavior of Mn-site doped intermetallic manganese silicide alloys of nominal compositions Mn5-x A x Si3 (x = 0.05, 0.1, 0.2 and A = Ni, Cr) have been investigated with a focus to the inverted hysteresis behavior and thermomagnetic irreversibility. Room temperature x-ray powder diffraction data confirm that all the doped alloys crystallize in hexagonal D88 type structure with space group P63/mcm. The doped alloys are found to show paramagnetic-collinear antiferromagnetic (AFM2)-noncollinear antiferromagnetic (AFM1) transitions during cooling from room temperature. A significant decrease in the critical values of both AFM1-AFM2 transition temperatures and fields have been observed with the increasing Ni/Cr concentration. Inverted hysteresis loop, field-induced arrest, and thermomagnetic arrest, the key features of the undoped Mn5Si3 alloy, are found to be significantly affected by the Mn-site doping and eventually vanishes with 4% doping.Developing cost-effective, highly active, and stable electrocatalysts for boosting electrochemical hydrogen evolution reaction (HER) in alkaline media is playing a critical role in meeting the demands of the hydrogen industry in the future. Herein, an efficient HER electrocatalyst based on flowerlike S-doped Ni2P mesoporous nanosheets (NSs) supported on nickel foam (S-Ni2P NSs/NF) was developed through an effective approach. The obtained S-Ni2P NSs/NF catalyst required low overpotential of only 87.5 and 179.1 mV to reach a current density of 10 and 50 mA cm-2, respectively. Moreover, a small Tafel slope of 62.1 mV dec-1 for S-Ni2P NSs/NF demonstrated that the HER process occurred with very fast kinetics. Besides high HER activity, the synthesized S-Ni2P NSs/NF catalyst exhibited superior stability and long-term durability towards HER, which had the ability to operate for over 30 h without degradation in catalytic performance. The unique flower-like nanosheet structure with excellent mesoporous characteristics of S-Ni2P NSs/NF resulted in maximizing the electrochemical active surface area for providing a large number of electrocatalytic active sites. In addition, the S-doping effect could modulate the electronic structure of Ni species in Ni2P, leading to an acceleration of the adsorption rate of reaction intermediates on the surface of catalysts towards improving HER kinetics. The results not only demonstrate S-Ni2P NSs/NF as an active catalyst for HER, but offer an effective strategy for improving the catalytic activity of earth-abundant transition metal-based HER catalysts.Two-dimensional (2D) InSe, which exhibits high electron mobility and a wide band gap has emerged as a promising material for photoelectric and thermoelectric applications. The inadequate understanding of the lattice thermal conductivity (κ), however, hampers the advancement of 2D InSe. Herein, by taking into account anharmonicity up to the fourth order and introducing the equibiaxial tensile strain (ϵ), we have performed an in-depth study on the lattice dynamics of 2D InSe. [https://www.selleckchem.com/products/Nanchangmycin.html selleck products] Interestingly, the κ exhibits a non-monotonic behaviour as a function of equibiaxial tensile strain, which can be attributed to the changes in acoustic phonon lifetimes. At the Γ point, a blue-shift of the lowest optical mode and a red-shift of the uppermost optical mode are reported for the first time. More strikingly, the blue-shift can be largely suppressed by equibiaxial tensile strain. Further study indicates that the unique transition of the potential energy surface is responsible for the disappearance of the blue-shift. Our work may enlighten the future research on phonon engineering and management of the lattice thermal conductivity of 2D InSe.Magnetic ferrite materials have been extensively studied for a range of technological applications, such as magnetic motors, recording media, and millimetre-wave devices. In this context, the nanosized epsilon phase of Fe2O3 (ϵ-Fe2O3) attracts significant attention due to its high coercive field at room temperature. Here, we report the in-situ aerogel nanoreactor growth of magnetic ϵ-Fe2O3 nanoparticles, exhibiting a coercive field (Hc) of 4000 Oe. We show that the control of nanoreactor plays an important role in the growth of ϵ-Fe2O3 nanoparticles. The findings provide a versatile reaction pathway for the growth of magnetically hard ferrite nanoparticles.In this work, we report an ultra-high sensitive (S = 1.4 × 108%), prompt response and recovering Pt/Pt+SiO2 cermet layer/GaN-based hydrogen (H2) sensor. A sensor fabricated with a 15 nm cermet layer, comprising Pt and SiO2, deposited between 15 nm Pt and GaN layers, exhibits significantly enhanced sensitivity in the detection of 4 %H2 by ≈ 300×, as compared to the reference Pt/GaN sensor at ambient temperature (300 K). Furthermore, the sensitivity of the our sensor shows very weak dependence on temperature (T) with maximum sensitivity ([Formula see text]) reducing from 1.4 × 108% to 2.3 × 107% as temperature increases from 300 to 423 K. The shift in the threshold voltage of the test sensor (ΔV t,test = 767 mV) increases by 50 % as compared to the shift in threshold voltage of the control sensor (ΔV t,control = 511 mV) at 1 mA/cm2. In addition, the cermet sensor also demonstrates fast response/recovery time, which reduces from 4.58 (2.36) seconds to 94 (39) milliseconds as the temperature increases from 300 to 423 K.