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Undoped PVA and Zinc iodide (ZnI2) inorganic salt doped PVA with different ZnI2 (1–37) wt% percentages are novel composite polymer dielectric films have been successfully prepared by the solution cast method. The developed dielectric films were characterized by analyzing the physicochemical phenomenon to study the effect of ZnI2 inorganic salt concentrations. The XRD histogram explicated the being semi-crystalline nature of PVA polymeric matrix with ZnI2 inorganic salt doping. The optical UV–Vis–NIR characteristics of the composite dielectric films were measured. The effect of ZnI2 inorganic salt loading contents increasing on opto-electrical properties such as transmittance, Absorbance, optical band gap in addition to the AC impedance spectroscopy was studied in the polymer composite dielectric film. The modifications in the optical properties of PVA film are attributed to the interaction between the salt molecules and the PVA matrix. The frequency dependent AC\DC electric conductivity at different ZnI2 content follows and obeyed the Jonscher's universal power law. The data of AC impedance spectroscopy is to map ready the complex generalization of resistance that includes capacitive and inductive effects of the polymer composite dielectrics as a function of the angular frequency. These films with excellent optoelectronic phenomenon beside appreciable flexibilities aid their claims as multifunctional UV shielding devices with enhanced a character of semiconductors. [ABSTRACT FROM AUTHOR]

Electrical and switching property of amorphous defect chalcopyrite ZnGa2Te4 thin films prepared by thermal evaporation technique has been studied. The elemental chemical compositions of the prepared bulk as well as the as-deposited film were determined by means of energy dispersive X-ray spectrometry. X-ray diffraction pattern revealed that the powder compound is polycrystalline and the as-deposited and the annealed films at t ≤ 548 K have the amorphous phase, while that the annealed at t ≥ 573 K are polycrystalline with a single phase of a defect chalcopyrite structure similar to that of the synthesized material. The great advantage of this material is the capability to appear in two different phases, the amorphous and the crystalline phases, with rather different electrical properties. Both dynamic and static I-V characteristics and the switching phenomenon at 601 nm are investigated. The threshold switching mechanism was explained by a thermal model of switching, i.e., joule heating with an electrically conducting channel. ZnGa2Te4 is good candidate in phase change memory device. [ABSTRACT FROM AUTHOR]

The impedance characteristics of the nanostructure p-ZnGa2Se4/n-Si heterojunction diode were investigated by impedance spectroscopy method in the temperature range (303-503 K) and the frequency range (42 Hz -5 MHz). The real and imaginary parts of the complex impedance are changed with the frequency. Both are decreased with increasing temperature at the lower frequencies and are merged at the higher frequencies. The dielectrical relaxation mechanism of the diode was analyzed by the Cole-Cole plots. The Cole-Cole plots under various temperatures exhibit one relaxation mechanism. With increasing temperature, the radius of the Cole-Cole plots decreases, which suggests a mechanism of temperature-dependent on relaxation. [ABSTRACT FROM AUTHOR]

AgGa0.5In0.5Te2 thin films were deposited, by thermal evaporation of presynthesised bulk ingot material, onto a Corning 7095 glass substrates. EDXS studies on the prepared films show that the as-deposited films are nearly stoichiometric. Also, XRD studies on the as-deposited and annealed films revealed an amorphous-to-crystalline phase transition at Ta ≈ 473 K. The optical constants (n, k) of the amorphous and crystalline AgGa0.5In0.5Te2 films, were determined from the transmittance and the reflectance data at normal incidence in the spectral range 400-2500 nm. The high frequency dielectric constant and the carrier concentration and the effective mass ratio were determined from the analysis of the refractive index at long wavelengths. The analysis of the absorption spectra of the investigated films revealed non-direct energy gaps, characterizing the amorphous films, in contrary to the crystalline films which exhibited only direct energy gaps. [ABSTRACT FROM AUTHOR]

Silver mercury iodide thin films (Ag2HgI4) were successively deposited onto pre-cleaned glass substrates at room temperature by chemical bath deposition at different deposition times producing films of different thicknesses. The elemental composition of the as-deposited films measured by energy dispersive X-ray analysis shows the formation of stoichiometric Ag2HgI4 thin films. X-ray diffraction patterns reveal that Ag2HgI4 films are single phase of a polycrystalline structure, and have a dominant diffraction along [111] direction. The structure of the films was further investigated by transmission electron microscope verifying the polycrystalline nature of samples and nearly matching with X-ray diffraction data. The FESEM images reveal dense and well-defined grains. The optical properties of as-deposited films have been calculated from the recorded transmission and reflection data in the spectral range 400-2500 nm. The analysis of the optical absorption coefficient indicates the presence of direct and indirect optical transition whose values decrease with the increase of thickness, while the values Urbach energy follow is a reverse behavior. The study of optic parameters of 558 nm thick film heated at 330 K was also investigated. The electrical conductivity was measured by four-probe experiment in the range from 300 to 500 K. The activation energy was found to nearly equal half of the direct band gap indicating the intrinsic conduction of studied films is dominant. [ABSTRACT FROM AUTHOR]

Objective: The study aims to explore smokers' acceptance of using a conceptual cigarette tracker like a cigarette filter for smoking cessation using the Technology Acceptance Model (TAM). Smokers presenting to the family medicine clinics at a tertiary care center were asked to complete an anonymous questionnaire., Results: A total of 45 participants were included. Two-thirds of the smokers reported that they would like to try such a tracker and perceived its usefulness in reducing the number of daily cigarettes consumed and increasing the motivation to join a smoking cessation program. A range of 40-50% of the participants had a neutral attitude towards the visibility of the tracker and its effect on social acceptance and self-image. The structural equation model with latent variables path analysis showed that only perceived usefulness correlated to the intention to adopt with statistical significance. Visibility was correlated with intention to adopt with a marginal p-value of 0.061. Driven by perceived usefulness, smokers may buy or try a cigarette tracker for smoking reduction or cessation., (© 2022. The Author(s).)

Introduction: Synthol injection for body contouring has been used by bodybuilders for some time. We report two extremely rare systemic complications; pulmonary granulomatosis and hypercalcemia, in a woman who has received Synthol injections for buttocks augmentation., Presentation of Case: The case discussed in this report is of a 36-year-old lady who presented for severe hypercalcemia and nephrocalcinosis. Subsequent workup revealed granulomas in the buttocks and in the lungs. Upon questioning, it was discovered that she had received Synthol injection for buttocks augmentation a few months earlier. Labs were consistent with calcitriol mediated hypercalcemia, a phenomenon observed in granulomatous diseases. A diagnosis of foreign body granulomatosis with pulmonary migration and secondary hypercalcemia was made. The patient was started on prednisone and showed an initial positive response., Discussion: Reported complications of Synthol include pain, muscle deformity, and ulceration at the injection site. Hypercalcemia secondary to foreign body granulomatosis after Synthol injection has been reported only once previously, and here we report a second case. The hypercalcemia is thought to be calcitriol mediated, where overexpression of CYP27B1 in the macrophages forming the granulomas leads to pathological extrarenal calcitriol production. Pulmonary granulomatosis, theorized to be secondary to hematologic migration of the injected material, has never been reported previously with Synthol use., Conclusion: Synthol injection for body contouring may be a cause of extensive local and pulmonary foreign body granulomatosis leading to calcitriol mediated hypercalcemia. History of cosmetic injections should not be disregarded during history taking., Competing Interests: The authors report no conflict of interest with any parties in regards to this research article., (© 2021 The Author(s).)

Erectile dysfunction (ED) is increasingly becoming more common in young healthy males and is attributed mainly to psychogenic causes in these patients. Recent studies have reported that ED could be secondary to pudendal nerve or artery entrapment. This perspective assessed the efficacy of laparoscopic pudendal nerve and artery decompression in young patients suffering from refractory ED, associated to a pudendal nerve entrapment syndrome. After excluding patients with psychological ED and venous leakage, five young male patients with a history of both ED and pudendal nerve entrapment syndrome diagnosed based on the Nantes criteria were recruited. Pudendal nerve and artery release was performed using a laparoscopic transperitoneal approach. International Index for Erectile Function (IIEF-5) and erectile hardness score (EHS) improved significantly in all patients, 3 months after surgery. Pudendal nerve and artery entrapment could be therefore a reversible cause of ED in young healthy males, and its treatment by laparoscopic pudendal nerve and artery decompression seems to be safe and effective.

Following the Syrian conflict that began in 2011, Lebanon received more than one million refugees including 44,000 Palestinian refugees from Syria (PRS). PRS children were integrated into existing schools run by the United Nations Relief and Works Agency (UNRWA). Despite efforts by UNRWA to integrate the newly displaced into its services in Lebanon, only 58% of 6-18-year-old PRS children were enrolled in school in 2014. Informed by ecological systems theory, we examined the role of parental characteristics in determining school enrollment among PRS children following displacement into Lebanon. Utilizing data from the 2014 UNRWA Vulnerability Assessment ( N  = 12,378 6-18-year-old children), we specified crude and adjusted logistic regression models to predict child school non-enrollment including a set of variables on head of family characteristics (gender, age, education, and presence/absence of chronic disease) and post-displacement household characteristics (crowding, wealth, camp residence, region, and type of dwelling). The results show that, adjusting for household characteristics, a child living in a family whose head has secondary education or higher is more likely to be enrolled in school compared to one living in a family headed by someone with less than secondary education. Parental education remains the strongest predictor of child school enrollment despite displacement-related household disadvantage. To break the cycle of intergenerational educational disadvantage, it is critical for UNRWA to proactively design school retention programs for PRS children living in families whose head had limited access to education., Supplementary Information: The online version contains supplementary material available at 10.1007/s12134-020-00793-y., (© The Author(s), under exclusive licence to Springer Nature B.V. part of Springer Nature 2021.)

Background: Recognizing low right ventricular (RV) function from 2-dimentiontial echocardiography (2D-ECHO) is challenging when parameters are contradictory. We aim to develop a model to predict low RV function integrating the various 2D-ECHO parameters in reference to cardiac magnetic resonance (CMR)-the gold standard., Methods: We retrospectively identified patients who underwent a 2D-ECHO and a CMR within 3 months of each other at our institution (American University of Beirut Medical Center). We extracted three parameters (TAPSE, S' and FAC RV ) that are classically used to assess RV function. We have assessed the ability of 2D-ECHO derived parameters and clinical features to predict RV function measured by the gold standard CMR. We compared outcomes from four machine learning algorithms, widely used in the biomedical community to solve classification problems., Results: One hundred fifty-five patients were identified and included in our study. Average age was 43±17.1 years old and 52/156 (33.3%) were females. According to CMR, 21 patients were identified to have RV dysfunction, with an RVEF of 34.7%±6.4%, as opposed to 54.7%±6.7% in the normal RV population (P<0.0001). The Random Forest model was able to detect low RV function with an AUC =0.80, while general linear regression performed poorly in our population with an AUC of 0.62., Conclusions: In this study, we trained and validated an ML-based algorithm that could detect low RV function from clinical and 2D-ECHO parameters. The algorithm has two advantages: first, it performed better than general linear regression, and second, it integrated the various 2D-ECHO parameters., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/cdt-20-471). HI serves as an unpaid editorial board member of Cardiovascular Diagnosis and Therapy from Jul 2019 to Jun 2021. The other author has no conflicts of interest to declare., (2020 Cardiovascular Diagnosis and Therapy. All rights reserved.)

Objectives. In heart failure, invasive angiography is often employed to differentiate ischaemic from non-ischaemic cardiomyopathy. We aim to examine the predictive value of echocardiographic strain features alone and in combination with other features to differentiate ischaemic from non-ischaemic cardiomyopathy, using artificial neural network (ANN) and logistic regression modelling. Design. We retrospectively identified 204 consecutive patients with an ejection fraction <50% and a diagnostic angiogram. Patients were categorized as either ischaemic ( n  = 146) or non-ischaemic cardiomyopathy ( n  = 58). For each patient, left ventricular strain parameters were obtained. Additionally, regional wall motion abnormality, 13 electrocardiographic (ECG) features and six demographic features were retrieved for analysis. The entire cohort was randomly divided into a derivation and a validation cohort. Using the parameters retrieved, logistic regression and ANN models were developed in the derivation cohort to differentiate ischaemic from non-ischaemic cardiomyopathy, the models were then tested in the validation cohort. Results. A final strain-based ANN model, full feature ANN model and full feature logistic regression model were developed and validated, F 1 scores were 0.82, 0.79 and 0.63, respectively. Conclusions. Both ANN models were more accurate at predicting cardiomyopathy type than the logistic regression model. The strain-based ANN model should be validated in other cohorts. This model or similar models could be used to aid the diagnosis of underlying heart failure aetiology in the form of the online calculator (https://cimti.usj.edu.lb/strain/index.html) or built into echocardiogram software.

Purpose: Prostate cancer care in the Middle East is highly variable and access to specialist multidisciplinary management is limited. Academic tertiary referral centers offer cutting-edge diagnosis and treatment; however, in many parts of the region, patients are managed by non-specialists with limited resources. Due to many factors including lack of awareness and lack of prostate-specific antigen (PSA) screening, a high percentage of men present with locally advanced and metastatic prostate cancer at diagnosis. The aim of these recommendations is to assist clinicians in managing patients with different levels of access to diagnostic and treatment modalities., Methods: The first Advanced Prostate Cancer Consensus Conference (APCCC) satellite meeting for the Middle East was held in Beirut, Lebanon, November 2017. During this meeting a consortium of urologists, medical oncologists, radiation oncologist and imaging specialists practicing in Lebanon, Syria, Iraq, Kuwait and Saudi Arabia voted on a selection of consensus questions. An additional workshop to formulate resource-stratified consensus recommendations was held in March 2019., Results: Variations in practice based on available resources have been proposed to form resource-stratified recommendations for imaging at diagnosis, initial management of localized prostate cancer requiring therapy, treatment of castration-sensitive/naïve advanced prostate cancer and treatment of castration-resistant prostate cancer., Conclusion: This is the first regional consensus on prostate cancer management from the Middle East. The following recommendations will be useful to urologists and oncologists practicing in all areas with limited access to specialist multi-disciplinary teams, diagnostic modalities and treatment resources.

Background: Bladder leiomyomas are benign mesenchymal neoplasms and very rare urinary tumours that represent <0.5% of all bladder tumours, with only 250 cases reported worldwide to date. The importance of recognising their characteristic features, leading to their correct treatment, is fundamental. Therefore, we reviewed reports of leiomyomas of the urinary bladder, their causes, clinical presentations, imaging methods and surgical management, updated to 2012., Methods: We retrospectively reviewed articles published in the USA, Europe and Asia, from 1953 to date, using PubMed, Medscape, Medline and the several major journals. We report areas of controversies and well-established guidelines., Results: We reviewed 36 articles that confirmed, with a high level of evidence-based medicine, that the male to female ratio is equal, the cause of bladder leiomyomas remains unknown, and their most common presentation is obstructive uropathy; endovesical tumours are the most common. Their radiological diagnosis can be made by ultrasonography, computed tomography or magnetic resonance imaging. Complete surgical resection is a very effective treatment, associated with almost no recurrence., Conclusion: In symptomatic patients a complete surgical resection can give a very good outcome, with almost no recurrence.