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In our current era, a new rapidly spreading pandemic disease called coronavirus disease (COVID-19), caused by a virus identified as a novel coronavirus (SARS-CoV-2), is becoming a crucial threat for the whole world. Currently, the number of patients infected by the virus is expanding exponentially, but there is no commercially available COVID-19 medication for this pandemic. However, numerous antiviral drugs are utilized for the treatment of the COVID-19 disease. Identification of the appropriate antivirus medicine to treat the infection of COVID-19 is still a complicated and uncertain decision. This study's key objective is to develop a novel approach called q-rung orthopair probabilistic hesitant fuzzy rough set (q-ROPHFRS), which incorporates the q-rung orthopair fuzzy set, probabilistic hesitant fuzzy set, and rough set structures. New q-ROPHFR aggregation operators have been established: the q-ROPHFR Einstein weighted averaging (q-ROPHFREWA) operator and the q-ROPHFR Einstein weighted geometric (q-ROPHFREWG) operator. In this study, we explored some basic features of the developed operators. Afterward, to demonstrate the viability and feasibility of the established decision-making approach in real-world applications, a case study related to selecting drugs for COVID-19 pandemic is addressed. Furthermore, a comprehensive comparison with the q-rung orthopair probabilistic hesitant fuzzy rough TOPSIS technique is also presented to illustrate the benefits of the new framework. The obtained results confirm the reliability and effectiveness of the proposed approach for finding uncertainty in real-world decision-making. [ABSTRACT FROM AUTHOR]

Objective  The aim of this study is to present our experience in dealing with middle ear adenomas (MEAs), very rare tumors of the middle ear. Methods  The medical notes of individuals with MEAs treated in tertiary referral; academic settings were retrospectively reviewed. We recorded the presenting symptoms, imaging findings, and pathology results. We additionally examined our surgical outcomes, follow-up period, recurrence, and morbidity. Results  We identified four patients with MEAs: two males and two females with an average age of 36.25 years (range = 27–51 years). Despite the detailed imaging studies, including computed tomography and magnetic resonance imaging with intravenous contrast administration, a biopsy was essential in setting the diagnosis. Total surgical resection was achieved in all patients without any recurrence over an average of 6 years (range = 3–10 years). Complete ipsilateral deafness was the commonest surgical morbidity due to footplate infiltration by the tumor. Conclusion  Total surgical resection is the treatment of choice in MEAs to minimize the risk for recurrence; this can come with morbidity, mostly sensorineural deafness. Given the very limited literature, long-term follow-up is recommended. [ABSTRACT FROM AUTHOR]

Pulsed current–voltage characteristics have been measured for epitaxial SiC graphene under controlled lattice temperature conditions. The monolayer and AB stacked bilayer graphene is dry transferred on SiO2. The measured characteristics of two-terminal samples with coplanar electrodes demonstrate non-ohmic behaviour up to intermediate-high fields. At high currents thermal effects come into play and soft damage of the samples takes place. Bilayer graphene samples withstand 20 kV cm−1 electric field when few nanosecond voltages pulses are applied. The results are treated in terms of hole drift velocity estimated from the data on current under the assumption of uniform electric field and constant hole density. The highest velocity of ∼3.5–5 × 106 cm s−1 (∼1.5 × 107 cm s−1) is estimated for the bilayer (monolayer) graphene. The velocity results are interpreted with hot phonons. High frequency noise is measured at 10 GHz for the monolayer graphene and the associated shot noise is resolved. [ABSTRACT FROM AUTHOR]

The fast spread of coronavirus disease (COVID-19) caused by SARSCoV- 2 has become a pandemic and a serious threat to the world. As of May 30, 2020, this disease had infected more than 6 million people globally, with hundreds of thousands of deaths. Therefore, there is an urgent need to predict confirmed cases so as to analyze the impact of COVID-19 and practice readiness in healthcare systems. This study uses gradient boosting regression (GBR) to build a trained model to predict the daily total confirmed cases of COVID-19. The GBR method can minimize the loss function of the training process and create a single strong learner from weak learners. Experiments are conducted on a dataset of daily confirmed COVID-19 cases from January 22, 2020, to May 30, 2020. The results are evaluated on a set of evaluation performance measures using 10-fold cross-validation to demonstrate the effectiveness of the GBR method. The results reveal that the GBR model achieves 0.00686 root mean square error, the lowest among several comparative models. [ABSTRACT FROM AUTHOR]

The optical response of graphene-MoS2 heterojunctions is investigated. Spatial resolution photoresponse maps obtained using multiple bias conditions are measured and analyzed by exciting the graphene-MoS2 heterojunction area, MoS2, and Ti-MoS2 junction on the same device with an 800 nm wavelength Ti-Sapphire raster scanning laser. It is found that a large photothermal electric (PTE) effect is the dominant mechanism for photoresponse in a graphene-MoS2 heterojunction. Responsivities of 0.139 mA/W and 0.019 mA/W on the graphene-MoS2 heterojunction area and 0.457 mA/W and 0.032mA/W on the Ti-MoS2 junction area are observed with and without a bias, respectively, using a 430 lW laser. Current enhancement due to laser illumination is observed as far as 14 µm from the edge of the graphene-MoS2 heterojunction. Voltage generated by the PTE effect lowers the Schottky barrier junction, enabling more current flow during laser excitation. Photothermal-generated voltages of 0.22-0.47mV and 31.8-37.9mV are estimated at the graphene-MoS2 heterojunction and the Ti-MoS2 junction, respectively. [ABSTRACT FROM AUTHOR]

Background: screening for prostate cancer (PCa) is surrounded by controversies regarding the benefits, risks and uncertainties of undergoing the screening. Current practices of prostate cancer involve measuring the level of PSA and digital rectal examination. This study aimed to measure the knowledge and awareness of undergoing a prostate cancer screening and the available treatment options amongst the participants. Method: a questionnaire-based quantitative cross-sectional study which focuses on determining the knowledge of prostate cancer screening and management in a hospital in Riyadh. Results: three hundred and twenty-three participants filled the surveys (100% males), more than 80% of all ages had heard about prostate cancer and that it is a disease of the male. A higher level of education is significantly associated with the level of awareness (P-value <0.001). More educated participants selected 40 years old as the appropriate age for PCa screening (P-value 0.009) and radiotherapy as the mode of treatment (P-value 0.01). 43.34% saw PCa as a cause of death and 41.4% saw it associated with smoking. Only 17.84% undergo continuous PCa screening most of them in 50-60 age group with "reassurance" as the main motivator. 37.8% of the participants did not know the symptoms of PCa and around 25% selected pain in micturition, difficult frequent micturition and bone pain as symptoms of PCa. Conclusion: although prostate cancer is known amongst the majority of the participants, only a minority of them has knowledge of the symptoms and undergoes regular screening. [ABSTRACT FROM AUTHOR]

Correction for 'Controlled p-type substitutional doping in large-area monolayer WSe2 crystals grown by chemical vapor deposition' by Stephen A. Campbell et al., Nanoscale, 2018, 10, 21374-21385.

Tungsten diselenide (WSe 2 ) is a particularly interesting 2D material due to its p-type conductivity. Here we report a systematic single-step process to optimize crystal size by variation of multiple growth parameters resulting in hexagonal single crystals up to 165 μm wide. We then show that these large single crystals can be controllably in situ doped with the acceptor Niobium (Nb). First principles calculations suggest that substitutional Nb doping of W would yield p-doping with no gap trap states. When used as the active layer of a field effect transistor (FET), doped crystals exhibit conventional p-type behavior, rather than the ambipolar behaviour seen in undoped WSe 2 FETs. Nb-doped WSe 2 FETs yield a maximum field effect mobility of 116 cm 2 V -1 s -1 , slightly higher than its undoped counterpart, with an on/off ratio of 10 6 . Doping reduces the contact resistance of WSe 2 , reaching a minimum value of 0.55 kΩμm in WSe 2 FETs. The areal density of holes in Nb-doped WSe 2 is approximately double that of undoped WSe 2 , indicating that Nb doping is working as an effective acceptor. Doping concentration can be controlled over several orders of magnitudes, allowing it to be used to control: FET threshold voltage, FET off-state leakage, and contact resistance.

The electrical properties of multilayer MoS2/graphene heterojunction transistors are investigated. Temperature-dependent I-V measurements indicate the concentration of unintentional donors in exfoliated MoS2 to be 3.57 × 10(11) cm(-2), while the ionized donor concentration is determined as 3.61 × 10(10) cm(-2). The temperature-dependent measurements also reveal two dominant donor levels, one at 0.27 eV below the conduction band and another located at 0.05 eV below the conduction band. The I-V characteristics are asymmetric with drain bias voltage and dependent on the junction used for the source or drain contact. I-V characteristics of the device are consistent with a long channel one-dimensional field-effect transistor model with Schottky contact. Utilizing devices, which have both graphene/MoS2 and Ti/MoS2 contacts, the Schottky barrier heights of both interfaces are measured. The charge transport mechanism in both junctions was determined to be either thermionic-field emission or field emission depending on bias voltage and temperature. On the basis of a thermionic field emission model, the barrier height at the graphene/MoS2 interface was determined to be 0.23 eV, while the barrier height at the Ti/MoS2 interface was 0.40 eV. The value of Ti/MoS2 barrier is higher than previously reported values, which did not include the effects of thermionic field emission.