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Purpose To evaluate the indications, outcomes, and complications of the usage of Aurolab Aqueous Drainage Implant (AADI) using mitomycin-C. Methods A retrospective case series of patients who underwent AADI placement using mitomycin-C between April 2018 and June 2020 at Ain Shams University Hospitals, Cairo, Egypt. The data was extracted from the records of the patients with a minimum of 1 year of follow-up. Complete success was defined as IOP ≥ 5 mmHg and ≤ 21 mmHg or reduction of IOP by ≥ 20% from baseline without antiglaucoma medications (AGMs). Qualified success was defined as reaching the same IOP range with the aid of AGM. Results A total of 50 eyes of 48 patients were included. Neovascular glaucoma represented the commonest indication (13 patients, 26%). The mean preoperative IOP was 34.0 ± 7.1 mmHg, with a median number of AGM of 3 (mean ± SD = 2.84 ± 1), while the mean IOP after 12 months was 14.3 ± 4 with a median number of AGM of 0. (mean ± SD = 0.52 ± 0.89) (p Conclusion AADI with using mitomycin-C and ripcord during the surgery is an effective and relatively safe method of control of IOP in refractory and advanced cases of glaucoma, with an overall success rate of 94%.

Background Postoperative hemorrhage is a potential complication of tonsillectomy, and early diagnosis and adequate management are mandatory to prevent hemorrhagic shock. The aim of this study was to assess the safety and efficacy of transcatheter embolization of recurrent post-tonsillectomy hemorrhage by using N-butyl 2-cyanoacrylate. Results We performed a retrospective analysis of the medical records, imaging findings, technical details, and clinical outcome of eight patients with delayed post-tonsillectomy hemorrhage who underwent endovascular embolization. All patients were followed up; technical and clinical successes of treatment were evaluated. All patients had arterial pseudoaneurysm as a source of bleeding. The injured artery was facial artery in four patients, lingual artery in three patients, and linguofacial trunk in one patient. All lesions were treated by endovascular embolization using NBCA glue. All patients were successfully embolized with no clinical complications. In one patient with pseudoaneurysm at the ostium of the facial artery, after filling the pseudoaneurysm with glue, inadvertently proximal reflux into the adjacent part of the external carotid artery (ECA) occurred leading to its occlusion with no related immediate or delayed complication. Conclusion Endovascular embolization is an effective and almost safe procedure in the management of recurrent post-tonsillectomy bleeding. In such cases, we can use NBCA glue with certain precautions as an effective appropriate embolizing agent.

To report visual impairment and blindness among the patients attending a glaucoma clinic in a tertiary university hospital and highlight the possible risk factors that could be addressed later. A retrospective analysis of the medical records of the patients attending the glaucoma clinic in Ain Shams University Hospitals over a period of one year was conducted. Visual impairment classification was done according to the International Classification of Diseases and Related Health Problems (ICD-11) based on the best-corrected visual acuity in the better-seeing eye. Data including diagnosis, history of previous surgery, and duration of glaucoma were extracted and analyzed. The medical records of the first visit of 118 patients (58 males and 60 females) were included in this study. Secondary glaucoma was the most common type presented (38 patients, 32.2%), followed by primary open–angle glaucoma (35 patients, 29.6%). Sixty-seven patients (56.7%) were considered visually impaired, while seven patients (5.9%) were considered blind. Forty-one patients (34.7%) were considered mono-ocular blind. There is a high incidence of visual impairment and blindness among glaucoma patients presented to the glaucoma clinic in the tertiary hospital. A further nation-wide study and possibly, an early surveillance program for glaucoma are needed.

One of the most important challenges in fluid mechanics, gas dynamics, and hydraulic machinery fields is measuring the flow velocity with high accuracy. It is more important in large systems; such as thermal power stations, large scale power generations, and combined cycle power plants. The exact estimation of the measurement uncertainty inflow velocity is extremely important in evaluating the accuracy of the measurement. This work describes the problem of estimating measurement uncertainty when there are two or more dominant components of the uncertainty budget. . Two methods, analytical and numerical methods are used to study the comparative analysis for the results of determining the expanded uncertainty of measurement using two methods: analytical method and the numerical method. The analytical method uses the law of uncertainty propagation and is based on the estimation of uncertainty values of type A and B, while the numerical technique depends on the evaluation of measured samples by the Monte Carlo method using a random number generator. The aim of this article is to show the Monte Carlo method as an alternative way to determine the distribution of individual components of the measurement uncertainty budget. Also, the measurement of liquid flow velocity by an ultrasonic method has been analyzed, which is commonly used due to high measurement accuracy and non-invasiveness. Due to the complexity of the equation defining the measured flow velocity, determining the measurement uncertainty is not an easy task.

Background Pelvic congestion syndrome (PCS) is a problematic cause of chronic pelvic pain in women. It is thought to result from venous insufficiency of either ovarian or pelvic veins. Patients also present a variety of symptoms including dysuria and dyspareunia as well as vulva and buttock varicosities. The aim of this study is to evaluate the efficacy of multi-detector CT (MDCT) in diagnosis of PCS. Two hundred patients were included in our study and underwent CT venography of the abdomen and pelvis. Results We performed a prospective comparative study conducted on 200 patients. Thirty patients (15%) were diagnosed as PCS. There were congestion of the ovarian venous plexus and uterine venous engorgement in all patients. Filling of the veins across the midline was noted in 10 patients and filling of the vulval and thigh varicosities was noted in 3 patients. Ten patients had right ovarian vein dilatation; 12 patients had left ovarian vein dilatation; while 8 patients had bilateral ovarian vein dilatation. The right ovarian vein mean diameter (± SD) = 7.1 ± 0.8 mm; while the left ovarian vein mean diameter (± SD) = 7.6 ± 1 mm. Left ovarian venous reflux was found in 6 cases while no pathological reflux depicted on right side. Conclusions CT venography is considered as one of the initial investigations for the diagnosis of PCS in female patients with chronic pelvic pain making the further assessment by ovarian venography is for interventional management of diagnosed cases.

Natural wood has been used in structural applications for decades. Smoke from wood fires, additives and wood-protective coatings is a cause of death and serious injury in limited ventilation compartment. Ventilation restrictions in modern day designs complicate the combustion process and increase incomplete combustion products due to a reduction in the amount of oxygen available for fuel oxidation. Jordanian hardwood samples have been examined, tested and evaluated according to their mass loss rates, specific optical density, mass optical density, transmittance, and visibility using qualitative research used to realise the dynamics of fire phenomena. Four types of natural wood were tested under different heat fluxes with different Flaming combustion in a Smoke Density Chamber (SDC). The samples studied were Beech, Oak, Rhamnus, and Abies. The samples have been exposed to 25 and 50 kW/m2 heat fluxes in a limited ventilation compartment. Twelve samples were tested, each with dimensions of 75 x 75 mm and 10 mm thickness. An evaluation of the tested parameters, such as mass loss rate (MLR), specific optical density, transmittance, visibility and mass optical density (MOD have been carried out to determine their effectiveness as predictive parameters. Main results shows Beech has the lower values of specific optical density despite it has higher values of MLR% and MOD compared to other samples studied. Also, the mass loss rate (MLR %) increases with the heat flux even with different flaming conditions. In the opposite, there is a strong dependence for the mass optical density (MOD) on the heat flux and flaming conditions. Key conclusions have been drawn up that could be used in wood products and future works. The main objective of this work is to model the fire dynamic behavior in the pre-fire time. The results of this study can provide the bases for ventilation process and considerations of using natural woods in Jordan for different applications.

We investigate the impact of localized laser heating on the auto-oscillation properties of a 170 nm wide nano-constriction spin Hall nano-oscillators (SHNOs) fabricated from a NiFe/Pt bilayer on a sapphire substrate. A 532 nm continuous wave laser is focused down to a spot size of about 500 nm at a power ranging from 0 to 12 mW. Through a comparison with resistive heating, we estimate a local temperature rise of about 8 K/mW. We demonstrate reversible laser tuning of the threshold current, the frequency, and the peak power and find that the SHNO frequency can be tuned by up to 350 MHz, which is over three times more than the current tuning alone. Increasing the temperature also results in increased signal jitter, an increased threshold current, and a reduced maximum current for auto-oscillations. Our results open up for optical control of single SHNOs in larger SHNO networks without the need for additional voltage gates.

Using micromagnetic simulations, we study the interplay between strongly voltage-controlled magnetic anisotropy (VCMA), [Formula: see text]200 kJ/m3, and gate width, [Formula: see text] 10–400 nm, in voltage-gated W/CoFeB/MgO based nano-constriction spin Hall nano-oscillators. The VCMA modifies the local magnetic properties such that the magnetodynamics transitions between regimes of (i) confinement, (ii) tuning, and (iii) separation with qualitatively different behaviors. We find that the strongest tuning is achieved for gate widths of the same size as the constriction width, for which the effective damping can be increased an order of magnitude compared to its intrinsic value. As a consequence, voltage control remains efficient over a very large frequency range, and subsequent manufacturing advances could allow spin Hall nano-oscillators to be easily integrated into next-generation electronics for further fundamental studies and industrial applications.

Purpose To compare the measured or calculated angle Kappa using Oculus pentacam HR, Sirius and Orbscan III devices. Patients and methods A prospective randomized cohort study, conducted on 47 eyes of 47 healthy orthotropic individuals, with an age range of 18–50 years and a corrected Snellen’s distance visual acuity (CDVA) of 0.8 decimal or better. Angle Kappa is assessed directly using Orbscan® III software version 1.8.165.1. (Bausch and Lomb Rochester, New York, United States), while Pentacam® HR 1.21r.65 (Oculus Optikgeräte GmbH, Wetzlar, Germany) and Sirius device (CSO, version 3.2.1.60, Costruzione Strumenti Oftalmici, Florence, Italy) were used to calculate angle kappa indirectly. Results Least mean difference of estimated angle Kappa was between Orbscan and Pentacam devices (− 0.18° ± 1.8), and it was statistically insignificant (p value = 0.1294). Differences between both Orbscan and Sirius, and Pentacam and Sirius were statistically significant (p value = 0.0004 and Conclusion Pentacam parameters can be used as a reliable method to calculate angle kappa indirectly, without usage of any additional measurements from other machine. Sirius device parameters could also be used, but with less accurate results. A simple modification to those devices’ software to calculate it, and incorporate it in the printout is possible, and highly recommended.

In spin Hall nano-oscillators (SHNOs), pure spin currents drive local regions of magnetic films and nanostructures into auto-oscillating precession. If such regions are placed in close proximity to each other they can interact and may mutually synchronize. Here, we demonstrate robust mutual synchronization of two-dimensional SHNO arrays ranging from 2 × 2 to 8 × 8 nano-constrictions, observed both electrically and using micro-Brillouin light scattering microscopy. On short time scales, where the auto-oscillation linewidth $$\Delta f$$ is governed by white noise, the signal quality factor, $$Q=f/\Delta f$$, increases linearly with the number of mutually synchronized nano-constrictions (N), reaching 170,000 in the largest arrays. We also show that SHNO arrays exposed to two independently tuned microwave frequencies exhibit the same synchronization maps as can be used for neuromorphic vowel recognition. Our demonstrations may hence enable the use of SHNO arrays in two-dimensional oscillator networks for high-quality microwave signal generation and ultra-fast neuromorphic computing. Synchronization of oscillators can be used to carry out cognitive tasks. Large two-dimensional arrays of synchronized spin Hall nano-oscillators have now been demonstrated, and may in future enable neuromorphic computing on the nanoscale.

Spin torque and spin Hall effect nano-oscillators generate high intensity spin wave auto-oscillations on the nanoscale enabling novel microwave applications in spintronics, magnonics, and neuromorphic computing. For their operation, these devices require externally generated spin currents either from an additional ferromagnetic layer or a material with a high spin Hall angle. Here we demonstrate highly coherent field and current tunable microwave signals from nano-constrictions in single 15–20 nm thick permalloy layers with oxide interfaces. Using a combination of spin torque ferromagnetic resonance measurements, scanning micro-Brillouin light scattering microscopy, and micromagnetic simulations, we identify the auto-oscillations as emanating from a localized edge mode of the nano-constriction driven by spin-orbit torques. Our results pave the way for greatly simplified designs of auto-oscillating nano-magnetic systems only requiring single ferromagnetic layers with oxide interfaces., Spin torque nano-oscillatiors promise novel microwave applications but the functioning relies on the spin current from additional ferromagnetic or metal layers. The authors here achieved in a single ferromagnetic layer sandwiched by nonmagnetic insulators the spin wave auto-oscillations due to a localized edge mode of the nano-constriction.

Controlling the directionality of spin waves is a key ingredient in wave-based computing methods such as magnonics. In this paper, we demonstrate this particular aspect by using an all-optical point-like source of continuous spin waves based on frequency comb rapid demagnetization. The emitted spin waves contain a range of k-vectors and by detuning the applied magnetic field slightly off the ferromagnetic resonance (FMR), we observe X-shaped caustic spin-wave patterns at $70^{\circ}$ propagation angles as predicted by theory. When the harmonic of the light source approaches theFMR, the caustic pattern gives way to uniaxial spin-wave propagation perpendicular to the in-plane component of the applied field. This field-controlled propagation pattern and directionality of optically emitted short-wavelength spin waves provide additional degrees of freedom when designing magnonic devices., 5 pages, 4 figures

Ferromagnetic materials dominate as the magnetically active element in spintronic devices, but come with drawbacks such as large stray fields, and low operational frequencies. Compensated ferrimagnets provide an alternative as they combine the ultrafast magnetization dynamics of antiferromagnets with a ferromagnet-like spin-orbit-torque (SOT) behavior. However to use ferrimagnets in spintronic devices their advantageous properties must be retained also in ultrathin films (t < 10 nm). In this study, ferrimagnetic Gdx(Fe87.5Co12.5)1-x thin films in the thickness range t = 2-20 nm were grown on high resistance Si(100) substrates and studied using broadband ferromagnetic resonance measurements at room temperature. By tuning their stoichiometry, a nearly compensated behavior is observed in 2 nm Gdx(Fe87.5Co12.5)1-x ultrathin films for the first time, with an effective magnetization of Meff = 0.02 T and a low effective Gilbert damping constant of {\alpha} = 0.0078, comparable to the lowest values reported so far in 30 nm films. These results show great promise for the development of ultrafast and energy efficient ferrimagnetic spintronic devices., Comment: 7 Pages, 4 Figures

Reliable in situ control of spin wave (SW) excitation between localized and propagating SW modes is of great interest for both fundamental and applied spintronics and magnonics. While spin-transfer-torque-generated SWs can typically be tuned directly via the driving current, the frequency of the highest intensity SWs, achieved in the strongly self-localized magnetic droplet soliton, is virtually current independent, as the droplet frequency is given by the intrinsic material properties. Here, we demonstrate, using micromagnetic simulations, how the droplet frequency can be efficiently tuned by an applied voltage through the effect of electric field (E-field)-dependent perpendicular magnetic anisotropy (PMA). It is found that as the PMA decreases, the droplet begins to distort and eventually collapses to give way to propagating SWs. However, due to the geometrically confined structures, the radially propagating SWs are reflected by the periphery boundary of the sample, and then the forward and backward SWs superpose to produce a series of standing SWs. The node number of the standing SWs strongly depends on the sample size as well as the applied E field. These findings provide a deeper understanding of magnetic excitation properties, which will be helpful for designing advanced spintronic devices.

To report visual impairment and blindness among the patients attending a glaucoma clinic in a tertiary university hospital and highlight the possible risk factors that could be addressed later.A retrospective analysis of the medical records of the patients attending the glaucoma clinic in Ain Shams University Hospitals over a period of one year was conducted. Visual impairment classification was done according to the International Classification of Diseases and Related Health Problems (ICD-11) based on the best-corrected visual acuity in the better-seeing eye. Data including diagnosis, history of previous surgery, and duration of glaucoma were extracted and analyzed.The medical records of the first visit of 118 patients (58 males and 60 females) were included in this study. Secondary glaucoma was the most common type presented (38 patients, 32.2%), followed by primary open-angle glaucoma (35 patients, 29.6%). Sixty-seven patients (56.7%) were considered visually impaired, while seven patients (5.9%) were considered blind. Forty-one patients (34.7%) were considered mono-ocular blind.There is a high incidence of visual impairment and blindness among glaucoma patients presented to the glaucoma clinic in the tertiary hospital. A further nation-wide study and possibly, an early surveillance program for glaucoma are needed.

Purpose To compare single-step transepithelial photorefractive keratectomy (TPRK) to conventional alcohol assisted epithelial removal then photorefractive keratectomy (AAPRK) regarding pain, epithelial healing, visual acuity, corneal haze measured subjectively and objectively, higher order aberrations changes, contrast sensitivity and vector analysis of astigmatic correction with one year follow-up. Methods A prospective double-blind randomized study of 29 subjects (58 eyes) who underwent myopic aberration-free laser correction by smart pulse technology using Schwind Amaris 1050 Hz with 1-year follow-up. Right eye was randomly treated by AAPRK or TPRK. Postoperative assessment was performed on day 1 and 3, at 1st week, and 1st, 3rd, 6th, and 12th months. Patients were assessed for pain, epithelial healing, visual acuity, corneal haze, astigmatic correction, higher order aberrations and contrast sensitivity. Results Epithelial healing was complete by the 3rd day in 62.1% of AAPRK eyes and in 89.7% of TPRK eyes. First day postoperative pain was higher in TPRK group (p = 0.0134). The decimal uncorrected visual acuity at 12 months was 1.47 ± 0.39 and 1.57 ± 0.38 in the AAPRK and TPRK groups respectively (p = 0.3719). Post-photorefractive keratectomy haze reached a final level of 0.04 ± 0.14 and 0.02 ± 0.1 in AAPRK and TPRK groups respectively (p = 0.5607). Contrast sensitivity was comparable in low and high frequency cycles per degree. Vector analysis of astigmatic correction showed correction index at one year of 0.99 and 1.05 for AAPRK and TPRK groups respectively. Conclusions Alcohol assisted and transepithelial photorefractive keratectomy have comparable results regarding safety and efficacy.

Purpose The purpose of this study was to evaluate the peripapillary choroidal thickness (PPCT) and its correlation with nerve fiber layer thickness (NFLT) in eyes with primary open-angle glaucoma (POAG). Patients and methods Eighty eyes were included in this study. They were divided into two groups: group I (38 eyes) of normal individuals and group II (42 eyes) with POAG. All eyes underwent complete ophthalmic examination with visual field testing using Humphery visual field analyzer. NFLT was measured in all eyes using Heidelberg Spectralis-optical coherence tomography with a circle of 3.4-mm diameter around the optic disc. PPCT was measured using enhanced deep imaging (EDI) technique of Heidelberg Spectralis-optical coherence tomography. Results The mean age was 51.74±4.27 years in group I and 53.7±3.7 years in group II. Global NFLT in group I was 103.6±6.3 μm and in group II it was 76.9±8.5 μm with a significant difference between the two groups (P

This work presents an energy/exergy analysis to investige performance of thermal storage unit which loaded with a commercial phase change material (Plus ICE H190). The influence of fluid parameters on the energy/exergy effectiveness was examined. The temporal changes of the energy and exergy rate and performace of the storage unit are obtained in the results. Latent heat principle is considered an efficient method to gain a higher effectiveness of system from an energy and exergy aspects. The fluid mass flow rate during charging and discharging periods were 2.50 kg/min and 1.26 kg/min, respectively. The results showed a significant increase of thermal resistance on the thermal storage unit performance. Fluid and phase change material show significant temperature difference on the rate of energy/exergy quantites and the time of melting or soldification. Ther results indicated that the average rate of energy and exergy were 1.3 kW and 0.54 kW, respectively. Wheras, energy and exergy average rate during discarging periods were 1.1 kW and 0.31 kW, respectively. Also, the global rate during the experimetal periods were about 84% and 54%, respectively. Article History : Received July 6 th 2017; Received in revised form September 15 th 2017; Accepted 25 th Sept 2017; Available online How to Cite This Article : Olimat, A.N., Awad, A.S., Al-Gathain, F.M., and Shaban, N.A.. (2017) Performance of Loaded Thermal Storage Unit With A Commercial Phase Change Materials Based on Energy and Exergy Analysis. International Journal of Renewable Energy Develeopment, 6(3),283-290. https://doi.org/10.14710/ijred.6.3.283-290

An important property of spin-torque nano-oscillators (STNOs) is their ability to produce a frequency modulated (FM) signal, which is very critical for communication applications. We here demonstrate a novel single sideband (SSB) modulation phenomenon using a magnetic tunnel junction (MTJ)-based STNO, which saves transmission bandwidth and in principle should minimize attenuation for wireless communication. Experimentally, lower single sidebands (LSSBs) have been successfully demonstrated over a wide range of modulation frequency, f m = 150 MHz-1 GHz. The observed LSSBs are determined by the intrinsic properties of the device, which can be modeled well by a nonlinear frequency and amplitude modulation formulation and reproduced in macrospin simulations. Moreover, our macrospin simulation results show that the range of modulation current and modulation frequency for generating SSBs can be controlled by the field-like torque and biasing conditions.

A micromechanical model is applied to examine the tensile properties of composite materials filled with multi-wall CNT oriented in in-plane and out-of-plane direction and a quantitative micromechanical model for the mechanical behavior of CNT-composites has been developed. Digimat-MF is used to generate a realistic three-dimensional microstructure for the current carbon nanotube/ epoxy composite. The Digimat model simulates a system of aligned carbon nanotubes arranged in-plane and another one having out of plane arrangement of reinforcements. A second model shows a representative volume element for the current nano-composite, in which the carbon nanotubes were simulated as a randomly (fully) dispersed, where all particles have been separated from each other. The predicted mechanical properties are compared with experimental tensile properties of composite materials reinforced with multi-wall CNTs arranged in in-plane and out-of-plane direction. A good agreement between the micromechanical modeling and the experimental part is observed. Results show that the elastic energy stored in -the-through thickness direction reinforced composites is about two times higher than that in the pure polymer.

Propagating spin waves generated by a metal-based spin Hall nano-oscillator for highly energy-efficient spin wave technology., Spin-orbit torque (SOT) can drive sustained spin wave (SW) auto-oscillations in a class of emerging microwave devices known as spin Hall nano-oscillators (SHNOs), which have highly nonlinear properties governing robust mutual synchronization at frequencies directly amenable to high-speed neuromorphic computing. However, all demonstrations have relied on localized SW modes interacting through dipolar coupling and/or direct exchange. As nanomagnonics requires propagating SWs for data transfer and additional computational functionality can be achieved using SW interference, SOT-driven propagating SWs would be highly advantageous. Here, we demonstrate how perpendicular magnetic anisotropy can raise the frequency of SOT-driven auto-oscillations in magnetic nanoconstrictions well above the SW gap, resulting in the efficient generation of field and current tunable propagating SWs. Our demonstration greatly extends the functionality and design freedom of SHNOs, enabling long-range SOT-driven SW propagation for nanomagnonics, SW logic, and neuromorphic computing, directly compatible with CMOS technology.

A single nanoconstriction spin-Hall nano-oscillator (NC-SHNO) in out-of-plane fields is presented as a nonlinear amplitude and frequency modulator operated by radio-frequency (RF) current modulation. The current modulation was carried out in different NC-SHNO nonlinearity regimes corresponding to negative, zero, and positive values of $df/dI$ in order to investigate the device response to an 80 MHz modulating current. Our study shows that current modulation of SHNOs can be quantitatively predicted by a nonlinear frequency and amplitude modulation (NFAM) model using the values of $df/dI$ and $d^2f/dI^2$ extracted from the free-running frequency $f$ versus current $I$ profile. The NFAM model reproduces the asymmetric sideband amplitude as well as the red and blue shift of the frequency in excellent agreement with the experimental results. The ability to predict the modulation process is a necessary benchmark in designing SHNO modulators for future integrated microwave circuits.