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This paper presents a 3 dB compact Ultra-Wide-Band (UWB) Substrate Integrated Gap Waveguide (SIGW) based hybrid coupler suitable for 5G mm-wave applications. It is a key component in signal processing for wireless communication. It provides a way to control the power distribution of the signal along different ports. It could be used to achieve beamforming and adaptive antenna system. The design steps started with implementing a unit cell of the gap waveguide structure satisfying the required bandwidth of the coupler. A supercell is then implemented. A network of complete ridges is constructed. A further step is to design a coupling section which achieves the required power distribution along the coupling and isolated ports. This coupling section is implemented using a novel approach of inserting an elliptical slot with variable major and minor axes with a certain orientation that achieves the standard performance of a 3 dB directional coupler with 90◦±5% phase shift. For precise adjustment of this amplitude and phase, vias are further added perpendicular to the major axis of the slot. Its dimension and location have to be optimized. The Finite-Integral-Time-Domain (FDTD) analysis method is adopted (CST Microwave Studio). In addition, another novel approach is developed on this coupler such that the transition and gap layer is implemented on the same PCB layer, which saves the number of layers to only two layers compared to the usual three layers used in literature. Also, using SIGW technology saves the collapse of the top ground layer on the ridge structure, and only plastic pins are used to fix the two layers. The proposed coupler is fabricated and tested, and the results show that it serves the majority of frequency bands employed in 5G systems in the USA and Canada. [ABSTRACT FROM AUTHOR]

Archaeological monuments of Saqqara region are affected by cracking, weathering and man-made actions that have resulted in different types of deterioration in the long run. Accordingly historical masonry tombs in Saqqara require a full characterization of the materials used for their construction, before any restoration processes. The assessment of the mechanical and physical characteristics of the building materials is based on visual observation, sampling of the building materials used and laboratory testing of the samples (bulk density, porosity, water absorption, optical microscope, polarizing microscope (PM), XRD, SEM, compressive strength, ...etc.). The present study is concerned with the restoration and reconstruction of a masonry tomb in Saqqara (Tomb of Queen Khenut), which over the years suffered significant damage due to various deterioration actions. Limestone used in the construction of historical buildings in Saqqara is classified as carbonates and salts with carbonate fragments stone. The stone is composed of carbonate cuttings; each of them is broclastic limemud stone to weak stone. This structure generally presents heterogeneous granular texture; with a very rare matrix and low cementation level between the internal components, causing a fair development of intergranular porosity. The values of bulk density are ranging from 2.22 to 2.33 gm/cm3. Otherwise, the results of porosity reveal remarkable differences between the different samples. Also the stone has low compressive strength values (The uniaxial compressive strength values varied from 96 to 104 Kg/cm2), due to the defects in its internal structure and decaying products. Finally, a damage description was carried out to identify the decaying forms. It is the basis for the quantitative rating of limestone damage by means of damage forms and products. Limestone in Queen Khenut's Tomb exhibits the need for restoration and preservation procedures. [ABSTRACT FROM AUTHOR]

The Mamluks cemetery, City of the dead, is one of the famous historical Islamic places that contain many outstanding structures. Limestone, which is the main building material used in the Mamluks cemetery buildings, always underwent weathering processes and deterioration factors. The present study is an analytical and petrographic assessment of limestone used in historical buildings in Cairo-Egypt. It is organized into three main sections. The first section provides a historical background of Mamluks cemetery. The second one sets out to evaluate the current situation of the decaying limestone. The third section explains the alteration mechanisms between deterioration forms and surrounding environmental factors. Visual, microscopic, and laboratory analysis by means of PM, XRD, and EDX highlighted the causes of limestone decaying. The decay phenomena of limestone in the (City of the dead) are independent of the exposure of the architectural surface and are strongly influenced by the sedimentary nature (micro laminations), which acts with the formation and distribution of salts as preferential planes for the formation of aggressive weathering forms. Another issue is related to the formation of cavities. Furthermore, small quartz grains occasionally occupy some shell cavities (chambers). [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to investigate the effect of instrument-assisted soft tissue mobilization (IASTM) versus myofascial release therapy (MRT) on college students with chronic mechanical neck pain (CMNP)., Methods: Thirty-three college students with a mean age of 21.33 ± 0.98 involved in distance learning due to the Corona Virus 2019 (COVID-19) restriction were randomized to receive either IASTM on the upper trapezius and levator scapulae muscles or MRT. Researchers measured their pain with a visual analog scale (VAS), function with neck disability index (NDI), and pain pressure threshold (PPT) with a pressure algometer. The subjects received eight therapy sessions over four weeks and outcome measures were assessed pre and post-intervention. The study was registered as a clinical trial on clinicaltrials.gov (registration number: NCT05213871)., Result: Unpaired t-test showed no statistical significance between the two groups post-intervention regarding improvement in pain, function, and PPT (p > 0.05)., Conclusion: This study showed insignificant differences between groups. However, we did not use a control group, indicating that the improvement in outcomes may not have been caused by the intervention., Study Design: Quasi-experimental two groups pre-posttest clinical trial., Level of Evidence: Therapy, level 2b., (© 2023. The Author(s).)

Background and Aim: The use of endoluminal flow diversion in bifurcation aneurysms has been questioned due to the potential for complications and lower occlusion rates. In this study we assessed outcomes of endovascular treatment of intracranial sidewall and bifurcation aneurysms with flow diverters., Methods: In July 2020, a literature search for all studies utilizing endoluminal flow diverter treatment for sidewall or bifurcation aneurysms was performed. Data were collected from studies that met our inclusion/exclusion criteria by two independent reviewers and confirmed by a third reviewer. Using random-effects meta-analysis the target outcomes including overall complications (hematoma, ischemic events, minor ischemic stroke, aneurysm rupture, side vessel occlusion, stenosis, thrombosis, transient ischemic stroke, and other complications), perioperative complications, and follow-up (long-term) aneurysm occlusion were intestigated., Results: Overall, we included 35 studies with 1084 patients with 1208 aneurysms. Of these aneurysms, 654 (54.14%) and 554 (45.86%) were classified as sidewall and bifurcation aneurysm, respectively, based on aneurysm location. Sidewall aneurysms had a similar total complication rate (R) of 27.12% (95% CI, 16.56%-41.09%), compared with bifurcation aneurysms (R, 20.40%, 95% CI, 13.24%-30.08%) (p = 0.3527). Follow-up angiographic outcome showed comparable complete occlusion rates for sidewall aneurysms (R 69.49%; 95%CI, 62.41%-75.75%) and bifurcation aneurysms (R 73.99%; 95% CI, 65.05%-81.31%; p = 0.4328)., Conclusions: This meta-analysis of sidewall and bifurcation aneurysms treated with endoluminal flow diverters demonstrated no significant differences in complications or occlusion rates. These data provide new information that can be used as a benchmark for comparison with emerging devices for the treatment of bifurcation aneurysms.

Objective: Recent studies suggest that the clinical course and outcomes of patients with coronavirus disease 2019 (COVID-19) and myasthenia gravis (MG) are highly variable. We performed a systematic review of the relevant literature with a key aim to assess the outcomes of invasive ventilation, mortality, and hospital length of stay (HLoS) for patients presenting with MG and COVID-19., Methods: We searched the PubMed, Scopus, Web of Science, and MedRxiv databases for original articles that reported patients with MG and COVID-19. We included all clinical studies that reported MG in patients with confirmed COVID-19 cases via RT-PCR tests. We collected data on patient background characteristics, symptoms, time between MG and COVID-19 diagnosis, MG and COVID-19 treatments, HLoS, and mortality at last available follow-up. We reported summary statistics as counts and percentages or mean±SD. When necessary, inverse variance weighting was used to aggregate patient-level data and summary statistics., Results: Nineteen studies with 152 patients (mean age 54.4 ± 12.7 years; 79/152 [52.0%] female) were included. Hypertension (62/141, 44.0%) and diabetes (30/141, 21.3%) were the most common comorbidities. The mean time between the diagnosis of MG and COVID-19 was7.0 ± 6.3 years. Diagnosis of COVID-19 was confirmed in all patients via RT-PCR tests. Fever (40/59, 67.8%) and ptosis (9/55, 16.4%) were the most frequent COVID-19 and MG symptoms, respectively. Azithromycin and ceftriaxone were the most common COVID-19 treatments, while prednisone and intravenous immunoglobulin were the most common MG treatments. Invasive ventilation treatment was required for 25/59 (42.4%) of patients. The mean HLoS was 18.2 ± 9.9 days. The mortality rate was 18/152 (11.8%)., Conclusion: This report provides an overview of the characteristics, treatment, and outcomes of MG in COVID-19 patients. Although COVID-19 may exaggerate the neurological symptoms and worsens the outcome in MG patients, we did not find enough evidence to support this notion. Further studies with larger numbers of patients with MG and COVID-19 are needed to better assess the clinical outcomes in these patients., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Introduction: Acute respiratory distress syndrome (ARDS) due to coronavirus disease 2019 (COVID-19) often leads to mortality. Outcomes of patients with COVID-19-related ARDS compared to ARDS unrelated to COVID-19 is not well characterized., Areas Covered: We performed a systematic review of PubMed, Scopus, and MedRxiv 11/1/2019 to 3/1/2021, including studies comparing outcomes in COVID-19-related ARDS (COVID-19 group) and ARDS unrelated to COVID-19 (ARDS group). Outcomes investigated were duration of mechanical ventilation-free days, intensive care unit (ICU) length-of-stay (LOS), hospital LOS, and mortality. Random effects models were fit for each outcome measure. Effect sizes were reported as pooled median differences of medians (MDMs), mean differences (MDs), or odds ratios (ORs)., Expert Opinion: Ten studies with 2,281 patients met inclusion criteria (COVID-19: 861 [37.7%], ARDS: 1420 [62.3%]). There were no significant differences between the COVID-19 and ARDS groups for median number of mechanical ventilator-free days (MDM: -7.0 [95% CI: -14.8; 0.7], p = 0.075), ICU LOS (MD: 3.1 [95% CI: -5.9; 12.1], p = 0.501), hospital LOS (MD: 2.5 [95% CI: -5.6; 10.7], p = 0.542), or all-cause mortality (OR: 1.25 [95% CI: 0.78; 1.99], p = 0.361). Compared to the general ARDS population, results did not suggest worse outcomes in COVID-19-related ARDS.

Context: In comparison with the published research on the surgical management of ulnar wrist pain, fewer studies that discuss the nonsurgical management of ulnar wrist pain exist., Objective: The purpose of this pilot study was to investigate the effect of ulnar-based wrist orthotics and strengthening exercises on subjects with ulnar wrist pain., Study Design: Prospective randomized controlled pilot study., Setting: Research laboratory., Participants: Thirty subjects with acute and subacute ulnar wrist pain and age ranging from 18 to 53., Interventions: Participants were randomized to receive either ulnar-based orthotics, ulnar-based orthotics plus strengthening exercises, or placebo intervention., Main Outcome Measures: The authors measured pain and function using the Patient-Rated Wrist Evaluation questionnaire, and grip strength using the JAMAR dynamometer, at baseline and at 2- and 4-week postrandomization. A mixed analysis of variance modeling was used to investigate the effect of the intervention over time., Results: There were statistically significant differences between the 2 intervention groups and the control group regarding improvement in pain, function, and strength, whereas there were no statistically significant differences between the 2 intervention groups over the 3 measurement occasions regarding the outcome measures., Conclusion: Based on the results, orthotics intervention is as effective as orthotics plus strengthening exercises in improving pain, function, and grip strength in subjects with ulnar wrist pain., Level of Evidence: Therapy, level 2b individual Randomized Controlled Trial.

Objective: The purpose of this study was to apply the Brief International Classification of Functioning (ICF) Core Set for Hand Conditions to the physical therapy outcome measures, and to evaluate the contribution of these measures to overall health in subjects with ulnar wrist pain., Methods: Thirty-five subjects with ulnar wrist pain received a 4-week home-based treatment program including orthotics and strengthening exercises. Investigators measured pain, function, grip strength, and overall health four weeks post-intervention. Regression analysis was used to investigate the effect of these variables on overall health represented by the Short Form (SF-36) questionnaire., Results: Fifty-three percent of the variability in SF-36 physical health summary scores was explained by the studied variables with grip strength predicting 31% of the variability., Conclusions: The Brief ICF Core Set for Hand Conditions can be a useful abridged list of categories relevant to functioning and health in subjects with ulnar wrist pain.

Background: Despite increased neuronal death, senile plaques, and neurofibrillary tangles observed in patients suffering from Alzheimer's disease (AD), the detailed mechanism of cell death in AD is still poorly understood., Method: We hypothesized that p38 kinase activates and then phosphorylates Bax, leading to its translocation to mitochondria in AD brains compared to controls. The aim of this study was to investigate the role of p38 kinase in phosphorylation and sub-cellular localization of pro-apoptotic Bax in the frontal cortex of the brains from AD and control subjects. Increased oxidative stress in AD individuals compared to control was evaluated by measuring the levels of carbonylated proteins and oxidized peroxiredoxin, an antioxidant enzyme. The relative amounts of p38 kinase and phospho-Bax in mitochondria in AD brains and controls were determined by immunoblot analysis using the respective antibody against each protein following immunoprecipitation., Results: Our results showed that the levels of oxidized peroxiredoxin-SO 3 and carbonylated proteins are significantly elevated in AD brains compared to controls, demonstrating the increased oxidative stress., Conclusion: The amount of phospho-p38 kinase is increased in AD brains and the activated p38 kinase appears to phosphorylate Thr residue(s) of Bax, which leads to its mitochondrial translocation, contributing to apoptosis and ultimately, neurodegeneration.

Toxicogenomics was used to examine mRNA expression profiles obtained from primary rat hepatocytes treated for 24h with 0.01 or 1.0 nM 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), 0.02 or 2.0 nM 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-PeCDF) and 0.1 or 10nM 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF). The concentrations of 2,3,4,7,8-PeCDF and 2,3,7,8-TCDF were chosen to be equivalent to 2,3,7,8-TCDD's concentration based on the toxic equivalency factor/toxic equivalent (TEF/TEQ) method for estimating biological potency. 2,3,7,8-TCDD at 1.0 nM altered the expression of 533 genes; 2,3,4,7,8-PeCDF at 2.0 nM altered 182 genes, and 2,3,7,8-TCDF at 10nM altered 154 genes. Of these, 57 genes were affected by all three congeners. Agglomerative hierarchical clustering revealed distinct congener-dependent gene subclusters. Principal components analyses of the microarray data revealed that these congeners cluster independently of one another. Data presented here demonstrate that equivalent TEQ concentrations of 2,3,7,8-TCDD, 2,3,4,7,8-PeCDF and 2,3,7,8-TCDF, while altering the expression of a small battery of genes in common, also produce substantial congener specific alterations in gene expression., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Ten partially sighted and 19 normally sighted eyes underwent excimer laser photorefractive keratectomy for the correction of myopia. Nine of the partially sighted and 17 of the normally sighted eyes had 12 months of follow-up. Epithelial healing was complete in all eyes by day 6. None of the eyes had recurrent erosions, infections, or other medical complications. An increase in corneal haze after surgery was followed by a slow trend toward clearing. Average uncorrected visual acuity in the 7 normally sighted eyes with attempted corrections of 5 diopters (D) or less was 20/40 from month 2 on; the eyes with greater than 5 D attempted corrections had an average of 20/80--at month 2, which declined to 20/200--by month 6. Best spectacle-corrected visual acuity was within +/- 1 Snellen line of preoperative values in 14 of the normally sighted eyes, improved 2 or more lines in 2 eyes, and worsened two or more lines in two eyes. Hard contact lens overcorrection restored all of the two-line loss in 1 eye and 1 line of the 3-line loss in the other. Refraction and keratometry indicated corneal flattening without induced astigmatism.

The appearance of haze in the central cornea following photoablation with a 193 nm excimer laser is an important factor in the postoperative course of this procedure. Data from 37 human eyes treated with photorefractive keratectomy, 4 eyes treated with phototherapeutic keratectomy, and 5 untreated eyes were used to evaluate the ability of a commercially available opacity lensometer to provide an objective measure of corneal clarity. We found that the opacity lensometer was able to detect light scattered from the cornea but was not sufficiently sensitive to distinguish reliably among excimer-treated eyes with degrees of corneal haze evaluated as clear, trace, or 1+ by slit-lamp microscope examination. In untreated, clear corneas, the values obtained with the opacity lensometer in eyes measured with and without a clear contact lens were within one unit of each other for any given eye, but values from eye to eye varied over a range of six units. In a test simulating different amounts of corneal haze using contact lenses evenly coated with nail polish enamel, the log-transformed opacity lensometer values varied directly with percent light scattering as determined by spectrophotometry. These results suggest that the opacity lensometer measurements are reliable and reproducible, but that in the human cornea something is being measured by the opacity lensometer that is not taken into account in clinical slit-lamp microscope evaluation. Overall, it appears that, in its present form, this instrument is not useful to measure corneal clarity after excimer laser photoablation.