Recent Advancements in GaN LED Technology

Gallium nitride (GaN)-based solid state lighting technology has revolutionized the semiconductor industry. The GaN technology has played a crucial role in reducing world energy demand as well as reducing the carbon footprint. As per the reports, the global demand for lighting has reduced around 13% of total energy consumption in 2018. The Department of Energy (USA) has estimated that bright white LED source could reduce their energy consumption for lighting by 29% by 2025. Most of the GaN LEDs are grown in c-direction, and this direction gives high growth rate and good crystal integrity. On the other hand, the c-plane growth induces piezoelectric polarization, which reduces the overall efficiency of LEDs since the last decade researchers round the globe working on III-N material to improve the existing technology and to push the limit of III-V domain. Now, the non-polar and semi-polar grown LEDs are under investigation for improved efficiency. With the recent development, the GaN is not only limited to lighting, but latest innovations also led the development of micro-LEDs, lasers projection and point source. These developments have pushed GaN into the realm of display technology. The miniaturization of the GaN-based micro-LED and integration of GaN on silicon driving the application into fast response photonic integrated circuits (ICs). Most of the recent advancements in GaN LED field would be discussed in detail

In vitro demineralization prevention by fluoride and silver nanoparticles when applied to sound enamel and enamel caries-like lesions of varying severities

Objectives To investigate the effect of fluoride and silver nanoparticles on the prevention of in vitro demineralization of sound enamel and enamel caries-like lesions of varying severities. Methods Caries-like lesions of different severities (1/6/15 days) were created in bovine enamel specimens. One group remained sound. All specimens were demineralized again using a partially saturated acetic acid solution. Mimicking the intra-oral retention of fluoride and silver in vitro, this solution was supplemented with fluoride (0/1/10 ppm) and/or silver nanoparticles (0/10 ppm) in a factorial design. Changes in lesion depth (ΔL) and integrated mineral loss (ΔΔZ) were evaluated by digital transverse microradiography. Data was analyzed using three-way ANOVA. Results Lesion severity significantly affected ΔΔZ and ΔL, after no treatment and after the treatment of fluoride and silver independently (p = 0.012 and p = 0.037, respectively). Fluoride and the fluoride × lesion severity interaction were shown to be significant (p < 0.001) on ΔΔZ and ΔL. Silver nanoparticles significantly affected ΔΔZ (p = 0.041), but not ΔL (p = 0.15). The silver nanoparticles × lesion severity interaction was significant for ΔΔZ and ΔL (p = 0.032 and p = 0.024, respectively). No interaction was observed for ΔΔZ and ΔL between fluoride and silver (p = 0.962 and p = 0.971, respectively) as well as lesion severity and the use of fluoride and silver combined (p = 0.722 and p = 0.158, respectively). Conclusion Fluoride and silver nanoparticles had a significant effect on the prevention of in vitro demineralization of sound enamel and enamel caries-like lesions of varying severities. Clinical significance Fluoride and silver nanoparticles may potentially allow for more tailored caries prevention

Surgical Approaches to Congenital Anomalies of Esophagus

With prevalence of about 1 in 3000 live births, pediatric surgeons commonly deal with esophageal abnormalities, which may provide substantial clinical complications. Surprisingly, the embryologic processes underlying esophageal atresia (EA) with or without tracheoesophageal fistula (TEF), one of the hallmark disease entities of pediatric surgery, have only lately been largely uncovered. When it comes to the treatment of congenital esophageal abnormalities, notably esophageal atresia and tracheoesophageal fistula, surgical methods are essential. In order to address the anatomical abnormalities and restore normal function, surgical correction is often necessary in the care of congenital esophageal anomalies, including esophageal atresia and tracheoesophageal fistula. In this review we are going to cover surgical approaches to repair those malformations, long-term outcomes, and latest developments in esophageal surgical approaches

Physicians’ Practices in Diabetic Nephropathy in Primary Healthcare Centers in Jazan City, Saudi Arabia, 2023

Background and Objectives: Diabetes is one of the most common diseases dealt with by physicians in primary healthcare centers (PHCs). The disease is associated with macrovascular and microvascular complications, especially in those with long disease duration and uncontrolled diabetic nephropathy, which is one of the most common microvascular complications among diabetic patients. This investigation assessed the practices of physicians working at PHCs in terms of diabetic nephropathy screening, management, and referral. Materials and Methods: This study is a cross-sectional investigation targeting physicians working at PHCs in the Jazan region of Saudi Arabia between March and August of 2023. Data were collected via a self-administered questionnaire, which was distributed via online platforms. The questionnaire included sections measuring physicians’ demographic data and associated factors regarding training, the availability of resources, and practices in diabetic nephropathy, including screening, management, and referral. Chi-squared tests were used to assess associations between the practices of physicians and the measured demographics. Result: A total of 234 physicians participated in the investigation. The median age of the participants was 35 years. The adherence level of practice toward diabetic nephropathy according to American Diabetes Association (ADA) guidelines ranged from 40 points (the highest adherence level of participants) to 19 points (the lowest adherence level of participants), with a median of 33 points. Higher adherence levels were noted among physicians in Saudi Arabia, physicians with higher education levels, physicians specializing as family physicians or diabetologists, physicians who reported attending online and on-site training at diabetic centers, physicians who reported continuous access to urine and serum creatinine tests, and physicians who reported continuous access to the American Diabetes Association guidelines (p Conclusions: There are several factors associated with the level of adherence in diabetic nephropathy practice, such as physicians’ education level, specialty, training, and access to guidelines. The findings suggest the need for more training for PHC physicians in the care of patients affected by or at risk of diabetic nephropathy

Prehnite as an indicator mineral in the Wadi Nasb uralitized gabbro, South Sinai, Egypt

We report the first finding of prehnite in the southern Sinai peninsula, in a uralitized gabbro developed at the contact of the appinitic gabbro of the Wadi Nasb mafic intrusion (WNMI) with younger granitic intrusions. Subsolidus reactions with hydrothermal fluids caused the gabbro to gain Al_2O_3 and CaO while losing SiO_2, Fe_2O_3, TiO_2, P_2O_5, Ba, Nb, Zr and Y. Uralitization proceeded through two stages of alteration and mineral replacement. The early stage includes uralitization of pyroxene, formation of new biotite as aggregates of small flakes, transformation of primary amphiboles into actinolite and actinolitic hornblende, and saussuritization of plagioclase. The late stage of alteration is characterized by chloritization of mafic minerals. Apparent crystallization temperatures of the primary relics of pyroxene, hornblende and biotite range from 800–1000 °C, 865–925 °C, and ∼700 °C, respectively, suggesting partial resetting of the biotite exchange thermometer. The early biotite-forming alteration occurred at moderate temperature (300–450 °C), while the late chlorite-forming alteration occurred at low temperature (<300 °C). The prehnite occurs in several forms: (1) fine grained aggregates mostly replacing feldspar and amphibole; (2) prehnite-biotite intergrowths; and (3) small veinlets and vug fillings. The formation of prehnite during the first stage is connected to alteration of pyroxene to secondary amphiboles and of plagioclase to albite, which released the CaO necessary for the development of prehnite. On the other hand, the late stage prehnite probably formed by open-system modification of the chemistry during late-stage fluid interaction

A decade of experience in prescribing hydroxychloroquine and azithromycin: A retrospective analysis of medication queries in a Saudi drug and poison information center

Purpose: To analyze drug information queries related to treatment with hydroxychloroquine (HCQ), chloroquine (CQ), and azithromycin submitted to a local drug and poison information center in Riyadh, Saudi Arabia. Methods: This retrospective study explored HCQ-, CQ-, and azithromycin-related inquiries submitted to the Drug and Poison Information Center at the Security Forces Hospital Program, Riyadh, Saudi Arabia. These inquiries were analyzed quantitatively and qualitatively. The quantitative analysis included the frequency of each request per year, the profession of the requesters, and the source material classification. A thematic analysis was also performed to categorize requests from healthcare professionals. Results: The Drug and Poison Information Center received 10,685 usable inquiries between 2005 and 2018. There were 160 CQ-, HCQ-, and azithromycin-related queries. Most requests were made by pharmacists (61.25 %). The main sources used to answer the queries were tertiary (92.31 %) and primary (7.69 %) sources. In the dataset, three major topics were identified: administration and dosing, safety, and pregnancy and lactation, each associated with a query subset. Conclusion: These results emphasize the importance of continued education on antimicrobial agents in general, and HCQ, CQ, and azithromycin in particular. The three items have been identified as focus areas that policymakers can us to ensure the quality of future medication prescriptions

In vitro demineralization prevention by fluoride and silver nanoparticles when applied to sound enamel and enamel caries-like lesions of varying severities

Objectives To investigate the effect of fluoride and silver nanoparticles on the prevention of in vitro demineralization of sound enamel and enamel caries-like lesions of varying severities. Methods Caries-like lesions of different severities (1/6/15 days) were created in bovine enamel specimens. One group remained sound. All specimens were demineralized again using a partially saturated acetic acid solution. Mimicking the intra-oral retention of fluoride and silver in vitro, this solution was supplemented with fluoride (0/1/10 ppm) and/or silver nanoparticles (0/10 ppm) in a factorial design. Changes in lesion depth (ΔL) and integrated mineral loss (ΔΔZ) were evaluated by digital transverse microradiography. Data was analyzed using three-way ANOVA. Results Lesion severity significantly affected ΔΔZ and ΔL, after no treatment and after the treatment of fluoride and silver independently (p = 0.012 and p = 0.037, respectively). Fluoride and the fluoride × lesion severity interaction were shown to be significant (p < 0.001) on ΔΔZ and ΔL. Silver nanoparticles significantly affected ΔΔZ (p = 0.041), but not ΔL (p = 0.15). The silver nanoparticles × lesion severity interaction was significant for ΔΔZ and ΔL (p = 0.032 and p = 0.024, respectively). No interaction was observed for ΔΔZ and ΔL between fluoride and silver (p = 0.962 and p = 0.971, respectively) as well as lesion severity and the use of fluoride and silver combined (p = 0.722 and p = 0.158, respectively). Conclusion Fluoride and silver nanoparticles had a significant effect on the prevention of in vitro demineralization of sound enamel and enamel caries-like lesions of varying severities. Clinical significance Fluoride and silver nanoparticles may potentially allow for more tailored caries prevention

Structural Transition in SrZnO Laser Pulse Deposited Alloy

International audienc

Rupture characteristics of a small-sized earthquake (M W 4.2), onshore the south Red Sea, Saudi Arabia

The present study is based on the use of Empirical Green's Function (EGF) deconvolution technique to retrieve the slip distribution of the 2014 M w 4.2 Jizan earthquake, Saudi Arabia. Two datasets of complex Source Time Functions (STFs) were retrieved using two appropriate EGF events. We inverted the STF datasets to recover the slip distribution over both nodal planes, using the Bayesian modeling followed by a linear least-squares method. The inversion was performed assuming both planes as the fault plane and examined the goodness of fit for each nodal plane. Based on a series of finite-source inversions using different rupture velocities, we resolved the rupture velocity at 2.7–2.8 km/s and the fault plane of NNW trending; paralleling the Red Sea rift. Using the estimated rupture velocities and the preferred fault plane, we imaged quite similar slip models, exhibiting two slip patches located to the updip and downdip directions from the hypocentre. The spatiotemporal slip distributions revealed a complex rupture history of such small-sized earthquake is likely to that reported for large-sized earthquakes. A seismic moment of 2.8–3.2E+15 NM and a corresponding moment magnitude of 4.2-4-3 are inferred. The stress drops obtained from the slip distribution models were 2.2–2.5 MPa; indicating a typical value that characterized the plate-boundary earthquakes

Evidence for inflammation in normal appearing brain regions in patients with growing sporadic vestibular schwannoma: a PET study

Background: Non-auditory symptoms can be a prominent feature in patients with sporadic vestibular schwannoma (VS), but the cause of these symptoms is unknown. Inflammation is hypothesized to play a key role in the growth and symptomatic presentation of sporadic VS, and in this study we investigated through translocator protein (TSPO) PET whether inflammation occurred within the ‘normal appearing’ brain of such patients and its association with tumor growth. Methods: Dynamic PET datasets from fifteen patients with sporadic VS (8 static, 7 growing) who had been previously imaged using the TSPO tracer [11C](R)-PK11195 were included. Parametric images of [11C](R)-PK11195 binding potential (BPND) and the distribution volume ratio (DVR) were derived and compared across VS growth groups within both contralateral and ipsilateral grey (GM) and white-matter (WM) regions. Voxel-wise cluster analysis was additionally performed to identify anatomical regions of increased [11C](R)-PK11195 binding. Results: Compared with static tumors, growing VS demonstrated significantly higher cortical (GM, 1.070 vs 1.031, p = 0.03) and whole brain (GM&amp;WM,1.045 vs 1.006, p = 0.03) [11C](R)-PK11195 DVR values. Voxel-wise analysis supported the region-based analysis and revealed clusters of high TSPO binding within the precentral, postcentral, and prefrontal cortex in patients with growing VS. Conclusion: We present the first in vivo evidence of increased TSPO expression and inflammation within the brains of patients with growing sporadic VS. These results provide a potential mechanistic insight into the development of non-auditory symptoms in these patients and highlight the need for further studies interrogating the role of neuroinflammation in driving VS symptomatology. <br/