Reduction In Mobility Research Articles

The degradation mechanism of high power S-band AlGaN/GaN HEMTs under high temperature

Abstract The radio frequency (RF) degradation mechanism under high temperature is proposed in this paper. The saturated output power (P sat), power added efficiency (PAE) and gain of the HEMTs deteriorate significantly under high power dissipation operation conditions, which contribute to an elevation of the junction temperature (T j). The high T j causes a negative shift of the threshold voltage and a reduction of electron mobility, as well as enhancing the trapping effects of the devices. As a result, the P sat and PAE of the high-power HEMTs (P sat = 152 W) decreased by 0.76 dB and 8.3%, respectively, which is more severe compared to low-power HEMTs (P sat = 20 W), where P sat and PAE reduced by 0.16 dB and 3.1% when the operation temperature was increased from 25 °C to 150 °C. By increasing the gate-to-drain distance from 1.625 to 2.175 μm, drain current stability and high temperature reverse bias reliability are improved. The results demonstrate that the trapping effect can be suppressed by decreasing the electric field under the gate; therefore, the RF output characteristics are boosted by 1.2 W, 1 dB and 2.6% for a device with gate width of 11.52 mm.

RELATION BETWEEN δ13С, δ18О AND REE CONTENT IN CARBONATITES OF THE TOMTOR COMPLEX, SAKHA REPUBLIC (YAKUTIA)

The paper reports the comprehensive study of phosphorus-rare metal (polymineral) carbonatites (I) and rare metal (ankerite) carbonatites (II) of the Tomtor massif based on ICP-MS, XRF, XRF-SI, SEM methods and isotope determination of C, O and 86Sr/87Sr. With a similar mineral composition, the REE+Y content in carbonatites (I) averages 0.38 wt. %, and in carbonatites (II) it is 1.3 wt. %. The δ18О-δ13С diagram provides the C and O isotopic compositions of carbonatites (I) and (II) as two intersecting trends: (I) carbonates from wells 4041, 6151, 115-117 represent the secondary generation of carbonates derived with the deuterium fluid involved; (II) depicts transformation of carbonate by low-T fluid, with fluid/rock ratio = 5. The study identified an increase in the REE and δ18O contents in carbonatites as the temperature of their formation decreases and enrichment of rocks with REE minerals, associated with REE mobility reduction in the fluid while the temperature is decreasing.

Leaching Studies for the Assessment of Individual Immobilization Potential of Chrysopogon zizanioides Root Micro Powder from Lead, Cadmium and Chromium Contaminated Soil

ABSTRACT Contemporary issues of ground contamination, exacerbated by elevated heavy metal levels due to industrial activities and improper waste disposal, significantly impact soil properties, the biosphere, and result in various geotechnical problems. This study delves into the efficacy of Chrysopogon zizanioides (vetiver) root micro powder (VRMP) in immobilizing Lead (Pb), Cadmium (Cd), and Chromium (Cr) within contaminated soil to prevent groundwater pollution and bioavailability. Leaching experiments were conducted to evaluate the individual immobilization of heavy metals and determine the optimal VRMP dosage, testing four dosages (0%, 1%, 5%, and 10%) for their effectiveness in immobilizing Pb, Cd, and Cr in contaminated soil. The findings suggest that addition of VRMP led to an increase in pH, facilitating the enhanced immobilization of Pb, Cd, and Cr from the contaminated soil due to the reduction in mobility of these metals. Soil treated with 10% VRMP exhibited exceptional immobilization efficiency, achieving over 90% removal across all treatments. However, agglomeration caused the leaching process to take slightly longer. Consequently, a 5% VRMP dosage is considered optimal. In conclusion, vetiver root micro powder promotes a sustainable approach to immobilize Pb, Cd, and Cr in contaminated soils, underscoring the effectiveness of eco-friendly methodologies.

Thermal atomic layer deposition-processed InHfZnO thin film transistors with excellent stability

In recent years, the downscaling of transistors has sparked considerable interest in the advancement of amorphous oxide semiconductors, particularly indium-hafnium-zinc oxide (IHZO) has remarkable potential in applications such as high-resolution displays and 3D NAND. For the first time, we propose the fabrication of IHZO thin film transistors (TFTs) via thermal atomic layer deposition (TH-ALD). The preparation, electrical properties, and stability of IHZO TFTs are investigated. The performance of TFT deposited at 250 °C and annealed in N2 atmosphere at 300 °C exhibits a high field-effect mobility (μ) of 22.53 cm2/Vs, a high Ion/Ioff of ∼107, a low threshold voltage (Vth) of 0.15 V, and a minimum subthreshold swing (SS) of 0.24 V/decade. Furthermore, the threshold voltage shifts (ΔVth) in TFTs annealed in N2 and O2 are 0.31 and 0.16 V, respectively. These enhancements are attributed to the defects suppression and remaining ionized oxygen vacancies result in increased electron concentration in N2-annealed films. In comparison, O2 annealing causes a reduction in field effect mobility but concurrently enhances stability due to the direct passivation of defects, which leads to fewer oxygen vacancies. Additionally, Hf content can also impact the performance of TFT devices, even a small addition of Hf also results in the effective reduction of the carrier concentration. These findings provide valuable insights into the device mechanism of IHZO TFTs, presenting a novel avenue for comprehending and augmenting their overall performance.

Differential MRGPRX2-dependent activation of human mast cells by polymyxins and octapeptins

The emergence of multi-drug resistant Gram-negative bacteria has led to renewed interest in the antimicrobial activity of polymyxins and novel polymyxin analogues (e.g. nonapeptides and octapeptin). In some individuals, clinically used polymyxins can cause acute hypersensitivity reactions through mast cell activation, with a recent study attributing this effect to activation of the MAS-related G protein-coupled receptor X2 (MRGPRX2). In the present study, HEK293 cells expressing human MRGPRX2 and the human mast cell line LAD2 were used to characterize the activity of the broader family of polymyxins. Octapeptin C4, polymyxin B and colistin produced concentration-dependent calcium mobilization, degranulation, and CCL-2 (MCP-1) release in LAD2 mast cells, with the former being highly potent. CRISPR-Cas9 knockdown of MRGPRX2 in LAD2 cells and a MRGPRX2 inverse agonist caused a significant reduction in calcium mobilization, degranulation, and CCL-2 release, demonstrating dependency on MRGPRX2 expression. In contrast, polymyxin nonapeptides were far less potent calcium mobilisers and failed to induce functional degranulation in LAD2 cells. Our results confirm that activation of mast cells induced by polymyxin-related antibiotics is MRGPRX2-dependent and reveal that octapeptin C4 might be more liable, whilst nonapeptides are less liable, to trigger immediate hypersensitivity reactions clinically. The mechanism underpinning the difference in MRGPRX2 activation between polymyxin-related antibiotics is important to better understand as it may help design new, safer polymyxins and guide the optimal clinical use of existing polymyxin drugs.

Enhancement of interaction between Shenhua coal and GON-based dispersant with “surface-to-surface” adsorption by regulating the oxidation degree of GON: Experiments and simulations

The present study focuses on the synthesis of several graphene oxide nanosheet (GON)-based dispersants with an adsorption mode of “surface-to-surface” for the preparation of Shenhua coal (SC) water slurry (SCWS), achieved by grafting allyl polyoxyethylene ether (APEG) onto GON edges with varying degrees of oxidation using emulsion polymerization and esterification techniques. The impacts of the oxidation degree of GON on its structural characteristics and the performance of GON-based dispersants in SCWS were comprehensively assessed through a range of experimental techniques, alongside molecular dynamics (MD) simulations. Results demonstrated that with the increase in oxidation degree, there was an elevation of oxygen-containing groups, in which the content of COH decreased while the content of COC increased. Among all dispersants, GA-2, which was synthesized using GON-2 as the raw material with a graphite-to-KMnO4 mass ratio of 1:2.5, exhibited superior viscosity-reducing and stabilizing abilities compared to other dispersants. All SCWSs demonstrated pseudoplastic fluid behavior and showed good agreement with the Herschel-Bulkley model. After the adsorption of dispersants in SC, both the Zeta potential and surface wettability of SC significantly improved, especially with GA-2. The interaction mechanism between the dispersant and SC was analyzed by establishing and employing three adsorption models (M-1, M-2, and M-3). The interfacial adsorption structure confirmed that the dispersant exhibited “surface-to-surface” mode on coal through hydrophobic interaction, hydrogen bonding, and π–π interaction. Energy studies revealed that M-2 with the highest Eads (−105.31 kcal/mol) demonstrated superior adsorption strength compared to M-1 and M-3. Investigations into water molecule mobility revealed that the interaction between the GON-based dispersant and SC resulted in a reduction of water molecule mobility, thereby promoting water molecule aggregation to facilitate the formation of hydration films and enhance SCWS stability. In summary, an optimal oxidation degree of GON was found to be crucial for enhancing the performance of GON-based dispersants; higher oxidation levels may hinder dispersant adsorption on coal surfaces by converting hydroxyl and carboxyl groups into epoxide groups, thus impairing the conjugated structure.

Middle Stone Age technological organisation from MIS 5 at Mertenhof Rockshelter, South Africa

Lithic technological organisation within the southern Africa Early Middle Stone Age (∼315,000–80,000 years ago) has seen relatively little investigation owing to the subtly of technological change, frequent use of locally derived raw materials, and the archaeological spatio-temporal discontinuity. This has resulted in relatively limited use of explanatory models for technological variability, including mobility, provisioning, tool production, and core reduction strategies. This paper uses 2952 artefacts to test the lithic technological organisation across Marine Isotope Stage 5 units of Mertenhof Rockshelter. Here we argue that the scales and concepts currently used to approach Early Middle Stone Age technology requires reconsideration. The Mertenhof sequence exhibits high proportions of non-local raw materials with their transport reflective of tactical adjustments within relatively stable mobility, provisioning, and reduction strategies. We demonstrate that Early Middle Stone Age populations maintained a diverse array of tactical solutions across these strategic domains, offering a durable and flexible strategy that would be adapted to changing contexts.

Analyzing Foam Injection Dynamics in Porous Media: A Combined Computational and Experimental Approach

The study of foam injection dynamics into porous media holds numerous applications, with its primary use being the optimization of the oil extraction process. Additionally, it finds utility in various other domains, including soil decontamination techniques. This study focuses on evaluating foam injection through low-cost experiments and computational models. The model integrates a classic two-phase immiscible fluid flow in a porous media framework, augmented by a mobility reduction factor to simulate foam’s impact on gas phase mobility. Simple experiments were conducted to assess water displacement using both gas and gas-foam injection methods. Results revealed that while gas injection tends to form preferential paths rapidly, leading to gas disruption, foam injection generates a more compact front, enhancing sweep efficiency by mitigating preferential path formation. The computational model successfully reproduced the experimental findings qualitatively. This research introduces a cost-effective experiment suitable for didactic purposes, illustrating complex concepts and underscoring the complementary nature of experimental and computational methodologies in advancing engineering techniques.

Health-Related Quality-of-Life Utility Values in Adults With Late-Onset Pompe Disease: Analyses of EQ-5D Data From the PROPEL Clinical Trial

Background: Pompe disease is a rare lysosomal storage disorder, leading to accumulation of glycogen characterized by muscle weakness, fatigue, pain, and, in the longer term, a requirement for ventilatory and ambulatory support, and early mortality if untreated. Clinical evidence suggests that enzyme replacement therapy improves health outcomes for adults with late-onset Pompe disease (LOPD). PROPEL was a Phase 3, double-blind, randomized controlled trial, which evaluated cipaglucosidase alfa plus miglustat, vs alglucosidase alfa plus placebo in 123 adult patients with LOPD (clinicaltrials.gov: NCT03729362). Objectives: To analyze EQ-5D health-related quality of life (HRQoL) utility data from PROPEL. Methods: Multilevel modeling techniques (mixed regression methods) were used to analyze PROPEL EQ-5D-3L estimates and predict utility values for 7 health states previously identified in an economic evaluation for LOPD. In PROPEL, EQ-5D-5L values were assessed at screening and at weeks 12, 26, 38, and 52. EQ-5D-5L utility values were mapped to EQ-5D-3L values using the van Hout algorithm as recommended by the EuroQoL and the National Institute of Health and Care Excellence position statement at time of analysis. UK population tariffs were applied for all EQ-5D utility valuations. Utility values were predicted according to 6-minute walk distance (6MWD) and percent predicted sitting forced vital capacity. Results: The mixed model predicted that EQ-5D-3L utility values for patients who could walk >75 m with LOPD ranged between 0.55 and 0.67 according to patient 6MWD and respiratory function. In this analysis, patients with a 6MWD ≤75 m, consistent with a health state requiring wheelchair support in the economic analysis, had a predicted utility value of 0.49. There were few patients in PROPEL who could walk ≤75 m at any time point in the study, hence, these utility estimates should be interpreted with caution. EQ-5D-3L utility estimates from PROPEL were consistent with previously reported EQ-5D-3L values in LOPD. Conclusions: Overall, the results from our analysis indicate that important HRQoL losses are associated with reductions in mobility and respiratory function for patients with Pompe disease. The study provides important evidence of HRQoL utility values for patients with advanced LOPD, a population for whom published data are limited.

Health-Related Quality-of-Life Utility Values in Adults With Late-Onset Pompe Disease: Analyses of EQ-5D Data From the PROPEL Clinical Trial.

Background: Pompe disease is a rare lysosomal storage disorder, leading to accumulation of glycogen characterized by muscle weakness, fatigue, pain, and, in the longer term, a requirement for ventilatory and ambulatory support, and early mortality if untreated. Clinical evidence suggests that enzyme replacement therapy improves health outcomes for adults with late-onset Pompe disease (LOPD). PROPEL was a Phase 3, double-blind, randomized controlled trial, which evaluated cipaglucosidase alfa plus miglustat, vs alglucosidase alfa plus placebo in 123 adult patients with LOPD (clinicaltrials.gov: NCT03729362). Objectives: To analyze EQ-5D health-related quality of life (HRQoL) utility data from PROPEL. Methods: Multilevel modeling techniques (mixed regression methods) were used to analyze PROPEL EQ-5D-3L estimates and predict utility values for 7 health states previously identified in an economic evaluation for LOPD. In PROPEL, EQ-5D-5L values were assessed at screening and at weeks 12, 26, 38, and 52. EQ-5D-5L utility values were mapped to EQ-5D-3L values using the van Hout algorithm as recommended by the EuroQoL and the National Institute of Health and Care Excellence position statement at time of analysis. UK population tariffs were applied for all EQ-5D utility valuations. Utility values were predicted according to 6-minute walk distance (6MWD) and percent predicted sitting forced vital capacity. Results: The mixed model predicted that EQ-5D-3L utility values for patients who could walk >75 m with LOPD ranged between 0.55 and 0.67 according to patient 6MWD and respiratory function. In this analysis, patients with a 6MWD ≤75 m, consistent with a health state requiring wheelchair support in the economic analysis, had a predicted utility value of 0.49. There were few patients in PROPEL who could walk ≤75 m at any time point in the study, hence, these utility estimates should be interpreted with caution. EQ-5D-3L utility estimates from PROPEL were consistent with previously reported EQ-5D-3L values in LOPD. Conclusions: Overall, the results from our analysis indicate that important HRQoL losses are associated with reductions in mobility and respiratory function for patients with Pompe disease. The study provides important evidence of HRQoL utility values for patients with advanced LOPD, a population for whom published data are limited.

The increase of the scattering at high electric fields in multilayer ReS2 FETs: Output characteristics and 1/f noise

Field-effect transistors (FETs) employing two-dimensional (2D) materials have attracted significant attention as a potential alternative to silicon FETs. Among these materials, multilayer rhenium disulfide (ReS2) has emerged as a focal point of interest owing to its distinctive direct bandgap properties. While there is extensive research on the electrical characteristics and doping, studies on the changes in electrical properties during scale-down for practical applications are insufficient. In this study, we investigated the mobility reduction of ReS2 FETs at high drain bias of ReS2 FETs by comparing the different channel lengths of 0.24 μm and 1.5 μm. A reduction in mobility was observed for the shorter channel length, attributed to the enhanced scattering factor at high electric field. To assess the impact of scattering degradation, we conducted a low-frequency noise analysis at drain-source voltage (VDS) = 0.4 V and VDS = 3.0 V for the 0.24 μm length FET. The decrease of the Hooge parameter (αH) at high VDS was observed, which was attributed to an augmentation in Coulomb scattering. This study observed mobility degradation under high electrical fields during scale-down and identified the cause of mobility degradation through low-frequency noise analysis. This contributes to scaling down for practical applications of 2D FETs.

The contribution of employer changes to aggregate wage mobility

Abstract Wage mobility reduces the persistence of wage inequality. We develop a framework to quantify the contribution of employer-to-employer movers to aggregate wage mobility. Using three decades of German social security data, we find that inequality increased while aggregate wage mobility decreased. Employer-to-employer movers exhibit higher wage mobility, mainly due to changes in employer wage premia at job change. The massive structural changes following German unification temporarily led to a high number of movers, which in turn boosted aggregate wage mobility. Wage mobility is much lower at the bottom of the wage distribution, and the decline in aggregate wage mobility since the 1980s is concentrated there. The overall decline can be mostly attributed to a reduction in wage mobility per mover, which is due to a compositional shift toward lower-wage movers.

Transduced Olfactory Mucosa Cells Expressing Nerve Growth Factor for the Therapy of Experimental Spinal Cord Cysts.

A new gene-cell construct expressing nerve growth factor (NGF) has been developed. After obtaining engineered adenovectors Ad5-RGD-CAG-NGF and Ad5-RGD-CAG-EGFP, transduction efficiency and transgene expression were studied and multiplicity of infection was determined. The efficacy of transduced human olfactory ensheathing cells expressing NGF in restoring motor activity in rats has been shown in a limited period of time. Improved rat hindlimb mobility and cyst size reduction after gene-cell construct transplantation were more likely due to the cellular component of the construct.

An Overview of Hydrogen Production from Renewable Sources and Its Main Applications

AbstractThere is a misconception that sustainability is only related to greenhouse gas emissions into the atmosphere, and that this is the only risk to which the planet is exposed. Sustainability is a multidimensional concept and must advance simoutaneously on several fronts, such as the urgent need to increase energy, clean water, clean air, food, mobility, health, and poverty reduction. All the problems of these multi‐dimensions are aggravated by the continuous growth of the world population, mainly in economic and socio‐environmental issues. However, the biggest challenge is to increase the supply of clean energy from renewable sources, as all other dimensions of sustainability depend on energy supply and policy decisions. The consumption of fossil fuels has supplied the current energy demand by approximately 87 %. Still, there are predictions of depletion, and the effects caused on the environment by the production of greenhouse gases bring significant economic losses. In this review, we will address the most common methods for hydrogen production, as well as its main technological applications in organic synthesis and for energy generation.

Can nutraceuticals counteract the detrimental effects of the environment on male fertility? A parallel systematic review and expert opinion.

Male fertility relies on a complex physiology that may be negatively influenced by lifestyle, diet, and environment. The beneficial effect of nutraceuticals on male fertility is a debated claim. The aim of this study was to assess if the positive effect of nutraceuticals can counteract the negative effects of the environment on male fertility. PubMed®/MEDLINE®, Embase and Cochrane Database were searched (September-October 2023), along with crosschecking of references and search for ongoing studies of the effects of the environment and nutraceuticals on male fertility, in accordance with the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Several environmental factors such as microplastic and other endocrine-disrupting chemicals and climate changes may affect the sperm quality in terms of reduction of sperm count number, mobility and altered morphology and thereby reduce male fertility. On the other hand, new evidence demonstrates that a balanced diet rich in antioxidants and essential nutrients, together with minimized exposure to environmental toxins, may improve male fertility and reproductive health. Several nutraceutical compounds proved a protective role against negative environmental effects on male fertility. Available evidence confirms that the environment may negatively impact male fertility, and this impact is estimated to rise in the forthcoming years. On the other hand, new data indicate that nutraceuticals may have a protective role against the negative impact of environmental factors on male fertility. The need for future studies to monitor and explore these aspects of men's health cannot be underestimated.

Bio-inspired helicoidal hemp/basalt/polyurethane rubber bio-composites: Experimental, numerical and analytical ballistic impact study with residual velocity prediction using artificial neural network

Recent body armour trends emphasize mobility, flexibility, and cost reduction while maintaining ballistic effectiveness through the use of natural fiber composite. This study evaluates the ballistic impact performance of soft and hard armor using experimental, analytical, numerical, and machine learning methods. We developed a soft armor bio-composite using monolithic, hybrid, and helicoidal structured Hemp (H)/Basalt (B)/Polyurethane (PU) rubber and tested its V50 ballistic limit according to Millitary-Standred-662 F. For hard armour, a multi-layer armor system (MAS) consisting of Al2O3/SiC ceramic, intermediate soft armour bio-composites, and an Aluminum (Al)-5052 plate backing was tested with armour-piercing bullets as per National Institute of Justice (NIJ)-0101.06 standards (Level IV). Soft armor performance was evaluated using macro-homogeneous finite element (FE), the Ipson-Retch analytical, and an Artificial Neural Network (ANN) regression model. Results showed minimal discrepancies from experimental data, with differences of 13.33 %, 12.08 %, and 8.08 % in V50 ballistic limit. The mechanical and thermal behaviors of bio-composites were assessed using un-notched Charpy, FTIR, and TGA methods. Helicoidal laminates improved Charpy toughness by 9.44 %, 19.30 %, and 40.28 % compared to hybrid and monolithic ([H]15 and [H]10) laminates, and exhibited lower weight reduction at high degradation temperature of 395.76 ℃. Helicoidal laminates increased V50 ballistic performance by 155.80 %, 76.22 %, and 16.61 % compared to [H]10, [H]15, and hybrid laminates, respectively. Due to spiral load distribution reduces stress concentration and enhanced the damage resistance of the laminate. Stand-alone soft armor demonstrates crater formation and radial cracks (petaling) due to fiber wedging and the shearing effect of a bullet. In conclusion, MAS revels a maximum back face deformation (BFD) of 18.06 mm. Al2O3/Helicoidal/Al-plate MAS reduced weight and cost by 69.21 %, and 233.72 % compared to Kevlar™-based MAS, promoting sustainable, lightweight, economical designs. Due to its higher fracture toughness and lower density, SiC ceramic in MAS provides lower trauma and further reduced weight compared to Al2O3 ceramic.

HCV testing and linkage to care for hepatitis C virus infection for marginalized drug user populations attending a harm reduction service in Bologna, Italy.

Our aim was to estimate the prevalence of HCV in a highly vulnerable population of substance users living with social difficulties and marginality who came into contact with the mobile harm reduction service in the city of Bologna (Northern Italy). Testing was offered in a van (mobile unit) by using a point-of-care HCV antibody test. For the HCV RNA test, the Xpert HCV Viral Load Fingerstick Test was used. Participants with a detectable HCV RNA were accompanied within two weeks to the Infectious Diseases Department Sant' Orsola Hospital Bologna to start HCV treatment. With regard to the main study findings, 54% reported having never been HCV tested before; a prevalence of HCV RNA of 6% among all participants and 22% among those injecting drugs was found; among the HCV RNA positive participants, 80% were accompanied to treatment. Our study suggests that mobile harm reduction services, in networks with healthcare facilities, are able to offer a continuous HCV screening service and linkage to care for people with drug use living in socially marginalized conditions.

Comparison of the researched analyses evaluating the physiotherapy of the pain with a cause in the region of the cervical spine

Introduction. Neck pain is a common musculoskeletal problem. This individual and socio-economic health problem is associated with a reduction in daily activities, a reduction in labour productivity and an impact on quality of life levels. Objective. To evaluate the effectiveness of the therapy of non-specific pain originating from the cervical region in terms of the applied physiotherapy methods. Methods. 40 research articles published in 2018-2023 in journals with registration in databases Web of Science, Science Direct and Scopus were included in the research. Results. The most frequent target studied was the education of patients on ergonomics, correct posture and home exercises. The preparation phase of therapy included the administration of thermotherapy and electrotherapy – ultrasound or transcutaneous electrical nerve stimulation (TENS), classical massage, administration of non-steroidal anti-inflammatory drugs. The techniques often used were manipulation and/or mobilization, trigger and tender points therapy – acupressure, acupuncture, dry needle application. Among the therapeutic methods, the most frequently chosen are exercises in the form of pilates, yoga, Alexander technique, sensomotor training, proprioceptive neuromuscular facilitation, Jakobson progressive muscle relaxation. Reduction of painful mobility was addressed by the application of local immobilization and kineziotaping. Conclusion. According to the results of our analysis, the combination of several physiotherapy techniques and methods appears to be significantly effective for reducing pain and improving quality of life.

Class III correction and enhanced periodontal health with aligner treatment in a 53-year-old patient.

In this case report, we describe the successful camouflage treatment of a 53-year-old female with dental and skeletal Class III malocclusion combined with anterior crossbite, gingival recession, and mobility of the lower incisors, using clear aligners. The treatment involved periodontal debridement followed by orthodontic treatment. The mandibular posterior teeth were distalized to correct the anterior crossbite and to establish Class I molar relationships. During treatment, the mandibular incisors were intruded, and the mandibular occlusal plane underwent a clockwise rotation due to slight extrusion of the maxillary buccal segments and distalization of the mandibular posterior teeth. Following treatment, all objectives were achieved, including resolution of the anterior crossbite, significant reduction of gingival recession and tooth mobility, and improved functional occlusion. The dental and skeletal Class III malocclusion was corrected, and the marginal alveolar bone dehiscence was significantly reduced. The results remained stable over a 3-year retention period, with enhanced molar intercuspation and gingival growth progression. This case adds to the evidence supporting the adaptability and effectiveness of clear aligners in treating orthodontic patients with compromised periodontium. The treatment outcomes support that orthodontic treatment using clear aligners, combined with periodontal monitoring, can assist in managing alveolar bone defects, gingival recession, and tooth mobility.

Examining human mobility changes during COVID-19 across socioeconomic groups: a comparative analysis of San Diego County and New York City

The COVID-19 pandemic brought unprecedented changes to various aspects of daily life, profoundly affecting human mobility. These changes in mobility patterns were not uniform, as numerous factors, including public health measures, socioeconomic status, and urban infrastructure, influenced them. This study examines human mobility changes during COVID-19 in San Diego County and New York City, employing Latent Profile Analysis (LPA) and various network measures to analyze connectivity and socioeconomic status (SES) within these regions. While many COVID-19 and mobility studies have revealed overall reductions in mobility or changes in mobility patterns, they often fail to specify ’where’ these changes occur and lack a detailed understanding of the relationship between SES and mobility changes. This creates a significant research gap in understanding the spatial and socioeconomic dimensions of mobility changes during the pandemic. This study aims to address this gap by providing a comprehensive analysis of how mobility patterns varied across different socioeconomic groups during the pandemic. By comparing mobility patterns before and during the pandemic, we aim to shed light on how this unprecedented event impacted different communities. Our research contributes to the literature by employing network science to examine COVID-19’s impact on human mobility, integrating SES variables into the analysis of mobility networks. This approach provides a detailed understanding of how social and economic factors influence movement patterns and urban connectivity, highlighting disparities in mobility and access across different socioeconomic groups. The results identify areas functioning as hubs or bridges and illustrate how these roles changed during COVID-19, revealing existing societal inequalities. Specifically, we observed that urban parks and rural areas with national parks became significant mobility hubs during the pandemic, while affluent areas with high educational attainment saw a decline in centrality measures, indicating a shift in urban mobility dynamics and exacerbating pre-existing socioeconomic disparities.