COVID-19 vaccine hesitancy has been particularly high among immigrant populations, whose experience is shaped by a history of racism and discriminations, and distrust of the healthcare system. In ...this study we draw from the Theory of Planned Behavior to examine COVID-19 vaccine hesitancy among immigrants in Chicago.
A mixed-methods approach comprising of both focus groups and a health survey was conducted from February to August 2022. Five focus groups were held (N = 35) among Black, Asian and Arab/Palestine participants to understand attitudes and beliefs around the COVID-19 vaccine. Focus groups were analyzed using a modified template approach to text analysis. Based on these findings and themes, we developed a survey that was conducted among 413 immigrants from the mentioned communities. We used hierarchical ordinal regression analyses to examine the relationship between COVID-19 vaccine hesitancy and vaccination status.
Qualitative analysis suggest that the major factors influencing COVID-19 vaccine hesitancy included fear of adverse reactions, misinformation around COVID-19 and the vaccine, negative social norms around vaccination, and external pressure to get vaccinated. From our quantitative analysis we found that 24% of participants were unvaccinated, 5% were partially vaccinated, 32.3% were vaccinated but not boosted, and 39% were vaccinated and boosted for COVID-19. Hierarchical regression models suggest that immigrants who hold negative attitudes and social norms around the COVID-19 vaccine are less likely to vaccinate.
Understanding vaccine hesitancy among immigrants allows for the creation of culturally and linguistically tailored education that can be utilized to increase vaccine confidence and uptake.
As the aviation industry seeks sustainable propulsion solutions, innovative technologies have emerged, among which rim-driven fan (RDF) systems hold notable promise. This comprehensive review paper ...deeply investigates RDF technology, uncovering its principles, benefits, and transformative potential for aviation propulsion. Amid escalating concerns about greenhouse gas emissions, the aviation sector’s shift towards electric propulsion has gained impetus. RDF technology has emerged as a beacon of optimism, heralding the prospect of energy-efficient and eco-conscious air travel. Navigating the slower development pace of RDF technology for aerospace applications, this paper draws insights from analogous marine technologies and relevant literature. Merging these realms, this paper meticulously examines RDF systems, spotlighting their unique attributes, with particular emphasis on the rim-driven configuration and its fundamental design principles. This review delves into the progressive strides accomplished in RDF’s evolution, encompassing the spectrum from evolving electric motor variants to intricate design considerations, strategic noise and vibration management, innovative control methodologies, advancements in bearing technology, and the strategic integration of finite element analysis (FEA) and computational fluid dynamics (CFD) for comprehensive performance optimization. In the context of aviation’s electrification journey, the exploration of RDF technology marks a pivotal inflection point. This paper concludes by succinctly encapsulating pivotal insights, accentuating RDF technology’s central role in reshaping aviation’s propulsion paradigm. As the aviation sector charts a course towards sustainable progress, the lessons gleaned from RDF technology are poised to chart the trajectory of aviation’s environmental transformation.
Dioctophyma renale is a parasite that affects the kidney of dogs and other species. The infection is acquired by ingestion of larvae that may be present in fish, frogs or aquatic annelids. This ...parasite is usually found in the right kidney and can also be seen in the left kidney, abdominal cavity, subcutaneous tissue, bladder and rarely in the testicles. The infection is usually asymptomatic and clinical signs such as inappetence, dysuria and renal colic may occur. Diagnosis is made by the presence of parasite eggs in the urine, imaging tests, and in most cases performed by necropsy, or findings during surgical procedures. The recommended treatment is surgical removal of the nematode, in early diagnosed cases, and in late cases, nephrectomy of the affected kidney. This study aimed to report a case of dioctophimosis in a dog in the city of Valença, RJ, where nephrectomy of the affected kidney was performed after parasitosis was diagnosed by ultrasound examination.
Dioctophyma renale es un parásito que afecta el riñón de los perros y otras especies. La infección se adquiere por la ingestión de larvas que pueden estar presentes en peces, ranas o anélidos acuáticos. Este parásito generalmente se encuentra en el riñón derecho y también se puede ver en el riñón izquierdo, la cavidad abdominal, el tejido subcutáneo, la vejiga y rara vez en los testículos. La infección suele ser asintomática y pueden aparecer signos clínicos como inapetencia, disuria y cólico renal. El diagnóstico se realiza por la presencia de huevos de parásitos en la orina, exámenes de imágenes y, en la mayoría de los casos, realizadas por necropsia o hallazgos durante los procedimientos quirúrgicos. El tratamiento recomendado es la extirpación quirúrgica del nematodo, en los casos de diagnóstico temprano y, en los casos tardíos, la nefrectomía del riñón afectado. Este estudio tuvo como objetivo informar un caso de dioctofimosis en un perro en la ciudad de Valença, RJ, donde se realizó la nefrectomía del riñón afectado después de que se diagnosticara parasitosis mediante examen de ultrasonido.
O Dioctophyma renale é um parasita que acomete o rim de cães e outras espécies, sendo a infecção adquirida pela ingestão de larvas que podem estar presentes em peixes, rãs ou anelídeos aquáticos. Esse parasita normalmente é encontrado no rim direito, podendo ser observado também em rim esquerdo, cavidade abdominal, tecido subcutâneo, bexiga e raramente nos testículos. A infecção geralmente apresenta-se assintomática, podendo ocorrer sinais clínicos como inapetência, disúria e cólica renal. O diagnóstico é feito através da presença de ovos do parasita na urina, exames de imagem, e na maioria dos casos realizado pela necropsia, ou achados durante procedimentos cirúrgicos. O tratamento recomendado é a remoção cirúrgica do nematódeo, em casos diagnosticados precocemente, e em casos tardios, a nefrectomia do rim afetado. O presente trabalho teve como objetivo relatar um caso de dioctofimose em um cão no Município de Valença, RJ, onde foi realizada a nefrectomia do rim afetado, após ter sido diagnosticado a parasitose através de exame ultrassonográfico.
Dewetting experiments on molten spherulites, previously grown at Tc = 120 °C in thin films of isotactic polypropylene (iPP), revealed two kinds of instabilities of the dewetting rims, namely a ...fingering instability and a fracture instability for dewetting temperatures Ts above and below ca. 165 °C, respectively. For Ts ≥ 165 °C, the dynamics of growing dewetting holes on slippery substrates was governed by viscous dissipation, causing undulations leading to a fingering instability of the rims. However, for 160 °C < Ts < 165 °C, the dewetting rims exhibited a fracture instability, which was related to the release of elastic energy stored in the rim. From the dewetting dynamics of the molten polymers, we derived the non-equilibrium viscosity ηnon-equ(Ts) and equilibrated viscosity ηequ(Ts) as a function of Ts. The values of ηnon-equ(Ts) were significantly larger than ηequ(Ts), with differences decreasing for increasing Ts. Interestingly, extrapolation of ηnon-equ(Ts) to the cross-over point ηnon-equ = ηequ yielded Ts,cross ≈ 166 °C. We relate Ts,cross with the maximum melting temperature of crystalline domains which existed within iPP spherulites. Below Ts,cross, not all crystallites were molten and the melt contained crystalline seeds. Above Ts,cross, the melt was homogeneous and free of any seeds. Our approach opens up a new possibility for determining the maximum melting temperature of polymer crystals.
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•The fingering instability and fracture instability were respectively observed in homogeneous melt and heterogeneous melt.•The rim instability changed from fingering to fracture at 165 °C was revealed by dewetting of iPP films.•The non-equilibrium viscosity extrapolated to the equilibrium viscosity at a cross-over temperature Ts,cross ≈ 166 °C.•The Ts,cross was considered as the maximum melting temperature of crystalline domains within iPP spherulites.
B4C‐TiB2 ceramics (TiB2 ranging 5~70 vol%) with Mo‐Co‐WC as the sintering additive were prepared by spark plasma sintering. In comparison with B4C‐TiB2 without additive, the enhanced densification ...was evident in the sintered specimen with Mo‐Co‐WC additive. Core‐rim structured grain was observed around TiB2 grains. The interface of the rim between TiB2 and B4C phases demonstrated different feature: the inner borderline of the rim exhibited a smooth feature, whereas a sharp curved grain boundary was observed between the rim and the B4C grain. The formation mechanism is discussed: the epitaxial growth of (Ti,Mo,W)B2 rim around the TiB2 core may occur as a result of the solid solution and dissolution‐precipitation between TiB2 phase and the sintering additive. It was revealed that the fracture toughness increased as the content of TiB2 content increased, alongside the decreased hardness. B4C‐30 vol% TiB2 specimen demonstrated the optimal combination of mechanical properties, reaching Vickers hardness of 24.3 GPa and fracture toughness of 3.33 MPa·m1/2.
To optimize the inclined rim design, multi-objective optimization was numerically conducted on the suction-side rim of the squealer tip in the GE-E3 rotor blade. The RANS equations, incorporating ...with the standard k-ω model, were numerically solved. Through the implementation of a Kriging surrogate model coupled with the NSGA-II evolutionary optimization technique, six geometric parameters on the suction-side rim went through iterative optimization. This process yielded three optimized squealer tip geometries on the Pareto front: Structure 1 with minimum total pressure loss, Structure 2 with optimal comprehensive aerothermal performance, and Structure 3 with minimum tip heat load. Comparative analysis revealed that with the inner and external wall inclined toward the cavity and passage respectively, the optimization results in a 3 %–11 % reduction in tip heat load, accompanied by an 8.5 %–10.2 % reduction in aerodynamic loss, facilitated by an attenuated upper passage vortex (UPV) and strengthened tip leakage vortex (TLV). The critical inclined region of the external rim wall, spanning 7 %–80 %, influences the exit total pressure loss distribution. The inclined inner wall upstream of 50 % Cax obstructs coolant jets from exiting the cavity, reducing the heat load on the cavity bottom. However, the inclined external wall from 66 % to 90 % Cax amplifies the impingement of the scraping vortex (SV), increasing local heat transfer. The thermal behavior of Structure 1 is sensitive to changes in tip clearance, whereas Structure 2 and 3 show more robust advantages. As the clearance increased, the aerodynamic losses associated with the TLV rise for all three optimized tips, but losses from the UPV remain similar. This study provides a novel approach for designing efficient squealer tip geometries incorporating an inclined rim.
In modern aero-engine, the turbine rim seals whose purpose is to reduce the ingress are located in a complex flow region between the mainstream and secondary air flows. The sealing air discharged ...from the compressor of engine is used to purge turbine cavity. In order to examine the effects of ingress through four distinct rim seals, a one-stage test rig was used in the experiments presented in this work. At a Reynolds number of 5.16 × 105 in the mainstream and (0.85–2.13) × 106 in the rotational, the radial pressure distribution on the stator was determined. To assess flow characteristics and sealing efficacy, measurements of the swirl ratio and CO2 concentration were made. The reliability of turbine rim-seals is determined by the locations of the hook and teeth, as well as their effect on hot gas ingestion. To evaluate the performance of four types of seals: a datum double-rim seal and three derivatives with different clearances, the data are employed. Due to the inlet air position, the swirl ratio exhibited a pronounced inflection for all the rim seals. The sealing efficiency can be decreased by putting the hook closer to the rim or by taking the teeth out. Static pressure measurements in the turbine cavity indicate that the seal position has a significant impact. The analysis results revealed that the existence of slot vortex is beneficial to improving efficiency.
Introduction
Most classification systems for lateral discoid meniscus do not evaluate instability of the meniscal peripheral rim. Considerable variability in the prevalence of peripheral rim ...instability has been published, and it appears that instability is underestimated. The purpose of this study was: first, to evaluate the prevalence of peripheral rim instability and its location in the symptomatic lateral discoid meniscus, and second, to investigate if patient age or type of discoid meniscus are possible risk factors for instability.
Methods
A cohort of 78 knees that underwent operative treatment due to symptomatic discoid lateral meniscus was analyzed retrospectively for the rate and location of peripheral rim instability.
Results
Out of the 78 knees, 57.7% (45) had a complete and 42.3% (33) had an incomplete lateral meniscus. The prevalence of peripheral rim instability in symptomatic lateral discoid menisci was 51.3%, and with 32.5%, the anterior attachment was most commonly affected, followed by the posterior (30%) and central (10%) attachment. 27.5% of the tested menisci were unstable anteriorly and posteriorly. There was no significant difference in the prevalence of rim instability between the type of discoid menisci (complete vs. incomplete), nor was there a significant correlation for age as a risk factor for instability.
Conclusion
The discoid lateral meniscus has a high prevalence and variable location of peripheral rim instability. Meniscal rim stability must be tested and addressed cautiously in all parts and in all types of discoid lateral menisci during operative treatment.
In this paper, multiband antennas based on a single ring slot are proposed for 4G/5G smartphone applications. The basic structure of the antenna is consisted of a large metal ground and an unbroken ...metal rim, in which a single 2 mm-wide ring slots is realized between the metal ground and rim. Here, a reconfigurable 4G antenna (820-960 and 1710-2690 MHz) is initially devised by loading multiple grounded stubs and a simple dc controlling circuit with varactor diode into the upper section of the ring slot. To further cover the sub-6 GHz spectrum (3400-3600 MHz) for future 5G communications, a four-element multi-input multi-output (MIMO) slot antennas configuration is designed by utilizing the lower section of the ring slot. A prototype antenna was fabricated, and good agreement is shown between the measured and simulated results. Due to the advantages such as multiband operation, MIMO configuration for 5G communications, high isolation, and compact structure, the proposed antenna design is attractive for 4G/5G smartphones.
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