In recent years, the rapid urbanization of world's population causes many economic, social, and environmental problems, which affect people's living conditions and quality of life significantly. The ...concept of "smart city" brings opportunities to solve these urban problems. The objectives of smart cities are to make the best use of public resources, provide high-quality services to the citizens, and improve the people's quality of life. Information and communication technology plays an important role in the implementation of smart cities. Blockchain as an emerging technology has many good features, such as trust-free, transparency, pseudonymity, democracy, automation, decentralization, and security. These features of blockchain are helpful to improve smart city services and promote the development of smart cities. In this paper, we provide a comprehensive survey on the literature involving blockchain technology applied to smart cities. First, the related works and background knowledge are introduced. Then, we review how blockchain technology is applied in the realm of smart cities, from the perspectives of smart citizen, smart healthcare, smart grid, smart transportation, supply chain management, and others. Finally, some challenges and broader perspectives are discussed.
Chemical and mechanical properties of lithology exert a first‐order control on landscape evolution and biological colonization of substrate. To quantify the influence of lithology on topography, ...vegetation density, and animal biodiversity, I compile lithologic, topographic, climatic, and biological data sets for mountainous regions globally. I find significant variations in the topographic steepness of regions underlain by different lithologies that, accounting for tectonic uplift, likely reflect lithologic differences in erosional resistance. These relative differences in erodibility are similar across different climate zones. To isolate the effect of lithology on vegetation and animal biodiversity, I account for the heterogeneous lithologic distribution among climate zones. I show that siliciclastic, plutonic, and, for some biological variables, metamorphic rocks exhibit elevated values of Normalized Difference Vegetation Index and tetrapod and amphibian species richness relative to carbonate rocks. These results likely reflect lithology‐related variation in soil nutrients and hydrology that promote or inhibit habitat suitability.
Plain Language Summary
A myriad of rock types are exposed at Earth's surface, all of which have different chemical and physical properties. These differences are important because rock properties affect processes on Earth's surface that shape topography and because rocks are the base material from which most soils form. Here, I investigate how the steepness of a landscape varies based on differences in rock type and show that rock type variations can partly explain Earth's topography. I also test whether the differences in rock type that lead to variations in soil properties and water availability influence plant cover and animal richness globally. I find that limestone areas have less vegetation and lower numbers of amphibian, bird, and mammalian species. This is likely related to low water availability and nutrient content in limestone areas.
Key Points
Erodibility differences between lithologies partially control mountainous topography globally
Vegetation density and biodiversity are globally affected by variations in lithology
Hydrologic and chemical properties of carbonates have a negative effect on vegetation density and animal biodiversity
To study the structural and angiographic optical coherence tomography (OCT) data of the macula from controls, patients with diabetes, and patients with glaucoma to evaluate neurovascular and ...structural relationships.
This was a retrospective study of 89 eyes from 49 patients in a community-based retinal referral practice with diabetes, glaucoma, and normal controls. The patients were evaluated with OCT to include retinal nerve fiber layer (RNFL) thickness measurement and ganglion cell layer (GCL) volume determination. The vascular density of the radial peripapillary capillary network and the vascular plexuses in the macula were evaluated with OCT angiography. The main outcome measures were the data obtained per disease state and the interrelationships the data displayed.
The mean GCL volumes were significantly lower than the control group in both the diabetic (P = .016) and glaucoma (P < .001) groups. The difference between the diabetic and glaucoma groups was not significant (P = .052). The mean global vascular density was greater in the control group than the diabetic group (P = .002) and the glaucoma group (P < .001). The mean RNFL thicknesses were lowest in the glaucoma group. Both the diabetic and glaucoma groups had significantly lower radial peripapillary network and deep vascular plexus density values compared to controls.
Although there are important differences in disease pathogenesis between diabetes and glaucoma, they share certain similarities in the structural and angiographic abnormalities eventually produced. This suggests that, in addition to canonical pathways of disease, a component of both could represent neurodegenerative disease, offering the possibility for the development of new treatments. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.
Aging is a primary risk factor for the development of osteoarthritis and the understanding of how aging processes contribute to the development of osteoarthritis is an important area of active ...research. The most recent literature in this area was reviewed in order to update investigators on the status of the field.
The field is beginning to move beyond a cartilage focus to include other joint tissues relevant to osteoarthritis such as ligaments, meniscus, and bone. Synovitis also appears to play a role in osteoarthritis but has not been a focus of aging studies. Studies in small animals, including mice and rats, demonstrate age-related changes that can contribute to osteoarthritis and show that animal age is a key factor to be considered in interpreting the results of studies using surgically induced models of osteoarthritis. There is accumulating evidence that cellular processes such as damage-induced cell senescence contribute to osteoarthritis and a growing body of literature on the role of epigenetic regulation of gene expression in aging and osteoarthritis.
Not all osteoarthritis is due to aging processes in joint tissues, but the age-related changes being discovered certainly could play a major contributing role.
Mastering dynamic free-space spectral control and modulation in the near-infrared (NIR) and optical regimes remains a challenging task that is hindered by the available functional materials at high ...frequencies. In this work, we have realized an efficient metadevice capable of spectral control by minimizing the thermal mass of a vanadium dioxide phase-change material (PCM) and placing the PCM at the feed gap of a bow-tie field antenna. The device has an experimentally measured tuning range of up to 360 nm in the NIR and a modulation depth of 33% at the resonant wavelength. The metadevice is configured for integrated and local heating, leading to faster switching and more precise spatial control compared with devices based on phase-change thin films. We envisage that the combined advantages of this device will open new opportunities for signal processing, memory, security, and holography at optical frequencies.
The lightest hidden-bottom tetraquarks in the dynamical diquark model fill an S -wave multiplet consisting of 12 isomultiplets. We predict their masses and dominant bottomonium decay channels using a ...simple three-parameter Hamiltonian that captures the core fine-structure features of the model, including isospin dependence. The only experimental inputs needed are the corresponding observables for Zb ( 10610 ) and Zb ( 10650 ). The mass of Xb, the bottom analogue to X ( 3872 ), is highly constrained in this scheme. In addition, using lattice-calculated potentials we predict the location of the center of mass of the P -wave multiplet and find that Y ( 10860 ) fits well but the newly discovered Y ( 10750 ) does not, more plausibly being a D -wave bottomonium state. Using similar methods, we also examine the lowest S-wave multiplet of six cc ss states, assuming as in earlier work that X ( 3915 ) and Y ( 4140 ) are members, and predict the masses and dominant charmonium decay modes of the other states. We again use lattice potentials to compute the centers of mass of higher multiplets and find them to be compatible with the masses of Y ( 4626 ) ( 1 P ) and X ( 4700 ) ( 2 S ), respectively.
To investigate the long-term clinical course of eyes with pseudodrusen appearance caused by subretinal drusenoid deposits.
Eyes from the original study identifying subretinal deposits of material as ...the cause of pseudodrusen appearance were evaluated in a retrospective study of outer retinal morphology. The distance between the inner plexiform layer and the retinal pigment epithelium, termed the photoreceptor length, was measured from optical coherence tomography approximately 2 mm superior to the fovea at baseline and at follow-up visits. The choroidal thickness was measured directly under this retinal area.
Of the 21 eyes available for follow-up, 9 (42.9%) eventually developed choroidal neovascularization over a mean 2.9-year follow-up period. Regression of subretinal drusenoid deposits was seen in 9 eyes (42.9%) as well. Those with regression of subretinal drusenoid deposits had a decrease in the photoreceptor length with the final photoreceptor length being 74.4% of the initial length (P < 0.001). In eyes with regression, the underlying choroid was 81.4% of its initial value (P = 0.01) at the final follow-up. Eyes with regression also showed loss of the ellipsoid band. Eyes without regression had no change in photoreceptor length, choroidal thickness, or outer retinal architecture.
Eyes with regression of subretinal drusenoid deposits develop outer retinal atrophy and loss of the underlying choroidal thickness. This finding seems common in eyes having pseudodrusen and represents a late form of age-related macular degeneration that is not in current classification systems. Further study is needed to determine both the true prevalence and the effects on visual function.
Abstract
Merons are nontrivial topological spin textures highly relevant for many phenomena in solid state physics. Despite their importance, direct observation of such vortex quasiparticles is ...scarce and has been limited to a few complex materials. Here, we show the emergence of merons and antimerons in recently discovered two-dimensional (2D) CrCl
3
at zero magnetic field. We show their entire evolution from pair creation, their diffusion over metastable domain walls, and collision leading to large magnetic monodomains. Both quasiparticles are stabilized spontaneously during cooling at regions where in-plane magnetic frustration takes place. Their dynamics is determined by the interplay between the strong in-plane dipolar interactions and the weak out-of-plane magnetic anisotropy stabilising a vortex core within a radius of 8–10 nm. Our results push the boundary to what is currently known about non-trivial spin structures in 2D magnets and open exciting opportunities to control magnetic domains via topological quasiparticles.
Background: Both performance‐based and rating measures are commonly used to index executive function in clinical and neuropsychological assessments. They are intended to index the same broad ...underlying mental construct of executive function. The association between these two types of measures was investigated in the current article.
Method and Results: We examined the association between performance‐based and rating measures of executive function in 20 studies. These studies included 13 child and 7 adult samples, which were derived from 7 clinical, 2 nonclinical, and 11 combined clinical and nonclinical samples. Only 68 (24%) of the 286 relevant correlations reported in these studies were statistically significant, and the overall median correlation was only .19.
Conclusions: It was concluded that performance‐based and rating measures of executive function assess different underlying mental constructs. We discuss how these two types of measures appear to capture different levels of cognition, namely, the efficiency of cognitive abilities and success in goal pursuit. Clinical implications of using performance‐based and rating measures of executive function are discussed, including the use of these measures in assessing ADHD.
Airway smooth muscle pathophysiology in asthma Camoretti-Mercado, Blanca; Lockey, Richard F.
Journal of allergy and clinical immunology,
06/2021, Letnik:
147, Številka:
6
Journal Article
Recenzirano
The airway smooth muscle (ASM) cell plays a central role in the pathogenesis of asthma and constitutes an important target for treatment. These cells control muscle tone and thus regulate the opening ...of the airway lumen and air passage. Evidence indicates that ASM cells participate in the airway hyperresponsiveness as well as the inflammatory and remodeling processes observed in asthmatic subjects. Therapeutic approaches require a comprehensive understanding of the structure and function of the ASM in both the normal and disease states. This review updates current knowledge about ASM and its effects on airway narrowing, remodeling, and inflammation in asthma.
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