Usher syndrome (USH) comprises a group of autosomal recessively inherited disorders characterized by a dual sensory impairment of the audiovestibular and visual systems. Three major clinical subtypes ...(USH type I, USH type II and USH type III) are distinguished on the basis of the severity of the hearing loss, the presence or absence of vestibular dysfunction and the age of onset of retinitis pigmentosa (RP). Since the cloning of the first USH gene (MYO7A) in 1995, there have been remarkable advances in elucidating the genetic basis for this disorder, as evidence for 11 distinct loci have been obtained and genes for 9 of them have been identified. The USH genes encode proteins of different classes and families, including motor proteins, scaffold proteins, cell adhesion molecules and transmembrane receptor proteins. Extensive information has emerged from mouse models and molecular studies regarding pathogenesis of this disorder and the wide phenotypic variation in both audiovestibular and/or visual function. A unifying hypothesis is that the USH proteins are integrated into a protein network that regulates hair bundle morphogenesis in the inner ear. This review addresses genetics and pathological mechanisms of USH. Understanding the molecular basis of phenotypic variation and pathogenesis of USH is important toward discovery of new molecular targets for diagnosis, prevention and treatment of this debilitating disorder.
In this Letter, we present a spectacular eruptive flare (X8.2) associated with a coronal mass ejection on 2017 September 10 at the west limb of the Sun. A flux rope eruption is followed by the ...inflow, the formation of a current sheet, and a cusp structure, which were simultaneously observed during the occurrence of this flare. The hierarchical layers of the cusp-shaped structure are well observed in 131 observation. The scenario that can be created from these observations is very consistent with the predictions of some eruptive models. Except for the characteristics mentioned above in the process of the flare predicted by classical eruption models, the current sheet separating into several small current sheets is also observed at the final stage of the flux rope eruption. The quantitative calculation of the velocities and accelerations of the inflow, hot cusp structure, and post-flare loops is presented. The width of the current sheet is estimated to be about 3 × 103 km. These observations are very useful in understanding the process of solar eruptions.
A three-dimensional coupled hydrodynamic–biogeochemical model with multiple nutrient and plankton functional groups was developed and adapted to the Gulf of Mexico to investigate the role of ...nutrients and the complexity of plankton community in dissolved oxygen (DO) dynamics. A 15-year hindcast was achieved covering the period of 2006–2020. Extensive model validation against in situ data demonstrates that the model was capable of reproducing vertical distributions of DO and spatial distributions of bottom DO concentration, as well as their interannual variations. The study demonstrates that bottom DO dynamics and hypoxia evolution are significantly influenced by both physical processes and local biochemistry, with sedimentary oxygen consumption and vertical diffusion identified as key contributors. Summer hydrodynamics play a critical role in nutrient distribution and limitation: a notable expansion of Si limitation was simulated when coastal currents shifted eastward or northward. This effect, especially pronounced on the western part of the Louisiana–Texas shelf, underscores the importance of nutrient limitation in shaping DO dynamics. The model identifies a bi-peak primary production pattern in spring and early summer, aligned with satellite chlorophyll a variations, attributed to the complexity of the plankton community and interactions among different plankton groups. Our findings emphasize the necessity of integrating sophisticated plankton community dynamics into biogeochemical models to understand primary production variability and its impact on bottom hypoxia.
Reactive crystallization to make cefixime trihydrate crystals via cefixime disodium reacting with hydrogen chloride was investigated using ATR FTIR and an online imaging instrument with the aim of ...developing an improved understanding of the operation and condition optimization and scale-up. The operation involves times of continuing introduction of aqueous HCl solution into a cefixime disodium solution in water and also periods at which HCl was stopped for breeding of crystals. The concentration profile of the reactant cefixime disodium monitored by ATR FTIR being almost constant in the first 30–40 min since the start of introduction of HCl suggests that cefixime disodium (cefixime2–) reacts with HCl to form cefixime sodium (cefixime1–) first, prior to the formation of solids. Online imaging, off-line SEM image analysis, and XRD analysis revealed that spherical amorphous solids were formed first; the solids were then aggregated, followed by phase transition on the surface of aggregates to well-shaped crystals. The causal relationship between the process conditions and the size, impurity content, crystallinity, and whiteness of the cefixime trihydrate crystals was also investigated. It was found that the solution pH value at the time at which introduction of the first portion of HCl solution was stopped to begin breeding crystals has a major impact on both the size and the whiteness of the crystals. High pH value favors smaller crystals with a sharp white appearance. The length of the crystal breeding time was found to be critical to the crystallinity. Explanation of the observed phenomena and an operational envelope were defined. The size distribution, whiteness, impurity content, and crystallinity of cefixime trihydrate crystals were satisfactory as long as the operation was kept within the defined envelope. The experiments were conducted on a 2 L reactor, then successfully scaled-up to 50 and 4000 L in industry after having considered the scale-up factor in stirrer rotation speed.
► IL-based, Li/LiFePO
4 and Li
4Ti
5O
12/LiFePO
4 stacked prototypes were fabricated. ► Above 80% of the initial capacity is delivered after 800 cycles with an efficiency of 100%. ► The ...reproducibility of the manufacturing process was validated.
The lab-scale manufacturing of Li/LiFePO
4 and Li
4Ti
5O
12/LiFePO
4 stacked battery prototypes and their performance characterization are described here. The prototypes were realized in the frame of an European Project devoted to the development of greener and safer lithium batteries, based on ionic liquid electrolytes, for integration with photovoltaic panels.
N-Butyl-
N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR
14TFSI) and
N-butyl-
N-methylpyrrolidinium bis(fluoro-methanesulfonyl)imide (PYR
14FSI), selected as the ionic liquids (ILs), were used to formulate the poly(ethylene oxide)-LiN(SO
2CF
3)
2-PYR
14TFSI (PEO-LiTFSI-PYR
14TFSI) polymer electrolyte and the LiTFSI-PYR
14FSI liquid electrolyte, which were employed to produce lithium metal and lithium-ion prototypes, respectively. The composite electrodes for the lithium metal and lithium-ion prototypes were prepared through, respectively, a solvent-free and a water-based procedure route. The performance of the lithium battery prototypes was evaluated in terms of specific capacity, energy, cycle life and coulombic efficiency at different current densities. The results have indicated high reproducibility and the feasibility of scaling-up solvent-free, lithium batteries based on ionic liquids for low and mid rate applications such as renewable energy storage.
Considering the carbon nanotubes’ (CNTs) orientation distribution a new model of effective thermal conductivity of CNTs-based composites is presented. Based on Maxwell theory, the formulae of ...calculating effective thermal conductivity of CNTs-based composites are given. The theoretical results on the effective thermal conductivity of CNTs/oil and CNTs/decene suspensions are in good agreement with the experimental data. The model is valid for the transport properties of the CNTs-based composites.
A hallmark of mitosis is the appearance of high levels of histone phosphorylation, yet the roles of these modifications remain largely unknown. Here, we demonstrate that histone H3 phosphorylated at ...threonine 3 is directly recognized by an evolutionarily conserved binding pocket in the BIR domain of Survivin, which is a member of the chromosomal passenger complex (CPC). This binding mediates recruitment of the CPC to chromosomes and the resulting activation of its kinase subunit Aurora B. Consistently, modulation of the kinase activity of Haspin, which phosphorylates H3T3, leads to defects in the Aurora B-dependent processes of spindle assembly and inhibition of nuclear reformation. These findings establish a direct cellular role for mitotic histone H3T3 phosphorylation, which is read and translated by the CPC to ensure accurate cell division.
Comparison of image processing techniques is critically important in deciding which algorithm, method, or metric to use for enhanced image assessment. Image fusion is a popular choice for various ...image enhancement applications such as overlay of two image products, refinement of image resolutions for alignment, and image combination for feature extraction and target recognition. Since image fusion is used in many geospatial and night vision applications, it is important to understand these techniques and provide a comparative study of the methods. In this paper, we conduct a comparative study on 12 selected image fusion metrics over six multiresolution image fusion algorithms for two different fusion schemes and input images with distortion. The analysis can be applied to different image combination algorithms, image processing methods, and over a different choice of metrics that are of use to an image processing expert. The paper relates the results to an image quality measurement based on power spectrum and correlation analysis and serves as a summary of many contemporary techniques for objective assessment of image fusion algorithms.
Quantum computation attaches importance to high-precision quantum manipulation, where the quantum state transfer with high fidelity is necessary. Here, we propose a new scheme to implement the ...quantum state transfer of high fidelity and long distance, by adding on-site potential into the qubit chain and enlarging the proportion of the coupling strength between the two ends and the chain. In the numerical simulation, without decoherence, the transfer fidelities of 9 and 11 qubit chain are 0.999 and 0.997, respectively. Moreover, we give a detailed physical realization scheme of the quantum state transfer in superconducting circuits, and discuss the tolerance of our proposal against decoherence. Therefore, our scheme will shed light on quantum computation with long chain and high-fidelity quantum state transfer.
A solar cell based on the n-MoS
2
/i-SiO
2
/p-Si heterojunction is fabricated. The device exhibits a high power-conversion efficiency of 4.5% due to the incorporation of a nano-scale SiO
2
buffer ...into the MoS
2
/Si interface. The present device architectures are envisaged as potentially valuable candidates for high-performance photovoltaic devices.
A solar cell based on the n-MoS
2
/i-SiO
2
/p-Si heterojunction is fabricated.
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