Abstract
Phase-contrast in tapping-mode atomic force microscopy (TM-AFM) results from dynamic tip-surface interaction losses which allow soft and hard nanoscale features to be distinguished. So far, ...phase-contrast in TM-AFM has been interpreted using homogeneous Boltzmann-like loss distributions that ignore fluctuations. Here, we revisit the origin of phase-contrast in TM-AFM by considering the role of fluctuation-driven transitions and heterogeneous loss. At ultra-light tapping amplitudes <3 nm, a unique amplitude dependent two-stage distribution response is revealed, alluding to metastable viscous relaxations that originate from tapping-induced surface perturbations. The elastic and viscous coefficients are also quantitatively estimated from the resulting strain rate at the fixed tapping frequency. The transitional heterogeneous losses emerge as the dominant loss mechanism outweighing homogeneous losses at smaller amplitudes for a soft-material. Analogous fluctuation mediated phase-contrast is also apparent in contact resonance enhanced AFM-IR (infrared), showing promise in decoupling competing thermal loss mechanisms via radiative and non-radiative pathways. Understanding the loss pathways can provide insights on the bio-physical origins of heterogeneities in soft-bio-matter e.g., single cancer cell, tumors, and soft-tissues.
Despite accumulating evidence indicating a key role of interferon-γ (IFN-γ)-producing immune cells in ocular infection and immunity, little is known about the direct effects of IFN-γ on resident ...corneal cells or on the ocular surface. Here, we report that IFN-γ impacts corneal stromal fibroblasts and epithelial cells to promote inflammation, opacification, and barrier disruption on the ocular surface, leading to dry eye. Our results demonstrated that IFN-γ dose-dependently induced cytotoxicity, pro-inflammatory cytokine/chemokine production, and expression of major histocompatibility complex class II and CD40 in cultures of corneal stromal fibroblasts and epithelial cells while increasing myofibroblast differentiation of corneal stromal fibroblasts. In mice, subconjunctival IFN-γ administration caused corneal epithelial defects and stromal opacity in dose- and time-dependent manners while promoting neutrophil infiltration and inflammatory cytokine expression in the cornea. Moreover, IFN-γ reduced aqueous tear secretion and the number of conjunctival goblet cells responsible for mucinous tear production. Together, our findings suggest that IFN-γ induces the ocular surface changes characteristic of dry eye disease at least in part through its direct effects on resident corneal cells.
The use of a balloon guide catheter (BGC) in the endovascular management of acute ischemic stroke is known to improve the efficacy and efficiency of the procedure by reducing the risk of distal ...embolization. During the procedure, the balloon of the catheter causes a temporary arrest of cerebral blood flow. However, failure of the balloon to deflate during the BGC procedure can result in catastrophic complications, including aggravated hypoxic damage. This paper aims to share the resolution and methodological analysis of our experience with BGC balloon deflation failure, which was confirmed by a reproducible experiment under similar conditions.
Humans have suffered from a variety of infectious diseases since a long time ago, and now a new infectious disease called COVID-19 is prevalent worldwide. The ongoing COVID-19 pandemic has led to ...research of the effective methods of diagnosing respiratory infectious diseases, which are important to reduce infection rate and help the spread of diseases be controlled. The onset of COVID-19 has led to the further development of existing diagnostic methods such as polymerase chain reaction, reverse transcription polymerase chain reaction, and loop-mediated isothermal amplification. Furthermore, this has contributed to the further development of micro/nanotechnology-based diagnostic methods, which have advantages of high-throughput testing, effectiveness in terms of cost and space, and portability compared to conventional diagnosis methods. Micro/nanotechnology-based diagnostic methods can be largely classified into (1) nanomaterials-based, (2) micromaterials-based, and (3) micro/nanodevice-based. This review paper describes how micro/nanotechnologies have been exploited to diagnose respiratory infectious diseases in each section. The research and development of micro/nanotechnology-based diagnostics should be further explored and advanced as new infectious diseases continue to emerge. Only a handful of micro/nanotechnology-based diagnostic methods has been commercialized so far and there still are opportunities to explore.
The increasing movement of exotic pathogens calls for systematic surveillance so that newly introduced pathogens can be recognized and dealt with early. A resource crucial for recognizing such ...pathogens is knowledge about the spatial and temporal diversity of endemic pathogens. Here, we report an effort to build this resource for Pennsylvania (PA) by characterizing the identity and distribution of Phytophthora species isolated from diverse plant species in PA nurseries and greenhouses. We identified 1137 Phytophthora isolates cultured from clinical samples of >150 plant species submitted to the PA Department of Agriculture for diagnosis from 1975 to 2019 using sequences of one or more loci and morphological characteristics. The three most commonly received plants were Abies, Rhododendron, and Pseudotsuga. Thirty-six Phytophthora species identified represent all clades, except 3 and 10, and included a distinct subgroup of a known species and a prospective new species. Prominent pathogenic species such as P. cactorum, P. cinnamomi, P. nicotianae, P. drechsleri, P. pini, P. plurivora, and P. sp. kelmania have been found consistently since 1975. One isolate cultured from Juniperus horizontalis roots did not correspond to any known species, and several other isolates also show considerable genetic variation from any authentic species or isolate. Some species were isolated from never-before-documented plants, suggesting that their host range is larger than previously thought. This survey only provides a coarse picture of historical patterns of Phytophthora encounters in PA nurseries and greenhouses because the isolation of Phytophthora was not designed for a systematic survey. However, its extensive temporal and plant coverage offers a unique insight into the association of Phytophthora with diverse plants in nurseries and greenhouses.
We propose a new low-diameter interconnection network called FleX, which offers high flexibility when installing interconnections in a HPC system. FleX consists of multiple layers with only ...connections between neighboring layers and not within each layer. These structural properties make it easy to achieve a low diameter with regardless of the scale. The cross-like connections between the adjacent layers in FleX impart various alternative minimal paths, allowing FleX to have high resiliency and a wide bisection width. We also discuss the minimal routing scheme and a stochastic load balancing scheme (LBR) for the proposed interconnection network. Through cycle-based simulations, the performance of FleX is evaluated, and the cost and power consumption analyses in comparison with other interconnection networks are also conducted. We verify that FleX has high configuration flexibility with regard to cost and performance, and also provides low latency and high saturation throughput with the same cost over the legacy interconnection networks for the HPC system. Moreover, being synergied with the proposing LBR, we also verify that FleX can expand its saturation throughput further while only sacrificing the latency slightly.
A deep learning (DL)‐based approach for analysis is proposed. Using synthetic XRD data for a DL approach is inevitable due to the lack of real‐world XRD data. There are two main challenges when ...conducting a DL‐based XRD analysis: generating realistic XRD data including all possible perturbations, such as peak shift, broadening, texture, and noisy background, and generalizing the DL model applicability to all ICSD entries. To address both the perturbation and generalizability issues, a large‐scale computation is required because it would be infeasible with typical lab‐scale computation. Cloud computing infrastructures are leveraged for parallel computations and to obtain symmetry classification test accuracies of 98.95%, 97.18%, and 96.03% for the crystal system, extinction group, and space group, respectively. A stricter individual compound‐based train and test dataset‐splitting scheme also produces reasonable test accuracies of 92.25%, 87.34%, and 84.39%, which are still state‐of‐the‐art records. Crucially, the DL model trained on synthetic data is assessed using real‐world experimental XRD datasets to ensure its practical applicability. When tested on the real‐world experimental XRD dataset, the model achieves a test accuracy of 90.38% in predicting crystal systems.
Purpose To evaluate the effects of a senofilcon A mechanical protector against corneal endothelial cell damage induced by phacoemulsification in rabbit eyes. Setting Department of Ophthalmology, ...Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul, South Korea. Design Experimental study. Methods The endothelial cell count, intraocular pressure (IOP), and central corneal thickness (CCT) were measured before and 3 days after the experiment in 26 rabbit eyes randomized into a test group and control group (6 per group). In study 1, a senofilcon A mechanical protector was inserted into the anterior chamber in the hard-shell group (test group) whereas, an ophthalmic viscosurgical device (OVD) was injected in the cohesive group (control group). Phacoemulsification was performed for a total of 5 minutes (10-second intervals). In study 2, the soft-shell technique was used in the control group with 5 minutes of continuous phacoemulsification. In 2 eyes, the safety and toxicity of the mechanical protector were evaluated. Results In study 1, there was a 4% loss of endothelial cells associated with the mechanical protector and an 18% loss after phacoemulsification in eyes injected with an OVD; the difference between them was not statistically significant ( P = .394). The IOP and CCT also showed nonsignificant differences in both studies. In study 2, the hard-shell technique induced significantly less endothelial cell damage than the soft-shell group ( P = .026). Endothelial cell loss caused by the mechanical protector was negligible. Conclusion The senofilcon A mechanical protector had a protective effect against corneal endothelial cell damage during phacoemulsification in rabbits.
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