Topological Factoring of Zero Dimensional Dynamical Systems

We prove that every topological factoring between two zero dimensional dynamical systems can be modelled by a sequence of morphisms (called ordered premorphism) between the levels of the associated Bratteli diagrams. In this way, we also obtain an alternative proof for the theorem proved by T. Shimomura, saying that the realization of a zero dimensional dynamical system $(X,T)$ by a Vershik map on an ordered Bratteli diagram that the set of its maximal paths is associated with a closed subset $W\subseteq X$, is equivalent to have $W$ as a quasi-section. On the other direction, we will prove that given an ordered Bratteli diagram $B$ with a continuous Vershik map on it, every sequence of morphisms between levels of $B$ and $C$, where $C$ is another ordered Bratteli diagram with continuous Vershik map, induces a topological factoring if and only if $B$ has a unique infinite min path. We present a method to construct various examples of premorphisms between two decisive Bratteli diagrams such that the induced maps between the two Vershik systems are not topological factorings.Comment: 40 page

Droplet impact and penetration on series of parallel tubes

Impact and penetration of a liquid droplet on a substrate having a line of parallel capillary openings drilled along its thickness is experimentally studies. Different regimes of droplet penetration are identified. At low impact velocities, the droplet impacts on the substrate, spreads, and penetrates into the substrate mainly due to the capillary action in each tubular hole. At higher impact velocities, the droplet impacts on the substrate, spreads and penetrates due to the droplet inertia, and then penetrates further due to the capillary action. Threshold velocities for liquid penetration into capillary tubes are identified. Two penetration regimes, capillary and inertia driven regimes, have been studied extensively for a range of parameters related to droplet impact on a line of parallel capillary openings. Index Terms—Droplet impact, parallel capillary tubes, penetration, liquid spread

Semi-supervised learning with natural language processing for right ventricle classification in echocardiography - a scalable approach

We created a deep learning model, trained on text classified by natural language processing (NLP), to assess right ventricular (RV) size and function from echocardiographic images. We included 12,684 examinations with corresponding written reports for text classification. After manual annotation of 1489 reports, we trained an NLP model to classify the remaining 10,651 reports. A view classifier was developed to select the 4-chamber or RV-focused view from an echocardiographic examination (n\ua0=\ua0539). The final models were two image classification models trained on the predicted labels from the combined manual annotation and NLP models and the corresponding echocardiographic view to assess RV function (training set\ua0n\ua0=\ua011,008) and size (training set\ua0n\ua0=\ua09951. The text classifier identified impaired RV function with 99% sensitivity and 98% specificity and RV enlargement with 98% sensitivity and 98% specificity. The view classification model identified the 4-chamber view with 92% accuracy and the RV-focused view with 73% accuracy. The image classification models identified impaired RV function with 93% sensitivity and 72% specificity and an enlarged RV with 80% sensitivity and 85% specificity; agreement with the written reports was substantial (both κ\ua0=\ua00.65). Our findings show that models for automatic image assessment can be trained to classify RV size and function by using model-annotated data from written echocardiography reports. This pipeline for auto-annotation of the echocardiographic images, using a NLP model with medical reports as input, can be used to train an image-assessment model without manual annotation of images and enables fast and inexpensive expansion of the training dataset when needed

SOX2 and Bcl-2 as a Novel Prognostic Value in Hepatocellular Carcinoma Progression

Sex-determining region Y-box 2 (SOX2) is a stem cell transcription factor and a major regulator of self-renewal and pluripotency of cancer stem cells (CSCs). In many types of cancer, SOX2 is dysregulated due to overexpression associated with tumor progression and low survival rate. Many HCC cases encounter recurrence and metastasis which might be due to CSCs and also apoptosis. Since little is known about the expression pattern of SOX2 and apoptotic genes in HCC, we aimed to determine the prognostic significance of SOX2, Bax, and Bcl-2 in clinicopathological features, tumor progression, and survival rate of the HCC patients. The expression of SOX2, Bax, and Bcl-2 were evaluated using qRT-PCR in 53 formalin-fixed, paraffin-embedded tissues (FFPE) of patients and 44 controls. Correlation of these genes was analyzed with clinicopathological features and tumor progression. The correlationship between SOX2 expression and ALBI grade as prognostic indicators were calculated. Survival rates were determined by Kaplan–Meier survival curves. SOX2 and Bcl-2 were remarkably overexpressed in HCC patients compared to controls (p = 0.04 and p = 0.003, respectively). A significant association was found for both SOX2 and Bcl-2 overexpression with TNM staging (p = 0.02, p = 0.04) and tumor grading (p = 0.01, p = 0.003), respectively. A significant correlation was observed: patients with SOX2 overexpression had a lower 5-year overall survival rate (p = 0.04); however, there was no significant association between Bcl-2 and survival (p = 0.5). Collectively, overexpression of SOX2 and Bcl-2, alone or combined, may be a potential marker to evaluate prognosis and response to HCC treatment

Defining microRNA signatures of hair follicular stem and progenitor cells in healthy and androgenic alopecia patients

[Background]: The exact pathogenic mechanism causes hair miniaturization during androgenic alopecia (AGA) has not been delineated. Recent evidence has shown a role for non-coding regulatory RNAs, such as microRNAs (miRNAs), in skin and hair disease. There is no reported information about the role of miRNAs in hair epithelial cells of AGA.[Objectives]: To investigate the roles of miRNAs affecting AGA in normal and patient’s epithelial hair cells.[Methods]: Normal follicular stem and progenitor cells, as well as follicular patient’s stem cells, were sorted from hair follicles, and a miRNA q-PCR profiling to compare the expression of 748 miRNA (miRs) in sorted cells were performed. Further, we examined the putative functional implication of the most differentially regulated miRNA (miR-324-3p) in differentiation, proliferation and migration of cultured keratinocytes by qRT-PCR, immunofluorescence, and scratch assay. To explore the mechanisms underlying the effects of miR-324-3p, we used specific chemical inhibitors targeting pathways influenced by miR-324-3p.[Result]: We provide a comprehensive assessment of the "miRNome" of normal and AGA follicular stem and progenitor cells. Differentially regulated miRNA signatures highlight several miRNA candidates including miRNA-324-3p as mis regulated in patient’s stem cells. We find that miR-324-3p promotes differentiation and migration of cultured keratinocytes likely through the regulation of mitogen-activated protein kinase (MAPK) and transforming growth factor (TGF)-β signaling. Importantly, pharmacological inhibition of the TGF-β signaling pathway using Alk5i promotes hair shaft elongation in an organ-culture system.[Conclusion]: Together, we offer a platform for understanding miRNA dynamic regulation in follicular stem and progenitor cells in baldness and highlight miR-324-3p as a promising target for its treatment.This study was funded by a grant provided from Royan Institute and Disease Models & Mechanisms Travelling Fellowship by Biologists Company.Peer reviewe

Feasibility of shape memory alloy in a tuneable mass damper to reduce excessive in-service vibration

The applications of shape memory alloy (SMA) in vibration reduction are benefited by its superelasticity and thermomechanical properties. This study is a part of a series of research projects focused on reduction of timber floor vibration. In this study, the feasibility of this tuneable mass damper is tested for in-service vibration reduction. At first, the effect of temperature ranging from 11 °C to 120 °C on the dynamic characteristics of SMA was investigated under different pre-stressed levels. At higher temperatures, the damping ratio reduces while stiffness increases, and vice versa with decreasing temperature. SMA is sensitive to temperature when the pre-stressed level is near the phase transformation stress. Next, the analytical model of timber floor system was built and idealised as a two-degree-of-freedom system. Thirdly, a series of lab tests were carried out, and a damper consisting of an SMA bar was added on a cantilever beam with different natural frequencies, which represents floor system in the model. The results show that the vibration response of the system can be significantly reduced by the damper developed in this project, when the damper has resonance with the system. The mass of the system was then changed so as to make the damper out-of-tuned; the damper was then retuned by cooling/heating on SMA. After retuning of the damper, the response of the system was effectively reduced, which demonstrates the effectiveness and feasibility of employing SMA in the damper system

On the Precision Grip in Manual Transport

The aim of the present study was to investigate the grip and load force relations in the precision grip (between thumb and index finger) in static and dynamic situations, and to develop automatic procedures for the analysis of position and force data from tests involving the precision grip. The goal of the work was to create physiologically based methods for identification and quantitative determination of disturbances in the nervous control of hand motor function. In the static case, the excess grip force used in order to maintain a certain safety margin, lifting a 600 g object using the precision grip, was explored. Special algorithms were developed to automatically determine this safety margin. In the dynamic case, the grip-lift synergy was investigated using a manual transport task. Algorithms were developed to determine and analyze the different phases of the transport. The effect of movement speed on the manual transport task was investigated. Special parameters were defined to examine the significance of this effect. The static and dynamic precision grip methods were used on patients with movement disorders as well as on healthy persons. A safety margin analysis was performed in Rheumatoid Arthritis patients and in healthy persons. Differences were found in motor behavior between the two groups but no correlation was found for the safety margin and a simple timed test (GAT). The correlation coefficient between GF and LF was determined in manual transport phases in movements both in the forward and the backward direction. Parkinson patients in medicated and non-medicated state as well as healthy persons participated. There were higher correlation coefficients between the grip and load forces in the initial phases, before the lift was completely established, as compared to the ballistic phases of the transport. This was evident both in PD patients and healthy persons. Precision grip parameters were calculated for healthy subjects. All of the parameters had a significant relation to the movement speed, which indicates that movement speed can be a regulatory variable for the generation of the grip and load forces. Force-movement analysis is well suited for the study of hand motor function. Dividing the task into appropriate phases opens possibilities to select specific indicators for different CNS disturbances