12 research outputs found
Maximum Wireless Power Transmission Using Real-Time Single Iteration Adaptive Impedance Matching
Wireless power transfer (WPT) systems’ efficiency is significantly impacted by non-monotonic variations in the coupling coefficient. For very short distances or strong-coupling cases, the WPT efficiency is minimal at the natural resonant frequency, with two peaks around this frequency, known as the frequency splitting phenomenon. On the other hand, WPT capability decreases for long distances or weak coupling cases. Therefore, adaptive matching is required for WPT systems with varying distances, like wireless charging systems for electric vehicles (EVs). This paper first presents a detailed analysis of the frequency splitting phenomenon by studying the root locations of the WPT system’s transfer function. Then, a real-time fixed-frequency adaptive impedance matching (IM) method is proposed, in which the amplitude and phase of the input impedance is estimated using the average active power, the average reactive power, and the amplitude of input voltage. Unlike traditional search-and-find techniques, the proposed method calculates the optimal IM network parameters only in a single iteration, which improves the convergent speed. A scaled-down 20-Watt prototype controlled by the TMSF2812 is fabricated and used to validate the effectiveness of the proposed method over a wide range of coil-to-coil distances
Transcriptional drug repositioning and cheminformatics approach for differentiation therapy of leukaemia cells.
Differentiation therapy is attracting increasing interest in cancer as it can be more specific than conventional chemotherapy approaches, and it has offered new treatment options for some cancer types, such as treating acute promyelocytic leukaemia (APL) by retinoic acid. However, there is a pressing need to identify additional molecules which act in this way, both in leukaemia and other cancer types. In this work, we hence developed a novel transcriptional drug repositioning approach, based on both bioinformatics and cheminformatics components, that enables selecting such compounds in a more informed manner. We have validated the approach for leukaemia cells, and retrospectively retinoic acid was successfully identified using our method. Prospectively, the anti-parasitic compound fenbendazole was tested in leukaemia cells, and we were able to show that it can induce the differentiation of leukaemia cells to granulocytes in low concentrations of 0.1 μM and within as short a time period as 3 days. This work hence provides a systematic and validated approach for identifying small molecules for differentiation therapy in cancer
The knowledge map of energy security
Much efforts have been made in the area of energy security in recent years, but due to its wide scope, it is necessary to review relevant knowledge activities and to analyze the state of knowledge of the field of energy security measurement. The purpose of this article is to present a comprehensive map of knowledge in the field of energy security. For this reason, many documents and articles have been collected during the period 2002–2019 using 7 large and reputable scientific databases as well as 53 different journals, 90% white Q1 quality. There is employed meta-synthesis, scientometrics and network analysis. In the initial survey stage where 1290 articles were found, after analyzing the content using meta-synthesis, 240 scientific articles related to energy security were identified. Then, the following 14 key questions were addressed such as the main conceptual models, processes, and concept structures (concept map). The VOSviewer and Gephi software are also used to explain the conceptual structure (concept map), hot map, co-occurrence map between keywords and their categorization. After Energy Security (and its subsets), the issues of Renewable Energy Security and Energy Supply Security stand in top ranks. The most cited article in this area is the 2006 “Ensuring energy security” article by Yergin on Energy Security. As many as 58 people have published at least two articles, Sovacool with fifteen articles is on the top author with the most published articles in this field. During the evaluation of the articles, 34 conceptual models and 104 quantitative and qualitative methods were found, which illustrate the wide scope of energy security. By examining the coherent vocabulary map in the field of energy security, it can be said that the most important dimensions of energy security include technology, trade, acceptability, productivity, diversity, equity, availability, governance and efficiency
The potential application of organoids in breast cancer research and treatment
Tumor heterogeneity is a major challenge for breast cancer researchers who have struggled to find effective treatments despite recent advances in oncology. Although the use of 2D cell culture methods in breast cancer research has been effective, it cannot model the heterogeneity of breast cancer as found within the body. The development of 3D culture of tumor cells and breast cancer organoids has provided a new approach in breast cancer research, allowing the identification of biomarkers, study of the interaction of tumor cells with the microenvironment, and for drug screening and discovery. In addition, the possibility of gene editing in organoids, especially using the CRISPR/Cas9 system, is convenient, and has allowed a more detailed study of tumor behavior in models closer to the physiological condition. The present review covers the application of organoids in breast cancer research. The recent use of gene-editing systems to provide insights into therapeutic approaches for breast cancer, is highlighted. The study of organoids and the possibility of gene manipulation may be a step towards the personalized treatment of breast cancer, which has so far remained unattainable due to the high heterogeneity of breast cancer
Upregulation of miR‐9 and miR‐193b over human Th17 cell differentiation
Abstract Background Th17 cells are a newly discovered subset of CD4+ T cells known as key participants in various immune responses and inflammatory conditions including autoimmune diseases. Mi(cro)RNAs are a family of non‐coding RNAs that regulate numerous critical immune functions. Immuno‐miRNAs modulate cell biological processes in T cells, such as differentiation and function of Th17 cells. The aim of the present study is to investigate the expression of miR‐9‐5p, miR‐193b‐3p, and autoimmunity‐related genes during human Th17 cells differentiation. Methods Human naïve CD4+ T cells were purified from peripheral blood mononuclear cells (PBMCs) by magnetic cell sorting system (MACS) and their purity was checked by flow‐cytometric analysis. Naïve CD4+ T cells were cultured under Th17‐polarizing condition for 6 days. IL‐ 17 secretion was determined by means of enzyme‐linked immunosorbent assay (ELISA). Next, the expression levels of miRNAs and putative targets genes were assessed by qRT‐PCR at different time points of differentiation. Results Our result showed dramatic downregulation of TCF7, MAP3K1, ENTPD1, and NT5E genes during human Th17 differentiation. Polarization also had a significant inducible effect on the expression of miR‐9 and miR‐193b over differentiation of human Th17 cells. According to our results, miR‐9‐5p and miR‐193b‐3p may contribute to Th17 differentiation probably by inhibiting the expression of negative regulators of Th17 differentiation. Conclusion This study confirmed deregulation of TCF7, MAP3K1, ENTPD1, and NT5E genes in Th17 differentiation process and introduced miR‐9 and miR‐193b as Th17 cell‐associated miRNAs, making them good candidates for further investigations
Quantify the impacts of anthropogenic changes and climate variability on runoff changes in central plateau of Iran using nine methods
Abstract
Quantification of affecting factors on river regime changes can be greatly helpful for water resources planning and management in the basin. Both anthropogenic changes and climate variability have affected rivers’ regime and led to considerable social and economic impacts. Observations in most parts of the world indicate that the hydrological cycle has been influenced by human activity besides of climate variability. In this study, 9 different methods which are divided into three general categories have been used to determine the impact of anthropogenic changes and climate variability on runoff changes in two watersheds in the central plateau of Iran, including Ghaleh-Shahrokh and Javanmardi watersheds. The results indicate that climate variability plays a dominant role in runoff decline in the Ghaleh-Shahrokh watershed, accounting for 60.2% of the total decrease, while human activities accounted for 39.8 %. In the Javanmardi watershed, anthropogenic changes played a dominant role in runoff decline, accounting for 77.1% (on average). In comparison, 22.9% (on average) of the decrease was attributable to climate variability. Sensitivity analysis of the annual mean runoff shows that precipitation plays a key role in runoff changes in both study areas. After precipitation, changes in potential evapotranspiration and temperature have the greatest impact on the annual mean runoff in the studied watersheds, respectively. Comparison of the different applied methods indicate that elasticity-based methods are the fastest and intuitive methods to investigate the impacts of anthropogenic changes and climate variability on runoff changes. Despite this, using different methods should be taken into account
Crosstalk between lncRNAs in the apoptotic pathway and therapeutic targets in cancer
The assertion that a significant portion of the mammalian genome has not been translated and that non-coding RNA accounts for over half of polyadenylate RNA have received much attention. In recent years, increasing evidence proposes non-coding RNAs (ncRNAs) as new regulators of various cellular processes, including cancer progression and nerve damage. Apoptosis is a type of programmed cell death critical for homeostasis and tissue development. Cancer cells often have inhibited apoptotic pathways. It has recently been demonstrated that up/ down-regulation of various lncRNAs in certain types of tumors shapes cancer cells' response to apoptotic stimuli. This review discusses the most recent studies on lncRNAs and apoptosis in healthy and cancer cells. In addition, the role of lncRNAs as novel targets for cancer therapy is reviewed here. Finally, since it has been shown that lncRNA expression is associated with specific types of cancer, the potential for using lncRNAs as biomarkers is also discussed
Transcriptional drug repositioning and cheminformatics approach for differentiation therapy of leukaemia cells
Abstract Differentiation therapy is attracting increasing interest in cancer as it can be more specific than conventional chemotherapy approaches, and it has offered new treatment options for some cancer types, such as treating acute promyelocytic leukaemia (APL) by retinoic acid. However, there is a pressing need to identify additional molecules which act in this way, both in leukaemia and other cancer types. In this work, we hence developed a novel transcriptional drug repositioning approach, based on both bioinformatics and cheminformatics components, that enables selecting such compounds in a more informed manner. We have validated the approach for leukaemia cells, and retrospectively retinoic acid was successfully identified using our method. Prospectively, the anti-parasitic compound fenbendazole was tested in leukaemia cells, and we were able to show that it can induce the differentiation of leukaemia cells to granulocytes in low concentrations of 0.1 μM and within as short a time period as 3 days. This work hence provides a systematic and validated approach for identifying small molecules for differentiation therapy in cancer