scholarly journals Phosphoinositides in Retinal Function and Disease

Cells ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 866 ◽  
Author(s):  
Theodore G. Wensel

Phosphatidylinositol and its phosphorylated derivatives, the phosphoinositides, play many important roles in all eukaryotic cells. These include modulation of physical properties of membranes, activation or inhibition of membrane-associated proteins, recruitment of peripheral membrane proteins that act as effectors, and control of membrane trafficking. They also serve as precursors for important second messengers, inositol (1,4,5) trisphosphate and diacylglycerol. Animal models and human diseases involving defects in phosphoinositide regulatory pathways have revealed their importance for function in the mammalian retina and retinal pigmented epithelium. New technologies for localizing, measuring and genetically manipulating them are revealing new information about their importance for the function and health of the vertebrate retina.

2020 ◽  
Author(s):  
Sean McCutcheon ◽  
Randy F. Stout ◽  
David C. Spray

AbstractGap junction (GJ) channels permit molecules, such as ions, metabolites and second messengers, to transfer between cells. Their function is critical for numerous cellular interactions. GJ channels are composed of Connexin (Cx) hexamers paired across extracellular space and typically form large rafts of clustered channels, called plaques, at cell appositions. Cxs together with molecules that interact with GJ channels make up a supramolecular structure known as the GJ Nexus. While the stability of connexin localization in GJ plaques has been studied, mobility of other Nexus components has yet to be addressed. Colocalization analysis of several nexus components and other membrane proteins reveal that certain molecules are excluded from the GJ plaque (Aquaporin 4, EAAT2b), while others are quite penetrant (lipophilic molecules, Cx30, ZO-1, Occludin). Fluorescence recovery after photobleaching (FRAP) of tagged Nexus-associated proteins showed that mobility in plaque domains is affected by mobility of the Cx proteins. These novel findings indicate that the GJ Nexus is a dynamic membrane organelle, with cytoplasmic and membrane-embedded proteins binding and diffusing according to distinct parameters.Summary StatementGap junctions are clustered membrane channels in plasma membrane of astrocytes and other cells. We report new information on how gap junctions control location and mobility of other astrocyte proteins.


Author(s):  
Klaus-Ruediger Peters

Only recently it became possible to expand scanning electron microscopy to low vacuum and atmospheric pressure through the introduction of several new technologies. In principle, only the specimen is provided with a controlled gaseous environment while the optical microscope column is kept at high vacuum. In the specimen chamber, the gas can generate new interactions with i) the probe electrons, ii) the specimen surface, and iii) the specimen-specific signal electrons. The results of these interactions yield new information about specimen surfaces not accessible to conventional high vacuum SEM. Several microscope types are available differing from each other by the maximum available gas pressure and the types of signals which can be used for investigation of specimen properties.Electrical non-conductors can be easily imaged despite charge accumulations at and beneath their surface. At high gas pressures between 10-2 and 2 torr, gas molecules are ionized in the electrical field between the specimen surface and the surrounding microscope parts through signal electrons and, to a certain extent, probe electrons. The gas provides a stable ion flux for a surface charge equalization if sufficient gas ions are provided.


Author(s):  
Aleksandr Mitin

The article discusses the possibilities of automation of legal activities. Special attention is paid to the new branch of the business LegalTech, which allows providing legal services using information technology. Some projects in this area are briefly described: FreshDoc document designer, VideoContract app, and electronic trading platforms such as Legal Space and Pravoved.Ru. Although the legal community is not quite ready to work in such conditions, higher education institutions are already reforming their curricula, developing disciplines that allow gaining professional competence in introducing technologies that automate legal work, and so on. The author, in turn, offers using chat bots in legal clinics, gives examples of new disciplines for master’s degree programs, considers the idea of passing final examinations outside universities in certification centers, etc. It is emphasized that in jurisprudence there are a lot of typical situations in which typical decisions need to be made, and here artificial intelligence will be a good helper, and scientists will have more time to undertake a comprehensive analysis of law. Thus, even with the advent of new technologies, the creative work of lawyers will always be in demand.


2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Kendall A. Johnson ◽  
Clive H. Bock ◽  
Phillip M. Brannen

Abstract Background Phony peach disease (PPD) is caused by the plant pathogenic bacterium Xylella fastidiosa subsp. multiplex (Xfm). Historically, the disease has caused severe yield loss in Georgia and elsewhere in the southeastern United States, with millions of PPD trees being removed from peach orchards over the last century. The disease remains a production constraint, and management options are few. Limited research has been conducted on PPD since the 1980s, but the advent of new technologies offers the opportunity for new, foundational research to form a basis for informed management of PPD in the U.S. Furthermore, considering the global threat of Xylella to many plant species, preventing import of Xfm to other regions, particularly where peach is grown, should be considered an important phytosanitary endeavor. Main topics We review PPD, its history and impact on peach production, and the eradication efforts that were conducted for 42 years. Additionally, we review the current knowledge of the pathogen, Xfm, and how that knowledge relates to our understanding of the peach—Xylella pathosystem, including the epidemiology of the disease and consideration of the vectors. Methods used to detect the pathogen in peach are discussed, and ramifications of detection in relation to management and control of PPD are considered. Control options for PPD are limited. Our current knowledge of the pathogen diversity and disease epidemiology are described, and based on this, some potential areas for future research are also considered. Conclusion There is a lack of recent foundational research on PPD and the associated strain of Xfm. More research is needed to reduce the impact of this pathogen on peach production in the southeastern U.S., and, should it spread internationally, wherever peaches are grown.


Electronics ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1208
Author(s):  
Francisco Alonso ◽  
Mireia Faus ◽  
Cristina Esteban ◽  
Sergio A. Useche

Technological devices are becoming more and more integrated in the management and control of traffic in big cities. The population perceives the benefits provided by these systems, and, therefore, citizens usually have a favorable opinion of them. However, emerging countries, which have fewer available infrastructures, could present a certain lack of trust. The objective of this work is to detect the level of knowledge and predisposition towards the use of new technologies in the transportation field of the Dominican Republic. For this study, the National Survey on Mobility was administered to a sample of Dominican citizens, proportional to the ONE census and to sex, age and province. The knowledge of ITS topics, as well as the use of mobile applications for mobility, are scarce; however, there was a significant increase that can be observed in only one year. Moreover, technology is, in general, positively assessed for what concerns the improvement of the traffic field, even though there is a lack of predisposition to provide one’s personal data, which is necessary for these devices. The process of technological development in the country must be backed up by laws that protect the citizens’ privacy. Thus, technologies that can improve road safety, mobility and sustainability can be implemented in the country.


2021 ◽  
Author(s):  
Daniel Hörcher ◽  
Ramandeep Singh ◽  
Daniel J. Graham

AbstractDense urban areas are especially hardly hit by the Covid-19 crisis due to the limited availability of public transport, one of the most efficient means of mass mobility. In light of the Covid-19 pandemic, public transport operators are experiencing steep declines in demand and fare revenues due to the perceived risk of infection within vehicles and other facilities. The purpose of this paper is to explore the possibilities of implementing social distancing in public transport in line with epidemiological advice. Social distancing requires effective demand management to keep vehicle occupancy rates under a predefined threshold, both spatially and temporally. We review the literature of five demand management methods enabled by new information and ticketing technologies: (i) inflow control with queueing, (ii) time and space dependent pricing, (iii) capacity reservation with advance booking, (iv) slot auctioning, and (v) tradeable travel permit schemes. Thus the paper collects the relevant literature into a single point of reference, and provides interpretation from the viewpoint of practical applicability during and after the pandemic.


World ◽  
2020 ◽  
Vol 1 (2) ◽  
pp. 171-190
Author(s):  
Diosey Ramon Lugo-Morin

The world is currently experiencing a pandemic: a virus in the family Coronaviridae is causing serious respiratory infections in humans. The outbreak of novel coronavirus disease (COVID-19) was declared a pandemic by the WHO on 11 March 2020. The outbreak began in December 2019 in Wuhan, China, and has since spread throughout the world. Despite measures taken by governments throughout the world to contain and control the spread, economic disruption at the global level is imminent and will affect all economic sectors, particularly the food sector. In a post-pandemic scenario, the use of new technologies will be decisive in a new model of food commercialization. The production and distribution of food will be configured to make supply chains optimal and safe systems. Against this background, the present study aims to explore and analyze the implications of the COVID-19 pandemic for global food security.


Electronics ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 1092 ◽  
Author(s):  
Sunddararaj ◽  
Rangarajan ◽  
Gopalan

The utilization of plug-in electric vehicles (PEV) has started to garner more attention worldwide considering the environmental and economic benefits. This has led to the invention of new technologies and motifs associated with batteries, bidirectional converters and inverters for Electric Vehicle applications. In this paper, a novel design and control of chopper circuit is proposed and configured with the series and parallel connection of the power electronic based switches for two-way operation of the converter. The bidirectional action of the proposed converter makes it suitable for plug-in electric vehicle applications as the grid is becoming smarter. The DC–DC converter is further interfaced with the designed multilevel inverter (MLI). The reduced switches associated with the novel design of MLI have overcome the cons associated with the conventional inverters in terms of enhanced performance in the proposed design. Further, novel control strategies have been proposed for the DC–DC converter based on Proportional Integral (PI) and Fuzzy based control logic. For the first time, the performance of the entire system is evaluated based on the comparison of proposed PI, fuzzy, and hybrid controllers. New rules have been formulated for the Fuzzy based controllers that are associated with the Converter design. This has further facilitated the interface of bidirectional DC–DC converter with the proposed MLI for an enhanced output voltage. The results indicate that the proposed hybrid controller provides better performance in terms of voltage gain, ripple, efficiency and overall aspects of power quality that forms the crux for PEV applications. The novelty of the design and control of the overall topology has been manifested based on simulation using MATLAB/SIMULINK.


1992 ◽  
Vol 2 (10) ◽  
pp. 287-304
Author(s):  
Ian Leigh

The broadcasting world is currently undergoing a revolution. The new technologies of cable and, more importantly, satellite broadcasting have brought within reach an enormous potential expansion and diversity in broadcasting. The Broadcasting Act 1990 is the government's response to the challenge, creating a mostly new regulatory framework. Alongside technological advance there has been a growing concern with regulating programme quality, as the creation of the Broadcasting Standards Commission (placed by Pt. V of the Act on a statutory footing) bears witness. A minor, but not insignificant, place in these cross-currents of ferment is occupied by religious broadcasting. This article seeks to place the controls and duties relating to religious broadcasting under the new regime within the context of its history in the UK and to consider the extent to which the new legal and administrative controls achieve an acceptable balance between religious expression and control of standards.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1618
Author(s):  
Yuichi Wakana ◽  
Felix Campelo

Membrane trafficking is essential for processing and transport of proteins and lipids and to establish cell compartmentation and tissue organization. Cells respond to their needs and control the quantity and quality of protein secretion accordingly. In this review, we focus on a particular membrane trafficking route from the trans-Golgi network (TGN) to the cell surface: protein kinase D (PKD)-dependent pathway for constitutive secretion mediated by carriers of the TGN to the cell surface (CARTS). Recent findings highlight the importance of lipid signaling by organelle membrane contact sites (MCSs) in this pathway. Finally, we discuss our current understanding of multiple signaling pathways for membrane trafficking regulation mediated by PKD, G protein-coupled receptors (GPCRs), growth factors, metabolites, and mechanosensors.


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