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Occurrence and growth of Vibrio cholerae, the causative agent of cholera, is linked to modalities of elevated temperatures and heavy precipitation. Previous studies have employed temperature- and s...

The roosting behaviour of two adult male Golden Eagles Aquila chrysaetos was studied using GPS satellite tags. One eagle (tag 816) used 120 different roost sites over two years and the other (tag 9...

Cross-linguistic studies of the lexicalization of motion tend to contrast satellite- with verb-framed languages (e.g. Slobin 1996; 2004; Cardini 2008; Özçalışkan & Slobin 2003; Kopecka 2004; Fargard et al. 2013, etc.) and concentrate less frequently on intra-typological analyses (but cf. e.g. Filipović 2007; Hasko 2010; Ibarretxe-Antuñano 2009; Ibarretxe-Antuñano & Hijazo-Gascón 2012). Even fewer studies contrast genetically related languages (but cf. e.g. Łozińska 2018). The main aim of this study was to establish the path-saliency cline of three satellite-framed languages: Polish, Russian, and English. The analysis was based on elicited data. The overall patterns of expressing the path of motion in the three languages were shown to be caused by their belonging to the same typological category. The differences could be attributed, to a large extent, to differences in the morphological structures and in the lexical repertoires of motion-coding expressions available to the speakers of the three languages. However, the analysis of descriptions of three specific spatial situations (i.e. vertical, boundary-crossing, and deictic relations) pointed to other factors that may influence path coding in the three languages. Thus, despite the satellite-verb character of the languages examined and the morpho-syntactic differences between them, all our participants, who were native speakers of the three languages examined, tended to code vertical relations by means of path verbs. The number of tokens of path verbs used to code this particular spatial relation was found to be higher than the number of tokens of path verbs used to code deictic or boundary-crossing motion., Das Hauptziel dieser Studie ist die Ermittlung der Grammatikalisierung des Pfad-Hervorragens in drei Satellite-Framed Languages: Polnisch, Russisch und Englisch. Die Analyse basierte auf hervorgerufenen Daten. Es wurde gezeigt, dass die allgemeinen Muster für den Ausdruck des Pfads der Bewegung in den drei Sprachen durch ihre Zugehörigkeit zur selben typologischen Kategorie begründet werden. Die Unterschiede können den Unterschieden in den morphologischen Strukturen und den lexikalischen Repertois von Bewegungs-kodierenden Ausdrücken zugeordnet werden, die den Sprechern der drei Sprachen zur Verfügung stehen. Die Analyse der Beschreibungen von drei räumlichen Situationen (d. h. vertikale, grenzüberschreitende und deiktische Beziehungen) deutete jedoch auf andere Faktoren, die die Pfadkodierung in den drei Sprachen beeinflussen können. Somit tendierten – trotz des Satelliten-Verb-Charakters der drei untersuchten Sprachen und der morpho-syntaktischen Unterschiede zwischen ihnen – alle unsere Teilnehmer zur Kodierung vertikaler Beziehungen mithilfe von Pfadverben. Die Anzahl der Zeichen von Pfadverben, die zur Kodierung dieser speziellen räumlichen Beziehung verwendet wurde, erwies sich als höher als die Anzahl der Zeichen von Pfadverben, die zur Kodierung von deiktischen oder grenzüberschreitenden Bewegungen verwendet wurden.

The incorporation of the cognitive radio (CR) technology as a spectrum management tool in satellite communication has attracted considerable research attention because the CR allows the coexistence of the primary and secondary networks using the same resources. In this paper, satellites and their users are considered as a primary network, and the terrestrial base stations (BSs) and their users are considered as a secondary network. Besides, it is considered that terrestrial users cause interference to satellite users due to technical and environmental constraints. This interference reduces satellite users' satisfaction with downloads rate. In such a cognitive satellite network environment, content placement may also cause a decrease in user satisfaction. The successful download probability (SDP) is analyzed in this work based on different terrestrial user density. To utilize the satellite cache resources effectively, we propose two transmission strategies based on the terrestrial user density, namely, the multi-point cooperative transmission strategy (CT) and the parallel transmission strategy (PT). In addition, based on the cache service probability we determine the ratio of content distribution most popular content (MPC) and general popular content (GPC) and optimize the content placement process using the utility function in CT mode. Through computer simulation, we give numerical results of our method. The obtained numerical results show that the proposed strategies are effective in content placement.

Tandem satellite repeats account for 3% of the human genome. One of them, Human Satellite II (HSATII), is highly expressed in several epithelial cancers and cancer cell lines. Here we report an acute induction of HSATII RNA in human cells infected with two herpes viruses. We show that human cytomegalovirus (HCMV) IE1 and IE2 proteins cooperate to induce HSATII RNA affecting several aspects of the HCMV replication cycle, viral titers and infected-cell processes. HSATII RNA expression in tissue from two chronic HCMV colitis patients correlates with the strength of CMV antigen staining. Thus, endogenous HSATII RNA synthesis after herpesvirus infections appears to have functionally important consequences for viral replication and may provide a novel insight into viral pathogenesis. The HSATII induction seen in both infected and cancer cells suggests possible convergence upon common HSATII-based regulatory mechanisms in these seemingly disparate diseases., The human genome includes a large amount of repetitive sequence, such as human satellite II (HSATII), but their function remains largely unknown. Here, Nogalski et al. show that herpesvirus infection induces HSATII RNA expression, which in turn affects virus replication and cell motility.

Satellite communication networks are expected to be indispensable as part of an integrated complement for the upcoming 5G networks since they can provide the most comprehensive coverage and reliable connection for areas where are economically unviable and/or difficult to deploy terrestrial infrastructures. Meanwhile, the power-domain non-orthogonal multiple access (NOMA), which can serve multiple users simultaneously within the same time/frequency block, has been viewed as another promising strategy used in the 5G network to provide high spectral efficiency and resource utilization. In this paper, we introduce a general overview of the application of the NOMA to various satellite architectures for the benefits of meeting the availability, coverage, and efficiency requirements targeted by the 5G. The fundamental and ubiquitous features of satellite link budget are first reviewed. Then, the advantage and benefit of introducing the NOMA scheme in various satellite architectures, such as conventional downlink/uplink satellite networks, cognitive satellite terrestrial networks, and cooperative satellite networks with satellite/terrestrial relays, are provided, along with the motivation and research methodology for each scenario. Finally, this paper reviews the potential directions for future research.

We have developed a one-pot strategy towards the synthesis of core–satellite structures based on the fractional precipitation rule. Benefiting from the multiple active contacts between the “core” and “satellite” materials, these structures show high catalytic activity in the CO oxidation reaction. This general synthetic method provides an alternative in the design of hybrid suprastructures.

Satellite glial cells surround neurons within dorsal root ganglia. Previous studies have focused on single-cell suspensions of cultured neurons derived from rat dorsal root ganglia. At present, the primary culture method for satellite glial cells derived from rat dorsal root ganglia requires no digestion skill. Hence, the aim of the present study was to establish a novel primary culture method for satellite glial cells derived from dorsal root ganglia. Neonatal rat spine was collected and an incision made to expose the transverse protrusion and remove dorsal root ganglia. Dorsal root ganglia were freed from nerve fibers, connective tissue, and capsule membranes, then rinsed and transferred to 6-well plates, and cultured in a humidified 5% CO2 incubator at 37°C. After 3 days in culture, some cells had migrated from dorsal root ganglia. After subculture, cells were identified by immunofluorescence labeling for three satellite glial cell-specific markers: glutamine synthetase, glial fibrillary acidic protein, and S100β. Cultured cells expressed glutamine synthetase, glial fibrillary acidic protein, and S100β, suggesting they are satellite glial cells with a purity of > 95%. Thus, we have successfully established a novel primary culture method for obtaining high-purity satellite glial cells from rat dorsal root ganglia without digestion.

Despite the many questions regarding satellite DNA sequences and their cellular roles, the evolutionary history of eukaryotic genomes seems to have been largely influenced by this dynamic and multifaceted genomic component. The bovine genome is highly rich in diverse satDNA sequences that differ in monomer sequence and length, complexity, chromosomal location and abundance, as well as in their sequences’ evolutionary mechanisms. In the evolution of the Bovidae family, the genomes’ repetitive fraction played a central role in karyotype reorganisation, and in the last few decades several studies have demonstrated and reinforced an association between centromeric satDNAs and the process of chromosome evolution in remodelling genomes of Bovidae species. Here, we review different aspects of the molecular nature and genome behaviour of all the satDNA families identified in the bovine genome, including their organisation, abundance, chromosome localisation, variation in sequence, and evolutionary history in the Bovidae family and in particular in the Bovinae subfamily, taking an integrative perspective. “Evolution and satDNA” can be addressed through two complementary views: the satDNA sequence evolution per se, and genome evolution promoted by the satDNA dynamism. SatDNA both provides phylogenetic information and is a critical genomic component that enables sequence and chromosome evolution – features arising from its presence, absence or alteration.

This workshop was held at the Teaching Satellite Meeting of the International Union of Physiological Sciences (IUPS), August 5–8, 2017, in Buzios, Rio de Janiero, Brazil. The satellite meeting was attended by physiology educators from across the globe, of whom 34 attended this workshop. The aim of the workshop was to explore how experimental design is taught to students of physiology in different institutions, to consider the aspects that students find challenging, to share good practice, and to think about how experimental design teaching could be improved. Through small-group discussions that were then shared with the whole group, participants were challenged to develop the outline of a research project to investigate a broad topic and then to identify the challenges that students might face if they were given that task. Finally, the group thought about what, in practical terms, could be done to help develop experimental design skills in undergraduates. The outcomes of the discussions are summarized in this report.

Many fungal viruses or mycoviruses have multi-segmented, rather than single-segmented, genomes. This multi-segment nature is frequently possessed by double-stranded RNA viruses, which include members of the Chrysoviridae, Quadriviridae, Megabirnaviridae, Partitiviridae, and Reoviridae families, and unassigned groups. Their genome segments are often packaged separately with the exception of mycoreoviruses, which are multi-segmented but mono-particulate viruses. These multi-segmented fungal dsRNA viruses, as exemplified by reoviruses, have been extensively studied among structural biologists, and contributed to discoveries of novel virion structures. Multi-component systems, interactions of viruses with subviral agents such as satellite and defective RNAs as typified by the yeast killer, and the rule-breaking neo-virus lifestyle exhibited by a capsidless single-stranded RNA virus hosted in an unrelated double-stranded RNA virus are also discussed. Fungal multi-segmented viruses and multicomponent virus systems would continue to provide virologists with interesting future challenges.

Summary Adult muscle stem cells (satellite cells) are required for adult skeletal muscle regeneration. A proper balance between quiescence, proliferation, and differentiation is essential for the maintenance of the satellite cell pool and their regenerative function. Although the ubiquitin-proteasome is required for most protein degradation in mammalian cells, how its dysfunction affects tissue stem cells remains unclear. Here, we investigated the function of the proteasome in satellite cells using mice lacking the crucial proteasomal component, Rpt3. Ablation of Rpt3 in satellite cells decreased proteasome activity. Proteasome dysfunction in Rpt3-deficient satellite cells impaired their ability to proliferate, survive and differentiate, resulting in defective muscle regeneration. We found that inactivation of proteasomal activity induced proliferation defects and apoptosis in satellite cells. Mechanistically, insufficient proteasomal activity upregulated the p53 pathway, which caused cell-cycle arrest. Our findings delineate a critical function of the proteasome system in maintaining satellite cells in adult muscle., Graphical Abstract, Highlights • Ablation of Rpt3 in satellite cells leads to decreased proteasome activity • Proteasome dysfunction in satellite cells results in defective muscle regeneration • Proteasome dysfunction induces proliferation defects and apoptosis • Inhibition of p53 rescues Rpt3-mediated defects in proliferation, It is not clear how proteasome insufficiency affects tissue stem cells. Kitajima et al. demonstrate that the proteasome system is indispensable for the maintenance of muscle stem cells. Proteasome dysfunction in Rpt3-deficient satellite cells impairs their ability to proliferate, survive and differentiate, resulting in defective muscle regeneration.

Here, for the first time, we analyzed skeletal muscle morphology in Boer and Nanjiang Brown (NJ) goats and then evaluated the differences in skeletal muscle satellite cells (SMSCs) proliferation and differentiation ability between the two breeds. Our results revealed that NJ goats had significantly more myofiber cells and a significantly smaller cross-section area compared with the Boer goats (P

Cell-cultured meat offers the potential for a more sustainable, ethical, resilient, and healthy food system. However, research and development has been hindered by the lack of suitable serum-free media that enable the robust expansion of relevant cells (e.g., muscle satellite cells) over multiple passages. Recently, a low-cost serum-free media (B8) was described for induced pluripotent stem cells. Here, we adapt this media for bovine satellite cells and show that the addition of a single component, recombinant albumin, renders B8 suitable for the long-term expansion of cells without sacrificing myogenicity. We show that this new media (Beefy-9) maintains robust cell growth over the entire culture period tested (seven passages) with an average growth rate of 39 hours per population doubling. Along with demonstrated efficacy for bovine cells, this work provides a promising starting-point for developing serum-free media for cultures from other meat-relevant species. Ultimately, this work offers a promising foundation for escaping the reliance on serum in cultured meat research, thereby accelerating the field.

Historically, adeno-associated virus (AAV)-defective interfering particles (DI) were known as abnormal virions arising from natural replication and encapsidation errors. Through single virion genome analysis, we revealed that a major category of DI particles contains a double-stranded DNA genome in a “snapback” configuration. The 5′- snapback genomes (SBGs) include the P5 promoters and partial rep gene sequences. The 3′-SBGs contains the capsid region. The molecular configuration of 5′-SBGs theoretically may allow double-stranded RNA transcription in their dimer configuration. Our studies demonstrated that 5-SBG regulated AAV rep expression and improved AAV packaging. In contrast, 3′-SBGs at its dimer configuration increased levels of cap protein. The generation and accumulation of 5′-SBGs and 3′-SBGs appears to be coordinated to balance the viral gene expression level. Therefore, the functions of 5′-SBGs and 3′-SBGs may help maximize the yield of AAV progenies. We postulate that AAV virus population behaved as a colony and utilizes its subgenomic particles to overcome the size limit of a viral genome and encodes additional essential functions.

The distinctive biology and unique evolutionary features of snakes make them fascinating model systems to elucidate how genomes evolve and how variation at the genomic level is interlinked with phenotypic-level evolution. Similar to other eukaryotic genomes, large proportions of snake genomes contain repetitive DNA, including transposable elements (TEs) and satellite repeats. The importance of repetitive DNA and its structural and functional role in the snake genome, remain unclear. This review highlights the major types of repeats and their proportions in snake genomes, reflecting the high diversity and composition of snake repeats. We present snakes as an emerging and important model system for the study of repetitive DNA under the impact of sex and microchromosome evolution. We assemble evidence to show that certain repetitive elements in snakes are transcriptionally active and demonstrate highly dynamic lineage-specific patterns as repeat sequences. We hypothesize that particular TEs can trigger different genomic mechanisms that might contribute to driving adaptive evolution in snakes. Finally, we review emerging approaches that may be used to study the expression of repetitive elements in complex genomes, such as snakes. The specific aspects presented here will stimulate further discussion on the role of genomic repeats in shaping snake evolution.

Recent studies implicate glutamate release from satellite glial cells (SGCs) surrounding the primary sensory neurons in the mechanisms of pathologic pain. However, little is known about the population of SGCs in the trigeminal ganglion that is involved in glutamate signaling associated with craniofacial neuropathic pain. To address this issue, we used quantitative analysis of electron microscopic immunogold labeling to investigate the changes in glutamate levels in trigeminal neurons and their enveloping SGCs in a rat model of craniofacial neuropathic pain, chronic constriction injury of inferior alveolar nerve (CCI-ION). The density of immunogold, a measure for glutamate concentration, in the neuronal cell bodies of all sizes, and in the SGCs surrounding them, was significantly higher in rats with CCI-ION than in sham-operated rats. This effect was more pronounced for the small neurons (2.2 times higher) and their SGCs (1.8 times higher) than for the medium and the large neurons and their SGCs, respectively. These findings suggest that each populations of SGCs and their surrounding trigeminal neurons of different type are involved in the glutamate signaling associated with neuropathic pain at a different level.

This chapter presents an overview of legacy, existing, and future advanced satellite systems for future wireless communications. The overview uses top-down approach, starting with a comparison between a typical commercial regular satellite system and a high-throughput satellite (HTS) system, following by a discussion on commonly used satellite network topologies. A discussion on the design of satellite payload architectures supporting both typical regular satellite and HTS with associated network topologies will be presented. Four satellite payload architectures will be discussed, including legacy analog bent-pipe satellite (ABPS); existing digital bent-pipe satellite (DBPS) and advanced digital bent-pipe satellite using digital channelizer and beamformer (AdDBPS-DCB); and future advanced regenerative on-board processing satellite (AR-OBPS) payload architectures. Additionally, various satellite system architectures using AdBP-DCBS and AR-OBPS payloads for the fifth-generation (5G) cellular phone applications will also be presented.

SummaryDNA methylation is an essential form of epigenetic regulation responsible for cellular identity. In muscle stem cells, termed satellite cells, DNA methylation patterns are tightly regulated during differentiation. However, it is unclear how these DNA methylation patterns are maintained. We demonstrate that a key epigenetic regulator, ubiquitin like with PHD and RING finger domains 1 (Uhrf1), is activated in proliferating myogenic cells but not expressed in quiescent or differentiated myogenic cells in mice. Ablation of Uhrf1 in mouse satellite cells impairs their proliferation and differentiation, leading to failed muscle regeneration. Loss of Uhrf1 in satellite cells alters transcriptional programs, leading to DNA hypomethylation with activation of Cdkn1a and Notch signaling. Although down-regulation of Cdkn1a rescued proliferation but not differentiation, inhibition of Notch signaling rescued impaired differentiation of Uhrf1-deficient satellite cells. These findings point to Uhrf1 as a regulator of self-renewal and differentiation of satellite cells via genome-wide DNA methylation patterning.

Muscle stem cells (MuSCs) also called satellite cells are the building blocks of skeletal muscle, the largest tissue in the human body which is formed primarily of myofibers. While MuSCs are the principal cells that directly contribute to the formation of the muscle fibers, their ability to do so depends on critical interactions with a vast array of nonmyogenic cells within their niche environment. Therefore, understanding the nature of communication between MuSCs and their niche is of key importance to understand how the skeletal muscle is maintained and regenerated after injury. MuSCs are rare and therefore difficult to study

Global satellite navigation system (GNSS) is by far the most cost-effective outdoor positioning technology currently available and used for many types of applications. In some cases a user may face difficult conditions, like restricted access to the navigation satellites due to natural or man-made phenomena. This paper presents an idea of an integrated positioning system capable of functioning under limited visibility conditions of navigation satellites. The system includes a digital antenna array, channels for converting radio navigation signals, a phase difference meter, a gyro platform with 3 gyros, an altimeter and a special calculator. With the help of mathematical modeling, the accuracy characteristics of the system are investigated by determining the coordinates of the carrier under conditions of a small number of available satellite signals.

Vector-borne parasites often manipulate hosts to attract uninfected vectors. For example, parasites causing malaria alter host odor to attract mosquitoes. Here we discuss the ecology and evolution of fruit-colonizing yeast in a tripartite symbiosis – the so-called “killer yeast” system. “Killer yeast” consists of Saccharomyces cerevisiae yeast hosting two double stranded RNA viruses (M satellite dsRNAs, L-A dsRNA helper virus). When both dsRNA viruses occur in a yeast cell, the yeast converts to lethal toxin‑producing “killer yeast” phenotype that kills uninfected yeasts. Yeasts on ephemeral fruits attract insect vectors to colonize new habitats. As the viruses have no extracellular stage, they depend on the same insect vectors as yeast for their dispersal. Viruses also benefit from yeast dispersal as this promotes yeast to reproduce sexually, which is how viruses can transmit to uninfected yeast strains. We tested whether insect vectors are more attracted to killer yeasts than to non‑killer yeasts. In our field experiment, we found that killer yeasts were more attractive to Drosophila than non-killer yeasts. This suggests that vectors foraging on yeast are more likely to transmit yeast with a killer phenotype, allowing the viruses to colonize those uninfected yeast strains that engage in sexual reproduction with the killer yeast. Beyond insights into the basic ecology of the killer yeast system, our results suggest that viruses could increase transmission success by manipulating the insect vectors of their host.

Cassava mosaic disease (CMD), which is caused by single-stranded DNA begomoviruses, severely limits cassava production across Africa. A previous study showed that CMD symptom severity and viral DNA accumulation increase in cassava in the presence of a DNA sequence designated as SEGS-2 (sequence enhancing geminivirus symptoms). We report here that when SEGS-2 is co-inoculated with African cassava mosaic virus (ACMV) onto Arabidopsis thaliana, viral symptoms increase. Transgenic Arabidopsis with an integrated copy of SEGS-2 inoculated with ACMV also display increased symptom severity and viral DNA levels. Moreover, SEGS-2 enables Cabbage leaf curl virus (CaLCuV) to infect a geminivirus resistant Arabidopsis accession. Although SEGS-2 is related to cassava genomic sequences, an earlier study showed that it occurs as episomes and is packaged into virions in CMD-infected cassava and viruliferous whiteflies. We identified SEGS-2 episomes in SEGS-2 transgenic Arabidopsis. The episomes occur as both double-stranded and single-stranded DNA, with the single-stranded form packaged into virions. In addition, SEGS-2 episomes replicate in tobacco protoplasts in the presence, but not the absence, of ACMV DNA-A. SEGS-2 episomes contain a SEGS-2 derived promoter and an open reading frame with the potential to encode a 75-amino acid protein. An ATG mutation at the beginning of the SEGS-2 coding region does not enhance ACMV infection in Arabidopsis. Together, the results established that SEGS-2 is a new type of begomovirus satellite that enhances viral disease through the action of a SEGS-2 encoded protein that may also be encoded in the cassava genome.IMPORTANCECassava is an important root crop in the developing world and a food and income crop for more than 300 million African farmers. Cassava is rising in global importance and trade as the demands for biofuels and commercial starch increase. More than half of the world’s cassava is produced in Africa, where it is primarily grown by smallholder farmers, many of whom are from the poorest villages. Although cassava can grow under high temperature, drought and poor soil conditions, its production is severely limited by viral diseases. Cassava mosaic disease (CMD) is one of the most important viral diseases of cassava and can cause up to 100% yield losses. We provide evidence that SEGS-2, which was originally isolated from cassava crops displaying severe and atypical CMD symptoms in Tanzanian fields, is a novel begomovirus satellite that can compromise the development of durable CMD resistance.

This study evaluates the latest Japanese Reanalysis for Three Quarters of a Century (JRA-3Q) conducted by the Japan Meteorological Agency (JMA), focusing on a semi-period of pre-satellite era (1960s and 1970s). The reanalysis is the third Japanese global atmospheric reanalysis covering the period from late 1940s onward, which is produced with the JMA's operational system as of December 2018. The atmospheric model has a TL479 horizontal resolution and 100 vertical layers up to 0.01 hPa, and the core component of the JRA-3Q data assimilation system is the 6-hourly 4D-Var of the atmospheric state with a T319-resolution inner model. Because there are only few global-covered observational datasets during the pre-satellite era, evaluation of the JRA-3Q is mainly to conduct an intercomparison of other reanalysis datasets such as representation Japanese 55-year Reanalysis (JRA-55), a JRA-55's subset of atmospheric reanalysis assimilating conventional observations only (JRA-55C), and version 3 of the Twentieth Century Reanalysis (20CRv3), and also an intercomparison of JRA-3Q between the pre-satellite and satellite eras. Emphasis of this evaluation during the non-satellite era is placed on the representation of tropical circulation, the consistency in time of the reanalysed fields, detection of tropical cyclones, and the quality of the stratospheric water vapor and ozone. For example, the surface circulation over the tropical Africa is improved by means of reducing spurious anticyclonic circulation anomalies that were found in JRA-55. Although the atmospheric model can produce self-generated quasi-biennial oscillation (QBO) by introducing non-orographic gravity wave drag, the evaluation reveals that JRA-3Q has a shorter period of around one year in the middle stratosphere and diminished QBO amplitude in the lower stratosphere, indicating that representation of the QBO in JRA-3Q is not as good as that in JRA-55.

A deep understanding of the responses of terrestrial vegetation to environmental forcing is crucial for understanding the global carbon dynamics, especially under a changing climate. Vegetation responses to stress can manifest first as plant physiological responses, and at later stages through changes in canopy structure. Remote sensing of vegetation has been proven very valuable in providing such understanding. One of the major breakthroughs has been the use of multi and hyper spectral sensors on board satellites that can retrieve Solar Induced Fluorescence (SIF), which is closely linked with plant photosynthesis.In this study we assess whether (SIF), as observed by instruments on board of satellites, can adequately capture both of those responses. Using 7 different global SIF products, water and CO2 flux data from 120 eddy-covariance towers and climate reanalysis products, we found a good agreement between the 16-day responses of flux tower observed gross primary productivity (GPP) and SIF to soil moisture and light, and a weaker agreement regarding the responses to temperature and atmospheric humidity. Overall, we found that current satellite SIF responses to environmental stressors mostly reflect structural changes in vegetation structure, and that satellite SIF has limited skill in capturing early stress plant physiological responses except for the light availability response at higher latitudes. While satellite SIF significantly outperforms more traditional vegetation indices (EVI, NDVI), as it does not saturate unlike the latter ones, it does not provide major additional information regarding vegetation physiological responses to either hydrological or atmospheric droughts.

Chlorine dioxide is an indicator for chlorine activation in the stratosphere, of importance for understanding spring-time ozone depletion processes in the polar regions of both hemispheres. Within the EUMETSAT AC SAF working group, chlorine dioxide (OClO) was retrieved from the GOME-2 instruments on MetOp-A and MetOp-B platforms, respectively over the time periods 2007-2016 and 2012-2016. Moreover, recent work performed as part of the S5p+ Innovation programme has led to the creation of an additional dataset derived from the TROPOMI instrument, extending the OClO time series in 2018-2020.This study analyses the quality of both OClO slant column (SCD) datasets by comparing them to ground-based DOAS zenith-sky measurements at a selection of 8 stations in Arctic and Antarctic regions: Eureka (80°N), Ny Alesund (79°N), Kiruna (68°N), Harestua (60°N), Marambio (64°S), Belgrano (78°S), Neumayer (71°S) and Arrival Heights (78°S). To allow for comparison with satellite data, ground-based OClO spectral analyses are performed using yearly fixed reference spectra recorded at low SZA in the absence of chlorine activation. Furthermore, an additional bias-correction is applied in post-processing to generate a consistent long-term OClO data record covering the 2007-2020 period.Daily comparisons of satellite and ground-based SCD data pairs corresponding to similar SZA conditions are performed, assuming similar stratospheric light paths in satellite nadir and ground-based zenith-sky geometries. Daily mean OClO SCD time-series show that satellite and ground-based observations agree well at all stations in terms of short-term variability and seasonal variation. Linear regression plots show a correlation coefficient R of about 0.97, a slope of 0.9 and an intercept of less than 1x1013 molec/cm² for TROPOMI, while for GOME-2 results are more noisy and tend to be biased low, with correlation coefficients between 0.76 and 0.88, slopes between 0.65 and 0.74 and intercepts up to 2.4 x1013 molec/cm².

Rift Valley fever virus (RVFV) is a mosquito-transmitted virus with proven ability to emerge into naïve geographic areas. Limited field evidence suggests that RVFV is transmitted vertically from parent mosquito to offspring, but until now this mechanism has not been confirmed in the laboratory. Furthermore, this transmission mechanism has allowed for the prediction of RVFV epizootics based on rainfall patterns collected from satellite information. However, in spite of the relevance to the initiation of epizootic events, laboratory confirmation of vertical transmission has remained an elusive research aim for thirty-five years. Herein we present preliminary evidence of the vertical transmission of RVFV by Culex tarsalis mosquitoes after oral exposure to RVFV. Progeny from three successive gonotrophic cycles were reared to adults, with infectious RVFV confirmed in each developmental stage. Virus was detected in ovarian tissues of parental mosquitoes 7 days after imbibing an infectious bloodmeal. Infection was confirmed in progeny as early as the first gonotrophic cycle, with infection rates ranging from 2.0–10.0%. Virus titers among progeny were low, which may indicate a host mechanism suppressing replication., Author summary Rift Valley fever virus (RVFV) represents a significant threat in terms of its ability to emerge into naïve geographic areas. Furthermore, RVFV represents a global public health risk due to the ability of many mosquito species to transmit the virus and the ease with which the virus can be transported due to increased globalization. The vertical transmission of RVFV by mosquitoes has long been accepted by the research community due to limited field evidence. However, laboratory confirmation of vertical transmission has remained elusive for thirty-five years. We present the first laboratory evidence of vertical transmission of RVFV in the susceptible North American vector, Culex tarsalis. We present two studies that clearly show 1) the accumulation of RVFV antigen in the ovaries of infected mosquitoes and 2) the transmission of RVFV from parent to offspring immediately following an infectious blood meal.

Summary Regeneration and repair of skeletal muscle is driven by tissue-specific progenitor cells called satellite cells, which occupy a minority of the cells in the muscle. This protocol provides researchers with techniques to efficiently isolate and purify functional satellite cells from human muscle tissue. The proven techniques described here enable the preparation of purified and minimally altered satellite cells for in vitro and in vivo experimentation and for potential clinical applications. For complete details on the use and execution of this protocol, please refer to Barruet et al. (2020) and Garcia et al. (2018)., Graphical Abstract, Highlights • Techniques are described for efficient isolation of human satellite cells • Quiescent and activated satellite cells are purified using surface markers • Purification involves minimal alteration compared to culture or activation • Purified satellite cells faithfully represent the natural state for applications, Regeneration and repair of skeletal muscle is driven by tissue-specific progenitor cells called satellite cells, which occupy a minority of the cells in the muscle. This protocol provides researchers with techniques to efficiently isolate and purify functional satellite cells from human muscle tissue. The proven techniques described here enable the preparation of purified and minimally altered satellite cells for in vitro and in vivo experimentation and for potential clinical applications.

Single Cell RNA-sequencing (scRNA-seq) is a powerful technique to deconvolute gene expression of various subset of cells intermingled within a complex tissue, such as the skeletal muscle. We first used scRNA-seq to understand dynamics of cell populations and their gene expression during muscle regeneration in murine limb muscles. This leads to the identification of a subset of satellite cells (the resident stem cells of skeletal muscles) with immune gene signatures in regenerating muscles. Next, we used scRNA-seq to examine gene expression dynamics of satellite cells at various status: quiescence, activation, proliferation, differentiation and self-renewal. This analysis uncovers stage-dependent changes in expression of genes related to lipid metabolism. Further analyses lead to the discovery of previously unappreciated dynamics of lipid droplets in satellite cells; and demonstrate that the abundance of the lipid droplets in newly divided satellite daughter cells is linked to cell fate segregation into differentiation versus self-renewal. Perturbation of lipid droplet dynamics through blocking lipolysis disrupts cell fate homeostasis and impairs muscle regeneration. Finally, we show that lipid metabolism regulates the function of satellite cells through two mechanisms. On one hand, lipid metabolism functions as an energy source through fatty acid oxidation (FAO), and blockage of FAO reduces energy production that is critical for satellite cell function. On the other hand, lipid metabolism generates bioactive molecules that influence signaling transduction and gene expression. In this scenario, lipid metabolism and FAO regulate the intracellular levels of acetyl-coA and selective acetylation of PAX7, a pivotal transcriptional factor underlying function of satellite cells. These results together reveal for the first time a critical role of lipid metabolism and lipid droplet dynamics in muscle satellite cell fate determination and regenerative function; and underscore a potential role of dietary fatty acids in satellite cell-dependent muscle development, growth and regeneration.

Suffolk ewes (n = 26) were blocked by body condition and weight, and randomly divided into two breeding groups (n = 13/group). One group was bred to a Texel ram and the other to a Suffolk ram. Ewes were confirmed pregnant by ultrasound and went to term. Male lambs (n = 4/sire/time) were harvested on d 2, 14, and 203 of age for muscle characterization and satellite cell isolation. From d 2 to 14, body weight increased (P < 0.01) by 80%, weight of the longissimus increased by 160%, and longissimus muscle area increased by 100%. Between d 14 and 203 lamb weight and weight of the longissimus increased by 350%, while longissimus area only increased by 100%. Sire breed did not alter lamb weight or weight of the longissimus (P > 0.10). Longissimus muscle area tended (P < 0.10) to be increased for Texel sired lambs when compared to Suffolk sired lambs. The total number of satellite cells isolated were not different by sire breed but did differ by animal age (P < 0.01). Satellite cell populations per gram of tissue increased between d 2 and 14 and decreased from d 14 to 203. Due to the large changes in growth from d2 to 14, satellite cell proliferation was examined at d 2 of age. Satellite cell proliferation capacity was altered by sire breed at d 2 of age potentially contributing to the increased longissimus muscle area. Advancing animal age and development alters satellite cell population numbers and potentially supports a high capacity for growth.

An amendment to this paper has been published and can be accessed via the original article.

This study explores links between NO2 emission and Covid-19 induced decline in consumption and mobility in Europe by using satellite images and various indices. This study discovered that strict lo...