bluuebunny/crossref_metadata_2025 huggingface dataset:
In vivo repair of a protein underlying a neurological disorder by programmable RNA editing
Authors: Sinnamon John R , Kim Susan Y , Fisk Jenna R , Song Zhen , Nakai Hiroyuki , Jeng Sophia , McWeeney Shannon K , Mandel Gail
Published: February 2020

RNA base editing is gaining momentum as an approach to repair mutations, but its application to neurological disease has not been established. We have succeeded in directed transcript editing of a pathological mutation in a mouse model of the neurodevelopmental disease, Rett syndrome. Specifically, we directed editing of a guanosine to adenosine mutation in RNA encoding Methyl CpG Binding Protein 2 (MECP2). Repair was mediated by injecting the hippocampus of juvenile Rett mice with an adeno-associated virus expressing both an engineered enzyme containing the catalytic domain of Adenosine Deaminase Acting on RNA 2 and aMecp2targeting guide. After one month, 50% ofMecp2RNA was recoded in three different hippocampal neuronal subtypes, and the ability of MeCP2 protein to associate with heterochromatin was similarly restored to 50% of wild-type levels. This study represents the firstin vivoprogrammable RNA editing applied to a model of neurological disease.
Frequency-specific suppression of locomotor components by thewhite+gene inDrosophila melanogasteradult flies
Authors: Xiao Chengfeng , Qiu Shuang
Published: February 2020

The classic eye-color genewhite+(w+) inDrosophila melanogaster(fruitfly) has unexpected behavioral consequences. Howw+affect locomotion of adult flies is largely unknown. Here, we show thatw+selectively suppresses locomotor components at relatively high frequencies (> 0.1 Hz). The wildtype Canton-S male flies walked intermittently in circular arenas while the white-eyedw1118flies walked continuously. Through careful control of genetic and cytoplasmic backgrounds, we found thatw+was associated with intermittent walking.w+-carrying male flies had smaller median values of path length per second (PPS) and reduced 5-min path length compared withw1118-carrying males. Additionally, flies carrying 2-4 genomic copies of mini-white+(mw+) showed reduced median PPSs and decreased 5-min path length compared withw1118flies, and the suppression was dependent on the copy number of mw+. Fourier transform of the time series (i.e. PPSs over time) indicated thatw+/mw+specifically suppressed the locomotor components at relatively high frequencies (> 0.1 Hz). Lastly, the downregulation ofw+in neurons but not glial cells resulted in an increased percentage of high-frequency locomotor components. We concluded thatw+suppressed the locomotion of adult flies by selectively reducing the high-frequency locomotor components.
Necrosignaling: Cell death triggers antibiotic survival pathways in bacterial swarms
Authors: Bhattacharyya Souvik , Walker David M. , Harshey Rasika M.
Published: February 2020

Swarming is form of collective bacterial motion enabled by flagella on the surface of semi-solid media1. Many bacterial species exhibit non-genetic adaptive resistance to a broad range of antibiotics only when swarming (SR)2-4. While the swarming population as a whole survives antibiotic challenge, it nonetheless sustains considerable cell death5. In this study focused mainly on E. coli, an initial analysis of antibiotic-induced killing patterns of swarm vs planktonic cells indicated that death of a sub-population is beneficial to the swarm in promoting SR. Introduction of pre-killed cells into a swarm indeed enhanced SR, allowing us to purify the SR factor from killed cells, and to establish that cell death is directly involved in SR. The SR-enhancing factor was identified to be AcrA, a periplasmic component of a tripartite RND efflux pump6, of which the outer membrane component TolC is shared by multiple drug efflux pumps7. We show that AcrA stimulates drug efflux in live cells by interacting with TolC from the outside. This stimulus acts as a signal to activate efflux in the short term, and to induce the expression of other classes of efflux pumps in the long term, amplifying the response and establishing SR. We call this phenomenon ‘necrosignaling’, and show the existence of species-specific necrosignaling in both Gram-positive and Gram-negative bacteria. Our results have implications for the adaptive resistance of other surface-associated bacterial collectives such as biofilms. Given that such resistance is known to be an incubator for evolving genetic resistance8, our findings may also be relevant to chemotherapy-resistant cancers.
The Taste of Blood in Mosquitoes
Authors: Jové Veronica , Gong Zhongyan , Hol Felix J.H. , Zhao Zhilei , Sorrells Trevor R. , Carroll Thomas S. , Prakash Manu , McBride Carolyn S. , Vosshall Leslie B.
Published: February 2020

Blood-feeding mosquitoes survive by feeding on nectar for metabolic energy, but to develop eggs, females require a blood meal.Aedes aegyptifemales must accurately discriminate between blood and nectar because detection of each meal promotes one of two mutually exclusive feeding programs characterized by distinct sensory appendages, meal sizes, digestive tract targets, and metabolic fates. We investigated the role of the syringe-like blood-feeding appendage, the stylet, and discovered that sexually dimorphic stylet neurons are the first to taste blood. Using pan-neuronal GCaMP calcium imaging, we found that blood is detected by four functionally distinct classes of stylet neurons, each tuned to specific blood components associated with diverse taste qualities. Furthermore, the stylet is specialized to detect blood over nectar. Stylet neurons are insensitive to nectar-specific sugars and responses to glucose, the sugar found in both blood and nectar, depend on the presence of additional blood components. The distinction between blood and nectar is therefore encoded in specialized neurons at the very first level of sensory detection in mosquitoes. This innate ability to recognize blood is the basis of vector-borne disease transmission to millions of people world-wide.
Candidate stress biomarkers for queen failure diagnostics
Authors: McAfee Alison , Milone Joseph , Chapman Abigail , Foster Leonard J , Pettis Jeffery S , Tarpy David R
Published: February 2020

Background

Queen failure is a persistent problem in beekeeping operations, but in the absence of overt symptoms it is often difficult, if not impossible, to ascertain the root cause. Stressors like heat-shock, cold-shock, and sublethal pesticide exposure can reduce stored sperm viability and lead to cryptic queen failure. Previously, we suggested candidate protein markers indicating heat-shock in queens, which we investigate further here, and tested new stressors to identify additional candidate protein markers.

Results

We found that heat-shocking queens for upwards of one hour at 40 °C was necessary to induce significant changes in the two strongest candidate heat-shock markers, and that relative humidity significantly influenced the degree of activation. In blind heat-shock experiments, we tested the efficiency of these markers at assigning queens to their respective treatment groups and found that one marker was sufficient to correctly assign queens 75% of the time. Finally, we compared cold-shocked queens at 4 °C and pesticide-exposed queens to controls to identify candidate markers for these additional stressors, and compared relative abundances of all markers to queens designated as ‘healthy’ and ‘failing’ by beekeepers.

Conclusions

This work offers some of the first steps towards developing molecular diagnostic tools to aid in determining cryptic causes of queen failure. Further work will be necessary to determine how long after the stress event a marker’s expression remains changed and how accurate these could be in the field.
Bambara Groundnut Rhizobacteria Antimicrobial and Biofertilization Potential
Authors: Ajilogba Caroline F. , Babalola Olubukola O. , Adebola Patrick , Adeleke Rasheed
Published: February 2020

Bambara groundnut, an underutilized crop has been proved to be an indigenous crop in Africa with the potential for food security. The rhizosphere of Bambara groundnut like other legumes contains several important bacteria that have not been explored for their plant growth-promoting properties. The aim of this research was to determine the potentials of rhizobacteria from Bambara groundnut soil samples as either biofertilizer or biocontrol agents or both to help provide sustainable agriculture in Africa and globally. Analyses of Bambara groundnut rhizospheric soil samples included chemical analysis such as nitrogen content analysis using extractable inorganic nitrogen method as well as cation exchangeable capacity using ammonium acetate method. Plant growth-promoting properties of isolated rhizobacteria tested include indole acetic acid, hydrogen cyanide, phosphate solubilization, 1-aminocyclopropane-1-carboxylate and ammonia production activities using standard methods. In addition, antifungal assay dual culture method was used to analyze the biocontrol properties of the isolates. Phylogenetic analysis using 16S rRNA was also carried out on the isolates. Isolated rhizobacteria from bambara groundnut rhizosphere were cultured. All the isolates were able to produce ammonia and 1-aminocyclopropane-1-carboxylate while 4.65%, 12.28% and 27.91% produced Hydrogen cyanide, Indole acetic acid and solubilized phosphate respectively, making them important targets as biocontrol and biofertilizer agents. The growth ofFusarium graminearumwas suppressedin vitroby 6.98% of the isolates. Plant growth promoting activities of rhizobacteria from bambara groundnut rhizosphere reveals that it has great potentials in food security as biofertilizer and biocontrol agent against fungal and bacterial pathogens.
Jekyll or Hyde? The genome (and more) ofNesidiocoris tenuis, a zoophytophagous predatory bug that is both a biological control agent and a pest
Authors: Ferguson K. B. , Visser S. , Dalíková M. , Provazníková I. , Urbaneja A. , Pérez-Hedo M. , Marec F. , Werren J. H. , Zwaan B. J. , Pannebakker B. A. , Verhulst E. C.
Published: February 2020

Nesidiocoris tenuis(Reuter) is an efficient predatory biological control agent used throughout the Mediterranean Basin in tomato crops but regarded as a pest in northern European countries. Belonging to the family Miridae, it is an economically important insect yet very little is known in terms of genetic information – no published genome, population studies, or RNA transcripts. It is a relatively small and long-lived diploid insect, characteristics that complicate genome sequencing. Here, we circumvent these issues by using a linked-read sequencing strategy on a single femaleN. tenuis. From this, we assembled the 355 Mbp genome and delivered anab initio, homology-based, and evidence-based annotation. Along the way, the bacterial “contamination” was removed from the assembly, which also revealed potential symbionts. Additionally, bacterial lateral gene transfer (LGT) candidates were detected in theN. tenuisgenome. The complete gene set is composed of 24,688 genes; the associated proteins were compared to other hemipterans (Cimex lectularis,Halyomorpha halys, andAcyrthosiphon pisum), resulting in an initial assessment of unique and shared protein clusters. We visualised the genome using various cytogenetic techniques, such as karyotyping, CGH and GISH, indicating a karyotype of 2n=32 with a male-heterogametic XX/XY system. Additional analyses include the localization of 18S rDNA and unique satellite probes via FISH techniques. Finally, population genomics via pooled sequencing further showed the utility of this genome. This is one of the first mirid genomes to be released and the first of a mirid biological control agent, representing a step forward in integrating genome sequencing strategies with biological control research.
High school Internship Program in Integrated Mathematical Oncology (HIP IMO) – five-year experience at Moffitt Cancer Center
Authors: Enderling Heiko , Altrock Philipp M. , Andor Noemi , Basanta David , Brown Joel S. , Gatenby Robert A. , Marusyk Andriy , Rejniak Katarzyna A. , Silva Ariosto , Anderson Alexander R.A.
Published: February 2020

Modern cancer research, and the wealth of data across multiple spatial and temporal scales, has created the need for researchers that are well-versed in the life sciences (cancer biology, developmental biology, immunology), medical sciences (oncology) and natural sciences (mathematics, physics, engineering, computer sciences). College undergraduate education is traditionally provided in disciplinary silos, which creates a steep learning curve at the graduate and postdoctoral levels that increasingly bridge multiple disciplines. Numerous colleges have begun to embrace interdisciplinary curricula, but students who double-major in mathematics (or other quantitative sciences) and biology (or medicine) remain scarce. We identified the need to educate junior and senior high school students about integrating mathematical and biological skills, through the lens of mathematical oncology, to better prepare students for future careers at the interdisciplinary interface. The High school Internship Program in Integrated Mathematical Oncology (HIP IMO) at Moffitt Cancer Center has so far trained 59 students between 2015 and 2019. We report here on the program structure, training deliverables, curriculum, and outcomes. We hope to promote such interdisciplinary educational activities early in a student’s career.
Evaluation of the functional role of the maizeGlossy2 and Glossy2-likegenes in cuticular lipid deposition
Authors: Alexander Liza Esther , Okazaki Yozo , Schelling Michael A. , Davis Aeriel , Zheng Xiaobin , Rizhsky Ludmila , Yandeau-Nelson Marna D. , Saito Kazuki , Nikolau Basil J.
Published: February 2020

Plant epidermal cells express unique molecular machinery that juxtapose the assembly of intracellular lipid components and the unique extracellular cuticular lipids that are unidirectionally secreted to plant surfaces. In maize (Zea maysL.), mutations at theglossy2 (gl2)locus affect the deposition of extracellular cuticular lipids. Sequence-based genome scanning identified a novelgl2homolog in the maize genome,Gl2-like. Sequence homology identifies that both theGl2-likeandGl2genes are members of the BAHD superfamily of acyltransferases, with close sequence homology to the ArabidopsisCER2gene. Transgenic experiments demonstrate thatGl2-likeandGl2functionally complement the Arabidopsiscer2mutation, with differential impacts on the cuticular lipids and the lipidome of the plant, particularly affecting the longer alkyl chain acyl lipids, particularly at the 32-carbon chain length. Site-directed mutagenesis of the putative BAHD catalytic HXXXDX-motif indicates thatGl2-likerequires this catalytic capability to fully complement thecer2function, butGl2can accomplish this without the need for this catalytic motif. These findings demonstrate that bothGl2andGl2-likeoverlap in their cuticular lipid function, however the two genes have evolutionary diverged to acquire non-overlapping functions.

One-sentence summary

Transgenesis dissection of the functional roles of the maizeGlossy2andGlossy2-Likegenes in cuticular lipid deposition.
Spiking attractor model of motor cortex explains modulation of neural and behavioral variability by prior target information
Authors: Rostami Vahid , Rost Thomas , Schmitt Felix J. , van Albada Sacha J. , Riehle Alexa , Nawrot Martin P.
Published: February 2020

When preparing a movement, we often rely on partial or incomplete information, which can decrement task performance. In behaving monkeys we show that the degree of cued target information is reflected in both, neural variability in motor cortex and behavioral reaction times. We study the underlying mechanisms in a spiking motor-cortical attractor model. By introducing a novel and biologically realistic network topology where excitatory neuron clusters are locally balanced with inhibitory neuron clusters we robustly achieve metastable network activity across a wide range of network parameters. In application to the monkey task, the model performs target-specific action selection and accurately reproduces the task-epoch dependent reduction of trial-to-trial variabilityin vivowhere the degree of reduction directly reflects the amount of processed target information, while spiking irregularity remained constant throughout the task. In the context of incomplete cue information, the increased target selection time of the model can explain increased behavioral reaction times . We conclude that context-dependent neural and behavioral variability is a signum of attractor computation in the motor cortex.
Nanobody-dependent delocalization of endocytic machinery in Arabidopsis root cells dampens their internalization capacity
Authors: Winkler Joanna , De Meyer Andreas , Mylle Evelien , Grones Peter , Storme Veronique , Van Damme Daniël
Published: February 2020

Plant cells perceive and adapt to an ever-changing environment by modifying their plasma membrane (PM) proteome. Whereas secretion deposits new integral membrane proteins, internalization by endocytosis removes membrane proteins and associated ligands, largely with the aid of adaptor protein complexes and the scaffolding molecule clathrin. Two adaptor protein complexes function in clathrin-mediated endocytosis at the PM in plant cells, the heterotetrameric Adaptor Protein 2 (AP-2) complex and the octameric TPLATE complex (TPC). Whereas single subunit mutants in AP-2 develop into viable plants, genetic mutation of a single TPC subunit causes fully penetrant male sterility and silencing single subunits leads to seedling lethality. To address TPC function in somatic root cells, while minimizing indirect effects on plant growth, we employed nanobody-dependent delocalization of a functional, GFP-tagged TPC subunit, TML, in its respective homozygous genetic mutant background. In order to decrease the amount of functional TPC at the PM, we targeted our nanobody construct to the mitochondria and fused it to TagBFP2 to visualize it independently of its bait. We furthermore limited the effect of our delocalization to those tissues that are easily accessible for live-cell imaging by expressing it from the PIN2 promotor, which is active in root epidermal and cortex cells. With this approach, we successfully delocalized TML from the PM. Moreover, we also show co-recruitment of TML-GFP and AP2A1-TagRFP to the mitochondria, suggesting that our approach delocalized complexes, rather than individual adaptor complex subunits. In line with the specific expression domain, we only observed minor effects on root growth, yet realized a clear reduction of endocytic flux in epidermal root cells. Nanobody-dependent delocalization in plants, here exemplified using a TPC subunit, has the potential to be widely applicable to achieve specific loss-of-function analysis of otherwise lethal mutants.
Deep-sea corals near cold seeps associate with chemoautotrophic bacteria that are related to the symbionts of cold seep and hydrothermal vent mussels
Authors: Vohsen Samuel A. , Gruber-Vodicka Harald R. , Osman Eslam O. , Saxton Matthew A. , Joye Samantha B. , Dubilier Nicole , Fisher Charles R. , Baums Iliana B.
Published: February 2020

Cnidarians are known for their symbiotic relationships, yet no known association exists between corals and chemoautotrophic microbes. Deep-sea corals, which support diverse animal communities in the Gulf of Mexico, are often found on authigenic carbonate in association with cold seeps. Sulfur-oxidizing chemoautotrophic bacteria of the SUP05 cluster are dominant symbionts of bathymodiolin mussels at cold seeps and hydrothermal vents around the world and have also been found in association with sponges. Therefore, we investigated whether other basal metazoans, corals, also associate with bacteria of the SUP05 cluster and report here that such associations are widespread. This was unexpected because it has been proposed that cnidarians would not form symbioses with chemoautotrophic bacteria due to their high oxygen demand and their lack of specialized respiratory structures. We screened corals, water, and sediment for SUP05 using 16S metabarcoding and found SUP05 phylotypes associated with corals at high relative abundance (10 – 91%). These coral-associated SUP05 phylotypes were coral host specific, absent in water samples, and rare or not detected in sediment samples. The genome of one SUP05 phylotype associated withParamuriceasp. type B3, contained the genetic potential to oxidize reduced sulfur compounds and fix carbon and these pathways were transcriptionally active. Finally, the relative abundance of this SUP05 phylotype was positively correlated with chemoautotrophically-derived carbon and nitrogen input into the coral holobiont based on stable carbon and nitrogen isotopic compositions. We propose that SUP05 may supplement the diet of its host coral through chemoautotrophy or may provide nitrogen, essential amino acids, or vitamins. This is the first documented association between a chemoautotrophic symbiont and a cnidarian, broadening the known symbioses of corals and may represent a novel interaction between coral communities and cold seeps.
Exploring a natural baseline for large herbivore biomass
Authors: Fløjgaard Camilla , Pedersen Pil Birkefeldt , Sandom Christopher J. , Svenning Jens-Christian , Ejrnæs Rasmus
Published: February 2020

The massive global losses of large mammals in the Pleistocene have triggered severe ecosystem changes including changed nutrient cycles, fire regimes and climate, shifts in biomes and loss of biodiversity. Large herbivores create and diversify resources and living space for other organisms and thereby play an important role in ecosystem functioning and biodiversity conservation. However, even today large herbivores are regulated, hunted and driven to extinction to a degree where intact large-herbivore communities are largely non-existent. Consequently, natural density and biomass of large-herbivores for restoration of ecosystems are poorly known. To address this knowledge gap, we apply the scaling pattern for consumer-producer relationships and show that the biomass of large herbivores in ecosystems across the world is considerably lower than expected from primary productivity. African ecosystems have the strongest consumer-producer relationship and assuming that African ecosystems approach a natural baseline, we use this relationship to predict large herbivore biomass in Europe as an example. Our findings indicate that restoring large herbivore biomass would entail increasing large herbivore biomass by orders of magnitude in most ecosystems, which potentially changes the perspective on large herbivores in conservation and restoration projects.
S1PR1 regulates the quiescence of lymphatic vessels by inhibiting laminar shear stress-dependent VEGF-C signaling
Authors: Geng Xin , Yanagida Keisuke , Akwii Racheal G. , Choi Dongwon , Chen Lijuan , Ho YenChun , Cha Boksik , Mahamud Md. Riaj , de Ruiz Karen Berman , Ichise Hirotake , Chen Hong , Wythe Joshua , Mikelis Constantinos M. , Hla Timothy , Srinivasan R. Sathish
Published: February 2020

During the growth of lymphatic vessels (lymphangiogenesis), lymphatic endothelial cells (LECs) at the growing front sprout by forming filopodia. Those tip cells are not exposed to circulating lymph, as they are not lumenized. In contrast, LECs that trail the growing front are exposed to shear stress, become quiescent and remodel into stable vessels. The mechanisms that coordinate the opposed activities of lymphatic sprouting and maturation remain poorly understood. Here we show that the canonical tip cell marker Delta-Like 4 (DLL4) promotes sprouting lymphangiogenesis by enhancing Vascular Endothelial Growth Factor C (VEGF-C) /VEGF Receptor 3 (VEGFR3) signaling. However, in lumenized lymphatic vessels laminar shear stress (LSS) inhibits the expression of DLL4, as well as additional tip cell markers. Paradoxically, LSS also upregulates VEGF-C/VEGFR3 signaling in LECs, but sphingosine 1-phosphate (S1P) receptor 1 (S1PR1) activity antagonizes LSS-mediated VEGF-C signaling to promote lymphatic vascular quiescence. Correspondingly,S1pr1loss in LECs induced lymphatic vascular hypersprouting and hyperbranching, which could be rescued by reducingVegfr3gene dosagein vivo. In addition, S1PR1 regulates lymphatic vessel maturation by promoting membrane localization of the tight junction molecule Claudin-5. Our findings suggest a new paradigm in which LSS induces quiescence and promotes the survival of LECs by downregulating DLL4 and enhancing VEGF-C signaling, respectively. S1PR1 dampens LSS/VEGF-C signaling, thereby preventing sprouting from quiescent lymphatic vessels. These results also highlight the distinct roles that S1PR1 and DLL4 play in LECs when compared to their known roles in the blood vasculature.
Mapping Spatially Distributed Material Properties in Finite Element Models of Plant Tissue Using Computed Tomography
Authors: Stubbs Christopher J , Larson Ryan , Cook Douglas D
Published: February 2020

Plant tissues are often heterogeneous. To accurately investigate these tissues, we will need methods to spatially map these tissue stiffness values onto finite element models. The purpose of this research is to develop a method for using specimen-specific computed tomography data to inform the spatial mapping of Young’s modulus values on finite element models. The spatial mapping of Young’s modulus was calculated and then used to predict the response of specimen tests. Results indicated that this method can be used to obtain spatial distributions of material properties, thus enabling finite element models that account for material heterogeneity.
Learning prediction error neurons in a canonical interneuron circuit
Authors: Hertäg Loreen , Sprekeler Henning
Published: February 2020

Sensory systems constantly compare external sensory information with internally generated predictions. While neural hallmarks of prediction errors have been found throughout the brain, the circuit-level mechanisms that underlie their computation are still largely unknown. Here, we show that a well-orchestrated interplay of three interneuron types shapes the development and refinement of negative prediction-error neurons in a computational model of mouse primary visual cortex. By balancing excitation and inhibition in multiple pathways, experience-dependent inhibitory plasticity can generate different variants of prediction-error circuits, which can be distinguished by simulated optogenetic experiments. The experience-dependence of the model circuit is consistent with that of negative prediction-error circuits in layer 2/3 of mouse primary visual cortex. Our model makes a range of testable predictions that may shed light on the circuitry underlying the neural computation of prediction errors.
Differential glycosylation of alpha-1-acid glycoprotein (AGP-1) contributes to its functional diversity
Authors: Sumanth Mosale Seetharam , Jacob Shancy P , Abhilasha Kandahalli Venkataranganayaka , Manne Bhanu Kanth , Basrur Venkatesha , Lehoux Sylvain , Campbell Robert A , Yost Christian C , Rhondina Matthew T , McIntyre Thomas M , Cummings Richard D , Weyrich Andrew S , Marathe Gopal K
Published: February 2020

Alpha-1-acid glycoprotein (AGP-1) is a positive acute phase glycoprotein with uncertain functions. Serum AGP-1 (sAGP-1) is primarily derived from hepatocytes and circulates as 12 to 20 different glycoforms. We isolated a glycoform secreted from stimulated human neutrophils (nAGP-1). Its peptide sequence was identical to hepatocyte-derived sAGP-1, but nAGP-1 differed from sAGP-1 in its chromatographic behaviour, electrophoretic mobility, and glycosylation. The function of these two glycoforms also differed. sAGP-1 activated neutrophil adhesion, migration and NETosis in a dose-dependent fashion, while nAGP-1 was ineffective as an agonist for these events. Furthermore, sAGP-1, but not nAGP-1, inhibited LPS-stimulated NETosis. However, nAGP-1 inhibited sAGP-1-stimulated neutrophil NETosis. The discordant effect of the differentially glycosylated AGP-1 glycoforms was also observed in platelets where neither of the AGP-1 glycoforms alone stimulated aggregation of washed human platelets, but sAGP-1, and not nAGP-1, inhibited aggregation induced by Platelet-activating Factor (PAF) or ADP, but not by thrombin. These functional effects of sAGP-1 correlated with intracellular cAMP accumulation and were accompanied by phosphorylation of the PKA substrate Vasodialator stimulated phosphoprotein (VASP) and reduction of Akt, ERK, and p38 phosphorylation. Thus, the sAGP-1 glycoform limits platelet reactivity while nAGP-1 glycoform also limits pro-inflammatory actions of sAGP-1. These studies identify new functions for this acute phase glycoprotein and demonstrate that the glycosylation of AGP-1 controls its effects on two critical cells of acute inflammation.
Bacterial Community Composition and Diversity along the Southern Coastlines of the Atlantic Ocean in Cape Town, South Africa
Authors: Olapade Ola A.
Published: February 2020

The spatial distribution and diversity within bacterioplankton assemblages in four coastal sites along the southern points of the Atlantic Ocean were examined using the Illumina high-throughput that targets 16S rRNA genes to examine indigenous bacterial assemblages in the littoral zones along the coast of the ocean. Results of the study showed very similar bacterial representation between the coastal sites with majority of the sequences affiliated with Proteobacteria (52 to 59%), Bacteriodetes (21 to 31%) followed by Actinobacteria (3 to 9.5%) and Planctomycetes (2.1 to 4.5%). The bacterioplankton assemblages at each site examined were quite diverse, with members of the Gammaproteobacteria found as the most abundant bacterial class among the four sites. However, clear differences were observed among the sites at the order level, with the Chromatiales the more dominant in the closer CPTI sites, while clades belonging to the Flavobacteriales and Rhodobacterales were more prevalent in the two CPTA sites. While the results of UPGMA clustering and principle coordinate (PCoA) revealed two spatially separate clusters among sites, canonical correspondence (CCA) analysis indicated that environmental variables such as temperature, pH and conductivity were probably the major influencers of bacterial occurrences at the coastal sites.
Social networks feed the food supplements shadow market
Authors: Sfodera Fabiola , Mattiacci Alberto , Nosi Costanza , Mingo Isabella
Published: March 2020

Purpose

The paper investigates the role of social networks in the millennials’ decision-making process of illegal and unnotified food supplements purchase. The connections and interactions that (co) produce information are studied with a holistic perspective of social sustainability as a development driver of business model innovation.

Design/methodology/approach

An exploratory qualitative multiple analysis study was conducted in two consecutive phases. Data from 23 semi-structured individual interviews were collected, followed by a netnographic analysis of the Facebook virtual community.

Findings

The results show that the decision-making process does not develop following the traditional sequence, as social networks modify the wellness meaning creation process and reduce risk perception. Moreover, social networks introduce the use of similar experiences of others and online information and emotional support on unethical and unhealthy behavior.

Research limitations/implications

Due to the application to a social network, the results should be understood within this context. Future studies would benefit by expanding the target and the range of social networks explored.

Practical implications

The official information quality control, as a prerogative of public and professional health stakeholders, and the medialization of medicalization, contribute to the conscious development of their wellness meanings and values.

Originality/value

This work represents one of the first attempts to investigate resources integration through social networks in the pre-purchase decision-making process of unnotified and illegal food supplements. Unethical and unhealthy behavior develops through the interaction of actors, firms, influencers and individuals over social networks.
Reliability modeling of multi-version software system incorporating the impact of infected patching
Authors: Anand Adarsh , Kaur Jasmine , Inoue Shinji
Published: February 2020

Purpose

The purpose of the present work is to mathematically model the reliability growth of a multi-version software system that is affected by infected patches.

Design/methodology/approach

The work presents a mathematical model that studies the reliability change due to the insertion of an infected patch in multi-version software. Various distribution functions have been considered to highlight the varied aspects of the model. Furthermore, weighted criteria approach has been discussed to facilitate the choice of the model.

Findings

The model presented here is able to quantify the effect of an infected patch on multi-version software. The model captures the hike in bug content due to an infected patch.

Originality/value

Multi-version systems have been studied widely, but the role of an infected patch has not been yet explored. The effect of an infected patch has been quantified by modeling the extra bugs generated in the system. This bug count would prove helpful in further studies for optimal resource allocation and testing effort allocation.
Measuring online live streaming of perceived servicescape
Authors: Chen Yu-Hsin , Chen Min-Cing , Keng Ching-Jui
Published: February 2020

Purpose

This study aimed to develop and validate an online live streaming perceived servicescape (OLSPS) scale that can help platform service providers to develop strategies for new live streaming channel promotions.

Design/methodology/approach

This study conceptualized the construct of OLSPS and the four-phase procedure of the 66-item OLSPS scale development, including item generation, item purification, scale validation, measure application and testing of hypotheses. It also provided a research framework to assess audiences' cognition and behavioral intention, and an online survey on 420 live streaming users (social platforms, n = 210; native platforms, n = 210) was conducted.

Findings

This study developed and validated a 35-item OLSPS scale with eight dimensions. The results of the empirical model showed that OLSPS is positively correlated with the audiences' cognition and behavioral intention. Furthermore, parasocial interaction experience showed a positive moderation on channel trust.

Originality/value

This study is a pioneering effort to develop and validate an OLSPS scale. The results could be helpful for researchers in building OLSPS and for managers in assessing and promoting users' acceptance of online live streaming platforms.
Mycoheterotrophic plants living on arbuscular mycorrhizal fungi are generally enriched in 13C, 15N and 2H isotopes
Authors: Gomes Sofia I. F. , Merckx Vincent S. F. T. , Kehl Judith , Gebauer Gerhard
Published: February 2020

Fully mycoheterotrophic plants are thought to obtain carbon exclusively from their root‐associated fungal partners. The general enrichment of these plants in the heavy isotopes 13C and 15N suggests that fungi are the main nutrient source for these plants. Yet, the majority of studies have targeted mycoheterotrophic plants associated with ectomycorrhizal, orchid mycorrhizal and saprotrophic fungi, while mycoheterotrophic plants living on arbuscular mycorrhizal fungi remain understudied.

Here, we sampled 13 species of arbuscular mycorrhizal fully mycoheterotrophic plants from five families and co‐occurring autotrophic reference plants growing in forests of tropical South America, tropical South East Asia and temperate Australasia. We measured stable isotope natural abundances (δ13C, δ15N, δ2H and δ18O), determined total nitrogen concentrations and used high‐throughput DNA sequencing to characterize the arbuscular mycorrhizal fungal communities associated with the sampled mycoheterotrophic plants.

We observed a general enrichment in 13C and 15N isotopes across mycoheterotrophic plant families and geographic regions. We confirm cases where no 15N enrichment is present, but we show that in general arbuscular mycoheterotrophic plants are enriched in 15N. Moreover, we demonstrate for the first time that these plants are significantly enriched in 2H but not in 18O in relation to their autotrophic references. The fungal communities targeted by the mycoheterotrophs mainly consist of Glomeraceae and show strong association with the isotopic signatures and geographic origin of the plants.

Synthesis. Our findings enlarge the limited knowledge on the multi‐element stable isotopic signatures of mycoheterotrophic plants living on arbuscular mycorrhizal fungi. We show that these plants are enriched in 13C and 2H as expected due to their mycoheterotrophic nutrition, and that in general they are also enriched in 15N, despite some exceptions. Variation in stable isotope signatures is likely influenced by plant taxonomy, geography and fungal community composition.
Azo dying of α‐keratin material improves microbial keratinase screening and standardization
Authors: Gonzalo Milena , Espersen Roall , Al‐Soud Waleed A. , Cristiano Falco Francesco , Hägglund Per , Sørensen Søren J. , Svensson Birte , Jacquiod Samuel
Published: February 2020

Microbial conversion through enzymatic reactions has received a lot of attention as a cost‐effective and environmentally friendly way to recover amino acids and short peptides from keratin materials. However, accurate assessment of microbial keratinase activity is not straightforward, and current available methods lack sensitivity and standardization. Here, we suggest an optimized Azokeratin assay, with substrate generated directly from azo‐dyed raw keratin material. We introduced supernatant filtration in the protocol for optimal stopping of keratinase reactions instead of the widely used trichloroacetic acid (TCA), as it generated biases and impacted the sensitivity. We furthermore suggest a method for standardization of keratinase activity signals using proteinase K, a well‐known keratinase, as a reference enabling reproducibility between studies. Lastly, we evaluated our developed method with several bacterial isolates through benchmarking against a commercial assay (Keratin Azure). Under different setups, the Azokeratin method was more sensitive than commonly used Keratin Azure‐based assays (3‐fold). We argue that this method could be applied with any type of keratin substrate, enabling more robust and sensitive results which can be used for further comparison with other studies, thus representing an important progress within the field of microbial keratin degradation.
US Foreign Policy in the Middle East: The Logic of Hegemonic Retreat
Authors: Yom Sean
Published: February 2020

The Trump administration's foreign policy is often perceived as an isolationist ideology that has radically reversed American global leadership in a matter of years. In the Middle East, critics have harangued the Trump Doctrine as an even hastier surrender of the US hegemony that has defined regional order since the 1980s. In reality, American interest in this region has been declining for a decade as expressed by its rising reluctance to leverage its economic and military supremacy to constrain, regulate, and destroy perceived foes as it once did. This waning interventionism precedes the Trump Doctrine. It stems not from any ideological turn, or the financial and military exhaustion of a cresting superpower, but rather a structural dynamic: the Middle East no longer generates credible threats against the US. Whereas in the past alarmist fears of communism and energy insecurity propelled Washington's regional imperium, today the perceived enemies of US interests – radical Islamism and Iran – do not endanger the political institutions and economic prosperity of American society. Absent a catastrophic terrorist attack, the US will continue to relinquish its hegemonic mantle, turning away from overt interventionism as the logic of coercively dominating a region of diminishing importance runs its course.
Effectiveness of WhatsApp online group discussion for smoking relapse prevention: protocol for a pragmatic randomized controlled trial
Authors: Cheung Yee Tak Derek , Chan Ching Han Helen , Ho Kin Sang , Fok Wai‐Yin Patrick , Conway Mike , Wong Carlos King Ho , Li William Ho Cheung , Wang Man Ping , Lam Tai Hing
Published: February 2020

Background and aims

Sustained psychosocial support via online social groups may help former tobacco users maintain abstinence. This study aims to examine the effectiveness of participating in a WhatsApp social group for long‐term smoking cessation.

Design

Two‐arm, open‐labelled, pragmatic, individually randomized controlled trial.

Setting

All participants are service users of smoking cessation clinics, and all interventions are delivered via mobile phones.

Participants

Participants included 1008 adult quitters who self‐report no tobacco use in the past 3–30 days.

Interventions

The intervention group (n = 504) will join a WhatsApp social group to receive standardized and theory‐based reminders of smoking relapse prevention and participate in discussion with other WhatsApp group members using their own mobile phones. All social groups will be led by counselors or specialist nurse practitioners. The control group (n = 504) will receive similar reminders via short messages to their own mobile phones but will not interact with other participants. The intervention duration for both groups is 8 weeks. Both groups will receive a booklet at baseline about how to prevent smoking relapse.

Measurements

The primary outcome is biochemically validated tobacco abstinence at 12 months after consent.

Comments

The findings will provide evidence concerning the utility of operating online social group discussion for prevention of smoking relapse and sustaining long‐term abstinence.
The influence of age and overweight or obesity on foot sensitivity and postural control: A systematic review
Authors: Andreato Leonardo Vidal , de Oliveira Daniel Vicentini , Follmer Bruno , Bertolini Sônia Maria Marques Gomes
Published: March 2020

Objective

To perform a systematic review on the influence of age and overweight—or obesity—on foot sensitivity, as well as its relationship with balance and postural control.

Methods

Publications in the following databases were searched up to December 2018: Cochrane Library, PubMed, Scopus, SPORTDiscus and Web of Science. Both randomised controlled and non‐randomised trials, plus cross‐sectional studies that evaluated foot sensitivity and balance in adults and/or older people, were investigated.

Results

A total of 152 studies were found, 14 studies were included and 506 people of both sexes were involved in the included studies.

Conclusions

Increased age represented a detrimental effect on foot sensitivity. Most studies showed that decreased foot sensitivity was related to worse balance and/or postural stability. Overweight or obesity was associated with plantar sensitivity, with lower sensitivity and decreased postural stability observed in obese people.
A ‘match–no match‘ numerical and graphical kernel density approach to interpreting lead isotope signatures of ancient artefacts
Authors: De Ceuster Sarah , Degryse Patrick
Published: March 2020

A new method for interpreting lead isotope ratios of artefacts is presented: a numerical and graphical ‘match–no match‘ with possible raw materials. By calculating the definite integral under the kernel density estimate plot of different mining districts, using open‐access software and legacy data, the relative probability that an object is made of an ore is indicated. A match with the reference data set may indicate the true origin, while no match indicates an unknown origin, that is, not present in the data set of mineral resources. Likewise, the composite or recycled nature of artefacts can be investigated in a probabilistic manner.
Predicting sediment discharges and erosion rates in deep time—examples from the late Cretaceous North American continent
Authors: Lyster Sinéad J. , Whittaker Alexander C. , Allison Peter A. , Lunt Daniel J. , Farnsworth Alexander
Published: February 2020

Depositional stratigraphy represents the only physical archive of palaeo‐sediment routing and this limits analysis of ancient source‐to‐sink systems in both space and time. Here, we use palaeo‐digital elevation models (palaeoDEMs; based on high‐resolution palaeogeographic reconstructions), HadCM3L general circulation model climate data and the BQART suspended sediment discharge model to demonstrate a predictive, forward approach to palaeo‐sediment routing system analysis. To exemplify our approach, we use palaeoDEMs and HadCM3L data to predict the configurations, geometries and climates of large continental catchments in the Cenomanian and Turonian North American continent. Then, we use BQART to estimate suspended sediment discharges and catchment‐averaged erosion rates and we map their spatial distributions. We validate our estimates with published geologic constraints from the Cenomanian Dunvegan Formation, Alberta, Canada, and the Turonian Ferron Sandstone, Utah, USA, and find that estimates are consistent or within a factor of two to three. We then evaluate the univariate and multivariate sensitivity of our estimates to a range of uncertainty margins on palaeogeographic and palaeoclimatic boundary conditions; large uncertainty margins (≤50%/±5°C) still recover estimates of suspended sediment discharge within an order of magnitude of published constraints. PalaeoDEMs are therefore suitable as a first‐order investigative tool in palaeo‐sediment routing system analysis and are particularly useful where stratigraphic records are incomplete. We highlight the potential of this approach to predict the global spatio‐temporal response of suspended sediment discharges and catchment‐averaged erosion rates to long‐period tectonic and climatic forcing in the geologic past.
Specific slow tests are not mandatory in patients with extremely short standard (3.2 km/hr 10% slope) test durations during exercise oximetry
Authors: Sempore Wendsèndaté Yves , Ramondou Pierre , Hersant Jeanne , Feuilloy Mathieu , Guilleron Celine , Henni Samir , Abraham Pierre
Published: February 2020

Aim

To compare the transcutaneous oxygen pressure results observed in patients with severe walking limitation during standard procedures (3.2 km/hr, 10% slope) versus during a test performed at a low speed (2 km/hr, 10% slope).

Methods

In 31 patients, the decrease from rest of oxygen pressure (DROP) index was measured on both buttocks, both thighs and both calves during two consecutive tests on treadmill. The maximal walking time (MWT) and the minimal DROP values (DROPmin) observed during the 2 tests were compared with t test. Correlation of DROPmin values during the slow and standard procedure was performed with linear regression. The −15 mmHg cut‐off value defined for standard test interpretation was used arbitrarily for the interpretation of slow test results.

Results

MWT was 80 ± 52 s versus 376 ± 269 s at standard and slow speed, respectively (p < .001). No difference on all recorded DROPmin values at a standard (−9.5 ± 6.9 mmHg) and slow (−10.5 ± 7.9 mmHg) speed was found; n = 186, p = .168. Coefficient of correlation between DROPmins found at the two tests was r = 0.820 (p < .01), with regression line close to the line of identity. With the identical −15 mmHg cut‐off, 166 (89.2%) of 186 the results were classified similarly after standard and slow procedures.

Conclusion

Specific slow treadmill procedures are not mandatory in patients with extremely short test durations when performing standard (3.2 km/hr 10% slope) exercise oximetry. In patients expected to be unable to walk at standard speed, the −15 mmHg normal limit seems to be valid for the interpretation of tests with a slow procedure (2.0 km/hr).