bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling reveals cortical dynein-dependent fluctuations in bipolar spindle length
Authors: Mercadante Dayna L. , Manning Amity L. , Olson Sarah D.
Published: July 2020

Proper formation and maintenance of the mitotic spindle is required for faithful cell division. While much work has been done to understand the roles of the key molecular components of the mitotic spindle, identifying the consequences of force perturbations in the spindle remains a challenge. We develop a computational framework accounting for the minimal force requirements of mitotic progression. To reflect early spindle formation, we model microtubule dynamics and interactions with major force-generating motors, excluding chromosome interactions that dominate later in mitosis. We directly integrate our experimental data to define and validate the model. We then use simulations to analyze individual force components over time and their relationship to spindle dynamics, making it distinct from previously published models. We show through both model predictions and biological manipulation that rather than achieving and maintaining a constant bipolar spindle length, fluctuations in pole to pole distance occur that coincide with microtubule binding and force generation by cortical dynein. Our model further predicts that high dynein activity is required for spindle bipolarity when kinesin-14 (HSET) activity is also high. Together, our results provide novel insight into the role of cortical dynein in the regulation of spindle bipolarity.

SIGNIFICANCE

The mitotic spindle is a biophysical machine that is required for cell division. Here we have paired a modeling approach with experimental data to understand the maintenance and dynamics of a bipolar mitotic spindle in the absence of chromosome interactions. We present novel roles of cortical dynein in mitosis, and demonstrate its requirement for both dynamic changes in spindle length and in antagonizing HSET in bipolar spindle formation. Model outputs predict that cortical dynein activity would be limiting in contexts where HSET activity is high and may be of therapeutic relevance in cancer contexts where HSET is often over expressed.
SARS-CoV-2 induces human plasmacytoid pre-dendritic cell diversification via UNC93B and IRAK4
Authors: Onodi Fanny , Bonnet-Madin Lucie , Meertens Laurent , Karpf Léa , Poirot Justine , Zhang Shen-Ying , Picard Capucine , Puel Anne , Jouanguy Emmanuelle , Zhang Qian , Le Goff Jérôme , Molina Jean-Michel , Delaugerre Constance , Casanova Jean-Laurent , Amara Ali , Soumelis Vassili
Published: July 2020

Several studies have analyzed antiviral immune pathways in late-stage severe COVID-19. However, the initial steps of SARS-CoV-2 antiviral immunity are poorly understood. Here, we have isolated primary SARS-CoV-2 viral strains, and studied their interaction with human plasmacytoid pre-dendritic cells (pDC), a key player in antiviral immunity. We show that pDC are not productively infected by SARS-CoV-2. However, they efficiently diversified into activated P1-, P2-, and P3-pDC effector subsets in response to viral stimulation. They expressed CD80, CD86, CCR7, and OX40 ligand at levels similar to influenza virus-induced activation. They rapidly produced high levels of interferon-α, interferon-λ1, IL-6, IP-10, and IL-8. All major aspects of SARS-CoV-2-induced pDC activation were inhibited by hydroxychloroquine. Mechanistically, SARS-CoV-2-induced pDC activation critically depended on IRAK4 and UNC93B1, as established using pDC from genetically deficient patients. Overall, our data indicate that human pDC are efficiently activated by SARS-CoV-2 particles and may thus contribute to type I IFN-dependent immunity against SARS-CoV-2 infection.
Kindlin2-mediated phase separation underlies integrin adhesion formation
Authors: Li Yujie , Zhang Ting , Li Huadong , Yang Haibin , Lin Ruihong , Sun Kang , Wang Lei , Zhang Jing , Wei Zhiyi , Yu Cong
Published: July 2020

Formation of cell-extracellular matrix adhesion requires assembly of the transmembrane receptor integrins and their intracellular activators, kindlin and talin proteins in minutes. The mechanisms governing the rapid formation and dynamics of the adhesion remain enigmatic. Here, we reported that the dimerized-kindlin2 underwent phase separation with clustered-integrin in solution and on lipid bilayer. The kindlin2/integrin condensate can further enrich other components for the adhesion complex assembly. The full-length structure of kindlin2 was solved and revealed that the kindlin2 dimers can further pack with each other to form a higher oligomer. Disrupting the intermolecular interaction between the kindlin2 dimer inhibits the phase formation on 2D membrane in vitro and impaired the adhesion formation, integrin activation, and cell spreading in cultured cells. We also determined the full-length structure of kindlin2 in its monomeric conformation. Structural analysis and biochemical characterization indicate that the interdomain interaction control the monomer-dimer transition of kindlin2, providing a regulation mechanism of the kindlin2-mediated phase separation. Our findings not only provide a mechanistic explanation for the formation and dynamic regulation of the integrin-based adhesion, but also shed light on understanding of how the clustered receptors participate in assembly of the functional membrane domains via phase separation.
Identification of parallel pH- and zeaxanthin-dependent quenching of excess energy in LHCSR3 in Chlamydomonas reinhardtii
Authors: Troiano Julianne M. , Perozeni Federico , Moya Raymundo , Zuliani Luca , Baek Kwangryul , Jin EonSeon , Cazzaniga Stefano , Ballottari Matteo , Schlau-Cohen Gabriela S.
Published: July 2020

Under high light conditions, oxygenic photosynthetic organisms avoid photodamage by thermally dissipating excess absorbed energy, which is called non-photochemical quenching (NPQ). In green algae, a chlorophyll and carotenoid-binding protein, light-harvesting complex stress-related (LHCSR3), detects excess energy via pH and serves as a quenching site. However, the mechanisms by which LHCSR3 functions have not been determined. Using a combined in vivo and in vitro approach, we identify two parallel yet distinct quenching processes, individually controlled by pH and carotenoid composition, and their likely molecular origin within LHCSR3 from Chlamydomonas reinhardtii. The pH-controlled quenching is removed within a mutant LHCSR3 that lacks the protonable residues responsible for sensing pH. Constitutive quenching in zeaxanthin-enriched systems demonstrates zeaxanthin-controlled quenching, which may be shared with other light-harvesting complexes. We show that both quenching processes prevent the formation of damaging reactive oxygen species, and thus provide distinct timescales and mechanisms of protection in a changing environment.
Allosteric modulation of GABAAreceptors in rat basolateral amygdala blocks stress-enhanced reacquisition of nicotine self-administration
Authors: Sharp Burt M , Jiang Qin , Simone Xenia , Scholze Petra
Published: July 2020

Stress is a major determinant of relapse to smoked tobacco. In a rat model, repeated stress during abstinence from nicotine self-administration (SA) results in enhanced reacquisition of nicotine SA, which is dependent on the basolateral amygdala (BLA). We postulate that repeated stress during abstinence causes hyperexcitability of BLA principal output neurons (PN) due to disinhibition of PN from reduced inhibitory regulation by local GABAergic interneurons. To determine if enhanced GABAergic regulation of BLA PNs can lessen the effects of stress on nicotine intake, positive allosteric modulators (PAMs) of GABAAreceptors were infused into the BLA immediately prior to reacquisition of nicotine SA. Three selective PAMs (e.g., NS 16085, DCUK-OEt, DS2) with varied GABAAsubunit specificities abolished the stress-induced amplification of nicotine taking during reacquisition. These studies indicate that highly selective PAMS targeting α3 or δ subunit-containing GABAAin BLA may be effective in ameliorating the stress-induced relapse to smoked tobacco during abstinence from cigarettes.
Improved characterisation of clinical text through ontology-based vocabulary expansion
Authors: Slater Luke T , Bradlow William , Ball Simon , Hoehndorf Robert , Gkoutos Georgios V
Published: July 2020

Background

Biomedical ontologies contain a wealth of metadata that constitutes a fundamental infrastructural resource for text mining. For several reasons, redundancies exist in the ontology ecosystem, which lead to the same concepts being described by several terms in the same or similar contexts across several ontologies. While these terms describe the same concepts, they contain different sets of complementary metadata. Linking these definitions to make use of their combined metadata could lead to improved performance in ontology-based information retrieval, extraction, and analysis tasks.

Results

We develop and present an algorithm that expands the set of labels associated with an ontology class using a combination of strict lexical matching and cross-ontology reasoner-enabled equivalency queries. Across all disease terms in the Disease Ontology, the approach found51,362additional labels, more than tripling the number defined by the ontology itself. Manual validation by a clinical expert on a random sampling of expanded synonyms over the Human Phenotype Ontology yielded a precision of0.912. Furthermore, we found that annotating patient visits in MIMIC-III with an extended set of Disease Ontology labels led to semantic similarity score derived from those labels being a significantly better predictor of matching first diagnosis, with a mean average precision of0.88for the unexpanded set of annotations, and0.913for the expanded set.

Conclusions

Inter-ontology synonym expansion can lead to a vast increase in the scale of vocabulary available for text mining applications. While the accuracy of the extended vocabulary is not perfect, it nevertheless led to a significantly improved ontology-based characterisation of patients from text in one setting. Furthermore, where run-on error is not acceptable, the technique can be used to provide candidate synonyms which can be checked by a domain expert.
Somatotopic specificity of perceptual and neurophysiological changes associated with visuo-proprioceptive realignment
Authors: Mirdamadi Jasmine L. , Seigel Courtney R. , Husch Stephen D. , Block Hannah J.
Published: July 2020

Spatial realignment of visual and proprioceptive estimates of hand position can occur in response to a perturbation. E.g., viewing the hand underwater while washing dishes. This form of multisensory perceptual learning presumably affects perceived hand position, which is used in movement planning. Consistent with this idea, we recently observed changes in motor cortex (M1) index finger representation associated with visuo-proprioceptive misalignment at that fingertip (Munoz-Rubke et al., 2017). In three experiments with healthy human participants, we asked whether these changes are specific to the brain’s representation of the misaligned finger (somatotopically focal), or whether they extend to other parts of the hand and arm that would be needed to move the misaligned finger (somatotopically broad). In Experiments 1 and 2, participants experienced misaligned or veridical visuo-proprioceptive information about the index fingertip. Before and after the perceptual alignment task, we used transcranial magnetic stimulation (TMS) to assess M1 representation of five hand and arm muscles. The index finger representation showed the expected association between M1 excitability and visuo-proprioceptive realignment, as did the pinkie finger representation to a lesser extent. Forearm flexors, forearm extensors, and biceps did not show any such relationship. In Experiment 3, we asked subjects to indicate their proprioceptive estimate of the fingertip, knuckle, wrist, and elbow, before and after misalignment at the fingertip. Proprioceptive realignment at the knuckle, but not the wrist or elbow, was correlated with realignment at the fingertip. These results suggest the effects of perceptual perturbation are somatotopically focal in both sensory and motor domains.

Significance Statement

Multisensory and motor processing have largely been examined separately, limiting our understanding of how these systems interact. Motor adaptation is thought to affect somatosensory perception and neurophysiology, but the reverse interaction, an effect of perceptual learning on the motor system, has rarely been considered. Here we examine the effect of a somatotopically localized visuo-proprioceptive perturbation on motor neurophysiology and conscious perception. We found somatotopically-focal effects in both domains. This correspondence highlights the tight relationship between sensory and motor systems, but also raises the possibility that perceptual learning may not generalize to other body parts as motor learning does. Rather, it appears to create a localized distortion in the multisensory body representation, with correspondingly local changes in the motor cortex representation.
Visualization of Collagen–Mineral Arrangement using Atom Probe Tomography
Authors: Lee Bryan E.J. , Langelier Brian , Grandfield Kathryn
Published: July 2020

Bone is a complex, hierarchical structure comprised of two distinct phases: the organic, collagen– rich phase and the inorganic mineral–rich phase. This collagen–mineral arrangement has implications for bone function, aging, and disease. However, strategies to extract a single mineralized collagen fibril to investigate the interplay between components with sufficient resolution have been mostly confined toin vitrosystems that only approximate the biological environment or transmission electron microscopy studies with lower spatial and chemical resolution. Therefore, there is extensive debate over the location of mineral with respect to collagen inin vivomineralized tissues as visualization and quantification of the mineral in a living system is difficult or impossible. Herein, we have developed an approach to artificially extract a single mineralized collagen fibril from bone to analyze its composition and structure atom-by-atom with 3D resolution and sub-nanometer accuracy using atom probe tomography. This enables, for the first time, a method to probe fibril-level mineralization and collagen–mineral arrangement from anin vivosystem with both the spatial and chemical precision required to comment on collagen– mineral arrangement. Using atom probe tomography, 4D (spatial + chemical) reconstructed volumes of leporine bone were generated with accuracy from correlative scanning electron microscopy. Distinct, winding collagen fibrils were identified with mineralized deposits both encapsulating and incorporated into the collagenous structures. This work demonstrates a novel fibril-level detection method that can be used to probe structural and chemical changes of bone and contribute new insights to the debate on collagen–mineral arrangement in mineralized tissues such as bones, and teeth.
Extensive hybridization reveals multiple coloration genes underlying a complex plumage phenotype
Authors: Aguillon Stepfanie M. , Walsh Jennifer , Lovette Irby J.
Published: July 2020

Coloration is an important target of both natural and sexual selection. Discovering the genetic basis of color differences can help us to understand how this visually striking phenotype evolves. Hybridizing taxa with both clear color differences and shallow genomic divergences are unusually tractable for associating coloration phenotypes with their causal genotypes. Here, we leverage the extensive admixture between two common North American woodpeckers—yellow-shafted and red-shafted flickers—to identify the genomic bases of six distinct plumage patches involving both melanin and carotenoid pigments. Comparisons between flickers across ~8.5 million genome-wide SNPs show that these two forms differ at only a small proportion of the genome (meanFST= 0.007). Within the few highly differentiated genomic regions, we identify 408 SNPs significantly associated with four of the six plumage patches. These SNPs are linked to multiple genes known to be involved in melanin and carotenoid pigmentation. For example, a gene (CYP2J19) known to cause yellow to red color transitions in other birds is strongly associated with the yellow versus red differences in the wings and tail feathers of these flickers. Additionally, our analyses suggest novel links between known melanin genes and carotenoid coloration. Our finding of patch-specific control of plumage coloration adds to the growing body of literature suggesting color diversity in animals could be created through selection acting on novel combinations of coloration genes.
Plate reader microrheology
Authors: Hawkins Robert F. , Duncan Gregg A.
Published: July 2020

In this work, we report the development of a simplified microrheological method that can be used to rapidly study soft materials. This approach uses fluorescence polarization and a plate reader format to measure the rotational diffusion of nanoparticles within a sample of interest. We show that this measurement is sensitive to viscosity-dependent changes in polymeric soft materials and is correlated with particle tracking microrheology, a previously validated measure of microrheology. Using these fluorescence polarization-based measurements, we describe formalism that enables reasonable estimation of viscosity in polymeric materials after accounting for length-scale dependent effects of the polymer environment on the nanoparticle rotational diffusion. The use of a plate reader format allows this approach to be higher throughput, less technically challenging, and more widely accessible than standard macro- and microrheological methods, making it available to non-experts. This approach has potential applications in academic and industry settings where conventional rheological equipment may not be available, as well as in clinical settings to rapidly characterize human clinical samples.
InpherNet provides attractive monogenic disease gene hypotheses using patient genes indirect neighbors
Authors: Yoo Boyoung , Birgmeier Johannes , Bernstein Jonathan A. , Bejerano Gill
Published: July 2020

Close to 70% of patients suspected to have a Mendelian disease remain undiagnosed after genome sequencing, partly because our current knowledge about disease-causing genes is incomplete. Although hundreds of new diseases-causing genes are discovered every year, the discovery rate has been constant for over a decade. Generating an attractive novel disease gene hypothesis from patient data can be time-consuming as each patient’s genome can contain dozens to hundreds of rare, possibly pathogenic variants. To generate the most plausible hypothesis, many sources of indirect evidence about each candidate variant may be considered. We introduce InpherNet, a network-based machine learning approach to accelerate this process. InpherNet ranks candidate genes based on gene neighbors from 4 graphs, of orthologs, paralogs, functional pathway members, and co-localized interaction partners. As such InpherNet can be used to both prioritize potentially novel disease genes and also help reveal known disease genes where their direct annotation is missing, or partial. InpherNet is applied to over 100 patient cases for whom the causative gene is incorrectly given low priority by two clinical gene ranking methods that rely exclusively on human patient-derived evidence. It correctly ranks the causative gene among its top 5 candidates in 68% of the cases, compared to 9-44% using comparable tools including Phevor, Phive and hiPhive.
Community prevalence of SARS-CoV-2 virus in England during May 2020: REACT study
Authors:   REACT Study Investigators, Riley Steven , Ainslie Kylie E. C. , Eales Oliver , Jeffrey Benjamin , Walters Caroline E. , Atchison Christina , Diggle Peter J. , Ashby Deborah , Donnelly Christl A. , Cooke Graham , Barclay Wendy , Ward Helen , Taylor Graham , Darzi Ara , Elliott Paul
Published: July 2020

Background

England has experienced one of the highest rates of confirmed COVID-19 mortality in the world. SARS-CoV-2 virus has circulated in hospitals, care homes and the community since January 2020. Our current epidemiological knowledge is largely informed by clinical cases with far less understanding of community transmission.

Methods

The REal-time Assessment of Community Transmission (REACT) study is a nationally representative prevalence survey of SARS-CoV-2 virus swab-positivity in the community in England. We recruited participants regardless of symptom status.

Results

We found 159 positives from 120,610 swabs giving an average prevalence of 0.13% (95% CI: 0.11%,0.15%) from 1st May to 1st June 2020. We showed decreasing prevalence with a halving time of 8.6 (6.2, 13.6) days, implying an overall reproduction number R of 0.57 (0.45, 0.72). Adults aged 18 to 24 yrs had the highest swab-positivity rates, while those >64 yrs had the lowest. Of the 126 participants who tested positive with known symptom status in the week prior to their swab, 39 reported symptoms while 87 did not, giving an estimate that 69% (61%,76%) of people were symptom-free for the 7 days prior testing positive in our community sample. Symptoms strongly associated with swab-positivity were: nausea and/or vomiting, diarrhoea, blocked nose, loss of smell, loss of taste, headache, chills and severe fatigue. Recent contact with a known COVID-19 case was associated with odds of 24 (16, 38) for swab-positivity. Compared with non-key workers, odds of swab-positivity were 7.7 (2.4, 25) among care home (long-term care facilities) workers and 5.2 (2.9, 9.3) among health care workers. However, some of the excess risk associated with key worker status was explained by recent contact with COVID-19 cases. We found no strong evidence for geographical variability in positive swab results.

Conclusion

Our results provide a reliable baseline against which the impact of subsequent relaxation of lockdown can be assessed to inform future public health efforts to control transmission.
A neural network model for UAV propulsion system
Authors: Işık Gültekin , Ekici Selçuk , Şahin Gökhan
Published: July 2020

Purpose

Determining the performance parameters of the propulsion systems of the aircraft, which is the key product of the aviation industry, plays a critical role in reducing adverse environmental impacts. Therefore, the purpose of this paper is to present a temperature performance template for turbojet engines at the design stage using a neural network model that defines the relationship between the performance parameters obtained from ground tests of a turbojet engine used in unmanned aerial vehicles (UAV).

Design/methodology/approach

The main parameters of the flow passing through the engine of the UAV propulsion system, where ground tests were performed, were obtained through the data acquisition system and injected into a neural network model created. Fifteen sensors were mounted on the engine – six temperature sensors, six pressure sensors, two flow meters and one load cell were connected to the data acquisition system to make sense of this physical environment. Subsequently, the artificial neural network (ANN) model as a complement to the approach was used. Thus, the predicted model relationship with the experimental data was created.

Findings

Fuel flow and thrust parameters were estimated using these components as inputs in the feed-forward neural network. In the network experiments to estimate fuel flow parameter, r-square and mean absolute error were calculated as 0.994 and 0.02, respectively. Similarly, for thrust parameter, these metrics were calculated as 0.994 and 1.42, respectively. In addition, the correlation between fuel flow, thrust parameters and each input parameters was examined. According to this, air compressor inlet (ACinlet,temp) and outlet (ACoutlet,temp) temperatures and combustion chamber (CCinlet,temp, CCoutlet,temp) temperature parameters were determined to affect the output the most. The proposed ANN model is applicable to any turbojet engines to model its behavior.

Practical implications

Today, deep neural networks are the driving force of artificial intelligence studies. In this study, the behavior of a UAV is modeled with neural networks. Neural networks are used here as a regressor. A neural network model has been developed that predicts fuel flow and thrust parameters using the real parameters of a UAV turbojet engine. As a result, satisfactory findings were obtained. In this regard, fuel flow and thrust values of any turbojet engine can be estimated using the neural network hyperparameters proposed in this study. Python codes of the study can be accessed from https://github.com/tekinonlayn/turbojet.

Originality/value

The originality of the study is that it reports the relationships between turbojet engine performance parameters obtained from ground tests using the neural network application with open source Python code. Thus, small-scale unmanned aerial propulsion system provides designers with a template showing the relationship between engine performance parameters.
The role of technology readiness in individuals' intention to use health and fitness applications: a comparison between users and non-users
Authors: Chiu Weisheng , Cho Heetae
Published: July 2020

Purpose

The purpose of this study is to examine individuals' decisions to use health and fitness apps by applying the extended technology readiness and acceptance model (TRAM), which combines technology readiness (TR), the technology acceptance model (TAM) and perceived enjoyment (PEN). Moreover, this study explores the differences between users and non-users regarding their intentions to use health and fitness apps.

Design/methodology/approach

Data collection (n = 206) was conducted using convenience sampling from four large universities in South Korea. The data were analysed by partial least squares structural equation modelling (PLS-SEM) using SmartPLS 3.0.

Findings

The results revealed that positive TR positively affects perceived ease of use (PEOU), perceived usefulness (PU) and PEN, while negative TR had a negative impact only on PEN. Furthermore, the significant relationships between PEOU, PU and PEN were identified. In addition, multigroup analyses indicated that the relationships between positive TR and PEN, between PEN and PEOU, between PEOU and PU, and between PU and behavioural intention were positively stronger for app users.

Originality/value

This study initially applied the TRAM to understand individuals' behavioural intentions to use health and fitness apps. Moreover, this study identified the distinct roles of positive and negative TR affecting individuals' cognition regarding using health and fitness apps. The differences in the psychological processes between app users and non-users offer insights and implications for practitioners.
Optimal resource allocation and prolonged dormancy strategies in herbaceous plants
Authors: Watts J. Colton , Tenhumberg Brigitte
Published: July 2020

Understanding the fitness consequences of different life histories is critical for explaining their diversity and for predicting effects of changing environmental conditions. However, current theory on plant life histories relies on phenomenological, rather than mechanistic, models of resource production.

We combined a well‐supported mechanistic model of ontogenetic growth that incorporates differences in the size‐dependent scaling of gross resource production and maintenance costs with a dynamic optimization model to predict schedules of reproduction and prolonged dormancy (plants staying below ground for ≥1 growing season) that maximize lifetime offspring production.

Our model makes three novel predictions: First, maintenance costs strongly influence the conditions under which a monocarpic or polycarpic life history evolves and how resources should be allocated to reproduction by polycarpic plants. Second, in contrast to previous theory, our model allows plants to compensate for low survival conditions by allocating a larger proportion of resources to storage and thereby improving overwinter survival. Incorporating this ecological mechanism in the model is critically important because without it our model never predicts significant investment into storage, which is inconsistent with empirical observations. Third, our model predicts that prolonged dormancy may evolve solely in response to resource allocation trade‐offs.

Significance. Our findings reveal that maintenance costs and the effects of resource allocation on survival are primary determinants of the fitness consequences of different life history strategies, yet previous theory on plant life history evolution has largely ignored these factors. Our findings also validate recent arguments that prolonged dormancy may be an optimal response to costs of sprouting. These findings have broad implications for understanding patterns of plant life history variation and predicting plant responses to changing environments.
Plant protection services mediated by extrafloral nectaries decline with aridity but are not influenced by chronic anthropogenic disturbance in Brazilian Caatinga
Authors: Oliveira Fernanda M. P. , Câmara Talita , Durval José I. F. , Oliveira Caroline L. S. , Arnan Xavier , Andersen Alan N. , Ribeiro Elâine M. S. , Leal Inara R.
Published: July 2020

Most terrestrial species occur in human‐modified landscapes that are experiencing climate change. In addition to direct impacts on species, both anthropogenic disturbance and climate change can have important effects through changes in species interactions, including the disruption of ecological services provided by them.

Here we investigate how chronic anthropogenic disturbance (CAD) and aridity affect the effectiveness of plant protection services provided by ants to plants bearing extrafloral nectaries (EFNs).

The study was conducted across 13 01‐ha plots distributed along CAD and aridity gradients in Caatinga vegetation of northeastern Brazil. We focused on Pityrocarpa moniliformis, the most abundant and widely distributed EFN‐bearing tree species occurring in our study area, and we used experimental attack rates on termites as a measure of effectiveness of ant protection services. We investigated the relative roles of nectar production (volume and concentration) and ant species composition in mediating the effects of CAD and aridity on the effectiveness of protection services.

Attack rates by ants declined with increasing aridity but were not related to CAD. The volume of extrafloral nectar declined with increasing CAD but was not affected by aridity, whereas the concentration was not related to either CAD or aridity. The composition of attendant ant species varied with aridity but not with CAD.

Synthesis. Our findings suggest that CAD does not affect plant‐protection services mediated by EFNs in Brazilian Caatinga. However, ant‐protection services declined with increased aridity, and this occurred through changes in the composition of attendant ant species rather than by changes in the production of extrafloral nectar. Such a response to increasing aridity highlights the vulnerability of EFN‐bearing plants to climate change through decreased predation of herbivores.
New dynamics of multinational migration: Chinese and Indian migrants in Singapore and Los Angeles
Authors: Zhan Shaohua , Aricat Rajiv , Zhou Min
Published: July 2020

The emerging literature on multinational migration highlights migratory journeys that involve more than one country of destination. This article focuses on the lived experiences of new Chinese and Indian migrants in Singapore and Los Angeles. We conduct a novel three‐way comparison to examine personal choices to engage in additional migration(s) and to consider the reasons behind such moves. Drawing on in‐depth interviews and analyses of policy documents, we find that new, especially skilled, migrants from China and India actively participate in multinational migration. However, variations exist between these two national origin groups and between the two global cities. Factors affecting decisions about whether and where to further migrate include immigration policy of the host country, job opportunities, homeland economic development, and migration networks. Singapore regulates migrants' long‐term settlement more tightly than does the United States; thus, migrants in the former are more likely than the latter to move onward to another country. Due to a more robust economy in the homeland, Chinese migrants are more likely to return and are thus less likely to migrate to a third country than their Indian counterparts. Job opportunities and migration networks also have strong effects on personal decisions concerning additional migration(s).
Use of olive (Olea europaea L.) leaves as beer ingredient, and their influence on beer chemical composition and antioxidant activity
Authors: Guglielmotti Manfredi , Passaghe Paolo , Buiatti Stefano
Published: July 2020

Olive leaves are well known for their high polyphenol content and beneficial effects to human health. The two main phenolic compounds of olive leaves are oleuropein and 3‐hydroxytyrosol. Use of olive leaves as beer ingredient was evaluated, to investigate their contribution to bitterness and antioxidant activity of beer. Thirteen beer samples were produced, adding olive leaves during boiling at different boiling times, in different forms and concentrations. Three different forms were used: dry crumbled leaves, infusion, and atomized extract. The effects of olive leaves addition were evaluated through following analysis: total polyphenols content, oleuropein and 3‐hydroxytyrosol content, antioxidant capacity, sensory analysis, shelf‐life prediction. Results confirmed that addition of olive leaves highly increased polyphenol content of beers. Boiling time favored hydrolysis of oleuropein to 3‐hydroxytyrosol. Antioxidant activity was not influenced by addition of olive leaves. Higher polyphenol content of beer samples increased colloidal instability of beer. Sensory analysis results demonstrated that about 10 g/L of olive leaves imparts a sour/astringent taste and herbal aroma. A lower quantity of olive leaves (about 5 g/L) allowed to obtain a beer with a pleasant sensory profile.

Practical Application

Our research was inspired by both the high interest in alternative ingredients able to add nutraceutical value to traditional food, and by the growing craft beer market, with its constant research for innovative and characterizing ingredients. This project has several aims: evaluate if olive leaves could partially substitute hops in beer bittering (reducing costs); if their addition increase beer polyphenol content; which amount and using technique gives the best results in terms of polyphenol extraction and sensory profile; how this addition influence beer stability. This work could then encourage new research about the nutraceutical value of this new type of beer.
Effects of brew strength, brew yield, and roast on the sensory quality of drip brewed coffee
Authors: Frost Scott C. , Ristenpart William D. , Guinard Jean‐Xavier
Published: July 2020

Drip brewed coffee is traditionally quantified in terms of its strength, also known as total dissolved solids (TDS), and its brewing yield, also known as percent extraction (PE). Early work in the 1950s yielded classifications of certain regimes of TDS and PE as “underdeveloped,” “bitter,” or “ideal,” with the modifiers “weak” or “strong” simply correlated with TDS. Although this standard is still widely used today, it omits a rich variety of sensory attributes perceptible in coffee. In this work, we used response surface methodology to evaluate the influence of TDS and PE on the sensory profile of drip brewed coffee. A representative wet‐washed Arabica coffee was roasted to three different levels (light, medium, or dark), with each roast then brewed to nine target brews that varied systematically by TDS and PE. Descriptive analysis found that 21 of the 30 evaluated attributes differed significantly across the brews for one or more experimental factors, yielding linear or second‐order response surfaces versus TDS and PE. Seven attributes exhibited a significant response surface for all three roast levels tested: burnt wood/ash flavor, citrus flavor, sourness, bitterness, sweetness, thickness, and flavor persistence. An additional seven attributes also showed a significant response surface fit across some but not all roasts. Importantly, sweetness exhibited an inverse correlation with TDS irrespective of roast, while dark chocolate flavor and blueberry flavor decreased with TDS for medium roast. These results provide new insight on how to optimize brewing conditions to achieve desired sensory profiles in drip brewed coffee.

Practical Application

This research provides guidance on how best to achieve specific flavor profiles in drip brewed coffee.
The effect of stock liquidity on investment efficiency under financing constraints and asymmetric information: Evidence from the United States
Authors: Quah Heidi , Haman Janto , Naidu Dharmendra
Published: July 2020

We examine whether the association between stock liquidity and investment efficiency is more pronounced for firms with more financial constraints and information asymmetry problems. The results show that the effect of higher stock liquidity on lowering under (over)‐investment is more pronounced for firms with more financial constraints and information asymmetry problems as proxied by younger and higher business risk firms, respectively. We also find similar results for firms with lower institutional ownership, more external financing dependence and higher idiosyncratic risks. The findings collectively suggest that the effect of stock liquidity in our setting is more pervasive for firms with more financial constraints and information asymmetry problems.
Do ETF flows increase market efficiency? Evidence from China
Authors: Chen Jilong , Xu Liao , Zhao Yang
Published: July 2020

Focusing on the equity exchange traded funds (ETFs) in China, we demonstrate the significant effect of ETF flows on the informativeness of the ETF index. Following the novel approach proposed by Xu et al (2019a). to identify different driving forces for ETF flows, we explore whether the forward‐looking ETF flows at a day’s closing substantially improve the index’s efficiency on the next day. The mechanism behind it is inter‐market information spread: the efficiency effect of the forward‐looking ETF flows strengthens when ETFs share more new information; and the forward‐looking ETF flows increase the information flow to the ETF index on the next day.
Response of female black bears to a high‐density road network and identification of long‐term road mitigation sites
Authors: Zeller K. A. , Wattles D. W. , Conlee L. , Destefano S.
Published: July 2020

Roads can result in negative effects on wildlife including habitat loss, behavioral avoidance, reduced survival, reproduction and gene flow. These road effects are especially pronounced for large mammals given their large home‐range requirements and low reproductive rates. To counteract these negative effects, road mitigation measures, such as underpasses and overpasses, are promoted; however, future landscape changes are rarely considered when selecting mitigation locations. We used GPS telemetry data on female American black bears Ursus americanus to examine their response to roads in Massachusetts, US. We compared bear road crossing frequency with a null crossing model derived from a correlated random walk, estimated road crossing movement speeds, and fit a road‐crossing resource selection function. We found that, though black bears crossed roads less than expected based on the null model, 10% of their observed steps, on average, crossed roads. We also found bears crossed roads at higher movement speeds than during other home‐range behaviors, and that bears preferred to cross smaller, less trafficked roads in areas with lower speed limits, less human development and more forest. We used the resource selection model to identify road segments for potential mitigation efforts and then used future human development projections to forecast future changes in these segments. We found a decrease of 15% in the length of suitable mitigation segments from 2019 to 2050. Given the sizeable investment in wildlife crossing structures and their longevity on the landscape, we recommend incorporating future projections into crossing site selection to ensure the long‐term viability of road mitigation efforts.
Spatial distribution of aphids in the canopy of a temperate forest: where can they be found?
Authors: Platková Hana , Pyszko Petr , Coeur d´Acier Armelle , Jousselin Emmanuelle , Drozd Pavel
Published: July 2020

Temperate forest canopies support a high diversity of insects, but in comparison to the tropics, little is known about insect spatial distribution, particularly in terms of vertical stratification.

We used an aerial lift platform to sample a temperate floodplain forest canopy during two seasons. We aimed to describe patterns of aphid density and diversity in terms of vertical canopy stratification within a 0.2 ha forest plot.

Vertical gradient affected both the density and diversity of aphids. There was no general pattern in aphid distribution that applied to the eight tree species included in our survey. The aphid taxocoenosis was stratified differently on particular tree species and changed during the season.

Species composition was better explained by aboveground absolute position (in m), while aphid density was better explained by relative height in the tree (position in the crown). Considering that these factors were significant but that the same statistical models excluding any influence of relative or absolute position provided more robust explanations, we concluded that aphid spatial distribution in temperate forests is difficult to simplify. This likely depends on environmental factors, such as wind direction and strength, that affect aphid flight and landing.
Severe acute respiratory syndrome coronavirus 2 infection risk during elective peri‐operative care: a narrative review
Authors: Schutzer‐Weissmann J. , Magee D. J. , Farquhar‐Smith P.
Published: July 2020

The protection of healthcare workers from the risk of nosocomial severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection is a paramount concern. SARS‐CoV‐2 is likely to remain endemic and measures to protect healthcare workers against nosocomial infection will need to be maintained. This review aims to inform the assessment and management of the risk of SARS‐CoV‐2 transmission to healthcare workers involved in elective peri‐operative care. In the absence of data specifically related to the risk of SARS‐CoV‐2 transmission in the peri‐operative setting, we explore the evidence‐base that exists regarding modes of viral transmission, historical evidence for the risk associated with aerosol‐generating procedures and contemporaneous data from the COVID‐19 pandemic. We identify a significant lack of data regarding the risk of transmission in the management of elective surgical patients, highlighting the urgent need for further research.
A study on health and hygiene needs, strategies, and well‐being of an Aeta indigenous community in the Philippines through photovoice methods
Authors: Yang Eun‐Mi , Kim Jwakyum , Biag Al , Mangulabnan Jefferson , Dela Cruz Arlan , Sarmiento Philip Joseph
Published: July 2020

On a global scale, poor access to health and social welfare services for indigenous populations has threatened their overall well‐being, especially those living in remote or peripheral areas. Academics from two higher education institutions in South Korea and the Philippines conducted a community‐based research in an indigenous Aeta community in the highlands of Pampanga Province in the Philippines’ Central Luzon region. Using a photovoice method and community survey, they investigated family health and hygiene as well as the current strategies this indigenous community employs to address their concerns. Results revealed that the community lacks the basic human needs and services such as water, food, shelter, education, and health service. They demonstrated, however, resilience in managing their lives by making use of the available natural resources and by drawing strength from community spirit. This study provided insights on how higher education institutions and other concerned agencies craft initiatives intended to benefit vulnerable populations and underserved communities such as the indigenous peoples.
Metamizole but not ibuprofen reduces the plasma concentration of sertraline: Implications for the concurrent treatment of pain and depression/anxiety disorders
Authors: Gaebler Arnim Johannes , Schoretsanitis Georgios , Ben Omar Nagia , Haen Ekkehard , Endres Katharina , Hiemke Christoph , Paulzen Michael
Published: July 2020

Aim

Comorbidity of pain and depression or anxiety is a challenging clinical phenomenon, often requiring the concurrent application of antidepressant and analgesic drugs. Growing evidence suggests that the analgesic metamizole exhibits cytochrome P450 inducing properties. In the present study, we assessed the impact of metamizole and ibuprofen on plasma concentrations of the selective serotonin reuptake inhibitor sertraline.

Methods

Out of a therapeutic drug monitoring (TDM) database, three groups of patients were compared: patients receiving sertraline and metamizole (n = 15), patients receiving sertraline and ibuprofen (n = 19), and a matched control group without one of the analgesics (n = 19).

Results

Metamizole was associated with 67% lower median sertraline plasma concentrations compared to the control group (14 vs 42 ng/mL, P < 0.001). In contrast, differences between the ibuprofen group and the control group did not reach statistical significance (31 vs 42 ng/mL, P = 0.128). Moreover, the metamizole group demonstrated lower dose‐adjusted drug concentrations than the ibuprofen group (0.10 vs 0.26 (ng/mL)/(mg/day), P = 0.008). Finally, the metamizole group exhibited a higher proportion of patients whose sertraline concentrations were below the therapeutic reference range (40% in the metamizole group, 5% in the ibuprofen group, 0% in the control group, P = 0.005) indicating therapeutically insufficient drug concentrations.

Conclusion

Our findings support preliminary evidence that metamizole acts as a potent inductor of cytochrome P450 isoenzymes CYP2B6 and CYP3A4. We observed a clinically meaningful pharmacokinetic interaction between metamizole and sertraline, leading to insufficiently low sertraline drug concentrations. Clinicians should therefore consider alternative drug combinations or apply TDM‐guided dose adjustment of sertraline.