bluuebunny/crossref_metadata_2025 huggingface dataset:
Smaller hippocampal subfield volumes predict verbal associative memory in pediatric brain tumor survivors
Authors: Decker Alexandra L. , Szulc Kamila U. , Bouffet Eric , Laughlin Suzanne , Chakravarty M. Mallar , Skocic Jovanka , de Medeiros Cynthia B. , Mabbott Donald J.
Published: July 2017

The developing hippocampus is highly sensitive to chemotherapy and cranial radiation treatments for pediatric cancers, yet little is known about the effects that cancer treatents have on specific hippocampal subfields. Here, we examined hippocampal subfield volumes in 29 pediatric brain tumor survivors treated with cranial radiation and chemotherapy, and 30 healthy developing children and adolescents. We also examined associations between hippocampal subfield volumes and short‐term verbal memory. Hippocampal subfields (Cornus Ammonis (CA) 1, CA2‐3, dentate gyrus (DG)‐CA4, stratum radiatum—lacunosum—moleculare, and subiculum) were segmented using the Multiple Automatically Generated Templates for Different Brains automated segmentation algorithm. Neuropsychological assessment of short‐term verbal associative memory was performed in a subset of brain tumor survivors (N = 11) and typically developing children (N = 16), using the Children's Memory Scale or Wechsler's Memory Scale—third edition. Repeated measures analysis of variance showed that pediatric brain tumor survivors had significantly smaller DG‐CA4, CA1, CA2‐3, and stratum radiatum‐lacunosum‐moleculare volumes compared with typically developing children. Verbal memory performance was positively related to DG‐CA4, CA1, and stratum radiatum‐lacunosum‐moleculare volumes in pediatric brain tumor survivors. Unlike the brain tumor survivors, there were no associations between subfield volumes and memory in typically developing children and adolescents. These data suggest that specific subfields of the hippocampus may be vulnerable to brain cancer treatments, and may contribute to impaired episodic memory following brain cancer treatment in childhood.
Enhanced identification of a hydrologic model using streamflow and satellite water storage data: A multicriteria sensitivity analysis and optimization approach
Authors: Yassin Fuad , Razavi Saman , Wheater Howard , Sapriza‐Azuri Gonzalo , Davison Bruce , Pietroniro Alain
Published: July 2017

Hydrologic model development and calibration have continued in most cases to focus only on accurately reproducing streamflows. However, complex models, for example, the so‐called physically based models, possess large degrees of freedom that, if not constrained properly, may lead to poor model performance when used for prediction. We argue that constraining a model to represent streamflow, which is an integrated resultant of many factors across the watershed, is necessary but by no means sufficient to develop a high‐fidelity model. To address this problem, we develop a framework to utilize the Gravity Recovery and Climate Experiment's (GRACE) total water storage anomaly data as a supplement to streamflows for model calibration, in a multiobjective setting. The VARS method (Variogram Analysis of Response Surfaces) for global sensitivity analysis is used to understand the model behaviour with respect to streamflow and GRACE data, and the BORG multiobjective optimization method is applied for model calibration. Two subbasins of the Saskatchewan River Basin in Western Canada are used as a case study. Results show that the developed framework is superior to the conventional approach of calibration only to streamflows, even when multiple streamflow‐based error functions are simultaneously minimized. It is shown that a range of (possibly false) system trajectories in state variable space can lead to similar (acceptable) model responses. This observation has significant implications for land‐surface and hydrologic model development and, if not addressed properly, may undermine the credibility of the model in prediction. The framework effectively constrains the model behaviour (by constraining posterior parameter space) and results in more credible representation of hydrology across the watershed.
Treatment With a Soluble Bone Morphogenetic Protein Type 1A Receptor (BMPR1A) Fusion Protein Increases Bone Mass and Bone Formation in Mice Subjected to Hindlimb Unloading
Authors: Ko Frank C. , Van Vliet Miranda , Ellman Rachel , Grasso Daniel , Brooks Daniel J , Spatz Jordan M , Conlon Chrissy , Aguirre J Ignacio , Wronski Thomas J , Bouxsein Mary L
Published: July 2017

Previous work has shown that the soluble murine BMPR1A–fusion protein (mBMPR1A‐mFc) binds to BMP2 and BMP4 with high affinity, preventing downstream signaling. Further, treatment of intact and ovariectomized mice with mBMPR1A‐mFc leads to increased bone mass, and improved bone microarchitecture and strength, via increased bone formation and reduced resorption. In this study, we tested the effects of mBMPR1A‐mFc on disuse‐induced bone loss caused by 21 days of hindlimb unloading (HLU) via tail suspension versus cage controls (CONs). Adult female C57BL/6J mice (12 weeks old) were assigned to one of four groups (n = 10 each): CON‐VEH; CON‐mBMPR1A‐mFc; HLU‐VEH; and HLU‐mBMPR1A‐mFc. Mice were injected subcutaneously with VEH or mBMPR1A‐mFc (4.5 mg/kg, 2×/week). Leg BMD declined in the HLU‐VEH group (–5.3% ± 1.3%), whereas it was unchanged in HLU‐mBMPR1A‐mFc (–0.3% ± 0.9%, p < 0.05 versus HLU‐VEH). Leg BMD increased significantly more in CON‐mBMPR1A‐mFc than CON‐VEH (10.2% ± 0.6% versus 4.4% ± 0.8%). In the femur, trabecular, and cortical bone microarchitecture was worse in the HLU‐VEH compared to CON‐VEH mice, whereas mBMPR1A‐mFc treatment for 3 weeks led to greater Tb.BV/TV, Tb.Th, and midshaft Ct.Th in both the HLU and CON groups compared to comparable VEH‐treated counterparts (p < 0.05). HLU‐mBMPR1A‐mFc mice also had 21% greater failure load (p < 0.05) compared to their VEH‐treated counterparts. Dynamic histomorphometry indicated that treatment with mBMPR1A‐mFc led to significantly greater mineralizing surface and mineral apposition rate, resulting in a 3.5‐fold and fivefold higher bone formation rate in the mBMPR1A‐mFc‐treated CON and HLU animals versus VEH groups, respectively. mBMPR1A‐mFc‐treated mice had a similar osteoblast surface but significantly lower osteoclast surface than VEH‐treated animals in both the CON and HLU groups. Altogether, these findings suggest that treatment with the soluble BMPR1A fusion protein may be useful for maintenance of skeletal integrity in the setting of disuse‐induced bone loss. © 2017 The Authors JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.
Acute painful autoimmune neuropathy: A variant of Guillain‐Barré syndrome
Authors: Yuki Nobuhiro , Chan Amanda C. , Wong Anna Hiu Yi , Inoue Takayuki , Yokai Masafumi , Kurihara Takashi , Devaux JérôMe J. , Wilder‐Smith Einar
Published: July 2017

Introduction

We present a painful small‐fiber neuropathy variant of Guillain‐Barré syndrome characterized by antecedent infectious symptoms, hyporeflexia, and albuminocytologic dissociation.

Methods

Two patients received intravenous immunoglobulin, one corticosteroids.

Results

The patients subsequently improved. Immunoglobulin G (IgG) antibodies in their acute phase sera strongly bound to murine small nerve fibers, and the binding disappeared during the convalescent phase. Serum transfer to a murine nociceptive model induced transient alteration in thermal pain responses.

Discussion

Our case series suggest that an acute transient immune response can be directed against small nerve fibers, and that patients so affected can exhibit features of Guillain‐Barré syndrome. Muscle Nerve 57: 320–324, 2018
The State of the Art of Hybrid RANS/LES Modeling for the Simulation of Turbulent Flows
Authors: Chaouat Bruno
Published: July 2017

This review presents the state of the art of hybrid RANS/LES modeling for the simulation of turbulent flows. After recalling the modeling used in RANS and LES methodologies, we propose in a first step a theoretical formalism developed in the spectral space that allows to unify the RANS and LES methods from a physical standpoint. In a second step, we discuss the principle of the hybrid RANS/LES methods capable of representing a RANS-type behavior in the vicinity of a solid boundary and an LES-type behavior far away from the wall boundary. Then, we analyze the principal hybrid RANS/LES methods usually used to perform numerical simulation of turbulent flows encountered in engineering applications. In particular, we investigate the very large eddy simulation (VLES), the detached eddy simulation (DES), the partially integrated transport modeling (PITM) method, the partially averaged Navier-Stokes (PANS) method, and the scale adaptive simulation (SAS) from a physical point of view. Finally, we establish the connection between these methods and more precisely, the link between PITM and PANS as well as DES and PITM showing that these methods that have been built by different ways, practical or theoretical manners have common points of comparison. It is the opinion of the author to consider that the most appropriate method for a particular application will depend on the expectations of the engineer and the computational resources the user is prepared to expend on the problem.
Performance of [18F]flutemetamol amyloid imaging against the neuritic plaque component of CERAD and the current (2012) NIA‐AA recommendations for the neuropathologic diagnosis of Alzheimer's disease
Authors: Salloway Stephen , Gamez Jose E. , Singh Upinder , Sadowsky Carl H. , Villena Teresa , Sabbagh Marwan N. , Beach Thomas G. , Duara Ranjan , Fleisher Adam S. , Frey Kirk A. , Walker Zuzana , Hunjan Arvinder , Escovar Yavir M. , Agronin Marc E. , Ross Joel , Bozoki Andrea , Akinola Mary , Shi Jiong , Vandenberghe Rik , Ikonomovic Milos D. , Sherwin Paul F. , Farrar Gill , Smith Adrian P.L. , Buckley Christopher J. , Thal Dietmar Rudolf , Zanette Michelle , Curtis Craig
Published: July 2017

Introduction

Performance of the amyloid tracer [18F]flutemetamol was evaluated against three pathology standard of truth (SoT) measures including neuritic plaques (CERAD “original” and “modified” and the amyloid component of the 2012 NIA‐AA guidelines).

Methods

After [18F]flutemetamol imaging, 106 end‐of‐life patients who died underwent postmortem brain examination for amyloid plaque load. Blinded positron emission tomography scan interpretations by five independent electronically trained readers were compared with pathology measures.

Results

By SoT, sensitivity and specificity of majority image interpretations were, respectively, 91.9% and 87.5% with “original CERAD,” 90.8% and 90.0% with “modified CERAD,” and 85.7% and 100% with the 2012 NIA‐AA criteria.

Discussion

The high accuracy of either CERAD criteria suggests that [18F]flutemetamol predominantly reflects neuritic amyloid plaque density. However, the use of CERAD criteria as the SoT can result in some false‐positive results because of the presence of diffuse plaques, which are accounted for when the positron emission tomography read is compared with the 2012 NIA‐AA criteria.
Sigmar1 regulates endoplasmic reticulum stress-induced C/EBP-homologous protein expression in cardiomyocytes
Authors: Alam Shafiul , Abdullah Chowdhury S. , Aishwarya Richa , Orr A. Wayne , Traylor James , Miriyala Sumitra , Panchatcharam Manikandan , Pattillo Christopher B. , Bhuiyan Md. Shenuarin
Published: July 2017

C/EBP-homologous protein (CHOP) is a ubiquitously expressed stress-inducible transcription factor robustly induced by maladaptive endoplasmic reticulum (ER) stresses in a wide variety of cells. Here, we examined a novel function of Sigma 1 receptor (Sigmar1) in regulating CHOP expression under ER stress in cardiomyocytes. We also defined Sigmar1-dependent activation of the adaptive ER-stress pathway in regulating CHOP expression. We used adenovirus-mediated Sigmar1 overexpression as well as Sigmar1 knockdown by siRNA in neonatal rat ventricular cardiomyocytes (NRCs); to induce ER stress, cardiomyocytes were treated with tunicamycin. Sigmar1-siRNA knockdown significantly increased the expression of CHOP and significantly induced cellular toxicity by sustained activation of ER stress in cardiomyocytes. Sigmar1 overexpression decreased the expression of CHOP and significantly decreased cellular toxicity in cells. Using biochemical and immunocytochemical experiments, we also defined the specific ER-stress pathway associated with Sigmar1-dependent regulation of CHOP expression and cellular toxicity. We found that Sigmar1 overexpression significantly increased inositol requiring kinase 1α (IRE1α) phosphorylation and increased spliced X-box-binding proteins (XBP1s) expression as well as nuclear localization. In contrast, Sigmar1 knockdown significantly decreased IRE1α phosphorylation and decreased XBP1s expression as well as nuclear transport. Taken together, these results indicate that Sigmar1-dependent activation of IRE1α-XBP1s ER-stress response pathways are associated with inhibition of CHOP expression and suppression of cellular toxicity. Hence, Sigmar1 is an essential component of the adaptive ER-stress response pathways eliciting cellular protection in cardiomyocytes.
Cleanup of Cold War nuclear waste drags on
Authors: Kramer David
Published: July 2017

Despite billions of dollars spent preparing to treat and stabilize liquid radioactive wastes, cleaning out leaking tanks at the former nuclear production site in Hanford, Washington, will take decades more.
As student labor movements grow, scientists turn activist
Authors: Smart Ashley G.
Published: July 2017

A 2016 federal ruling gave graduate assistants the right to unionize. Now students on both sides of the issue are mobilizing.
Clippers, yachts, and the false promise of the wave line
Authors: Ferreiro Larrie D. , Pollara Alexander
Published: July 2017

John Scott Russell’s 19th-century theory of ship design promised speed and delivered elegance. But, ultimately, it didn’t hold water.
Infants note the notes
Authors: Lau Bonnie K. , Ng Manson
Published: July 2017

Perceiving pitch differences requires the brain to process complex sounds. Remarkably, three-month-old infants with immature brains can hear a wrong note in the children’s song “Twinkle, Twinkle, Little Star.”
Mutant p53 potentiates the oncogenic effects of insulin by inhibiting the tumor suppressor DAB2IP
Authors: Valentino Elena , Bellazzo Arianna , Di Minin Giulio , Sicari Daria , Apollonio Mattia , Scognamiglio Giosuè , Di Bonito Maurizio , Botti Gerardo , Del Sal Giannino , Collavin Licio
Published: July 2017

Significance

Understanding the molecular factors that shape the impact of hyperinsulinemia on cancer progression would improve treatment of obese and diabetic patients. This work contributes to such understanding by showing that gain-of-function p53 mutations can modify the response of cancer cells to insulin, increasing proliferation and motility through enhanced activation of AKT.
Relevance of Kinesiophobia in Relation to Changes Over Time Among Patients After an Acute Coronary Artery Disease Event
Authors: Bäck Maria , Lundberg Mari , Cider Åsa , Herlitz Johan , Jansson Bengt
Published: July 2017

Purpose:

To identify levels of kinesiophobia during the first 4 months after an acute episode of coronary artery disease (CAD), while controlling for gender, anxiety, depression, and personality traits.

Methods:

In all, 106 patients with CAD (25 women), mean age 63.1 ± 11.5 years, were included in the study at the cardiac intensive care unit, Sahlgrenska University Hospital, Sweden. The patients completed questionnaires at 3 time points: in the cardiac intensive care unit (baseline), 2 weeks, and 4 months after baseline. The primary outcome measure was kinesiophobia. Secondary outcome measures were gender, anxiety, depression, harm avoidance, and positive and negative affect. A linear mixed model procedure was used to compare kinesiophobia across time points and gender. Secondary outcome measures were used as covariates.

Results:

Kinesiophobia decreased over time (P = .005) and there was a significant effect of gender (P = .045; higher values for women). The presence of a high level of kinesiophobia was 25.4% at baseline, 19% after 2 weeks, and 21.1% after 4 months. Inclusion of the covariates showed that positive and negative affect and harm avoidance increased model fit. The effects of time and gender remained significant.

Conclusions:

This study highlights that kinesiophobia decreased over time after an acute CAD episode. Nonetheless, a substantial part of the patients were identified with a high level of kinesiophobia across time, which emphasizes the need for screening and the design of a treatment intervention.
Widespread pleiotropy confounds causal relationships between complex traits and diseases inferred from Mendelian randomization
Authors: Verbanck Marie , Chen Chia-Yen , Neale Benjamin , Do Ron
Published: July 2017

A fundamental assumption in inferring causality of an exposure on complex disease using Mendelian randomization (MR) is that the genetic variant used as the instrumental variable cannot have pleiotropic effects. Violation of this ‘no pleiotropy’ assumption can cause severe bias. Emerging evidence have supported a role for pleiotropy amongst disease-associated loci identified from GWA studies. However, the impact and extent of pleiotropy on MR is poorly understood. Here, we introduce a method called the Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO) test to detect and correct for pleiotropy in multi-instrument summary-level MR testing. We show using simulations that existing approaches are less sensitive to the detection of pleiotropy when it occurs in a subset of instrumental variables, as compared to MR-PRESSO. Next, we show that pleiotropy is widespread in MR, occurring in 41% amongst significant causal relationships (out of 4,250 MR tests total) from pairwise comparisons of 82 complex traits and diseases from summary level genome-wide association data. We demonstrate that pleiotropy causes distortion between-168% and 189% of the causal estimate in MR. Furthermore, pleiotropy induces false positive causal relationships-defined as those causal estimates that were no longer statistically significant in the pleiotropy corrected MR test but were previously significant in the naive MR test-in up to 10% of the MR tests using a P < 0.05 cutoff that is commonly used in MR studies. Finally, we show that MR-PRESSO can correct for distortion in the causal estimate in most cases. Our results demonstrate that pleiotropy is widespread and pervasive, and must be properly corrected for in order to maintain the validity of MR.
Semantically Defined Subdomains of Functional Neuroimaging Literature and their Corresponding Brain Regions
Authors: Alhazmi Fahd H , Beaton Derek , Abdi Hervé
Published: July 2017

The functional neuroimaging literature has become increasingly complex and thus difficult to navigate. This complexity arises from the rate at which new studies are published and from the terminology that varies widely from study-to-study and even more so from discipline-to-discipline. One way to investigate and manage this problem is to build a “semantic space” that maps the different vocabulary used in functional neuroimaging literature. Such a semantic space will also help identify the primary research domains of neuroimaging and their most commonly reported brain regions. In this work, we analyzed the multivariate semantic structure of abstracts inNeurosynthand found that there are six primary domains of the functional neuroimaging literature each with their own preferred reported brain regions. Our analyses also highlight possible semantic sources of reported brain regions within and across domains because some research topics (e.g., memory disorders, substance use disorder) use heterogeneous terminology. Furthermore, we highlight the growth and decline of the primary domains over time. Finally, we note that our techniques and results form the basis of a “recommendation engine” that could help readers better navigate the neuroimaging literature.
Highly efficient site-specific mutagenesis in Malaria mosquitoes using CRISPR
Authors: Li Ming , Akbari Omar S. , White Bradley J.
Published: July 2017

Anophelesmosquitoes transmit at least 200 million annual malaria infections worldwide. Despite considerable genomic resources, mechanistic understanding of biological processes inAnopheleshas been hampered by a lack of tools for reverse genetics. Here, we report successful application of the CRISPR/Cas9 system for highly efficient, site-specific mutagenesis in the diverse malaria vectorsAnopheles albimanus,Anopheles coluzzii, andAnopheles funestus. When guide RNAs and Cas9 are injected at high concentration, germline mutations are common and usually bi-allelic allowing for the rapid creation of stable, mutant lines for reverse genetic analysis. Our protocol should enable researchers to dissect the molecular and cellular basis of anopheline traits critical to successful disease transmission, potentially exposing new targets for malaria control.
Cell type-specific expression profiling sheds light on the development of a peculiar neuron, housing a complex organelle
Authors: Sunagar Kartik , Columbus-Shenkar Yaara , Fridrich Arie , Gutkovich Nadya , Aharoni Reuven , Moran Yehu
Published: July 2017

Specialized neurons called cnidocytes define the phylum Cnidaria. They possess an ‘explosive’ organelle called cnidocyst that is important for prey capture and antipredator defense. An extraordinary morphological and functional complexity of the cnidocysts has inspired numerous studies to investigate their structure and development. However, the transcriptomes of the cells bearing these unique organelles are yet to be characterized, impeding our understanding of the genetic basis of their biogenesis. By generating transgenic lines of the sea anemoneNematostella vectensisusing the CRISPR/Cas9 system, we have characterized cell-type specific transcriptomic profiles of various stages of cnidocyte maturation and show that nematogenesis (the formation of functional cnidocysts) is underpinned by dramatic shifts in the spatiotemporal gene expression. We also highlight the stark fall in transcriptional-levels of toxin and structural protein coding genes within cnidocytes with the maturation of capsule. We further reveal that the majority of upregulated genes and enriched biochemical pathways specific to cnidocytes are yet to be characterized. Finally, we unravel the recruitment of a metazoan stress-related transcription factor complex into nematogenesis and highlight its role in the formation of a structural protein of the cnidocyst wall. Thus, we provide novel insights into the biology, development, and evolution of cnidocytes.
Sleep deprivation negatively impacts reproductive output inDrosophila melanogaster
Authors: Potdar Sheetal , Daniel Danita K. , Thomas Femi A. , Lall Shraddha , Sheeba Vasu
Published: July 2017

Most animals sleep or exhibit a sleep-like state, yet the adaptive significance of this phenomenon remains unclear. Although reproductive deficits are associated with lifestyle induced sleep deficiencies, how sleep loss affects reproductive physiology is poorly understood, even in model organisms. We aimed to bridge this mechanistic gap by impairing sleep in female fruit flies and testing its effect on egg output. We find that sleep deprivation by feeding caffeine or by mechanical perturbation results in decreased egg output. Transient activation of wake-promoting dopaminergic neurons decreases egg output in addition to sleep levels, thus demonstrating a direct negative impact of sleep deficit on reproductive output. Similarly, loss-of-function mutation in dopamine transporterfumin(fmn)leads to both significant sleep loss and lowered fecundity. This demonstration of a direct relationship between sleep and reproductive fitness indicates a strong driving force for the evolution of sleep.
Decreased intra-lymphocyte cytokines measurement in septic shock patients: a whole blood proof of concept study
Authors: Letessier Wilfried , Demaret Julie , Gossez Morgane , Allam Camille , Venet Fabienne , Rimmelé Thomas , Monneret Guillaume
Published: July 2017

Functional testing protocols are thought to be the gold standard for the exploration of the immune system. However, in terms of routine analysis, they present numerous drawbacks and consequently their use is mainly limited to research applications. In the clinical context of septic shock, characterized by marked lymphocyte alterations, a new approach for lymphocyte intracellular cytokine measurement in whole blood upon was evaluated in a proof-of-concept study. Following lymphocyte activation, simultaneous intracellular labeling of Interferon-γ (IFN-γ), Tumor Necrosis Factor-α (TNF-α), and Interleukin-2 (IL-2) was performed in CD4+and CD8+T cells (identified by surface marking). The analysis was carried out by flow cytometry (6 colors). Results obtained in septic patients (n = 22) were compared to those of healthy volunteers (n = 8). Independently of lymphopenia, there were significant differences between groups. In particular there was significant decrease in the production of IL-2 and TNF-α in septic patients, while the production of IFN-γ was not significantly altered. Polyfunctional results showed that patients presented with increased percentages of triple negative lymphocytes. In contrast, volunteers had higher proportions of triple positive cells. The approach could be performed in a robust and consistent way, taking 4.5 hours to complete. Moreover, clear differences could be observed between clinical groups with this modified method. These characteristics illustrate the potential of this novel whole blood protocol for clinical applications. However, further research is required to determine the applicability compared to alternative test and to evaluate clinical performances in larger cohorts of patients.
Engineering post-translational proofreading to discriminate non-standard amino acids
Authors: Kunjapur Aditya M. , Stork Devon A. , Kuru Erkin , Vargas-Rodriguez Oscar , Landon Matthieu , Söll Dieter , Church George M.
Published: July 2017

Progress in genetic code expansion requires accurate, selective, and high-throughput detection of non-standard amino acid (NSAA) incorporation into proteins. Here, we discover how the N-end rule pathway of protein degradation applies to commonly used NSAAs. We show that several NSAAs are N-end stabilizing and demonstrate that other NSAAs can be made stabilizing by rationally engineering the N-end rule adaptor protein ClpS. We use these insights to engineer a synthetic quality control method, termed “Post-Translational Proofreading” (PTP). By implementing PTP, false positive proteins resulting from misincorporation of structurally similar standard amino acids or undesired NSAAs rapidly degrade, enabling high-accuracy discrimination of desired NSAA incorporation. We illustrate the utility of PTP during evolution of the biphenylalanine orthogonal translation system used for synthetic biocontainment. Our new OTS is more selective and confers lower escape frequencies and greater fitness in all tested biocontained strains. Our approach presents a new paradigm for molecular recognition of amino acids in target proteins.
Plant‐ants use resistance‐related plant odours to assess host quality before colony founding
Authors: Razo‐Belman Rosario , Molina‐Torres Jorge , Martínez Octavio , Heil Martin
Published: July 2017

Establishing a horizontally transmitted mutualism is a critical step for many organisms, particularly when an individual can engage with only one partner over its lifetime. Ant foundresses shed their wings before they start to lay eggs, which makes host choice particularly critical for plant‐ants that exclusively colonize myrmecophytes.

Volatile organic compounds (VOCs) can indicate the identity and physiological condition of an individual and frequently serve as signals or cues that facilitate partner choice. Thus, we hypothesized that obligate plant‐ants use VOCs to determine the quality of potential host plants.

Indeed, winged females of the plant‐ant, Pseudomyrmex ferrugineus, used plant odours to identify high‐quality acacia hosts among different species and among individuals of the same species. The VOC blend of a branch was related to reward production and, interestingly, the least attractive blend contained the highest number of compounds.

Although only seven different VOCs could be detected in the blend of the high‐reward host species, the low‐reward host emitted 13 different compounds, among which (S)‐(‐)‐limonene and β‐linalool were the dominant ones. Complementing the odour of the high‐reward host with (S)‐(‐)‐limonene, β‐linalool or α‐terpinene reduced its attractiveness. Strikingly, these compounds inhibited bacterial pathogens of the host plant.

Synthesis. Plant‐ants can use host plant odours that contain resistance‐related VOCs to judge on host quality, likely because of negative crosstalk between direct resistance to disease and investment in ant‐mediated defence. VOCs can serve as cues that provide reliable information for partner choice, particularly when their emission results from a physiological process that causally relates to the quality of an individual as a mutualist.
Plant–soil feedbacks mediate shrub expansion in declining forests, but only in the right light
Authors: Pfennigwerth Alix A. , Van Nuland Michael E. , Bailey Joseph K. , Schweitzer Jennifer A.
Published: July 2017

Contemporary global change, including the widespread mortality of foundation tree species, is altering ecosystems and plant communities at unprecedented rates. Plant–soil interactions drive myriad community dynamics, and we hypothesized that such interactions may be an important driver of succession following the loss of foundation tree species.

We examined whether plant–soil biota interactions, in the context of a putatively important light gradient associated with foundation tree decline, mediate the expansion ofRhododendron maximumin southeasternUSforests whereTsuga canadensis(eastern hemlock), a dominant foundation tree species, is in decline. Using an 11‐month, controlled inoculation experiment paired with Illumina sequencing, we tested the following hypotheses: (1) Relative to conspecific (R. maximum‐conditioned) soils,R. maximumseedlings have higher performance in soils conditioned byT. canadensisand lower performance in interspace soils (conditioned by neitherT. canadensisnorR. maximum) due to variation in soil fungal biota, and (2) seedling performance is greater in high‐light vs. low‐light environments (matching environments under infested vs. uninfestedT. canadensiscrowns, respectively).

In partial support of the first hypothesis, we found thatR. maximumseedling performance was highest inT. canadensis‐conditioned andR. maximum‐conditioned soils and lowest in interspace soils. Mechanistically, soils conditioned byT. canadensisandR. maximumhad more ericoid and ectomycorrhizal fungi, less saprotrophic fungi, and were less species‐rich than interspace soils, and variation in these community traits predicted substantial variation inR. maximumseedling biomass. However, in support of our second hypothesis, soil effects on plant performance were evident in high light only; in low light, soil inoculation did not affect plant performance and plants performed worse on average.

Synthesis. Our findings suggest that interactions with soil biota act synergistically with altered abiotic environments to mediate species responses to widespread foundation tree mortality, providing evidence for a novel mechanism of plant response to large‐scale disturbance. Examining plant–soil interactions in the context of relevant abiotic gradients can, therefore, enhance our understanding, predictions and management of community development processes following forest disturbance.
Effectiveness of intensive practice nurse counselling versus brief general practitioner advice, both combined with varenicline, for smoking cessation: a randomized pragmatic trial in primary care
Authors: van Rossem Carolien , Spigt Mark , Viechtbauer Wolfgang , Lucas Annelies E. M. , van Schayck Onno C. P. , Kotz Daniel
Published: July 2017

Aims

To study the effectiveness of intensive counselling by a practice nurse (PN) versus brief advice by a general practitioner (GP), each combined with pharmacotherapy, for 6 months’ tobacco abstinence (primary outcome). Secondary outcomes included 12‐month abstinence, medication adherence and incremental costs per life‐year gained.

Design

A multi‐site (n = 10), two‐group, parallel, pragmatic randomized controlled trial.

Setting

A network of primary health‐care centres in the Netherlands.

Participants

A total of 295 adult daily smokers (mean age = 48 years; mean cigarettes/day = 19).

Intervention and comparator

Patients were randomized to receive individual counselling by a practice nurse (PN) (n = 149) or brief advice by a general practitioner (GP) (146). All patients received 12 weeks of open‐label varenicline.

Measurements

The primary outcome was prolonged biochemically validated abstinence from weeks 9 to 26 after treatment initiation. Secondary outcomes included abstinence from weeks 9 to 52, good dosing adherence (> 80% days taken) and incremental costs per life‐year gained.

Findings

Abstinence rates in the PN versus GP groups were 32.2% (n = 48) versus 39.0% [n = 57; odds ratio (OR) = 0.71; 95% confidence interval (CI) = 0.44–1.16] from weeks 9 to 26 and 25.5% (n = 38) versus 28.8% (n = 42; OR = 0.84, 95% CI = 0.50–1.43) from weeks 9 to 52, respectively. Values of the Bayes factor indicated that the PN and GP were equally effective. Good dosing adherence was significantly lower in the PN (45.5%, n = 56/123) than in the GP group (62.0%, n = 75/121; OR = 0.45, 95% CI = 0.26–0.77), and the incremental costs per life‐year gained were –€416.10.

Conclusions

Among people seeking help to stop smoking from their general practice, one‐off brief advice from a general practitioner appears to be as effective as several sessions of behavioural support from a practice nurse when smoking cessation medication is provided.
Is cystic artery lymph node excision during laparoscopic cholecystectomy a marker of technique?
Authors: Wysocki Arkadiusz P. , Murphy Skyle , Ware Robert S.
Published: July 2017

Background

In order to minimize bile duct injury, experts suggest that dissection during laparoscopic cholecystectomy (LC) should be performed lateral to the lymph node (LN). This study aims to determine whether the frequency of excision of the LN is related to patient factors, disease severity or surgical difficulty.

Methods

All LCs performed or supervised by one surgeon were identified from a prospective database. The presence of LN was retrospectively determined by reviewing the gallbladder histology report.

Results

The LN was identified in 10.4% of 1332 cholecystectomies. The American Society of Anesthesiologists class 3 was associated with a lower rate of LN excision compared with class 1 (odds ratio: 0.36; P = 0.049) as was the presence of a senior surgical trainee (odds ratio: 0.18; P < 0.001). Rate of LN excision was independent of patient demographic and clinical characteristics, including indication for cholecystectomy, conversion to open, gallbladder perforation, cholangiography, bile duct exploration and overall surgical difficulty.

Conclusions

The frequency with which the LN is excised during LC by the one surgeon is independent of the majority of clinical and surgical factors and may represent a surrogate marker of surgical technique. Whether this is related to the rate of bile duct injury remains to be determined.
A one‐step immune‐chromatographic Helicobacter pylori stool antigen test for children was quick, consistent, reliable and specific
Authors: Kalach Nicolas , Gosset Pierre , Dehecq Eric , Decoster Anne , Georgel Anne‐France , Spyckerelle Claire , Papadopoulos Stephanos , Dupont Christophe , Raymond Josette
Published: July 2017

Aim

This French study assessed a quick, noninvasive, immuno‐chromatographic, Helicobacter pylori (H. pylori) stool antigen test for detecting infections in children.

Methods

We enrolled 158 children, with a median age of 8.5 years (range eight months to 17 years), with digestive symptoms suggesting upper gastrointestinal tract disease. Upper digestive endoscopy was performed with gastric biopsy specimens for histology, a rapid urease test, culture test and quantitative real‐time polymerase chain reaction. The H. pylori stool antigen test was performed twice for each child and the results were compared to the reference method.

Results

The reference methods showed that 23 (14.6%) of the 158 children tested were H. pylori positive. The H. pylori stool antigen test showed 91.3% sensitivity, with a 95% confidence interval (95% CI) of 86.9–95.6 and 97% specificity (95% CI 94.3–99.6), 30.84 positive likelihood ratio and 0.09 negative likelihood ratio. The test accuracy was 96.2% (95% CI 93.2–99.1). The two blinded independent observers produced identical H. pylori stool antigen test results and the Kappa coefficient for the H. pylori stool antigen test was one.

Conclusion

The H. pylori stool antigen test was found to be a consistent, reliable, quick and specific test for detecting the H. pylori infection in children.
Informal sector taxes and equity: Evidence from presumptive taxation in Zimbabwe
Authors: Dube Godwin , Casale Daniela
Published: July 2017

Using a mixed‐methods approach, this article evaluates the equity implications of Zimbabwe's presumptive tax system, introduced in 2005 to raise revenue from the country's growing informal sector. The representative taxpayer method, which compares the hypothetical tax burdens of formal and informal sector taxpayers at varying income levels, shows that the presumptive tax regime undermines both vertical and horizontal equity. In addition, interviews with key informants from the tax authorities, other relevant organizations and informal sector operators were conducted to probe issues around collection, compliance and perceptions of fairness. The qualitative data suggest that weak enforcement, with more visible informal activities bearing the brunt of the tax burden, and selective (and sometimes politically motivated) application of the legislation, compromise equity further.
Coronal advanced flap in combination with a connective tissue graft. Is the thickness of the flap a predictor for root coverage? A prospective clinical study
Authors: Garces‐McIntyre Teresa , Carbonell Josep Maria , Vallcorba Lluís , Santos Antonio , Valles Cristina , Nart José
Published: July 2017

Aim

Evaluate if there is any relationship between the flap thickness (FT) and the presence of complete root coverage (CRC) when performing coronally advanced flaps in combination with a connective tissue graft (CTG).

Materials and methods

Prospective clinical study, in which multiple Miller class I and II recessions were treated with a coronally advanced flap and a CTG standardized at 1 mm of thickness. Individual stents permitted repeated measurements of conventional periodontal parameters at the same point. The primary outcome variable was CRC. Secondary outcomes were recession reduction, gingival thickness and width of keratinized tissue (KT) achieved at 6 months post‐surgery.

Results

Forty‐five recessions (2.4 ± 0.75 mm) were treated in 20 patients. Mean root coverage was 93.4 ± 10.98%; 65% achieved CRC. The mean FT was 1.01 mm ± 0.64 mm and 1.01 ± 0.61 mm at 2 and 5 mm from the gingival margin, respectively. No relationship could be found between FT and CRC (p > .05). Statistical significant changes (p < .05) were observed for recession depth, clinical attachment level, KT and soft tissue thickness at the end of the study.

Conclusions

Flap thickness seems not to be a predictor for CRC when performing a coronally advanced flap plus a CTG. This technique may be of choice when treating thin biotypes.
Linking Data‐Rich Environments with Service Innovation in Incumbent Firms: A Conceptual Framework and Research Propositions
Authors: Troilo Gabriele , De Luca Luigi M. , Guenzi Paolo
Published: July 2017

The impact of big data on innovation is not only driven by technology and analytics. It involves a transformation of the organizational culture, structures, processes, roles, and capabilities that underpin the innovation process. Understanding these factors is particularly important for service innovators, given the strong interdependence between the organizational context and technology in service companies. Moreover, in many of these organizations, the innovation process is still deeply rooted in a non‐digital past. This study answers the call to understand what are the key characteristics of a systematic process for service innovation in data‐rich environments. In particular, the authors investigate the primary factors that enable existing service organizations to capture the innovation potential inherent in data‐rich environments. To this aim, the authors implemented a two‐step research design. First, they integrated the service innovation and information systems literatures in a unified conceptual framework that articulates the relationship between data‐rich environments and service innovation from an organizational perspective. Second, they carried out 40 semi‐structured interviews in seven large service firms, which allowed them to refine and populate the initial framework with typologies, concepts, and examples from the field. A major contribution of this study is to articulate the concept of data density, as three distinct processes (pattern spotting, real‐time decisioning, and synergistic exploration) connecting data‐rich environments with service innovation opportunities. Finally, the authors identified a set of organizational enablers that facilitate the links among technology, data density processes, and service innovation. The findings of this study offer a roadmap for service managers who need to align the service innovation process of their organizations with the opportunities offered by data‐rich environments.
Differential growth costs and nitrogen fixation in Cytisus multiflorus (L′Hér.) Sweet and Cytisus scoparius (L.) Link are mediated by sources of inorganic N
Authors: Pérez‐Fernández M. A. , Calvo‐Magro E. , Rodríguez‐Sánchez J. , Valentine A.
Published: July 2017

Shrubby legumes in Mediterranean‐type ecosystems face strong nutrient limitations that worsen in summer, when water is absent. Nitrogen‐fixing legumes are likely to be able to switch between soil N and atmospheric N (N2) sources to adjust the C costs of N acquisition in different seasons.

We investigated the utilisation of different inorganic N sources by two indigenous shrubby legumes (Cytisus multiflorus and Cytisus scoparius). Plant performance in terms of photosynthesis and biomass production was also analysed. Plants were cultivated in sterile river sand supplied with Hoagland nutrient solution, grown in N‐free nutrient solution and inoculated with effective rhizobial strains from nodules of adult plants of the same species. A second treatment consisted of plants given 500 μm NH4NO3 added into the nutrient solution. In a third treatment, plants were watered with another source of N (500 μm NH4NO3) as well as being inoculated with effective rhizobial strains.

The application of NH4NO3 to the legumes resulted in a larger increase in plant dry matter. Carbon construction costs were higher in plants supplied with mineral and symbiotic N sources and always higher in the endemic C. multiflorus. Differences in photosynthesis rates were only observed between species, regardless of the N source. Non‐fertilised inoculated plants had more effective root nodules and a clear dependence on N2 fixation.

We propose that the ability of C. scoparius to change N source makes it a plastic species, which would account for its broader distribution in nature.
Handling Delays in Yaw Rate Control of Electric Vehicles Using Model Predictive Control With Experimental Verification
Authors: Jalali Milad , Khajepour Amir , Chen Shih-ken , Litkouhi Bakhtiar
Published: July 2017

In this paper, a new approach is proposed to deal with the delay in vehicle stability control using model predictive control (MPC). The vehicle considered here is a rear-wheel drive electric (RWD) vehicle. The yaw rate response of the vehicle is modified by means of torque vectoring so that it tracks the desired yaw rate. Presence of delays in a control loop can severely degrade controller performance and even cause instability. The common approaches for handling delays are often complex in design and tuning or require an increase in the dimensions of the controller. The proposed method is easy to implement and does not entail complex design or tuning process. Moreover, it does not increase the complexity of the controller; therefore, the amount of online computation is not appreciably affected. The effectiveness of the proposed method is verified by means of carsim/simulink simulations as well as experiments with a rear-wheel drive electric sport utility vehicle (SUV). The simulation results indicate that the proposed method can significantly reduce the adverse effect of the delays in the control loop. Experimental tests with the same vehicle also point to the effectiveness of this technique. Although this method is applied to a vehicle stability control, it is not specific to a certain class of problems and can be easily applied to a wide range of model predictive control problems with known delays.
Implementation and Deployment of an Intelligent Industrial Wireless System for Induction Motor Monitoring
Authors: Adissi Marcéu O. , Lima Filho Abel C. , Gomes Ruan D. , Silva Diógenes M. G. B. , Belo Francisco A.
Published: July 2017

Three-phase induction motors (TIMs) are present in most industrial processes, accounting for more than 60% of the energy consumption in industry. Despite their importance in the productive sector, few motors are properly monitored, mainly due to the high cost of the monitoring equipment and the invasiveness in their installation. This paper presents the implementation and deployment of an industrial wireless sensor network (WSN) to monitor three-phase induction motors. Embedded systems were developed to acquire signals of current and voltage from sensors installed in the motors' terminals, perform local processing to estimate torque and efficiency, and transmit the information through the WSN. The method used to estimate the variables is based on the air-gap torque method. Before the deployment in the industry, experiments were performed to validate the system in laboratory. Finally, the system was employed in a real industrial environment, where different analyses and diagnosis of three motors running were performed. Using the proposed system, the efficiency versus load curves of the motors could be obtained continuously, and an energy loss analysis due to the oversizing of the motors was performed.
Utilizing the Ensemble Kalman Filter and Ensemble Kalman Smoother for Combined State and Parameter Estimation of a Three-Dimensional Towed Underwater Cable Model
Authors: Vidar Grindheim Jan , Revhaug Inge , Pedersen Egil
Published: July 2017

A finite difference method (FDM) solving the coupled partial differential equations governing three-dimensional (3D) motions of a towed underwater cable has been implemented in a combined ensemble Kalman filter (EnKF) and ensemble Kalman smoother (EnKS), as a new approach to combined state and parameter estimation for towed underwater cables. A simulation study of the method applied to a seismic streamer has been performed. Cable state variables as well as model parameters are estimated. Parameters estimated are crossline ocean current varying with time as well as cable tangential drag coefficient. The presented results indicate that the method is able to estimate state as well as parameters for seismic streamers.