bluuebunny/crossref_metadata_2025 huggingface dataset:
Exchange protein directly activated by cAMP (EPAC) promotes transcriptional activation of the decidual prolactin gene via CCAAT/enhancer-binding protein in human endometrial stromal cells
Authors: Kusama Kazuya , Tamura Kazuhiro , Bai Hanako , Sakurai Toshihiro , Nishi Hirotaka , Isaka Keiichi , Imakawa Kazuhiko , Yoshie Mikihiro
Published: May 2018

Protein kinase A (PKA) signalling accompanies elevated intracellular cAMP levels during endometrial stromal cell (ESC) decidualisation. Exchange protein directly activated by cAMP (EPAC), an alternate mediator of cAMP signalling, promotes PKA analogue-induced decidualisation; however, the precise mechanism by which EPAC and PKA co-operatively stimulate decidualisation has not been characterised. To examine the role of CCAAT/enhancer-binding protein (C/EBP) in EPAC- and PKA-mediated decidualisation of primary human ESCs, a reporter plasmid containing the 332 bp region upstream from the transcription initiation site of the decidual prolactin (dPRL) gene was generated and the promoter activity was evaluated using a luciferase assay. The dPRL promoter activity was increased by treatment of transfected ESCs with the PKA-selective cAMP analogue N6-phenyl-cAMP (Phe) and enhanced further by co-treatment with the EPAC-selective cAMP analogue 8-(4-chlorophenyltio)-2′-O-methyl cAMP (CPT). Treatment with forskolin, an adenylyl cyclase activator, had a similar effect on reporter activity. Site-directed mutagenesis of the C/EBPβ- and/or C/EBPδ-binding site in the dPRL promoter abolished Phe/CPT-mediated elevation of the reporter activity. EPAC2 knockdown markedly reduced Phe-stimulated C/EBPβ and C/EBPδ mRNA levels, as well as forkhead box O1 (FOXO1) protein levels. These results suggest that EPAC signalling enhances PKA-mediated dPRL expression in ESCs by acting on C/EBP response elements in the promoter region of the gene.
A comparison of charcoal reflectance between crown and surface fire contexts in dry south-west USA forests
Authors: Roos Christopher I. , Scott Andrew C.
Published: May 2018

The historical and modern importance of crown fires in ponderosa pine and dry mixed-conifer forests of the south-west USA has been much debated. The microscopic reflectance of charcoal in polished blocks under oil shows promise as a semiquantitative proxy for fire severity using charcoal from post-fire landscapes. We measured the reflectance of 33 modern charcoal samples to evaluate (1) whether charcoal reflectance can distinguish between crown fires and surface fires in these forests; and (2) whether surface fires with masticated fuels burn with severities similar to surface fires in grass, litter and duff fuels. The charcoal analysed was primarily collected after wildland fires under two different conditions: (l) wildfires with moderate to high severity and crown fire behaviour (n = 17), and (2) prescribed fires with low to moderate severity but no crown fire behaviour (n = 16). Statistical analysis indicates that charcoal reflectance produced in crown fires significantly differs from surface fire charcoal, particularly surface fire charcoal formed in grass, duff and litter fuels. However, charcoal produced from surface fires in masticated fuels is indistinguishable from crown fire charcoal, suggesting that fires in areas that have experienced in situ mastication may have soil impacts similar to crown fires.
Caffeine ingestion changes time‐motion and technical‐tactical aspects in simulated boxing matches: A randomized double‐blind PLA‐controlled crossover study
Authors: Coswig Victor Silveira , Gentil Paulo , Irigon Francine , Del Vecchio Fabrício Boscolo
Published: May 2018

The number of offensive actions and glycolytic energy in combat sports both increase with caffeine (CAF) ingestion. In addition, the effects of CAF on technical‐tactical and time‐motion analysis and physiological parameters in boxing are unknown. This study aimed to investigate the effects of CAF ingestion on physiological parameters and the notational analysis of boxing matches. Ten male boxers were recruited; the participants ingested 6 mg kg−1 BM of CAF or placebo (PLA) 30 min prior to the match in a crossover design. Heart rate (HR) and rate of perceived exertion (RPE) were collected before and after each of three 2 min rounds, interspersed by 1‐min recovery; the matches were recorded for notational analysis. A two‐way ANOVA for repeated measures was used for the physiological variables, and a three‐way ANOVA with repeated measures was used for technical‐tactical and time‐motion variables. Statistical differences were found for HR and RPE between rounds (F(6, 54) = 131.3, p = .001; = 0.93 and F(2, 18) = 40.6, p = .001; = 0.81, respectively) but not between conditions (F(1, 9) = 0.46; p = .51; = 0.05 and F(1, 9) = 0.02, p = .89; = 0.002, respectively). The CAF condition induced a greater duration of interaction blocks (CAF = 6.5 ± 1.8 s; PLA = 4.4 ± 0.9 s; p = .01). Effort:pause ratio was 4.4 s:8.7 s (approx. 1:2) for PLA and 6.5 s:9.4 s (1:1.44) for CAF, which were significantly different (p < .05). In conclusion, 6 mg kg−1 BM of CAF prior to simulated boxing matches induces a greater duration of high‐intensity actions, with no effects on internal load markers.
Futsal task constraints promote transfer of passing skill to soccer task constraints
Authors: Oppici Luca , Panchuk Derek , Serpiello Fabio Rubens , Farrow Damian
Published: May 2018

This study investigated how learning a passing skill with futsal or soccer task constraints influenced transfer to a new task. Futsal (n = 24, 13.6 ± 1.2 years old, 7.0 ± 1.6 years of experience) and soccer (n = 24, 13.6 ± 1.2 years old, 6.8 ± 1.2 years of experience) players performed two 5v5 + goalkeeper modified games – a futsal‐like task (small playing area with the futsal ball) and soccer‐like task (large playing area with the soccer ball). Participants’ passing accuracy and their orientation of attention were assessed during the two tasks. The futsal group improved their passing accuracy (ES = 0.75 ± 0.61) from the futsal‐like to the soccer‐like task, and they were more accurate than soccer players (ES = 2.98 ± 2.96). Conversely, the soccer group's passing accuracy remained stable across the two tasks (ES = 0.10 ± 0.52) and it was similar to the futsal group in the futsal‐like task (ES = 0.58 ± 1.93). This indicates a higher magnitude of transfer (and adaptability) from performing passes in a small playing area with short time to act – futsal task constraints – to a larger playing area with longer time – soccer task constraints – than vice‐versa. Furthermore, the futsal group showed a higher adaptation of attention orientation to the affordances that emerged with the soccer task constraints, which is suggested to be one of the main mechanisms promoting skill transfer. These results encourage soccer practitioners to introduce futsal task constraints to fast‐track players’ ability to functionally adapt perception–action coupling.
The athletes’ visuomotor system – Cortical processes contributing to faster visuomotor reactions
Authors: Hülsdünker Thorben , Strüder Heiko K. , Mierau Andreas
Published: May 2018

Many sports require athletes to rapidly transform visual information into a targeted motor response, a process referred to as visuomotor reaction. On the behavioural level, athletes have long been established to achieve faster simple visuomotor reaction times when compared to non‐athletes. However, although the superior performance in athletes has been attributed to the central nervous system, the underlying neural mechanisms remained poorly studied. More recently, a growing number of neurophysiological and neuroimaging studies systematically addressed the functional and structural modulations in the athletes’ visual and motor systems as well as their contribution to visuomotor performance. This article reviews current research on structural and functional characteristics of the athletes’ cortical visuomotor system associated with simple visuomotor reactions, sports‐specific visuomotor performance and visuomotor training. The primary objective is to shed light on the neural mechanisms potentially contributing to superior visuomotor reaction performance in athletes participating in visuomotor demanding disciplines. A more comprehensive understanding of performance‐determining neural functions could provide great potential for diagnostics and training to improve athletic performance.
Greater fatigability in knee‐flexors vs. knee‐extensors after a standardized fatiguing protocol
Authors: Coratella Giuseppe , Grosprêtre Sidney , Gimenez Philippe , Mourot Laurent
Published: May 2018

The present study aimed to investigate the effects of a standardized fatiguing protocol on central and peripheral fatigue in knee‐flexors and knee‐extensors. Thirteen healthy men (age: 23 ± 3 years; height: 1.78 ± 0.09 m; body‐mass: 73.6 ± 9.2 kg) volunteered for the present study. Maximal voluntary contraction (MVC), Electromyography (EMG) activity, voluntary activation level (VAL) as an index of central fatigue and twitch potentiation as an index of peripheral fatigue were measured before and after the fatiguing protocol. The fatiguing protocol consisted of a 0.6 duty‐cycle to exhaustion (6 s isometric contraction, 4 s recovery) at 70% MVC. After the fatiguing protocol, MVC decreased in both (Effect‐size (ES) = 1.14) and knee‐extensors (ES = 1.14), and EMG activity increased in both knee‐flexors (ES = 2.33) and knee‐extensors (ES = 1.54). Decreases in VAL occurred in knee‐flexors (ES = 0.92) but not in knee‐extensors (ES = 0.04). Decreases in potentiation occurred in both knee‐flexors (ES = 0.84) and knee‐extensors (ES = 0.58). The greater central occurrence of fatigue in knee‐flexors than in knee‐extensors may depend on the different muscle morphology and coupled with a greater tolerance to fatigue in knee‐extensors. The present data add further insight to the complicated knee‐flexors‐to‐knee‐extensors strength relationship and the mechanisms behind the different occurrence of fatigue.
Discontinuity of a degenerating escape rate
Authors: DeMarco Laura , Okuyama Yûsuke
Published: May 2018

We look at degenerating meromorphic families of rational maps on

P

1

\mathbb {P}^1

—holomorphically parameterized by a punctured disk—and we provide examples where the bifurcation current fails to have a bounded potential in a neighborhood of the puncture. This is in contrast to the recent result of Favre-Gauthier that we always have continuity across the puncture for families of polynomials; and it provides a counterexample to a conjecture posed by Favre in 2016. We explain why our construction fails for polynomial families and for families of rational maps defined over finite extensions of the rationals

Q

\mathbb {Q}

.
Cyclic nucleotide signaling in Mycobacterium tuberculosis: an expanding repertoire
Authors: Johnson Richard M , McDonough Kathleen A
Published: May 2018

Mycobacterium tuberculosis (Mtb) is one of the most successful microbial pathogens, and currently infects over a quarter of the world's population. Mtb's success depends on the ability of the bacterium to sense and respond to dynamic and hostile environments within the host, including the ability to regulate bacterial metabolism and interactions with the host immune system. One of the ways Mtb senses and responds to conditions it faces during infection is through the concerted action of multiple cyclic nucleotide signaling pathways. This review will describe how Mtb uses cyclic AMP, cyclic di-AMP and cyclic di-GMP to regulate important physiological processes, and how these signaling pathways can be exploited for the development of novel thereapeutics and vaccines.
In vitro Safety and Efficacy of Lavender Essential Oil (Lamiales: Lamiaceae) as an Insecticide Against Houseflies (Diptera: Muscidae) and Blowflies (Diptera: Calliphoridae)
Authors: Cossetin Luciana F , Santi Eduarda Maria T , Cossetin Jocelene F , Dillmann Janaína B , Baldissera Matheus D , Garlet Quelen I , de Souza Tiago P , Loebens Luiza , Heinzmann Berta M , Machado Michel M , Monteiro Silvia G
Published: May 2018

Essential oils are considered an alternative for replacement of conventional insecticides that have provoked an increasing number of resistant species and damages to health. The objective of this work was to investigate the insecticidal activity of Lavandula dentata L. (Lamiales: Lamiaceae) oil against the species Musca domestica L. (Diptera: Muscidae) and Chrysomya albiceps Wiedemann (Diptera: Calliphoridae). Extraction of the essential oil from the aerial parts of the plant was carried out using hydro-distillation. Its principal compounds (1,8-cineol, camphor, and linalool oxide) were identified. Insecticidal activity was determined by evaluating adulticidal effect using topical application methods and exposure to impregnated paper; larvicidal effect was determined using immersion method. The essential oil presented toxicity in M. domestica and C. albiceps adults; the lethal concentration values (LC50) in the superficial application method were respectively 3.13 ± 0.64 and 1.39 ± 0.19% live weight (l/v). Toxicity was also found in the oil impregnated paper exposure test; the LC50 results for M. domestica and C. albiceps were respectively 4.15 ± 0.64 and 5.14 ± 0.81%. Larvicidal effect was observed on third stage M. domestica larvae when exposed to an oil concentration of 2.5% (m/v). In addition, the oil was evaluated for cytotoxicity, mutagenicity, and genotoxicity in human cells, and the in vitro safety of this oil in human cells was verified. Thus, L. dentata oil presented insecticidal activity in M. domestica and C. albiceps and can be used as an alternative for control of these dipterans.
Cerebral Oximetry for Detecting High-mortality Risk Patients with Cryptococcal Meningitis
Authors: Diehl John W , Hullsiek Katherine H , Okirwoth Michael , Stephens Nicole , Abassi Mahsa , Rhein Joshua , Meya David B , Boulware David R , Musubire Abdu K ,   ASTRO-CM Trial Team, Mpoza Edward , Kiggundu Reuben , Tugume Lillian , Ssebambulidde Kenneth , Akampurira Andrew , Kirumira Paul , Williams Darlisha A , Ndyetukira Jane Francis , Ahimbisibwe Cynthia , Kugonza Florence , Namuju Carolyne , Sadiq Alisat , Kandole Tadeo Kiiza , Luggya Tony , Kaboggoza Julian , Laker Eva , Namudde Alice , Lofgren Sarah , Kwizera Richard , Nielsen Kirsten , Stadelman Anna , Bangdiwala Ananta S
Published: May 2018

Background

Cryptococcus is the commonest cause of adult meningitis in Africa, with 50%–70% experiencing increased intracranial pressure. Cerebral oximetry is a noninvasive near-infrared spectroscopy technology to monitor percent regional cerebral tissue oxygenation (rSO2). We assessed if cerebral oximetry predicts meningitis mortality.

Methods

We performed cerebral oximetry within 14 days of cryptococcal meningitis diagnosis on 121 Ugandans from April 2016 to September 2017. We evaluated baseline rSO2 association with mortality by multivariable logistic regression and correlation with other clinical factors. We compared groups formed by initial rSO2 <30% vs ≥30% for longitudinal change with mixed effects models. We measured change in %rSO2 before and after lumbar puncture (LP).

Results

The median initial rSO2 (interquartile range) was 36% (29%–42%), and it was <30% in 29% (35/121). For 30-day mortality, the unadjusted odds ratio (per 5% increase in rSO2) was 0.73 (95% confidence interval [CI], 0.58 to 0.91; P = .005). Those with initial rSO2 <30% had 3.4 (95% CI, 1.5 to 8.0) higher odds of 30-day mortality than those with initial rSO2 ≥30%. Hemoglobin correlated with initial rSO2 (rho = .54; P < .001), but rSO2 did not correlate with pulse oximetry, intracranial pressure, cerebral perfusion pressure, or quantitative cerebrospinal fluid culture, and rSO2 was unchanged pre/post–lumbar punctures. The longitudinal rSO2 measurements change was 15% (95% CI, 12% to 18%) lower in the group with initial rSO2 <30%.

Conclusions

Individuals with cryptococcal meningitis and low cerebral oximetry (rSO2 < 30%) have high mortality. Cerebral oximetry may be useful as a prognostic marker of mortality. Targeted interventions to improve rSO2 should be tested in trials to try to decrease mortality in meningitis.
Patient satisfaction with sleep study experience: findings from the Sleep Apnea Patient-Centered Outcomes Network
Authors: Kapur Vishesh K , Johnston James C , Rueschman Michael , Bakker Jessie P , Donovan Lucas M , Hanson Mark , Harrington Zinta , Weng Jia , Redline Susan
Published: May 2018

Study Objectives

Home sleep apnea testing (HSAT) is increasingly used as an alternative to laboratory-based polysomnography (PSG) for the diagnosis of obstructive sleep apnea. Patient satisfaction with sleep testing performed at home or in the lab has been sparsely assessed, despite its potentially pivotal role in determining patients’ acceptance of sleep apnea treatment. We hypothesize that satisfaction in clinical practice may differ from what has been previously reported within the research setting.

Methods

We analyzed survey data including responses to questions regarding diagnostic sleep study type and sleep study experience satisfaction from 2563 sleep apnea patients enrolled in the Sleep Apnea Patient-Centered Outcomes Network.

Results

Patients (mean age 57 years; 54% male) who underwent in-lab PSG were more likely to be satisfied with their study experience than patients who had a HSAT (71% vs 60%; p < 0.01). Furthermore, the 38 per cent diminished odds of satisfaction in patients having HSAT (OR: 0.62; 95% CI: 0.49–0.77) persisted after adjustment for potential confounders (OR: 0.41, 95% CI; 0.27–0.63). Greater sleep apnea symptom burden and satisfaction with CPAP therapy were associated with greater study satisfaction. Effect modifications on study types by college degree education and tiredness as a study trigger were detected.

Conclusions

Patients receiving care in the community who underwent PSG reported greater satisfaction with study experience than patients who underwent HSAT in contrast to findings from randomized controlled trials. Our findings, based on data from contemporary “real-world” settings, suggest that assumptions about the generalizability of early reports comparing in-lab PSG to home-based paradigms need to be revisited.
A Travesty of Justice: Non-Compliance with the Automatic Review Mechanism for Sentences in Malawi
Authors: Gumboh Esther
Published: May 2018

Section 15 of the Criminal Procedure and Evidence Code provides a fascinating automatic review mechanism. It requires the automatic review of sentences which exceed certain thresholds by the High Court and prohibits the continued detention of prisoners once the period of automatic review has lapsed. Due to delays in the review process, most sentences that are subject to automatic review are not reviewed timeously. However, the Malawi Prison Service does not release the offenders concerned as required by law, resulting in the unlawful detention of offenders whose sentences have technically expired. The Judiciary also fails to rectify this problem by reviewing sentences outside the automatic review period. This article examines the proper interpretation of section 15 and its consequences for the revisionary powers of the High Court with a view to highlight the incorrectness of the current approach.
Phylogenetic Assignment of Ralstonia pseudosolanacearum (Ralstonia solanacearum Phylotype I) Isolated from Rosa spp.
Authors: Bergsma-Vlami M. , van de Bilt J. L. J. , Tjou-Tam-Sin N. N. A. , Westenberg M. , Meekes E. T. M. , Teunissen H. A. S. , Van Vaerenbergh J.
Published: May 2018

During the last two years, greenhouse cultivation of rose (Rosa spp.) in the Netherlands has been challenged by an uncommon bacterial disease. Affected plants suffered from chlorosis, stunting, wilting, and necrosis. The bacterial isolates obtained from the different Rosa spp. cultivars were all identified as phylotype I, sequevar 33 from the ‘Ralstonia solanacearum species complex’ (RSSC), actually reclassified as Ralstonia pseudosolanacearum. The work in this paper considers the genetic diversity and the phylogenetic position of 129 R. pseudosolanacearum isolates from the outbreak. This was assessed by AFLP based on four different primer combinations and MLP using partial sequences of the egl, mutS, and fliC genes. The AFLP revealed identical profiles for all the isolates, irrespective of their association with Rosa sp. propagating material, Rosa spp. plants for cut flowers, or water used in the different greenhouse cultivations. These AFLP profiles were unique and diverged from profiles of all other reference isolates in the RSSC included. Furthermore, MLP on egl, fliC, and mutS gene sequences clearly demonstrated that all R. pseudosolanacearum isolates clustered in phylotype I, as a distinct monophyletic group. Interestingly, this monophyletic group also included phylotype I strain Rs-09-161 from eggplant (Solanum melongena), isolated in 2009 in India. AFLP and MLP were both efficient in revealing the genetic divergence from the RSSC isolates included. The phylogenetic tree constructed from the AFLP profiles was, in general, in agreement with the one obtained from MLP. Both phylogenetic trees displayed a similar clustering, supported by high posterior probabilities. Both methodologies clearly demonstrated that the R. pseudosolanacearum isolates from Rosa spp. grouped in a monophyletic group inside phylotype I, with a particular correspondence to a strain present in India, as revealed in MLP.
Salmonella enterica serovar Typhimurium isolated from the urine of a dog undergoing treatment for immune-mediated polyarthritis
Authors: Cole Stephen D. , Palermo Shannon M. , Rankin Shelley C.
Published: May 2018

Introduction. In people, Salmonella is a common agent of gastroenteritis, but it can also cause extraintestinal disease such as urinary tract infections. In addition, Salmonella is often linked to the post-infection development of reactive arthritis. In canines, cases that document extraintestinal Salmonella infections or diseases similar to reactive arthritis have not been thoroughly described.

Case presentation. A case of a 5-year-old German shepherd dog with Salmonella bacteriuria during treatment for immune-mediated polyarthritis (IMPA) is described. The patient first suffered from a 3 month period of diarrhoea and presented for evaluation of a 2 month history of shifting-leg lameness. A diagnosis of IMPA was made based on cytological examination and negative synovial fluid culture. Treatment with immunosuppressive doses of prednisone lead to clinical resolution of lameness, but on a recheck abnormal urine was noted. Salmonella enterica serovar Typhimurium was isolated using standard culture methods. The patient was treated with enrofloxacin to control the bacteriuria.

Conclusion. This case report is, to the best of our knowledge, the first to describe Salmonella bacteriuria in a dog and suggests that Salmonella infection may be a potential inciting factor for IMPA.
A High-throughput Neurohistological Pipeline for Brain-Wide Mesoscale Connectivity Mapping of the Common Marmoset
Authors: Lin Meng Kuan , Takahashi Yeonsook Shin , Huo Bing-Xing , Hanada Mitsutoshi , Nagashima Jaimi , Hata Junichi , Tolpygo Alexander S. , Ram Keerthi , Lee Brian , Miller Michael , Rosa Marcello G.P. , Sasaki Erika , Iriki Atsushi , Okano Hideyuki , Mitra Partha P.
Published: May 2018

Understanding the connectivity architecture of entire vertebrate brains is a fundamental but difficult task. MRI based methods offer whole brain coverage, but remain indirect in the approach to connectivity mapping. Recent progress has been made in directly mapping whole-brain connectivity architecture in the mouse at the mesoscopic scale. The basic approach uses tracer injections systematically placed on a grid of locations spanning the brain and computational analysis of the resulting whole brain data sets. Scaling this approach to bigger primate brains poses nontrivial technical challenges. Here we present an integrated neurohistological pipeline as well as a grid-based tracer injection strategy for systematic mesoscale connectivity mapping in the common Marmoset (Callithrix jacchus). Individual brains are sectioned into ∼1700 20µm sections using the tape transfer technique, permitting high quality 3D reconstruction of a series of histochemical stains (Nissl, myelin) interleaved with tracer labelled sections. Combining the resulting 3D volumes, containing informative cytoarchitectonic markers, within-vivoandex-vivoMRI, and using an integrated computational pipeline, we are able to overcome the significant individual variation exhibited by Marmosets to obtain routine and high quality maps to a common atlas framework. This will facilitate the systematic assembly of a mesoscale connectivity matrix together with unprecedented 3D reconstructions of brain-wide projection patterns in a primate brain. While component instruments or protocols may be available from previous work, we believe that this is the first detailed systems-level presentation of the methodology required for high-throughput neuroanatomy in a model primate.
Multilabel multiclass classification of OCT images augmented with age, gender and visual acuity data
Authors: Mehta Parmita , Lee Aaron , Lee Cecilia , Balazinska Magdalena , Rokem Ariel
Published: May 2018

Optical Coherence Tomography (OCT) imaging of the retina is in widespread clinical use to diagnose a wide range of retinal pathologies and several previous studies have used deep learning to create systems that can accurately classify retinal OCT as indicative of one of these pathologies. However, patients often exhibit multiple pathologies concurrently. Here, we designed a novel neural network algorithm that performs multiclass and multilabel classification of retinal images from OCT images in four common retinal pathologies: epiretinal membrane, diabetic macular edema, dry age-related macular degeneration and neovascular age-related macular degeneration. Furthermore, clinicians often also use additional information about the patient for diagnosis. Second contribution of this study is improvement of multiclass, multilabel classification augmented with information about the patient: age, visual acuity and gender. We compared two training strategies: a network pre-trained with ImageNet was used for transfer learning, or the network was trained from randomly initialized weights. Transfer learning does not perform better in this case, because many of the low-level filters are tuned to colors, and the OCT images are monochromatic. Finally, we provide a transparent and interpretable diagnosis by highlighting the regions recognized by the neural network.
A Composition-Dependent Molecular Clutch Between T Cell Signaling Condensates and Actin
Authors: Ditlev J.A. , Vega A.R. , Köster D.V. , Su X. , Tani T. , Lakoduk A.M. , Vale R.D. , Mayor S. , Jaqaman K. , Rosen M.K.
Published: May 2018

Biomolecular condensates play important roles in eukaryotic cells by concentrating molecules into foci without a surrounding membrane. During T cell activation, biomolecular condensates form at the immunological synapse (IS) through multivalency-driven phase separation of the adaptor protein LAT and its binding partners Grb2, Sos1, SLP-76, Nck and WASP. These condensates move radially at the IS, traversing a radially-oriented and then a concentric actin network. To understand the persistent radial movement, we biochemically reconstituted LAT condensates with mobile actomyosin filaments. We found that basic regions of Nck and N-WASP promote strong association and co-movement of LAT condensates with actin. Condensates lacking these components were instead propelled by steric interactions. In cells, LAT condensates lost Nck while traversing the boundary between the two actin networks, and condensates engineered to constitutively bind actin moved aberrantly. We propose that Nck and WASP form a clutch between LAT condensates and actin, and changes in composition enable condensate movement by distinct actin networks in different regions of the IS.
Immediate stimulus repetition abolishes stimulus expectation and surprise effects in fast periodic visual oddball designs
Authors: Feuerriegel Daniel , Keage Hannah A. D. , Rossion Bruno , Quek Genevieve L.
Published: May 2018

Oddball designs are widely used to investigate the sensitivity of the visual system to statistical regularities in sensory environments. However, the underlying mechanisms that give rise to visual mismatch responses remain unknown. Much research has focused on identifying separable, additive effects of stimulus repetition and stimulus appearance probability (expectation/surprise) but findings from non-oddball designs indicate that these effects also interact. We adapted the fast periodic visual stimulation (FPVS) unfamiliar face identity oddball design (Liu-Shuang et al., 2014) to test for both additive and interactive effects of stimulus repetition and stimulus expectation. In two experiments, a given face identity was presented at a 6 Hz periodic rate; a different identity face (the oddball) appeared as every 7th image in the sequence (i.e., at 0.857 Hz). Electroencephalographic (EEG) activity was recorded during these stimulation sequences. In Experiment 1, we tested for surprise responses evoked by unexpected face image repetitions by replacing 10% of the commonly-presented oddball faces with exact repetitions of the base rate face identity image. In Experiment 2, immediately repeated or unrepeated face identity oddballs were presented in high and low presentation probability contexts (i.e., expected or surprising), allowing assessment of expectation effects on responses to both repeated and unrepeated stimuli. Across both experiments objective (i.e., frequency-locked) visual mismatch responses driven by stimulus expectation were only found for oddball faces of a different identity to base rate faces (i.e., unrepeated identity oddballs). Our results show that immediate stimulus repetition (i.e., repetition suppression) can reduce or abolish expectation effects as indexed by EEG responses in visual oddball designs.

Highlights

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We studied visual mismatch responses with a fast periodic oddball design

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Our design cleanly separates immediate stimulus repetition and expectation effects

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Stimulus expectation effects were only present for unrepeated stimuli

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Immediate stimulus repetition reduced EEG expectation effects
Identification, structure-activity relationship andin silicomolecular docking analyses of five novel angiotensin I-converting enzyme (ACE)-inhibitory peptides from stone fish hydrolysates
Authors: Auwal Shehu Muhammad , Zainal Abidin Najib , Zarei Mohammad , Tan Chin Ping , Saari Nazamid
Published: May 2018

Stone fish is an under-utilized sea cucumber with many health benefits. Hydrolysates with strong ACE-inhibitory effects were generated from stone fish protein under the optimum conditions of hydrolysis using bromelain and fractionated based on hydrophobicity and isoelectric properties of the constituent peptides. Five novel peptide sequences with molecular weight (mw) < 1000 daltons (Da) were identified using LC-MS/MS. The peptides including ALGPQFY (794.44 Da), KVPPKA (638.88 Da), LAPPTM (628.85 Da), EVLIQ (600.77 Da) and EHPVL (593.74 Da) were evaluated for ACE-inhibitory activity and showed IC50values of 0.012 mM, 0.980 mM, 1.31 mM, 1.44 mM and 1.68 mM, respectively. The ACE-inhibitory effects of the peptides were further verified using molecular docking study. The docking results demonstrated that the peptides exhibit their effect mainly via hydrogen and electrostatic bond interactions with ACE. These findings provide evidence about stone fish as a valuable source of raw materials for the manufacture of antihypertensive peptides that can be incorporated to enhance therapeutic relevance and commercial significance of formulated functional foods.
Omitted variable bias in GLMs of neural spiking activity
Authors: Stevenson Ian H.
Published: May 2018

Generalized linear models (GLMs) have a wide range of applications in systems neuroscience describing the encoding of stimulus and behavioral variables as well as the dynamics of single neurons. However, in any given experiment, many variables that impact neural activity are not observed or not modeled. Here we demonstrate, in both theory and practice, how these omitted variables can result in biased parameter estimates for the effects that are included. In three case studies, we estimate tuning functions for common experiments in motor cortex, hippocampus, and visual cortex. We find that including traditionally omitted variables changes estimates of the original parameters and that modulation originally attributed to one variable is reduced after new variables are included. In GLMs describing single-neuron dynamics, we then demonstrate how post-spike history effects can also be biased by omitted variables. Here we find that omitted variable bias can lead to mistaken conclusions about the stability of single neuron firing. Omitted variable bias can appear in any model with confounders – where omitted variables modulate neural activity and the effects of the omitted variables covary with the included effects. Understanding how and to what extent omitted variable bias affects parameter estimates is likely to be important for interpreting the parameters and predictions of many neural encoding models.
Adventitious viruses persistently infect three commonly used mosquito cell lines
Authors: Weger-Lucarelli James , Rückert Claudia , Grubaugh Nathan D. , Misencik Michael J. , Armstrong Philip M. , Stenglein Mark D. , Ebel Gregory D. , Brackney Doug E.
Published: May 2018

Mosquito cell lines were first established in the 1960’s and have been used extensively in research to isolate and propagate arthropod-borne (arbo-) viruses, study the invertebrate immune system, and understand virus-vector interactions. Despite their utility as anin vitrotool, these cell lines are poorly defined and may harbor insect-specific viruses that could impact experimental results. Accordingly, we screened four commonly-used mosquito cell lines, C6/36 and U4.4 cells fromAedes albopictus, Aag2 cells fromAedes aegypti, and Hsu cells fromCulex quinquefasciatus, for the presence of adventitious viruses. All four cell lines stained positive for double-stranded RNA by immunofluorescence, indicative of RNA virus replication. We subsequently identified viruses infecting Aag2, U4.4 and Hsu cell lines using untargeted next-generation sequencing, but not C6/36 cells. Sequences from viruses in the familiesBirnaviridae,Bunyaviridae, Flaviviridae,andRhabdoviridaewere abundant in the mosquito cell lines. PCR confirmation revealed that these sequences stem from active viral replication and/or integration into the cellular genome. Our results show that these commonly-used mosquito cell lines are persistently-infected with several viruses. This finding may be critical to interpreting data generated in these systems.
Determinants of livelihood choices and artisanal entrepreneurship in Nigeria
Authors: Igwe Paul Agu , Madichie Nnamdi O. , Newbery Robert
Published: May 2018

Purpose

The purpose of this paper is to provide fresh insights into rural artisanal activities in a developing world context. It highlights key determinants of the decision to engage in an artisanal business and the challenges that impact upon the growth of these activities.

Design/methodology/approach

The study adopts a mix-method research approach to explore a rural setting where most respondents (81 per cent) combine farm and non-farm livelihood activities. Quantitatively, a multi-nominal regression is used to examine the determinants of diversified artisanal livelihoods. It modelled the differences between farming livelihoods that have not diversified, compared to those also involved in the artisanal activity or wage employment and the intensity of participation.

Findings

The findings show that nearly half of artisanal businesses (45.4 per cent) comprise only the owners and no employee, while 54.6 per cent employ one to three workers. Also, some artisanal ventures were more gender-specific than the gender-neutral activities. Other observations were in age (most artisans were under the age of 46 years) and vocational training (most were self-trained followed by a third receiving training only in specific areas such as technical works, building and construction and general trading apprenticeships).

Research limitations/implications

The study is based on a relatively small sample size of 306 business owners, which makes it difficult to generalise despite the persuasiveness of the observations made.

Practical implications

First, the use of econometric methods enabled the development of valid data sets (and various descriptive statistical and logit regression) to analyse determinants of the decision to engage in artisanal work, and the intensity of participation. Second, the ambiguity in categorising artisanal activities is unravelled. The study characterises the local artisanal sector and examines the intensity of participation. Without these, targeted support would remain elusive for practical and policy interventions.

Originality/value

Artisanal activities constitute a high proportion of small businesses in the study area – with more than half (54.2 per cent) of respondents being classified as artisans, yet it is an overlooked area of entrepreneurship. Highlighted here are both types of activities and challenges regarding better conceptualising the understanding of artisans and regarding this mostly unarticulated base of practice.
The impact of overseas human capital and social ties on Chinese returnee entrepreneurs’ venture performance
Authors: Ma Zhenzhong , Zhu Jinwei , Meng Yong , Teng Ying
Published: May 2018

Purpose

Entrepreneurship research clearly documents the importance of human and social capital and stresses the way in which entrepreneurs take advantage of their own social affiliations and network strategies in pursuit of their entrepreneurial goals, yet the research on returnee entrepreneurs’ human and social capital is not sufficiently studied in the international context, in particular when returnees’ overseas human capital and social capital may be a misfit with local business environment. Using the data from Chinese returnee entrepreneurs’ venture activities in China, the purpose of this paper is to examine the impact of returnee entrepreneurs’ overseas capital (human and social) and domestic capital (human and social) on their venture performance in China, and further explore the interaction effect of different social and human capital with China’s entrepreneurial environment.

Design/methodology/approach

This study surveyed 500 start-up businesses created by returnee entrepreneurs in China to collect data. Self-administered questionnaires were used to collect data on their demographic information, the information about the human and social capital of these returnee entrepreneurs, including domestic and overseas capital, various performance measures, and other control variables ending up with 226 usable questionnaires.

Findings

The results show that Chinese returnee entrepreneurs’ overseas human capital and social capital, as well as their domestic social capital, but not domestic human capital, have a significant impact on their venture performance. In addition, while domestic entrepreneurial environment does not affect the impact of overseas human and social capital on venture performance, it does provide an important contextual setting for domestic capital to improve returnee entrepreneurs’ venture performance.

Originality/value

The findings help enrich the understanding of the dynamic interplays among Chinese returnee entrepreneurs’ domestic human capital and social capital, overseas human capital, and social capital, as well as the entrepreneurial environment for returnee entrepreneurs’ success, which makes an important contribution to the international entrepreneurship theory by showing that overseas human capital and social capital are not a misfit with local markets. It also provides empirical support for the mediating effect of entrepreneurial opportunity identification. The important role of entrepreneurial opportunity is empirically supported in an international context: entrepreneurship is all about the discovery of entrepreneurial opportunities and exploitation of this opportunity to create viable business entities for new products and services, even in the Chinese context, a culture which is very different from the ones where the entrepreneurship theory was developed.
Cultural configurations and entrepreneurial realisation
Authors: Torres Pedro , Augusto Mário
Published: May 2018

Purpose

The purpose of this paper is to better understand the connection between culture and entrepreneurship in proposing and testing complex configurations of culturally endorsed implicit leadership theories (CLTs) and cultural practices that lead to entrepreneurial behaviour by studying entrepreneurial intentions (EI) and early-stage entrepreneurial activity (TEA) separately.

Design/methodology/approach

Using data from Globe Leadership and Organizational Behavior Effectiveness (GLOBE) and Global Entrepreneurship Monitor (GEM) studies, a sample of 44 countries, and a fuzzy-set qualitative comparative analysis, several models for EI and TEA were developed.

Findings

The main findings provide a way of distinguishing between complex antecedent conditions that are required for each stage of the entrepreneurial realisation. The results empirically show that there is no ideal context – the path to stimulate entrepreneurship that works best for one country does not necessarily works the same for other countries. There are multiple paths to achieve the desired outcome.

Research limitations/implications

The data from the GLOBE study were not completely up to date, the effect of which was minimised by considering data from GEM that respects temporal ordering. Nevertheless, data from GEM suggest that there is a degree of stability in the data over time. Future research could replicate this study with a larger selection of countries and with new data, collected in a different way. Additionally, the inclusion of CLTs proposed in this study opens new opportunities for future research, by providing a new angle to look at the entrepreneurial realisation process.

Practical implications

This study advances research into the association of culture and entrepreneurship, and develops testable models using a configurational approach, thus confirming the suitability of asymmetric configuration analysis for entrepreneurial research. The results expand an understanding of the entrepreneurial process by showcasing the different complex antecedent conditions for EI and TEA. Depending on a country’s cultural profile, policy-makers should invest in the dimensions that enable their society to align with the model that best suits their own culture. The obtained models offer a framework for evaluating new interventions that aim to develop entrepreneurial behaviour in a specific country.

Originality/value

Different configurations showcase that there are alternative paths to achieving high levels of EI and TEA. The differences among the possible configurations for each stage of the entrepreneurial realisation are uncovered. Country profiles are identified, quantified, and then compared providing guidance for policy-makers.
Does product design matter? Exploring its influences in consumers’ psychological responses and brand loyalty
Authors: Hsu Chia-Lin , Chen Yen-Chun , Yang Tai-Ning , Lin Wei-Ko , Liu Yi-Hsuan
Published: May 2018

Purpose

Unique product design is a highlight of sustainable branding. The purpose of this paper is to investigate whether product design affects customers’ psychological responses (i.e. cognitive and affective responses) to smartphones, and, in turn, affects their brand loyalty (i.e. attitudinal and behavioral brand loyalty), further advancing the knowledge of product design and brand management.

Design/methodology/approach

This work used survey data from 456 Taiwanese with experience using smartphone. Structural equation modeling was employed to test the proposed model and hypotheses.

Findings

The results indicate that the product design significantly affects both cognitive response and affective response, which, in turn, significantly affect both attitudinal brand loyalty and behavioral brand loyalty. The findings also suggest that the moderating effect of product involvement on the relationship between product design and affective response is statistically significant, although it does not positively and significantly moderate the link between product design and cognitive response.

Research limitations/implications

This study has two main limitations. First, this study was conducted in the context of smartphones, thus potentially constraining the generalization of the results to other industries. Second, the data in this study were obtained from a cross-sectional design.

Practical implications

These findings can permit companies to generate more brand loyalty in their customers and guide their management of assets and marketing activities.

Originality/value

This paper presents new insights into the nature and importance of product design in brand value.
Mapping knowledge structure by keyword co-occurrence and social network analysis
Authors: Cheng Fei-Fei , Huang Yu-Wen , Yu Hsin-Chun , Wu Chin-Shan
Published: May 2018

Purpose

The purpose of this paper is to present the knowledge structure based on the articles published in Library Hi Tech. The research hotspots are expected to be revealed through the keyword co-occurrence and social network analysis.

Design/methodology/approach

Data sets based on publications from Library Hi Tech covering the time period from 2006 to 2017 were extracted from Web of Science and developed as testbeds for evaluation of the CiteSpace system. Highly cited keywords were analyzed by CiteSpace which supports visual exploration with knowledge discovery in bibliographic databases.

Findings

The findings suggested that the percentage of publications in the USA, Germany, China, and Canada are high. Further, the most popular keywords identified in Library Hi Tech were: “service,” “technology,” “digital library,” “university library,” and “academic library.” Finally, four research issues were identified based on the most-cited articles in Library Hi Tech.

Originality/value

While keyword plays an important role in scientific research, limited studies paid attention to the keyword analysis in librarian research. The contribution of this study is to systematically explore the knowledge structure constructed by the keywords in Library Hi Tech.
The impacts of deviations from standard daily procedures on stock performance – a case study of Carnival Cruise Line
Authors: Wang Grace , Zeng Qingcheng , Ghoram Lawrence Cliff
Published: May 2018

Purpose

In the USA, the cruise industry has generated more than $42bn in total economic activities, involving over 356,000 jobs. The largest and most aggressive operator is acknowledged as Carnival Cruise Line (CCL), with a 48.3 per cent market share including all subsidiary companies in 2013. CCL has had a strong track record of reliability and high quality; however, within the past decade, there have been several deviations from standard daily procedure that have altered the way CCL does business. When trying to interpret changes in company performance, it is important to include other factors that may have contributed to changes at the time of any given deviation.

Design/methodology/approach

The authors use time series empirical mode decomposition to visualize whether there are short- or long-term shocks to company performance in the wake of deviating events. Besides, a thorough analysis is carried out with multivariable linear regression to identify the factors that really impact CCL’s performance.

Findings

This case study shows the seasonal patterns of weather issues with the largest number of hurricanes and tropical storms taking place during the third quarter of each year.

Originality/value

Empirical results will enhance understanding of the industry with regard to such events. It will provide shareholders information and opinions to enhance their decision-making processes.