bluuebunny/crossref_metadata_2025 huggingface dataset:
Exfoliated transition metal dichalcogenide nanosheets for supercapacitor and sodium ion battery applications
Authors: Mukherjee Santanu , Turnley Jonathan , Mansfield Elisabeth , Holm Jason , Soares Davi , David Lamuel , Singh Gurpreet
Published: August 2019

Growing concerns regarding the safety, flammability and hazards posed by Li-ion systems have led to research on alternative rechargeable metal-ion electrochemical storage technologies. Among the most notable of these are Na-ion supercapacitors and batteries, motivated, in part, by the similar electrochemistry of Li and Na ions. However, sodium ion batteries (SIBs) come with their own set of issues, especially the large size of the Na
+
ion, its relatively sluggish kinetics and low energy densities. This makes the development of novel materials and appropriate electrode architecture of absolute significance. Transition metal dichalcogenides (TMDs) have attracted a lot of attention in this regard due to their relative ease of exfoliation, diverse morphologies and architectures with superior electronic properties. Here, we study the electrochemical performance of Mo-based two-dimensional (2D) layered TMDs (e.g. MoS
2
, MoSe
2
and MoTe
2
), exfoliated in a superacid, for battery and supercapacitor applications. The exfoliated TMD flakes were interfaced with reduced graphene oxide (rGO) to be used as composite electrodes. Electron microscopy, elemental mapping and Raman spectra were used to analyse the exfoliated material and confirm the formation of 2D TMD/rGO layer morphology. For supercapacitor applications in aqueous electrolyte, the sulfide-based TMD (MoS
2
) exhibited the best performance, providing an areal capacitance of 60.25 mF cm
−2
. For SIB applications, TMD electrodes exhibited significantly higher charge capacities than the neat rGO electrode. The initial desodiation capacities for the composite electrodes are 468.84 mAh g
−1
(1687.82 C g
−1
), 399.10 mAh g
−1
(1436.76 C g
−1
) and 387.36 mAh g
−1
(1394.49 C g
−1
) for MoS
2
, MoSe
2
and MoTe
2
, respectively. Also, the MoS
2
and MoSe
2
composite electrodes provided a coulombic efficiency of near 100 % after a few initial cycles.
Liquid chromatography–tandem mass spectrometry metabolic profiling of nazartinib reveals the formation of unexpected reactive metabolites
Authors: Abdelhameed Ali S. , Attwa Mohamed W. , Kadi Adnan A.
Published: August 2019

Nazartinib (EGF816, NZB) is a promising third-generation human epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor. This novel irreversible mutant-selective EGFR inhibitor targets EGFR containing both the resistance mutation (T790M) and the activating mutations (L858R and Del19), while it does not affect wild-type EGFR. However, the metabolic pathway and bioactivation mechanisms of NZB are still unexplored. Thus, using liquid chromatography–tandem mass spectrometry, we screened for products of NZB metabolism formed
in vitro
by human liver microsomal preparations and investigated the formation of reactive intermediates using potassium cyanide as a nucleophile trap. Unexpectedly, the azepane ring was not bioactivated. Instead, the carbon atom between the aliphatic linear tertiary amine and electron-withdrawing system (butenoyl amide group) was bioactivated, generating iminium intermediates as reactive species. Six NZB phase I metabolites, formed by hydroxylation, oxidation and
N
-demethylation, were characterized. Moreover, two reactive iminium ions were characterized and their corresponding bioactivation mechanisms were proposed. Based on our results, we speculate that bioactivation of NZB can be blocked by small sterically hindering groups, isosteric replacement or a spacer. This approach might reduce the toxicity of NZB by avoiding the generation of reactive species.
Insect brain plasticity: effects of olfactory input on neuropil size
Authors: Eriksson Maertha , Nylin Sören , Carlsson Mikael A.
Published: August 2019

Insect brains are known to express a high degree of experience-dependent structural plasticity. One brain structure in particular, the mushroom body (MB), has been attended to in numerous studies as it is implicated in complex cognitive processes such as olfactory learning and memory. It is, however, poorly understood to what extent sensory inputper seaffects the plasticity of the mushroom bodies. By performing unilateral blocking of olfactory input on immobilized butterflies, we were able to measure the effect of passive sensory input on the volumes of antennal lobes (ALs) and MB calyces. We showed that the primary and secondary olfactory neuropils respond in different ways to olfactory input. ALs show absolute experience-dependency and increase in volume only if receiving direct olfactory input from ipsilateral antennae, while MB calyx volumes were unaffected by the treatment and instead show absolute age-dependency in this regard. We therefore propose that cognitive processes related to behavioural expressions are needed in order for the calyx to show experience-dependent volumetric expansions. Our results indicate that such experience-dependent volumetric expansions of calyces observed in other studies may have been caused by cognitive processes rather than by sensory input, bringing some causative clarity to a complex neural phenomenon.
Optimization of the microwave-assisted extraction characteristics for bioactive compounds from eggplant (Solanum melongena L.)
Authors: Gu Song-Yi , Jo Yunhee , Ameer Kashif , Kwon Joong-Ho
Published: August 2019

Eggplant is consumed worldwide as a valuable source of phytochemicals, especially anthocyanin and antioxidants. Here, microwave-assisted extraction (MAE) was applied to optimize the total yield (TY), total anthocyanin content (TAC), total phenolic content (TPC), and radical scavenging activities (DPPH, ABTS, and FRAP) of eggplant. A response surface methodology (RSM) was employed based on a five-factor, three-level central composite design with the ethanol concentration (X1) 55-95% , microwave power (X2: 0-200 W), and extraction time (X3: 30-150 s) as independent process variables. Furthermore, the efficiency of MAE was compared to that of conventional reflux extraction (CRE) in terms of target responses, energy consumption, and CO2 emissions. The highest TY (1.72%), TAC (9.55 mg CE/L), TPC (48.75 mg GAE/100 mL), and antioxidant activities (DPPH: 45.95, ABTS: 46.74, and FRAP: 69.22 mg TE/100 mL) were obtained under the optimum MAE parameters of X1: 70%, X2: 160 W, and X3: 100 s. Moreover, MAE yielded higher target responses than CRE in a faster time with lower energy consumption and CO2 emissions. In conclusion, the application of RSM to evaluate the extraction characteristics of individual components by MAE and CRE revealed MAE as an effective method for the green extraction of target compounds from eggplant.
Electron spin resonance spectroscopy identifies radiation-induced markers in 7 kGy-irradiated dried lavers subjected to alkaline pretreatment
Authors: Sanyal Bhaskar , Lee Eunjin , Jo Yunhee , Kim Gui-Ran , Ghosh Sunil K , Kwon Joong-Ho
Published: August 2019

Food irradiation was allowed for dried seaweeds for improving microbial quality in Korea and reliable detection methods are required for the routine control in international trade. In this study, three kinds of popular dried laver (seaweeds) were electron-beam irradiated at approved 7 kGy dose, and the radiation-induced signals were detected using electron paramagnetic resonance (ESR) spectroscopy coupled with alkaline pretreatment. The influence of conventional post-irradiation sample pretreatment such as freeze drying (FD) was also compared with that of alkaline pretreatments, i.e., NaOH extraction (NE) and KOH extraction (KE). Non-irradiated samples were characterized by their ESR spectra, having singlet g-values of g = 2.006, 7 kGy-irradiated samples with FD and KE pretreatments did not exhibit any detectable irradiation-induced signals. However, all the irradiated samples treated with NaOH showed a new radiation-induced ESR signal hfcc (hyperfine coupling constant) of 2.3 mT that is different from that of the established cellulose radicals (hfcc of 3 mT). Thus, attempts have been made to understand the origin of the new signal. The improved approach of combination treatment with NaOH and ESR spectroscopy was successful in identifying irradiated dried laver.
Continent-wide effects of urbanization on bird and mammal genetic diversity
Authors: Schmidt C. , Domaratzki M. , Kinnunen R.P. , Bowman J. , Garroway C.J.
Published: August 2019

Abstract

Urbanization and associated environmental changes are causing global declines in vertebrate populations. In general, population declines of the magnitudes now detected should lead to reduced effective population sizes for animals living in proximity to humans and disturbed lands. This is cause for concern because effective population sizes set the rate of genetic diversity loss due to genetic drift, the rate of increase in inbreeding, and the efficiency with which selection can act on beneficial alleles. We predicted that the effects of urbanization should decrease effective population size and genetic diversity, and increase population-level genetic differentiation. To test for such patterns, we repurposed and reanalyzed publicly archived genetic data sets for North American birds and mammals. After filtering, we had usable raw genotype data from 85 studies and 41,023 individuals, sampled from 1,008 locations spanning 41 mammal and 25 bird species. We used census-based urban-rural designations, human population density, and the Human Footprint Index as measures of urbanization and habitat disturbance. As predicted, mammals sampled in more disturbed environments had lower effective population sizes and genetic diversity, and were more genetically differentiated from those in more natural environments. There were no consistent relationships detectable for birds. This suggests that, in general, mammal populations living near humans may have less capacity to respond adaptively to further environmental changes, and be more likely to suffer from effects of inbreeding.
Effect of systemic treatment with N-[2-(5-hydroxy-1H-indol-3-yl)ethyl]-2-oxopiperidine-3- carboxamide (HIOC) or tauroursodeoxycholic Acid (TUDCA) on retinal ganglion cell death following optic nerve crush
Authors: Li Ying , Zhang Xian , Wang Jiaxing , Sellers Jana T. , Boyd Amber P. , Nickerson John M. , Boatright Jeffrey H.
Published: August 2019

The aim of this study was to investigate the protective effects of systemically administered N-[2-(5-hydroxy-1H-indol-3-yl)ethyl]-2-oxopiperidine-3-carboxamide (HIOC) or tauroursodeoxycholic acid (TUDCA) in an optic nerve crush (ONC) mouse model. HIOC (50 mg/kg) or TUDCA (500mg/kg) were intraperitoneally (i.p.) injected into adult C57BL/6 mice three times per week. Two weeks after treatment (6 injections), unilateral optic nerve crush was conducted followed by treatment at the same day. The treatment was continued until 1 week or 2 weeks after ONC. A control cohort was identically treated with drug vehicle (phosphate-buffered saline; PBS). Retinas were harvested for whole mount immunofluorescence staining with RGC markers and imaged by fluorescent confocal microscopy at 40x magnification. Fluorescing cells were counted by computer-assisted automated identification and counting software (CellProfiler). Cohort sampling sizes were N=4 and statistical tesing was by the Wilcoxon-Mann-Whitney Test. Significant loss (80%’85%) occurred in the PBS-injected group 1 and 2 weeks after ONC. This loss was partially but significantly prevented in drug-treated cohorts (P < 0.05). Delivery of HIOC or TUDCA by i.p. injection increased survival of RGCs after ONC. Protection was similar between treatment with either drug. These data suggest that it is worthwhile to further explore possible protective effects of HIOC or TUDCA on RGC subtypes with regards to structure and function and in additional disease models that involve RGC loss.
Related enteric viruses have different requirements for host microbiota in mice
Authors: Robinson Christopher M. , Acevedo Mikal A. Woods , McCune Broc T. , Pfeiffer Julie K.
Published: August 2019

Accumulating evidence suggests that intestinal bacteria promote enteric virus infection in mice. For example, previous work demonstrated that antibiotic treatment of mice prior to oral infection with poliovirus reduced viral replication and pathogenesis. Here we examined the effect of antibiotic treatment on infection with coxsackievirus B3 (CVB3), a picornavirus closely related to poliovirus. We treated mice with a mixture of five antibiotics to deplete host microbiota and examined CVB3 replication and pathogenesis following oral inoculation. We found that, like poliovirus, CVB3 shedding and pathogenesis were reduced in antibiotic-treated mice. While treatment with just two antibiotics, vancomycin and ampicillin, was sufficient to reduce CVB3 replication and pathogenesis, this treatment had no effect on poliovirus. Quantity and composition of bacterial communities were altered by treatment with the five antibiotic cocktail and by treatment with vancomycin and ampicillin. To determine whether more subtle changes in bacterial populations impact viral replication, we examined viral infection in mice treated with milder antibiotic regimens. Mice treated with one-tenth the concentration of the normal antibiotic cocktail supported replication of poliovirus but not CVB3. Importantly, a single dose of one antibiotic, streptomycin, was sufficient to reduce CVB3 shedding and pathogenesis, while having no effect on poliovirus shedding and pathogenesis. Overall, replication and pathogenesis of CVB3 is more sensitive to antibiotic treatment than poliovirus, indicating that closely related viruses may differ in their reliance on microbiota.

Importance

Recent data indicate that intestinal bacteria promote intestinal infection of several enteric viruses. Here we show that coxsackievirus, an enteric virus in the picornavirus family, also relies on microbiota for intestinal replication and pathogenesis. Relatively minor depletion of the microbiota was sufficient to decrease coxsackievirus infection, while poliovirus infection was unaffected. Surprisingly, a single dose of one antibiotic was sufficient to reduce coxsackievirus infection. Therefore, these data indicate that microbiota can influence enteric virus infection through distinct mechanisms, even for closely related viruses.
Physical limit to concentration sensing in a changing environment
Authors: Mora Thierry , Nemenman Ilya
Published: August 2019

Cells adapt to changing environments by sensing ligand concentrations using specific receptors. The accuracy of sensing is ultimately limited by the finite number of ligand molecules bound by receptors. Previously derived physical limits to sensing accuracy have assumed that the concentration was constant and ignored its temporal fluctuations. We formulate the problem of concentration sensing in a strongly fluctuating environment as a non-linear field-theoretic problem, for which we find an excellent approximate Gaussian solution. We derive a new physical bound on the relative error in concentration c which scales as δc/c ~ (Dacτ)−1/4 with ligand diffusivity D, receptor cross-section a, and characteristic fluctuation time scale τ, in stark contrast with the usual Berg and Purcell bound δc/c ~ (DacT)−1/2 for a perfect receptor sensing concentration during time T. We show how the bound can be achieved by a simple biochemical network downstream the receptor that adapts the kinetics of signaling as a function of the square root of the sensed concentration.
Culture of salivary methanogens assisted by chemically produced hydrogen
Authors: Guindo CO , Terrer E , Chabrière E , Aboudharam G , Drancourt M , Grine G
Published: August 2019

Methanogen cultures require hydrogen produced by fermentative bacteria such asBacteroides thetaiotaomicron(biological method). We developed an alternative method for hydrogen production using iron filings and acetic acid with the aim of cultivating methanogens more efficiently and more quickly (chemical method). We developed this new method with a reference strain ofMethanobrevibacter oralis, compared the method to the biological reference method with a reference strain ofMethanobrevibacter smithiiand finally applied the method to 50 saliva samples. Methanogen colonies counted using ImageJ software were identified using epifluorescence optical microscopy, real-time PCR and PCR sequencing. For cultures containing the pure strains ofM. oralisandM. smithii, colonies appeared three days postinoculation with the chemical method versus nine days with the biological method. The average number ofM. smithiicolonies was significantly higher with the chemical method than with the biological method. There was no difference in the delay of observation of the first colonies in the saliva samples between the two methods. However, the average number of colonies was significantly higher when using the biological method than when using the chemical method at six days and nine days postinoculation (Student’s test, p = 0.005 and p = 0.04, respectively). The chemical method made it possible to isolate four strains ofM. oralisand three strains ofM. smithiifrom the 50 saliva samples. Establishing the chemical method will ease the routine isolation and culture of methanogens.
Kcnn3 as a target for treating aberrant behaviors in stressed, ethanol-dependent mice
Authors: Padula Audrey E. , Rinker Jennifer A. , Khan Fauzan , Lopez Marcelo F. , Mulligan Megan K. , Williams Robert W. , Becker Howard C. , Mulholland Patrick J.
Published: August 2019

Anxiety and mood disorders are often comorbid with alcohol use disorder (AUD) and are considered critical in the development, maintenance, and reinstatement of alcohol dependence and harmful alcohol-seeking behaviors. Because of this high comorbidity, it is necessary to determine shared and unique genetic factors driving heavy ethanol drinking and anxiety-related behaviors. We used a model of stress-induced escalation of drinking in ethanol dependent C57BL/6J mice to measure anxiety-like behaviors on the marble burying and novelty-suppressed feeding task (NSFT) during abstinence. In order to identify novel pharmacogenetic targets that may lead to more effective treatment, a targeted bioinformatics analysis was used to quantify the expression of K+ channel genes in the amygdala that covary with anxiety-related phenotypes in the well phenotyped and fully sequenced family of BXD strains. A pharmacological approach was used to validate the key bioinformatics finding in ethanol-dependent, stressed C57BL/6J mice during the NSFT. Amygdalar expression of Kcnn3 correlated significantly with just over 40 anxiety-associated phenotypes. Further examination of Kcnn3 expression revealed a strong eigentrait for anxiety-like behaviors in this family. Kcnn3 expression in the amygdala correlated negatively with binge-like and voluntary ethanol drinking. C57BL/6J mice treated with chronic intermittent ethanol exposure and repeated swim stress consumed more ethanol in their home cages and showed hypophagia on the NSFT during prolonged abstinence. Pharmacologically targeting KCNN3 protein with the KCa2 channel positive modulator 1-EBIO decreased ethanol drinking and reduced latency to approach food during the NSFT in ethanol-dependent, stressed mice. Collectively these validation studies provide central nervous system mechanistic links into to the covariance of stress, anxiety, and AUD in the BXD strains. Further this analytical approach is effective in defining targets for treating alcohol dependence and comorbid mood and anxiety disorders.
Molecular Mechanism of Action of Mitochondrial Therapeutic SS-31 (Elamipretide): Membrane Interactions and Effects on Surface Electrostatics
Authors: Mitchell Wayne , Ng Emily A. , Tamucci Jeffrey D. , Boyd Kevin , Sathappa Murugappan , Coscia Adrian , Pan Meixia , Han Xianlin , Eddy Nicholas A. , May Eric R. , Szeto Hazel H. , Alder Nathan N.
Published: August 2019

Mitochondrial dysfunction includes heritable diseases, acquired pathologies, and age-related declines in health. Szeto-Schiller (SS) peptides comprise a class of amphipathic tetrapeptides that have demonstrated efficacy in treating a wide array of mitochondrial disorders, and are believed to target mitochondrial membranes due to their enrichment in the anionic phospholipid cardiolipin (CL). However, little is known regarding how SS peptides interact with or alter the physical properties of lipid bilayers. In this study, we have analyzed the interactions of the lead compound SS-31 (Elamipretide) with model and mitochondrial membranes using biophysical and computational approaches. Our results show that this polybasic peptide partitions into the membrane interfacial region with affinity and binding density that are directly related to surface charge. SS-31 binding does not destabilize lamellar bilayers even at the highest binding concentrations; however, it does cause saturable alterations in lipid packing. Most notably, SS-31 modulates the surface electrostatic properties of model and mitochondrial membranes, which could play a significant role in the mitoprotective properties of this compound. As a proof of concept, we show that SS-31 alters ion distribution at the membrane interface with implications for maintaining mitochondrial membranes subject to divalent cation (calcium) stress. Taken together, these results support a mechanism of action in which SS peptides interact with lipid bilayers and alter the biophysical (primarily electrostatic) properties of mitochondrial membranes as their primary mechanism of action. Understanding this molecular mechanism is key to the development of future compound variants with enhanced efficacy.

Significance

Szeto-Schiller (SS) peptides are among the most promising therapeutic compounds for mitochondrial dysfunction. However, the molecular target(s) and the mechanism of action of SS peptides are poorly understood. In this study, we evaluate the interaction of the lead compound SS-31 (Elamipretide) with mitochondrial and synthetic model membranes using a host of biophysical techniques. Our results show that SS-31 membrane interaction is driven largely by the negative surface charge of mitochondrial membranes and that SS-31 alters lipid bilayer properties, most notably electrostatics at the membrane interface. This work supports a mechanism in which SS peptides act on a key physical property of mitochondrial membranes rather than with a specific protein complex, consistent with the exceptionally broad therapeutic efficacy of these compounds.
The alkaliphilic side ofStaphylococcus aureus
Authors: Vaish Manisha , Jereen Amyeo , Ali Amall , Krulwich Terry Ann
Published: August 2019

The genome ofStaphylococcus aureushas eight structurally distinctcation/protonantiporters (CPA) that play significant roles in maintaining cytoplasmic pH and ions in extreme conditions. These antiporters enableS. aureusto persist under conditions that are favorable to the bacterium but unfavorable to animal host including humans. In this study, we report physiological roles and catalytic properties of NhaC (NhaC1, NhaC2 and NhaC3), CPA1 (CPA1-1 and CPA1-2) and CPA2 family antiporters and how these antiporters crosstalk with Mnh1, a CPA3 family antiporter, recently shown to play important roles in virulence and pH tolerance. Catalytic properties of antiporters were determined by Na+/H+and K+/H+antiport assays using everted membrane vesicles of a CPA-deficientE. coliKNabC host. NhaC and CPA1 candidates exhibited Na+/H+and K+/H+antiporter activity in the pH range between pH 7 to 9.5 but did not show significant role in halotolerance and osmotolerance alone. Interestingly, NhaC3 exhibited significant antiporter activity at alkaline pH and play major roles in pH and salt tolerance. CPA2 neither exhibited Na+or K+/H+exchange nor showed any active role in pH and salt tolerance. Double deletion ofmnhA1withnhaC1, nhaC3, cpa1-1 or cpa1-2respectively, madeS. aureusseverely sensitive at pH 7.5 under stress conditions indicating synergistic relationship of Mnh1 with these antiporters. The functional loss study of these antiporters inin-vivomouse infection model,nhaC3deletion showed significant loss ofS. aureusvirulence. Altogether, the current study indicates NhaC3 as a potential target againstS. aureusvirulence under extreme pH and salt conditions.

Importance

In this study, we established catalytic properties and physiological roles ofS. aureusNhaC, CPA1 and CPA2 family antiporters and their importance under salt and alkaline stress conditions. Except CPA2, all five antiporters of both families were active for Na+/H+and K+/H+exchange. CPA1-1 showed significant role in pH homeostasis at pH 7.5 whereas CPA1-2 and NhaCs were major contributors to halotolerance and osmotolerance at alkaline pH. The severity of growth deficit in double knockouts ofmnhA1with each ofnhaC1, nhaC2, nhaC3, cpa1-1orcpa1-2establishes their synergistic relationship in regulating pH and salt homeostasis. Deletion ofcpa1-1, cpa1-2andnhaC1, nhaC2, andnhaC3were assessed in mice model and NhaC3 was shown to play a major role inS. aureusvirulence.
Directed robust generation of functional retinal ganglion cells from Müller glia
Authors: Xiao Dongchang , Qiu Suo , Huang Xiuting , Zhang Rong , Lei Qiannan , Huang Wanjing , Chen Haiqiao , Gou Bin , Tie Xiaoxiu , Liu Sheng , Liu Yizhi , Jin Kangxin , Xiang Mengqing
Published: August 2019

Glaucoma and optic neuropathies cause progressive and irreversible degeneration of retinal ganglion cells (RGCs) and the optic nerve and are currently without any effective treatment. Previous research into cell replacement therapy of these neurodegenerative diseases has been stalled due to the limited capability for grafted RGCs to integrate into the retina and project properly along the long visual pathway to reach their brain targets. In vivo RGC regeneration would be a promising alternative approach but mammalian retinas lack regenerative capacity even though cold-blood vertebrates such as zebrafish have the full capacity to regenerate a damaged retina using Müller glia (MG) as retinal stem cells. Nevertheless, mammalian MG undergo limited neurogenesis when stimulated by retinal injury. Therefore, a fundamental question that remains to be answered is whether MG can be induced to efficiently regenerate functional RGCs for vision restoration in mammals. Here we show that without stimulating proliferation, the transcription factor (TF) Math5 together with a Brn3 TF family member are able to reprogram mature mouse MG into RGCs with exceedingly high efficiency while either alone has no or limited capacity. The reprogrammed RGCs extend long axons that make appropriate intra-retinal and extra-retinal projections through the entire visual pathway including the optic nerve, optic chiasm and optic tract to innervate both image-forming and non-image-forming brain targets. They exhibit typical neuronal electrophysiological properties and improve visual responses in two glaucoma mouse models:Brn3bnull mutant mice and mice with the optic nerve crushed (ONC). Together, our data provide evidence that mammalian MG can be reprogrammed by defined TFs to achieve robust in vivo regeneration of functional RGCs as well as a promising new therapeutic approach to restore vision to patients with glaucoma and other optic neuropathies.
A framework for design methods, models and techniques for product and process development
Authors: Sanhueza Karen Scarlette , Nikulin Christopher
Published: August 2019

Purpose

The purpose of this paper is to address the emerging need to map knowledge and information with a novel classification, suitable to have a clear and integrated overview of the design method, models and techniques from both the sides of product and process. The proposed classification allows to understand main relevance of different design methods, models and techniques according their characteristic and also level in where company usually applied.

Design/methodology/approach

The authors decided to structure the research into three steps: from the analysis of background literature, in order to draw the main evidences for the development of a novel classification, to their application. First, the papers search related to collect the different methods used in literature. Second, paper characterization which aims to understand main traits and usefulness of design methods, models and tools. Third, the assessment of design methods, models and tools according proposed classification.

Findings

Each method, model or technique would be more useful according to the context in which is applied. Most of methods and modes can be continuously improving, considering different sub-classification or complement each other, striving to compensate to the extent possible for weakness in any one of the approaches.

Research limitations/implications

The proposed classification did not deliver absolute results in every analyzed model or techniques, it delivered a wide range of possibilities in every sub-classification, thus the engineers get multiple options to choose depending on its main goal or the available resources.

Originality/value

The author’s proposal aims at filling a classification gap in the design method literature, which has to plausible in use. The different alternatives can be represented according to a scalable and hierarchical logic embedding also a more structured evaluation of the methods and tools in practice.
The impact of perceived justice on satisfaction and behavioral intentions in service encounters – a comparison and validation study
Authors: Carrillo Irma Magaña , Svensson Göran , Neira María del Carmen Otero
Published: August 2019

Purpose

The purpose of this paper is to test a research model based on the cause-and-effect relationships between perceived justice, service satisfaction and behavioral intention.

Design/methodology/approach

This paper is based on a questionnaire survey with service receivers in the Mexican telecom industry.

Findings

There are significant relationships between international/distributive justice and service satisfaction, as well as between service satisfaction and behavioral intention.

Research limitations/implications

The research model tested appears not to be context- and time-specific, but valid across contexts and through time.

Practical implications

The cause-and-effect relationships between perceived justice, service satisfaction and behavioral intention provide useful insights into service recovery strategies.

Originality/value

This paper provides additional empirical substantiations to existing theory and previous studies.
Brazilian apartheid: racism and segregation in Salvador, Brazil
Authors: Rotondano Ricardo Oliveira
Published: August 2019

Purpose

The purpose of this paper is to analyse empirically the racial relations of segregation of the black population in the city of Salvador, Brazil, which built according to a subtle model of the construction of differentiated spaces for the white population and the black population in the city.

Design/methodology/approach

The methodology used for the construction of this manuscript was that of the action research, through the insertion of the researcher within the field of study, obtaining observational perceptions of the inhabited place and collecting reports of the research subjects inserted in the field of study.

Findings

The present research obtained as final results the explicit characterisation of a veiled and subtle model of racial segregation imposed on the black population of the city of Salvador, manifesting the clear prejudice of the white population and also a state racism directed to the oppressed black population.

Originality/value

The originality of the research consists in the fact that there is no research modality within Brazil for the analysis of historical apartheid policies. The Brazilian state, in this sense, appears within the current framework of academic research as a clear incentive and propagator of governmental actions that corroborate the maintenance of the exclusionary city system, which separates the black and white population in differentiated social spaces.
Fame and fortune, or just fun? A study on why people create content on video platforms
Authors: Törhönen Maria , Sjöblom Max , Hassan Lobna , Hamari Juho
Published: August 2019

Purpose

The purpose of this paper is to examine the motivations behind online video content creation on services such as YouTube and Twitch. These activities, performed by private individuals online, have become increasingly monetized and professionalised through the accessible tools provided by video sharing services, which has presented a noteworthy manifestation of the increasing merger of the work and leisure within digital environments and the emergence of a hybrid form of work and play, playbour.

Design/methodology/approach

The data for the study were collected using an online survey of 377 video content creators and it was analysed via structural equation modelling.

Findings

The findings of the study indicate that although the practice of video content creation is becoming more commercialised and professionalised, the extrinsic motivations, often associated with work (e.g. income, prestige), remain less significant drivers for content creation than intrinsic motivations (e.g. enjoyment, socialisation), which are associated with leisure activities.

Originality/value

This study offers insight into how the authors have begun to reorganise the position in the new digital labour culture, where monotonous tasks are increasingly automated, allowing room for intrinsically driven playful labour to develop within the leisure activities.
Impacts of user interactions on trust development in C2C social commerce
Authors: Leung Wilson K.S. , Shi Si , Chow Wing S.
Published: August 2019

Purpose

The purpose of this paper is to understand the effect of two types of reciprocity (restricted reciprocity and generalized reciprocity) on customers’ trust in social commerce (s-commerce) and trust performance (purchase intention and word-of-mouth intention). Furthermore, this study examines how individual and contextual moderators (personal shopping experience and community shared language) could impact the trust development process.

Design/methodology/approach

This study adopted a survey method and obtained data from 287 users in a customer-to-customer (C2C) s-commerce platform. Structural equation modeling was used to examine the research hypotheses.

Findings

The results demonstrate that two types of reciprocity positively affect trust in s-commerce. Customers’ trust performance is significantly affected by trust in s-commerce. Additionally, shopping experience in s-commerce is found to positively moderate the relationship between restricted reciprocity and trust in s-commerce.

Research limitations/implications

The findings help to understand the nature and role of reciprocity in influencing trust and trust-related behaviors in the context of C2C s-commerce. The research also helps to explore the individual and contextual moderators that impact the effect of reciprocity on trust development.

Practical implications

The results offer a comprehensive view of trust building strategies for s-commerce practitioners, including shoppers, vendors and managers of s-commerce platforms.

Originality/value

This study is among the first few research studies that offers a theory-based conceptualization of reciprocity in C2C s-commerce and provides empirical support for the impact of reciprocity on customers’ trust in C2C s-commerce. In addition, this study devises a broader view of reciprocity based on restricted and generalized exchange principle to represent the interaction of vendor–shopper and shopper–shopper, respectively.
Global brands in sports: identifying low-risk business opportunities
Authors: Aguiar-Noury Alice , Garcia-del-Barrio Pedro
Published: August 2019

Purpose

The purpose of this paper is to accomplish several goals. First, it studies the relevance of the sports sector as part of the entertainment industry. Second, it identifies promising markets within the sports industry, paying special attention to the relative importance of soccer in the context of team-sport leagues. Finally, the paper helps entrepreneurs to recognized market opportunities in the sports industry by identifying the soccer clubs that were found to be low-risk global brands.

Design/methodology/approach

To evaluate the relevance of the entertainment and sports industries, both in the USA and EU-28, the authors rely on their respective contribution to the domestic product and to employment. Two procedures are proposed for establishing the status of global sport leagues: one is based on the annual revenues and the other on the degree of interest that the public shows for each professional sport league. (The latter is performed by comparing the intensity with which internet users search for contents related to each of the Top-10 sports leagues worldwide.) Finally, by estimating the fixed effects of a model in which sport performance is filtered out, we calculate the expected low-risk revenues that clubs generate due to their heterogeneous brand value.

Findings

This paper reaches some few relevant results. First, we find that the greater employment opportunities in the European sport industry are concentrated in the UK, Spain, France and Germany, which may orientate entrepreneurs to start projects in promising sport markets. Then, data on annual revenues is used to rank the main team-sport leagues worldwide: NFL, MLB, NBA, Premier League and NHL. Another rank is based on the degree of interest of fans (as captured by Google Trends) yields a different result, where the NFL, NBA and the UEFA Champions League are, respectively, at command. Besides, the paper also ranks clubs as valuable assets by identifying which of them are low-risk soccer brands. The empirical study provides insights to select business opportunities by targeting the less-risky clubs or leagues, by calculating the expected annual revenues of clubs regardless of their recent sports performances.

Originality/value

This paper is innovative in two ways. First, it develops an analysis based on Google Trends to establish the comparative status of team-sport leagues worldwide. Second, by adopting an original empirical approach, it identifies markets and brands to carry out low-risk entrepreneurial projects. The expected potential revenues derived from this procedure are not contingent to the risk due to poor sport achievements in a particular season. To our knowledge, researchers have not computed in the past such calculations as that we name here low-risk revenues.
Techniques for the identification of organizational knowledge management requirements
Authors: Giraldo Sobeida Margarita , Aguilar Luis Joyanes , Giraldo Lillyana María , Toro Iván Darío
Published: August 2019

Purpose

This paper aims to explore the requirements of organizational knowledge management initiatives using requirements engineering techniques, identifying the optimal techniques configuration and serving as a management tool for knowledge engineers.

Design/methodology/approach

The method is selection attributes. Knowledge management enablers are characterized and mapped with the coverage capabilities of requirements engineering techniques, using the attributes of the elicited object and a box-plot analysis. The information is gathered from 280 references, 32 companies and 16 experts in requirements engineering.

Findings

Requirements of organizational knowledge management initiatives are got optimally by combining interviews, use cases, scenarios, laddering and focus group techniques. The requirements of structure and processes are more complex to identify, while culture requirements are the best covered.

Research limitations/implications

Knowledge management enablers are analyzed according to the current studies and comprehension of engineering techniques.

Practical implications

Knowledge engineers need to consider the coverage capabilities of engineering techniques to design an optimal requirement identification and meet the objectives of organizational knowledge acquisition initiatives. Requirement engineers can improve the requirements identification by a staged selection process.

Social implications

The requirements of knowledge management initiatives that impact the community can be identified and traced to ensure the knowledge objectives. Requirements related to culture and people, like shared values, beliefs, and behaviors, are also considered.

Originality/value

To the best of the authors’ knowledge, this is the first study about formal requirement identification of knowledge management initiatives in the organizational context, providing the optimal configuration. A novel staged process is proposed for requirements engineering techniques selection, analyzing the enablers at component level and identifying the attributes associated with the elicited object.
Experimental and computational simulations for the effect of new Arylfuranylnicotinamidine derivatives against degradation of carbon steel in acid solutions
Authors: Fouda Abdelaziz S. , Ismail Mohamed A. , Abou-shahba Rabab M. , Hussein Walaa A. , El-habab Esraa S. , Abousalem Ashraf S.
Published: August 2019

Purpose

The purpose of this paper is to investigate three Arylfuranylnicotinamidine derivatives against corrosion of carbon steel (C-steel) in 1.0 M HCl by chemical and electrochemical means. The inhibition efficiency (%IE) increases with increasing the dose of inhibitors. The tested compounds exhibited improved performance at elevated temperature, with %IEreaching 93 percent at 21 µM. Tafel polarization method revealed that the tested compounds act as mixed-type inhibitors. The inhibition action was rationalized due to chemical adsorption of inhibition molecules on C-steel surface following Temkin’s isotherm. Surface examination was carried out by AFM and FTIR techniques. Further, theoretical chemical approaches were used to corroborate the experimental findings.

Design/methodology/approach

Experimental and computational methods were applied to investigate the efficiency of these new compounds. These studies are complemented with spectral studies and surface morphological scan by AFM. The theoretical results indicate good correlation with experimental findings.

Findings

The tested derivatives are promising corrosion inhibitors for C-steel in the acid environment. The molecular scaffold of this class of compounds can be used to design new highly efficient inhibitors by screening its activity by modeling studies.

Originality/value

The studied compounds are safe inhibitors and greatly adsorbed on Fe surface. The action of compounds is enhanced with temperature, which means these compounds can be used in higher temperature systems. The new compounds are effective at very low concentration.
Shifts in woody plant defence syndromes during leaf development
Authors: Barton Kasey E. , Edwards Kyle F. , Koricheva Julia
Published: August 2019

Herbivores target young leaves in forests world‐wide. How this strong and predictable selection pressure has shaped plant defence syndromes remains unclear. Specifically, whether young leaf herbivory has led to general global patterns of shifting leaf defences during leaf development (i.e. ontogenetic trajectories) remains unknown but likely.

Using meta‐analysis, we have synthesized developmental shifts in chemical, physical and indirect defence traits, as well as leaf nutrient content, during leaf expansion and maturation across 124 woody plant species. Leaf traits were compared for immature young leaves vs. mature leaves within studies, and these developmental shifts were then compared across studies to characterize general patterns.

Traits shifted strongly during leaf maturation, giving rise to discrete defence syndromes, with young leaves having significantly greater nutrient and secondary chemistry concentrations but reduced toughness and indirect defence traits than mature leaves. These patterns corroborate a growing consensus on the importance of ontogeny in plant defences, illustrating ontogenetic trajectories at the scale of leaves.

Trait developmental shifts were stronger in species with synchronous than asynchronous leaf flushing, but whether this reflects variation across biomes remains unclear.

Future research on under‐studied traits, such as alkaloids, cyanogenesis, leaf phosphorus content and indirect defence traits, and in a more biogeographic context will provide additional insights into the generality of shifts in defence syndromes during leaf development.

A free Plain Language Summary can be found within the Supporting Information of this article.
No energetic cost of tuberculosis infection in European badgers (Meles meles)
Authors: Barbour Katie , McClune David W. , Delahay Richard J. , Speakman John R. , McGowan Natasha E. , Kostka Berit , Montgomery W. Ian , Marks Nikki J. , Scantlebury David M.
Published: August 2019

Energy availability and energy use directly influence an organism's life history, fitness and ecological function. In wild animals, abiotic factors such as ambient temperature, season and rainfall, and biotic factors such as body mass, age, social group size and disease status, all potentially influence energy balance.

Relatively few studies have examined the effects of disease on the energy expenditure of wild animals. Such studies could further our understanding of factors influencing the transmission of zoonotic diseases. The European badger (Meles meles) is a medium‐sized carnivore that occurs in mixed‐sex, familial groups across much of its range. In the UK, they are a protected species but are also involved in the epidemiology of bovine tuberculosis (TB) in cattle.

We measured the daily energy expenditure (DEE) and resting metabolic rate (RMR) of wild badgers and related this to their TB infection status and a range of other interacting factors including season, group size, disease status, sex, age, body mass and body fat.

Individuals were larger and fatter when they were older, and fatter during the winter. Males were also heavier than females during the summer. In addition, individuals from smaller groups that were exposed to TB tended to have lower body mass.

There were no direct effects of disease status on DEE or RMR; however, there was a significant interaction whereby DEE increased with body mass in small groups but decreased with body mass in large groups.

Results are consistent with the costs of TB infection being met by compensatory mechanisms enabling badgers to survive for extended periods without exhibiting measurable energetic consequences.
FHA, Fannie Mae, Freddie Mac and the Great Recession
Authors: Passmore Wayne , Sherlund Shane M.
Published: August 2019

Did government mortgage programs mitigate the adverse economic effects of the 2007–2009 Great Recession? We find that counties with greater participation in precrisis government mortgage programs experienced less‐severe economic downturns during the Great Recession. In particular, counties with higher proportions of Federal Housing Administration (FHA), Fannie Mae and Freddie Mac lending prior to the financial crisis had smaller increases in serious delinquency and foreclosure rates; smaller declines in mortgage purchase originations, house prices, and new automobile purchases; and smaller increases in unemployment rates. Some of these effects were still evident in 2014 despite numerous new government policies and programs designed to promote economic recovery. We conclude that preexisting mortgage programs with more stable underwriting standards, credit risk pricing and liquidity played a key role in supporting economic conditions during the Great Recession.