bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling locust foraging: How and why food affects hopper band formation
Authors: Georgiou Fillipe , Buhl Jerome , Green J.E.F. , Lamichhane Bishnu , Thamwattana Natalie
Published: September 2020

Locust swarms are a major threat to agriculture, affecting every continent except Antarctica and impacting the lives of 1 in 10 people. Locusts are short horned grasshoppers that exhibit two behaviour types depending on their local population density. These are; solitarious, where they will actively avoid other locusts, and gregarious where they will seek them out. It is in this gregarious state that locusts can form massive and destructive flying swarms or plagues. However, these swarms are usually preceded by the formation of hopper bands by the juvenile wingless locust nymphs. It is thus important to understand the hopper band formation process to control locust outbreaks.

On longer time-scales, environmental conditions such as rain events synchronize locust lifecycles and can lead to repeated outbreaks. On shorter time-scales, changes in resource distributions at both small and large spatial scales have an effect on locust gregarisation. It is these short time-scale locust-resource relationships and their effect on hopper band formation that are of interest.

In this paper we investigate not only the effect of food on both the formation and characteristics of locust hopper bands but also a possible evolutionary explanation for gregarisation in this context. We do this by deriving a multi-population aggregation equation that includes non-local inter-individual interactions and local inter-individual and food interactions. By performing a series of numerical experiments we find that there exists an optimal food width for locust hopper band formation, and by looking at foraging efficiency within the model framework we uncover a possible evolutionary reason for gregarisation.

Author summary

Locusts are short horned grass hoppers that live in two diametrically opposed behavioural states. In the first, solitarious, they will actively avoid other locusts, whereas the second, gregarious, they will actively seek them out. It is in this gregarious state that locusts form the recognisable and destructive flying adult swarms. However, prior to swarm formation juvenile flightless locusts will form marching hopper bands and make their way from food source to food source. Predicting where these hopper bands might form is key to controlling locust outbreaks.

Research has shown that changes in food distributions can affect the transition from solitarious to gregarious. In this paper we construct a mathematical model of locust-locust and locust-food interactions to investigate how and why isolated food distributions affect hopper band formation. Our findings suggest that there is an optimal food width for hopper band formation and that being gregarious increases a locusts ability to forage when food width decreases.
Prevailing role of mucosal immunoglobulins and B cells in teleost skin immune responses to bacterial infection
Authors: Zhang Xiao-Ting , Yu Yong-Yao , Xu Hao-Yue , Huang Zhen-Yu , Liu Xia , Cao Jia-Feng , Meng Kai-Feng , Wu Zheng-Ben , Han Guang-Kun , Zhan Meng-Ting , Ding Li-Guo , Kong Wei-Guang , Li Nan , Takizawa Fumio , Oriol Sunyer J , Xu Zhen
Published: September 2020

The skin of vertebrates is the outermost organ of the body and serves as the first line of defense against external aggressions. In contrast to mammalian skin, that of teleost fish lacks keratinization and has evolved to operate as a mucosal surface containing a skin-associated lymphoid tissue (SALT). Thus far, IgT representing the prevalent immunoglobulin (Ig) in SALT have only been reported upon infection with a parasite. However, very little is known about the types of B cells and Igs responding to bacterial infection in the teleost skin mucosa, as well as the inductive or effector role of the SALT in such responses. To address these questions, here we analyzed the immune response of trout skin upon infection with one of the most widespread fish skin bacterial pathogens,Flavobacterium columnare. This pathogen induced strong skin innate immune and inflammatory responses at the initial phases of infection. More critically, we found that the skin mucus of fish having survived the infection contained significant IgT-but not IgM- or IgD-specific titers against the bacteria. Moreover, wedemonstrate the local proliferation and production of IgT+B-cells and specific IgT titers respectively within the SALT upon bacterial infection. Thus, our findings represent the first demonstration that IgT is the main Ig isotype induced by the skin mucosa upon bacterial infection, and that because of the large surface of the skin, its SALT probably represents a prominent IgT inductive site in fish.
CVB3 VP1 interacts with MAT1 to inhibit cell proliferation by interfering with Cdk-activating kinase complex activity in CVB3-induced acute pancreatitis
Authors: Zhang Hongxia , Zeng Lingbing , Liu Qiong , Jin Guilin , Zhang Jieyu , Li Zengbin , Xu Yilian , Huang Xiaotian
Published: September 2020

Coxsackievirus B3 (CVB3) belongs to the genusEnterovirusof the familyPicornaviridaeand can cause acute acinar pancreatitis in adults. However, the molecular mechanisms of pathogenesis underlying CVB3-induced acute pancreatitis have remained unclear. In this study, we discovered that CVB3 capsid protein VP1 inhibited pancreatic cell proliferation and exerted strong cytopathic effects on HPAC cells. Through yeast two-hybrid, co-immunoprecipitation, and confocal microscopy, we show that Menage a trois 1 (MAT1), a subunit of the Cdk-Activating Kinase (CAK) complex involved in cell proliferation and transcription, is a novel interaction protein with CVB3 VP1. Moreover, CVB3 VP1 inhibited MAT1 accumulation and localization, thus interfering with its interaction with CDK7. Furthermore, CVB3 VP1 could suppress CAK complex enzymic phosphorylation activity towards RNA Pol II and CDK4/6, direct substrates of CAK. VP1 also suppresses phosphorylation of retinoblastoma protein (pRb), an indirect CAK substrate, especially at phospho-pRb Ser780and phospho-pRb Ser807/811residues, which are associated with cell proliferation. Finally, we present evidence using deletion mutants that the C-terminal domain (VP1-D8, 768-859aa) is the minimal VP1 region required for its interaction with MAT1, and furthermore, VP1-D8 alone was sufficient to arrest cells in G1/S phase as observed during CVB3 infection. Taken together, we demonstrate that CVB3 VP1 can inhibit CAK complex assembly and activity through direct interaction with MAT1, to block MAT1-mediated CAK-CDK4/6-Rb signaling, and ultimately suppress cell proliferation in pancreatic cells. These findings substantially extend our basic understanding of CVB3-mediated pancreatitis, providing strong candidates for strategic therapeutic targeting.
Identification of microRNAs that stabilize p53 in HPV-positive cancer cells
Authors: Martínez-Noël Gustavo , Szajner Patricia , Kramer Rebecca E. , Boyland Kathleen A. , Sheikh Asma , Smith Jennifer A. , Howley Peter M.
Published: September 2020

Etiologically, 5% of all cancers worldwide are caused by the high-risk human papillomaviruses (hrHPVs). These viruses encode two oncoproteins (E6 and E7) whose expression is required for cancer initiation and maintenance. Among their cellular targets are the p53 and the retinoblastoma tumor suppressor proteins. Inhibition of the hrHPV E6-mediated ubiquitylation of p53 through the E6AP ubiquitin ligase results in the stabilization of p53, leading to cellular apoptosis. We utilized a live cell high throughput screen to determine whether exogenous microRNA (miRNA) transfection had the ability to stabilize p53 in hrHPV-positive cervical cancer cells expressing a p53-fluorescent protein as anin vivoreporter of p53 stability. Among the miRNAs whose transfection resulted in the greatest p53 stabilization was 375-3p that has previously been reported to stabilize p53 in HeLa cells, providing validation of the screen. The top 32 miRNAs in addition to 375-3p were further assessed using a second cell-based p53 stability reporter system as well as in non-reporter HeLa cells to examine their effects on endogenous p53 protein levels, resulting in the identification of 23 miRNAs whose transfection increased p53 levels in HeLa cells. While a few miRNAs that stabilized p53 led to decreases in E6AP protein levels, all targeted HPV oncoprotein expression. We further examined subsets of these miRNAs for their abilities to induce apoptosis and determined whether it was p53-mediated. The introduction of specific miRNAs revealed surprisingly heterogeneous responses in different cell lines. Nonetheless, some of the miRNAs described here have potential as therapeutics for treating HPV-positive cancers.

Importance

Human papillomaviruses cause approximately 5% of all cancers worldwide and encode genes that contribute to both the initiation and maintenance of these cancers. The viral oncoprotein E6 is expressed in all HPV-positive cancers and functions by targeting the degradation of p53 through the engagement of the cellular ubiquitin ligase E6AP. Inhibiting the degradation of p53 leads to apoptosis in HPV-positive cancer cells. Using a high throughput live cell assay we identified several miRNAs whose transfection stabilize p53 in HPV-positive cells. These miRNAs have the potential to be used in the treatment of HPV-positive cancers.
Opportunities and challenges for improving a Colombian public research program in plant breeding and plant genetic resources lead by Agrosavia
Authors: Galeano Carlos H. , Tehelen Katherine , Jiménez Hugo R. , González Carolina , Cerón-Souza Ivania
Published: September 2020

Agrosavia(Corporación Colombiana de Investigación Agropecuaria) is the Colombian state institution in charge of the agricultural research at the national level, including plant breeding. Since 2014, Agrosaviastarted to increase its research staff and has reset the leadership of public research to solve the needs of the agricultural sector population, focusing on small producers. However, the current team working on plant breeding and plant genetic resources are facing some challenges associated with generation gaps and the lack of a collaborative working plan for the next years. To identify the opportunities and actions in this research area, we surveyed all the 52 researchers working in Agrosaviain this area in 2017. We analyzed the opinions of researchers to detect the strengths and weaknesses of the program using a sentiment score. We also examined the networking to test both how consolidated the group is and if among top leaders are gender parity and also have a higher academic degree. Results showed that there is a mixed community of old and new researchers with clear gender bias in the proportion of male-female. Within the network, the interactions are weak, with several subgroups where the top-ten of both central leaders and the most influencer are frequently males with mostly an M.Sc. degree but with significant experience in the area. Researchers have an interest in 31 crops. From them, 26 are in the national germplasm bank, but this bank is not the primary source for their breeding programs. The top-five of plants with increasing interest are corn, cocoa tree, golden berries, oil palm, and sugarcane. Researchers also want to establish collaborations with 54 different institutions, where theUniversidad Nacional de Colombia, which is the top public university in the country, is on the head. Researchers also perceived weaknesses in the marker-assisted selection, experimental design, and participatory plant breeding, but those criticisms have a positive sentiment score average of 1.55 (0.3 SE) across 31 texts analyzed. Based on all results, we identified five critical strategic principles to improve the plant-breeding research program. They include a gender diversity policy to hire new researchers strategically to reduce the gender gap and strength the generational shift. Better collaboration between the national germplasm bank and plant breeding research. A coordinate plan where the studies focus on food security crops that the government supports independently of market trends. And finally, adequate spaces for the project’s design and training programs. Hence, we recommend the creation of a consultant group to implement these policies progressively in the next years.
Delayed maturation of the structural brain connectome in neonates with congenital heart disease
Authors: Feldmann Maria , Guo Ting , Miller Steven P. , Knirsch Walter , Kottke Raimund , Hagmann Cornelia , Latal Beatrice , Jakab Andras
Published: September 2020

There is emerging evidence for delayed brain development in neonates with congenital heart disease (CHD). We hypothesize that the perioperative development of the structural brain connectome is a proxy to such delays. Therefore, we set out to quantify the alterations and longitudinal pre- to postoperative changes in the connectome in CHD neonates and assess risk factors for disturbed perioperative network development relative to healthy term newborns. In this prospective cohort study, 114 term neonates with CHD underwent cardiac surgery at the University Children’s Hospital Zurich. Forty-six healthy term newborns were included as controls. Pre- and postoperative structural connectomes were derived from mean fractional anisotropy values of fibre pathways traced using diffusion tractography. Graph theory parameters calculated across a range of proportional cost thresholds were compared between groups by multi-threshold permutation correction adjusting for con-founders. Network based statistic was calculated for edgewise network comparison. White matter injury (WMI) volume was quantified on 3D T1-weighted images. Random coefficient mixed models with interaction terms of (i) CHD subtype and (ii) WMI volume with postmenstrual age at MRI respectively were built to assess modifying effects on network development. Pre- and postoperatively, at the global level, efficiency, indicative of network integration, was higher in controls compared to CHD neonates. In contrast, local efficiency and transitivity, indicative of network segregation, were higher in CHD neonates compared to controls (all p<0.025 for one-sided t-tests). Preoperatively these group differences were also found across multiple widespread nodes (all p<0.025, accounting for multiple comparison), whereas postoperatively nodal differences were not evident. At the edge-level, the majority of weaker connections in CHD neonates compared to controls involved interhemispheric connections (66.7% preoperatively; 54.5% postoperatively). A trend showing a more rapid pre- to postoperative decrease in local efficiency was found in class I CHD neonates compared to controls. In CHD neonates, larger WMI volume was associated with lower strength (p=0.0026) and global efficiency (p=0.0097). The maturation of the structural connectome is delayed in neonates with CHD, with a pattern of lower structural integration and higher segregation compared to healthy controls. Trend-level evidence indicated that normalized postoperative cardiac physiology in class I CHD neonates might improve structural network topology. In contrast, the degree of WMI burden negatively impacts network strength and integration. Further research is needed to elucidate how aberrant structural network development in CHD represents neural correlates of later neurodevelopmental impairments.
Cryo-EM structure of S-Trimer, a subunit vaccine candidate for COVID-19
Authors: Ma Jiahao , Su Danmei , Huang Xueqin , Liang Ying , Ma Yan , Liang Peng , Zheng Sanduo
Published: September 2020

Less than a year after its emergence, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected over 22 million people worldwide with a death toll approaching 1 million. Vaccination remains the best hope to ultimately put this pandemic to an end. Here, using Trimer-Tag technology, we produced both wild-type (WT) and furin site mutant (MT) S-Trimers for COVID-19 vaccine studies. Cryo-EM structures of the WT and MT S-Trimers, determined at 3.2 Å and 2.6 Å respectively, revealed that both antigens adopt a tightly closed conformation and their structures are essentially identical to that of the previously solved full-length WT S protein in detergent. These results validate Trimer-Tag as a platform technology in production of metastable WT S-Trimer as a candidate for COVID-19 subunit vaccine.
Microplastic fibers affect dynamics and intensity of CO2and N2O fluxes from soil differently
Authors: Rillig Matthias C. , Hoffmann Mathias , Lehmann Anika , Liang Yun , Lück Matthias , Augustin Jürgen
Published: September 2020

Microplastics may affect soil ecosystem functioning in critical ways, with previously documented effects including changes in soil structure and water dynamics; this suggests that microbial populations and the processes they mediate could also be affected. Given the importance for global carbon and nitrogen cycle and greenhouse warming potential, we here experimentally examined potential effects of plastic microfiber additions on CO2and N2O greenhouse gas fluxes. We carried out a fully factorial laboratory experiment with the factors presence of microplastic fibers (0.4% w/w) and addition of urea fertilizer (100 mg N kg−1). The conditions in an intensively N-fertilized arable soil were simulated by adding biogas digestate at the beginning of the incubation to all samples. We continuously monitored CO2and N2O emissions from soil before and after urea application using a custom-built flow-through steady-state system, and we assessed soil properties, including soil structure. Microplastics affected soil properties, notably increasing soil aggregate water-stability and pneumatic conductivity, and caused changes in the dynamics and overall level of emission of both gases, but in opposite directions: overall fluxes of CO2were increased by microplastic presence, whereas N2O emission were decreased, a pattern that was intensified following urea addition. This divergent response is explained by effects of microplastic on soil structure, with the increased air permeability likely improving O2supply: this will have stimulated CO2production, since mineralization benefits from better aeration. Increased O2would at the same time have inhibited denitrification, a process contributing to N2O emissions, thus likely explaining the decrease in the latter. Our results clearly suggest that microplastic consequences for greenhouse gas emissions should become an integral part of future impact assessments, and that to understand such responses, soil structure should be assessed.
A common binding motif in the ET domain of BRD3 forms polymorphic structural interfaces with host and viral proteins
Authors: Aiyer Sriram , Swapna G.V.T. , Ma Li-Chung , Liu Gaohua , Hao Jingzhou , Chalmers Gordon , Jacobs Brian C. , Montelione Gaetano T. , Roth Monica J.
Published: September 2020

The extra-terminal (ET) domain of BRD3 is conserved among BET proteins (BRD2, BRD3, BRD4), interacting with multiple host and viral protein-protein networks. Solution NMR structures of complexes formed between BRD3-ET domain with either the 79-residue murine leukemia virus integrase (IN) C-terminal domain (IN329-408), or its 22-residue IN tail peptide (TP) (IN386-407) alone, reveal similar intermolecular three-stranded β-sheet formation.15N relaxation studies reveal a 10-residue linker region (IN379-388) tethering the SH3 domain (IN329-378) to the ET-binding motif (IN389-405)-ET complex. This linker has restricted flexibility, impacting its potential range of orientations in the IN - nucleosome complex. The complex of the ET-binding peptide of host NSD3 protein (NSD3148-184) and BRD3-ET domain includes a similar three-stranded β-sheet interaction, but the orientation of the β−hairpin is flipped compared to the two IN : ET complexes. These studies expand our understanding of molecular recognition polymorphism in complexes of ET-binding motifs with viral and host proteins.

Highlights

The BRD3 ET domain binds to key peptide motifs of diverse host and viral proteins.

These complexes reveal conformational plasticity in molecular recognition.

NMR studies demonstrate restricted interdomain motion in the IN CTD / ET complex.

A cost-effective approach is described for producing isotopically-labeled peptides.

Etoc Blurb

We address structurally how the MLV Integrase (IN) usurps the host function of the BET protein through comparative studies of the IN : Brd3 ET complex with that of the host NSD3. MLV integration and thus its pathogenesis is driven through protein interactions of the IN : BET family.
Identifying candidateCulicoidesspp. (Diptera: Ceratopogonidae) for the study of interactions withCandidatusCardinium hertigii (Bacteroidetes)
Authors: Pilgrim Jack , Siozios Stefanos , Baylis Matthew , Venter Gert , Garros Claire , Hurst Gregory D. D.
Published: September 2020

Culicoidesbiting midges (Diptera: Ceratopogonidae) are disease vectors responsible for the transmission of several viruses of economic and animal health importance. The recent deployment ofWolbachiawith pathogen-blocking capacity to control viral disease transmission by mosquitoes has led to a focus on the potential use of endosymbionts to control arboviruses transmitted by other vector species. Previous screens ofCulicoideshave described the presence ofCandidatusCardinium hertigii (Bacteroidetes). However, the biological impact of this symbiont is yet to be uncovered and awaits a suitable system to studyCardinium-midge interactions. To identify candidate species to investigate these interactions, accurate knowledge of the distribution of the symbiont withinCulicoidespopulations is needed. We used a sensitive nested PCR assay to screenCardiniuminfection in 337 individuals of 25Culicoidesspecies from both Palearctic and Afrotropical regions. Infections were observed in several vector species includingC. imicolaand the pulicaris complex (C. pulicaris, C. bysta, C. newsteadiandC. punctatus) with prevalence ranging from low and intermediate, to fixation. Infection inC. pulicariswas very rare in comparison to a previous study, and there is evidence the prior record of high prevalence represents a laboratory contamination error. Phylogenetic analysis based on the Gyrase B gene sequence grouped all new isolates within “group C” of the genus, a clade which has to date been exclusively described inCulicoides. Through a comparison of our results with previous screens, we evaluate the suitability ofCardinium-infected species for future work pertaining to the symbiont.
An Interpreted Atlas of Biosynthetic Gene Clusters from 1000 Fungal Genomes
Authors: Robey Matthew T. , Caesar Lindsay K. , Drott Milton T. , Keller Nancy P. , Kelleher Neil L.
Published: September 2020

Fungi are prolific producers of natural products, compounds which have had a large societal impact as pharmaceuticals, mycotoxins, and agrochemicals. Despite the availability of over 1000 fungal genomes and several decades of compound discovery efforts from fungi, the biosynthetic gene clusters (BGCs) encoded by these genomes and the associated chemical space have yet to be analyzed systematically. Here we provide detailed annotation and analyses of fungal biosynthetic and chemical space to enable genome mining and discovery of fungal natural products. Using 1037 genomes from species across the fungal kingdom (e.g., Ascomycota, Basidiomycota, and non-Dikarya taxa), 36,399 predicted BGCs were organized into a network of 12,067 gene cluster families (GCFs). Anchoring these GCFs with reference BGCs enabled automated annotation of 2,026 BGCs with predicted metabolite scaffolds. We performed parallel analyses of the chemical repertoire of Fungi, organizing 15,213 fungal compounds into 2,945 molecular families (MFs). The taxonomic landscape of fungal GCFs is largely species-specific, though select families such as the equisetin GCF are present across vast phylogenetic distances with parallel diversifications in the GCF and MF. We compare these fungal datasets with a set of 5,453 bacterial genomes and their BGCs and 9,382 bacterial compounds, revealing dramatic differences between bacterial and fungal biosynthetic logic and chemical space. These genomics and cheminformatics analyses reveal the large extent to which fungal and bacterial sources represent distinct compound reservoirs. With a >10-fold increase in the number of interpreted strains and annotated BGCs, this work better regularizes the biosynthetic potential of fungi for rational compound discovery.

Significance Statement

Fungi represent an underexploited resource for new compounds with applications in the pharmaceutical and agriscience industries. Despite the availability of >1000 fungal genomes, our knowledge of the biosynthetic space encoded by these genomes is limited and ad hoc. We present results from systematically organizing the biosynthetic content of 1037 fungal genomes, providing a resource for data-driven genome mining and large-scale comparison of the genetic and molecular repertoires produced in fungi and compare to those present in bacteria.
Experiences of receiving and providing maternity care during the COVID-19 Pandemic in Australia: a five-cohort cross-sectional comparison
Authors: Bradfield Zoe , Wynter Karen , Hauck Yvonne , Vasilevski Vidanka , Kuliukas Lesley , Wilson Alyce N , Szabo Rebecca A , Homer Caroline SE , Sweet Linda
Published: September 2020

Introduction

The global COVID-19 pandemic has radically changed the way health care is delivered in many countries around the world. Evidence on the experience of those receiving or providing maternity care is important to guide practice through this challenging time.

Methods

A cross-sectional study was conducted in Australia. Five key stakeholder cohorts were included to explore and compare the experiences of those receiving or providing care during the COVID-19 pandemic. Women, their partners, midwives, medical practitioners and midwifery students who had received or provided maternity care from March 2020 onwards in Australia were invited to participate in an online survey. which was released between 13th May and 24th June 2020; a total of 3701 completed responses were received.

Findings

While anxiety related to COVID-19 was high among all five cohorts, there were statistically significant differences between the responses from each cohort for most survey items. Women were more likely to indicate concern about their own and family’s health and safety in relation to COVID-19 whereas midwives, doctors and midwifery students were more likely to be concerned about occupational exposure to COVID-19 through working in a health setting than those receiving care through attending these environments. Midwifery students and women’s partners were more likely to respond that they felt isolated because of the changes to the way care was provided. Despite concerns about care received or provided not meeting expectations, most respondents were satisfied with the quality of care provided, although midwives and midwifery students were less likely to agree.

Conclusion

This paper provides a unique exploration and comparison of experiences of receiving and providing maternity care during the COVID-19 pandemic in Australia. Findings are useful to support further service changes and future service redesign. New evidence provided offers unique insight into key stakeholders’ experiences of the rapid changes to health services.
Two new polymorphic forms of combretastatin A-4, an antitumour agent
Authors: Grześkiewicz Anita M. , Stefański Tomasz , Dutkiewicz Zbigniew , Buśko Daria , Kubicki Maciej
Published: September 2020

Two new polymorphic forms of combretastatin A-4 {systematic name: 2-methoxy-5-[(E)-2-(3,4,5-trimethoxyphenyl)ethenyl]phenol, C18H20O5, CA-4}, an inhibitor of tubulin polymerization at the colchicine binding site, were identified. A number of crystallization attempts led to the orthorhombic form, with two molecules in the asymmetric part of the unit cell; obtaining a different form required the experiment to be moved to another laboratory. None of the attempts resulted in the monoclinic form described earlier. The three different forms contain molecules of significantly different geometries, which can be related to conformational freedom, postulated as the result of biological studies. In addition, the packing modes in all three forms are basically different. The structural differences at both the molecular and the supramolecular level have also been studied via calculations of energies and a topological analysis of the electron density. The results confirm the role of weak interactions in the determination of crystal architecture and additionally hint at an explanation for the results of crystallization attempts: the new monoclinic form has significantly lower energy than the form reported earlier.
Crystal structure of {N
1,N
3-bis[(1-benzyl-1H-1,2,3-triazol-4-yl)methylidene]-2,2-dimethylpropane-1,3-diamine}bis(thiocyanato-κN)iron(II)
Authors: Znovjyak Kateryna , Seredyuk Maksym , Malinkin Sergey O. , Shova Sergiu , Soliev Lutfullo
Published: September 2020

The unit cell of the title compound, [FeII(NCS)2(C25H28N8)], consists of two charge-neutral complex molecules related by an inversion centre. In the complex molecule, the tetradentate ligand N
1,N
3-bis[(1-benzyl-1H-1,2,3-triazol-4-yl)methylene]-2,2-dimethylpropane-1,3-diamine coordinates to the FeII ion through the N atoms of the 1,2,3-triazole moieties and aldimine groups. Two thiocyanate anions, coordinating through their N atoms, complete the coordination sphere of the central ion. In the crystal, neighbouring molecules are linked through weak C—H...π, C—H...S and C—H...N interactions into a two-dimensional network extending parallel to (011). The intermolecular contacts were quantified using Hirshfeld surface analysis and two-dimensional fingerprint plots, revealing the relative contributions of the contacts to the crystal packing to be H...H (35.2%), H...C/C...H (26.4%), H...S/S...H (19.3%) and H...N/N...H (13.9%).
Structural barriers to scientific progress
Authors: Cowtan K.
Published: September 2020

Structural biases, which are intrinsic in the social structures in which we function, play a key role in maintaining boundaries between traditionally privileged and underprivileged groups; however, they are particularly difficult to identify from within those societies. Two instances are highlighted in which the social structures of science appear to have discouraged collaboration, to the disadvantage of software and data users. Possible links are suggested to the strongly hierarchical structure of science and other factors which may in turn also serve to maintain sex and/or gender disparities in participation in the scientific endeavour.
A closer look at stochastic frontier analysis in economics
Authors: Nguyen Hung T.
Published: September 2020

Purpose

While there exist many surveys on the use stochastic frontier analysis (SFA), many important issues and techniques in SFA were not well elaborated in the previous surveys, namely, regular models, copula modeling, nonparametric estimation by Grenander’s method of sieves, empirical likelihood and causality issues in SFA using regression discontinuity design (RDD) (sharp and fuzzy RDD). The purpose of this paper is to encourage more research in these directions.

Design/methodology/approach

A literature survey.

Findings

While there are many useful applications of SFA to econometrics, there are also many important open problems.

Originality/value

This is the first survey of SFA in econometrics that emphasizes important issues and techniques such as copulas.
Pocket parks for promoting social interaction among residents of Baghdad City
Authors: Salih Sarah Abdulkareem , Ismail Sumarni , Mseer Aysha
Published: September 2020

Purpose

The residents of Baghdad city has been suffering from various issues, including poor social relations, low quality of life, as well as neglect of many public spaces and small parks. Therefore, there is a need to devise effective alternatives to compensate for the loss of large public open spaces so as to enhance the residents’ social interactions and other social activities. Having that said, this study identified the types and characteristics of public open spaces to enhance residents’ social activities in Baghdad city.

Design/methodology/approach

This study adopted the questionnaire survey method to gather quantitative data from 306 respondents based on the single-stage random procedure. The targeted population of this study refers to the residents of the Karkh district, the western part of Baghdad.

Findings

The study outcomes highlight the need to provide pocket parks with adequate characteristics to promote the residents’ social interactions in Baghdad city.

Practical implications

This study contributes by emphasizing the significance of establishing pocket parks for social interaction in Baghdad City.

Originality/value

The study shows a number of solutions related to pocket parks by studying the critical actionable attributes that can be embedded into new development, land-use policies, or to upgrade existing parks. The study may serve as a useful reference for urban and landscape planners, architects, social psychologists, the Municipal of Baghdad, and other interested researchers in this field.
Expectations and everyday opportunities for building trust in the food system
Authors: Tonkin Emma , Henderson Julie , Meyer Samantha B. , Coveney John , Ward Paul R. , McCullum Dean , Webb Trevor , Wilson Annabelle M.
Published: September 2020

Purpose

Consumers’ trust in food systems is essential to their functioning and to consumers’ well-being. However, the literature exploring how food safety incidents impact consumer trust is theoretically underdeveloped. This study explores the relationship between consumers’ expectations of the food system and its actors (regulators, food industry and the media) and how these influence trust-related judgements that consumers make during a food safety incident.

Design/methodology/approach

In this study, two groups of purposefully sampled Australian participants (n = 15) spent one day engaged in qualitative public deliberation to discuss unfolding food incident scenarios. Group discussion was audio recorded and transcribed for the analysis. Facilitated group discussion included participants' expected behaviour in response to the scenario and their perceptions of actors' actions described within the scenario, particularly their trust responses (an increase, decrease or no change in their trust in the food system) and justification for these.

Findings

The findings of the study indicated that food incident features and unique consumer characteristics, particularly their expectations of the food system, interacted to form each participant's individual trust response to the scenario. Consumer expectations were delineated into “fundamental” and “anticipatory” expectations. Whether fundamental and anticipatory expectations were in alignment was central to the trust response. Experiences with the food system and its actors during business as usual contributed to forming anticipatory expectations.

Originality/value

To ensure that food incidents do not undermine consumer trust in food systems, food system actors must not only demonstrate competent management of the incident but also prioritise trustworthiness during business as usual to ensure that anticipatory expectations held by consumers are positive.
Introducing a strategic perspective in lean thinking applications through system dynamics modelling: the dynamic Value Stream Map
Authors: Noto Guido , Cosenz Federico
Published: September 2020

Purpose

Lean Thinking is an operation management discipline which aims to identify, map and analyse the activities forming a process to detect “value waste” and outline the most effective flow of activities to execute in sequence. Process mapping is often developed in lean projects through the use of the Value Stream Map (VSM). Like many other management tools, the VSM adopts a static and non-systemic perspective in the representation of an organizational process. This may result in the implementation of Lean projects inconsistent with the overall organizational long-term strategy, thus leading to dysfunctional performance. In order to overcome this limit, the paper suggests combining VSM with System Dynamics (SD) modelling.

Design/methodology/approach

The paper is based on a review of the literature on VSM. This review is matched with an analysis of SD modelling principles aimed at explaining the practical and theoretical contribution of this approach to operation and strategic management practices. An illustrative case study is then provided to explore the practical implications of the proposed approach.

Findings

Our results show that SD modelling provides robust methodological support to VSM and Lean Thinking due to its inner characteristics, namely: simulation, systemic view, explicit link between system structure and behaviour and effective visual representation.

Originality/value

This research proposes a novel approach to design VSMs aimed at fostering a strategic perspective in Lean Thinking applications. Such an approach connects two fields of research and practice – i.e. VSM and SD modelling – which have traditionally been kept separated or, at least, partially combined for specific organizational sub-systems, thereby neglecting a broader strategic view of the entire process system.
Commercial hard drive failures in a data center application and the role of SMART attribute information
Authors: Pecht Michael , Elburn Edmond
Published: September 2020

Purpose

The reliability of hard disk drives (HDDs) is dependent on the drive construction, as well as the operational and environmental conditions, in which the drive is used. Self-monitoring, analysis and reporting technology (SMART) continuously provides attribute information on HDD usage and degradation characteristics.

Design/methodology/approach

This paper aims to analyze the reported failures Backblaze data set for ST3000DM001 HDDs intended for desktop applications within a data center application. SMART attributes used for predicting failure are discussed and analyzed over the life of many hard drives. A case study on the actual use of SMART and the limitations of the SMART attribute information, the data center’s information and the use of desktop drives in a commercial application are also presented.

Findings

The analysis showed that when Backblaze started to record the data, the hard disk drives had already worked for a while with power on hours mean and standard deviation of 6,683 and 365 h, respectively. Therefore, it is possible that some SMART attributes have experienced critical values that have not been recorded by Backblaze. Additionally, 8% of all ST3000DM001 drives that Backblaze labeled as failed did not have raw values above zero for the five attributes that were considered critical. Backblaze recorded 25 SMART attributes in total for all hard disk drive brands where ST3000DM001 having 83.3% of the attributes ranked as the drive with the most attributes recorded. Having more recorded attributes with critical values leads to label more ST3000DM001 drives as failed while there might be the hard drives from the other brands or part numbers that experienced more critical SMART attributes but were not labeled as failed because of the lack of records.

Originality/value

It is an original work carried out at the Center for Advanced Life Cycle Engineering, University of Maryland.
Seeking sustainable futures in marketing and consumer research
Authors: Davies Iain , Oates Caroline J. , Tynan Caroline , Carrigan Marylyn , Casey Katherine , Heath Teresa , Henninger Claudia E. , Lichrou Maria , McDonagh Pierre , McDonald Seonaidh , McKechnie Sally , McLeay Fraser , O'Malley Lisa , Wells Victoria
Published: September 2020

Purpose

Seeking ways towards a sustainable future is the most dominant socio-political challenge of our time. Marketing should have a crucial role to play in leading research and impact in sustainability, yet it is limited by relying on cognitive behavioural theories rooted in the 1970s, which have proved to have little bearing on actual behaviour. This paper aims to interrogate why marketing is failing to address the challenge of sustainability and identify alternative approaches.

Design/methodology/approach

The constraint in theoretical development contextualises the problem, followed by a focus on four key themes to promote theory development: developing sustainable people; models of alternative consumption; building towards sustainable marketplaces; and theoretical domains for the future. These themes were developed and refined during the 2018 Academy of Marketing workshop on seeking sustainable futures. MacInnis’s (2011) framework for conceptual contributions in marketing provides the narrative thread and structure.

Findings

The current state of play is explicated, combining the four themes and MacInnis’s framework to identify the failures and gaps in extant approaches to the field.

Research limitations/implications

This paper sets a new research agenda for the marketing discipline in quest for sustainable futures in marketing and consumer research.

Practical implications

Approaches are proposed which will allow the transformation of the dominant socio-economic systems towards a model capable of promoting a sustainable future.

Originality/value

The paper provides thought leadership in marketing and sustainability as befits the special issue, by moving beyond the description of the problem to making a conceptual contribution and setting a research agenda for the future.
Gaining insights into why professionals continue or abandon pro bono service
Authors: Patterson Paul G. , McColl-Kennedy Janet R. , Lee Jenny (Jiyeon) , Brady Michael K.
Published: September 2020

Purpose

The purpose of this study is to empirically examine the personal/situational and business factors that encourage or discourage pro bono service of professionals based on the theory of institutional logics framework and the extended purchase behavior model.

Design/methodology/approach

This paper collected the data using a mixed-method approach: 30 qualitative interviews and 443 cross-sectional surveys from professional service providers across industries. The constructs of interest were measured with the scales compiled from the literature, industry reports and the preliminary interviews.

Findings

The results highlight emotional value derived from personal/situational factors (intrinsic motivation, personal recognition, philanthropic disposition and lack of appreciation) drove professionals’ intentions to continue to undertake pro bono work. While employer encouragement motivated professionals to engage in pro bono service, the prospect of gaining business opportunities and time constraints discouraged this important practice.

Research limitations/implications

While there has been considerable empirical study undertaken on charitable behavior, little attention has been given to this form of giving (pro bono work by service professionals). Overall, the results show that personal satisfaction with and feeling good about the study undertaken are required for continuation. Professionals who are intrinsically motivated, philanthropic-natured and properly-acknowledged through positive feedback and recognition tend to experience positive feelings that engender their good intentions to help the underprivileged, those in need and society more generally. The findings thus complement and extend the academic and industry literature on charitable giving.

Practical implications

This research identifies the drivers of service professionals’ continuation of pro bono work that the third sector relies heavily on its sustainability. As the study findings suggesting the importance of personal recognition, nonprofit organizations should demonstrate genuine gratitude and recognition of these professionals so that they continue to give their services pro bono.

Originality/value

The research is the first empirical study to develop a conceptual model that delineates the drivers and/or barriers to professionals continuing pro bono service. Unlike the previous study lacking a theoretical basis, this paper proposed and tested the conceptual model derived from the institutional logics framework and the extended purchase behavior model.
Review on state-of-the-art dynamic task allocation strategies for multiple-robot systems
Authors: N. Seenu , R.M. Kuppan Chetty , M.M. Ramya , Janardhanan Mukund Nilakantan
Published: September 2020

Purpose

This paper aims to present a concise review on the variant state-of-the-art dynamic task allocation strategies. It presents a thorough discussion about the existing dynamic task allocation strategies mainly with respect to the problem application, constraints, objective functions and uncertainty handling methods.

Design/methodology/approach

This paper briefs the introduction of multi-robot dynamic task allocation problem and discloses the challenges that exist in real-world dynamic task allocation problems. Numerous task allocation strategies are discussed in this paper, and it establishes the characteristics features between them in a qualitative manner. This paper also exhibits the existing research gaps and conducive future research directions in dynamic task allocation for multiple mobile robot systems.

Findings

This paper concerns the objective functions, robustness, task allocation time, completion time, and task reallocation feature for performance analysis of different task allocation strategies. It prescribes suitable real-world applications for variant task allocation strategies and identifies the challenges to be resolved in multi-robot task allocation strategies.

Originality/value

This paper provides a comprehensive review of dynamic task allocation strategies and incites the salient research directions to the researchers in multi-robot dynamic task allocation problems. This paper aims to summarize the latest approaches in the application of exploration problems.
Why organizations fail to share knowledge: an empirical investigation and opportunities for improvement
Authors: Israilidis John , Siachou Evangelia , Kelly Stephen
Published: September 2020

Purpose

This paper explores critical failure factors (CFFs) in the context of knowledge sharing. It provides further insights into what can cause knowledge- sharing failures, inflexible knowledge-sharing strategies and ineffective knowledge- sharing mechanisms. It also examines how practitioners can reduce or even mitigate such dysfunctions.

Design/methodology/approach

A case-based inductive approach was conducted. Data were collected from two studies applying mixed methods. The first data set included nine in-depth, semi-structured interviews with highly skilled personnel from an aerospace and defense organization. The second data source included 375 successfully completed questionnaires from participants employed at the same organization.

Findings

The paper identifies six CFFs with an impact on knowledge sharing. It also reveals that managing organizational ignorance can play a key role in generating new knowledge and averting failure. Study findings provide insights into the importance of identifying these failures when sharing knowledge and propose relevant mitigation strategies.

Originality/value

This paper identifies a range of empirically validated CFFs that complement the extant work on the complexity of knowledge sharing and have hitherto not been seen in the literature. It also provides a more nuanced understanding of why both organizations and their people often fail to share knowledge by exploring the role of organizational ignorance.