bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling infection dynamics and mitigation strategies to support K-6 in-person instruction during the COVID-19 pandemic
Authors: Morrison Douglas E. , Nianogo Roch , Manuel Vladimir , Arah Onyebuchi A. , Anderson Nathaniel , Kuo Tony , Inkelas Moira
Published: March 2021

Objective

To support safer in-person K-6 instruction during the coronavirus disease 2019 (COVID- 19) pandemic by providing public health authorities and school districts with a practical model of transmission dynamics and mitigation strategies.

Methods

We developed an agent-based model of infection dynamics and preventive mitigation strategies such as distancing, health behaviors, surveillance and symptomatic testing, daily symptom and exposure screening, quarantine policies, and vaccination. The model parameters can be updated as the science evolves and are adjustable via an online user interface, enabling users to explore the effects of interventions on outcomes of interest to states and localities, under a variety of plausible epidemiological and policy assumptions.

Results

Under default assumptions, secondary infection rates and school attendance are substantially affected by surveillance testing protocols, vaccination rates, class sizes, and effectiveness of safety education.

Conclusions

Our model helps policymakers consider how mitigation options and the dynamics of school infection risks affect outcomes of interest. The model’s parameters can be immediately updated in response to changes in epidemiological conditions, science of COVID-19 transmission dynamics, testing and vaccination resources, and reliability of mitigation strategies.
COVID-19 Vaccination Priority Evaluation
Authors: Dujmović Jozo , Tomasevich Daniel
Published: March 2021

Computing the COVID-19 vaccination priority is an urgent and ubiquitous decision problem. In this paper we propose a solution of this problem using the LSP evaluation method. Our goal is to develop a justifiable and explainable quantitative criterion for computing a vaccination priority degree for each individual in a population. Performing vaccination in the order of the decreasing vaccination priority produces maximum positive medical, social, and ethical effects for the whole population. The presented method can be expanded and refined using additional medical and social conditions. In addition, the same methodology is suitable for solving other similar medical priority decision problems, such as priorities for organ transplants.
Household COVID-19 risk and in-person schooling
Authors: Lessler Justin , Grabowski M. Kate , Grantz Kyra H. , Badillo-Goicoechea Elena , Metcalf C. Jessica E. , Lupton-Smith Carly , Azman Andrew S. , Stuart Elizabeth A.
Published: March 2021

In-person schooling has proved contentious and difficult to study throughout the SARS-CoV-2 pandemic. Data from a massive online survey in the United States indicates an increased risk of COVID-19-related outcomes among respondents living with a child attending school in-person. School-based mitigation measures are associated with significant reductions in risk, particularly daily symptoms screens, teacher masking, and closure of extra-curricular activities. With seven or more mitigation measures, the association between in-person schooling and COVID-19-related outcomes all but disappears. Teachers working outside the home were more likely to report COVID-19-related outcomes, but this association is similar to other occupations (e.g., healthcare, office work). In-person schooling is associated with household COVID-19 risk, but this risk can likely be controlled with properly implemented school-based mitigation measures.

One sentence summary

Living with children attending in-person school is linked to a higher risk of COVID-19 outcomes, which school-based interventions can mitigate.
Increased region of surround stimulation enhances contextual feedback and feedforward processing in human V1
Authors: Revina Yulia , Petro Lucy S. , Denk-Florea Cristina B. , Rao Isa S. , Muckli Lars
Published: March 2021

The majority of synaptic inputs to the primary visual cortex (V1) are non-feedforward, instead originating from local and anatomical feedback connections. Animal electrophysiology experiments show that feedback signals originating from higher visual areas with larger receptive fields modulate the surround receptive fields of V1 neurons. Theories of cortical processing propose various roles for feedback and feedforward processing, but systematically investigating their independent contributions to cortical processing is challenging because feedback and feedforward processes coexist even in single neurons. Capitalising on the larger receptive fields of higher visual areas compared to primary visual cortex (V1), we used an occlusion paradigm that isolates top-down influences from feedforward processing. We utilised functional magnetic resonance imaging (fMRI) and multi-voxel pattern analysis methods in humans viewing natural scene images. We parametrically measured how the availability of contextual information determines the presence of detectable feedback information in non-stimulated V1, and how feedback information interacts with feedforward processing. We show that increasing the visibility of the contextual surround increases scene-specific feedback information, and that this contextual feedback enhances feedforward information. Our findings are in line with theories that cortical feedback signals transmit internal models of predicted inputs.

Significance Statement

The visual system has circuit mechanisms for processing scene context. These circuits involve lateral and feedback inputs to neurons. These inputs interact with feedforward inputs and modulate neuronal responses to visual stimuli presented outside their receptive fields. Systematically investigating independent contributions of feedback and feedforward processes is challenging because they coexist even in single neurons. Here we use an occlusion paradigm to isolate feedback and lateral signals in human participants viewing natural scene images in fMRI. We show that increasing the visibility of the contextual surround increases scene-specific feedback information, which also enhances feedforward signals. Our findings are in line with theories that cortical feedback signals carry abstract internal models that combine with more detailed representations in primary visual cortex.
Mice immunized with the vaccine candidate HexaPro spike produce neutralizing antibodies against SARS-CoV-2
Authors: Seephetdee Chotiwat , Buasri Nattawut , Bhukhai Kanit , Srisanga Kitima , Manopwisedjaroen Suwimon , Lertjintanakit Sarat , Phueakphud Nut , Pakiranay Chatbenja , Kangwanrangsan Niwat , Srichatrapimuk Sirawat , Sungkanuparph Somnuek , Kirdlarp Suppachok , Chutipongtanate Somchai , Thitithanyanont Arunee , Hongeng Suradej , Wongtrakoongate Patompon
Published: March 2021

Updated and revised versions of COVID-19 vaccines are vital due to genetic variations of the SARS-CoV-2 spike antigen. Furthermore, vaccines that are safe, cost-effective, and logistically friendly are critically needed for global equity, especially for middle to low income countries. Recombinant protein-based subunit vaccines against SARS-CoV-2 have been reported with the use of the receptor binding domain (RBD) and the prefusion spike trimers (S-2P). Recently, a new version of prefusion spike trimers, so called “HexaPro”, has been shown for its physical property to possess two RBD in the “up” conformation, as opposed to just one exposed RBD found in S-2P. Importantly, this HexaPro spike antigen is more stable than S-2P, raising its feasibility for global logistics and supply chain. Here, we report that the spike protein HexaPro offers a promising candidate for SARS-CoV-2 vaccine. Mice immunized by the recombinant HexaPro adjuvanted with aluminium hydroxide using a prime-boost regimen produced high-titer neutralizing antibodies for up to 56 days after initial immunization against live SARS-CoV-2 infection. In addition, the level of neutralization activity is comparable to that of convalescence sera. Our results indicate that the HexaPro subunit vaccine confers neutralization activity in sera collected from mice receiving the prime-boost regimen.
Beyond colour gamuts: Novel metrics for the reproduction of photoreceptor signals
Authors: Hexley Allie C. , Morimoto Takuma , Smithson Hannah E. , Spitschan Manuel
Published: March 2021

Colour gamuts describe the chromaticity reproduction capabilities of a display, i.e. its ability to reproduce the relative cone excitations from real-world radiance spectra. While the cones dominate “canonical” visual function (i.e. perception of colour, space, and motion) under photopic light levels, they are not the only photoreceptors in the human retina. Rods and melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs) also respond to light and contribute to both visual and non-visual light responses, including circadian rhythms, sleep-wake control, mood, pupil size, and alertness. Three-primary display technologies, with their focus on reproducing colour, are not designed to reproduce the rod and melanopsin excitations. Moreover, conventional display metrics used to characterize three-primary displays fail to describe the display’s ability (or inability) to reproduce rod and melanopsin excitations, and thus do not capture the display’s ability to reproduce the full human physiological response to light. In this paper, three novel physiologically relevant metrics are proposed for quantifying the reproduction and distortion of the photoreceptor signals by visual displays. A novel equal-luminance photoreceptor excitation diagram is proposed, extending the well-known MacLeod-Boynton chromaticity diagram, to allow visualizations of the five-dimensional photoreceptor signal space in a three-dimensional projection.
A BCI-based vibrotactile neurofeedback training improves motor cortical excitability during motor imagery
Authors: Grigorev N. , Savosenkov A. , Lukoyanov M. , Udoratina A. , Shusharina N. , Kaplan A. , Hramov A. , Kazantsev V. , Gordleeva S.
Published: March 2021

In this study, we address the issue of whether vibrotactile feedback can enhance the motor cortex excitability translated into the plastic changes in local cortical areas during motor imagery (MI) BCI-based training. For this purpose, we focused on two of the most notable neurophysiological effects of MI – the event-related-desynchronization (ERD) level and the increase in cortical excitability assessed with navigated transcranial magnetic stimulation (nTMS). For TMS navigation, we used individual high-resolution 3D brain MRIs. Ten BCI-naive and healthy adults participated in this study. The MI (rest or left/right hand imagery using Graz-BCI paradigm) tasks were performed separately in the presence and absence of feedback. To investigate how much the presence/absence of vibrotactile feedback in MI BCI-based training could contribute to the sensorimotor cortical activations, we compared the MEPs amplitude during MI after training with and without feedback. In addition, the ERD levels during MI BCI-based training were investigated. Our findings provide evidence that applying vibrotactile feedback during MI training leads to (i) an enhancement of the desynchronization level of mu-rhythm EEG patterns over the contralateral motor cortex area corresponding to the MI of the non-dominant hand; (ii) an increase in motor cortical excitability in hand muscle representation corresponding to a muscle engaged by the MI.
Synergistic positive feedback underlying seizure initiation
Authors: Graham Robert T. , Parrish R. Ryley , Alberio Laura , Johnson Emily L. , Owens Laura J. , Trevelyan Andrew J.
Published: March 2021

Seizure onset is a critically important brain state transition that has proved very difficult to predict accurately from recordings of brain activity. Here we show that an intermittent, optogenetic, stimulation paradigm reveals a latent change in dendritic excitability that is tightly correlated to the onset of seizure activity. Our data show how the precipitous nature of the transition can be understood in terms of multiple, synergistic positive feedback mechanisms: raised intracellular Cl-and extracellular K+, coupled to a reduced threshold for dendritic plateau potentials, and which in turn leads to a switch to pyramidal burst firing. Notably, the stimulation paradigm also delays the evolving epileptic activity, meaning that not only can one monitor seizure risk safely, it may even have an additional anti-epileptic benefit.

One Sentence Summary

Rapid transitions into seizures arise from mutually accelerating feedback loops, involving changes in dendritic excitability
VPRBP functions downstream of the androgen receptor and OGT to restrict p53 activation in prostate cancer
Authors: Poulose Ninu , Forsythe Nicholas , Polonski Adam , Gregg Gemma , Maguire Sarah , Fuchs Marc , Minner Sarah , Sauter Guido , McDade Simon S. , Mills Ian G.
Published: March 2021

A comprehensive understanding of androgen receptor (AR) signalling mechanisms during prostate carcinogenesis is instrumental in developing novel therapies. Studies have shown glycosylation as a key androgen regulated process and that O-GlcNAc transferase (OGT), the enzyme that catalyses the covalent addition of UDP-N-acetylglucosamine (UDP-GlcNAc) to serine and threonine residues of proteins, is often up-regulated in prostate cancer (PCa) with its expression correlated with high Gleason score. In this study we have identified an AR and OGT co-regulated factor, VPRBP also known as DCAF1. We show that VPRBP is regulated by the AR at the transcript level, and stabilized by OGT at the protein level. VPRBP knockdown in PCa cells led to a significant decrease in cell proliferation, p53 stabilization, nucleolar fragmentation and increased p53 recruitment to the chromatin. In human prostate tumor samples, VPRBP protein overexpression correlated with AR amplification, OGT overexpression, early biochemical relapse and poor clinical outcome. Analysis of TCGA datasets found a positive correlation of VPRBP with AR mRNA expression. Furthermore, AR activity gene signature analysis revealed a positive correlation of VPRBP with a subset of AR target genes implying that VPRBP has a preferential regulatory impact on part of the AR regulome. In conclusion, we have shown that VPRBP/DCAF1 promotes PCa cell proliferation by restraining p53 activation under the influence of the AR and OGT as well as uncovered a unique subset of AR activity gene signature that correlates with VPRBP expression with the potential for new avenues for patient stratification and treatment.
The component parts of bacteriophage virions accurately defined by a machine-learning approach built on evolutionary features
Authors: Thung Tze Y. , White Murray E. , Dai Wei , Wilksch Jonathan J. , Bamert Rebecca S. , Rocker Andrea , Stubenrauch Christopher J , Williams Daniel , Huang Cheng , Schittelhelm Ralf , Barr Jeremy J. , Jameson Eleanor , McGowan Sheena , Zhang Yanju , Wang Jiawei , Dunstan Rhys A. , Lithgow Trevor
Published: March 2021

Antimicrobial resistance (AMR) continues to evolve as a major threat to human health and new strategies are required for the treatment of AMR infections. Bacteriophages (phages) that kill bacterial pathogens are being identified for use in phage therapies, with the intention to apply these bactericidal viruses directly into the infection sites in bespoke phage cocktails. Despite the great unsampled phage diversity for this purpose, an issue hampering the roll out of phage therapy is the poor quality annotation of many of the phage genomes, particularly for those from infrequently sampled environmental sources. We developed a computational tool called STEP3to use the “evolutionary features” that can be recognized in genome sequences of diverse phages. These features, when integrated into an ensemble framework, achieved a stable and robust prediction performance when benchmarked against other prediction tools using phages from diverse sources. Validation of the prediction accuracy of STEP3was conducted with high-resolution mass spectrometry analysis of two novel phages, isolated from a watercourse in the Southern Hemisphere. STEP3provides a robust computational approach to distinguish specific and universal features in phages to improve the quality of phage cocktails, and is available for use athttp://step3.erc.monash.edu/.

IMPORTANCE

In response to the global problem of antimicrobial resistance there are moves to use bacteriophages (phages) as therapeutic agents. Selecting which phages will be effective therapeutics relies on interpreting features contributing to shelf-life and applicability to diagnosed infections. However, the protein components of the phage virions that dictate these properties vary so much in sequence that best estimates suggest failure to recognize up to 90% of them. We have utilised this diversity in evolutionary features as an advantage, to apply machine learning for prediction accuracy for diverse components in phage virions. We benchmark this new tool showing the accurate recognition and evaluation of phage components parts using genome sequence data of phages from under-sampled environments, where the richest diversity of phage still lies.
Selective attention and decision-making have separable neural bases in space and time
Authors: Moerel Denise , Rich Anina N. , Woolgar Alexandra
Published: March 2021

Attention and decision-making processes are fundamental to cognition. However, they are usually experimentally confounded, making it difficult to link neural observations to specific processes. Here we separated the effects of selective attention from the effects of decision-making on human brain activity, using a two-stage task where the attended stimulus and decision were orthogonal and separated in time. Multivariate pattern analyses of multimodal neuroimaging data revealed the dynamics of perceptual and decision-related information coding through time (magnetoencephalography (MEG)), space (functional Magnetic Resonance Imaging (fMRI)), and their combination (MEG-fMRI fusion). Our MEG results showed an effect of attention before decision-making could begin, and fMRI results showed an attention effect in early visual and frontoparietal regions. Model-based MEG-fMRI fusion suggested that attention boosted stimulus information in frontoparietal and early visual regions before decision-making was possible. Together, our results suggest that attention affects neural stimulus representations in frontoparietal regions independent of decision-making.
Episodic memory in aspects of brain information transfer by resting-state network topology
Authors: Yan Tianyi , Wang Gongshu , Wang Li , Liu Tiantian , Li Ting , Wang Luyao , Suo Dingjie , Funahashi Shintaro , Chen Duanduan , Wang Bin , Wu Jinglong
Published: March 2021

Studies suggest that resting-state functional connectivity conveys cognitive information; also, activity flow mediates cognitive information transfer. However, the exact mechanism of interregional interactions underlying episodic memory remains unclear. We performed a combined analysis of task-evoked activity and resting-state functional connectivity by activity flow mapping to estimate the information transfer mechanism of episodic memory. We found that the cognitive control and attentional networks were the most recruited structures in information transfers during both encoding and retrieval processes; these networks were correlated with task-evoked activation. Differences in information transfer intensity between encoding and retrieval mainly existed in the visual, somatomotor and hippocampal systems. Furthermore, information transfer showed high predictive power for episodic memory ability and mediated relationships between task-evoked activation and memory performance. Additional analysis indicated that structural connectivity had a transportive role in information transfer. Finally, our study presented the information transfer mechanism of episodic memory from multiple neural perspectives.
Visual Cortical Area MT is Required for Development of the Dorsal Stream and Associated Visuomotor Behaviours
Authors: Kwan William C. , Chang Chia-Kang , Yu Hsin-Hao , Mundinano Inaki C. , Fox Dylan M. , Homman-Ludiye Jihane , Bourne James A.
Published: March 2021

The middle temporal (MT) area of the extrastriate visual cortex has long been studied in adulthood for its distinctive physiological properties and function as a part of the dorsal stream, yet interestingly possesses a similar maturation profile as the primary visual cortex (V1). Here we examined whether an early-life lesion of MT altered the dorsal stream development and the behavioural precision of reaching to grasp sequences. We observed permanent changes in the anatomy of cortices associated with both reaching (PE and MIP) and grasping (AIP), as well as in reaching and grasping behaviours. In addition, we observed a significant impact on the anatomy of V1 and the direction sensitivity of V1 neurons in the lesion projection zone. These findings indicate that area MT is a crucial node for the development of the primate vision, impacting both V1 and areas in the dorsal visual pathway known to mediate visually guided manual behaviours.

Teaser

The early life loss of visual area MT leads to significant anatomical, physiological and behavioural changes.
Human iPSC-derived renal cells change their immunogenic properties during maturation: Implications for regenerative therapies
Authors: Rossbach Bella , Hariharan Krithika , Mah Nancy , Oh Su-Jun , Volk Hans-Dieter , Reinke Petra , Kurtz Andreas
Published: March 2021

Therapeutic success of human induced pluripotent stem cell (hiPSC)-based therapies critically depends on immunological compatibility of the hiPSC-derived transplant. As grafted hiPSC-derived cells are often immature, we hypothesized that their immunologic properties may change due to post-grafting maturation. Subsequently, this will affect their interaction with the host immune system and may compromise graft tolerance. In the present study allogeneic and autologous cellular immunity of primary cells, therof reprogrammed hiPSC, hiPSC-derived progenitor and terminally differentiated cells was investigatedin vitroby using renal cells as a model system. In contrast to allogeneic primary cells, hiPSC-derived early renal progenitors and mature renal epithelial cells were both tolerated not only by autologous but also by allogeneic T cells. These immune-privileged properties resulted from active immune-modulation and low immune visibility, which declined during the process of cell maturation. However, autologous and allogeneic natural killer (NK) cell responses were not suppressed by hiPSC-derived renal cells and efficiently changed NK cell activation status. These findings clearly show a dynamic stage-specific dependency of autologous and allogeneic T- and NK cell responses to the hiPSC-derived renal cell lineage with consequences for effective cell therapies. The study suggests that hiPSC-derived early progenitors may provide advantageous immune suppressive properties when applied in cell therapy. The data furthermore indicate a need to suppress NK cell activation in allogeneic as well as autologous settings.
The establishment of variant surface glycoprotein monoallelic expression revealed by single-cell RNA-seq ofTrypanosoma bruceiin the tsetse fly salivary glands
Authors: Hutchinson Sebastian , Foulon Sophie , Crouzols Aline , Menafra Roberta , Rotureau Brice , Griffiths Andrew D. , Bastin Philippe
Published: March 2021

The long and complexTrypanosoma bruceidevelopment in the tsetse fly vector culminates when parasites gain mammalian infectivity in the salivary glands. A key step in this process is the establishment of monoallelic variant surface glycoprotein (VSG) expression and the formation of the VSG coat. The establishment of VSG monoallelic expression is complex and poorly understood, due to the multiple parasite stages present in the salivary glands. Therefore, we sought to further our understanding of this phenomenon by performing single-cell RNA-sequencing (scRNA-seq) on these trypanosome populations. We were able to capture the developmental program of trypanosomes in the salivary glands, identifying populations of epimastigote, gamete, pre-metacyclic and metacyclic cells. Our results show that parasite metabolism is dramatically remodeled during development in the salivary glands, with a shift in transcript abundance from tricarboxylic acid metabolism to glycolytic metabolism. Analysis ofVSGgene expression in pre-metacyclic and metacyclic cells revealed a dynamicVSGgene activation program. Strikingly, we found that pre-metacyclic cells contain transcripts from multipleVSGgenes, which resolves to singularVSGgene expression in mature metacyclic cells. Single molecule RNA fluorescencein situhybridisation (smRNA-FISH) ofVSGgene expression followingin vitrometacyclogenesis confirmed this finding. Our data demonstrate that multipleVSGgenes are transcribed before a single gene is chosen. We propose a transcriptional race model governs the initiation of monoallelic expression.
Playing soft with cooperators emerges as a moral norm and promotes cooperation in evolutionary games
Authors: Salahshour Mohammad
Published: March 2021

In many biological populations, individuals face a complex strategic setting, where they need to make strategic decisions over a diverse set of issues. To study evolution in such a complex strategic context, here we introduce evolutionary models where individuals play two games with different structures. Individuals decide upon their strategy in a second game based on their knowledge of their opponent’s strategy in the first game. By considering a case where the first game is a social dilemma, we show that, as long as the second game has an asymmetric Nash equilibrium, the system possesses a spontaneous symmetry-breaking phase transition above which the symmetry between cooperation and defection breaks. A set of cooperation supporting moral norms emerges according to which cooperation stands out as a valuable trait. Notably, the moral system also brings a more efficient allocation of resources in the second game. This observation suggests a moral system has two different roles: Promotion of cooperation, which is against individuals’ self-interest but beneficial for the population, and promotion of organization and order, which is at both the population’s and the individual’s self-interest. Interestingly, the latter acts like a Trojan horse: Once established out of individuals’ self-interest, it brings the former with itself. Furthermore, we show that in structured populations, recognition noise can have a surprisingly positive effect on the evolution of moral norms and facilitates cooperation in the Snow Drift game.
Managerial overconfidence and internal control weaknesses: evidence from Iranian firms
Authors: Safari Gerayli Mehdi , Abdoli Mohammadreza , Valiyan Hasan , Damavandi Ali
Published: March 2021

Purpose

The characteristic of managers’ personality is a key factor in their decision-making. One of the most important personality characteristic of managers is overconfidence. Overconfident managers have false trust about their abilities and have a positive view of the firm’s future performance. Thus, the purpose of this study is to investigate the association between managerial overconfidence and internal control weaknesses (ICW) of the firms listed on the Tehran Stock Exchange (TSE).

Design/methodology/approach

Sample includes the 480 firm-year observations from companies listed on the TSE during the years 2013–2017, and the hypothesis is tested using multivariate regression model based on panel data analysis.

Findings

The authors found that managerial overconfidence increases the firms’ ICW. The findings are robust to alternative measure of managerial overconfidence, individual analysis of the research hypothesis for each year and endogeneity concern. Moreover, additional analysis reveals that the positive relationship between managerial overconfidence and ICW is less pronounced in larger firms.

Originality/value

To the best of the authors’ knowledge, this is the first study to analyze the association between managerial overconfidence and ICW in emerging capital markets and, therefore, can contribute to extend the current literature on managerial overconfidence and ICW in developing countries, especially Iran’s emerging capital market.
Global integration of the Gulf cooperation council markets
Authors: Zhao Xiaobing
Published: March 2021

Purpose

This paper investigates the global financial integration of the Gulf Cooperation Council markets, which is important for financial economists, global investors and policymakers.

Design/methodology/approach

The first step is to estimate a benchmark one-factor model and multifactor models over the entire sample period to obtain the time-invariant global integration estimates for the Gulf Cooperation Council markets. Because the global integration of the Gulf Cooperation Council markets may be time varying, the second step is to use 24-month rolling regressions to estimate the time-varying integration estimates. To explicitly test for structural breaks in global integration, this study applies a supremum Wald test to endogenously search for structural breaks.

Findings

Empirically, consistent evidence suggests that the Gulf Cooperation Council markets are increasingly integrated with international equity markets at different levels of financial development and from different regions. However, compared to other emerging and frontier markets, the global integration of the Gulf Cooperation Council markets is still relatively low, suggesting that these markets still offer significant diversification benefits for global investors.

Originality/value

This study contributes to the literature by systematically investigating the global integration of the Gulf Cooperation Council markets with monthly data (to account for the gradual information diffusion in international equity markets) and a longer sample period (to more robustly identify the trend in the global integration).
A novel cooperative model in the collection of infectious waste in COVID-19 pandemic
Authors: Valizadeh Jaber , Mozafari Peyman
Published: March 2021

Purpose

Production of waste has been increased exponentially due to world industrialization and urban and machine life expansion. On the other hand, the outbreak of the COVID-19 coronavirus quickly became a global crisis. This crisis has added a large amount of waste to urban waste. The purpose of this study is to create cooperation between municipal waste collector contractors.

Design/methodology/approach

Thus, a mathematical model is proposed under uncertain conditions, which includes the volume of municipal waste and infectious waste including personal protective equipment and used equipment for patients. To reduce total costs, the results are evaluated with four cooperative game theory methods such as Shapley value, t value, core center and least core. Ultimately, the saved cost by cooperation in each coalition is allocated fairly among the contractors. Finally, a comparison was made between the solution methods based on the value of the objective function and the solution time.

Findings

The results indicate that the proposed cooperative method increases cost savings and reduces the fine of residual waste. Therefore, it can be mentioned that this kind of cooperation would finally result in more incentives for contractors to form larger coalitions. Genetic algorithms were used to solve the large-scale model.

Originality/value

The proposed model boosts the current understanding of waste management in the COVID-19 pandemic. The paper adds additional value by unveiling some key future research directions. This guidance may demonstrate possible existing and unexplored gaps so that researchers can direct future research to develop new processes.
Hybrid fuzzy MCDM and FMEA integrating with linear programming approach for the health and safety executive risks: a case study
Authors: Khalilzadeh Mohammad , Ghasemi Peiman , Afrasiabi Ahmadreza , Shakeri Hedieh
Published: March 2021

Purpose

The purpose of this study is to present a new failure mode and effects analysis (FMEA) approach based on fuzzy multi-criteria decision-making (MCDM) methods and multi-objective programming model for risk assessment in the planning phase of the oil and gas construction projects (OGCP) in Iran.

Design/methodology/approach

This research contains multiple steps. First, 19 major potential health and safety executive (HSE) risks in OGCP were classified into six categories with the Delphi method. These factors were distinguished by the review of project documentation, checklist analysis and consulting with experts. Then, using the fuzzy SWARA method, the authors calculated the weights of major HSE risks. Subsequently, FMEA and PROMETHEE approaches were used to identify the priority of main risk factors. Eventually, a binary multi-objective linear programming approach was developed to select the risk response strategies, and an augmented e-constraint method (AECM) was used.

Findings

Regarding the project triple well-known constraints of time, cost and quality, which organizations usually confront, the HSE risks of OGCP were identified and prioritized. Also, the appropriate risk response strategies were also suggested to the managers to be adopted regarding the situations.

Originality/value

The present research points at the HSE risks’ assessment integrating the fuzzy FMEA, step-wise weight assessment ratio analysis and PROMETHEE techniques with the AECM. Further to the authors’ knowledge, the quantitative assessment of the HSE risks of OGCP has not been done using the combination of the fuzzy FMEA, MCDM and AECMs.
Pursuing premium: comparing pre-owned versus new durable markets
Authors: Miller Chadwick J. , Brannon Daniel C.
Published: March 2021

Purpose

The purpose of this paper is to investigate whether consumers in pre-owned durable goods markets (such as pre-owned automobiles) purchase products with higher premium/luxury positioning in a vertical line-up compared to consumers in new durable goods markets. The moderating role of brand loyalty on choice is also investigated.

Design/methodology/approach

The hypotheses are tested using a data set that includes the sales of new and pre-owned vehicles from an independently owned automotive dealer in the Northwestern USA during the first nine months of 2017 (N = 200). An ordered logit regression is used to estimate the relationship between consumers’ purchase of pre-owned vs new vehicles and the premium-level of the model that they choose, while controlling for the vehicle price. Two experimental robustness tests are conducted to provide empirical evidence of the proposed theoretical process.

Findings

Consumers who purchased pre-owned vehicles chose models with higher premium/luxury positioning compared to consumers who purchased new vehicles, even when controlling for price. This effect was moderated by brand loyalty, such that consumers’ premium-level of purchase was magnified if they previously owned a vehicle of the same brand. The results of an experimental robustness test indicated that consumers’ preference for pre-owned vehicles with higher premium/luxury positioning was because of greater perceptions of the quality along the dimensions of versatility, performance and prestige.

Practical implications

Sellers of complex durable goods (e.g. automobiles) should consider segmenting their upselling strategies for pre-owned vs new products. They should specifically focus more effort on the upselling of pre-owned durables as buyers appear more likely to pursue premium/luxury alternatives compared to new durables. Further, they should focus upselling efforts for pre-owned durables on brand loyal consumers.

Originality/value

To the best of the authors’ knowledge, this work is the first to examine consumers’ desire for pre-owned durable goods with premium/luxury positioning in a vertical product line-up. Further, it is also the first to explore the role of brand loyalty in shaping consumer preferences for premium/luxury pre-owned durable goods. As such, it makes an important contribution to an emerging literature exploring the appeal of premium and luxury pre-owned goods. Much work in this area has focused on the motivations that consumers have for buying pre-owned premium and luxury nondurable goods, such as vintage clothing or accessories. By contrast, the present research investigates the appeal of premium/luxury positioning for complex, pre-owned durable goods (vehicles), which are more difficult for consumers to evaluate at the point-of-purchase.
Bioremediation of cardboard recycling industry effluents using mixed fungal culture
Authors: Hosseini Zeinab , Ghaneian Mohammad Taghi , Ghafourzade Mahin , Jafari Nodoushan Abbasali
Published: March 2021

Purpose

This paper aims to evaluate the bioremediation [chemical oxygen demand (COD) and color removal] of the effluent from the cardboard recycling industry in Yazd, central province of Iran, using mixed fungal culture.

Design/methodology/approach

First, the effluent samples from the cardboard recycling industry were cultured on potato dextrose agar medium to isolate native fungal colonies. The grown colonies were then identified using morphological macroscopic and microscopic characteristics to choose the dominant fungi for bioremediations. The mixed cultures of Aspergillus niger, Aspergillus flavus and Penicillium digitatum were finally used for bioremediation experiments of the cardboard recycling industry. A suspension containing 1 × 106 CFU/ml of fungal spores was prepared from each fungus, separately and their homogenous mixture. Sewage samples were prepared and sterilized and used at 25%, 50% and 90% dilutions and pH levels of 5, 7 and 8 for bioremediation tests using mixed fungal spores. Following that, 10 ml of the mixed fungal spores were inoculated into the samples for decolorization and COD removal and incubated for 10 days at 30°C. The amount of COD removal and decolorization were measured before incubation and after 3, 6 and 10 days of inoculation. In this research, the color was measured by American Dye Manufacturer Institute and COD by the closed reflux method. The results of the present study were analyzed using SPSS 21 statistical software and one-way ANOVA tests at p-value < 0.05.

Findings

The results of this research showed that the mean decolorization by mixed fungal culture over 10 days at pH levels of 5, 7 and 8 were 44.40%, 45.00% and 36.84%, respectively, and the mean COD removal efficiency was 71.59%, 73.54% and 16.55%, respectively. Moreover, the mean decolorization at dilutions of 25%, 50% and 90% were 45.00%, 31.93% and 30.53%, respectively, and the mean COD removal efficiency was 73.54%, 62.38% and 34.93%, respectively. Therefore, the maximal COD removal and decolorization efficiency was obtained at dilution of 25% and pH 7.

Originality/value

Given that limited studies have been conducted on bioremediation of the effluent from the cardboard recycling industry using fungal species, this research could provide useful information on the physicochemical properties of the effluent in this industry.
The canned food drive: What do students learn?
Authors: White Elizabeth S.
Published: March 2021

Purpose

Numerous studies have shown that community service during adolescence is associated with positive youth outcomes and future civic engagement (Reinders and Youniss, 2006; Yates and Youniss, 1996). However, less is known about the ways in which students participate in and perceive intermittent, noncurricular community service. The purpose of this study is to examine seventh and eighth grade students' (N = 22) experiences during a common school-wide community service event: the canned food drive.

Design/methodology/approach

Data include students' journal responses to questions about the food drive including their feelings about the event, learning that took place, positive parts of the drive and challenges. An inductive qualitative analysis was used.

Findings

Analysis of students' responses revealed that most students perceived themselves and their classmates as being very helpful to the community and described feeling happiness and pride from the event, even when participation was minimal or nonexistent. While some students reported awareness of poverty and inequality after the food drive, many of their comments about those receiving the donations included deficit-oriented terminology and cognitive distancing by positioning those experiencing food insecurity as “the other” and different from themselves.

Practical implications

Findings highlight the benefits and shortcomings of community service, as class biases and surface-level ideas about helping may be unintentionally reinforced. Recommendations to address these issues are discussed.

Originality/value

Given the prevalence of community service in schools, qualitative research is needed to understand firsthand how students experience these events.
A Green's function approach to the study of effective anisotropic properties of the Barnett Shale
Authors: Ghosh Avradip , Morshed Sharif
Published: March 2021

The purpose of this paper is to derive the Green's function of an anisotropic elastic medium and validate it with the effective stiffness tensor of Barnett Shale. We have derived the frequency‐dependent Green's function by using the spectral theorem for matrices, thus simplifying the process of computing Green's function and obtaining analytical solutions. Evaluating the inverse of the Green–Christoffel tensor is an essential part of computing the Green's function. Based on the degeneracy of the eigenvalues of the Green–Christoffel tensor, the inverse of the Green–Christoffel tensor is expressed in the form of partial fractions. Consequently, the stiffness tensors from the measurement of core samples of Barnett Shale are used to validate the Green's function. We use the generalized singular approximation method of effective medium theory to model the effective stiffness of the core samples from microstructural properties. The generalized singular approximation method also allows us to compute the theoretical stiffness tensor of the Barnett Shale for porosity variations. The behaviour of the Green's function, which reflects the behaviour of the media, is studied in the static, low‐ and high‐frequency domains and under different physical parameters. It is observed that the variations of crack‐induced porosity produce different trends in Green's function for vertically transverse isotropic and horizontally transverse isotropic media. Thus, the variation of porosity is observed to be influential in differentiating between transverse isotropic media that have inclusions. The Green's function results presented in this paper have direct applications in the construction of synthetic seismograms for unbounded transversely isotropic media.
Reproductive biology of the South American cycad Zamia boliviana, involving brood‐site pollination
Authors: Segalla Rosane , Pinheiro Fábio , Morellato Leonor Patrícia Cerdeira
Published: March 2021

Brood‐site pollination mutualisms represent extreme levels of reciprocal specialization between plants and insects. Several studies have revealed intimate associations between cycads and their insect pollinators across different continents. However, the reproductive biology of South American cycads is still poorly understood, with limited empirical data available. Here, we investigated the plant–pollinator interactions of Zamia boliviana (Cycadales, Zamiaceae), which is distributed on savanna patches in Brazil and Bolivia. Our aim was to examine reproductive biology (strobili development and their visitors) to identify potential pollinators from the perspective of dioecy and expectations of obligatory mutualism. We monitored reproductive cohorts and registered the strobiliʼs visitors. We classified the visitorsʼ activities and described the behavior of the most active and recurring ones in both reproductive structures to ascertain the potential pollinators and their relationship with the Z. boliviana. In situ experiments were used to demonstrate efficacy in seed production. Although other insects visit the strobili, only one Coleoptera (Erotylidae: Pharaxonotha) was present seasonally. Pharaxonotha cerradensis was the single species capable of transporting pollen and developing a life cycle associated with polleniferous strobili, while concomitantly visiting ovuliferous strobili. Experimental tests associated with observational evidence in the cycad indicated brood‐site pollination mutualism with the Erotylidae beetle, a potential pollinator of Z. boliviana. Our investigation confirmed a new case of obligatory mutualism between cycads and P. cerradensis in the New World. Future research on Zamia from South America should address pollination systems of this genus to better understand the ecology and evolution of plant–pollinator interactions.
COVID‐19 and the shifting industrial landscape
Authors: Gibson Chris , Carr Chantel , Lyons Craig , Taksa Lucy , Warren Andrew
Published: March 2021

The COVID‐19 coronavirus pandemic has fuelled debate about domestic industry and manufacturing in light of shocks to global supply chains and shortages of medical and personal protective equipment (PPE). Nevertheless, debates have been poorly attuned to geography and history. Calls for reinvigorated domestic manufacturing conceal the degree to which industrial landscapes are already entwined in geometries of power. This is especially so at ports—increasingly privatised—that have become sites of policy focus and biosecurity panic. Crucial trading zones, ports are being refashioned as growth machines for commodity export, energy, and logistics, undergirding national manufacturing capacity via trade and material commodity flows. Yet ports have also always been vectors for disease transmission and are central places for COVID‐19 crises. Writing from Port Kembla, south of Sydney, Australia, we catalogue five themes warranting geographical analysis and global comparison in light of coronavirus: disruptions to supply chains (with implications for global production networks); domestic industrial capacity and the future of manufacturing; biosecuring industrial sites; precarious labour and work; and vernacular emergency response capacities within industrial communities. Amidst heightened geopolitical tensions, geographers reveal how industrial landscapes are contested. Logistical and biosecurity roles are enveloped by enduring infrastructural materialities, local histories, and regional legacies of skill and ingenuity.
Genomic scan revealed KIT gene underlying white/gray plumage color in Chinese domestic geese
Authors: Wen J. , Shao P. , Chen Y. , Wang L. , Lv X. , Yang W. , Jia Y. , Jiang Z. , Zhu B. , Qu L.
Published: March 2021

Goose is an important type of domesticated poultry. The wild geese that are regarded as the ancestors of modern domestic geese present gray plumage. Domesticated, geese have both white and gray feathers. To elucidate the genetic mechanisms underlying the formation of white and gray plumage in geese, we resequenced the whole genome of 18 geese from six populations including white and gray goose breeds. The average sequencing depth per individual was 9.81× and the average genome coverage was 96.8%. A total of 346 genes were detected in the top 1% of FST scores of gray‐ and white‐feathered geese, and a significant FST site was located in the intron region within the KIT gene, the 18 bp deletion in KIT having the strongest potential association with white feathers. It has been reported that a number of genes are associated with plumage colors in birds. However, no studies have identified the relationship between KIT and plumage color in birds at present, although the white coat can be attributed to mutations in KIT in some mammals. Our study showed that that KIT is a plausible candidate gene for white/gray plumage color in Chinese domestic geese.