bluuebunny/crossref_metadata_2025_split huggingface dataset:
The promise of entrepreneurship ecosystems: a conceptual model for black American entrepreneurs
Authors: Edmondson Vickie Cox , Zebal Mostaque A. , Jackson Faye Hall , Bhuiyan Mohammad A. , Crumbly Jack 
Published: November 2023

Purpose
The purpose of this paper is to set forth a conceptual model describing the actors and roles in ecosystems created to enable productive black entrepreneurship in the USA.

Design/methodology/approach
This paper provides a systematic literature review of entrepreneurship ecosystems. It further leverages such literature review by using an autoethnographic approach recommended by Guyotte and Kochacka (2016), drawing on the authors’ practical experience in studying, owning, educating or consulting employer businesses owned by persons of color in the USA and abroad.

Findings
Each actor in the ecosystem has practical wisdom and assets that can be shared and leveraged through interacting with the other actors either as role model institutions or capacity development institutions, thus mitigating social inequalities and boosting economic progress by extending entrepreneurial opportunities beyond those that are greatly resourced.

Research limitations/implications
Our literature review is based on selected samples of relevant articles on entrepreneurship ecosystem research and ethnic minority entrepreneurship, and thus, is not exhaustive. The selection was partly influenced by the authors’ opinion of whether a given study was relevant or not to a black entrepreneurship ecosystem. There is the possibility that some relevant studies were excluded. Thus, other actors are encouraged to revise or adapt this model to inform their distinct roles and goals.

Practical implications
The proposed model can help actors involved in the operation or support of a black-owned business make optimal business decisions, enabling each actor to be instrumental in another’s understanding of how to facilitate the success of black American entrepreneurs and business owners and thus, deploy marketing campaigns to boost the visibility and role of each actor. These campaigns play a role in their entrepreneurial marketing efforts.

Originality/value
Responding to Gines and Sampson’s (2020) call, to the best of the authors’ knowledge, this paper is the first to explicitly provide a comprehensive black entrepreneurship ecosystem model that identifies the actors, roles and activities that can help black Americans address social inequalities that limit their ability to become a successful employer business. The proposed model may aid in deepening the theoretical discussion on entrepreneurial ecosystems and be of inspiration for the future works of scholars and practitioners interested in the entrepreneurship and marketing interface.
Predation risk drives long‐term shifts in migratory behaviour and demography in a large herbivore population
Authors: Williams S. , Hebblewhite M. , Martin H. , Meyer C. , Whittington J. , Killeen J. , Berg J. , MacAulay K. , Smolko P. , Merrill E. H. 
Published: November 2023

Abstract

Migration is an adaptive life‐history strategy across taxa that helps individuals maximise fitness by obtaining forage and avoiding predation risk. The mechanisms driving migratory changes are poorly understood, and links between migratory behaviour, space use, and demographic consequences are rare.

Here, we use a nearly 20‐year record of individual‐based monitoring of a large herbivore, elk (Cervus canadensis) to test hypotheses for changing patterns of migration in and adjacent to a large protected area in Banff National Park (BNP), Canada.

We test whether bottom‐up (forage quality) or top‐down (predation risk) factors explained trends in (i) the proportion of individuals using 5 different migratory tactics, (ii) differences in survival rates of migratory tactics during migration and whilst on summer ranges, (iii) cause‐specific mortality by wolves and grizzly bears, and (iv) population abundance.

We found dramatic shifts in migration consistent with behavioural plasticity in individual choice of annual migratory routes. Shifts were inconsistent with exposure to the bottom‐up benefits of migration. Instead, exposure to landscape gradients in predation risk caused by exploitation outside the protected area drove migratory shifts. Carnivore exploitation outside the protected area led to higher survival rates for female elk remaining resident or migrating outside the protected area.

Cause‐specific mortality aligned with exposure to predation risk along migratory routes and summer ranges. Wolf predation risk was higher on migratory routes than summer ranges of montane‐migrant tactics, but wolf predation risk traded‐off with heightened risk from grizzly bears on summer ranges. A novel eastern migrant tactic emerged following a large forest fire that enhanced forage in an area with lower predation risk outside of the protected area.

The changes in migratory behaviour translated to population abundance, where abundance of the montane‐migratory tactics declined over time. The presence of diverse migratory life histories maintained a higher total population abundance than would have been the case with only one migratory tactic in the population.

Our study demonstrates the complex ways in which migratory populations change over time through behavioural plasticity and associated demographic consequences because of individuals balancing predation risk and forage trade‐offs.
The prediction of social catastrophes: Between necessity and contingency
Authors: Donati Pierpaolo 
Published: November 2023

AbstractThe article argues that social catastrophes are the product of networks of unsaturated social relations that lead to the exponential spread of a social evil (pandemic, poverty, desertification, etc.). In the exponential curve of catastrophe there is an inflection point where, if unsaturated social relations are saturated, the catastrophe can be halted and ultimately avoided. The inflection point can be conceived as a generative relational complex in which both necessity and contingency of social relations are at work. Necessity is due to constitutive mechanisms that are automatic and, therefore, to some extent mathematically predictable. Contingency refers to non‐automatic, in principle unpredictable relational mechanisms. However, contingency can be of two kinds. It can mean “dependence on” other factors, which can have some degree of predictability, or can be understood as the possibility of “being otherwise”, which is less predictable in its outcomes, but can also open up new opportunities to change the catastrophic trend. The reduction of the exponential curve to logistics can be expected if the networks of relationships at the inflection point are saturated in one way or another. This can be achieved by managing the contingent factors of both types in order to steer the morphogenetic processes of the social networks that configure the inflection point as a relational complex.
Optimizing net present values of risk avoidance for mountain railway alignments with seismic performance evaluation
Authors: Song Taoran , Pu Hao , Yang T. Y. , Schonfeld Paul , Li Wei , Hu Jianping 
Published: November 2023

AbstractRailway alignment optimization in earthquake‐prone mountainous (EPM) regions should quantify and trade off construction investments and seismic risks. Unfortunately, slight attention has been previously devoted to this trade‐off. To this end, based on the FEMA‐P58 methodology, a net present value (NPV) model of risk avoidance is presented and solved. In the model, alignment alternatives are first segmented into structural groups with different probabilistic seismic fragility curves, which are then used to generate structural repair cost and repair time curves. Afterward, a probabilistic seismic hazard curve is introduced to estimate the expected annual repair cost and time for computing railway direct and indirect seismic losses. Hence, the railway total annual loss caused by seismic activity can be obtained. Next, a benefit–cost analysis is performed to combine construction cost and seismic loss as the risk‐cost NPV. To optimize this objective function, a particle swarm algorithm is used as the basic approach. For implementing the probabilistic seismic performance analysis, a Monte Carlo simulation (MCS) is employed as the risk assessment module. Furthermore, due to the computationally intensive nature of MCS, a CPU‐based parallelization is embedded into the algorithm to expedite the search. Finally, the proposed model and method are applied to a representative real‐world railway case in an EPM region. Their effectiveness is discussed and verified in five experiments, including algorithm convergence analysis, alignment solution comparison, seismic risk interpretation, computational efficiency test, and a specific sensitivity analysis.
Global bounded classical solutions to a parabolic–elliptic chemotaxis model with local sensing and asymptotically unbounded motility
Authors: Jiang Jie , Laurençot Philippe 
Published: November 2023

AbstractGlobal existence and boundedness of classical solutions are shown for a parabolic–elliptic chemotaxis system with local sensing when the motility function is assumed to be unbounded at infinity. The cornerstone of the proof is the derivation of ‐estimates on the second component of the system and is achieved by various comparison arguments.
Printed Circuit Board Defect Image Recognition Based on the Multimodel Fusion Algorithm
Authors: Zhang Jiantao , Chang Zhengfang , Xu Haida , Qu Dong , Shi Xinyu 
Published: November 2023

Abstract
Printed Circuit Board (PCB) is one of the most important components of electronic products. But the traditional defect detection methods are gradually difficult to meet the requirements of PCB defect detection. The research on PCB defect recognition method based on convolutional neural network is the current trend. The PCB defect image recognition based on DenseNet169 network model is studied in this paper. In order to reduce the omission of PCB defects in actual detection, it is necessary to further improve the sensitivity of the model. Therefore, a classification model based on the multimodel fusion of the DenseNet169 model and the ResNet50 model is proposed. At the same time, the network structure after multimodel fusion is improved. The improved multimodel fusion model Mix-Fusion enables the network to not only retain the recognition accuracy of the ResNet50 model for NG defects and small defect images but also improve the overall recognition accuracy through the feature reuse and bypass settings of the DenseNet169 model. The experimental results show that when the threshold is 0.5, the sensitivity of the improved multimodel fusion network can reach 99.2%, and the specificity is 99.5%. The sensitivity of Mix-Fusion is 1.2% higher than that of DenseNet169. High sensitivity means fewer missed NG images, and high specificity means less workload for employees. The improved model improves sensitivity and maintains high specificity.
Heat Dissipation Design Based on Topology Optimization and Auxiliary Materials
Authors: Chen Jiawei , Yan Zhongming , Qiao Yang , Lin Feihong , Wang Yu , Zhou Hongcheng 
Published: November 2023

Abstract
In this paper, a variable density topology optimization method is used to design a high thermal conductivity path structure for efficient heat dissipation. The temperature and stiffness in the module volume are taken as the objective function. Simulations are carried out to compare with a high-power electronics device heat dissipation. The heat dissipation performance (HDP) of structures optimized topologically is further enhanced through the use of auxiliary materials, including highly thermally conductive coating material and phase change material (PCM). The efficient heat dissipation of the constructed topology optimization model and the effectiveness of the proposed method are verified.
Localized Blowing for Near-Wake Flow and Vortical Structure Control in Turbulent Boundary Layers Over Periodic Two-Dimensional Roughness
Authors: Hamed Ali M. , Gallary Ryan M. , McAtee Bailey R. 
Published: November 2023

Abstract
Volumetric three-component flow measurements were made to investigate localized blowing (injection) as a control strategy for turbulent boundary layers over k-type two-dimensional (2D) roughness. The flow measurements were made using particle tracking velocimetry at a Reynolds number of 100,000, based on the freestream velocity and boundary layer thickness. The roughness occupied ∼13% of the boundary layer thickness and consisted of transverse square bars positioned periodically at a pitch-to-height ratio of 11. Two cases were considered: a baseline case without blowing and a case with blowing through five spanwise jets issuing from the downstream face of the 11th bar. The results highlight the effectiveness of blowing in reducing the size of the recirculation zone and turbulence past the bar. Specifically, the spanwise-averaged flow field for the blowing case shows a 40% reduction in the reattachment length and ∼25% reduction in the maximum Reynolds shear stress relative to the baseline case. Moreover, visualizations of the vortical structures past the bars for the baseline case display coherent spanwise vortices similar to those observed past isolated 2D bars and backward-facing steps; however, the spanwise vortices observed here exhibit more three-dimensionality likely due to the turbulence enhanced by upstream bars. Blowing disrupts these spanwise vortices and produces new vortical structures with a wall-normal sense of rotation, although significantly weaker than the spanwise vortices. As such, blowing results in a reduction in the spanwise-averaged spanwise vorticity characteristic of the flow over k-type 2D roughness. The disruption of the spanwise vortices and the reduction in the size of the recirculation zone are likely responsible for the reduction in the Reynolds shear stress and turbulent kinetic energy in the near wake.
What a Wave Buoy Actually Measures in 3D: Analysis of a Mild Sea State
Authors: Ding Yue , Taylor Paul H. , Zhao Wenhua , Dory Jean-Noel 
Published: November 2023

Abstract
Measurements of surface waves from oceanographic buoys have been regarded as the “ground truth” for validation of sea-state prediction models, providing the basis for input to the design of offshore structures. The engineering practice is to produce wave statistics of vertical surface displacements over periods of years. However, a wave buoy can provide simultaneous time histories of its motion, one vertically and the other two horizontally, giving the complete vector displacement field in time. We investigate the measured time histories of a wave buoy in three orthogonal directions and explore the relationship between them, for a relatively benign, so typical, sea state. We adopt a NewWave-type analysis to investigate the average shape of the large events across the measured time histories. In combination with a conditioning analysis, we give a reciprocity relationship between the vertical displacement of the wave buoy and those in the horizontal plane. The relationship is of value, as it allows for the prediction of wave kinematics in the horizontal plane based on the vertical measurement only. We observe significant second-order components in the measured data in the horizontal directions and smaller contributions vertically. This data-driven analysis paves the way for wave-by-wave prediction and the active control of wave energy converters and personnel transfers offshore.
Modeling of recovery efficiency of sampling devices used in planetary protection bioburden estimation
Authors: DiNicola Michael , Seuylemezian Arman , Guan Lisa , Moissl-Eichinger Christine , Baker Amy , Johns Jason 
Published: November 2023

ABSTRACT
Planetary protection is a discipline dedicated to preventing biological contamination between celestial bodies and Earth during space exploration to ensure the integrity of scientific research. National space agencies such as the National Aeronautics and Space Administration and the European Space Agency set biological cleanliness requirements for their missions based on the guidelines provided in The Committee on Space Research’s Planetary Protection Policy. Compliance with these requirements is often demonstrated by surface sampling of spacecraft hardware and associated surfaces to enumerate the number of microorganisms present and establish that they are below the required level. The discipline has employed a variety of tools to perform sampling; the recovery efficiency of which is a key parameter used to generate spacecraft level cleanliness estimates. In this study, we investigated how recovery efficiency differs by inoculum amount and species. This was analyzed across different sampling devices using a set of microorganisms applied to stainless steel surfaces (representative of spacecraft surfaces) and two processing methods. Data were analyzed by developing a probabilistic model of the experimental process, from stainless steel coupon inoculation through recovery of spores observed in the form of colony forming units. The model quantifies the probability that an individual spore is recovered, a key metric for predicting bioburden and statistically assessing bioburden requirements. A cost function was developed to identify those assay methods that provided optimal bioburden estimation capability. Results show the nylon-flocked swab and the TX3211 wipe yield the highest recovery efficiency of those tested.

IMPORTANCE

Planetary protection at the National Aeronautics and Space Administration (NASA) requires bioburden on certain spacecraft to be estimated via sampling in order to comply with biological cleanliness requirements. To achieve this, the recovery efficiency of devices used to sample the spacecraft pre-launch must be understood and their uncertainty quantified in order to produce the most reasonable estimates of bioburden. This study brings together experiments performed by NASA and the European Space Agency with approved swab and wipe sampling devices, inoculating steel coupons with laboratory strains of
Bacillus
spp. spores commonly recovered from spacecraft assembly clean rooms (
B. atrophaeus
,
B. megaterium
,
B. safensis
and
B. thuringiensis
), with a mathematical model of the assay process to assess recovery efficiency. The statistical treatment developed in this study allows comparison of bioburden estimates made from different devices processed by different methods. This study also gives stakeholders and practitioners a statistically rigorous approach to predict bioburden that can be folded into future modeling efforts.
Pantailocins: phage-derived bacteriocins from
Pantoea ananatis
and
Pantoea stewartii
subsp.
indologenes
Authors: Stice Shaun P. , Jan Hsiao-Hsuan , Chen Hsiao-Chun , Nwosu Linda , Shin Gi Yoon , Weaver Savannah , Coutinho Teresa , Kvitko Brian H. , Baltrus David A. 
Published: November 2023

ABSTRACT

Phage-derived bacteriocins are highly specific and effective antimicrobial molecules, which have successfully been used as prophylactic treatments to prevent phytopathogen infections. Given the specificity of tailocins, a necessary step for broadening the tailocin catalog and for extending applicability across systems and diseases is the screening of new clades of phytopathogens for the production of molecules with tailocin-like killing activity. Here, we describe the production by and sensitivity of strains to tailocins produced by
Pantoea ananatis
and
Pantoea stewartii
subsp.
indologenes
. Phylogenetic evidence suggests that these tailocins are derived from Myoviridae family phage like many previously described R-type tailocins but also suggests that cooption from phage occurred independently of previously described tailocins. Since these tailocin encoding loci are present in the same genomic locations across multiple strains of both species and display a level of divergence that is consistent with other shared regions between the genomes and with vertical inheritance of the locus, we refer to them broadly as “Pantailocins.”

IMPORTANCE

Phage-derived bacteriocins (tailocins) are ribosomally synthesized structures produced by bacteria in order to provide advantages against competing strains under natural conditions. Tailocins are highly specific in their target range and have proven to be effective for the prevention and/or treatment of bacterial diseases under clinical and agricultural settings. We describe the discovery and characterization of a new tailocin locus encoded within genomes of
Pantoea ananatis
and
Pantoea stewartii
subsp.
indologenes
, which may enable the development of tailocins as preventative treatments against phytopathogenic infection by these species.
In vitro
digestion of SARS-CoV-2 contaminated berries reveals high inactivation of infectious virus during gastrointestinal passage
Authors: Esseili Malak A. 
Published: November 2023

ABSTRACT

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infectivity was shown to be stable on frozen berries for at least a month; however, whether the virus on berries remains infectious as it passes through the gastrointestinal tract is unknown. Here, the stability of SARS-CoV-2 infectivity on berries under
in vitro
digestion was investigated. The INFOGEST (an international network of excellence on the fate of food in the gastrointestinal tract) and the biorelevant fast- and fed-state models were used. SARS-CoV-2 (~7 log 50% tissue culture infective dose [TCID
50
]/mL) infectivity was assessed in blueberry and strawberry homogenates at 4°C and 37°C, and following consecutive oral (2 min), gastric (10 and 60 min), and intestinal (15 and 120 min) digestion at 37°C. SARS-CoV-2 infectivity was quantified on Vero-E6 cell line using the TCID
50
assay. SARS-CoV-2 infectivity in berry homogenates was stable for 120 min at 4°C; however, the virus was completely inactivated at 37°C within 60 min. The biorelevant fed-state model closely mimicked the INFOGEST model. In the oral phase, SARS-CoV-2 infectivity decreased by ~1 log, which did not change during the 10-min gastric digestion. By 60 min of gastric digestion, strawberries had a protective effect on SARS-CoV-2, showing less inactivation (~2 log) in comparison to blueberries (~3–3.4 log). The viruses entering the intestinal phase showed a 2.6–3.3 log inactivation within 15 min. In contrast, SARS-CoV-2 in the fast-state model showed high inactivation at the 10- and 15-min gastric and intestinal time points (2.5 and 4 log, respectively). Therefore, under high levels of SARS-CoV-2 contamination of berries, it is possible for the virus to infect the oral cavity but less likely to infect the intestine.

IMPORTANCE

During the pandemic, news outlets occasionally reported on the detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA on various foods, raising concerns over contaminated foods initiating infections. Coronavirus disease 2019 (COVID-19) patients often experience gastrointestinal symptoms and shed SARS-CoV-2 RNA in their feces. In addition, active virus replication in the gastrointestinal tract was shown; however, infectious viruses were rarely detected in feces. We previously showed that SARS-CoV-2 remained infectious on frozen berries for at least a month. Here,
in vitro
digestion models showed that SARS-CoV-2 on berries exhibits minimal inactivation at the oral phase and the virus may escape gastric inactivation early during feeding. However, high intestinal inactivation of the virus on berries suggested that SARS-CoV-2 was less likely to initiate infection in the small intestine. In contrast, the oral cavity is a potential site where infection might be initiated, providing more input for the gastrointestinal tract. High intestinal inactivation might explain the difficulty of detecting infectious SARS-CoV-2 in feces but not of virus RNA.