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In this research, we investigate the influence of a load-balancing strategy and parametrization on the speed-up of discrete element method simulations using Lethe-DEM. Lethe-DEM is an open-source DEM code which uses a cell-based load-balancing strategy. We compare the computational performance of different cell-weighing strategies based on the number of particles per cell (linear and quadratic). We observe two minimums for particle to cell weights (at 3, 40 for quadratic, and 15, 50 for linear) in both linear and quadratic strategies. The first and second minimums are attributed to the suitable distribution of cell-based and particle-based functions, respectively. We use four benchmark simulations (packing, rotating drum, silo, and V blender) to investigate the computational performances of different load-balancing schemes (namely, single-step, frequent and dynamic). These benchmarks are chosen to demonstrate different scenarios that may occur in a DEM simulation. In a large-scale rotating drum simulation, which shows the systems in which particles occupy a constant region after reaching steady-state, single-step load-balancing shows the best performance. In a silo and V blender, where particles move in one direction or have a reciprocating motion, frequent and dynamic schemes are preferred. We propose an automatic load-balancing scheme (dynamic) that finds the best load-balancing steps according to the imbalance of computational load between the processes. Furthermore, we show the high computational performance of Lethe-DEM in the simulation of the packing of 108 particles on 4800 processes. We show that simulations with optimum load-balancing need ≈40% less time compared to the simulations with no load-balancing.

The performance of autoethnographic storytelling can amplify the voices of those who are often unheard, silenced, or marginalized. Moreover, personal storytelling in appropriate contexts can provide a forum for sharing the previously unspoken or unspeakable that, when shared, can begin to heal the teller and promote social justice and societal change. Yet, not all contexts are are appropriate and not all stories are safe to share. Thus, telling autoethnographic stories can present ethical concerns for which there are no pat answers or one-size-fits-all solutions. This article discusses a few of these concerns.

This paper provides a review of the Fractal Market Hypothesis (FMH) focusing on financial times series analysis. In order to put the FMH into a broader perspective, the Random Walk and Efficient Market Hypotheses are considered together with the basic principles of fractal geometry. After exploring the historical developments associated with different financial hypotheses, an overview of the basic mathematical modelling is provided. The principal goal of this paper is to consider the intrinsic scaling properties that are characteristic for each hypothesis. In regard to the FMH, it is explained why a financial time series can be taken to be characterised by a 1/t1−1/γ" role="presentation" style="box-sizing: border-box; max-height: none; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">1/t1−1/γ scaling law, where γ>0" role="presentation" style="box-sizing: border-box; max-height: none; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">γ>0 is the Lévy index, which is able to quantify the likelihood of extreme changes in price differences occurring (or otherwise). In this context, the paper explores how the Lévy index, coupled with other metrics, such as the Lyapunov Exponent and the Volatility, can be combined to provide long-term forecasts. Using these forecasts as a quantification for risk assessment, short-term price predictions are considered using a machine learning approach to evolve a nonlinear formula that simulates price values. A short case study is presented which reports on the use of this approach to forecast Bitcoin exchange rate values.

“Triptych,” a reflection in poetic form, does not provide or ponder easy solutions to ethical dilemmas in personal storytelling (true personal stories shared in classrooms and/or performed in public forums), but illuminates a few issues tellers, teachers, and researchers may encounter as they strive to nurture and develop true stories that give voice to a diversity of lived experiences.

Prophylactic administration of the broad-spectrum chemokine inhibitor (BSCI) FX125L has been shown to suppress uterine contraction, prevent preterm birth (PTB) induced by Group B Streptococcus in nonhuman primates, and inhibit uterine cytokine/chemokine expression in a murine model of bacterial endotoxin (LPS)-induced PTB. This study aimed to determine the mechanism(s) of BSCI action on human myometrial smooth muscle cells. We hypothesized that BSCI prevents infection-induced contraction of uterine myocytes by inhibiting the secretion of pro-inflammatory cytokines, the expression of contraction-associated proteins and disruption of myocyte interaction with tissue macrophages. Myometrial biopsies and peripheral blood were collected from women at term (not in labour) undergoing an elective caesarean section. Myocytes were isolated and treated with LPS with/out BSCI; conditioned media was collected; cytokine secretion was analyzed by ELISA; and protein expression was detected by immunoblotting and immunocytochemistry. Functional gap junction formation was assessed by parachute assay. Collagen lattices were used to examine myocyte contraction with/out blood-derived macrophages and BSCI. We found that BSCI inhibited (1) LPS-induced activation of transcription factor NF-kB; (2) secretion of chemokines (MCP-1/CCL2 and IL-8/CXCL8); (3) Connexin43-mediated intercellular connectivity, thereby preventing myocyte–macrophage crosstalk; and (4) myocyte contraction. BSCI represents novel therapeutics for prevention of inflammation-induced PTB in women.

Failures to replicate the results of scientific studies are often attributed to misinterpretations of the p value. The p value may be interpreted as an approximate posterior probability, not that the null hypothesis is true but rather that it explains the data as well as the data-generating distribution. That posterior probability modifies the p value in the following two broad areas of application, leading to new methods of hypothesis testing and effect size estimation. First, when corrected for multiple comparisons, the posterior probability that the null hypothesis adequately explains the data overcomes both the conservative bias of corrected p values and the anti-conservative bias of commonly used false discovery rate methods. Second, the posterior probability that the null hypothesis adequately explains the data, conditional on a parameter restriction, transforms the p value in such a way as to overcome difficulties in restricted parameter spaces. Keywords: multiple comparison procedures; multiple testing; null hypothesis significance testing; restricted parameter space; replication crisis; reproducibility crisis

Publishing in peer review journals is an acquired skill that almost any scholar–practitioner can achieve through a systematic approach and practice. The authors of this manuscript are experienced editors from five leading international sport and exercise psychology peer-review journals. Within this manuscript, the contributing authors considered how one could effectively proceed in the authoring process from the point of conceptualization onward to manuscript acceptance. Particular focus has been placed on journal requirements, useful content suggestions in relation to all components of a manuscript, and the revision process. A final summation is provided with key takeaway points. The intention is to further author understanding and effective authoring pathways in relation to academic publishing in any sport and exercise psychology-focused journal.

Abstract International NGOs (INGOs) are important agents in delivering the UN’s sustainable development agenda, but their linguistic practices have received little attention in the field of language policy and planning. This article aims to add new insights to the field by exploring the link between INGOs’ organisational value of inclusiveness and their institutional approaches to translation. It does so through a case study of Oxfam GB’s and Tearfund’s translation policy documents. The analysis reveals that the policy documents focus on written translation into a handful of lingua francas. In other words, they largely overlook the need for interpreting and translation from and into local languages. In addition, the policy documents do not make any overt links between principles of (linguistic) inclusiveness and the need for translation. The article summarises the advantages and drawbacks of creating a translation policy, and provides guidance on linking translation policy more overtly to values of inclusiveness.

Providing security guarantee is a critical concern in the ad-hoc networks relying on multi-hop channels, since their flexible topology is vulnerable to security attacks. To enhance the security of a spatial modulation (SM) assisted wireless network, various SM mapping patterns are activated by random channel quality indicator (CQI) patterns over the legitimate link, as a physical-layer secret key. The SM signals are encrypted by random mapping patterns to prevent eavesdroppers from correctly demapping their detections. This secret key is developed for multi-hop wiretap ad-hoc networks, where eavesdroppers might monitor all the transmitting nodes of a legitimate link. We substantially characterise the multi-hop wiretap model with receiver diversity techniques adopted by eavesdroppers. The security performance of the conceived scheme is evaluated in the scenarios where eavesdroppers attempt to detect their received signals using maximal-ratio combining or maximum-gain selection. The achievable data rates of both legitimate and wiretapper links are formulated with the objective of quantifying the secrecy rates for both Gaussian-distributed and finite-alphabet inputs. Illustrative numerical results are provided for the metrics of ergodic secrecy rate and secrecy outage probability, which substantiate the compelling benefits of the physical-layer secret key generation via CQI-mapped SM.

Computational decision-making in “real world” environmental and sustainability contexts frequently requires the need to contrast numerous uncertain factors and difficult-to-capture dimensions. Monte Carlo simulation modelling has frequently been employed to integrate the uncertain inputs and to construct probability distributions of the resulting outputs. Visual analytics and data visualization can be used to support the processing, analyzing, and communicating of the influence of multi-variable uncertainties on the decision-making process. In this paper, the novel Simulation Decomposition (SimDec) analytical technique is used to quantitatively examine carbon emission impacts resulting from a transformation of the aviation industry toward a state of greater airline electrification. SimDec is used to decompose a Monte Carlo model of the flying range of all-electric aircraft based upon improvements to batteries and motor efficiencies. Since SimDec can be run concurrently with any Monte Carlo model with only negligible additional overhead, it can easily be extended into the analysis of any environmental application that employs simulation. This generalizability in conjunction with its straightforward visualizations of complex stochastic uncertainties makes the practical contributions of SimDec very powerful in environmental decision-making.