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This article is a Commentary on Schoonderwoerd & Friedman (2021), 232: 523–536.

Background : Emerging pathogens such as Zika, chikungunya, Ebola, and dengue viruses are serious threats to national and global health security. Accurate forecasts of emerging epidemics and their severity are critical to minimizing subsequent mortality, morbidity, and economic loss. The recent introduction of chikungunya and Zika virus to the Americas underscores the need for better methods for disease surveillance and forecasting. Methods : To explore the suitability of current approaches to forecasting emerging diseases, the Defense Advanced Research Projects Agency (DARPA) launched the 2014–2015 DARPA Chikungunya Challenge to forecast the number of cases and spread of chikungunya disease in the Americas. Challenge participants ( n =38 during final evaluation) provided predictions of chikungunya epidemics across the Americas for a six-month period, from September 1, 2014 to February 16, 2015, to be evaluated by comparison with incidence data reported to the Pan American Health Organization (PAHO). This manuscript presents an overview of the challenge and a summary of the approaches used by the winners. Results : Participant submissions were evaluated by a team of non-competing government subject matter experts based on numerical accuracy and methodology. Although this manuscript does not include in-depth analyses of the results, cursory analyses suggest that simpler models appear to outperform more complex approaches that included, for example, demographic information and transportation dynamics, due to the reporting biases, which can be implicitly captured in statistical models. Mosquito-dynamics, population specific information, and dengue-specific information correlated best with prediction accuracy. Conclusion : We conclude that with careful consideration and understanding of the relative advantages and disadvantages of particular methods, implementation of an effective prediction system is feasible. However, there is a need to improve the quality of the data in order to more accurately predict the course of epidemics.

The interaction of large- and small-scale velocity fluctuations between a street canyon flow and the overlying boundary layer, under the influence of a local morphological model and a single upstream tall building, is investigated. The experiments are conducted in a wind tunnel, using Stereoscopic Particle Image Velocimetry (S-PIV) and Hot-Wire Anemometry (HWA). The Proper Orthogonal Decomposition-Linear Stochastic Estimation (POD-LSE) method is applied to decompose the velocity fluctuation scales and estimate the large-scale fluctuations at a high frequency. The amplitude modulation mechanism, which was found to exist for both smooth and homogeneous rough wall boundary layers in previous studies, still applies to the more complex morphological model with a single upstream building having a relative low height, but with some modification. When the upstream building is much higher than the surrounding buildings, the large eddies shed from the tall building may predominate the scale interaction.

This paper investigates the influence of near-bank vegetation patches on the bed morphological adjustment in open channel flow systems. The 2D depth-averaged hydro-morphological model is adopted for this investigation, which is first validated by laboratory experimental data measured in an open channel with a single near-bank vegetation patch. The validated model is then applied for extensive numerical simulations, with the aim of conducting a systematic analysis of the influence of different geometric controlling parameters on the bed morphological evolution. The controlling parameters taken into account for numerical analysis include the angle of repose value (RAV) of sediment, vegetation density (VD), patch length (PL) and patch width (PW). The numerical results and analysis show that: (1) the RAV of sediment with slope-failure parametrization only influences the shape of the transverse bed topography in the junction region; (2) increase in VD, PL and PW that substantially enhances flow blockage effect encourages the growth of the pool adjacent to the patch in three dimensions; (3) increase in VD, PL and PW produces analogous retrogressive erosion (erosion toward the upstream) in the pool region, presumably due to the increase in flow resistance. Additional numerical experiments suggest that the staggered-order distribution of multiple patches might be an optimal choice for channel restoration and conservation since pools and riffles with larger scales can be produced.

The radial dimension expands during central nervous system development after the proliferative neuroepithelium is molecularly patterned. The process is associated with neurogenesis, radial glia scaffolding and migration of immature neurons into the developing mantle stratum. Radial histogenetic units, defined as a delimited neural polyclone whose cells share the same molecular profile, are molded during these processes, and usually become roughly stratified into periventricular, intermediate and superficial (subpial) strata wherein neuronal cell types may differ and be distributed in various patterns. Cell-cell adhesion or repulsion phenomena together with interaction with local intercellular matrix cues regulate the acquisition of nuclear, reticular or layer histogenetic forms in such strata. Finally, progressive addition of inputs and outputs soon follows the purely neurogenetic and radial migratory phase. Frequently there is heterochrony in the radial development of adjacent histogenetic units, apart of peculiarities in differentiation due to non-shared aspects of the respective molecular profiles. Tangential migrations may add complexity to radial unit cytoarchitecture and function. The study of the contributions of such genetically controlled radial histogenetic units to emerging complex neural structure is a key instrument to understand central nervous system morphology and function. One recent example in this scenario is the recently proposed radial model of the mouse pallial amygdala. This is theoretically valid generally in mammals (Garcia-Calero et al., 2020), and subdivides the nuclear complex of the pallial amygdala into five main radial units. The approach applies a novel ad hoc amygdalar section plane, given the observed obliquity of the amygdalar radial glial framework. The general relevance of radial unit studies for clarifying structural analysis of all complex brain regions such as the pallial amygdala is discussed, with additional examples.

Phylogenetic divergence-time estimation has been revolutionized by two recent developments: 1) total-evidence dating (or \"tip-dating\") approaches that allow for the incorporation of fossils as tips in the analysis, with their phylogenetic and temporal relationships to the extant taxa inferred from the data and 2) the fossilized birth-death (FBD) class of tree models that capture the processes that produce the tree (speciation, extinction, and fossilization) and thus provide a coherent and biologically interpretable tree prior. To explore the behavior of these methods, we apply them to marattialean ferns, a group that was dominant in Carboniferous landscapes prior to declining to its modest extant diversity of slightly over 100 species. We show that tree models have a dramatic influence on estimates of both divergence times and topological relationships. This influence is driven by the strong, counter-intuitive informativeness of the uniform tree prior, and the inherent nonidentifiability of divergence-time models. In contrast to the strong influence of the tree models, we find minor effects of differing the morphological transition model or the morphological clock model. We compare the performance of a large pool of candidate models using a combination of posterior-predictive simulation and Bayes factors. Notably, an FBD model with epoch-specific speciation and extinction rates was strongly favored by Bayes factors. Our best-fitting model infers stem and crown divergences for the Marattiales in the mid-Devonian and Late Cretaceous, respectively, with elevated speciation rates in the Mississippian and elevated extinction rates in the Cisuralian leading to a peak diversity of ∼2800 species at the end of the Carboniferous, representing the heyday of the Psaroniaceae. This peak is followed by the rapid decline and ultimate extinction of the Psaroniaceae, with their descendants, the Marattiaceae, persisting at approximately stable levels of diversity until the present. This general diversification pattern appears to be insensitive to potential biases in the fossil record; despite the preponderance of available fossils being from Pennsylvanian coal balls, incorporating fossilization-rate variation does not improve model fit. In addition, by incorporating temporal data directly within the model and allowing for the inference of the phylogenetic position of the fossils, our study makes the surprising inference that the clade of extant Marattiales is relatively young, younger than any of the fossils historically thought to be congeneric with extant species. This result is a dramatic demonstration of the dangers of node-based approaches to divergence-time estimation, where the assignment of fossils to particular clades is made a priori (earlier node-based studies that constrained the minimum ages of extant genera based on these fossils resulted in much older age estimates than in our study) and of the utility of explicit models of morphological evolution and lineage diversification.

Drosophila melanogaster ( D. melanogaster ) is an imperative genomic model organism that is employed widely in healthcare and biological research works. Roughly 61% of recognized human genes have a perceptible similarity with the genetic code of D. melanogaster flies, besides 50% of its protein structures have mammalian equivalents. In recent times, numerous studies have been done in D. melanogaster to investigate the functions of particular genes that are available in its central nervous system, including the major organs like the heart, liver and kidney. The findings of these research works through D. melanogaster are utilized as a key mechanism to explore human interrelated diseases. However, it is essential to recognize the male and female Drosophila flies for the better understanding of human disease related studies, and it is a tricky job. This paper describes a unique programmed system to categorize the gender of D. melanogaster from the ventral view portraits captured through microscope. The proposed method includes image segmentation of the body of D. melanogaster in the form of a binary image and the construction of a continuous morphological model based on its skeleton. An analysis of the skeleton makes it possible to assess the sharpness of the caudal end of the D. melanogaster abdomen through a detailed assessment of the curvature. Based on this assessment, a Drosophila melanogaster Gender (DMG) classifier is constructed for the gender determination of D. melanogaster flies. The accuracy of the DMG classifier is about 98% in proportion to the existing state-of-the-art shape-based classifiers with optimal computing time.

Adult-born dentate granule cells (abGCs) exhibit a critical developmental phase during function integration. The time window of this phase is debated and whether abGCs become indistinguishable from developmentally born mature granule cells (mGCs) is uncertain. We analyzed complete dendritic reconstructions from abGCs and mGCs using viral labeling. AbGCs from 21–77 days post intrahippocampal injection (dpi) exhibited comparable dendritic arbors, suggesting that structural maturation precedes functional integration. In contrast, significant structural differences were found compared to mGCs: AbGCs had more curved dendrites, more short terminal segments, a different branching pattern, and more proximal terminal branches. Morphological modeling attributed these differences to developmental dendritic pruning and postnatal growth of the dentate gyrus. We further correlated GC morphologies with the responsiveness to unilateral medial perforant path stimulation using the immediate–early gene Arc as a marker of synaptic activation. Only abGCs at 28 and 35 dpi but neither old abGCs nor mGCs responded to stimulation with a remodeling of their dendritic arbor. Summarized, abGCs stay distinct from mGCs and their dendritic arbor can be shaped by afferent activity during a narrow critical time window.

The individual’s posture is the physical expression of his body. It is modified throughout life and it is determined by the particular anatomical characteristics that directly affect the biomechanics of the spine. The typing of the spinal curvature is important for the knowledge of body posture. The possibility of having a method for the systematic postural characterization of the spine is an essential objective resource in order to obtain normal or control patterns of the spinal morphology of the population. A widely accepted methodology of morphological characterization of the spine is a necessary requirement for the establishment of preventive criteria for spinal pathologies based on epidemiological population studies. It also represents a necessary requirement for the classification of individuals, based on the biomechanical, orthopaedic or ergonomic criteria necessary for disciplines such as sports, industrial design or sports performance. The present study proposes the development of a morphological postural model of the spine in the lumbar region. The model is based on a system of measurement of objective and comparable parameters by means of X-ray analysis, in order to characterize its morphology in the sagittal plane. The comparison of the results in a population of 47 individuals allowed the possibility to carry out a statistical study on three morphological parameters: sacral angle (α1); reversal angle (α2) and degree of lordosis (DL). The statistical hypothesis that the results behave according to a normal distribution with p < 0.05 is relevant and allows the systematization and postural modelling of the individual.

Purpose. Development and testing of a model that formalizes and supports decision-making process regarding the appropriateness of using territory (geological environment) for urban underground construction. Methodology. Modified morphological analysis of urbanized territories, expert evaluation method. Findings. A morphological model and a tool set for evaluating construction sites for underground construction were tested; morphological tables were constructed; expert estimate scales for alternative values of construction site parameters were justified. Cross-consistency matrices of influence factors and parameter alternatives were evaluated. Evaluation of two sites for underground construction in Kyiv was performed using the developed model. Originality. For the first time, a morphological model of territorial development for underground city planning was designed and tested on real construction sites in Kyiv. The modified morphological analysis method was applied for risk estimation of urban development of underground space. Systemic characteristics of urban territories were obtained, which show the favorability of a site for underground construction. Practical value. Evaluation of the prospect of underground construction on the pre-project stage, capabilities for risk management of urban underground city space development, diminishing of the potential for project flaws caused by neglecting certain factors or specifics of a geological environment and technogenic impacts, convenient form of information generation as tables, charts or graphs.