Smoothed Particle Hydrodynamics for Navier-Stokes Fluid Flow Application

The aim of this publication is to introduce the particle based computational fluid dynamics (CFD) method smoothed particle hydrodynamics (SPH) and introduce an applicable and valid SPH implementation for practical cases. For this purpose, current research approaches are combined regarding performance and numerical stability.  The principles of the method, the mathematical basics and the discretization of the Navier-Stokes equations are clarified. Furthermore, the implementation of method-specific boundary conditions, wall, inlet and outlet, as well as several correction procedures and a surface tension setup into the present code framework are described. The advantages and validity of the method are shown based on different cases. The free surface fluid behavior of a dam break is compared to experimental data of the time dependent water level of selected positions. A Karman vortex street is validated by its Strouhal number for different Reynolds numbers. The frequency of an oscillating drop is analysed and compared to the analytical solution.  The SPH is utilized for pipe flows influenced by a backward facing step and shows an expected qualitative flow field

The level of origin firing inversely affects the rate of replication fork progression

DNA damage slows DNA synthesis at replication forks; however, the mechanisms remain unclear. Cdc7 kinase is required for replication origin activation, is a target of the intra-S checkpoint, and is implicated in the response to replication fork stress. Remarkably, we found that replication forks proceed more rapidly in cells lacking Cdc7 function than in wild-type cells. We traced this effect to reduced origin firing, which results in fewer replication forks and a consequent decrease in Rad53 checkpoint signaling. Depletion of Orc1, which acts in origin firing differently than Cdc7, had similar effects as Cdc7 depletion, consistent with decreased origin firing being the source of these defects. In contrast, mec1-100 cells, which initiate excess origins and also are deficient in checkpoint activation, showed slower fork progression, suggesting the number of active forks influences their rate, perhaps as a result of competition for limiting factors

Common barriers, but temporal dissonance: Genomic tests suggest ecological and paleo‐landscape sieves structure a coastal riverine fish community

Assessments of spatial and temporal congruency across taxa from genetic data provide insights into the extent to which similar processes structure communities. However, for coastal regions that are affected continuously by cyclical sea‐level changes over the Pleistocene, congruent interspecific response will not only depend upon codistributions, but also on similar dispersal histories among taxa. Here, we use SNPs to test for concordant genetic structure among four codistributed taxa of freshwater fishes (Teleostei: Characidae) along the Brazilian Atlantic coastal drainages. Based on population relationships and hierarchical genetic structure analyses, we identify all taxa share the same geographic structure suggesting the fish utilized common passages in the past to move between river basins. In contrast to this strong spatial concordance, model‐based estimates of divergence times indicate that despite common routes for dispersal, these passages were traversed by each of the taxa at different times resulting in varying degrees of genetic differentiation across barriers with most divergences dating to the Upper Pleistocene, even when accounting for divergence with gene flow. Interestingly, when this temporal dissonance is viewed through the lens of the species‐specific ecologies, it suggests that an ecological sieve influenced whether species dispersed readily, with an ecological generalist showing the highest propensity for historical dispersal among the isolated rivers of the Brazilian coast (i.e., the most recent divergence times and frequent gene flow estimated for barriers). We discuss how our findings, and in particular what the temporal dissonance, despite common geographic passages, suggest about past dispersal structuring coastal communities as a function of ecological and paleo‐landscape sieves.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154255/1/mec15357_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154255/2/mec15357.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154255/3/mec15357-sup-0001-Supinfo.pd

Pequenos produtores de Tomé-Açu e Viseu, Pará: da "agricultura de toco" a SAFs, uma mudança possível?

Há uma grande diferença entre os pequenos agricultores de Viseu que se dedicam as culturas anuais e reduzida pecuária com os de Tomé-Açu com a adoção de SAFs. O papel dos cultivos perenes no aumento da renda e da sustentabilidade é inegável, desde que tenham mercados e possibilidade de beneficiamento. Verifica-se, também, uma maior produção coletiva de conhecimentos em Tomé-Açu, baseado em erro acerto, da curiosidade, da compreensão do ambiente e da adoção da experiência dos agricultores nipo-paraenses. A despeito dos SAFs em Tomé-Açu, os dois municípios apresentam níveis de pobreza similares, indicando que a riqueza gerada não está sendo internalizada no município e, em Viseu a sobrevivência depende das fortes transferências governamentais. A transformação dos pequenos produtores de Viseu, como de outros municípios paraenses, com a adoção de SAFs é possível, necessita de aprendizado, leva tempo (10 a 20 anos) para a sua consolidação, paciência e disciplina, mas é importante iniciar.SOBER 2018

International consensus statement on allergy and rhinology: Allergic rhinitis – 2023

Background: In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document. Methods: ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work. Results: ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost. Conclusion: The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment

†Kenyaichthyidae fam. nov and †Kenyaichthys gen. nov - First Record of a Fossil Aplocheiloid Killifish (Teleostei, Cyprinodontiformes)

The extant Cyprinodontiformes (killifishes) with their two suborders Cyprinodontoidei and Aplocheiloidei represent a diverse and well-studied group of fishes. However, their fossil record is comparatively sparse and has so far yielded members of the Cyprinodontoidei only. Here we report on cyprinodontiform fossils from the upper Miocene Lukeino Formation in the Tugen Hills of the Central Rift Valley of Kenya, which represent the first fossil record of an aplocheiloid killifish. A total of 169 specimens - mostly extraordinarily well preserved and a sample of ten extant cyprinodontiform species were studied on the basis of morphometrics, meristics and osteology. A phylogenetic analysis using PAUP was also conducted for the fossils. Both the osteological data and the phylogenetic analysis provide strong evidence for the assignment of the fossils to the Aplocheiloidei, and justify the definition of the new family dagger Kenyaichthyidae, the new genus dagger Kenyaichthys and the new species dagger K. kipkechi sp. nov. The phylogenetic analysis unexpectedly places dagger Kenyaichthys gen. nov. in a sister relationship to the Rivulidae (a purely Neotropical group),a probable explanation might be lack of available synapomorphies for the Rivulidae, Nothobranchiidae and Aplocheilidae. The specimens of dagger K. kipkechi sp. nov. show several polymorphic characters and large overlap in meristic traits, which justifies their interpretation as a species flock in statu nascendi. Patterns of variation in neural and haemal spine dimensions in the caudal vertebrae of dagger Kenyaichthys gen. nov. and the extant species studied indicate that some previously suggested synapomorphies of the Cyprinodontoidei and Aplocheiloidei need to be revised