The oral cavity is a vital part of the digestive system. Poor oral health can impact an individual’s ability to eat and has been associated with increased risk of non-communicable diseases and reduced longevity. Conversely, positive oral health has been associated with improved cardiometabolic, cognitive and systemic health and greater longevity. Consumption of dietary nitrate, which is processed in the mouth into nitrite, and is subsequently converted into nitric oxide (NO) in the body (1), has been demonstrated to reduce blood pressure, improve endothelial function, and enhance exercise performance. Interestingly, recent studies suggest that nitrate consumption could also positively modulate markers of oral health (2). To our knowledge, no systematic review has been published examining the effect of inorganic dietary nitrate on oral health. However, this could be valuable to summarise current state of the knowledge, identify effect modifiers and highlight gaps for future research. Therefore, this systematic review aims to investigate the effects of dietary nitrate supplements on markers of oral health in vivo in randomised controlled trials (RCTs).

This study was pre-registered with PROSPERO (CRD42023411159). Five databases (PubMed, The Cochrane Library, CINAHL, MEDLINE, and SPORTDiscus) were searched from inception until March 2023 to identify studies that met the following criteria: adult participants (≥ 18 years) and RCTs investigating the effects of oral dietary nitrate versus placebo on markers of oral health. A narrative synthesis of data was conducted. Risk of bias was assessed using the Cochrane Risk of Bias 2 tool.

Nine articles reporting data on 284 participants were included. Nitrate was provided via beetroot juice (six studies), a beetroot-derived supplement dissolved in mineral water (one study), and lettuce juice (two studies). The duration of the interventions ranged from one day to a maximum of six weeks. Dietary nitrate supplementation increased the relative abundance of several individual bacterial genera including Neisseria (increased in three studies) and Rothia (increased in three studies). Dietary nitrate supplementation increased salivary pH (increased in two studies) and decreased salivary acidification resulting from the consumption of a sugar-sweetened beverage (decreased in two studies). Furthermore, dietary nitrate supplementation resulted in a decrease in the gingival inflammation index in one study. Overall, the risk of bias in studies was mixed. One study had a low risk of bias, while the rest were rated as having some concerns. No study was considered to have a high risk of bias.

The results show that dietary nitrate is a potential nutritional strategy that can potentially benefit oral health by modifying the oral microbiome, altering salivary pH, and minimising gingival inflammation.

Laser-directed energy deposition (L-DED) is a key enabling technology for the repair of high-value aerospace components, as damaged regions can be removed and replaced with additively deposited material. While L-DED repair improves strength and fatigue performance compared to conventional subtractive techniques, mechanical performance can be limited by process-related defects. To assess the role of oxygen on defect formation, local and chamber-based shielding methods were applied in the repair of 300M high strength steel. Oxidation between layers for locally shielded specimens is confirmed to cause large gas pores which have deleterious effects on fatigue life. Such pores are eliminated for chamber shielded specimens, resulting in an increased ductility of ∼15%, compared to ∼11% with chamber shielding. Despite this, unmelted powder defects are not affected by oxygen content and are found in both chamber- and locally shielded samples, which still have negative consequences for fatigue.

We investigate the statistics of turbulence in emulsions of two immiscible fluids of the same density. We compute velocity increments between points conditioned to be located in the same phase or in different phases, and examine their probability density functions (PDFs) and the associated structure functions (SFs). This enables us to demonstrate that the presence of the interface reduces the skewness of the PDF at small scales and therefore the magnitude of the energy flux towards the dissipative scales, which is quantified by the third-order SF. The analysis of the higher-order SFs shows that multiphase turbulence is more intermittent than single-phase turbulence. In particular, the local scaling exponents of the SFs display a saturation below the Kolmogorov–Hinze scale, which indicates the presence of large velocity gradients across the interface. Interestingly, the statistics of the velocity differences in the carrier phase recovers that of single-phase turbulence when the viscosity of the dispersed phase is high.

Pteridinium simplex is an iconic erniettomorph taxon best known from late Ediacaran successions in South Australia, Russia, and Namibia. Despite nearly 100 years of study, there remain fundamental questions surrounding the paleobiology and paleoecology of this organism, including its life position relative to the sediment–water interface, and how it fed and functioned within benthic communities. Here, we combine a redescription of specimens housed at the Senckenberg Forschungsinstitut und Naturmuseum Frankfurt with field observations of fossiliferous surfaces, to constrain the life habit of Pteridinium and gain insights into the character of benthic ecosystems shortly before the beginning of the Cambrian. We present paleontological and sedimentological evidence suggesting that Pteridinium was semi-infaunal and lived gregariously in aggregated communities, preferentially adopting an orientation with the long axis perpendicular to the prevailing current direction. Using computational fluid dynamics simulations, we demonstrate that this life habit could plausibly have led to suspended food particles settling within the organism's central cavity. This supports interpretation of Pteridinium as a macroscopic suspension feeder that functioned similarly to the coeval erniettomorph Ernietta, emblematic of a broader paleoecological shift toward benthic suspension-feeding strategies over the course of the latest Ediacaran. Finally, we discuss how this new reconstruction of Pteridinium provides information concerning its potential relationships with extant animal groups and state a case for reconstructing Pteridinium as a colonial metazoan.

This article presents a data-driven model based on modal decomposition, applied to approximate the low-order statistics of the spatially averaged wall-shear stress in a turbulent channel flow over a porous wall with two anisotropic permeabilities, producing drag increase or reduction when compared with the case of an isotropic porous wall. The model is comparable to a neural network architecture using a linear map to a classification. To create this model, we use high-order dynamic mode decomposition (DMD) to identify the structures describing the main flow dynamics, and then test different linear combinations of these modes to estimate the time evolution of the stress at the porous interface. The coefficients of the model are obtained by training the model against the results of direct numerical simulations over different time intervals. Depending on the number and the way of combining the DMD modes, the reduced-order models presented can reconstruct the wall-shear stress with relative error smaller than 0.01 % and reproduce its statistical variations for at least 1500 time units with relative error in the standard deviation or the mean smaller than 5 %. The model has also been tested to approximate the statistics of the wall-shear stress over the whole wall, showing that the regeneration of the flow structures can be reproduced by the nonlinear interaction of modes. Finally, considering the DMD modes as communities in a neural network, we examine the influence of the mode-to-mode interaction on the nonlinear flow dynamics, which explains the performance of the different models.

Pareiasaurs were globally distributed, abundant, herbivorous parareptiles with the basal-most members found only in the mid-Permian of South Africa. These basal forms form a monophyletic group and were locally abundant and became extinct at the top of the Tapinocephalus Assemblage Zone at the end of the Guadalupian. Four species of basal pareiasaurs are currently recognised: Bradysaurus baini, B. seeleyi, Embrithosaurus schwarzi and Nochelesaurus alexanderi, but they are all poorly understood and there remains historic uncertainty as to their validity. In this paper, our second contribution designed to improve understanding of the basal group, we present the first detailed cranial description and updated diagnosis for Nochelesaurus alexanderi and demonstrate that it is a distinct taxon based on one cranial autapomorphy, a large transversely wide postparietal, and a combination of cranial characters. Within the local group of mid-Permian pareiasaurs, we recognise new dental features of Nochelesaurus alexanderi: non-symmetrical marginal cusp arrangements on upper and lower teeth resulting from an extra basal mesial cusp; an incipient horizontal cingulum on lower jaw teeth, sometimes with one or two tiny medial cingular cusps; and up to ten marginal cusps. Our study demonstrates that tooth morphology and orientation, cranial ornamentation, morphology of the cheek bosses, shape of the postfrontal and postparietal, and morphology of the distal paroccipital process of the opisthotic are the most useful to identify South African mid-Permian pareiasaurs.

In this numerical and theoretical work, we study the turbulent channel flow of Newtonian and elastoviscoplastic fluids. The coherent structures in these flows are identified by means of higher order dynamic mode decomposition (HODMD), applied to a set of data non-equidistant in time, to reveal the role of the near-wall streaks and their breakdown, and the interplay between turbulent dynamics and non-Newtonian effects. HODMD identifies six different high-amplitude modes, which either describe the yielded flow or the yielded–unyielded flow interaction. The structure of the low- and high-frequency modes suggests that the interaction between high- and low-speed streamwise velocity structures is one of the mechanisms triggering the streak breakdown, dominant in Newtonian turbulence where we observe shorter near-wall streaks and a more chaotic dynamics. As the influence of elasticity and plasticity increases, the flow becomes more correlated in the streamwise direction, with long streaks disrupted for short times by localised perturbations, reflected in reduced drag. Finally, we present streamwise-periodic dynamic mode decomposition modes as a viable tool to describe the highly complex turbulent flows, and identify simple well-organised groups of travelling waves.

The Empire of Aksum was one of Africa's most influential ancient civilisations. Traditionally, most archaeological fieldwork has focused on the capital city of Aksum, but recent research at the site of Beta Samati has investigated a contemporaneous trade and religious centre located between Aksum and the Red Sea. The authors outline the discovery of the site and present important finds from the initial excavations, including an early basilica, inscriptions and a gold intaglio ring. From daily life and ritual praxis to international trade, this work illuminates the role of Beta Samati as an administrative centre and its significance within the wider Aksumite world.

We simulate the flow of two immiscible and incompressible fluids separated by an interface in a homogeneous turbulent shear flow at a shear Reynolds number equal to 15 200. The viscosity and density of the two fluids are equal, and various surface tensions and initial droplet diameters are considered in the present study. We show that the two-phase flow reaches a statistically stationary turbulent state sustained by a non-zero mean turbulent production rate due to the presence of the mean shear. Compared to single-phase flow, we find that the resulting steady-state conditions exhibit reduced Taylor-microscale Reynolds numbers owing to the presence of the dispersed phase, which acts as a sink of turbulent kinetic energy for the carrier fluid. At steady state, the mean power of surface tension is zero and the turbulent production rate is in balance with the turbulent dissipation rate, with their values being larger than in the reference single-phase case. The interface modifies the energy spectrum by introducing energy at small scales, with the difference from the single-phase case reducing as the Weber number increases. This is caused by both the number of droplets in the domain and the total surface area increasing monotonically with the Weber number. This reflects also in the droplet size distribution, which changes with the Weber number, with the peak of the distribution moving to smaller sizes as the Weber number increases. We show that the Hinze estimate for the maximum droplet size, obtained considering break-up in homogeneous isotropic turbulence, provides an excellent estimate notwithstanding the action of significant coalescence and the presence of a mean shear.

The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.

Black and White dual-purpose cattle (DSN) are kept in diverse production systems, but the same set of genetic parameters is used for official national genetic evaluations, neglecting the herd or production system characteristics. The aim of the present study was to infer genetic (co)variance components within and across defined herd descriptor groups or clusters, considering only herds keeping the local and endangered DSN breed. The study considered 3659 DSN and 2324 Holstein Friesian (HF) cows from parities one to three. The 46 herds always kept DSN cows, but in most cases, herds were ‘mixed’ herds (Mixed), including both genetic lines HF and DSN. In order to study environmental sensitivity, we had a focus on the naturally occurring negative energy balance in the early lactation period. In consequence, traits were records from the 1st official test-day after calving for milk yield (Milk-kg), somatic cell score (SCS) and fat-to-protein ratio (FPR). Genetic parameters were estimated in bivariate runs (separate runs for the three genetic lines Mixed, HF and DSN), defining the same trait from different herd groups or clusters as different traits. Additive-genetic variances and heritabilities were larger in herd groups that indicated superior herd management, implying that cow records from these herds allow a better genetic differentiation. Superior herd management included larger herds, low calving age, high herd production levels and low intra-herd somatic cell count. Herd descriptor group differences in additive-genetic variances for Milk-kg were stronger in HF than in DSN, indicating environmental sensitivity for DSN. Similar variance components and heritabilities across groups, clusters and genetic lines were found for data stratification according to geographical descriptors altitude and latitude. Considering 72 bivariate herd group runs, 29 genetic correlations were very close to 1 (mostly for Milk-kg). Somatic cell score was the trait showing the smallest genetic correlations, especially in the DSN analyses, and when stratifying herds according to genetic line compositions (rg=0.11), or according to the percentage of natural service sires (rg=0.08). For estimations based on the results of a cluster analysis considering several herd descriptors simultaneously, indications for genotype × environment interactions could be found for SCS, but genetic correlations were larger than 0.80 for Milk-kg and FPR. In conclusion, we suggest multiple-trait animal model applications in genetic evaluations, in order to select the best sires for specific herd environments or herd clusters.

Cir X-1 is a young X-ray binary exhibiting X-ray flux changes of four orders of magnitude over several decades. It has been observed many times since the launch of the Chandra X-ray Observatory with high energy transmission grating spectrometer and each time the source gave us a vastly different look. At its very lowest X-ray flux we found a single 1.7 keV blackbody spectrum with an emission radius of 0.5 km. Since the neutron star in Cir X-1 is only few thousand years old we identify this as emission from an accretion column since at this youth the neutron star is assumed to be highly magnetized. At an X-ray flux of 1.8×10−11 erg cm−2 s−1 this implies a moderate magnetic field of a few times of 1011 G. The photoionized X-ray emission line properties at this low flux are consistent with B5-type companion wind. We suggest that Cir X-1 is a very young Be-star binary.

Textual data are plagued by underreporting bias. For example, news sources often fail to report human rights violations. Cook et al. propose a multi-source estimator to gauge, and to account for, the underreporting of state repression events within human codings of news texts produced by the Agence France-Presse and Associated Press. We evaluate this estimator with Monte Carlo experiments, and then use it to compare the prevalence and seriousness of underreporting when comparable texts are machine coded and recorded in the World-Integrated Crisis Early Warning System dataset. We replicate Cook et al.’s investigation of human-coded state repression events with our machine-coded events, and validate both models against an external measure of human rights protections in Africa. We then use the Cook et al. estimator to gauge the seriousness and prevalence of underreporting in machine and human-coded event data on human rights violations in Colombia. We find in both applications that machine-coded data are as valid as human-coded data.