bluuebunny/crossref_metadata_2025 huggingface dataset:
The Spring-Mass Model and Other Reductionist Models of Bipedal Locomotion on Inclines
Authors: Selvitella Alessandro Maria , Foster Kathleen Lois
Published: June 2022

The spring-mass model is a model of locomotion aimed at giving the essential mathematical laws of the trajectory of the center of mass of an animal during bouncing gaits, such as hopping (one-dimensional) and running (two-dimensional). This reductionist mechanical system has been extensively investigated for locomotion over horizontal surfaces, whereas it has been largely neglected on other ecologically relevant surfaces, including inclines. For example, how the degree of inclination impacts the dynamics of the center of mass of the spring-mass model has not been investigated thoroughly. In this work, we derive a mathematical model which extends the spring-mass model to inclined surfaces. Among our results, we derive an approximate solution of the system, assuming a small angular sweep of the limb and a small spring compression during stance, and show that this approximation is very accurate, especially for small inclinations of the ground. Furthermore, we derive theoretical bounds on the difference between the Lagrangian and Lagrange equations of the true and approximate systems, and discuss locomotor stability questions of the approximate solutions. We test our models through a sensitivity analysis using parameters relevant to the locomotion of bipedal animals (quail, pheasant, guinea fowl, turkey, ostrich, and humans) and compare our approximate solution to the numerically derived solution of the exact system. We compare the two-dimensional spring-mass model on inclines with the one-dimensional spring-mass model to which it reduces under the limit of no horizontal velocity; we compare the two-dimensional spring-mass model on inclines with the inverted pendulum model on inclines towards which it converges in the case of high stiffness-to-mass ratio. We include comparisons with historically prevalent no-gravity approximations of these models, as well. The insights we have gleaned through all these comparisons and the ability of our approximation to replicate some of the kinematic changes observed in animals moving on different inclines (e.g., reduction in vertical oscillation of the center of mass and decreased stride length) underline the valuable and reasonable contributions that very simple, reductionist models, like the spring-mass model, can provide.
Capturing High Resolution Plant Movement in the Field
Authors: Heuschele D J , Furuta D , Smith K P , Marchetto P
Published: June 2022

Synopsis

Lodging of small grains due to environmental stresses results in yield loss, quality reduction, and difficulties with mechanical harvesting, which lead to economic consequences. New technological discoveries allow for faster and in situ measurements for determining the mechanics of loading stress and plant movement. The overall measurement of plant movement can be a very sophisticated method to mechanically test and predict the behavior of stems when exposed to wind. We investigated the inertial measurement of plants during different magnitude wind events. This type of analysis captures real time quantitative stem behavior during wind events. Using a 1.5 cm2 inertial measurement sensor attached to the upper panicle of a plant, we recorded the ranges and extremes of instantaneous linear acceleration and rotational velocity. When this technology was applied to historically known varieties of different lodging classification, the measurements were able to distinguish between cereal species and differences between movement of lodging susceptible and resistant plants without physical lodging. This type of technology could be used to improve field based lodging models and quantify movement resulting from micro changes in structural and composition of the stem, and to analyze plant movement in natural conditions with a resolution and specificity that has so far been prohibitively expensive and technologically challenging to achieve.
Integrating DNA-Based Prey Occurrence Probability into Stable Isotope Mixing Models
Authors: Hoenig Brandon D , Trevelline Brian K , Latta Steven C , Porter Brady A
Published: June 2022

Synopsis

The introduction of laboratory methods to animal dietary studies has allowed researchers to obtain results with accuracy and precision, not possible with observational techniques. For example, DNA barcoding, or the identification of prey with taxon-specific DNA sequences, allows researchers to classify digested prey tissues to the species-level, while stable isotope analysis paired with Bayesian mixing models can quantify dietary contributions by comparing a consumer's isotopic values to those derived from their prey. However, DNA-based methods are currently only able to classify, but not quantify, the taxa present in a diet sample, while stable isotope analysis can only quantify dietary taxa that are identified a priori as prey isotopic values are a result of life history traits, not phylogenetic relatedness. Recently, researchers have begun to couple these techniques in dietary studies to capitalize on the reciprocal benefits and drawbacks offered by each approach, with some even integrating DNA-based results directly into Bayesian mixing models as informative priors. As the informative priors used in these models must represent known dietary compositions (e.g., percentages of prey biomasses), researchers have scaled the DNA-based frequency of occurrence of major prey groups so that their normalized frequency of occurrence sums to 100%. Unfortunately, such an approach is problematic as priors stemming from binomial, DNA-based data do not truly reflect quantitative information about the consumer's diet and may skew the posterior distribution of prey quantities as a result. Therefore, we present a novel approach to incorporate DNA-based dietary information into Bayesian stable isotope mixing models that preserves the binomial nature of DNA-based results. This approach uses community-wide frequency of occurrence or logistic regression-based estimates of prey occurrence to dictate the probability that each prey group is included in each mixing model iteration, and, in turn, the probability that each iteration's results are included in the posterior distribution of prey composition possibilities. Here, we demonstrate the utility of this method by using it to quantify the prey composition of nestling Louisiana waterthrush (Parkesia motacilla).
Technical Note: A procedure to place urinary catheters in 1- and 6-week-old preweaned Holstein heifer calves for the in vivo evaluation of intestinal permeability
Authors: Ceja Guadalupe , Boerman Jacquelyn P , Neves Rafael C , Johnson Nicholas S , Schoonmaker Jon P , Jorgensen Matthew W , Johnson Jay S
Published: June 2022

Oral administration of indigestible markers and subsequent urine collection is a useful method to determine in vivo gastrointestinal tract (GIT) permeability in cattle for research purposes. However, urine sampling techniques often rely on total waste collection, which reduces the ability to perform more frequent sampling and obtain accurate volumes and sterile samples. An alternative is urethral catheterization, though the feasibility of this technique has not been thoroughly tested in preweaned Holstein heifer calves. The study objective was to develop a urethral catheter placement procedure in preweaned Holstein heifer calves for continuous and accurate urine collection to evaluate GIT permeability using an indigestible marker. Fifteen Holstein heifer calves had catheters placed at approximately 1 wk (8.0 ± 1.5 d) and 6 wk (40.0 ± 1.5 d) of age. During the procedure, calves were individually housed and restrained. The vulva was sterilized and then a sterile, lubricated speculum was inserted into the vagina. A sterile 0.09 cm diameter guidewire was guided into a lubricated, sterile 10 French Foley catheter. The catheter was inserted at approximately 5 through 7 cm into the urethral opening, guided into the bladder, and the catheter balloon was filled with 10 mL of water. The guidewire was removed, and urine flow confirmed correct placement before a 4-L urinary drainage bag was attached to the catheter. After catheterization (24 h), 1 L of chromium (Cr)-ethylenediaminetetraacetic acid was orally dosed to the calves. Calf health observations were made six times over a 48-h period, and any occurrence of vaginal discharge, tissue discharge in catheter, bleeding, inflammation, or abnormal urine was considered a localized reaction. The proportion of localized reactions for each age group was determined using Microsoft Excel, and the total Cr output was analyzed using PROC GLIMMIX. Localized reactions occurred for 20.0% of the 1-wk-old calves and 13.3% of the 6-wk-old calves. In the first 4 h, urine was collected every 15 min, and there were no overall Cr output differences (P = 0.38; 10.28 ± 3.21 mg Cr) when comparing 1- and 6-wk-old calves. However, 1-wk-old calves tended (P = 0.08) to have greater overall Cr output at 480 min (19.2%) and 1,440 min (41.9%) when compared with 6-wk-old calves. In summary, urinary catheterization is a viable urinary collection method for the determination of in vivo GIT permeability in preweaned Holstein heifer calves.
Human Rights Issues—A Still Neglected Managerial Area in Supply Chains? Study Results of Socially Responsible Companies from Poland
Authors: Rudnicka Agata
Published: June 2022

This article discusses human rights issues in supply chains of socially responsible companies operating in Poland. The issue of human rights in business is gaining importance both in the context of legal regulations and the approach of enterprises. Nevertheless, human rights in supply chains pose many challenges. This issue should be particularly important to companies that have decided to implement social responsibility. Two crucial research questions were asked. First, to what extent do socially responsible companies pay attention to human rights issues in supply chains? Second, if human rights issues are managed in supply chains, how is this done? The main results show that this issue is considered, but it is difficult to unequivocally assess to what extent the subject of human rights is treated strategically as an element of a business case and how far it results from the current need to be adjusted to the present societal expectations. This article outlines the general overview of the situation.
Promotion of nonalcoholic steatohepatitis by RNA N6-methyladenosine reader IGF2BP2 in mice
Authors: Zhou Bing , Luo Yunchen , Ji Nana , Mao Fei , Xiang Liping , Bian Hua , Zheng Ming-Hua , Hu Cheng , Li Yao , Lu Yan
Published: June 2022

Nonalcoholic steatohepatitis (NASH) has emerged as the major cause of end-stage liver diseases. However, an incomplete understanding of its molecular mechanisms severely dampens the development of pharmacotherapies. In the present study, through systematic screening of genome-wide mRNA expression from three mouse models of hepatic inflammation and fibrosis, we identified IGF2BP2, an N6-methyladenosine modification reader, as a key regulator that promotes NASH progression in mice. Adenovirus or adeno-associated virus-mediated overexpression of IGF2BP2 could induce liver steatosis, inflammation, and fibrosis in mice, at least in part, by increasing Tab2 mRNA stability. Besides, hepatic overexpression of IGF2BP2 mimicked gene expression profiles and molecular pathways of human NASH livers. Of potential clinical significance, IGF2BP2 expression is significantly upregulated in the livers of NASH patients. Moreover, knockdown of IGF2BP2 substantially alleviated liver injury, inflammation, and fibrosis in diet-induced NASH mice. Taken together, our findings reveal an important role of IGF2BP2 in NASH, which may provide a new therapeutic target for the treatment of NASH.
Variability and phase lags of the type-C quasi-periodic oscillation of MAXI J1348–630 with NICER
Authors: Alabarta Kevin , Méndez Mariano , García Federico , Peirano Valentina , Altamirano Diego , Zhang Liang , Karpouzas Konstantinos
Published: June 2022

We study the properties of the type-C quasi-periodic oscillation (type-C QPO) of MAXI J1348–630 during its 2019 outburst and reflare with NICER. This is the first time that the evolution of the properties of type-C QPOs is studied during an outburst reflare. We found that the properties of the type-C QPO during the reflare are similar to those of type-C QPOs observed in other black hole systems during outburst. This suggests that the physical processes responsible for type-C QPOs are the same in a reflare and in an outburst. We also found that the full width at half-maximum of a high-frequency broad-band component observed during the reflare changes significantly with energy. We studied the energy-dependent fractional rms amplitude and phase lags of the type-C QPO from 0.5 to 12 keV. We found that the fractional rms amplitude increases up to 2–3 keV and then remains approximately constant above this energy, and the lag spectra of the type-C QPO are hard. We discuss the dependence of the fractional rms amplitude and phase lags with energy in the context of Comptonization as the radiative mechanism driving the QPO rms and lag spectra.
Detection of spatial clustering in the 1000 richest SDSS DR8 redMaPPer clusters with nearest neighbor distributions
Authors: Wang Yunchong , Banerjee Arka , Abel Tom
Published: June 2022

Distances to the k-nearest-neighbor (kNN) data points from volume-filling query points are a sensitive probe of spatial clustering. Here, we present the first application of kNN summary statistics to observational clustering measurement, using the 1000 richest redMaPPer clusters (0.1 ≤ z ≤ 0.3) from the SDSS DR8 catalog. A clustering signal is defined as a difference in the cumulative distribution functions (CDFs) of kNN distances from fixed query points to the observed clusters versus a set of unclustered random points. We find that the k = 1, 2-NN CDFs of redMaPPer deviate significantly from the randoms’ across scales of 35 to 155 Mpc, which is a robust signature of clustering. In addition to kNN, we also measure the two-point correlation function for the same set of redMaPPer clusters versus random points, which shows a noisier and less significant clustering signal within the same radial scales. Quantitatively, the χ2 distribution for both the kNN-CDFs and the two-point correlation function measured on the randoms peak at χ2 ∼ 50 (null hypothesis), whereas the kNN-CDFs (χ2 ∼ 300, p = 1.54 × 10−36) pick up a much more significant clustering signal than the two-point function (χ2 ∼ 100, p = 1.16 × 10−6) when measured on redMaPPer. Finally, the measured 3NN and 4NN CDFs deviate from the predicted k = 3, 4-NN CDFs assuming an ideal Gaussian field, indicating a non-Gaussian clustering signal for redMaPPer clusters, although its origin might not be cosmological due to observational systematics. Therefore, kNN serves as a more sensitive probe of clustering complementary to the two point correlation function, providing a novel approach for constraining cosmology and galaxy–halo connection.
Proximity of exoplanets to first-order mean-motion resonances
Authors: Charalambous C , Teyssandier J , Libert A-S
Published: June 2022

Planetary formation theories and, more specifically, migration models predict that planets can be captured in mean-motion resonances (MMRs) during the disc phase. The distribution of period ratios between adjacent planets shows an accumulation in the vicinity of the resonance, which is not centred on the nominal resonance but instead presents an offset slightly exterior to it. Here, we extend on previous works by thoroughly exploring the effect of different disc and planet parameters on the resonance offset during the disc migration phase. The dynamical study is carried out for several first-order MMRs and for both low-mass Earth-like planets undergoing type-I migration and giant planets evolving under type-II migration. We find that the offset varies with time during the migration of the two-planet system along the apsidal corotation resonance family. The departure from the nominal resonance increases for higher planetary masses and stronger eccentricity damping. In the Earth to super-Earth regime, we find offset values in agreement with the observations when using a sophisticated modelling for the planet–disc interactions, where the damping time-scale depends on the eccentricity. This dependence causes a feedback that induces an increase of the resonance offsets. Regarding giant planets, the offsets of detected planet pairs are well reproduced with a classical K-factor prescription for the planet–disc interactions when the eccentricity damping rate remains low to moderate. In both regimes, eccentricities are in agreement with the observations too. As a result, planet–disc interactions provide a generic channel to generate the offsets found in the observations.
Candidate high-redshift protoclusters and lensed galaxies in the Planck list of high-z sources overlapping with Herschel-SPIRE imaging
Authors: Lammers Caleb , Hill Ryley , Lim Seunghwan , Scott Douglas , Cañameras Raoul , Dole Hervé
Published: June 2022

The Planck list of high-redshift source candidates (the PHz catalogue) contains 2151 peaks in the cosmic infrared background, unresolved by Planck’s 5 arcmin beam. Follow-up spectroscopic observations have revealed that some of these objects are $z\, {\approx }\, 2$ protoclusters and strong gravitational lenses but an unbiased survey has not yet been carried out. To this end, we have used archival Herschel-SPIRE observations to study a uniformly selected sample of 187 PHz sources. In contrast with follow-up studies that were biased towards bright, compact sources, we find that only one of our PHz sources is a bright gravitationally lensed galaxy (peak flux ${\gtrsim }\, 300$ mJy), indicating that such objects are rarer in the PHz catalogue than previously believed (<1 per cent). The majority of our PHz sources consist of many red, star-forming galaxies, demonstrating that typical PHz sources are candidate protoclusters. However, our new PHz sources are significantly less bright than found in previous studies and differ in colour, suggesting possible differences in redshift and star formation rate. None the less, 40 of our PHz sources contain ${\gt }\, 3\, \sigma$ galaxy overdensities, comparable to the fraction of ${\gt }\, 3\, \sigma$ overdensities found in earlier biased studies. We additionally use a machine-learning approach to identify less extreme (peak flux ${\sim }\, 100$ mJy) gravitationally lensed galaxies among Herschel-SPIRE observations of PHz sources, finding a total of seven candidates in our unbiased sample, and 13 amongst previous biased samples. Our new uniformly selected catalogues of ${\gt }\, 3\, \sigma$ candidate protoclusters and strong gravitational lenses provide interesting targets for follow up with higher resolution facilities, such as ALMA and JWST.
The growth and migration of massive planets under the influence of external photoevaporation
Authors: Winter Andrew J , Haworth Thomas J , Coleman Gavin A L , Nayakshin Sergei
Published: June 2022

The formation of gas giant planets must occur during the first few Myr of a star’s lifetime, when the protoplanetary disc still contains sufficient gas to be accreted on to the planetary core. The majority of protoplanetary discs are exposed to strong ultraviolet irradiation from nearby massive stars, which drives winds and depletes the mass budget for planet formation. It remains unclear to what degree external photoevaporation affects the formation of massive planets. In this work, we present a simple one dimensional model for the growth and migration of a massive planet under the influence of external FUV fields. We find that even moderate FUV fluxes $F_\mathrm{FUV}\gtrsim 100 \, G_0$ have a strong influence on planet mass and migration. By decreasing the local surface density and shutting off accretion on to the planet, external irradiation suppresses planet masses and halts migration early. The distribution of typical stellar birth environments can therefore produce an anticorrelation between semi-major axis and planet mass, which may explain the apparent decrease in planet occurrence rates at orbital periods Porb ≳ 103 d. Even moderate fluxes FFUV strongly suppress giant planet formation and inward migration for any initial semi-major axis if the stellar host mass $M_*\lesssim 0.5\, {\rm M}_\odot$, consistent with findings that massive planet occurrence is much lower around such stars. The outcomes of our prescription for external disc depletion show significant differences to the current approximation adopted in state-of-the-art population synthesis models, motivating future careful treatment of this important process.
Improved Aberth–Ehrlich root-finding algorithm and its further application for binary microlensing
Authors: Fatheddin Hossein , Sajadian Sedighe
Published: June 2022

In gravitational microlensing formalism and for modelling binary light curves, the key step is solving the binary lens equation. Currently, a combination of the Newton’s and Laguerre’s methods which was first introduced by Skowron & Gould (SG) is used while modelling binary light curves. In this paper, we first introduce a fast root-finding algorithm for univariate polynomials based on the Aberth–Ehrlich (AE) method which was first developed in 1967 as an improvement over the Newton’s method. AE algorithm has proven to be much faster than Newton’s, Laguerre’s, and Durand–Kerner methods and unlike other root-finding algorithms, it is able to produce all the roots simultaneously. After improving the basic AE algorithm and discussing its properties, we will optimize it for solving binary lens equations, which are fifth degree polynomials with complex coefficients. Our method is about 1.8–2.0 times faster than the SG algorithm. Since, for calculating magnification factors for point-like or finite source stars, it is necessary to solve the binary lens equation and find the positions of the produced images in the image plane first, this new method will improve the speed and accuracy of binary microlensing modelling.
Blandford–Znajek jets in galaxy formation simulations: exploring the diversity of outflows produced by spin-driven AGN jets in Seyfert galaxies
Authors: Talbot Rosie Y , Sijacki Debora , Bourne Martin A
Published: June 2022

Recent observations of Seyfert galaxies indicate that low-power, misaligned jets can undergo significant interaction with the gas in the galactic disc and may be able to drive large-scale, multiphase outflows. We apply our novel sub-grid model for Blandford–Znajek jets to simulations of the central regions of Seyferts, in which a black hole is embedded in a dense, sub-kpc circumnuclear disc (CND) and surrounded by a dilute circumgalactic medium. We find that the variability of the accretion flow is highly sensitive both to the jet power and to the CND thermodynamics and, ultimately, is determined by the complex interplay between jet-driven outflows and backflows. Even at moderate Eddington ratios, jets from active galactic nuclei (AGN) are able to significantly alter the thermodynamics and kinematics of CNDs and entrain up to $10{{\ \rm per\ cent}}$ of their mass in the outflow. Mass outflow rates and kinetic powers of the warm outflowing component are in agreement with recent observations for black holes with similar bolometric luminosities, with outflow velocities that are able to reach $500 \, {\rm km \, s^{-1}}$. Depending on their power and direction, jets are able to drive a wide variety of large-scale outflows, ranging from light, hot and collimated structures to highly mass-loaded, multiphase, bipolar winds. This diversity of jet-driven outflows highlights the importance of applying physically motivated models of AGN feedback to realistic galaxy formation contexts. Such simulations will play a crucial role in accurately interpreting the wealth of data that next-generation facilities such as JWST, SKA, and Athena will provide.
Probing magnetar emission mechanisms with X-ray spectropolarimetry
Authors: Caiazzo Ilaria , González-Caniulef Denis , Heyl Jeremy , Fernández Rodrigo
Published: June 2022

This year, a new era of observations of compact objects in X-ray polarization is commencing. Among the key targets for the Imaging X-ray Polarimetry Explorer mission are the magnetars 4U 0142+61 and 1RXS J170849.0-400910. Here, we present detailed predictions of the expected polarization from these sources that incorporate realistic models of emission physics at the surface (gaseous or condensed), the temperature distribution on the surface, general relativity, quantum electrodynamics, and scattering in the magnetosphere, accounting for the broad-band spectral energy distribution from below 1 keV to nearly 100 keV. We find that either atmospheres or condensed surfaces can account for the emission at a few keV. In both cases, either a small hot polar cap or scattering is required to account for the emission at 5–10 keV and, above 10 keV, scattering by a hard population of electrons can account for the rising power in the hard X-rays observed in many magnetars in quiescence. Although these different scenarios result in very similar spectral energy distributions, they generate dramatically different polarization signatures from 2 to 8 keV, which is the range of sensitivity of the Imaging X-ray Polarimetry Explorer. Observations of these sources in X-ray polarization will therefore probe the emission from magnetars in an essentially new way.
Multiwavelength observations of MAXI J1820+070 during its outburst decay and subsequent mini-outburst
Authors: Özbey Arabacı M , Kalemci E , Dinçer T , Bailyn C D , Altamirano D , Ak T
Published: June 2022

We present results from quasi-simultaneous multiwavelength observations of the Galactic black hole X-ray transient MAXI J1820+070 during the decay of the 2018 outburst and its entire subsequent mini-outburst in March 2019. We fit the X-ray spectra with phenomenological and Comptonizaton models and discuss the X-ray spectral evolution in comparison with the multiwavelength behaviour of the system. The system showed a rebrightening in UV/Optical/NIR bands 7 d after the soft-to-hard transition during the main outburst decay while it was fading in X-rays and radio. In contrast, the mini-outburst occurred 165 d after the hard state transition of the initial outburst decay and was detected in all wavelengths. For both events, the measured time-scales are consistent with those observed in other black hole systems. Contemporaneous hard X-ray/soft γ-ray observations indicate a non-thermal electron energy distribution at the beginning of the UV/Optical/NIR rebrightening, whereas a thermal distribution can fit the data during the hard mini-outburst activity. The broad-band spectral energy distributions until the rebrightening are consistent with the irradiated outer accretion disc model. However, both the SEDs produced for the peak of rebrightening and close to the peak of mini-outburst provided good fits only with an additional power law component in the UV/Optical/NIR frequency ranges, which is often interpreted with a jet origin.
Thermal conduction effects on the accretion–ejection mechanism. Outflow process investigation
Authors: Rezgui Ghassen , Marzougui Hamed , Lili Taieb , Preiner Reinhold , Ceccobello Chiara
Published: June 2022

Astrophysical jets emanating from different systems are one of the most spectacular and enigmatic phenomena pervading the Universe. These jets are typically bipolar and span hundreds of thousands of light years, some even longer than the diameter of our Milky Way. The study of the disc–jet systems is motivated by the observed correlation between ejection and accretion signatures and is still under debate. It was shown in our previous work the crucial role of thermal conduction in the dynamics of a thin viscous resistive accretion disc orbiting a central object and was provided an unprecedented wealth of discussion that has advanced our understanding of the inflow process. In this work, we expand our exploration by addressing the most outstanding basic questions concerning the launching, acceleration, and collimation processes of the jet in presence of thermal conduction. We also tackle in depth-analysis the effects of this physical ingredient on the time evolution of temperature and on mass fluxes such as inflow and outflow rates. We performed a series of 2.5-dimensional non-relativistic time-dependent numerical calculations of a disc–jet system using the PLUTO code. Our results revealed compelling evidence that thermal conduction contributes to launching a faster and more collimated jet. The mass extracted from the disc via the outflow channel is also affected by the presence of thermal conduction in the sense that the ejection efficiency is significantly improved.
Trade-Offs Predicted by Metabolic Network Structure Give Rise to Evolutionary Specialization and Phenotypic Diversification
Authors: Ekkers David M , Tusso Sergio , Moreno-Gamez Stefany , Rillo Marina C , Kuipers Oscar P , van Doorn G Sander
Published: June 2022

Mitigating trade-offs between different resource-utilization functions is key to an organism’s ecological and evolutionary success. These trade-offs often reflect metabolic constraints with a complex molecular underpinning; therefore, their consequences for evolutionary processes have remained elusive. Here, we investigate how metabolic architecture induces resource-utilization constraints and how these constraints, in turn, elicit evolutionary specialization and diversification. Guided by the metabolic network structure of the bacterium Lactococcus cremoris, we selected two carbon sources (fructose and galactose) with predicted coutilization constraints. By evolving L. cremoris on either fructose, galactose, or a mix of both sugars, we imposed selection favoring divergent metabolic specializations or coutilization of both resources, respectively. Phenotypic characterization revealed the evolution of either fructose or galactose specialists in the single-sugar treatments. In the mixed-sugar regime, we observed adaptive diversification: both specialists coexisted, and no generalist evolved. Divergence from the ancestral phenotype occurred at key pathway junctions in the central carbon metabolism. Fructose specialists evolved mutations in the fbp and pfk genes that appear to balance anabolic and catabolic carbon fluxes. Galactose specialists evolved increased expression of pgmA (the primary metabolic bottleneck of galactose metabolism) and silencing of ptnABCD (the main glucose transporter) and ldh (regulator/enzyme of downstream carbon metabolism). Overall, our study shows how metabolic network architecture and historical contingency serve to predict targets of selection and inform the functional interpretation of evolved mutations. The elucidation of the relationship between molecular constraints and phenotypic trade-offs contributes to an integrative understanding of evolutionary specialization and diversification.
Risk Factors for Hospitalization or Death Among Adults With Advanced HIV at Enrollment for Care in South Africa: A Secondary Analysis of the TB Fast Track Trial
Authors: Calderwood Claire J , Tlali Mpho , Karat Aaron S , Hoffmann Christopher J , Charalambous Salome , Johnson Suzanne , Grant Alison D , Fielding Katherine L
Published: June 2022

Background

Individuals with advanced HIV experience high mortality, especially before and during the first months of antiretroviral therapy (ART). We aimed to identify factors, measurable in routine, primary health clinic–based services, associated with the greatest risk of poor outcome.

Methods

We included all individuals enrolled in the standard-of-care arm of a cluster-randomized trial (TB Fast Track); adults attending participating health clinics with CD4 ≤150 cells/µL and no recent ART were eligible. Associations between baseline exposures and a composite outcome (hospitalization/death) over 6 months were estimated using multivariable Cox regression.

Results

Among 1515 individuals (12 clinics), 56% were female, the median age was 36 years, and the median CD4 count was 70 cells/μL. Within 6 months, 89% started ART. The overall rate of hospitalization/death was 32.5 per 100 person-years (218 outcomes/671 person-years). Lower baseline CD4 count (adjusted hazard ratio [aHR], 2.27 for <50 vs 100–150 cells/µL; 95% CI, 1.57–3.27), lower body mass index (aHR, 2.13 for BMI <17 vs ≥25 kg/m2; 95% CI, 1.31–3.45), presence of tuberculosis-related symptoms (aHR, 1.87 for 3–4 symptoms vs none; 95% CI, 1.20–2.93), detectable urine lipoarabinomannan (aHR, 1.97 for 1+ positivity vs negative; 95% CI, 1.37–2.83), and anemia (aHR, 4.42 for severe anemia [hemoglobin <8 g/dL] vs none; 95% CI, CI 2.38–8.21) were strong independent risk factors for hospitalization/death.

Conclusions

Simple measures that can be routinely assessed in primary health care in resource-limited settings identify individuals with advanced HIV at high risk of poor outcomes; these may guide targeted interventions to improve outcomes.
Plant–microbe interactions in the rhizosphere via a circular metabolic economy
Authors: Korenblum Elisa , Massalha Hassan , Aharoni Asaph
Published: June 2022

Chemical exchange often serves as the first step in plant–microbe interactions and exchanges of various signals, nutrients, and metabolites continue throughout the interaction. Here, we highlight the role of metabolite exchanges and metabolic crosstalk in the microbiome–root–shoot–environment nexus. Roots secret a diverse set of metabolites; this assortment of root exudates, including secondary metabolites such as benzoxazinoids, coumarins, flavonoids, indolic compounds, and terpenes, shapes the rhizosphere microbiome. In turn, the rhizosphere microbiome affects plant growth and defense. These inter-kingdom chemical interactions are based on a metabolic circular economy, a seemingly wasteless system in which rhizosphere members exchange (i.e. consume, reuse, and redesign) metabolites. This review also describes the recently discovered phenomenon “Systemically Induced Root Exudation of Metabolites” in which the rhizosphere microbiome governs plant metabolism by inducing systemic responses that shift the metabolic profiles of root exudates. Metabolic exchange in the rhizosphere is based on chemical gradients that form specific microhabitats for microbial colonization and we describe recently developed high-resolution methods to study chemical interactions in the rhizosphere. Finally, we propose an action plan to advance the metabolic circular economy in the rhizosphere for sustainable solutions to the cumulative degradation of soil health in agricultural lands.
Universality in anomaly flow
Authors: Hosotani Yutaka
Published: June 2022

Universality in anomaly flow by an Aharonov–Bohm phase θH is shown in the flat M4 × (S1/Z2) spacetime and in the Randall–Sundrum (RS) warped space. We analyze the SU(2) gauge theory with doublet fermions. With orbifold boundary conditions the U(1) part of the gauge symmetry remains unbroken at θH = 0 and π. Chiral anomalies smoothly vary with θH in the RS space. It is shown that the anomaly coefficients associated with this anomaly flow are expressed in terms of the values of the wave functions of the gauge fields at the UV and IR branes in the RS space. The anomaly coefficients depend on θH, the warp factor of the RS space, and the orbifold boundary conditions for fermions, but not on the bulk mass parameters of fermions.
INTERNAL EXPOSURE FROM INDOOR RADON, THORON AND THEIR PROGENY IN RESIDENCE AROUND HIGH BACKGROUND RADIATION AREA, PHANG NGA PROVINCE, THAILAND
Authors: Rattanapongs Chanis Pornnumpa , Kranrod Chutima , Jitpakdee Manit , Tokonami Shinji , Chanyotha Supitcha
Published: June 2022

A passive integrating discriminative radon-thoron monitor (Raduet) and a radon-thoron progeny monitor with a solid-state nuclear tracking detector were used for estimating indoor radon, thoron and their progeny concentrations in residential areas around the old mines of southern Thailand. Exposure to high background radiation levels from natural 238U and 232Th in the tin mine areas or active fault areas may increase the risk of lung cancer in the respiratory system when considering the health effects of the surrounding inhabitants. In this study, radon thoron and their progeny concentrations from inhalation in the study site have been assessed in dose at volunteer houses to confirm radiation effects. The annual effective doses due to inhalation of radon-thoron, radon progeny and thoron progeny using the ICRP latest dose conversion factors were estimated to be 3.0−4.6, 2.5–3.7 and 0.4–1.0 mSv, respectively, and as 5.9–9.0 mSv in total.
BVI strengthens firewall provisions in Trustee Act
Authors: McKenzie Christopher
Published: June 2022

When section 83 A of the British Virgin Islands’ Trustee Act came into effect in 2004 the jurisdiction was regarded as having the most sophisticated and well thought-out ‘firewall’ offering available, but, since then, the territory has arguably fallen behind some of its main competitors in this context. The technical amendments to section 83 A which took effect in July 2021 are aimed at improving the Territory’s firewall offering, which is considered critical in the context of the establishment of international trusts.
A porous ceramic particle with or without a preservative blend did not impair apparent digestibility of macro- and micro-nutrients of postweaned pigs
Authors: Davis Emily M , Liang Yu , Wallace Kayla P , Zimmerman Amanda J , Siebecker Matthew G , Broadway Paul Rand , Carroll Jeffrey A , Ballou Michael A
Published: June 2022

The objective of this study was to determine the effects of supplementing a commercial porous ceramic clay particle, with or without a blend of preservatives, on the performance and nutrient digestibility of weanling pigs. Fifteen weanling pigs of the Yorkshire, Landrace, and Duroc breeds were blocked by breed and randomly assigned to one of three treatments (n = 5): (1) Control, non-medicated diet with no additional feed additives (CON); (2) PowerGuard, basal diet with 0.25% of the DM consisting of a ceramic particle mixed into the pelleted feed (PG; MB Nutritional Sciences, Lubbock, TX, 79403); or (3) Power Guard + a blend of preservatives, basal diet with 0.3% of the DM consisting of the ceramic clay and preservatives mixed into the pelleted feed (PG-D). The facility was temperature controlled with an average temperature of 28.5 °C. Pigs were offered ad libitum access to feed and water and were housed individually in elevated crates. Body weights were collected upon enrollment on day 0 and at the end of the observation period on day 18. On day 15 , a 72-h total feed and fecal collection period began. Feed and fecal samples were analyzed for DM, CP, Ash, OM, ADF, NDF, zinc, copper, thiamin (vitamin B1), and retinol (vitamin A). Liver samples were collected immediately after harvest and frozen for later mineral analysis. Data were analyzed using Proc Mixed in SAS with dietary group as the main effect and block as the random effect (SAS 9.4, Cary, NC). There were no treatment differences in performance measures including final BW, ADG, or G:F (P ≥ 0.701). There were no treatment differences in diet nutrient digestibility for DM, CP, Ash, OM, ADF, or NDF (P ≥ 0.312). Additionally, there were no treatment effects on zinc, copper, or retinol digestibility (P ≥ .298); however, thiamin inclusion rate was increased for the PG-D treatment, thus leading to an increased digestibility for thiamin (P = 0.018) in the PG-D treatment. There were no treatment differences in hepatic mineral concentrations (P ≥ 0.532); however, there was a tendency for pigs fed PG-D to have increased hepatic concentrations of lead and mercury when compared with both PG and CON pigs (P ≤ 0.066). In summary, supplementation of a commercial ceramic particle with or without a blend of preservatives to weaned pigs did not affect performance or apparent nutrient digestibility.
Association of Labor Epidural Analgesia With Autism Spectrum Disorder in Children
Authors: Mikkelsen A. , Greiber  , Scheller N. , Lidegaard O.
Published: June 2022

(JAMA. 2021;326:1170–1177)

Epidural analgesia is an effective and commonly used modality of labor analgesia. More than 70% of women in the United States utilize neuraxial analgesia. A recent cohort study reported an association with autism spectrum disorder (ASD) in children born after epidural analgesia compared to unexposed children. Five major obstetric and anesthesiology societies issued statements stating the study did not provide evidence of causal inference and described limitations of the study including residual confounding. They recommended further high-quality studies be conducted to further evaluate the association. This study aimed to determine the relationship between epidural labor analgesia and ASD using public Danish databases.
Association of Epidural Analgesia During L&D With Autism Spectrum Disorder in Offspring
Authors: Hanley G.E. , Bickford C. , Ip A. , Lanphear N. , Lanphear B. , Weikum W. , Zwaigenbaum L. , Oberlander T.F.
Published: June 2022

(JAMA. 2021;326:1178–1185)

Although epidural analgesia is a common and safe modality for pain relief during labor and delivery, few studies have examined long-term outcomes. Since 2000 the diagnosis of Autism Spectrum Disorder (ASD) in children has increased from 1 in 150 to 1 in 54 in 2016 in the United States. Inconsistent and conflicting studies have suggested there may be a relationship between epidural analgesia and a later diagnosis of ASD. Considering epidural analgesia use is reported at 57% in Canada and higher than 70% in the United States, millions of newborns in both countries could be impacted. The aim of this population-based study of British Columbia, Canada evaluated the association between ASD in offspring and maternal epidural analgesia use during delivery.
Labor Epidural Analgesia and Autism Spectrum Disorder: Is There an Association?
Authors: Wong C. , Stevens H.
Published: June 2022

(JAMA. 2021;326:1155–1157)

Autism spectrum disorder (ASD) is a disorder with known genetic and environmental factors. These factors include birth complications, maternal preeclampsia, obesity, diabetes, prenatal exposure to anticonvulsants, prenatal exposure to asthma medications, and prematurity. Most researchers conclude that an increase in the diagnosis of ASD throughout the years can be attributed to the increased awareness of ASD, but some question whether factors causing or contributing to ASD are going undetected.
Intravenous Oxytocin Dosing Regimens for Postpartum Hemorrhage Prevention Following Cesarean Delivery: A Systematic Review and Meta-Analysis
Authors: Phung L.C. , Farrington E.K. , Connolly M. , Wilson A.N. , Carvalho B. , Homer C.S.E. , Vogel J.P.
Published: June 2022

(Am J Obstet Gynecol. 2021;225:250.e1–250.e38. [Epub May 4, 2021])

Postpartum hemorrhage (PPH) is a leading cause of maternal mortality. A common cause of PPH is uterine atony. To decrease the nearly 20% of 295,000 worldwide maternal deaths from PPH, there has been an increase in the use of uterotonics for all women during delivery. In 2018 the World Health Organization (WHO) recommended 10 IU of oxytocin to be administered to all women for both vaginal and cesarean deliveries (CD) to improve uterine atony and prevent PPH. There is insufficient evidence that 10 IU was an optimal amount for both types of delivery and the dose was based on insufficient evidence from an outdated Cochrane systematic review. The purpose of this review was to analyze the dosing regimens of IV oxytocin used for CD and to determine if any regimens are superior to others.
Preeclampsia and Long-term Health Outcomes for Mother and Infant: An Umbrella Review
Authors: Pittara T. , Vyrides A. , Lamnisos D. , Giannakou K.
Published: June 2022

(BJOG. 2021;128:1421–1430. [Epub March 23, 2021])

Preeclampsia during pregnancy is a risk factor for multiple long-term health outcomes in both mother and infant. As the most prevalent hypertensive condition in pregnancy, it affects 2% to 8% of all pregnancies and is a leading cause of maternal and neonatal morbidity and mortality. Occurring after the 20th week of gestation, preeclampsia involves multisystem organ dysfunction, and can lead to many short-term acute maternal complications and adverse neonatal outcomes including death, usually secondary to preterm delivery. In addition to the close-range impacts, mounting evidence suggests increased risk of future cardiovascular, metabolic, and renal disease in the mother. Long-range reports in neonates indicate risk for altered cognitive abilities, psychiatric disorders, and mood and anxiety disturbances. Most research studies are observational and are summarized by outcome through systematic review and meta-analysis, and thus are subject to the bias of inflated estimates of association. This umbrella review is offered to contextualize quality and strength of evidence across all long-term outcomes in mother and infant and identify the associations with the strongest epidemiological evidence.
Black-White Disparities in Maternal In-Hospital Mortality According to Teaching and Black-serving Hospital Status
Authors: Burris H.H. , Passarella M. , Handley S.C. , Srinivas S.K. , Lorch S.A.
Published: June 2022

(Am J Obstet Gynecol. 2021;225:83.e1–9)

From 1987 to 2018, the maternal mortality rate (MMR) in the United States rose from 7.2 per 100,000 live births to 17.4. Compared with white patients, Black patients have significantly higher maternal mortality rate (14.9 vs. 37.3 per 100,000 live births). There are multiple factors contributing to this disparity. Approximately 90% of preventable maternal mortality may be due to provider factors, and therefore it is important to identify provider factors that contribute to the higher MMR among Black patients. The authors hypothesized that racial disparities in in-hospital MMR would differ between teaching and nonteaching hospitals. Further they hypothesized that the disparity would be larger in hospitals that care for a lower proportion of Black patients.
Population Risk Factors for Nulliparous, Term, Singleton, Vertex Cesarean Birth: A National Cross-sectional Study
Authors: Andrikopoulou M. , Wen T. , Sheen J.J. , Krenitsky N. , Baptiste C.D. , Goffman D. , Staniczenko A.P. , D'Alton M.E. , Friedman A.M.
Published: June 2022

(BJOG. 2021;128:1456–1463. [Epub April 6, 2021])

Analysis of nulliparous, term, singleton, vertex (NTSV) cesarean births remains an important measure for quality of care. Hospital-level NTSV-cesarean statistics are endorsed by many quality leadership organizations as a metric of interest. Relevant to interpreting NTSV hospital-level cesarean rate is the degree to which patient factors modify risk, including obesity, maternal age, and pregestational diabetes. The case mix at hospitals may contribute to differentially distributed risk factors that increase the likelihood of NTSV cesarean delivery (CD). This cross-sectional study investigated whether medical, obstetric, and demographic factors were associated with risk for NTSV CD.
Association Between Iatrogenic Delivery for Suspected Fetal Growth Restriction and Childhood School Outcomes
Authors: Selvaratnam R.J. , Wallace E.M. , Wolfe R. , Anderson P.J. , Davey M.-A.
Published: June 2022

(JAMA. 2021;326:145–153)

Undetected fetal growth restriction (FGR) is associated with a late pregnancy stillbirth rate of 16.4 per 1000, but when detected and managed, the rate of stillbirth drops to 0.8 per 1000. Clinicians face difficult decisions in managing pregnancies affected by FGR, as prematurity is associated with a host of poor neonatal and childhood outcomes. In addition, fetuses are commonly falsely suspected of having FGR. This study investigated the childhood school outcomes for children born via iatrogenic delivery for suspected FGR.