bluuebunny/crossref_metadata_2025 huggingface dataset:
Convergence and molecular evolution of floral fragrance after independent transitions to self–fertilization
Authors: Wozniak Natalia , Sartori Kevin , Kappel Christian , Zhao Lihua , Erban Alexander , Fehrle Ines , Jantzen Friederike , Orsucci Marion , Rosa Stefanie , Lenhard Michael , Kopka Joachim , Sicard Adrien
Published: October 2022

The study of the independent evolution of similar characters can highlight important ecological and genetic factors that drive phenotypic evolution. The transition from reproduction by outcrossing to self-fertilization has occurred frequently throughout plant evolution. A common trend in this transition is the reduction of flower features in the selfing lineages, including display size, flower signals and pollinators’ rewards. These changes are believed to evolve because resources invested in building attractive flowers are reallocated to other fitness functions as the pressures to attract pollinators decrease. We investigated the similarities in the evolution of flower fragrance after independent transitions to self-fertilization in Capsella. We identified a large number of compounds that are similarly changed in different selfer lineages, such that the composition of the flower scent can predict the mating system in this genus. We further demonstrate that the emission of some of these compounds convergently evolved based on mutations in different genes. In one of the Capsella selfing lineages, the loss of β-ocimene emission was caused by a mutation altering subcellular localization of the ortholog of TERPENE SYNTHASE 2 without apparent effects on its biosynthetic activity. This mutation appears to have been selected at the early stage of this selfing lineage establishment through the capture of a variant segregating in the ancestral outcrossing population. The large extent of convergence in the independent evolution of flower scent, together with the evolutionary history and molecular consequences of a causal mutation, suggest that the emission of specific volatiles has important fitness consequences in self-fertilizing plants without obvious energetic benefits.
Increased sampling and intra-complex homologies favor vertical over horizontal inheritance of the Dam1 complex
Authors: van Rooijen Laura E. , Tromer Eelco C. , van Hooff Jolien J. E. , Kops Geert J. P. L. , Snel Berend
Published: October 2022

Kinetochores connect chromosomes to spindle microtubules to ensure their correct segregation during cell division. Kinetochores of human and yeast are largely homologous, their ability to track depolymerizing microtubules however is carried out by the non-homologous complexes Ska1-C and Dam1-C, respectively. We previously reported the unique anti-correlating phylogenetic profiles of Dam1-C and Ska-C found amongst a wide variety of eukaryotes. Based on these profiles and the limited presence of Dam1-C, we speculated that horizontal gene transfer (HGT) could have played a role in the evolutionary history of Dam1-C.

Here, we present expanded analyses of Dam1-c evolution, using additional genome as well as transcriptome sequences and recently acquired 3D structure data. This analysis revealed a wider and more complete presence of Dam1-C in Cryptista, Rhizaria, Ichthyosporea, CRuMs, and Colponemidia. The fungal Dam1-C cryo-EM structure supports earlier hypothesized intra-complex homologies, which enables the reconstruction of rooted and unrooted phylogenies. The rooted tree of concatenated Dam1-C subunits is statistically consistent with the species tree of eukaryotes, suggesting that Dam1-C is ancient, and that the present-day phylogenetic distribution is best explained by multiple, independent losses and no HGT was involved. Furthermore, we investigated the ancient origin of Dam1-C via profile-profile searches. Homology among eight out of the ten Dam1-C subunits suggested that the complex largely evolved from a single multimerizing subunit that diversified into an octameric core via stepwise duplication and sub-functionalization of the subunits before the origin of the Last Common Ancestor.

Significance

The Dam1 complex has a crucial role in cell division yet its distribution across species is very patchy. To resolve the evolutionary origin of this peculiar distribution, we used the recently acquired 3D structure to obtain a rooted phylogeny. This study makes an important step in discovering the evolutionary history of the Dam1 complex, by determining that Dam1-C was part of the Last eukaryotic Common Ancestor and arose via stepwise duplications during the transition from prokaryotes to eukaryotes.
A galanin-positive population of lumbar spinal cord neurons modulates sexual arousal and copulatory behavior
Authors: Lenschow Constanze , Mendes Ana Rita P. , Ferreira Liliana , Lacoste Bertrand , Marques Hugo , Quilgars Camille , Bertrand Sandrine S. , Lima Susana Q.
Published: October 2022

During sex, male arousal increases to the ejaculatory threshold, allowing genital sensory input to trigger ejaculation. While copulation and sexual arousal are thought to be centrally regulated by the brain, ejaculation is considered a reflex controlled by a spinal circuit. In this framework, the spinal cord is assumed to be strongly inhibited by descending input from the brain until the ejaculatory threshold, playing no role in the regulation of copulatory behavior. However, this remains untested. Here, we mapped the spinal circuit controlling the bulbospongiosus muscle, which is involved in sperm expulsion in mice. Our findings reveal that bulbospongiosus muscle-motor neurons receive input from galanin-expressing interneurons. This galanin-positive population receives genital input and, while its stimulation leads to bulbospongiosus muscle activity, the evoked muscle-potentials are dependent on spinalization, the male’s internal state and decrease with repeated stimulation. Moreover, ablation of galanin neurons affected the latency to ejaculate and altered the copulatory pattern. These results suggest an unexpected role of spinal circuits in the control of copulation and arousal, in addition to its established role in ejaculation.
Evaluation of K-Ras4B dimer interfaces and the role of Raf effectors
Authors: Chatzigoulas Alexios , Andreadelis Ioannis , Doerr Stefan , Lamprakis Christos , Theodoropoulou Anastasia , Manchester John , Velez-Vega Camilo , Duca Jose , Cournia Zoe
Published: October 2022

K-Ras4B is one the most frequently mutated proteins in cancer, yet mechanistic details of its activation such as its homodimerization on the membrane remain elusive. The structural determinants of K-Ras4B homodimerization have been debated with different conformations being proposed in the literature. Here, we perform microsecond all-atom Molecular Dynamics (MD) simulations on the K-Ras4B monomer in solution, the K-Ras4B monomer on the membrane, and two experimentally-based K-Ras4B dimer models of the α4-α5 interface to investigate the stability of these structures bound to GTP on a model cell membrane. We then evaluate the complexes for their propensity to form stable dimers on the plasma membrane in the presence and absence of Raf[RBD–CRD] effectors. We find that Raf[RBD-CRD] effectors enhance dimer stability, suggesting that the presence of effectors is necessary for K-Ras4B dimers stabilization on the cell membrane. Moreover, we observe, for the first time, a dynamic water channel at the K-Ras4B dimer interface, and identify putative allosteric connections in the K-Ras4B dimer interface. To discover novel K-Ras4B interfaces, we perform coarse-grained MD simulations in two dissociated K-Ras4B monomers on the membrane, which reveal that the dominant dimer interface is the α4-α5 interface. Finally, a druggability analysis is performed in the different K-Ras4B structures in the monomeric states. Strikingly, all known binding pockets of K-Ras4B are identified only in the structure that is membrane-bound, but not in the solution structure. Based on these results, we propose that modulating the protein-membrane interactions can be an alternative strategy for inhibiting K-Ras4B signaling.
The maximum solubility product marks the threshold for condensation of multivalent biomolecules
Authors: Chattaraj Aniruddha , Loew Leslie M.
Published: October 2022

Clustering of weakly interacting multivalent biomolecules underlies the formation of membraneless compartments known as condensates. As opposed to single component (homotypic) systems, the concentration dependence of multi-component (heterotypic) condensate formation is not well understood. We previously proposed the solubility product (SP), the product of monomer concentrations in the dilute phase, as a tool for understanding the concentration dependence of multi-component systems. In the current study, we further explore the limits of the SP concept using spatial Langevin dynamics and rule-based stochastic simulations. We show, for a variety of idealized molecular structures, how the maximum SP coincides with the onset of the phase transition, i.e., the formation of large clusters. We reveal the importance of intra-cluster binding in steering the free and cluster phase molecular distributions. We also show how structural features of biomolecules shape the solubility product profiles. The interplay of flexibility, length and steric hindrance of linker regions controls the phase transition threshold. Remarkably, when solubility products are normalized to non-dimensional variables and plotted against the concentration scaled to the threshold for phase transition, the curves all coincide independent of the structural features of the binding partners. Similar coincidence is observed for the normalized clustering vs. concentration plots. Overall, the principles derived from these systematic models will help guide and interpret in vitro and in vivo experiments on the biophysics of biomolecular condensates.

Significance Statement

Biomolecular condensates are macroscopic intracellular structures that are composed of weakly interacting macromolecules. Because their composition can be complex, there are no simple rules for how condensates form as a function of the concentrations of their individual components. In this work, we show how the solubility product (SP), the product of monomer concentrations in the dilute phase, might serve as a tool for predicting the concentration dependence for condensation of multi-component systems. Specifically, Langevin dynamics simulations of the clustering of a series of multivalent binding partners reveals how the maximum SP is always attained at the same concentration as the appearance of large clusters. Experimental application of the SP concept should help rationalize the cellular formation of biomolecular condensates.
Generating fast-twitch myotubes in vitro using an optogenetic-based, quantitative contractility assay
Authors: Hennig Katharina , Hardman David , Barata David , Martins Inês , Bernabeu Miguel O. , Gomes Edgar R. , Roman William
Published: October 2022

The composition of fiber types within skeletal muscle impacts the tissue’s physiological characteristics and susceptibility to disease and ageing. In vitro systems should therefore account for fiber type composition when modelling muscle conditions. To induce fiber specification in vitro, we designed a quantitative contractility assay based on optogenetics and particle image velocimetry. We submitted cultured myotubes to long-term intermittent light stimulation patterns and characterized their structural and functional adaptations. After several days of in vitro exercise, myotubes contract faster and are more resistant to fatigue. The enhanced contractile functionality was accompanied by advanced maturation such as increased width and upregulation of neuron receptor genes. We observed an upregulation in the expression of distinct myosin heavy chain isoforms (namely, neonatal-Myh8 and fast-Myh), which induced a shift towards a fast fiber phenotype. This long-term in vitro exercise strategy can be used to study fiber specification and refine muscle disease modelling.
Reduction of embryonic E93 expression as a key factor for the evolution of insect metamorphosis
Authors: Fernandez-Nicolas Ana , Machaj Gabriela , Ventos-Alfonso Alba , Pagone Viviana , Minemura Toshinori , Ohde Takahiro , Daimon Takaaki , Ylla Guillem , Belles Xavier
Published: October 2022

The early embryo of the cockroach Blattella germanica exhibits high E93 expression. In general, E93 triggers adult morphogenesis during postembryonic development, but in the cockroach E93 is also crucial in early embryogenesis. Moreover, the embryonic levels of E93 expression are high in hemimetabolan insects, while in holometabolans they are very low. They are also low in Thysanoptera and in Hemiptera Sternorrhyncha with postembryonic quiescent stages, as well as in Odonata, the nymph of which is very different from the adult. In ametabolans, such as the Zygentoma Thermobia domestica, E93 expression levels are very high in the early embryo, whereas during postembryonic development they are medium and relatively constant. Given that embryogenesis of hemimetabolans yields an adultiform nymph, we speculate that E93 plays some sort of adult triggering role in the embryo of these species. We conjecture that the reduction of E93 transcript levels in the embryo has been instrumental in the evolution of insect metamorphosis. The suppression of E93 expression during the nymphal period, and its concentration in the preadult stage, is consubstantial with the emergence of hemimetaboly. As such, attenuation of E93 expression in the embryo could have resulted in a larval genetic program and the emergence of holometaboly. Independent decreases of E93 expression in the embryo of Odonata, Thysanoptera, and different groups of Hemiptera Sternorrhyncha would have allowed the development of modified juvenile stages adapted to specific ecophysiological conditions.
Chemical Imaging Reveals Diverse Functions of Tricarboxylic Acid Metabolites in Root Growth and Development
Authors: Zhang Tao , Noll Sarah E. , Peng Jesus T. , Klair Amman , Tripka Abigail , Stutzman Nathan , Cheng Casey , Zare Richard N. , Dickinson Alexandra J.
Published: October 2022

Understanding how plants grow is critical for agriculture and fundamental for illuminating principles of multicellular development 1. Here, we apply chemical mapping of the developing maize root using desorption electrospray ionization mass spectrometry imaging (DESI-MSI) 2. This technique reveals a range of small molecule distribution patterns across the gradient of stem cell differentiation in the root. To understand the developmental logic of these patterns, we examined tricarboxylic acid (TCA) cycle metabolites. In both Arabidopsis and maize, TCA metabolites are enriched in developmentally opposing regions, suggesting that stem-cell specific TCA metabolite localization may be conserved in evolutionarily divergent species. We find that these metabolites, particularly succinate, aconitate, citrate, and α-ketoglutarate, control root development in diverse and distinct ways. Critically, the effects of metabolites on stem cell behavior can be independent of their canonical role in ATP production. These results present new insights into development and suggest practical means for controlling plant growth.
Transcriptomic remodeling of the retina in a Zebrafish model of Retinitis Pigmentosa
Authors: Santhanam Abirami , Shihabeddin Eyad , Wei Haichao , Wu Jiaqian , O’Brien John
Published: October 2022

Inherited retinal degenerative diseases such as Retinitis Pigmentosa (RP) result in progressive loss of photoreceptors until an individual is completely blind. A hallmark of these diseases is progressive structural and functional remodeling of the remaining retinal neurons as rod photoreceptors are lost. While many studies focus on regenerative or bionic therapies to restore vision, extensive remodeling of retinal cell types throughout the course of retinal degenerative diseases stands as a barrier for successful implementation of these strategies. As a window onto the molecular basis of remodeling, we have performed a comparative analysis of single-cell transcriptome data from adult Zebrafish retina of wild-type and a P23H mutant rhodopsin model of RP. In addition to providing a benchmark atlas of retinal cell type transcriptomes in the wild-type adult Zebrafish retina, we find transcriptional changes in essentially all retinal cell types in the P23H model. Increased oxidative stress is evident not only in the rods but also in cones, retinal pigmented epithelium (RPE) and to a lesser extent in amacrine and bipolar cells. Metabolic changes increasing oxidative metabolism and glycolysis are found in rods and cones, while evidence of increased activity of the mitochondrial electron transport chain is found in retinal ganglion cells (RGCs). Evidence of synaptic remodeling is found throughout the retina, with changes to increase synaptic transmission in photoreceptors and bipolar cells, increased ionotropic glutamate receptors in amacrine and ganglion cells, and dendritic and axon remodeling throughout. Surprisingly, RPE, cones and bipolar cells in the P23H retinas also have increased expression of genes involved in circadian rhythm regulation. While this model system undergoes continuous regeneration, ongoing remodeling impacts the entire retina. This comprehensive transcriptomic analysis provides a molecular road map to understand how the retina remodels in the context of chronic retinal degeneration with ongoing regeneration.
Pre-Steady-State Kinetic Characterization of an Antibiotic-Resistant Mutation of Staphylococcus aureus DNA Polymerase PolC
Authors: Nelson-Rigg Rachel , Fagan Sean P. , Jaremko William J. , Pata Janice D.
Published: October 2022

The emergence and spread of antibiotic resistance in bacterial pathogens are serious and ongoing threats to public health. Since chromosome replication is essential to cell growth and pathogenesis, the essential DNA polymerases in bacteria have long been targets of antimicrobial development, although none have yet advanced to the market. Here we use transient-state kinetic methods to characterize the inhibition of the PolC replicative DNA polymerase from Staphylococcus aureus by ME-EMAU, a member of the 6-anilinouracil compounds that specifically target PolC enzymes, which are found in low-GC content Gram-positive bacteria. We find that ME-EMAU binds to S. aureus PolC with a dissociation constant of 14 nM, more than 200-fold tighter than the previously reported inhibition constant, which was determined using steady-state kinetic methods. This tight binding is driven by a very slow off rate, 0.006 s-1. We also characterized the kinetics of nucleotide incorporation by PolC containing a mutation of phenylalanine 1261 to leucine (F1261L). The F1261L mutation decreases ME-EMAU binding affinity by at least 3500-fold, but also decreases the maximal rate of nucleotide incorporation by 11.5-fold. This suggests that bacteria acquiring this mutation would be likely to replicate slowly and be unable to out-compete wild-type strains in the absence of inhibitor, reducing the likelihood of the resistant bacteria propagating and spreading resistance.
Exploring the meaningfulness of integrated reporting: a framing perspective
Authors: Okwuosa Innocent , Atkins Jill
Published: October 2022

Purpose

The purpose of the study is to explain why there is a conflict in the meaningfulness of integrated reporting (IR) between International Integrated Reporting Council (IIRC) and analysts and institutional investors using framing theory and suggest a way forward for a meaningful IR to analysts and institutional investors.

Design/methodology/approach

The study used qualitative research design in which data was collected from IIRC's document and 21 semi-structured interviews of analysts and fund managers conducted between 2014 and 2015 after the introduction of IIRC framework. This period coincided with prior studies that provide conflicting evidence over the meaningfulness of IR between IIRC and analysts and fund managers.

Findings

The findings show that the IIRC from inception uses a preparer-centred frame where it predominantly interprets IR as meaningful from the perspective of preparers of information under ideal conditions, and as such also meaningful to fund managers and analysts. On the other hand, the fund managers and analysts from the onset use a user-centred frame where they interpret IR as not meaningful from their perspective as users of the information under pragmatic conditions. The context making it difficult to reconcile the differentiated frames are the timeframe; absence of trust relationship and balance in reporting.

Research limitations/implications

The study is limited by its qualitative nature meaning that generalisation of findings may not apply. Its data is also limited to IIRC IR Framework, analysts and fund managers as opposed to wider stakeholders.

Practical implications

The practical implication of the findings suggests that if IR is to be made meaningful to analysts and fund managers, the promoters must reconcile the differentiations in frames employed by both the IIRC, analysts and institutional investors. Without this reconciliation IR may not serve the information needs of the intended primary users.

Originality/value

The study uses framing theory to show that time frame, emotional connectedness and data financialisation are attributes that make IR to be considered meaningful to analysts and fund managers. In addition, it provides insight into how the use of organisational and market context influences the framing of the meaningfulness of IR.
Passengers' service perceptions emerging from user-generated content during the pandemic: the case of leading low-cost carriers
Authors: Saydam Mehmet Bahri , Olorunsola Victor Oluwafemi , Rezapouraghdam Hamed
Published: October 2022

Purpose

Although a vast amount of research has been started to gauge customer satisfaction using surveys, the influence of COVID-19 on passengers' satisfaction has not received enough attention. Hence, the primary purpose of this research is to determine the dominant themes that emerged from airline travelers' online reviews and to determine attributes that are pertinent to the satisfaction of passengers flying with low-cost carriers (LCC) during the COVID-19 outbreak. In addition, this study investigates whether the salient themes of passengers' overall experiences vary by traveler origin, which may give more insight into airline sector market segmentation.

Design/methodology/approach

Leximancer software was used to construct concepts from words, followed by themes in the data analysis.

Findings

The analyses revealed eight themes in descriptions of “travel experiences” for airline passengers. These are “flights,” “staff,” “service,” “hygiene,” “cancellations,” “legroom,” “COVID-19” and “test”. Negative reviews associated with “cancellations,” “refund,” “waiting” and “baggage” (handling) concepts.

Originality/value

The findings provide important information about airline passengers' overall experiences. Limited studies have comprehensively considered various satisfaction categories of airline travelers using online reviews.
Malignant melanoma treatment using brachytherapy: Two case reports and 15 case series
Authors: Ishiguro Akihiro , Ogata Dai , Okuma Kae , Kashihara Tairo , Murakami Naoya , Hiki Kojiro , Yamakawa Kohei , Jinnai Shunichi , Takahashi Akira , Namikawa Kenjiro , Igaki Hiroshi , Yamazaki Naoya
Published: October 2022

Malignant melanoma (MM) is usually resistant to radiotherapy. Brachytherapy may be an option in patients with bleeding or pain, and those in whom surgery is difficult. Brachytherapy has few side effects and can be used in combination with external beam radiotherapy or chemotherapy. We summarize the demographic and clinical characteristics of 15 patients who received brachytherapy for MM at our hospital and describe two of these representative cases. Patient 1 had an approximately 10‐mm, dark‐red nodule near the external urethral meatus. Excision was not performed to preserve urethral function. A gradual improvement was observed after 48 Gy of remote afterloading system (RALS) brachytherapy and nivolumab therapy. Patient 2 had a 38‐mm, black tumor on the vagina. Post‐resection, RALS brachytherapy was administered to treat the residual black macule and a lesion quickly disappeared. In all 15 cases, nine patients received radiotherapy for local control and six patients received palliative radiotherapy to reduce symptoms such as bleeding and pain. The irradiation site was the vagina in six patients, lymph node metastasis in five, head and neck in two, skin or subcutaneous metastases in two, and the anus in one. Treatment effect for local control and palliative care was 75% and 83% of patients, respectively. In particular, disappearance of the tumor or disappearance of symptoms was observed in half of the cases of brachytherapy to the vagina. On the other hand, brachytherapy was not very effective for lymph node metastases. Immediately after radiotherapy, eight (53%) patients experienced dermatitis or mucositis. Due to the histological and structural characteristics of mucosal melanoma of the luminal organs, brachytherapy may be an effective therapy. Hence, widespread use of brachytherapy with an appropriate irradiation technique aiming for local control and palliative care in case of unresectable MM should be considered.
Increasing prevalence of severe fires change the structure of arthropod communities: Evidence from a meta‐analysis
Authors: Bieber Blyssalyn V. , Vyas Dhaval K. , Koltz Amanda M. , Burkle Laura A. , Bey Kiaryce S. , Guzinski Claire , Murphy Shannon M. , Vidal Mayra C.
Published: October 2022

Animal ecology and evolution are shaped by environmental perturbations, which are undergoing unprecedented alterations due to climate change. Fire is one such perturbation that causes significant disruption by causing mortality and altering habitats and resources for animals. Fire regimes are changing on a global scale, but the effects of these changes on animal communities are poorly understood. Arthropods are one of the most ubiquitous and diverse animal taxa on the planet and their populations are sensitive to environmental change. Given their wide‐ranging impacts on ecosystem functioning, a better understanding of arthropod responses to changing fire regimes is critical and may also provide more general insights into how other groups might respond to fire.

Here, we provide a comprehensive meta‐analytical assessment of how fire influences the arthropod community across habitats and functional groups. Using data from 130 peer‐reviewed papers across the globe, we tested how a variety of fire characteristics, including management regime, severity and time‐since‐fire affect arthropod populations and communities across habitats.

Our results show that arthropod communities display substantial variation in response to fire and that community‐level responses are most likely to be detected within the first year. Responses also vary depending on fire characteristics and habitat. Specifically, while community metrics such as diversity were increased by low severity fires, they were reduced by high severity fires. Likewise, evenness increased after prescribed burns but was reduced after wildfire. Measures of arthropod community structure decreased following fires in deserts and forests.

Across the entire arthropod community, fire also had variable effects on community diversity. Fire tended to have a negative effect size on arthropods across life stages, but responses did vary among groups. Nearly all functional groups exhibited a negative response to fire with the exception of herbivores, for which abundance, diversity and richness increased after fire.

Our results suggest that the increasing prevalence of high‐severity wildfires are changing the structure of arthropod communities. Given their ubiquitous presence and diverse roles in terrestrial ecosystems, these community changes are likely to affect ecosystem functioning in various ways, including through increased herbivory.

Read the free Plain Language Summary for this article on the Journal blog.
Forest disturbance and growth processes are reflected in the geographical distribution of large canopy gaps across the Brazilian Amazon
Authors: Reis Cristiano Rodrigues , Jackson Toby D. , Gorgens Eric Bastos , Dalagnol Ricardo , Jucker Tommaso , Nunes Matheus Henrique , Ometto Jean Pierre , Aragão Luiz E. O. C. , Rodriguez Luiz Carlos Estraviz , Coomes David A.
Published: October 2022

Canopy gaps are openings in the forest canopy resulting from branch fall and tree mortality events. The geographical distribution of large canopy gaps may reflect underlying variation in mortality and growth processes. However, a lack of data at the appropriate scale has limited our ability to study this relationship until now.

We detected canopy gaps using a unique LiDAR dataset consisting of 650 transects randomly distributed across 2500 km2 of the Brazilian Amazon. We characterized the size distribution of canopy gaps using a power law and we explore the variation in the exponent, α. We evaluated how the α varies across the Amazon, in response to disturbance by humans and natural environmental processes that influence tree mortality rates.

We observed that South‐eastern forests contained a higher proportion of large gaps than North‐western, which is consistent with recent work showing greater tree mortality rates in the Southeast than the Northwest. Regions characterized by strong wind gust speeds, frequent lightning and greater water shortage also had a high proportion of large gaps, indicating that geographical variation in α is a reflection of underlying disturbance processes. Forests on fertile soils were also found to contain a high proportion of large gaps, in part because trees grow tall on these sites and create large gaps when they fall; thus, canopy gap analysis picked up differences in growth as well as mortality processes. Finally, we found that human‐modified forests had a higher proportion of large gaps than intact forests, as we would expect given that these forests have been disturbed.

Synthesis. The proportion of large gaps in the forest canopy varied substantially over the Brazilian Amazon. We have shown that the trends can be explained by geographical variation in disturbance and growth. The frequency of extreme weather events is predicted to increase under climate change, and changes could lead to greater forest disturbance, which should be detectable as an increased proportion of large gaps in intact forests.
Linking animal behaviour and tree recruitment: Caching decisions by a scatter‐hoarder corvid determine seed fate in a Mediterranean agroforestry system
Authors: Molina‐Morales Mercedes , Leverkus Alexandro B. , Albaladejo‐Robles Gonzalo , Martínez‐Baroja Loreto , Pérez‐Camacho Lorenzo , Villar‐Salvador Pedro , Rebollo Salvador , Rey‐Benayas José María , Castro Jorge
Published: October 2022

Seed dispersal by scatter‐hoarder corvids is key for the establishment of important tree species from the Holarctic region such as the walnut (Juglans regia). However, the factors that drive animal decisions to cache seeds in specific locations and the consequences of these decisions on seed fate are poorly understood.

We experimentally created four distinct, replicated habitat types in a Mediterranean agricultural landscape where the Eurasian magpie (Pica pica) is a common scatter hoarder: soft bare soil; compacted bare soil; compacted soil with a dense herbaceous cover; and soft linear bare soil made up of the irrigation furrows that separated the rest of the treatments. We also experimentally placed visual landmarks (stones, sticks and bunches of dry plants) to test if magpies use them to place seed caches. Walnut dispersal from feeders to the habitats was monitored by radiotracking and camera traps.

A sowing experiment simulating natural caches tested the effect of caching type on seed germination and seedling emergence. Seed mass was controlled for the dispersal and sowing experiments.

Magpies selected the two habitats with soft soil, and avoided the one with compacted soil, to cache nuts. Seed mass did not affect dispersal distance, germination or emergence; however, heavier seeds were cached more often under litter and in the habitat with herbaceous cover, whereas lighter seeds were more often buried in the soft bare soil habitat. Seed burial under soil or litter determined seed fate, as there was virtually no emergence from unburied nuts. There was no evidence of any effect of the visual landmarks.

Synthesis. The consequences of seed caching for seedling early establishment are driven by a fine decision‐making process of the disperser. Magpies seemed to ponder the characteristics of the habitat and the seed itself to determine where and how to cache each nut. By doing so, magpies reinforced the quality of seed dispersal effectiveness, as they cached walnuts in locations that enhanced both seed survival and seedling emergence.
Dobbs v. Jackson and the Revival of the States' Rights Constitution
Authors: Johnson Richard
Published: October 2022

The US Supreme Court's decision in Dobbs v. Jackson Women's Health ended the federal right to an abortion, first pronounced in the 1973 case Roe v. Wade. Dobbs has immediate implications for American women, but it also exposes a growing hostility by the court to the doctrine of ‘substantive due process’ on which many other federal rights rely. This article argues that the court's weakening of substantive due process is a direct challenge to the constitutional transformation wrought by the Fourteenth Amendment following the Civil War. The amendment asserted a national standard of fundamental rights, profoundly rebalancing power away from the states. Should the Supreme Court extend the logic of Dobbs, the national basis for many substantive due process rights will be removed. The court is reviving a kind of states' rights constitutional thinking hitherto unseen by the current generation of Americans.
Electroacupuncture reduces blood glucose by regulating intestinal flora in type 2 diabetic mice
Authors: An Jing , Wang Lingli , Song Shuangning , Tian Lugao , Liu Qingqing , Mei Minhui , Li Wenhua , Liu Shi
Published: October 2022

Background

The development of diabetes is closely related to the gut microbiota in recent studies, which can be influenced by intestinal motility. A few studies report that electroacupuncture (EA) can lower blood glucose. EA can promote colonic motility and influence gut microbes. In this study, we explored the effect of the EA on blood glucose level in mice with type 2 diabetes (T2D) and its mechanism.

Methods

The T2D mice model, fecal microbiota transplantation mice model, and KitW/Wv mice model （Point mutation of mouse W locus encoding kit gene）were used to investigate the effect of EA on blood glucose as well as the mechanism; The blood glucose and insulin resistance level and the intestinal flora were evaluated. The level of intestinal junction protein, inflammatory cytokines in the serum, interstitial cells of Cajal content, and colonic motility were detected. Lastly, the IKKβ/NF‐κB‐JNK‐IRS‐1‐AKT pathway was explored.

Results

EA lowered the blood glucose level, altered the gut microbiota, and promoted colonic motility in T2D mice. EA‐altered microbiota decreased the blood glucose level and insulin resistance in the antibiotics‐treated diabetic mice. EA increased tight junction protein, lowered inflammatory factors, and regulated the IKKβ/NF‐κB‐JNK‐IRS‐1‐AKT pathway in the liver and muscles. EA could not reduce the blood glucose and regulated gut microbiota in the KitW/Wv mice model.

Conclusions

EA promoted intestinal motility to regulate the intestinal flora, thereby reducing the level of systemic inflammation, and ultimately lowering the blood glucose by the IKKβ/NF‐κB‐JNK‐IRS‐1‐AKT signal pathway.
Sequencing our way to more accurate community abundance
Authors: Brennan Georgina L.
Published: October 2022

Over the last two decades, there has been a huge increase in our understanding of microbial diversity, structure and composition enabled by high‐throughput sequencing technologies. Yet, it is unclear how the number of sequences translates to the number of cells or species within the community. In some cases, additional observational data may be required to ensure relative abundance patterns from sequence reads are biologically meaningful. The goal of DNA‐based methods for biodiversity assessments is to obtain robust community abundance data, simultaneously, from environmental samples. In this issue of Molecular Ecology Resources, Pierella Karlusich et al. (2022) describe a new method for quantifying phytoplankton cell abundance. Using Tara Oceans data sets, the authors propose the photosynthetic gene psbO for reporting accurate relative abundance of the entire phytoplankton community from metagenomic data. The authors demonstrate higher correlations with traditional optical methods (including microscopy and flow cytometry), using their new method, improving upon molecular abundance assessments using multicopy marker genes. Furthermore, to facilitate application of their approach, the authors curated a psbO gene database for accessible taxonomic queries. This is an important step towards improving species abundance estimates from molecular data and eventually reporting of absolute species abundance, enhancing our understanding of community dynamics.
Predictors of taxonomic splitting and its role in primate conservation
Authors: Creighton M. J. A. , Luo A. Q. , Reader S. M. , Mooers A. Ø.
Published: October 2022

Species are the main unit used to measure biodiversity, but different preferred operational criteria can lead to very different delineations. For instance, named primate species have more than doubled in number since 1982. Such increases have been partly attributed to a shift away from the “biological species concept” (BSC) in favor of less inclusive species criteria. Critics of recent changes in primate taxonomy have suggested taxonomic splitting may be biased toward certain clades and have unfavorable consequences for conservation. Here, we explore predictors of taxonomic splitting across primate taxa since the initial shift away from the BSC nearly 40 years ago. We do not find evidence that net diversification rate, the rate of lineage formation over evolutionary time, is significantly linked to splitting, contrary to expectations if new species concepts and taxonomic methods identify incipient species. We also do not find evidence that research effort in fields where work has been suggested to motivate splitting is associated with increases in species numbers among genera. To test the suggestion that splitting groups is likely to increase their perceived risk of extinction, we test whether genera that have undergone more splitting have also observed a greater increase in their proportion of threatened species since the initial shift away from older taxonomic methods. We find no cohesive signal of taxonomic splitting leading to higher threat probabilities across primate genera. Thus, our analysis suggests that the threat statuses of primate species are not being overwhelmingly driven by splitting. Regardless, we echo warnings that it is unwise for conservation to be reliant on taxonomic stability. Species (however defined) are not independent from one another, thus, monitoring and managing them as such may not meet the overarching goal of conserving biodiversity.
Macro and microanatomy of some organs of a juvenile male Ganges River dolphin (Platanista gangetica spp. gangetica)
Authors: Shil Subrata Kumar , Zahangir Md. Mahiuddin , Das Bhajan Chandra , Rahman Mohammad Mahbubur , Yadav Saroj Kumar , Kibria Md. Manzoorul , Zonaed Siddiki AMAM
Published: October 2022

Ganges River dolphins (Platanista gangetica spp. gangetica) are air‐breathing, warm‐blooded mammals endemic to the Ganges and Karnaphuli rivers of the Indian subcontinent. Nevertheless, very little basic histomorphological research has been conducted on this endangered species. Therefore, this study aimed to describe the morphological features of different organs of P. gangetica. Despite becoming aquatic animals, they showed similarities with terrestrial mammals, such as the pair of lungs and an apical bronchus in the respiratory system, which are pretty standard in ruminants and pigs. However, unlike the terrestrial animal, the tracheobronchial tree was stiffer due to circularly arranged anastomosing plates of the hyaline cartilaginous ring in the trachea, cartilaginous plates in the bronchiole, and thick alveolar septa. The digestive system showed a three‐chambered mechanical and glandular stomach similar to the artiodactyles. However, the intestine showed smaller caecum like the monogastric mammal. The urogenital system showed lobulated kidneys, a urinary bladder, a fibroelastic penis with sigmoid flexure, and a long urethral process similar to some terrestrial ruminants. Considering the aquatic environment, all those modifications, unlike terrestrial mammals, are necessary for their adaptation. Thus, this research will broadly help our clinicians and conservationist to take further steps toward disease diagnosis and monitoring of marine health of this endangered species.
Bilateral patellar agenesis in dog: A case report
Authors: Lage Maíra Harumi Higa , Pozavski Júlia Augusta Rocha , Lamounier Alysson Rodrigo , de Melo Eliane Gonçalves
Published: October 2022

A bilateral patellar agenesis is an extremely rare congenital condition in which the patient does not develop both patellas and can present secondary alterations as bone, muscle and postural changes. There are some hypotheses that it has a genetic background presenting dominant characteristic. It is not yet standardized a gold treatment for this affection, but according to rare reports, clinical and surgical treatments are possible. This is a case report based on imagining exams of a mix breed male puppy that was born with bilateral patellar agenesis, an affection not yet reported in canine species.
Deep‐learning model associating lateral cervical radiographic features withCormack–Lehanegrade 3 or 4 glottic view
Authors: Cho H.‐Y. , Lee K. , Kong H.‐J. , Yang H.‐L. , Jung C.‐W. , Park H.‐P. , Hwang J. Y. , Lee H.‐C.
Published: October 2022

Unanticipated difficult laryngoscopy is associated with serious airway‐related complications. We aimed to develop and test a convolutional neural network‐based deep‐learning model that uses lateral cervical spine radiographs to predict Cormack–Lehane grade 3 or 4 direct laryngoscopy views of the glottis. We analysed the radiographs of 5939 thyroid surgery patients at our hospital, 253 (4%) of whom had grade 3 or 4 glottic views. We used 10 randomly sampled datasets to train a model. We compared the new model with six similar models (VGG, ResNet, Xception, ResNext, DenseNet and SENet). The Brier score (95%CI) of the new model, 0.023 (0.021–0.025), was lower (‘better’) than the other models: VGG, 0.034 (0.034–0.035); ResNet, 0.033 (0.033–0.035); Xception, 0.032 (0.031–0.033); ResNext, 0.033 (0.032–0.033); DenseNet, 0.030 (0.029–0.032); SENet, 0.031 (0.029–0.032), all p < 0.001. We calculated mean (95%CI) of the new model for: R2, 0.428 (0.388–0.468); mean squared error, 0.023 (0.021–0.025); mean absolute error, 0.048 (0.046–0.049); balanced accuracy, 0.713 (0.684–0.742); and area under the receiver operating characteristic curve, 0.965 (0.962–0.969). Radiographic features around the hyoid bone, pharynx and cervical spine were associated with grade 3 and 4 glottic views.
Childbearing at the margins: A systematic metasynthesis of sexual and gender diverse childbearing experiences
Authors: Soled Kodiak Ray Sung , Niles Paulomi Mimi , Mantell Elise , Dansky Mars , Bockting Walter , George Maureen
Published: October 2022

Background

The reproductive and perinatal health of sexual and gender‐diverse (SGD) individuals is a research priority area for the National Institutes of Health. Over the past decade, this childbearing population has been the focus of several qualitative studies providing the opportunity to evaluate and synthesize the qualitative literature on SGD childbearing experiences in a metasynthesis.

Methods

We conducted a literature search of four databases to identify original research published from January 2011 through June 2021. These results were augmented by forward and backward searching strategies. Two authors independently screened studies. All qualitative studies of the childbearing experience were eligible. Data were extracted and inductively coded using conventional content analysis, and studies underwent a quality appraisal by two authors.

Results

From 2396 articles, 127 full‐text articles were screened, and 25 were included in this synthesis. Three overarching themes were identified: (a) Systematic Invisibility; (b) Creating Personhood Through Parenthood; and (c) Resilient Narratives of Childbearing.

Conclusions

Relative to heterosexual and cisgender parents, SGD childbearing parents experience unique structural and interpersonal challenges and employ critically important resilience strategies and coping techniques to manage an overwhelming heterocisnormative experience. These findings provide an important target for health care organizations and professionals to improve SGD perinatal health. In addition, this metasynthesis identified persistent gaps in our understanding of this marginalized childbearing population, which have important implications for reducing health disparities that SGD parents experience.