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Cerebral palsy (CP) describes some upper motoneuron disorders due to non‐progressive disturbances occurring in the developing brain that cause progressive changes to muscle. While longer sarcomeres increase muscle stiffness in patients with CP compared to typically developing (TD) patients, changes in extracellular matrix (ECM) architecture can increase stiffness. Our goal was to investigate how changes in muscle and ECM architecture impact muscle stiffness, gait and joint function in CP. Gracilis and adductor longus biopsies were collected from children with CP undergoing tendon lengthening surgery for hamstring and hip adduction contractures, respectively. Gracilis biopsies were collected from TD patients undergoing anterior cruciate ligament reconstruction surgery with hamstring autograft. Muscle mechanical testing, two‐photon imaging and hydroxyproline assay were performed on biopsies. Corresponding data were compared to radiographic hip displacement in CP adductors (CPA), gait kinematics in CP hamstrings (CPH), and joint range of motion in CPA and CPH. We found at matched sarcomere lengths muscle stiffness and collagen architecture were similar between TD and CP hamstrings. However, CPH stiffness (R2 = 0.1973), collagen content (R2 = 0.5099) and cross‐linking (R2 = 0.3233) were correlated to decreased knee range of motion. Additionally, we observed collagen fibres within the muscle ECM increase alignment during muscular stretching. These data demonstrate that while ECM architecture is similar between TD and CP hamstrings, collagen fibres biomechanics are sensitive to muscle strain and may be altered at longer in vivo sarcomere lengths in CP muscle. Future studies could evaluate the impact of ECM architecture on TD and CP muscle stiffness across in vivo operating ranges. Key points: At matched sarcomere lengths, gracilis muscle mechanics and collagen architecture are similar in TD patients and patients with CP.In both TD and CP muscles, collagen fibres dynamically increase their alignment during muscle stretching.Aspects of muscle mechanics and collagen architecture are predictive of in vivo knee joint motion and radiographic hip displacement in patients with CP.Longer sarcomere lengths in CP muscle in vivo may alter collagen architecture and biomechanics to drive deficits in joint mobility and gait function. [ABSTRACT FROM AUTHOR]

Tall fescue (Festuca arundinacea Schreb.) is a perennial C3 grass species usually associated with the endophyte fungus Epichloë coenophiala that enhances tolerance to biotic and abiotic stresses. Given that the proportion of infected tall fescue plants in the grasslands of the Flooding Pampa (Argentina) has been progressively increasing, it is proposed that endophytes confer tolerance to the stresses characteristic of that environment, especially flooding. Plants from a naturalized population and a commercial cultivar were grown, both with and without endophyte (wild type and AR584 respectively). The plants were subjected to two submergence treatments (i.e., control and partial submergence) in two development stages (5‐leaf stage and beginning of the elongation of internodes). Plant performance (aerial and root biomass, root aerenchyma formation, total root length and root diameter, proportion of reproductive tillers, number of panicles and seeds produced) and endophyte transmission to progeny were evaluated. Endophytes did not alter the ecological fitness of plants under partial submergence. Independently of the water condition, the symbiosis was linked to low biomass in plants from the naturalized population, while the opposite occurred in plants from the cultivar. Partial submergence did not affect the germination of the seeds produced, nor the transmission of the endophyte to the seedlings that originated from them. Our work suggests that the invasion ability of tall fescue in the Flooding Pampa grasslands is not related to an endophyte‐mediated improvement of plants to tolerate water excess. [ABSTRACT FROM AUTHOR]

The reduction in friction is a desired property in many industries. Some of the applications include the movement of liquid or slurry through a pipeline in oil or mining, the grinding of one metal on another during fabrication, metal on paper in the making of nearly any paper product, to even something closer to home with the movement of a brush or comb through one's hair. Friction yields higher degrees of strain or stress on one or both of the substrates. This can be costly due to energy requirements, wear of equipment, or even breakage of the substrate. Even though the need exists in so many industries, the mechanisms of lubricity vary enough in each that there really is not a universal lubricity aid that can successfully be applied across the different industries. A family of novel lubricity aids based on alkyl polyglucosides have been synthesized and evaluated in the lab on both metal/metal friction reduction as well as comb/hair friction reduction. One of the modified alkyl polyglucosides has yielded excellent reduction in friction in both applications. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study is to investigate the neurovascular bundle (NVB) as a potential orthodontic relapse factor. The mechanical properties and the forces generated in the NVB after orthodontic extrusion are explored. Materials and Methods: Six NVBs branching from the inferior alveolar nerve to the apices of the mandibular canines and premolars of mature pigs were harvested. Stress relaxation tests were conducted. A standard linear solid model (SLS) was utilized to simulate the orthodontic extrusion of a single rooted tooth with NVB length and cross‐sectional diameter of 3.6 and 0.5 mm, respectively, so the NVB was stretched 10% and 20% of its original length. The maximum force within the NVB was then calculated. Results: Based on our data, the average Young's modulus before relaxation (E0), after relaxation (EP) and the difference between Young's moduli before and after relaxation (ES) were 324 ± 123, 173 ± 73 and 151 ± 52 kPa, respectively. The theoretical force within the NVB stretched to 10% and 20% strain was 3 and 5 mN, respectively. Conclusion: The data from our study indicate that the NVB exhibits stress relaxation, a characteristic trait of viscoelastic materials. SLS model simulation predicted residual forces around 5 mN for elongation up to 20%. We observed strain hardening with additional elongation, which has the potential to cause forces to increase exponentially. Therefore, tensile forces in the NVB should not be ruled out as a contributor to orthodontic relapse, especially in adult patients who may have decreased adaptability of their NVB. Further preclinical and clinical models should be developed to further clarify what is the contribution of the NVB to orthodontic relapse. [ABSTRACT FROM AUTHOR]

Introduction: Zika virus (ZIKV) is a human teratogen that causes congenital Zika syndrome (CZS). AXL, TLR3, and STAT2 are proteins involved in the ZIKV's entry into cells (AXL) and host's immune response (TLR3 and STAT2). In this study, we evaluated the role of genetic polymorphisms in these three genes as risk factors to CZS, and highlighted which proteins that interact with them could be important for ZIKV infection and teratogenesis. Materials and methods: We evaluate eighty-eight children exposed to ZIKV during the pregnancy, 40 with CZS and 48 without congenital anomalies. The evaluated polymorphisms in AXL (rs1051008), TLR3 (rs3775291), and STAT2 (rs2066811) were genotyped using TaqMan® Genotyping Assays. A protein-protein interaction network was created in STRING database and analyzed in Cytoscape software. Results: We did not find any statistical significant association among the polymorphisms and the occurrence of CZS. Through the analyses of the network composed by AXL, TLR3, STAT2 and their interactions targets, we found that EGFR and SRC could be important proteins for the ZIKV infection and its teratogenesis. Conclusion: In summary, our results demonstrated that the evaluated polymorphisms do not seem to represent risk factors for CZS; however, EGFR and SRC appear to be important proteins that should be investigated in future studies. [ABSTRACT FROM AUTHOR]

Summary: Software defined network (SDN) is a paradigm that emphasizes the separation of the control plane from the data plane, offering advantages such as flexibility and programmability. However, from a security perspective, SDN also introduces new vulnerabilities due to the communication required between these planes. SYN Flood attacks are typical distributed denial‐of‐service (DDoS) attacks that especially challenge network administrators since they produce a large volume of semi‐open TCP connections to a target, compromising its availability. Most of the current solutions to detect and mitigate these attacks are designed to operate at the control plane, imposing an additional overhead on controller functions. Moreover, traffic‐blocking mechanisms, a widely used alternative to protect network resources, have the drawback of restricting legitimate traffic. This work proposes DataPlane‐ML, an integrated solution to detect and mitigate DDoS attacks on SDN, acting directly in the data plane. DataPlane‐ML uses machine learning techniques for attack detection and a mitigation solution based on the node's reputation to avoid blocking legitimate traffic during an attack. Experimental results show that DataPlane‐ML is ≈26%$$ \approx 26\% $$ faster than statistical‐based solutions for attack detection while presenting better accuracy. Moreover, the DataPlane‐ML mitigation solution can preserve more than 95%$$ 95\% $$ of legitimate traffic during an attack. [ABSTRACT FROM AUTHOR]

Observations from a granitic watershed within a Mediterranean climate reveal the hydrologic and critical zone functioning of a perennial stream headwater and its upslope contributing area within a meadow system in the Sierra Nevada, California. Chemical analysis (diagnostic tools of mixing models, end member mixing analysis, tritium, etc.) and physical data (stream stage, piezometers, soil water, snowpack, etc.) indicate there are two primary pathways of water input into a headwater stream sourced from a mountain meadow. One input is a shallower and younger subsurface pathway with water that resembles snowpack chemistry, and the other a deeper and older subsurface pathway with water that reflects the chemistry of the groundwater derived from the contributing hillslopes. Multi‐year observations reveal that regardless of snowpack amount, during the period of peak hillslope infiltration, shallow and deep pathways in the hillslope behave similarly to initiate headwater streams. However, during summer dry periods, similarities in active pathways within the meadow center are not maintained between high and low snowpack years. With less snow, perennial groundwater discharge within the meadow center is eliminated, becoming only a seasonal source at the meadow's outlet. At the meadow's edge, geophysically observed downslope thinning in saprolite thickness creates reduced lateral transmissivity and initiation points for headwater streams via enhanced groundwater discharge of upslope water. Combined, these findings suggest how loss of snowpack and critical zone structure can together mediate hydrologic function in a wet meadow system in a Mediterranean climate. Creating new understanding about the stability of hydraulic functioning in headwater wet‐meadow systems under a changing climate. Plain Language Summary: A new combination of data sets collected over several years in the Sierra Nevada Mountains of California reveal how smaller wet meadows sustain headwater streamflow, or not, during years of higher or lower snowpack or drought. The location of streamflow generation at these sites may be strongly tied to the shape and characteristics of the weathered bedrock in the shallow subsurface. Findings from this study show how underground flow pathways of water can function to promote year‐round headwater stream sources in mountain environments with wet‐winter, dry‐summer climates, when large snowpacks are present. However, long‐term the prevalence of seasonal surface flooding in these headwater wet meadows may decrease as climate warms and snowpacks continue to decline and become more variable from year to year. Key Points: During low snow years, perennial surface saturation is lost within the meadow, but streamflow is sustained year‐round at the meadow's baseExistence of these groundwater‐fed meadows is related to regular surface saturation caused by downslope thinning of saproliteTogether, this suggests that under continued snowpack decline, regular surface saturation may be lost in mountain meadow systems [ABSTRACT FROM AUTHOR]

The influence of genetic drift on population dynamics during Pleistocene glacial cycles is well understood, but the role of selection in shaping patterns of genomic variation during these events is less explored. We resequenced whole genomes to investigate how demography and natural selection interact to generate the genomic landscapes of Downy and Hairy Woodpecker, species codistributed in previously glaciated North America. First, we explored the spatial and temporal patterns of genomic diversity produced by neutral evolution. Next, we tested (i) whether levels of nucleotide diversity along the genome are correlated with intrinsic genomic properties, such as recombination rate and gene density, and (ii) whether different demographic trajectories impacted the efficacy of selection. Our results revealed cycles of bottleneck and expansion, and genetic structure associated with glacial refugia. Nucleotide diversity varied widely along the genome, but this variation was highly correlated between the species, suggesting the presence of conserved genomic features. In both taxa, nucleotide diversity was positively correlated with recombination rate and negatively correlated with gene density, suggesting that linked selection played a role in reducing diversity. Despite strong fluctuations in effective population size, the maintenance of relatively large populations during glaciations may have facilitated selection. Under these conditions, we found evidence that the individual demographic trajectory of populations modulated linked selection, with purifying selection being more efficient in removing deleterious alleles in large populations. These results highlight that while genome‐wide variation reflects the expected signature of demographic change during climatic perturbations, the interaction of multiple processes produces a predictable and highly heterogeneous genomic landscape. [ABSTRACT FROM AUTHOR]

In the last decades, there is an increasing trend for replacing petro‐based adhesives with sustainable and eco‐friendly alternatives, especially in the wood industry. In this work it was developed and characterized novolac‐type phenolic resins from the full use of the cashew nut shell liquid (CNSL), an agro‐industrial residue and a rich source of phenolic compounds, sustainable alternative to petroleum‐derived chemicals, to develop bio‐based polymers. CNSL and paraformaldehyde were reacted, using oxalic acid as a catalyst, under a solvent‐free methodology. A dark and viscous resin of high molar mass and thermally stable was obtained. The development of highly bio‐based adhesives was proposed by combining CNSL‐based novolac resin (CNSL‐nov) with commercial epoxy resin (DGEBA), as an alternative to conventional hardeners. The use of the epoxy‐novolac system proved to be efficient and promising in obtaining new highly cross‐linked polymers with excellent thermal performance and with potential for wood industry, improving the bio‐based content of high‐performance adhesive. [ABSTRACT FROM AUTHOR]

Blends of poly(lactic acid) (PLA) and amine‐terminated butadiene‐acrylonitrile (ATBN) elastomer were prepared by solution with ATBN contents of 8–20 wt%. Films were molded by liquid deposition modeling 3D printing. Fourier transform infrared (FTIR) spectroscopy showed that the terminal carboxylic groups of the PLA chains reacted with the terminal amino groups of ATBN. Water was the byproduct of this reaction, causing PLA hydrolysis and accelerating the reaction. Thermogravimetric analysis (TGA) showed that components interaction caused a loss of PLA thermal stability. Scanning electron microscopy (SEM) of the blends revealed a porous morphology and no phase separation. There was change in the elongation when compared with neat PLA. Although the addition of a telechelic elastomer could improve PLA toughness, any benefits arising from such addition seem to be neutralized by PLA chain scission due to hydrolysis and porosity, resulting from the condensation reaction. [ABSTRACT FROM AUTHOR]

Postmenopausal hot flushes are caused by lack of estradiol (E2) but their neuroendocrine basis is still poorly understood. Here, we investigated the interrelationship between norepinephrine and hypothalamic neurons, with emphasis on kisspeptin neurons in the arcuate nucleus (ARC), as a regulatory pathway in the vasomotor effects of E2. Ovariectomized (OVX) rats displayed increased tail skin temperature (TST), and this increase was prevented in OVX rats treated with E2 (OVX + E2). Expression of Fos in the hypothalamus and the number of ARC kisspeptin neurons coexpressing Fos were increased in OVX rats. Likewise, brainstem norepinephrine neurons of OVX rats displayed higher Fos immunoreactivity associated with the increase in TST. In the ARC, the density of dopamine‐ß‐hydroxylase (DBH)‐immunoreactive (ir) fibers was not altered by E2 but, importantly, DBH‐ir terminals were found in close apposition to kisspeptin cells, revealing norepinephrine inputs to ARC kisspeptin neurons. Intracerebroventricular injection of the α2‐adrenergic agonist clonidine (CLO) was used to reduce central norepinephrine release, confirmed by the decreased 3‐methoxy‐4‐hydroxyphenylglycol/norepinephrine ratio in the preoptic area and ARC. Accordingly, CLO treatment in OVX rats reduced ARC Kiss1 mRNA levels and TST to the values of OVX + E2 rats. Conversely, CLO stimulated Kiss1 expression in the anteroventral periventricular nucleus (AVPV) and increased luteinizing hormone secretion. These findings provide evidence that augmented heat dissipation in OVX rats involves the increase in central norepinephrine that modulates hypothalamic areas related to thermoregulation, including ARC kisspeptin neurons. This neuronal network is suppressed by E2 and its imbalance may be implicated in the vasomotor symptoms of postmenopausal hot flushes. [ABSTRACT FROM AUTHOR]

The COVID‐19 pandemic caused by SARS‐CoV‐2 infection has led to socio‐economic shutdowns and the loss of over 5 million lives worldwide. There is a need for the identification of therapeutic targets to treat COVID‐19. SARS‐CoV‐2 spike is a target of interest for the development of therapeutic targets. We developed a robust SARS‐CoV‐2 S spike expression and purification protocol from insect cells and studied four recombinant SARS‐CoV‐2 spike protein constructs based on the original SARS‐CoV‐2 sequence using a baculovirus expression system: a spike protein receptor‐binding domain that includes the SD1 domain (RBD) coupled to a fluorescent tag (S‐RBD‐eGFP), spike ectodomain coupled to a fluorescent tag (S‐Ecto‐eGFP), spike ectodomain with six proline mutations and a foldon domain (S‐Ecto‐HexaPro(+F)), and spike ectodomain with six proline mutations without the foldon domain (S‐Ecto‐HexaPro(‐F)). We tested the yield of purified protein expressed from the insect cell lines Spodoptera frugiperda (Sf9) and Trichoplusia ni (Tni) and compared it to previous research using mammalian cell lines to determine changes in protein yield. We demonstrated quick and inexpensive production of functional glycosylated spike protein of high purity capable of recognizing and binding to the angiotensin converting enzyme 2 (ACE2) receptor. To further confirm functionality, we demonstrate binding of eGFP fused construct of the spike ectodomain (S‐Ecto‐eGFP) to surface ACE2 receptors on lung epithelial cells by flow cytometry analysis and show that it can be decreased by means of receptor manipulation (blockade or downregulation). [ABSTRACT FROM AUTHOR]

This work reports on the first identification of sapphirine‐bearing ultrahigh‐temperature (UHT) metamorphic rocks within the Borborema Province, in NE Brazil. The investigated UHT diatexites outcrop in the Arapiraca Complex, a high‐grade Palaeoproterozoic block embedded within the Neoproterozoic metavolcano‐sedimentary sequence of the Sergipano fold‐and‐thrust belt. A sapphirine‐bearing diatexite sample preserves two distinct residual mineral associations as inclusions in cordierite poikiloblasts: a volumetrically dominant silica‐saturated, garnet–sillimanite–orthopyroxene–quartz domain, and a restricted silica‐undersaturated, sapphirine–magnetite–spinel–corundum domain. Phase equilibrium modelling for the whole‐rock bulk composition constrains the reactions preserved in the silica‐saturated domain, which, coupled with reintegrated ternary feldspar thermometry and Al‐in‐orthopyroxene thermobarometry, indicates peak UHT metamorphism occurring at ~970°C/8.5 kbar followed by a clockwise near isobaric cooling stage crossing the H2O‐undersaturated solidus at ~910°C/7.7 kbar. The T–MSiO2 and P–T phase equilibrium models reveal that the stabilization of magnetite‐spinel in the silica‐undersaturated domain can be a product of domanial SiO2‐depletion ascribed to inherited compositional banding and progressive melt‐loss episodes. The appearance of sapphirine as thin coronae around previously formed magnetite‐spinel cores requires an increase in the bulk silica content during retrograde metamorphism. This was driven by variable degrees of chemical interaction between the silica‐undersaturated domain and trapped silica‐rich leucosomes. U–Pb dating of zircon coupled with trace element behaviour records the timing of melt crystallization between ca. 2.03 and 1.96 Ga, after peak UHT metamorphism and supporting a protracted, ca. 70 My period of melt presence in the crust. The UHT metamorphism in the Arapiraca Complex is related to a contemporaneous UHT event recorded within the São Francisco Craton and more broadly coincides with high geothermal gradients at ca. 2.0 Ga linked to the formation of the Columbia supercontinent. The integration of new petrological and geochronological data indicates that the Arapiraca Complex is a continental ribbon pulled away from the São Francisco–Congo palaeocontinent possibly during the early Neoproterozoic intermittent rifting events and opening of the Sergipano oceanic basin between ca. 0.98–0.74 Ga. During the late Neoproterozoic at ca. 0.63–0.57 Ga, the Arapiraca Complex continental ribbon was thrusted back onto the northern margin of the São Francisco Craton as an inlier of the Sergipano fold‐and‐thrust belt. [ABSTRACT FROM AUTHOR]

Controlled release systems were developed using biodegradable polymers/copolymers via polycondensation of glycerol with acids (citric, adipic, and succinic) with potassium chloride (KCl) 0, 10, 20, and 40 wt% followed by crosslinking at 120°C. Polymers were characterized by thermogravimetry, X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and UV‐Vis spectroscopy. All are thermally stable up to 200°C, therefore suitable for release in countries where temperatures reach 50°C. Fractographic analysis showed rubbery (rough and ductile) and hard (smooth and brittle) polymers depending on the acid used. The release profiles showed that hydrophilic (polar) polymers are easily hydrolyzed, generating faster release reaching 52% in 120 h. Less polar polymers delay KCl release below 20% at the same time. Therefore, it was possible to adjust the release by controlling the fertilizer content and the type of polymer, designing a fast or slow release to meet the needs of a given crop. [ABSTRACT FROM AUTHOR]

Environmental pollution at the current state of fossil fuel consumption has led clean energy devices like proton exchange membrane fuel cells (PEMFCs) to emerge as alternative energy generation solutions. However, the performance, durability, and efficiency limitations of PEMFCs have hindered their widespread adoption. Improving their performance and durability can be achieved by fundamentally understanding and tuning their catalyst layer structures and compositions. Transmission electron microscopy and scanning transmission electron microscopy have proven to be among the best characterization tools available to analyze the microstructural features of the catalyst layers of PEMFC devices. The ability to directly observe changes in catalyst materials during operation with high spatial and temporal resolutions by the means of In‐situ techniques can accelerate material development in the PEMFC field. In this article, structure, properties, and performance of PEMFC materials are reviewed, and their known degradation mechanisms are introduced. Available In‐situ TEM techniques are presented to guide the selection of suitable methods and approaches for studying the PEMFC systems. Finally, the current literature is presented on PEMFC research that has used In‐situ electrochemical liquid cell TEM to study materials evolution and degradation, highlighting the specific challenges and opportunities for applying the technique in the PEMFCs' field. [ABSTRACT FROM AUTHOR]

The 2019-2020 Australian Black Summer wildfires demonstrated that single events can have widespread and catastrophic impacts on biodiversity, causing a sudden and marked reduction in population size for many species. In such circumstances, there is a need for conservation managers to respond rapidly to implement priority remedial management actions for the most-affected species to help prevent extinctions. To date, priority responses have been biased towards high-profile taxa with substantial information bases. Here, we demonstrate that sufficient data are available to model the extinction risk for many less well-known species, which could inform much broader and more effective ecological disaster responses. Using publicly available collection and GIS datasets, combined with life-history data, we modelled the extinction risk from the 2019-2020 catastrophic Australian wildfires for 553 Australian native bee species (33% of all described Australian bee taxa). We suggest that two species are now eligible for listing as Endangered and nine are eligible for listing as Vulnerable under IUCN criteria, on the basis of fire overlap, intensity, frequency, and life-history traits: this tally far exceeds the three Australian bee species listed as threatened prior to the wildfire. We demonstrate how to undertake a wide-scale assessment of wildfire impact on a poorly understood group to help to focus surveys and recovery efforts. We also provide the methods and the script required to make similar assessments for other taxa or in other regions. [ABSTRACT FROM AUTHOR]

Discuss the impact of new diagnostic and planning technologies on the resolution of a clinical case of an upper central incisor with lateral perforation, root canal calcification and apical periodontitis. A 44‐year‐old woman sought treatment because of a colour change in an anterior tooth. The tooth had already been endodontically accessed, and she reported that two different clinicians had failed to locate the root canal. A Cone Beam Computed Tomography scan showed excessive wear and root perforation in the middle third, as well as pulp canal obliteration in the apical third. The perforation was treated using a biomaterial, and the root canal was located using guided endodontics. This treatment protocol was used to access, prepare, medicate with calcium hydroxide for 21 days and fill the root canal. Treatment results were satisfactory at 6‐month follow‐up. [ABSTRACT FROM AUTHOR]

Summary: Design flaws and vulnerabilities inherent to network protocols, devices, and services make Distributed Denial of Service (DDoS) a persisting threat in the cyberspace, despite decades of research efforts in the area. The historical vertical integration of traditional IP networks limited the solution space, forcing researchers to tweak network protocols while maintaining global compatibility and proper service to legitimate flows. The advent of Software‐Defined Networking (SDN) and advances in Programmable Data Planes (PDP) changed the state of affairs and brought novel possibilities to deal with such attacks. In summary, the ability of bringing together network intelligence to a control plane, and offloading flow processing tasks to the forwarding plane, opened up interesting opportunities for network security researchers unlike ever. In this article, we dive into recent research that relies on SDN and PDP to detect, mitigate, and prevent DDoS attacks. Our literature review takes into account the SDN layered view as defined in RFC7426 and focuses on the data, control, and application planes. We follow a systematic methodology to capture related articles and organize them into a taxonomy of DDoS defense mechanisms focusing on three facets: activity level, deployment location, and cooperation degree. From the analysis of existing work, we also highlight key research gaps that may foster future research in the field. [ABSTRACT FROM AUTHOR]

Background: Preeclampsia (PE) is a complex pregnancy syndrome characterised by maternal hypertension and organ damage after 20 weeks of gestation and is associated with an increased risk of cardiovascular disease later in life. Extracellular haemoglobin (Hb) and its metabolites heme and iron are highly toxic molecules and several defence mechanisms have evolved to protect the tissue. Objectives: We will discuss the roles of free iron, heme, Hb, and the scavenger proteins haemopexin and alpha‐1‐microglobulin in pregnancies complicated by PE and fetal growth restriction (FGR). Conclusion: In PE, oxidative stress causes syncytiotrophoblast (STB) stress and increased shedding of placental STB‐derived extracellular vesicles (STBEV). The level in maternal circulation correlates with the severity of hypertension and supports the involvement of STBEVs in causing maternal symptoms in PE. In PE and FGR, iron homeostasis is changed, and iron levels significantly correlate with the severity of the disease. The normal increase in plasma volume taking place during pregnancy is less for PE and FGR and therefore have a different impact on, for example, iron concentration, compared to normal pregnancy. Excess iron promotes ferroptosis is suggested to play a role in trophoblast stress and lipotoxicity. Non‐erythroid α‐globin regulates vasodilation through the endothelial nitric oxide synthase pathway, and hypoxia‐induced α‐globin expression in STBs in PE placentas is suggested to contribute to hypertension in PE. Underlying placental pathology in PE with and without FGR might be amplified by iron and heme overload causing oxidative stress and ferroptosis. As the placenta becomes stressed, the release of STBEVs increases and affects the maternal vasculature. [ABSTRACT FROM AUTHOR]

Aim: Our goal was to use eDNA metabarcoding to characterize fish community diversity, detect aquatic invasive species (AIS) and assess how measures of community (or AIS) diversity are influenced by lake physical and environmental covariates, measures of hydrological connectivity and human accessibility. Location: Michigan, USA. Methods: eDNA samples collected from 22 lakes were sequenced using two mitochondrial gene regions (12S and 16S rRNA). Metabarcoding data were compared to traditional fisheries survey data for a subset of lakes, and data from all 22 lakes were combined with environmental information to identify significant associations with community diversity and AIS relative abundance. Results: Occupancy modelling indicated that detection probabilities were generally higher with eDNA than traditional fisheries gear. Measures of connectivity with upstream aquatic habitats were positively associated with both AIS relative abundance and fish species diversity. We also demonstrate the use of spatial interpolation methods to map distributions of species diversity and AIS relative abundance within lakes. Main conclusions: eDNA metabarcoding methods provided information on the composition and diversity of fish assemblages and the presence of AIS in freshwater lakes that varied greatly in drainage connectivity and anthropogenic development. Our case study identified associations between environmental covariates and fish diversity or AIS relative abundance across lakes. This information is of particular importance given increasing anthropogenic disturbance, invasive species spread and associated declines in aquatic biodiversity. Incorporating eDNA metabarcoding as a supplement to traditional fisheries surveys will permit managers to identify greater numbers of taxa, including early detection of AIS, with less field effort and fish mortality. Further, eDNA methods may more accurately identify physical and biological features that correlate with diversity and abundance and allow agencies to more effectively direct AIS management activities. [ABSTRACT FROM AUTHOR]

In this study, the authors report morphological deformities in driftwood catfish Trachelyopterus galeatus (Auchenipteridae), an invasive catfish occurring in the Upper Paraná River basin, Brazil. The frequency of anomalous individuals reached 18.3% of all catches. X‐ray images showed anomalies, or total absence of structures, in the pelvic girdle. The authors also observed the absence of the adipose fin and mental barbels. These findings are of extreme importance for evidencing the anthropogenic impact on aquatic communities as the region suffers within fragmentation by dams and pollution from several human activities. This sort of information can be used in management systems and environmental monitoring, especially to protect other species and the native fish assemblage. [ABSTRACT FROM AUTHOR]

The COVID‐19 pandemic caused by SARS‐CoV‐2 has applied significant pressure on overtaxed healthcare around the world, underscoring the urgent need for rapid diagnosis and treatment. We have developed a bacterial strategy for the expression and purification of a SARS‐CoV‐2 spike protein receptor binding domain (RBD) that includes the SD1 domain. Bacterial cytoplasm is a reductive environment, which is problematic when the recombinant protein of interest requires complicated folding and/or processing. The use of the CyDisCo system (cytoplasmic disulfide bond formation in E. coli) bypasses this issue by pre‐expressing a sulfhydryl oxidase and a disulfide isomerase, allowing the recombinant protein to be correctly folded with disulfide bonds for protein integrity and functionality. We show that it is possible to quickly and inexpensively produce an active RBD in bacteria that is capable of recognizing and binding to the ACE2 (angiotensin‐converting enzyme) receptor as well as antibodies in COVID‐19 patient sera. [ABSTRACT FROM AUTHOR]

BACKGROUND The objective of this work was the development of silver nanoparticles (AgNPs) coated with humic acid (HA) and their incorporation into an enamel for antifungal activity. AgNPs were synthesized by chemical reduction using sodium borohydride as a reducing agent and coated with HA. Uncoated AgNPs were synthesized as control. AgNPs and HA‐AgNPs were characterized by ultraviolet–visible spectrophotometry, differential scanning calorimetry, dynamic light scattering, Fourier‐transform infrared spectroscopy (FTIR), atomic force microscopy and X‐ray diffraction (XRD). Size of AgNPs and HA‐AgNPs was recorded within the nano range, showing HA‐AgNPs' higher stability than non‐coated particles by presenting a single plasmatic band around 400 nm. RESULTS: Thermal analysis showed conjugated endothermic peaks, which confirms the compatibility of HA‐AgNPs. FTIR depicted absorptions between 1300 and 1000 cm−1 (CC, ArH, respectively), demonstrating that HA is adsorbed onto AgNPs. Thermogravimetric analysis showed that HA does not alter the reduction in mass loss of AgNPs, while it was found by XRD that adding HA promoted the formation of more amorphous AgNPs. The effectiveness of HA‐AgNPs was evaluated against three different fungal species. Minimum inhibitory concentration assays showed that ~0.5 mmol L−1 AgNPs was able to inhibit dermatophyte species growth. HA‐AgNPs were incorporated into a commercial enamel at a concentration of 8% and their organoleptic characteristics, drying time, centrifugation test and thermal stress were evaluated. Enamels with AgNPs kept their physicochemical properties over 21 days of storage. CONCLUSION: HA‐AgNP nail polish is thus proposed as an innovative material for onychomycosis infections. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Non‐iridescent, structural coloration in birds originates from the feather's internal nanostructure (the spongy matrix) but melanin pigments and the barb's cortex can affect the resulting color. Here, we explore how this nanostructure is combined with other elements in differently colored plumage patches within a bird. We investigated the association between light reflectance and the morphology of feathers from the back and belly plumage patches of male swallow tanagers (Tersina viridis), which look greenish‐blue and white, respectively. Both plumage patches have a reflectance peak around 550 nm but the reflectance spectrum is much less saturated in the belly. The barbs of both types of feathers have similar spongy matrices at their tips, rendering their reflectance spectra alike. However, the color of the belly feather barbs changes from light green at their tips to white closer to the rachis. These barbs lack pigments and their morphology changes considerably throughout. Toward the rachis, the barb is almost hollow, with a reduced area occupied by spongy matrix, and has a flattened shape. By contrast, the blue back feathers' barbs have melanin underneath the spongy matrix resulting in a much more saturated coloration. The color of these barbs is also even along the barbs' length. Our results suggest that the color differences between the white and greenish‐blue plumage are mostly due to the differential deposition of melanin and a reduction of the spongy matrix near the rachis of the belly feather barbs and not a result of changes in the characteristics of the spongy matrix. Research Highlights: How does a bird produce feathers of strikingly different colors?Greenish‐blue photonic structures are present in both white and blue feathers of male swallow tanagers.Color differences result mainly from the differential deposition of melanin. [ABSTRACT FROM AUTHOR]

Aim Method Results Interpretation To evaluate the mechanosensitivity of muscle satellite cells (MuSCs) and fibro‐adipogenic progenitors (FAPs) in cerebral palsy (CP) and the efficacy of the drug verteporfin in restoring cells' regenerative capacity.Muscle biopsies were collected from six children with CP and six typically developing children. MuSCs and FAPs were isolated and plated on collagen‐coated polyacrylamide gels at stiffnesses of 0.2 kPa, 8 kPa, and 25 kPa. Cells were treated with verteporfin to block mechanosensing or with dimethyl sulfoxide as a negative control. MuSC differentiation and FAP activation into myofibroblasts were measured using immunofluorescence staining.Surprisingly, MuSC differentiation was not affected by stiffness; however, stiff substrates resulted in large myonuclear clustering. Across all stiffnesses, MuSCs from children with CP had less differentiation than those of their typically developing counterparts. FAP activation into myofibroblasts was significantly higher in children with CP than their typically developing peers, but was not affected by stiffness. Verteporfin did not affect differentiation or activation in either cell population, but slightly decreased myonuclear clustering on stiff substrates.Cells from children with CP were less regenerative and more fibrotic compared to those of their typically developing counterparts, with MuSCs being sensitive to increases in stiffness. Therefore, the mechanosensitivity of MuSCs and FAPs may represent a new target to improve differentiation and activation in CP muscle. [ABSTRACT FROM AUTHOR]

Treating plant bacterial diseases is notoriously difficult because of the lack of available antimicrobials. Pseudomonas syringae pathovar syringae (Pss) is a major pathogen of cherry (Prunus avium) causing bacterial canker of the stem, leaf and fruit, impacting productivity and leading to a loss of trees. In an attempt to find a treatment for this disease, naturally occurring bacteriophage (phage) that specifically target Pss is being investigated as a biocontrol strategy. However, before using them as a biocontrol treatment, it is important to both understand their efficacy in reducing the bacterial population and determine if the bacterial pathogens can evolve resistance to evade phage infection. To investigate this, killing curve assays of five MR phages targeting Pss showed that phage resistance rapidly emerges in vitro, even when using a cocktail of the five phages together. To gain insight to the changes occurring, Pss colonies were collected three times during a 66-h killing curve assay and separately, Pss and phage were also coevolved over 10 generations, enabling the measurement of genomic and fitness changes in bacterial populations. Pss evolved resistance to phages through modifications in lipopolysaccharide (LPS) synthesis pathways. Bacterial fitness (growth) and virulence were affected in only a few mutants. Deletion of LPS-associated genes suggested that LPS was the main target receptor for all five MR phages. Later generations of coevolved phages from the coevolution experiment were more potent at reducing the bacterial density and when used with wild-type phages could reduce the emergence of phage-resistant mutants. This study shows that understanding the genetic mechanisms of bacterial pathogen resistance to phages is important for helping to design a more effective approach to kill the bacteria while minimizing the opportunity for phage resistance to manifest., (© 2024 The Author(s). Microbial Biotechnology published by John Wiley & Sons Ltd.)

Objective: To explore the relationship between walking measurements (i.e., walking speed, walking performance and walking confidence), and participation in ambulatory people with chronic stroke., Materials and Methods: Participation was measured using the mobility domain of Brazilian version of the Stroke Impact Scale 3.0. Walking measures were walking speed, assessed by 10-m Walk Test, walking performance, assessed by ABILOCO, walking confidence, assessed by mGES. Pearson correlation coefficients were used to explore the relationships between the walking measures and social participation, and step-wise multiple linear regression analysis was used to identify which walking measures would explain participation after stroke., Results: Ninety-five chronic stroke individuals (38 men), with a mean age of 67 (SD 13) years were assessed. Significant positive correlations, of high magnitude, were found between participation and all walking measures (r ≥ .53; p < .001). Regarding the regression analysis, walking confidence alone explained 44% (F = 72.4; p < .001) of the variance in participation. When perceived locomotion ability was included in the model, the explained variance increased to 48% (F = 42.8; p < .001)., Conclusion: All walking measures were correlated with social participation after stroke, but only perceived locomotion ability and walking confidence explained the variance in participation. Clinicians should be encouraged to evaluate real-life performance and personal factors that may limit community participation after stroke., (© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)