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The surveillance and detection of zoonotic pathogens in animals is essential for predicting disease transmission pathways and the risks of spillover, but challenges include the costs, ethics and technical expertise required for vertebrate trapping, serum sampling and antibody or virus screening. Surveillance using haematophagous arthropods as a sampling tool offers a unique opportunity to obtain blood samples from a wide range of vertebrate species, allowing the study of host-mosquito associations, and host exposure to pathogens. We explored vertebrate diversity and potential Ross River virus (RRV) transmission pathways by analysing blood-fed mosquitoes collected in Brisbane, Australia. Host origins were identified using barcode sequencing, and host exposure to RRV was assessed using a modified plaque reduction neutralisation test. In total, 480 blood-fed mosquitoes were collected between February 2021 and May 2022. The host origins of 346 (72%) bloodmeals were identified, with humans (73%) and cattle (9%) comprising the dominant hosts. RRV seroprevalence was high in both vertebrate species with evidence of RRV exposure in 70% (21/30) of cattle and 52% (132/253) of humans. This is a novel, non-invasive method of estimating seroprevalence in vertebrate host populations. Our results highlight the potential of blood-fed mosquitoes to provide species-specific insights into pathogen transmission dynamics. [ABSTRACT FROM AUTHOR]

Ceramics and single crystals of LaPO4 monazite doped with Eu(III) were irradiated with 14 MeV Au5+ ions at three different fluences. Changes to crystallinity, local coordination environments, and topography were probed using grazing-incidence X-ray diffraction (GIXRD), vertical scanning interferometry (VSI), scanning electron microscopy (SEM), Raman, and luminescence spectroscopy. GIXRD data of the ceramics revealed fluence dependent amorphization. A similar level of amorphization was detected for samples irradiated with 5 × 1013 ions/cm2 and 1 × 1014 ions/cm2, whereas the sample irradiated with the highest fluence of 1 × 1015 ions/cm2 appeared slightly less amorphous. VSI showed clear swelling of entire grains at the highest ion fluence, while more localized damage to grain boundaries was detected for ceramic samples irradiated at the lowest fluence. Single crystal specimens showed no pronounced topography changes following irradiation. SEM images of the ceramic irradiated at the highest fluence showed topological features indicative of grain surface melting. Raman and luminescence data showed a different degree of disorder in polycrystalline vs. single crystal samples. While changes to PO4 vibrational modes were observed in the ceramics, changes were more subtle or not present in the single crystals. The opposite was observed when probing the local Ln-O environment using Eu(III) luminescence, where the larger changes in terms of an elongation of the Eu-O (or La-O) bond and an increasing relative disorder with increasing fluence were observed only for the single crystals. The dissimilar trends observed in irradiated single crystals and ceramics indicate that grain boundary chemistry likely plays a significant role in the radiation response. [ABSTRACT FROM AUTHOR]

Several real-life problems are comprised of finite single-server acyclic queueing networks. The performance optimization of these queueing networks has been the subject of several studies. The present study extends the minimization of the total buffer area and overall service rates in the network simultaneously with the maximization of throughput. It is well known that these three objectives are conflicting. This fact leads to a multi-objective approach that the literature in the area has already addressed. Nevertheless, this study aims to demonstrate that there are algorithms with low computational costs that can produce solutions more efficiently than those obtained previously. Furthermore, the provided solutions can enhance throughput by solving a stochastic knapsack problem. The greedy procedure utilizes a technique of redistributing buffers between the queues, ensuring that the overall capacity is less than or equal to the previous overall capacity; thus, one objective is improved (the throughput) without compromising the other objective (total buffer allocation). Several computational experiments attest to the quality of this proposition. In addition, we provide a comparison with previously proposed solutions. [ABSTRACT FROM AUTHOR]

Background: Police violence is increasingly recognized as an urgent public health problem. Basic questions about police violence, however, remain unanswered, including which types of law enforcement agency are responsible for fatal police violence deaths. Methods: We estimated the proportion of police violence deaths in the U.S. (2013–2022) that were attributable to local, county, state, federal, or tribal police agencies, using mapping police violence data. We examined proportions overall, by decedent race/ethnicity, and by state. Results: Nationally, 60% of decedents were killed by municipal, 29% by county, 8% by state, and 3% by federal, police, with < 1% killed by tribal or other officers. These proportions varied by race/ethnicity, with 56% of Native American decedents killed by municipal police compared to 70–75% among other racially minoritized people. While municipal police were responsible for most deaths in most states, in the Southeast, county police predominated. In some Northeastern states (and Alaska), state police were responsible for > 40% of deaths. Conclusions: We identify wide geographic & racial/ethnic variation in the agencies responsible for fatal police violence. Findings suggest that the budgetary and infrastructural shifts required to prevent fatal police violence need to occur at multiple levels of government. [ABSTRACT FROM AUTHOR]

Parent engagement is an important aspect of parenting during childhood. However, little is known about the unique longitudinal associations of mother and father engagement with adolescents' externalizing and internalizing problem behaviors. This study uses Future of Families and Child Wellbeing Study data to examine the potential direct and indirect associations of parent engagement at age 9 on adolescent externalizing and internalizing behaviors at age 15. The analytic sample size is 1349, and at age 9, the mean age of children was 9.40 years (SD = 0.37). Forty-eight percent of children were female and 68% of them were from the married families. The results show that while controlling for mother engagement, higher father engagement at age 9 was directly associated with fewer adolescent internalizing behaviors, only among adolescent boys and in married families. In addition, among adolescent boys, father engagement had an indirect association with externalizing behaviors through father–child closeness. Mother engagement, however, is only found to have an indirect association with adolescents' externalizing and internalizing behaviors through maternal hostility (while controlling for father engagement). The results for mother engagement held for boys and in married families only. The findings indicate that both mother and father engagement during childhood is important and helpful to prevent adolescent problem behaviors directly or indirectly via parent–child relationship. [ABSTRACT FROM AUTHOR]

The spatial organization of eukaryotic genomes is linked to their biological functions, although it is not clear how this impacts the overall evolution of a genome. Here, we uncover the three-dimensional (3D) genome organization of the phytopathogen Verticillium dahliae, known to possess distinct genomic regions, designated adaptive genomic regions (AGRs), enriched in transposable elements and genes that mediate host infection. Short-range DNA interactions form clear topologically associating domains (TADs) with gene-rich boundaries that show reduced levels of gene expression and reduced genomic variation. Intriguingly, TADs are less clearly insulated in AGRs than in the core genome. At a global scale, the genome contains bipartite long-range interactions, particularly enriched for AGRs and more generally containing segmental duplications. Notably, the patterns observed for V. dahliae are also present in other Verticillium species. Thus, our analysis links 3D genome organization to evolutionary features conserved throughout the Verticillium genus. The spatial organization of eukaryotic genomes is linked to their biological functions. Here, the authors study the 3D genome organization of the phytopathogenic fungus Verticillium dahliae, revealing links to evolutionary features conserved throughout the Verticillium genus. [ABSTRACT FROM AUTHOR]

The large-scale conversion of N2 and H2 into NH3 (refs. 1,2) over Fe and Ru catalysts3 for fertilizer production occurs through the Haber–Bosch process, which has been considered the most important scientific invention of the twentieth century4. The active component of the catalyst enabling the conversion was variously considered to be the oxide5, nitride2, metallic phase or surface nitride6, and the rate-limiting step has been associated with N2 dissociation7–9, reaction of the adsorbed nitrogen10 and also NH3 desorption11. This range of views reflects that the Haber–Bosch process operates at high temperatures and pressures, whereas surface-sensitive techniques that might differentiate between different mechanistic proposals require vacuum conditions. Mechanistic studies have accordingly long been limited to theoretical calculations12. Here we use X-ray photoelectron spectroscopy—capable of revealing the chemical state of catalytic surfaces and recently adapted to operando investigations13 of methanol14 and Fischer–Tropsch synthesis15—to determine the surface composition of Fe and Ru catalysts during NH3 production at pressures up to 1 bar and temperatures as high as 723 K. We find that, although flat and stepped Fe surfaces and Ru single-crystal surfaces all remain metallic, the latter are almost adsorbate free, whereas Fe catalysts retain a small amount of adsorbed N and develop at lower temperatures high amine (NHx) coverages on the stepped surfaces. These observations indicate that the rate-limiting step on Ru is always N2 dissociation. On Fe catalysts, by contrast and as predicted by theory16, hydrogenation of adsorbed N atoms is less efficient to the extent that the rate-limiting step switches following temperature lowering from N2 dissociation to the hydrogenation of surface species.Using X-ray photoelectron spectroscopy, the surface composition of iron and ruthenium catalysts during ammonia synthesis at pressures up to 1 bar and temperatures as high as 723 K can be revealed. [ABSTRACT FROM AUTHOR]

Bartonella spp. are intracellular hemotropic bacteria primarily transmitted by arthropod vectors to various mammalian hosts, including humans. In this study, we conducted a survey on wild populations of sigmodontine rodents, Akodon azarae and Oxymycterus rufus, inhabiting the Paraná River delta region. The study involved eight grids organized in a crossed 2 × 2 design, where four of the grids were exposed to cattle while the other four were not, and four grids were located in implanted forest while the remaining four were in natural grasslands. Our objective was to examine whether the occurrence of Bartonella spp. in rodents was associated with silvopastoral activities (cattle raising associated with timber production) conducted in the region. Additionally, we evaluated the associations between Bartonella infection and other environmental and host factors. We present compelling evidence of a significant positive association between Bartonella prevalence and the presence of implanted forests and cattle. Furthermore, we identified the presence of a Bartonella genotype related to the pathogen Bartonella rochalimaea, infecting both A. azarae and Ox. rufus. These findings suggest that anthropogenic land-use changes, particularly the development of silvopastoral practices in the region, may disrupt the dynamics of Bartonella. [ABSTRACT FROM AUTHOR]

Three-dimensional hydrogel-based organ-like cultures can be applied to study development, regeneration, and disease in vitro. However, the control of engineered hydrogel composition, mechanical properties and geometrical constraints tends to be restricted to the initial time of fabrication. Modulation of hydrogel characteristics over time and according to culture evolution is often not possible. Here, we overcome these limitations by developing a hydrogel-in-hydrogel live bioprinting approach that enables the dynamic fabrication of instructive hydrogel elements within pre-existing hydrogel-based organ-like cultures. This can be achieved by crosslinking photosensitive hydrogels via two-photon absorption at any time during culture. We show that instructive hydrogels guide neural axon directionality in growing organotypic spinal cords, and that hydrogel geometry and mechanical properties control differential cell migration in developing cancer organoids. Finally, we show that hydrogel constraints promote cell polarity in liver organoids, guide small intestinal organoid morphogenesis and control lung tip bifurcation according to the hydrogel composition and shape. Organ-like 3D cultures are advanced model system for biology and medicine limited by their uncontrolled cell self-assembly. Here, the authors develop a hydrogel-in-hydrogel bioprinting approach to dynamically control the growth landscape of a broad range of living 3D cell cultures. [ABSTRACT FROM AUTHOR]

In traditional semantic segmentation, knowing about all existing classes is essential to yield effective results with the majority of existing approaches. However, these methods trained in a Closed Set of classes fail when new classes are found in the test phase, not being able to recognize that an unseen class has been fed. This means that they are not suitable for Open Set scenarios, which are very common in real-world computer vision and remote sensing applications. In this paper, we discuss the limitations of Closed Set segmentation and propose two fully convolutional approaches to effectively address Open Set semantic segmentation: OpenFCN and OpenPCS. OpenFCN is based on the well-known OpenMax algorithm, configuring a new application of this approach in segmentation settings. OpenPCS is a fully novel approach based on feature-space from DNN activations that serve as features for computing PCA and multi-variate gaussian likelihood in a lower dimensional space. In addition to OpenPCS and aiming to reduce the RAM memory requirements of the methodology, we also propose a slight variation of the method (OpenIPCS) that uses an iteractive version of PCA able to be trained in small batches. Experiments were conducted on the well-known ISPRS Vaihingen/Potsdam and the 2018 IEEE GRSS Data Fusion Challenge datasets. OpenFCN showed little-to-no improvement when compared to the simpler and much more time efficient SoftMax thresholding, while being some orders of magnitude slower. OpenPCS achieved promising results in almost all experiments by overcoming both OpenFCN and SoftMax thresholding. OpenPCS is also a reasonable compromise between the runtime performances of the extremely fast SoftMax thresholding and the extremely slow OpenFCN, being able to run close to real-time. Experiments also indicate that OpenPCS is effective, robust and suitable for Open Set segmentation, being able to improve the recognition of unknown class pixels without reducing the accuracy on the known class pixels. We also tested the scenario of hiding multiple known classes to simulate multimodal unknowns, resulting in an even larger gap between OpenPCS/OpenIPCS and both SoftMax thresholding and OpenFCN, implying that gaussian modeling is more robust to settings with greater openness. [ABSTRACT FROM AUTHOR]

Cr-doped UO2 is a leading accident tolerant nuclear fuel where the complexity of Cr chemical states in the bulk material has prevented acquisition of an unequivocal understanding of the redox chemistry and mechanism for incorporation of Cr in the UO2 matrix. To resolve this, we have used electron paramagnetic resonance, high energy resolution fluorescence detection X-ray absorption near energy structure and extended X-ray absorption fine structure spectroscopic measurements to examine Cr-doped UO2 single crystal grains and bulk material. Ambient condition measurements of the single crystal grains, which have been mechanically extracted from bulk material, indicated Cr is incorporated substitutionally for U+4 in the fluorite lattice as Cr+3 with formation of additional oxygen vacancies. Bulk material measurements reveal the complexity of Cr states, where metallic Cr (Cr0) and oxide related Cr+2 and Cr+32O3 were identified and attributed to grain boundary species and precipitates, with concurrent (Cr+3xU+41-x)O2-0.5x lattice matrix incorporation. The deconvolution of chemical states via crystal vs. powder measurements enables the understanding of discrepancies in literature whilst providing valuable direction for safe continued use of Cr-doped UO2 fuels for nuclear energy generation. Additive based UO2 nuclear fuels, which incorporate small amounts of metal oxides such as chromia (Cr2O3), are an important class of accident tolerant fuels. Here authors determine the structural-redox mechanism for Cr lattice incorporation into UO2 nuclear fuels. [ABSTRACT FROM AUTHOR]

Liquid-gated transistors (LGTs) have attracted considerable attention due to their reduced fabrication time, low cost, and potential use in several applications, such as sensors for in loco diagnosis. Here, we conducted a comparative study of performance between honey-gated (HGT) and water-gated (WGT) transistors, using ZnO as the active layer, highlighting their main electrical characteristics and potential applications. The ZnO/honey and ZnO/water interfaces are attractive for edible and bioelectronics, as both materials are non-toxic and biocompatible. The mobility–capacitance product was determined from the transfer characteristics and found to be μsCi = 2.3 ± 0.8 μF V−1 s−1, and μsCi = 4.3 ± 0.5 μF V−1 s−1 for the WGT and HGT, respectively. Both devices exhibited non-null hysteresis, which was clockwise for the WGT and counterclockwise for the HGT. This phenomenon is linked to the liquid nature of the materials used as an electrolytic dielectric. The viscosity of honey results in lower ion mobility than water, leading to a higher |VTH| shift for the HGT. On the other hand, the WGT presents higher leakage current that dominates the off-state, while in the HGT, it is dominated by the channel resistance, resulting in a high Ion/Ioff ratio of (1.2 ± 0.7) × 104. The remarkable characteristics of the HGTs show that honey has potential as an organic gate dielectric for hybrid devices. With its low leakage current and high Ion/Ioff ratio at low-voltage operation, HGT presents an exciting opportunity as a platform to study material properties. [ABSTRACT FROM AUTHOR]

Objectives: Deficits in muscle performance could be a consequence of a reduced ability of a motor neuron to increase the rate in which it discharges. This study aimed to investigate motor unit (MU) discharge properties of each triceps surae muscle (TS) and TS torque steadiness during submaximal intensities in runners with Achilles tendinopathy (AT). Methods: We recruited runners with (n = 12) and without (n = 13) mid-portion AT. MU discharge rate was analysed for each of the TS muscles, using high-density surface electromyography during 10 and 20% isometric plantar flexor contractions. Results: MU mean discharge rate was lower in the gastrocnemius lateralis (GL) in AT compared to controls. In AT, GL MU mean discharge rate did not increase as torque increased from 10% peak torque, 8.24 pps (95% CI 7.08 to 9.41) to 20%, 8.52 pps (7.41 to 9.63, p = 0.540); however, in controls, MU discharge rate increased as torque increased from 10%, 8.39 pps (7.25–9.53) to 20%, 10.07 pps (8.89–11.25, p < 0.001). There were no between-group difference in gastrocnemius medialis (GM) or soleus (SOL) MU discharge rates. We found no between-group differences in coefficient of variation of MU discharge rate in any of the TS muscles nor in TS torque steadiness. Conclusion: Our data demonstrate that runners with AT may have a lower neural drive to GL, failing to increase MU discharge rate to adjust for the increase in torque demand. Further research is needed to understand how interventions focussing on increasing neural drive to GL would affect muscle function in runners with AT. [ABSTRACT FROM AUTHOR]

We investigated differences in personality traits (Big-5) and human values amongst four groups of Brazilian students staying at home or studying abroad. Two groups came from Brazilian universities: one had no interest studying abroad (n = 112), while the other group was interested studying abroad (n = 227). The third and fourth groups were Brazilian sojourners (n = 121) and Brazilians returning to the country after finishing a degree abroad (n = 150). Results showed that students who were not interested in studying abroad had lower scores on excitement values and on the personality trait of openness when compared to the other three groups. Overall, students interested in studying abroad did not differ significantly from sojourners or returnees, except on the trait of agreeableness and the value of excitement, in which they scored lower than sojourners and returnees, respectively. [ABSTRACT FROM AUTHOR]

Density functional theory predictions of binding energies and reaction barriers provide invaluable data for analyzing chemical transformations in heterogeneous catalysis. For high accuracy, effects of band structure and coverage, as well as the local bond strength in both covalent and non-covalent interactions, must be reliably described and much focus has been put on improving functionals to this end. Here, we show that a correction from higher-level calculations on small metal clusters can be applied to improve periodic band structure adsorption energies and barriers. We benchmark against 38 reliable experimental covalent and non-covalent adsorption energies and five activation barriers with mean absolute errors of 2.2 kcal mol−1, 2.7 kcal mol−1, and 1.1 kcal mol−1, respectively, which are lower than for functionals widely used and tested for surface science evaluations, such as BEEF-vdW and RPBE. Accurately computed chemisorption energies are essential for modeling catalytic conversions in heterogeneous catalysis, but are challenging to obtain. Here authors combine two approaches to improve this situation: standard DFT applied to the extended system, and small cluster models that can be treated with higher-level computational techniques to improve the description of chemical bonding. [ABSTRACT FROM AUTHOR]

Chest radiographs allow for the meticulous examination of a patient's chest but demands specialized training for proper interpretation. Automated analysis of medical imaging has become increasingly accessible with the advent of machine learning (ML) algorithms. Large labeled datasets are key elements for training and validation of these ML solutions. In this paper we describe the Brazilian labeled chest x-ray dataset, BRAX: an automatically labeled dataset designed to assist researchers in the validation of ML models. The dataset contains 24,959 chest radiography studies from patients presenting to a large general Brazilian hospital. A total of 40,967 images are available in the BRAX dataset. All images have been verified by trained radiologists and de-identified to protect patient privacy. Fourteen labels were derived from free-text radiology reports written in Brazilian Portuguese using Natural Language Processing. Measurement(s) Chest Radiography Technology Type(s) natural language processing Factor Type(s) radiological findings/labels Sample Characteristic - Organism Homo sapiens Sample Characteristic - Environment chest organ Sample Characteristic - Location Brazil [ABSTRACT FROM AUTHOR]

The search for good electrodes processed by solution has interested several niches to produce printed solar cells, lighting emitting diodes, transistors, and photodetectors. In this context, carbon nanotube (CNT) has been reported as a promising electrode material, being suitable for several printing techniques such as inkjet, screen-printing, and spray-coating. Here, we present a successfully manufactured spray-deposited diode based on the Schottky junction between multi-walled carbon nanotubes (MWCNTs) and zinc oxide nanoparticles (ZnO-NPs), both deposited by spray. Using analytical methods, we estimated the diode series resistance as 6.2 k Ω and the ideality factor as 2.2. The good morphological characteristics of the ZnO-NP and MWCNT films resulted in a good interface, allowing the junction to achieve a high effective Schottky barrier height of 0.82 eV, high rectification ratio of 1 × 104, and low turn-on voltage of 0.55 V. [ABSTRACT FROM AUTHOR]

Knowledge of host associations of blood-feeding vectors may afford insights into managing disease systems and protecting public health. However, the ability of methods to distinguish bloodmeal sources varies widely. We used two methods—Sanger sequencing and amplicon deep sequencing—to target a 228 bp region of the vertebrate Cytochrome b gene and determine hosts fed upon by triatomines (n = 115) collected primarily in Texas, USA. Direct Sanger sequencing of PCR amplicons was successful for 36 samples (31%). Sanger sequencing revealed 15 distinct host species, which included humans, domestic animals (Canis lupus familiaris, Ovis aries, Gallus gallus, Bos taurus, Felis catus, and Capra hircus), wildlife (Rattus rattus, Incilius nebulifer, Sciurus carolinensis, Sciurus niger, and Odocoileus virginianus), and captive animals (Panthera tigris, Colobus spp., and Chelonoidis carbonaria). Samples sequenced by the Sanger method were also subjected to Illumina MiSeq amplicon deep sequencing. The amplicon deep sequencing results (average of 302,080 usable reads per sample) replicated the host community revealed using Sanger sequencing, and detected additional hosts in five triatomines (13.9%), including two additional blood sources (Procyon lotor and Bassariscus astutus). Up to four bloodmeal sources were detected in a single triatomine (I. nebulifer, Homo sapiens, C. lupus familiaris, and S. carolinensis). Enhanced understanding of vector-host-parasite networks may allow for integrated vector management programs focusing on highly-utilized and highly-infected host species. [ABSTRACT FROM AUTHOR]

Wolbachia is a genus of intracellular bacterial endosymbionts found in 20–66% of all insect species and a range of other invertebrates. It is classified as a single species, Wolbachia pipientis, divided into supergroups A to U, with supergroups A and B infecting arthropods exclusively. Wolbachia is transmitted mainly via vertical transmission through female oocytes, but can also be transmitted across different taxa by host shift (HS): the direct transmission of Wolbachia cells between organisms without involving vertically transmitted gametic cells. To assess the HS contribution, we recovered 50 orthologous genes from over 1000 Wolbachia genomes, reconstructed their phylogeny and calculated gene similarity. Of 15 supergroup A Wolbachia lineages, 10 have similarities ranging from 95 to 99.9%, while their hosts' similarities are around 60 to 80%. For supergroup B, four out of eight lineages, which infect diverse and distantly-related organisms such as Acari, Hemiptera and Diptera, showed similarities from 93 to 97%. These results show that Wolbachia genomes have a much higher similarity when compared to their hosts' genes, which is a major indicator of HS. Our comparative genomic analysis suggests that, at least for supergroups A and B, HS is more frequent than expected, occurring even between distantly-related species. [ABSTRACT FROM AUTHOR]

The diel biting activity of Aedes (Stegomyia) aegypti (L) populations was extensively investigated in the early 1900s to gain more information on the biology of Ae. aegypti, and this information was used to devise effective approaches to controlling populations of this species and protect the human population from widespread arbovirus outbreaks. However, few contemporary studies are available regarding the diel activity patterns of Ae. aegypti. To assess the diel activity patterns of Ae. aegypti in southern Florida and Texas, we conducted 96-h uninterrupted mosquito collections once each month from May through November 2019 in Miami, Florida, and Brownsville, Texas, using BG-Sentinel 2 Traps. The overall diel activity pattern in both cities was bimodal with morning and evening peak activity between 7:00 and 8:00 and between 19:00 and 20:00. There were significant daily, monthly, seasonal, and site-specific differences in activity patterns, but these differences did not affect the overall peak activity times. These differences suggest daily, monthly, seasonal, and site-specific variations in human exposure to Ae. aegypti. Our observations can be used in planning and executing Ae. aegypti vector control activities in southern Florida and southern Texas, specifically those targeting the adult mosquito populations. [ABSTRACT FROM AUTHOR]

Many mite species disperse via the air. However, most methods described for the study of aerial dispersal have some limitations in the collection and/or recovery of mites that could be improved. The aim of this study was to describe a rotatory funnel-shaped collector that directs the wind to adhesive surfaces covered with a glycerin-based solution. Tests were conducted on a soccer field at UESC, Ilhéus, Brazil, in four 8-day periods. In total, 330 mites of 52 species of Eriophyidae, Tarsonemidae, Diptilomiopidae, Iolinidae, Triophtydeidae, Astigmata, Tydeidae, Phytoseiidae, Scutacaridae, Oribatida, Ascidae, Dolichocybidae, Eupodidae, Pygmephoridae and Tenuipalpidae were collected. Of the mites captured in the first three periods, 67% were Aceria sp. (Eriophyidae), and in the fourth period 46% were Coccotydaeolus aff. bakeri and Paurotyndareus sp. (Iolinidae). Comparisons between the funnel-shaped collector with the tube-shaped rotatable model of Duffner et al. (J Pest Sci 74:1–6, 2001, adapted from Schliesske 1977) showed that the former captured >3× the number of mites and 2× the number of species. In conclusion, it is expected that the method described here could help in future pest management, and help solve ecological and behavioral problems involving airborne mite dispersal, offering a tool for monitoring, counting and identifying mites, or even other small arthropods, pollen and fungal spores, in experimental and applied studies. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the infection with Rickettsiales in ticks and birds from the main protected urban area of Buenos Aires City (Argentina). One Amblyomma aureolatum (0.2%) and one Ixodes auritulus (0.1%) were positive by PCR targeting Rickettsia 23S-5S rRNA intergenic spacer. Phylogenetic analysis shows to findings in A. aureolatum are closely to Rickettsia bellii and for I. auritulus are related to 'Candidatus Rickettsia mendelii'. One I. auritulus (0.1%) and three A. aureolatum (0.6%) were positive by PCR for a fragment of the 16S rRNA gene of the Anaplasmataceae family. The sequences obtained from A. aureolatum were phylogenetically related to Midichloriaceae endosymbionts. The sequence from I. auritulus s.l. had 100% identity with Ehrlichia sp. Magellanica from Chile and two genotypes of Ehrlichia sp. from Uruguay. The results of our study show that Rickettsia and Ehrlichia are present in ticks in the main protected urban area of Buenos Aires City. [ABSTRACT FROM AUTHOR]

Carnap's seminal 'Empiricism, Semantics and Ontology' makes important use of the notion of a framework and the related distinction between internal and external questions. But what exactly is a framework? And what role does the internal/external (I/E) distinction play in Carnap's metaontology? In an influential series of papers, Matti Eklund has recently defended a bracingly straightforward interpretation: A Carnapian framework, Eklund says, is just a natural language. To ask an internal question, then, is just to ask a question in, say, English. To try to ask an external question is to try, absurdly, to ask a question in no language at all. Finding that so trivial an I/E distinction can't help to explain Carnap's deflationary metaontology, Eklund is led to attribute to Carnap a view he calls ontological pluralism. In this paper, I show that Eklund misreads Carnap, and I argue that this misreading obscures fundamental features of Carnap's philosophy. I then defend an account of frameworks as what Carnap called semantical systems, and I place this account in the context of Carnap's philosophical program of explication. Finally, I discuss the role that frameworks and the I/E distinction play in ESO, showing that ESO provides no reason to attribute the doctrine of ontological pluralism to Carnap. [ABSTRACT FROM AUTHOR]

As a response to mass mobilizations against the political and social status quo, a multiparty agreement activated a process to replace the constitution in Chile, three decades after the country's transition to democracy. I argue that this process has three features that are not only desirable on normative grounds but also shared by successful episodes of constitutional replacement in democratic regimes: the drafting of the new text in an assembly bound by preexisting rules, inclusive mechanisms of representation and decision making, and direct citizen involvement. These features, in interaction with the popular repudiation of the elite-biased institutions inherited from the Pinochet era, might lead to a new constitutional arrangement that deepens democratization by expanding citizen rights, strengthening executive constraints, and removing restrictions on majority rule. Yet the realization of the full democratic potential of this constitutional change depends on the still uncertain ability of constitution makers to compromise on a text that is not only seen as legitimate among ordinary citizens but also promotes coherent goals, effective institutions, and good governance. [ABSTRACT FROM AUTHOR]

Bacterial biofilms are aggregates of surface-associated cells embedded in an extracellular polysaccharide (EPS) matrix, and are typically stationary. Studies of bacterial collective movement have largely focused on swarming motility mediated by flagella or pili, in the absence of a biofilm. Here, we describe a unique mode of collective movement by a self-propelled, surface-associated biofilm-like multicellular structure. Flavobacterium johnsoniae cells, which move by gliding motility, self-assemble into spherical microcolonies with EPS cores when observed by an under-oil open microfluidic system. Small microcolonies merge, creating larger ones. Microscopic analysis and computer simulation indicate that microcolonies move by cells at the base of the structure, attached to the surface by one pole of the cell. Biochemical and mutant analyses show that an active process drives microcolony self-assembly and motility, which depend on the bacterial gliding apparatus. We hypothesize that this mode of collective bacterial movement on solid surfaces may play potential roles in biofilm dynamics, bacterial cargo transport, or microbial adaptation. However, whether this collective motility occurs on plant roots or soil particles, the native environment for F. johnsoniae, is unknown. Bacterial biofilms are aggregates of surface-associated cells embedded in an extracellular polysaccharide (EPS) matrix. Here, the authors describe a unique mode of collective movement by self-propelled, surface-associated spherical microcolonies with EPS cores in the gliding bacterium Flavobacterium johnsoniae. [ABSTRACT FROM AUTHOR]

Little is known about the developmental course of informant discrepancies in adolescent aggressive behavior problems, though whether aggression increases or decreases over time depends on reporter. Evaluating discrepancies longitudinally can uncover patterns of agreement/disagreement between reporters across time and determine contexts that give rise to these differences. This study addresses longitudinal informant discrepancies by examining parent-report and adolescent report of adolescent aggressive behavior problems over time and further investigates possible contextual factors related to the longitudinal discrepancy. Five-waves (from age 11.5 to 15) of multi-informant data from the PROSPER project (N = 977; 52% female; 87% Caucasian) were used to test longitudinal change in informant discrepancies between mother-, father-, and adolescent-reported aggressive behavior problems. Results showed that parents reported more aggression than their adolescents at age 11.5 and that the discrepancy at first converged over time before diverging. By age 15, adolescents reported more aggression than their parents. Parental hostility, family status, and adolescent gender predicted change in informant discrepancies. Practical and developmental implications are discussed for assessing and determining accurate change in adolescent aggressive behavior problems. [ABSTRACT FROM AUTHOR]

We describe the basal mesoeucrocodylian Burkesuchus mallingrandensis nov. gen. et sp., from the Upper Jurassic (Tithonian) Toqui Formation of southern Chile. The new taxon constitutes one of the few records of non-pelagic Jurassic crocodyliforms for the entire South American continent. Burkesuchus was found on the same levels that yielded titanosauriform and diplodocoid sauropods and the herbivore theropod Chilesaurus diegosuarezi, thus expanding the taxonomic composition of currently poorly known Jurassic reptilian faunas from Patagonia. Burkesuchus was a small-sized crocodyliform (estimated length 70 cm), with a cranium that is dorsoventrally depressed and transversely wide posteriorly and distinguished by a posteroventrally flexed wing-like squamosal. A well-defined longitudinal groove runs along the lateral edge of the postorbital and squamosal, indicative of a anteroposteriorly extensive upper earlid. Phylogenetic analysis supports Burkesuchus as a basal member of Mesoeucrocodylia. This new discovery expands the meagre record of non-pelagic representatives of this clade for the Jurassic Period, and together with Batrachomimus, from Upper Jurassic beds of Brazil, supports the idea that South America represented a cradle for the evolution of derived crocodyliforms during the Late Jurassic. [ABSTRACT FROM AUTHOR]

Arthropod vectors are frequently exposed to a diverse assemblage of parasites, but the consequence of these infections on their biology and behavior are poorly understood. We experimentally evaluated whether the ingestion of a common protozoan parasite of avian hosts (Haemoproteus spp.; Haemosporida: Haemoproteidae) impacted the survivorship of Culex quinquefasciatus (Say) (Diptera: Culicidae). Blood was collected from wild northern cardinals (Cardinalis cardinalis) in College Station, Texas, and screened for the presence of Haemoproteus spp. parasites using microscopic and molecular methods. Experimental groups of Cx. quinquefasciatus mosquitoes were offered Haemoproteus-positive cardinal blood through an artificial feeding apparatus, while control groups received Haemoproteus-negative cardinal blood or domestic canary (Serinus canaria domestica) blood. Culex quinquefasciatus mosquitoes exposed to Haemoproteus infected cardinal blood survived significantly fewer days than mosquitoes that ingested Haemoproteus-negative cardinal blood. The survival of mosquitoes fed on positive cardinal blood had a median survival time of 18 days post-exposure and the survival of mosquitoes fed on negative cardinal blood exceeded 50% across the 30 day observation period. Additionally, mosquitoes that fed on canary controls survived significantly fewer days than cardinal negative controls, with canary control mosquitoes having a median survival time of 17 days. This study further supports prior observations that Haemoproteus parasites can be pathogenic to bird-biting mosquitoes, and suggests that Haemoproteus parasites may indirectly suppress the transmission of co-circulating vector-borne pathogens by modulating vector survivorship. Our results also suggest that even in the absence of parasite infection, bloodmeals from different bird species can influence mosquito survivorship. [ABSTRACT FROM AUTHOR]

Testicular development and function rely on interactions between somatic cells and the germline, but similar to other organs, regenerative capacity declines in aging and disease. Whether the adult testis maintains a reserve progenitor population remains uncertain. Here, we characterize a recently identified mouse testis interstitial population expressing the transcription factor Tcf21. We found that TCF21lin cells are bipotential somatic progenitors present in fetal testis and ovary, maintain adult testis homeostasis during aging, and act as potential reserve somatic progenitors following injury. In vitro, TCF21lin cells are multipotent mesenchymal progenitors which form multiple somatic lineages including Leydig and myoid cells. Additionally, TCF21+ cells resemble resident fibroblast populations reported in other organs having roles in tissue homeostasis, fibrosis, and regeneration. Our findings reveal that the testis, like other organs, maintains multipotent mesenchymal progenitors that can be potentially leveraged in development of future therapies for hypoandrogenism and/or infertility. Whether the adult testis harbours a somatic progenitor population is unknown. Here, the authors provide evidence that the testis interstitial cells expressing the transcription factor Tcf21 maintain adult testis homeostasis during aging, and act as potential reserve somatic progenitors following injury. [ABSTRACT FROM AUTHOR]

The cut-set ∂ (S) of a graph G = (V , E) is the set of edges that have one endpoint in S ⊂ V and the other endpoint in V \ S , and whenever G[S] is connected, the cut [ S , V \ S ] of G is called a connected cut. A bond of a graph G is an inclusion-wise minimal disconnecting set of G, i.e., bonds are cut-sets that determine cuts [ S , V \ S ] of G such that G[S] and G [ V \ S ] are both connected. Contrasting with a large number of studies related to maximum cuts, there exist very few results regarding the largest bond of general graphs. In this paper, we aim to reduce this gap on the complexity of computing the largest bond, and the maximum connected cut of a graph. Although cuts and bonds are similar, we remark that computing the largest bond and the maximum connected cut of a graph tends to be harder than computing its maximum cut. We show that it does not exist a constant-factor approximation algorithm to compute the largest bond, unless P = NP . Also, we show that Largest Bond and Maximum Connected Cut are NP-hard even for planar bipartite graphs, whereas Maximum Cut is trivial on bipartite graphs and polynomial-time solvable on planar graphs. In addition, we show that Largest Bond and Maximum Connected Cut are NP-hard on split graphs, and restricted to graphs of clique-width w they can not be solved in time f (w) n o (w) unless the Exponential Time Hypothesis fails, but they can be solved in time f (w) n O (w) . Finally, we show that both problems are fixed-parameter tractable when parameterized by the size of the solution, the treewidth, and the twin-cover number. [ABSTRACT FROM AUTHOR]

A novel ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) based on melting of the donor phase for the determination of Cd, Cu, and Fe in margarine samples using high-resolution continuum source electrothermal atomic absorption spectrometry (HR-CS ET AAS) is proposed. Considering that margarine is in the solid phase at room temperature, requiring heat for melting, the microextraction process was assisted by an ultrasonic bath to ensure the melting point of the samples and to increase the extraction efficiency of the analytes by UA-DLLME. After the extraction procedure, the aqueous phase was collected and directly introduced into a graphite furnace. The procedure was applied for extraction and multi-element determination, exploring the strategy of simultaneous and sequential determination of analytes by HR-CS ET AAS. A low volume of nitric acid solution in the presence of ethanol and hydrogen peroxide allowed the metals to be separated from the sample in an aqueous phase with subsequent determination by HR-CS ETAAS. In the extraction procedure, 5.0 g of each margarine sample was sonicated under heating in the presence of 100 μL of a solution containing HNO3 0.1 mol L−1, ethanol (95.1%, v v−1), and H2O2 3% (v v−1) in a volume proportion of 2:1:1. The influences of the time of extraction, temperature of extraction, and amplitude of sonication were examined, and the proposed conditions were as follows: extraction time, 10 min; temperature, 60 °C; and amplitude, 100%. Using 5 g of margarine sample, limits of detection of 0.03, 0.52, and 224 ng g−1 were obtained for Cd, Cu, and Fe, respectively. Recovery tests were performed, and the results ranged from 87 to 108% for Cd, 91 to 115% for Cu, and 85 to 112% for Fe. The results obtained by the proposed extraction procedure agreed with those obtained after wet digestion of the sample and determination by inductively coupled plasma optical emission spectrometry (ICP OES). [ABSTRACT FROM AUTHOR]

Post-zygotic mutations that generate tissue mosaicism are increasingly associated with severe congenital defects, including those arising from failed neural tube closure. Here we report that neural fold elevation during mouse spinal neurulation is vulnerable to deletion of the VANGL planar cell polarity protein 2 (Vangl2) gene in as few as 16% of neuroepithelial cells. Vangl2-deleted cells are typically dispersed throughout the neuroepithelium, and each non-autonomously prevents apical constriction by an average of five Vangl2-replete neighbours. This inhibition of apical constriction involves diminished myosin-II localisation on neighbour cell borders and shortening of basally-extending microtubule tails, which are known to facilitate apical constriction. Vangl2-deleted neuroepithelial cells themselves continue to apically constrict and preferentially recruit myosin-II to their apical cell cortex rather than to apical cap localisations. Such non-autonomous effects can explain how post-zygotic mutations affecting a minority of cells can cause catastrophic failure of morphogenesis leading to clinically important birth defects. Mutations that cause tissue mosaicism have been identified in individuals with severe congenital defects. Here, the authors show that mosaic deletion of Vangl2 in the murine neuroepithlium causes spina bifida by preventing apical constriction via reduced myosin II and tubulin organisation. [ABSTRACT FROM AUTHOR]

This work describes an exploratory experimental and in silico study of the influence of polymorphism, particle size, and physiology on the pharmacokinetics of lercanidipine hydrochloride (LHC). Equilibrium and kinetic solubility studies were performed on LHC forms I and II, as a function of pH and buffer composition. GastroPlus® was used to evaluate the potential effect of solubility differences due to polymorphism, particle size, and physiological conditions, on the drug pharmacokinetics. The results indicated that solubilities of LHC polymorphs are strongly dependent on the composition and pH of the buffer media. The concentration ratio (CI/CII) is particularly large for chloride buffer (CI/CII = 3.3–3.9) and exhibits a slightly decreasing tendency with the pH increase for all other buffers. Based on solubility alone, a higher bioavailability of form I might be expected. However, exploratory PBPK simulations suggested that (i) under usual fasted (pH 1.3) and fed (pH 4.9) gastric conditions, the two polymorphs have similar bioavailability, regardless of the particle size; (ii) at high gastric pH in the fasted state (e.g., pH 3.0), the bioavailability of form II can be considerably lower than that of form I, unless the particle size is < 20 μm. This study demonstrates the importance of investigating the effect of the buffer nature when evaluating the solubility of ionizable polymorphic substances. It also showcases the benefits of using PBPK simulations, to assess the risk and pharmacokinetic relevance of different solubility and particle size between crystal forms, for diverse physiological conditions. [ABSTRACT FROM AUTHOR]

In recent years, due to the increase of nanotechnology and the demand for innovations in cementitious materials, there has been a significant interest in research in the application of nanosilica (NS) as supplementary nano cementitious material (SNCM). The incorporation of NS in cementitious materials aims to improve its performance in specific applications, such as for high strength and durability in the concretes. Recent developments in the synthesis of the monodisperse and small size distribution of nanoparticles by functionalization methods provide a significant boost to the development of nanosilica composites with functional group grafts, called functionalized nanosilica (FNS). This review article intends to standardize the bibliographic review of FNS synthesis methods and the ways to characterize them. [ABSTRACT FROM AUTHOR]

South Texas has experienced local transmission of Zika virus and of other mosquito-borne viruses such as chikungunya virus and dengue virus in the last decades. Using a mosquito surveillance program in the Lower Rio Grande Valley (LRGV) and San Antonio, TX, from 2016 to 2018, we detected the presence of an insect-specific virus, cell fusing agent virus (CFAV), in the Aedes aegypti mosquito population. We tested 6,326 females and 1,249 males from the LRGV and 659 females from San Antonio for CFAV by RT-PCR using specific primers. Infection rates varied from 0 to 261 per 1,000 mosquitoes in the LRGV and 115 to 208 per 1,000 in San Antonio depending on the month of collection. Infection rates per 1,000 individuals appeared higher in females collected from BG Sentinel 2 traps compared to Autocidal Gravid Ovitraps, but the ratio of the percentage of infected pools did not differ by trap type. The natural viral load in individual males ranged from 1.25 x 102 to 5.50 x 106 RNA copies and in unfed females from 5.42 x 103 to 8.70 x 106 RNA copies. Gravid females were found to harbor fewer viral particles than males and unfed females. [ABSTRACT FROM AUTHOR]

Root systems are dynamic and adaptable organs that play critical roles in plant development. However, how roots grow and accumulate biomass during plant life cycle and in relation to shoot growth phenology remains understudied. A comprehensive time-dependent root morphological analysis integrated with molecular signatures is then required to advance our understanding of root growth and development. Here we studied Brachypodium distachyon rooting process by monitoring root morphology, biomass production, and C/N ratios during developmental stages. To provide insight into gene regulation that accompanies root growth, we generated comprehensive transcript profiles of Brachypodium whole-root system at four developmental stages. Our data analysis revealed that multiple biological processes including trehalose metabolism and various families of transcription factors (TFs) were differentially expressed in root system during plant development. In particular, the AUX/IAA, ERFs, WRKY, NAC, and MADS TF family members were upregulated as plant entered the booting/heading stage, while ARFs and GRFs were downregulated suggesting these TF families as important factors involved in specific phases of rooting, and possibly in regulation of transition to plant reproductive stages. We identified several Brachypodium candidate root biomass-promoting genes and cis-regulatory elements for further functional validations and root growth improvements in grasses. [ABSTRACT FROM AUTHOR]

Aedes aegypti is the main vector of arboviral diseases such as dengue, chikungunya and Zika. A key feature for disease transmission modeling and vector control planning is adult mosquito dispersal. We studied Ae aegypti adult dispersal by conducting a mark-capture study of naturally occurring Ae. aegypti from discarded containers found along a canal that divided two residential communities in Donna, Texas, USA. Stable isotopes were used to enrich containers with either 13C or 15N. Adult mosquitoes were collected outdoors in the yards of households throughout the communities with BG Sentinel 2 traps during a 12-week period. Marked mosquito pools with stable isotopes were used to estimate the mean distance travelled using three different approaches (Net, Strip or Circular) and the probability of detecting an isotopically marked adult at different distances from the larval habitat of origin. We consistently observed, using the three approaches that male (Net: 220 m, Strip: 255 m, Circular: 250 m) Ae. aegypti dispersed further in comparison to gravid (Net: 135 m, Strip: 176 m, Circular: 189 m) and unfed females (Net: 192 m, Strip: 213 m, Circular: 198 m). We also observed that marked male capture probability slightly increased with distance, while, for both unfed and gravid females, such probability decreased with distance. Using a unique study design documenting adult dispersal from natural larval habitat, our results suggest that Ae. aegypti adults disperse longer distances than previously reported. These results may help guide local vector control authorities in their fight against Ae. aegypti and the diseases it transmits, suggesting coverage of 200 m for the use of insecticides and innovative vector control tools. [ABSTRACT FROM AUTHOR]

The Middle Eocene Climatic Optimum (MECO) is a global warming event that occurred at around 40 Ma and lasted about 500 kyr. We study this event in an abyssal setting of the Tasman Sea, using the IODP Core U1511B-16R, collected during the expedition 371. We analyse magnetic, mineralogical, and chemical parameters to investigate the evolution of the sea bottom conditions at this site during the middle Eocene. We observe significant changes indicating the response to the MECO perturbation. Mn oxides, in which Mn occurs under an oxidation state around +4, indicate a high Eh water environment. A prominent Mn anomaly, occurring just above the MECO interval, indicates a shift toward higher pH conditions shortly after the end of this event. Our results suggest more acid bottom water over the Tasman abyssal plain during the MECO, and an abrupt end of these conditions. This work provides the first evidence of MECO at abyssal depths and shows that acidification affected the entire oceanic water column during this event. [ABSTRACT FROM AUTHOR]

Castor oil is an environmentally friendly alternative to hydrocarbon-based feedstocks for the synthesis of polyurethanes due to its major constituent, ricinoleic acid. This work aimed to obtain and characterize castor oil-based polyurethane (coPU) systems containing domperidone and verapamil hydrochloride, separately, as model drugs. The drug-loaded coPU systems were obtained by solvent evaporation method and were characterized by differential scanning calorimetry, thermogravimetry, Fourier transform infrared spectroscopy and X-ray powder diffraction. Additionally, dissolution studies and scanning electron microscopy were performed. Verapamil hydrochloride was successfully incorporated in coPU, once it interacted through hydrogen bonds, and this system showed as a potential candidate for sustained drug release. Domperidone precipitated during solvent evaporation, resulting in a drug suspension into the polymer matrix. However, around 20% of domperidone interacted chemically with the polymer by the reaction of the active hydrogen of domperidone imidazole groups with the terminal isocyanate of the prepolymer. Finally, the drug release profile is guided by the drug–polymer physicochemical interaction, which will depend on the drug and polymer functional groups that are stereochemically available. [ABSTRACT FROM AUTHOR]

Masonry arches are vulnerable to seismic actions. Over the last few years, extensive research has been carried out to develop strategies and methods for their seismic assessment and strengthening. The application of constant horizontal accelerations to masonry arches is a well-known quasi-static method, which approximates dynamic loading effects and quantifies their stability, while tilting plane testing is a cheap and effective strategy for experimentation of arches made of dry-stack masonry. Also, the common strengthening techniques for masonry arches are mainly focusing on achieving full strength of the system rather than stability. Through experimentation of a dry-stack masonry arch it has been shown that the capacity of an arch can be increased, and the failure controlled by defining hinge positions through reinforcement. This paper utilizes experimentally obtained results to introduce: (1) static friction and resulting mechanisms; and (2) the post-minimum mechanism reinforcement requirements into the two-dimensional limit analysis-based kinematic collapse load calculator (KCLC) software designed for the static seismic analysis of dry-stack masonry arches. Computational results are validated against a series of experimental observations based on tilt plane tests and good agreement is obtained. Discrete element models to represent the masonry arch with different hinge configurations are also developed to establish a validation trifecta. The limiting mechanism to activate collapse of arches subjected to hinge control is investigated and insights into the optimal reinforcement to be installed in the arch are derived. It is envisaged that the current modelling approach can be used by engineers to understand stability under horizontal loads and develop strengthening criteria for masonry arches of their care. [ABSTRACT FROM AUTHOR]

Objective: To compare the efficacy and safety of two post-operative drains in breast cancer patients after breast conserving surgery.Methods: This was a prospectively randomized comparative study of two drains investigated in breast cancer patients after breast conserving therapy. The Redon drain ends in a tip with 28 double perforations while the Quadrain drain features 4 flexible flaps of about 0.15 m length. The drains cost 0.28 € and 3.54 €, respectively. Primary target parameter was the duration of the drains staying in the surgical site. Secondary target parameters were pain post-surgery, seroma volume, final cosmetic result and surgical site infections.Results: A total of 88 patients were randomized, 47 and 41 received the Redon drain and the Quadrain drain, respectively. The mean duration of the drains staying in the surgical site was not different between the Redon and the Quadrain drain, 42.6 h (± 25.8 h) and 50.1 h (± 28.5 h), respectively (p = 0.1959). The post-operative pain score, seroma size, cosmetic result and surgical site infections were not different for both systems.Conclusion: The Redon drain and the new Quadrain drain were not significantly different with respect to duration in the surgical site, post-operative pain, seroma volume and cosmetic result. [ABSTRACT FROM AUTHOR]

Purpose: Conventional methods of seeding decellularized heart valves for heart valve tissue engineering have led to inconsistent results in interstitial cellular repopulation, particularly of the distal valve leaflet, and notably distinct from documented re-endothelialization. The use of bioreactor conditioning mimicking physiologic parameters has been well explored but cellular infiltration remains challenging. Non-characteristic, non-physiologic conditioning parameters within a bioreactor, such as hypoxia and cyclic chamber pressure, may be used to increase the cellular infiltration leading to increased recellularization. Methods: To investigate the effects of novel and perhaps non-intuitive bioreactor conditioning parameters, ovine aortic heart valves were seeded with mesenchymal stem cells and cultured in one of four environments: hypoxia and high cyclic pressures (120 mmHg), normoxia and high cyclic pressures, hypoxia and negative cyclic pressures (− 20 mmHg), and normoxia and negative cyclic pressures. Analysis included measurements of cellular density, cell phenotype, and biochemical concentrations. Results: The results revealed that the bioreactor conditioning parameters influenced the degree of recellularization. Groups that implemented hypoxic conditioning exhibited increased cellular infiltration into the valve leaflet tissue compared to normoxic conditioning, while pressure conditioning did not have a significant effect of recellularization. Protein expression across all groups was similar, exhibiting a stem cell and valve interstitial cell phenotype. Biochemical analysis of the extracellular matrix was similar between all groups. Conclusion: These results suggest the use of non-physiologic bioreactor conditioning parameters can increase in vitro recellularization of tissue engineered heart valve leaflets. Particularly, hypoxic culture was found to increase the cellular infiltration. Therefore, bioreactor conditioning of tissue engineered constructs need not always mimic physiologic conditions, and it is worth investigating novel or uncharacteristic culture conditions as they may benefit aspects of tissue culture. [ABSTRACT FROM AUTHOR]

Purpose: To investigate whether a training program on breast ultrasound skills including core-needle biopsies to undergraduate students can improve medical knowledge and learning satisfaction.Methods: Medical students attending mandatory classes at the Medical School of the University of Saarland received a supplemental theoretical and hands-on training program on ultrasound (US) breast screening and on US-guided core-needle biopsy using an agar-agar phantom. Experienced breast specialists and ultrasound examiners served as trainers applying Peyton's 4-step training approach. The students' theoretical knowledge and hands-on skills were tested before and after the training program, using a multiple-choice questionnaire (MCQ), the Objective Structured Clinical Examination (OSCE) and a student curriculum evaluation.Results: The MCQ results showed a significant increase of the student's theoretical knowledge (50.2-75.2%, p < 0.001). After the course, the OSCE showed a mean total of 17.3/20 points (86.5%), confirming the practical implementation of the new skills. The student curriculum evaluation in general was very positive. A total of 16/20 questions were rated between 1.2 and 1.7 (very good) and 3 questions were rated as 2.1 (good).Conclusion: Undergraduate student's medical education can be enhanced by teaching breast US skills. [ABSTRACT FROM AUTHOR]

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The standard model of precedential constraint holds that a court is equally free to modify a precedent of its own and a precedent of a superior court—overruling aside, it does not differentiate horizontal and vertical precedents. This paper shows that no model can capture the U.S. doctrine of precedent without making that distinction. A precise model is then developed that does just that. This requires situating precedent cases in a formal representation of a hierarchical legal structure, and adjusting the constraint that a precedent imposes based on the relationship of the precedent court and the instant court. The paper closes with suggestions for further improvements of the model. [ABSTRACT FROM AUTHOR]