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1.
Cryobiology ; 116: 104938, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38960349

RESUMO

It is thought that surface melting and puffing of freeze-dried amorphous materials are related to the difference between the surface temperature (Tsur) and freeze-concentrated glass transition temperature (Tg') of the materials. Although Tg' is a material-specific parameter, Tsur is affected by the type and amount of solute and freeze-drying conditions. Therefore, it will be practically useful for preventing surface melting and puffing if Tsur can be calculated using only the minimum necessary parameters. This study aimed to establish a predictive model for the surface melting and puffing of freeze-dried amorphous materials according to the calculated Tsur. First, a Tsur-predictive model was proposed under the thermodynamic equilibrium assumptions. Second, solutions with various solute mass fractions of sucrose, maltodextrin, and sucrose-maltodextrin mixture were prepared, and three material-specific parameters (Tg', unfrozen water content, and true density) were experimentally determined. According to the proposed model with the parameters, the Tsur of the samples was calculated at chamber pressures of 13, 38, and 103 Pa. The samples were freeze-dried at the chamber pressures, and their appearance was observed. As expected, surface melting and puffing occurred at calculated Tsur > Tg' with some exceptions. The water activity (aw) of the freeze-dried samples increased as the Tsur - Tg' increased. This will have resulted from surface melting and puffing, which created a covering film, thereby preventing subsequent dehydration. The observations suggest that the proposed model is also useful for predetermining the drying efficiency and storage stability of freeze-dried amorphous materials.

2.
Cureus ; 16(7): e64500, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39007016

RESUMO

Objective This study aimed to investigate the longevity and effectiveness of bioactive glass (BAG)-based dental resin infiltrants. Materials and methods The three types of BAG - 45S5 bioglass (RIS), boron-substituted (RIB), and fluoride-substituted (RIF) - were incorporated with photoinitiated dimethacrylate monomers to create experimental resin infiltrants. ICON® (CN; DMG-America, Ridgefield Park, NJ) and pure resin (PR) were used as control groups in this study. Disc-shaped samples were prepared for the experimental and control groups. The samples were challenged with the pH cycle and immersed in the artificial saliva for 30 days. On Day 0 and Day 30, the pH cycle and artificial saliva immersion, Vicker's microhardness, surface roughness, and surface morphology were investigated. Results The RIF group's disc samples showed the highest Vicker's microhardness values (78.20 ±0.06) on Day 30 of artificial saliva immersion, whereas the CN group's values were the lowest (55.99 ±0.24). Following the pH cycling, the RIF displayed the highest hardness (64.15 ±1.89) whereas the CN group's values were the lowest (33.47 ±1.28). Regarding surface roughness, on Day 30, the RIB resin group exhibited the highest (1.14 ±0.001 µm). In contrast, the CN resin showed the lowest (1.07 ±0.06 µm) values, while immersed in the artificial saliva solution. In the same duration of time, in the pH cycling solution, PR showed the least (0.85 ±0.89 µm), while RIF showed the highest roughness value (0.94 ±0.54 µm). Morphological analysis revealed that following the artificial saliva immersion, the RIB, CN, and PR exhibited smoother surfaces compared to the RIS and RIF groups. However, when immersed in the pH cycling solution, RIB and RIF showed more resistance against acid attack. Conclusions Our results revealed that the experimental resin groups performed much better than the commercial resin infiltrants following artificial saliva and pH cycling challenges.

3.
Nano Lett ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007508

RESUMO

A kagome lattice hosts a plethora of quantum states arising from the interplay between nontrivial topology and electron correlations. The recently discovered kagome magnet RMn6Sn6 (R represents a rare-earth element) is believed to showcase a kagome band closely resembling textbook characteristics. Here, we report the characterization of local electronic states and their magnetization response in YMn6Sn6 via scanning tunneling microscopy measurements under vector magnetic fields. Our spectroscopic maps reveal a spontaneously trimerized kagome electronic order in YMn6Sn6, where the 6-fold rotational symmetry is disrupted while translational symmetry is maintained. Further application of an external magnetic field demonstrates a strong coupling of the YMn6Sn6 kagome band to the field, which exhibits an energy shift discrepancy under different field directions, implying the existence of magnetization-response anisotropy and anomalous g factors. Our findings establish YMn6Sn6 as an ideal platform for investigating kagome-derived orbital magnetic moment and correlated magnetic topological states.

4.
Nano Lett ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007862

RESUMO

The coexistence of superconductivity and ferromagnetism is an intrinsically interesting research focus in condensed matter physics, but the study is limited by low superconducting (Tc) and magnetic (Tm) transition temperatures in related materials. Here, we used a scanning superconducting quantum interference device to image the in situ diamagnetic and ferromagnetic responses of RbEuFe4As4 with high Tc and Tm. We observed significant suppression of the superfluid density in the vicinity of the magnetic phase transition, signifying fluctuation-enhanced magnetic scatterings between Eu spins and Fe 3d conduction electrons. Intriguingly, we observed multiple ferromagnetic domains that should be absent in an ideal magnetic helical phase. The formation of these domains demonstrates a weak c-axis ferromagnetic component probably arising from the Eu spin-canting effect, indicative of possible superconductivity-driven domain Meissner and domain vortex-antivortex phases, as revealed in EuFe2(As0.79P0.21)2. Our observations highlight that RbEuFe4As4 is a unique system that includes multiple interplay channels between superconductivity and ferromagnetism.

5.
Nano Lett ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38991547

RESUMO

The interpretation of mechanisms governing hot carrier reactivity on metallic nanostructures is critical, yet elusive, for advancing plasmonic photocatalysis. In this work, we explored the influence of the diffusion of molecules on the hot carrier extraction rate at the solid-liquid interface, which is of fundamental interest for increasing the efficiency of photodevices. Through a spatially defined scanning photoelectrochemical microscopy investigation, we identified a diffusion-controlled regime hindering the plasmon-driven photochemical activity of metallic nanostructures. Using low-power monochromatic illumination (<2 W cm-2), we unveiled the hidden influence of mass transport on the quantum efficiency of plasmonic photocatalysts. The availability of molecules at the solid-liquid interface directly limits the extraction of hot holes, according to their nature and energy, at the reactive spots in Au nanoislands on an ultrathin TiO2 substrate. An intriguing question arises: does the mass transport enhancement caused by thermal effects unlock the reactivity of nonthermal carriers under steady state?

6.
J Hazard Mater ; 476: 135054, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38991647

RESUMO

Microplastics (MPs) is an emerging pollutant potentially harmful to health. Medical practices using plastic devices, such as percutaneous coronary interventions (PCI), may result in MPs entering into the blood. The purpose of this study was to quantify the effect of PCI on microplastic levels in patients' blood. Laser direct infrared (LDIR) was used to detect MPs in the blood of 23 patients before and after PCI. MPs in the water in which devices used in PCI were washed were also examined. The concentration of MPs in the blood was significantly elevated (93.57 ± 35.95 vs. 4.96 ± 3.40 particles/10 mL of blood, P < 0.001) after PCI compared to before, and the increased MPs were polyamide (PA), polyethylene (PE), polyurethane (PU), and polyethylene terephthalate (PET), which was consistent with the types of MPs detected in the device washing water. The maximum diameter of MPs in blood before PCI was 50 µm, whereas after PCI it was 213 µm, and even 336 µm in device washing water. These findings indicated that PCI will cause MPs to enter the blood, and devices used during PCI were a major source, a range of medical practices that use plastic devices may be a new route for MPs to enter the human body.

7.
BMC Vet Res ; 20(1): 310, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992617

RESUMO

The present investigation examined the oropharyngeal roof of two turtles having different feeding behaviors: the landform Greek tortoise (Testudo graeca graeca) primarily herbivores and the semi-aquatic red-eared slider turtle (Trachemys scripta elegans) lives in freshwater that opportunistic omnivorous grossly and by scanning and light microscopes. Grossly, the Greek tortoise had a V-shaped roof consisting of the upper rhamphotheca, peri-palatine region, upper alveolar ridge, peripheral palatine ridge, median palatine ridge, vomer, choanae, caudal palatine part, and pharynx. At the same time, the red-eared slider had a semilunar roof consisting of upper rhamphotheca, two peripheral palatine ridges, core of palatine ridges, upper alveolar band, vomer, choanae, caudal palatine part, and pharynx. SEM revealed that the red-eared slider roof appeared more straightforward. The upper rhamphotheca is sharp, with a median premaxillary notch in the red-eared slider that gives a powerful bite for cutting to compensate absence of the teeth. Additionally, the red-eared slider's upper alveolar band is interrupted by a single upper alveolar ridge that appears spiky, pointed, and longer as it needs powerful chewing of prey and there are two types of teeth-like projections at its peri-palatine area for food-crushing and chewing. The Greek tortoise palatine region had numerous ridges and folds to provide roughness for food processing. Greek tortoises had small-sized choanae with two choanal folds to minimize choanal openings when eating dusty grasses. Histologically, Greek tortoise palate was rostrally thicker and more keratinized than caudally, and the caudal palatine region was characterized by a single pair of circumvallate-like papilla with multiple mucous openings and secretions, while red-eared slider palate was slightly keratinized at the peri-choanal region, and the rest of the palate was non-keratinized with few mucous openings. The current investigation found various structural oropharyngeal roof adaptations to feeding behavior in the omnivore red-eared slide compared to the herbivorous Greek turtle.


Assuntos
Comportamento Alimentar , Orofaringe , Tartarugas , Animais , Tartarugas/anatomia & histologia , Orofaringe/anatomia & histologia , Microscopia Eletrônica de Varredura/veterinária
9.
Autism Res ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38993038

RESUMO

In autistic individuals, the role, performance, and autonomy of perceptual functioning are atypical. Overlapping underlying mechanisms of perception and mental imagery predict that the mental imagery abilities of autistic individuals should differ from those of non­autistic individuals. While enhanced abilities to manipulate mental images have been demonstrated in autism, the other stages of mental imagery (generation, maintenance, inspection) remain to be explored. Forty­four autistic adults and 42 typical participants performed four tasks to assess different stages of mental imagery: the Image generation task (mentally generating a letter on a grid and indicating whether it passes over a probe located in the grid), the Visual pattern test (maintaining visual patterns in memory), the Image scanning test (inspecting mental images) and the Mental rotation test (mentally manipulating representations of geometric figures). In the image generation task and the mental rotation test, autistic and typical individuals performed equivalently, both in accuracy and response time. The span observed in the visual pattern test was significantly higher in the autistic group, indicating better maintenance of mental images. In the image scanning test, response times were influenced by the distance to mentally inspect in the typical group but not in the autistic group. Autistic participants were equally fast regardless of distance to inspect. Preserved, greater or differently influenced visual mental imagery abilities are in line with an atypical perceptual functioning in autism, possibly reflecting an increased weight of perception­based information relatively to the top­down effect of knowledge and language­based influence.

10.
Microsc Microanal ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38993166

RESUMO

We report application of the knife-edge technique at the sharp edges of WS2 and MoS2 monolayer flakes for lateral and axial resolution assessment in all three modalities of nonlinear laser scanning microscopy: two-photon excited fluorescence (TPEF), second- and third-harmonic generation (SHG, THG) imaging. This technique provides a high signal-to-noise ratio, no photobleaching effect and shows good agreement with standard resolution measurement techniques. Furthermore, we assessed both the lateral resolution in TPEF imaging modality and the axial resolution in SHG and THG imaging modality directly via the full-width at half maximum parameter of the corresponding Gaussian distribution. We comprehensively analyzed the factors influencing the resolution, such as the numerical aperture, the excitation wavelength and the refractive index of the embedding medium for the different imaging modalities. Glycerin was identified as the optimal embedding medium for achieving resolutions closest to the theoretical limit. The proposed use of WS2 and MoS2 monolayer flakes emerged as promising tools for characterization of nonlinear imaging systems.

11.
ACS Nano ; 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38946088

RESUMO

The honeycomb lattice is a fundamental two-dimensional (2D) network that gives rise to surprisingly rich electronic properties. While its expansion to 2D supramolecular assembly is conceptually appealing, its realization is not straightforward because of weak intermolecular coupling and the strong influence of a supporting substrate. Here, we show that the application of a triptycene derivative with phenazine moieties, Trip-Phz, solves this problem due to its strong intermolecular π-π pancake bonding and nonplanar geometry. Our scanning tunneling microscopy (STM) measurements demonstrate that Trip-Phz molecules self-assemble on a Ag(111) surface to form chiral and commensurate honeycomb lattices. Electronically, the network can be viewed as a hybrid of honeycomb and kagome lattices. The Dirac and flat bands predicted by a simple tight-binding model are reproduced by total density functional theory (DFT) calculations, highlighting the protection of the molecular bands from the Ag(111) substrate. The present work offers a rational route for creating chiral 2D supramolecules that can simultaneously accommodate pristine Dirac and flat bands.

12.
Aust Endod J ; 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38946230

RESUMO

The aim was to analyse the influence of an apical ledge on root canal disinfection. Forty-four single-rooted teeth were micro-CT scanned and inoculated with Enterococcus faecalis. In Group S shaping was performed with ProTaper Next (PTN) up to X3 at working length (WL). In Group L an apical ledge was created with K-Files #40 and shaping completed up to PTN X3. NaOCl 5% and EDTA 10% irrigant solutions were alternated. Confocal laser scanning microscope (CLSM) and viability staining were used to analyse the proportions of dead (red) and live (green) bacteria and penetration ability inside dentinal tubules. Data were analysed with the Mann-Whitney test with Bonferroni correction (p < 0.05). In Group L the amount of red fluorescence resulted significantly lower, and penetration ability was decreased in the apical and middle portion (p < 0.05). The presence of an apical ledge may negatively influence the disinfection both in the apical and middle third.

13.
Med Phys ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949569

RESUMO

BACKGROUND: MR-integrated proton therapy is under development. It consists of the unique challenge of integrating a proton pencil beam scanning (PBS) beam line nozzle with an magnetic resonance imaging (MRI) scanner. The magnetic interaction between these two components is deemed high risk as the MR images can be degraded if there is cross-talk during beam delivery and image acquisition. PURPOSE: To create and benchmark a self-consistent proton PBS nozzle model for empowering the next stages of MR-integrated proton therapy development, namely exploring and de-risking complete integrated prototype system designs including magnetic shielding of the PBS nozzle. MATERIALS AND METHODS: Magnetic field (COMSOL Multiphysics ${\text{Multiphysics}}$ ) and radiation transport (Geant4) models of a proton PBS nozzle located at OncoRay (Dresden, Germany) were developed according to the manufacturers specifications. Geant4 simulations of the PBS process were performed by using magnetic field data generated by the COMSOL Multiphysics ${\text{Multiphysics}}$ simulations. In total 315 spots were simulated which consisted of a 40 × 30 cm 2 $40\times 30\,{\text{cm}}^{2}$ scan pattern with 5 cm spot spacings and for proton energies of 70, 100, 150, 200, and 220 MeV. Analysis of the simulated deflection at the beam isocenter plane was performed to determine the self-consistency of the model. The magnetic fringe field from a sub selection of 24 of the 315 spot simulations were directly compared with high precision magnetometer measurements. These focused on the maximum scanning setting of ± $\pm$  20 cm beam deflection as generated from the second scanning magnet in the PBS for a proton beam energy of 220 MeV. Locations along the beam line central axis (CAX) were measured at beam isocenter and downstream of 22, 47, 72, 97, and 122 cm. Horizontal off-axis positions were measured at 22 cm downstream of isocenter ( ± $\pm$  50, ± $\pm$  100, and ± $\pm$  150 cm from CAX). RESULTS: The proton PBS simulations had good spatial agreement to the theoretical values in all 315 spots examined at the beam line isocenter plane (0-2.9 mm differences or within 1.5 % of the local spot deflection amount). Careful analysis of the experimental measurements were able to isolate the changes in magnetic fields due solely to the scanning magnet contribution, and showed 1.9  ± $\pm$  1.2 µ T $\bf{\mu} {\text{T}}$ -9.4 ± $\pm$  1.2 µ T $\bf{\mu} {\text{T}}$ changes over the range of measurement locations. Direct comparison with the equivalent simulations matched within the measurement apparatus and setup uncertainty in all but one measurement point. CONCLUSIONS: For the first time a robust, accurate and self-consistent model of a proton PBS nozzle assembly has been created and successfully benchmarked for the purposes of advancing MR-integrated proton therapy research. The model will enable confidence in further simulation based work on fully integrated designs including MRI scanners and PBS nozzle magnetic shielding in order to de-risk and realize the full potential of MR-integrated proton therapy.

14.
Vestn Oftalmol ; 140(3): 34-42, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38962977

RESUMO

Standard bacteriological examinations, which involve culturing microorganisms at 37 °C, are commonly used in clinical practice for diagnosing infectious diseases. However, the growth temperature of microorganisms on the ocular surface (OS) during infectious keratitis (IK) may not coincide with the laboratory standard, which is due to the characteristic features of heat exchange in the eye. PURPOSE: This exploratory study examines the distribution and properties of OS microorganisms isolated under different temperature cultivation conditions in patients with IK and healthy volunteers without ophthalmic pathology. MATERIAL AND METHODS: Fifteen participants were divided into two groups. Group 1 (n=10) consisted of patients with signs of unilateral infectious keratitis, while group 2 (n=5) served as the control group. A novel microbiological method was employed to isolate pure cultures of microorganisms. This method involved cultivating microorganisms at two temperature regimes (37 °C and 24 °C) and subsequently identifying them using biochemical, immunological, and physicochemical techniques, including mass spectrometry. Scanning electron microscopy (SEM) with lanthanide staining used as the reference method. The temperature status of the ocular surface was assessed using non-contact infrared thermography. RESULTS: The study demonstrated the presence of psychrotolerant microorganisms on the ocular surface, which exhibited growth at a relatively low temperature of 24 °C. These psychrotolerant microorganisms were found to be isolated from the ocular surface displaying signs of temperature dysregulation. Among such microorganisms are Acinetobacter lwoffii, Achromobacter xylosoxidans, Bacillus licheniformis, Enterococcus faecalis, Klebsiella oxytoca, Klebsiella pneumoniae, Micrococcus luteus, Pseudomonas luteola, Streptococcus spp. CONCLUSION: When identifying the causative agent of infectious keratitis, it is crucial to consider the divergence of growth temperature of ocular surface microorganisms. The presence of psychrotolerant microorganisms on the ocular surface, which can effectively grow at room temperature, should be taken into account, especially in cases of temperature dysregulation.


Assuntos
Infecções Oculares Bacterianas , Ceratite , Humanos , Ceratite/microbiologia , Ceratite/diagnóstico , Masculino , Feminino , Infecções Oculares Bacterianas/microbiologia , Infecções Oculares Bacterianas/diagnóstico , Adulto , Pessoa de Meia-Idade , Temperatura , Córnea/microbiologia , Termografia/métodos
15.
Small ; : e2402976, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963321

RESUMO

Morphology, crystal phase, and its transformation are important structures that frequently determine electrocatalytic activity, but the correlations of intrinsic activity with them are not completely understood. Herein, using Co(OH)2 micro-platelets with well-defined structures (phase, thickness, area, and volume) as model electrocatalysts of oxygen evolution reaction, multiple in situ microscopy is combined to correlate the electrocatalytic activity with morphology, phase, and its transformation. Single-entity morphology and electrochemistry characterized by atomic force microscopy and scanning electrochemical cell microscopy reveal a thickness-dependent turnover frequency (TOF) of α-Co(OH)2. The TOF (≈9.5 s-1) of α-Co(OH)2 with ≈14 nm thickness is ≈95-fold higher than that (≈0.1 s-1) with ≈80 nm. Moreover, this thickness-dependent activity has a critical thickness of ≈30 nm, above which no thickness-dependence is observed. Contrarily, ß-Co(OH)2 reveals a lower TOF (≈0.1 s-1) having no significant correlation with thickness. Combining single-entity electrochemistry with in situ Raman microspectroscopy, this thickness-dependent activity is explained by more reversible Co3+/Co2+ kinetics and larger ratio of active Co sites of thinner α-Co(OH)2, accompanied with faster phase transformation and more extensive surface restructuration. The findings highlight the interactions among thickness, ratio of active sites, kinetics of active sites, and phase transformation, and offer new insights into structure-activity relationships at single-entity level.

16.
BMC Bioinformatics ; 25(1): 229, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956474

RESUMO

Adeno-associated viruses 2 (AAV2) are minute viruses renowned for their capacity to infect human cells and akin organisms. They have recently emerged as prominent candidates in the field of gene therapy, primarily attributed to their inherent non-pathogenic nature in humans and the safety associated with their manipulation. The efficacy of AAV2 as gene therapy vectors hinges on their ability to infiltrate host cells, a phenomenon reliant on their competence to construct a capsid capable of breaching the nucleus of the target cell. To enhance their infection potential, researchers have extensively scrutinized various combinatorial libraries by introducing mutations into the capsid, aiming to boost their effectiveness. The emergence of high-throughput experimental techniques, like deep mutational scanning (DMS), has made it feasible to experimentally assess the fitness of these libraries for their intended purpose. Notably, machine learning is starting to demonstrate its potential in addressing predictions within the mutational landscape from sequence data. In this context, we introduce a biophysically-inspired model designed to predict the viability of genetic variants in DMS experiments. This model is tailored to a specific segment of the CAP region within AAV2's capsid protein. To evaluate its effectiveness, we conduct model training with diverse datasets, each tailored to explore different aspects of the mutational landscape influenced by the selection process. Our assessment of the biophysical model centers on two primary objectives: (i) providing quantitative forecasts for the log-selectivity of variants and (ii) deploying it as a binary classifier to categorize sequences into viable and non-viable classes.


Assuntos
Mutação , Humanos , Proteínas do Capsídeo/genética , Dependovirus/genética , Parvovirinae/genética
17.
Anat Rec (Hoboken) ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38982846

RESUMO

Herein, we revise the material of the extinct taxon Pseudopus pannonicus from Central Europe, the largest known anguid lizard and iconic member of herpetofaunas from the Upper Cenozoic of Europe. The geographical position of Polgárdi 2, the type locality of P. pannonicus, as well as several other closely located important localities make Central Europe a valuable area of high interest for studies regarding European Cenozoic palaeoherpetological assemblages. We clarified the nature of the type material of Pseudopus pannonicus, showing that it consisted not only of the five specimens originally figured. Instead, the syntype series also includes a considerable number of specimens from Polgárdi 2 that were only described or figured 12 years after the original description of P. pannonicus. Detailed osteological descriptions are provided for specimens from the type series and Polish specimens, with the aid of high-resolution imaging (SEM and µCT scanning), and intraspecific variability is discussed. The articular surface with the lappet of the parietal overlapping the frontal is discussed as a character potentially relevant for the diagnosis of P. pannonicus. We updated the identification of several specimens of P. pannonicus and discussed the biogeographic implications of such revisions. In Poland, P. pannonicus is an abundant component of Neogene and early Quaternary herpetofaunas, known with certainty from the Middle Miocene of Przeworno (the oldest known occurrence of the species globally), the Early-Late Pliocene of Weze I, the Late Pliocene of Rebielice Królewskie I, the Late Pliocene of Weze II, and the Early Pleistocene of Kadzielnia (one of the youngest occurrences documented globally). An indeterminate anguine with Anguis affinities is newly reported from Rebielice Królewskie II. The taxonomic status of other large anguids from the Neogene of Europe is discussed and we conclude that most are junior synonyms of P. pannonicus. We also show that another purported synonym, that is, Ophisaurus intermedius from the Early Pleistocene of Romania, is instead a nomen nudum. We conducted phylogenetic analyses (18 taxa, 65 characters) to understand the relationship of P. pannonicus relative to other anguid representatives and anguid-related group (i.e., glyptosaurids). A single most parsimonious tree (length: 134 steps) was recovered. The clade Pseudopus is stable, comprising the two distinct sister subclades [Pseudopus laurillardi + Pseudopus ahnikoviensis] and [Pseudopus pannonicus + Pseudopus apodus]. These phylogenetic results are in accordance with previously published works.

18.
Small ; : e2402260, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38982949

RESUMO

The metal-insulator (MI) transition of vanadium dioxide (VO2) is effectively modulated by oxygen vacancies, which decrease the transition temperature and insulating resistance. Oxygen vacancies in thin films can be driven by oxygen transport using electrochemical potential. This study delves into the role of crystallographic channels in VO2 in facilitating oxygen transport and the subsequent tuning of electrical properties. A model system is designed with two types of VO2 thin films: (100)- and (001)-oriented, where channels align parallel and perpendicular to the surface, respectively. Growing an oxygen-deficient TiO2 layer on these VO2 films prompted oxygen transport from VO2 to TiO2. Notably, in (001)-VO2 film, where oxygen ions move along the open channels, the oxygen migration deepens the depleted region beyond that in (100)-VO2, leading to more pronounced changes in metal-insulator transition behaviors. The findings emphasize the importance of understanding the intrinsic crystal structure, such as channel pathways, in controlling ionic defects and customizing electrical properties for applications.

19.
J Pathol ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984400

RESUMO

Whole slide imaging (WSI) of pathology glass slides using high-resolution scanners has enabled the large-scale application of artificial intelligence (AI) in pathology, to support the detection and diagnosis of disease, potentially increasing efficiency and accuracy in tissue diagnosis. Despite the promise of AI, it has limitations. 'Brittleness' or sensitivity to variation in inputs necessitates that large amounts of data are used for training. AI is often trained on data from different scanners but not usually by replicating the same slide across scanners. The utilisation of multiple WSI instruments to produce digital replicas of the same slides will make more comprehensive datasets and may improve the robustness and generalisability of AI algorithms as well as reduce the overall data requirements of AI training. To this end, the National Pathology Imaging Cooperative (NPIC) has built the AI FORGE (Facilitating Opportunities for Robust Generalisable data Emulation), a unique multi-scanner facility embedded in a clinical site in the NHS to (1) compare scanner performance, (2) replicate digital pathology image datasets across WSI systems, and (3) support the evaluation of clinical AI algorithms. The NPIC AI FORGE currently comprises 15 scanners from nine manufacturers. It can generate approximately 4,000 WSI images per day (approximately 7 TB of image data). This paper describes the process followed to plan and build such a facility. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38984990

RESUMO

The urgent challenges posed by the energy crisis, alongside the heat dissipation of advanced electronics, have embarked on a rising demand for the development of highly thermally conductive polymer composites. Electrospun composite mats, known for their flexibility, permeability, high concentration and orientational degree of conductive fillers, stand out as one of the prime candidates for addressing this need. This study explores the efficacy of boron nitride (BN) and its potential alternative, silicon nitride (SiN) nanoparticles, in enhancing the thermal performance of the electrospun composite thermoplastic polyurethane (TPU) fibers and mats. The 3D reconstructed models obtained from FIB-SEM imaging provided valuable insights into the morphology of the composite fibers, aiding the interpretation of the measured thermal performance through scanning thermal microscopy for the individual composite fibers and infrared thermography for the composite mats. Notably, we found that TPU-SiN fibers exhibit superior heat conduction compared to TPU-BN fibers, with up to a 6 °C higher surface temperature observed in mats coated on copper pipes. Our results underscore the crucial role of arrangement of nanoparticles and fiber morphology in improving heat conduction in the electrospun composites. Moreover, SiN nanoparticles are introduced as a more suitable filler for heat conduction enhancement of electrospun TPU fibers and mats, suggesting immense potential for smart textiles and thermal management applications.

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