Browse Articles

Reversible long-range domain wall motion in an improper ferroelectric

Abstract Reversible ferroelectric domain wall movements beyond the 10 nm range associated with Rayleigh behavior are usually restricted to specific defect-engineered systems. Here, we demonstrate that such long-range movements naturally occur in the improper ferroelectric ErMnO3 during electric-field-cycling. We study the electric-field-driven motion of domain walls, showing that they readily return to their initial position after having traveled distances exceeding 250 nm. By applying switching spectroscopy band-excitation piezoresponse force microscopy, we track the domain wall movement with nanometric spatial precision and analyze the local switching behavior. Phase field simulations show that the reversible long-range motion is intrinsic to the hexagonal manganites, linking it to their improper ferroelectricity and topologically protected structural vortex lines, which serve as anchor point for the ferroelectric domain walls. Our results give new insight into the local dynamics of domain walls in improper ferroelectrics and demonstrate the possibility to reversibly displace domain walls over much larger distances than commonly expected for ferroelectric systems in their pristine state, ensuring predictable device behavior for applications such as tunable capacitors or sensors.

Insights into leprosy epidemiology from an isolated population located in the Brazilian Amazon

Abstract Leprosy, a chronic infectious disease caused mainly by Mycobacterium leprae ( M. leprae ), is still an important public health problem in countries such as Brazil and India. Here, we estimate key epidemiological parameters in the Prata Village, a unique, hyper-endemic, former leprosy colony isolated in the Brazilian Amazon. This is a population-based study in which the entire Prata Village population has been enrolled. Clinical, socioeconomic, and demographic data were obtained and validated by cross-checking using three independent information sources. Validated data was used for descriptive epidemiological analysis. From a total of 2,005 inhabitants by the time of the enrollment, 1,084 (56.2%) were born in the Village and, therefore, likely under lifelong exposure to leprosy cases. We observed differences between the sub-populations born and not born in the village in the cumulative prevalence of leprosy (5.9% vs. 22.9%, respectively) and the median age at diagnosis (15 years vs. 28 years, respectively). In contrast, there was no difference in the distribution of cases between males and females. Although extrapolating our findings to more open populations must be done carefully, we believe we used a unique population as a model to provide additional insights into the epidemiology of leprosy.

Designed Synthesis of Covalent Organic Multicycles

Bias in data-driven replicability analysis of univariate brain-wide association studies

Abstract Recent studies have used big neuroimaging datasets to answer an important question: how many subjects are required for reproducible brain-wide association studies? These data-driven approaches could be considered a framework for testing the reproducibility of several neuroimaging models and measures. Here we test part of this framework, namely estimates of statistical errors of univariate brain-behaviour associations obtained from resampling large datasets with replacement. We demonstrate that reported estimates of statistical errors are largely a consequence of bias introduced by random effects when sampling with replacement close to the full sample size. We show that future meta-analyses can largely avoid these biases by only resampling up to 10% of the full sample size. We discuss implications that reproducing mass-univariate association studies requires tens-of-thousands of participants, urging researchers to adopt other methodological approaches.

Lattice Oxygen-Driven Co-Adsorption of Carbon Dioxide and Nitrate on Copper: A Pathway to Efficient Urea Electrosynthesis

Coupling flux balance analysis with reactive transport modeling through machine learning for rapid and stable simulation of microbial metabolic switching

Stereoselective Chemoenzymatic Cascades for the Synthesis of Densely Functionalized Iminosugars

Paraben exposure related to Staphylococcal enterotoxin IgE sensitization, allergic rhinitis and nasal patency in children

Red-Light-Active <i>N,C,N-</i> Pincer Bismuthinidene: Excited State Dynamics and Mechanism of Oxidative Addition into Aryl Iodides

Association between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio and hand grip strength in U.S. adults

Activation of Electrophilic Reactivity by Protonation and Oxidation of a Peroxo Co^IIICo^III Complex: Reactivity and Molecular Structures of Hydroperoxo, Superoxo, and Peroxo Co^IIICo^III Complexes

Premature ageing of lung alveoli and bone marrow cells from Terc deficient mice with different telomere lengths

Abstract Telomeres are terminal protective chromosome structures. Genetic variants in genes coding for proteins required for telomere maintenance cause rare, life-threatening Telomere Biology Disorders (TBDs) such as dyskeratosis congenita, aplastic anemia or pulmonary fibrosis. The more frequently used mice strains have telomeres much longer than the human ones which question their use as in vivo models for TBDs. One mice model with shorter telomeres based on the CAST/EiJ mouse strain carrying a mutation in the Terc gene, coding for the telomerase RNA component, has been studied in comparison with C57BL/6J mice, carrying the same mutation and long telomeres. The possible alterations produced in lungs and the haematopoietic system, frequently affected in TBD patients, were determined at different ages of the mice. Homozygous mutant mice presented a very shortened life span, more notorious in the short-telomeres CAST/EiJ strain. The lungs of mutant mice presented a transitory increase in fibrosis and a significant decrease in the relative amount of the alveolar epithelial type 2 cells from six months of age. This decrease was larger in mutant homozygous animals but was also observed in heterozygous animals. On the contrary the expression of the senescence-related protein P21 increased from six months of age in mutant mice of both strains. The analysis of the haematopoietic system indicated a decrease in the number of megakaryocyte-erythroid progenitors in homozygous mutants and an increase in the clonogenic potential of bone marrow and LSK cells. Bone marrow cells from homozygous mutant animals presented decreasing in vitro expansion capacity. The alterations observed are compatible with precocious ageing of lung alveolar cells and the bone marrow cells that correlate with the alterations observed in TBD patients. The alterations seem to be more related to the genotype of the animals that to the basal telomere length of the strains although they are more pronounced in the short-telomere CAST/EiJ-derived strain than in C57BL/6J animals. Therefore, both animal models, at ages over 6–8 months, could represent valuable and convenient models for the study of TBDs and for the assay of new therapeutic products.

Catalysis of Free C–C Bond Rotation: C–F---H–X H-Bonds Find a Catalytic Role

Identification and validation of PANoptosis-related LncRNAs prognosis system in hepatocellular carcinoma

Abstract Hepatocellular carcinoma (HCC) is one of the most common solid malignancies in the world. Due to the limited effectiveness of current drug treatments, further research on HCC is necessary. PANoptosis is defined as an inflammatory RCD whose main features combine pyroptosis, apoptosis and necroptosis which cannot be explained by any of these three RCDs alone. In HCC, risk stratification based on PANoptosis-associated lncRNAs has clinical application potential. In this study, we explored HCC related PANoptosis-related lncRNAs (PRLs) by analyzing significantly differentially expressed genes in HCC. HCC-associated PRL scores were established by WGCNA, LASSO analysis and multivariate Cox assessment. Subsequently, we verified the prognostic analysis ability of PRL score for HCC patients, and on this basis established a prognostic risk assessment model for HCC and verified its reliability. The relationship between PRL score and immune infiltration as well as drug sensitivity was further analyzed to evaluate the clinical reference value of this model. Western blot analysis and PCR further verified the reliability of bioinformatics results. The observed suppression of HCC progression and invasiveness following selected PRL knockdown further validated the reliability of our bioinformatics analysis results. Our results provide new evidence for the role of PANoptosis-associated lncRNAs in HCC.

Why Do Weak-Binding M–N–C Single-Atom Catalysts Possess Anomalously High Oxygen Reduction Activity?

Mastitis-related Staphylococcus aureus-derived extracellular vesicles induce a pro-inflammatory response in bovine monocyte-derived macrophages

Abstract Staphylococcus aureus (S. aureus) is one of the most common causative agents of mammary gland infection and mastitis, but the specific role of S. aureus-derived extracellular vesicles (SaEVs) in mastitis has been poorly studied to date. Here, we aimed to investigate the response of bovine monocyte-derived macrophages (boMdM) to SaEVs of the genotype B (GTB) mastitis-related strain M5512B. Specifically, we evaluated the effects on the actin cytoskeleton, gene expression, and the SaEV proteomic cargo. Furthermore, we assessed to what extent the cellular and molecular response of boMdM to SaEVs differed from peripheral mononuclear blood cells (PBMCs) used for in vitro derivation of the former. We observed that SaEVs induced morphological changes in boMdM, leading to a pro-inflammatory and pyroptosis-related increased gene expression. Additionally, our study revealed that boMdM and PBMCs exhibited stimulus-specific differing responses. The proteomic analysis of SaEVs identified clusters of proteins related to virulence and antibiotic resistance, supporting the theory that S. aureus might use EVs to evade host defences and colonize the mammary gland. Our results bring new insights into how SaEVs might impact the host during an S. aureus infection, which can be useful for future S. aureus vaccine development.

In-Situ Thermometry Reveals Fragmentation Behavior Based on Local Temperature in α-Olefin Polymerization Catalysts

Titania nanotubes with aminated reduced graphene oxide as efficient photocatalysts for antibacterial application under visible light

Low-Temperature Exsolution of Rh from Mixed ZnFeRh Oxides toward Stable and Selective Catalysts in Liquid-Phase Hydroformylation

Numerical and machine learning based evaluation of ethylene glycol based hybrid nano-structured (TiO2-SWCNTs) fluid flow