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The mechanical distribution of the mandible is an important factor that affects functional orthosis during Twin-block (TB) appliance correction. Changes in the mandible before and after TB appliance correction are also key factors in maintaining the therapeutic effect. Finite element analysis, a powerful numerical, analytical tool, is widely used to predict the stress and strain distribution of the craniofacial bone that orthodontics generates. The sample was a 14-year-old male patient with Class II malocclusion during growth. A cone-beam computed tomography scan was undertaken at pretreatment and posttreatment. In the Finite element analysis of the pretreatment model, the remote displacement model of the mandible was established with the sella point as the center. A mandibular model under TB appliance loading was established. Its mandibular displacement and von Mises stress were compared before and after loading. Three-dimensional registration was conducted on the pretreatment and posttreatment models to measure the sagittal displacement of the centrosome. The force on the mandible occurred mainly in the condyle neck and medial mandible after the TB appliance moved the mandible. After displacement, the posterior upper margin of the condyle was farther away from the articular fossa. Three-dimensional registration results showed that new bone had formed behind and above the condyle after TB appliance treatment. The TB appliance provides additional advantages in treating skeletal Class II malocclusions by helping to reduce the burden on the temporomandibular joint and promoting the adaptive reconstruction of the mandible. • A new understanding of the clinical effect of Twin-block appliance was put forward. • Clinical use of Twin-block appliance can reduce temporomandibular joint burden and promote joint remodeling. • A new finite element analysis method, the remote displacement model, was examined. • The force on mandible of TB appliance was explained by finite element analysis. [ABSTRACT FROM AUTHOR]

Ester-containing deltamethrin pesticides are widely used in farmland and have inevitable side effects on the biosphere and human health. Microbia have been used for efficient degradation of deltamethrin, but the related mechanism and enzyme characteristics have not been elucidated. In this study, a species Brevibacillus parabrevis BCP-09 could degrade up to 75 mg L−1 deltamethrin with a degradation efficiency of 95.41%. Proteomic and genomic methods were used to explore its degradation mechanism. Enzymes belonged to hydrolases, oxidases and aromatic compound degrading enzymes were expressed enhanced and might participate in the deltamethrin degradtion. RT-PCR experiment and enzyme activity analysis verified the degradation of deltamethrin by bacterial protein. Additionally, the formation of endospores can help strain BCP-09 resist the toxicity of deltamethrin and enhance its degradation. This study supplies a scientific evidence for the application of Brevibacillus parabrevis BCP-09 in the bioremediation of environmental pollution and enriches the resources of deltamethrin-biodegradable proteins. [Display omitted] • Brevibacillus parabrevis BCP-09 could degrade 75 mg L−1 deltamethrin within 96 h. • The degradation mechanism was analyzed based on proteomics results. • Enzymes involved in the degradation of deltamethrin were identified. • The endospores produced by strain BCP-09 enhance its resistance to deltamethrin. [ABSTRACT FROM AUTHOR]

Highlights • A multi-IAC-HPLC method for simultaneously detecting 9 Fusarium mycotoxins was established. • Whole wheat flour has higher mycotoxins concentrations compared to refined wheat flour. • Cumulative health risks caused by Fusarium mycotoxins and their derivatives should be concerned. Abstract Multiple mycotoxins can contaminate foods simultaneously leading to increased risks for human health. To assess exposure and health risks of 9 mycotoxins, we employed a multiple immunoaffinity column – high performance liquid chromatography method to determine their concentrations of 35 whole wheat flour and 50 refined wheat flour samples from China. The recoveries of the validated method were 75.78–118.24%, and the limits of detection and quantification were 1.5–20 and 5.0–60 µg kg−1, respectively. Multiple mycotoxins were detected in 37.1% of whole wheat flour and 8% of refined wheat flour. In the worst-case scenario, the hazard index was 222.69% for male and 253.97% for female with a cumulative exposure to Fusarium mycotoxins through consuming whole wheat flour, and deoxynivalenol was the main mycotoxin detected. In conclusion, whole wheat flour should be regarded with more health concern because of cumulative effects of co-occurred mycotoxins. [ABSTRACT FROM AUTHOR]

Organic friction modifiers (FMs) are commonly utilized in lubricants. FM molecules possess a polar head group that interacts with metallic surfaces and aliphatic chains that cohesively interact with neighboring molecules. Under boundary lubrication conditions, as experienced in engine valve trains and cylinders, fluid films are unable to form between metallic surfaces. This results in metal-metal contact. Thus, organic friction modifiers are commonly utilized to reduce friction under these conditions. While efficacious, these molecules are consumed over time owing to engine environments, reducing their effectiveness. To replenish organic friction modifier stocks in base oil lubricants, tertiary ester derivatives of fatty acid-containing dicarboxylic acids were investigated. A series of fatty acid-containing dicarboxylic acids were first developed based on a tartaric acid backbone and their friction modifying capabilities assessed. Coefficient of friction studies illustrated that friction-modifying capabilities were heavily influenced by polar head group type (i.e., carboxylic acid, ester) and chemical bond to tartaric acid (i.e., ester, ether). Thermogravimetric analysis coupled gas-phase Fourier transform infrared spectroscopy revealed that fatty acid-containing dicarboxylic acids degraded into their respective fatty acids at elevated temperatures. Controlled release studies were conducted on a compound modified with thermocleavable esters, and showed sustained friction modifying activity through the course of the entire study. These systems are ideal candidates for the controlled delivery of friction modifiers, which can increase engine efficiency and reduce fuel consumption, effectively reducing vehicle emissions. [ABSTRACT FROM AUTHOR]

Inspired by high promise using naturally occurring antimicrobial peptides (AMPs) to treat infections caused by antimicrobial-resistant bacteria, cationic amphiphiles (CAms) were strategically designed as synthetic mimics to overcome associated limitations, including high manufacture cost and low metabolic stability. CAms with facially amphiphilic conformation were expected to demonstrate membrane-lytic properties and thus reduce tendency of resistance development. By systematically tuning the hydrophobicity, CAms with optimized compositions exhibited potent broad-spectrum antimicrobial activity (with minimum inhibitory concentrations in low μg/mL range) as well as negligible hemolytic activity. Electron microscope images revealed the morphological and ultrastructure changes of bacterial membranes induced by CAm treatment and validated their membrane-disrupting mechanism. Additionally, an all-atom molecular dynamics simulation was employed to understand the CAm-membrane interaction on molecular level. This study shows that these CAms can serve as viable scaffolds for designing next generation of AMP mimics as antimicrobial alternatives to combat drug-resistant pathogens. [ABSTRACT FROM AUTHOR]

Dibutyl phthalate (DBP) is widely used as a plasticizer in plastic food packaging and has attracted extensive attention due to its residual hazards and ability to accumulate. Microbial degradation is a very effective way to remove DBP from a polluted environment. In this study, Stenotrophomonas acidaminiphila BDBP 071, a strain that efficiently degraded DBP was isolated from tomato rhizosphere soil. To obtain a comprehensive understanding of the degradation mechanism of DBP by S. acidaminiphila strain BDBP 071, whole genome sequencing of this strain was performed. The results showed that the genome size of BDBP 071 was 3.87 Mb, the G + C content was 69.43%, and the number of predicted coding sequences was 3484. Based on whole genome sequencing, the metabolic pathway related to DBP biotransformation was obtained, and key genes were subsequently verified by a real-time quantitative polymerase chain reaction to infer the degradation pathway of DBP. It was preliminarily predicted that the relative expression of monoester hydrolase of EstB3 is increased in this strain. This study provides a scientific basis for applying S. acidaminiphila BDBP 071 in environmental pollution bioremediation, as well as a rich resource for DBP biodegradation genes. [ABSTRACT FROM AUTHOR]

Atherosclerosis, a leading cause of mortality in developed countries, is characterized by the buildup of oxidized low-density lipoprotein (oxLDL) within the vascular intima, unregulated oxLDL uptake by macrophages, and ensuing formation of arterial plaque. Amphiphilic polymers (AMPs) comprised of a branched hydrophobic domain and a hydrophilic poly(ethylene glycol) (PEG) tail have shown promising anti-atherogenic effects through direct inhibition of oxLDL uptake by macrophages. In this study, five AMPs with controlled variations were evaluated for their micellar and structural stability in the presence of serum and lipase, respectively, to develop underlying structure-atheroprotective activity relations. In parallel, molecular dynamics simulations were performed to explore the AMP conformational preferences within an aqueous environment. Notably, AMPs with ether linkages between the hydrophobic arms and sugar backbones demonstrated enhanced degradation stability and storage stability, and also elicited enhanced anti-atherogenic bioactivity. Additionally, AMPs with increased hydrophobicity elicited increased atheroprotective bioactivity in the presence of serum. These studies provide key insights for designing more serum-stable polymeric micelles as prospective cardiovascular nanotherapies. [ABSTRACT FROM AUTHOR]

Cardiovascular disease initiates with the atherogenic cascade of scavenger receptor- (SR-) mediated oxidized low-density lipoprotein (oxLDL) uptake. Resulting foam cell formation leads to lipid-rich lesions within arteries. We designed amphiphilic macromolecules (AMs) to inhibit these processes by competitively blocking oxLDL uptake via SRs, potentially arresting atherosclerotic development. In this study, we investigated the impact of replacing ester linkages with ether linkages in the AM hydrophobic domain. We hypothesized that ether linkages would impart flexibility for orientation to improve binding to SR binding pockets, enhancing anti-atherogenic activity. A series of tartaric acid-based AMs with varying hydrophobic chain lengths and conjugation chemistries were synthesized, characterized, and evaluated for bioactivity. 3-D conformations of AMs in aqueous conditions may have significant effects on anti-atherogenic potency and were simulated by molecular modeling. Notably, ether-linked AMs exhibited significantly higher levels of inhibition of oxLDL uptake than their corresponding ester analogues, indicating a dominant effect of linkage flexibility on pharmacological activity. The degradation stability was also enhanced for ether-linked AMs. These studies further suggested that alkyl chain length (i.e., relative hydrophobicity), conformation (i.e., orientation), and chemical stability play a critical role in modulating oxLDL uptake, and guide the design of innovative cardiovascular therapies. [ABSTRACT FROM AUTHOR]

Attributed graph anomaly detection aims to identify abnormal nodes that significantly differ from most nodes in terms of their attribute or structure. Recent graph contrastive learning methods, which follow an augmenting-contrasting learning scheme, have shown promising results. However, these methods still have two key limitations. Firstly, the contrastive views generated through random perturbation may not conform to abnormal patterns. Secondly, the inability to effectively discriminate heterophilic edges in anomalous networks can adversely impact the detection performance. To this end, we propose a M ulti-view discriminative E dge heterophi L y c O ntrastive learning N etwork (MELON) for attributed graph anomaly detection. Our approach addresses the aforementioned limitations by integrating human knowledge of different anomaly patterns for data augmentation and designing an edge discriminator to identify edge homophily/heterophily in an unsupervised manner. In addition, a dual-channel encoder is also designed to capture representative representations of the nodes from the discriminated homophilic/heterophilic edges. We then use a decoder to reconstruct the original network from the node representations learned by the dual-channel encoder and rank nodes according to their reconstruction error as the anomaly metric. Extensive experiments on four public benchmark datasets demonstrate that our proposed method outperforms state-of-the-art baselines. • Enhancing data augmentation by merging prior knowledge of diverse abnormal patterns. • Introducing an edge discriminator to distinguish between diverse edge types. • Utilizing several well-designed loss functions to make full use of abnormal signals. [ABSTRACT FROM AUTHOR]

Increased awareness of the abundance and diversity of viruses in soils has led to a growing interest in soil virus ecology. This interest is in part fueled by a need to understand the mechanisms behind the transformation of carbon and nutrient elements within soil ecosystems and what role if any viruses play in these biologically mediated processes. To explore the virus-host distribution and diversity patterns in soil profiles, bacterial community composition and structure, viral and bacterial abundances, and the lysogenic fractions (LF) of bacterial communities were assessed. Enumeration of virus-like particles (VLPs) by epifluorescence microscopy, prophage-induction assays (mitomycin C-based), and bacterial 16S rRNA gene amplicon sequencing were used in this study. The abundances of both extractable VLPs and bacterial cells decreased with soil depth, but VLP abundances decreased more rapidly than bacterial abundances leading to an overall decreasing virus-to-bacteria ratio with depth. In contrast, LF increased with soil depth, indicating lysogeny became a more important reproduction strategy for autochthonous soil bacteriophages in subsurface soil. Significant shifts in bacterial community composition and diversity with soil depth were closely correlated with VLP abundance, virus-to-bacteria ratio, and LF. The results suggest that the viral abundance and replication strategies vary significantly in different soil depths and are linked to microbial host community composition in soil. • Viral and bacterial abundance and virus-to-bacteria ratio decreased with soil depth. • The lysogenic fraction was greater in subsurface than surface soils. • Bacterial community composition varied while diversity decreased with soil depth. • Viral abundance, lysogenic fraction, and burst size were significantly correlated with bacterial community composition. [ABSTRACT FROM AUTHOR]

The aim of this study was to screen for a lactic acid bacterium (LAB) that could improve the quality of whole wheat bread (WWB) and extend its shelf life. The LABs with strong antifungal activity were screened among twenty LABs. Both sourdough properties (rheology, tensility, water mobility and gluten structure) and WWB qualities (texture, volatile flavour and shelf life) were determined and compared. The results showed that the Lactobacillus plantarum LB-1, F-3 and F-50 exhibited stronger antifungal activity among the twenty tested LABs. Moreover, compared to the other LABs, the sourdough fermented by LB-1 demonstrated significantly better viscoelasticity, extensibility, and water holding capacity, as well as a more ordered gluten secondary structure (6.49% more than the control). Meanwhile, Lactobacillus plantarum LB-1 can remarkably improve the texture characteristics, enrich the aroma volatile compounds, and prolong the shelf life of WWB from 3 days to 6 days compared to the control group. Above all, Lactobacillus plantarum LB-1 was recommended for WWB fermentation to improve its quality and to extend the shelf life. • Sourdough and whole wheat bread (WWB) were fermented by Lactobacillus plantarum LB-1. • Sourdough properties and WWB qualities were improved after fermented by LB-1. • LB-1 enabled WWB a better taste and a richer flavor. • The shelf life of WWB fermented by LB-1 was three days longer than the control. [ABSTRACT FROM AUTHOR]

Light-induced charge transfer is one of the key factors to affect photocatalytic activity of heterostructures. Significantly, in metal/semiconductor (M/S) heterostructures the direction of charge transfer is relevant to irradiation wavelength in terms of optical transition of semiconductor and surface plasmon resonance (SPR) of metal. To understand the fundamental photophysical process, herein, we developed a facile double-solvothermal route for fabrication of plasmonic/nonplasmonic-metal/TiO 2 composites with the aid of glycine. Upon UV–visible-light illumination, occurrence of light absorption in plasmonic-metal/TiO 2 composites is originated from optical transition of TiO 2 (UV region) and SPR of plasmonic metal (Au, Ag and Cu, visible region), accounting for reverse charge transfer between them confirmed by transient absorption and photocurrent. Albeit small contribution of SPR effect to photo-generated electrons due to ultrafast electron-phonon scattering, the reverse charge transfer can alleviate photocatalytic performance of these heterostructures to enhance. Hence, well understanding the intrinsic photocatalytic mechanism offers a reliable support to selective construction of sophisticated M/S heterostructure-related polynary photocatalytic systems with high activity. [ABSTRACT FROM AUTHOR]

Beta-cypermethrin (β-CY) is an organic compound that is widely used as a synthetic pesticide in agriculture and family. Excessive accumulation of β-CY inevitably causes environmental pollution, which has led to food safety and human health concerns. Identification of microorganisms from food sources that are capable of β-CY biodegradation may help prevent pollution due to β-CY accumulation. Here, Gordonia alkanivorans GH-1, which was isolated from the traditional Sichuan fermented food, Pixian Doubanjiang, could not only degrade 82.76% of 50 mg/L β-CY at 96 h, but also degraded the intermediate degradation products including dibutyl phthalate (DBP), benzoic acid (BA) and phenol (Ph). This bacterial strain, thus, effectively improved the efficiency of removal of β-CY and its related metabolites, without being limited by toxic intermediates. Whole genome sequencing and transcriptomics analyses have demonstrated that the bacteria affected the transcription of genes related to cell response and material transport under the stress induced by β-CY, and thereby promoted degradation and transformation of β-CY. Moreover, a complete pathway of β-CY degradation is proposed based on the key genes involved in degradation. This study provides important theoretical significance and reference value for eliminating pesticide residues in agricultural products and food to ensure food safety. [Display omitted] • G. alkanivorans GH-1 isolated from fermented food could efficiently degrade β-CY. • Nine intermediate degradation products were identified by GC-MS. • Strain GH-1 did not accumulate toxic products during β-CY degradation. • The genome revealed the potential of strain GH-1 to degrade organic pollutants. • The degradation mechanism was analyzed based on transcriptome sequencing results. [ABSTRACT FROM AUTHOR]

• An ultrahigh-sensitive fiber-optic temperature sensor based on cascaded Sagnac interferometers with a nematic liquid crystal film was proposed and experimentally demonstrated. • The molecules of NLC film changed from isotropic to isotropic just by rotating the two single-mode patch cables without any orientation agent, electric, or magnetic devices. • Experimental results revealed that the temperature sensor based on the cascaded configuration showed an ultrahigh sensitivity of 43.13 nm/°C, which was amplified about 5 times contrast to a single Sagnac interferometer. We demonstrated an ultrasensitive fiber-optic temperature sensor based on cascaded Sagnac interferometers (CSIs). One of the Sagnac interferometers (SIs) consisted of a panda polarization-maintaining fiber (PMF) as the reference arm, while the other one contained two single-mode patch cables in a ferrule matching sleeve as the sensing arm, where a nematic liquid crystal (NLC) film was infiltrated into the micron-scale gap of the sleeve. In the sensing SI, the orientation of NLC film was induced by just rotating the two single-mode patch cables without any orientation agent, electric, or magnetic devices. Vernier effect was acquired by adjusting the thickness of NLC film. Experimental results revealed that the temperature sensitivity of the CSIs was up to 43.13 nm/°C, which was enhanced about 5 times compared to the single NLC SI. The designed optical fiber temperature sensor possessed the merits of compact structure, high stability, ultrahigh sensitivity, low hysteresis effect and high resolution, showing a promising application prospect in some scientific filed requiring accurate temperature measurement, such as biomolecules, medicine and other filed. [ABSTRACT FROM AUTHOR]

• A bubble microcavity in an ultra-thin core optical fiber was fabricated to form a Fabry-Perot interferometer. • The size of the bubble decreased gradually with further arc discharges, which was inverse to the reported literature. • The bubble microcavity in the ultra-thin core optical fiber showed a strain sensitivity of 2.08 pm/με and a gravity sensitivity of 2.908 nm/N in a large measurement range. • The bubble microcavity in the ultra-thin core optial fiber was insensitive to temperature and bending, which was benefit to avoid the cross influences. Recent progress in optical fiber sensors based on Fabry-Perot interferometers (FPIs) has achieved much attention. In this paper, we designed and fabricated an FPI sensor by building a bubble in an ultra-thin core optical fiber. The size of the bubble decreased gradually with further arc discharges, which was inverse to the bubble fabrication in standard single mode fibers and multimode fibers. The bubble microcavity in the ultra-thin core optical fiber demonstrated a strain sensitivity of 2.08 pm/με in the range of 0–5000 με and a gravity sensitivity of 2.908 nm/N in the range of 0–4.89 N with high linear responses. Meanwhile, the bubble microcavity sensor was insensitive to temperature and bending, which was benefit to avoid the cross influences. The FPI sensor based on a bubble microcavity in an ultra-thin core optical fiber possesses the properties of easy to fabricate, small size, robustness, and high sensitivity. [ABSTRACT FROM AUTHOR]

A temperature sensor based on modes coupling effect in a liquid crystal-filled microstructured optical fiber was proposed and studied in this paper. The sensing characteristics were investigated by using a full-vectorial finite-element method (FEM) with perfectly matched layer and scattering boundary condition. For the purpose of temperature sensing, liquid crystal E7 was designed to be infiltrated into one cladding air hole in PCF to form a defect core. As the phase matching condition is satisfied, the core modes couple to several different ordered defect core modes, and finally experience a large increase in the confinement loss spectra. Furthermore, the loss spectra shift toward opposite directions in the two temperature segments (15–29 °C, 29–50 °C) for X-polarized (X-pol) direction, while it experiences a blue shift in the temperature range of 15–50 °C for Y-polarized (Y-pol) direction. Numerical simulation results show that the sensitivity reaches −5.26 nm/°C at 30 °C. The coupling effect between the core fundamental mode and high-order defect core modes utilized in this paper will be beneficial to the high-sensitivity detection. [ABSTRACT FROM AUTHOR]