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Background/Objectives: To investigate the effects of axial elongation on ganglion cell complex (GCC) thickness and retinal capillary density (CD) in the circular region (12 mm diameter) using wide-field swept-source optical coherence tomography angiography. Subjects/Methods: This retrospective and cross-sectional study included 506 eyes. Fovea-centred 15 × 12 mm² scans were acquired to measure the subregional GCC thickness and CD in the whole retina, superficial capillary plexus (SCP) and deep capillary plexus (DCP) among three groups: normal controls, high myopia (HM) eyes with an axial length (AL) 28 mm. The magnitude of GCC thickness and retinal CD changes with axial elongation was estimated using multivariable linear regression models. Results: The GCC thickness and retinal CD in HM eyes with an AL >28 mm were lesser than those in the other two groups in most regions (P

Background: Public complaints concerning odor emissions from intensive livestock and poultry farms continue to grow, as nauseous odorous compounds have adverse impacts on the environment and human health. Itaconic acid is a metabolite from the citric acid cycle of the host and shows volatile odor-reducing effects during animal production operations. However, the specific role of itaconic acid in decreasing intestinal odorous compound production remains unclear. A total of 360 one-day-old chicks were randomly divided into 6 treatments: control group (basal diet) and itaconic acid groups (basal diet + 2, 4, 6, 8 and 10 g/kg itaconic acid, respectively). The feeding experiment lasted for 42 d. Results: Dietary itaconic acid supplementation linearly and quadratically decreased (P < 0.05) the cecal concentrations of indole and skatole but did not affect (P> 0.05) those of lactic, acetic, propionic and butyric acids. The cecal microbial shift was significant in response to 6 g/kg itaconic acid supplementation, in that the abundances of Firmicutes, Ruminococcus and Clostridiumwas increased (P < 0.05), while that of Bacteroidetes, Escherichia-Shigella and Bacteroides were decreased (P < 0.05), indicative of increased microbial richness and diversity. Furthermore, a total of 35 significantly (P < 0.05) modified metabolites were obtained by metabolomic analysis. Itaconic acid decreased (P < 0.05) the levels of nicotinic acid, nicotinamide, glucose-6-phosphate, fumatic acid and malic acid and increased (P< 0.05) 5-methoxytroptomine, dodecanoic acid and stearic acid, which are connected with the glycolytic pathway, citrate acid cycle and tryptophan metabolism. Correlation analysis indicated significant correlations between the altered cecal microbiota and metabolites; Firmicutes, Ruminococcus and Clostridiumwere shown to be negatively correlated with indole and skatole production, while Bacteroidetes, Escherichia-Shigellaand Bacteroides were positively correlated with indole and skatole production. Conclusions: Itaconic acid decreased cecal indole and skatole levels and altered the microbiome and metabolome in favor of odorous compound reduction. These findings provide new insight into the role of itaconic acid and expand its application potential in broilers.

Carotid endarterectomy (CEA) has been the standard therapy for carotid artery stenosis (CAS). Modified eversion carotid endarterectomy (mECEA) was recently introduced to treat CAS. However, the short-term safety and long-term efficacy of mECEA are still controversial among studies. This systematic review aims to summarize the current literatures about safety and efficacy of mECEA in treating CAS.A systematic review of mECEA was conducted in the main bibliographic databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Clinical studies on the safety and efficacy of mECEA in treating CAS with clinical results of transient ischemic attack (TIA), stroke, death, and restenosis were included.The initial search and screening found 15 references from the main databases, and 7 studies were finally included after full-text article assessment, which consisted of 3 single-arm studies and 4 comparative studies. The risks of postoperative complications including TIA, stroke, myocardial infarction (MI), and death ranged from 1.1% to 2%, 0% to 2.5%, 0% to 4.4%, and 0% to 2.32%, respectively. The mECEA was significantly related to lower risk of carotid artery occlusion, incision numbness, and shorter lengths of stay in hospital and average scar when separately compared with conventional CEA (cCEA), CEA with patch closure (pCEA), and eversion CEA (eCEA).The mECEA is a promising surgical option for CAS with acceptable clinical outcomes. In order to prove its safety and efficacy, future practices need to be conducted by more medical workers in more large-scale trials.

Graphene oxide (GO) is a versatile material with inherent unique properties that can be used in a wide range of applications. GO is produced from graphitic materials including graphite, and its properties can depend on the nature of stacking in the graphene structures. In this study, GO was prepared from pitch-based graphite fibers via the modified Hummer's method and subsequently incorporated into an epoxy matrix to obtain grapheneloaded nanocomposites (EP/GO). Presented experimental results revealed that the addition of 0.6 wt% GO yielded an similar to 110% increase in the fracture toughness. The corresponding fracture energies as well as the flexural strengths and flexural modulus exhibited similar trends to the fracture toughness. The thermophysical properties of the EP/GO, to further demonstrate the reinforcing effectiveness of GO, were also observed. Collectively, these results indicate that GO investigated in the study can be a viable reinforcement candidate to develop next-generation nanocomposites with multifunctional properties. Technology Innovation Program (Industrial Strategic Technology Development Program - Development of Techno-logy on materials and components) - Ministry of Trade, Industry & Energy (MOTIE, Korea) [20010106]; Technological Innovation R&D Program - Small and Medium Business Administration (SMBA, Korea) [S2849653] Published version Funding information: This work was supported by the Technology Innovation Program (or Industrial Strategic Technology Development Program - Development of Techno-logy on materials and components) (20010106, Adhesives with low water permeability and low outgassing) funded by the Ministry of Trade, Industry & Energy (MOTIE, Korea) and supported by the Technological Innovation R&D Program (S2849653) funded by the Small and Medium Business Administration (SMBA, Korea) .

Heterocyclic Mannich bases

IntroductionConventional lipid-lowering agents, including statins, ezetimibe, fibrates, bile acid sequestrants, nicotinic acid, bempedoic acid and Omega-3, are essential to the management of dyslipidaemia. However, these agents have been shown to increase the level of plasma proprotein convertase subtilisin/kexin 9 (PCSK9), a serine protease associated with increased cardiovascular risk. This review aims to investigate the impact of commonly available conventional lipid-lowering agents on circulating PCSK9 levels and lipid profiles.Methods and analysisThis protocol is conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidelines. A systematic search will be conducted in the following databases: MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, Web of Science, SCOPUS and ScienceDirect. Additional information will be retrieved from clinical trial registries or from reference list searches. Published and peer-reviewed randomised controlled trials with adults receiving statin, ezetimibe, fibrate, bile acid sequestrant, nicotinic acid, bempedoic acid or Omega-3 monotherapy or in combination for at least 2 weeks, with availability of plasma PCSK9 at the beginning and end of treatment or the net changes in values, will be included. Study selection, data extraction and assessment of the risk of bias will be independently conducted by two investigators. Continuous data will be presented as a standardised mean difference with 95% confidence interval (CI) and dichotomous data as risk ratios with 95% CI. Subgroup analysis and sensitivity analysis will be performed when sufficient studies are included. Publication bias will be assessed with a funnel plot and Egger’s test.Ethics and disseminationEthics approval is not required as this review will only include data from published sources. The results will be published in a peer-reviewed journal.Patient and public involvementNo patient or members of the general public are involved.PROSPERO registration numberCRD42022297942.

Interfacial interaction is one of the most crucial and dominant factors affecting the performance and behavior of a material. The surfaces of layered expanded graphite (EG) were activated by covalently grafted mercapto groups (-SH), which can readily react with the macromolecular chains of rubber, thus forming a strong interfacial adhesion between the filler and the rubber matrix. Shear-induced mercapto-group-activated graphite nanoplatelets (S@GNPs) were fabricated in situ by compound mixing in a two-roll mill. A correlation between the interfacial interaction and the thermal conductivity, as well as the thermo-physical properties, was comprehensively investigated. The results showed that rubber/S@GNPs composites exhibited better mechanical performance, enhanced thermo-physical properties, and superior thermal conductivity, all of which could be attributed to the stronger interfacial interaction resulting from chemical bonding between the S@GNPs and the molecular chains of the rubber, relative to XSBR/GNP composites connected by weaker π-π stacking.

Diamond is a metastable allotrope of carbon. Monocrystalline diamond with particle size less than 100 nm (designated as nanodiamond) has been widely studied during the past decades. Nanodiamonds have recently attracted attention owing to their exceptional mechanical and optical properties, tunable surface structure, and high specific surface area. The specific core-shell structure and abundant functional groups on its surface endow it with a variety of functional applications. Their excellent physical properties enable their application as ideal fillers in reinforcing polymer composites, resulting in superior mechanical properties, thermal stability, thermal conductivity and tribological properties. In addition to polymer composites, nanodiamonds and its composites are also widely used in sensors, optical computing, and quantum computing. As nanoscale materials, nanodiamonds and its composites are also used in electrical energy storage, wastewater treatment and bioapplications. Due to its superior biocompatibility and low cytotoxicity, nanodiamonds and its composites are now becoming crucial in biological applications. In this study, the properties of nanodiamonds and their application in polymer composites, electronics, energy, environmental areas and biological areas were analyzed.

Amine-terminated macromolecular chain (ATBN) were covalently grafted on expanded graphite (EG) surface using 4,4′-methylene diphenyl diisocyanate as coupling agent. The functionalization result of the amine-terminated EG (AEG) was demonstrated by various analysis techniques. The AEG was incorporated into the epoxy (EP) matrix to form EP/AEG nanocomposites by interlayer polymerization in the EG interval layers. The grafted ATBN chains on the AEG surfaces can not only enhance the interfacial adhesion of the filler and EP matrix, but can also act as hardener to react with the EP chains covalently to further toughen the fabricated EP nanocomposites. The thermal stability, thermal conductivity, thermos-mechanical, and rheological properties of the EP/AEG nanocomposites were comprehensively studied. The results showed that the novel-designed AEG can significantly enhance the thermal conductivity of the EP composites. Moreover, the as-designed composites show superior thermal stability and thermo-physical properties, making them potentially useful as thermal management materials in electronic devices.

This research focused on evaluating the thermal and physical properties of a composite reinforced with nanodiamonds and epitaxial boron nitride in an epoxy matrix. Nanodiamond-attached exfoliated hexagonal boron nitride nanoplates were fabricated using 4,4′-methylene diphenyl diisocyanate as the coupling agent. The morphology and structure of boron nitride (BN), exfoliated hexagonal BN nanoplates (EBN), and nanodiamond-attached EBN nanoplates (NDEBN) were determined. Epoxy composites were fabricated by in-situ polymerization and reinforced with various concentrations of either EBN or NDEBN nanoplates. These composites exhibited high thermal stability and high thermal conductivity, attributed to the exceptional thermal stability and thermal conductivity inherent in nanodiamond materials. In addition, inserting nanodiamond particles between BN layers prevented the BN nanosheet from forming agglomerates. We also found that nanodiamond particles improved dynamic mechanical properties by acting as a crack pinning role, which could restrict the molecular mobility of the epoxy.

Novel hybrid fillers composed of nanodiamond (ND) nanocluster-decorated graphene oxide (GO) were fabricated and incorporated in an epoxy matrix using a facile thermoregulatory liquid-liquid extraction method. X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy analyses confirmed a chemical bonding between the (3-aminopropyl)triethoxysilane-functionalized ND and (3-glycidyloxypropyl)trimethoxysilane-functionalized GO. The morphology of the hybrid filler (GN) was characterized by field-emission transmission electron microscopy. ND nanoclusters with an average diameter of 50–100 nm were uniformly grown on the GO surface. The hybrid filler provided significant enhancement of mechanical properties, such as flexural strength, flexural modulus, and fracture toughness. In particular, the epoxy composite containing 0.1 wt% of GN hybrid exhibited a stronger mechanical behavior compared to that containing 0.2 wt% of GO. As the GN loading increased, the thermal stability, the integral procedural decomposition temperature, and the activation energy increased as well. The toughening mechanism was illustrated by a microcrack theory based on the microscopic analysis of the fracture surfaces. The presence of ND nanoclusters not only hindered the aggregation of the GO sheets, but also played a crack pinning role in the polymer-matrix composites, which could significantly enhance its fracture toughness.

In the past few decades, organic thermoelectric materials/devices, which can exhibit remarkable potential in green energy conversion, have drawn great attention and interest due to their easy processing, light weight, intrinsically low thermal conductivity, and mechanical flexibility. Compared to traditional batteries, thermoelectric materials have high prospects as alternative power generators for harvesting green energy. Although crystalline inorganic semiconductors have dominated the fields of thermoelectric materials up to now, their practical applications are limited by their intrinsic fragility and high toxicity. The integration of organic polymers with inorganic nanoparticles has been widely employed to tailor the thermoelectric performance of polymers, which not only can combine the advantages of both components but also display interesting transport phenomena between organic polymers and inorganic nanoparticles. In this review, parameters affecting the thermoelectric properties of materials were briefly introduced. Some recently developed n-type and p-type thermoelectric films and related devices were illustrated along with their thermoelectric performance, methods of preparation, and future applications. This review will help beginners to quickly understand and master basic knowledge of thermoelectric materials, thus inspiring them to design and develop more efficient thermoelectric devices.

Novel hybrid nanofillers composed of nanodiamond-attached graphite nanoplatelets (ND@GNPs) were designed and employed to toughen the epoxy (EP) matrix for fabricating superior thermal conductive and physically robust thermoset nanocomposites for electronics and auto industries. The hybrid nanofiller was covalently bonded by 4,4′-diphenylmethane diisocyanate and it provided distinct enhancement in thermal conductivity and dynamic storage modulus of the EP/ND@GNPs nanocomposites attributing to the unique nanostructure of ND@GNPs that can form strong interfacial interaction with EP matrix, thus restrict the EP molecular motions. The EP/ND@GNPs20 presented a thermal conductivity of 2.48 W · m−1 · K−1 and dynamic storage modulus of 5.6 GPa. The presence of ND particles not only can enhance heat transfer efficiency but also improve the interfacial interaction between ND and EP matrix, which can directly affect physical properties of the EP composites.

Thermoelectric devices have recently attracted considerable interest owing to their unique ability of converting heat to electrical energy in an environmentally efficient manner. These devices are promising as alternative power generators for harvesting electrical energy compared to conventional batteries. Inorganic crystalline semiconductors have dominated the thermoelectric material fields; however, their application has been restricted by their intrinsic high toxicity, fragility, and high cost. In contrast, organic thermoelectric materials with low cost, low thermal conductivity, easy processing, and good flexibility are more suitable for fabricating thermoelectric devices. In this review, we briefly introduce the parameters affecting the thermoelectric performance and summarize the most recently developed carbon-material-based organic thermoelectric composites along with their preparation technologies, thermoelectric performance, and future applications. In addition, the p- and n-type carbon nanotube conversion and existing challenges are discussed. This review can help researchers in elucidating the recent studies on carbon-based organic thermoelectric materials, thus inspiring them to develop more efficient thermoelectric devices.

Polymer-based thermoelectric materials have attracted considerable interest for green energy conversion over the past decades. In this study, polymer/inorganic thermoelectric generators were prepared by integrating film-forming polyvinylidene fluoride (PVDF) and expanded graphites (EGs) to tailor the thermoelectric performance of the resulting PVDF/EG composites by adjusting the expansion volume of EGs with different thermal treatments. The charge carrier rate and phonon scattering are responsible for the divergent performance of the prepared polymer/EG composites. The prepared composites exhibited superior thermoelectric properties, where the PVDF/EG composite containing 20% EG expanded at 600 °C showed an electrical conductivity of 883 S/cm, a Seebeck coefficient of 8.77 μV/K, and a high power factor of 6.79 μW m−1K−2. This composite outperforms many other graphene- or graphite-based composites reported in the literature. This study provides a facile avenue to prepare an inexpensive, lightweight, nontoxic, and highly efficient thermoelectric generator for green energy conversion and energy harvesting.