Fiber Diameter Research Articles

Measuring Fiber Positioning Accuracy and Throughput with Fiber Dithering for the Dark Energy Spectroscopic Instrument

Highly multiplexed, fiber-fed spectroscopy is enabling surveys of millions of stars and galaxies. The performance of these surveys depends on accurately positioning fibers in the focal plane to capture target light. We describe a technique to measure the positioning accuracy of fibers by dithering fibers slightly around their ideal locations. This approach also enables measurement of the total system throughput and point-spread function delivered to the focal plane. We then apply this technique to observations from the Dark Energy Survey Instrument (DESI), and demonstrate that DESI positions fibers to within 0.″08 of their targets (5% of a fiber diameter) and achieves a system throughput within about 7% of expectations.

Bone marrow derived mesenchymal stem cells enriched PCL-gelatin nanofiber scaffold for improved wound healing

Electrospun nanofibers exhibit a significant potential in the synthesis of nanostructured materials, thereby offering a promising avenue for enhancing the efficacy of wound care. The present study aimed to investigate the wound-healing potential of two biomacromolecules, PCL-Gelatin nanofiber adhered with bone marrow-derived mesenchymal stem cells (BMSCs). Characterisation of the nanofiber revealed a mean fiber diameter ranging from 200 to 300 nm, with distinctive elemental peaks corresponding to polycaprolactone (PCL) and gelatin. Additionally, BMSCs derived from bone marrow were integrated into nanofibers, and their wound-regenerative potential was systematically evaluated through both in-vitro and in-vivo methodologies. In-vitro assessments substantiated that BMSC-incorporated nanofibers enhanced cell viability and crucial cellular processes such as adhesion, and proliferation. Subsequently, in-vivo studies were performed to demonstrate the wound-healing efficacy of nanofibers. It was observed that the rate of wound healing of BMSCs incorporated nanofibers surpassed both, nanofiber and BMSCs alone. Furthermore, histomorphological analysis revealed accelerated re-epithelization and improved wound contraction in BMSCs incorporated nanofiber group. The fabricated nanofiber incorporated with BMSCs exhibited superior wound regeneration in animal model and may be utilised as a wound healing patch.

The Influence of Physical Characteristics of Wet Wipe Fabrics on the Microbial Biomass Accumulation

The physicochemical properties of nonwoven wet wipe fabrics have a strong influence on the ability of microorganisms to attach and multiply, until a biofilm is formed. Cellulose-based fabrics, being biodegradable, represent a major contamination risk. In addition, having a hydrophilic nature, they provide a good platform for microorganisms attachment. To optimize biodegradable wet wipes antimicrobial quality, it is crucial to assess the impact of physicochemical properties, e.g., density, pore size, fiber diameter, contact angle and surface charge. Here, we investigated the physical characteristics of commonly used nonwoven fabrics from both synthetic (Polyethylene terephthalate, PET) and natural components (wood pulp and viscose), to evaluate their effect on microbial contamination. We found that the hydrophobicity of the fabric had varying influence on attachment, depending on the microbial strain. However, the geometry, as well as the fabric pore size greatly affected attachment regardless of the microbial strain, in which a larger pore size resulted in lower accumulation of microbial biomass. Our study gives insight into the characteristics of wet wipes that can affect the preservation efficacy and microbial contamination risk, in one of the biggest segments in the personal care industry.

Effects of dietary arginine supplementation on muscle structure, meat characteristics and lipid oxidation products in lambs and its potential mechanisms of action

This study aimed to assess the effect of dietary arginine supplementation on muscle structure and meat characteristics of lambs also considering lipid oxidation products and to contribute to reveal its mechanisms of action using tandem mass tagging (TMT) proteomics. Eighteen lambs were allocated to two dietary treatment groups: control diet or control diet with the addition of 1% L-arginine. The results revealed that dietary arginine supplementation increased muscle fibre diameter and cross-sectional area (P < 0.05), which was attributable to protein deposition, as evidenced by increased RNA content, RNA/DNA ratio, inhibition of apoptotic enzyme activity, and alterations in the IGF-1/Akt signaling pathway (P < 0.05). In addition, dietary arginine elevated pH24h, a* values, and IMF content, decreased shear force value and backfat thickness (P < 0.05), as well as decreased the formation of lipid oxidation products involved in meat flavor including hexanal, heptanal, octanal, nonanal and 1-octen-3-ol by increasing the antioxidant capacity of the muscle (P < 0.05). The proteomics results suggested that seven enrichment pathways may be potential mechanisms by which arginine affected the muscle structure and meat characteristics of lambs. In summary, arginine supplementation in lamb diets provides a safe and effective way to improve meat quality, and antioxidant capacity of muscle of lamb.

HIV infection and ART use are associated with altered plasma clot characteristics in Black South Africans.

Human immunodeficiency virus (HIV) and antiretroviral treatment (ART) are both associated with hypercoagulability. Altered clot properties could be a potential mechanism thereof. We aimed to investigate the association of HIV and ART, with fibrinogen and plasma clot properties in a group of Black South Africans. At baseline, 151 newly diagnosed people living with HIV (PLWH) and 176 controls were recruited. Some PLWH subsequently commenced with ARTs (n = 70) while others remained ART-naïve (n = 81). Fibrinogen and clot properties (turbidity assay) were investigated from baseline to 5-year follow-up. A sub-group of 21 women (n = 10 ART-treated; n = 11 ART-naïve) with HIV was systematically selected and matched with 12 controls, and additional clot properties (rheometry, permeability and fibre diameter) were investigated. Fibrinogen was lower in the HIV groups compared to the controls, while % γ' fibrinogen was higher. PLWH had shorter lag times and lower maximum absorbance than the controls (p<0.05). Their CLTs on the other hand were longer. Most variables increased over time in all groups, but differences in the degree of change over time was observed for lag time (p = 0.024) and permeability (p = 0.03). Participants who commenced with ART had a tendency of delayed clot formation (p = 0.08) and increased clot permeability (p = 0.005). PLWH had lower total fibrinogen concentration and formed less dense clots. They also formed clots that were more difficult to lyse, which likely not resulted from altered clot properties. ART use (NNRTI's) had a moderately protective effect, delaying clot formation, and increasing clot permeability.

A visual ratio PVA/curcumin/indigo nanofibre membrane based on natural pigments for detecting mutton freshness

SummaryIn the storage process, meat is susceptible to external factors that produce corruption and deterioration, affecting consumers' health. Therefore, preparing an indicator membrane that can detect freshness in real time, non‐destructively, and visually is significant. Herein, an indicator membrane was prepared by electrostatic spinning technology using polyvinyl alcohol (PVA) as the substrate and curcumin (CUR) and indigo (IND) as the mixed indicator for freshness detection. When curcumin and indigo were mixed at 3:1 (w/w), CUR was transformed from ketone type to enol type with the gradual increase of pH, and IND underwent electron leaps, which resulted in green, brown, and reddish‐brown colour changes in the solution, and the colour development effect was effectively improved. The characterisation results showed that the average fibre diameter of the PVA/0.8 indicator membrane was 252 nm, the hybrid indicator was successfully loaded in the nanofibres, and the water contact angle was 103.6°, which was hydrophobic. In addition, the indicator membrane was sensitive to trimethylamine (limit of detection 17.38 ppm) and triethylamine (limit of detection 27.77 ppm) but insensitive to saline, ethanol, ethyl acetate, and other contaminants with detection specificity. Finally, the colour of the indicating membrane changes from green to brown during the storage of mutton in the mutton was rotten, indicating that the naked eye can judge the freshness of the mutton. Therefore, the PVA/CUR/IND indicator membrane has excellent potential for application in real‐time and non‐destructive detection of mutton freshness.

Electrospun Composites of Chitosan with Cerium Oxide Nanoparticles for Wound Healing Applications: Characterization and Biocompatibility Evaluation In Vitro and In Vivo.

Cerium oxide nanoparticles (CeONPs), as part of tissue regeneration matrices, can protect cells from reactive oxygen species and oxidative stress. In addition, they can influence the properties of the scaffold, including its electrospinnability and mechanical strength. In this work, we prepared electrospun fiber mats from a chitosan and polyethylene oxide blend (CS-PEO) with the addition of ceria nanoparticles (CS-PEO-CeONP). The addition of CeONPs resulted in a smaller fiber diameter and higher swelling compared to CS-PEO fiber mats. CeONP-modified fiber mats also had a higher Young's modulus due to the reinforcing effect of the nanoparticles. Both mats had comparable adhesion and cytocompatibility to mesenchymal stem cells, which had a more rounded morphology on CS-PEO-CeONP compared to elongated cells on the CS-PEO mats. Biocompatibility in an in vivo rat model showed no acute toxicity, no septic or allergic inflammation, and no rough scar tissue formation. The degradation of both mats passed the stage of matrix swelling. CS-PEO-CeONP showed significantly slower biodegradation, with most of the matrix remaining in the tissue after 90 days. The reactive inflammation was aseptic in nature with the involvement of multinucleated foreign-body type giant cells and was significantly reduced by day 90. CeONPs induced the formation of the implant's connective tissue capsule. Thus, the introduction of CeONPs influenced the physicochemical properties and biological activity of CS-PEO nanofiber mats.

Aligned polycaprolactone/polyaniline electrospun nanofibers for directing neural stem cell differentiation and neuron arrangement

The use of engineered biomimetic substrates combined with neural stem cells (NSCs) constitutes a promising approach to develop reliable in vitro models of the nervous tissue. The fabrication of scaffolds with suitable compositional, topographical, and electrical properties is crucial for directing neural cell adhesion, differentiation, and arrangement. Herein, we propose the development of electroconductive polycaprolactone/polyaniline (PCL/PANI) electrospun mats as functional substrates for NSC culture. A rotating drum collector was employed to obtain fibers with aligned geometry. According to the results, the increase in alignment contributed to the reduction of fiber diameter and the increase of scaffold mechanical properties in terms of elastic modulus and tensile strength. In vitro experiments demonstrated the ability of PCL/PANI membranes to support NSC attachment and growth, as well as significantly foster neuronal differentiation. Furthermore, the presence of an aligned pattern was shown to effectively influence the arrangement of NSC-derived neurons, confirming the potential of this substrate for the design of a physiologically relevant culture platform for in vitro investigation of the nervous tissue.

Electrospun lavender essential oil-loaded polylactic acid nanofibrous mats for antioxidant applications

In this study, the lavender essential oil-incorporated polylactic acid (PLA) nanofibers were fabricated by the electrospinning technique with the presence of kolliphor as a nonionic surfactant. The FTIR spectra supported the chemical composition of the fibers. The FTIR spectra demonstrated that there is no chemical reaction present between PLA and lavender essential oil. The SEM images of all nanofibers showed bead-free morphology. ImageJ results showed that the average diameter of lavender oil-loaded fibers ranged between 121.6 ± 32 and 228.2 ± 53 nm. All lavender essential oil-incorporated nanofibers were hydrophobic with satisfactory thermal properties. Furthermore, the lavender essential oil-incorporated PLA nanofibrous mats exhibited good antioxidant activity. The results showed that as the concentration of the essential oil in resulting nanofibers increased, the antioxidant activity also increased. According to the results of this study, lavender essential oil-loaded PLA fibers can be considered for a wide range of potential applications such as active packaging, food coating, facial masks, and wound dressing.

Preparation of β-cyclodextrin/PVDF composite films for efficient adsorption of Cu2+

Water pollution issues are becoming more and more serious, particularly those caused by heavy metal ions. In this paper, β-cyclodextrin (β-CD) and polyvinylidene fluoride (PVDF) were chosen to prepare composite films by electrospinning technology. The microstructure, crystalline phases, mechanical properties, porosity, and adsorption performance of β-CD/PVDF composite films were analyzed. The results show that the β-CD/PVDF composite fibers were smooth and randomly deposited to form an interconnected three-dimensional network structure. The diameter of the β-CD/PVDF composite fibers ranged from 0.22 to 0.33 μm, and the fiber diameter distribution was uniform. The maximum porosity was 79.56% when the content of β-CD was 2%. After adding the β-CD, the tensile strength increased to 13.33 MPa and the elongation at break increased to 14.20% as well. With the β-CD content increasing, the adsorption capacity of the β-CD/PVDF composite films for Cu2+ increased to 182.65 mg g−1. In addition, the second-order kinetic model was suitable to describe the adsorption process, and the chemical adsorption was the predominant mechanism of the adsorption process due to the presence of β-CD. The results suggest that the β-CD/PVDF composite films may be a potential adsorbent for Cu2+ adsorption.

Two-Dimensional Piezoelectric Nanofibrous Webs by Self-Polarized Assembly for High-Performance PM0.3 Filtration.

Particulate matter (PM) pollution has posed a serious threat to public health, especially the global spread of infectious diseases. Most existing air filtration materials are still subjected to a compromise between removal efficiency and air permeability on account of their stacking bulk structures. Here, we proposed a self-polarized assembly technique to create two-dimensional piezoelectric nanofibrous webs (PNWs) directly from polymer solutions. The strategy involves droplets deforming into ultrathin liquid films by inertial flow, liquid films evolving into web-like architectures by instantaneous phase inversion, and enhanced dipole alignment by cluster electrostatics. The assembled continuous webs exhibit integrated structural superiorities of nanoscale diameters (∼20 nm) of the internal fibers and through pores (∼100 nm). Combined with the wind-driven electrostatic property derived from the enhanced piezoelectricity, the PNW filter shows high efficiency (99.48%) and low air resistance (34 Pa) against PM0.3 as well as high transparency (84%), superlight weight (0.7 g m-2), and long-term stable service life. This creation of such versatile nanomaterials may offer insight into the design and upgrading of high-performance filters.

Development of Bioactive Hybrid Poly(lactic acid)/Poly(methyl methacrylate) (PLA/PMMA) Electrospun Fibers Functionalized with Bioglass Nanoparticles for Bone Tissue Engineering Applications.

Hybrid scaffolds that are based on PLA and PLA/PMMA with 75/25, 50/50, and 25/75 weight ratios and functionalized with 10 wt.% of bioglass nanoparticles (n-BG) were developed using an electrospinning technique with a chloroform/dimethylformamide mixture in a 9:1 ratio for bone tissue engineering applications. Neat PLA and PLA/PMMA hybrid scaffolds were developed successfully through a (CF/DMF) solvent system, obtaining a random fiber deposition that generated a porous structure with pore interconnectivity. However, with the solvent system used, it was not possible to generate fibers in the case of the neat PMMA sample. With the increase in the amount of PMMA in PLA/PMMA ratios, the fiber diameter of hybrid scaffolds decreases, and the defects (beads) in the fiber structure increase; these beads are associated with a nanoparticle agglomeration, that could be related to a low interaction between n-BG and the polymer matrix. The Young's modulus of PLA/PMMA/n-BG decreases by 34 and 80%, indicating more flexible behavior compared to neat PLA. The PLA/PMMA/n-BG scaffolds showed a bioactive property related to the presence of hydroxyapatite crystals in the fiber surface after 28 days of immersion in a Simulated Body Fluids solution (SBF). In addition, the hydrolytic degradation process of PLA/PMMA/n-BG, analyzed after 35 days of immersion in a phosphate-buffered saline solution (PBS), was less than that of the pure PLA. The in vitro analysis using an HBOF-1.19 cell line indicated that the PLA/PMMA/n-BG scaffold showed good cell viability and was able to promote cell proliferation after 7 days. On the other hand, the in vivo biocompatibility evaluated via a subdermal model in BALC male mice corroborated the good behavior of the scaffolds in avoiding the generation of a cytotoxic effect and being able to enhance the healing process, suggesting that the materials are suitable for potential applications in tissue engineering.

Effects of Different Fiber Sizes in PLA/Carbon Fiber Composites on Mechanical Properties

This study assessed the morphology and chemical composition of coir coconut husk carbon fiber, as well as the impact of fiber diameters on the physical and mechanical properties of polylactic acid composites. Researchers are studying polylactide acid, a biodegradable material. This eco-friendly material’s excellent features, generated from sustainable and renewable sources, have drawn many people. Malaysia’s high coconut fiber output made coir husk a popular commodity. Coconut fibers are lignin, cellulose, and hemicellulose. Alkaline treatment eliminates hemicellulose, oil, wax, and other contaminants from coir fibers and removes lignin. Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy were used to examine the treated coconut fibers’ chemical modification analysis and morphology. Coconut coir husk was carbonized to produce carbon fiber using a furnace operated at 300°C for 2 hours. Fiber and polylactic acid were mixed in different fiber sizes (0, 53 μm, 75 μm, and 212 μm) via extrusion and injection processing techniques. The results showed that the alkali treatment reduced the hydroxyl (-OH) group and separated the area from the carbonyl (C=O) group of coconut coir husk, which changed the filler’s hydrophilicity. The fiber size of 212 μm was discovered to have the highest tensile and flexural strength values. According to testing, the modified material structure had a better surface fill-matrix bond. Thus, generalized fiber sizing and characterization methods were developed. Regardless of the matrix, this method can characterize natural fiber strength and interfacial shear strength of varied diameters and solid contents.

Preparation and characterization of poly (lactic acid)-chitosan blend fibrous electrospun membrane loaded with bioactive glass nanoparticles for guided bone/tissue regeneration

In this study, bioactive fibrous membranes composed of poly (lactic) acid (PLA), chitosan (CHS), and strontium-doped bioactive glass nanoparticles (BG) were produced via electrospinning technique using a triple solvent system and characterized via thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), static contact angle (CA), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX).All fiber samples exhibited consistent one-step thermal degradation profiles, regardless of BG content, and the intended BG contents in the membranes ware confirmed. The addition of 3% w/w CHS to form PLA-CHS blend lowered the glass transition temperature (Tg) by 1.62 °C. FTIR analysis validated the presence of CHS in the PLA-CHS blend fibers through the appearance of a low-intensity broad peak around 1658–1566 cm⁻1, indicating primary amide functional groups. Incorporating 3% w/w CHS reduced water contact angle by 7% and decreased fiber diameter by 57%. Wettability improved with increasing BG content, as confirmed by SEM images showing well-dispersed BG nanoparticles within the fibers.After 35 days of immersion in simulated body fluid (SBF), a substantial layer of hydroxyapatite (HA) with a Ca/P ratio resembling that of natural human bones coated the BG particles and fibers. The membranes demonstrated excellent cell adhesion capabilities, especially in the PLA_3%CHS and PLA_3% CHS_5% BG configurations, with minimal cellular toxicity compared to a well-known cell-killing agent, highlighting their biocompatibility.Incorporating chitosan and strontium-doped bioactive glass nanoparticles into PLA blends positively influenced cell viability and proliferation, emphasizing the enhanced cellular response resulting from surface modifications. These properties make these fibrous membranes promising for guided bone and tissue regeneration applications.

Investigate the Processability of Biobased Thermoplastics Used in Nonwoven Fabrics.

The Covid-19 pandemic increased enormously the manufacturing and usage of face masks and other personal protective equipment (PPE), resulting in accumulation of plastic waste and, thus, causing universal environmental concerns. In addressing the issue of waste reduction and finding alternatives for fossil-based products, investigation of different biobased and biodegradable polymers plays a crucial role. This study examines the processability characteristics of three commonly used biobased polymers available in the market: biobased poly(lactic acid) (PLA), partly biobased and biodegradable poly(butylene succinate) (PBS), and biobased high-density poly(ethylene) (BioHDPE). The investigation combines substantial polymer analysis with subsequent processability trials in two different spunmelt processes, namely, meltblow (MB) and the Nanoval technology, aiming to reveal the differences and difficulties in the processing behavior and pointing out advantages and/or disadvantages of the respective polymer/technology combination. In general, the observed processability behavior and outcomes indicate that within the used processes PLA exhibits superior processability compared to PBS and BioHDPE. Both the meltblow and Nanoval processing of PLA demonstrated a consistent production of fibers and efficient uptake without any compromise on the throughput. In contrast, the processing of PBS using Nanoval required the utilization of significantly elevated temperatures, as indicated by a rheological study. Furthermore, the rheological evaluation revealed that the viscosity of BioHDPE was excessively elevated, rendering it unsuitable for effective processing by the Nanoval method. The microfibers in the PLA-based meltblown fabric had a higher surface area, explaining why the PLA fibers were able to function as a barrier and, thus, contribute to the mitigation of air permeability adjustable between 500 and 1000 l·s-1·m-2 and thus competitive or even superior to PP nonwovens of the same fiber diameter and base weight (1480 l·s-1·m-2). Overall, these results showed that PLA can be an alternative raw material for fossil-based nonwovens of PPE applying, especially, the meltblown technique.

Rice straw-based cellulose nanofiber reinforcing polyvinyl alcohol antibacterial film through electrospinning

TEMPO-cellulose nanofibers (T-CNF) were prepared from rice straw through 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidation method. Subsequently, T-CNF reinforced polyvinyl alcohol fiber films (T-CNF/PVA) were fabricated by electrospinning. SEM images revealed that the introduction of T-CNF into PVA resulted in a slight decrease in fiber diameter within the T-CNF/PVA films. The tensile strength and elastic modulus of the T-CNF/PVA-2 fiber film were 44.59 MPa and 20.75 MPa, respectively, with T-CNF content of 1.64 wt%. The tensile strength of T-CNF/PVA-2 being approximately 9 times greater than that of pure PVA fiber film. Molecular dynamics (MD) simulation showed that the intermolecular forces between T-CNF and PVA were stronger than those within pure PVA. Additionally, the T-CNF/PVA-2 fiber film exhibited excellent antibacterial properties, achieving an inhibition rate of 99.99 % against S. aureus.

Functional Technical Textile-Based Polymer Nanocomposites with Adsorbent Properties of Toxins and Dyes also Have Antibacterial Behavior.

This is the first study of non-woven fabrics elaborated by melt-blowing from polymer nanocomposites made of Nylon 6 and nanoclay (Cloisite 20A) modified with an amine (1,4 diaminobutane dihydrochloride). Morphological and physical characteristics, adsorption capacity, and antibacterial properties are presented. From the X-ray diffraction (XRD) results, it was possible to observe a displacement of the signals to other 2θ angles, due to an α to ϒ phase shift. The scanning electron microscopy (SEM) images showed that the mean diameter of fiber decreased as the content of nanoclay increased. The mechanical tests showed that the tear strength force of neat nylon was 1.734 N, but this characteristic increased to 2.135 N for the sample with 0.5% modified nanoclay. The inulin adsorption efficiency of the Nylon 6/C20A 1.5% and Nylon 6/C20A 2% samples at 15 min was 75 and 74%, respectively. The adsorption capacity of Nylon 6/C20A 1.5% and Nylon 6/C20A 2% for methylene blue and methyl orange remained above 90% even after four adsorption cycles. In addition, non-woven fabrics present antibacterial activity against E. coli.

Generation of sub-150 fs, 10 W-class, pedestal-free 2.07 µm ultrashort pulses using a cascade compression system.

We report high-power pedestal-free ultrashort pulses in a cascade compression system. In the self-compression stage, the 2 µm ultrashort pulses with 123 fs duration and up to 21.7 W output power were obtained in a 0.3 m 50 µm core diameter fiber. It is the highest self-compressing power ever obtained in a silica fiber with an all-fiber 2 µm laser amplifier as the pump source. To obtain purer pedestal-eliminated pulses, we further increase the fiber length to 1 m to trigger the soliton self-frequency shifting (SSFS) effect. By employing an enhanced SSFS technique based on third-order dispersion (TOD) and filtering out the unshifted signal light, we finally achieved sub-150 fs, 10 W-class, 1.2-MW peak-power, pedestal-free 2.07 µm ultrashort pulses. This is also the highest, to the best of our knowledge, power and energy of Raman soliton obtained by SSFS in an ordinary silica fiber.

Genomic Characterization of Quality Wool Traits in Spanish Merino Sheep.

The native Spanish Merino breed was the founder of all the other Merino and Merino-derived breeds worldwide. Despite the fact that this breed was created and improved to produce the highest quality fine wool, the global wool market crisis led to the wholescale crossing of most of the herds with breeds for meat purposes. Nevertheless, there are still some purebred animals with a high potential for producing quality wool. The objective of this study was to characterize the current wool quality of the breed and identify genes associated with these parameters. To achieve this, over 12,800 records from the most representative animals of the breed (registered in the herd book) were analyzed using the Australian OFDA 2000 system, for parameters such as fiber diameter (FD), standard deviation (SD), coefficient of variation (CV), fibers over 15 microns (>15%), staple length (SL), and comfort factor (CRV). Additionally, animals with the most extreme FD values were whole-genome sequenced using NGS. Genome-wide association studies (GWAS) determined the association of 74 variants with the different traits studied, which were located in 70 different genes. Of these genes, EDN2, COL18A1, and LRP1B, associated with fibers over 15%, and FGF12 and ADAM17, associated with SL, play a key role in hair follicle growth and development. Our study reveals the great potential for recovering this breed for fine wool production, and identifies five candidate genes whose understanding may aid in that selection process.

Key genes and metabolites that regulate wool fibre diameter identified by combined transcriptome and metabolome analysis

BackgroundFibre diameter is an important economic trait of wool fibre. As the fibre diameter decreases, the economic value of wool increases. Therefore, understanding the mechanism of wool fibre diameter regulation is important in improving the value of wool. ResultsIn this study, we used non-targeted metabolome and reference transcriptome data to detect differences in metabolites and genes in groups of Alpine Merino sheep with different wool fibre diameter gradients, and integrated metabolome and transcriptome data to identify key genes and metabolites that regulate wool fibre diameter. We found 464 differentially abundant metabolites (DAMs) and 901 differentially expressed genes (DEGs) in four comparisons of groups with different wool fibre diameters. Approximately 25% of the differentially abundant metabolites were lipid and lipid-like molecules. These molecules were predicted to be associated with skin development and keratin filament by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analyses. Key genes, including COL5A2, COL5A3, CREB3L4, COL1A1, and SFRP4, were identified by gene set enrichment analysis. ConclusionsKey genes regulating wool fibre diameter were identified, the effects of lipid molecules on wool performance were investigated, and potential synergies between genes and metabolites were postulated, providing a theoretical framework for fine wool sheep breeding.