Seedling root system adaptation to water availability during maize domestication and global expansion.

The maize root system has been reshaped by indirect selection during global adaptation to new agricultural environments. In this study, we characterized the root systems of more than 9,000 global maize accessions and its wild relatives, defining the geographical signature and genomic basis of variation in seminal root number. We demonstrate that seminal root number has increased during maize domestication followed by a decrease in response to limited water availability in locally adapted varieties. By combining environmental and phenotypic association analyses with linkage mapping, we identified genes linking environmental variation and seminal root number. Functional characterization of the transcription factor ZmHb77 and in silico root modeling provides evidence that reshaping root system architecture by reducing the number of seminal roots and promoting lateral root density is beneficial for the resilience of maize seedlings to drought.

Viologen-based solution-processable ionic porous polymers for electrochromic applications.

Electrochromic porous thin films are promising for applications in smart windows and energy-efficient optical displays. However, their generally poor processing ability and excessive processing times remain grand challenges. Herein, we report the design and convenient synthesis of core-altered N-arylated viologens with aldehyde groups (πV-CHO) as new building blocks to prepare soluble, viologen-embedded ionic porous polymers. We also demonstrate that these polymers can be easily solution-processed by drop-coating to fabricate high-quality electrochromic films with tunable optoelectronic properties in a cost-effective fashion. The prepared films exhibit excellent electrochromic performance, including a low driving voltage (1.2-1.4 V), fast switching times (0.8-1.7 s), great coloration efficiency (73-268 cm2 C-1), remarkably high optical contrast up to 95.6%, long cycling stability, and tunable oxidation and reduction colors. This work sheds important light on a new molecular engineering approach to produce redox-active polymers with combined properties of intrinsic porosity, reversible and tunable redox activity, and solution processability. This provides the materials with an inherently broad utility in a variety of electrochemical devices for energy storage, sensors, and electronic applications.

Macrophage microRNA-146a is a central regulator of the foreign body response to biomaterial implants.

Host recognition and immune-mediated foreign body response (FBR) to biomaterials can adversely affect the functionality of implanted materials. To identify key targets underlying the generation of FBR, here we perform analysis of microRNAs (miR) and mRNAs responses to implanted biomaterials. We found that (a) miR-146a levels inversely affect macrophage accumulation, foreign body giant cell (FBGC) formation, and fibrosis in a murine implant model; (b) macrophage-derived miR-146a is a crucial regulator of the FBR and FBGC formation, as confirmed by global and cell-specific knockout of miR-146a; (c) miR-146a modulates genes related to inflammation, fibrosis, and mechanosensing; (d) miR-146a modulates tissue stiffness near the implant during FBR; and (e) miR-146a is linked to F-actin production and cellular traction force induction, which are vital for FBGC formation. These novel findings suggest that targeting macrophage miR-146a could be a selective strategy to inhibit FBR, potentially improving the biocompatibility of biomaterials.

PSAT1 enhances the efficacy of the prognosis estimation nomogram model in stage-based clear cell renal cell carcinoma.

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is associated with a high prevalence of cancer-related deaths. The survival rates of patients are significantly lower in late-stage ccRCC than in early-stage ccRCC, due to the spread and metastasis of late-stage ccRCC, surgery has not reached the goal of radical cure, and the effect of traditional radiotherapy and chemotherapy is poor. Thus, it is crucial to accurately assess the prognosis and provide personalized treatment at an early stage in ccRCC. This study aims to develop an efficient nomogram model for stratifying and predicting the survival of ccRCC patients based on tumor stage. METHODS: We first analyzed the microarray expression data of ccRCC patients from the Gene Expression Omnibus (GEO) database and categorized them into two groups based on the disease stage (early and late stage). Subsequently, the GEO2R tool was applied to screen out the genes that were highly expressed in all GEO datasets. Finally, the clinicopathological data of the two patient groups were obtained from The Cancer Genome Atlas (TCGA) database, and the differences were compared between groups. Survival analysis was performed to evaluate the prognostic value of candidate genes (PSAT1, PRAME, and KDELR3) in ccRCC patients. Based on the screened gene PSAT1 and clinical parameters that were significantly associated with patient prognosis, we established a new nomogram model, which was further optimized to a single clinical variable-based model. The expression level of PSAT1 in ccRCC tissues was further verified by qRT-PCR, Western blotting, and immunohistochemical analysis. RESULTS: The datasets GSE73731, GSE89563, and GSE150404 identified a total of 22, 89, and 120 over-expressed differentially expressed genes (DEGs), respectively. Among these profiles, there were three genes that appeared in all three datasets based on different stage groups. The overall survival (OS) of late-stage patients was significantly shorter than that of early-stage patients. Among the three candidate genes (PSAT1, PRAME, and KDELR3), PSAT1 was shown to be associated with the OS of patients with late-stage ccRCC. Multivariate Cox regression analysis showed that age, tumor grade, neoadjuvant therapy, and PSAT1 level were significantly associated with patient prognosis. The concordance indices were 0.758 and 0.725 for the 3-year and 5-year OS, respectively. The new model demonstrated superior discrimination and calibration compared with the single clinical variable model. The enhancer PSAT1 used in the new model was shown to be significantly overexpressed in tissues from patients with late-stage ccRCC, as demonstrated by the mRNA level, protein level, and pathological evaluation. CONCLUSION: The new prognostic prediction nomogram model of PSAT1 and clinicopathological variables combined was thus established, which may provide a new direction for individualized treatment for different-stage ccRCC patients.

Avocado-derived extracellular vesicles loaded with ginkgetin and berberine prevent inflammation and macrophage foam cell formation.

Atherosclerosis, a chronic inflammatory disease of aorta, remains the major cause of morbidity and mortality among cardiovascular disease patients. Macrophage foam cell formation and inflammation are critically involved in early stages of atherosclerosis, hence chemopreventive targeting of foam cell formation by nutraceuticals may be a promising approach to curbing the progression of atherosclerosis. However, many nutraceuticals including berberine and ginkgetin have low stability, tissue/cell penetration and bioavailability resulting in inadequate chemotherapeutic effects of these nutraceuticals. We have used avocado-derived extracellular vesicles (EV) isolated from avocado (EVAvo ) as a novel carrier of nutraceuticals, in a strategy to alleviate the build-up of macrophage foam cells and expression of inflammatory genes. Our key findings are: (i) Avocado is a natural source of plant-derived EVs as shown by the results from transmission electron microscopy, dynamic light scattering and NanoBrook Omni analysis and atomic force microscopy; (ii) EVAvo are taken up by macrophages, a critical cell type in atherosclerosis; (iii) EVAvo can be loaded with high amounts of ginkgetin and berberine; (iv) ginkgetin plus berberine-loaded EVAvo (EVAvo(B+G) ) suppress activation of NFκB and NLRP3, and inhibit expression of pro-inflammatory and atherogenic genes, specifically Cd36, Tnfα, Il1ß and Il6; (v) EVAvo(B+G) attenuate oxidized low-density lipoprotein (oxLDL)-induced macrophage foam cell formation and (vi) EVAvo(B+G) inhibit oxLDL uptake but not its cell surface binding during foam cell formation. Overall, our results suggest that using EVAvo as a natural carrier of nutraceuticals may improve strategies to curb the progression of atherosclerosis by limiting inflammation and pro-atherogenic responses.

Heritable microbiome variation is correlated with source environment in locally adapted maize varieties.

Beneficial interactions with microorganisms are pivotal for crop performance and resilience. However, it remains unclear how heritable the microbiome is with respect to the host plant genotype and to what extent host genetic mechanisms can modulate plant-microbiota interactions in the face of environmental stresses. Here we surveyed 3,168 root and rhizosphere microbiome samples from 129 accessions of locally adapted Zea, sourced from diverse habitats and grown under control and different stress conditions. We quantified stress treatment and host genotype effects on the microbiome. Plant genotype and source environment were predictive of microbiome abundance. Genome-wide association analysis identified host genetic variants linked to both rhizosphere microbiome abundance and source environment. We identified transposon insertions in a candidate gene linked to both the abundance of a keystone bacterium Massilia in our controlled experiments and total soil nitrogen in the source environment. Isolation and controlled inoculation of Massilia alone can contribute to root development, whole-plant biomass production and adaptation to low nitrogen availability. We conclude that locally adapted maize varieties exert patterns of genetic control on their root and rhizosphere microbiomes that follow variation in their home environments, consistent with a role in tolerance to prevailing stress.

Two High-Quality Cygnus Genome Assemblies Reveal Genomic Variations Associated with Plumage Color.

As an exemplary model for examining molecular mechanisms responsible for extreme phenotypic variations, plumage color has garnered significant interest. The Cygnus genus features two species, Cygnus olor and Cygnus atratus, that exhibit striking disparities in plumage color. However, the molecular foundation for this differentiation has remained elusive. Herein, we present two high-quality genomes for C. olor and C. atratus, procured using the Illumina and Nanopore technologies. The assembled genome of C. olor was 1.12 Gb in size with a contig N50 of 26.82 Mb, while its counterpart was 1.13 Gb in size with a contig N50 of 21.91 Mb. A comparative analysis unveiled three genes (TYR, SLC45A2, and SLC7A11) with structural variants in the melanogenic pathway. Notably, we also identified a novel gene, PWWP domain containing 2A (PWWP2A), that is related to plumage color, for the first time. Using targeted gene modification analysis, we demonstrated the potential genetic effect of the PWWP2A variant on pigment gene expression and melanin production. Finally, our findings offer insight into the intricate pattern of pigmentation and the role of polygenes in birds. Furthermore, these two high-quality genome references provide a comprehensive resource and perspective for comparative functional and genetic studies of evolution within the Cygnus genus.

Unveiling the common loci for six body measurement traits in Chinese Wenshan cattle.

Introduction: Body measurement traits are integral in cattle production, serving as pivotal criteria for breeding selection. Wenshan cattle, a local breed in China's Yunnan province, exhibit remarkable genetic diversity. However, the molecular mechanisms regulating body measurement traits in Wenshan cattle remain unexplored. Methods: In this study, we performed a genome-wide association method to identify genetic architecture for body height body length hip height back height (BAH), waist height and ischial tuberosity height using the Bovine 50 K single nucleotide polymorphism Array in 1060 Wenshan cattles. Results: This analysis reveals 8 significant SNPs identified through the mixed linear model (MLM), with 6 SNPs are associated with multiple traits and 4 SNPs are associated with all 6 traits. Furthermore, we pinpoint 21 candidate genes located in proximity to or within these significant SNPs. Among them, Scarb1, acetoacetyl-CoA synthetase and HIVEP3 were implicated in bone formation and rarely encountered in livestock body measurement traits, emerge as potential candidate genes regulating body measurement traits in Wenshan cattle. Discussion: This investigation provides valuable insights into the genetic mechanisms underpinning body measurement traits in this unique cattle breed, paving the way for further research in this domain.

Comparative Analysis of PRNP Gene Indel Polymorphism and Expression among Zhongdian Yellow Cattle, Zhongdian Yak, and Their Hybrids.

Bovine spongiform encephalopathy (BSE) is a fatal disease in cattle caused by misfolded prion proteins and linked to indel polymorphisms in the promoter and intron 1 of the PRNP gene. The aim of this study was to determine the allele, genotype, and haplotype frequencies of PRNP indel polymorphisms and to investigate the effect of PRNP gene expressions of 23 bp and 12 bp indels via polymerase chain reaction (PCR) in Zhongdian Yak (Bos-grunniens) (YK), Zhongdian Yellow cattle (Bos-taurus) (YC), and Zhongdian Yakow (Bos-primigenius taurus × Bos-grunniens) (PK). Resultant high allelic frequencies were found in 23- and 12+, while haplotype frequencies were very low in 23+/12 in YK, YC, and PK. PRNP expression was higher in the +-/-- diplotype of the PK and (mean ± SE) was 3.6578 ± 1.85964. Furthermore, two variable sites were investigated-a 23 bp indel polymorphism holding AP1 binding site and a 12 bp indel polymorphism holding SP1 binding site. Additionally, reporter gene assays revealed a link between two proposed transcription factors and lower expression levels of the +/+ allele compared with the -/- allele. The expression level of PRNP was shown to be dependent on two indel polymorphisms in the bovine PRNP promoter, which includes binding sites for RP58 and SP1 transcription factors. These findings raised the possibility that the PRNP genotype may contribute to the high variation in PRNP expression.

[Finite element analysis for predicting osteonecrosis of the femoral head collapse based on the preserved angles].

Objective: To establish finite element models of different preserved angles of osteonecrosis of the femoral head (ONFH) for the biomechanical analysis, and to provide mechanical evidence for predicting the risk of ONFH collapse with anterior preserved angle (APA) and lateral preserved angle (LPA). Methods: A healthy adult was selected as the study object, and the CT data of the left femoral head was acquired and imported into Mimics 21.0 software to reconstruct a complete proximal femur model and construct 3 models of necrotic area with equal volume and different morphology, all models were imported into Solidworks 2022 software to construct 21 finite element models of ONFH with LPA of 45°, 50°, 55°, 60°, 65°, 70°, and 75° when APA was 45°, respectively, and 21 finite element models of ONFH with APA of 45°, 50°, 55°, 60°, 65°, 70°, 75° when LPA was 45°, respectively. According to the physiological load condition of the femoral head, the distal femur was completely fixed, and a force with an angle of 25°, downward direction, and a magnitude of 3.5 times the subject's body mass was applied to the weight-bearing area of the femoral head surface. The maximum Von Mises stress of the surface of the femoral head and the necrotic area and the maximum displacement of the weight-bearing area of the femoral head were calculated and observed by Abaqus 2021 software. Results: The finite element models of ONFH were basically consistent with biomechanics of ONFH. Under the same loading condition, there was stress concentration around the necrotic area in the 42 ONFH models with different preserved angles composed of 3 necrotic areas with equal volume and different morphology. When APA was 60°, the maximum Von Mises stress of the surface of the femoral head and the necrotic area and the maximum displacement of the weight-bearing area of the femoral head of the ONFH models with LPA<60° were significantly higher than those of the models with LPA≥60° ( P<0.05); there was no significant difference in each index among the ONFH models with LPA≥60° ( P>0.05). When LPA was 60°, each index of the ONFH models with APA<60° were significantly higher than those of the models with APA≥60° ( P<0.05); there was no significant difference in each index among the ONFH models with APA≥60° ( P>0.05). Conclusion: From the perspective of biomechanics, when a preserved angle of ONFH is less than its critical value, the stress concentration phenomenon in the femoral head is more pronounced, suggesting that the necrotic femoral head may have a higher risk of collapse in this state.

Effect of whole body vibration therapy in the rat model of steroid-induced osteonecrosis of the femoral head.

Background: Steroid-induced Osteonecrosis of the Femoral Head (SIONFH) is a skeletal disease with a high incidence and a poor prognosis. Whole body vibration therapy (WBVT), a new type of physical training, is known to promote bone formation. However, it remains unclear whether WBVT has a therapeutic effect on SIONFH. Materials and methods: Thirty adult male and female Sprague-Dawley (SD) rats were selected and randomly assigned to three experimental groups: the control group, the model group, and the mechanical vibration group, respectively. SIONFH induction was achieved through the combined administration of lipopolysaccharides (LPS) and methylprednisolone sodium succinate for injection (MPS). The femoral head samples underwent hematoxylin and eosin (H&E) staining to visualize tissue structures. Structural parameters of the region of interest (ROI) were compared using Micro-CT analysis. Immunohistochemistry was employed to assess the expression levels of Piezo1, BMP2, RUNX2, HIF-1, VEGF, CD31, while immunofluorescence was used to examine CD31 and Emcn expression levels. Results: The H&E staining results revealed a notable improvement in the ratio of empty lacuna in various groups following WBVT intervention. Immunohistochemical analysis showed that the expression levels of Piezo1, BMP2, RUNX2, HIF-1, VEGF, and CD31 in the WBVT group exhibited significant differences when compared to the Model group (p < 0.05). Additionally, immunofluorescence analysis demonstrated statistically significant differences in CD31 and Emcn expression levels between the WBVT group and the Model group (p < 0.05). Conclusion: WBVT upregulates Piezo1 to promote osteogenic differentiation, potentially by enhancing the HIF-1α/VEGF axis and regulating H-vessel angiogenesis through the activation of the Piezo1 ion channel. This mechanism may lead to improved blood flow supply and enhanced osteogenic differentiation within the femoral head.

Construction of Naphthalene Diimide Derived Nanostructured Cathodes through Self-Assembly for High-Performance Sodium-Organic Batteries.

Organic nanostructured electrodes are very attractive for next-generation sodium-ion batteries. Their great advantages in improved electron and ion transport and more exposed redox-active sites would lead to a higher actual capacity and enhanced rate performance. However, facile and cost-effective methods for the fabrication of nanostructured organic electrodes are still highly challenging and very rare. In this work, we utilize a bioinspired self-assembly strategy to fabricate nanostructured cathodes based on a rationally designed N-hydroxy naphthalene imide sodium salt (NDI-ONa) for high-performance sodium-organic batteries. Such a well-organized nanostructure can greatly enhance both ion and electron transport. When used as cathode for sodium-organic batteries, it provides among the best battery performances, such as high capacity (171 mA h g-1 at 0.05 A g-1), excellent rate performance (153 mA h g-1 at 5.0 A g-1), and ultralong cycling life (93% capacity retention after 20000 cycles at 3.0 A g-1). Even at low temperature or without a conductive additive, it can also perform well. It is believed that self-assembly is a very powerful strategy to construct high-performance nanostructured electrodes.

Mechanical properties of trabeculae and osteocyte morphology change significantly in different areas of the necrotic femoral head.

Background: Osteonecrosis of the femoral head is a complex hip ailment. The precise changes in bone tissue during the disease's onset remain unclear. It is vital to assess both the quantity and quality of the trabecular state in a necrotic femoral head. Aim: This study aims to identify and compare the ultrastructural changes in osteocyte morphology and nanomechanical characteristics within various regions of necrotic femoral heads. Methods: Between December 2016 and May 2023, we gathered ten necrotic femoral heads from patients and five femoral heads from cadavers. The samples from the necrotic femoral heads were categorized into three areas: necrotic, sclerotic, and normal. Our assessment methods encompassed hematoxylin and eosin staining, sclerostin (SOST) immunohistochemistry, micro-computed tomography, nanoindentation, and acid-etched scanning electron microscopy. These techniques enabled us to examine the SOST expression, trabecular microstructure, micromechanical properties of trabeculae, and modifications in osteocyte morphology at the ultrastructural level. Results: The protein level of SOST was found to be lower in the sclerotic area. In the necrotic area, decreased values of bone volume fraction, trabecular thickness, and trabecular number and an increased value of trabecular separation were found. Conversely, in the sclerotic area, higher mean values of bone volume fraction, trabecular number, and trabecular thickness and lower trabecular separation indicated significant changes in the structural characteristics of trabeculae. Compared with the healthy area, the elastic modulus and hardness in the sclerotic area were significantly higher than those in the necrotic, normal, and control areas, while those in necrotic areas were significantly lower than those in the healthy area. The number of osteocytes tended to increase in the sclerotic area with more canalicular cells compared to the healthy area and control group. Conclusion: These results imply that the stress distribution within the sclerotic area could potentially lead to enhanced trabecular quality and quantity. This effect is also reflected in the increased count of osteocytes and their canaliculars. It is plausible that the sclerotic trabecular bone plays a pivotal role in the repair of necrotic femoral heads.

Lateral classification system predicts the collapse of JIC type C1 nontraumatic osteonecrosis of the femoral head: a retrospective study.

PURPOSES: The aim of this study was to construct a lateral classification system for nontraumatic osteonecrosis of femoral head (NONFH) through three-dimensional reconstruction of the necrotic area to assist in evaluating the prognosis of patients with JIC type C1. METHODS: Retrospective analysis of patients with JIC type C1 NONFH from January 2018 to December 2020. All patients were followed up for more than 3.5 years. The patients were divided into collapse group and non-collapse group according to whether the femoral head collapsed during the follow-up.Lateral classification system for femoral head necrosis is constructed through three-dimensional reconstruction of the necrotic area.Comparison of lateral classification system,midsagittal necrosis angle(MNA)and general data between the two groups.Furthermore, ROC curve analysis and survival analysis were performed. RESULTS: 318 patients were included in this study.There was a significant difference between the two groups in the lateral classification system (P < 0.05). In addition, the MNA in the collapsed group was significantly greater than that in the non-collapse group(P < 0.05). As revealed by the results of ROC analysis, the cutoff point of MNA was 104.5° (P < 0.05).According to the survivorship analysis, the mean survival time of the hips of patients with MNA less than 104.5°was greater than that of patients with MNA over 104.5° (P < 0.05). The survival rates of 3.5 years femoral head were 45.8%, 33.7%, 14.8%, 93.0%, and 100% for lateral classification system 1, 2, 3, 4, and 5, respectively. CONCLUSION: Necrosis involving the anterior aspect of the femoral head is an important risk factor for collapse. The Lateral classification system can effectively predict the femoral head collapse in JIC C1 type NONFH patients, supplementing the deficiency of JIC classification in evaluating the front of the femoral head.

Assessing the impact of the 2018 tetanus guidelines on knowledge and practices of emergency physicians in trauma patients: a national survey study.

Background: Tetanus remains a significant public health issue in China, with the approach of anti-tetanus prophylaxis in the emergency department resulting in both overuse, particularly of human tetanus immune globulin (TIG), and underuse with the tetanus vaccine. This is largely due to the absence of updated guidelines on tetanus prophylaxis before 2018. Our study aimed to evaluate the effects of the 2018 Chinese tetanus guidelines on the knowledge and practices of emergency physicians about tetanus prevention in trauma patients. Methods: From November 2019 to April 2020, we conducted a web-based survey involving 499 emergency physicians. The survey included a questionnaire covering knowledge, attitudes, and practices related to tetanus. We assessed the influence of the 2018 tetanus guidelines on the knowledge and practices of emergency physicians related to tetanus prevention for patients with trauma using multiple regression analysis. Results: The survey results showed that only 45.3% of the participants had received formal training on tetanus immunization, despite 53.3% reporting the availability of tetanus vaccines at their institutions. Physicians typically prescribed tetanus antitoxin or human TIG instead of tetanus toxoid (TT) to treat injuries, regardless of the patient's TT vaccination history. Among the respondents, those who were aware of the 2018 tetanus guidelines had higher mean scores on the general knowledge, risk knowledge, and treatment knowledge scales, with increases of 6%, 13%, and 9%, respectively, compared to those who were unaware of the guidelines. Awareness of the 2018 tetanus guidelines was associated with a high level of knowledge, as indicated by the general knowledge score, recommendation knowledge score, and total knowledge score, after adjusting for the effects of all variables on the knowledge, attitudes, and practices of the participants. A high level of education was also associated with a high level of knowledge indicated by the recommendation knowledge score and total knowledge score. Conclusions: Our study highlights a substantial gap in the attitudes, knowledge, and practices of emergency physicians in China regarding tetanus immunization. The results suggest an urgent need to promote the Chinese Expert Consensus Guidelines on tetanus to improve emergency physicians' knowledge and competence in tetanus prophylaxis. The findings underscore the importance of enhancing physicians' awareness of the latest guidelines to ensure appropriate and effective treatment for patients with tetanus-prone injuries.

Modified Viologen- and Carbonylpyridinium-Based Electrodes for Organic Batteries.

Efficient electrochemical energy storage has been identified as one of the most pressing needs for a sustainable energy economy. Inorganic battery materials have traditionally been the center of attention, with the current state-of-the-art device being the lithium-ion battery. Recent pursuits have led to organic materials for their beneficial chemistry and properties, but suitable materials for organic batteries are still few and far between. This Spotlight on Applications highlights two intriguing pyridinium-based organic materials, modified viologens and carbonylpyridiniums, that have both been successfully employed in electrode materials for solid-state Li-ion-type organic batteries (LOBs). We first provide an overview of the inherent electronic properties of each building block and how they can effectively be modified while maintaining or enhancing their desirable electrochemical properties for practical applications. We then describe a range of different material designs for a battery context and their application in various organic device settings, with some examples showing competitive performance with traditional Li-ion batteries.

Exploring the Impact of Ampelopsis Grossedentata Flavonoids on Growth Performance, Ruminal Microbiota, and Plasma Physiology and Biochemistry of Kids.

This study was conducted to evaluate the influences of supplementing Ampelopsis grossedentata flavonoids (AGF) on the rumen bacterial microbiome, plasma physiology and biochemistry, and growth performance of goats. Twenty-four Nubian kids were randomly allocated to three dietary treatments: the control (CON, basal diet), the 1.0 g/kg AGF treatment (AGF), and the 12.5 mg/kg monensin treatment (MN). This trial consisted of 10 days for adaptation and 90 days for data and sample collection. The results reveal that Bacteroidetes, Firmicutes, and Proteobacteria are the dominant phyla in kids' rumen. Compared with the CON group, the alpha diversity in the MN and AGF groups significantly increased (p < 0.01). Beta-diversity shows that rumen microbial composition is more similar in the MN and AGF groups. LEfSe analysis shows that Prevotella_1 in the AGF group were significantly higher than those in the MN and CON group. The high-density lipoprotein cholesterol and glucose levels in the AGF group were significantly higher than those in the CON group (p < 0.05), whereas the low-density lipoprotein cholesterol, glutamic-pyruvic transaminase, and alkaline phosphatase levels exhibited the opposite trend. The average daily gains in the AGF and MN groups significantly increased, while the feed-to-gain ratios were significantly decreased (p < 0.05). The results suggest that adding AGF to the diet improves microbial composition and has important implications for studying juvenile livestock growth and improving economic benefits.

Micromechanical characterizations and viscoelastic modeling reveal elastic and viscoelastic heterogeneities in ovarian tissue and the significant viscoelastic contribution to the apparent elastic modulus determined by AFM indentation.

Ovarian follicles develop in a highly regulated mechanical microenvironment and disruptions to the microenvironment may cause infertility. However, the viscoelastic properties of the ovarian tissue are not well studied. Here, we characterize both the elastic and viscoelastic properties of ovarian tissue from both reproductively older and younger domestic cats using atomic force microscopy (AFM) indentation and viscoelastic models of stress relaxation. Importantly, our analyses reveal the apparent elastic modulus obtained from the conventional AFM indentation measurement is significantly higher than the intrinsic elastic modulus and insignificantly different from the equivalent elastic modulus that is the summation of the intrinsic elastic modulus and the viscoelastic contribution to modulus at time 0. Interestingly, the ovarian cortex of both reproductive age groups has a higher apparent/intrinsic modulus than that of the medulla. Furthermore, two different kinetics of stress relaxation are identified with rate constants of ∼1 s and ∼20-40 s, respectively. Moreover, the rate constant of the slow kinetics is significantly different between the cortex and medulla in the reproductively older ovaries. Finally, these mechanical heterogeneities appear to follow the heterogeneous distribution of hyaluronic acid (HA) in the ovary. These findings may be invaluable to the development of biomimetic follicle culture for treating infertility. STATEMENT OF SIGNIFICANCE: This study investigates not only elastic but also the viscoelastic heterogeneity in both reproductively younger and older ovarian tissues for the first time. Further, by combining AFM indentation measurement and viscoelastic modeling, we show the apparent elastic modulus conventionally reported in the literature for AFM indentation measurement is the summation of the intrinsic elastic modulus and a significant viscoelastic contribution to the modulus at time 0. This is an important consideration for others who use this method to quantify biomaterial properties. In addition, the possible connection between the mechanical and compositional heterogeneities is explored. These findings may be invaluable for designing biomaterials to recapitulate the mechanical environment of the ovary and possibly many other organs for biomimetic tissue engineering.