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Irritable bowel syndrome (IBS) is a common chronic gastrointestinal disorder, but its diagnosis and treatment remain obscure. Non-coding RNAs (ncRNAs), as potential biomarkers, have attracted increasing attention in digestive diseases. Here, we present a comprehensive research status, development trends, and valuable insights in this subject area. The literature search was performed using Web of Science Core Collection. VOSviewer 1.6.20, Citespace 6.2.R4, and Microsoft Excel 2021 were used for bibliometric analysis. A total of 124 articles were included in the analysis. Overall, publication patterns fluctuated. Globally, People's Republic of China, the USA, and Germany were the top three contributors of publications. Guangzhou University of Chinese Medicine, University of California, Mayo Clinic, and University of California, Los Angeles contributed the highest number of publications. The pathways and specific mechanisms by which ncRNAs regulate transcription and translation and thus regulate the pathophysiological processes of IBS are the main research hotspots in this field. We found that microRNA (miRNAs) are intricately involved in the regulation of key pathologies such as viscera sensitivity, intestinal permeability, intestinal mucosal barrier, immunoinflammatory response, and brain-gut axis in the IBS, and these topics have garnered significant attention in research community. Notably, microecological disorders are also associated with IBS pathogenesis, and ncRNA may play an important role in the interactions between host and intestinal flora. This is the first bibliometric study to comprehensively summarize the research hotspots and trends related to IBS and ncRNAs (especially miRNAs). Our findings will help understand the role of ncRNAs in IBS and provide guidance to future studies. [ABSTRACT FROM AUTHOR]

Chiral metamaterials have been proven to possess many appealing mechanical phenomena, such as negative Poisson's ratio, high-impact resistance, and energy absorption. This work extends the applications of chiral metamaterials to underwater sound insulation. Various chiral metamaterials with low acoustic impedance and proper stiffness are inversely designed using the topology optimization scheme. Low acoustic impedance enables the metamaterials to have a high and broadband sound transmission loss (STL), while proper stiffness guarantees its robust acoustic performance under a hydrostatic pressure. As proof-of-concept demonstrations, two specimens are fabricated and tested in a water-filled impedance tube. Experimental results show that, on average, over 95% incident sound energy can be isolated by the specimens in a broad frequency range from 1 kHz to 5 kHz, while the sound insulation performance keeps stable under a certain hydrostatic pressure. This work may provide new insights for chiral metamaterials into the underwater applications with sound insulation. [ABSTRACT FROM AUTHOR]

Elastic metamaterials are popularly sought to realize numerous special functions such as vibration control and wave manipulation among which sound absorption is a typical task fulfilled by acoustic metamaterials. Inverse designing metamaterials with machine learning approaches has been under the spotlight thanks to the data-driven experience-free advantages and become one of the important design paradigms. Nevertheless, the existing works mostly concentrate on validating the reproduction accuracy of the neural networks on trained data and very few have explored their ability on designing for enhanced properties. To this end, our work studies the competence of the proposed inverse design framework in enhancing the acoustic performance of a three-dimensional mixed-size cavity-based waterborne sound absorptive metamaterial. With forward and inverse networks in the framework, the target sound absorption spectra (100-10000 Hz) are taken as inputs into the inverse network during training and a corresponding structure is output with the best matching spectra which is subsequently fed into the forward network for acoustic property evaluation and loss calculation. The trained forward network is shown to possess excellent generalization capabilities by highly accurately predicting for structures with “unseen” beyond-range parameters compared to the training set. Most importantly, the inverse network is delightfully capable of spontaneously adopting beyond-range structural parameters to ensure meeting the acoustic target whose mean sound absorption coefficient is higher than any of the data in the training set, hence inverse designing for enhanced performance. The inverse design accuracy is dramatically improved from only 9.2% of mean squared errors being <0.0001 to 99.6% with beyond-range exploration. A case study is presented to demonstrate the significant difference beyond-range exploration makes for inverse designing aiming at enhanced performance. It is hoped that this work will serve as an inspiration for the design and optimization of elastic metamaterials with enhanced performance for future work. [ABSTRACT FROM AUTHOR]

The eastern oyster Crassostrea virginica is a major aquaculture species for the USA. The sustainable development of eastern oyster aquaculture depends upon the continued improvement of cultured stocks through advanced breeding technologies. The Eastern Oyster Breeding Consortium (EOBC) was formed to advance the genetics and breeding of the eastern oyster. To facilitate efficient genotyping needed for genomic studies and selection, the consortium developed two single-nucleotide polymorphism (SNP) arrays for the eastern oyster: one screening array with 566K SNPs and one breeders' array with 66K SNPs. The 566K screening array was developed based on whole-genome resequencing data from 292 oysters from Atlantic and Gulf of Mexico populations; it contains 566,262 SNPs including 47K from protein-coding genes with a marker conversion rate of 48.34%. The 66K array was developed using best-performing SNPs from the screening array, which contained 65,893 oyster SNPs including 22,984 genic markers with a calling rate of 99.34%, a concordance rate of 99.81%, and a much-improved marker conversion rate of 92.04%. Null alleles attributable to large indels were found in 13.1% of the SNPs, suggesting that copy number variation is pervasive. Both arrays provided easy identification and separation of selected stocks from wild progenitor populations. The arrays contain 31 mitochondrial SNPs that allowed unambiguous identification of Gulf mitochondrial genotypes in some Atlantic populations. The arrays also contain 756 probes from 13 oyster and human pathogens for possible detection. Our results show that marker conversion rate is low in high polymorphism species and that the two-step process of array development can greatly improve array performance. The two arrays will advance genomic research and accelerate genetic improvement of the eastern oyster by delineating genetic architecture of production traits and enabling genomic selection. The arrays also may be used to monitor pedigree and inbreeding, identify selected stocks and their introgression into wild populations, and assess the success of oyster restoration. [ABSTRACT FROM AUTHOR]

Based on the analysis of the radial stress distribution in surrounding rocks of tunnel, different asymmetric radial stresses were loaded, which can more truly reflect the stress state of surrounding rocks of tunnel. The stress state and boundary conditions of representative surrounding rock element were simulated by sandstone in this study. The mechanical response and fracture mode transformation were studied. The experimental results showed that as the depth of surrounding rocks from the free surface of tunnel increased, the properties of surrounding rocks showed the characteristics of transition from brittleness to ductility. The strengths of sandstone specimens gradually increased with the increase of the depth, and a power function can well characterize the relationship between the strength and the depth. The fracture modes of sandstone specimens transformed from tensile splitting fracture to tensile-shear complex fracture, and finally to shear fracture with the increase of the depth, which was mainly caused by the asymmetric radial stresses. According to the characteristics of fracture modes under different asymmetric radial stress conditions, four types of failure zones in the radial direction of surrounding rocks can be divided, i.e., tensile splitting failure zone, tensile-shear complex failure zone, shear failure zone, and slight shear failure zone. The shear fracture in deep surrounding rocks and the accompanying large deformation of surrounding rocks should be paid more attention in the support of tunnel. In addition, the accuracy of time-failure model was verified, and it can accurately predict the time needed for rock failure. [ABSTRACT FROM AUTHOR]

Subsurface rocks are in the in situ stress state prior to drilling. The original and intact borehole subjected to stress redistribution can be deformed during field operations, and elliptical boreholes will be generated. Most laboratory scale hydraulic fracturing experimental specimens were predrilled in the center without considering lateral and axial pressure. In order to investigate the hydraulic fracturing characteristics of boreholes with non-circular appearance commonly seen in the field, hydraulic fracturing experiments were performed on boreholes with elliptical morphology. These experiments provide a comparison of elliptical and circular boreholes, and indicated that the horizontal in situ stress difference and borehole shape affect the breakdown pressure together. When the horizontal stress difference exists, the breakdown pressure reduces with the increase of the short-axis of elliptical boreholes. At zero horizontal stress difference, the situation is just the opposite. The analytic solutions of the stress fields near the elliptical borehole were obtained by employing the complex variable function. The fracture initiation conforms to the maximum tensile stress criterion. Whether the borehole is elliptical or circular, the damage process during hydraulic fracturing will cause fractures to eventually curve to the major stress direction. [ABSTRACT FROM AUTHOR]

Background: Both thyroid-stimulating immunoglobulins immunoassay (TSI IA) and thyrotrophin receptor antibody immunoassay (TRAb IA) are commonly used for the diagnosis of Graves' disease (GD). The aim of the present study was to compare the clinical diagnostic performance of these two methods. Methods: Sera were obtained from 1103 subjects presenting a variety of clinical conditions from three centers: 100 subjects with untreated GD, 200 with treated GD, 62 with autoimmune thyroid disease(AIT), 216 with other thyroid diseases (OTHER-T), 214 with non-thyroid autoimmune diseases (NTAD), 191 with other diseases (OD), and 120 healthy subjects (HS). Both TSI and TRAb IAs were performed for all 1013 serum samples. Bioassay was performed for 86 samples whose TSI results were inconsistent the TRAb assay results. Results: Comparing untreated GD patients with the control groups (AIT, NTAD, OTHER-T, OD, and HS) resulted in an area under the curve (AUC) of 0.992 for the TSI IA and 0.989 for the TRAb IA with no statistically significant difference observed between these AUC values (P = 0.2733). The best TSI CDP (clinical decision point) value was 0.42 IU/L. The differences in sensitivity (100% vs. 95%, P = 0.7991) and specificity (97.1% vs. 97.6%, P = 0.9426) between the TSI and TRAb IA were not statistically significant. TSI IA had a higher agreement with the TSI bioassay than TRAb IA. Conclusion: The clinical diagnostic performance of the TSI IA for diagnosing Graves' disease was very similar to that of the TRAb IA. TSI IA can be used to diagnose GD in the Chinese. [ABSTRACT FROM AUTHOR]

In underground coal mining, coal failure generally occurs due to the relatively weak strength of the coal and the high applied mining-induced stresses. The outer complex geological conditions (i.e., tectonic structure and water intrusion) and internal structural anisotropy of the coal introduce uncertainty in predicting its mechanical properties and failure behavior. In this study, laboratory investigations of the mechanical properties and failure behavior of dry and water-saturated anisotropic coal samples subjected to different true-triaxial loading stresses were conducted. The effects of water weakening, intermediate stress, and structural anisotropy on the mechanical properties and failure behavior of the coal were systematically studied. The results indicate that the presence of water significantly reduced the strength, elastic modulus, and strength anisotropy of the coal. The maximum stress at failure first increased and then decreased with increasing intermediate stress. The residual strength-to-peak strength ratios and failure plane angles of the coal showed a linear increase with increasing intermediate stress. When the coal samples were loaded in the bedding plane direction, the brittleness of the coal was higher than when they were loaded in the other two cleat plane directions. In addition, when the coal samples were loaded in the butt cleat plane direction, the brittleness of the coal decreased with increasing intermediate stress. Two typical failure modes of the dry and water-saturated coal samples were observed: shear and mixed splitting and shear failures. The dominant failure mode of the coal also varied with the loading direction relative to the weakness planes, which could be well recognized and predicted by the acoustic emission (AE) characteristic curves. To further reveal the fracture mechanism, the microcrack patterns of the coal were further identified based on the AE parameters. [ABSTRACT FROM AUTHOR]

Black basses (genus Micropterus) are apex predators in North American streams, rivers, and lakes and important game fishes. Translocation and introductions for angling, accompanied by intrinsically weak genetic barriers, have led to widespread introgressive hybridization and genetic swamping. Species-diagnostic (fixed allele) SNP markers have been utilized successfully in salmonids to monitor hybridization and genetic integrity. Here, we developed similar resources for black basses through initial genotyping-by-sequencing, followed by validation in additional samples using two panels of 64 SNPs. Results from > 1300 genotyped bass indicated that the developed panels robustly and clearly delineate fifteen species and their hybrids among black basses. The panels represent a flexible, rapid turnaround (~ 1 day), and cost-effective tool that should augment ongoing efforts toward black bass conservation and management. [ABSTRACT FROM AUTHOR]

The widespread introduction of Largemouth Bass (Micropterus salmoides) and Florida Bass (M. floridanus) to establish sport fisheries represents a significant conservation concern given their role as apex predators and their ability to alter community diversity and species abundance. In regions like southern Africa, which has both high levels of aquatic endemism and imperilment, limiting the spread of invasive predators is a primary goal of current alien species legislation. Here, we applied two panels of species-diagnostic SNPs for a total of 60 markers to map the distribution of Largemouth Bass, Florida Bass, and their hybrids in 13 southern African water bodies. Using Bayesian clustering algorithms we documented the introgression of Florida Bass alleles across a broad geographic range, from the Cape Floristic region of South Africa to Mozambique. Several populations previously considered pure Largemouth Bass based on mitochondrial DNA sequences were found to consist exclusively of hybrids. Samples collected from Lake Chicamba, which was initially established with pure Largemouth Bass, are now almost exclusively comprised of Florida Bass alleles (89.3 % Florida Bass). The estimated hybrid class of sampled fish (e.g., F1 hybrid, pure Largemouth Bass, pure Florida Bass) showed that with few exceptions, populations were dominated by a single hybrid class. The present work provides enhanced resolution of the distribution and dynamics of Florida Bass, Largemouth Bass, and their hybrids in southern Africa. [ABSTRACT FROM AUTHOR]

Culture of the eastern oyster (Crassostrea virginica) is rapidly expanding. Combined with their continuing role as an environmental sentinel species and ecological model, this trend necessitates improved molecular tools for breeding and selection, as well as population assessment and genetic conservation. Here, we describe the development and validation of two panels of 58 single nucleotide polymorphism markers (SNPs) for the species. Population analyses revealed three distinct populations, based on FST values and STRUCTURE, among wild oysters sampled from Delaware Bay (1), northwest Florida (2), Alabama (2), Louisiana (2), and the Texas Gulf Coast (3), consistent with previous microsatellite and mtDNA analyses. In addition, utilizing the developed panels for parentage assignment in cultured oysters (Rutgers, New Jersey) resulted in a highly accurate identification of parent pairs (99.37%). The SNP markers could, furthermore, clearly discriminate between hatchery stocks and wild-sourced individuals. The developed SNP panels may serve as an important tool for more rapid and affordable genetic analyses in eastern oyster. [ABSTRACT FROM AUTHOR]

Phononic crystals (PCs) are functional materials with periodic structures and elastic wave (vibration) band gaps, where propagation of vibrations with frequencies within band gaps is forbidden. PCs with finite periods can restrain the propagation of vibrations with frequencies in band gaps and thus has vibration attenuation property. Worldwide, many institutions and researchers are engaged in the research of PCs, however, studies on the vibration attenuation property of PCs are still limited. In this paper, we report our study of band gaps and vibration attenuation properties of 1) a simplified PC—periodic mass-spring structures, 2) longitudinal vibration of one-dimensional (1D-), 2D-, 3D-PCs, and 3) the flexural vibration of 1D-and 2D-PCs. These studies provide a foundation for the applications of PCs in vibration attenuation. [ABSTRACT FROM AUTHOR]

Evapotranspiration (ET) is a key variable in hydrologic cycle that directly affects the redistribution of precipitation and surface balance. ET measurements with high temporal resolution are required for coupling with models of highly dynamic processes, e.g., hydrological and land surface processes. The Haihe River Basin is the focus of China's industrial base and it is one of the three major grain-producing regions within the country. However, this area is facing serious water resource shortages and water pollution problems. The present study used geostationary satellite remote sensing data, in situ meteorological observations, and the surface energy balance system (SEBS) model with a new kB−1 parameterization to estimate 3-hourly and daily energy and water fluxes in the Haihe River Basin. The results of the SEBS model were validated with point-scale data from five observation flux towers. Validation showed that 3-hourly and daily ET derived from the SEBS model performed well (R2 = 0.67, mean bias = 0.027 mm/h, RMSE = 0.1 mm/h). Moreover, factors influencing ET were also identified based on the results of this study. ET varies with land cover type and physical and chemical properties of the underlying surface. Furthermore, ET is also controlled by water availability, radiation, and other atmospheric conditions. It was found that ET had strong correlation with the normalized difference vegetation index (NDVI). Specifically, daily ET fluctuated with the NDVI when the NDVI was <0.29, and ET increased rapidly as the NDVI increased from 0.29 to 0.81. For NDVI values >0.81, indicating a state of saturation, the rate of increase of ET slowed. This research produced reliable information that could assist in sustainable management of the water resources and in improved understanding of the hydrologic cycle of the Haihe River Basin. [ABSTRACT FROM AUTHOR]

Effective absorption of low-frequency waterborne sound with subwavelength absorbers has always been a challenging work. In this paper, we derive two theoretical requirements for broadband perfect absorption of low-frequency waterborne sound by ultrathin acoustic metasurface under a finite-thickness steel plate followed by semi-infinite air. Based on the theoretical requirements, an acoustic metasurface, a rubber layer embedded periodically with cavities, is inversely designed to achieve perfect absorption at 500 Hz. The metasurface is as thin as 1% of the working wavelength and maintains a substantially high absorptance over a relatively broad bandwidth. The perfect absorption peak is attributed to the overall resonance mode of the metasurface/steel plate system. Besides, high absorption can still be achieved even if the loss factor of the given rubber material cannot meet the ideal requirement. Finally, a strategy to utilize the inherent frequency-dependent characteristics of dynamic parameters of rubber material is suggested to achieve an ultra-broadband perfect absorption. When the frequency-dependent characteristics of the given rubber matrix cannot meet the theoretical requirements, a broadband super-absorption can still be realized by properly designing the frequency position of perfect absorption of the cavity-based metasurface. [ABSTRACT FROM AUTHOR]