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The microstructures and mechanical properties of a γ′-strengthened nickel-based superalloy, GH4099, produced by laser powder bed fusion, at room temperature and 900 °C are investigated, followed by three various heat treatments. The as-built (AB) alloy consists of cellular/dendrite substructures within columnar grains aligning in <100> crystal orientation. No γ′ phase is observed in the AB sample due to the relatively low content of Al +Ti. Following the standard solid solution treatment, the molten pool boundaries and cellular/dendrite substructures disappear, whilst the columnar grains remain. The transformation of columnar grains to equiaxed grains occurs through the primary solid solution treatment due to the recovery and recrystallization process. After aging at 850 °C for 480 min, the carbides in the three samples distributed at grain boundaries and within grains and the spherical γ′ phase whose size is about 43 nm ± 16 nm develop in the standard solid solution + aging and primary solid solution + aging samples (SA and PA samples) while the bimodal size of cubic (181 nm ± 85 nm) and spherical (43 nm ± 16 nm) γ′ precipitates is presented in the primary solid solution + secondary solid solution + aging sample (PSA samples). The uniaxial tensile tests are carried out at room temperature (RT) and 900 °C. The AB sample has the best RT ductility (~51% of elongation and ~67% of area reduction). Following the three heat treatments, the samples all acquire excellent RT tensile properties (>750 MPa of yield strengths and >32% of elongations). However, clear ductility dips and intergranular fracture modes occur during the 900 °C tensile tests, which could be related to carbide distribution and a change in the deformation mechanism. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) are a class of noncoding RNAs with a covalently closed loop. Studies have demonstrated that circRNA can function as microRNA (miRNA) sponges or competing endogenous RNAs. Although circRNA has been explored in some species and tissues, the genetic basis of testis development and spermatogenesis in donkeys remain unknown. We performed RNA-seq to detect circRNA expression profiles of adult donkey testes. Length distribution and other characteristics were shown a total of 1971 circRNAs were differentially expressed and 12,648 and 6261 circRNAs were detected from the testis and caput epididymis, respectively. Among these circRNAs, 1472 circRNAs were downregulated and 499 circRNAs were upregulated in the testis. Moreover, KEGG pathway analyses and Gene Ontology were performed for host genes of circRNAs. A total of 39 upregulated circRNA host genes were annotated in spermatogenesis terms, including PIWIL2, CATSPERD, CATSPERB, SPATA6, and SYCP1. Other host genes were annotated in the focal adhesion, Rap1 signaling pathway. Downregulated expressed circRNA host genes participated in the TGF-β signaling pathway, GnRH signaling pathway, estrogen signaling pathway, and calcium signaling pathway. Our discoveries provide a solid foundation for identifying and characterizing critical circRNAs involved in testis development or spermatogenesis. [ABSTRACT FROM AUTHOR]

Lack of archaeological and whole-genome diversity data has restricted current knowledge of the evolutionary history of donkeys. With the advancement of science and technology, the discovery of archaeological evidence, the development of molecular genetics, and the improvement of whole-genome sequencing technology, the in-depth understanding of the origin and domestication of donkeys has been enhanced, however. Given the lack of systematic research, the present study carefully screened and collected multiple academic papers and books, journals, and literature on donkeys over the past 15 years. The origin and domestication of donkeys are reviewed in this paper from the aspects of basic information, cultural origin, bioarcheology, mitochondrial and chromosomal microsatellite sequences, and whole-genome sequence comparison. It also highlights and reviews genome assembly technology, by assembling the genome of an individual organism and comparing it with related sample genomes, which can be used to produce more accurate results through big data statistics, analysis, and computational correlation models. Background: The donkey industry in the world and especially in China is developing rapidly, and donkey farming is transforming gradually from the family farming model to large-scale, intensive, and integrated industrial operations, which could ensure the stability of product quality and quantity. However, theoretical research on donkey breeding and its technical development lags far behind that of other livestock, thereby limiting its industrial development. This review provides holistic information for the donkey industry and researchers, that could promote theoretical research, genomic selection (GS), and reproductive management of the donkey population. [ABSTRACT FROM AUTHOR]

Central Asia (CA) is one of the major sources of global dust aerosols. They pose a serious threat to regional climate change and environmental health and also make a significant contribution to the global dust load. However, there is still a gap in our understanding of dust transport in this region. Therefore, this study utilizes Cloud–Aerosol LiDAR with Orthogonal Polarization (CALIOP) data from 2007 to 2022 to depict the three-dimensional spatiotemporal distribution of dust aerosols over CA and to analyze their transport processes. In addition, the Tropospheric Monitoring Instrument (TROPOMI) was employed to assist in monitoring the movement of typical dust events, and the trajectory model was utilized to simulate the forward and backward trajectories of a dust incident. Additionally, a random forest (RF) model was employed to rank the contributions of various environmental factors. The findings demonstrate that high extinction values (0.6 km−1) are mostly concentrated within the Tarim Basin of Xinjiang, China, maintaining high values up to 2 km in altitude, with a noticeable decrease as the altitude increases. The frequency of dust occurrences is especially pronounced in the spring and summer seasons, with dust frequencies in the Tarim Basin and the Karakum and Kyzylkum deserts exceeding 80%, indicating significant seasonal and regional differences. The high values of dust optical depth (DOD) in CA are primarily concentrated in the summer, concurrent with the presence of a stable aerosol layer of dust in the atmosphere with a thickness of 0.62 km. Furthermore, dust from CA can traverse the Tianshan mountains via the westerlies, transporting it eastward. Additionally, skin temperature can mitigate regional air pollution. Our results contribute to a deeper understanding of the dynamic processes of dust in CA and provide scientific support for the development of regional climate regulation strategies. [ABSTRACT FROM AUTHOR]

Isoxaflutole and atrazine are representative pesticides for weed control in corn fields. Formulations containing these two pesticides have been registered in China, and their residues may threaten food safety and human health. In this study, a method for simultaneous determination of isoxaflutole, atrazine, and their metabolites in fresh corn, corn kernels, and corn straw was established based on modified QuEChERS pre-treatment and high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS). The linearity of seven compounds was good (R2 ≥ 0.9912), and the matrix effect was 48.5–77.1%. At four spiked levels of 0.01, 0.02, 0.05, and 0.5 mg kg−1, all compounds' average recovery was 76% to 116%, with relative standard deviation (RSD) less than 18.9%. Field experiments were conducted in Liaoning, Heilongjiang, Inner Mongolia, Shanxi, Beijing, and Yunnan provinces to study the terminal residues. The terminal residues of all compounds were below the LOQ (0.01 mg kg−1) in fresh corn and corn kernels, and atrazine residues in corn straw ranged from <0.05 mg kg−1 to 0.17 mg kg−1. Finally, a dietary risk assessment was conducted based on residues from field trials, food consumption, and acceptable daily intake (ADI). For all populations, the chronic dietary risk probability (RQc) of atrazine was between 0.0185% and 0.0739%, while that of isoxaflutole was 0.0074–0.0296%, much lower than 100%. The results may provide scientific guidance for using isoxaflutole and atrazine in corn field ecosystems. [ABSTRACT FROM AUTHOR]

Simple Summary: The donkey hindgut is a microbial-rich ecosystem in which caecum and colon fungi play an important role in dietary fiber degradation. In addition, the fibrolytic enzymes produced by hindgut microorganisms are key to the ability of equines to hydrolysis plant fiber. In the present study, the fibrolytic enzyme activities within donkey caecum and colon were firstly measured by spectrophotometry. The dorsal colon presented a higher fibrolytic enzyme activity in comparison with caecum. The fungal community composition along donkey caecum and colon was determined by sequencing an internal transcribed spacer region (ITS) using Illumina MiSeq. The predominant fungi at phylum level were Ascomycota, Basidiomycota, and Neocallimastigomycota. The Aspergillus, Wallemia, Phanerochaete, Fusarium, and Penicillium were detected as the dominant genera, but their metabolic and functional significance in donkey cecum-colon ecosystem need further investigation. In terms of the anaerobic fungi Neocallimastigomycota, its abundance was greater in donkey colon than in caecum. The relative abundance of enzymes related to plant cell wall breakdown were also predicted by PICRUSt, and they were also greater in donkey colon than in caecum. The present study provided new information about fibrolytic enzyme profiles and fungal communities in donkey hindgut. The findings could therefore contribute to the further understanding of the fungal taxa and their dietary fiber degradation mechanisms in donkey hindgut ecosystem. The fibrolytic enzymes and the hindgut fungi in donkey cecum-colon ecosystem play an important role in dietary fiber digestion. A better understanding of the fibrolytic enzyme profiles and the fungal community along donkey caecum and colon is key for optimizing hindgut function. In the present study, the fibrolytic enzyme activities within donkey caecum and colon were firstly measured by spectrophotometry. Activities of carboxymethyl cellulase, avicelase, xylanase, and acetyl esterase were greater in donkey dorsal colon than in caecum, indicating that the colon microorganisms may be more efficient in producing fibrolytic enzymes compared to caecum microbes. The fungal community composition along donkey hindgut was determined by sequencing ITS region using Illumina MiSeq. Three fungal phyla were identified by sequence comparison: Ascomycota (66.8%–74.4%), Basidiomycota (21.6%–30.9%), and Neocallimastigomycota (0.9%–3.3%). The Aspergillus, Wallemia, Phanerochaete, Fusarium, and Penicillium were detected as the dominant genera, but their metabolic and functional significance in donkey cecum-colon ecosystem need further investigation. In terms of the anaerobic fungi Neocallimastigomycota, its abundance was greater in donkey colon than in caecum (p < 0.05), indicating that the donkey hindgut region was associated with differences in fungal community composition. Moreover, the relative abundance of enzymes related to plant cell wall degradation were predicted by PICRUSt, and they were also lower in caecum than in colon. The present study provided new information about fibrolytic enzyme profiles and fungal composition in donkey hindgut ecosystem. [ABSTRACT FROM AUTHOR]

Layered δ-MnO2 catalysts were prepared using the one-step redox method in precursor solutions with five different pH values (pH = 7, 9, 11, 13, and 14). The effects of pH on the physical properties and catalytic activity of the catalyst were investigated through XRD, SEM, TEM, BET, XPS, H2-TPR, and HCHO degradation tests at room temperature. The results showed that the layer spacing, manganese vacancy content, Mn4+/Mn3+ ratio, and surface-reactive oxygen species content of MnO2 increased with the increase in pH value in the alkaline range. When the catalyst was prepared at pH = 13, the above characteristics of the catalyst reached the optimal value which contributed to the high catalytic activity. Combined with the related characterization results, it was proved that changing the pH can affect the degree of oxidation in the catalyst synthesis process, increase the number of active oxygen and the oxygen mobility of the catalyst, and effectively improve the catalytic activity of the manganese dioxide catalyst for HCHO. This work represents a giant step toward the preparation of an effective catalyst for practical applications of HCHO removal at room temperature at a low concentration and high velocity. [ABSTRACT FROM AUTHOR]

Water–gas displacement occurring during the drainage of water-soaked goafs facilitates the oxidation of water-soaked coal. The characteristics of oxygen migration and the oxidation and spontaneous combustion (SC) of soaked residual coal during goaf drainage were explored through laboratory research, water drainage simulation and on-site measurement. The results reveal that compared with raw coal samples, the amount and rate of gas products of water-soaked coal samples are higher in the heating oxidation process, demonstrating a strengthened spontaneous combustion (SC) propensity. Its cross-point temperature falls and the apparent activation energy decreases by 1.43–8.75%, that is, the soaked coal sample is easier to spontaneously combust during the drainage of water-soaked goafs. Through simulation, it is found that after water is drained, air leakage in the goaf is significantly intensified, and the pressure difference inside and outside the goaf reaches 498 Pa. By taking the air inlet roadway as the air leakage point for fitting, it is found that the oxygen concentration in the air leakage range increases to 18% during water drainage. The simulation results are basically consistent with the on-site measurement. The on-site monitoring result shows that during water drainage of 7225 goaf in Qinan Coal Mine, water-immersed coal is more prone to spontaneous combustion, and air leakage leads to low-temperature oxidation of water-immersed coal, which increases the on-site temperature rapidly and increases the risk of spontaneous combustion in the goaf. With respect to water drainage in the goaf, an optimization measure of fixed-point and quantitative nitrogen injection during water drainage was put forward on site. [ABSTRACT FROM AUTHOR]

The uncertainties in soil erosion (SE) are further intensified by various factors, such as global warming, regional warming and humidification, and vegetation cover changes. Moreover, quantitative evaluations of SE in major basins of Central Asia (CA) under changing environments have rarely been conducted. This study conducted quantitative evaluation of SE in four major basins (Syr Darya Basin (SDB), Amu Darya Basin (ADB), Ili River Basin (IRB) and Tarim River Basin (TRB) using the Revised Universal Soil Loss Equation (RUSLE) and analyzed the main driving factors. SE quantities in the basins presented relatively consistent upward fluctuating trends from 1982 to 2017. Vegetation cover variation fluctuated significantly from 1982 to 2017. Specifically, vegetation cover decreased continuously in SDB, ADB, and IRB, but increased gradually in TRB. Pixels with positive spatial variation of vegetation mainly occurred around lakes and oases near rivers. The Normalized Difference Vegetation Index (NDVI) showed higher correlation with precipitation (80.5%) than with temperature (48.3%). During the study period, the area of arable land (AL) exhibited the largest change among all land use types in CA. Under long-term human activities, the proportion of NDVI of other land types converting to AL was the highest. In the structural equation model (SEM), precipitation, temperature, Shannon Diversity Index (SHDI), and NDVI strongly influenced SE. Overall, the major basins in CA were jointly affected by climate, human activities, and vegetation. Specifically, climatic factors exerted the strongest influence, followed by SHDI (human activities). SE was found to be relatively serious in ADB, SDB, and IRB, with SE in SDB even approaching that in the Loess Plateau. Under the background of global changes, appropriate water and land resource management and optimization configurations should be implemented in CA with reference to TRB in order to relieve local SE problems. [ABSTRACT FROM AUTHOR]

Simple Summary: Weaning is a stressful event as it is an abrupt separation of donkey foals from their mothers. Donkeys experience a variety of changes and stresses, such as physiological, environmental and diet challenges. The oral cavity is the gateway to total body wellness, and the oral microbiome is important in maintaining oral as well as systemic health. However, little is known on the effect of weaning on the oral microbiome of donkeys. Therefore, the present study was conducted to investigate the relationship between weaning and oral microbial changes using 16S rRNA gene sequencing. The results showed that significant changes in the oral microbiome occurred during the weaning transition period. In addition, the functions related to carbohydrate metabolic pathways were obviously enriched in the oral microbiome in postweaning donkeys compared with preweaning donkeys. The current study provides a deeper insight into the oral microbiota changes during the weaning period and helps to increase awareness of feed changes in donkey foals. As the initiation point of digestion, the oral microbiome is important in maintaining oral and systemic health. However, the composition of oral microbial communities and the influence of weaning on the oral microbiota of donkey foals remains poorly characterized. The present study used buccal swab samples to determine the changes in oral microbial communities occurring at the time of weaning. A total of 20 oral swab samples were collected from two groups: preweaning donkey foals (PreW group, n = 10) and postweaning donkey foals (PostW group, n = 10). The donkey oral microbiome was analyzed by 16S rRNA gene sequencing using Illumina MiSeq. This study is the first report of the donkey oral microbiome in association with weaning. Compared to the preweaning donkeys, the oral bacteria diversity in the postweaning donkeys was increased, with a higher Simpson index. Changes in the composition of the oral microbiota between the PreW and PostW groups were observed in the present study. At the phylum level, the relative abundance of Firmicutes and Myxococcota was significantly greater in the PostW than in the PreW group. At the genus level, the Gemella, unclassified_o__Lactobacillales, and Lactobacillus were increased in the postweaning donkeys. The donkeys' oral microbial functions were predicted using PICRUSt, and the functions related to carbohydrate metabolic pathways were significantly enriched in the oral microbiome in the PostW donkeys. In summary, the current study provides a deeper insight into the oral microbiota changes during the weaning period, and the influence of weaning together with the documented changes in diversity and composition will help us to obtain a better understanding of their long-term health impact within the oral cavities of donkey foals. However, a major limitation of the present study was that the samples were obtained from different animals in the PreW and PostW groups, which may have resulted in variability among the different individuals. Further investigation is needed to monitor the shift in oral microbes in the same individuals during the weaning period. [ABSTRACT FROM AUTHOR]

In order to improve the impact resistance of sandwich panels under low-velocity impact, the lotus leaf vein is selected as a biological prototype to design a bio-inspired honeycomb (BIH) sandwich panel. ABAQUS is used to establish and effectively verify the finite element (FE) model of the BIH sandwich panel. To systematically compare and study the mechanical properties of BIH and conventional hexagonal honeycomb sandwich panels under low-velocity impact, the maximum displacement of face-sheets, the deformation mode, the plastic energy consumption and the dynamic response curve of the impact end are presented. At the same time, the performance differences between them are revealed from the perspective of an energy absorption mechanism. Furthermore, the influence of the circumscribed circle diameter ratio of the BIH trunk to branch (γ), the thickness ratio of the trunk to branch (K) and the impact angle (θ) on impact resistance is studied. Finally, the BIH sandwich panel is further optimized by using the response surface method. It can be concluded that, compared to conventional hexagonal honeycomb sandwich panels, the addition of walls in the BIH sandwich panel reduces the maximum deformation of the rear face-sheet by 10.29% and increases plastic energy consumption by 8.02%. Properly adjusting the structural parameters can effectively enhance the impact resistance of the BIH sandwich panel. [ABSTRACT FROM AUTHOR]

Electroencephalography (EEG) is widely used for monitoring the depth of anesthesia in surgical patients. Distinguishing age-related EEG features under general anesthesia will help to optimize anesthetic depth monitoring during surgery for elderly patients. This retrospective cohort study included 41 patients aged from 18 to 79 years undergoing noncardiac surgery under general anesthesia. We compared the power spectral signatures and phase–amplitude coupling patterns of the young and elderly groups under baseline and surgical anesthetic depth. General anesthesia by sevoflurane significantly increased the spectral power of delta, theta, alpha, and beta bands and strengthened the cross-frequency coupling both in young and elderly patients. However, the variation in EEG power spectral density and the modulation of alpha amplitudes on delta phases was relatively weaker in elderly patients. In conclusion, the EEG under general anesthesia using sevoflurane exhibited similar dynamic features between young and elderly patients, and the weakened alteration of spectral power and cross-frequency coupling patterns could be utilized to precisely quantify the depth of anesthesia in elderly patients. [ABSTRACT FROM AUTHOR]

Ecosystem services (ESs) are important for supporting human development. However, a changing climate and anthropogenic impacts are resulting in the degradation of dryland ecosystems to varying degrees. While there has been the global implementation of Ecological Restoration Programs (ERPs) to restore degraded ecosystems, there remains limited comprehensive assessment of their impacts on ESs of drylands. In this study, the sandy areas of northern China were used as the study area. The RUSLE, RWEQ, CASA, and InVEST models were used to simulate four major ESs: soil conservation (SC), sand fixation (SF), carbon sequestration (CS), and water yield (WY). The study aimed to evaluate the influences of various ERPs on major ESs. The dominant factors affecting the overall benefits provided by ESs were also identified. Since ERPs were implemented, forest areas have increased by 2.8 × 104 km2, whereas the areas of cropland, shrubland, and grassland have decreased. There were generally increasing trends in SF, SC, and CS, whereas there was a decreasing trend in WY. We then used a scenario-based simulation approach to eliminate the influence of climate variability on ESs. The results showed increasing trends in SF, SC, and CS, whereas there were minimal changes in WY. The results suggested that although ERPs can significantly increase regional ESs, unregulated expansion in vegetation can result in a water crisis and affect regional water security. [ABSTRACT FROM AUTHOR]

The radar constant calibration in incoherent scatter radar ion line processing is essential for the data quality and was not paid enough attention in previous studies. In this investigation, based on several experiments made by the newly built Sanya incoherent scatter radar (SYISR), we made and evaluated the ion line calibration by plasma line both in case study and statistically. The calibration factor had local time and altitude variations, due to the corresponding variations of the transmitted power, the radar gain, and the noise temperature. We obtained a mean calibration factor of 1.35 by the simultaneous measured plasma line and ion line electron density and applied it to a one-month ion line observation calibration. Through a co-located ionosonde measured foF2 evaluation, the calibration decreased the mean deviation from −1.92 MHz (−18%) to −0.33 MHz (−3%), which resulted in much better agreement between the ion line foF2 after calibration and the ionosonde results. The existed deviations between after calibration and ionosonde results were due to the uncertainties either in the used calibration factor or the ionosonde measurements. An empirical Te/Ti usage in raw electron density estimation and ignoring the seasonal and short-term variations of the effecting factors might influence the calibration performance. Using the to-be-completed SYISR Tristatic System, the performance of plasma line calibration technique is expected to be improved in the future. [ABSTRACT FROM AUTHOR]

Space objects around the Earth are a potential pollution source for ground-based radio observations. The Sanya incoherent scatter radar (SYISR) is a newly built active digital phased array, all solid-state transmitting and digital receiving incoherent scatter radar in Sanya (18.3°N, 109.6°E), with the main purpose of ionospheric monitoring and investigations. In this study, we presented the effect of the greatly increased number of space objects on ionospheric observations through SYISR. Firstly, we showed the space object pollution on the range-time-intensity (RTI), autocorrelation function (ACF)/power spectra, and ionosphere parameter of SYISR measurements. An altitude of around 600 km is the region where space objects occur most frequently. Then, we eliminated the space object pollution using the traditional smallest of constant-false-alarm-rate (SO-CFAR) algorithm. However, pollution from smaller space objects remains, whose reflected echo is comparable to or lower than the background ionosphere, which results in unrealistic retrieved ionospheric electron density. Furthermore, we quantitatively assessed the space object effect based on the current space object orbit database and simulation. The pollution should linearly increase with the increase in the number of space objects in the future. Among the space objects, whose radar cross section (RCS) and orbit information are now published, there still exist ~9000 (~37% of the total number) space objects, whose effect is difficult to eliminate. This study is beneficial to the data process of SYISR and has implications for similar types of ionospheric observations by radar. [ABSTRACT FROM AUTHOR]

Sanya incoherent scatter radar (SYISR) is a newly developed phased array incoherent scatter radar in the low latitudes of China located at Sanya (18.3°N, 109.6°E), Hainan Province. The main objective of SYISR is to observe the ionosphere. Given its frequency and power, it should have the capability to observe the troposphere. In this study, we show several tropospheric wind experiments that may indicate radar function expansion and capability verification, although observing the troposphere will not be an operation mode in the future. Reliable radar echoes were detected by SYISR up to 20 km with a turbulence scale of 0.35 m and a frequency of 430 MHz. Generally, both the geometric (GEO) method and the velocity azimuth display (VAD) method give similar wind profiles. Above 10 km, the discrepancy between the two methods becomes nonnegligible. For the same method, the discrepancy above 15–20 km among winds derived from different zenith angle measurements is nonnegligible. The VAD methods give more reasonable results at higher altitudes. The standard deviation of the difference (SYISR radar minus the reanalysis data ERA5) for zonal wind and meridional wind was 1.1 m/s and 0.78 m/s, respectively. During rainfall, we can distinguish the spectrum of rainfall and atmospheric turbulence from the power spectrum according to the spectral widths and Doppler frequency shifts. [ABSTRACT FROM AUTHOR]

The high-value utilization of sulfate-rich tailings (SRCTs) can accelerate their mass consumption, so the many problems caused by the massive accumulation of SRCTs can be alleviated, such as environmental pollution, land occupation, security risk, etc. This study proposes using SRCTs to replace fine natural aggregates in MgO-activated slag materials (MASMs) and investigate the influence of the sulfur content in SRCTs on the properties of MASMs. The experimental results showed that the 28 d compressive strength of MASM mortars was increased by up to 83% using SRCT composites. Two major mechanisms were discovered: additional hydration product formation and pore structure refinement. The results of XRD suggested that incorporating SRCT composite into MASMs increased the production of expansive sulfate-containing hydration products, such as ettringite, gypsum, and hydroxyl-Afm. The results of element mapping showed that the oxidation of pyrite in SRCTs could release sulfates into the surrounding area and participate in the hydration of MASM, indicating that SRCTs can work as an auxiliary activator for MASMs. Furthermore, the addition of SRCT significantly refined the pore structure of MASMs, leading to the reduction in porosity by up to 37.77%. These findings confirm a synergistic effect on activating the slag between SRCTs and MgO, promoting the mass utilization of SRCTs. As a result, the additional expansive hydration products contribute to the enhanced compressive strength and refined pore structure. [ABSTRACT FROM AUTHOR]

Simple Summary: The bacteria residing in donkey hindgut are clearly divided into two distinct ecological sites: liquid phase (Lq) and adherent fraction (Ad). Though both the Lq and Ad bacteria play an important role in feed digestion, the Ad bacteria have not previously been specifically sampled or directly compared with the Lq bacteria. The present study was conducted to comparatively analyze the bacterial community composition between the Lq and Ad fraction within the donkey caeco-colic ecosystem. The results showed that the relative abundance of Bacteroidota, Spirochaetota, Fibrobacterota and Patescibacteria in the Ad fraction was greater than the Lq fraction, indicating that bacteria associated with plant biomass are mainly responsible for plant fiber degradation. Regarding the genus level, the liquid phase presented higher abundance in Lactobacillus compared to Ad fraction. The activities of enzymes related to fiber degradation were predicted by PICRUSt, and they were also higher in Ad bacteria than Lq. In addition, the bacterial community composition was also distinct within the donkey caecum, ventral colon and dorsal colon. The present study provides evidence that bacteria adherent to feed particles may be better at plant fiber degradation than Lq bacteria due to the greater cellulolytic populations and activities. Donkey hindgut is an enlarged fermentative chamber that harbors a highly complex and extremely abundant community of anaerobic bacteria. It can be divided into two different ecological sites: liquid (Lq) phase and adherent fraction (Ad) colonized by bacteria. However, the Ad bacteria have not previously been specifically collected or directly compared with the Lq bacteria. In the present study, the digesta collected from the caecum, ventral colon and dorsal colon of nine Dezhou donkeys was separated into Lq and Ad fractions. The bacterial community structure was comparatively determined using 16S rRNA gene sequences by Illumina MiSeq. The Ad bacteria had a higher bacterial diversity than Lq bacteria due to the higher Chao and ACE index (p < 0.05). The predominant bacteria at the phylum level were Firmicutes (55.4~74.3%) and Bacteroidota (13.7~32.2%) for both the Lq and Ad fraction. The relative abundance of Bacteroidota, Spirochaetota, Fibrobacterota and Patescibacteria in the Ad fraction was greater than Lq (p < 0.05), suggesting that bacteria associated with feed particles were mainly responsible for plant fiber degradation. At the genus level, the abundance of Lactobacillus in Lq was greater than that in the Ad fraction (p < 0.05), indicating that the bacteria in the Lq fraction were better at hydrolyzing readily fermentable carbohydrates. PICRUSt showed that the activities of enzymes related to fiber degradation in the Ad fraction were also greater than Lq. In addition, the hindgut region also had a significant effect on the bacterial community composition. The relative abundance of Rikenellaceae_RC9_gut_group, Clostridium_sensu_stricto_1, Christensenellaceae_R-7_group and norank_Bacteroidales_BS11_gut_group was increased (p < 0.05) along the donkey hindgut. In summary, the present study provides evidence that bacteria adherent to plant biomass were different to those in the liquid phase within the donkey caeco-colic digesta, and bacteria associated with feed particles may mainly be responsible for plant fiber degradation. [ABSTRACT FROM AUTHOR]

Previous ground-based, radar lunar imaging experiments have usually employed the Range-Doppler (RD) algorithm. This algorithm performs in the frequency domain and has high computational efficiency. However, in the case of a long coherent integration time, the defocus phenomenon will appear, and the image will be smeared. This study proposes the use of the back projection (BP) algorithm to obtain focused lunar images to solve this problem. The BP algorithm is a time-domain algorithm which is frequently employed in synthetic aperture radar (SAR) imaging and can theoretically achieve the focused imaging of each pixel in an arbitrarily long coherent integration time. However, the largest drawback of this algorithm is its high computational complexity. Therefore, this study only applies this method to map local regions of the moon. We select Sanya incoherent scatter radar (SYISR) as the transmitting and receiving device and utilize the linear frequency modulation chirp pulse to transmit right-hand, circularly polarized electromagnetic waves and to receive left-hand, circularly polarized echoes. RD and BP algorithms are simultaneously adopted to image the Pythagoras crater region, and a contrastive analysis is performed. The results show that the BP algorithm can be well applied to a ground-based, radar lunar imaging experiment and that it has a better focusing performance, but the effect is not as obvious as expected. Thus, the processing method needs to be further improved. In addition, the computational efficiency of BP is very low, and certain fast algorithms need to be applied to improve it. [ABSTRACT FROM AUTHOR]

A highly selective and sensitive method for Cd(II) detection was developed based on aptamer and gold nanoparticles (AuNPs) combined with a colorimetric smartphone readout. The experimental conditions such as reaction time of polydiene dimethyl ammonium chloride (PDDA) and AuNPs, PDDA dose, time of aptamer and PDDA incubation, and aptamer concentration were optimized. Under the optimized conditions, the color and red(R) value of the solution was concentration-dependent on Cd(II). The proposed method exhibited a linear range of 1–400 ng/mL (r2 = 0.9794) with a limit of detection (LOD) of 1 ng/mL. This method had been successfully applied to test and quantify Cd(II) in water and rice samples, and the results were in full agreement with those from the atomic absorption spectrometer. Therefore, low-cost colorimetry demonstrated its potential for practical application in visual or quantitative detection with a smartphone. This approach can be readily applied to other analytes. [ABSTRACT FROM AUTHOR]

As an attractive drug-target, retinoic acid receptor-related orphan receptor-gamma-t (RORγt) has been employed widely to develop clinically relevant small molecular modulators as potent therapy for autoimmune disease and cancer, but its molecular mechanism of action (MOA) remains unclear. In the present study, we designed and discovered two novel RORγt ligands that are similar in structure, but different in efficacy. Using fluorescence resonance energy transfer (FRET) assay, compound 1 was identified as an agonist with an EC50 of 3.7 μM (max. act.: 78%), while compound 2 as an inverse agonist with an IC50 value of 2.0 μM (max. inh.: 61%). We performed molecular dynamics (MD) simulations, and elucidated the MOA of RORγt agonist and inverse agonist. Through the analyses of our MD results, we found that, after RORγt is bound with the agonist 1, the side chain of Trp317 stays in the gauche- conformation, and thus helps to form the hydrogen bond, His479-Trp502, and a large hydrophobic network among H11, H11′, and H12. All these interactions stabilize the H12, and helps the receptor recruit the coactivator. When the RORγt is bound with the inverse agonist 2, the side chain of Trp317 is forced to adopt the trans conformation, and these presumed interactions are partially destroyed. Taken together, the critical role of residue Trp317 could be viewed as the driving force for the activation of RORγt. [ABSTRACT FROM AUTHOR]