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The Pamir‒Tian Shan collision zone, located at the northwestern edge of the Himalaya‒Qingzang orogenic belt, provides a natural laboratory for investigating the development of fluvial terraces controlled by regional climate change and tectonic uplift. In this study, we conducted geomorphological mapping and terrestrial cosmogenic nuclide 10Be dating of fluvial terraces in the Wuheshalu syncline, within the Pamir‒Tian Shan collision zone. Four major fluvial terraces were identified in the Wuheshalu syncline, with ages of approximately 187, 141, 90, and 19 ka, respectively. These terraces were abandoned during three glacial‒interglacial transition periods (Marine Isotope Stage 6/5 (MIS6/5), cold-to-warm transition period of MIS5, and end of MIS2 or MIS2/1) and one interglacial‒glacial period (MIS7/6), and exhibit a strong correlation with regional climate change. Tectonic uplift contributed only one-third of the observed fluvial incision. These results suggest that river incision and terrace formation in the Pamir‒Tian Shan collision zone are primarily driven by periodic fluctuations in climate, with a lesser contribution from tectonic uplift.

Lactate dehydrogenase (LDH), a nonspecific inflammatory biomarker, has been used in the assessment of acute myocardial infarction, acute hepatitis, acute lung injury, and other severe diseases. However, no studies have evaluated the prognostic value of LDH in patients with non-traumatic intracerebral hemorrhage (ICH). This cohort study aims to assess the association between LDH levels and 28-day all-cause mortality in patients with non-traumatic ICH. Data for this retrospective cohort analysis were obtained from the MIMIC-IV (v2.2) database, and the study included patients with non-traumatic ICH as defined by the International Classification of Diseases, 9th and 10th editions. Patients were categorized into four distinct groups based on their LDH levels. The primary outcome of interest was the 28-day mortality rate. To analyze these associations and assess the consistency of interactions, subgroup analyses, Cox regression analysis, Kaplan-Meier (KM) curves, and nonlinear analysis were conducted. A total of 406 patients with non-traumatic ICH were enrolled in the study and were divided into quartiles based on LDH levels. The KM curve indicated that the 28-day all-cause mortality rate of patients in the Q4 group (LDH > 287.25) was significantly higher than in the Q1 (LDH < 194.7) (P < 0.001) and Q2 (194.7 < LDH < 233.0) (P < 0.001) groups, though not significantly different from Q3 (P = 0.140). Multivariate Cox proportional hazards analysis revealed that patients in the highest LDH quartile had a significantly increased risk of mortality compared to those in the lowest quartile across three models: unadjusted [HR, 3.401; 95% CI, 1.719–6.731; P < 0.001], partially adjusted [HR, 2.422; 95% CI, 1.211–4.846; P = 0.012], and fully adjusted [HR, 3.054; 95% CI, 1.522–6.126; P = 0.002]. Restricted cubic spline (RCS) models revealed an L-shaped association between LDH levels and the 28-day all-cause mortality rate, indicating a non-linear relationship (P < 0.001). No significant interactions were observed between LDH levels and other factors in the subgroup analyses (all P for interaction > 0.05). Our findings indicate a significant association between 28-day all-cause mortality and LDH levels in patients with non-traumatic intracerebral hemorrhage. Specifically, patients with elevated LDH levels within the first 24 hours of ICU admission are at a higher risk of mortality.

Oxidative stress-induced neuronal damage is the main cause of neurodegenerative diseases, which is characterized by cognitive impairment. We selected a high-content natural alkaloid, trigonelline, from daily vegetables eggplants. The results showed that eggplants were rich in trigonelline. It has antioxidant and anticancer effects, but there is limited research on neurodegenerative diseases. An in vitro neuronal injury model was established using PC12 cells damaged by H2O2 to explore neuroprotective effect of trigonelline. An aging model was established in vivo by injecting D-galactose into mice for 6 weeks. Trigonelline have been found to improve cognitive impairment by improving brain-damage, enhancing antioxidant system activity in mice, regulating the activity of ChAT and AChE to maintain the balance of cholinergic system. The experimental results indicate that trigonelline has good neuroprotective effects, providing a reference for the development of functional foods made from eggplant and trigonelline, as well as prevention and treatment of neurodegenerative diseases.

A self-calibration method utilizing spherical constraints is proposed for calibration of robot end-effectors. The method establishes a mathematical model to account for both the geometric errors of the robot and the deformation errors of the end-effector. A nonlinear least-squares parameter identification technique based on spherical constraints is employed to achieve autonomous calibration of the end-effector. Contrasted with methodologies relying on point plane or distance constraints, this novel technique delivers superior positioning accuracy, streamlined operational procedures and enhanced efficiency. Both simulation and experimental validation confirm that the self-calibration method using spherical constraints improves the positioning accuracy of the robot end-effector from 3 mm to 0.3 mm, showing the effectiveness of the method.

Abstract Introduction Recent observational studies have reported the association between ischemic stroke (IS) and cerebral microbleeds (CMBs). Whether this reflects a causal association remains to be established. Herein, we adopted a two-sample bidirectional Mendelian randomization (MR) analysis to comprehensively evaluate the causal association of IS and CMBs. Methods The summary-level genome-wide association studies (GWASs) data of IS were obtained from the GIGASTROKE consortium (62,100 European ancestry cases and 1,234,808 European ancestry controls). All IS cases could be further divided into large-vessel atherosclerosis stroke (LVS, n = 6399), cardio-embolic stroke (CES, n = 10,804) and small-vessel occlusion stroke (SVS, n = 6811). Meanwhile, we used publicly available summary statistics from published GWASs of CMBs (3556 of the 25,862 European participants across 2 large initiatives). A bidirectional MR analysis was conducted using inverse-variance weighting (IVW) as the major outcome, whereas MR-Egger and weighted median (WM) were used to complement the IVW estimates as they can provide more robust estimates in a broader set of scenarios but are less efficient (wider CIs). A Bonferroni-corrected threshold of p

Colorectal cancer (CRC) accounts for the third highest morbidity burden among malignant tumors worldwide. Previous studies investigated gut microbiome changes that occur during colorectal adenomas (CRA) progression to overt CRC, thus highlighting the importance of the gut microbiome in carcinogenesis. However, few studies have examined gut microbiome characteristics across the entire spectrum, from CRC development to treatment. The study used 16S ribosomal ribonucleic acid and internal transcribed spacer amplicon sequencing to compare the composition of gut bacteria and fungi in a Chinese cohort of healthy controls (HC), CRC patients, CRA patients, and CRC postoperative patients (PP). Our analysis showed that beta diversity was significantly different among the four groups based on the gut bacterial and fungal data. A total of 51 species of bacteria and 8 species of fungi were identified in the HC, CRA, CRC, and PP groups. Correlation networks for both the gut bacteria and fungi in HC vs. CRA, HC vs. CRC, and HC vs. PP indicated some hub bacterial and fungal genera in each model, and the correlation between bacterial and fungal data indicated that a highly significant negative correlation exists among groups. Quantitative polymerase chain reaction (qPCR) analysis in a large cohort of HC, CRC, CRA, and PP patients demonstrated a significantly increasing trend of Fusobacterium nucleatum, Bifidobacterium bifidum, Candida albicans, and Saccharomyces cerevisiae in the feces of CRC patients than that of HC patients (p < 0.01). However, the abundance levels of CRA and PP were significantly lower in HC patients than those in CRC patients. Further studies are required to identify the functional consequences of the altered bacterial/fungal composition on metabolism and CRC tumorigenesis in the host.

Shear stirrups in a prestressed ultra-high performance concrete (UHPC) beam might be eliminated due to the high tensile strength of UHPC. This research aims to investigate shear behavior of the externally prestressed UHPC beams without stirrups. Thirteen UHPC beams were tested with the experimental parameters of prestressing level, shear span-to-depth ratio, longitudinal reinforcement ratio, fiber content, and stirrup ratio. The results showed that the beam with the longitudinal reinforcement ratio of 2.0 % under a shear span-to-depth ratio of 2.0 failed in flexure, even though additionally applying a higher prestressing up to 40 % of tensile strength of prestressing tendon. However, the externally prestressed UHPC beams under a shear span-to-depth ratio lower than 2.0 failed in shear. The shear strength of UHPC beam increased with a higher prestressing, lower shear span-to-depth ratio, more longitudinal reinforcements and stirrups, and higher fiber content. French Standard formula and PCI formula for shear design were conservative, irrespective of the existence or absence of stirrups in the prestressed UHPC beam. The calculated results indicated that the externally prestressed UHPC beams met the requirement of shear design codes when no stirrup was employed.

The 2022 Luding Ms 6.8 earthquake has drawn attention to the Xianshuihe fault zone. Historically, there was an M 73/4 earthquake in this region in 1786. Because the surface rupture of this historic earthquake was not obvious, there is still much debate over the extent of the surface rupture, which is critical for comprehending tectonic activity and assessing seismic risk for the Xianshuihe fault (XSHF). In particular, the seismogenic structure of this earthquake was connected by three active left-lateral strike-slip faults—the Anninghe fault (ANHF), Daliangshan fault (DLSF), and XSHF—where a large earthquake could cause multi-fault rupture. Given these criteria, we report the results of a series of trenches excavated in the vicinity of the epicenter at the northern section of the DLSF, the northern section of the ANHF, the Zheduotang section, and the Selaha section of the XSHF. We find that 1) three palaeoseismic events have been revealed on the northern section of the ANHF: BE1, ∼1003 AD; BE2, 1000–1182 AD; and BE3, 1536 AD as M 7 earthquakes, and 2) two palaeoseismic events have occurred on the Selaha fault during the last 500 years. The first event corresponds to the AD 1725 Kangding M 7 earthquake, and the latest event may be the AD 1786 M 73/4 earthquake. 3) Three palaeoseismic events occurred on Zheduotang: ZD1, 1215 BC∼315 AD; ZD2, 830 BC∼705 AD; and ZD3, the 1955 AD Kangding M 71/2 earthquake. 4) The 1786 Kangding M 73/4 earthquake was probably a multi-fault rupture event, as evidenced by the trenching profile evidence, nearby offset geomorphic features, and historical earthquake data. Not only the Moxi fault, a seismogenic structure, but also the southern end of the Selaha fault to the north and the Shimian fault (DLSF) to the south simultaneously broke during this earthquake.

Salinity is an important environmental factor influencing crop growth and yield. Malate dehydrogenase (MDH) catalyses the reversible conversion of oxaloacetate (OAA) to malate. While many MDHs have been identified in various plants, the biochemical function of MDH in rice remains uncharacterised, and its role in growth and salt stress response is largely unexplored. In this study, the biochemical function of OsMDH12 was determined, revealing its involvement in regulating tiller number and salt tolerance in rice. OsMDH12 localises in the peroxisome and is expressed across various organs. In vitro analysis confirmed that OsMDH12 converts OAA to malate. Seedlings of OsMDH12-overexpressing (OE) plants had shorter shoot lengths and lower fresh weights than wild-type (WT) plants, while osmdh12 mutants displayed the opposite. At maturity, OsMDH12-OE plants had fewer tillers than WT, whereas osmdh12 mutants had more, suggesting OsMDH12’s role in tiller number regulation. Moreover, OsMDH12-OE plants were sensitive to salt stress, but osmdh12 mutants showed enhanced salt tolerance. The Na+/K+ content ratio increased in OsMDH12-OE plants and decreased in osmdh12 mutants, suggesting that OsMDH12 might negatively affect salt tolerance through influencing the Na+/K+ balance. These findings hint at OsMDH12’s potential as a genetic tool to enhance rice growth and salt tolerance.

Microbiome and their metabolites are increasingly being recognized for their role in colorectal cancer (CRC) carcinogenesis. Towards revealing new CRC biomarkers, we compared 16S rRNA gene sequencing and liquid chromatography-mass spectrometry (LC–MS) metabolite analyses in 10 CRC (TCRC) and normal paired tissues (THC) along with 10 matched fecal samples (FCRC) and 10 healthy controls (FHC). The highest microbial phyla abundance from THC and TCRC were Firmicutes, while the dominant phyla from FHC and FCRC were Bacteroidetes, with 72 different microbial genera identified among four groups. No changes in Chao1 indices were detected between tissues or between fecal samples whereas non-metric multidimensional scaling (NMDS) analysis showed distinctive clusters among fecal samples but not tissues. LEfSe analyses indicated Caulobacterales and Brevundimonas were higher in THC than in TCRC, while Burkholderialese, Sutterellaceaed, Tannerellaceaea, and Bacteroidaceae were higher in FHC than in FCRC. Microbial association networks indicated some genera had substantially different correlations. Tissue and fecal analyses indicated lipids and lipid-like molecules were the most abundant metabolites detected in fecal samples. Moreover, partial least squares discriminant analysis (PLS-DA) based on metabolic profiles showed distinct clusters for CRC and normal samples with a total of 102 differential metabolites between THC and TCRC groups and 700 metabolites different between FHC and FCRC groups. However, only Myristic acid was detected amongst all four groups. Highly significant positive correlations were recorded between genus-level microbiome and metabolomics data in tissue and feces. And several metabolites were associated with paired microbes, suggesting a strong microbiota-metabolome coupling, indicating also that part of the CRC metabolomic signature was attributable to microbes. Suggesting utility as potential biomarkers, most such microbiome and metabolites showed directionally consistent changes in CRC patients. Nevertheless, further studies are needed to increase sample sizes towards verifying these findings.

Migratory birds are the primary source and reservoir of antibiotic-resistant genes (ARGs) related to their gut microbes. In this study, we performed metagenomics analysis to study the gut microbial communities and ARGs of Anser erythropus wintering at Shengjin (SJ) and Caizi (CZ) Lakes. The results showed that bacteria, fungi, viruses, and archaea were the dominant gut microbes. Principal component analysis (PCA) indicated that the microbiota compositions significantly differed between the two populations. Diet may be the most crucial driver of the gut microbial communities for A. erythropus. This species fed exclusively on Poaceae spp. at Shengjin Lake and primarily on Carex spp. at Caizi Lake. Tetracycline, macrolide, fluoroquinolone, phenicol, and peptide antibiotics were the dominant resistant types. ARGs had a significantly higher abundance of operational taxonomic units (OTUs) in the Shengjin Lake samples than in Caizi Lake samples. PCA indicated that most Shengjin Lake samples significantly differed in gut microbiota composition from those obtained at Caizi Lake. This difference in gut microbiota composition between the two lakes' samples is attributed to more extensive aquaculture operations and poultry farms surrounding Shengjin Lake than Caizi Lake. ARGs–microbes associations indicated that 24 bacterial species, commonly used as indicators of antibiotic resistance in surveillance efforts, were abundant in wintering A. erythropus. The results revealed the composition and structural characteristics of the gut microbiota and ARGs of A. erythropus, pointing to their high sensitivities to diet habits at both lakes. This study also provides primary data for risk prevention and control of potential harmful pathogens that could endanger public health and therefore are of major significance to epidemiological and public health.

Vaginal and cervical canal bacteria are associated with women’s health and pregnancy outcomes. Here, we compared their composition and characteristics in 37 reproductive-aged Chinese women including 24 pregnant women with cervical incompetence (vaginal and cervical canal bacteria formed Groups A and B, respectively) and 13 healthy pregnant women (vaginal and cervical canal bacteria formed Groups C and D, respectively) using high-throughput sequencing of the V4 region of 16S rRNA gene. The results of alpha and beta diversity analysis, respectively, indicated no statistical differences between Groups A and B (p = 0.32, 0.06), nor Groups B and D (p = 0.69, 0.74); however, differences were found between Groups C and D (p = 0.02, 0.01) and between Groups A and C (p = 0.04, 0.02). PLS-DA analysis showed that the individuals from each group were irregularly distributed according to their clade. Lactobacillus, Bifidobacterium and Ureaplasma were the dominant genera in all groups. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSts) analysis identified 31 Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologs associated with the bacterial communities from the four groups, including membrane transport, folding, sorting and degradation, xenobiotics biodegradation and metabolism, and nucleotide metabolism. We further determined relationships between pregnancy outcomes (Apgar scores) and certain bacterial species. A significant positive correlation was found between Apgar scores and Actinomyces neuii and Anoxybacillus flavithermus in the vagina and cervical canal of pregnant women with cervical incompetence while Bacteroides plebeius, Bifidobacterium pseudopodium and Staphylococcus petrasii in the cervical canal displayed negative correlations with Apgar scores. Moreover, Clostridium fimetarium, Methanobacterium congolense, Pseudomonas chlororaphis, and Psychrobacter nivimaris in the vagina were negatively correlated with Apgar scores. These bacteria may serve as potential biomarkers, however, additional research is warranted to verify their role in clinical outcomes.

The WNW-trending Yangda-Yaxu fault (YYF) is located in the interior of the Qiangtang block (QTB). The YYF cuts through the Nujiang suture and Lancang river suture zone and divides Nujiang fault (NF) and Lancangjiang fault (LCJF) into two sections with significantly different activity levels, suggesting that the YYF may function as a specific structure in this region. In addition, a recent work argues that the YYF plays an important role in strain partitioning in southeastern Tibet and poses a high surface-faulting risk to the Sichuan-Tibet railway. However, no M ≥ 5.0 earthquakes have been recorded, and no palaeoseismic research has been conducted along the fault, leading to limited knowledge regarding its rupture behavior, which is essential for understanding regional tectonic deformation and assessing the regional seismic potential. In this study, we constrained the timings and recurrence intervals of late Quaternary paleoseismic events along the YYF for the first time. Through trench excavations and exposure cleaning combined with radiocarbon dating, five faulting events were identified, namely, E1 through E5 from youngest to oldest (831–1,220, 3,307–6,703, 9,361–10,286, 12,729–14,651, and before 14,651 yr BP). The recurrence interval of major earthquakes along the YYF follows a quasi-periodic pattern with an interval of ∼4,000 yr. Combining the clear linear geomorphic features along the fault and the paleoearthquake results in this paper, we believe that YYF is a newly-generated active fault, and has a significant control effect on the late Quaternary evolution of the NF and the LCJF. Further analysis revealed that the YYF also plays an important role in accommodating crustal deformation.

AbstractIn mainland China, approximately 86% of M≥7 earthquakes have occurred in the block boundary zone, which has been well explained by active block theory. However, a few large earthquakes have occurred within the active block, which provides us with an opportunity to better study the deformation of the Tibetan Plateau. The Litang Fault (LTF) is a strike-slip fault within the Sichuan-Yunnan Active Block and produced the 1948 Litang M7.3 earthquake. We presented the Holocene rupture behavior of the LTF based on detailed field investigations, paleoearthquake trenching, and radiocarbon dating. Specifically, we revealed 13 Holocene paleoearthquake events at four trenching sites and divided these events into 3 rupture cycles at the whole-fault scale. The seismic rupture behavior of the LTF is characterized by recurrent southeastward migration, and since the Holocene, the period of each rupture cycle has decreased rapidly from 8000 years to 500 years. Our results may provide geologic evidence for understanding the intrablock stress patterns and material transfer of the southeastern region of the Tibetan Plateau. The rapidly enhanced fault activity of the LTF since the late Holocene indicates that the LTF may have played an important role in accommodating the deformation of the southeastern region of the Tibetan Plateau.

Under a multiscenario environment with frequent bursts of data in the edge cloud, the resource allocation in the edge cloud will affect the stability of its nodes. To address this problem, a balanced virtual resource allocation model based on conflict conditions is proposed. Based on a thorough study of the similarity between task attributes and resources used by the host, the concept of a task backlog is implemented to achieve a preliminary balanced allocation of tasks; thus, a conflict condition based on the remaining resources of the physical and virtual machines is proposed. Further, a matrix of phased conflict coefficients is built to establish a balanced virtual machine allocation model. The results of experiments comparing the performance of the proposed model with that of other existing models indicate that the proposed model can reduce the virtual machine scheduling time by up to 8.33%, save up to 6.25% of host energy consumption, and improve the algorithm efficiency by 20.47% compared with the other algorithms. To avoid the local optimal problem caused by dynamic virtual machine migration, an improved ant colony algorithm is combined with the above model, and concepts of a pheromone volatility factor and suppression factor are implemented to optimize the pheromone measurement function and ensure that the virtual machine migration path is globally optimal. Overall, the model reduces the conflict rate of resources on the physical machine and can maintain stable operation under CPU usage fluctuation, thus realizing a balanced allocation of node resources.

Acoustic emission (AE) is widely used in engineering and rock mechanics. The algorithm of AE location based on homogeneous medium or single velocity structure is confronted with lower accuracy when it is applied to the actual working conditions that are prevailing complicated and heterogeneous. In this paper, an AE location algorithm based on complex composite structure (CCS) is proposed via carrying out the following studies: (1) A new travel time calculation scheme suitable for CCS with step-like velocity change is proposed based on an optimized shortest path algorithm. By doing this, a reasonable ray path that is only deflected at the interface is obtained to improve the travel time accuracy. The time complexity of the new algorithm is O(nlog2n). (2) The availability of the new algorithm is verified via a theoretical analysis under a one-dimensional velocity structure as well as an AE experiment using a complex structure under artificial excitation. (3) The AE location during the failure of a simulated CCS in the laboratory indicates that the new algorithm can effectively calculate the travel time and ray path of the sample.

Satellite thermal infrared remote sensing has received worldwide attention in earthquake-precursors exploration. Meanwhile, it has also encountered great controversy due to the lack of quantitative interpretation of the observations, despite the existing qualitative physical mechanisms being able to greatly help us understand thermal infrared anomalies. Here, we report a potential mechanism to quantitatively analyze co-seismic thermal infrared anomalies based on temperature change caused by stress variation through theoretical, experimental, and field investigations. This paper firstly deduces theoretically the temperature variation during elastic deformation of rock on the basis of the thermodynamic theory. Secondly, three laboratory experiments on rock samples are conducted to verify the theoretical estimates of the temperature changes caused by stress variations using an infrared camera with the spectral range of 8~12 μm. Thirdly, a mechanical model on thrust faults is built to evaluate the co-seismic temperature drop as a result of thrust faulting. The model shows that the co-seismic temperature drop in rocks should be in the order of 0.18 K. This variation in rock temperature may cause a change in heat equivalent to changes in shallow atmospheric temperatures of 3.0–6.0 K, which is in accordance with the temperature anomalies observed by satellite thermal infrared remote sensing. In addition, the temperature change caused by crustal stress variation may involve a large spatial scale, covering the whole focal area, which has characteristics of regional distribution and is conducive to satellite observation. Therefore, a quantitative explanation of the satellite thermal infrared seismic anomaly mechanism can be given via the temperature change caused by crustal stress variation.

Abstract This paper presents the results of recent research on the interface shear behavior of normal weight and lightweight concrete composite T-beams. In the experimental program 12 beams and necessary control cylinders were tested to provide experimental cases with the variables of interface preparation, clamping stress and lightweight slab concrete strength. Compared with 7 equations developed previously, it has been found that those formulas, especially the ones from current AASHTO and ACI design codes, give a conservative theoretical prediction of horizontal shear capacity of composite T-beams. Based on the experimental results, a more accurate equation was developed to predict the interface shear transfer strength of composite concrete T-beam. By comparing the experimental results of previous beam tests and shear-friction push-off tests for different types of concrete with both rough and smooth interface published in literature, it has been found that the proposed formula is reliable in predicting the horizontal shear strength of concrete composite T-beams.

Fixing imperfections in keyed dry joints between the concrete segments compromise the performance of precast concrete segmental bridges (PCSBs), which needs to consider carefully. In this study, a finite-element model on high-strength concrete single-keyed dry joints in PCSBs was established and validated by experimental results. Parametric studies on fixing imperfections in key, concrete strengths, and confining pressures were carried out based on that model. The numeric results included crack patterns, load–displacements and shear strength. Fixing imperfections—especially at lower surface of keys—reduced shear strength of single-keyed dry joints by the different shear transfer mechanism. Higher confining pressure and concrete strength improved the shear strength, but they mitigated and aggravated the effect of fixing imperfections at lower surface of key on shear strength, respectively. Compared with simulating results, AASHTO standard overestimated the shear capacity of single-keyed dry joints with fixing imperfections at lower surface of key by up to 0.602–22.0%, but greatly underestimated that of the rest. A modified formula with a strength reduction factor was proposed. For six experimental three-keyed dry-joint specimens and 30 numeric single-keyed dry-joint specimens with or without fixing imperfections, the average ratio of code predictions to experimental results was 90.4% and 81.6%, respectively.

Diet is among the most relevant factors affecting gut microbial communities and affects the host gut microbiota composition and function. We investigated the gut fungal communities of Anser erythropus wintering at either Shengjin Lake or Caizi Lake, China, using high-throughput sequencing of the internal transcribed spacer gene region. We retained 1,302,562 valid tags corresponding to 2,102 operational taxonomic units (OTUs) from 20 fecal samples (ten per lake). The OTUs from the Shengjin Lake geese represented 7 phyla, 27 classes, 81 orders, 151 families, and 395 genera; those from the Caizi Lake geese comprised 7 phyla, 28 classes, 73 orders, 133 families, and 232 genera. Ascomycota, Basidiomycota, Zygomycota and Rozellomycota were the dominant gut fungal phyla in the geese. The alpha-diversity indices differed significantly between the Shengjin Lake and Caizi Lake geese. The Shengjin Lake geese ate mainly Poaceae species, whereas the Caizi Lake geese ate mainly Carex spp., suggesting that different diets might induce varied gut fungal communities between the geese. More fungal genera were significantly correlated with bacterial genera (Sphingobacterium, Brevundimonas, Stenotrophomonas, Chryseobacterium, Acinetobacter, and Pseudomonas) in pairwise populations, and Ceratobasidium, Tomentella, Paurocotylis, Tuber, Podospora and Mortierella were the core fungal genera among the geese from both lakes. Nine potentially pathogenic species were identified across all samples, and the relative abundances of potential pathogens were significantly higher in the Shengjin Lake samples than in the Caizi Lake samples. These findings suggest that the gut fungi were highly sensitive to the diets of the geese at both lakes. Potential pathogenic species of A. erythropus should be further studied. [ABSTRACT FROM AUTHOR]

Analyses of modern biomedical data are often complicated by missing values. When variables of interest are missing for some subjects, it is desirable to use observed auxiliary variables, which are sometimes high dimensional, to impute or predict the missing values in order to improve the statistical efficiency. Although many methods have been developed for prediction using high-dimensional variables, it is challenging to perform a valid inference based on such predicted values. In this study, we develop an association test for an outcome variable and a potentially missing covariate, where the covariate can be predicted using variables selected from a set of high-dimensional auxiliary variables. We establish the validity of the test under data-driven model-selection procedures. We also demonstrate the validity of the proposed method and its advantages over existing methods using extensive simulation studies and an application to a major cancer genomics study. [ABSTRACT FROM AUTHOR]