The plateau pika has multiple benefits for alpine grassland ecosystem in Qinghai–Tibet Plateau

The plateau pika (Ochotona curzoniae) has been engaged in pest control for many years based on the logic that the plateau pika is responsible for alpine grassland degradation and competes with livestock for forage resources. However, the plateau pika is an important species which has multiple benefits in Qinghai-Tibetan Plateau, as it (i) makes burrows that are the primary homes for lizards and a variety of small birds; (ii) creates microhabitat disturbance that promotes the increase of plant species richness; (iii) serves as the principal prey for almost all of the plateau predator species; and (iv) contributes positively to the dynamic equilibrium of alpine ecosystems

Nonlinear Control of Axisymmetric Swirling Flows in a Long Finite-Length Pipe

Feedback stabilization of inviscid and high Reynolds number, axisymmetric, swirling flows in a long finite-length circular pipe using active variations of pipe geometry as a function of the evolving inlet radial velocity is studied. The complicated dynamics of the natural flow requires that any theoretical model that attempts to control vortex stability must include the essential nonlinear dynamics of the perturbation modes. In addition, the control methodology must establish a stable desired state with a wide basin of attraction. The present approach is built on a weakly nonlinear model problem for the analysis of perturbation dynamics on near-critical swirling flows in a slightly area-varying, long, circular pipe with unsteady changes of wall geometry. In the natural case with no control, flows with incoming swirl ratio above a critical level are unstable and rapidly evolve to either vortex breakdown states or accelerated flow states. Following an integration of the model equation, a perturbation kinetic-energy identity is derived, and an active feedback control methodology to suppress perturbations from a desired columnar state is proposed. The stabilization of both inviscid and high-Re flows is demonstrated for a wide range of swirl ratios above the critical swirl for vortex breakdown and for largeamplitude initial perturbations. The control gain for the fastest decay of perturbations is found to be a function of the swirl level. Large gain values are required at near-critical swirl ratios while lower gains provide a successful control at swirl levels away from critical. This feedback control technique cuts the feed-forward mechanism between the inlet radial velocity and the growth of perturbation's kinetic energy in the bulk and thereby enforces the decay of perturbations and eliminates the natural explosive evolution of the vortex breakdown process. The application of this proposed robust active feedback control method establishes a branch of columnar states with a wide basin of attraction for swirl ratios up to at least 50% above the critical swirl. This study provides guidelines for future flow control simulations and experiments. However, the present methodology is limited to the control of high-Reynolds number (nearly inviscid), axisymmetric, weakly nonparallel flows in long pipes

Effects of Dietary Protein Levels on Growth Performance, Carcass Traits, Serum Metabolites, and Meat Composition of Tibetan Sheep during the Cold Season on the Qinghai-Tibetan Plateau

Dietary protein is a critical nutrient that directly influences the health and production of livestock. Recent studies showed that protein supplements could enhance the growth performance of Tibetan sheep. However, there is a lack of information regarding the influence of dietary protein levels on carcass traits and meat composition. This study investigated the effects of dietary protein levels on growth performance, carcass traits, serum metabolites, and meat composition in Tibetan sheep during the cold season on the Qinghai-Tibetan Plateau. A total of eighteen 1-year-old, healthy, castrated Tibetan sheep with similar initial body weights (31.7 ± 0.72 kg) were randomly divided into three treatment groups with different dietary protein level (low protein (LP, 10.1%); medium protein (MP, 12.1%); high protein (HP, 14.1%)) diets. The results indicated that the Tibetan sheep fed with the MP and HP diets had greater final body weights (BWs), average daily gains (ADGs), and average daily feed intakes (ADFIs) (p < 0.05). The MP and HP diets also improved the hot carcass weight, net meat (including the fat) weight, and bone weight of the sheep significantly (p < 0.05). Besides, the dietary protein levels could significantly affect the serum concentrations of growth hormone (p < 0.05). The diameter of muscle fibers in the MP group was significantly greater than that in the LP group (p < 0.05), while the density of muscle fibers showed the opposite trend. The dietary protein levels only significantly (p < 0.05) influenced the ether extract content and profile content of the longissimus dorsi muscle but had no effect on other parameters of meat composition. In summary, our results indicate that dietary protein levels affect growth performance, carcass traits, and meat composition and that diets containing 12.1% and 14.1% protein are recommended to obtain better production performance and meat products in Tibetan sheep, rather than a diet containing 10.1% protein, during the cold season on the Qinghai-Tibetan Plateau

Appendix A. A table of tree abundance and basal area of the five species used in manipulative experiments in the 6 ha plots, and figures showing a sketch map for experimental design in the laboratory, a sketch map for experimental design in the field, density effect in the control treatment and the sterilization treatment as a function of basal area of adult trees in the 6 ha plots, and density effects in the control treatment and the fungicide treatment as a function of basal area of adult...

A table of tree abundance and basal area of the five species used in manipulative experiments in the 6 ha plots, and figures showing a sketch map for experimental design in the laboratory, a sketch map for experimental design in the field, density effect in the control treatment and the sterilization treatment as a function of basal area of adult trees in the 6 ha plots, and density effects in the control treatment and the fungicide treatment as a function of basal area of adult trees in the 6 ha plots

Rapid response with good toleration of sirolimus for life‐threatening neonatal lymphatic malformations

ABSTRACT Introduction Lymphatic malformations (LMs) are rare vascular anomalies predominantly affecting infants, which can be debilitating or life‐threatening when complicated with intralesional bleeding or infection. Effective and safe management strategies are essential in such cases. Case presentation We report a case series involving four Chinese neonates with life‐threatening LMs, initially treated with oral sirolimus. All patients achieved rapid relief and sustained remission, using a lower sirolimus dosage than previously recommended. Furthermore, adverse events were rarely recorded during follow‐up. Conclusion Sirolimus can be considered a promising choice for neonates with intricate and life‐threatening LMs. Initiation with a reduced sirolimus dose is advisable

Effects of winter barn feeding and grazing on growth performance, meat quality and rumen fungal community of Tibetan sheep

The grazing grassland ecosystem on the Qinghai-Tibetan Plateau is highly impacted by seasonal temperature variations. During the long cold season, the biomass and nutrient contents of forage grass do not meet the nutritional needs of grazing livestock and seriously affect growth performance and livestock products. This study investigated different feeding strategies on growth performance, meat quality and rumen fungal community of Tibetan sheep in the winter. Twelve one-year-old healthy castrated Tibetan sheep with similar initial body weights were randomly grouped into traditional grazing (TG) and barn feeding (BF) groups. The TG sheep were labelled and grazed on the local cool-season pasture without feed supplementing, while BF sheep were fed a mixed diet in feeding shed. Compared with the TG group, significantly increased body weight and average daily weight gain (ADG) were observed in the BF group (p < 0.001), which resulted in a significant increase in the hot carcase weight, net meat weight, carcase rate and net meat rate (p < 0.01). Moreover, the longissimus dorsi muscle of the BF group showed significantly increased muscle fibre diameter, perimeter, and area and increased crude protein and ether extract contents (p < 0.01), while the meat tenderness and amino acid content were reduced. ITS high-throughput sequencing showed that Ascomycota was the predominant fungal phylum in the rumen of Tibetan sheep. At the genus level, the rumen of TG sheep presented higher proportions of Preussia, Anaeromyces and Pilidium, while the most abundant genera in the BF sheep were Penicillium, Acaulium and Vishniacozyma. In summary, BF strategy enhanced the relative abundance of several dominant fungal genera related to the nutrient absorption and metabolism capacity, and effectively improves the growth and slaughter performance and affects meat quality of Tibetan sheep in the winter

The allotetraploid horseradish genome provides insights into subgenome diversification and formation of critical traits

Abstract Polyploidization can provide a wealth of genetic variation for adaptive evolution and speciation, but understanding the mechanisms of subgenome evolution as well as its dynamics and ultimate consequences remains elusive. Here, we report the telomere-to-telomere (T2T) gap-free reference genome of allotetraploid horseradish (Armoracia rusticana) sequenced using a comprehensive strategy. The (epi)genomic architecture and 3D chromatin structure of the A and B subgenomes differ significantly, suggesting that both the dynamics of the dominant long terminal repeat retrotransposons and DNA methylation have played critical roles in subgenome diversification. Investigation of the genetic basis of biosynthesis of glucosinolates (GSLs) and horseradish peroxidases reveals both the important role of polyploidization and subgenome differentiation in shaping the key traits. Continuous duplication and divergence of essential genes of GSL biosynthesis (e.g., FMO GS-OX , IGMT, and GH1 gene family) contribute to the broad GSL profile in horseradish. Overall, the T2T assembly of the allotetraploid horseradish genome expands our understanding of polyploid genome evolution and provides a fundamental genetic resource for breeding and genetic improvement of horseradish

Transcriptional Memory in Taraxacum mongolicum in Response to Long-Term Different Grazing Intensities

Grazing, as an important land use method in grassland, has a significant impact on the morphological and physiological traits of plants. However, little is known about how the molecular mechanism of plant responds to different grazing intensities. Here, we investigated the response of Taraxacum mongolicum to light grazing and heavy grazing intensities in comparison with a non-grazing control. Using de novo transcriptome assembly, T. mongolicum leaves were compared for the expression of the different genes under different grazing intensities in natural grassland. In total, 194,253 transcripts were de novo assembled and comprised in nine leaf tissues. Among them, 11,134 and 9058 genes were differentially expressed in light grazing and heavy grazing grassland separately, with 5867 genes that were identified as co-expression genes in two grazing treatments. The Nr, SwissProt, String, GO, KEGG, and COG analyses by BLASTx searches were performed to determine and further understand the biological functions of those differentially expressed genes (DEGs). Analysis of the expression patterns of 10 DEGs by quantitative real-time RT-PCR (qRT-PCR) confirmed the accuracy of the RNA-Seq results. Based on a comparative transcriptome analysis, the most significant transcriptomic changes that were observed under grazing intensity were related to plant hormone and signal transduction pathways, carbohydrate and secondary metabolism, and photosynthesis. In addition, heavy grazing resulted in a stronger transcriptomic response compared with light grazing through increasing the of the secondary metabolism- and photosynthesis-related genes. These changes in key pathways and related genes suggest that they may synergistically respond to grazing to increase the resilience and stress tolerance of T. mongolicum. Our findings provide important clues for improving grassland use and protection and understanding the molecular mechanisms of plant response to grazing