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Morphology and structure of plants are the results from the joint action of itself and the external environment. In order to analyze the correlation between tree shape structure and leaf trait of Bombax ceiba, and to explore the influence of topographic, soil, and meteorological elements on its growth shape, and to reveal its growth strategy and adaptation mechanism, we studied 230 B. ceiba trees in Xishuangbanna National Nature Reserve of Yunnan Province and measured six tree shape structure indexes, eight leaf trait indexes, and habitat elements of regional topographic, meteorology, and soil. The effects and explantation of habitat elements on tree shape structure and leaf trait of B. ceiba were analyzed by structural equation model and variation decomposition. The results were as follows: (1) There were correlations among the indexes of tree shape structure and among the indexes of leaf trait (P < 0.05). (2) The observed indexes of habitat elements had a strong influence on the growth indexes of B. ceiba leaves. The mean annual precipitation, slope and average temperature had a higher interpretation rate on the growth indexes of B. ceiba leaves, and were the dominant habitat indexes affecting the growth of B. ceiba. (3) According to the standardized path coefficient, the three habitat elements had the same effects on tree shape structure and leaf trait of B. ceiba, and all of them were in the order of topographic element>meteorological element>soil element. (4) The superposition of three habitat elements explained that tree shape structure and leaf trait were 43.5% and 12.3%, respectively, indicating that the response of tree shape structure to habitat environment was greater than that of leaf trait to environment. The results of this study preliminarily explore the adaptation strategies of different growth indexes to environmental elements of B. ceiba, which provides theoretical basis and practical reference for the cultivation and propagation of B. ceiba in heterogeneous habitats and efficient management of B. ceiba plantation.

Sex chromosomes evolved from autosomes many times across the eukaryote phylogeny. Several models have been proposed to explain this transition, some involving male and female sterility mutations linked in a region of suppressed recombination between X and Y (or Z/W, U/V) chromosomes. Comparative and experimental analysis of a reference genome assembly for a double haploid YY male garden asparagus (Asparagus officinalis L.) individual implicates separate but linked genes as responsible for sex determination. Dioecy has evolved recently within Asparagus and sex chromosomes are cytogenetically identical with the Y, harboring a megabase segment that is missing from the X. We show that deletion of this entire region results in a male-to-female conversion, whereas loss of a single suppressor of female development drives male-to-hermaphrodite conversion. A single copy anther-specific gene with a male sterile Arabidopsis knockout phenotype is also in the Y-specific region, supporting a two-gene model for sex chromosome evolution.

Abstract Background Noninvasive prenatal testing (NIPT) has been widely used clinically to detect fetal chromosomal aneuploidy with high accuracy rates, gradually replacing traditional serological screening. However, the application of NIPT for monogenic diseases is still in an immature stage of exploration. The detection of mutations in peripheral blood of pregnant women requires precise qualitative and quantitative techniques, which limits its application. The bioinformatic strategies based on the SNP (single nucleotide polymorphism) linkage analysis are more practical, which can be divided into two types depending on whether proband information is needed. Hidden Markov Mode (HMM) and Sequential probability ratio test (SPRT) are suitable for families with probands. In contrast, methods based on databases and population demographic information are suitable for families without probands. Methods In this study, we proposed a Spearman rank correlation analysis method to infer the fetal haplotypes based on core family information. Allele frequencies of SNPs that were used to construct parental haplotypes were calculated as sets of nonparametric variables, in contrast to their theoretical values represented by a fetal fraction (FF). The effects on the calculation of the fetal concentration of two DNA enrichment methods, multiple‐PCR amplification, and targeted hybrid capture, were compared, and the heterozygosity distribution of SNPs within pedigrees was analyzed to reveal the best conditions for the model application. Results Predictions of the paternal haplotype inheritance were in line with expectations for both DNA library construction methods, while for maternal haplotype inheritance prediction, the rates were 96.55% for method multiple‐PCR amplification and 95.8% for method targeted hybrid capture. Conclusion Positive prediction rates showed that the maternal haplotype prediction was not as accurate as paternal one, due to the large amount of maternal noise in the mother's peripheral blood. Although this model is relatively immature, it provides a new perspective for noninvasive prenatal clinical tests of monogenic diseases.

Background: Circular RNAs (circRNAs) exhibit unique patterns of expression and high levels of stability in patient plasma samples such that they represent ideal non-invasive biomarkers that can be leveraged to detect a wide array of diseases including endometrial cancer (EC). This study was designed to identify circRNAs with potential diagnostic utility in serum samples from EC patients while also evaluating the utility of macrophage migration inhibitory factor (MIF) as a biomarker when screening for this form of cancer in the clinic. Methods: Levels of circEPSTI1 and MIF were assessed in the plasma of EC patients and healthy subjects (n=186 each) through qPCR and ELISAs. The diagnostic utility of these biomarkers was assessed with receiver operating characteristic curve (ROC) analyses. Results: Relative to healthy subjects, EC patient serum contained significantly elevated circEPSTI1 and MIF. An association was noted between circEPSTI1 expression in stages, histologic grade, and residual tumor. ROC curves confirmed that serum circEPSTI1 levels distinguished between controls and patients with EC with an Area of 0.835 and serum MIF levels distinguished between controls and patients with EC with an Area of 0.6646. When instead diagnosing patients based on the combination of MIF and circEPSTI1, the Area further rose to 0.8604. Conclusion: Assessing the combination of circEPSTI1 and MIF may be a viable approach to reliably diagnosing EC. [ABSTRACT FROM AUTHOR]

Network feedback in a congestion-control system is subject to delay, which can significantly affect stability and performance of the entire system. While most existing stability conditions explicitly depend on delay [D.sub.i] of individual flow i, a recent study [1] shows that the combination of a symmetric Jacobian A and condition p(A) < 1 guarantees local stability of the system regardless of [D.sub.i]. However, the requirement of symmetry is very conservative and no further results have been obtained beyond this point. In this technical note, we proceed in this direction and gain a better understanding of conditions under which congestion-control systems can achieve delay-independent stability. Towards this end, we first prove that if Jacobian matrix A satisfies [parallel] A [parallel] < 1 for any monotonic induced matrix norm [parallel] x [parallel], the system is locally stable under arbitrary diagonal delay [D.sub.i]. We then derive a more generic result and prove that delay-independent stability is guaranteed as long as A is Schur diagonally stable [2], which is also observed to be a necessary condition in simulations. Utilizing these results, we identify several classes of well-known matrices that are stable under diagonal delays if [rho](A) < 1 and prove stability of MKC [1] with arbitrary parameters [[alpha].sub.i] and [[beta].sub.i]. Index Terms--Delay-independent stability, diagonal delay, max-min congestion control.

Stability proofs of nonlinear congestion control systems under heterogeneous feedback delays are usually difficult and involve a fair amount of effort. In this paper, we show that there exist a class of congestion control methods that admit very simple proofs of asymptotic stability and allow control equations to be delay-independent. This is in contrast to most previous work, which requires that each flow land sometimes each router) adapt its control-loop constants based on the feedback delay and/or the length of the corresponding end-to-end path. Our new congestion control method, which we call Max-Min Kelly Control (MKC), builds upon Kelly's original work in [3] and allows end-flows to be stable and fair regardless of network feedback delays or the number of hops in their end-to-end paths. Using basic matrix algebra and discrete control theory, we show MKC's local asymptotic stability under heterogeneous, directional feedback delays. We also offer a simple proof of its global asymptotic stability assuming constant feedback delay. Index Terms--Asymptotic stability, congestion control, delay.