Stabilization of positive switched systems with time-varying delays under asynchronous switching

This paper investigates the state feedback stabilization problem for a class of positive switched systems with time-varying delays under asynchronous switching in the frameworks of continuous-time and discrete-time dynamics. The so-called asynchronous switching means that the switches between the candidate controllers and system modes are asynchronous. By constructing an appropriate co-positive type Lyapunov-Krasovskii functional and further allowing the functional to increase during the running time of active subsystems, sufficient conditions are provided to guarantee the exponential stability of the resulting closed-loop systems, and the corresponding controller gain matrices and admissible switching signals are presented. Finally, two illustrative examples are given to show the effectiveness of the proposed methods

Associations of Educational Attainment, Occupation, Social Class and Major Depressive Disorder among Han Chinese Women

Background The prevalence of major depressive disorder (MDD) is higher in those with low levels of educational attainment, the unemployed and those with low social status. However the extent to which these factors cause MDD is unclear. Most of the available data comes from studies in developed countries, and these findings may not extrapolate to developing countries. Examining the relationship between MDD and socio economic status in China is likely to add to the debate because of the radical economic and social changes occurring in China over the last 30 years. Principal findings We report results from 3,639 Chinese women with recurrent MDD and 3,800 controls. Highly significant odds ratios (ORs) were observed between MDD and full time employment (OR = 0.36, 95% CI = 0.25–0.46, logP = 78), social status (OR = 0.83, 95% CI = 0.77–0.87, logP = 13.3) and education attainment (OR = 0.90, 95% CI = 0.86–0.90, logP = 6.8). We found a monotonic relationship between increasing age and increasing levels of educational attainment. Those with only primary school education have significantly more episodes of MDD (mean 6.5, P-value = 0.009) and have a clinically more severe disorder, while those with higher educational attainment are likely to manifest more comorbid anxiety disorders. Conclusions In China lower socioeconomic position is associated with increased rates of MDD, as it is elsewhere in the world. Significantly more episodes of MDD occur among those with lower educational attainment (rather than longer episodes of disease), consistent with the hypothesis that the lower socioeconomic position increases the likelihood of developing MDD. The phenomenology of MDD varies according to the degree of educational attainment: higher educational attainment not only appears to protect against MDD but alters its presentation, to a more anxious phenotype

Asynchronous L1 control of delayed switched positive systems with mode-dependent average dwell time

This paper investigates the stability and asynchronous L1 control problems for a class of switched positive linear systems (SPLSs) with time-varying delays by using the mode-dependent average dwell time (MDADT) approach. By allowing the co-positive type Lyapunov-Krasovskii functional to increase during the running time of active subsystems, a new stability criterion for the underlying system with MDADT is first derived. Then, the obtained results are extended to study the issue of asynchronous L1 control, where "asynchronous" means that the switching of the controllers has a lag with respect to that of system modes. Sufficient conditions are provided to guarantee that the resulting closed-loop system is exponentially stable and has an L1-gain performance. Finally, two numerical examples are given to show the effectiveness of the developed results. © 2014 Elsevier Inc. All rights reserved

Biological Characteristics of Foam Cell Formation in Smooth Muscle Cells Derived from Bone Marrow Stem Cells

<p>Bone marrow mesenchymal stem cells (BMSC) can differentiate into diverse cell types, including adipogenic, osteogenic, chondrogenic and myogenic lineages. There are lots of BMSC accumulated in atherosclerosis vessels and differentiate into VSMC. However, it is unclear whether VSMC originated from BMSC (BMSC-SMC) could remodel the vessel in new tunica intima or promote the pathogenesis of atherosclerosis. In this study, BMSC were differentiated into VSMC in response to the transforming growth factor &#946; (TGF-&#946;) and shown to express a number of VSMC markers, such as &#945;-smooth muscle actin (&#945;-SMA) and smooth muscle myosin heavy chain1 (SM-MHC1). BMSC-SMC became foam cells after treatment with 80 mg/L ox-LDL for 72 hours. Ox-LDL could upregulate scavenger receptor class A (SR-A) but downregulate the ATP-binding cassette transporter A1 (ABCA1) and caveolin-1 protein expression, suggesting that modulating relative protein activity contributes to smooth muscle foam cell formation in BMSC-SMC. Furthermore, we found that BMSC-SMC have some biological characteristics that are similar to VSMC, such as the ability of proliferation and secretion of extracellular matrix, but, at the same time, retain some biological characteristics of BMSC, such as a high level of migration. These results suggest that BMSC-SMC could be induced to foam cells and be involved in the development of atherosclerosis.</p

Characteristics of volcanic-sedimentary formations and developmental patterns of source and reservoir rocks in an island arc environment of Shibei Sag, Junggar Basin: taking the Carboniferous Jiangbasitao Formation as an example

The Shibei Sag is located in the north of Luliang Uplift in the eastern Junggar Basin. There has been no breakthrough in the exploration of Carboniferous volcanic traps in the Shibei Sag in the past years. Recent drilling of well Zhunbei 6 reveals that the self-generating and self-preserving oil and gas reservoirs in the Carboniferous Jiangbasitao Formation have great exploration potential. However, there is scarce study on this type of reservoir. In order to study the characteristics of volcanic-sedimentary formations and developmental patterns of source and reservoir rocks in an island arc environment of Shibei Sag, the volcanic-sedimentary formations and source rock characteristics of the Jiangbasitao Formation were systematically studied based on previous study, drilling cores, seismic and test data, as well as the analysis of geochemical characteristics of source rocks, and the developmental pattern of volcanic, pyroclastic and source rocks under the control of island arc was established, with the aim of providing theory basis for oil and gas exploration in areas with the same sedimentary background. The results show that the basic volcanic rocks of the Jiangbasitao Formation in the Shibei Sag were formed in an island arc environment related to oceanic subduction. The volcanic formations are mainly composed of near-crater explosive facies, near-crater overflow facies and far-crater explosive facies. The sedimentary formations are dominated by fan delta facies tuffaceous glutenite and sandstone in the franking regions of the island arc and littoral neritic facies tuffaceous mudstone in the low-lying area of the far island arc. The tuffaceous mudstone of the Jiangbasitao Formation is a set of medium source rocks in the mature and high-maturity stages, which have a banding distribution along the northeast-southwest direction with a thickness of 100-500 m. During the sedimentary period of the Jiangbasitao Formation, the volcanic island arc erupted intermittently, and the tuff in the low-lying area of the far island arc and the littoral neritic facies tuffaceous mudstone were interbedded. The tuffaceous mudstones have a good source-reservoir configuration relationship with fan delta glutenite and island arc volcanic rocks. These two types of reservoirs are the key exploration directions in the next step

Hydrocarbon generation and evolution characteristics of Carboniferous source rocks on the northeastern margin of the Junggar Basin and its petroleum geological significance

Various types of source rocks were developed in the Carboniferous trench-arc basin environment on the northeastern margin of the Junggar Basin. In order to implement the efficient hydrocarbon supply area of the main source rocks and guide the oil and gas exploration in this area, researches on the hydrocarbon generation mechanism, potential, evolution process, and hydrocarbon supply characteristics of different types of source rocks were carried out through the combination of geology and geochemistry based on the test data of drilling, organic geochemistry of outcrop source rock samples, and hydrocarbon-generating thermal simulation experiments. The results show that there are three types of source rocks, namely mudstone, tuffaceous mudstone and carbonaceous mudstone in the Carboniferous in the study area. Different source rocks have different parent material composition and activation energy distribution for hydrocarbon generation, and their hydrocarbon generation potential and evolution model have obvious differences. Mudstone generated hydrocarbon rapidly at relatively low maturity stage, tuffaceous mudstone continued to generate hydrocarbon slowly, and carbonaceous mudstone generated hydrocarbon rapidly at relatively higher maturity stage. Later structural transformation, sedimentary filling and geothermal field evolution jointly controlled the thermal evolution process and hydrocarbon supply characteristics of source rocks. Hydrocarbon generation and hydrocarbon loss of source rocks were coupled in time and space, and six hydrocarbon supply models can be divided, i.e., (1) high-efficiency hydrocarbon generation, low hydrocarbon loss, high-efficiency hydrocarbon supply, (2) high-efficiency hydrocarbon generation, relatively high hydrocarbon loss, relatively high-efficiency hydrocarbon supply, (3) relatively high-efficiency hydrocarbon generation, low hydrocarbon loss, relatively high-efficiency hydrocarbon supply, (4) relatively high-efficiency hydrocarbon generation, high hydrocarbon loss, low-efficiency hydrocarbon supply, (5) low-efficiency hydrocarbon generation, high hydrocarbon loss, relatively low-efficiency hydrocarbon supply, and (6) low-efficiency hydrocarbon generation, low hydrocarbon loss, low-efficiency hydrocarbon supply. Among them, the Shibei and Dishuiquan sags are relatively high-efficiency hydrocarbon generation, low hydrocarbon loss and relatively high-efficiency hydrocarbon supply units with material foundation for forming large and medium-sized oil and gas fields, which are the most favorable exploration targets at present

H3K4me3 plays a key role in establishing permissive chromatin states during bud dormancy and bud break in apple

果樹が季節に応答して休眠から目覚めるしくみを解明 --果樹の休眠と発芽におけるヒストン修飾の寄与を解析--. 京都大学プレスリリース. 2022-07-01.Bud dormancy helps woody perennials survive winter and activate robust plant development in the spring. For apple (Malus × domestica), short-term chilling induces bud dormancy in autumn, then prolonged chilling leads to dormancy release and a shift to a quiescent state in winter, with subsequent warm periods promoting bud break in spring. Epigenetic regulation contributes to seasonal responses such as vernalization. However, how histone modifications integrate seasonal cues and internal signals during bud dormancy in woody perennials remains largely unknown. Here, we show that H3K4me3 plays a key role in establishing permissive chromatin states during bud dormancy and bud break in apple. The global changes in gene expression strongly correlated with changes in H3K4me3, but not H3K27me3. High expression of DORMANCY-ASSOCIATED MADS-box (DAM) genes, key regulators of dormancy, in autumn was associated with high H3K4me3 levels. In addition, known DAM/SHORT VEGETATIVE PHASE (SVP) target genes significantly overlapped with H3K4me3-modified genes as bud dormancy progressed. These data suggest that H3K4me3 contributes to the central dormancy circuit, consisting of DAM/SVP and abscisic acid (ABA), in autumn. In winter, the lower expression and H3K4me3 levels at DAMs and gibberellin metabolism genes control chilling-induced release of dormancy. Warming conditions in spring facilitate the expression of genes related to phytohormones, the cell cycle, and cell wall modification by increasing H3K4me3 toward bud break. Our study also revealed that activation of auxin and repression of ABA sensitivity in spring are conditioned at least partly through temperature-mediated epigenetic regulation in winter

Exploration of a Novel Circadian miRNA Pair Signature for Predicting Prognosis of Lung Adenocarcinoma

Lung adenocarcinoma (LUAD) is the primary histological subtype of lung cancer with a markedly heterogeneous prognosis. Therefore, there is an urgent need to identify optimal prognostic biomarkers. We aimed to explore the value of the circadian miRNA (cmiRNA) pair in predicting prognosis and guiding the treatment of LUAD. We first retrieved circadian genes (Cgenes) from the CGDB database, based on which cmiRNAs were predicted using the miRDB and mirDIP databases. The sequencing data of Cgenes and cmiRNAs were retrieved from TCGA and GEO databases. Two random cmiRNAs were matched to a single cmiRNA pair. Finally, univariate Cox proportional hazard analysis, LASSO regression, and multivariate Cox proportional hazard analysis were performed to develop a prognostic signature consisting of seven cmiRNA pairs. The signature exhibited good performance in predicting the overall and progression-free survival. Patients in the high-risk group also showed lower IC50 values for several common chemotherapy and targeted medicines. In addition, we constructed a cmiRNA&ndash;Cgenes network and performed a corresponding Gene Ontology and Gene Set enrichment analysis. In conclusion, the novel circadian-related miRNA pair signature could provide a precise prognostic evaluation with the potential capacity to guide individualized treatment regimens for LUAD

Maternal paraben exposure and intra-pair thyroid-stimulating hormone difference in twin neonates

Thyroid hormones are essential for fetal growth and neurodevelopment. The recent frequent use of parabens has raised concerns about their endocrine-disrupting potential. However, the effects of maternal paraben exposure on neonatal thyroid hormone levels are still largely unknown. In our study, a co-twin control design was employed to analyze the relationships between maternal paraben exposure and neonatal thyroid-stimulating hormone (TSH) difference. We collected information from 252 mother-twin pairs from a twin birth cohort in Wuhan, China. Concentrations of six parabens were measured in maternal urine samples collected at  28 weeks of gestation. Data of neonatal TSH levels were retrieved from medical records. Multiple informant models were applied to explore the time-specific relationships between paraben exposure and intra-twin TSH difference and to determine the susceptible window of exposure. We found that maternal urinary methyl paraben (MeP) during early pregnancy was positively associated with intra-twin TSH difference (%change = 5.96 %; 95 % confidant interval (CI): 0.04 %, 12.2 %). However, no significant differences were observed for exposure to ethyl paraben (EtP) and propyl paraben (PrP), and the associations between parabens and intra-twin TSH difference did not differ materially across pregnancy. Further, a stratified analysis based on twin zygosity and chorionicity and sex types indicated that the positive association between early pregnancy MeP exposure and intra-twin TSH difference was significant in monochorionic diamniotic (MCDA) twins of female-female fetuses and dichorionic diamniotic (DCDA) twins of opposite-sex. The prospective twin study provides first evidence that MeP exposure in early pregnancy was associated with an increased TSH difference in twin neonates, especially in female fetuses