Sliding mode control of time‐varying delay Markov jump with quantized output

This paper investigates the quantized sliding mode control of Markov jump systems with time‐varying delay. A dynamical adjustment law is explored to quantize the system output. By constructing an observer‐based integral sliding surface, a sliding mode controller is designed to take over the dynamical motion of state estimation and ensure the reachability of sliding surface. A new scaling manner is developed to build the bound between the system output and quantized error. With the help of separation strategies for controller synthesis and general transition probabilities and a lower bound theorem for nonlinear integral terms, a new synthesis method to ensure the required stability and meet the required performance is proposed in the form of linear matrix inequalities. The validity of the proposed control method is illustrated by a numerical example.     

Investigation of the mechanisms of Genkwa Flos hepatotoxicity by a cell metabolomics strategy combined with serum pharmacology in HL-7702 liver cells

1. To investigate Genkwa Flos hepatotoxicity, a cell metabolomics strategy combined with serum pharmacology was performed on human HL-7702 liver cells in this study.

2. Firstly, cell viability and biochemical indicators were determined and the cell morphology was observed to confirm the cell injury and develop a cell hepatotoxicity model. Then, with the help of cell metabolomics based on UPLC-MS, the Genkwa Flos group samples were completely separated from the blank group samples in the score plots and seven upregulated as well as two down-regulated putative biomarkers in the loading plot were identified and confirmed. Besides, two signal molecules and four enzymes involved in biosynthesis pathway of lysophosphatidylcholine and the sphingosine kinase/sphingosine-1-phosphate pathway were determined to investigate the relationship between Genkwa Flos hepatotoxicity and these two classic pathways. Finally, the metabolic pathways related to specific biomarkers and two classic metabolic pathways were analyzed to explain the possible mechanism of Genkwa Flos hepatotoxicity.

3. Based on the results, lipid peroxidation and oxidative stress, phospholipase A₂/lysophosphatidylcholine pathway, the disturbance of sphingosine-1-phosphate metabolic profile centered on sphingosine kinase/sphingosine-1-phosphate pathway and fatty acid metabolism might be critical participators in the progression of liver injury induced by Genkwa Flos.     

腹腔镜肝癌根治术的热点与未来发展

随着腹腔镜肝切除技术的发展与推广，腹腔镜肝切除中的一些难点，如术中出血的控制、解剖性肝切除、巨大肝癌切除、腹腔镜下联合肝脏分割与门静脉支结扎的二步肝切除术(ALPPS)等方面均基本解决。术中超声与荧光染色技术也得到普及。本文就上述问题做一概述，并对腹腔镜肝切除未来发展提出思路，以进一步推动我国腹腔镜肝切除的技术进步。     

Mimengosides J and K: two new neuroprotective triterpenoids from the fruits of Buddleja lindleyana

Two new 11-methoxyl substituted triterpenoids, named as mimengosides J (1) and K (2), along with seven known compounds, were isolated from the fruits of Buddleja lindleyana. Their structures were elucidated on the basis of spectroscopic analysis. In addition, the new ones were evaluated for protective effects against damage of SH-SY5Y cells induced by 1-methyl-4-phenylpyridinium ion (MPP⁺) and the results indicated that those may be one of the candidate compositions of Buddleja lindleyana for the treatment of neurodegenerative disease.

     

肝段或肝叶切除术对肝内胆管结石再次手术效果的影响

目的对比不同术式对肝内胆管结石再次手术效果，探讨肝段或肝叶切除术的优势。 方法回顾性分析2011年8月至2014年8月收治的79例肝内胆管结石再次手术患者资料，依据术式不同分为肝段(叶)切除术组(甲组，n＝38)和非肝段(叶)切除术组(乙组，n＝41)两组。应用SPSS 19.0软件对所有临床数据进行统计学分析，手术相关指标等以( ±s)的形式表示，组间比较采用独立t检验；术后并发症发生情况及预后情况等计数资料以例(%)的形式表示，采用χ²检验；P<0.05差异有统计学意义。 结果两组患者术中出血量、手术时间及术后住院时间相比，差异无统计学意义(P>0.05)；甲组患者的术后并发症发生率5.3%(2/38)显著低于乙组22.0%(9/41)(P<0.05)；甲组残留结石发生率、症状复发率2.6%(1/38)、 0(0/41)均显著低于乙组17.1%(7/41)、 12.2%(5/41)(P<0.05)，差异有统计学意义(P<0.05)；但两组患者的病死率2.6%(1/38)和0(0/41)相比，差异无统计学意义(P>0.05)。 结论肝段(叶)切除术能够有效改善肝内胆管结石再次手术效果，值得推广。     

Factors associated with provision of depot medroxyprogesterone acetate to adolescents by US health care providers

ObjectiveIdentify factors associated with healthcare providers' frequency of depot medroxyprogesterone acetate (DMPA) provision to adolescents.Study designWe analyzed data from surveys mailed to a nationally representative sample of public-sector providers and office-based physicians (n=1984). We estimated adjusted odds ratios (aORs) and 95% confidence intervals (CIs) of factors associated with frequent DMPA provision to adolescents in the past year.ResultsAlthough most providers (>95%) considered DMPA safe for adolescents, fewer reported frequent provision (89% of public-sector providers; 64% of office-based physicians). Among public-sector providers, factors associated with lower odds of frequent provision included working in settings without Title X funding (aOR 0.44, 95% CI 0.30–0.64), reporting primary care as their primary clinical focus versus reproductive or adolescent health (aOR 0.42, 95% CI 0.28–0.61), and providing fewer patients with family planning services. Among office-based physicians, factors associated with lower odds of frequent provision included specializing in obstetrics/gynecology (aOR 0.50, 95% CI 0.27–0.91) and family medicine (aOR 0.21, 95% CI 0.09–0.47) versus adolescent medicine, completing training ≥15 versus <5 years ago (aOR 0.27, 95% CI 0.09–0.83), and reporting that 0–24% of patients pay with Medicaid or other government healthcare assistance versus ≥50% (aOR 0.23, 95% CI 0.09–0.61). The reason most commonly reported by providers for infrequent DMPA provision was patient preference for another method.ConclusionsWhile most providers reported frequently providing DMPA to adolescents, training on evidence-based recommendations for contraception, focused on subgroups of providers with lower odds of frequent DMPA provision, may increase adolescents' access to contraception.ImplicationsAlthough >95% of providers considered depot medroxyprogesterone (DMPA) a safe contraceptive for adolescents, only 89% of public-sector providers and 64% of office-based physicians reported frequently providing DMPA to adolescents. Provider training on evidence-based recommendations for contraception counseling and provision may increase adolescents' access to DMPA and all methods of contraception.