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POLE PlaCEMENT CONTROLLERS FOR LINEAR TIME-DElaY SYSTEMS WITH COMMENSURATE POINT DElaYS

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Analysis in Theory and Applications 2004年第4期20卷 358-372页

作者： M. de la Sen Department of Systems Engineering and Automatic Control Instituto de Investigaction y Desarrollo de Procesos. IIDP Facultad de Ciencias. Universidad Del Pais Vasco Leioa (Bizkaia). Aptdo. 644 de Bilbao 48080-Bilbao Spain

This paper investigates the exact and approximate spectrum assignment properties associated with realizable output-feedback pole-placement type controllers for single-input single-output linear time-invariant time-delay systems with commensurate point delays. The controller synthesis problem is discussed through the solvability of a set of coupled diophantine equations of polynomials. An extra complexity is incorporated to the above design to cancel extra unsuitable dynamics being generated when solving the above diophantine equations. Thus, the complete controller tracks any arbitrary prefixed (either finite or delay-dependent) closed-loop spectrum. However, if the controller is simplified by deleting the above mentioned extra complexity, then the robust stability and approximated spectrum assignment are still achievable for a certain sufficiently small amount of delayed dynamics. Finally, the approximate spectrum assignment and robust stability problems are revisited under plant disturbances if the nominal controller is maintained. In the current approach, the finite spectrum assignment is only considered as a particular case to the designer's choice of a (delay-dependent) arbitrary spectrum assignment objective.

关键词： pole placement controller linear time-delay system controller synthesis problem

Water sorption thermodynamics in glassy polymers endowed with hydrogen bonding interactions

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Science China(Physics,Mechanics & Astronomy) 2020年第4期63卷 136-154页

作者： G.Scherillo P.la Manna P.Musto G.M ensitieri Department of Chemical Materials and Production EngineeringUniversity of Naples Federico Ⅱnaples 80125Italy Institute for Polymers Composites and BiomaterialsNational Research Council of Italypozzuoli(na)80078Italy

In this contribution, we review and critically compare the results of the analyses we have previously performed on water sorption thermodynamics in a series of polyimides. The experimental investigation was performed by combining gravimetric tests and in situ vibrational spectroscopy. A non-equilibrium theory, based on a compressible lattice framework accounting for the glassy state of the polymer and for the occurrence of hydrogen bonding interactions, has been used to interpret data. Information at a molecular level gained by vibrational spectroscopy has been used to tailor the model equations. The main features of water sorption thermodynamics are well captured, qualitatively and quantitatively, by the adopted model which displays a remarkable agreement with experimental results.

关键词： water polyimides sorption thermodynamics

Temporary severe oculomotor nerve palsy after reconstruction of orbital medial wall fracture: a case report of nonfamiliar complication

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International Journal of Ophthalmology(English edition) 2022年第6期15卷 1032-1034页

作者： Yeon Woong Chung Tae Yoon la Department of Ophthalmology St.Vincent's HospitalCollege of Medicinethe Catholic University of KoreaSuwon 16247Republic of Korea

Dear Editor, Commonly known complications following reconstruction of an orbital fracture include diplopia, hemorrhage, and displacement or infection of the orbital implant, and some studies have reported ptosis cause... 详细信息

关键词： fracture orbital dip

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二维γ-GeSe基异质结的电子特性研究

原子与分子物理学报 2025年第5期42卷 175-181页

作者：乔方卿銮乔帅张腊梅商继敏冯世全郑州轻工业大学电子信息学院河南省磁电信息功能材料实验室郑州450002

二维γ-GeSe拥有类似石墨烯的优异导电特性.利用第一性原理,对二维γ-GeSe的结构和电子特性进行了研究;构建了γ-GeSe/SnSe 2异质结,结果表明该异质结是典型的Ⅱ型能带排列.在施加电场后,其带隙值会有明显的增大,但其能带排列类型保持... 详细信息

二维γ-GeSe拥有类似石墨烯的优异导电特性.利用第一性原理,对二维γ-GeSe的结构和电子特性进行了研究;构建了γ-GeSe/SnSe 2异质结,结果表明该异质结是典型的Ⅱ型能带排列.在施加电场后,其带隙值会有明显的增大,但其能带排列类型保持稳定的Ⅱ型能带排列,这种特性表明此异质结具有在太阳能电池领域应用的潜力.构建的γ-GeSe/GaSe异质结具有典型的Ⅰ型能带排列,施加电场对异质结的电子结构影响甚微;但能一直保持稳定的Ⅰ型能带排列,表明该异质结在发光二极管领域和激光器中具有应用潜力.

关键词：二维γ-GeSe 范德瓦尔斯异质结电子特性能带排列

p53 gene in treatment of hepatic carcinoma:Status quo

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World Journal of Gastroenterology 2007年第7期13卷 985-992页

作者： Yong-Song Guan Zi la Lin Yang Qing He Ping Li Department of Radiology and Oncology.West China Hospital ofSichuan University Chengdu 610041 Sichuan Province China

Hepatocellular carcinoma (HCC) is one of the 10 most common cancers worldwide. There is no ideal treatment for HCC yet and many researchers are trying to improve the effects of treatment by changing therapeutic strategies. As the majority of human cancers seem to exhibit either abnormal p53 gene or disrupted p53 gene activation pathways, intervention to restore wild-type p53 (wt-p53) activities is an attractive anti-cancer therapy including HCC. Abnormalities of p53 are also considered a predisposition factor for hepatocarcinogenesis. p53 is frequently mutated in HCC. Most HCCs have defects in the p53-mediated apoptotic pathway although they carry wt-p53. High expression of p53 in vivo may exert therapeutic effects on HCC in two aspects: (1) High expression of exogenous p53 protein induces apoptosis of tumor cells by inhibiting proliferation of cells through several biologic pathways and (2) Exogenous p53 renders HCC more sensitive to some chemotherapeutic agents. Several approaches have been designed for the treatment of HCC via the p53 pathway by restoring the tumor suppression function from inactivation, rescuing the mutated p53 gene from instability, or delivering therapeutic exogenous p53. Products with p53 status as the target have been studied extensively in vitro and in vivo . This review elaborates some therapeutic mechanisms and advances in using recombinant human adenovirus p53 and oncolytic virus products for the treatment of HCC.

关键词： p53 gene Hepatocellular carcinoma Therapeutic strategies Advances Prospects

Supplementation with sodium butyrate improves growth and antioxidant function in dairy calves before weaning

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Journal of Animal Science and Biotechnology 2021年第1期12卷 305-313页

作者： Wenhui Liu Ala Teng Zhu la Alexander Evans Shengtao Gao Zhongtang Yu Dengpan Bu Lu Ma Institute of Animal Science State Key Laboratory of Animal NutritionChinese Academy of Agricultural SciencesNo.2 Yuanmingyuan West RoadBeijing 100193People’s Republic of China School of Agriculture&Food Science University College DublinBelfieldDublin 4Ireland Department of Animal Sciences The Ohio State UniversityColumbusOH 43210USA Joint laboratory on Integrated Crop-Tree-Livestock Systems of the Chinese Academy of Agricultural Sciences(CAAS) Ethiopian Institute of Agricultural Research(EIAR)and World Agroforestry Center(ICRAF)Beijing 100193People’s Republic of China.

Background: There is increasing research interest in using short-chain fatty acids(SCFAs) including butyrate as potential alternatives to antibiotic growth promoters in animal production. This study was conducted to evaluate the effects of supplementation of sodium butyrate(SB) in liquid feeds(milk, milk replacer, and the mixture of both)on the growth performance, rumen fermentation, and serum antioxidant capacity and immunoglobins in dairy calves before weaning. Forty healthy female Holstein calves(4-day-old, 40 ± 5 kg of body weight) were housed in individual hutches and randomly allocated to 1 of 4 treatment groups(n = 10 per group) using the RAND function in Excel. The control group was fed no SB(SB0), while the other three groups were supplemented with 15(SB15),30(SB30), or 45(SB45) g/d of SB mixed into liquid feeds offered. The calves were initially fed milk only(days 2 to 20), then a mixture of milk and milk replacer(days 21 to 23), and finally milk replacer only(days 24 to 60).Results: The SB supplementation enhanced growth and improved feed conversion into body weight gain compared with the SB0 group, and the average daily gain increased quadratically with increasing SB supplementation. No significant effect on rumen pH;concentrations of NH_3-N, individual and total VFAs;or acetate:propionate(A:P) ratio was found during the whole experimental period. Serum glutathione peroxidase activity increased linearly with the increased SB supplementation, while the serum concentration of maleic dialdehyde linearly decreased. Serum concentrations of immunoglobulin A, immunoglobulin G, or immunoglobulin M were not affected by the SB supplementation during the whole experimental ***: Under the conditions of this study, SB supplementation improved growth performance and antioxidant function in pre-weaned dairy calves. We recommended 45 g/d as the optimal level of SB supplementation mixed into liquid feeds(milk or milk replacer) to improve the growth and ant

关键词： Antioxidant activity Calf Immune function Sodium butyrate

The Role of the Solar Cycle in the Relationship Between the North Atlantic Oscillation and Northern Hemisphere Surface Temperatures

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Advances in Atmospheric Sciences 2007年第2期24卷 191-198页

作者： laura DE la TORRE Luis GIMENO Juan Antonio AEL Raquel NIETO Universidad de Vigo Facultad de Ciencias de Ourense 32004OurenseSpain

The North Atlantic Oscillation （NAO） is one of the leading modes of climate variability in the Northern Hemisphere. It has been shown that it clearly relates to changes in meteorological variables, such as surface temperature, at hemispherical scales. However, recent studies have revealed that the NAO spatial pattern also depends upon solar forcing. Therefore, its effects on meteorological variables must vary depending upon this factor. Moreover, it could be that the Sun affects climate through variability patterns, a hypothesis that is the focus of this study. We find that the relationship between the NAO/AO and hemispheric temperature varies depending upon solar activity. The results show a positive significant correlation only when solar activity is high. Also, the results support the idea that solar activity influences tropospheric climate fluctuations in the Northern Hemisphere via the fluctuations of the stratospheric polar vortex .

关键词： solar activity North Atlantic Oscillation Arctic Oscillation Northern Hemisphere surface temperature

Benefits of minimally invasive surgery in the treatment of gastric cancer

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World Journal of Gastroenterology 2022年第30期28卷 4227-4230页

作者： Simone Sibio Francesca la Rovere Sara Di Carlo Department of Surgery P.Valdoni Unit of Oncologic and Minimally Invasive SurgerySapienza University of RomeUmberto I University HospitalRome 00161Italy Minimally Invasive Surgery Unit Department of SurgeryTor Vergata UniversityRome 00133Italy

We read with great interest the article that retrospectively analyzed 814 patients with primary gastric cancer,who underwent minimally invasive R0 gastrectomy between 2009 and 2014 by grouping them in laparoscopic vs robotic *** results of the study highlighted that age,American Society of Anesthesiologists status,gastrectomy type and pathological T and N status were the main prognostic factors of minimally invasive gastrectomy and showed how the robotic approach may improve long-term outcomes of advanced gastric *** to most of the current literature,robotic surgery is associated with a statistically longer operating time when compared to open and laparoscopic surgery;however,looking at the adequacy of resection,defined by negative surgical margins and number of lymph nodes removed,it seems that robotic surgery gives better results in terms of the 5-year overall survival and recurrencefree *** robotic approach to gastric cancer surgery aims to overcome the difficulties and technical limitations of laparoscopy in major *** threedimensional vision,articulation of the instruments and good ergonomics for the surgeon allow for accurate and precise movements which facilitate the complex steps of surgery such as lymph node dissection,esophagus-jejunal anastomosis packaging and reproducing the technical accuracy of open *** the literature,as well as the analyzed study,offers us countless data regarding the short-term oncological results of robotic surgery in the treatment of gastric cancer,satisfactory data on long-term follow-up are lacking,so future studies are necessary.

关键词： Gastric cancer Robotic gastrectomy laparoscopy D2 lymphadenectomy Long-term outcomes Morbidity

Pulsed export of carbon in the north-western Mediterranean Sea

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Journal of Oceanology and Limnology 2023年第1期41卷 189-202页

作者： michel DENIS Dominique LEFEVRE Melilotus THYSSEN Ian RJENKINSON Gérald GRÉGORI Aix Marseille Université Universitéde ToulonCNRS/INSUIRDInstitut Méditerranéen d'Océanologie(MIO)Marseille cedex09 13288France Key laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Agency for Consultation and Research in Oceanography Lavergne19320 La Roche CanillacFrance

The short term(hourly scale)variability of heterotrophic prokaryote(HP)vertical distribution and respiratory activity,was investigated in the north-western(NW)Mediterranean *** vertical distribution was determined on board by flow cytometry analysis of seawater samples collected by series of CTD *** counts and viability were determined for all *** respiratory rates were determined later in the laboratory from filtered seawater samples(23 dm^(3))from 300-1150-m *** average cell viability was 94.8%±2.2%(n=240).There was no accumulation of dead cells,due to quick decay of damaged *** the epipelagic layer,three HP groups were distinguished,two(HNA1,HNA2)who se cells exhibited a high nucleic acid content and one(LNA)with low nucleic acid content ***2 was most populated at 50 m but not detected at 90 m and below,presumably aerobic anoxygenic photoheterotrophic bacteria(AAPs).The variability in HP abundance was mainly confined in the upper 80 m.A few secondary peaks of HP abundance were observed(80-150 m)in connection with abundance troughs in the surface *** cells were continuously present in a wide layer around 500 m(mean 191×10^(3)cells/cm^(3)).Below this layer,HP abundance randomly exhibited peaks,coupled to respiratory rate *** HP abundance and variability in the water column was suppressed during a strong wind *** observed sporadic variability was tentatively interpreted through a pulsed carbon-export mechanism induced by the microorganism production of dissolved poly saccharide s,followed by flocculation and rapid *** mechanism would thus contribute to(ⅰ)preventing organic matter accumulation in the epipelagic layer,(ⅱ)seeding the water column with live HP cells,and(ⅲ)supplying the aphotic water column with fre sh and labile organic *** important vertical flux mechanism needs further observations and modelling.

关键词： north-western Mediterranean Sea heterotrophic prokaryote(HP) cell viability cell respiration transparent exopolymeric particle(TEP) aggregation flow cytometry