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Dissecting symbiosis cell by cell

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Molecular Plant 2023年第2期16卷 308-309页

作者： Manuel frank Dugald Reid Department of Molecular Biology and Genetics Aarhus UniversityUniversitetsbyen 818000Aarhus CDenmark Department of Animal Plant and Soil SciencesSchool of AgricultureBiomedicine and EnvironmentLa Trobe UniversityMelbourneVIC 3086Australia

Symbiotic nitrogen fixation in legumes occurs in specialized root organs called *** development requires coordination across tissues as infection progresses from the epidermis to growing nodules derived from the cortex or ***,functional nodules include a variety of specialized cells,including those that house the nitrogen-fixing *** combination of developmental changes across tissues and specialized functions acquired by nodule cells makes dissecting the process difficult using bulk analysis of gene expression,proteins,and metabolites.

关键词： organs cortex specialized

Influence of groundwater depth on species composition and community structure in the transition zone of Cele oasis

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Journal of Arid Land 2010年第4期2卷 235-242页

作者： frank M. THOMAS Department of Geobotany University of Trier Behringstraβe 21 54296 Trier Germany

The paper analyzes the hypothesis that the distribution of dominant plant species and characteristics of plant communities are related to groundwater depth. The results showed that variations of groundwater depth impacted distributions and characteristics of dominant plant communities. However, besides groundwater depth, the community composition and species diversity were also influenced by physiognomy of the habitat. Based on the similarity coefficient, the differences between dominant plant communities were significant at different groundwater depths. Compared with other results relating to desert vegetation and groundwater depth, variations of community distribution were similar at the large spatial scale. However, in this extremely arid region, there were significant differences in community type and community succession when compared with other arid regions, especially in relationship to deep groundwater depth. With groundwater depth from deep to shallow, communities transformed with the sequence of Alhagi communities, Tamarix spp. communities, Populus communities, Phragmites communities, and Sophora communities. At groundwater depth of less than 6.0 m, the community type and composition changed, and the species diversity increased. Among these dominant species, Tamarix exhibited the biggest efficiency in resource utilization according to niche breadth, which means it possessed the best adaptability to environmental conditions at the oasis margins.

关键词： groundwater depth community characteristic niche breadth oases Taklamakan desert

Hollow ion atomic structure and X-ray emission in dense hot plasmas

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Matter and Radiation at Extremes 2024年第6期9卷 43-52页

作者： frank B.Rosmej Christopher J.Fontes Sorbonne University Faculty of Science and EngineeringUMR 7605Case 1284 Place JussieuF-75252 ParisFrance Ecole Polytechnique LULIAtomic Physics in Dense PlasmasRoute de SaclayF-91129 PalaiseauFrance Computational Physics Division Los Alamos National LaboratoryLos AlamosNew Mexico 87545USA

Hollow ion X-ray emission is of great interest in high-energy-density research,since negligible opacity allows studies from the interior of very dense *** this paper,ionization potential depressions of the isoelectronic sequences for single and double K-shell vacancies are obtained from a pure ab initio multiconfiguration Hartree-Fock simulation including exact exchange terms and finite temperature dense plasma *** is demonstrated that the simultaneous representation of these ab initio data in the form of a map of hollow ion X-ray transition energies enables identification of important steps in the matter evolution and ionization *** along the isoelectronic sequence as a function of the pumping energy of a X-ray free electron laser also enables visualization of the impact of ionization potential depression on the pathways of hollow ion formation.

关键词： enable interior steps

Hepatic macrophages in liver homeostasis and diseasesdiversity,plasticity and therapeutic opportunities

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Cellular & Molecular Immunology 2021年第1期18卷 45-56页

作者： Yankai Wen Joeri Lambrecht Cynthia Ju frank Tacke Department of Anesthesiology McGovern Medical SchoolUniversity of Texas Health Science Center at HoustonHoustonTXUSA Department of Hepatology and Gastroenterology Charity University Medicine BerlinBerlinGermany

Macrophages,which are key cellular components of the liver,have emerged as essential players in the maintenance of hepatic homeostasis and in injury and repair processes in acute and chronic liver *** liver injury,resident Kupffer cells(KCs)sense disturbances in homeostasis,interact with hepatic cell populations and release chemokines to recruit circulating leukocytes,including monocytes,which subsequently differentiate into monocyte-derived macrophages(MoMφs)in the *** KCs and MoMφs contribute to both the progression and resolution of tissue inflammation and injury in various liver *** diversity of hepatic macrophage subsets and their plasticity explain their different functional responses in distinct liver *** this review,we highlight novel findings regarding the origins and functions of hepatic macrophages and discuss the potential of targeting macrophages as a therapeutic strategy for liver disease.

关键词： Kupffer cells monocyte-derived macrophages liver inflammation liver fibrosis liver cancer

Energy Management of Echelon Flying Northern Bald Ibises with Different Wingspans and Variable Wingtip Spacing

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Journal of Bionic Engineering 2022年第1期19卷 44-61页

作者： Mostafa Hassanalian Amir Mirzaeinia Niyem Bawana frank Heppner Department of Mechanical Engineering New Mexico TechSocorroNM87801USA Department of Computer Science and Engineering New Mexico TechSocorroNM87801USA Department of Biological Sciences University of Rhode IslandKingstonRI02881USA

In this paper,the flocking flight of Northern Bald Ibises(Geronticus eremita)and their induced drag during the flock are *** Bald Ibises are long-range migratory *** birds fly in an echelon and V-shaped formation,possibly to reduce their drag;therefore,as a result,they may save energy to fly *** aerodynamic drag forces of each individual bird and the flock are modeled *** analysis shows how,during flocking flight,the drag force reduces as the size of the flock ***,wingtip spacing effects on the total drag of the flock are *** fraction of drag reduction of individual ibises is also *** initial arrangement scenarios are considered for flocks of ibises of different sizes in this *** shuffling algorithms are applied for position switching and energy balancing of the ibises during their *** is suggested that ibises can save energy by means of different arrangements of flock members during long *** results indicate that how different sizes of the birds can manipulate their positions to fly further and save energy during migration.

关键词： Drag Echelon Energy Flock Ibises Wingtips spacing

Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： Qian Ma Peng Jin frank L.Lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA Research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA IEEE

In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is ***,an augmented system is constructed by the tracking error system and reference *** transformation aims to convert the tracking control prob-lem into a stabilization control ***,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty *** on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is ***,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal *** proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety *** performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

Model-based accuracy enhancements for guarded conductivity measurements:determination of effective electrode areas utilising numerical field simulation

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High Voltage 2018年第3期3卷 217-225页

作者： Claudius Freye frank Jenau Institute of High Voltage Engineering TU Dortmund University44227 DortmundGermany

Methods utilising current measurements for conductivity and permittivity determination require precise knowledge of the effective electrode area in order to obtain accurate *** to field distortions(*** by fringing)in guarded electrode setups,the effective electrode area differs significantly from the geometrical *** on guarded electrode setups for conductivity determination,a generic method based on numerical field simulation is presented allowing a convenient determination of the relevant effective electrode *** this purpose,a brief overview of yet existing normative guidelines and related research work is ***-of-the-art conductivity measurement setups are presented in order to identify parameters which affect the field distribution within the measurement *** description of the implemented method and its realisation in COMSOL multiphysics is followed by its validation using analytical fringing ***,presented method is used for the evaluation of fringing effects and additional field distortion caused by design aspects of the measurement cell itself and potential imbalances related to the measurement ***,dependencies on conductivity of the surrounding environment are *** model-based accuracy enhancements are calculated and are leading to a gain in precision for conductivity determination of up to 25%compared to yet existing approaches.

关键词： electrode conductivity determination

The Initial Tangent of the Femoral Arterial Pressure Increase Is an Estimate of Left Ventricular Contractility in Patients Undergoing Cardiacsurgery

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Open Journal of Anesthesiology 2014年第9期4卷 207-216页

作者： matthias Langin Christian Kowalski frank Christ Bernhard Zwissler Hille Kisch-Wedel Department of Anesthesiology Ludwig Maximilians UniversityMunichGermany

Purpose: Assessment of contractile function is a major challenge in patients with left ventricular dysfunction, especially during cardiac surgery. The initial tangent of the femoral arterial pressure increase (tanin) has recently been described to be an estimate of left ventricular (LV) contractility. To confirm these findings tanin was compared to various indices of LV performance in patients undergoing cardiac surgery. Methods: Data from 17 patients were evaluated retrospectively. Myocardial performance was estimated by the echocardiographic indices ejection fraction (EF), shortening fraction (FS), circumferential fiber shortening velocity (Vcf), the parameters of pulse contour analysis area under the curve (AUC) and tanin. Measurements were taken before and after cardiopulmonary bypass (CPB). Results: Tanin increased significantly (813 ± 216 mmHg/s vs. 1490 ± 450 mmHg/s, p < 0.05) after CPB, as well as Vcf (0.89 ± 0.14 circ/s vs. 1.47 ± 0.27 circ/s, p < 0.05) and EF (65% ± 7% vs. 74% ± 6%, p < 0.05). FS did not change (40.7% ± 7% vs. 46.5% ± 5%, p = 0.30). AUC significantly dropped after CPB (435 ± 54 mmHg*s vs. 263 ± 27 mmHg*s). Tanin and Vcf correlated strongly (r = 0.70, p < 0.001), while tanin showed only weak correlation with EF (r = 0.36, p = 0.037). There was no significant correlation with FS (r = 0.31, p = 0.079). Tanin and AUC correlated inversely (r = -0.62, p < 0.001). Conclusions: While showing little or no correlation with EF and FS respectively, tanin correlated well with the less preload-dependent parameter Vcf, thus suggesting that tanin may be used as an easily accessible estimate of LV contractility during cardiac surgery.

关键词： Arterial Pressure Wave Form Analysis Left Ventricular Contractility Cardiacsurgery

FerryBox: Using Automated Water Measurement Systems to Monitor Water Quality: Perspectives for the Yangtze River and Three Gorges Dam

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Journal of Earth Science 2010年第6期21卷 861-869页

作者： Carsten frank Friedhelm Schroeder Wilhelm Petersen Helmholtz-Zentrum Geesthacht GmbH Institute for Coastal Research

The building of the Three Gorges Dam （Hubei （湖北） Province, China） has transformed a region with an economy based on sustainable agriculture for millennia into an entirely different environment within an exceptionally short time. This disrupts the natural biogeochemieal cycles of carbon, nutrients, and metals and possibly will affect the whole catchment including downstream ecosystems, such as wetlands, estuaries, deltas, and adjacent sea areas. Starting from changes that have already been documented, this article concentrates on the possible use of a ＂FerryBox＂, which is an automated water quality measurement system on board a ship or on shore, to monitor the short and long term development of the quality of the river water in the backwater area and downstream of the dam. While there are already research programmes running to monitor the water quality of the river and the backwater area, these programs are limited to ship campaigns with sampling and laboratory analysis. The spatial and temporal resolution of such measurements is not sufficient for an overall assessment of the water quality and for prognoses in the context of anthropogenic and climate change. Therefore, a concept of applying regular automated observations by a FerryBox is presented. It is shown that such systems are very well suited to give feedback for the assessment of measures to improve the water quality.

关键词： Three Gorges Dam Yangtze River eutrophication FerryBox.