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Non-Invasive Pressure Support Ventilation in Major Lung Resection for High Risk Patients: Does It Matter?

Open Journal of Thoracic Surgery 2012年第3期2卷 63-71页

作者： Bernhard CDanner Wolfgang Koerber Alexander Emmert Ulrike Olgemoeller Hilmar Doerge Michael Quintel carl-pcriee Friedrich ASchoendube Department of Thoracic and Cardiovascular Surgery University Medical Centre GottingenGottingenGermany Department of Pneumology Respiratory Care and Sleep MedicineEvangelical Hospital WeendeGottingenGermany Department of Anaes-thesiology Emergency and Intensive CareUniversity Medical Centre GöttingenGottingenGermany.

Background and purpose: Patients with severely impaired pulmonary function have an increased operative risk for major lung resection. The clinical benefits of pre- and perioperative, non-invasive pressure support ventilation (NIPSV) have up to now not been extensively evaluated. Patients with severely reduced pulmonary function were investigated in this prospective and randomised single centre clinical trial. Methods: Standard pulmonary evaluation was performed in all patients before major lung resection. To predict postoperative pulmonary function, a lung perfusion-ventilation scan was carried out. All patients enrolled in the study were instructed preoperatively on how to use a NIPSV respirator. Af-ter lung resection patients were randomised either for continuation of NIPSV or for standard treatment. Results: Of the 52 patients assessed, 21 patients met the inclusion criteria for the study protocol. Predicted mean postoperative FEV1 was 1.10 L (range 0.92 - 1.27 L). Lobectomy was performed in 14 patients, pneumonectomy in 6 patients and a segmentectomy in 1 patient. No inhospital deaths occurred. Pulmonary complications (reintubation, pneumonia) were more frequent in the NIPSV group than in the control group (3 patients versus 1 patient), without statistical significance (p = 0.31). Conclusions: We observed no mortality and a low morbidity in this high risk group. Postoperative continuation of NIPSV had no beneficial effect on the clinical outcome. Preoperative conditioning with NIPSV, however, seems to be a suitable tool for patients with severely impaired pulmonary function. This study may serve therefore as basis for further investigations for the potential clinical benefits of prophylactic NIPSV in major lung surgery.

关键词： Chronic Obstructive Lung Disease Clinical Trial Non-Invasive Positive-Pressure Ventilation Thoracic Surgery

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Situation analytics—at the dawn of a new software engineering paradigm

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Science China(Information Sciences) 2018年第5期61卷 5-18页

作者： carl K.CHANG Department of Computer Science Iowa State University

In this paper, I first review the seminal work by Thomas Kuhn — The Structure of Scientific Revolutions — and elaborate my view on paradigm shifts in software engineering research and practice as it turns 50 years old in 2018. I then examine major undertakings of the computing profession since early days of modern computing, especially those done by the software engineering community as a whole. I also enumerate anomalies and crises that occurred at various stages, and the attempts to provide solutions by the software engineering professionals in the past five decades. After providing such a background, I direct readers’ attention toward emerging anomalies in software engineering, at a severity level that is causing another software engineering crisis, and suggest a set of criteria for feasible solutions. The main theme of this paper is to advocate that situation analytics, equipped with necessary definitions of essential concepts including situation and intention as parts of a new computational framework, can serve as the foundation for a new software engineering paradigm named the Situation-Centric Paradigm. In this framework, situation is considered a new abstraction for computing and is clearly differentiated from the widely accepted existing abstractions, namely function and object. I argue that the software engineering professionals will inevitably move into this new paradigm, willingly or unwillingly, to empower Human-Embedded Computing(HEC) and End-User Embedded Computing(EUEC), much more than what they have done with traditional humancentered or user-centric computing altogether. In the end, I speculate that an ultimate agile method may be on the rise, and challenge readers to contemplate "what if" hundreds of thousands "end-user developers"emerge into the scene where the boundaries between end users and developers become much more blurred.

关键词： ultimate agile method context intention Internet of things paradigm situation software engineering human-embedded computing

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Diffusion in the Lorentz Gas

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Communications in Theoretical Physics 2014年第10期61卷 521-540页

作者： carl P.Dettmann School of Mathematics University of BristolBristol BS8 1TWUK

The Lorentz gas, a point particle making mirror-like reflections from an extended collection of scatterers,has been a useful model of deterministic diffusion and related statistical properties for over a century. This survey summarises recent results, including periodic and aperiodic models, finite and infinite horizon, external fields, smooth or polygonal obstacles, and in the Boltzmann–Grad limit. New results are given for several moving particles and for obstacles with flat points. Finally, a variety of applications are presented.

关键词： Lorentz gas Ehrenfest wind-tree model conductivity diffusion Burnett coefficients

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Out-of-core clustering of volumetric datasets

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1134-1140页

作者： GRANBERG carl J. Department of Computing Curtin University of Technology Perth Australia

In this paper we present a novel method for dividing and clustering large volumetric scalar out-of-core datasets. This work is based on the Ordered Cluster Binary Tree (OCBT) structure created using a top-down or divisive clustering method. The OCBT structure allows fast and efficient sub volume queries to be made in combination with level of detail (LOD) queries of the tree. The initial partitioning of the large out-of-core dataset is done by using non-axis aligned planes calculated using Principal Component Analysis (PCA). A hybrid OCBT structure is also proposed where an in-core cluster binary tree is combined with a large out-of-core file.

关键词： Out-of-core clustering Hybrid rendering Scientific visualization

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Scaling granular material with polygonal particles in discrete element modeling

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Particuology 2023年第4期75卷 151-164页

作者： Alireza Ahmadi Stefan Larsson carl Wersall KTH Royal Institute of Technology Division of Soil and Rock MechanicsBrinellvagen 2310044StockholmSweden

Despite advancements in computational resources,the discrete element method(DEM)still requires considerable computational time to solve detailed problems,especially when it comes to the large-scale *** addition to the geometry scale of the problem,the particle shape has a dramatic effect on the computational cost of ***,many studies have been performed with simplified spherical particles or *** scaling is an approach to increase the particle size to reduce the number of particles in the *** several particle scaling methods have been introduced,there are still some disagreements regarding their applicability to certain aspects of *** this study,the effect of particle scalping on the shear behavior of granular material is *** granular particles were scanned and imported as polygonal particles in the direct shear *** effect of particle size distri-bution,particle angularity,and the amount of scalping were *** results show that particle scalping can simulate the correct shear behavior of the model with significant improvement in computational ***,the accuracy of the scalping method depends on the particle angularity and particle size range.

关键词： Particle scaling Direct shear test Discrete element method PFC Polygonal shape Granular material

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Improved dynamic testing by impedance control

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Earthquake Engineering and Engineering Vibration 2011年第3期10卷 423-435页

作者： Jochen carl Mettupalayam V. Sivaselvan Department of Civil Environmental and Architectural EngineeringUniversity of Colorado at Boulder

In this paper, the issue of actuator-structure interaction in dynamic testing of structures is considered. The problem is approached from the novel standpoint of impedance control. It is shown that an effective strategy to design controls for dynamic testing is by designing the test system impedance. It is also shown that this can be achieved using feedforward compensation. The analysis is carried out in the context of displacement controlled dynamic testing, when the tested structure has a high and nonlinear stiffness. It is demonstrated that stable and accurate dynamic testing can be achieved using the proposed strategy, when this is not possible using traditional feedback control techniques. Furthermore, the impedance control and feedforward strategies are applied in the context of hybrid simulation, a technique of coupling computational and physical substructures applied in earthquake engineering. Here, a delay compensation scheme is necessary in addition to feedforward. Experimental results are presented that demonstrate both improved dynamic testing performance when impedance control is employed, and its applicability in hybrid simulation.

关键词： dynamic test actuator-structure interaction impedance control hybrid simulation feedforward strategy

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Impact of weather conditions and building design on contaminant infiltration from crawl spaces in Swedish schools-Numerical modeling using Monte carlo method

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Building Simulation 2022年第5期15卷 845-858页

作者： Fredrik Domhagen Paula Wahlgren carl-Eric Hagentoft Department for Architecture and Civil Engineering Division of Building TechnologyChalmers University of TechnologySE-41296GothenburgSweden

Some Swedish school buildings built in the 1960s and 1970s experience indoor air quality problems,where the contaminants are suspected to come from the crawl space underneath the *** poor indoor air quality causes discomfort among pupils and *** an exhaust fan to maintain a negative pressure difference in the crawl space relative to indoors or increasing the ventilation in the classroom are two examples of common measures taken to improve the indoor air ***,these measures are not always effective,and sometimes the school building has to be *** relation between pressure distribution,contaminant concentration in the classroom,outdoor temperature,wind,mechanical ventilation,and air leakage distribution is complex.A better understanding of these relations is crucial for making decisions on the most efficient measure to improve the indoor air *** this paper,a model for contaminant infiltration from the crawl space is used together with the Monte carlo method to study these *** are performed for several cases where different building shapes,building orientations,shielding conditions,and geographical locations are *** show,for example,that for a building with an imbalanced ventilation system,air is leaking from the crawl space to the classroom for the majority of cases and that concentration levels in the classroom are usually the highest during mild and calm days.

关键词： airtightness air permeability Monte carlo method infiltration model crawl space indoor air quality

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The Determinants of Plant Variety Protection Applications in China

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中国人口·资源与环境(英文版) 2007年第2期5卷 53-62页

作者： carl Pray Department of Agricultural Food and Resource Economics Rutgers University NJ 08901-8520 USA

China passed its Plant Variety Protection Act (PVPA) in 1997 which allowed us to do some initial testing of this proposition. We used a unique dataset on the applications of the new Plant Variety Protection (PVP), morphological characteristics, and institutional sources of all the important varieties of rice in three provinces of China to estimate the determinants of plant variety protection applications in China. The evidence suggests that both the government and private research programs are responding to economic and policy incentives and investing in plant variety protection as economists would expect profit maximizing firms to invest. The discussion of the evolution of the seed industry suggested that the combination of the new seed law in 2000 and the new plant variety protection regulation had changed the structure of the seed industry and provided an important incentive to invest in PVPs both by public research institutes and commercial firms. Finally, there is some preliminary evidence that private firms have smaller incentives to develop new varieties than to purchase the new varieties.

关键词： crop, variety, protection, application, China

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Pesticide food safety standards as companions to tolerances and maximum residue limits

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Journal of Integrative Agriculture 2015年第11期14卷 2358-2364页

作者： carl K Winter Elizabeth A Jara Department of Food Science and Technology University of California

Allowable levels for pesticide residues in foods, known as tolerances in the US and as maximum residue limits （MRLs） in much of the world, are widely yet inappropriately perceived as levels of safety concern. A novel approach to develop scientifically defensible levels of safety concern is presented and an example to determine acute and chronic pesticide food safety standard （PFSS） levels for the fungicide captan on strawberries is provided. Using this approach, the chronic PFSS level for captan on strawberries was determined to be 2 000 mg kg-1 and the acute PFSS level was determined to be 250 mg kg-1. Both levels are far above the existing tolerance and MRLs that commonly range from 3 to 20 mg kg-~, and provide evidence that captan residues detected at levels greater than the tolerance or MRLs are not of acute or chronic health concern even though they represent violative residues. The benefits of developing the PFSS approach to serve as a companion to existing tolerances/MRLs include a greater understanding concerning the health significance, if any, from exposure to violative pesticide residues. In addition, the PFSS approach can be universally applied to all potential pesticide residues on all food commodities, can be modified by specific jurisdictions to take into account differences in food consumption practices, and can help prioritize food residue monitoring by identifying the pesticide/commodity combinations of the greatest potential food safety concern and guiding development of field level analytical methods to detect pesticide residues on prioritized pesticide/commodity combinations.

关键词： pesticide residues food safety tolerances maximum residue limits (MRLs) regulation reference dose captan strawberries

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Enhanced aboveground biomass by increased precipitation in a central European grassland

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Ecological Processes 2018年第1期7卷 435-447页

作者： Md Lokman Hossain carl Beierkuhnlein Department of Geography Hong Kong Baptist University15 Baptist University RoadKowloon TongHong Kong Global Change Ecology International Elite Study ProgrammeFaculty of BiologyChemistry and Earth SciencesUniversity of BayreuthUniversitätsstraße 3095440 BayreuthGermany Department of Environmental Protection Technology German University BangladeshGazipur 1702Bangladesh Department of Biogeography University of BayreuthUniversitätsstraße 3095440 BayreuthGermany

Background:Global climate change is projected to increase temperature and alter precipitation pattern,which could affect grassland ***-term observation at a field experiment can be a powerful approach to explore the impacts of climate change on biomass productivity in *** attempting to understand how climatic variability regulates biomass productivity,we analyzed long-term records of temperature and precipitation to examine how variation of temperature and precipitation across 19 years affect biomass ***:We established the experiment with 64 plots in two blocks and planted 31 species in 30 different *** harvested aboveground biomass twice a year,sorted biomass by functional groups,and weighed dry *** site was mown after each *** did not apply any fertilizer and *** linear regression model,we examined the influences of growing season temperature and precipitation on biomass ***:The results showed that aboveground biomass productivity in September and annual were significantly increased in post-drought(2003–2015).The relationships of aboveground biomass productivity with growing season precipitation were significantly *** results showed that aboveground biomass productivity in June and annual were sensitive to growing season *** relationships of aboveground biomass productivity of the functional group of grasses with early growing season temperature were significantly *** growing season precipitation had a significant positive effect on aboveground biomass productivity of the functional groups of grasses and ***-drought aboveground biomass productivity of the functional groups of grasses in June and September were declined,whereas legumes significantly increased,which suggests that the role of dominant grasses may shift by legumes with global climate ***:Our results highlight that early and late growing temperature and precipitat

关键词： Aboveground biomass BIODEPTH experiment Climate change Functional groups Grassland biodiversity Hay meadow Precipitation variability Temperate grassland Temperature variability

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