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Analysis of spine loads in dentistry—impact of an altered sitting position of the dentist

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Journal of Biomedical Science and Engineering 2010年第7期3卷 664-671页

作者： max Wunderlich Thomas Eger Thomas Rüther Andreas meyer-Falcke Dieter Leyk 不详

Neck and low back pain causes highest disability rates in industrialized countries. Apart from blue-collar occupations dentists and dental care personnel are also strongly affected by work related back pain. However, due to missing analysing systems spine exposure could not be adequately estimated for sitting and non load bearing tasks. Therefore, a new biomechanical measurement system was developed to analyze spine and trunk kinematics. To explore the potential kinematics impact on the spine two days of periodontology care have been examined. Moreover, to asses the influence of an altered sitting position data was collected in 9 (day 1) and 12 (day 2) o’clock position. Data were collected and analyzed by the new 3D-SpineMoveGuard. The systems analyze postures and movements of spine and trunk by ultrasound and inclinometer. Two days of routine non-surgical periodontal treatment were recorded by a frequency of 10 Hz. Moderate awkward postures could be assessed for 90% of the treatment. Up to 85% of the working days were spent in isometric position. Movements were rare and of small amplitude. There were no relevant differences between 9 and 12 o’clock position. The frequently reported back pain in dentists is not only related to severe body postures rather than to the high amount of isometric spine loads. Moreover, an altered sitting position did not reduce this physiological stress. Therefore, dentist specific interventions concepts should pay more attention to physical training during and off work. Ergonomic investments should be carefully evaluated before implemented.

关键词： Occupational Medicine Periodontal Treatment Back Pain Ergonomics 3D-SpineMoveGuard

In-situ diagnostic of femtosecond laser probe pulses for high resolution ultrafast imaging

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Light(Science & Applications) 2021年第7期10卷 1326-1338页

作者： Chen Xie Remi meyer Luc Froehly Remo Giust Francois Courvoisier Ultrafast Laser Laboratory Key Laboratory of Opto-electronic Information Technology of Ministry of EducationSchool of Precision Instruments and Opto-electronics EngineeringTianjin University300072 TianjinChina FEMTO-ST Institute Univ.Bourgogne Franche-ComtéCNRS15B avenue des Montboucons25030 Besançon CedexFrance

Ultrafast imaging is essential in physics and chemistry to investigate the femtosecond dynamics of nonuniform samples or of phenomena with strong spatial *** relies on observing the phenomena induced by an ultrashort laser pump pulse using an ultrashort probe pulse at a later *** years have seen the emergence of very successful ultrafast imaging techniques of single non-reproducible events with extremely high frame rate,based on wavelength or spatial frequency ***,further progress in ultrafast imaging towards high spatial resolution is hampered by the lack of characterization of weak probe *** pump–probe experiments realized within solids or liquids,because of the difference in group velocities between pump and probe,the determination of the absolute pump–probe delay depends on the sample *** addition,pulse-front tilt is a widespread issue,unacceptable for ultrafast imaging,but which is conventionally very difficult to evaluate for the low-intensity probe *** we show that a pump-induced micro-grating generated from the electronic Kerr effect provides a detailed in-situ characterization of a weak probe *** allows solving the two issues of absolute pump–probe delay determination and pulse-front tilt *** approach is valid whatever the transparent medium with nonnegligible Kerr index,whatever the probe pulse polarization and *** it is nondestructive and fast to perform,this in-situ probe diagnostic can be repeated to calibrate experimental conditions,particularly in the case where complex wavelength,spatial frequency or polarization encoding is *** anticipate that this technique will enable previously inaccessible spatiotemporal imaging in a number of fields of ultrafast science at the micro-and nanoscale.

关键词： pump polarization laser

New collision detection method for simulating virtual plant populations

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International Journal of Agricultural and Biological Engineering 2019年第6期12卷 156-161页

作者： Weilong Ding Zangxin Wan Yan Xu Nelson max College of Computer Science&Technology Zhejiang University of TechnologyHangzhou 310026China Department of Computer Science University of CaliforniaDavis95616USA

Detecting and resolving the collision of organs between different plants or the collision of different organs of a single plant are key issues in the realistic construction of a virtual plant population.A suitable collision detection scheme is necessary to prevent a reduction in realism caused by organ penetration.A mixed bounding volume tree construction scheme based on the growth characteristics of tomato plants is proposed in this paper,and the construction mode of the bounding at all levels is simplified by using a digital tomato *** a parallel GPU approach,we designed a tomato plant population collision detection program with CUDA *** proposed method reduces the total collision detection time by 92%-96%.

关键词： plant simulation collision detection bounding volume GPU processing

Heterosis in plants:Manifestation in early seed development and prediction approaches to assist hybrid breeding

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Chinese Science Bulletin 2009年第14期54卷 2363-2375页

作者： THIEMANN Alexander meyer Stephanie SCHOLTEN Stefan Developmental Biology and Biotechnology Biocenter Klein FlottbekUniversity HamburgOhnhorststraβe 1822609 HamburgGermany Developmental Biology and Biotechnology Biocenter Klein FlottbekUniversity HamburgOhnhorststraβe 18 22609 HamburgGermany

Heterosis, or hybrid vigour, describes the superior performance of heterozygous hybrid individuals compared with their homozygous parental inbred lines. Although heterosis has been intensively used in plant breeding, the molecular and genetic mechanism underlying the phenomenon remains largely unknown. During the last years numerous laboratories initiated genomic approaches with new, often genome wide tools toward the elucidation of the molecular basis of heterosis. Various studies described differences in genome organization and gene expression of hybrids and their parental inbred lines. In maize, a considerable loss of co-linearity at many loci between different inbred lines was observed. Expression profile comparisons between inbred lines and hybrids revealed complex transcriptional networks specific for different developmental stages and tissues mainly in maize (Zea mays), rice (Oryza sativa) and Arabidopsis (Arabidopsis thaliana). Allele-specific expression data resolved the relative parental contributions and allowed figuring out the regulatory basis for expression variation in hybrids. Integrating all these complex expression data might help to get an idea about the molecular basis of heterosis. Thereby molecular processes during early seed development shortly after fertilization might be of particular importance, because the allelic interplay has to be coordinated after the unification of two diverse genomes and these processes might contribute to establish the basis for future performance of the sporophyte. Besides these fundamental interests in the molecular basis and manifestation of hybrid vigour applied aspects of the phenomenon are of high importance to support plant breeding and agriculture. Prediction methods are of special interest to identify the most promising parental lines of hybrid varieties, greatly reducing the financial effort and increasing the efficiency to develop new hybrid cultivars. Until now, most prediction approaches were based on g

关键词：植物育种方法水稻基因表达

Effect of surface roughness on sliding friction of micron-sized glass beads

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Friction 2014年第3期2卷 255-263页

作者： Jan meyer Regina FUCHS Thorsten STAEDLER Xin JIANG Chair of Surface and Materials Technology University of Siegen57068 SiegenGermany

In order to understand the contact phenomena of micron‐sized particles,which have a tremendous impact on a variety of applications in industry and technology,direct access to the loads as well as the displacements accompanying such contacts are *** particle ensembles show a size variation ranging from the nanometer to the tenths of micron *** the contact behavior of particles featuring radii of several up to several tenths of microns is scarcely studied as these particles are typically too large for atomic force microscopy(AFM)based approaches and too small for conventional macroscopic testing *** this work a nanoindenter based approach is introduced to gain insight into the contact mechanics of micron‐sized glass beads sliding on rough silicon surfaces at various constant low normal *** results are analyzed by a simple modified Coulomb friction law,as well as Hertz,JKR,and DMT contact theory.

关键词： sliding friction roughness colloid probe technique particle technology nanoindentation

Development and validation of an LC-MS/MS method for tyrphostin A9

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Journal of Pharmaceutical Analysis 2019年第3期9卷 163-169页

作者： Lyndsey F.meyer Dhaval K.Shah Department of Pharmaceutical Sciences School of Pharmacy and Pharmaceutical SciencesThe State University of New York at Buffalo

Here we have presented a sensitive and selective LC-MS/MS method for the quantification of tyrphostin A9, which is a selective inhibitor for platelet derived growth factor receptor tyrosine kinase and has been investigated in vitro as a potent oxidative phosphorylation uncoupler. The murine analytical method was developed for three biological matrices: cell culture media, 3T3-L1 cell lysate, and murine plasma. For each matrix the limit of detection and the limit of quantification were found to be 0.5 ng/mL and 1.0 ng/ mL, respectively. The range of standard curve for each matrix was 1.0-100 ng/mL, linearity was >0.99, and the precision and accuracy were within 20%. 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoic acid was found to be the most suitable internal standard. The validated LC-MS/MS method was used to investigate stability and in vitro pharmacokinetics of tyrphostin A9. It was found that tyrphostin A9 is susceptible to hydrolysis, and the degradation product was identified as 3,5-di-tert-butyl-4- hydroxybenzaldehyde. Tyrphostin A9 was not stable in biological matrices, and the rate of its degradation in murine plasma was faster than that in cell culture media. In vitro pharmacokinetic studies revealed that tyrphostin A9 concentrations in the cell culture media declined in a bi-exponential manner and the concentrations inside the adipocytes remained constant, suggesting tyrphostin A9 has an intracellular binding site and is retained within the cell. The LC-MS/MS method presented here paves the way for further quantitative investigations involving tyrphostin A9.

关键词： Tyrphostin 9/ A9/AG-9/Malonoben/SF6847 LC-MS/MS Stability Pharmacokinetics Tyrosine kinase inhibitor

Abnormal zone above the liquidus of Pb-Sb alloys

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Chinese Science Bulletin 1996年第10期41卷 873-878页

作者：边秀房李辉张林马家骥 max Thompson Shandong University of Technology Jinan 250014 China

Two curves have been identified above the liquidus in a binary Pb-Sb alloy phase dia-gram. The curves were obtained from thermal differential analysis and electrical resistivityexperiments and corresponded to sudden changes in the thermal effect and electricalresistivity curves. The zone between the two curves is called abnormal zone. When themelt of Pb-Sb alloys was superheated into the range of temperatures in the abnormal zone,

关键词： liquid metals electrical resistivity thermal history.

The effects of Lippia javanica dietary inclusion on growth performance,carcass characteristics and fatty acid profiles of broiler chickens

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Animal Nutrition 2016年第3期2卷 160-167页

作者： David A.Mpofu Upenyu Marume Victor Mlambo arno Hugo Department of Animal Science Faculty of Agriculture Science and TechnologyNorth-West University Food Security and Safety Niche Area Faculty of Agriculture Science and TechnologyNorth-West University Department of Microbial Biochemical and Food BiotechnologyUniversity of Free State

This study was conducted to determine the effect of inclusion of fever tea(Lippia javanica) leaf meal in broiler diets on growth performance, carcass characteristics and fatty acid(FA) profiles over a 42-day feeding period. One hundred and eighty, one-day-old, broiler chicks were randomly allocated to the following four treatments: 1) negative control(commercial broiler diet only [Negcontrol]); 2) positive control(commercial broiler diet + prophylactic antibiotics [Poscontrol]); 3) commercial broiler diet without prophylactic antibiotics + 5 g of L. javanica per kg of feed(Ljav5) and 4) commercial broiler diet without prophylactic antibiotics + 12 g of L. javanica per kg of feed(Ljav12). Body weights(BW) and feed intake(FI) were recorded weekly and used to calculate feed conversion ratio(FCR) and average daily weight gain(ADG). At the end of the trial(day 42),all chickens were slaughtered at a local commercial abattoir for assessment of carcass characteristics and FA profiles of meat. The broilers fed L. javanica had significantly(P < 0.05) lower FI compared with the other two groups. However,the broilers in the Poscontrol and Ljav5 treatment groups had higher(P < 0.05) ADG, lower FCR and higher slaughter weights. L. javanica inclusion had no effect on the breast weight, thigh weight, carcass weight, and dressing percentage of the broilers. Most of the n-3 FA were not affected by diets except for the docosapentaenoic, which was found to be higher(P < 0.05) in the Ljav12 treatment group and the lowest in the Negcontrol. The broilers in the Negcontrol and Poscontrol groups had higher(P < 0.05) total saturated fatty acids(SFA). On the contrary, the L. javanica fed broilers had higher(P < 0.05) total polyunsaturated fatty acids(PUFA), total n-3 FA and PUFA:SFA ratio and also had significantly lower n-6:n-3 ratios compared with the other two treatment groups. No differences were observed with regards to total monounsaturated fatty acids(MUFA) and total n-6 FA. Overall, t

关键词： Fever tea Feed conversion ratio Average daily gain Carcass weight Fatty acids

Personalizing a Service Robot by Learning Human Habits from Behavioral Footprints

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Engineering 2015年第1期1卷 79-84页

作者： Kun Li max Q.-H.Meng California Institute of Technology The Chinese University of Hong Kong

For a domestic personal robot, personalized services are as important as predesigned tasks, because the robot needs to adjust the home state based on the operator's habits. An operator's habits are composed of cues, behaviors, and rewards. This article introduces behavioral footprints to describe the operator's behaviors in a house, and applies the inverse reinforcement learning technique to extract the operator's habits, represented by a reward function. We implemented the proposed approach with a mobile robot on indoor temperature adjustment, and compared this approach with a baseline method that recorded all the cues and behaviors of the operator. The result shows that the proposed approach allows the robot to reveal the operator's habits accurately and adjust the environment state accordingly.

关键词： personalized robot habit learning behavioralfootprints