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Raman Optical Activity and Raman Spectra of Amphetamine Species--Quantum Chemical Model Calculations and Experiments

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American Journal of Analytical Chemistry 2012年第6期3卷 410-421页

作者： Rolf Willestofte Berg Irene Shim peter cyril white Salim Abdali Department of Chemistry Technical University of DenmarkLyngbyDenmark ReForensics LincolnUK Biophysical Chemistry Group Department of ChemistryH.C.Orsted Inst.University of CopenhagenCopenhagenDenmark

Theoretical calculations and preliminary measurements of vibrational Raman optical activity (ROA) spectra of different species of amphetamine (amphetamine and amphetamine-H+) are reported for the first time. The quantum chemical calculations were carried out as hybrid ab initio DFT-molecular orbital calculations by use of the Gaussian 03W program, based on complete geometry minimizations of the conformational energy of the S-(+)-amphetamine molecule, the S-(+)-amphetamine-H+ ion, and the R-(–)-amphetamine molecule. Following this, harmonic frequency calculations have been made, providing information about the cation vibrational bands, expected in salts of single anions (chlorides) as well as in salts of anions with internal bonds (sulfates, hydrogen phosphates, etc.). It shows that the kind of anion should be given better attention, as so far it has often not been the case, when the spectra are employed for identification purposes. The DFT calculations show that the most stable conformations are those allowing for close contact between the aromatic ring and the amine hydrogen atoms. The internal rotational barrier within the same amphetamine enantiomer has a considerable influence on the Raman and ROA spectra. As predicted the experimental ROA spectra were found to depend on the chirality. Two street samples, provided by the London Police, were also measured and compared to the calculated ROA spectra. The street samples were found to contain different enantiomers of the protonated amphetamine-H+ sulfate. According to the present study the AMPH+ ion in aqueous sulfate solution seems to adopt a conformation in which the phenyl and ammonium groups are in transpositions, similar to what has been found in the solid state.

关键词： Amphetamine Raman ROA DFT Molecular Orbital Drugs Forensic

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Stable diffusion gradients in microfluidic conduits bounded by fluid walls

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Microsystems & Nanoengineering 2024年第3期10卷 357-367页

作者： Federico Nebuloni cyril Deroy peter R.Cook Edmond J.Walsh Department of Engineering Science Osney Thermo-Fluids InstituteUniversity of OxfordOxford OX20ESUK Sir William Dunn School of Pathology University of OxfordOxford OX13REUK

Assays mimicking in vitro the concentration gradients triggering biological responses like those involved in fighting infections and blood clotting are essential for biomedical *** assays prove especially attractive as they allow precise control of gradient shape allied to a reduction in *** microfluidic devices are fabricated using solid plastics that prevent direct access to responding ***-walled microfluidics allows the manufacture of circuits on standard Petri dishes in seconds,coupled to simple operating methods;cell-culture medium sitting in a standard dish is confined to circuits by fluid walls made of an immiscible *** develop and experimentally validate an analytical model of diffusion between two or more aqueous streams flowing at different rates into a fluid-walled conduit with the cross-section of a circular *** solid walls,fluid walls morph during flows as pressures fall,with wall shape changing down the *** model is validated experimentally for Fourier numbers<0.1 using fluorescein diffusing between laminar *** enables a priori prediction of concentration gradients throughout a conduit,so allowing rapid circuit design as well as providing bioscientists with an accurate way of predicting local concentrations of bioactive molecules around responsive and nonresponsive cells.

关键词： walls diffusion attractive

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Raman Optical Activity and Raman Spectra of Amphetamine Species—Quantum Chemical Model Calculations and Experiments

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American Journal of Analytical Chemistry（美国分析化学） 2012年第6期

作者： Rolf Willestofte Berg Irene Shim peter cyril white Salim Abdali

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Adaptation in brain structure and respiratory and olfactory structures across environmental gradients in African and North American muroid rodents

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Integrative Zoology 2024年第1期19卷 165-181页

作者： peter J.TAYLOR Aluwani NENGOVHELA Christiane DENYS Graham R.SCOTT Catherine M.IVY Department of Zoology School of Natural and Mathematical SciencesUniversity of VendaThohoyandouSouth Africa Afromontane Unit Department of Zoology and EntomologyUniversity of the Free StatePhuthaditjhabaSouth Africa Department of Mammalogy National MuseumBloemfonteinSouth Africa Institut de Systématique EvolutionBiodiversité(ISYEB)Muséum National d’Histoire NaturelleCNRSSorbonne UniversitéEPHEUniversitéDes AntillesParisFrance Department of Biology McMaster UniversityHamiltonOntarioCanada Guglielmo and Shoemaker Labs Advanced Facility for Avian ResearchUniversity of Western OntarioLondonOntarioCanada

Morphometric studies of 3D micro CT-scanned images can provide insights into the evolution of the brain and sensory structures but such data are still scarce for the most diverse mammalian order of *** reviewed and new data,we tested for convergence to extreme aridity and high elevation in the sensory and brain morphology of rodents,from morphometric data from micro-CT X-ray scans of 174 crania of 16 species of three distantly re-lated African murid(soft-furred mice,Praomyini,laminate-toothed rats,Otomyini,and gerbils,Gerbillinae)clades and one North American cricetid(deer mice and white-footed mice,Peromyscus)*** studies demon-strated convergent evolution acting on the oval window area of the cochlea(enlarged in extremely arid-adapted species of Otomyini and Gerbillinae)and on endocranial volume(reduced in high elevation taxa of Otomyini and Peromyscus).However,contrary to our predictions,we did notfind evidence of convergence in brain struc-ture to aridity,or in the olfactory/respiratory system(turbinate bones)to high *** structure differed,particularly in the petrosal lobules of the cerebellum and the olfactory bulbs,between Otomyini and Gerbillinae,with extreme arid-adapted species in each clade being highly divergent(not convergent)from other species in the same *** observed greater“packing”of the maxillary turbinate bones,which have important respiratory functions,in Peromyscus mice from high and low elevations compared to the high-elevation African Praomyini,but more complex patterns within Peromyscus,probably related to trade-offs in respiratory physiology and heat exchange in the nasal epithelium associated with high-elevation adaptation.

关键词： 3D morphometrics Africa brain size North America Rodentia sensory evolution

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Consistency features and fuzzy-based segmentation for shadow and reflection detection in digital image forgery

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Science China(Information Sciences) 2017年第8期60卷 83-100页

作者： Rajan CRISTIN Velankanni cyril RAJ St.peter’s Institute of Higher Education and Research Dr.M.G.R Educational and Research Institute University

Advances in photo editing software have made it possible to generate visually convincing photographic forgeries which have been increased tremendously in recent years. In order to alleviate the problem of image forgery, a handful of techniques have been presented in the literature to detect forgery either in shadow or reflection. This paper aims to develop a technique to detect the image forgery either in shadow or reflection using features enabled neural network. The proposed technique of image forgery detection contains three important steps, like segmentation, feature extraction and detection. In segmentation, shadow points and reflection points are identified using map-based segmentation and FCM clustering. Then, feature points from the shadow points and reflective parts are extracted by considering texture consistency and strength consistency using LVP operator. The final step of forgery detection is performed using the feed forward neural network, where a new algorithm called ABCLM is developed for training of neural network weights. The performance is analyzed with four existing algorithms using measures such as accuracy and MSE. From the analysis, we understand that the proposed technique obtained the maximum accuracy of 80.49%.

关键词： image forensics forgery detection shadow reflection texture neural network

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3D palaeogeographic reconstructions of the Phanerozoic versus sea-level and Sr-ratio variations

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Journal of Palaeogeography 2015年第1期4卷 64-84页

作者： Christian Vérard cyril Hochard peter O.Baumgartner Gérard M.Stampfli Université de Lausanne (UNIL) Institut des Sciences de la Terre (ISTE)Geopolis Ch–1015 Lausanne Switzerland

A full global geodynamical model over 600 million years （Ma） has been de- veloped at the University of Lausanne during the past 20 years. We show herein how the 2D maps were converted into 3D （i.e., full hypsometry and bathymetry）, using a heuristic-based approach. Although the synthetic topography may be viewed as relatively crude, it has the advantage of being applicable anywhere on the globe and at any geological time. The model allows estimating the sea-level changes throughout the Phanerozoic, with the possibility, for the first time, to flood accordingly continental areas. One of the most striking results is the good correlation with ＂measured＂ sea-level changes, implying that long-term variations are predominantly tectonically-driven. Volumes of mountain relief are also estimated through time and compared with strontium isotopic ratio （Sr-ratio）, commonly thought to reflect mountain belt erosion. The tectonic impact upon the general Sr-retio trend is shown herein for the first time, although such influence was long been inferred.

关键词： palaeogeography reconstruction hypsometry bathymetry sea-level Sr-ratio tectonic-climate relationship

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Geodynamic evolution of the Earth over the Phanerozoic:Plate tectonic activity and palaeoclimatic indicators

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Journal of Palaeogeography 2015年第2期4卷 167-188页

作者： Christian Vérard cyril Hochard peter O.Baumgartner Gérard M.Stampfli Université de Lausanne (UNIL) Institut des Sciences de la Terre (ISTE)

During the last decades, numerous local reconstructions based on field geol- ogy were developed at the University of Lausanne （UNIL）. Team members of the UNIL partici- pated in the elaboration of a 600 Ma to present global plate tectonic model deeply rooted in geological data, controlled by geometric and kinematic constraints and coherent with forces acting at plate boundaries. In this paper, we compare values derived from the tectonic model （ages of oceanic floor, production and subduction rates, tectonic activity） with a combination of chemical proxies （namely CO2, 87Sr/86Sr, glaciation evidence, and sea-level variations） known to be strongly in- fluenced by tectonics. One of the outstanding results is the observation of an overall decreas- ing trend in the evolution of the global tectonic activity, mean oceanic ages and plate velocities over the whole Phanerozoic. We speculate that the decreasing trend reflects the global cooling of the Earth system. Additionally, the parallel between the tectonic activity and CO2 together with the extension of glaciations confirms the generally accepted idea of a primary control of CO2 on climate and highlights the link between plate tectonics and CO2 in a time scale greater than 107 yr. Last, the wide variations observed in the reconstructed sea-floor production rates are in contradiction with the steady-state model hypothesized by some.

关键词： geodynamic plate tectonics plate model Phanerozoic palaeoclimate CO2,strontium glaciation

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Textual Anticipation and the Putative Reader in Persuasive Discourse

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外国语 2021年第1期44卷 2-20页

作者： peter R.R.white University of New South Wales SydneyAustralia

The notion that’monologic’written texts construe for themselves a putative addressee(variously termed the’ideal’,’imagined’,’virtual’,’intended’,’model’or’mock’reader)has received a great deal of scholarly attention,initially by scholars of literary fiction and subsequently by discourse analysts more *** paper is concerned with putative-reader positioning in persuasive texts and with how,through observing the relationships of alignment and dis-alignment which the author enters into with this putative reader,it is possible to better understand the rhetorical workings of these *** specifically,it demonstrates how,through an analysis of which beliefs,expectations and attitudes the author projects onto this putative addressee it is possible to better understand how such a text may be persuasive,to more systematically describe the’compliant readings’associated with a text and to more thoroughly deal with’ideological’workings of persuasive texts as they naturalize particular value systems and world *** outlining and demonstrating an approach to analyses of putative-addressee positioning,the paper draws on prior work in literary criticism scholarship and in university composition *** primary focus,however,is on developing prior work on the putative addressee in the appraisal-framework literature,in particular work which has attended to the role of the resources of dialogistic positioning(ENGAGEMENT)in’writing the reader into the text’.

关键词： persona persuasion dialogism readership

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Prevalence and correlates of depressive symptoms in adult patients with pulmonary tuberculosis in the Southwest Region of Cameroon

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Infectious Diseases of Poverty 2016年第1期5卷 432-439页

作者： Jules Kehbila cyril Jabea Ekabe Leopold Ndemnge Aminde Jean Jacques NNoubiap peter Nde Fon Gottlieb Lobe Monekosso Department of Medicine Faculty of Health SciencesUniversity of BueaBueaCameroon Clinical Research Education Networking and ConsultancyBP 3480 DoualaCameroon School of Public Health Faculty of Medicine and Biomedical SciencesUniversity of QueenslandBrisbaneAustralia Department of Medicine Groote Schuur Hospital and University of Cape TownCape TownSouth Africa Medical Diagnostic Center YaoundéCameroon Department of Public Health and Hygiene Faculty of Health SciencesUniversity of BueaBueaCameroon Department of Medicine Faculty of Health SciencesUniversity of Buea and Global Health Dialogue FoundationBueaCameroon

Background:Tuberculosis(TB)remains a global health challenge and depression is a significant contributor to the global burden of *** evidence suggests that there is an association between depressive symptoms and TB,lower adherence to treatment,and increased morbidity and ***,there is paucity of data regarding these associations in *** study aimed to determine the prevalence and correlates of depression in adult patients with pulmonary TB(PTB)in the Southwest Region of ***:A hospital-based cross-sectional study involving 265 patients with PTB was conducted from 2nd January to 31st March 2015 in the Limbe Regional Hospital and the Kumba District *** was diagnosed using the standard nine-item Patient Health Questionnaire,and classified as none,mild or *** regressions were used to investigate correlates of depression in these ***:Of the 265 patients(mean age 36.9±10 years)studied,136(51.3%)were *** prevalence of depression was 61.1%(95%CI:55.1–66.8),with a significant proportion(36.6%)having mild *** logistic regression analysis showed that being female(aOR=3.0,95%CI(1.7–5.5),P0.05),being on retreatment for TB(aOR=11.2,95%CI:5.2–31.1,P<0.001),having discontinued treatment(aOR=8.2,95%CI:1.1–23.3,P<0.05)and having a HIV/TB co-infection(aOR=2.5,95%CI:1.2–6.5,P<0.001)were factors associated with having a higher chance of being ***:Our study suggests that there is a high prevalence of depression among PTB patients,with more than one in two patients *** care for TB patients involving mental health practitioners is highly encouraged,especially for high-risk groups.

关键词： Prevalence Correlates Depression Pulmonary tuberculosis Cameroon

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Terrain based co-operative UAV mapping of complex obstacles using 2-D splinegon

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International Journal of Intelligent Computing and Cybernetics 2012年第3期5卷 248-292页

作者： Samuel B.Lazarus Antonios Tsourdos Brian A.white peter Silson Al Savvaris Camille-Alain Rabbath Nicolas Lèchevin School of Engineering Cranfield UniversityCranfieldUK Autonomous Systems Group Defence Academy of the United KingdomCranfield UniversityShrivenhamUK Defence Research and Development Canada-Valcartier Quebec CityCanada Numerica Technologies Inc.ValcartierQuebec CityCanada

Purpose-This paper aims to describe a recently proposed algorithm in terrain-based cooperative UAV mapping of the unknown complex obstacle in a stationary environment where the complex obstacles are represented as curved in *** also aims to use an extended Kalman filter(EKF)to estimate the fused position of the UAVs and to apply the 2-D splinegon technique to build the map of the complex shaped *** path of the UAVs are dictated by the Dubins path planning *** focus is to achieve a guaranteed performance of sensor based mapping of the uncertain environments using multiple ***/methodology/approach–An extended Kalman filter is used to estimate the position of the UAVs,and the 2-D splinegon technique is used to build the map of the complex obstacle where the path of the UAVs are dictated by the Dubins path planning ***-The guaranteed performance is quantified by explicit bounds of the position estimate of the multiple UAVs for mapping of the complex obstacles using 2-D splinegon *** is a newly proposed algorithm,the most efficient and a robust way in terrain based mapping of the complex *** proposed method can provide mathematically provable and performance guarantees that are achievable in ***/value-The paper describes the main contribution in mapping the complex shaped curvilinear objects using the 2-D splinegon *** is a new approach where the fused EKF estimated positions are used with the limited number of sensors’measurements in building the map of the complex obstacles.

关键词： Multiple sensor fusion Data fusion EKF based navigation Multiple UAVs 2-D splinegon Robust UAV localization Complex obstacle mapping Sensor fusion Navigation

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