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Статті в журналах з теми "Structure porale complexe"

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Efraimiadou, H., St Lozios, and N. Evelpidou. "The Morphotectonic units of Ikaria island – Contribution in the natural hazards research." Bulletin of the Geological Society of Greece 44 (February 1, 2017): 79. http://dx.doi.org/10.12681/bgsg.11438.

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Present morphological and tectonic image of Ikaria island is the complex result of both the tem-poral evolution of the island, as part of the geodynamical evolution of the Hellenic Arc, especially that of the last stages (from the upper Miocene and after), and the exogenous factors. Also human impact functions as an additional parameter for the formation of Ikaria geoenvironment.According to field data and their analysis, computing and estimation which took part with the use of modern technologies (use of GIS, analysis of geographical and descriptive databases) the mor-photectonic units of Ikaria Island were defined. The definition of the morphotectonic units was based on their special features and more precisely on the lithological differentiation (granite, metamorphic rocks and post alpine formations) as well as the complex ductile and brittle structures (large scale ductile shear-zones and brittle detachment faults, normal faults, strike-slip transfer faults and join sets) and the morphological features (slope distribution, asymmetry of the drainage system, planation surfaces, morphological discontinuities etc).The synthesis of the special features of each morphotectonic unit in combination with the human impact (fires, overgrazing etc), defines the kind, the intensity and the geographical localization of the natural hazards which occur in various sites of the island, such as landslides, erosion, floods, seismic activity, relief changes, coastline changes etc.
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Otsuka, Shotaro, Hirohide Takahashi, and Shige H. Yoshimura. "1P543 Single-molecule structural and functional analyses of nuclear pore complex(26. Single molecule biophysics,Poster Session,Abstract,Meeting Program of EABS & BSJ 2006)." Seibutsu Butsuri 46, supplement2 (2006): S282. http://dx.doi.org/10.2142/biophys.46.s282_3.

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Nurkhamidah, Siti, Ayu Cahyarani Heksa, Tri Widjaja, Hikmatun Ni'mah, and Endarto Wardhono. "ONE-STEP ETHANOL EXTRACTION FOR PRODUCING PURIFIED GLUCOMANNAN FLOUR FROM PORANG CHIPS (AMORPHOPHALLUS ONCOPHYLLUS)." ASEAN Engineering Journal 14, no. 3 (August 31, 2024): 169–74. http://dx.doi.org/10.11113/aej.v14.21391.

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Porang (Amorphophallus oncophyllus) is unable to be consumed directly due to high calcium oxalate content. Two methods commonly used to reduce calcium oxalate contents are a mechanical method by grinding and sieving and in chemical process by using sodium chloride immersion. Most studies focused on how to increase glucomannan content in porang flour. Glucomannan is a hydrocolloid complex sugar used as dietary fiber. It is utilized as a thickening agent, gel-forming agent, and applied in the food and pharmaceutical industries. In previous studies, purification of glucomannan has been done by milling fresh tuber and extraction with multilevel ethanol concentration. In this study, extraction with ethanol 50% and 70% have been done with a variation of extraction time: 15, 30, 45 and 60 minutes. For preparation, porang chips are ground and sieved into 40 mesh flour. After extraction, glucomannan flour was filtered and dried, then characterized. Glucomannan content, calcium oxalate content, moisture content, ash content, viscosity, morphology, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) analysis were conducted. The experiment results show that the longer duration of extraction significantly decreased calcium oxalate content. Moisture content ranged from 9.99 – 10.85%. Better ash content was obtained at 50% ethanol, which exhibited under 3% of all immersion duration. The morphology of purified glucomannan flour observed through Scanning Electron Microscopy (SEM) showed a small amount of calcium oxalate as indicated by a needle-like structure. Ethanol concentrations and extraction duration effects on the purity and characterization of glucomannan flour from porang chips have been discussed in detail in this study.
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Nilavan, Anitha, Little Arockiaraj, Anucia Arputha, Jeevitha Velankanni, Rajendran Jeyalakshmi, Arockiam Roslin, Pushpa Murugesh, et al. "Corrosion resistance of mild steel immersed in simulated concrete pore solution in the presence of sodium potassium tartrate." Zastita materijala 64, no. 2 (2023): 170–76. http://dx.doi.org/10.5937/zasmat2302170n.

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The corrosion resistance of mild steel in simulated concrete pore solution (SCPS) in the absence and presence of sodium potassium tartrate (SPT) has been investigated by polarization technique and AC impedance spectra. The present study leads to the following conclusions. Polarization study reveals that sodium potassium tartrate system functions as anodic type of inhibitor. AC impedance spectra reveal that a shielding film is formed on the metal surface. When mild steel is used as rebar, sodium potassium tartrate may be mixed with concrete. Thus the mild steel will be protected from corrosion. The protective film consists of ferrous tartrate complex formed on metal surface. In the presence of sodium potassium tartrate the linear polarisation resistance increases from 226 Ohmcm2 to 455 Ohmcm2 , corrosion current decreases from 1.901x10-4A/cm2 to1.096 x10-4A/cm2 , charge transfer resistance (Rt) increases from 49 Ohmcm2 to 77 Ohmcm2 , impedance increases from 1.807 to 2.084, phase angle increases from 33.92° to 35.31° and double layer capacitance (Cdl) value decreases from 1.040x10-7 F/cm2 to 0.662 x10-7 F/cm2 . Corrosion potential shifts from -973 mV/SCE to -867 mV/SCE .This confirms that the inhibitor system functions as anodic type of inhibitor controlling anodic reaction predominantly. This formulation may find application in concrete technology. This may be used in the construction of bridges and concrete structures
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Micsik, Tamás, Anna Jakab, Csaba Lehoczki, and Árpád V. Patai. "Traditional Serrated Adenoma of the Gallbladder, a Case Report." Pathology and Oncology Research 28 (February 4, 2022). http://dx.doi.org/10.3389/pore.2022.1610133.

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While overwhelming majority of laparoscopic cholecystectomy specimens performed for gallstones or cholecystitis show rather typical findings, sometimes polypoid structures are also removed. These can be related to cholesterolosis or conventional adenomas, but occasionally extraordinary findings do emerge. In our case, a 67-year old lady with typical complaints of cholecystitis underwent routine laparoscopic cholecystectomy. Preoperative ultrasound revealed a polypoid mass with inflammation and without suspicion for malignancy. Microscopic examination showed partly conventional, low-grade dysplastic crypts forming a villous and rather complex structure. Ectopic crypt foci, slit-like serration pattern and serrated dysplasia with eosinophylic cytoplasm and centrally located nuclei were seen throughout the lesion, thus a traditional serrated adenoma (TSA) of the gallbladder was diagnosed. TSA represents the rarest subtype of serrated lesions in the colon and extracolonic manifestations are sporadically reported. Until now only a single case of a serrated adenoma was reported from the gallbladder. Here we describe the detailed clinical, pathological and molecular findings of our case and discuss these in the light of current literature data regarding this field.
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Sztankovics, Dániel, Dorottya Moldvai, Gábor Petővári, Titanilla Dankó, Fatime Szalai, Risa Miyaura, Viktória Varga, et al. "mTOR hyperactivity and RICTOR amplification as targets for personalized treatments in malignancies." Pathology and Oncology Research 30 (March 7, 2024). http://dx.doi.org/10.3389/pore.2024.1611643.

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The increasing knowledge of molecular alterations in malignancies, including mutations and regulatory failures in the mTOR (mechanistic target of rapamycin) signaling pathway, highlights the importance of mTOR hyperactivity as a validated target in common and rare malignancies. This review summarises recent findings on the characterization and prognostic role of mTOR kinase complexes (mTORC1 and mTORC2) activity regarding differences in their function, structure, regulatory mechanisms, and inhibitor sensitivity. We have recently identified new tumor types with RICTOR (rapamycin-insensitive companion of mTOR) amplification and associated mTORC2 hyperactivity as useful potential targets for developing targeted therapies in lung cancer and other newly described malignancies. The activity of mTOR complexes is recommended to be assessed and considered in cancers before mTOR inhibitor therapy, as current first-generation mTOR inhibitors (rapamycin and analogs) can be ineffective in the presence of mTORC2 hyperactivity. We have introduced and proposed a marker panel to determine tissue characteristics of mTOR activity in biopsy specimens, patient materials, and cell lines. Ongoing phase trials of new inhibitors and combination therapies are promising in advanced-stage patients selected by genetic alterations, molecular markers, and/or protein expression changes in the mTOR signaling pathway. Hopefully, the summarized results, our findings, and the suggested characterization of mTOR activity will support therapeutic decisions.
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Mu, Wentao, Peng Su, and Shanglei Ning. "Case Report: Incidentally Discovered a Rare Cystic Lesion of Liver: Multicystic Biliary Hamartoma." Pathology and Oncology Research 27 (March 30, 2021). http://dx.doi.org/10.3389/pore.2021.628323.

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Multicystic biliary hamartoma (MCBH) is an extremely rare cystic lesion of the liver. A 37-year old male patient was admitted to our hospital for incidentally discovered hepatic cystic lesions on abdominal ultrasonography. Abdominal contrast-enhanced computed tomography (CT) showed a multilocular cystic lesion in the segment VI, with mild enhancement in the septae and peripheral wall within the lesion. Only alanine transaminase (ALT) and carbohydrate antigen 19–9 (CA19–9) increased slightly above normal value. Preoperative tests suggested possibility of a benign mucinous cystic neoplasm (MCN) or intraductal papillary neoplasm of the bile duct (IPNB). Laparoscopic complete resection of the lesion was performed. Histopathological examination showed numerous variably sized ductal structures surrounded by periductal glands and fibrous connective tissues containing small blood vessels and smooth muscle bundles. Immunohistochemical staining (IHC) revealed that dilated ducts were positive for cytokeratin CK19, characteristic for biliary tract. Histopathological findings confirmed diagnosis of multicystic biliary hamartoma (MCBH). No recurrence occurred during 6 months follow-up. In conclusion, MCBH should be differentiating from hepatic cystic lesion and could be resected laparoscopically safely.
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Hoberg, Eric, and Kaylen Marie Soudachanh. "Diversity of Tetrabothriidae (Eucestoda) among Holarctic Alcidae (Charadriiformes): Resolution of the Tetrabothrius jagerskioeldi Cryptic Species Complex— Cestodes of Alcinae—Provides Insights on the Dynamic Nature of Tapeworm and Marine Bird Faunas under the Stockholm Paradigm." MANTER: Journal of Parasite Biodiversity, 2021. http://dx.doi.org/10.32873/unl.dc.manter16.

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We begin resolution of the Tetrabothrius jagerskioeldi–species complex with descriptions of Tetrabothrius alcae n. sp. based on numerous specimens, primarily in murres (species of Uria), from the greater North Pacific basin and Tetrabothrius sinistralis n. sp. based on cestodes in guillemots (species of Cepphus) from the central Bering Sea and West Greenland. These tetrabothriids are characterized, among 44 species of Tetrabothrius in avian hosts, by attributes of the scolex, male and female organ systems, structure and dimensions of the vitelline gland, numbers of testes, configuration of the genital atrium, genital papillae and the male and female atrial canals, position of the genital ducts relative to the poral osmoregulatory canals, structure, dimensions and position of the vaginal seminal receptacle, and dimensions of the embryophore and oncosphere, in addition to a broader array of characters. Remarkably, T. alcae, T. sinistralis, and a cryptic complex had remained unrecognized for the past century, given that these species are unequivocally differentiated by multiple suites of unique structural attributes relative to T. jagerskioeldi. Alcids and cestodes of the T. jagerskioeldi–complex are restricted to cold marine systems of advection and upwelling along coastal margins adjacent to the continental shelf or are associated with archipelagos (especially the Aleutian Arc), isolated islands and rocky headlands of the Bering Sea, Chukchi Sea, Gulf of Alaska, Sea of Okhotsk, and Sea of Japan. Tetrabothrius alcae, T. jagerskioeldi, and T. sinistralis may occur in sympatry but with minimal overlap in the faunas associated with murres (Alcini) and guillemots (Cepphini). Transmission for cestodes and persistence of this fauna is expected to be associated with pelagic and neritic systems adjacent to colony sites in zones where critical prey species are concentrated or secondarily dispersed downstream by predictable advective and upwelling processes and become available to foraging birds. Faunal assembly represents the outcomes of oscillating climate, shifting ranges (breakdown in isolation, ecological fitting, and exploration modes for cestodes) and the changing interfaces for resource availability maintained by trophic and habitat overlaps. Dynamics at these ecotones constitute the nexus of opportunity and capacity for infection by species of Tetrabothrius among avian hosts where capacity appears broad and opportunity is ecologically restricted in space and prevatime. Life history pathways for cestodes are tied to trophic associations and dynamics at mesoscales across marine domains and provinces. Resilience and connectivity through ecological fitting strongly suggest the influence of multiple trophic pathways for transmission and persistence of this complex fauna through differing assemblages of zooplankters, fishes, and cephalopods depending on locality, oceanographic conditions, and temporal variability. Changing conditions, especially ecological perturbations driven by climate oscillations, directly determine production cycles and distributions of micro- and macro-zooplankton, forage fishes, cephalopods, and trophic structure in high-latitude marine ecosystems. Expanding regimes of accelerating change emphasize the critical importance of field collections, archives, and baselines to assess biological outcomes across temporal and spatial scales. Parasite assemblages reveal macro- to meso-scale connectivity serving as adjuncts and proxies in recognizing and understanding outcomes for episodes of environmental oscillation and directional atmospheric and oceanic warming in marine ecosystems.
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Дисертації з теми "Structure porale complexe"

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Yacouba, Amani Abdoul Nasser. "Approche multi-géophysique pour la caractérisation de la fracturation et des propriétés de transport des roches carbonatées." Electronic Thesis or Diss., Orléans, 2024. http://www.theses.fr/2024ORLE1024.

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Dans un contexte de changements globaux et de transitions écologiques et énergétiques, le changement climatique induit une sècheresse récurrente et de crise de la ressource en eau dans plusieurs régions et continents. Il est donc crucial d'étudier les aquifères d'eaux douces afin d'accompagner ces transitions et assurer une gestion et une utilisation durable et raisonnée de cette ressource vitale. En l'occurrence, la zone vadose qui joue un rôle important dans la recharge de ces aquifères et le transfert d'éventuels polluants et d'intrants. La plupart du temps, cette zone non saturée en eau, se caractérise par la présence d'hétérogénéités (structure de pores, fractures, variation minéralogique) multi-échelles notamment lorsqu'il s'agit d'un milieu calcaire. Ces hétérogénéités sont complexifiées par les processus diagenétiques liés principalement à l'altération physico-chimique et minéralogique. La surimposition de ces phénomènes primaires et secondaires rend difficile l'estimation des propriétés pétrophysiques (porosité, perméabilité, saturation en eau) à partir des méthodes géophysiques. Parmi ces méthodes couramment utilisées, les méthodes acoustique et électrique sont bien adaptées car il existe, à priori, un lien étroit entre les hétérogénéités et les propriétés mesurées.Les travaux de recherche menés dans le cadre de cette thèse s'appuient ainsi sur une approche multi-géophysique permettant de mieux caractériser un réservoir carbonaté complexe en se basant notamment sur une analyse pétrophysique combinée à une description microstructurale fine.Dans ce travail, nous avons démontré l'influence de la microstructure sur la prédiction et la modélisation des propriétés pétroacoustiques ce qui conduit à une bonne discrimination de certains faciès, utile pour améliorer les modèles de simulation d'écoulements. De plus, ce travail a aussi permis de montrer la pertinence de la conductivité complexe dans la caractérisation des calcaires et la prédiction de leur perméabilité. Cependant, des développements supplémentaires sont nécessaires concernant la problématique du changement d'échelles des réservoirs complexes et hétérogènes
In a context of global changes and ecological and energy transitions, climate change induces recurrent drought and water resource crisis in several regions and continents. It is crucial to study groundwaters in order to support these transitions and ensure effective management and use of this vital resource. In particular, the vadose zone which plays an important role in the recharge of these groundwaters and the transfer of possible pollutants and inputs. Most of the time this unsaturated zone is characterized by multi-scale heterogeneities (e.g., pore structure, fractures, mineralogical variation) particularly in a limestone environment. These heterogeneities are complexified by diagenetic processes linked mainly to physicochemical and mineralogical alteration which leads to uncertainty in reservoir property (e.g., porosity, permeability, water saturation) estimation from geophysical methods. Among these methods, acoustic and electrical methods are well suited because of the strong relation between heterogeneities and the measured properties.This thesis relies on a multi-geophysical approach in order to better characterize a complex carbonate reservoir using petrophysical measurements combined with microstructural descriptions. Based on this approach, we demonstrated the influence of rock structure on the prediction and modeling of petroacoustic properties. This work leads to a good discrimination of some facies, which can be used to improve simulation and flow models. In addition, we demonstrate the relevance of complex conductivity measurements in limestone characterization and permeability prediction. However, additional developments are needed to understand the upscaling problematic for heterogeneous and complex reservoirs
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Bennett, Laura. "Community structure detection in complex biological networks." Thesis, King's College London (University of London), 2013. https://kclpure.kcl.ac.uk/portal/en/theses/community-structure-detection-in-complex-biological-networks(4a2e4275-b4c5-4598-85c3-cdfdbc213581).html.

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With the advent of high-throughput technology there has been a large increase in the availability of biological data, such as interaction data of genes, proteins and metabolites. It is therefore necessary to develop ways in which these data can be efficiently modelled and analysed. Networks over a natural modelling framework for complex biological systems and as such, network theory and related computational approaches have proven important in bioinformatics. A particular facet of network theory that has been employed to analyse biological networks is community structure detection. Community structure is a modular network topology where communities are defined as groups nodes with dense intra-community connections and less dense inter-community connections. Methods to uncover such communities in complex biological networks have the potential to contribute towards a better understanding of the underlying organisation of a system. Consequently, this thesis focuses on the development of a series of mathematical programming models to address various manifestations of the community structure detection problem. The aim is to produce more information-rich models that can accurately represent the features of biological systems; with weighted and unweighted interactions, disjoint and overlapping communities and network dynamics all being considered. First, the detection of disjoint communities in unweighted networks is approached through a two-stage procedure, known as iMod. A mixed integer nonlinear programming (MINLP) model optimises modularity to find an initial partition which is then improved by iteratively solving a mixed integer quadratic programming (MIQP) model. A comparative analysis shows that iMod finds globally optimal solutions for networks of up to 512 nodes and outperforms all other methods tested when applied to larger networks. Subsequently, the MINLP model is generalised to weighted networks, known accordingly as WeiMod. Competitive results are found when WeiMod is compared with several other well known methods from the literature. Next, the work on disjoint community structure is extended to _nd overlapping modules. An MINLP model, known as OverMod, transforms disjoint to overlapping communities through the optimisation of the community strength metric. OverMod is compared with similar methods from the literature and is further assessed on protein-protein interaction (PPI) networks to test the method's ability to extract meaningful biological results. It is shown that proteins assigned to more than one module exhibit topological and functional properties indicative of their strategically important role in the organisation of the PPI networks. The work on disjoint and overlapping community structure concludes with the investigation of a network generated from sequence, protein interaction and co-expression data, for the fungal pathogen, Fusarium graminearum. The functional coherence of communities, properties of multiclustered genes and aspects of virulence-associated genes are all explored in an attempt to link topological and functional features. Finally, the concept of community structure in dynamic networks is explored. Consensus clustering is tackled; de_ned as detecting a single partition of a dynamic network that is relevant across multiple snapshots. This is addressed by extending the previously proposed MIQP and MINLP models such that average modularity across network snapshots is now optimised. A comparison is made with a similar method from the literature showing that the proposed approaches achieve competitive results for small to medium sized networks. Overall, this thesis demonstrates that the exible nature of mathematical programming lends itself well to developing versatile solution procedures for community structure detection. The method evaluations show the proposed algorithms to be comparable to other approaches from the literature and able to detect meaningful results in biological applications. Finally, the methods described in this thesis have the potential to infer important topological-functional relationships and help to provide insight into the organisation and evolution of biological systems.
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Sivilich, Anjanette U. "Wheeler/Portage Nike missile launch site C-47 : historic structure report." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1175435.

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This is a historic structure report for the C-47 Nike missile launch site in Wheeler, Indiana. This report provides a description, condition assessment, and recommendation for restoration of the site since it has sustained damage from weather, fire, and vandals. The site is listed on the State Register and National Register of Historic Places and the Nike Preservation Group desires to turn the site into a Cold War museum and memorial.A history of the Cold War and development of the Nike missile systems and C-47 site provides the background of the project. Each structure and feature is described and the condition recorded. Recommendations for treatment and maintenance are provided. Suggestions are made for a phased restoration of the site to accommodate a Cold War museum. Since it is recommended the site be open to the public, issues regarding public health, safety, security, and handicap accessibility are addressed. This project does not provide a full management and preservation plan, measured HABS/HAER drawings, or a structural analysis.
Department of Architecture
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Willshaw, Stephen Kilgour. "On pattern-switching phenomena in complex elastic structures." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/on-patternswitching-phenomena-in-complex-elastic-structures(d013e89e-c413-4612-a1f7-9fc55739cdfb).html.

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We investigate global pattern-switching effects in 2D cellular solids in which the voids are arranged in a square lattice. Uniaxial compression of these structures triggers an elastic instability which brings about a period-doubling transformation of the void shapes at a critical strain. Specifically, a square array of circular voids forms a pattern of mutually orthogonal ellipses and a similar effect is observed for diamond-shaped voids. The onset of instability is governed by the void fraction and size-effects are found for the experimental samples. We establish empirical laws which characterise the stiffness, strength and stability of cellular structures comprising square arrays of circular voids. A comparison of these with predictions from a discrete model implies underestimation of the resistance of the lattice to buckling, although the size effects are replicated. We find similar pattern-switching effects in the cubic lattice, which is a three-dimensional porous cube. The effect of buckling in this system is to produce a 2D pattern in one plane of voids. In two-phase granular crystals, rearrangement of a square lattice of particles results in a new, period-doubled, structural pattern. This switch can occur via an intermediate phase depending on the size ratio of the particles as shown in experiments and numerical simulations.
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Longdon, Alexander. "Stably complex structures on self-intersection manifolds of immersions." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/stably-complex-structures-on-selfintersection-manifolds-of-immersions(7ed7cb10-a143-4638-8447-6f4353388565).html.

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In this thesis we study the problem of determining the possible cobordism types of r-fold self-intersection manifolds associated to self-transverse immersions f: M^{n-k} -> \R^n for certain values of n, k, and r. Namely, we study the double-point self-intersection manifolds of immersions M^{n+2} -> \R^{2n+2} and M^{n+4} -> \R^{2n+4}, focusing on the case when $n$ is even. In the case of self-transverse immersions f : M^{n+2} -> \R^{2n+2}, we see that when n is even the double-point self-intersection manifold is a boundary, which is a result originally due to Szucs. In the case of self-transverse immersions f : M^{n+4} -> \R^{2n+4}, we show than when n is even the double-point self-intersection manifold is either a boundary or cobordant to RP^2 x RP^2, which is a new result. We then show that for even n such that the binary expansion of n+4 contains 5 or more 1s, the double-point self-intersection manifold of a self-transverse immersion M^{n+4} -> \R^{2n+4} is necessarily a boundary. We also survey the case when n is odd. We also set up and study the complex versions of the above problems: self-transverse immersions f : M^{2k+2} -> \R^{4k+2} and f : M^{2k+4} -> \R^{4k+4} of stably complex manifolds with a given complex structure on the normal bundle of f$. In these cases, the double-point self-intersection manifold L associated to the immersion inherits a stably complex structure, and we attempt to determine which complex cobordism classes of stably complex manifolds may arise in this way. This is all new work. In the case of self-transverse complex immersions f : M^{2k+2} -> \R^{4k+2}, we show that the first normal Chern number of the double-point self-intersection manifold is a multiple of 2^{\lambda_{k+1}} for some integer \lambda_{k+1}, and provide upper and lower bounds for the value of \lambda_{k+1}. We also determine the exact value of \lambda_{k+1} in certain cases. In the case of self-transverse complex immersions f : M^{2k+4} -> \R^{4k+4}, we identify a large class of stably complex manifolds that may arise as the double-point self-intersection manifold of such an immersion and also identify a class of manifolds that may not. Additionally, in both cases we identify a necessary (and sometimes sufficient) condition for a stably complex manifold of the appropriate dimension to admit a complex immersion of the appropriate codimension.
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Hemming, Oliver. "Structure and reactivity of low-coordinate first-row transition metal complexes." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/structure-and-reactivity-of-lowcoordinate-firstrow-transition-metal-complexes(a7879b58-897e-4080-99f6-8551511a503a).html.

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Earth-abundant first-row transition metals have seen a renaissance in chemistry in recent years due to their relatively low toxicity and cost in comparison to precious metals. Furthermore open-shell transition metal complexes exhibit useful one-electron redox processes which contrasts to their heavier d block anologues. This thesis aims to synthesize and analyse the structure and reactivity of low-coordiante first-row transition metal complexes of from groups 7-9 with an aim to utilize these species in catalysis. The divalent compound [Co{N(SiMe3)2}2] reacts with the primary phosphines PhPH2 in the presence of an NHC ligand (IMe4) to yield the phosphinidene bridged dimer [(IMe4)2Co(µ-PMes)]2. The complex has interesting magnetic properties due to strong antiferromagnetic coupling between the two cobalt(II) centres. Increasing the steric bulk of the NHC yielded carbene-phosphinidene adducts (NHC·PAr). This transformation was shown to be catalytic. The structure and reactivity of complexes of the type [(NHC)xMn{(N(SiMe3)2}2] were investigated. The complexes exhibit similar structural properties to their iron and cobalt analogues; however their reactivity has been shown to differ. The addition of primary phosphines to complexes of the type [(NHC)xMn{N(SiMe3)2}2] yielded a range of manganese phosphide complexes. [Mn{N(SiMe3)2}2] also reacts with imidazolium salts at elevated temperatures to yield heteroleptic manganese NHC complexes. The reaction of [Mn{N(SiMe3)2}2] with IPr·HCl afforded the abnormal carbene complex [(aIPr)Mn{N(SiMe3)2}µ-Cl]2. A new monoanionic bidentate ligand is reported which has shown to be a useful ligand system to stabilize three-coordiante iron(II) complex. The reaction of [(L)Fe(Br)] with mesitylmagnesium Grignard or n-butyllithium yield the iron hydrocarbyls [(L)Fe(Mes)] and [(L)Fe(nBu)] with the latter being stable to β-hydrogen elimination. Finally [(L)Fe(nBu)] has been utilized as a pre-catalyst in the hydrophosphination of internal alkynes, showing selectivity for the E-isomeric vinylphosphine.
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Yuan, Daopeng. "Structural studies of human CD23 and its complexes." Thesis, King's College London (University of London), 2012. https://kclpure.kcl.ac.uk/portal/en/theses/structural-studies-of-human-cd23-and-its-complexes(b8946602-66b9-4b39-a02e-4cda67c1c26d).html.

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IgE plays a central role in the pathogenesis of immediate hypersensitivity reactions through interacting with its receptors, in particular the high affinity receptor FcεRI. The low-affinity IgE receptor, CD23, affects IgE-dependent immune responses by regulating the synthesis of IgE, facilitating allergen presentation to the immune system, and influencing the activation and differentiation of B- and T-cells. Surprisingly, CD23 is different from other Ig receptors and belongs to the C-type (calcium-dependent) lectin family. Calcium binding to CD23 affects IgE binding to CD23, but previous NMR and crystal structures of CD23 gave conflicting results concerning the calcium binding sites. Investigation of calcium binding site(s) in CD23 and its complexes may assist CD23- targeted drug design. DerCD23 (a fragment of human CD23 that consists of the lectin domain and part of the C-terminal tail) and derCD23 mutants designed to remove each of the two potential calcium binding sites, were expressed and purified. The crystal structures of Ca2+-bound wild type derCD23, the complex with the Fcε3-4 sub-fragment of IgE-Fc, and four putative calcium binding site mutants of derCD23 were solved. Binding affinities of derCD23 and its mutants for calcium and for IgE-Fc were measured with ITC and SPR. The results indicate a loop of derCD23 (loop 4) is stabilized upon calcium binding to “site 2” and thereby contributes to the increased binding affinity for IgE. In addition, a residue (D258) in the non-conserved “site 1” is observed to bind IgE directly in the Ca2+-bound derCD23/Fcε3-4 complex. Thus, Ca2+ bound to site 2 in CD23 stabilizes loop 4 for IgE binding, whereas site 1 has evolved to bind IgE directly. Clinical studies of IDEC152 (also known as Lumiliximab), a primatized IgG1, anti- CD23 monoclonal antibody (IDEC Pharmaceuticals, San Diego, CA) show positive clinical effects in patients with allergic asthma and chronic lymphocytic leukemia. The Fab fragment of IDEC152 was prepared by enzymatic digestion from IDEC152 and crystals of the complex of derCD23 with IDEC152-Fab were grown, which diffracted to 2.4 Å resolution.
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O'Brien, Kieran. "Electronic structure and bonding in pyrrolic macrocycle-supported complexes of actinides." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/electronic-structure-and-bonding-in-pyrrolic-macrocyclesupported-complexes-of-actinides(9c8ab96e-0e0d-4cca-aaa2-ef30102fbcc2).html.

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Chemistry of the early actinides has undergone a lot of developments in recent years, and due to the need of specialised laboratories to handle these often highly radioactive complexes, computational chemistry has become a powerful aid in understanding the physical properties of these unique systems. This thesis describes a systematic computational study of organoactinide and organometallic model complexes of the form [LAnX]n+ where L is the macrocyclic trans- calix[2]benzene[2]pyrrolide ligand using density functional theory (DFT) in conjunction with a variety of partition-based methods – Mulliken populations analysis (MPA), Hirshfield population analysis (HPA), natural population analysis (NPA) and the quantum theory of atoms in molecules (QTAIM) – with the aim of probing the electronic structure of the An-X and An-arene bonds as a function of the X ligand. Natural bond orbital (NBO) analysis was also used to study the nature of the An-X bonds, with these results compared to the QTAIM descriptions of covalency and ionicity in the [LAnX]n+ complexes. Analogous transition metal complexes of the form [LMX]n+ (M = Hf, W) have also been studied with the QTAIM and NBO approaches to compare with the actinide-based systems. Nucleus independent chemical shift (NICS) analysis was carried out to probe the extent of aromaticity of the arene rings of the L2- ligand in the closed-shell [LThX]+ complexes as a function of X ligand, and was compared with QTAIM measurements of aromaticity. The MPA also revealed Î ́-bonding to the arene rings of the L2- ligand and was compared to the NICS data. Bond energies and bond energy decomposition analysis (EDA) of An-X were further analysed and compared to the QTAIM data. These same analyses were carried out on complexes where the X-type ligand series was extended to include a larger set of first and second-row p-block based ligands. Finally, other, bi-metallic actinide-based complexes including the L2-/4- ligand were studied with the aim of understanding the thermal stabilities of these experimentally-characterised complexes, with analogous model complexes modelled to find potential synthetic targets. The Kohn-Sham molecular orbitals (KS-MOs) of some of these complexes were also analysed to try and find a rationale, based on their electronic structure, for the energetic preference for one binding mode of L-An over another.
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Alsayary, Omar. "Group 4 and Group 10 post metallocene ethylene polymerization catalysis : catalyst structure-polymer properties relationship." Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/group-4-and-group-10-post-metallocene-ethylene-polymerization-catalysis-catalyst-structurepolymer-properties-relationship(ae5d83a2-4e13-4b8c-b7cc-cf7d67667d3d).html.

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The new ligand L1 [2-[(E)-2,6-diisopropylphenyl-phenyimino]-2H-acenaphthylen-(1E)-ylidene]-(2,4,6-trimethyl-phenyl)-amine was prepared by stepwise addition of 2,6-diisopropylaniline and 2,4,6 trimethylaniline to acenaphthenequinone. The L1NiBr2 complex crystallized as a pseudo tetrahedral monomer, as determined by single crystal X-ray diffraction. This new catalyst L1NiBr2 and 3 related catalysts, bis(2,6-diisopropylphenyl)acenaphthenediimineNiBr2 (L2NiBr2), [(N,N'-bis-(2,6-diisopropylphenyl)-phenanthrene-9,10-diylidendiamineNi-η3-C3H4COOCH3)]+.{B[C6H3(CF3)2]4-} [(L3Ni-η3-C3H4COOCH3)]+.{B[C6H3(CF3)2]4-} and N-(2,6-diisopropylphenyl)-N'-(2,4,6-trimethylphenyl)-phenanthrene-9,10-diylidenediamineNiBr2 (L4NiBr2) were tested for activity in ethylene polymerization. The super-bulky α-diimine nickel catalysts [(η3- L3NiC3H4COOCH3)]+.{B[C6H3(CF3)2]4-} and L4NiBr2 successfully produced higher molecular weight polyethylene with a high level of linearity compared to the less bulky α-diimine nickel catalysts (L1NiBr2 and L2NiBr2). The super bulky α-diimine backbone helped to compress the reaction space and therefore impede the ethylene insertion to active centre of the catalyst. For this reason, the catalyst activity for super- bulky backbone ligands (L3 and L4) is lower than for their analogous less-bulky backbone ligands (L1 and L2). In general, for both backbones, the nickel catalysts with all-isopropyl substituents produced higher molecular weight polyethylene with less linearity compared to the nickel catalysts with methyl substituents. Moreover, for the acenaphthene backbone, the nickel catalysts with all isopropyl substituents (L2NiBr2) got a higher activity compared to the nickel catalysts with methyl substituents (L1NiBr2). A similar catalyst activity trend was not observed for phenanthrene backboned catalysts. In contrast, L4NiBr2 showed a higher activity compared to [(η3- L3NiC3H4COOCH3)]+.{B[C6H3(CF3)2]4-} For all catalysts, the majority of branches, as characterized by 13C nuclear magnetic resonance, were methyl branches. Polymers with a high level of branches showed a sharp intensity in the loss modulus measured by dynamic mechanical analysis due to a high level of interfacial chains. A reduction in catalyst activity was observed with all nickel catalysts when supported on silica. However, supporting nickel catalysts helps to improve the linearity of the polymer. The same ligands L3 and L4 were used with palladium and successfully produced two new catalysts [L3PdCH3NCCH3]+.{B[C6H3(CF3)2]4-} and [L4PdCH3NCCH3]+.{B[C6H3(CF3)2]4-. Catalyst [L3PdCH3NCCH3]+.{B[C6H3(CF3)2]4-} was more active and produced higher molecular weight and less branched polymer than catalyst [L4PdCH3NCCH3]+.{B[C6H3(CF3)2]4-} in the polymerization of ethylene.
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Solomon, Sophia Astero. "Allyl and pentadienyl carbanion complexes of alkali metals : metal- and functionality-directed structure and bonding." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/allyl-and-pentadienyl-carbanion-complexes-of-alkali-metals-metal-and-functionalitydirected-structure-and-bonding(a88c30ae-8e8c-49e5-86d7-cc95569aab72).html.

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Five ansa-tris(allyl) complexes [(PhSi{C3H3(SiMe3)}3)(Li?tmeda)3] (2.1), [(MeSi{C3H3(SiMe3)}3)(Li?pmdeta)3] (2.2), [(MeSi{C3H3(SiMe3)}3)-(Na.tmeda)3] (2.3), [(PhSi{C3H3(SiMe3)}3)(Na?tmeda)2Na]2 [2.4]2 and [(MeSi-{C3H3(SiMe3)}3)(K?OEt2)2(KLi{OtBu})]2 [2.5]2 have been synthesised, and studied by X-ray crystallography and NMR spectroscopy. A collaboration was undertaken to study some of the complexes by DFT. Crystallographic studies have shown that the overall structure of the complex is dependent on a combination of several factors: the metal cation; the substituent on the central silicon atom for the ansa-tris(allyl) ligands; and the co-ligand, tmeda or pmdeta. (tmeda = N,N,N?,N?¬-tetramethylethylenediamine and pmdeta = N,N,N?,N?,N??-pentamethyldiethylene-triamine). Solution studies of the ansa-tris(allyl) complexes showed that the solid-state structures are maintained in solution. The first examples of donor-functionalised allyl pro-ligands have been synthesised and coordinated to a variety of s-block metals; [Li{(SiMe3)2C3H2(1-CH2C4H7O)}]2 [4.1]2, [Li{(SiMe3)2C3H2(1-CH2CH2OCH3)}]2 [4.2]2, [(thf)K{(SiMe3)2C3H2(1-CH2C4H7O)}]2 [4.5]? and [Mg{(SiMe3)2C3H2(1-CH2C4H7O)}2] (4.6). As with the ansa-tris(allyl) complexes, both X-ray crystallographic and NMR spectroscopy studies have been undertaken, and the structures of the donor-functionalised allyl complexes were found to be dependent on the metal cation, with each cation coordinated in a different manner by the allyl ligand. For the potassium allyl complex 4.5 there is complete delocalisation of the allyl negative charge, and it is ?3-coordinated in a polymeric structure. However for lithium complexes, [4.1]2 and [4.2]2, the donor-functionalised allyl ligand is ?2-coordinated, and the negative charge is only partially delocalised. The magnesium complex 4.6 has the allyl ligand coordinated via a ?-bond to the metal and the allyl has localised single and double bonds.Finally, the synthesis of the first two donor-functionalised pentadienyl ligands and their lithium complexes are reported. Complexes [(tmeda)Li{1,5-(SiMe3)2C5H4(CH2C4H7O)}] (6.1) and [(tmeda)Li{1,5-(SiMe3)2C5H4(CH2CH2OCH3)}] (6.2) are the first structurally characterised lithium pentadienyl complexes, and are the first donor-functionalised pentadienyl complex of any metal. As well as structural characterisation, complexes 6.1 and 6.2 have been investigated by NMR spectroscopy and collaborative DFT studies. X-ray crystallography revealed that both complexes have the W-conformation of the pentadienyl ligand ?2-coordinated to the lithium cation, as well as the ether oxygen atom and the tmeda nitrogen atoms. DFT studies showed that the most stable gas-phase structure of the 1,5-bis(trimethylsilyl)-pentadienyl anion is the W-conformation, but its lithium complex is most stable in the U-conformation. The [Li{1,5-(SiMe3)2C5H4(CH2CH2OCH3)}]? anion has the W-conformation and the U-conformation is isoenergetic, but the addition of tmeda gives the W-conformation as the most stable in both the gas-phase and in toluene. Finally NMR spectroscopy studies showed that in solution complexes 6.1 and 6.2 are either in the symmetrical U-conformation or in fluxional process with a very low activation energy.
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Книги з теми "Structure porale complexe"

1

Euler, Ellen, and Paul Klimpel, eds. Föderale Vielfalt – Globale Vernetzung. Digitalisierung in den Ländern und der Welt. Hamburg University Press, 2016. http://dx.doi.org/10.15460/ddb.2.168.

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The contributions in the second volume of the series "Cultural Heritage in the Digital World" published by the German Digital Library show how in Germany, with its federal order, the mediation and ultimate networking of the cultural heritage is made via the Internet. The contributions provide information on the organizational structure and the infrastructure of digitization and on cooperation and political conditions. They show the political agenda in relation to the actual achievements. Teh status of the implementation is described. The articles provide information about digitization sites, projects and their coordination, describe institutional responsibilities, portals and cooperation with the German Digital Library, contain comments on long-term archiving. An outlook closes the considerations. Examples of concepts outside Germany complete the picture.
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Shaw, Pamela, and David Hilton-Jones. The lower cranial nerves and dysphagia. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780198569381.003.0429.

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Disorders affecting the lower cranial nerves – V (trigeminal), VII (facial), IX (glossopharyngeal), X (vagus), XI (accessory) and XII (hypoglossal) – are discussed in the first part of this chapter. The clinical neuroanatomy of each nerve is described in detail, as are disorders – often in the form of lesions – for each nerve.Trigeminal nerve function may be affected by supranuclear, nuclear, or peripheral lesions. Because of the wide anatomical distribution of the components of the trigeminal nerve, complete interruption of both the motor and sensory parts is rarely observed in practice. However, partial involvement of the trigeminal nerve, particularly the sensory component, is relatively common, the main symptoms being numbness and pain. Reactivation of herpes zoster in the trigeminal nerve (shingles) can cause pain and a rash. Trigeminal neuralgia and sensory neuropathy are also discussed.Other disorders of the lower cranial nerves include Bell’s palsy, hemifacial spasm and glossopharyngeal neuralgia. Cavernous sinus, Tolosa–Hunt syndrome, jugular foramen syndrome and polyneuritis cranialis are caused by the involvement of more than one lower cranial nerve.Difficulty in swallowing, or dysphagia, is a common neurological problem and the most important consequences include aspiration and malnutrition (Wiles 1991). The process of swallowing is a complex neuromuscular activity, which allows the safe transport of material from the mouth to the stomach for digestion, without compromising the airway. It involves the synergistic action of at least 32 pairs of muscles and depends on the integrity of sensory and motor pathways of several cranial nerves; V, VII, IX, X, and XII. In neurological practice dysphagia is most often seen in association with other, obvious, neurological problems. Apart from in oculopharyngeal muscular dystrophy, it is relatively rare as a sole presenting symptom although occasionally this is seen in motor neurone disease, myasthenia gravis, and inclusion body myositis. Conversely, in general medical practice, there are many mechanical or structural disorders which may have dysphagia as the presenting feature. In some of the disorders, notably motor neurone disease, both upper and lower motor neurone dysfunction may contribute to the dysphagia. Once dysphagia has been identified as a real or potential problem, the patient should undergo expert evaluation by a clinician and a speech therapist, prior to any attempt at feeding. Videofluoroscopy may be required. If there is any doubt it is best to achieve adequate nutrition through the use of a fine-bore nasogastric tube and to periodically reassess swallowing. Anticholinergic drugs may be helpful to reduce problems with excess saliva and drooling that occur in patients with neurological dysphagia, and a portable suction apparatus may be helpful. Difficulty in clearing secretions from the throat may be helped by the administration of a mucolytic agent such as carbocisteine or provision of a cough assist device.
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Частини книг з теми "Structure porale complexe"

1

Britell, Scott, Lois M. L. Delcambre, Lillian N. Cassel, Edward A. Fox, and Richard Furuta. "Enhancing Digital Libraries and Portals with Canonical Structures for Complex Objects." In Theory and Practice of Digital Libraries, 420–25. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-33290-6_46.

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Gimson, Alexander, and Simon M. Rushbrook. "Structure and function of the liver, biliary tract, and pancreas." In Oxford Textbook of Medicine, 2435–43. Oxford University Press, 2010. http://dx.doi.org/10.1093/med/9780199204854.003.1519.

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The liver, sited in the right upper quadrant of the abdomen, comprises eight segments, each of which is a complete functional unit with a single portal pedicle and a hepatic vein. Within the functional segments, the structural unit is the hepatic lobule, a polyhedron surrounded by four to six portal tracts containing hepatic arterial and portal venous branches from which blood perfuses through sinusoids, surrounded by walls of hepatocytes that are a single cell thick and lined by specialized endothelial cells with ‘windows’ (fenestrae), to the centrilobular region and the central hepatic veins. Bile secreted through the canalicular membrane of the hepatocyte collects in biliary canaliculi, from which it passes through the biliary tract into the gut....
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Letier, Pierre, and André Preumont. "Portable Haptic Arm Exoskeleton." In Prototyping of Robotic Systems, 122–45. IGI Global, 2012. http://dx.doi.org/10.4018/978-1-4666-0176-5.ch005.

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This chapter describes a seven degree of freedom force-reflective device able to produce haptic rendering on the human arm, either as master for teleoperation of a slave robot, or in interaction with a virtual reality. This project was conducted on behalf of the European Space Agency (ESA) as a prototype of the master device used for teleoperation of future anthropomorphic space robotic arms on the International Space Station (ISS). The motivation is to decrease the number of extravehicular activities of the astronauts, even for complex situations. The structure of portable anthropomorphic exoskeleton of 7 degrees of freedom has been selected by ESA because it allows a more intuitive control of anthropomorphic slave arms; it also allows multiple contact points, offers a larger workspace (comparable to the human arm). Besides, being attached on the astronaut, the system involves only internal forces (it is self-equilibrated) and can be used in zero-gravity.
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Gelson, William, and Alexander Gimson. "Structure and function of the liver, biliary tract, and pancreas." In Oxford Textbook of Medicine, edited by Jack Satsangi, 3032–42. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198746690.003.0315.

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The liver, sited in the right upper quadrant of the abdomen, comprises eight segments, each of which is a complete functional unit with a single portal pedicle and a hepatic vein. Within the functional segments, the structural unit is the hepatic lobule, a polyhedron surrounded by four to six portal tracts containing hepatic arterial and portal venous branches from which blood perfuses through sinusoids, surrounded by walls of hepatocytes that are a single cell thick and lined by specialized endothelial cells with ‘windows’ (fenestrae), to the centrilobular region and the central hepatic veins. Bile secreted through the canalicular membrane of the hepatocyte collects in biliary canaliculi, from which it passes through the biliary tract into the gut. The liver secretes bile, which aids digestion by emulsifying lipids, and has a central role in metabolism of (1) bilirubin, from haem; (2) bile salts, the principal mechanism for clearance of cholesterol; (3) carbohydrates; (4) amino acids and ammonia; (5) proteins, most circulating plasma proteins being produced by hepatocytes; and (6) lipid and lipoproteins. The pancreas lies in the retroperitoneum and is composed of (1) an exocrine portion centred on acini, producing an alkaline secretion containing digestive enzymes including serine proteases, exopeptidases, and lipolytic enzymes, draining through a ductal system into the duodenum; and (2) the islets of Langerhans, which secrete insulin (also glucagon, somatostatin, and pancreatic polypeptide).
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Baurley, James W., Arif Budiarto, Muhamad Fitra Kacamarga, and Bens Pardamean. "A Web Portal for Rice Crop Improvements." In Biotechnology, 344–60. IGI Global, 2019. http://dx.doi.org/10.4018/978-1-5225-8903-7.ch013.

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High quality models of factors influencing rice crop yield are needed in countries where rice is a staple food. These models can help select optimal rice varieties for expected field conditions. Development of a system to help scientist track and make decisions using this data is challenging. It involves incorporation of complex data structures - genomic, phenotypic, and remote sensing - with computationally intensive statistical modeling. In this article, the authors present a web portal designed to help researchers to manage and analyze their datasets, apply machine learning to detect how factors taken together influence crop production, and summarize the results to help scientists make decisions based on the learned models. The authors developed the system to be easily accessed by the entire team including rice scientist, genetics, and farmers. As such, they developed a system on a server architecture comprised of a SQLite database, a web interface developed in Python, the Celery job scheduler, and statistical computing in R.
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Grabowska, Marta. "Koncepcja jednolitego portalu e-Government dla obywatela w Polsce." In Obywatel w centrum działań e-administracji w Unii Europejskiej, 101–18. Ksiegarnia Akademicka Publishing, 2023. http://dx.doi.org/10.12797/9788381388894.06.

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Digitization of public administration is a process which serves not only to streamline functioning of public authorities but also to enable citizens an access to public information, to pursue their rights, to perform citizens’ duties and to enable them to take part in ruling in order to perform the idea of civil society. In the last few years the author of the paper conducted research within the class „Digital society and e-Government” run at the University of Warsaw, Poland on digitization of Polish public administration on the level of obliged entities, and on the attempt of Polish Authorities to create a unified portal (gateway) of e-Government for a citizen. It included also the European Union’s requirements and recommendations in this field. Although the Polish e-Government system presents a certain level of development however, it still is not complete and consistent, suffers luck of standardization, overlapping of available functions and modules and a unified gateway for a citizen. In the paper the concept of three parts of the e-Government system for a citizen in Poland is presented, i.e.: access to public information, public services for a citizen and participation in ruling, enriching the present concept with the third one. To carry out a research official documents of the EU and Poland on public administration and its digitization process were used, some elements of systems analysis were applied to investigate structures of public administration web pages and portals on both levels in Poland and the literature of the subject. The article presents the situation as at 31st August 2022.
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Liu, Jialin, Wenyi Xie, and Siru Liu. "Understanding Nursing Informatics: A Survey of Nurses’ Perception." In Studies in Health Technology and Informatics. IOS Press, 2024. http://dx.doi.org/10.3233/shti240249.

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This paper aims to explore nurses’ understanding of nursing informatics (NI). The structured and open-ended questionnaires were used to explore their knowledge of NI. Between 17 and 18 October 2023, the survey was conducted via a web portal and targeted 124 nurses attending in a nursing management training programme at the West China Hospital, Sichuan University. A total of 57.3% (71/124) of the nurses completed the survey. Of these, 29.6% (21/71) were unaware of NI and 70.4% (50/71) were aware of NI. However, only one of the nurses gave an accurate definition of NI. The results of this study suggest that there is a limited understanding of NI among senior nurses in mainland China, indicating a need to improve NI education for nurses.
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Nieto-Ortega, Sonia, Rebeca Lara, Giuseppe Foti, Ángela Melado-Herreros, and Idoia Olabarrieta. "Applications of Near-Infrared Spectroscopy (NIRS) in Fish Value Chain." In Infrared Spectroscopy - Perspectives and Applications [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.105736.

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Near-infrared spectroscopy (NIRS) has undergone a significant evolution in the last years due to the numerous scientific studies that revealed its potential for industrial applications, attracting a growing interest in the food sector. Furthermore, new advances have allowed the reduction in size and cost of the NIR devices, making them appropriate for on-site determinations. The complex structure of the fish value chain, combined to its high market value, makes this sector particularly vulnerable to fraud and adulteration practices. Also, the perishable nature of fish and fish products, as well as the lack of traceability, arises the urgent need for a fast, reliable and portable tool capable of precisely characterizing the quality and authenticity of the product while also ensuring its safety. In this chapter, the capabilities of NIRS combined to several chemometric techniques for quality, authenticity and safety applications are presented through an extensive review of the most recent research works.
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Nordin, Anis Nurashikin. "RF-MEMS Based Oscillators." In Advances in Wireless Technologies and Telecommunication, 120–55. IGI Global, 2012. http://dx.doi.org/10.4018/978-1-4666-0083-6.ch006.

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Today’s high-tech consumer market demand complex, portable personal wireless consumer devices that are low-cost and have small sizes. Creative methods of combining mature integrated circuit (IC) fabrication techniques with innovative radio-frequency micro-electro-mechanical systems (RF-MEMS) devices has given birth to wireless transceiver components, which operate at higher frequencies but are manufactured at the low-cost of standard ICs. Oscillators, RF bandpass filters, and low noise amplifiers are the most critical and important modules of any wireless transceiver. Their individual characteristics determine the overall performance of a transceiver. This chapter illustrates RF-oscillators that utilize MEMS devices such as resonators, varactors, and inductors for frequency generation. Emphasis will be given on state of the art RF-MEMS components such as film bulk acoustic wave, surface acoustic wave, flexural mode resonators, lateral and vertical varactors, and solenoid and planar inductors. The advantages and disadvantages of each device structure are described, with reference to the most recent work published in the field.
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Bindel, Michelle, Christiane Kreyer, and Elske Ammenwerth. "Extracting Evidence from Health IT Studies to Populate Logic Models." In Studies in Health Technology and Informatics. IOS Press, 2024. http://dx.doi.org/10.3233/shti240380.

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Background: Logic models graphically present the socio-technical components of a variety of ’programs’ such as educational programs. They show the underlying logic and assumptions of how a program is supposed to work. We suggest that they can be used to describe the mechanisms of complex socio-technical health IT interventions. Objective: To assess the suitability of logic models to describe cause-effect chains of health IT. Results: We are currently conducting an integrative review of the impact of patient portals on patient outcomes. We extracted the following elements of logic models from the found publications: resources, activities, output, outcome, and impact. These factors are then used to populate the logic model and form a structured graphical representation of the evidence. Until now, all the evidence we found could be fit into the logic model. The logic model was able to accommodate diverse types of evidence. Conclusion: Logic models seem to be suitable for representing evidence on the impact of health IT.
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Тези доповідей конференцій з теми "Structure porale complexe"

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Semenets, Valerii, Valeriia Chumak, Iryna Svyd, Oleg Zubkov, Oleksandr Vorgul, and Natalia Boiko. "DESIGNING THE STRUCTURE OF A GENERAL-PURPOSE TELEMEDICINE COMPLEX." In 2021 III International Scientific and Practical Conference Theoretical and Applied Aspects of Device Development on Microcontrollers and FPGAs. MC-ampFPGA-2021, 2021. http://dx.doi.org/10.35598/mcfpga.2021.016.

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Abstract Taking into account modern trends, the analysis of the construction principles of telemadic systems, networks and complexes is presented in the work. The general structure of providing telemedicine services is developed. Structures of realization of portable and mobile telemedicine complexes are offered. Infocommunication systems and networks for implementation in mobile telemedicine complexes are analyzed. The advantages of using the sensor mobile body area network of the IEEE 802.15.6 WBAN standard in mobile telemedicine complexes are justified. Keywords: telemedicine, telemedicine complex, medical services, device structure, microcontroller, sensor network, wireless sensor body area network.
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Lee, David E., and H. Thomas Hahn. "A Temporal Process Specification Language for Virtual Manufacturing Engineering." In ASME 1998 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/detc98/cie-5535.

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Abstract A process specification language is being developed for virtual manufacturing that provides a structured portable definition of a given manufacturing process as well as the ability to specify the temporal relationships between individual operation steps that compose a process. Based on the concepts embodied in markup languages such as HTML, SGML and XML, a portable process definition structure is defined. This structure provides a template from which virtual process specifications can be created. Subsequently, these structures can be exchanged between development environments for virtual process engineering and the actualized manufacturing facilities where processes are implemented. In addition, dependencies in time between the operation steps of a process such as common start times and operation serialization can be represented to allow for a complete specification of temporal behavior of a given manufacturing process. By providing this explicit mechanism for representing temporal constraints, a virtual manufacturing process can be viewed and utilized both in a localized application on a single virtual factory floor as well as distributed across multiple, interlinked virtual environments.
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Tiu, Johnny, and Richard Bachoo. "WAVE ANALYSIS OF A L-BEAM STRUCTURE WITH A BLOCKING MASS." In International Conference on Emerging Trends in Engineering & Technology (IConETech-2020). Faculty of Engineering, The University of the West Indies, St. Augustine, 2020. http://dx.doi.org/10.47412/ewgf2313.

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The wave vibration approach regards the vibrations present within a structure as waves, whereby each wave flows along a structural member and upon meeting a discontinuity; portions of the incident wave are reflected and transmitted across the discontinuity. The reflected, transmitted and propagating wave transformations are represented mathematically by matrices, which are used to develop a set of wave relation equations at each discontinuity that can be used to describe the frequency response of the system holistically. This method creates a systematic approach of analysing structures by utilizing common cases as building blocks for a specific structure. The L-joint, described as two beams meeting at right angles; is a ubiquitous case for spatial portal and structural frames, which may become geometrically complex. Such structures are well suited to a wave vibration approach due to the large number of geometric changes and the prevalence as well as recurrence of specific cases. In this paper, the L-joint expanded to include a blocking mass, typically employed in structural systems and allows for the isolation and reflection of vibration away from contiguous structural elements. Included are; variance of transmission and reflection matrix components as the size of the blocking mass increases, numerical examples and comparison to a Finite Element Model developed in ANSYS.
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Wei, Chuang, Bhushan Sonawane, Lei Cai, Shanfeng Wang, and Jingyan Dong. "Direct-Deposition and Multiple Materials Integration of Tissue Engineering Scaffolds." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-37922.

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High-aspect-ratio three-dimensional structures using biocompatible materials are critical for tissue engineering applications. This study develops a multi-nozzle direct-write approach to construct tissue engineering scaffolds with complex three-dimensional structures utilizing polymeric materials. This approach provides the capability to fabricate three dimensional scaffolds by depositing biocompatible UV-curable polymeric material and thermoplastic material (paraffin wax) layer-by-layer, which respectively are used as structural material and supporting material that will be removed later on. The designed structure is built by selectively extruding drops and/or filament through a set of syringes that host different functional materials, following a layer-by-layer sequence. The location of the deposition is precisely controlled by a high precision three-dimensional translational stage. After different structural/functional materials and the supporting material are deposited with predesigned pattern, the supporting material is removed by using appropriate chemical solvent which will not affect physical and chemical properties of the designed structure. The mechanical property of the structure, the equilibrium modulus and dynamic stiffness, can be engineered by designing different pore size for the scaffold. The multi-nozzle based direct writing approach provides a practical solution to build scaffolds for tissue engineering and integrate multiple functional materials together into a single scaffold structure.
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Alhadi, Almostafa, Zulkuf Azizoglu, and Zoya Heidari. "Assessment of Water Saturation in Carbonate Formations Honoring Complex Pore Structure: A New Insight Into Physics-Based Calibration." In 2022 SPWLA 63rd Annual Symposium. Society of Petrophysicists and Well Log Analysts, 2022. http://dx.doi.org/10.30632/spwla-2022-0027.

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The conventional rock physics models used for interpretation of resistivity measurements (e.g., Archie’s model) need to be calibrated using core measurements. This becomes challenging when core measurements are not available or significant vertical variation in rock types and pore structure is commonplace. Conventional models also assume homogeneous pore structure and uni-modal pore-size distribution. To overcome these challenges, we introduce a new workflow for water/hydrocarbon saturation assessment, in which model parameters are geometry related and can be estimated from analysis of the pore structure. Such workflow enables reliable interpretation of resistivity measurements in the presence of complex multi-modal pore structure. Furthermore, we investigate the consistency of the estimated model parameters (i.e., electrical constriction factor and tortuosity) in the pore-scale domain through the same rock types, for the purpose of developing a workflow for field applications. We first obtain high-resolution pore-scale computerized tomography (CT) images from rock samples in the same rock type and quantify pore-network characteristics (e.g., constriction factor, pore- and throat-size distributions) of the samples at different water saturation levels. Image analysis is used to obtain geometrical constriction factor. We obtain electrical resistivity of the samples through numerically solving Maxwell’s equations, which is used as an input in the introduced model. We successfully applied the introduced method to pore-scale images from three carbonate formations. We verified the consistency of the obtained parameters in the pore-scale domain by applying the method in other rock samples of the same rock type. Results demonstrated consistency in estimated electrical constriction factors and tortuosity values in each rock type. We observed variation of model parameters in different rock types. The introduced method successfully captured the variation of the pore structure within the formation and honored the geometrical heterogeneity of the complex carbonate rocks. Finally, we used the new workflow and Archie’s model to estimate water saturation. The new workflow enhanced water saturation estimates by 30% compared to Archie’s model with default parameters (i.e., a=1 and m=n=2). The outcomes of this paper can potentially minimize core-based calibration efforts for well-log-based water saturation assessment in rocks with complex pore structures such as carbonates. The introduced rock physics model captures the complexity of pore-network geometry and rock fabric and converged toward a more mechanistic model where most parameters have physical and geometrical meaning. The results are promising for enhanced assessment of water saturation in carbonate formations with minimal calibration efforts.
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Pidaparti, R. M., P. A. Sarma, A. S. C. Sinha, G. Vemuri, and A. M. Gacy. "Nuclear Membrane Dynamics of a Nuclear Pore Complex Structure." In ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/bed-23162.

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Abstract The nuclear pore complex (NPC) is an excellent example of a bio-molecular motor, since it operates primarily via energy dependent processes, and performs some of the most vital functions required for the survival of a cell. In the presence of appropriate chemical stimuli, the NPC apparently opens or closes, like a gating mechanism, and permits the flow of material in to and out of the nucleus. An NPC, with typical dimensions of 100–200 nm, is a megadalton (MDa) heteromultimeric protein complex, which spans the nuclear envelope and is postulated to possess a transporter-containing central cylindrical body embedded between cytoplasmic and nucleoplasmic rings as shown in Fig.1. A cell has many, presumably identical, NPCs, each of which participates in the import and export of nuclear material from within the nucleus [1–2]. Exactly how this transport occurs through the NPC is an open question, and a very important one, with profound implications for nanoscale devices for fluidic transport, genetic engineering and targeted drug delivery.
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Li, C. J., Y. He, and A. Ohmori. "Characterization of Structure of Thermally Sprayed Coating." In ITSC 1998, edited by Christian Coddet. ASM International, 1998. http://dx.doi.org/10.31399/asm.cp.itsc1998p0717.

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Abstract The structure of a thermally sprayed coating is generally of lamellar structure. There is generally porosity in the coating. The examination shows that the relationship between properties and porosity for conventionally processed porous materials is difficult to be applied to thermally sprayed coating because of complex pore networks. The lamellar structure of the coating and the bonding at the interfaces between lamellae often determine the properties of coating. It is generally difficult to evaluate quantitatively the structure of a thermally sprayed coating because of complicated pore networks in the coating. With the filling of the material different from the composition of the coating into the pores the structure of the coating including nonbonded interface area and also generally referred pores can be visualized. According to the distribution of filler in the coating the structure of a coating can be quantitatively evaluated using structural parameters such as lamellar thickness, lamellar bonding ratio, the width of interface gap and so on. The structural parameters necessary to describe the lamellar structure of thermal sprayed coatings and a method based on the pore filling and analysis of the distribution of filled materials are proposed.
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Kim, Yongwook, and Jarett Rooney. "Blast Mitigation Design for Urban Steel Structures Subjected to Close- in Detonations." In IABSE Congress, New York, New York 2019: The Evolving Metropolis. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2019. http://dx.doi.org/10.2749/newyork.2019.0448.

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<p>More frequent terrorist attacks to civilians, buildings, and infrastructures have been observed in recent years, which occasionally resulted in significant fatalities, financial damages, and service interruptions due to collapses of the structures. The collapse of a structure can be triggered by substantial or complete damages of essential structural members, potentially resulting from close-range detonations. Close-range detonations can be fatal even with a small portable charge weight. Many structures in major international cities are potentially exposed to close-range detonations, simply because there is no room to maintain a sufficient stand-off distance around each structural member. Current available approaches to blast resistant designs are focusing on far-range detonations; for close-range detonations, a non-linear explicit finite element analysis is required, instead. Most structural engineering firms do not have access to the analyses, because the details of the analysis are not readily available. In the present study, some details of the non-linear explicit finite element analysis are presented for close-range detonations. The same method is applied to numerical parametric studies for a standard steel column subjected to a range of charge weights and stand-off distances. In the study, the development of a performance-based engineering chart is discussed, which can be used by general structural engineers without performing the numerical analysis. A few practical strengthening layers of steel members are also investigated to effectively mitigate potential damages from close-range detonations.</p>
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Naveen, Paul, and Keka Ojha. "The Petrophysical Basis of Gas Transportation in Coal Reservoirs-Implications on Sorption and Diffusion." In SPE Conference at Oman Petroleum & Energy Show. SPE, 2022. http://dx.doi.org/10.2118/200116-ms.

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Abstract Comprehensive and systematic analysis of complex pore networks is vital in elucidating the transportation of gas in coal reservoirs. In this study, multiscale heterogeneity of high volatile bituminous (hvBb) coal was reconstructed to replicate the pore connectivity. Furthermore, LPA-N2 data provides information about pore characteristics. With the digital and physical data, reliable pore-scale modelling was developed for the prediction of pore filling, sorption and diffusion of gases, including the network of pores and flow paths. The results obtained from this systematic approach is informative and gives complete details about the internal structure of coal that is viable for transportation of gas. Pore-scale modelling replicates familiar lab results. Consequently, geoscientists and reservoir engineers will be able to shorten traditional cycle times dramatically, better understand increasingly complex heterogeneous coal reservoirs, and evaluate exploratory wells, asses field development potential, and investigate early production strategies, as well improved recovery scenarios.
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Britell, Scott, Lois Delcambre, Lillian Cassel, Edward Fox, and Richard Furuta. "Exploiting canonical structures to transmit complex objects from a digital library to a portal." In the 12th ACM/IEEE-CS joint conference. New York, New York, USA: ACM Press, 2012. http://dx.doi.org/10.1145/2232817.2232899.

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Звіти організацій з теми "Structure porale complexe"

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Snyder, Victor A., Dani Or, Amos Hadas, and S. Assouline. Characterization of Post-Tillage Soil Fragmentation and Rejoining Affecting Soil Pore Space Evolution and Transport Properties. United States Department of Agriculture, April 2002. http://dx.doi.org/10.32747/2002.7580670.bard.

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Tillage modifies soil structure, altering conditions for plant growth and transport processes through the soil. However, the resulting loose structure is unstable and susceptible to collapse due to aggregate fragmentation during wetting and drying cycles, and coalescense of moist aggregates by internal capillary forces and external compactive stresses. Presently, limited understanding of these complex processes often leads to consideration of the soil plow layer as a static porous medium. With the purpose of filling some of this knowledge gap, the objectives of this Project were to: 1) Identify and quantify the major factors causing breakdown of primary soil fragments produced by tillage into smaller secondary fragments; 2) Identify and quantify the. physical processes involved in the coalescence of primary and secondary fragments and surfaces of weakness; 3) Measure temporal changes in pore-size distributions and hydraulic properties of reconstructed aggregate beds as a function of specified initial conditions and wetting/drying events; and 4) Construct a process-based model of post-tillage changes in soil structural and hydraulic properties of the plow layer and validate it against field experiments. A dynamic theory of capillary-driven plastic deformation of adjoining aggregates was developed, where instantaneous rate of change in geometry of aggregates and inter-aggregate pores was related to current geometry of the solid-gas-liquid system and measured soil rheological functions. The theory and supporting data showed that consolidation of aggregate beds is largely an event-driven process, restricted to a fairly narrow range of soil water contents where capillary suction is great enough to generate coalescence but where soil mechanical strength is still low enough to allow plastic deforn1ation of aggregates. The theory was also used to explain effects of transient external loading on compaction of aggregate beds. A stochastic forInalism was developed for modeling soil pore space evolution, based on the Fokker Planck equation (FPE). Analytical solutions for the FPE were developed, with parameters which can be measured empirically or related to the mechanistic aggregate deformation model. Pre-existing results from field experiments were used to illustrate how the FPE formalism can be applied to field data. Fragmentation of soil clods after tillage was observed to be an event-driven (as opposed to continuous) process that occurred only during wetting, and only as clods approached the saturation point. The major mechanism of fragmentation of large aggregates seemed to be differential soil swelling behind the wetting front. Aggregate "explosion" due to air entrapment seemed limited to small aggregates wetted simultaneously over their entire surface. Breakdown of large aggregates from 11 clay soils during successive wetting and drying cycles produced fragment size distributions which differed primarily by a scale factor l (essentially equivalent to the Van Bavel mean weight diameter), so that evolution of fragment size distributions could be modeled in terms of changes in l. For a given number of wetting and drying cycles, l decreased systematically with increasing plasticity index. When air-dry soil clods were slightly weakened by a single wetting event, and then allowed to "age" for six weeks at constant high water content, drop-shatter resistance in aged relative to non-aged clods was found to increase in proportion to plasticity index. This seemed consistent with the rheological model, which predicts faster plastic coalescence around small voids and sharp cracks (with resulting soil strengthening) in soils with low resistance to plastic yield and flow. A new theory of crack growth in "idealized" elastoplastic materials was formulated, with potential application to soil fracture phenomena. The theory was preliminarily (and successfully) tested using carbon steel, a ductile material which closely approximates ideal elastoplastic behavior, and for which the necessary fracture data existed in the literature.
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Jauvin, Nathalie, François Aubry, Francis Ethridge, Isabelle Feillou, Éric Gagnon, Andrew Freeman, Nancy Côté, et al. Recherche-action visant le développement d’un modèle d’intervention préventive en SST par et pour les préposés aux bénéficiaires en CHSLD. IRSST, September 2024. http://dx.doi.org/10.70010/nkup8051.

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Contexte Ce rapport a pour objectif de présenter les résultats d’une recherche-action visant le développement d’un modèle d’intervention préventive en santé et sécurité du travail (SST) par et pour les préposés aux bénéficiaires (PAB) dans les centres d’hébergement et de soins de longue durée (CHSLD) du Québec. Les PAB sont au cœur des soins prodigués dans les milieux gériatriques. Malheureusement, l’augmentation du nombre de blessures et l’accentuation des problématiques de santé psychologique subies par ce personnel depuis quelques années fragilisent leur situation, ce qui se prouve en termes de faible rétention et de fort absentéisme chronique de ce personnel. Ce projet, qui est issu au départ d’une demande du milieu, visait à implanter une démarche d’intervention dans trois CHSLD du Québec, en nous inspirant d’autres études menées dans d’autres types d’organisation, comme les centres jeunesse. Revue de littérature La littérature scientifique nous enseigne que la participation des travailleurs au développement et à l’implantation de programme de prévention de la SST est une condition clé de leur succès, et ce préférablement à une intervention unilatéralement « classique » davantage axée uniquement sur la formation du personnel. Néanmoins, les CHSLD ne sont pas reconnus comme des milieux innovants, dans lesquels les PAB peuvent participer activement au développement des programmes de formation qui les concerne. La participation des PAB à une intervention préventive en SST, même si elle leur est destinée, apparaît comme un défi particulièrement important et difficile à relever. Objectifs L’objectif principal de cette recherche-action consistait à développer des modalités d’interventions préventives innovantes en matière de SST portées principalement par les PAB en CHSLD, afin d’en tirer des connaissances généralisables à d’autres milieux. Nos objectifs spécifiques visaient à : 1) cerner, dans les CHSLD, les facteurs de risque ainsi que les facteurs de protection présents ; 2) documenter et évaluer un processus mené « pour et par des PAB » qui vise à réduire les contraintes ciblées dans chaque milieu ; 3) documenter et évaluer le processus d’implantation de ces mesures ainsi que la participation des PAB dans la mise en place de la démarche ; 4) documenter les effets attendus des interventions proposées au sein des groupes de soutien à l’intervention (GSI) ; 5) dresser un inventaire des conditions (dimensions contextuelles et organisationnelles) favorables ou défavorables à l’implantation d’une intervention préventive misant sur la participation des préposés aux bénéficiaires. Cadre d’intervention L’étude a pris la forme d’une recherche-action. Selon cette approche, c’est principalement par l’action que l’on peut générer des connaissances scientifiques pour comprendre et changer la réalité sociale des individus et des systèmes, donc d’organisations telles que les CHSLD. Dans cette perspective, la théorie découle donc de l’action. Dans le cadre d’une recherche-action, on vise notamment à garantir que l’objet réponde à la fois aux problèmes pratiques des membres de l’organisation ainsi qu’aux préoccupations théoriques de recherche. Aussi, nous nous sommes appuyé sur le cadre proposé par Goldenhar et al., (2001) pour élaborer la démarche d’intervention. Il s’agit d’un modèle en 3 phases : le développement (l’identification a priori des risques ciblant des priorités sur lesquelles agir), l’implantation (l’implantation d’une intervention cohérente avec ces cibles via un GSI) et l’évaluation de l’intervention (l’étude de l’efficacité de l’intervention). Méthodologie Notre processus méthodologique a suivi le cadre d’intervention précité, soit trois phases de recherche-action : le diagnostic (phase I), l’intervention (phase II) et l’évaluation (phase III), et ce, dans trois CHSLD différents. Mentionnons que nous avons rajouté une phase d’entrevues, à la suite de la pandémie de la COVID-19 (phase I-B). Nous avons réalisé un total de 50 entrevues, soit 36 lors de la phase I (trois sites) et 21 en phase I-B. Nous avons réalisé également des heures d’intervention dans le cadre de la phase II, afin de développer les GSI. Lors des phases II et III, 15 informateurs clés ont été rencontrés sur une base individuelle et volontaire, et ce dans les deux CHSLD où ont été implantés des GSI. Notons que la pandémie a considérablement freiné notre projet et limité la portée de notre action. Il a été décidé, à la suite de la phase I-B, qu’un CHSLD serait supprimé de notre projet, tant les enjeux de recrutement pour les entrevues (phase I-B) et GSI (phase II) semblaient complexes. Résultats Les résultats de la phase I et I-B mettent de l’avant, dans les trois milieux, des facteurs de risque et des facteurs de protection relatifs à la charge de travail, au manque de soutien des collègues ou des supérieurs, à la faible reconnaissance et à la faible autonomie décisionnelle. Ce diagnostic a permis de préciser certaines pistes d’action pour les deux CHSLD participant à la phase II. Nous présentons ces pistes, de même que le processus complexe par lequel nous avons pu (ou non) développer des innovations organisationnelles dans les milieux. Dans le CHSLD du Hameau, quatre mesures ont été retenues (p. ex. : procéder à un exercice de clarification des rôles, des tâches partagées). Au CHSLD du Parvis, quatre mesures ont été aussi retenues (p. ex. élaborer un plan de contingence sur les unités). En guise d’évaluation, nous présentons plusieurs conditions gagnantes et défis identifiés par les acteurs des milieux interrogés. Discussion Notre projet a permis de documenter la complexité de développer des projets participatifs en CHSLD, notamment lorsqu’ils visent les PAB. Un premier facteur de complexité porte sur la structure hiérarchique même de l’organisation, qui donne peu de place et de pouvoir aux PAB, alors même que cette catégorie d’emploi est centrale en CHSLD. Un second facteur a trait à la fragilité importante de ces processus d’innovations lorsque des contraintes extérieures entravent ou bouleversent les pratiques quotidiennes. Certaines contraintes peuvent être importantes et de courte durée (comme la pandémie de la COVID-19), mais d’autres sont relativement récurrentes et fragilisent tout autant le même processus (manque de main-d’œuvre ponctuelle, épidémie d’influenza, visites de qualité, etc.). Des facteurs de soutien sont identifiés, comme l’engagement structuré de l’ensemble de l’organisation envers le projet (des hautes directions comme SAPA aux gestionnaires immédiats), la composition rigoureuse du comité chargé de développer et d’implanter les mesures proposées et le développement d’une perspective de pérennisation à moyen et long terme.
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Mazzoni, Silvia, Nicholas Gregor, Linda Al Atik, Yousef Bozorgnia, David Welch, and Gregory Deierlein. Probabilistic Seismic Hazard Analysis and Selecting and Scaling of Ground-Motion Records (PEER-CEA Project). Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, November 2020. http://dx.doi.org/10.55461/zjdn7385.

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This report is one of a series of reports documenting the methods and findings of a multi-year, multi-disciplinary project coordinated by the Pacific Earthquake Engineering Research Center (PEER) and funded by the California Earthquake Authority (CEA). The overall project is titled “Quantifying the Performance of Retrofit of Cripple Walls and Sill Anchorage in Single-Family Wood-Frame Buildings,” henceforth referred to as the “PEER–CEA Project.” The overall objective of the PEER–CEA Project is to provide scientifically based information (e.g., testing, analysis, and resulting loss models) that measure and assess the effectiveness of seismic retrofit to reduce the risk of damage and associated losses (repair costs) of wood-frame houses with cripple wall and sill anchorage deficiencies as well as retrofitted conditions that address those deficiencies. Tasks that support and inform the loss-modeling effort are: (1) collecting and summarizing existing information and results of previous research on the performance of wood-frame houses; (2) identifying construction features to characterize alternative variants of wood-frame houses; (3) characterizing earthquake hazard and ground motions at representative sites in California; (4) developing cyclic loading protocols and conducting laboratory tests of cripple wall panels, wood-frame wall subassemblies, and sill anchorages to measure and document their response (strength and stiffness) under cyclic loading; and (5) the computer modeling, simulations, and the development of loss models as informed by a workshop with claims adjustors. This report is a product of Working Group 3 (WG3), Task 3.1: Selecting and Scaling Ground-motion records. The objective of Task 3.1 is to provide suites of ground motions to be used by other working groups (WGs), especially Working Group 5: Analytical Modeling (WG5) for Simulation Studies. The ground motions used in the numerical simulations are intended to represent seismic hazard at the building site. The seismic hazard is dependent on the location of the site relative to seismic sources, the characteristics of the seismic sources in the region and the local soil conditions at the site. To achieve a proper representation of hazard across the State of California, ten sites were selected, and a site-specific probabilistic seismic hazard analysis (PSHA) was performed at each of these sites for both a soft soil (Vs30 = 270 m/sec) and a stiff soil (Vs30=760 m/sec). The PSHA used the UCERF3 seismic source model, which represents the latest seismic source model adopted by the USGS [2013] and NGA-West2 ground-motion models. The PSHA was carried out for structural periods ranging from 0.01 to 10 sec. At each site and soil class, the results from the PSHA—hazard curves, hazard deaggregation, and uniform-hazard spectra (UHS)—were extracted for a series of ten return periods, prescribed by WG5 and WG6, ranging from 15.5–2500 years. For each case (site, soil class, and return period), the UHS was used as the target spectrum for selection and modification of a suite of ground motions. Additionally, another set of target spectra based on “Conditional Spectra” (CS), which are more realistic than UHS, was developed [Baker and Lee 2018]. The Conditional Spectra are defined by the median (Conditional Mean Spectrum) and a period-dependent variance. A suite of at least 40 record pairs (horizontal) were selected and modified for each return period and target-spectrum type. Thus, for each ground-motion suite, 40 or more record pairs were selected using the deaggregation of the hazard, resulting in more than 200 record pairs per target-spectrum type at each site. The suites contained more than 40 records in case some were rejected by the modelers due to secondary characteristics; however, none were rejected, and the complete set was used. For the case of UHS as the target spectrum, the selected motions were modified (scaled) such that the average of the median spectrum (RotD50) [Boore 2010] of the ground-motion pairs follow the target spectrum closely within the period range of interest to the analysts. In communications with WG5 researchers, for ground-motion (time histories, or time series) selection and modification, a period range between 0.01–2.0 sec was selected for this specific application for the project. The duration metrics and pulse characteristics of the records were also used in the final selection of ground motions. The damping ratio for the PSHA and ground-motion target spectra was set to 5%, which is standard practice in engineering applications. For the cases where the CS was used as the target spectrum, the ground-motion suites were selected and scaled using a modified version of the conditional spectrum ground-motion selection tool (CS-GMS tool) developed by Baker and Lee [2018]. This tool selects and scales a suite of ground motions to meet both the median and the user-defined variability. This variability is defined by the relationship developed by Baker and Jayaram [2008]. The computation of CS requires a structural period for the conditional model. In collaboration with WG5 researchers, a conditioning period of 0.25 sec was selected as a representative of the fundamental mode of vibration of the buildings of interest in this study. Working Group 5 carried out a sensitivity analysis of using other conditioning periods, and the results and discussion of selection of conditioning period are reported in Section 4 of the WG5 PEER report entitled Technical Background Report for Structural Analysis and Performance Assessment. The WG3.1 report presents a summary of the selected sites, the seismic-source characterization model, and the ground-motion characterization model used in the PSHA, followed by selection and modification of suites of ground motions. The Record Sequence Number (RSN) and the associated scale factors are tabulated in the Appendices of this report, and the actual time-series files can be downloaded from the PEER Ground-motion database Portal (https://ngawest2.berkeley.edu/)(link is external).
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4

Dufour, Quentin, David Pontille, and Didier Torny. Contracter à l’heure de la publication en accès ouvert. Une analyse systématique des accords transformants. Ministère de l'enseignement supérieur et de la recherche, April 2021. http://dx.doi.org/10.52949/2.

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Анотація:
Cette étude porte sur une des innovations contemporaines liées à l’économie de la publication scientifique : les accords dits transformants, un objet relativement circonscrit au sein des relations entre consortiums de bibliothèques et éditeurs scientifiques, et temporellement situé entre 2015 et 2020. Ce type d’accords a pour objectif affiché d’organiser la transition du modèle traditionnel de l’abonnement à des revues (souvent proposées par regroupements thématiques ou collections) vers celui de l’accès ouvert en opérant une réaffectation des budgets qui y sont consacrés. Notre travail d’analyse sociologique constitue une première étude systématique de cet objet, fondée sur la recension de 197 accords. Le corpus ainsi constitué inclut des accords caractérisés par la coprésence d’une composante d’abonnement et d’une composante de publication en accès ouvert, même minimale (« jetons » de publication offerts, réduction sur les APC...). En conséquence, ont été exclus de l’analyse les accords portant uniquement sur du financement centralisé de publication en accès ouvert, que ce soit avec des éditeurs ne proposant que des revues avec paiement par l’auteur (PLOS, Frontiers, MDPI...) ou des éditeurs dont une partie du catalogue est constitué de revues en accès ouvert. L’accord le plus ancien de notre corpus a été signé en 2010, les plus récents en 2020 – les accords ne commençant qu’en 2021, même annoncés au cours de l’étude, n’ont pas été retenus. Plusieurs résultats se dégagent de notre analyse. Tout d’abord, on note une grande diversité des acteurs impliqués avec 22 pays et 39 éditeurs, même si certains consortiums (Pays-Bas, Suède, Autriche, Allemagne) et éditeurs (CUP, Elsevier, RSC, Springer) en ont signé beaucoup plus que d’autres. Ensuite, la durée des accords, comprise entre une et six années, révèle une distribution très inégalitaire, avec plus de la moitié des accords (103) signés pour 3 ans, ainsi qu’une faible proportion pour 4 ans ou plus (22 accords). Enfin, en dépit d’appels répétés à la transparence, moins de la moitié des accords (96) ont un texte accessible au moment de cette étude, sans qu’on puisse observer une tendance récente à une plus grande disponibilité. L’analyse montre également des degrés d’ouverture très variables, allant d’une simple information sur le répertoire ESAC en passant par la mise à disposition d’un format annotable jusqu’à l’attribution d’un DOI et d’une licence de réutilisation (CC-BY), en incluant le détail des sommes monétaires. Parmi les 96 accords disponibles, dont 47 signés en 2020, 62 ont fait l’objet d’une analyse en profondeur. C’est à notre connaissance la première analyse à cette échelle, sur un type de matériel non seulement inédit, mais qui était auparavant soumis à des clauses de confidentialité. Fondée sur une lecture minutieuse, l’étude décrit de manière fine leurs propriétés, depuis la matérialité du document jusqu’aux formules financières, en passant par leur morphologie et l’ensemble des droits et devoirs des parties. Les contenus des accords sont donc analysés comme une collection dont nous cherchons à déterminer les points communs et les variations, à travers des codages explicites sur certaines de leurs caractéristiques. L’étude pointe également des incertitudes, et notamment leur caractère « transitionnel », qui demeure fortement discuté. D’un point de vue morphologique, les accords montrent une grande diversité en matière de taille (de 7 à 488 pages) et de structure. Néanmoins, par définition, ils articulent tous deux objets essentiels : d’une part, les conditions de réalisation d’une lecture d’articles de revues, sous forme d’abonnement, mêlant des préoccupations d’accès et de sécurité ; d’autre part, les modalités de publication en accès ouvert, articulant la gestion d’un nouveau type de workflow à toute une série d’options possibles. Parmi ces options, mentionnons notamment le périmètre des revues considérées (hybrides et/ou accès ouvert), les licences disponibles, le degré d’obligation de cette publication, les auteurs éligibles ou le volume d’articles publiables. L’un des résultats les plus importants de cette analyse approfondie est la mise au jour d’un découplage presque complet, au sein même des accords, entre l’objet abonnement et l’objet publication. Bien entendu, l’abonnement est systématiquement configuré dans un monde fermé, soumis à paiement qui déclenche des séries d’identification des circulations légitimes tant du contenu informationnel que des usagers. Il insiste notamment sur les interdictions de réutilisation ou même de copie des articles scientifiques. À l’opposé, la publication en accès ouvert est attachée à un monde régi par l’accès gratuit au contenu, ce qui induit des préoccupations de gestion du workflow et des modalités d’accessibilité. De plus, les différents éléments constitutifs de ces objets contractuels ne sont pas couplés : d’un côté, les lecteurs sont constitués de l’ensemble des membres des institutions abonnées, de l’autre, seuls les auteurs correspondants (« corresponding authors ») sont concernés ; les listes de revues accessibles à la lecture et celles réservées à la publication en accès ouvert sont le plus souvent distinctes ; les workflows ont des objectifs et des organisations matérielles totalement différentes, etc. L’articulation entre les deux objets contractuels relève uniquement d’une formule de distribution financière qui, outre des combinaisons particulières entre l’un et l’autre, permet d’attribuer des étiquettes distinctes aux accords (offset agreement, publish & read, read & publish, read & free articles, read & discount). Au-delà de cette distribution, l’étude des arrangements financiers montre une gamme de dispositions allant d’une prévisibilité budgétaire totale, donc identique aux accords d’abonnement antérieurs, à une incertitude sur le volume de publication ou sur le montant définitif des sommes échangées. Les modalités concrètes de calcul des montants associés à la publication en accès ouvert sont relativement variées. S’il existe effectivement des formules récurrentes (volume d’articles multiplié par un prix individuel, reprise de la moyenne des sommes totales d’APC des années précédentes...), le calcul des sommes en jeu est toujours le résultat d’une négociation singulière entre un consortium et un éditeur scientifique, et aboutit parfois à des formules originales et complexes. À ce titre, l’espace des possibles en matière de formules financières n’est jamais totalement clos. Par ailleurs, la volonté des consortiums d’opérer une « transformation » de leurs accords vers la publication à coût constant renvoie à des définitions diversifiées du « coût » (inclusion ou non des dépenses d’APC préexistantes) et de la constance (admission ou pas d’une « inflation » à 2 ou 3%). De plus, nous n’avons observé aucune disposition contractuelle permettant d’anticiper les sommes en jeu au-delà de l’horizon temporel de l’accord courant. La grande diversité des accords provient d’une part des conditions initiales des relations entre consortiums et éditeurs scientifiques – les sommes dépensées en abonnement étant le point de départ des nouveaux accords –, d’autre part des objectifs de chaque partie. Même si cette étude excluait volontairement les négociations, les accords portent des traces de ces objectifs. Ainsi, de nombreux accords sont de nature explicitement expérimentale, quand certains visent un contrôle budgétaire strict, ou d’autres ambitionnent, dans la période plus récente, la publication du plus grand nombre possible d’articles en accès ouvert. C’est dans ce dernier cas qu’on touche à l’ambiguïté des attentes générales sur les accords transformants. En effet, pour les consortiums, la dimension « transformante » consiste essentiellement à transférer les sommes traditionnellement allouées à l’abonnement vers la publication en accès ouvert. Mais l’objectif n’est jamais de transformer le modèle économique des revues, c'est-à-dire de faire basculer des revues sous abonnement ou hybrides en revues entièrement en accès ouvert. D’ailleurs, aucune clause ne vise une telle fin – à l’exception du modèle d’accord proposé par l’éditeur ACM. Du côté des éditeurs, et notamment de Springer, le caractère cumulatif des accords nationaux passés vise à projeter un monde de la publication où l’accès ouvert devient de fait quantitativement très dominant, sans pour autant modifier de manière pérenne le modèle économique de leurs revues. Notre étude montre que les accords transformants actuels ne permettent pas d’assurer de manière durable une transition de l’économie de la publication vers l’accès ouvert, dans la mesure où ils n’offrent pas de garantie sur le contrôle des dépenses ni sur la pérennité de l’ouverture des contenus. L’avenir des relations entre consortium et éditeur demeure largement indéterminé.Cette étude porte sur une des innovations contemporaines liées à l’économie de la publication scientifique : les accords dits transformants, un objet relativement circonscrit au sein des relations entre consortiums de bibliothèques et éditeurs scientifiques, et temporellement situé entre 2015 et 2020. Ce type d’accords a pour objectif affiché d’organiser la transition du modèle traditionnel de l’abonnement à des revues (souvent proposées par regroupements thématiques ou collections) vers celui de l’accès ouvert en opérant une réaffectation des budgets qui y sont consacrés. Notre travail d’analyse sociologique constitue une première étude systématique de cet objet, fondée sur la recension de 197 accords. Le corpus ainsi constitué inclut des accords caractérisés par la coprésence d’une composante d’abonnement et d’une composante de publication en accès ouvert, même minimale (« jetons » de publication offerts, réduction sur les APC...). En conséquence, ont été exclus de l’analyse les accords portant uniquement sur du financement centralisé de publication en accès ouvert, que ce soit avec des éditeurs ne proposant que des revues avec paiement par l’auteur (PLOS, Frontiers, MDPI...) ou des éditeurs dont une partie du catalogue est constitué de revues en accès ouvert. L’accord le plus ancien de notre corpus a été signé en 2010, les plus récents en 2020 – les accords ne commençant qu’en 2021, même annoncés au cours de l’étude, n’ont pas été retenus. Plusieurs résultats se dégagent de notre analyse. Tout d’abord, on note une grande diversité des acteurs impliqués avec 22 pays et 39 éditeurs, même si certains consortiums (Pays-Bas, Suède, Autriche, Allemagne) et éditeurs (CUP, Elsevier, RSC, Springer) en ont signé beaucoup plus que d’autres. Ensuite, la durée des accords, comprise entre une et six années, révèle une distribution très inégalitaire, avec plus de la moitié des accords (103) signés pour 3 ans, ainsi qu’une faible proportion pour 4 ans ou plus (22 accords). Enfin, en dépit d’appels répétés à la transparence, moins de la moitié des accords (96) ont un texte accessible au moment de cette étude, sans qu’on puisse observer une tendance récente à une plus grande disponibilité. L’analyse montre également des degrés d’ouverture très variables, allant d’une simple information sur le répertoire ESAC en passant par la mise à disposition d’un format annotable jusqu’à l’attribution d’un DOI et d’une licence de réutilisation (CC-BY), en incluant le détail des sommes monétaires. Parmi les 96 accords disponibles, dont 47 signés en 2020, 62 ont fait l’objet d’une analyse en profondeur. C’est à notre connaissance la première analyse à cette échelle, sur un type de matériel non seulement inédit, mais qui était auparavant soumis à des clauses de confidentialité. Fondée sur une lecture minutieuse, l’étude décrit de manière fine leurs propriétés, depuis la matérialité du document jusqu’aux formules financières, en passant par leur morphologie et l’ensemble des droits et devoirs des parties. Les contenus des accords sont donc analysés comme une collection dont nous cherchons à déterminer les points communs et les variations, à travers des codages explicites sur certaines de leurs caractéristiques. L’étude pointe également des incertitudes, et notamment leur caractère « transitionnel », qui demeure fortement discuté. D’un point de vue morphologique, les accords montrent une grande diversité en matière de taille (de 7 à 488 pages) et de structure. Néanmoins, par définition, ils articulent tous deux objets essentiels : d’une part, les conditions de réalisation d’une lecture d’articles de revues, sous forme d’abonnement, mêlant des préoccupations d’accès et de sécurité ; d’autre part, les modalités de publication en accès ouvert, articulant la gestion d’un nouveau type de workflow à toute une série d’options possibles. Parmi ces options, mentionnons notamment le périmètre des revues considérées (hybrides et/ou accès ouvert), les licences disponibles, le degré d’obligation de cette publication, les auteurs éligibles ou le volume d’articles publiables. L’un des résultats les plus importants de cette analyse approfondie est la mise au jour d’un découplage presque complet, au sein même des accords, entre l’objet abonnement et l’objet publication. Bien entendu, l’abonnement est systématiquement configuré dans un monde fermé, soumis à paiement qui déclenche des séries d’identification des circulations légitimes tant du contenu informationnel que des usagers. Il insiste notamment sur les interdictions de réutilisation ou même de copie des articles scientifiques. À l’opposé, la publication en accès ouvert est attachée à un monde régi par l’accès gratuit au contenu, ce qui induit des préoccupations de gestion du workflow et des modalités d’accessibilité. De plus, les différents éléments constitutifs de ces objets contractuels ne sont pas couplés : d’un côté, les lecteurs sont constitués de l’ensemble des membres des institutions abonnées, de l’autre, seuls les auteurs correspondants (« corresponding authors ») sont concernés ; les listes de revues accessibles à la lecture et celles réservées à la publication en accès ouvert sont le plus souvent distinctes ; les workflows ont des objectifs et des organisations matérielles totalement différentes, etc. L’articulation entre les deux objets contractuels relève uniquement d’une formule de distribution financière qui, outre des combinaisons particulières entre l’un et l’autre, permet d’attribuer des étiquettes distinctes aux accords (offset agreement, publish & read, read & publish, read & free articles, read & discount). Au-delà de cette distribution, l’étude des arrangements financiers montre une gamme de dispositions allant d’une prévisibilité budgétaire totale, donc identique aux accords d’abonnement antérieurs, à une incertitude sur le volume de publication ou sur le montant définitif des sommes échangées. Les modalités concrètes de calcul des montants associés à la publication en accès ouvert sont relativement variées. S’il existe effectivement des formules récurrentes (volume d’articles multiplié par un prix individuel, reprise de la moyenne des sommes totales d’APC des années précédentes...), le calcul des sommes en jeu est toujours le résultat d’une négociation singulière entre un consortium et un éditeur scientifique, et aboutit parfois à des formules originales et complexes. À ce titre, l’espace des possibles en matière de formules financières n’est jamais totalement clos. Par ailleurs, la volonté des consortiums d’opérer une « transformation » de leurs accords vers la publication à coût constant renvoie à des définitions diversifiées du « coût » (inclusion ou non des dépenses d’APC préexistantes) et de la constance (admission ou pas d’une « inflation » à 2 ou 3%). De plus, nous n’avons observé aucune disposition contractuelle permettant d’anticiper les sommes en jeu au-delà de l’horizon temporel de l’accord courant. La grande diversité des accords provient d’une part des conditions initiales des relations entre consortiums et éditeurs scientifiques – les sommes dépensées en abonnement étant le point de départ des nouveaux accords –, d’autre part des objectifs de chaque partie. Même si cette étude excluait volontairement les négociations, les accords portent des traces de ces objectifs. Ainsi, de nombreux accords sont de nature explicitement expérimentale, quand certains visent un contrôle budgétaire strict, ou d’autres ambitionnent, dans la période plus récente, la publication du plus grand nombre possible d’articles en accès ouvert. C’est dans ce dernier cas qu’on touche à l’ambiguïté des attentes générales sur les accords transformants. En effet, pour les consortiums, la dimension « transformante » consiste essentiellement à transférer les sommes traditionnellement allouées à l’abonnement vers la publication en accès ouvert. Mais l’objectif n’est jamais de transformer le modèle économique des revues, c'est-à-dire de faire basculer des revues sous abonnement ou hybrides en revues entièrement en accès ouvert. D’ailleurs, aucune clause ne vise une telle fin – à l’exception du modèle d’accord proposé par l’éditeur ACM. Du côté des éditeurs, et notamment de Springer, le caractère cumulatif des accords nationaux passés vise à projeter un monde de la publication où l’accès ouvert devient de fait quantitativement très dominant, sans pour autant modifier de manière pérenne le modèle économique de leurs revues. Notre étude montre que les accords transformants actuels ne permettent pas d’assurer de manière durable une transition de l’économie de la publication vers l’accès ouvert, dans la mesure où ils n’offrent pas de garantie sur le contrôle des dépenses ni sur la pérennité de l’ouverture des contenus. L’avenir des relations entre consortium et éditeur demeure largement indéterminé.
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5

Galili, Naftali, Roger P. Rohrbach, Itzhak Shmulevich, Yoram Fuchs, and Giora Zauberman. Non-Destructive Quality Sensing of High-Value Agricultural Commodities Through Response Analysis. United States Department of Agriculture, October 1994. http://dx.doi.org/10.32747/1994.7570549.bard.

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Анотація:
The objectives of this project were to develop nondestructive methods for detection of internal properties and firmness of fruits and vegetables. One method was based on a soft piezoelectric film transducer developed in the Technion, for analysis of fruit response to low-energy excitation. The second method was a dot-matrix piezoelectric transducer of North Carolina State University, developed for contact-pressure analysis of fruit during impact. Two research teams, one in Israel and the other in North Carolina, coordinated their research effort according to the specific objectives of the project, to develop and apply the two complementary methods for quality control of agricultural commodities. In Israel: An improved firmness testing system was developed and tested with tropical fruits. The new system included an instrumented fruit-bed of three flexible piezoelectric sensors and miniature electromagnetic hammers, which served as fruit support and low-energy excitation device, respectively. Resonant frequencies were detected for determination of firmness index. Two new acoustic parameters were developed for evaluation of fruit firmness and maturity: a dumping-ratio and a centeroid of the frequency response. Experiments were performed with avocado and mango fruits. The internal damping ratio, which may indicate fruit ripeness, increased monotonically with time, while resonant frequencies and firmness indices decreased with time. Fruit samples were tested daily by destructive penetration test. A fairy high correlation was found in tropical fruits between the penetration force and the new acoustic parameters; a lower correlation was found between this parameter and the conventional firmness index. Improved table-top firmness testing units, Firmalon, with data-logging system and on-line data analysis capacity have been built. The new device was used for the full-scale experiments in the next two years, ahead of the original program and BARD timetable. Close cooperation was initiated with local industry for development of both off-line and on-line sorting and quality control of more agricultural commodities. Firmalon units were produced and operated in major packaging houses in Israel, Belgium and Washington State, on mango and avocado, apples, pears, tomatoes, melons and some other fruits, to gain field experience with the new method. The accumulated experimental data from all these activities is still analyzed, to improve firmness sorting criteria and shelf-life predicting curves for the different fruits. The test program in commercial CA storage facilities in Washington State included seven apple varieties: Fuji, Braeburn, Gala, Granny Smith, Jonagold, Red Delicious, Golden Delicious, and D'Anjou pear variety. FI master-curves could be developed for the Braeburn, Gala, Granny Smith and Jonagold apples. These fruits showed a steady ripening process during the test period. Yet, more work should be conducted to reduce scattering of the data and to determine the confidence limits of the method. Nearly constant FI in Red Delicious and the fluctuations of FI in the Fuji apples should be re-examined. Three sets of experiment were performed with Flandria tomatoes. Despite the complex structure of the tomatoes, the acoustic method could be used for firmness evaluation and to follow the ripening evolution with time. Close agreement was achieved between the auction expert evaluation and that of the nondestructive acoustic test, where firmness index of 4.0 and more indicated grade-A tomatoes. More work is performed to refine the sorting algorithm and to develop a general ripening scale for automatic grading of tomatoes for the fresh fruit market. Galia melons were tested in Israel, in simulated export conditions. It was concluded that the Firmalon is capable of detecting the ripening of melons nondestructively, and sorted out the defective fruits from the export shipment. The cooperation with local industry resulted in development of automatic on-line prototype of the acoustic sensor, that may be incorporated with the export quality control system for melons. More interesting is the development of the remote firmness sensing method for sealed CA cool-rooms, where most of the full-year fruit yield in stored for off-season consumption. Hundreds of ripening monitor systems have been installed in major fruit storage facilities, and being evaluated now by the consumers. If successful, the new method may cause a major change in long-term fruit storage technology. More uses of the acoustic test method have been considered, for monitoring fruit maturity and harvest time, testing fruit samples or each individual fruit when entering the storage facilities, packaging house and auction, and in the supermarket. This approach may result in a full line of equipment for nondestructive quality control of fruits and vegetables, from the orchard or the greenhouse, through the entire sorting, grading and storage process, up to the consumer table. The developed technology offers a tool to determine the maturity of the fruits nondestructively by monitoring their acoustic response to mechanical impulse on the tree. A special device was built and preliminary tested in mango fruit. More development is needed to develop a portable, hand operated sensing method for this purpose. In North Carolina: Analysis method based on an Auto-Regressive (AR) model was developed for detecting the first resonance of fruit from their response to mechanical impulse. The algorithm included a routine that detects the first resonant frequency from as many sensors as possible. Experiments on Red Delicious apples were performed and their firmness was determined. The AR method allowed the detection of the first resonance. The method could be fast enough to be utilized in a real time sorting machine. Yet, further study is needed to look for improvement of the search algorithm of the methods. An impact contact-pressure measurement system and Neural Network (NN) identification method were developed to investigate the relationships between surface pressure distributions on selected fruits and their respective internal textural qualities. A piezoelectric dot-matrix pressure transducer was developed for the purpose of acquiring time-sampled pressure profiles during impact. The acquired data was transferred into a personal computer and accurate visualization of animated data were presented. Preliminary test with 10 apples has been performed. Measurement were made by the contact-pressure transducer in two different positions. Complementary measurements were made on the same apples by using the Firmalon and Magness Taylor (MT) testers. Three-layer neural network was designed. 2/3 of the contact-pressure data were used as training input data and corresponding MT data as training target data. The remaining data were used as NN checking data. Six samples randomly chosen from the ten measured samples and their corresponding Firmalon values were used as the NN training and target data, respectively. The remaining four samples' data were input to the NN. The NN results consistent with the Firmness Tester values. So, if more training data would be obtained, the output should be more accurate. In addition, the Firmness Tester values do not consistent with MT firmness tester values. The NN method developed in this study appears to be a useful tool to emulate the MT Firmness test results without destroying the apple samples. To get more accurate estimation of MT firmness a much larger training data set is required. When the larger sensitive area of the pressure sensor being developed in this project becomes available, the entire contact 'shape' will provide additional information and the neural network results would be more accurate. It has been shown that the impact information can be utilized in the determination of internal quality factors of fruit. Until now,
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6

EXPERIMENTS ON BOLTED CONNECTIONS IN COLD-ROLLED ALUMINIUM PORTAL FRAMES. The Hong Kong Institute of Steel Construction, August 2022. http://dx.doi.org/10.18057/icass2020.p.241.

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Анотація:
The use of portal frame systems composed of cold-rolled aluminium profiles is likely to be a new structural solution in corrosive environments. In such structural systems, stainless steel bolts are commonly used as connectors to fasten various aluminium components in the full-scale systems. In these connections, the point fasteners may experience either shear force, torque and/or a combination of both, leading to complex behaviours of the connections. While the failure may occur at a bolt, the other structural components are still in the elastic state. Hence, investigation into the load-deformation responses of bolt connectors is essential to further understand the complexity of bolted connections in the portal frame systems. In this study, experiments on different configurations of bolted connections subjected to shear force and/or torque were carried out at the University of Sydney to investigate the behaviour and to provide the load-deformation characteristics of the bolted connections
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