Journal articles: 'IRM structurale'

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Rahal, Fadia. "Brèves de l’EULAR 2015 Imagerie rhumatologique." Batna Journal of Medical Sciences (BJMS) 2, no. 1 (September 15, 2015): S21—S22. http://dx.doi.org/10.48087/bjms.2015.s218.

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- La ténosynovite ulnaire du carpe est fortement prédictive d’évolution vers une polyarthrite rhumatoïde ; - L’inflammation des articulations sacro-iliaques (IRM-SI) est fortement associée à l’activité de la spondyloarthrite axiale mais seulement chez les hommes ! ; - La progression structurale dans l’arthrose digitale est associée à la présence initiale à l’IRM de synovite et de lésions osseuses.

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Rodrigo, S., S. Mouchet-Mages, C. Oppenheim, M. O. Krebs, J. P. Olié, and J. F. Méder. "Anomalies structurales en IRM et schizophrenie debutante." Journal de Radiologie 89, no. 10 (October 2008): 1226. http://dx.doi.org/10.1016/s0221-0363(08)75632-4.

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Sihombing, Pardomuan Robinson, Ade Marsinta Arsani, Widdia Angraini, and Wisnu Pratiko. "IMPLEMENTASI MODEL SEM PADA HUBUNGAN IPM, IPD DAN IDM." Jurnal Bayesian : Jurnal Ilmiah Statistika dan Ekonometrika 2, no. 2 (September 30, 2022): 107–15. http://dx.doi.org/10.46306/bay.v2i2.33.

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This study aims to determine the influence of the Human Development Index (HDI), poverty and village funds on Village Development approached with the Village Development Index (IPD) and the Building Village Index (IDM). The data used is published data from the Ministry of Villages PDTT and the Central Statistics Agency in 2018. The analysis model used is the Structural Equation Model (SEM) model. The results of the village fund hypothesis test have not had a direct effect on IPD and have not had an indirect effect on IDM. The poverty rate has a significant negative effect directly on IPD and indirectly affects IDM, as well as HDI has a significant positive effect on IPD and indirectly affects IDM. IPD has a significant positive effect directly on IDM. A comprehensive and targeted policy is needed so that village development can take place in a sustainable manner. In addition, supervision is needed related to the use of village funds so that they are right on target in developing villages

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Robert, M., L. Lessard, T. Fenouil, A. Hot, T. Laumonier, A. Bouche, B. Chazaud, N. Streichenberger, and L. Gallay. "POS0490 USEFULNESS OF MHC-II IMMUNO-STAINING ON MUSCLE BIOPSIES IN IDIOPATHIC INFLAMMATORY MYOPATHIES." Annals of the Rheumatic Diseases 81, Suppl 1 (May 23, 2022): 499.2–500. http://dx.doi.org/10.1136/annrheumdis-2022-eular.5186.

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BackgroundIdiopathic inflammatory myopathies (IIMs) constitute a group of acquired muscular diseases that occur during childhood and adulthood, exhibit a variety of phenotypes and are potentially life-threatening. IIM diagnosis considers clinical, serological, and histological data. Muscle pathological analysis of IIM patients gives relevant elements for the diagnosis (immune cell infiltrate, vascular and connective tissues, as well as myofiber morphology). Immunochemistry (IHC) labeling for major histocompatibility complex class I (MHC-I), and C5b9, that are negative in normal muscle, appeared of interest in IIM diagnosis and the understanding of IIM pathogenesis. In normal muscle, myofibers are negative for MHC-II IHC. Its interest in the neuropathological exam of IIM muscle remains to be better characterized.ObjectivesThis study aims to analyze the pattern of MHC-II expression in various IIMs.MethodsA historical cohort was designed using the MYOLYON register (IIM patients diagnosed between 2016 and 2020 at the University Hospital of Lyon, France). Inclusion criteria were IIM diagnosis that was established histologically and available frozen muscle samples for additional analyses. Exclusion criterium was any treatment before muscle biopsy. Demographical data and final diagnosis were collected retrospectively from medical records. A centralized, standardized, and blind analysis of muscle MHC-II immuno-staining was conducted to define the various patterns of MHC-II by myofibers and by capillaries. The study complied with ethical requirements.ResultsSeventy-three patients were included: 23 dermatomyositis (DM), 13 anti-synthetase syndrome (ASS), 13 immune-mediated necrotizing myopathies (IMNM), 13 inclusion body myositis (IBM), and 11 overlap myositis (OM). MHC-II immuno-staining of myofibers or capillaries was abnormal for 91.8% of the analyzed biopsies (Figure 1). The analysis of MHC-II myofiber immuno-staining revealed distinguishable patterns according to IIM subtype: the labeling was diffuse in IBM (69.2%, n=9/13), perifascicular in ASS (61.5%, n=8/13), and variable in OM (patchy for 27.3% n=3/11 or clustered for 36.4%, n=4/11). MHC-II immuno-staining was negative in IMNM (84.6%, n=11/13) and in DM (47.8%, n=11/23). DM exhibiting positive MHC-II myofibers (n=12) were associated with the presence of anti-TIF1γ, anti-NXP2 and anti-SAE auto antibodies (n=5, n=3 and n=2, respectively). Among the 12 patients, there were juvenile cases (n=5, 41.7%) or DM associated with ongoing neoplasia (n=4, 33.3%). Three main architectures were described for capillaries: giant, leaky and capillary dropout. Patterns of MHC-II positive capillaries were the following: DM was characterized by capillary dropout (68.2%), IMNM showed leaky capillaries (75.0%), IBM giant capillaries (66.7%), ASS exhibited both giant (61.5%) and/or leaky (58.3%) capillaries, while OM showed giant (63.6%) or/and leaky (80.0%) capillaries and capillaries dropout (60.0%).ConclusionThe present work establishes the usefulness of MHC-II immuno-staining for IIM diagnosis, and gives additional elements on the impairment of myofibers and capillaries in the various IIM subgroups. MHC-II expression is known to be induced by inflammatory cytokine such as interferon type II. This could be linked to myofiber and/or capillary impairment in some IIMs, such as IBM, ASS and OM. These results also support the implication of vasculopathy in IIM pathogenesis, with various structural and cellular consequences regarding the different subgroups. Finally, MHC-II immuno-staining in IIM muscle biopsies enables a foremost analysis of myofibers and capillaries, and represents an additional biomarker to distinguish IIM subgroups.References[1]De Bleecker, J.L. et al. 205th ENMC International Workshop: Pathology diagnosis of idiopathic inflammatory myopathies part II 28-30 March 2014, Naarden, The Netherlands. Neuromuscul Disord 2015, 25, 268-272.Disclosure of InterestsNone declared.

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Li, Yaxin, Guopeng Wang, Ningning Li, Yuxin Wang, Qinyu Zhu, Huarui Chu, Wenjun Wu, et al. "Structural insights into immunoglobulin M." Science 367, no. 6481 (February 6, 2020): 1014–17. http://dx.doi.org/10.1126/science.aaz5425.

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Immunoglobulin M (IgM) plays a pivotal role in both humoral and mucosal immunity. Its assembly and transport depend on the joining chain (J-chain) and the polymeric immunoglobulin receptor (pIgR), but the underlying molecular mechanisms of these processes are unclear. We report a cryo–electron microscopy structure of the Fc region of human IgM in complex with the J-chain and pIgR ectodomain. The IgM-Fc pentamer is formed asymmetrically, resembling a hexagon with a missing triangle. The tailpieces of IgM-Fc pack into an amyloid-like structure to stabilize the pentamer. The J-chain caps the tailpiece assembly and bridges the interaction between IgM-Fc and the polymeric immunoglobulin receptor, which undergoes a large conformational change to engage the IgM-J complex. These results provide a structural basis for the function of IgM.

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Jung, Jong-Hyun, and Jae-Cheol Lee. "Development of IDM for BIM based Structural Steel Member Design." Journal of the Korea Academia-Industrial cooperation Society 16, no. 2 (February 28, 2015): 1434–40. http://dx.doi.org/10.5762/kais.2015.16.2.1434.

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Zakharov, V. D., S. A. Borzenok, S. V. Kolesnik, I. M. Gorshkov, A. I. Kolesnik, V. I. Shestopalov, A. V. Miridonova, and D. S. Ostrovsky. "OLINiOAL AND MoRpHoLoGiOAL outcomes AND BENEFiT oF EARLY iDiopATHiO EpiRETiNAL MEMBRANES SURGERY." Aspirantskiy Vestnik Povolzhiya 19, no. 1-2 (March 15, 2019): 70–79. http://dx.doi.org/10.17816/2072-2354.2019.19.1.70-79.

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Surgical treatment of iERM improves or stabilizes visual acuity (VA), decreases metamorphopsia, and restores macular anatomy. Nevertheless patients with low preoperative VA do not enjoy complete recovery after membrane removal. Limited restoration of the VA in these patients can be due to chronic traction of retina, vascular leakage and persistent cystoid macular edema. All these factors restrict the restoration of macular anatomy and function. Objective. The purpose is to investigate the functional, structural and morphological outcomes of iERM surgical treatment in different proliferation phase. Materials and methods. 60 patients were divided into 3 groups: 1 group - patients with VA 0.7-0.9; 2 group - patients with VA 0.3-0.6; 3 group with VA 0.1-0.3. Idiopathic ERM/ILM samples from vitrectomy were analyzed for glial acidic fibrillary protein (GFAP), cellular retinaldehyde-binding protein (CRALBP), a-SMA, vimentin, CD65 and type II, IV, VI collagen using flat-mount immunohistochemistry. Results. We observed transdifferentiated retinal Muller cells and astrocytes in myofibroblast-like phenotype which induced tissue contraction. In the course of time membranes demonstrated rough extratrecellular matrix component combination. These membranes had strong adhesion to ILM and were removed in the unique block during vitrectomy. An improvement of postoperative best-corrected visual acuity (BCVA), as well as a decrement in central foveal thickness (CFT) was observed in all groups, maximum after 1 year of observation. Postoperative BCVA was better in patients with satisfactory preoperative VA. Comparative analysis of the three groups showed a significant improvement in BCVA and CFT in the first group. These patients have very little macular damage resulting in good recovery of the macular function. Conclusions. We conclude that vitrectomy for early symptomatic iERM is beneficial in preserving excellent vision. Early intervention may prevent the evolvement of non-reversible damage to the outer retina. It is a safe procedure associated with a lower chance of surgical difficulty during ERM/ILM peeling.

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Dénarié, Delphine, and Hubert Marotte. "Évaluer les lésions structurales de la PR : radiographie standard, échographie et IRM." Revue du Rhumatisme Monographies 84, no. 4 (September 2017): 369–75. http://dx.doi.org/10.1016/j.monrhu.2017.06.002.

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Saini, Surinder S., and Azad Kaushik. "Origin of bovine IgM structural variants." Molecular Immunology 38, no. 5 (September 2001): 389–96. http://dx.doi.org/10.1016/s0161-5890(01)00063-3.

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Ward, C., N. Rattanawangcharoen, and C. Gheorghiu. "Impact resonance method for damage detection in carbon-fibre-reinforced polymer–strengthened reinforced concrete beams subjected to fatigue and thermal cycling." Canadian Journal of Civil Engineering 35, no. 11 (November 2008): 1251–60. http://dx.doi.org/10.1139/l08-066.

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Much of North America’s civil infrastructure is rapidly aging and, in some cases, exceeding its design life and load. To combat this, the exploration of simple and effective methods for rehabilitation and structural health monitoring has been receiving much attention in industry and academia. This paper reports on the use of the impact resonance method (IRM) for evaluating the structural health of thermal-cycled reinforced concrete (RC) beams with and without externally strengthened carbon-fibre-reinforced polymer (CFRP) pultruded plates. In the experimental program, 1.2 m long specimens were subjected to 55 thermal cycles ranging from +23 to −18 °C. Fatigue loading consisting of up to two million cycles at high and low stress levels was performed. At pre-determined load cycle intervals, the loading was stopped and the IRM was performed on the specimens. Parameters including the appearance of the fast Fourier transform (FFT) spectrum of the specimens’ vibration, modal fundamental frequencies, and dynamic properties were used to assess damage in the specimen. Conclusions were made regarding the use of the IRM in monitoring the health of strengthened and unstrengthened RC beams subjected to thermal and fatigue cycles.

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Hewlett, Dexter Senanu Kofi, Evans Tee, Kojo Essel-Mensah, and Janet Asabre. "Impact of Institutional Risk Management, Technological Adoption, and Climate Change Adaptation on Ghana’s Crop Productivity." International Journal of Business, Management and Economics 6, no. 1 (February 6, 2025): 21–40. https://doi.org/10.47747/ijbme.v6i1.2618.

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This study investigated the impact of Agricultural Technology Adoption (ATA), Climate Change Adaptation Measures (CCAM), and Institutional Risk Management (IRM) on crop production (CP). The purpose of this study is to assess how these variables influence agricultural productivity and identify the key drivers of successful crop production in the context of climate change and institutional challenges. A quantitative research design was employed utilising survey data collected from farmers across different agricultural regions. Structural equation modelling (SEM) was used for data analysis to examine the relationships between ATA, CCAM, IRM, and CP. The findings indicated that ATA, CCAM, and IRM had a positive and statistically significant effect on crop production. This study highlights that adopting advanced technologies, implementing effective climate change adaptation strategies, and strengthening institutional risk management can significantly enhance crop productivity. This study contributes to the literature by emphasising the importance of technological adoption and risk management strategies in agriculture. These practical implications suggest that policymakers should prioritise the integration of ATA and IRM into agricultural policies to promote sustainable and resilient agricultural practices, thereby improving overall crop production and food security.

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Owens-Young, Jessica, and Caryn N. Bell. "Structural Racial Inequities in Socioeconomic Status, Urban-Rural Classification, and Infant Mortality in US Counties." Ethnicity & Disease 30, no. 3 (July 8, 2020): 389–98. http://dx.doi.org/10.18865/ed.30.3.389.

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Objectives: Despite improvements in infant mortality rates (IMR) in the United States, racial gaps in IMR remain and may be driven by both structural racism and place. This study assesses the relationship between structural racism and race-specific IMR and the role of urban-rural classification on race-specific IMR and Black/White racial gaps in IMR.Methods: We conducted an analysis of variance tests using 2019 County Health Rankings Data to determine differences in structural racism indicators, IMR and other co-variates by urban-rural classification. We used linear regressions to determine the associations between measures of structural racism and county-level health outcomes.Results: Study results suggest that racial inequities in education, work, and homeownership negatively impact Black IMR, especially in large fringe, medium, and small metro counties, and positively impact White IMR. Structural racism is also associated with Black-White gaps in IMR.Conclusions: Factors related to structural racism may not be homogenous or have the same impacts on overall IMR, race-specific IMR, and racial differences in IMR across places. Understanding these differential impacts can help public health professionals and policymakers improve Black infant health and eliminate racial inequities in IMR. Ethn Dis. 2020;30(3):389-398; doi:10.18865/ed.30.3.389

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Davies, Anna M., and Brian J. Sutton. "Human IgG4: a structural perspective." Immunological Reviews 268, no. 1 (October 26, 2015): 139–59. http://dx.doi.org/10.1111/imr.12349.

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Wiersma, Erik J., Cathy Collins, Shafie Fazel, and Marc J. Shulman. "Structural and Functional Analysis of J Chain-Deficient IgM." Journal of Immunology 160, no. 12 (June 15, 1998): 5979–89. http://dx.doi.org/10.4049/jimmunol.160.12.5979.

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Abstract Previous studies have discerned two forms of polymeric mouse IgM: moderately cytolytic (complement-activating) pentamer, which contains J chain, and highly cytolytic hexamer, which lacks J chain. To investigate the relationships among polymeric structure, J chain content, and cytolytic activity, we produced IgM in J chain-deficient and J chain-proficient mouse hybridoma cell lines. Both hexamer and pentamer were produced in the absence as well as the presence of J chain. Hexameric IgM activated (guinea pig) complement approximately 100-fold more efficiently than did J chain-deficient pentamer, which, in turn, was more active than J chain-containing pentamer. These results are consistent with the hypothesis that J chain-containing pentamer cannot activate complement. We also analyzed the structure of IgM-S337, in which the μ-chain bears the C337S substitution. Like normal IgM, IgM-S337 was formed as a hexamer and as both J chain deficient- and J chain-containing pentamers. Unlike normal IgM, IgM-S337 dissociated in SDS into various subunits. For IgM-S337 pentamer, the predominant subunits migrated as μ2κ2 and μ4κ4, and the subunit distribution was unaltered by J chain. However, J chain was found only in the μ2κ2 species, suggesting that some arrangement of inter-μ bonds directs incorporation of J chain. IgM-S337 hexamer also dissociated to μ2κ2 and μ4κ4, but also yielded several species migrating much more slowly in SDS-PAGE than wild-type μ12κ12. To account for these forms, we propose that each μ-chain can interact with three other μ-chains and that some hexameric molecules contain two catenated μ6κ6 circles.

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Gheorghiu, Catalin, Jamal Eddine Rhazi, and Pierre Labossière. "Impact resonance method for fatigue damage detection in reinforced concrete beams with carbon fibre reinforced polymer." Canadian Journal of Civil Engineering 32, no. 6 (December 1, 2005): 1093–102. http://dx.doi.org/10.1139/l05-064.

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This paper reports on the potential of using the impact resonance method (IRM) for detecting fatigue damage in strengthened reinforced concrete (RC) beams. In this experimental program, 1.2 m long RC beams strengthened with a carbon fibre reinforced polymer (CFRP) plate have been employed. The specimens were subjected to fatigue loading under four-point bending for up to 2 × 106 cycles at 3 Hz. The load amplitude was varying from 15% to 75% of the cycles yielding load of the beam. Throughout fatigue testing, the cycling was stopped for IRM measurements to be taken. The obtained data provided information about changes in modal properties, such as, fundamental frequencies and damping ratios. Moreover, the results have shown that the IRM technique was successfully employed in laboratory for detecting fatigue damage in concrete beams strengthened with CFRP laminates.Key words: impact resonance method, modal properties, RC beam, FRP-strengthening, fatigue test, cracking.

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Hu, Jlazhen. "Intoad—An interface between IRM and ADINA." Computers & Structures 47, no. 4-5 (June 1993): 751–56. http://dx.doi.org/10.1016/0045-7949(93)90356-i.

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Aaberge, Rolf, and Ugo Colombino. "Structural Labour Supply Models and Microsimulation." International Journal of Microsimulation 11, no. 1 (2017): 162–97. http://dx.doi.org/10.34196/ijm.00177.

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Meja Lopez, Eliany, and Rohit Malhotra. "Ventricular Tachycardia in Structural Heart Disease." Journal of Innovations in Cardiac Rhythm Management 10, no. 8 (August 1, 2019): 3762–73. http://dx.doi.org/10.19102/icrm.2019.100801.

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Tehrani, Mahsa Vaez, Ali Bagheri, Mohammad Javad Monem, and Shahbaz Khan. "ANALYSING STRUCTURAL AND NON-STRUCTURAL OPTIONS TO IMPROVE UTILITY OF IRRIGATION AREAS USING A SYSTEM DYNAMICS APPROACH." Irrigation and Drainage 61, no. 5 (December 2012): 604–21. http://dx.doi.org/10.1002/ird.1697.

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Suryoatmono, Bambang, and Fedora Marleen Tumena. "Indirect Analysis Method in Design for Stability of Structural Steel Buildings." MEDIA KOMUNIKASI TEKNIK SIPIL 29, no. 1 (October 27, 2023): 11–22. http://dx.doi.org/10.14710/mkts.v29i1.50473.

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There are three methods of design for stability defined in AISC 360-16 Specification for Structural Steel Buildings, namely Direct Analysis Method (DAM), Effective-Length Method (ELM), and First-Order Analysis Method (FOM). DAM is the method that is featured by AISC. Based on DAM, Rafael Sabelli proposed another method called Indirect Analysis Method (IAM). IAM is a new method that has not generally been used, and also has not been included in the AISC Specification. This research is conducted in order to study IAM and compares the analysis results of IAM with those of DAM. Using a nonlinear structural analysis software, design and analysis were conducted for stability design of an eight-story building loaded with dead load, live load, and wind load. IAM provides a simple amplifier approach which is called B3 to address the member inelasticity, member imperfections, and uncertainty in member stiffness. From the study that has been conducted, the analysis results using IAM show close values with those of DAM, in terms of demand-to-capacity ratios, with IAM is more conservative than DAM. The use of IAM simplifies the design process without affecting the economy of the design.

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Erkan, Sultan, and Duran Karakaş. "A theoretical study on cyclometalated iridium (III) complexes by using a density functional theory." Journal of Theoretical and Computational Chemistry 19, no. 02 (March 2020): 2050006. http://dx.doi.org/10.1142/s0219633620500066.

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Cyclometalated iridium (III) complexes (Ir1–Ir4) are calculated in detail with computational chemistry methods. The calculated structural parameters of Ir3 are compared with experimental values and a good fit is obtained. IR spectra are calculated at B3LYP/LANL2DZ/6-31G(d) level in the gases phase. Calculated 1H-NMR chemical shift values of the mentioned complexes are compared with the experimental data and all chemical shifts are assigned to the respective atoms. The quantum chemical parameters such as absolute hardness ([Formula: see text]), absolute softness ([Formula: see text]) electronegativity ([Formula: see text]), chemical potential ([Formula: see text]) and electronic charges ([Formula: see text]) are calculated and are associated with the experimental anti-cancer properties of the related complexes. Nonlinear optic properties of the Ir1–Ir4 were investigated with the average linear polarizability ([Formula: see text]), the anisotropy of the polarizability ([Formula: see text]), first hyperpolarizability ([Formula: see text]) values. Hole transfer ([Formula: see text]), electron transfer integrals ([Formula: see text]), hole reorganization energies ([Formula: see text]) and electron reorganization energies ([Formula: see text]) are examined. In addition, molecular docking study was performed. It was found that the molecular docking results are similar to the experimental anti-cancer trend.

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McNamara, D. K., and J. S. Ahearn. "Adhesive bonding of steel for structural applications." International Materials Reviews 32, no. 1 (January 1987): 292–306. http://dx.doi.org/10.1179/imr.1987.32.1.292.

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Bamberger, M. "Laser surface hardening of structural ferrous alloys." International Materials Reviews 43, no. 5 (August 1998): 189–203. http://dx.doi.org/10.1179/imr.1998.43.5.189.

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Marchand, Christophe H., Simona Fermani, Jacopo Rossi, Libero Gurrieri, Daniele Tedesco, Julien Henri, Francesca Sparla, Paolo Trost, Stéphane D. Lemaire, and Mirko Zaffagnini. "Structural and Biochemical Insights into the Reactivity of Thioredoxin h1 from Chlamydomonas reinhardtii." Antioxidants 8, no. 1 (January 1, 2019): 10. http://dx.doi.org/10.3390/antiox8010010.

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Thioredoxins (TRXs) are major protein disulfide reductases of the cell. Their redox activity relies on a conserved Trp-Cys-(Gly/Pro)-Pro-Cys active site bearing two cysteine (Cys) residues that can be found either as free thiols (reduced TRXs) or linked together by a disulfide bond (oxidized TRXs) during the catalytic cycle. Their reactivity is crucial for TRX activity, and depends on the active site microenvironment. Here, we solved and compared the 3D structure of reduced and oxidized TRX h1 from Chlamydomonas reinhardtii (CrTRXh1). The three-dimensional structure was also determined for mutants of each active site Cys. Structural alignments of CrTRXh1 with other structurally solved plant TRXs showed a common spatial fold, despite the low sequence identity. Structural analyses of CrTRXh1 revealed that the protein adopts an identical conformation independently from its redox state. Treatment with iodoacetamide (IAM), a Cys alkylating agent, resulted in a rapid and pH-dependent inactivation of CrTRXh1. Starting from fully reduced CrTRXh1, we determined the acid dissociation constant (pKa) of each active site Cys by Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry analyses coupled to differential IAM-based alkylation. Based on the diversity of catalytic Cys deprotonation states, the mechanisms and structural features underlying disulfide redox activity are discussed.

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Klimovich, V. B. "IgM and its receptors: Structural and functional aspects." Biochemistry (Moscow) 76, no. 5 (May 2011): 534–49. http://dx.doi.org/10.1134/s0006297911050038.

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Wang, Wei-Chih, Chia-Li Lin, Shih-Hsu Wang, Jang-Jeng Liu, and Ming-Tsung Lee. "APPLICATION OF IMPORTANCE-SATISFACTION ANALYSIS AND INFLUENCE-RELATIONS MAP TO EVALUATE DESIGN DELAY FACTORS." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 20, no. 4 (March 10, 2014): 497–510. http://dx.doi.org/10.3846/13923730.2013.801922.

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Design delays can negatively influence the total completion time of a facility construction project. Knowing the factors to which design delays are most sensitive supports the time management of designs. However, factors that cause design delays are several and interrelated. This study proposes a new model to identify key factors that drive design delays. The core of the model integrates importance-satisfaction analysis (ISA) and an influence-relations map (IRM). The ISA evaluates the performance of each delay factor, while the IRM captures the causal relationships among factors. Additionally, the IRM is generated using a decision making trial and evaluation laboratory technique (DEMATEL). The model is applied to a real-world high-tech facility construction project to indicate the strengths of the model. In this investigation, four first-level delay factors and 17 second-level delay sub-factors are derived. The factor of “organization's decision making and budget constraints” is identified as the key driver of design delays in the project of interest. The results support management in determining which problem factors should be given priority attention. The proposed model can be employed in other decision-making situations that involve interrelated factors.

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Vilda, Dovile, Rachel Hardeman, Lauren Dyer, Katherine P. Theall, and Maeve Wallace. "Structural racism, racial inequities and urban–rural differences in infant mortality in the US." Journal of Epidemiology and Community Health 75, no. 8 (January 27, 2021): 788–93. http://dx.doi.org/10.1136/jech-2020-214260.

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BackgroundWhile evidence shows considerable geographic variations in county-level racial inequities in infant mortality, the role of structural racism across urban–rural lines remains unexplored. The objective of this study was to examine the associations between county-level structural racism (racial inequity in educational attainment, median household income and jail incarceration) and infant mortality and heterogeneity between urban and rural areas.MethodsUsing linked live birth/infant death data provided by the National Center for Health Statistics, we calculated overall and race-specific 2013–2017 5-year infant mortality rates (IMRs) per 1000 live births in every county. Racially stratified and area-stratified negative binomial regression models estimated IMR ratios and 95% CIs associated with structural racism indicators, adjusting for county-level confounders. Adjusted linear regression models estimated associations between structural racism indicators and the absolute and relative racial inequity in IMR.ResultsIn urban counties, structural racism indicators were associated with 7%–8% higher black IMR, and an overall structural racism score was associated with 9% greater black IMR; however, these findings became insignificant when adjusting for the region. In white population, structural racism indicators and the overall structural racism score were associated with a 6% decrease in urban white IMR. Both absolute and relative racial inequity in IMR were exacerbated in urban counties with greater levels of structural racism.ConclusionsOur findings highlight the complex relationship between structural racism and population health across urban–rural lines and suggest its contribution to the maintenance of health inequities in urban settings.

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Bromage, Erin, Priti Kataria, and Fraancisco Ramirez-Gomez. "The structure of rainbow trout IgM influences antibody-mediated phagocytosis of bacteria (160.16)." Journal of Immunology 188, no. 1_Supplement (May 1, 2012): 160.16. http://dx.doi.org/10.4049/jimmunol.188.supp.160.16.

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Abstract The tetrameric IgM molecule is the dominant immunoglobulin found in the serum of fish. In contrast to the fully polymerized mammalian IgM, teleost IgM is variably disulfide cross-linked resulting in considerable structural diversity. Recently, it was revealed that following vaccination, rainbow trout alter the assembly of their antigen-specific IgM. It was hypothesized that these different IgM forms may allow this molecule to switch effector functions. To investigate whether there was a link between structure and function, we used serum with differing IgM structural profiles and evaluated their ability to mediate phagocytosis. We discovered that when IgM was fully disulfide cross-linked it increased phagocytosis of the antibody-opsonized bacteria. Conversely, when a larger percentage of the IgM was held together by electrostatic forces, phagocytosis was diminished. Control experiments proved that differences in antibody coating were not responsible for the differences in phagocytic potential of the antibody pools. Thus, rainbow trout IgM that is more heavily disulfide polymerized facilitates antibody-mediated phagocytosis more effectively. To our knowledge, this is the first time that IgM structural diversity has been demonstrated to affect a biological function critical for the protection against infectious disease.

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Bajwa, Deepinder S., Arun Rai, and Arkalgud Ramaprasad. "The Structural Context of Executive Information Systems Adoption." Information Resources Management Journal 11, no. 3 (July 1998): 28–38. http://dx.doi.org/10.4018/irmj.1998070103.

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Riva, Alessandro, Bernard Tandler, Felice Loffredo, Edwin Vazquez, and Charles Hoppel. "Structural differences in two biochemically defined populations of cardiac mitochondria." American Journal of Physiology-Heart and Circulatory Physiology 289, no. 2 (August 2005): H868—H872. http://dx.doi.org/10.1152/ajpheart.00866.2004.

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To determine whether there are structural differences in two topologically separated, biochemically defined mitochondrial populations in rat heart myocytes, the interior of these organelles was examined by high-resolution scanning electron microscopy. On the basis of a count of 159 in situ subsarcolemmal mitochondria (SSM, i.e., those that directly abut the sarcolemma), these organelles possess mainly lamelliform cristae (77%), whereas the cristae in in situ interfibrillar mitochondria (IFM, i.e., those situated between the myofibrils, n = 300) are mainly tubular (55%) or a mixture of tubular and lamelliform (24%). Isolated SSM ( n = 374), similar to their in situ counterparts, have predominantly lamelliform cristae (75%). The proportions of crista types in isolated IFM ( n = 337) have been altered, with only 20% of these organelles retaining exclusively tubular cristae, whereas 58% are mixed; of the latter, lamelliform cristae predominate. This finding suggests that, in contrast to SSM, the cristae in IFM are structurally plastic, changing during isolation. These observations on >1,000 organelles provide the first quantitative morphological evidence for definitive differences between the two populations of cardiac mitochondria.

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Hamidjaja, Raditijo, Jérémie Capoulade, Laura Catón, and Colin J. Ingham. "The cell organization underlying structural colour is involved in Flavobacterium IR1 predation." ISME Journal 14, no. 11 (September 1, 2020): 2890–900. http://dx.doi.org/10.1038/s41396-020-00760-6.

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Abstract Flavobacterium IR1 is a gliding bacterium with a high degree of colonial organization as a 2D photonic crystal, resulting in vivid structural coloration when illuminated. Enterobacter cloacae B12, an unrelated bacterium, was isolated from the brown macroalga Fucus vesiculosus from the same location as IR1. IR1 was found to be a predator of B12. A process of surrounding, infiltration, undercutting and killing of B12 supported improved growth of IR1. A combination of motility and capillarity facilitated the engulfment of B12 colonies by IR1. Predation was independent of illumination. Mutants of IR1 that formed photonic crystals less effectively than the wild type were reduced in predation. Conversely, formation of a photonic crystal was not advantageous in resisting predation by Rhodococcus spp. PIR4. These observations suggest that the organization required to create structural colour has a biological function (facilitating predation) but one that is not directly related to the photonic properties of the colony. This work is the first experimental evidence supporting a role for this widespread type of cell organization in the Flavobacteriia.

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Hillson, J. L., N. S. Karr, I. R. Oppliger, M. Mannik, and E. H. Sasso. "The structural basis of germline-encoded VH3 immunoglobulin binding to staphylococcal protein A." Journal of Experimental Medicine 178, no. 1 (July 1, 1993): 331–36. http://dx.doi.org/10.1084/jem.178.1.331.

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The ability of human VH3 immunoglobulins (Ig) to bind to staphylococcal protein A (SPA) via their Fab region is analogous to the binding of bacterial superantigens to T cell receptors. The present report establishes the structural basis for the interaction of SPA and VH3 Ig. We have studied a panel of 27 human monoclonal IgM that were derived from fetal B lymphocytes. As such, these IgM were expected to be encoded by unmutated germline genes. Binding to SPA in ELISA occurred with 15 of 15 VH3 IgM, but none of 12 IgM from the VH1, VH4, VH5, or VH6 families. The VH sequences of the 27 IgM were derived from 20 distinct VH elements, including 11 from the VH3 family. Use of D, JH, and CL genes was similar among VH3 and non-VH3 IgM. A comparison of the corresponding VH protein sequences, and those of previously studied IgM, identified a probable site for SPA binding that includes VH3 residues in framework region 3 (FR3), and perhaps FR1 and 3' complementary determining region 2. The results thus demonstrate that among human IgM, specificity for SPA is encoded by at least 11 different VH3 germline genes. Furthermore, like the T cell superantigens, SPA likely binds to residues in the VH framework region, outside the classical antigen-binding site of the hypervariable loops.

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陈, 科. "Structural Strength Analysis of Offshore Wind Turbine Installation Vessel." International Journal of Mechanics Research 05, no. 01 (2016): 26–33. http://dx.doi.org/10.12677/ijm.2016.51004.

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Elmegreen, Bruce G., Tayfun Gokmen, and Biruk Habtemariam. "Gridlock Models with the IBM Mega Traffic Simulator: Dependency on Vehicle Acceleration and Road Structure." Journal of Sensor Networks and Data Communications 4, no. 3 (December 20, 2024): 01–18. https://doi.org/10.33140/jsndc.04.03.07.

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Rush hour and sustained traffic flows in eight cities are studied using the IBM Mega Traffic Simulator to understand the importance of road structures and vehicle acceleration in the prevention of gridlock. Individual cars among the tens of thousands launched are monitored at every simulation time step using live streaming data transfer from the simulation software to analysis software on another computer. A measure of gridlock is the fraction of cars moving at less than 30% of their local road speed. Plots of this fraction versus the instantaneous number of cars on the road show hysteresis during rush hour simulations, indicating that it can take twice as long to unravel clogged roads as fill them. The area under the hysteresis loop is used as a measure of gridlock to compare different cities normalized to the same central areas. The differences between cities, combined with differences between idealized models using square or triangular road grids, indicate that gridlock tends to occur most when there are a small number of long roads that channel large fractions of traffic. These long roads help light traffic flow but they make heavy flows worse. Increasing the speed on these long roads makes gridlock even worse in heavy conditions. City throughput rates are also modeled using a smooth ramp up to a constant vehicle launch rate. Models with increasing acceleration for the same road speeds show clear improvements in city traffic flow as a result of faster interactions at intersections and merging points. However, these improvements are relatively small when the gridlock is caused by long roads having many cars waiting to exit at the same intersection. In general, gridlock in our models begins at intersections regardless of the available road space in the network

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Thusberg, J., and M. Vihinen. "The structural basis of hyper IgM deficiency – CD40L mutations." Protein Engineering, Design and Selection 20, no. 3 (January 1, 2007): 133–41. http://dx.doi.org/10.1093/protein/gzm004.

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Salem, G., D. W. Wittig, T. G. Foote, B. J. Robbins, C. Hirko, D. O. Forlenza, F. Motika, et al. "Structural and functional test of IBM System z10 chips." IBM Journal of Research and Development 53, no. 1 (January 2009): 5:1–5:11. http://dx.doi.org/10.1147/jrd.2009.5388583.

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Diaw, L., C. Magnac, O. Pritsch, M. Buckle, P. M. Alzari, and G. Dighiero. "Structural and affinity studies of IgM polyreactive natural autoantibodies." Journal of Immunology 158, no. 2 (January 15, 1997): 968–76. http://dx.doi.org/10.4049/jimmunol.158.2.968.

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Abstract Natural polyreactive autoantibodies (NAA) are an important component of the normal B cell repertoire. One intriguing characteristic of these Abs is their binding to various dissimilar Ags. It has been generally assumed that these Abs bind the Ags with low affinity, and are encoded by germline genes. We have used surface plasmon resonance to determine binding of avidities, and conducted a structural analysis of five murine monoclonal natural autoantibodies displaying a typical polyreactive binding pattern against cytoskeleton Ags and DNA. We show that 1) all the five Abs bind the different Ags with kinetic constants similar to those observed for immune Abs; 2) they express a restricted set of V(H) and V(L) genes, since the same V(H) gene is expressed by three out of the five, and one particular Vkappa gene was expressed twice. In addition, a single D gene segment was used by three of the five Abs; and 3) they express, in most cases, genes in a close germline configuration. Our amino acid sequence and modeling studies show that the distribution of exposed side chains in the NAA paratopes is close to the general pattern observed in the complementarity-determining regions (CDRs) of variable domains from immune Abs. Although CDR3 regions of the heavy chain have been postulated to play a major role in determining polyreactivity on the basis of recombinatorial experiments, our results failed to show any distinctive particularity of this region in terms of length or charge when compared with classical immune Abs.

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DOMBRINKKURTZMAN, M., M. LACY, and E. VOSSJR. "Structural properties of an anti-fluorescein monoclonal igm cryoglobulin☆." Molecular Immunology 26, no. 8 (August 1989): 779–87. http://dx.doi.org/10.1016/0161-5890(89)90038-2.

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Pasman, Yfke, and Azad Kaushik. "Elucidating the role of bovine heavy- and light-chain variable domains in polyspecific antigen-binding (P6104)." Journal of Immunology 190, no. 1_Supplement (May 1, 2013): 141.15. http://dx.doi.org/10.4049/jimmunol.190.supp.141.15.

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Abstract The bovine antibody repertoire is generated from a limited germline sequence divergence as well as combinatorial diversity. Generation of an exceptionally long CDR3H (up to 61 amino acids) in the heavy chain variable region (VH) provides an additional mechanism to generate antibody diversity, not found in other species to date. These long CDR3H loops, present in polyspecific IgM, originate from VDJ recombination encoded by a specific VH gene, unusually long single DH-gene (capable of encoding up to 51 codons) and insertion of 15-18 base long conserved short nucleotide sequences (CSNS) specifically at VH-DH junction. In cattle, it is thought that antigen-binding is mainly a function of the variable-region of the heavy chain where light chain provides only structural support. To test this hypothesis, single chain variable fragment (scFv) and single domains (Fd) from polyspecific IgM were constructed. Both purified scFv as well as FdVH showed polyspecific binding to structurally dissimilar antigens in an ELISA. Whether scFv and FdVH bind to multiple epitopes on an antigen or if they recognize the same epitope can now be determined. The structural-functional complexities of these antibody fragments and the role of the heavy- and light-chains in antigen-binding will be discussed. [Supported by NSERC Canada]

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Delgado, José C. "Architectural Styles for Distributed Interoperability." Information Resources Management Journal 26, no. 4 (October 2013): 40–65. http://dx.doi.org/10.4018/irmj.2013100103.

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SOA and REST are the two main architectural styles used for distributed applications. Current SOA implementations use Web Services, which have a flexible service interface but lack resource structure. Current REST implementations use HTTP, with good structural support (through URIs) but fixed service interface, leading to a significant mismatch in modeling some application artifacts. In addition, current data description languages support distributed interoperability by schema sharing (XML) or predefined media types (JSON). This paper makes two main proposals: an architectural style, Structural Service, capable of combining resource structure with flexible services, and a distributed interoperability mechanism, based on structural compliance and conformance, which supports partial interoperability and reduces coupling between interacting services while ensuring that the interoperability requirements of the application are satisfied. Since current technologies do not readily support these proposals, the author developed a language and its execution platform that supports structural services and compliance and conformance.

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Richter, Ekkehard, Hermine Hitzler, Heiko Zimmermann, Rolf Hagedorn, and G�nter Fuhr. "Trace formation during locomotion of L929 mouse fibroblasts continuously recorded by interference reflection microscopy (IRM)." Cell Motility and the Cytoskeleton 47, no. 1 (2000): 38–47. http://dx.doi.org/10.1002/1097-0169(200009)47:1<38::aid-cm4>3.0.co;2-w.

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Memarian, Negar, Paul M. Thompson, Jerome Engel, and Richard J. Staba. "Quantitative analysis of structural neuroimaging of mesial temporal lobe epilepsy." Imaging in Medicine 5, no. 3 (June 2013): 219–35. http://dx.doi.org/10.2217/iim.13.28.

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Petrakis, P. E., and S. Kotsios. "A Nonlinear Control Model of Growth, Risk and Structural Change." Intelligent Information Management 02, no. 02 (2010): 80–89. http://dx.doi.org/10.4236/iim.2010.22010.

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de Santana Nunes, Danilo, Jose Luis Vital de Brito, and Graciela Nora Doz. "A low-cost data acquisition system for dynamic structural identification." IEEE Instrumentation & Measurement Magazine 22, no. 5 (October 2019): 64–72. http://dx.doi.org/10.1109/imm.2019.8868280.

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Turner, Vivian M., and Neil A. Mabbott. "Structural and functional changes to lymph nodes in ageing mice." Immunology 151, no. 2 (March 16, 2017): 239–47. http://dx.doi.org/10.1111/imm.12727.

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Yin, Yiyuan, Yili Li, and Roy A. Mariuzza. "Structural basis for self-recognition by autoimmune T-cell receptors." Immunological Reviews 250, no. 1 (October 10, 2012): 32–48. http://dx.doi.org/10.1111/imr.12002.

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Lu, Jinghua, and Peter D. Sun. "Structural mechanism of high affinity FcγRI recognition of immunoglobulin G." Immunological Reviews 268, no. 1 (October 26, 2015): 192–200. http://dx.doi.org/10.1111/imr.12346.

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Johnson, D. S., C. Cinnioglu, R. Ross, A. Filby, G. Gemelos, M. Hill, A. Ryan, D. Smotrich, M. Rabinowitz, and M. J. Murray. "Comprehensive analysis of karyotypic mosaicism between trophectoderm and inner cell mass." Molecular Human Reproduction 16, no. 12 (July 19, 2010): 944–49. http://dx.doi.org/10.1093/molehr/gaq062.

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Abstract Aneuploidy has been well-documented in blastocyst embryos, but prior studies have been limited in scale and/or lack mechanistic data. We previously reported preclinical validation of microarray 24-chromosome preimplantation genetic screening in a 24-h protocol. The method diagnoses chromosome copy number, structural chromosome aberrations, parental source of aneuploidy and distinguishes certain meiotic from mitotic errors. In this study, our objective was to examine aneuploidy in human blastocysts and determine correspondence of karyotypes between trophectoderm (TE) and inner cell mass (ICM). We disaggregated 51 blastocysts from 17 couples into ICM and one or two TE fractions. The average maternal age was 31. Next, we ran 24-chromosome microarray molecular karyotyping on all of the samples, and then performed a retrospective analysis of the data. The average per-chromosome confidence was 99.95%. Approximately 80% of blastocysts were euploid. The majority of aneuploid embryos were simple aneuploid, i.e. one or two whole-chromosome imbalances. Structural chromosome aberrations, which are common in cleavage stage embryos, occurred in only three blastocysts (5.8%). All TE biopsies derived from the same embryos were concordant. Forty-nine of 51 (96.1%) ICM samples were concordant with TE biopsies derived from the same embryos. Discordance between TE and ICM occurred only in the two embryos with structural chromosome aberration. We conclude that TE karyotype is an excellent predictor of ICM karyotype. Discordance between TE and ICM occurred only in embryos with structural chromosome aberrations.

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Murtazaliyeva, Alexandra, Gulnara Svyatova, Galina Berezina, Gulfairuz Urazbayeva, and Aigerim Sadyrbekova. "Genes of Inflammation and Placental Function GWAS Associated with Idiopathic Recurrent Miscarriage in the Kazakh Population." Journal of Human Reproductive Sciences 17, no. 1 (2024): 42–49. http://dx.doi.org/10.4103/jhrs.jhrs_134_23.

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ABSTRACT Background: The loss of two or more pregnancies is considered recurrent miscarriage (RM). One of the causes of this pathology is the occurrence of mutations both in pleiotropic and pathway-specific regulators and in structural genes. The simplest type of such mutations is single nucleotide polymorphisms. Aims: The aim of the study is to study the relationship between gene polymorphisms of anti- and pro-inflammatory cytokines – interferon-gamma (T874A), interleukin (IL1B) (C3954T), IL6 (G572C) and IL10 (G1082A); placental function, apoptosis and angiogenesis – apolipoprotein C-III (APOC3) (G5163C), kinase insert domain receptor (A1719T, G1192A), P53 (Arg72Pro) and signal transducer and activator of transcription 3 (STAT3) (C1697G) with the development of idiopathic RM (iRM) in the Kazakh population. Settings and Design: This was a case–control study. Materials and Methods: Molecular genetic studies were performed by TaqMan using a single site-specific amplification and real-time genotyping method in 302 women with iRM and 300 with normal reproduction. DNA isolation from the biomaterial was carried out using kits containing binding magnetic particles. Both samples were analysed for alleles and genotypes for the studied polymorphisms. Statistical Analysis Used: For statistical data processing, Pearson’s criterion, confidence interval (CI) and probability value were taken into account. Results: It was found that the carriage of unfavourable genotypes (G/C, C/C) for the G5163C polymorphism of the APOC3 gene increases the risk of developing iRM by three times (odds ratio = 3.0; 95% CI = 2.24–4.07). Other studied polymorphisms in the genes of ILs, interferon, P53 proapoptotic protein, kinase domain receptor and STAT3 transcription activator were not associated with RM. Conclusion: Significant associations of APOC3 gene genotypes with the development of iRM in the Kazakh population indicate the involvement of the placental system, which is realised by vascularisation defects and defective embryo implantation and leads to early pregnancy termination.

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Muraoka, S., and M. J. Shulman. "Structural requirements for IgM assembly and cytolytic activity. Effects of mutations in the oligosaccharide acceptor site at Asn402." Journal of Immunology 142, no. 2 (January 15, 1989): 695–701. http://dx.doi.org/10.4049/jimmunol.142.2.695.

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Abstract Glycosylation of IgG occurs at asparagine 297 of the gamma H chain and is necessary for the normal capacity of IgG to activate the classical pathway of complement-dependent cytolysis. IgM is glycosylated at five sites in the constant region of the mu H chain, of which glycosylation at asparagine 402 seems analogous to the glycosylation of IgG. In order to assess the importance of glycosylation at asparagine 402 for IgM cytolytic activity, we have used site-directed mutagenesis to produce IgM which is not glycosylated at this position. In particular we have tested the effects of substituting Gln for Asn 402 and Thr-Gly for Gly 403-Thr 404 in the third constant region domain. We tested the effects of these substitutions by expressing the mutant mu genes in hybridoma cells which produce the hapten-specific kappa-chain. The normal mu-chain is glycosylated at Asn 402, and, as expected, these mutations appear to abrogate glycosylation of the mutant mu-chains at position 402 and do not affect the hapten affinity of the IgM. However, both of these mutations cause the increased production of monomeric rather than polymeric IgM: the ratio of monomeric to polymeric IgM is 0.21, 3.5, and 10.3 for wild-type IgM, IgM-Gln 402, and IgM-Thr 403-Gly 404, respectively. The wild-type and mutant polymeric IgM preparations were compared for their capacity to promote complement-dependent cytolysis: IgM-Gln 402 and IgM-Thr 403-Gly 404 have approximately 31% and 4%, respectively, of the capacity of wild-type IgM.

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Journal articles on the topic 'IRM structurale'

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