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Sample records for models mimicking human

  1. Mimicking human texture classification

    NARCIS (Netherlands)

    Rogowitz, B.E.; van Rikxoort, Eva M.; van den Broek, Egon; Pappas, T.N.; Schouten, Theo E.; Daly, S.J.

    2005-01-01

    In an attempt to mimic human (colorful) texture classification by a clustering algorithm three lines of research have been encountered, in which as test set 180 texture images (both their color and gray-scale equivalent) were drawn from the OuTex and VisTex databases. First, a k-means algorithm was

  2. Biorelevant media resistant co-culture model mimicking permeability of human intestine.

    Science.gov (United States)

    Antoine, Delphine; Pellequer, Yann; Tempesta, Camille; Lorscheidt, Stefan; Kettel, Bernadette; Tamaddon, Lana; Jannin, Vincent; Demarne, Frédéric; Lamprecht, Alf; Béduneau, Arnaud

    2015-03-15

    Cell culture models are currently used to predict absorption pattern of new compounds and formulations in the human gastro-intestinal tract (GIT). One major drawback is the lack of relevant apical incubation fluids allowing mimicking luminal conditions in the GIT. Here, we suggest a culture model compatible with biorelevant media, namely Fasted State Simulated Intestinal Fluid (FaSSIF) and Fed State Simulated Intestinal Fluid (FeSSIF). Co-culture was set up from Caco-2 and mucus-secreting HT29-MTX cells using an original seeding procedure. Viability and cytotoxicity assays were performed following incubation of FeSSIF and FaSSIF with co-culture. Influence of biorelevant fluids on paracellular permeability or transporter proteins were also evaluated. Results were compared with Caco-2 and HT29-MTX monocultures. While Caco-2 viability was strongly affected with FeSSIF, no toxic effect was detected for the co-cultures in terms of viability and lactate dehydrogenase release. The addition of FeSSIF to the basolateral compartment of the co-culture induced cytotoxic effects which suggested the apical mucus barrier being cell protective. In contrast to FeSSIF, FaSSIF induced a slight increase of the paracellular transport and both tested media inhibited partially the P-gp-mediated efflux in the co-culture. Additionally, the absorptive transport of propranolol hydrochloride, a lipophilic β-blocker, was strongly affected by biorelevant fluids. This study demonstrated the compatibility of the Caco-2/HT29-MTX model with some of the current biorelevant media. Combining biorelevant intestinal fluids with features such as mucus secretion, adjustable paracellular and P-gp mediated transports, is a step forward to more realistic in-vitro models of the human intestine. Copyright © 2015. Published by Elsevier B.V.

  3. [Establishment of sprouting embryoid body model mimicking early embryonic vasculogenesis in human embryo].

    Science.gov (United States)

    Jiang, Hua; Feng, You-Ji; Xie, Yi; Han, Jin-Lan; Wang, Zack; Chen, Tong

    2008-10-14

    To establish a sprouting embryoid body model mimicking early embryonic vasculogenesis in human embryo. Human embryonic stem were (hESCs) were cultured on the mouse embryo fibroblasts and then were induced to differentiate to form three-dimensional EB. The hEBs were cultured in media containing various angiogenesis-related factors: vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), endostatin, angiostatin, and platelet factor (PF)-4 of different concentrations for 3 days to observe the sprouting of the hEBs. 3, 3, 3', 3'-tetramethylindo-carbocyanine perchlorate labeled acetylated low density lipoprotein (Dil-AcLDL) was added onto the hEBs foe 4 h Immunofluorescence assay was used to observe if Dil-AcLDL was absorbed and if CD31 was expressed so as to determine the existence of embryonic endothelial cells in the sprouting structures. The ideal culturing condition was analyzed. The differentiated EBs formed sprouting structures in the collagen I matrix containing VEGF and FGF. The sprouts among individual EBs were able to link to each other and form vascular network-like structures. In the presence of VEGF and FGF, the sprouts branching from the EBs assimilated Dil-AcLDL, expressed CD31 and formed a 3-dimensional cylindrical organization. The concentrations of growth factors ideally stimulating sprouting growth were 100 ng/ml of VEGF and 50 ng/ml of FGF. The networks among the EBs were abolished by the angiostatin, endostatin, and PF4. The sprouting from hEBs accumulates embryonic endothelial cells and the sprouting network-like structures are indeed endothelial in nature. Inducing of sprouting EBs is an ideal model that mimics early embryonic vasculogenesis in humans.

  4. Novel Rat Model of Repetitive Portal Venous Embolization Mimicking Human Non-Cirrhotic Idiopathic Portal Hypertension

    DEFF Research Database (Denmark)

    Klein, Sabine; Hinüber, Christian; Hittatiya, Kanishka

    2016-01-01

    BACKGROUND: Non-cirrhotic idiopathic portal hypertension (NCIPH) is characterized by splenomegaly, anemia and portal hypertension, while liver function is preserved. However, no animal models have been established yet. This study assessed a rat model of NCIPH and characterized the hemodynamics......, and compared it to human NCIPH. METHODS: Portal pressure (PP) was measured invasively and coloured microspheres were injected in the ileocecal vein in rats. This procedure was performed weekly for 3 weeks (weekly embolization). Rats without and with single embolization served as controls. After four weeks (one...... in the weekly embolization group. Fibrotic markers αSMA and Desmin were upregulated in weekly embolized rats. DISCUSSION: This study establishes a model using repetitive embolization via portal veins, comparable with human NCIPH and may serve to test new therapies....

  5. Novel Rat Model of Repetitive Portal Venous Embolization Mimicking Human Non-Cirrhotic Idiopathic Portal Hypertension.

    Science.gov (United States)

    Klein, Sabine; Hinüber, Christian; Hittatiya, Kanishka; Schierwagen, Robert; Uschner, Frank Erhard; Strassburg, Christian P; Fischer, Hans-Peter; Spengler, Ulrich; Trebicka, Jonel

    2016-01-01

    Non-cirrhotic idiopathic portal hypertension (NCIPH) is characterized by splenomegaly, anemia and portal hypertension, while liver function is preserved. However, no animal models have been established yet. This study assessed a rat model of NCIPH and characterized the hemodynamics, and compared it to human NCIPH. Portal pressure (PP) was measured invasively and coloured microspheres were injected in the ileocecal vein in rats. This procedure was performed weekly for 3 weeks (weekly embolization). Rats without and with single embolization served as controls. After four weeks (one week after last embolization), hemodynamics were investigated, hepatic fibrosis and accumulation of myofibroblasts were analysed. General characteristics, laboratory analyses and liver histology were collected in patients with NCIPH. Weekly embolization induced a hyperdynamic circulation, with increased PP. The mesenteric flow and hepatic hydroxyproline content was significantly higher in weekly embolized compared to single embolized rats (mesenteric flow +54.1%, hydroxyproline +41.7%). Mesenteric blood flow and shunt volumes increased, whereas splanchnic vascular resistance was decreased in the weekly embolization group. Fibrotic markers αSMA and Desmin were upregulated in weekly embolized rats. This study establishes a model using repetitive embolization via portal veins, comparable with human NCIPH and may serve to test new therapies.

  6. Humanlike Robots - Synthetically Mimicking Humans

    Science.gov (United States)

    Bar-Cohen, Yoseph

    2012-01-01

    Nature inspired many inventions and the field of technology that is based on the mimicking or inspiration of nature is widely known as Biomimetics and it is increasingly leading to many new capabilities. There are numerous examples of biomimetic successes including the copying of fins for swimming, and the inspiration of the insects and birds flight. More and more commercial implementations of biomimetics are appearing and behaving lifelike and applications are emerging that are important to our daily life. Making humanlike robots is the ultimate challenge to biomimetics and, for many years, it was considered science fiction, but such robots are becoming an engineering reality. Advances in producing such robot are allowing them to perform impressive functions and tasks. The development of such robots involves addressing many challenges and is raising concerns that are related to fear of their application implications and potential ethical issues. In this paper, the state-of-the-art of humanlike robots, potential applications and challenges will be reviewed.

  7. Human pericyte-endothelial cell interactions in co-culture models mimicking the diabetic retinal microvascular environment.

    Science.gov (United States)

    Tarallo, Sonia; Beltramo, Elena; Berrone, Elena; Porta, Massimo

    2012-12-01

    Pericytes regulate vascular tone, perfusion pressure and endothelial cell (EC) proliferation in capillaries. Thiamine and benfotiamine counteract high glucose-induced damage in vascular cells. We standardized two human retinal pericyte (HRP)/EC co-culture models to mimic the diabetic retinal microvascular environment. We aimed at evaluating the interactions between co-cultured HRP and EC in terms of proliferation/apoptosis and the possible protective role of thiamine and benfotiamine against high glucose-induced damage. EC and HRP were co-cultured in physiological glucose and stable or intermittent high glucose, with or without thiamine/benfotiamine. No-contact model: EC were plated on a porous membrane suspended into the medium and HRP on the bottom of the same well. Cell-to-cell contact model: EC and HRP were plated on the opposite sides of the same membrane. Proliferation (cell counts and DNA synthesis), apoptosis and tubule formation in Matrigel were assessed. In the no-contact model, stable high glucose reduced proliferation of co-cultured EC/HRP and EC alone and increased co-cultured EC/HRP apoptosis. In the contact model, both stable and intermittent high glucose reduced co-cultured EC/HRP proliferation and increased apoptosis. Stable high glucose had no effects on HRP in separate cultures. Both EC and HRP proliferated better when co-cultured. Thiamine and benfotiamine reversed high glucose-induced damage in all cases. HRP are sensitive to soluble factors released by EC when cultured in high glucose conditions, as suggested by conditioned media assays. In the Matrigel models, addition of thiamine and benfotiamine re-established the high glucose-damaged interactions between EC/HRP and stabilized microtubules.

  8. KRAS (G12D Cooperates with AML1/ETO to Initiate a Mouse Model Mimicking Human Acute Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Shanmin Zhao

    2014-01-01

    Full Text Available Background/Aims: It has been demonstrated that KRAS mutations represent about 90% of cancer-associated mutations, and that KRAS mutations play an essential role in neoplastic transformation. Cancer-associated RAS mutations occur frequently in acute myeloid leukemia (AML, suggesting a functional role for Ras in leukemogenesis. Methods: We successfully established a mouse model of human leukemia by transplanting bone marrow cells co-transfected with the K-ras (G12D mutation and AML1/ETO fusion protein. Results: Mice transplanted with AML/ETO+KRAS co-transduced cells had the highest mortality rate than mice transplanted with AML/ETO- or KRAS-transduced cells (115d vs. 150d. Upon reaching a terminal disease stage, EGFP-positive cells dominated their spleen, lymph nodes, peripheral blood and central nervous system tissue. Immunophenotyping, cytologic analyses revealed that AML/ETO+KRAS leukemias predominantly contained immature myeloid precursors (EGFP+/c-Kit+/Mac-1-/Gr-1-. Histologic analyses revealed that massive leukemic infiltrations were closely packed in dense sheets that effaced the normal architecture of spleen and thymus in mice transplanted with AML1/ETO + KRAS co-transduced cells. K-ras mRNA and protein expression were upregulated in bone marrow cells of the K-ras group and AML1/ETO + Kras group. The phosphorylation of MEK/ERK was significantly enhanced in the AML1/ETO + Kras group. The similar results of the AML1/ETO + Nras group were consistent with those reported previously. Conclusion: Co-transduction of KrasG12D and AML1/ETO induces acute monoblastic leukemia. Since expression of mutant K-ras alone was insufficient to induce leukemia, this model may be useful for investigating the multi-step leukemogenesis model of human leukemia.

  9. Human in vitro 3D co-culture model to engineer vascularized bone-mimicking tissues combining computational tools and statistical experimental approach.

    Science.gov (United States)

    Bersini, Simone; Gilardi, Mara; Arrigoni, Chiara; Talò, Giuseppe; Zamai, Moreno; Zagra, Luigi; Caiolfa, Valeria; Moretti, Matteo

    2016-01-01

    The generation of functional, vascularized tissues is a key challenge for both tissue engineering applications and the development of advanced in vitro models analyzing interactions among circulating cells, endothelium and organ-specific microenvironments. Since vascularization is a complex process guided by multiple synergic factors, it is critical to analyze the specific role that different experimental parameters play in the generation of physiological tissues. Our goals were to design a novel meso-scale model bridging the gap between microfluidic and macro-scale studies, and high-throughput screen the effects of multiple variables on the vascularization of bone-mimicking tissues. We investigated the influence of endothelial cell (EC) density (3-5 Mcells/ml), cell ratio among ECs, mesenchymal stem cells (MSCs) and osteo-differentiated MSCs (1:1:0, 10:1:0, 10:1:1), culture medium (endothelial, endothelial + angiopoietin-1, 1:1 endothelial/osteo), hydrogel type (100%fibrin, 60%fibrin+40%collagen), tissue geometry (2 × 2 × 2, 2 × 2 × 5 mm(3)). We optimized the geometry and oxygen gradient inside hydrogels through computational simulations and we analyzed microvascular network features including total network length/area and vascular branch number/length. Particularly, we employed the "Design of Experiment" statistical approach to identify key differences among experimental conditions. We combined the generation of 3D functional tissue units with the fine control over the local microenvironment (e.g. oxygen gradients), and developed an effective strategy to enable the high-throughput screening of multiple experimental parameters. Our approach allowed to identify synergic correlations among critical parameters driving microvascular network development within a bone-mimicking environment and could be translated to any vascularized tissue. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Mimicking the LCDM model with stealths

    Energy Technology Data Exchange (ETDEWEB)

    Campuzano, Cuauhtemoc [Universidad Veracruzana, Facultad de Fisica, Xalapa, Veracruz (Mexico); Cardenas, Victor H. [Universidad de Valparaiso, Facultad de Ciencias, Instituto de Fisica y Astronomia, Valparaiso (Chile); Herrera, Ramon [Pontificia Universidad Catolica de Valparaiso, Instituto de Fisica, Avenida Brasil 2950, Casilla 4059, Valparaiso (Chile)

    2016-12-15

    We present a new cosmological model that mimics the Lambda Cold Dark Matter by using a stealth field. This kind of field is characterized as not coupling directly to gravity; however, it is connected to the underlying matter content of the universe model. As is well known, stealth fields do not back-react on the space-time; however, their mimicry skills show how this field and its self-interaction potential determines the cosmic evolution. We show the study of the simplest model that can be developed with the stealth field. (orig.)

  11. M-HinTS: Mimicking Humans in Texture Sorting

    NARCIS (Netherlands)

    van den Broek, Egon; Rogowitz, Bernice E.; van Rikxoort, Eva M.; Pappas, Thrasyvoulos N.; Kok, Thijs; Daly, Scott J.; Schouten, Theo E.

    2006-01-01

    Various texture analysis algorithms have been developed the last decades. However, no computational model has arisen that mimics human texture perception adequately. In 2000, Payne, Hepplewhite, and Stoneham and in 2005, Van Rikxoort, Van den Broek, and Schouten achieved mappings between humans and

  12. Interaction of a peptide derived from C-terminus of human TRPA1 channel with model membranes mimicking the inner leaflet of the plasma membrane.

    Science.gov (United States)

    Witschas, Katja; Jobin, Marie-Lise; Korkut, Dursun Nizam; Vladan, Maria Magdalena; Salgado, Gilmar; Lecomte, Sophie; Vlachova, Viktorie; Alves, Isabel D

    2015-05-01

    The transient receptor potential ankyrin 1 channel (TRPA1) belongs to the TRP cation channel superfamily that responds to a panoply of stimuli such as changes in temperature, calcium levels, reactive oxygen and nitrogen species and lipid mediators among others. The TRP superfamily has been implicated in diverse pathological states including neurodegenerative disorders, kidney diseases, inflammation, pain and cancer. The intracellular C-terminus is an important regulator of TRP channel activity. Studies with this and other TRP superfamily members have shown that the C-terminus association with lipid bilayer alters channel sensitivity and activation, especially interactions occurring through basic residues. Nevertheless, it is not yet clear how this process takes place and which regions in the C-terminus would be responsible for such membrane recognition. With that in mind, herein the first putative membrane interacting region of the C-terminus of human TRPA1, (corresponding to a 29 residue peptide, IAEVQKHASLKRIAMQVELHTSLEKKLPL) named H1 due to its potential helical character was chosen for studies of membrane interaction. The affinity of H1 to lipid membranes, H1 structural changes occurring upon this interaction as well as effects of this interaction in lipid organization and integrity were investigated using a biophysical approach. Lipid models systems composed of zwitterionic and anionic lipids, namely those present in the lipid membrane inner leaflet, where H1 is prone to interact, where used. The study reveals a strong interaction and affinity of H1 as well as peptide structuration especially with membranes containing anionic lipids. Moreover, the interactions and peptide structure adoption are headgroup specific. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. A New Mouse Model of Limb-Girdle Muscular Dystrophy Type 2I Homozygous for the Common L276I Mutation Mimicking the Mild Phenotype in Humans

    DEFF Research Database (Denmark)

    Krag, Thomas O; Vissing, John

    2015-01-01

    Limb-girdle muscular dystrophy type 2I (LGMD2I) is caused by mutations in the Fukutin-related protein (FKRP) gene, leading to inadequate glycosylation of α-dystroglycan, an important protein linking the extracellular matrix to the cytoskeleton. We created a mouse model of the common FKRP L276I...... mutation and a hemizygous FKRP L276I knockout model. We studied histopathology and protein expression in the models at different ages and found that homozygous FKRP L276I mice developed a mild progressive myopathy with increased muscle regeneration and fibrosis starting from 1 year of age. This was likely...... in maintaining proper glycosylation of α-dystroglycan. The mild progression in the homozygous FKRP L276I model resembles that in patients with LGMD2I who are homozygous for the L276I mutation. This animal model could, therefore, be relevant for understanding the pathophysiology of and developing a treatment...

  14. Deriving a blood-mimicking fluid for particle image velocimetry in Sylgard-184 vascular models.

    Science.gov (United States)

    Yousif, Majid Y; Holdsworth, David W; Poepping, Tamie L

    2009-01-01

    A new blood-mimicking fluid (BMF) has been developed for particle image velocimetry (PIV), which enables flow studies in vascular models (phantoms). A major difficulty in PIV that affects measurement accuracy is the refraction and distortion of light passing through the interface between the model and the fluid, due to the difference in refractive index (n) between the two materials. The problem can be eliminated by using a fluid with a refractive index matching that of the model. Such fluids are not commonly available, especially for vascular research where the fluid should also have a viscosity similar to human blood. In this work, a blood-mimicking fluid, composed of water (47.38% by weight), glycerol (36.94% by weight) and sodium iodide salt (15.68% by weight), was developed for compatibility with our silicone (Sylgard 184; n = 1.414) phantoms. The fluid exhibits a dynamic viscosity of 4.31+/-0.03 cP which lies within the range of human blood viscosity (4.4+/-0.6 cP). Both refractive index and viscosity were attained at 22.2+/-0.2 degrees C, which is a feasible room temperature, thus eliminating the need for a temperature-control system. The fluid will be used to study hemodynamics in vascular flow models fabricated from Sylgard 184.

  15. Humans mimicking animals: A cortical hierarchy for human vocal communication sounds

    Science.gov (United States)

    Talkington, William J.; Rapuano, Kristina M.; Hitt, Laura; Frum, Chris A.; Lewis, James W.

    2012-01-01

    Numerous species possess cortical regions that are most sensitive to vocalizations produced by their own kind (conspecifics). In humans, the superior temporal sulci (STS) putatively represent homologous voice-sensitive areas of cortex. However, STS regions have recently been reported to represent auditory experience or “expertise” in general rather than showing exclusive sensitivity to human vocalizations per se. Using functional magnetic resonance imaging and a unique non-stereotypical category of complex human non-verbal vocalizations – human-mimicked versions of animal vocalizations – we found a cortical hierarchy in humans optimized for processing meaningful conspecific utterances. This left-lateralized hierarchy originated near primary auditory cortices and progressed into traditional speech-sensitive areas. These results suggest that the cortical regions supporting vocalization perception are initially organized by sensitivity to the human vocal tract in stages prior to the STS. Additionally, these findings have implications for the developmental time course of conspecific vocalization processing in humans as well as its evolutionary origins. PMID:22674283

  16. Developing Autonomous Vehicles That Learn to Navigate by Mimicking Human Behavior

    Science.gov (United States)

    2006-09-28

    navigate in an unstructured environment to a specific target or location. 15. SUBJECT TERMS autonomous vehicles , fuzzy logic, learning behavior...ANSI-Std Z39-18 Developing Autonomous Vehicles That Learn to Navigate by Mimicking Human Behavior FINAL REPORT 9/28/2006 Dean B. Edwards Department...the future, as greater numbers of autonomous vehicles are employed, it is hoped that lower LONG-TERM GOALS Use LAGR (Learning Applied to Ground Robots

  17. Congruent strain specific intestinal persistence of Lactobacillus plantarum in an intestine-mimicking in vitro system and in human volunteers.

    Directory of Open Access Journals (Sweden)

    Hermien van Bokhorst-van de Veen

    Full Text Available BACKGROUND: An important trait of probiotics is their capability to reach their intestinal target sites alive to optimally exert their beneficial effects. Assessment of this trait in intestine-mimicking in vitro model systems has revealed differential survival of individual strains of a species. However, data on the in situ persistence characteristics of individual or mixtures of strains of the same species in the gastrointestinal tract of healthy human volunteers have not been reported to date. METHODOLOGY/PRINCIPAL FINDINGS: The GI-tract survival of individual L. plantarum strains was determined using an intestine mimicking model system, revealing substantial inter-strain differences. The obtained data were correlated to genomic diversity of the strains using comparative genome hybridization (CGH datasets, but this approach failed to discover specific genetic loci that explain the observed differences between the strains. Moreover, we developed a next-generation sequencing-based method that targets a variable intergenic region, and employed this method to assess the in vivo GI-tract persistence of different L. plantarum strains when administered in mixtures to healthy human volunteers. Remarkable consistency of the strain-specific persistence curves were observed between individual volunteers, which also correlated significantly with the GI-tract survival predicted on basis of the in vitro assay. CONCLUSION: The survival of individual L. plantarum strains in the GI-tract could not be correlated to the absence or presence of specific genes compared to the reference strain L. plantarum WCFS1. Nevertheless, in vivo persistence analysis in the human GI-tract confirmed the strain-specific persistence, which appeared to be remarkably similar in different healthy volunteers. Moreover, the relative strain-specific persistence in vivo appeared to be accurately and significantly predicted by their relative survival in the intestine-mimicking in vitro

  18. Automatic ECG quality scoring methodology: mimicking human annotators

    International Nuclear Information System (INIS)

    Johannesen, Lars; Galeotti, Loriano

    2012-01-01

    An algorithm to determine the quality of electrocardiograms (ECGs) can enable inexperienced nurses and paramedics to record ECGs of sufficient diagnostic quality. Previously, we proposed an algorithm for determining if ECG recordings are of acceptable quality, which was entered in the PhysioNet Challenge 2011. In the present work, we propose an improved two-step algorithm, which first rejects ECGs with macroscopic errors (signal absent, large voltage shifts or saturation) and subsequently quantifies the noise (baseline, powerline or muscular noise) on a continuous scale. The performance of the improved algorithm was evaluated using the PhysioNet Challenge database (1500 ECGs rated by humans for signal quality). We achieved a classification accuracy of 92.3% on the training set and 90.0% on the test set. The improved algorithm is capable of detecting ECGs with macroscopic errors and giving the user a score of the overall quality. This allows the user to assess the degree of noise and decide if it is acceptable depending on the purpose of the recording. (paper)

  19. Non-dermatophyte Dermatoses Mimicking Dermatophytoses in Humans.

    Science.gov (United States)

    Libon, F; Nikkels-Tassoudji, N; Dezfoulian, B; Arrese, J E; Nikkels, A F

    2017-02-01

    Human dermatophytic cutaneous infections usually present as single or multiple slowly progressing annular erythemato-squamous lesions with a tendency to central healing on the hairless skin. In the intertriginous regions (feet, inguinal, axillar, submammary), dermatophytic colonisations and infections manifest as whitish, slightly hyperkeratotic, pruritic and sometimes fissurated lesions. On the scalp, dermatophytic infections commonly lead to single or multiple more or less inflammatory and alopecic lesions. On the plantar and palmar aspects of the feet and hand, dermatophytosis presents as an eczema-like chronic dermatosis. Abscess-like lesions may occur due to zoophilic dermatomycosis. Dermatophytic infections of the nails reveal ill-defined whitish-yellowish colorations of the distal end or the lateral aspects of the nails, sometimes combined with partial nail embrittlement or even complete destruction. Despite the ubiquity of dermatophytic skin infections and their usually highly typical clinical features, a differential diagnosis has to be considered, in particular when treatment is not efficient or when treatment resistance occurs. This review presents the differential diagnosis in terms of frequency as well as the diagnostic methods permitting the distinction of annular, intertriginous, alopecic, palmoplantar, abscess-like and onychodystrophic lesions.

  20. A blood-mimicking fluid for particle image velocimetry with silicone vascular models

    Science.gov (United States)

    Yousif, Majid Y.; Holdsworth, David W.; Poepping, Tamie L.

    2011-03-01

    For accurate particle image velocimetry measurements in hemodynamics studies, it is important to use a fluid with a refractive index ( n) matching that of the vascular models (phantoms) and ideally a dynamic viscosity matching human blood. In this work, a blood-mimicking fluid (BMF) composed of water, glycerol, and sodium iodide was formulated for a range of refractive indices to match most common silicone elastomers ( n = 1.40-1.43) and with corresponding dynamic viscosity within the average cited range of healthy human blood (4.4 ± 0.5 cP). Both refractive index and viscosity were attained at room temperature (22.2 ± 0.2°C), which eliminates the need for a temperature-control system. An optimally matched BMF, suitable for use in a vascular phantom ( n = 1.4140 ± 0.0008, Sylgard 184), was demonstrated with composition (by weight) of 47.38% water, 36.94% glycerol (44:56 glycerol-water ratio), and 15.68% sodium iodide salt, resulting in a dynamic viscosity of 4 .31 ± 0 .03 cP.

  1. MRI-based morphological modeling, synthesis and characterization of cardiac tissue-mimicking materials.

    Science.gov (United States)

    Kossivas, Fotis; Angeli, S; Kafouris, D; Patrickios, C S; Tzagarakis, V; Constantinides, C

    2012-06-01

    This study uses standard synthetic methodologies to produce tissue-mimicking materials that match the morphology and emulate the in vivo murine and human cardiac mechanical and imaging characteristics, with dynamic mechanical analysis, atomic force microscopy (AFM), scanning electron microscopy (SEM) and magnetic resonance imaging. In accordance with such aims, poly(glycerol sebacate) (PGS) elastomeric materials were synthesized (at two different glycerol (G)-sebacic (S) acid molar ratios; the first was synthesized using a G:S molar ratio of 2:2, while the second from a 2:5 G:S molar ratio, resulting in PGS2:2 and PGS2:5 elastomers, respectively). Unlike the synthesized PGS2:2 elastomers, the PGS2:5 materials were characterized by an overall mechanical instability in their loading behavior under the three successive loading conditions tested. An oscillatory response in the mechanical properties of the synthesized elastomers was observed throughout the loading cycles, with measured increased storage modulus values at the first loading cycle, stabilizing to lower values at subsequent cycles. These elastomers were characterized at 4 °C and were found to have storage modulus values of 850 and 1430 kPa at the third loading cycle, respectively, in agreement with previously reported values of the rat and human myocardium. SEM of surface topology indicated minor degradation of synthesized materials at 10 and 20 d post-immersion in the PBS buffer solution, with a noted cluster formation on the PGS2:5 elastomers. AFM nanoindentation experiments were also conducted for the measurement of the Young modulus of the sample surface (no bulk contribution). Correspondingly, the PGS2:2 elastomer indicated significantly decreased surface Young's modulus values 20 d post-PBS immersion, compared to dry conditions (Young's modulus = 1160 ± 290 kPa (dry) and 200 ± 120 kPa (20 d)). In addition to the two-dimensional (2D) elastomers, an integrative platform for accurate construction of

  2. MRI-based morphological modeling, synthesis and characterization of cardiac tissue-mimicking materials

    International Nuclear Information System (INIS)

    Kossivas, Fotis; Angeli, S; Constantinides, C; Kafouris, D; Patrickios, C S; Tzagarakis, V

    2012-01-01

    This study uses standard synthetic methodologies to produce tissue-mimicking materials that match the morphology and emulate the in vivo murine and human cardiac mechanical and imaging characteristics, with dynamic mechanical analysis, atomic force microscopy (AFM), scanning electron microscopy (SEM) and magnetic resonance imaging. In accordance with such aims, poly(glycerol sebacate) (PGS) elastomeric materials were synthesized (at two different glycerol (G)–sebacic (S) acid molar ratios; the first was synthesized using a G:S molar ratio of 2:2, while the second from a 2:5 G:S molar ratio, resulting in PGS2:2 and PGS2:5 elastomers, respectively). Unlike the synthesized PGS2:2 elastomers, the PGS2:5 materials were characterized by an overall mechanical instability in their loading behavior under the three successive loading conditions tested. An oscillatory response in the mechanical properties of the synthesized elastomers was observed throughout the loading cycles, with measured increased storage modulus values at the first loading cycle, stabilizing to lower values at subsequent cycles. These elastomers were characterized at 4 °C and were found to have storage modulus values of 850 and 1430 kPa at the third loading cycle, respectively, in agreement with previously reported values of the rat and human myocardium. SEM of surface topology indicated minor degradation of synthesized materials at 10 and 20 d post-immersion in the PBS buffer solution, with a noted cluster formation on the PGS2:5 elastomers. AFM nanoindentation experiments were also conducted for the measurement of the Young modulus of the sample surface (no bulk contribution). Correspondingly, the PGS2:2 elastomer indicated significantly decreased surface Young's modulus values 20 d post-PBS immersion, compared to dry conditions (Young's modulus = 1160 ± 290 kPa (dry) and 200 ± 120 kPa (20 d)). In addition to the two-dimensional (2D) elastomers, an integrative platform for accurate construction of

  3. A heterogeneous human tissue mimicking phantom for RF heating and MRI thermal monitoring verification.

    Science.gov (United States)

    Yuan, Yu; Wyatt, Cory; Maccarini, Paolo; Stauffer, Paul; Craciunescu, Oana; Macfall, James; Dewhirst, Mark; Das, Shiva K

    2012-04-07

    This paper describes a heterogeneous phantom that mimics a human thigh with a deep-seated tumor, for the purpose of studying the performance of radiofrequency (RF) heating equipment and non-invasive temperature monitoring with magnetic resonance imaging (MRI). The heterogeneous cylindrical phantom was constructed with an outer fat layer surrounding an inner core of phantom material mimicking muscle, tumor and marrow-filled bone. The component materials were formulated to have dielectric and thermal properties similar to human tissues. The dielectric properties of the tissue mimicking phantom materials were measured with a microwave vector network analyzer and impedance probe over the frequency range of 80-500 MHz and at temperatures of 24, 37 and 45 °C. The specific heat values of the component materials were measured using a differential scanning calorimeter over the temperature range of 15-55 °C. The thermal conductivity value was obtained from fitting the curves obtained from one-dimensional heat transfer measurement. The phantom was used to verify the operation of a cylindrical four-antenna annular phased array extremity applicator (140 MHz) by examining the proton resonance frequency shift (PRFS) thermal imaging patterns for various magnitude/phase settings (including settings to focus heating in tumors). For muscle and tumor materials, MRI was also used to measure T1/T2* values (1.5 T) and to obtain the slope of the PRFS phase change versus temperature change curve. The dielectric and thermal properties of the phantom materials were in close agreement to well-accepted published results for human tissues. The phantom was able to successfully demonstrate satisfactory operation of the tested heating equipment. The MRI-measured thermal distributions matched the expected patterns for various magnitude/phase settings of the applicator, allowing the phantom to be used as a quality assurance tool. Importantly, the material formulations for the various tissue types

  4. Full experimental modelling of a liver tissue mimicking phantom for medical ultrasound studies employing different hydrogels.

    Science.gov (United States)

    Casciaro, Sergio; Conversano, Francesco; Musio, Stefano; Casciaro, Ernesto; Demitri, Christian; Sannino, Alessandro

    2009-04-01

    Tissue mimicking phantoms have been widely reported to be an important tool for development, optimisation and performance testing of ultrasound-based diagnostic techniques. In particular, modern applications of tissue mimicking phantoms often include characterisation of the nonlinear behaviour of experimental ultrasound contrast agents. In such cases, the tissue-mimicking materials should be chosen not only based on the values of their density, speed of sound and attenuation coefficient, but also considering their effect on the appearance of "native harmonics" due to nonlinear distortion of ultrasound signal during propagation. In a previous paper it was demonstrated that a cellulose-based hydrogel is suitable to simulate nonlinear acoustical behaviour of liver tissue for thicknesses up to 8 cm. In this paper we present the experimental characterisation of the nonlinear acoustical behaviour of a different polyethylene glycol diacrylate (PEGDA)-based hydrogel, in order to assess whether and how it can improve the performances and overcome some limitations of the cellulose-based hydrogel as liver tissue-mimicking material. Samples of pig liver tissue, cellulose-based hydrogel and PEGDA-based hydrogel were insonified in a through-transmission set-up, employing 2.25-MHz pulses with different mechanical index (MI) values. Second harmonic and first harmonic amplitudes were extracted from the spectra of received signals and their difference was then used to compare sample behaviours. Obtained results show how a new more accurate and combined experimental model of linear and nonlinear acoustical behaviour of liver tissue is feasible. In fact, a further confirmation of the cellulose-based hydrogel effectiveness to precisely simulate the liver tissue for penetration depths up to 8 cm was provided, and it was also shown that the employment of the PEGDA-based hydrogel can extend the range of useful tissue-mimicking material thicknesses up to 11 cm, moreover allowing a

  5. Congruent Strain Specific Intestinal Persistence of Lactobacillus plantarum in an Intestine-Mimicking In Vitro System and in Human Volunteers.

    NARCIS (Netherlands)

    Bokhorst-van de Veen, H. van; Swam, I. van; Wels, M.W.; Bron, P.A.; Kleerebezem, M

    2012-01-01

    BACKGROUND: An important trait of probiotics is their capability to reach their intestinal target sites alive to optimally exert their beneficial effects. Assessment of this trait in intestine-mimicking in vitro model systems has revealed differential survival of individual strains of a species.

  6. Congruent Strain Specific Intestinal Persistence of Lactobacillus plantarum in an Intestine-Mimicking In Vitro System and in Human Volunteers

    NARCIS (Netherlands)

    Bokhorst-van de Veen, van H.; Swam, van I.; Wels, M.; Bron, P.A.; Kleerebezem, M.

    2012-01-01

    BACKGROUND: An important trait of probiotics is their capability to reach their intestinal target sites alive to optimally exert their beneficial effects. Assessment of this trait in intestine-mimicking in vitro model systems has revealed differential survival of individual strains of a species.

  7. Human immunodeficiency virus-positive secondary syphilis mimicking cutaneous T-cell lymphoma.

    Science.gov (United States)

    Yamashita, Michiko; Fujii, Yoshiyuki; Ozaki, Keiji; Urano, Yoshio; Iwasa, Masami; Nakamura, Shingen; Fujii, Shiro; Abe, Masahiro; Sato, Yasuharu; Yoshino, Tadashi

    2015-10-08

    Malignant syphilis or lues maligna is a severe form of secondary syphilis that was commonly reported in the pre-antibiotic era, and has now reemerged with the advent of the human immunodeficiency virus (HIV) epidemic. However, the characteristic histopathological findings of malignant syphilis remain controversial. The aim of this case report was to clarify the clinical and histopathological findings of HIV-positive malignant secondary syphilis. A Japanese man in his forties complained of fever, skin lesions, headache, and myalgia without lymphadenopathy during the previous 4 weeks. The skin lesions manifested as erythematous, nonhealing, ulcerated papules scattered on his trunk, extremities, palm, and face. Although the skin lesions were suspected to be cutaneous T-cell lymphomas on histological analyses, they lacked T-cell receptor Jγ rearrangement; moreover, immunohistochemical analyses confirmed the presence of spirochetes. The patient was administered antibiotics and anti-retroviral therapy, which dramatically improved the symptoms. On the basis of these observations of the skin lesions, we finally diagnosed the patient with HIV-associated secondary syphilis that mimicked cutaneous T-cell lymphoma. The patient's systemic CD4+ lymphocyte count was very low, and the infiltrate was almost exclusively composed of CD8+ atypical lymphocytes; therefore, the condition was easily misdiagnosed as cutaneous lymphoma. Although the abundance of plasma cells is a good indicator of malignant syphilis on skin histological analyses, in some cases, the plasma cell count may be very low. Therefore, a diagnosis of malignant secondary syphilis should be considered before making a diagnosis of primary cutaneous peripheral T-cell lymphoma or lymphoma associated with HIV infection.

  8. Proposed Pharmacological Countermeasures Against Apoptotic Cell Death in Experimental Models Mimicking Space Environment Damage

    Science.gov (United States)

    Lulli, Matteo; Papucci, Laura; Witort, Ewa; Donnini, Martino; Lapucci, Andrea; Lazzarano, Stefano; Mazzoni, Tiziano; Simoncini, Madine; Falciani, Piergiuseppe; Capaccioli, Sergio

    2008-06-01

    Several damaging agents have been suggested to affect human vision during long term space travels. Recently, apoptosis induced by DNA-damaging agents has emerged as frequent pathogenetic mechanism of ophthalmologic pathologies. Here, we propose two countermeasures: coenzyme Q10 and bcl-2 downregulation preventing antisense oligoribonucleotides (ORNs), aimed to inhibit cellular apoptotic death. Our studies have been carried out on retina and neuronal cultured cells treated with the following apoptotic stimuli mimicking space environment: a several-day exposure to either 3H-labeled tymidine or to the genotoxic drug doxorubicin, UV irradiation, hypoxia and glucose/growth factor starvation (Locke medium). The preliminary results clearly indicate that CoQ10, as well as bcl-2 down-regulation preventing ORNs, significantly counteract apoptosis in response to different DNA damaging agents in cultured eye and in neuronal cells. This supports the possibility that both could be optimal countermeasures against ophthalmologic lesions during space explorations.

  9. Human stem cell based corneal tissue mimicking structures using laser-assisted 3D bioprinting and functional bioinks.

    Science.gov (United States)

    Sorkio, Anni; Koch, Lothar; Koivusalo, Laura; Deiwick, Andrea; Miettinen, Susanna; Chichkov, Boris; Skottman, Heli

    2018-07-01

    There is a high demand for developing methods to produce more native-like 3D corneal structures. In the present study, we produced 3D cornea-mimicking tissues using human stem cells and laser-assisted bioprinting (LaBP). Human embryonic stem cell derived limbal epithelial stem cells (hESC-LESC) were used as a cell source for printing epithelium-mimicking structures, whereas human adipose tissue derived stem cells (hASCs) were used for constructing layered stroma-mimicking structures. The development and optimization of functional bioinks was a crucial step towards successful bioprinting of 3D corneal structures. Recombinant human laminin and human sourced collagen I served as the bases for the functional bioinks. We used two previously established LaBP setups based on laser induced forward transfer, with different laser wavelengths and appropriate absorption layers. We bioprinted three types of corneal structures: stratified corneal epithelium using hESC-LESCs, lamellar corneal stroma using alternating acellular layers of bioink and layers with hASCs, and finally structures with both a stromal and epithelial part. The printed constructs were evaluated for their microstructure, cell viability and proliferation, and key protein expression (Ki67, p63α, p40, CK3, CK15, collagen type I, VWF). The 3D printed stromal constructs were also implanted into porcine corneal organ cultures. Both cell types maintained good viability after printing. Laser-printed hESC-LESCs showed epithelial cell morphology, expression of Ki67 proliferation marker and co-expression of corneal progenitor markers p63α and p40. Importantly, the printed hESC-LESCs formed a stratified epithelium with apical expression of CK3 and basal expression of the progenitor markers. The structure of the 3D bioprinted stroma demonstrated that the hASCs had organized horizontally as in the native corneal stroma and showed positive labeling for collagen I. After 7 days in porcine organ cultures, the 3D bioprinted

  10. Model of the Phase Transition Mimicking the Pasta Phase in Cold and Dense Quark-Hadron Matter

    Science.gov (United States)

    Ayriyan, Alexander; Grigorian, Hovik

    2018-02-01

    A simple mixed phase model mimicking so-called "pasta" phases in the quarkhadron phase transition is developed and applied to static neutron stars for the case of DD2 type hadronic and NJL type quark matter models. The influence of the mixed phase on the mass-radius relation of the compact stars is investigated. Model parameters are chosen such that the results are in agreement with the mass-radius constraints.

  11. A rabbit model of fatal hypothyroidism mimicking "myxedema coma" established by microscopic total thyroidectomy.

    Science.gov (United States)

    Ono, Yosuke; Fujita, Masanori; Ono, Sachiko; Ogata, Sho; Tachibana, Shoichi; Tanaka, Yuji

    2016-06-30

    Myxedema coma (MC) is a life-threatening endocrine crisis caused by severe hypothyroidism. However, validated diagnostic criteria and treatment guidelines for MC have not been established owing to its rarity. Therefore, a valid animal model is required to investigate the pathologic and therapeutic aspects of MC. The aim of the present study was to establish an animal model of MC induced by total thyroidectomy. We utilized 14 male New Zealand White rabbits anesthetized via intramuscular ketamine and xylazine administration. A total of 7 rabbits were completely thyroidectomized under a surgical microscope (thyroidectomized group) and the remainder underwent sham operations (control group). The animals in both groups were monitored without thyroid hormone replacement for 15 weeks. Pulse rate, blood pressure, body temperature, and electrocardiograms (ECG) were recorded and blood samples were taken from the jugular vein immediately prior to the thyroidectomy and 2 and 4 weeks after surgery. The thyroidectomized rabbits showed a marked reduction of serum thyroxine levels at 4 weeks after the surgical procedure vs. controls (0.50±0.10 vs. 3.32±0.68 μg/dL, pmyxedema heart. In summary, we have established a rabbit model of fatal hypothyroidism mimicking MC, which may facilitate pathophysiological and molecular investigations of MC and evaluations of new therapeutic interventions.

  12. Immunogenic multistage recombinant protein vaccine confers partial protection against experimental toxoplasmosis mimicking natural infection in murine model

    Directory of Open Access Journals (Sweden)

    Yaprak Gedik

    2016-01-01

    To generate a protective vaccine against toxoplasmosis, multistage vaccines and usage of challenging models mimicking natural route of infection are critical cornerstones. In this study, we generated a BAG1 and GRA1 multistage vaccine that induced strong immune response in which the protection was not at anticipated level. In addition, the murine model was orally challenged with tissue cysts to mimic natural route of infection.

  13. Imparting albumin-binding affinity to a human protein by mimicking the contact surface of a bacterial binding protein.

    Science.gov (United States)

    Oshiro, Satoshi; Honda, Shinya

    2014-04-18

    Attachment of a bacterial albumin-binding protein module is an attractive strategy for extending the plasma residence time of protein therapeutics. However, a protein fused with such a bacterial module could induce unfavorable immune reactions. To address this, we designed an alternative binding protein by imparting albumin-binding affinity to a human protein using molecular surface grafting. The result was a series of human-derived 6 helix-bundle proteins, one of which specifically binds to human serum albumin (HSA) with adequate affinity (KD = 100 nM). The proteins were designed by transferring key binding residues of a bacterial albumin-binding module, Finegoldia magna protein G-related albumin-binding domain (GA) module, onto the human protein scaffold. Despite 13-15 mutations, the designed proteins maintain the original secondary structure by virtue of careful grafting based on structural informatics. Competitive binding assays and thermodynamic analyses of the best binders show that the binding mode resembles that of the GA module, suggesting that the contacting surface of the GA module is mimicked well on the designed protein. These results indicate that the designed protein may act as an alternative low-risk binding module to HSA. Furthermore, molecular surface grafting in combination with structural informatics is an effective approach for avoiding deleterious mutations on a target protein and for imparting the binding function of one protein onto another.

  14. Human herpesvirus 8-associated lymphoma mimicking cutaneous anaplastic large T-cell lymphoma in a patient with human immunodeficiency virus infection.

    Science.gov (United States)

    Li, Meng-Fang; Hsiao, Cheng-Hsiang; Chen, Yi-Lin; Huang, Wen-Ya; Lee, Yi-Hsuan; Huang, Hsien-Neng; Lien, Huang-Chun

    2012-02-01

    Primary effusion lymphoma, a human herpesvirus 8 (HHV8)-associated lymphoma, is uncommon, and it is usually seen in human immunodeficiency virus (HIV)-infected patients. It presents as a body cavity-based lymphomatous effusion, but several cases of the so-called solid primary effusion lymphoma presenting as solid tumors without associated lymphomatous effusion have been reported. They have similar clinical, histopathological and immunophenotypical features. Most of them have a B-cell genotype. This suggests the solid variant may represent a clinicopathological spectrum of primary effusion lymphoma. We report a case of HHV8-associated lymphoma histopathologically and immunophenotypically mimicking cutaneous anaplastic large cell lymphoma. The patient was a 31-year-old HIV-seropositive man presenting with skin nodules over his right thigh. Biopsy of the nodules showed anaplastic large cells infiltrating the dermis. These malignant cells strongly expressed CD3, CD30 and CD43. Cutaneous anaplastic large T-cell lymphoma was initially diagnosed, but further tests, including immunoreactivity for HHV8 protein and clonal rearrangements of immunoglobulin genes, confirmed the diagnosis of HHV8-associated B-cell lymphoma with aberrant T-cell marker expression. This case provides an example of solid primary effusion lymphoma mimicking cutaneous anaplastic large T-cell lymphoma and highlights the importance of HHV8 immunohistochemistry and molecular tests in the diagnosis of HHV8-associated lymphoma with a cutaneous presentation. Copyright © 2011 John Wiley & Sons A/S.

  15. Enhancing fuzzy robot navigation systems by mimicking human visual perception of natural terrain traversibility

    Science.gov (United States)

    Tunstel, E.; Howard, A.; Edwards, D.; Carlson, A.

    2001-01-01

    This paper presents a technique for learning to assess terrain traversability for outdoor mobile robot navigation using human-embedded logic and real-time perception of terrain features extracted from image data.

  16. Human brucellosis mimicking axial spondyloarthritis: a challenge for rheumatologists when applying the 2009 ASAS criteria.

    Science.gov (United States)

    Ye, Cong; Shen, Gui-Fen; Li, Shou-Xin; Dong, Ling-Li; Yu, Yi-Kai; Tu, Wei; Zhu, Ying-Zi; Hu, Shao-Xian

    2016-06-01

    Although the development of the 2009 SpA classification criteria by Assessment of SpondyloArthritis international Society (ASAS) represents an important step towards a better definition of the early disease stage particularly in axial spondyloarthritis (axSpA), the specificity of the criteria has been criticized these days. As the commonest zoonotic infection worldwide, human brucellosis can mimic a large number of diseases, including SpA. This study was performed to determine the frequency of rheumatologic manifestations in patients with brucellosis and the chance of misdiagnosing them as having axSpA in central China. The results showed that clinical manifestations of axSpA could be observed in brucellosis. Over half of patients had back pain, and one fifth of the patients with back pain were less than 45 years old at onset and had the symptom for more than 3 months. Two young males were falsely classified as suffering from axSpA according to the ASAS criteria, and one with MRI proved sacroiliitis was once given Etanercept for treatment. Therefore, differential diagnosis including human brucellosis should always be kept in mind when applying the ASAS criteria, even in traditionally non-endemic areas.

  17. Case report: human papilloma virus type 120-related papillomatosis mimicking laryngeal carcinoma.

    Science.gov (United States)

    Belvisi, Valeria; Martellucci, Salvatore; Garbuglia, Anna Rosa; Del Borgo, Cosmo; Martellucci, Stanislao; Baiocchini, Andrea; Manicone, Anna Maria; Bagni, Oreste; Mastroianni, Claudio Maria; Gallo, Andrea

    2017-10-01

    The relationship between human papilloma virus (HPV) and upper respiratory tract pathology was better understood in recent years and represents now an issue of particular interest in carcinogenesis and in immunocompromised host. We describe a case in which a rare genotype HPV-related papillomatosis mimics laryngeal carcinoma in an immunocompromised host. A 54-year-old woman with a history of HIV-HCV coinfection and anal and laryngeal cancer successfully treated some years before was hospitalized for severe dyspnea, cough and dysphagia. Fiberoptic endoscopic evaluation raised the suspicion of tumor relapse showing the presence of a large glottic-supraglottic ulcerated mass. Several laryngeal biopsies demonstrated koilocytosis and p16 expression, according to a possible HPV infection, and focal figures of mild dysplasia of epithelium. 18 F-FDG PET/CT did not show high glycolytic activity at laryngeal level. An invasive upper respiratory tract papillomatosis in an immunocompromised host was suspected because of the patient's clinical improvement after antiretroviral therapy. Pharyngeal swab and oral rinse harboured the same HPV120 genotype sequence, a betapapillomavirus of recent description and not yet related to any similar clinical presentations.

  18. Novel experimental Pseudomonas aeruginosa lung infection model mimicking long-term host-pathogen interactions in cystic fibrosis

    DEFF Research Database (Denmark)

    Moser, Claus; van Gennip, Maria; Bjarnsholt, Thomas

    2009-01-01

    Moser C, van Gennip M, Bjarnsholt T, Jensen PO, Lee B, Hougen HP, Calum H, Ciofu O, Givskov M, Molin S, Hoiby N. Novel experimental Pseudomonas aeruginosa lung infection model mimicking long-term host-pathogen interactions in cystic fibrosis. APMIS 2009; 117: 95-107. The dominant cause of premature...... death in patients suffering from cystic fibrosis (CF) is chronic lung infection with Pseudomonas aeruginosa. The chronic lung infection often lasts for decades with just one clone. However, as a result of inflammation, antibiotic treatment and different niches in the lungs, the clone undergoes...... and 2003) of the chronic lung infection of one CF patient using the seaweed alginate embedment model. The results showed that the non-mucoid clones reduced their virulence over time, resulting in faster clearing of the bacteria from the lungs, improved pathology and reduced pulmonary production...

  19. A pacemaker powered by an implantable biofuel cell operating under conditions mimicking the human blood circulatory system--battery not included.

    Science.gov (United States)

    Southcott, Mark; MacVittie, Kevin; Halámek, Jan; Halámková, Lenka; Jemison, William D; Lobel, Robert; Katz, Evgeny

    2013-05-07

    Biocatalytic electrodes made of buckypaper were modified with PQQ-dependent glucose dehydrogenase on the anode and with laccase on the cathode and were assembled in a flow biofuel cell filled with serum solution mimicking the human blood circulatory system. The biofuel cell generated an open circuitry voltage, Voc, of ca. 470 mV and a short circuitry current, Isc, of ca. 5 mA (a current density of 0.83 mA cm(-2)). The power generated by the implantable biofuel cell was used to activate a pacemaker connected to the cell via a charge pump and a DC-DC converter interface circuit to adjust the voltage produced by the biofuel cell to the value required by the pacemaker. The voltage-current dependencies were analyzed for the biofuel cell connected to an Ohmic load and to the electronic loads composed of the interface circuit, or the power converter, and the pacemaker to study their operation. The correct pacemaker operation was confirmed using a medical device - an implantable loop recorder. Sustainable operation of the pacemaker was achieved with the system closely mimicking human physiological conditions using a single biofuel cell. This first demonstration of the pacemaker activated by the physiologically produced electrical energy shows promise for future electronic implantable medical devices powered by electricity harvested from the human body.

  20. Sensory nerve degeneration in a mouse model mimicking early manifestations of familial amyloid polyneuropathy due to transthyretin Ala97Ser.

    Science.gov (United States)

    Kan, H-W; Chiang, H; Lin, W-M; Yu, I-S; Lin, S-W; Hsieh, S-T

    2018-02-08

    Sensory nerve degeneration and consequent abnormal sensations are the earliest and most prevalent manifestations of familial amyloid polyneuropathy (FAP) due to amyloidogenic transthyretin (TTR). FAP is a relentlessly progressive degenerative disease of the peripheral nervous system. However, there is a lack of mouse models to replicate the early neuropathic manifestations of FAP. We established human TTR knock-in mice by replacing one allele of the mouse Ttr locus with human wild-type TTR (hTTR wt ) or human TTR with the A97S mutation (hTTR A97S ). Given the late onset of neuropathic manifestations in A97S-FAP, we investigated nerve pathology, physiology, and behavioural tests in these mice at two age points: the adult group (8 - 56 weeks) and the ageing group (> 104 weeks). In the adult group, nerve profiles, neurophysiology and behaviour were similar between hTTR wt and hTTR A97S mice. By contrast, ageing hTTR A97S mice showed small fibre neuropathy with decreased intraepidermal nerve fibre density and behavioural signs of mechanical allodynia. Furthermore, significant reductions in sural nerve myelinated nerve fibre density and sensory nerve action potential amplitudes in these mice indicated degeneration of large sensory fibres. The unaffected motor nerve physiology replicated the early symptoms of FAP patients, that is, sensory nerves were more vulnerable to mutant TTR than motor nerves. These results demonstrate that the hTTR A97S mouse model develops sensory nerve pathology and corresponding physiology mimicking A97S-FAP and provides a platform to develop new therapies for the early stage of A97S-FAP. © 2018 British Neuropathological Society.

  1. Validation of a sensitive DNA walking strategy to characterise unauthorised GMOs using model food matrices mimicking common rice products.

    Science.gov (United States)

    Fraiture, Marie-Alice; Herman, Philippe; Taverniers, Isabel; De Loose, Marc; Van Nieuwerburgh, Filip; Deforce, Dieter; Roosens, Nancy H

    2015-04-15

    To identify unauthorised GMOs in food and feed matrices, an integrated approach has recently been developed targeting pCAMBIA family vectors, highly present in transgenic plants. Their presence is first assessed by qPCR screening and is subsequently confirmed by characterising the transgene flanking regions, using DNA walking. Here, the DNA walking performance has been thoroughly tested for the first time, regarding the targeted DNA quality and quantity. Several assays, on model food matrices mimicking common rice products, have allowed to determine the limit of detection as well as the potential effects of food mixture and processing. This detection system allows the identification of transgenic insertions as low as 10 HGEs and was not affected by the presence of untargeted DNA. Moreover, despite the clear impact of food processing on DNA quality, this method was able to cope with degraded DNA. Given its specificity, sensitivity, reliability, applicability and practicability, the proposed approach is a key detection tool, easily implementable in enforcement laboratories. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Novel mouse model of chronic Pseudomonas aeruginosa lung infection mimicking cystic fibrosis

    DEFF Research Database (Denmark)

    Hoffmann, Nadine; Rasmussen, Thomas Bovbjerg; Jensen, Peter Østrup

    2005-01-01

    (NH57388C) from the mucoid isolate (NH57388A) and a nonmucoid isolate (NH57388B) deficient in AHL were almost cleared from the lungs of the mice. This model, in which P. aeruginosa is protected against the defense system of the lung by alginate, is similar to the clinical situation. Therefore...... pulmonary mouse model without artificial embedding. The model is based on a stable mucoid CF sputum isolate (NH57388A) with hyperproduction of alginate due to a deletion in mucA and functional N-acylhomoserine lactone (AHL)-based quorum-sensing systems. Chronic lung infection could be established in both CF...

  3. Measurement of guided mode wavenumbers in soft tissue–bone mimicking phantoms using ultrasonic axial transmission

    International Nuclear Information System (INIS)

    Chen Jiangang; Su Zhongqing; Cheng Li; Foiret, Josquin; Minonzio, Jean-Gabriel; Talmant, Maryline; Laugier, Pascal

    2012-01-01

    Human soft tissue is an important factor that influences the assessment of human long bones using quantitative ultrasound techniques. To investigate such influence, a series of soft tissue–bone phantoms (a bone-mimicking plate coated with a layer of water, glycerol or silicon rubber) were ultrasonically investigated using a probe with multi-emitter and multi-receiver arrays in an axial transmission configuration. A singular value decomposition signal processing technique was applied to extract the frequency-dependent wavenumbers of several guided modes. The results indicate that the presence of a soft tissue-mimicking layer introduces additional guided modes predicted by a fluid waveguide model. The modes propagating in the bone-mimicking plate covered by the soft-tissue phantom are only slightly modified compared to their counterparts in the free bone-mimicking plate, and they are still predicted by an elastic transverse isotropic two-dimensional waveguide. Altogether these observations suggest that the soft tissue–bone phantoms can be modeled as two independent waveguides. Even in the presence of the overlying soft tissue-mimicking layer, the modes propagating in the bone-mimicking plate can still be extracted and identified. These results suggest that our approach can be applied for the purpose of the characterization of the material and structural properties of cortical bone. (paper)

  4. Atmospheric modeling of Mars CH4 subsurface clathrates releases mimicking SAM and 2003 Earth-based detections

    Science.gov (United States)

    Pla-García, J.; Rafkin, S. C.

    2017-12-01

    The aim of this work is to establish the amount of mixing during all martian seasons to test whether CH4 releases inside or outside of Gale crater are consistent with MSL-SAM observations. Several modeling scenarios were configured, including instantaneous and steady releases, both inside and outside the crater. A simulation to mimic the 2003 Earth-based detections (Mumma et al. 2009 or M09) was also performed. In the instantaneous release inside Gale experiments, Ls270 was shown to be the faster mixing season when air within and outside the crater was well mixed: all tracer mass inside the crater is diluted after just 8 hours. The mixing of near surface crater air with the external environment in the rest of the year is potentially rapid but slower than Ls270.In the instantaneous release outside Gale (NW) experiment, in just 12 hours the CH4 that makes it to the MSL landing location is diluted by six orders of magnitude. The timescale of mixing in MRAMS experiments is on the order of 1 sol regardless of season. The duration of the CH4 peak observed by SAM is 100 sols. Therefore there is a steady release inside the crater, or there is a very large magnitude steady release outside the crater. In the steady release Gale experiments, CH4 flux rate from ground is 1.8 kg m-2 s-1 (derived from Gloesener et al. 2017 clathrates fluxes) and it is not predictive. In these experiments, 200 times lower CH4 values detected by SAM are modeled around MSL location. There are CH4 concentration variations of orders of magnitude depending on the hour, so timing of SAM measurements is important. With a larger (but further away) outside crater release area compared to inside, similar CH4 values around MSL are modeled, so distance to source is important. In the steady experiments mimicking M09 detection release area, only 12 times lower CH4 values detected by SAM are modeled around MSL. The highest value in the M09 modeled scenario (0.6 ppbv) is reached in Ls270. This value is the

  5. A new model mimicking persistent HBV e antigen-negative infection using covalently closed circular DNA in immunocompetent mice.

    Directory of Open Access Journals (Sweden)

    Lei Wang

    Full Text Available Despite the availability of an effective vaccine, hepatitis B virus (HBV infection remains a major health problem. HBV e antigen (HBeAg-negative strains have become prevalent. Previously, no animal model mimicked the clinical course of HBeAg-negative HBV infection. To establish an HBeAg-negative HBV infection model, the 3.2-kb full-length genome of HBeAg-negative HBV was cloned from a clinical sample and then circularized to form covalently closed circular (cccDNA. The resulting cccDNA was introduced into the liver of C57BL/6J mice through hydrodynamic injection. Persistence of the HBeAg-negative infection was monitored at predetermined time points using HBV-specific markers including HBV surface antigen (HBsAg, HBeAg, and HBV core antigen (HBcAg as well as DNA copies. Throughout the study, pAAV-HBV1.2 was used as a control. In mice injected with HBeAg-negative cccDNA, the HBV infection rate was 100% at the initial stage. HBsAg levels increased up to 1 week, at which point levels peaked and dropped quickly thereafter. In 60% of injected mice, HBsAg and HBcAg persisted for more than 10 weeks. High numbers of HBV DNA copies were detected in the serum and liver. Moreover, cccDNA persisted in the liver tissue of HBeAg-negative mice. In contrast to the pAAV-HBV 1.2 injected mice, no HBeAg was found in mice injected with HBeAg-negative HBV throughout the study period. These results demonstrate the first successful establishment of a model of HBeAg-negative HBV-persistent infection in immunocompetent mice. Compared to pAAV-HBV1.2-injected mice, the infection persistence and levels of serum virological and biochemical markers were approximately equal in the model mice. This model will be useful for mechanistic studies on HBeAg-negative HBV infection and will facilitate the evaluation of new antiviral drugs.

  6. Effect of liver histopathology on islet cell engraftment in the model mimicking autologous islet cell transplantation.

    Science.gov (United States)

    Desai, Chirag S; Khan, Khalid M; Ma, Xiaobo; Li, Henghong; Wang, Juan; Fan, Lijuan; Chen, Guoling; Smith, Jill P; Cui, Wanxing

    2017-11-02

    The inflammatory milieu in the liver as determined by histopathology is different in individual patients undergoing autologous islet cell transplantation. We hypothesized that inflammation related to fatty-liver adversely impacts islet survival. To test this hypothesis, we used a mouse model of fatty-liver to determine the outcome of syngeneic islet transplantation after chemical pancreatectomy. Mice (C57BL/6) were fed a high-fat-diet from 6 weeks of age until attaining a weight of ≥28 grams (6-8 weeks) to produce a fatty liver (histologically > 30% fat);steatosis was confirmed with lipidomic profile of liver tissue. Islets were infused via the intra-portal route in fatty-liver and control mice after streptozotocin induction of diabetes. Outcomes were assessed by the rate of euglycemia, liver histopathology, evaluation of liver inflammation by measuring tissue cytokines IL-1β and TNF-α by RT-PCR and CD31 expression by immunohistochemistry. The difference in the euglycemic fraction between the normal liver group (90%, 9/10) and the fatty-liver group (37.5%, 3/8) was statistically significant at the 18 th day post- transplant and was maintained to the end of the study (day 28) (p = 0.019, X 2 = 5.51). Levels of TNF-α and IL-1β were elevated in fatty-liver mice (p = 0.042, p = 0.037). Compared to controls cytokine levels were elevated after islet cell transplantation and in transplanted fatty-liver mice as compared to either fatty- or islet transplant group alone (p = NS). A difference in the histochemical pattern of CD31 could not be determined. Fatty-liver creates an inflammatory state which adversely affects the outcome of autologous islet cell transplantation.

  7. Reprodaetion of an animal model of multiple intestinal injuries mimicking "lethal triad" caused by severe penetrating abdominal trauma

    Directory of Open Access Journals (Sweden)

    Peng-fei WANG

    2011-03-01

    Full Text Available Objective To reproduce an animal model of multi-intestinal injuries with "lethal triad" characterized by low body temperature,acidosis and coagulopathy.Methods Six female domestic outbred pigs were anesthetized,and the carotid artery and jugular vein were cannulated for monitoring the blood pressure and heart rate and for infusion of fluid.The animals were shot with a gun to create a severe penetrating abdominal trauma.Immediately after the shooting,50% of total blood volume(35ml/kg hemorrhage was drawn from the carotid artery in 20min.After a 40min shock period,4h of pre-hospital phase was mimicked by normal saline(NS resuscitation to maintain systolic blood pressure(SBP > 80mmHg or mean arterial pressure(MAP > 60mmHg.When SBP > 80mmHg or MAP > 60mmHg,no fluid infusion or additional bleeding was given.Hemodynamic parameters were recorded,and pathology of myocardium,lung,small intestine and liver was observed.Results There were multiple intestinal perforations(8-10 site injuries/pig leading to intra-abdominal contamination,mesenteric injury(1-2 site injuries/pig resulted in partial intestinal ischemia and intra-abdominal hemorrhage,and no large colon and mesenteric vascular injury.One pig died before the completion of the model establishment(at the end of pre-hospital resuscitation.The typical symptoms of trauma-induced hemorrhagic shock were observed in survival animals.Low temperature(33.3±0.5℃,acidosis(pH=7.242±0.064,and coagulopathy(protrombin time and activated partial thromboplasting time prolonged were observed after pre-hospital resuscitation.Pathology showed that myocardium,lung,small intestine and liver were severely injured.Conclusions A new model,simulating three stages of "traumatic hemorrhagic shock,pre-hospital recovery and hospital treatment" and inducing the "lethal triad" accompanied with abdominal pollution,has been successfully established.This model has good stability and high reproducibility.The survival animals can be

  8. Design and Investigation of PolyFermS In Vitro Continuous Fermentation Models Inoculated with Immobilized Fecal Microbiota Mimicking the Elderly Colon.

    Science.gov (United States)

    Fehlbaum, Sophie; Chassard, Christophe; Haug, Martina C; Fourmestraux, Candice; Derrien, Muriel; Lacroix, Christophe

    2015-01-01

    In vitro gut modeling is a useful approach to investigate some factors and mechanisms of the gut microbiota independent of the effects of the host. This study tested the use of immobilized fecal microbiota to develop different designs of continuous colonic fermentation models mimicking elderly gut fermentation. Model 1 was a three-stage fermentation mimicking the proximal, transverse and distal colon. Models 2 and 3 were based on the new PolyFermS platform composed of an inoculum reactor seeded with immobilized fecal microbiota and used to continuously inoculate with the same microbiota different second-stage reactors mounted in parallel. The main gut bacterial groups, microbial diversity and metabolite production were monitored in effluents of all reactors using quantitative PCR, 16S rRNA gene 454-pyrosequencing, and HPLC, respectively. In all models, a diverse microbiota resembling the one tested in donor's fecal sample was established. Metabolic stability in inoculum reactors seeded with immobilized fecal microbiota was shown for operation times of up to 80 days. A high microbial and metabolic reproducibility was demonstrated for downstream control and experimental reactors of a PolyFermS model. The PolyFermS models tested here are particularly suited to investigate the effects of environmental factors, such as diet and drugs, in a controlled setting with the same microbiota source.

  9. Design and Investigation of PolyFermS In Vitro Continuous Fermentation Models Inoculated with Immobilized Fecal Microbiota Mimicking the Elderly Colon.

    Directory of Open Access Journals (Sweden)

    Sophie Fehlbaum

    Full Text Available In vitro gut modeling is a useful approach to investigate some factors and mechanisms of the gut microbiota independent of the effects of the host. This study tested the use of immobilized fecal microbiota to develop different designs of continuous colonic fermentation models mimicking elderly gut fermentation. Model 1 was a three-stage fermentation mimicking the proximal, transverse and distal colon. Models 2 and 3 were based on the new PolyFermS platform composed of an inoculum reactor seeded with immobilized fecal microbiota and used to continuously inoculate with the same microbiota different second-stage reactors mounted in parallel. The main gut bacterial groups, microbial diversity and metabolite production were monitored in effluents of all reactors using quantitative PCR, 16S rRNA gene 454-pyrosequencing, and HPLC, respectively. In all models, a diverse microbiota resembling the one tested in donor's fecal sample was established. Metabolic stability in inoculum reactors seeded with immobilized fecal microbiota was shown for operation times of up to 80 days. A high microbial and metabolic reproducibility was demonstrated for downstream control and experimental reactors of a PolyFermS model. The PolyFermS models tested here are particularly suited to investigate the effects of environmental factors, such as diet and drugs, in a controlled setting with the same microbiota source.

  10. Development of human skin equivalents mimicking skin aging : contrast between papillary and reticular fibroblasts as a lead

    NARCIS (Netherlands)

    Janson, D.

    2017-01-01

    This thesis describes the development of human skin equivalents that show characteristics of skin aging. The type of skin equivalent used was a fibroblast derived matrix equivalent, in which the dermal compartment is generated by fibroblasts and thus is fully of human origin. Two strategies are

  11. Models of human operators

    International Nuclear Information System (INIS)

    Knee, H.E.; Schryver, J.C.

    1991-01-01

    Models of human behavior and cognition (HB and C) are necessary for understanding the total response of complex systems. Many such models have come available over the past thirty years for various applications. Unfortunately, many potential model users remain skeptical about their practicality, acceptability, and usefulness. Such hesitancy stems in part to disbelief in the ability to model complex cognitive processes, and a belief that relevant human behavior can be adequately accounted for through the use of commonsense heuristics. This paper will highlight several models of HB and C and identify existing and potential applications in attempt to dispel such notions. (author)

  12. Conditional E2F1 activation in transgenic mice causes testicular atrophy and dysplasia mimicking human CIS

    DEFF Research Database (Denmark)

    Agger, Karl; Santoni-Rugiu, Eric; Holmberg, Christian

    2005-01-01

    E2F1 is a crucial downstream effector of the retinoblastoma protein (pRB) pathway. To address the consequences of short-term increase in E2F1 activity in adult tissues, we generated transgenic mice expressing the human E2F1 protein fused to the oestrogen receptor (ER) ligand-binding domain...

  13. Mimicking the tribo-mechanical performance of human skin: a scale dependent approach based on poly (vinyl alcohol) hydrogel

    NARCIS (Netherlands)

    Morales Hurtado, Marina

    2016-01-01

    The development of an appropriate substitute to simulate the frictional performance of human skin at different conditions is required for the design and optimization of products in contact with the skin. With this purpose, the composition, structure and mechanical properties of the skin need to be

  14. Digital Human Modeling

    Science.gov (United States)

    Dischinger, H. Charles, Jr.

    2017-01-01

    The development of models to represent human characteristics and behaviors in human factors is broad and general. The term "model" can refer to any metaphor to represent any aspect of the human; it is generally used in research to mean a mathematical tool for the simulation (often in software, which makes the simulation digital) of some aspect of human performance and for the prediction of future outcomes. This section is restricted to the application of human models in physical design, e.g., in human factors engineering. This design effort is typically human interface design, and the digital models used are anthropometric. That is, they are visual models that are the physical shape of humans and that have the capabilities and constraints of humans of a selected population. They are distinct from the avatars used in the entertainment industry (movies, video games, and the like) in precisely that regard: as models, they are created through the application of data on humans, and they are used to predict human response; body stresses workspaces. DHM enable iterative evaluation of a large number of concepts and support rapid analysis, as compared with use of physical mockups. They can be used to evaluate feasibility of escape of a suited astronaut from a damaged vehicle, before launch or after an abort (England, et al., 2012). Throughout most of human spaceflight, little attention has been paid to worksite design for ground workers. As a result of repeated damage to the Space Shuttle which adversely affected flight safety, DHM analyses of ground assembly and maintenance have been developed over the last five years for the design of new flight systems (Stambolian, 2012, Dischinger and Dunn Jackson, 2014). The intent of these analyses is to assure the design supports the work of the ground crew personnel and thereby protect the launch vehicle. They help the analyst address basic human factors engineering questions: can a worker reach the task site from the work platform

  15. The effect of sediment mimicking drill cuttings on deep water rhodoliths in a flow-through system: Experimental work and modeling

    International Nuclear Information System (INIS)

    Figueiredo, Marcia A.O.; Eide, Ingvar; Reynier, Marcia; Villas-Bôas, Alexandre B.; Tâmega, Frederico T.S.

    2015-01-01

    Highlights: • Collection of rhodoliths and calcareous algae from Campos Basin, Brazil. • Impact of sediment mimicking drill cuttings on photosynthetic efficiency. • Exposure–response for photosynthetic efficiency as function of sediment coverage. • Factorial design and multivariate regression used for a structured approach. - Abstract: The impact of sediment coverage on two rhodolith-forming calcareous algae species collected at 100 m water depth off the coast of Brazil was studied in an experimental flow-through system. Natural sediment mimicking drill cuttings with respect to size distribution was used. Sediment coverage and photosynthetic efficiency (maximum quantum yield of charge separation in photosystem II, ϕ PSIImax ) were measured as functions of light intensity, flow rate and added amount of sediment once a week for nine weeks. Statistical experimental design and multivariate data analysis provided statistically significant regression models which subsequently were used to establish exposure–response relationship for photosynthetic efficiency as function of sediment coverage. For example, at 70% sediment coverage the photosynthetic efficiency was reduced 50% after 1–2 weeks of exposure, most likely due to reduced gas exchange. The exposure–response relationship can be used to establish threshold levels and impact categories for environmental monitoring

  16. Skin absorption and human exposure estimation of three widely discussed UV filters in sunscreens--In vitro study mimicking real-life consumer habits.

    Science.gov (United States)

    Klimová, Z; Hojerová, J; Beránková, M

    2015-09-01

    Due to health concerns about safety, three UV-filters (Benzophenone-3, BP3, 10%; Ethylhexyl Methoxycinnamate, EHMC, 10%; Butyl Methoxydibenzoylmethane, BMDBM; 5%) were examined in vitro for absorption on full-thickness pig-ear skin, mimicking human in-use conditions. Kinetic profiles confirmed the rapid permeation of BP3; after the first hour of skin (frozen-stored) exposure to 2 mg/cm(2) (W/O sunscreen; recommended but unrealistic amount), about 0.5% of the applied dose passed into the receptor fluid. The absorption rate of filters was higher from W/O than from O/W emulsions. The fresh/frozen-stored skin permeability coefficient (0.83-0.54) for each UV filter was taken into account. Systemic Exposure Dosage of BP3, EHMC, BMDBM for humans as a consequence of (i) whole-body and (ii) face treatment with 0.5 mg/cm(2) of W/O sunscreen for 6-h skin exposure followed by washing and subsequent 18-h permeation (a realistic scenario) were estimated to be (i) 4744, 1032 and 1036 μg/kg-bw/day, and (ii) 153, 33 and 34 μg/kg-bw/day, respectively. From Margin of Safety for BP3, EHMC and BMDBM (i) 42, 485 and 192 as well as (ii) 1307; 15,151 and 5882, respectively, only the value of 42 (<100) for BP3 indicated a possible health risk. Escalation of a phobia towards all organic UV filters is undesirable. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. The application of silicon sol-gel technology to forensic blood substitute development: Mimicking aspects of whole human blood rheology.

    Science.gov (United States)

    Stotesbury, Theresa; Illes, Mike; Wilson, Paul; Vreugdenhil, Andrew J

    2017-01-01

    Solution-gelation chemistry has promising applications in forensic synthetic blood substitute development. This research offers a silicon-based sol-gel approach to creating stable materials that share similar rheological properties to that of whole human blood samples. Room temperature, high water content, silicon sol-gels were created using the organosilane precursors 3-glycidoxypropyltrimethoxysilane and tetraethylorthosilicate along with various concentrations of filler and pigment. Shear-thinning non-Newtonian properties were observed within most formulations of the presented materials. The effects of colloidal concentration, temperature, age and filler addition on the viscosity of the sol-gels were investigated. SEM-EDS analysis was used to identify the behavior of the fillers within the film and support their inclusion for basic bloodstain pattern simulation. A final proposed candidate sol-gel was assessed using a previously reported passive drip simulation test on a hard, dry surface and passed. This works represents encouraging development in providing safe material alternatives to using whole human blood for forensic training and research. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. Cerebral gumma mimicking a brain tumor in a human immunodeficiency virus-negative patient: A case report

    International Nuclear Information System (INIS)

    Baek, Hye Jin; Kim, Woo Jin

    2013-01-01

    Syphilis has a broad spectrum of clinical manifestations, and the cerebral gumma is a kind of neurosyphilis which is rare and can be cured by appropriate antibiotic treatments. However, in clinical practices, diagnosis of cerebral syphilitic gumma is often difficult because imaging and laboratory findings revealed elusive results. Herein, we present a rare case of neurosyphilis presenting as cerebral gumma confirmed by histopathological examination, and positive serologic and cerebrospinal fluid analyses. This case report suggests that cerebral gumma should be considered as possible diagnosis for human immunodeficiency virus-negative patients with space-occupying lesion of the brain. And this case also provides importance of clinical suspicions in diagnosing neurosyphilis because syphilis serology is not routinely tested on patients with neurologic symptoms.

  19. Cerebral gumma mimicking a brain tumor in a human immunodeficiency virus-negative patient: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Hye Jin; Kim, Woo Jin [Haeundae Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

    2013-09-15

    Syphilis has a broad spectrum of clinical manifestations, and the cerebral gumma is a kind of neurosyphilis which is rare and can be cured by appropriate antibiotic treatments. However, in clinical practices, diagnosis of cerebral syphilitic gumma is often difficult because imaging and laboratory findings revealed elusive results. Herein, we present a rare case of neurosyphilis presenting as cerebral gumma confirmed by histopathological examination, and positive serologic and cerebrospinal fluid analyses. This case report suggests that cerebral gumma should be considered as possible diagnosis for human immunodeficiency virus-negative patients with space-occupying lesion of the brain. And this case also provides importance of clinical suspicions in diagnosing neurosyphilis because syphilis serology is not routinely tested on patients with neurologic symptoms.

  20. Humanized mouse models: Application to human diseases.

    Science.gov (United States)

    Ito, Ryoji; Takahashi, Takeshi; Ito, Mamoru

    2018-05-01

    Humanized mice are superior to rodents for preclinical evaluation of the efficacy and safety of drug candidates using human cells or tissues. During the past decade, humanized mouse technology has been greatly advanced by the establishment of novel platforms of genetically modified immunodeficient mice. Several human diseases can be recapitulated using humanized mice due to the improved engraftment and differentiation capacity of human cells or tissues. In this review, we discuss current advanced humanized mouse models that recapitulate human diseases including cancer, allergy, and graft-versus-host disease. © 2017 Wiley Periodicals, Inc.

  1. p16 expression in follicular dendritic cell sarcoma: a potential mimicker of human papillomavirus-related oropharyngeal squamous cell carcinoma.

    Science.gov (United States)

    Zhang, Lingxin; Yang, Chen; Lewis, James S; El-Mofty, Samir K; Chernock, Rebecca D

    2017-08-01

    Follicular dendritic cell sarcoma is a rare mesenchymal neoplasm that most commonly occurs in cervical lymph nodes. It has histologic and clinical overlap with the much more common p16-positive human papillomavirus (HPV)-related squamous cell carcinoma of the oropharynx, which characteristically has nonkeratinizing morphology and often presents as an isolated neck mass. Not surprisingly, follicular dendritic cell sarcomas are commonly misdiagnosed as squamous cell carcinoma. Immunohistochemistry is helpful in separating the 2 entities. Follicular dendritic cell sarcoma expresses dendritic markers such as CD21 and CD23 and is almost always cytokeratin negative. However, in many cases of HPV-related oropharyngeal carcinoma, only p16 immunohistochemistry as a prognostic and surrogate marker for HPV is performed. p16 expression in follicular dendritic cell sarcoma has not been characterized. Here, we investigate the expression of p16 in follicular dendritic cell sarcoma and correlate it with retinoblastoma protein expression. A pilot study of dendritic marker expression in HPV-related oropharyngeal squamous cell carcinoma was also performed. We found that 4 of 8 sarcomas expressed p16 with strong and diffuse staining in 2 cases. In 2 of the 4 cases, p16 expression corresponded to loss of retinoblastoma protein expression. Dendritic marker expression (CD21 and CD23) was not found in HPV-related oropharyngeal squamous cell carcinomas. As such, positive p16 immunohistochemistry cannot be used as supportive evidence for the diagnosis of squamous cell carcinoma as strong and diffuse p16 expression may also occur in follicular dendritic cell sarcoma. Cytokeratins and dendritic markers are critical in separating the two tumor types. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Methyl-orvinol-Dual activity opioid receptor ligand inhibits gastrointestinal transit and alleviates abdominal pain in the mouse models mimicking diarrhea-predominant irritable bowel syndrome.

    Science.gov (United States)

    Zielińska, Marta; Jarmuż, Agata; Wasilewski, Andrzej; Cami-Kobeci, Gerta; Husbands, Stephen; Fichna, Jakub

    2017-04-01

    Diarrhea-predominant irritable bowel syndrome (IBS-D) is a functional disorder of the gastrointestinal (GI) tract. The major IBS-D symptoms include diarrhea, abdominal pain and discomfort. High density of opioid receptors (ORs) in the GI tract and their participation in the maintenance of GI homeostasis make ORs ligands an attractive option for developing new anti-IBS-D treatments. The aim of this study was to characterize the effect of methyl-orvinol on the GI motility and secretion and in mouse models mimicking symptoms of IBS-D. In vitro, the effects of methyl-orvinol on electrical field stimulated smooth muscle contractility and epithelial ion transport were characterized in the mouse colon. In vivo, the following tests were used to determine methyl-orvinol effect on mouse GI motility: colonic bead expulsion, whole GI transit and fecal pellet output. An antinociceptive action of methyl-orvinol was assessed in the mouse model of visceral pain induced by mustard oil. Methyl-orvinol (10 -10 to 10 -6 M) inhibited colonic smooth muscle contractions in a concentration-dependent manner. This effect was reversed by naloxone (non-selective opioid antagonist) and β-funaltrexamine (selective MOP antagonist). Experiments with a selective KOP receptor agonist, U50488 revealed that methyl-orvinol is a KOP receptor antagonist in the GI tract. Methyl-orvinol enhanced epithelial ion transport. In vivo, methyl-orvinol inhibited colonic bead expulsion and prolonged GI transit. Methyl-orvinol improved hypermotility and reduced abdominal pain in the mouse models mimicking IBS-D symptoms. Methyl-orvinol could become a promising drug candidate in chronic therapy of functional GI diseases such as IBS-D. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  3. Longitudinal analysis of osteogenic and angiogenic signaling factors in healing models mimicking atrophic and hypertrophic non-unions in rats.

    Directory of Open Access Journals (Sweden)

    Susann Minkwitz

    Full Text Available Impaired bone healing can have devastating consequences for the patient. Clinically relevant animal models are necessary to understand the pathology of impaired bone healing. In this study, two impaired healing models, a hypertrophic and an atrophic non-union, were compared to physiological bone healing in rats. The aim was to provide detailed information about differences in gene expression, vascularization and histology during the healing process. The change from a closed fracture (healing control group to an open osteotomy (hypertrophy group led to prolonged healing with reduced mineralized bridging after 42 days. RT-PCR data revealed higher gene expression of most tested osteogenic and angiogenic factors in the hypertrophy group at day 14. After 42 days a significant reduction of gene expression was seen for Bmp4 and Bambi in this group. The inhibition of angiogenesis by Fumagillin (atrophy group decreased the formation of new blood vessels and led to a non-healing situation with diminished chondrogenesis. RT-PCR results showed an attempt towards overcoming the early perturbance by significant up regulation of the angiogenic regulators Vegfa, Angiopoietin 2 and Fgf1 at day 7 and a further continuous increase of Fgf1, -2 and Angiopoietin 2 over time. However µCT angiograms showed incomplete recovery after 42 days. Furthermore, lower expression values were detected for the Bmps at day 14 and 21. The Bmp antagonists Dan and Twsg1 tended to be higher expressed in the atrophy group at day 42. In conclusion, the investigated animal models are suitable models to mimic human fracture healing complications and can be used for longitudinal studies. Analyzing osteogenic and angiogenic signaling patterns, clear changes in expression were identified between these three healing models, revealing the importance of a coordinated interplay of different factors to allow successful bone healing.

  4. Human modeling in nuclear engineering

    International Nuclear Information System (INIS)

    Yoshikawa, Hidekazu; Furuta, Kazuo.

    1994-01-01

    Review on progress of research and development on human modeling methods is made from the viewpoint of its importance on total man-machine system reliability surrounding nuclear power plant operation. Basic notions on three different approaches of human modeling (behavioristics, cognitives and sociologistics) are firstly introduced, followed by the explanation of fundamental scheme to understand human cognitives at man-machine interface and the mechanisms of human error and its classification. Then, general methodologies on human cognitive model by AI are explained with the brief summary of various R and D activities now prevailing in the human modeling communities around the world. A new method of dealing with group human reliability is also introduced which is based on sociologistic mathematical model. Lastly, problems on human model validation are discussed, followed by the introduction of new experimental method to estimate human cognitive state by psycho-physiological measurement, which is a new methodology plausible for human model validation. (author)

  5. Novel orally available salvinorin A analog PR-38 inhibits gastrointestinal motility and reduces abdominal pain in mouse models mimicking irritable bowel syndrome.

    Science.gov (United States)

    Sałaga, M; Polepally, P R; Sobczak, M; Grzywacz, D; Kamysz, W; Sibaev, A; Storr, M; Do Rego, J C; Zjawiony, J K; Fichna, J

    2014-07-01

    The opioid and cannabinoid systems play a crucial role in multiple physiological processes in the central nervous system and in the periphery. Selective opioid as well as cannabinoid (CB) receptor agonists exert a potent inhibitory action on gastrointestinal (GI) motility and pain. In this study, we examined (in vitro and in vivo) whether PR-38 (2-O-cinnamoylsalvinorin B), a novel analog of salvinorin A, can interact with both systems and demonstrate therapeutic effects. We used mouse models of hypermotility, diarrhea, and abdominal pain. We also assessed the influence of PR-38 on the central nervous system by measurement of motoric parameters and exploratory behaviors in mice. Subsequently, we investigated the pharmacokinetics of PR-38 in mouse blood samples after intraperitoneal and oral administration. PR-38 significantly inhibited mouse colonic motility in vitro and in vivo. Administration of PR-38 significantly prolonged the whole GI transit time, and this effect was mediated by µ- and κ-opioid receptors and the CB1 receptor. PR-38 reversed hypermotility and reduced pain in mouse models mimicking functional GI disorders. These data expand our understanding of the interactions between opioid and cannabinoid systems and their functions in the GI tract. We also provide a novel framework for the development of future potential treatments of functional GI disorders. Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.

  6. Modeling Human Leukemia Immunotherapy in Humanized Mice

    Directory of Open Access Journals (Sweden)

    Jinxing Xia

    2016-08-01

    Full Text Available The currently available human tumor xenograft models permit modeling of human cancers in vivo, but in immunocompromised hosts. Here we report a humanized mouse (hu-mouse model made by transplantation of human fetal thymic tissue plus hematopoietic stem cells transduced with a leukemia-associated fusion gene MLL-AF9. In addition to normal human lymphohematopoietic reconstitution as seen in non-leukemic hu-mice, these hu-mice showed spontaneous development of B-cell acute lymphoblastic leukemia (B-ALL, which was transplantable to secondary recipients with an autologous human immune system. Using this model, we show that lymphopenia markedly improves the antitumor efficacy of recipient leukocyte infusion (RLI, a GVHD-free immunotherapy that induces antitumor responses in association with rejection of donor chimerism in mixed allogeneic chimeras. Our data demonstrate the potential of this leukemic hu-mouse model in modeling leukemia immunotherapy, and suggest that RLI may offer a safe treatment option for leukemia patients with severe lymphopenia.

  7. Confronting dark energy models mimicking ΛCDM epoch with observational constraints: Future cosmological perturbations decay or future Rip?

    International Nuclear Information System (INIS)

    Astashenok, Artyom V.; Odintsov, Sergei D.

    2013-01-01

    We confront dark energy models which are currently similar to ΛCDM theory with observational data which include the SNe data, matter density perturbations and baryon acoustic oscillations data. DE cosmology under consideration may evolve to Big Rip, type II or type III future singularity, or to Little Rip or Pseudo-Rip universe. It is shown that matter perturbations data define more precisely the possible deviation from ΛCDM model than consideration of SNe data only. The combined data analysis proves that DE models under consideration are as consistent as ΛCDM model. We demonstrate that growth of matter density perturbations may occur at sufficiently small background density but still before the possible disintegration of bound objects (like clusters of galaxies, galaxies, etc.) in Big Rip, type III singularity, Little Rip or Pseudo-Rip universe. This new effect may bring the future universe to chaotic state well before disintegration or Rip.

  8. Characterisation of enterocolitis in the piroxicam-accelerated interleukin-10 knock out mouse--a model mimicking inflammatory bowel disease.

    Science.gov (United States)

    Holgersen, Kristine; Kvist, Peter Helding; Markholst, Helle; Hansen, Axel Kornerup; Holm, Thomas Lindebo

    2014-02-01

    In inflammatory bowel disease a defective mucosal barrier, a dysregulated immune response and an excessive reactivity against the gut microbiota are assumed to cause a breakdown of the intestinal homeostasis and lead to chronic inflammation. Piroxicam treatment is a method for induction of colitis in IL-10 k.o. mice, which integrates a dysfunction of both the intestinal barrier and the immune system. However, the translational value of this model has not been thoroughly clarified. To characterise the piroxicam-accelerated colitis (PAC) IL-10 k.o. model with respect to clinical features, pathogenic mechanisms and its ability to respond to existing therapies. The PAC IL-10k.o. model was established on a C57BL/6J background and the clinical manifestations, immunological mechanisms and efficacy of ampicillin and anti-IL-12/23p40 treatment were assessed. The PAC IL-10 k.o. mice developed weight loss and diarrhoea, and colonoscopy revealed a thickened granulomatous mucosa. Histological evaluation of ileum and colon showed Crohn's disease-like changes with pronounced hyperplasia and focal transmural inflammation. Ileitis was also observed in piroxicam treated wild type mice. The total number of neutrophils, monocytes and natural killer cells was elevated in the blood compared to IL-10 k.o. and wild type mice, indicating a role of the innate immune system in the pathogenesis. These findings were supported by analyses of the intestinal cytokine profile. Ampicillin and anti-IL-12/23p40 treatment significantly suppressed disease in the model. The PAC IL-10 k.o. model resembles several features of Crohn's disease and could be a useful in vivo model in preclinical research. © 2013 Elsevier B.V. All rights reserved.

  9. Mimicking emotions: how 3-12-month-old infants use the facial expressions and eyes of a model.

    Science.gov (United States)

    Soussignan, Robert; Dollion, Nicolas; Schaal, Benoist; Durand, Karine; Reissland, Nadja; Baudouin, Jean-Yves

    2018-06-01

    While there is an extensive literature on the tendency to mimic emotional expressions in adults, it is unclear how this skill emerges and develops over time. Specifically, it is unclear whether infants mimic discrete emotion-related facial actions, whether their facial displays are moderated by contextual cues and whether infants' emotional mimicry is constrained by developmental changes in the ability to discriminate emotions. We therefore investigate these questions using Baby-FACS to code infants' facial displays and eye-movement tracking to examine infants' looking times at facial expressions. Three-, 7-, and 12-month-old participants were exposed to dynamic facial expressions (joy, anger, fear, disgust, sadness) of a virtual model which either looked at the infant or had an averted gaze. Infants did not match emotion-specific facial actions shown by the model, but they produced valence-congruent facial responses to the distinct expressions. Furthermore, only the 7- and 12-month-olds displayed negative responses to the model's negative expressions and they looked more at areas of the face recruiting facial actions involved in specific expressions. Our results suggest that valence-congruent expressions emerge in infancy during a period where the decoding of facial expressions becomes increasingly sensitive to the social signal value of emotions.

  10. Modeling human color categorization

    NARCIS (Netherlands)

    van den Broek, Egon; Schouten, Th.E.; Kisters, P.M.F.

    A unique color space segmentation method is introduced. It is founded on features of human cognition, where 11 color categories are used in processing color. In two experiments, human subjects were asked to categorize color stimuli into these 11 color categories, which resulted in markers for a

  11. Human migraine models

    DEFF Research Database (Denmark)

    Iversen, Helle Klingenberg

    2001-01-01

    , which is a human experience. A set-up for investigations of experimental headache and migraine in humans, has been evaluated and headache mechanisms explored by using nitroglycerin and other headache-inducing agents. Nitric oxide (NO) or other parts of the NO activated cascade seems to be responsible...

  12. Integrated Environmental Modelling: Human decisions, human challenges

    Science.gov (United States)

    Glynn, Pierre D.

    2015-01-01

    Integrated Environmental Modelling (IEM) is an invaluable tool for understanding the complex, dynamic ecosystems that house our natural resources and control our environments. Human behaviour affects the ways in which the science of IEM is assembled and used for meaningful societal applications. In particular, human biases and heuristics reflect adaptation and experiential learning to issues with frequent, sharply distinguished, feedbacks. Unfortunately, human behaviour is not adapted to the more diffusely experienced problems that IEM typically seeks to address. Twelve biases are identified that affect IEM (and science in general). These biases are supported by personal observations and by the findings of behavioural scientists. A process for critical analysis is proposed that addresses some human challenges of IEM and solicits explicit description of (1) represented processes and information, (2) unrepresented processes and information, and (3) accounting for, and cognizance of, potential human biases. Several other suggestions are also made that generally complement maintaining attitudes of watchful humility, open-mindedness, honesty and transparent accountability. These suggestions include (1) creating a new area of study in the behavioural biogeosciences, (2) using structured processes for engaging the modelling and stakeholder communities in IEM, and (3) using ‘red teams’ to increase resilience of IEM constructs and use.

  13. Towards an in vitro model mimicking the foreign body response: tailoring the surface properties of biomaterials to modulate extracellular matrix.

    Science.gov (United States)

    Damanik, Febriyani F R; Rothuizen, Tonia C; van Blitterswijk, Clemens; Rotmans, Joris I; Moroni, Lorenzo

    2014-09-19

    Despite various studies to minimize host reaction following a biomaterial implantation, an appealing strategy in regenerative medicine is to actively use such an immune response to trigger and control tissue regeneration. We have developed an in vitro model to modulate the host response by tuning biomaterials' surface properties through surface modifications techniques as a new strategy for tissue regeneration applications. Results showed tunable surface topography, roughness, wettability, and chemistry by varying treatment type and exposure, allowing for the first time to correlate the effect of these surface properties on cell attachment, morphology, strength and proliferation, as well as proinflammatory (IL-1β, IL-6) and antiinflammatory cytokines (TGF-β1, IL-10) secreted in medium, and protein expression of collagen and elastin. Surface microstructuring, derived from chloroform partial etching, increased surface roughness and oxygen content. This resulted in enhanced cell adhesion, strength and proliferation as well as a balance of soluble factors for optimum collagen and elastin synthesis for tissue regeneration. By linking surface parameters to cell activity, we could determine the fate of the regenerated tissue to create successful soft tissue-engineered replacement.

  14. Randomized clinical trial comparing manual suture and different models of mechanical suture in the mimicking of bariatric surgery in swine

    Directory of Open Access Journals (Sweden)

    Fernandes MA

    2014-02-01

    Full Text Available Marcos AP Fernandes,1 Bruno MT Pereira,2 Sandra M Guimarães,1 Aline Paganelli,3 Carlos Manoel CT Pereira,1 Claudio Sergio Batista4 1Institute of Obesity and Advanced Video Laparoscopic Surgery of Petropolis, Rio de Janeiro, Brazil; 2Division of Trauma, University of Campinas, São Paulo, Brazil; 3Laboratório de Patologia Micron Cell Diagnóstico, Rio de Janeiro, Brazil; 4Department of Gynecology and Obstetrics, Faculty of Medicine of Petropolis, Rio de Janeiro, Brazil Context and objective: Variations in the ability of surgeons served as motivation for the development of devices that, overcoming individual differences, allow the techniques to be properly performed, and of which the end result was the best possible. Every technique must be reproduced reliably by the majority of surgeons for their results to be adopted and recognized as effective. The aim of this study was to compare the results, from the point of view of anatomic pathology, of manual sutures versus mechanical sutures using different models of linear mechanical staplers, in the procedure of gastroenteroanastomosis and enteroanastomosis in swine. Methods: Thirty-six healthy, adult, male Sus scrofa domesticus pigs, weighing between 20.7 and 25.5 kg, were used. The swine were randomly divided into four groups of nine pigs, according to the type of suture employed: group A, manual suture with Polysorb® 3-0 wire; group B, 80-shear linear stapler (Covidien® Gia 8038-S; group C, 75-shear linear stapler (Ethicon® Tlc 75; and group D, 75-shear linear stapler (Resource® Yq 75-3. A temporal study was established on the seventh postoperative day for histopathological analysis, and the degree of inflammation, fibrosis, and newly formed vessels, as well as the presence or absence of granulation tissue, foreign body granuloma, and necrosis were all evaluated qualitatively and semiquantitatively. The results were analyzed statistically. Results: Observations during the histopathological

  15. Contemporary Animal Models For Human Gene Therapy Applications.

    Science.gov (United States)

    Gopinath, Chitra; Nathar, Trupti Job; Ghosh, Arkasubhra; Hickstein, Dennis Durand; Nelson, Everette Jacob Remington

    2015-01-01

    Over the past three decades, gene therapy has been making considerable progress as an alternative strategy in the treatment of many diseases. Since 2009, several studies have been reported in humans on the successful treatment of various diseases. Animal models mimicking human disease conditions are very essential at the preclinical stage before embarking on a clinical trial. In gene therapy, for instance, they are useful in the assessment of variables related to the use of viral vectors such as safety, efficacy, dosage and localization of transgene expression. However, choosing a suitable disease-specific model is of paramount importance for successful clinical translation. This review focuses on the animal models that are most commonly used in gene therapy studies, such as murine, canine, non-human primates, rabbits, porcine, and a more recently developed humanized mice. Though small and large animals both have their own pros and cons as disease-specific models, the choice is made largely based on the type and length of study performed. While small animals with a shorter life span could be well-suited for degenerative/aging studies, large animals with longer life span could suit longitudinal studies and also help with dosage adjustments to maximize therapeutic benefit. Recently, humanized mice or mouse-human chimaeras have gained interest in the study of human tissues or cells, thereby providing a more reliable understanding of therapeutic interventions. Thus, animal models are of great importance with regard to testing new vector technologies in vivo for assessing safety and efficacy prior to a gene therapy clinical trial.

  16. Non-human Primate Models for Brain Disorders - Towards Genetic Manipulations via Innovative Technology.

    Science.gov (United States)

    Qiu, Zilong; Li, Xiao

    2017-04-01

    Modeling brain disorders has always been one of the key tasks in neurobiological studies. A wide range of organisms including worms, fruit flies, zebrafish, and rodents have been used for modeling brain disorders. However, whether complicated neurological and psychiatric symptoms can be faithfully mimicked in animals is still debatable. In this review, we discuss key findings using non-human primates to address the neural mechanisms underlying stress and anxiety behaviors, as well as technical advances for establishing genetically-engineered non-human primate models of autism spectrum disorders and other disorders. Considering the close evolutionary connections and similarity of brain structures between non-human primates and humans, together with the rapid progress in genome-editing technology, non-human primates will be indispensable for pathophysiological studies and exploring potential therapeutic methods for treating brain disorders.

  17. Mimicking herpes simplex virus 1 and herpes simplex virus 2 mucosal behavior in a well-characterized human genital organ culture.

    Science.gov (United States)

    Steukers, Lennert; Weyers, Steven; Yang, Xiaoyun; Vandekerckhove, Annelies P; Glorieux, Sarah; Cornelissen, Maria; Van den Broeck, Wim; Temmerman, Marleen; Nauwynck, Hans J

    2014-07-15

    We developed and morphologically characterized a human genital mucosa explant model (endocervix and ectocervix/vagina) to mimic genital herpes infections caused by herpes simplex virus types 1 (HSV-1) and 2 (HSV-2). Subsequent analysis of HSV entry receptor expression throughout the menstrual cycle in genital tissues was performed, and the evolution of HSV-1/-2 mucosal spread over time was assessed. Nectin-1 and -2 were expressed in all tissues during the entire menstrual cycle. Herpesvirus entry mediator expression was limited mainly to some connective tissue cells. Both HSV-1 and HSV-2 exhibited a plaque-wise mucosal spread across the basement membrane and induced prominent epithelial syncytia. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  18. Human mobility: Models and applications

    Science.gov (United States)

    Barbosa, Hugo; Barthelemy, Marc; Ghoshal, Gourab; James, Charlotte R.; Lenormand, Maxime; Louail, Thomas; Menezes, Ronaldo; Ramasco, José J.; Simini, Filippo; Tomasini, Marcello

    2018-03-01

    Recent years have witnessed an explosion of extensive geolocated datasets related to human movement, enabling scientists to quantitatively study individual and collective mobility patterns, and to generate models that can capture and reproduce the spatiotemporal structures and regularities in human trajectories. The study of human mobility is especially important for applications such as estimating migratory flows, traffic forecasting, urban planning, and epidemic modeling. In this survey, we review the approaches developed to reproduce various mobility patterns, with the main focus on recent developments. This review can be used both as an introduction to the fundamental modeling principles of human mobility, and as a collection of technical methods applicable to specific mobility-related problems. The review organizes the subject by differentiating between individual and population mobility and also between short-range and long-range mobility. Throughout the text the description of the theory is intertwined with real-world applications.

  19. A natural human hand model

    NARCIS (Netherlands)

    Van Nierop, O.A.; Van der Helm, A.; Overbeeke, K.J.; Djajadiningrat, T.J.P.

    2007-01-01

    We present a skeletal linked model of the human hand that has natural motion. We show how this can be achieved by introducing a new biology-based joint axis that simulates natural joint motion and a set of constraints that reduce an estimated 150 possible motions to twelve. The model is based on

  20. A Comparative Analysis of Ability of Mimicking Portfolios in Representing the Background Factors

    OpenAIRE

    Asgharian, Hossein

    2004-01-01

    Our aim is to give a comparative analysis of ability of different factor mimicking portfolios in representing the background factors. Our analysis contains a cross-sectional regression approach, a time-series regression approach and a portfolio approach for constructing factor mimicking portfolios. The focus of the analysis is the power of mimicking portfolios in the asset pricing models. We conclude that the time series regression approach, with the book-to-market sorted portfolios as the ba...

  1. Dialectical Model of Human Nature

    OpenAIRE

    Cachat, Jonathan

    2013-01-01

    The DMoHN is a graphical representation of my current understanding and conceptualization of human nature, in addition to embodying the guiding ethos of social neuroscience. The dialectic is a logic, or way of thinking that joins opposite elements together in a uniting fashion to create emergent attributes not present in the elements alone. The dialectical structure of this model explicitly links Culture and Biology within the human brain in order to convey the symbiotic and dynamic interacti...

  2. Brucellar spondylodiscitis mimicking tuberculosis

    Directory of Open Access Journals (Sweden)

    Eshani Dewan

    2015-01-01

    Full Text Available Brucellosis is primarily a disease of domestic and wild animals that can be transmitted to humans (zoonosis. Infection with Brucella spp. continues to pose human health risk globally. Brucellosis in endemic and nonendemic regions remains a diagnostic puzzle due to misleading nonspecific manifestations and increasing unusual presentations. It may affect any organ of the body with clinical manifestations that include fever, joint pains, loss of weight, sweating, cough, sciatica, splenic enlargement, liver enlargement, orchitis, etc. Fewer than 10% of human cases of brucellosis may be clinically recognized and treated or reported. Routine serological surveillance is not practiced even in Brucella endemic countries. Whereas, this should be a part of laboratory testing coupled with a high index of clinical suspicion to improve the level of case detection. Rapid and reliable, sensitive and specific, easy to perform and semi-automated detection systems for Brucella spp. are urgently needed to allow early diagnosis and adequate antibiotic therapy in time to decrease morbidity and mortality.

  3. Sparganosis of the Breast that Mimicked Metastasis: A Case Report

    International Nuclear Information System (INIS)

    Kim, Jae Woon; Hwang, Mi Soo

    2011-01-01

    Sparganosis of the breast is a rare parasitic infection of humans. If the breast is involved, then this condition presents as soft tissue masses that mimic breast cancer. We report here on the radiologic feature of sparganosis in a patient with gastric cancer and this mimicked metastasis. We also briefly review the relevant literature

  4. Human Modeling for Ground Processing Human Factors Engineering Analysis

    Science.gov (United States)

    Stambolian, Damon B.; Lawrence, Brad A.; Stelges, Katrine S.; Steady, Marie-Jeanne O.; Ridgwell, Lora C.; Mills, Robert E.; Henderson, Gena; Tran, Donald; Barth, Tim

    2011-01-01

    There have been many advancements and accomplishments over the last few years using human modeling for human factors engineering analysis for design of spacecraft. The key methods used for this are motion capture and computer generated human models. The focus of this paper is to explain the human modeling currently used at Kennedy Space Center (KSC), and to explain the future plans for human modeling for future spacecraft designs

  5. Experimental investigation and theoretical modelling of the nonlinear acoustical behaviour of a liver tissue and comparison with a tissue mimicking hydrogel.

    Science.gov (United States)

    Casciaro, Sergio; Demitri, Christian; Conversano, Francesco; Casciaro, Ernesto; Distante, Alessandro

    2008-02-01

    Native harmonics generated by nonlinear distortion of ultrasound during propagation in a medium may cause misinterpretations in spectral analysis when studying contrast agents. The aim of this paper is to quantitatively evaluate nonlinear propagation effects of diagnostic ultrasound pulses in biological tissues and to assess whether a cellulose-based hydrogel can be a suitable material for tissue mimicking purposes. Hydrogel and pig liver tissue samples of various thicknesses were insonified in a through-transmission set-up, employing 2.25-MHz pulses with different mechanical index (MI) values (range 0.06-0.60). Second harmonic and first harmonic amplitudes were extracted from spectra of received signals and their ratio was then used to compare hydrogel and liver behaviours. Resulting trends are very similar for sample thicknesses up to 8 cm and highlight a significant increase in nonlinearity for MI > 0.3, for both liver and hydrogel. A numerical procedure was also employed to calculate pressure distribution along the beam axis: these theoretical results showed a very good agreement with experimental data in the low pressure range, though failed in predicting the MI threshold. In conclusion, the hydrogel resulted to be a suitable material for manufacturing tissue mimicking phantoms, in particular to study contrast agent behaviour with a "low power approach".

  6. Standardisation of digital human models.

    Science.gov (United States)

    Paul, Gunther; Wischniewski, Sascha

    2012-01-01

    Digital human models (DHM) have evolved as useful tools for ergonomic workplace design and product development, and found in various industries and education. DHM systems which dominate the market were developed for specific purposes and differ significantly, which is not only reflected in non-compatible results of DHM simulations, but also provoking misunderstanding of how DHM simulations relate to real world problems. While DHM developers are restricted by uncertainty about the user need and lack of model data related standards, users are confined to one specific product and cannot exchange results, or upgrade to another DHM system, as their previous results would be rendered worthless. Furthermore, origin and validity of anthropometric and biomechanical data is not transparent to the user. The lack of standardisation in DHM systems has become a major roadblock in further system development, affecting all stakeholders in the DHM industry. Evidently, a framework for standardising digital human models is necessary to overcome current obstructions. Practitioner Summary: This short communication addresses a standardisation issue for digital human models, which has been addressed at the International Ergonomics Association Technical Committee for Human Simulation and Virtual Environments. It is the outcome of a workshop at the DHM 2011 symposium in Lyon, which concluded steps towards DHM standardisation that need to be taken.

  7. Modelling biased human trust dynamics

    NARCIS (Netherlands)

    Hoogendoorn, M.; Jaffry, S.W.; Maanen, P.P. van; Treur, J.

    2013-01-01

    Abstract. Within human trust related behaviour, according to the literature from the domains of Psychology and Social Sciences often non-rational behaviour can be observed. Current trust models that have been developed typically do not incorporate non-rational elements in the trust formation

  8. Gastric Adenomyoma: The Unexpected Mimicker

    Directory of Open Access Journals (Sweden)

    Marcela Adriana Duran Álvarez

    2017-01-01

    Full Text Available Gastric adenomyoma is a rare benign tumor composed of epithelial structures and smooth muscle stroma. Here, we report an unusual case of gastric adenomyoma mostly composed of smooth muscle that was incidentally found during a laparoscopic intervention. On radiology, it mimicked an acquired hypertrophic pyloric stenosis in an adult patient, and pathologically it resembled a pure smooth muscle hamartoma. Complete submission of the lesion for histology was necessary to find the epithelial component and make the right diagnosis. As a mimicker of benign and malignant entities, gastric adenomyoma is usually an unexpected finding after surgery. The aim of this report is to analyze this adenomyoma variant in the setting of an unexplained thickening of the gastric wall, with explanations concerning histogenesis and biological potential.

  9. Multicystic Hepatocarcinoma Mimicking Liver Abscess

    Directory of Open Access Journals (Sweden)

    Evangelos Falidas

    2013-01-01

    Full Text Available The diagnosis of hepatocellular carcinoma (HCC became easier in relation to the improved radiological examinations; however, the neoplasm may occur under atypical presentations mimicking other benign or malignant processes. Multicystic HCC mimicking a liver abscess associated with septic-type fever and leukocytosis is rare, has a poor prognosis, and poses diagnostic and therapeutic dilemmas. We present the case of an 80-year-old patient, who presented with fever, leukocytosis, and large cystic masses involving right and left lobes of the liver initially considered abscesses and finally diagnosed as HCC after open drainage and liver biopsy. Although the patient died on the tenth postoperative day due to pulmonary oedema, the authors emphasize the high index of suspicion needed in the diagnosis of this unusual presentation of HCC.

  10. Tongue metastasis mimicking an abscess.

    Science.gov (United States)

    Mavili, Ertuğrul; Oztürk, Mustafa; Yücel, Tuba; Yüce, Imdat; Cağli, Sedat

    2010-03-01

    Primary tumors metastasizing to the oral cavity are extremely rare. Lung is one of the most common primary sources of metastases to the tongue. Although the incidence of lung cancer is increasing, tongue metastasis as the initial presentation of the tumor remains uncommon. Due to the rarity of tongue metastasis, little is known about its imaging findings. Herein we report the magnetic resonance imaging and clinical findings of a lingual metastasis, mimicking an abscess, from a primary lung cancer.

  11. Clozapine Intoxication Mimicking Acute Stroke

    Directory of Open Access Journals (Sweden)

    Joshua D. Villarreal

    2018-04-01

    Full Text Available Clozapine is an atypical antipsychotic drug prescribed for treatment-resistant schizophrenia. The risk of adverse hematologic, cardiovascular, and neurologic effects has tempered its use, and reports of overdoses remain rare. We report a case of accidental acute clozapine intoxication in a clozapine-naïve patient, who presented with symptoms mimicking acute stroke and later developed status epilepticus. Clozapine intoxication is a rare presentation in the emergency department with potential for iatrogenic harm if not correctly identified.

  12. Empirical modelling to predict the refractive index of human blood

    Science.gov (United States)

    Yahya, M.; Saghir, M. Z.

    2016-02-01

    Optical techniques used for the measurement of the optical properties of blood are of great interest in clinical diagnostics. Blood analysis is a routine procedure used in medical diagnostics to confirm a patient’s condition. Measuring the optical properties of blood is difficult due to the non-homogenous nature of the blood itself. In addition, there is a lot of variation in the refractive indices reported in the literature. These are the reasons that motivated the researchers to develop a mathematical model that can be used to predict the refractive index of human blood as a function of concentration, temperature and wavelength. The experimental measurements were conducted on mimicking phantom hemoglobin samples using the Abbemat Refractometer. The results analysis revealed a linear relationship between the refractive index and concentration as well as temperature, and a non-linear relationship between refractive index and wavelength. These results are in agreement with those found in the literature. In addition, a new formula was developed based on empirical modelling which suggests that temperature and wavelength coefficients be added to the Barer formula. The verification of this correlation confirmed its ability to determine refractive index and/or blood hematocrit values with appropriate clinical accuracy.

  13. Empirical modelling to predict the refractive index of human blood

    International Nuclear Information System (INIS)

    Yahya, M; Saghir, M Z

    2016-01-01

    Optical techniques used for the measurement of the optical properties of blood are of great interest in clinical diagnostics. Blood analysis is a routine procedure used in medical diagnostics to confirm a patient’s condition. Measuring the optical properties of blood is difficult due to the non-homogenous nature of the blood itself. In addition, there is a lot of variation in the refractive indices reported in the literature. These are the reasons that motivated the researchers to develop a mathematical model that can be used to predict the refractive index of human blood as a function of concentration, temperature and wavelength. The experimental measurements were conducted on mimicking phantom hemoglobin samples using the Abbemat Refractometer. The results analysis revealed a linear relationship between the refractive index and concentration as well as temperature, and a non-linear relationship between refractive index and wavelength. These results are in agreement with those found in the literature. In addition, a new formula was developed based on empirical modelling which suggests that temperature and wavelength coefficients be added to the Barer formula. The verification of this correlation confirmed its ability to determine refractive index and/or blood hematocrit values with appropriate clinical accuracy. (paper)

  14. Mathematical models of human behavior

    DEFF Research Database (Denmark)

    Møllgaard, Anders Edsberg

    at the Technical University of Denmark. The data set includes face-to-face interaction (Bluetooth), communication (calls and texts), mobility (GPS), social network (Facebook), and general background information including a psychological profile (questionnaire). This thesis presents my work on the Social Fabric...... data set, along with work on other behavioral data. The overall goal is to contribute to a quantitative understanding of human behavior using big data and mathematical models. Central to the thesis is the determination of the predictability of different human activities. Upper limits are derived....... Evidence is provided, which implies that the asymmetry is caused by a self-enhancement in the initiation dynamics. These results have implications for the formation of social networks and the dynamics of the links. It is shown that the Big Five Inventory (BFI) representing a psychological profile only...

  15. Human Thermal Model Evaluation Using the JSC Human Thermal Database

    Science.gov (United States)

    Bue, Grant; Makinen, Janice; Cognata, Thomas

    2012-01-01

    Human thermal modeling has considerable long term utility to human space flight. Such models provide a tool to predict crew survivability in support of vehicle design and to evaluate crew response in untested space environments. It is to the benefit of any such model not only to collect relevant experimental data to correlate it against, but also to maintain an experimental standard or benchmark for future development in a readily and rapidly searchable and software accessible format. The Human thermal database project is intended to do just so; to collect relevant data from literature and experimentation and to store the data in a database structure for immediate and future use as a benchmark to judge human thermal models against, in identifying model strengths and weakness, to support model development and improve correlation, and to statistically quantify a model s predictive quality. The human thermal database developed at the Johnson Space Center (JSC) is intended to evaluate a set of widely used human thermal models. This set includes the Wissler human thermal model, a model that has been widely used to predict the human thermoregulatory response to a variety of cold and hot environments. These models are statistically compared to the current database, which contains experiments of human subjects primarily in air from a literature survey ranging between 1953 and 2004 and from a suited experiment recently performed by the authors, for a quantitative study of relative strength and predictive quality of the models.

  16. Pre-university Chemistry Students in a Mimicked Scholarly Peer Review

    Science.gov (United States)

    van Rens, Lisette; Hermarij, Philip; Pilot, Albert; Beishuizen, Jos; Hofman, Herman; Wal, Marjolein

    2014-10-01

    Peer review is a significant component in scientific research. Introducing peer review into inquiry processes may be regarded as an aim to develop student understanding regarding quality in inquiries. This study examines student understanding in inquiry peer reviews among pre-university chemistry students, aged 16-17, when they enact a design of a mimicked scholarly peer review. This design is based on a model of a human activity system. Twenty-five different schools in Brazil, Germany, Poland and The Netherlands participated. The students (n = 880) conducted in small groups (n = 428) open inquiries on fermentation. All groups prepared an inquiry report for peer review. These reports were published on a website. Groups were randomly paired in an internet symposium, where they posted review comments to their peers. These responses were qualitatively analyzed on small groups' level of understanding regarding seven categories: inquiry question, hypothesis, management of control variables, accurate measurement, presenting results, reliability of results, discussion and conclusion. The mimicked scholarly review prompted a collective practice. Student understanding was significantly well on presenting results, discussion and conclusion, and significantly less on inquiry question and reliability of results. An enacted design, based on a model of a human activity system, created student understanding of quality in inquiries as well as an insight in a peer-reviewing practice. To what extent this model can be applied in a broader context of design research in science education needs further study.

  17. Tissue-Mimicking Geometrical Constraints Stimulate Tissue-Like Constitution and Activity of Mouse Neonatal and Human-Induced Pluripotent Stem Cell-Derived Cardiac Myocytes

    Directory of Open Access Journals (Sweden)

    Götz Pilarczyk

    2016-01-01

    Full Text Available The present work addresses the question of to what extent a geometrical support acts as a physiological determining template in the setup of artificial cardiac tissue. Surface patterns with alternating concave to convex transitions of cell size dimensions were used to organize and orientate human-induced pluripotent stem cell (hIPSC-derived cardiac myocytes and mouse neonatal cardiac myocytes. The shape of the cells, as well as the organization of the contractile apparatus recapitulates the anisotropic line pattern geometry being derived from tissue geometry motives. The intracellular organization of the contractile apparatus and the cell coupling via gap junctions of cell assemblies growing in a random or organized pattern were examined. Cell spatial and temporal coordinated excitation and contraction has been compared on plain and patterned substrates. While the α-actinin cytoskeletal organization is comparable to terminally-developed native ventricular tissue, connexin-43 expression does not recapitulate gap junction distribution of heart muscle tissue. However, coordinated contractions could be observed. The results of tissue-like cell ensemble organization open new insights into geometry-dependent cell organization, the cultivation of artificial heart tissue from stem cells and the anisotropy-dependent activity of therapeutic compounds.

  18. Vicarious Learning from Human Models in Monkeys

    OpenAIRE

    Falcone, Rossella; Brunamonti, Emiliano; Genovesio, Aldo

    2012-01-01

    We examined whether monkeys can learn by observing a human model, through vicarious learning. Two monkeys observed a human model demonstrating an object-reward association and consuming food found underneath an object. The monkeys observed human models as they solved more than 30 learning problems. For each problem, the human models made a choice between two objects, one of which concealed a piece of apple. In the test phase afterwards, the monkeys made a choice of their own. Learning was app...

  19. A Q fever case mimicking crimean-congo haemorrhagic fever

    Directory of Open Access Journals (Sweden)

    O Karabay

    2011-01-01

    Full Text Available Coxiella burnetii is the bacterium that causes Q fever. Human infection is mainly transmitted from cattle, goats and sheep. The disease is usually self-limited. Pneumonia and hepatitis are the most common clinical manifestations. In this study, we present a case of Q fever from the western part of Turkey mimicking Crimean-Congo haemorrhagic fever (CCHF in terms of clinical and laboratory findings.

  20. Vicarious learning from human models in monkeys.

    Science.gov (United States)

    Falcone, Rossella; Brunamonti, Emiliano; Genovesio, Aldo

    2012-01-01

    We examined whether monkeys can learn by observing a human model, through vicarious learning. Two monkeys observed a human model demonstrating an object-reward association and consuming food found underneath an object. The monkeys observed human models as they solved more than 30 learning problems. For each problem, the human models made a choice between two objects, one of which concealed a piece of apple. In the test phase afterwards, the monkeys made a choice of their own. Learning was apparent from the first trial of the test phase, confirming the ability of monkeys to learn by vicarious observation of human models.

  1. Vicarious learning from human models in monkeys.

    Directory of Open Access Journals (Sweden)

    Rossella Falcone

    Full Text Available We examined whether monkeys can learn by observing a human model, through vicarious learning. Two monkeys observed a human model demonstrating an object-reward association and consuming food found underneath an object. The monkeys observed human models as they solved more than 30 learning problems. For each problem, the human models made a choice between two objects, one of which concealed a piece of apple. In the test phase afterwards, the monkeys made a choice of their own. Learning was apparent from the first trial of the test phase, confirming the ability of monkeys to learn by vicarious observation of human models.

  2. Odontogenic Keratocyst Mimicking Paradental Cyst

    Directory of Open Access Journals (Sweden)

    Andrea Enrico Borgonovo

    2014-01-01

    Full Text Available Objective. The aim of this paper is to present an uncommon clinical and radiographic aspect of odontogenic keratocyst (OKC mimicking paradental cyst. Methods. A 32-year-old female patient showed a well-delimited radiolucent lesion connected with the root of the left third molar with close anatomical relationship with the mandibular canal. The clinical, radiographic, and anamnestic features lead us to diagnose a paradental cyst that was treated by enucleation after extraction of the partially impacted tooth. Results. Histological analysis showed typical histological features of PKC such as the presence of a lining of stratified squamous epithelium with a well-defined basal layer of palisading columnar of cuboidal cells. Conclusion. Initial X-ray analysis and the position of the lesion related to the third mandibular tooth caused us to mistakenly diagnose a paradental cyst. We were only able to identify the cyst as an PKC rather than a paradental cyst after histological analysis.

  3. Gout: radiographic findings mimicking infection

    International Nuclear Information System (INIS)

    Rousseau, I.; Raymond-Tremblay, D.; Cardinal, E.; Beauregard, C.G.; Braunstein, E.M.; Saint-Pierre, A.

    2001-01-01

    Objective: To describe radiographic features of gout that may mimic infection. Design and patients: We report five patients with acute bacterial gout who presented with clinical as well as radiological findings mimicking acute bacterial septic arthritis or osteomyelitis. Three patients had delay in the appropriate treatment with the final diagnosis being established after needle aspiration and identification of urate crystals under polarized light microscopy. Two patients underwent digit amputation for not responding to antibiotic treatment and had histological findings confirming the diagnosis of gout. Conclusion: It is important for the radiologist to be aware of the radiological manifestations of acute gout that can resemble infection in order to avoid inappropriate diagnosis and delay in adequate treatment. The definitive diagnosis should rely on needle aspiration and a specific search for urate crystals. (orig.)

  4. Sporadic naturally occurring melanoma in dogs as a preclinical model for human melanoma.

    Science.gov (United States)

    Simpson, R Mark; Bastian, Boris C; Michael, Helen T; Webster, Joshua D; Prasad, Manju L; Conway, Catherine M; Prieto, Victor M; Gary, Joy M; Goldschmidt, Michael H; Esplin, D Glen; Smedley, Rebecca C; Piris, Adriano; Meuten, Donald J; Kiupel, Matti; Lee, Chyi-Chia R; Ward, Jerrold M; Dwyer, Jennifer E; Davis, Barbara J; Anver, Miriam R; Molinolo, Alfredo A; Hoover, Shelley B; Rodriguez-Canales, Jaime; Hewitt, Stephen M

    2014-01-01

    Melanoma represents a significant malignancy in humans and dogs. Different from genetically engineered models, sporadic canine melanocytic neoplasms share several characteristics with human disease that could make dogs a more relevant preclinical model. Canine melanomas rarely arise in sun-exposed sites. Most occur in the oral cavity, with a subset having intra-epithelial malignant melanocytes mimicking the in situ component of human mucosal melanoma. The spectrum of canine melanocytic neoplasia includes benign lesions with some analogy to nevi, as well as invasive primary melanoma, and widespread metastasis. Growing evidence of distinct subtypes in humans, differing in somatic and predisposing germ-line genetic alterations, cell of origin, epidemiology, relationship to ultraviolet radiation and progression from benign to malignant tumors, may also exist in dogs. Canine and human mucosal melanomas appear to harbor BRAF, NRAS, and c-kit mutations uncommonly, compared with human cutaneous melanomas, although both species share AKT and MAPK signaling activation. We conclude that there is significant overlap in the clinical and histopathological features of canine and human mucosal melanomas. This represents opportunity to explore canine oral cavity melanoma as a preclinical model. © 2013 The Authors. Pigment Cell & Melanoma Research published by John Wiley & Sons Ltd.

  5. Human Performance Modeling for Dynamic Human Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Boring, Ronald Laurids [Idaho National Laboratory; Joe, Jeffrey Clark [Idaho National Laboratory; Mandelli, Diego [Idaho National Laboratory

    2015-08-01

    Part of the U.S. Department of Energy’s (DOE’s) Light Water Reac- tor Sustainability (LWRS) Program, the Risk-Informed Safety Margin Charac- terization (RISMC) Pathway develops approaches to estimating and managing safety margins. RISMC simulations pair deterministic plant physics models with probabilistic risk models. As human interactions are an essential element of plant risk, it is necessary to integrate human actions into the RISMC risk framework. In this paper, we review simulation based and non simulation based human reliability analysis (HRA) methods. This paper summarizes the founda- tional information needed to develop a feasible approach to modeling human in- teractions in RISMC simulations.

  6. Mouse Models of Diet-Induced Nonalcoholic Steatohepatitis Reproduce the Heterogeneity of the Human Disease

    Science.gov (United States)

    Machado, Mariana Verdelho; Michelotti, Gregory Alexander; Xie, Guanhua; de Almeida, Thiago Pereira; Boursier, Jerome; Bohnic, Brittany; Guy, Cynthia D.; Diehl, Anna Mae

    2015-01-01

    Background and aims Non-alcoholic steatohepatitis (NASH), the potentially progressive form of nonalcoholic fatty liver disease (NAFLD), is the pandemic liver disease of our time. Although there are several animal models of NASH, consensus regarding the optimal model is lacking. We aimed to compare features of NASH in the two most widely-used mouse models: methionine-choline deficient (MCD) diet and Western diet. Methods Mice were fed standard chow, MCD diet for 8 weeks, or Western diet (45% energy from fat, predominantly saturated fat, with 0.2% cholesterol, plus drinking water supplemented with fructose and glucose) for 16 weeks. Liver pathology and metabolic profile were compared. Results The metabolic profile associated with human NASH was better mimicked by Western diet. Although hepatic steatosis (i.e., triglyceride accumulation) was also more severe, liver non-esterified fatty acid content was lower than in the MCD diet group. NASH was also less severe and less reproducible in the Western diet model, as evidenced by less liver cell death/apoptosis, inflammation, ductular reaction, and fibrosis. Various mechanisms implicated in human NASH pathogenesis/progression were also less robust in the Western diet model, including oxidative stress, ER stress, autophagy deregulation, and hedgehog pathway activation. Conclusion Feeding mice a Western diet models metabolic perturbations that are common in humans with mild NASH, whereas administration of a MCD diet better models the pathobiological mechanisms that cause human NAFLD to progress to advanced NASH. PMID:26017539

  7. Mouse models of diet-induced nonalcoholic steatohepatitis reproduce the heterogeneity of the human disease.

    Directory of Open Access Journals (Sweden)

    Mariana Verdelho Machado

    Full Text Available Non-alcoholic steatohepatitis (NASH, the potentially progressive form of nonalcoholic fatty liver disease (NAFLD, is the pandemic liver disease of our time. Although there are several animal models of NASH, consensus regarding the optimal model is lacking. We aimed to compare features of NASH in the two most widely-used mouse models: methionine-choline deficient (MCD diet and Western diet.Mice were fed standard chow, MCD diet for 8 weeks, or Western diet (45% energy from fat, predominantly saturated fat, with 0.2% cholesterol, plus drinking water supplemented with fructose and glucose for 16 weeks. Liver pathology and metabolic profile were compared.The metabolic profile associated with human NASH was better mimicked by Western diet. Although hepatic steatosis (i.e., triglyceride accumulation was also more severe, liver non-esterified fatty acid content was lower than in the MCD diet group. NASH was also less severe and less reproducible in the Western diet model, as evidenced by less liver cell death/apoptosis, inflammation, ductular reaction, and fibrosis. Various mechanisms implicated in human NASH pathogenesis/progression were also less robust in the Western diet model, including oxidative stress, ER stress, autophagy deregulation, and hedgehog pathway activation.Feeding mice a Western diet models metabolic perturbations that are common in humans with mild NASH, whereas administration of a MCD diet better models the pathobiological mechanisms that cause human NAFLD to progress to advanced NASH.

  8. Berberine Improves Intestinal Motility and Visceral Pain in the Mouse Models Mimicking Diarrhea-Predominant Irritable Bowel Syndrome (IBS-D Symptoms in an Opioid-Receptor Dependent Manner.

    Directory of Open Access Journals (Sweden)

    Chunqiu Chen

    Full Text Available Berberine and its derivatives display potent analgesic, anti-inflammatory and anticancer activity. Here we aimed at characterizing the mechanism of action of berberine in the gastrointestinal (GI tract and cortical neurons using animal models and in vitro tests.The effect of berberine was characterized in murine models mimicking diarrhea-predominant irritable bowel syndrome (IBS-D symptoms. Then the opioid antagonists were used to identify the receptors involved. Furthermore, the effect of berberineon opioid receptors expression was established in the mouse intestine and rat fetal cortical neurons.In mouse models, berberine prolonged GI transit and time to diarrhea in a dose-dependent manner, and significantly reduced visceral pain. In physiological conditions the effects of berberine were mediated by mu- (MOR and delta- (DOR opioid receptors; hypermotility, excessive secretion and nociception were reversed by berberine through MOR and DOR-dependent action. We also found that berberine increased the expression of MOR and DOR in the mouse bowel and rat fetal cortical neurons.Berberine significantly improved IBS-D symptoms in animal models, possibly through mu- and delta- opioid receptors. Berberine may become a new drug candidate for the successful treatment of IBS-D in clinical conditions.

  9. Bone tumor mimickers: A pictorial essay

    International Nuclear Information System (INIS)

    Mhuircheartaigh, Jennifer Ni; Lin, Yu-Ching; Wu, Jim S

    2014-01-01

    Focal lesions in bone are very common and many of these lesions are not bone tumors. These bone tumor mimickers can include numerous normal anatomic variants and non-neoplastic processes. Many of these tumor mimickers can be left alone, while others can be due to a significant disease process. It is important for the radiologist and clinician to be aware of these bone tumor mimickers and understand the characteristic features which allow discrimination between them and true neoplasms in order to avoid unnecessary additional workup. Knowing which lesions to leave alone or which ones require workup can prevent misdiagnosis and reduce patient anxiety

  10. Subaortic membrane mimicking hypertrophic cardiomyopathy.

    Science.gov (United States)

    Anderson, Mark Joseph; Arruda-Olson, Adelaide; Gersh, Bernard; Geske, Jeffrey

    2015-11-04

    A 34-year-old man was referred for progressive angina and exertional dyspnoea refractory to medical therapy, with a presumptive diagnosis of hypertrophic cardiomyopathy (HCM). Transthoracic echocardiography (TTE) revealed asymmetric septal hypertrophy without systolic anterior motion of the mitral valve leaflet and with no dynamic left ventricular outflow tract (LVOT) obstruction. However, the LVOT velocity was elevated at rest as well as with provocation, without the characteristic late peaking obstruction seen in HCM. Focused TTE to evaluate for suspected fixed obstruction demonstrated a subaortic membrane 2.2 cm below the aortic valve. Coronary CT angiography confirmed the presence of the subaortic membrane and was negative for concomitant coronary artery disease. Surgical resection of the subaortic membrane and septal myectomy resulted in significant symptomatic relief and lower LVOT velocities on postoperative TTE. This case reminds the clinician to carefully evaluate for alternative causes of LVOT obstruction, especially subaortic membrane, as a cause of symptoms mimicking HCM. 2015 BMJ Publishing Group Ltd.

  11. Tracheobronchial Amyloidosis Mimicking Tracheal Tumor

    Directory of Open Access Journals (Sweden)

    Elif Tanrıverdi

    2016-01-01

    Full Text Available Tracheobronchial amyloidosis is a rare presentation and accounts for about 1% of benign tumors in this area. The diagnosis of disease is delayed due to nonspecific pulmonary symptoms. Therapeutic approaches are required to control progressive pulmonary symptoms for most of the patients. Herein, we report a case of a 68-year-old man admitted with progressive dyspnea to our institution for further evaluation and management. He was initially diagnosed with and underwent management for bronchial asthma for two years but had persistent symptoms despite optimal medical therapy. Pulmonary computed tomography scan revealed severe endotracheal stenosis. Bronchoscopy was performed and showed endotracheal mass obstructing 70% of the distal trachea and mimicking a neoplastic lesion. The mass was successfully resected by mechanical resection, argon plasma coagulation (APC, and Nd-YAG laser during rigid bronchoscopy. Biopsy materials showed deposits of amorphous material by hematoxylin and eosin staining and these deposits were selectively stained with Congo Red. Although this is a rare clinical condition, this case indicated that carrying out a bronchoscopy in any patient complaining of atypical bronchial symptoms or with uncontrolled asthma is very important.

  12. Leiomyoma of the distal oesophagus mimicking achalasia

    NARCIS (Netherlands)

    Idenburg, F. J.; Akkermans, L. M.; Smout, A. J.; Kooijman, C. D.; Obertop, H.

    1991-01-01

    An unusual case of a patient with symptoms suggestive of oesophageal achalasia is described. Most oesophageal tumour growths causing secondary achalasia are associated with malignant tumours. This patient had a large oesophageal leiomyoma closely mimicking achalasia. Treatment consisted of

  13. Modeling of Embedded Human Systems

    Science.gov (United States)

    2013-07-01

    ISAT study [7] for DARPA in 20051 concretized the notion of an embedded human, who is a necessary component of the system. The proposed work integrates...Technology, IEEE Transactions on, vol. 16, no. 2, pp. 229–244, March 2008. [7] C. J. Tomlin and S. S. Sastry, “Embedded humans,” tech. rep., DARPA ISAT

  14. On scaling of human body models

    Directory of Open Access Journals (Sweden)

    Hynčík L.

    2007-10-01

    Full Text Available Human body is not an unique being, everyone is another from the point of view of anthropometry and mechanical characteristics which means that division of the human body population to categories like 5%-tile, 50%-tile and 95%-tile from the application point of view is not enough. On the other hand, the development of a particular human body model for all of us is not possible. That is why scaling and morphing algorithms has started to be developed. The current work describes the development of a tool for scaling of the human models. The idea is to have one (or couple of standard model(s as a base and to create other models based on these basic models. One has to choose adequate anthropometrical and biomechanical parameters that describe given group of humans to be scaled and morphed among.

  15. Stress, overeating, and obesity: Insights from human studies and preclinical models.

    Science.gov (United States)

    Razzoli, Maria; Pearson, Carolyn; Crow, Scott; Bartolomucci, Alessandro

    2017-05-01

    Eating disorders and obesity have become predominant in human society. Their association to modern lifestyle, encompassing calorie-rich diets, psychological stress, and comorbidity with major diseases are well documented. Unfortunately the biological basis remains elusive and the pharmacological treatment inadequate, in part due to the limited availability of valid animal models. Human research on binge eating disorder (BED) proves a strong link between stress exposure and bingeing: state-levels of stress and negative affect are linked to binge eating in individuals with BED both in laboratory settings and the natural environment. Similarly, classical animal models of BED reveal an association between acute exposure to stressors and binging but they are often associated with unchanged or decreased body weight, thus reflecting a negative energy balance, which is uncommon in humans where most commonly BED is associated with excessive or unstable body weight gain. Recent mouse models of subordination stress induce spontaneous binging and hyperphagia, altogether more closely mimicking the behavioral and metabolic features of human BED. Therefore the translational relevance of subordination stress models could facilitate the identification of the neurobiological basis of BED and obesity-associated disease and inform on the development of innovative therapies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Giant hydronephrosis mimicking progressive malignancy

    Science.gov (United States)

    Schrader, Andres Jan; Anderer, Georgia; von Knobloch, Rolf; Heidenreich, Axel; Hofmann, Rainer

    2003-01-01

    Background Cases of giant hydronephroses are rare and usually contain no more than 1–2 litres of fluid in the collecting system. We report a remarkable case of giant hydronephrosis mimicking a progressive malignant abdominal tumour. Case presentation A 78-year-old cachectic woman presented with an enormous abdominal tumour, which, according to the patient, had slowly increased in diameter. Medical history was unremarkable except for a hysterectomy >30 years before. A CT scan revealed a giant cystic tumour filling almost the entire abdominal cavity. It was analysed by two independent radiologists who suspected a tumour originating from the right kidney and additionally a cystic ovarian neoplasm. Subsequently, a diagnostic and therapeutic laparotomy was performed: the tumour presented as a cystic, 35 × 30 × 25 cm expansive structure adhesive to adjacent organs without definite signs of invasive growth. The right renal hilar vessels could finally be identified at its basis. After extirpation another tumourous structure emerged in the pelvis originating from the genital organs and was also resected. The histopathological examination revealed a >15 kg hydronephrotic right kidney, lacking hardly any residual renal cortex parenchyma. The second specimen was identified as an ovary with regressive changes and a large partially calcified cyst. There was no evidence of malignant growth. Conclusion Although both clinical symptoms and the enormous size of the tumour indicated malignant growth, it turned out to be a giant hydronephrosis. Presumably, a chronic obstruction of the distal ureter had caused this extraordinary hydronephrosis. As demonstrated in our case, an accurate diagnosis of giant hydronephrosis remains challenging due to the atrophy of the renal parenchyma associated with chronic obstruction. Therefore, any abdominal cystic mass even in the absence of other evident pathologies should include the differential diagnosis of a possible hydronephrosis. Diagnostic

  17. Modeling multimodal human-computer interaction

    NARCIS (Netherlands)

    Obrenovic, Z.; Starcevic, D.

    2004-01-01

    Incorporating the well-known Unified Modeling Language into a generic modeling framework makes research on multimodal human-computer interaction accessible to a wide range off software engineers. Multimodal interaction is part of everyday human discourse: We speak, move, gesture, and shift our gaze

  18. Hidden Markov Models for Human Genes

    DEFF Research Database (Denmark)

    Baldi, Pierre; Brunak, Søren; Chauvin, Yves

    1997-01-01

    We analyse the sequential structure of human genomic DNA by hidden Markov models. We apply models of widely different design: conventional left-right constructs and models with a built-in periodic architecture. The models are trained on segments of DNA sequences extracted such that they cover com...

  19. On quantum models of the human mind.

    Science.gov (United States)

    Wang, Hongbin; Sun, Yanlong

    2014-01-01

    Recent years have witnessed rapidly increasing interests in developing quantum theoretical models of human cognition. Quantum mechanisms have been taken seriously to describe how the mind reasons and decides. Papers in this special issue report the newest results in the field. Here we discuss why the two levels of commitment, treating the human brain as a quantum computer and merely adopting abstract quantum probability principles to model human cognition, should be integrated. We speculate that quantum cognition models gain greater modeling power due to a richer representation scheme. Copyright © 2013 Cognitive Science Society, Inc.

  20. Cascading walks model for human mobility patterns.

    Science.gov (United States)

    Han, Xiao-Pu; Wang, Xiang-Wen; Yan, Xiao-Yong; Wang, Bing-Hong

    2015-01-01

    Uncovering the mechanism behind the scaling laws and series of anomalies in human trajectories is of fundamental significance in understanding many spatio-temporal phenomena. Recently, several models, e.g. the explorations-returns model (Song et al., 2010) and the radiation model for intercity travels (Simini et al., 2012), have been proposed to study the origin of these anomalies and the prediction of human movements. However, an agent-based model that could reproduce most of empirical observations without priori is still lacking. In this paper, considering the empirical findings on the correlations of move-lengths and staying time in human trips, we propose a simple model which is mainly based on the cascading processes to capture the human mobility patterns. In this model, each long-range movement activates series of shorter movements that are organized by the law of localized explorations and preferential returns in prescribed region. Based on the numerical simulations and analytical studies, we show more than five statistical characters that are well consistent with the empirical observations, including several types of scaling anomalies and the ultraslow diffusion properties, implying the cascading processes associated with the localized exploration and preferential returns are indeed a key in the understanding of human mobility activities. Moreover, the model shows both of the diverse individual mobility and aggregated scaling displacements, bridging the micro and macro patterns in human mobility. In summary, our model successfully explains most of empirical findings and provides deeper understandings on the emergence of human mobility patterns.

  1. Human Centered Hardware Modeling and Collaboration

    Science.gov (United States)

    Stambolian Damon; Lawrence, Brad; Stelges, Katrine; Henderson, Gena

    2013-01-01

    In order to collaborate engineering designs among NASA Centers and customers, to in clude hardware and human activities from multiple remote locations, live human-centered modeling and collaboration across several sites has been successfully facilitated by Kennedy Space Center. The focus of this paper includes innovative a pproaches to engineering design analyses and training, along with research being conducted to apply new technologies for tracking, immersing, and evaluating humans as well as rocket, vehic le, component, or faci lity hardware utilizing high resolution cameras, motion tracking, ergonomic analysis, biomedical monitoring, wor k instruction integration, head-mounted displays, and other innovative human-system integration modeling, simulation, and collaboration applications.

  2. Human Adaptive Mechatronics and Human-System Modelling

    Directory of Open Access Journals (Sweden)

    Satoshi Suzuki

    2013-03-01

    Full Text Available Several topics in projects for mechatronics studies, which are 'Human Adaptive Mechatronics (HAM' and 'Human-System Modelling (HSM', are presented in this paper. The main research theme of the HAM project is a design strategy for a new intelligent mechatronics system, which enhances operators' skills during machine operation. Skill analyses and control system design have been addressed. In the HSM project, human modelling based on hierarchical classification of skills was studied, including the following five types of skills: social, planning, cognitive, motion and sensory-motor skills. This paper includes digests of these research topics and the outcomes concerning each type of skill. Relationships with other research activities, knowledge and information that will be helpful for readers who are trying to study assistive human-mechatronics systems are also mentioned.

  3. Mimicking the effect of gravity using an elastic membrane

    International Nuclear Information System (INIS)

    Wu, Yecun; Zhu, Changqing; Wang, Yijun; Shi, Qingfan

    2014-01-01

    Comparing astrospace with an elastic membrane is an interesting analogy but it lacks a theoretical basis and experimental support. We develop a theoretical model that brings to light the relationship between the conceptual model of a gravity well and an elastic deformation equation of a membrane supporting a heavy ball, and further derive the ‘gravitational constant’ for such a small ‘elastic space’. The experimental data obtained are consistent with the prediction of our model, in mimicking the revolution of a small planet. Teaching practice shows that using an elastic membrane is a simple, intuitive and reliable method to enhance the quality of learning about the effect of gravity. (paper)

  4. Mimicking the action of folding chaperones by Hamiltonian replica-exchange molecular dynamics simulations : Application in the refinement of de novo models

    NARCIS (Netherlands)

    Fan, Hao; Periole, Xavier; Mark, Alan E.

    The efficiency of using a variant of Hamiltonian replica-exchange molecular dynamics (Chaperone H-replica-exchange molecular dynamics [CH-REMD]) for the refinement of protein structural models generated de novo is investigated. In CH-REMD, the interaction between the protein and its environment,

  5. Modelling human factor with Petri nets

    International Nuclear Information System (INIS)

    Bedreaga, Luminita; Constantinescu, Cristina; Guzun, Basarab

    2007-01-01

    The human contribution to risk and safety of nuclear power plant operation can be best understood, assessed and quantified using tools to evaluate human reliability. Human reliability analysis becomes an important part of every probabilistic safety assessment and it is used to demonstrate that nuclear power plants designed with different safety levels are prepared to cope with severe accidents. Human reliability analysis in context of probabilistic safety assessment consists in: identifying human-system interactions important to safety; quantifying probabilities appropriate with these interactions. Nowadays, the complex system functions can be modelled using special techniques centred either on states space adequate to system or on events appropriate to the system. Knowing that complex system model consists in evaluating the likelihood of success, in other words, in evaluating the possible value for that system being in some state, the inductive methods which are based on the system states can be applied also for human reliability modelling. Thus, switching to the system states taking into account the human interactions, the underlying basis of the Petri nets can be successfully applied and the likelihoods appropriate to these states can also derived. The paper presents the manner to assess the human reliability quantification using Petri nets approach. The example processed in the paper is from human reliability documentation without a detailed human factor analysis (qualitative). The obtained results by these two kinds of methods are in good agreement. (authors)

  6. Experimental human-like model to assess the part of viable Legionella reaching the thoracic region after nebulization.

    Directory of Open Access Journals (Sweden)

    Jérémie Pourchez

    Full Text Available The incidence of Legionnaires' disease (LD in European countries and the USA has been constantly increasing since 1998. Infection of humans occurs through aerosol inhalation. To bridge the existing gap between the concentration of Legionella in a water network and the deposition of bacteria within the thoracic region (assessment of the number of viable Legionella, we validated a model mimicking realistic exposure through the use of (i recent technology for aerosol generation and (ii a 3D replicate of the human upper respiratory tract. The model's sensitivity was determined by monitoring the deposition of (i aerosolized water and Tc99m radio-aerosol as controls, and (ii bioaerosols generated from both Escherichia coli and Legionella pneumophila sg 1 suspensions. The numbers of viable Legionella prior to and after nebulization were provided by culture, flow cytometry and qPCR. This study was designed to obtain more realistic data on aerosol inhalation (vs. animal experimentation and deposition at the thoracic region in the context of LD. Upon nebulization, 40% and 48% of the initial Legionella inoculum was made of cultivable and non-cultivable cells, respectively; 0.7% of both populations reached the filter holder mimicking the thoracic region in this setup. These results are in agreement with experimental data based on quantitative microbial risk assessment methods and bring new methods that may be useful for preventing LD.

  7. Modeling human disease using organotypic cultures

    DEFF Research Database (Denmark)

    Schweiger, Pawel J; Jensen, Kim B

    2016-01-01

    animal models and in vitro cell culture systems. However, it has been exceedingly difficult to model disease at the tissue level. Since recently, the gap between cell line studies and in vivo modeling has been narrowing thanks to progress in biomaterials and stem cell research. Development of reliable 3D...... culture systems has enabled a rapid expansion of sophisticated in vitro models. Here we focus on some of the latest advances and future perspectives in 3D organoids for human disease modeling....

  8. Modeling Human Elements of Decision-Making

    Science.gov (United States)

    2002-06-01

    include factors such as personality, emotion , and level of expertise, which vary from individual to individual. The process of decision - making during... rational choice theories such as utility theory, to more descriptive psychological models that focus more on the process of decision - making ...descriptive nature, they provide a more realistic representation of human decision - making than the rationally based models. However these models do

  9. Comparative inhibitory effects of Thymus vulgaris L. essential oil against Staphylococcus aureus, Listeria monocytogenes and mesophilic starter co-culture in cheese-mimicking models.

    Science.gov (United States)

    de Carvalho, Rayssa Julliane; de Souza, Geanny Targino; Honório, Vanessa Gonçalves; de Sousa, Jossana Pereira; da Conceição, Maria Lúcia; Maganani, Marciane; de Souza, Evandro Leite

    2015-12-01

    In the present study, we assessed the effects of Thymus vulgaris L. essential oil (TVEO) on Staphylococcus aureus and Listeria monocytogenes, pathogenic bacteria frequently associated with fresh or low-ripened cheeses (e.g., Brazilian coalho cheese), and on a starter co-culture comprising Lactococcus lactis subsp. lactis and L. lactis subsp. cremoris, which are commonly used for the production of different cheeses. To measure these effects, we determined the minimum inhibitory concentration (MIC) and assessed bacterial cell viability over time in (coalho) cheese-based broth and in a semi-solid (coalho) cheese model at 10 °C. The MIC for TVEO was 2.5 μL/mL against S. aureus and L. monocytogenes, while the MIC was 1.25 μL/mL against the starter co-culture. The TVEO (5 and 2.5 μL/mL) sharply reduced the viable counts of all assayed bacteria in cheese broth over 24 h; although, at 5 μL/mL, TVEO more severely affected the viability of the starter co-culture compared with pathogenic bacteria. The addition of 1.25 μL/g of TVEO in the semi-solid cheese model did not reduce the viable counts of all assayed bacteria. At 2.5 μL/g, TVEO slightly decreased the viable counts of S. aureus, L. monocytogenes and Lactococcus spp. in the semi-solid cheese model over 72 h. The final counts of Lactococcus spp. in a semi-solid cheese model containing 2.5 μL/mL TVEO were lower than those of pathogenic bacteria under the same conditions. These results suggest that the doses of TVEO used to control pathogenic bacteria in fermented dairy products, especially in low-ripened cheeses, should be cautiously considered for potential negative effects on the growth and survival of starter cultures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Animal models for human genetic diseases

    African Journals Online (AJOL)

    Sharif Sons

    The study of human genetic diseases can be greatly aided by animal models because of their similarity .... and gene targeting in embryonic stem cells) has been a powerful tool in .... endonucleases that are designed to make a doublestrand.

  11. Human BDCM Mulit-Route PBPK Model

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data set contains the code for the BDCM human multi-route model written in the programming language acsl. The final published manuscript is provided since it...

  12. Effect of Temperature-Sensitive Poloxamer Solution/Gel Material on Pericardial Adhesion Prevention: Supine Rabbit Model Study Mimicking Cardiac Surgery.

    Directory of Open Access Journals (Sweden)

    Hyun Kang

    Full Text Available We investigated the mobility of a temperature-sensitive poloxamer/Alginate/CaCl2 mixture (PACM in relation to gravity and cardiac motion and the efficacy of PACM on the prevention of pericardial adhesion in a supine rabbit model.A total of 50 rabbits were randomly divided into two groups according to materials applied after epicardial abrasion: PACM and dye mixture (group PD; n = 25 and saline as the control group (group CO; n = 25. In group PD, rabbits were maintained in a supine position with appropriate sedation, and location of mixture of PACM and dye was assessed by CT scan at the immediate postoperative period and 12 hours after surgery. The grade of adhesions was evaluated macroscopically and microscopically two weeks after surgery.In group PD, enhancement was localized in the anterior pericardial space, where PACM and dye mixture was applied, on immediate post-surgical CT scans. However, the volume of the enhancement was significantly decreased at the anterior pericardial space 12 hours later (P < .001. Two weeks after surgery, group PD had significantly lower macroscopic adhesion score (P = .002 and fibrosis score (P = .018 than did group CO. Inflammation score and expression of anti-macrophage antibody in group PD were lower than those in group CO, although the differences were not significant.In a supine rabbit model study, the anti-adhesion effect was maintained at the area of PACM application, although PACM shifted with gravity and heart motion. For more potent pericardial adhesion prevention, further research and development on the maintenance of anti-adhesion material position are required.

  13. Human physiological models of insomnia.

    Science.gov (United States)

    Richardson, Gary S

    2007-12-01

    Despite the wide prevalence and important consequences of insomnia, remarkably little is known about its pathophysiology. Available models exist primarily in the psychological domain and derive from the demonstrated efficacy of behavioral treatment approaches to insomnia management. However, these models offer little specific prediction about the anatomic or physiological foundation of chronic primary insomnia. On the other hand, a growing body of data on the physiology of sleep supports a reasonably circumscribed overview of possible pathophysiological mechanisms, as well as the development of physiological models of insomnia to guide future research. As a pragmatic step, these models focus on primary insomnia, as opposed to comorbid insomnias, because the latter is by its nature a much more heterogeneous presentation, reflecting the effects of the distinct comorbid condition. Current understanding of the regulation of sleep and wakefulness in mammalian brain supports four broad candidate areas: 1) disruption of the sleep homeostat; 2) disruption of the circadian clock; 3) disruption of intrinsic systems responsible for the expression of sleep states; or 4) disruption (hyperactivity) of extrinsic systems capable of over-riding normal sleep-wake regulation. This review examines each of the four candidate pathophysiological mechanisms and the available data in support of each. While studies that directly test the viability of each model are not yet available, descriptive data on primary insomnia favor the involvement of dysfunctional extrinsic stress-response systems in the pathology of primary chronic insomnia.

  14. Modeling Human Cancers in Drosophila.

    Science.gov (United States)

    Sonoshita, M; Cagan, R L

    2017-01-01

    Cancer is a complex disease that affects multiple organs. Whole-body animal models provide important insights into oncology that can lead to clinical impact. Here, we review novel concepts that Drosophila studies have established for cancer biology, drug discovery, and patient therapy. Genetic studies using Drosophila have explored the roles of oncogenes and tumor-suppressor genes that when dysregulated promote cancer formation, making Drosophila a useful model to study multiple aspects of transformation. Not limited to mechanism analyses, Drosophila has recently been showing its value in facilitating drug development. Flies offer rapid, efficient platforms by which novel classes of drugs can be identified as candidate anticancer leads. Further, we discuss the use of Drosophila as a platform to develop therapies for individual patients by modeling the tumor's genetic complexity. Drosophila provides both a classical and a novel tool to identify new therapeutics, complementing other more traditional cancer tools. © 2017 Elsevier Inc. All rights reserved.

  15. The Human-Artifact Model

    DEFF Research Database (Denmark)

    Bødker, Susanne; Klokmose, Clemens Nylandsted

    2011-01-01

    Although devices of all shapes and sizes currently dominate the technological landscape, human–computer interaction (HCI) as a field is not yet theoretically equipped to match this reality. In this article we develop the human–artifact model, which has its roots in activity theoretical HCI....... By reinterpreting the activity theoretical foundation, we present a framework that helps addressing the analysis of individual interactive artifacts while embracing that they are part of a larger ecology of artifacts. We show how the human–artifact model helps structuring the understanding of an artifact's action......-possibilities in relation to the artifact ecology surrounding it. Essential to the model is that it provides four interconnected levels of analysis and addresses the possibilities and problems at these four levels. Artifacts and their use are constantly developing, and we address development in, and of, use. The framework...

  16. Modeling Human Information Acquisition Strategies

    NARCIS (Netherlands)

    Heuvelink, Annerieke; Klein, Michel C. A.; van Lambalgen, Rianne; Taatgen, Niels A.; Rijn, Hedderik van

    2009-01-01

    The focus of this paper is the development of a computational model for intelligent agents that decides on whether to acquire required information by retrieving it from memory or by interacting with the world. First, we present a task for which such decisions have to be made. Next, we discuss an

  17. Personality Model in Human Resources Management

    OpenAIRE

    Jovan Zubovic

    2008-01-01

    This paper presents the new „Personality model” of managing human resources in an organisation. The model analyses administrative personnel (usually called management) in an organisation and divides them into three core categories: managers, executives and advisors. Unlike traditional models which do not recognise advisors as part of an organisation, this model gives to advisors the same ranking as managers and executives. Model traces 11 categories of personality traits for every employee, r...

  18. Computational Intelligence in a Human Brain Model

    Directory of Open Access Journals (Sweden)

    Viorel Gaftea

    2016-06-01

    Full Text Available This paper focuses on the current trends in brain research domain and the current stage of development of research for software and hardware solutions, communication capabilities between: human beings and machines, new technologies, nano-science and Internet of Things (IoT devices. The proposed model for Human Brain assumes main similitude between human intelligence and the chess game thinking process. Tactical & strategic reasoning and the need to follow the rules of the chess game, all are very similar with the activities of the human brain. The main objective for a living being and the chess game player are the same: securing a position, surviving and eliminating the adversaries. The brain resolves these goals, and more, the being movement, actions and speech are sustained by the vital five senses and equilibrium. The chess game strategy helps us understand the human brain better and easier replicate in the proposed ‘Software and Hardware’ SAH Model.

  19. Animal Models of Human Placentation - A Review

    DEFF Research Database (Denmark)

    Carter, Anthony Michael

    2007-01-01

    This review examines the strengths and weaknesses of animal models of human placentation and pays particular attention to the mouse and non-human primates. Analogies can be drawn between mouse and human in placental cell types and genes controlling placental development. There are, however...... and delivers poorly developed young. Guinea pig is a good alternative rodent model and among the few species known to develop pregnancy toxaemia. The sheep is well established as a model in fetal physiology but is of limited value for placental research. The ovine placenta is epitheliochorial...... and endometrium is similar in macaques and baboons, as is the subsequent lacunar stage. The absence of interstitial trophoblast cells in the monkey is an important difference from human placentation. However, there is a strong resemblance in the way spiral arteries are invaded and transformed in the macaque...

  20. Iliacus Abscess with Radiculopathy Mimicking Herniated Nucleus ...

    African Journals Online (AJOL)

    2016-05-02

    May 2, 2016 ... radiculopathy mimicking herniated nucleus pulposus: Aadditional diagnostic value of magnetic resonance imaging. Niger J Clin Pract. 2017;20:392-3. This is an open access article distributed under the terms of the Creative Commons. Attribution-Non Commercial-Share Alike 3.0 License, which allows ...

  1. A statistical model of future human actions

    International Nuclear Information System (INIS)

    Woo, G.

    1992-02-01

    A critical review has been carried out of models of future human actions during the long term post-closure period of a radioactive waste repository. Various Markov models have been considered as alternatives to the standard Poisson model, and the problems of parameterisation have been addressed. Where the simplistic Poisson model unduly exaggerates the intrusion risk, some form of Markov model may have to be introduced. This situation may well arise for shallow repositories, but it is less likely for deep repositories. Recommendations are made for a practical implementation of a computer based model and its associated database. (Author)

  2. A Model of the Human Eye

    Science.gov (United States)

    Colicchia, G.; Wiesner, H.; Waltner, C.; Zollman, D.

    2008-01-01

    We describe a model of the human eye that incorporates a variable converging lens. The model can be easily constructed by students with low-cost materials. It shows in a comprehensible way the functionality of the eye's optical system. Images of near and far objects can be focused. Also, the defects of near and farsighted eyes can be demonstrated.

  3. Models of the Human in Tantric Hinduism

    DEFF Research Database (Denmark)

    Olesen, Bjarne Wernicke; Flood, Gavin

    2019-01-01

    This research project explores the origins, developments and transformations of yogic models of the human (e.g. kuṇḍalinī yoga, the cakra system and ritual sex) in the tantric goddess traditions or what might be called Śāktism of medieval India. These Śākta models of esoteric anatomy originating...

  4. Modeling human learning involved in car driving

    NARCIS (Netherlands)

    Wewerinke, P.H.

    1994-01-01

    In this paper, car driving is considered at the level of human tracking and maneuvering in the context of other traffic. A model analysis revealed the most salient features determining driving performance and safety. Learning car driving is modelled based on a system theoretical approach and based

  5. Mathematical human body modelling for impact loading

    NARCIS (Netherlands)

    Happee, R.; Morsink, P.L.J.; Wismans, J.S.H.M.

    1999-01-01

    Mathematical modelling of the human body is widely used for automotive crash safety research and design. Simulations have contributed to a reduction of injury numbers by optimisation of vehicle structures and restraint systems. Currently such simulations are largely performed using occupant models

  6. Human butyrylcholinesterase polymorphism: Molecular modeling.

    Science.gov (United States)

    Lushchekina, S; Delacour, H; Lockridge, O; Masson, P

    2015-01-01

    Prolonged apnoea following injection of ester-containing myoralaxants was first described in 1953. Because a large part of administered succinylcholine is shortly hydrolyzed by plasma butyrylcholinesterase (BChE) under normal conditions, prolonged apnoea was attributed to deficiency in BChE. It was found that BChE deficiency was due to genetic variations. Human BChE gene shows a large polyallelism. About 75 natural mutations of the BCHE gene have been documented so far [1]. Most of them cause alteration in BChE activity through point mutation effect on catalytic activity. Frame shifts and stop codons may also affect expression, or cause truncations in the sequence. Recently, two novel BChE "silent" variants, Val204Asp [2] and Ala34Val [3], causing prolonged neuromuscular block after administration of mivacurium, were discovered. Mutations were genetically and kinetically characterized. The aim of the current study was to understand how these mutations determine "silent" phenotype. Molecular dynamics studies were carried out with NAMD 2.9 software at the Lomonosov supercomputer. Charmm 36 force field was used, periodical boundary conditions, 1 atm pressure, 298 K. 100 ns molecular dynamics runs were performed for the wild-type BChE and its mutants Val204Asp and Ala34Val. Unlike wild-type BChE, which retained its operative catalytic triad through the whole MD simulation, the catalytic triad of mutants was disrupted, making chemical step impossible. Val204Asp mutation leads to reorganization of hydrogen bonding network around the catalytic triad, which in turn increases the distance between catalytic residue main chains. Mutation Ala34Val, located on the protein surface, leads to increased fluctuations in the Ω-loop and subsequent disruption of the gorge structure, including disruption of the catalytic triad and formation of new hydrogen bonds involving catalytic center residues. Comparative study of the "silent" Ala328Asp mutant and the catalytically active mutant

  7. Humanized Mouse Models of Staphylococcus aureus Infection

    Directory of Open Access Journals (Sweden)

    Dane Parker

    2017-05-01

    Full Text Available Staphylococcus aureus is a successful human pathogen that has adapted itself in response to selection pressure by the human immune system. A commensal of the human skin and nose, it is a leading cause of several conditions: skin and soft tissue infection, pneumonia, septicemia, peritonitis, bacteremia, and endocarditis. Mice have been used extensively in all these conditions to identify virulence factors and host components important for pathogenesis. Although significant effort has gone toward development of an anti-staphylococcal vaccine, antibodies have proven ineffective in preventing infection in humans after successful studies in mice. These results have raised questions as to the utility of mice to predict patient outcome and suggest that humanized mice might prove useful in modeling infection. The development of humanized mouse models of S. aureus infection will allow us to assess the contribution of several human-specific virulence factors, in addition to exploring components of the human immune system in protection against S. aureus infection. Their use is discussed in light of several recently reported studies.

  8. Human models of acute lung injury

    Directory of Open Access Journals (Sweden)

    Alastair G. Proudfoot

    2011-03-01

    Full Text Available Acute lung injury (ALI is a syndrome that is characterised by acute inflammation and tissue injury that affects normal gas exchange in the lungs. Hallmarks of ALI include dysfunction of the alveolar-capillary membrane resulting in increased vascular permeability, an influx of inflammatory cells into the lung and a local pro-coagulant state. Patients with ALI present with severe hypoxaemia and radiological evidence of bilateral pulmonary oedema. The syndrome has a mortality rate of approximately 35% and usually requires invasive mechanical ventilation. ALI can follow direct pulmonary insults, such as pneumonia, or occur indirectly as a result of blood-borne insults, commonly severe bacterial sepsis. Although animal models of ALI have been developed, none of them fully recapitulate the human disease. The differences between the human syndrome and the phenotype observed in animal models might, in part, explain why interventions that are successful in models have failed to translate into novel therapies. Improved animal models and the development of human in vivo and ex vivo models are therefore required. In this article, we consider the clinical features of ALI, discuss the limitations of current animal models and highlight how emerging human models of ALI might help to answer outstanding questions about this syndrome.

  9. Conceptual modelling of human resource evaluation process

    Directory of Open Access Journals (Sweden)

    Negoiţă Doina Olivia

    2017-01-01

    Full Text Available Taking into account the highly diverse tasks which employees have to fulfil due to complex requirements of nowadays consumers, the human resource within an enterprise has become a strategic element for developing and exploiting products which meet the market expectations. Therefore, organizations encounter difficulties when approaching the human resource evaluation process. Hence, the aim of the current paper is to design a conceptual model of the aforementioned process, which allows the enterprises to develop a specific methodology. In order to design the conceptual model, Business Process Modelling instruments were employed - Adonis Community Edition Business Process Management Toolkit using the ADONIS BPMS Notation. The conceptual model was developed based on an in-depth secondary research regarding the human resource evaluation process. The proposed conceptual model represents a generic workflow (sequential and/ or simultaneously activities, which can be extended considering the enterprise’s needs regarding their requirements when conducting a human resource evaluation process. Enterprises can benefit from using software instruments for business process modelling as they enable process analysis and evaluation (predefined / specific queries and also model optimization (simulations.

  10. Modeled microgravity suppressed invasion and migration of human glioblastoma U87 cells through downregulating store-operated calcium entry

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Zi-xuan [Department of Traditional Chinese Medicine, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 (China); Rao, Wei [Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 (China); Wang, Huan [Department of Dermatology, Tangdu Hospital, Fourth Military Medical University, Xi' an, 710032 (China); Wang, Nan-ding [Department of Cardiology, Xi' an Traditional Chinese Medicine Hospital, Xi' an, 710032 (China); Si, Jing-Wen; Zhao, Jiao; Li, Jun-chang [Department of Traditional Chinese Medicine, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 (China); Wang, Zong-ren, E-mail: zongren@fmmu.edu.cn [Department of Traditional Chinese Medicine, Xijing Hospital, Fourth Military Medical University, Xi' an, 710032 (China)

    2015-02-13

    Glioblastoma is the most common brain tumor and is characterized with robust invasion and migration potential resulting in poor prognosis. Previous investigations have demonstrated that modeled microgravity (MMG) could decline the cell proliferation and attenuate the metastasis potential in several cell lines. In this study, we studied the effects of MMG on the invasion and migration potentials of glioblastoma in human glioblastoma U87 cells. We found that MMG stimulation significantly attenuated the invasion and migration potentials, decreased thapsigargin (TG) induced store-operated calcium entry (SOCE) and downregulated the expression of Orai1 in U87 cells. Inhibition of SOCE by 2-APB or stromal interaction molecule 1 (STIM1) downregulation both mimicked the effects of MMG on the invasion and migration potentials in U87 cells. Furthermore, upregulation of Orai1 significantly weakened the effects of MMG on the invasion and migration potentials in U87 cells. Therefore, these findings indicated that MMG stimulation inhibited the invasion and migration potentials of U87 cells by downregulating the expression of Orai1 and sequentially decreasing the SOCE, suggesting that MMG might be a new potential therapeutic strategy in glioblastoma treatment in the future. - Highlights: • Modeled microgravity (MMG) suppressed migration and invasion in U87 cells. • MMG downregulated the SOCE and the expression of Orai1. • SOCE inhibition mimicked the effects of MMG on migration and invasion potentials. • Restoration of SOCE diminished the effects of MMG on migration and invasion.

  11. Modeled microgravity suppressed invasion and migration of human glioblastoma U87 cells through downregulating store-operated calcium entry

    International Nuclear Information System (INIS)

    Shi, Zi-xuan; Rao, Wei; Wang, Huan; Wang, Nan-ding; Si, Jing-Wen; Zhao, Jiao; Li, Jun-chang; Wang, Zong-ren

    2015-01-01

    Glioblastoma is the most common brain tumor and is characterized with robust invasion and migration potential resulting in poor prognosis. Previous investigations have demonstrated that modeled microgravity (MMG) could decline the cell proliferation and attenuate the metastasis potential in several cell lines. In this study, we studied the effects of MMG on the invasion and migration potentials of glioblastoma in human glioblastoma U87 cells. We found that MMG stimulation significantly attenuated the invasion and migration potentials, decreased thapsigargin (TG) induced store-operated calcium entry (SOCE) and downregulated the expression of Orai1 in U87 cells. Inhibition of SOCE by 2-APB or stromal interaction molecule 1 (STIM1) downregulation both mimicked the effects of MMG on the invasion and migration potentials in U87 cells. Furthermore, upregulation of Orai1 significantly weakened the effects of MMG on the invasion and migration potentials in U87 cells. Therefore, these findings indicated that MMG stimulation inhibited the invasion and migration potentials of U87 cells by downregulating the expression of Orai1 and sequentially decreasing the SOCE, suggesting that MMG might be a new potential therapeutic strategy in glioblastoma treatment in the future. - Highlights: • Modeled microgravity (MMG) suppressed migration and invasion in U87 cells. • MMG downregulated the SOCE and the expression of Orai1. • SOCE inhibition mimicked the effects of MMG on migration and invasion potentials. • Restoration of SOCE diminished the effects of MMG on migration and invasion

  12. Mechanical model of human eye compliance for volumetric occlusion break surge measurements.

    Science.gov (United States)

    Dyk, David W; Miller, Kevin M

    2018-02-01

    To develop a mechanical model of human eye compliance for volumetric studies. Alcon Research, Ltd., Lake Forest, California, USA. Experimental study. Enucleated human eyes underwent pressurization and depressurization cycles with peak intraocular pressures (IOPs) of 60 to 100 mm Hg; anterior chamber pressure and volume changes were measured. Average net volume change curves were calculated as a function of IOP for each eye. Overall mean volumes were computed from each eye's average results at pressure points extrapolated over the range of 5 to 90 mm Hg. A 2-term exponential function was fit to these results. A fluid chamber with a displaceable piston was created as a mechanical model of this equation. A laser confocal displacement meter was used to measure piston displacement. A test bed incorporated the mechanical model with a mounted phacoemulsification probe and allowed for simulated occlusion breaks. Surge volume was calculated from piston displacement. An exponential function, V = C 1 × exp(C 2 × IOP) + C 3  × exp(C 4  × IOP) - V 0 , where V, the volume, was fit to the final depressurization curve obtained from 15 enucleated human eyes. The C 1 through C 4 values were -0.07141, -0.23055, -0.14972, and -0.02006, respectively. The equation was modeled using a piston system with 3 parallel springs that engaged serially. The mechanical model mimicked depressurization curves observed in human cadaver eyes. The resulting mechanical compliance model measured ocular volumetric changes and thus would be helpful in characterizing the postocclusion break surge response. Copyright © 2018 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  13. Mouse Chromosome Engineering for Modeling Human Disease

    OpenAIRE

    van der Weyden, Louise; Bradley, Allan

    2006-01-01

    Chromosomal rearrangements occur frequently in humans and can be disease-associated or phenotypically neutral. Recent technological advances have led to the discovery of copy-number changes previously undetected by cytogenetic techniques. To understand the genetic consequences of such genomic changes, these mutations need to be modeled in experimentally tractable systems. The mouse is an excellent organism for this analysis because of its biological and genetic similarity to humans, and the e...

  14. CGRP in human models of primary headaches

    DEFF Research Database (Denmark)

    Ashina, Håkan; Schytz, Henrik Winther; Ashina, Messoud

    2018-01-01

    experiments are likely due to assay variation; therefore, proper validation and standardization of an assay is needed. To what extent CGRP is involved in tension-type headache and cluster headache is unknown. CONCLUSION: Human models of primary headaches have elucidated the role of CGRP in headache...... pathophysiology and sparked great interest in developing new treatment strategies using CGRP antagonists and antibodies. Future studies applying more refined human experimental models should identify biomarkers of CGRP-induced primary headache and reveal whether CGRP provocation experiments could be used......OBJECTIVE: To review the role of CGRP in human models of primary headaches and to discuss methodological aspects and future directions. DISCUSSION: Provocation experiments demonstrated a heterogeneous CGRP migraine response in migraine patients. Conflicting CGRP plasma results in the provocation...

  15. Animal and human models to understand ageing.

    Science.gov (United States)

    Lees, Hayley; Walters, Hannah; Cox, Lynne S

    2016-11-01

    Human ageing is the gradual decline in organ and tissue function with increasing chronological time, leading eventually to loss of function and death. To study the processes involved over research-relevant timescales requires the use of accessible model systems that share significant similarities with humans. In this review, we assess the usefulness of various models, including unicellular yeasts, invertebrate worms and flies, mice and primates including humans, and highlight the benefits and possible drawbacks of each model system in its ability to illuminate human ageing mechanisms. We describe the strong evolutionary conservation of molecular pathways that govern cell responses to extracellular and intracellular signals and which are strongly implicated in ageing. Such pathways centre around insulin-like growth factor signalling and integration of stress and nutritional signals through mTOR kinase. The process of cellular senescence is evaluated as a possible underlying cause for many of the frailties and diseases of human ageing. Also considered is ageing arising from systemic changes that cannot be modelled in lower organisms and instead require studies either in small mammals or in primates. We also touch briefly on novel therapeutic options arising from a better understanding of the biology of ageing. Copyright © 2016. Published by Elsevier Ireland Ltd.

  16. Identification of walking human model using agent-based modelling

    Science.gov (United States)

    Shahabpoor, Erfan; Pavic, Aleksandar; Racic, Vitomir

    2018-03-01

    The interaction of walking people with large vibrating structures, such as footbridges and floors, in the vertical direction is an important yet challenging phenomenon to describe mathematically. Several different models have been proposed in the literature to simulate interaction of stationary people with vibrating structures. However, the research on moving (walking) human models, explicitly identified for vibration serviceability assessment of civil structures, is still sparse. In this study, the results of a comprehensive set of FRF-based modal tests were used, in which, over a hundred test subjects walked in different group sizes and walking patterns on a test structure. An agent-based model was used to simulate discrete traffic-structure interactions. The occupied structure modal parameters found in tests were used to identify the parameters of the walking individual's single-degree-of-freedom (SDOF) mass-spring-damper model using 'reverse engineering' methodology. The analysis of the results suggested that the normal distribution with the average of μ = 2.85Hz and standard deviation of σ = 0.34Hz can describe human SDOF model natural frequency. Similarly, the normal distribution with μ = 0.295 and σ = 0.047 can describe the human model damping ratio. Compared to the previous studies, the agent-based modelling methodology proposed in this paper offers significant flexibility in simulating multi-pedestrian walking traffics, external forces and simulating different mechanisms of human-structure and human-environment interaction at the same time.

  17. Generative models of the human connectome.

    Science.gov (United States)

    Betzel, Richard F; Avena-Koenigsberger, Andrea; Goñi, Joaquín; He, Ye; de Reus, Marcel A; Griffa, Alessandra; Vértes, Petra E; Mišic, Bratislav; Thiran, Jean-Philippe; Hagmann, Patric; van den Heuvel, Martijn; Zuo, Xi-Nian; Bullmore, Edward T; Sporns, Olaf

    2016-01-01

    The human connectome represents a network map of the brain's wiring diagram and the pattern into which its connections are organized is thought to play an important role in cognitive function. The generative rules that shape the topology of the human connectome remain incompletely understood. Earlier work in model organisms has suggested that wiring rules based on geometric relationships (distance) can account for many but likely not all topological features. Here we systematically explore a family of generative models of the human connectome that yield synthetic networks designed according to different wiring rules combining geometric and a broad range of topological factors. We find that a combination of geometric constraints with a homophilic attachment mechanism can create synthetic networks that closely match many topological characteristics of individual human connectomes, including features that were not included in the optimization of the generative model itself. We use these models to investigate a lifespan dataset and show that, with age, the model parameters undergo progressive changes, suggesting a rebalancing of the generative factors underlying the connectome across the lifespan. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Modeling the exergy behavior of human body

    International Nuclear Information System (INIS)

    Keutenedjian Mady, Carlos Eduardo; Silva Ferreira, Maurício; Itizo Yanagihara, Jurandir; Hilário Nascimento Saldiva, Paulo; Oliveira Junior, Silvio de

    2012-01-01

    Exergy analysis is applied to assess the energy conversion processes that take place in the human body, aiming at developing indicators of health and performance based on the concepts of exergy destroyed rate and exergy efficiency. The thermal behavior of the human body is simulated by a model composed of 15 cylinders with elliptical cross section representing: head, neck, trunk, arms, forearms, hands, thighs, legs, and feet. For each, a combination of tissues is considered. The energy equation is solved for each cylinder, being possible to obtain transitory response from the body due to a variation in environmental conditions. With this model, it is possible to obtain heat and mass flow rates to the environment due to radiation, convection, evaporation and respiration. The exergy balances provide the exergy variation due to heat and mass exchange over the body, and the exergy variation over time for each compartments tissue and blood, the sum of which leads to the total variation of the body. Results indicate that exergy destroyed and exergy efficiency decrease over lifespan and the human body is more efficient and destroys less exergy in lower relative humidities and higher temperatures. -- Highlights: ► In this article it is indicated an overview of the human thermal model. ► It is performed the energy and exergy analysis of the human body. ► Exergy destruction and exergy efficiency decreases with lifespan. ► Exergy destruction and exergy efficiency are a function of environmental conditions.

  19. Bayesian Modeling of a Human MMORPG Player

    Science.gov (United States)

    Synnaeve, Gabriel; Bessière, Pierre

    2011-03-01

    This paper describes an application of Bayesian programming to the control of an autonomous avatar in a multiplayer role-playing game (the example is based on World of Warcraft). We model a particular task, which consists of choosing what to do and to select which target in a situation where allies and foes are present. We explain the model in Bayesian programming and show how we could learn the conditional probabilities from data gathered during human-played sessions.

  20. Jack Human Modelling Tool: A Review

    Science.gov (United States)

    2010-01-01

    design and evaluation [8] and evolved into the Computerised Biomechanical Man Model (Combiman), shown in Figure 2. Combiman was developed at the...unrealistic arrangement of tetrahedra (Figure 7) to a highly realistic human model based on current anthropometric, anatomical and biomechanical data...has long legs and a short torso may find it difficult to adjust the seat and rudder pedals to achieve the required over the nose vision, reach to

  1. Modeling human intention formation for human reliability assessment

    International Nuclear Information System (INIS)

    Woods, D.D.; Roth, E.M.; Pople, H. Jr.

    1988-01-01

    This paper describes a dynamic simulation capability for modeling how people form intentions to act in nuclear power plant emergency situations. This modeling tool, Cognitive Environment Simulation or CES, was developed based on techniques from artificial intelligence. It simulates the cognitive processes that determine situation assessment and intention formation. It can be used to investigate analytically what situations and factors lead to intention failures, what actions follow from intention failures (e.g. errors of omission, errors of commission, common mode errors), the ability to recover from errors or additional machine failures, and the effects of changes in the NPP person machine system. One application of the CES modeling environment is to enhance the measurement of the human contribution to risk in probabilistic risk assessment studies. (author)

  2. Modelling dengue epidemic spreading with human mobility

    Science.gov (United States)

    Barmak, D. H.; Dorso, C. O.; Otero, M.

    2016-04-01

    We explored the effect of human mobility on the spatio-temporal dynamics of Dengue with a stochastic model that takes into account the epidemiological dynamics of the infected mosquitoes and humans, with different mobility patterns of the human population. We observed that human mobility strongly affects the spread of infection by increasing the final size and by changing the morphology of the epidemic outbreaks. When the spreading of the disease is driven only by mosquito dispersal (flight), a main central focus expands diffusively. On the contrary, when human mobility is taken into account, multiple foci appear throughout the evolution of the outbreaks. These secondary foci generated throughout the outbreaks could be of little importance according to their mass or size compared with the largest main focus. However, the coalescence of these foci with the main one generates an effect, through which the latter develops a size greater than the one obtained in the case driven only by mosquito dispersal. This increase in growth rate due to human mobility and the coalescence of the foci are particularly relevant in temperate cities such as the city of Buenos Aires, since they give more possibilities to the outbreak to grow before the arrival of the low-temperature season. The findings of this work indicate that human mobility could be the main driving force in the dynamics of vector epidemics.

  3. Invasive Aspergillosis Mimicking Metastatic Lung Cancer

    Directory of Open Access Journals (Sweden)

    Michiel J. E. G. W. Vanfleteren

    2018-06-01

    Full Text Available In a patient with a medical history of cancer, the most probable diagnosis of an 18FDG-avid pulmonary mass combined with intracranial abnormalities on brain imaging is metastasized cancer. However, sometimes a differential diagnosis with an infectious cause such as aspergillosis can be very challenging as both cancer and infection are sometimes difficult to distinguish. Pulmonary aspergillosis can present as an infectious pseudotumour with clinical and imaging characteristics mimicking lung cancer. Even in the presence of cerebral lesions, radiological appearance of abscesses can look like brain metastasis. These similarities can cause significant diagnostic difficulties with a subsequent therapeutic delay and a potential adverse outcome. Awareness of this infectious disease that can mimic lung cancer, even in an immunocompetent patient, is important. We report a case of a 65-year-old woman with pulmonary aspergillosis disseminated to the brain mimicking metastatic lung cancer.

  4. Modeling and Simulating Virtual Anatomical Humans

    NARCIS (Netherlands)

    Madehkhaksar, Forough; Luo, Zhiping; Pronost, Nicolas; Egges, Arjan

    2014-01-01

    This chapter presents human musculoskeletal modeling and simulation as a challenging field that lies between biomechanics and computer animation. One of the main goals of computer animation research is to develop algorithms and systems that produce plausible motion. On the other hand, the main

  5. Intracranial capillary hemangioma mimicking a dissociative disorder

    Directory of Open Access Journals (Sweden)

    Alexander Lacasse

    2012-01-01

    Full Text Available Capillary hemangiomas, hamartomatous proliferation of vascular endothelial cells, are rare in the central nervous system (CNS. Intracranial capillary hemangiomas presenting with reversible behavioral abnormalities and focal neurological deficits have rarely been reported. We report a case of CNS capillary hemangioma presenting with transient focal neurological deficits and behavioral abnormalities mimicking Ganser’s syndrome. Patient underwent total excision of the vascular malformation, resulting in complete resolution of his symptoms.

  6. Intra-abdominal gout mimicking pelvic abscess

    International Nuclear Information System (INIS)

    Chen, Chia-Hui; Chen, Clement Kuen-Huang; Yeh, Lee-Ren; Pan, Huay-Ban; Yang, Chien-Fang

    2005-01-01

    Gout is the most common crystal-induced arthritis. Gouty tophi typically deposit in the extremities, especially toes and fingers. We present an unusual case of intrapelvic tophaceous gout in a patient suffering from chronic gouty arthritis. CT and MRI of the abdomen and pelvic cavity disclosed calcified gouty tophi around both hips, and a cystic lesion with peripheral enhancement in the pelvic cavity along the course of the iliopsoas muscle. The intra-abdominal tophus mimicked pelvic abscess. (orig.)

  7. Intra-abdominal gout mimicking pelvic abscess

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chia-Hui; Chen, Clement Kuen-Huang [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung (Taiwan); National Yang-Ming University, School of Medicine, Taipei (Taiwan); Yeh, Lee-Ren; Pan, Huay-Ban; Yang, Chien-Fang [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung (Taiwan)

    2005-04-01

    Gout is the most common crystal-induced arthritis. Gouty tophi typically deposit in the extremities, especially toes and fingers. We present an unusual case of intrapelvic tophaceous gout in a patient suffering from chronic gouty arthritis. CT and MRI of the abdomen and pelvic cavity disclosed calcified gouty tophi around both hips, and a cystic lesion with peripheral enhancement in the pelvic cavity along the course of the iliopsoas muscle. The intra-abdominal tophus mimicked pelvic abscess. (orig.)

  8. Mycobacterium intracellulare Infection Mimicking Progression of Scleroderma

    DEFF Research Database (Denmark)

    Krabbe, Simon; Engelhart, Merete; Thybo, Sören

    2017-01-01

    This case report describes a patient with scleroderma who developed Mycobacterium intracellulare infection, which for more than a year mimicked worsening of her connective tissue disorder. The patient was diagnosed with scleroderma based on puffy fingers that developed into sclerodactyly, abnormal......, unfortunately with significant scarring. Immunodeficiency testing was unremarkable. In summary, an infection with Mycobacterium intracellulare was mistaken for an unusually severe progression of scleroderma....

  9. Orthokeratinised odontogenic cyst mimicking periapical cyst

    OpenAIRE

    Rajalakshmi, R; Sreeja, C; Vijayalakshmi, D; Leelarani, V

    2013-01-01

    Orthokeratinised odontogenic cyst (OOC) denotes the odontogenic cyst that microscopically has an orthokeratinised epithelial lining. OOC is characterised by a less-aggressive behaviour and a low rate of recurrence. This report describes a case of OOC involving posterior part of the mandible that mimicked periapical cyst in a 14-year-old boy. The initial clinical diagnosis was given as periapical cyst based on the clinical and radiographical features. Enucleation of the cyst was performed and ...

  10. Optical models of the human eye.

    Science.gov (United States)

    Atchison, David A; Thibos, Larry N

    2016-03-01

    Optical models of the human eye have been used in visual science for purposes such as providing a framework for explaining optical phenomena in vision, for predicting how refraction and aberrations are affected by change in ocular biometry and as computational tools for exploring the limitations imposed on vision by the optical system of the eye. We address the issue of what is understood by optical model eyes, discussing the 'encyclopaedia' and 'toy train' approaches to modelling. An extensive list of purposes of models is provided. We discuss many of the theoretical types of optical models (also schematic eyes) of varying anatomical accuracy, including single, three and four refracting surface variants. We cover the models with lens structure in the form of nested shells and gradient index. Many optical eye models give accurate predictions only for small angles and small fields of view. If aberrations and image quality are important to consider, such 'paraxial' model eyes must be replaced by 'finite model' eyes incorporating features such as aspheric surfaces, tilts and decentrations, wavelength-dependent media and curved retinas. Many optical model eyes are population averages and must become adaptable to account for age, gender, ethnicity, refractive error and accommodation. They can also be customised for the individual when extensive ocular biometry and optical performance data are available. We consider which optical model should be used for a particular purpose, adhering to the principle that the best model is the simplest fit for the task. We provide a glimpse into the future of optical models of the human eye. This review is interwoven with historical developments, highlighting the important people who have contributed so richly to our understanding of visual optics. © 2016 The Authors. Clinical and Experimental Optometry © 2016 Optometry Australia.

  11. Modeling human infertility with pluripotent stem cells

    Directory of Open Access Journals (Sweden)

    Di Chen

    2017-05-01

    Full Text Available Human fertility is dependent upon the correct establishment and differentiation of the germline. This is because no other cell type in the body is capable of passing a genome and epigenome from parent to child. Terminally differentiated germline cells in the adult testis and ovary are called gametes. However, the initial specification of germline cells occurs in the embryo around the time of gastrulation. Most of our knowledge regarding the cell and molecular events that govern human germline specification involves extrapolating scientific principles from model organisms, most notably the mouse. However, recent work using next generation sequencing, gene editing and differentiation of germline cells from pluripotent stem cells has revealed that the core molecular mechanisms that regulate human germline development are different from rodents. Here, we will discuss the major molecular pathways required for human germline differentiation and how pluripotent stem cells have revolutionized our ability to study the earliest steps in human embryonic lineage specification in order to understand human fertility.

  12. Development of a realistic human airway model.

    Science.gov (United States)

    Lizal, Frantisek; Elcner, Jakub; Hopke, Philip K; Jedelsky, Jan; Jicha, Miroslav

    2012-03-01

    Numerous models of human lungs with various levels of idealization have been reported in the literature; consequently, results acquired using these models are difficult to compare to in vivo measurements. We have developed a set of model components based on realistic geometries, which permits the analysis of the effects of subsequent model simplification. A realistic digital upper airway geometry except for the lack of an oral cavity has been created which proved suitable both for computational fluid dynamics (CFD) simulations and for the fabrication of physical models. Subsequently, an oral cavity was added to the tracheobronchial geometry. The airway geometry including the oral cavity was adjusted to enable fabrication of a semi-realistic model. Five physical models were created based on these three digital geometries. Two optically transparent models, one with and one without the oral cavity, were constructed for flow velocity measurements, two realistic segmented models, one with and one without the oral cavity, were constructed for particle deposition measurements, and a semi-realistic model with glass cylindrical airways was developed for optical measurements of flow velocity and in situ particle size measurements. One-dimensional phase doppler anemometry measurements were made and compared to the CFD calculations for this model and good agreement was obtained.

  13. Modeling Individual Cyclic Variation in Human Behavior.

    Science.gov (United States)

    Pierson, Emma; Althoff, Tim; Leskovec, Jure

    2018-04-01

    Cycles are fundamental to human health and behavior. Examples include mood cycles, circadian rhythms, and the menstrual cycle. However, modeling cycles in time series data is challenging because in most cases the cycles are not labeled or directly observed and need to be inferred from multidimensional measurements taken over time. Here, we present Cyclic Hidden Markov Models (CyH-MMs) for detecting and modeling cycles in a collection of multidimensional heterogeneous time series data. In contrast to previous cycle modeling methods, CyHMMs deal with a number of challenges encountered in modeling real-world cycles: they can model multivariate data with both discrete and continuous dimensions; they explicitly model and are robust to missing data; and they can share information across individuals to accommodate variation both within and between individual time series. Experiments on synthetic and real-world health-tracking data demonstrate that CyHMMs infer cycle lengths more accurately than existing methods, with 58% lower error on simulated data and 63% lower error on real-world data compared to the best-performing baseline. CyHMMs can also perform functions which baselines cannot: they can model the progression of individual features/symptoms over the course of the cycle, identify the most variable features, and cluster individual time series into groups with distinct characteristics. Applying CyHMMs to two real-world health-tracking datasets-of human menstrual cycle symptoms and physical activity tracking data-yields important insights including which symptoms to expect at each point during the cycle. We also find that people fall into several groups with distinct cycle patterns, and that these groups differ along dimensions not provided to the model. For example, by modeling missing data in the menstrual cycles dataset, we are able to discover a medically relevant group of birth control users even though information on birth control is not given to the model.

  14. Modeling Operations Costs for Human Exploration Architectures

    Science.gov (United States)

    Shishko, Robert

    2013-01-01

    Operations and support (O&S) costs for human spaceflight have not received the same attention in the cost estimating community as have development costs. This is unfortunate as O&S costs typically comprise a majority of life-cycle costs (LCC) in such programs as the International Space Station (ISS) and the now-cancelled Constellation Program. Recognizing this, the Constellation Program and NASA HQs supported the development of an O&S cost model specifically for human spaceflight. This model, known as the Exploration Architectures Operations Cost Model (ExAOCM), provided the operations cost estimates for a variety of alternative human missions to the moon, Mars, and Near-Earth Objects (NEOs) in architectural studies. ExAOCM is philosophically based on the DoD Architecture Framework (DoDAF) concepts of operational nodes, systems, operational functions, and milestones. This paper presents some of the historical background surrounding the development of the model, and discusses the underlying structure, its unusual user interface, and lastly, previous examples of its use in the aforementioned architectural studies.

  15. Computer Modeling of Human Delta Opioid Receptor

    Directory of Open Access Journals (Sweden)

    Tatyana Dzimbova

    2013-04-01

    Full Text Available The development of selective agonists of δ-opioid receptor as well as the model of interaction of ligands with this receptor is the subjects of increased interest. In the absence of crystal structures of opioid receptors, 3D homology models with different templates have been reported in the literature. The problem is that these models are not available for widespread use. The aims of our study are: (1 to choose within recently published crystallographic structures templates for homology modeling of the human δ-opioid receptor (DOR; (2 to evaluate the models with different computational tools; and (3 to precise the most reliable model basing on correlation between docking data and in vitro bioassay results. The enkephalin analogues, as ligands used in this study, were previously synthesized by our group and their biological activity was evaluated. Several models of DOR were generated using different templates. All these models were evaluated by PROCHECK and MolProbity and relationship between docking data and in vitro results was determined. The best correlations received for the tested models of DOR were found between efficacy (erel of the compounds, calculated from in vitro experiments and Fitness scoring function from docking studies. New model of DOR was generated and evaluated by different approaches. This model has good GA341 value (0.99 from MODELLER, good values from PROCHECK (92.6% of most favored regions and MolProbity (99.5% of favored regions. Scoring function correlates (Pearson r = -0.7368, p-value = 0.0097 with erel of a series of enkephalin analogues, calculated from in vitro experiments. So, this investigation allows suggesting a reliable model of DOR. Newly generated model of DOR receptor could be used further for in silico experiments and it will give possibility for faster and more correct design of selective and effective ligands for δ-opioid receptor.

  16. Human physiologically based pharmacokinetic model for propofol

    Directory of Open Access Journals (Sweden)

    Schnider Thomas W

    2005-04-01

    Full Text Available Abstract Background Propofol is widely used for both short-term anesthesia and long-term sedation. It has unusual pharmacokinetics because of its high lipid solubility. The standard approach to describing the pharmacokinetics is by a multi-compartmental model. This paper presents the first detailed human physiologically based pharmacokinetic (PBPK model for propofol. Methods PKQuest, a freely distributed software routine http://www.pkquest.com, was used for all the calculations. The "standard human" PBPK parameters developed in previous applications is used. It is assumed that the blood and tissue binding is determined by simple partition into the tissue lipid, which is characterized by two previously determined set of parameters: 1 the value of the propofol oil/water partition coefficient; 2 the lipid fraction in the blood and tissues. The model was fit to the individual experimental data of Schnider et. al., Anesthesiology, 1998; 88:1170 in which an initial bolus dose was followed 60 minutes later by a one hour constant infusion. Results The PBPK model provides a good description of the experimental data over a large range of input dosage, subject age and fat fraction. Only one adjustable parameter (the liver clearance is required to describe the constant infusion phase for each individual subject. In order to fit the bolus injection phase, for 10 or the 24 subjects it was necessary to assume that a fraction of the bolus dose was sequestered and then slowly released from the lungs (characterized by two additional parameters. The average weighted residual error (WRE of the PBPK model fit to the both the bolus and infusion phases was 15%; similar to the WRE for just the constant infusion phase obtained by Schnider et. al. using a 6-parameter NONMEM compartmental model. Conclusion A PBPK model using standard human parameters and a simple description of tissue binding provides a good description of human propofol kinetics. The major advantage of a

  17. [A giant myxoid leiomyoma mimicking an inguinal hernia].

    Science.gov (United States)

    Huszár, Orsolya; Zaránd, Attila; Szántó, Gyöngyi; Juhász, Viktória; Székely, Eszter; Novák, András; Molnár, Béla Ákos; Harsányi, László

    2016-03-06

    Leiomyoma is a rare, smooth muscle tumour that can occur everywhere in the human body. The authors present the history of a 60-year-old female, who had a giant, Mullerian type myxoid leiomyoma in the inguinal region mimicking acute abdominal symptoms. After examination the authors removed the soft tissue mass in the right femoral region reaching down in supine position to the middle third of the leg measuring 335 × 495 × 437 mm in greatest diameters in weight 33 kg. Reconstruction of the tissue defect was performed using oncoplastic guidelines. During the follow-up time no tumour recurrence was detected and the quality of life of the patient improved significantly.

  18. Human Plague Risk: Spatial-Temporal Models

    Science.gov (United States)

    Pinzon, Jorge E.

    2010-01-01

    This chpater reviews the use of spatial-temporal models in identifying potential risks of plague outbreaks into the human population. Using earth observations by satellites remote sensing there has been a systematic analysis and mapping of the close coupling between the vectors of the disease and climate variability. The overall result is that incidence of plague is correlated to positive El Nino/Southem Oscillation (ENSO).

  19. MODELING HUMAN RELIABILITY ANALYSIS USING MIDAS

    Energy Technology Data Exchange (ETDEWEB)

    Ronald L. Boring; Donald D. Dudenhoeffer; Bruce P. Hallbert; Brian F. Gore

    2006-05-01

    This paper summarizes an emerging collaboration between Idaho National Laboratory and NASA Ames Research Center regarding the utilization of high-fidelity MIDAS simulations for modeling control room crew performance at nuclear power plants. The key envisioned uses for MIDAS-based control room simulations are: (i) the estimation of human error with novel control room equipment and configurations, (ii) the investigative determination of risk significance in recreating past event scenarios involving control room operating crews, and (iii) the certification of novel staffing levels in control rooms. It is proposed that MIDAS serves as a key component for the effective modeling of risk in next generation control rooms.

  20. Towards the establishment of a porcine model to study human amebiasis.

    Directory of Open Access Journals (Sweden)

    Fabienne Girard-Misguich

    Full Text Available BACKGROUND: Entamoeba histolytica is an important parasite of the human intestine. Its life cycle is monoxenous with two stages: (i the trophozoite, growing in the intestine and (ii the cyst corresponding to the dissemination stage. The trophozoite in the intestine can live as a commensal leading to asymptomatic infection or as a tissue invasive form producing mucosal ulcers and liver abscesses. There is no animal model mimicking the whole disease cycle. Most of the biological information on E. histolytica has been obtained from trophozoite adapted to axenic culture. The reproduction of intestinal amebiasis in an animal model is difficult while for liver amebiasis there are well-described rodent models. During this study, we worked on the assessment of pigs as a new potential model to study amebiasis. METHODOLOGY/PRINCIPAL FINDINGS: We first co-cultured trophozoites of E. histolytica with porcine colonic fragments and observed a disruption of the mucosal architecture. Then, we showed that outbred pigs can be used to reproduce some lesions associated with human amebiasis. A detailed analysis was performed using a washed closed-jejunal loops model. In loops inoculated with virulent amebas a severe acute ulcerative jejunitis was observed with large hemorrhagic lesions 14 days post-inoculation associated with the presence of the trophozoites in the depth of the mucosa in two out four animals. Furthermore, typical large sized hepatic abscesses were observed in the liver of one animal 7 days post-injection in the portal vein and the liver parenchyma. CONCLUSIONS: The pig model could help with simultaneously studying intestinal and extraintestinal lesion development.

  1. New ICRP human respiratory tract model

    International Nuclear Information System (INIS)

    Bailey, M.R.

    1993-01-01

    The new ICRP dosimetric model for the human respiratory tract is based on the premise that the large differences in radiation sensitivity of respiratory tract tissues, and the wide range of doses they receive argue for calculating specific tissue doses rather than average lung doses. The model is also directly applicable to the worldwide population of both workers and the public. The requirement to describe intake, and deposition, clearance and dosimetry in each respiratory tract region, for a wide range of subjects at various levels of exercise necessarily means that the model is more complex than that of ICRP Publication 30. The widespread use of powerful personal computers, and the availability of user-friendly software to implement the model, however, will make it widely and readily accessible when the report is published. (Author)

  2. Biomedical Simulation Models of Human Auditory Processes

    Science.gov (United States)

    Bicak, Mehmet M. A.

    2012-01-01

    Detailed acoustic engineering models that explore noise propagation mechanisms associated with noise attenuation and transmission paths created when using hearing protectors such as earplugs and headsets in high noise environments. Biomedical finite element (FE) models are developed based on volume Computed Tomography scan data which provides explicit external ear, ear canal, middle ear ossicular bones and cochlea geometry. Results from these studies have enabled a greater understanding of hearing protector to flesh dynamics as well as prioritizing noise propagation mechanisms. Prioritization of noise mechanisms can form an essential framework for exploration of new design principles and methods in both earplug and earcup applications. These models are currently being used in development of a novel hearing protection evaluation system that can provide experimentally correlated psychoacoustic noise attenuation. Moreover, these FE models can be used to simulate the effects of blast related impulse noise on human auditory mechanisms and brain tissue.

  3. Optimization of experimental human leukemia models (review

    Directory of Open Access Journals (Sweden)

    D. D. Pankov

    2012-01-01

    Full Text Available Actual problem of assessing immunotherapy prospects including antigenpecific cell therapy using animal models was covered in this review.Describe the various groups of currently existing animal models and methods of their creating – from different immunodeficient mice to severalvariants of tumor cells engraftment in them. The review addresses the possibility of tumor stem cells studying using mouse models for the leukemia treatment with adoptive cell therapy including WT1. Also issues of human leukemia cells migration and proliferation in a mice withdifferent immunodeficiency degree are discussed. To assess the potential immunotherapy efficacy comparison of immunodeficient mouse model with clinical situation in oncology patients after chemotherapy is proposed.

  4. Mimicking the Kidney: A Key Role in Organ-on-Chip Development

    Directory of Open Access Journals (Sweden)

    Roberto Paoli

    2016-07-01

    Full Text Available Pharmaceutical drug screening and research into diseases call for significant improvement in the effectiveness of current in vitro models. Better models would reduce the likelihood of costly failures at later drug development stages, while limiting or possibly even avoiding the use of animal models. In this regard, promising advances have recently been made by the so-called “organ-on-chip” (OOC technology. By combining cell culture with microfluidics, biomedical researchers have started to develop microengineered models of the functional units of human organs. With the capacity to mimic physiological microenvironments and vascular perfusion, OOC devices allow the reproduction of tissue- and organ-level functions. When considering drug testing, nephrotoxicity is a major cause of attrition during pre-clinical, clinical, and post-approval stages. Renal toxicity accounts for 19% of total dropouts during phase III drug evaluation—more than half the drugs abandoned because of safety concerns. Mimicking the functional unit of the kidney, namely the nephron, is therefore a crucial objective. Here we provide an extensive review of the studies focused on the development of a nephron-on-chip device.

  5. Correlation between model observer and human observer performance in CT imaging when lesion location is uncertain

    Energy Technology Data Exchange (ETDEWEB)

    Leng, Shuai; Yu, Lifeng; Zhang, Yi; McCollough, Cynthia H. [Department of Radiology, Mayo Clinic, 200 First Street Southwest, Rochester, Minnesota 55905 (United States); Carter, Rickey [Department of Biostatistics, Mayo Clinic, 200 First Street Southwest, Rochester, Minnesota 55905 (United States); Toledano, Alicia Y. [Biostatistics Consulting, LLC, 10606 Wheatley Street, Kensington, Maryland 20895 (United States)

    2013-08-15

    Purpose: The purpose of this study was to investigate the correlation between model observer and human observer performance in CT imaging for the task of lesion detection and localization when the lesion location is uncertain.Methods: Two cylindrical rods (3-mm and 5-mm diameters) were placed in a 35 × 26 cm torso-shaped water phantom to simulate lesions with −15 HU contrast at 120 kV. The phantom was scanned 100 times on a 128-slice CT scanner at each of four dose levels (CTDIvol = 5.7, 11.4, 17.1, and 22.8 mGy). Regions of interest (ROIs) around each lesion were extracted to generate images with signal-present, with each ROI containing 128 × 128 pixels. Corresponding ROIs of signal-absent images were generated from images without lesion mimicking rods. The location of the lesion (rod) in each ROI was randomly distributed by moving the ROIs around each lesion. Human observer studies were performed by having three trained observers identify the presence or absence of lesions, indicating the lesion location in each image and scoring confidence for the detection task on a 6-point scale. The same image data were analyzed using a channelized Hotelling model observer (CHO) with Gabor channels. Internal noise was added to the decision variables for the model observer study. Area under the curve (AUC) of ROC and localization ROC (LROC) curves were calculated using a nonparametric approach. The Spearman's rank order correlation between the average performance of the human observers and the model observer performance was calculated for the AUC of both ROC and LROC curves for both the 3- and 5-mm diameter lesions.Results: In both ROC and LROC analyses, AUC values for the model observer agreed well with the average values across the three human observers. The Spearman's rank order correlation values for both ROC and LROC analyses for both the 3- and 5-mm diameter lesions were all 1.0, indicating perfect rank ordering agreement of the figures of merit (AUC

  6. Effects of human hair on trans-cranial focused ultrasound efficacy in an ex-vivo cadaver model

    Science.gov (United States)

    Hananel, Arik; Snell, John W.; Kassell, Neal F.; Eames, Matthew D. C.

    2012-11-01

    Current practice before a trans-cranial MR guided Focused ultrasound procedure is shaving the patient head on treatment day. Here we present an initial attempt to evaluate the feasibility of trans-cranial FUS, in an unshaved, ex-vivo cadaver skull. We have sonicated using 220kHz and 710kHz head transducers, a cadaver skull filled with tissue mimicking phantom and covered with a wig made of human hair to evaluate feasibility of acoustic energy transfer in a full size model. Heating at focal point was measured using MR proton resonance shift thermometry. Results showed negligible effect of hair in 220kHz, and an 18% drop in temperature elevation when using 710kHz.

  7. Human embryonic stem cell lines model experimental human cytomegalovirus latency.

    Science.gov (United States)

    Penkert, Rhiannon R; Kalejta, Robert F

    2013-05-28

    Herpesviruses are highly successful pathogens that persist for the lifetime of their hosts primarily because of their ability to establish and maintain latent infections from which the virus is capable of productively reactivating. Human cytomegalovirus (HCMV), a betaherpesvirus, establishes latency in CD34(+) hematopoietic progenitor cells during natural infections in the body. Experimental infection of CD34(+) cells ex vivo has demonstrated that expression of the viral gene products that drive productive infection is silenced by an intrinsic immune defense mediated by Daxx and histone deacetylases through heterochromatinization of the viral genome during the establishment of latency. Additional mechanistic details about the establishment, let alone maintenance and reactivation, of HCMV latency remain scarce. This is partly due to the technical challenges of CD34(+) cell culture, most notably, the difficulty in preventing spontaneous differentiation that drives reactivation and renders them permissive for productive infection. Here we demonstrate that HCMV can establish, maintain, and reactivate in vitro from experimental latency in cultures of human embryonic stem cells (ESCs), for which spurious differentiation can be prevented or controlled. Furthermore, we show that known molecular aspects of HCMV latency are faithfully recapitulated in these cells. In total, we present ESCs as a novel, tractable model for studies of HCMV latency.

  8. Hypertrophic Nonunion Humerus Mimicking an Enchondroma

    Directory of Open Access Journals (Sweden)

    N. K. Magu

    2014-01-01

    Full Text Available Introduction. Although fractures of humeral shaft show excellent results with conservative management, nonunion does occur. Case Report. We bring forth the case of a young male with a 1.5-year-old hypertrophic nonunion of the humerus mimicking an enchondroma. The initial X-ray images of the patient appeared to be an enchondroma, which only on further evaluation and histopathological analysis was diagnosed conclusively to be a hypertrophic nonunion. Discussion. Enchondromas are often incidentally diagnosed benign tumours. It is however not common to misdiagnose a hypertrophic nonunion to be an enchondroma. We present this case to highlight the unique diagnostic dilemma the treating team had to face.

  9. Giant Spermatocele Mimicking Hydrocele: A Case Report

    Directory of Open Access Journals (Sweden)

    Hsin-Chih Yeh

    2007-07-01

    Full Text Available Spermatoceles are usually asymptomatic and often found incidentally during physical examination. We report a case of giant spermatocele that mimicked a hydrocele. A 55-year-old man suffered from right scrotal enlargement for several years. As the heavy sensation and scrotal soreness worsened in recent months, he came to our outpatient clinic for help. Hydrocele was suspected due to transilluminating appearance of the scrotal content. Surgical exploration was arranged and a giant spermatocele was found. Total excision of the spermatocele was performed and the patient recovered well. The specimen was sent for pathology and spermatocele with spermatozoa was noted.

  10. Nephrogenic rests mimicking Wilms' tumor on CT

    International Nuclear Information System (INIS)

    Subhas, Naveen; Siegelman, Stanley S.; Argani, Pedram; Gearhart, John P.

    2004-01-01

    Nephrogenic rests (NR) are persistent benign remnants of embryonic renal tissue. A small percentage of these may develop into Wilms' tumor (WT). Radiologic imaging is relied upon to differentiate between these entities, with the hallmark of malignant transformation being growth on serial imaging studies. There is, however, considerable overlap in their imaging characteristics. The authors present a case of two biopsy-proven NR in a 2-year-old girl with sporadic aniridia that were indistinguishable from WT on initial radiologic studies. One of the NR grew on serial imaging studies mimicking a WT, but after resection was confirmed to be a benign hyperplastic NR on pathologic examination. (orig.)

  11. Central skeletal sarcoidosis mimicking metastatic disease

    International Nuclear Information System (INIS)

    Talmi, Danit; Smith, Stacy; Mulligan, Michael E.

    2008-01-01

    Sarcoidosis is a systemic disease that histologically typically shows non-caseating granulomas. The most common radiologic finding is hilar and mediastinal adenopathy. Patients with widely disseminated disease may show involvement of the peripheral appendicular skeleton in 1-13% of such cases. A primary skeletal presentation without other manifestations typical of the disease is rare. We present a case of sarcoidosis in a middle-aged Caucasian man in whom the disease presented with widespread lytic lesions in the axial skeleton and long bones, mimicking metastatic disease. There was no involvement of the peripheral skeleton, skin or lungs. (orig.)

  12. Cogan's syndrome mimicking acute Lyme arthritis.

    Science.gov (United States)

    Schwegmann, J P; Enzenauer, R J

    1995-05-01

    A pediatric case of Cogan's syndrome mimicking acute Lyme arthritis is described. A 12-year-old black boy was admitted to the pediatric service for presumed right knee septic arthritis. Symptoms included acute pain and swelling with decreased range-of-motion. Although the patient's right knee symptoms and positive Lyme serology were consistent with a diagnosis of Lyme arthritis, the presence of sensorineural hearing loss and interstitial keratitis with inflammatory arthritis suggested a diagnosis of Cogan's syndrome. Subsequent Western blot analysis was negative for Borrelia burgdorferi antigens. The patient had dramatic clinical improvement of musculoskeletal and ophthalmologic complaints shortly after receiving high-dose corticosteroids, although residual sensorineural hearing loss persisted.

  13. Remote Cutaneous Breast Carcinoma Metastasis Mimicking Dermatitis

    Directory of Open Access Journals (Sweden)

    Annakan V Navaratnam

    2015-01-01

    Full Text Available Cutaneous metastases from primary internal malignancies are an uncommon presentation. Cutaneous metastases are more frequently seen in breast cancer than in any other visceral malignancy in women. Medical practitioners should be vigilant of the possibility of unusual presentations of metastatic disease in breast cancer patients with lobular carcinoma presenting as cutaneous lesions mimicking benign dermatological conditions. Herein, we present a case of a 75-year-old woman presenting with cutaneous lobular breast carcinoma metastases on her anterior right leg, which had previously been misdiagnosed as dermatitis for 9 years.

  14. Unusual presentation of chondroblastoma mimicking Trevor's disease

    Directory of Open Access Journals (Sweden)

    Y Karkhur

    2017-01-01

    Full Text Available Chondroblastoma is a benign bone tumor, represents 1%–2% of all primary bone tumors, typically seen in patients 10–25-year-old and more common in males. It occurs most frequently in the distal femur, proximal tibia, and proximal humerus. Soft tissue extension is extremely rare. Adjacent joints may develop effusions, but the tumor mass protruding into the joint has never been seen in case of chondroblastoma. We report a rare case of intra-articular chondroblastoma arising from proximal tibia in a 16-year-old boy and growing into the knee joint mimicking an intra-articular osteochondroma.

  15. Floating retained root lesion mimicking apical periodontitis.

    Science.gov (United States)

    Chung, Ming-Pang; Chen, Chih-Ping; Shieh, Yi-Shing

    2009-10-01

    A case of a retained root tip simulating apical periodontitis on radiographic examination is described. The retained root tip, originating from the left lower first molar, floated under the left lower second premolar apical region mimicking apical periodontitis. It appeared as an ill-defined periapical radiolucency containing a smaller radiodense mass on radiograph. The differential diagnosis included focal sclerosing osteomyelitis (condensing osteitis) and ossifying fibroma. Upon exicisional biopsy, a retained root associated with granulation tissue was found. After 1-year follow-up, the patient was asymptomatic and the periradicular lesion was healing. Meanwhile, the associated tooth showed a normal response to stimulation testing.

  16. A Mouse Model for Human Anal Cancer

    Science.gov (United States)

    Stelzer, Marie K.; Pitot, Henry C.; Liem, Amy; Schweizer, Johannes; Mahoney, Charles; Lambert, Paul F.

    2010-01-01

    Human anal cancers are associated with high-risk human papillomaviruses (HPVs) that cause other anogenital cancers and head and neck cancers. As with other cancers, HPV16 is the most common high-risk HPV in anal cancers. We describe the generation and characterization of a mouse model for human anal cancer. This model makes use of K14E6 and K14E7 transgenic mice in which the HPV16 E6 and E7 genes are directed in their expression to stratified squamous epithelia. HPV16 E6 and E7 possess oncogenic properties including but not limited to their capacity to inactivate the cellular tumor suppressors p53 and pRb, respectively. Both E6 and E7 were found to be functionally expressed in the anal epithelia of K14E6/K14E7 transgenic mice. To assess the susceptibility of these mice to anal cancer, mice were treated topically with dimethylbenz[a]anthracene (DMBA), a chemical carcinogen that is known to induce squamous cell carcinomas in other sites. Nearly 50% of DMBA-treated HPV16 E6/E7 transgenic mice showed overt signs of tumors; whereas, none of the like treated non-transgenic mice showed tumors. Histopathological analyses confirmed that the HPV16 transgenic mice were increased in their susceptibility to anal cancers and precancerous lesions. Biomarker analyses demonstrated that these mouse anal cancers exhibit properties that are similar to those observed in HPV-positive precursors to human anal cancer. This is the first mouse model for investigating the contributions of viral and cellular factors in anal carcinogenesis, and should provide a platform for assessing new therapeutic modalities for treating and/or preventing this type of cancer. PMID:20947489

  17. Human reliability data collection and modelling

    International Nuclear Information System (INIS)

    1991-09-01

    The main purpose of this document is to review and outline the current state-of-the-art of the Human Reliability Assessment (HRA) used for quantitative assessment of nuclear power plants safe and economical operation. Another objective is to consider Human Performance Indicators (HPI) which can alert plant manager and regulator to departures from states of normal and acceptable operation. These two objectives are met in the three sections of this report. The first objective has been divided into two areas, based on the location of the human actions being considered. That is, the modelling and data collection associated with control room actions are addressed first in chapter 1 while actions outside the control room (including maintenance) are addressed in chapter 2. Both chapters 1 and 2 present a brief outline of the current status of HRA for these areas, and major outstanding issues. Chapter 3 discusses HPI. Such performance indicators can signal, at various levels, changes in factors which influence human performance. The final section of this report consists of papers presented by the participants of the Technical Committee Meeting. A separate abstract was prepared for each of these papers. Refs, figs and tabs

  18. Modeling human reliability analysis using MIDAS

    International Nuclear Information System (INIS)

    Boring, R. L.

    2006-01-01

    This paper documents current efforts to infuse human reliability analysis (HRA) into human performance simulation. The Idaho National Laboratory is teamed with NASA Ames Research Center to bridge the SPAR-H HRA method with NASA's Man-machine Integration Design and Analysis System (MIDAS) for use in simulating and modeling the human contribution to risk in nuclear power plant control room operations. It is anticipated that the union of MIDAS and SPAR-H will pave the path for cost-effective, timely, and valid simulated control room operators for studying current and next generation control room configurations. This paper highlights considerations for creating the dynamic HRA framework necessary for simulation, including event dependency and granularity. This paper also highlights how the SPAR-H performance shaping factors can be modeled in MIDAS across static, dynamic, and initiator conditions common to control room scenarios. This paper concludes with a discussion of the relationship of the workload factors currently in MIDAS and the performance shaping factors in SPAR-H. (authors)

  19. The Five Key Questions of Human Performance Modeling.

    Science.gov (United States)

    Wu, Changxu

    2018-01-01

    Via building computational (typically mathematical and computer simulation) models, human performance modeling (HPM) quantifies, predicts, and maximizes human performance, human-machine system productivity and safety. This paper describes and summarizes the five key questions of human performance modeling: 1) Why we build models of human performance; 2) What the expectations of a good human performance model are; 3) What the procedures and requirements in building and verifying a human performance model are; 4) How we integrate a human performance model with system design; and 5) What the possible future directions of human performance modeling research are. Recent and classic HPM findings are addressed in the five questions to provide new thinking in HPM's motivations, expectations, procedures, system integration and future directions.

  20. Human Walk Modeled by PCPG to Control a Lower Limb Neuroprosthesis by High-Level Commands

    Directory of Open Access Journals (Sweden)

    Matthieu Duvinage

    2012-06-01

    Full Text Available Current active leg prostheses do not integrate the most recent advances in Brain-Computer Interfaces (BCI and bipedal robotics. Moreover, their actuators are seldom driven by the subject’s intention. This paper aims at showing a summary of our current results in the field of human gait rehabilitation. In a first prototype, the main focus was on people suffering from foot drop problems, i.e. people who are unable to lift their feet. However, current work is focusing on a full active ankle orthosis. The approach is threefold: a BCI system, a gait model and an orthosis. Thanks to the BCI system, patients are able to generate high-level commands. Typically, a command could represent a speed modification. Then, a gait model based on a programmable central pattern generator is used to generate the adequate kinematics. Finally, the orthosis is tracking this kinematics when the foot is in the air, whereas, the orthosis is mimicking a spring when the foot is on the ground.

  1. The quantitative modelling of human spatial habitability

    Science.gov (United States)

    Wise, J. A.

    1985-01-01

    A model for the quantitative assessment of human spatial habitability is presented in the space station context. The visual aspect assesses how interior spaces appear to the inhabitants. This aspect concerns criteria such as sensed spaciousness and the affective (emotional) connotations of settings' appearances. The kinesthetic aspect evaluates the available space in terms of its suitability to accommodate human movement patterns, as well as the postural and anthrometric changes due to microgravity. Finally, social logic concerns how the volume and geometry of available space either affirms or contravenes established social and organizational expectations for spatial arrangements. Here, the criteria include privacy, status, social power, and proxemics (the uses of space as a medium of social communication).

  2. Mimicking Seawater For Culturing Marine Bacteria

    DEFF Research Database (Denmark)

    Rygaard, Anita Mac; Sonnenschein, Eva; Gram, Lone

    2015-01-01

    Only about 1% of marine bacteria have been brought into culture using traditional techniques. The purpose of this study was to investigate if mimicking the natural bacterial environment can increase culturability.We used marine substrates containing defined algal polymers or gellan gum as solidif......Only about 1% of marine bacteria have been brought into culture using traditional techniques. The purpose of this study was to investigate if mimicking the natural bacterial environment can increase culturability.We used marine substrates containing defined algal polymers or gellan gum...... as solidifying agents, and enumerated bacteria from seawater and algal exudates. We tested if culturability could be influenced by addition of quorum sensing signals (AHLs). All plates were incubated at 15°C. Bacterial counts (CFU/g) from algal exudates from brown algae were highest on media containing algal...... polymers. In general, bacteria isolated from algal exudates preferred more rich media than bacteria isolated from seawater. Overall, culturability ranged from 0.01 to 0.8% as compared to total cell count. Substitution of agar with gellan gum increased the culturability of seawater bacteria approximately...

  3. Imaging findings of mimickers of hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Tae Kyoung Kim

    2015-12-01

    Full Text Available Radiological imaging plays a crucial role in the diagnosis of hepatocellular carcinoma (HCC as the noninvasive diagnosis of HCC in high-risk patients by typical imaging findings alone is widely adopted in major practice guidelines for HCC. While imaging techniques have markedly improved in detecting small liver lesions, they often detect incidental benign liver lesions and non-hepatocellular malignancy that can be misdiagnosed as HCC. The most common mimicker of HCC in cirrhotic liver is nontumorous arterioportal shunts that are seen as focal hypervascular liver lesions on dynamic contrast-enhanced cross-sectional imaging. Rapidly enhancing hemangiomas can be easily misdiagnosed as HCC especially on MR imaging with liver-specific contrast agent. Focal inflammatory liver lesions mimic HCC by demonstrating arterial-phase hypervascularity and subsequent washout on dynamic contrast-enhanced imaging. It is important to recognize the suggestive imaging findings for intrahepatic cholangiocarcinoma (CC as the management of CC is largely different from that of HCC. There are other benign mimickers of HCC such as angiomyolipomas and focal nodular hyperplasia-like nodules. Recognition of their typical imaging findings can reduce false-positive HCC diagnosis.

  4. Clinical and Histologic Mimickers of Celiac Disease.

    Science.gov (United States)

    Kamboj, Amrit K; Oxentenko, Amy S

    2017-08-17

    Celiac disease is an autoimmune disorder of the small bowel, classically associated with diarrhea, abdominal pain, and malabsorption. The diagnosis of celiac disease is made when there are compatible clinical features, supportive serologic markers, representative histology from the small bowel, and response to a gluten-free diet. Histologic findings associated with celiac disease include intraepithelial lymphocytosis, crypt hyperplasia, villous atrophy, and a chronic inflammatory cell infiltrate in the lamina propria. It is important to recognize and diagnose celiac disease, as strict adherence to a gluten-free diet can lead to resolution of clinical and histologic manifestations of the disease. However, many other entities can present with clinical and/or histologic features of celiac disease. In this review article, we highlight key clinical and histologic mimickers of celiac disease. The evaluation of a patient with serologically negative enteropathy necessitates a carefully elicited history and detailed review by a pathologist. Medications can mimic celiac disease and should be considered in all patients with a serologically negative enteropathy. Many mimickers of celiac disease have clues to the underlying diagnosis, and many have a targeted therapy. It is necessary to provide patients with a correct diagnosis rather than subject them to a lifetime of an unnecessary gluten-free diet.

  5. Deformed Skull Morphology Is Caused by the Combined Effects of the Maldevelopment of Calvarias, Cranial Base and Brain in FGFR2-P253R Mice Mimicking Human Apert Syndrome.

    Science.gov (United States)

    Luo, Fengtao; Xie, Yangli; Xu, Wei; Huang, Junlan; Zhou, Siru; Wang, Zuqiang; Luo, Xiaoqing; Liu, Mi; Chen, Lin; Du, Xiaolan

    2017-01-01

    Apert syndrome (AS) is a common genetic syndrome in humans characterized with craniosynostosis. Apert patients and mouse models showed abnormalities in sutures, cranial base and brain, that may all be involved in the pathogenesis of skull malformation of Apert syndrome. To distinguish the differential roles of these components of head in the pathogenesis of the abnormal skull morphology of AS, we generated mouse strains specifically expressing mutant FGFR2 in chondrocytes, osteoblasts, and progenitor cells of central nervous system (CNS) by crossing Fgfr2 +/P253R-Neo mice with Col2a1-Cre, Osteocalcin-Cre (OC-Cre), and Nestin-Cre mice, respectively. We then quantitatively analyzed the skull and brain morphology of these mutant mice by micro-CT and micro-MRI using Euclidean distance matrix analysis (EDMA). Skulls of Col2a1-Fgfr2 +/P253R mice showed Apert syndrome-like dysmorphology, such as shortened skull dimensions along the rostrocaudal axis, shortened nasal bone, and evidently advanced ossification of cranial base synchondroses. The OC-Fgfr2 +/P253R mice showed malformation in face at 8-week stage. Nestin-Fgfr2 +/P253R mice exhibited increased dorsoventral height and rostrocaudal length on the caudal skull and brain at 8 weeks. Our study indicates that the abnormal skull morphology of AS is caused by the combined effects of the maldevelopment in calvarias, cranial base, and brain tissue. These findings further deepen our knowledge about the pathogenesis of the abnormal skull morphology of AS, and provide new clues for the further analyses of skull phenotypes and clinical management of AS.

  6. The quantitative modelling of human spatial habitability

    Science.gov (United States)

    Wise, James A.

    1988-01-01

    A theoretical model for evaluating human spatial habitability (HuSH) in the proposed U.S. Space Station is developed. Optimizing the fitness of the space station environment for human occupancy will help reduce environmental stress due to long-term isolation and confinement in its small habitable volume. The development of tools that operationalize the behavioral bases of spatial volume for visual kinesthetic, and social logic considerations is suggested. This report further calls for systematic scientific investigations of how much real and how much perceived volume people need in order to function normally and with minimal stress in space-based settings. The theoretical model presented in this report can be applied to any size or shape interior, at any scale of consideration, for the Space Station as a whole to an individual enclosure or work station. Using as a point of departure the Isovist model developed by Dr. Michael Benedikt of the U. of Texas, the report suggests that spatial habitability can become as amenable to careful assessment as engineering and life support concerns.

  7. Modelling human eye under blast loading.

    Science.gov (United States)

    Esposito, L; Clemente, C; Bonora, N; Rossi, T

    2015-01-01

    Primary blast injury (PBI) is the general term that refers to injuries resulting from the mere interaction of a blast wave with the body. Although few instances of primary ocular blast injury, without a concomitant secondary blast injury from debris, are documented, some experimental studies demonstrate its occurrence. In order to investigate PBI to the eye, a finite element model of the human eye using simple constitutive models was developed. The material parameters were calibrated by a multi-objective optimisation performed on available eye impact test data. The behaviour of the human eye and the dynamics of mechanisms occurring under PBI loading conditions were modelled. For the generation of the blast waves, different combinations of explosive (trinitrotoluene) mass charge and distance from the eye were analysed. An interpretation of the resulting pressure, based on the propagation and reflection of the waves inside the eye bulb and orbit, is proposed. The peculiar geometry of the bony orbit (similar to a frustum cone) can induce a resonance cavity effect and generate a pressure standing wave potentially hurtful for eye tissues.

  8. Short-term plasticity and long-term potentiation mimicked in single inorganic synapses

    Science.gov (United States)

    Ohno, Takeo; Hasegawa, Tsuyoshi; Tsuruoka, Tohru; Terabe, Kazuya; Gimzewski, James K.; Aono, Masakazu

    2011-08-01

    Memory is believed to occur in the human brain as a result of two types of synaptic plasticity: short-term plasticity (STP) and long-term potentiation (LTP; refs , , , ). In neuromorphic engineering, emulation of known neural behaviour has proven to be difficult to implement in software because of the highly complex interconnected nature of thought processes. Here we report the discovery of a Ag2S inorganic synapse, which emulates the synaptic functions of both STP and LTP characteristics through the use of input pulse repetition time. The structure known as an atomic switch, operating at critical voltages, stores information as STP with a spontaneous decay of conductance level in response to intermittent input stimuli, whereas frequent stimulation results in a transition to LTP. The Ag2S inorganic synapse has interesting characteristics with analogies to an individual biological synapse, and achieves dynamic memorization in a single device without the need of external preprogramming. A psychological model related to the process of memorizing and forgetting is also demonstrated using the inorganic synapses. Our Ag2S element indicates a breakthrough in mimicking synaptic behaviour essential for the further creation of artificial neural systems that emulate characteristics of human memory.

  9. Modeling human comprehension of data visualizations

    Energy Technology Data Exchange (ETDEWEB)

    Matzen, Laura E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Haass, Michael Joseph [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Divis, Kristin Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wilson, Andrew T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    This project was inspired by two needs. The first is a need for tools to help scientists and engineers to design effective data visualizations for communicating information, whether to the user of a system, an analyst who must make decisions based on complex data, or in the context of a technical report or publication. Most scientists and engineers are not trained in visualization design, and they could benefit from simple metrics to assess how well their visualization's design conveys the intended message. In other words, will the most important information draw the viewer's attention? The second is the need for cognition-based metrics for evaluating new types of visualizations created by researchers in the information visualization and visual analytics communities. Evaluating visualizations is difficult even for experts. However, all visualization methods and techniques are intended to exploit the properties of the human visual system to convey information efficiently to a viewer. Thus, developing evaluation methods that are rooted in the scientific knowledge of the human visual system could be a useful approach. In this project, we conducted fundamental research on how humans make sense of abstract data visualizations, and how this process is influenced by their goals and prior experience. We then used that research to develop a new model, the Data Visualization Saliency Model, that can make accurate predictions about which features in an abstract visualization will draw a viewer's attention. The model is an evaluation tool that can address both of the needs described above, supporting both visualization research and Sandia mission needs.

  10. Pyramid algorithms as models of human cognition

    Science.gov (United States)

    Pizlo, Zygmunt; Li, Zheng

    2003-06-01

    There is growing body of experimental evidence showing that human perception and cognition involves mechanisms that can be adequately modeled by pyramid algorithms. The main aspect of those mechanisms is hierarchical clustering of information: visual images, spatial relations, and states as well as transformations of a problem. In this paper we review prior psychophysical and simulation results on visual size transformation, size discrimination, speed-accuracy tradeoff, figure-ground segregation, and the traveling salesman problem. We also present our new results on graph search and on the 15-puzzle.

  11. Development and function of human innate immune cells in a humanized mouse model.

    Science.gov (United States)

    Rongvaux, Anthony; Willinger, Tim; Martinek, Jan; Strowig, Till; Gearty, Sofia V; Teichmann, Lino L; Saito, Yasuyuki; Marches, Florentina; Halene, Stephanie; Palucka, A Karolina; Manz, Markus G; Flavell, Richard A

    2014-04-01

    Mice repopulated with human hematopoietic cells are a powerful tool for the study of human hematopoiesis and immune function in vivo. However, existing humanized mouse models cannot support development of human innate immune cells, including myeloid cells and natural killer (NK) cells. Here we describe two mouse strains called MITRG and MISTRG, in which human versions of four genes encoding cytokines important for innate immune cell development are knocked into their respective mouse loci. The human cytokines support the development and function of monocytes, macrophages and NK cells derived from human fetal liver or adult CD34(+) progenitor cells injected into the mice. Human macrophages infiltrated a human tumor xenograft in MITRG and MISTRG mice in a manner resembling that observed in tumors obtained from human patients. This humanized mouse model may be used to model the human immune system in scenarios of health and pathology, and may enable evaluation of therapeutic candidates in an in vivo setting relevant to human physiology.

  12. Tracking Human Immunodeficiency Virus-1 Infection in the Humanized DRAG Mouse Model

    OpenAIRE

    Jiae Kim; Jiae Kim; Kristina K. Peachman; Kristina K. Peachman; Ousman Jobe; Ousman Jobe; Elaine B. Morrison; Atef Allam; Atef Allam; Linda Jagodzinski; Sofia A. Casares; Mangala Rao

    2017-01-01

    Humanized mice are emerging as an alternative model system to well-established non-human primate (NHP) models for studying human immunodeficiency virus (HIV)-1 biology and pathogenesis. Although both NHP and humanized mice have their own strengths and could never truly reflect the complex human immune system and biology, there are several advantages of using the humanized mice in terms of using primary HIV-1 for infection instead of simian immunodeficiency virus or chimera simian/HIV. Several...

  13. Virtual pharmacokinetic model of human eye.

    Science.gov (United States)

    Kotha, Sreevani; Murtomäki, Lasse

    2014-07-01

    A virtual pharmacokinetic 3D model of the human eye is built using Comsol Multiphysics® software, which is based on the Finite Element Method (FEM). The model considers drug release from a polymer patch placed on sclera. The model concentrates on the posterior part of the eye, retina being the target tissue, and comprises the choroidal blood flow, partitioning of the drug between different tissues and active transport at the retina pigment epithelium (RPE)-choroid boundary. Although most straightforward, in order to check the mass balance, no protein binding or metabolism is yet included. It appeared that the most important issue in obtaining reliable simulation results is the finite element mesh, while time stepping has hardly any significance. Simulations were extended to 100,000 s. The concentration of a drug is shown as a function of time at various points of retina, as well as its average value, varying several parameters in the model. This work demonstrates how anybody with basic knowledge of calculus is able to build physically meaningful models of quite complex biological systems. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Human factors engineering program review model

    International Nuclear Information System (INIS)

    1994-07-01

    The staff of the Nuclear Regulatory Commission is performing nuclear power plant design certification reviews based on a design process plan that describes the human factors engineering (HFE) program elements that are necessary and sufficient to develop an acceptable detailed design specification and an acceptable implemented design. There are two principal reasons for this approach. First, the initial design certification applications submitted for staff review did not include detailed design information. Second, since human performance literature and industry experiences have shown that many significant human factors issues arise early in the design process, review of the design process activities and results is important to the evaluation of an overall design. However, current regulations and guidance documents do not address the criteria for design process review. Therefore, the HFE Program Review Model (HFE PRM) was developed as a basis for performing design certification reviews that include design process evaluations as well as review of the final design. A central tenet of the HFE PRM is that the HFE aspects of the plant should be developed, designed, and evaluated on the basis of a structured top-down system analysis using accepted HFE principles. The HFE PRM consists of ten component elements. Each element in divided into four sections: Background, Objective, Applicant Submittals, and Review Criteria. This report describes the development of the HFE PRM and gives a detailed description of each HFE review element

  15. A human neurodevelopmental model for Williams syndrome.

    Science.gov (United States)

    Chailangkarn, Thanathom; Trujillo, Cleber A; Freitas, Beatriz C; Hrvoj-Mihic, Branka; Herai, Roberto H; Yu, Diana X; Brown, Timothy T; Marchetto, Maria C; Bardy, Cedric; McHenry, Lauren; Stefanacci, Lisa; Järvinen, Anna; Searcy, Yvonne M; DeWitt, Michelle; Wong, Wenny; Lai, Philip; Ard, M Colin; Hanson, Kari L; Romero, Sarah; Jacobs, Bob; Dale, Anders M; Dai, Li; Korenberg, Julie R; Gage, Fred H; Bellugi, Ursula; Halgren, Eric; Semendeferi, Katerina; Muotri, Alysson R

    2016-08-18

    Williams syndrome is a genetic neurodevelopmental disorder characterized by an uncommon hypersociability and a mosaic of retained and compromised linguistic and cognitive abilities. Nearly all clinically diagnosed individuals with Williams syndrome lack precisely the same set of genes, with breakpoints in chromosome band 7q11.23 (refs 1-5). The contribution of specific genes to the neuroanatomical and functional alterations, leading to behavioural pathologies in humans, remains largely unexplored. Here we investigate neural progenitor cells and cortical neurons derived from Williams syndrome and typically developing induced pluripotent stem cells. Neural progenitor cells in Williams syndrome have an increased doubling time and apoptosis compared with typically developing neural progenitor cells. Using an individual with atypical Williams syndrome, we narrowed this cellular phenotype to a single gene candidate, frizzled 9 (FZD9). At the neuronal stage, layer V/VI cortical neurons derived from Williams syndrome were characterized by longer total dendrites, increased numbers of spines and synapses, aberrant calcium oscillation and altered network connectivity. Morphometric alterations observed in neurons from Williams syndrome were validated after Golgi staining of post-mortem layer V/VI cortical neurons. This model of human induced pluripotent stem cells fills the current knowledge gap in the cellular biology of Williams syndrome and could lead to further insights into the molecular mechanism underlying the disorder and the human social brain.

  16. Behavior genetic modeling of human fertility

    DEFF Research Database (Denmark)

    Rodgers, J L; Kohler, H P; Kyvik, K O

    2001-01-01

    Behavior genetic designs and analysis can be used to address issues of central importance to demography. We use this methodology to document genetic influence on human fertility. Our data come from Danish twin pairs born from 1953 to 1959, measured on age at first attempt to get pregnant (First......Try) and number of children (NumCh). Behavior genetic models were fitted using structural equation modeling and DF analysis. A consistent medium-level additive genetic influence was found for NumCh, equal across genders; a stronger genetic influence was identified for FirstTry, greater for females than for males....... A bivariate analysis indicated significant shared genetic variance between NumCh and FirstTry....

  17. A comparison of scaffold-free and scaffold-based reconstructed human skin models as alternatives to animal use.

    Science.gov (United States)

    Kinikoglu, Beste

    2017-12-01

    Tissue engineered full-thickness human skin substitutes have various applications in the clinic and in the laboratory, such as in the treatment of burns or deep skin defects, and as reconstructed human skin models in the safety testing of drugs and cosmetics and in the fundamental study of skin biology and pathology. So far, different approaches have been proposed for the generation of reconstructed skin, each with its own advantages and disadvantages. Here, the classic tissue engineering approach, based on cell-seeded polymeric scaffolds, is compared with the less-studied cell self-assembly approach, where the cells are coaxed to synthesise their own extracellular matrix (ECM). The resulting full-thickness human skin substitutes were analysed by means of histological and immunohistochemical analyses. It was found that both the scaffold-free and the scaffold-based skin equivalents successfully mimicked the functionality and morphology of native skin, with complete epidermal differentiation (as determined by the expression of filaggrin), the presence of a continuous basement membrane expressing collagen VII, and new ECM deposition by dermal fibroblasts. On the other hand, the scaffold-free model had a thicker epidermis and a significantly higher number of Ki67-positive proliferative cells, indicating a higher capacity for self-renewal, as compared to the scaffold-based model. 2017 FRAME.

  18. Human Guidance Behavior Decomposition and Modeling

    Science.gov (United States)

    Feit, Andrew James

    Trained humans are capable of high performance, adaptable, and robust first-person dynamic motion guidance behavior. This behavior is exhibited in a wide variety of activities such as driving, piloting aircraft, skiing, biking, and many others. Human performance in such activities far exceeds the current capability of autonomous systems in terms of adaptability to new tasks, real-time motion planning, robustness, and trading safety for performance. The present work investigates the structure of human dynamic motion guidance that enables these performance qualities. This work uses a first-person experimental framework that presents a driving task to the subject, measuring control inputs, vehicle motion, and operator visual gaze movement. The resulting data is decomposed into subspace segment clusters that form primitive elements of action-perception interactive behavior. Subspace clusters are defined by both agent-environment system dynamic constraints and operator control strategies. A key contribution of this work is to define transitions between subspace cluster segments, or subgoals, as points where the set of active constraints, either system or operator defined, changes. This definition provides necessary conditions to determine transition points for a given task-environment scenario that allow a solution trajectory to be planned from known behavior elements. In addition, human gaze behavior during this task contains predictive behavior elements, indicating that the identified control modes are internally modeled. Based on these ideas, a generative, autonomous guidance framework is introduced that efficiently generates optimal dynamic motion behavior in new tasks. The new subgoal planning algorithm is shown to generate solutions to certain tasks more quickly than existing approaches currently used in robotics.

  19. A modular approach to numerical human body modeling

    NARCIS (Netherlands)

    Forbes, P.A.; Griotto, G.; Rooij, L. van

    2007-01-01

    The choice of a human body model for a simulated automotive impact scenario must take into account both accurate model response and computational efficiency as key factors. This study presents a "modular numerical human body modeling" approach which allows the creation of a customized human body

  20. Feasibility Study on a Microwave-Based Sensor for Measuring Hydration Level Using Human Skin Models.

    Science.gov (United States)

    Brendtke, Rico; Wiehl, Michael; Groeber, Florian; Schwarz, Thomas; Walles, Heike; Hansmann, Jan

    2016-01-01

    Tissue dehydration results in three major types of exsiccosis--hyper-, hypo-, or isonatraemia. All three types entail alterations of salt concentrations leading to impaired biochemical processes, and can finally cause severe morbidity. The aim of our study was to demonstrate the feasibility of a microwave-based sensor technology for the non-invasive measurement of the hydration status. Electromagnetic waves at high frequencies interact with molecules, especially water. Hence, if a sample contains free water molecules, this can be detected in a reflected microwave signal. To develop the sensor system, human three-dimensional skin equivalents were instituted as a standardized test platform mimicking reproducible exsiccosis scenarios. Therefore, skin equivalents with a specific hydration and density of matrix components were generated and microwave measurements were performed. Hydration-specific spectra allowed deriving the hydration state of the skin models. A further advantage of the skin equivalents was the characterization of the impact of distinct skin components on the measured signals to investigate mechanisms of signal generation. The results demonstrate the feasibility of a non-invasive microwave-based hydration sensor technology. The sensor bears potential to be integrated in a wearable medical device for personal health monitoring.

  1. Feasibility Study on a Microwave-Based Sensor for Measuring Hydration Level Using Human Skin Models.

    Directory of Open Access Journals (Sweden)

    Rico Brendtke

    Full Text Available Tissue dehydration results in three major types of exsiccosis--hyper-, hypo-, or isonatraemia. All three types entail alterations of salt concentrations leading to impaired biochemical processes, and can finally cause severe morbidity. The aim of our study was to demonstrate the feasibility of a microwave-based sensor technology for the non-invasive measurement of the hydration status. Electromagnetic waves at high frequencies interact with molecules, especially water. Hence, if a sample contains free water molecules, this can be detected in a reflected microwave signal. To develop the sensor system, human three-dimensional skin equivalents were instituted as a standardized test platform mimicking reproducible exsiccosis scenarios. Therefore, skin equivalents with a specific hydration and density of matrix components were generated and microwave measurements were performed. Hydration-specific spectra allowed deriving the hydration state of the skin models. A further advantage of the skin equivalents was the characterization of the impact of distinct skin components on the measured signals to investigate mechanisms of signal generation. The results demonstrate the feasibility of a non-invasive microwave-based hydration sensor technology. The sensor bears potential to be integrated in a wearable medical device for personal health monitoring.

  2. Acute perimyocarditis mimicking transmural myocardial infarction

    Directory of Open Access Journals (Sweden)

    Omar Hesham R

    2009-12-01

    Full Text Available Abstract Although acute pericarditis has charachteristic electrocardiographic (ECG findings that differentiate it from acute ST segment elevation myocardial infarction (MI; in certain cases diagnosis is somewhat difficult especially when the ECG reveals focal instead of diffuse changes and moreover when pericarditis is associated with an underlying myocarditis causing elevation of the cardiac biomarkers therefore increasing the difficulty in differentiating between both enteties. This is especially important because adverse lethal side effect can occur if thrombolytic therapy is administered for a patient with acute pericarditis, or if a diagnosis of transmural MI is missed. In this case report we are describing an 18 year old male patient who presented with an acute onset of severe chest pain associated with focal ECG changes and elevated cardiac enzymes mimicking transmural MI. This report aims to sensitize readers to this debate and create awareness among cardiologists and intensivists with both presentations and how to reach an accurate diagnosis.

  3. Contiguous spinal metastasis mimicking infectious spondylodiscitis

    International Nuclear Information System (INIS)

    Lee, Chul Min; Lee, Seung Hun; Bae, Ji Yoon

    2015-01-01

    Differential diagnosis between spinal metastasis and infectious spondylodiscitis is one of the occasional challenges in daily clinical practice. We encountered an unusual case of spinal metastasis in a 75-year-old female breast cancer patient that mimicked infectious spondylodiscitis. Magnetic resonance imaging (MRI) showed diffuse bone marrow infiltrations with paraspinal soft tissue infiltrative changes in 5 contiguous cervical vertebrae without significant compression fracture or cortical destruction. These MRI findings made it difficult to differentiate between spinal metastasis and infectious spondylodiscitis. Infectious spondylodiscitis such as tuberculous spondylodiscitis was regarded as the more appropriate diagnosis due to the continuous involvement of > 5 cervical vertebrae. The patient's clinical presentation also supported the presumptive diagnosis of infectious spondylodiscitis rather than spinal metastasis. Intravenous antibiotics were administered, but clinical symptoms worsened despite treatment. After pathologic confirmation by computed tomography-guided biopsy, we were able to confirm a final diagnosis of spinal metastasis

  4. Orbital roof encephalocele mimicking a destructive neoplasm.

    Science.gov (United States)

    Alsuhaibani, Adel H; Hitchon, Patrick W; Smoker, Wendy R K; Lee, Andrew G; Nerad, Jeffrey A

    2011-01-01

    The purpose of this case report is to report an orbital roof encephalocele mimicking a destructive orbital neoplasm. Orbital roof encephalocele is uncommon but can mimic neoplasm. One potential mechanism for the orbital roof destruction is a post-traumatic "growing orbital roof fracture." The growing fracture has been reported mostly in children but can occur in adults. Alternative potential etiologies for the encephalocele are discussed, including Gorham syndrome. Orbital roof encephalocele is uncommon in adults, and the findings can superficially resemble an orbital neoplasm. Radiographic and clinical features that might suggest the correct diagnosis include a prior history of trauma, overlying frontal lobe encephalomalacia without significant mass effect or edema, and an orbital roof defect. The "growing fracture" mechanism may be a potential explanation for the orbital roof destruction in some cases.

  5. [Primary central nervous system lymphoma mimicking ventriculitis].

    Science.gov (United States)

    Yamamoto, Shiro; Nagano, Seiji; Shibata, Sumiya; Kunieda, Takeharu; Imai, Yukihiro; Kohara, Nobuo

    2013-01-01

    A 66-year-old man presented with deteriorated bradykinesia, gait disturbance, disorientation, and urinary incontinence for three weeks. Magnetic resonance imaging (MRI) showed dilatation of the ventricles. Cerebrospinal fluid (CSF) examination demonstrated lymphocytic pleocytosis, elevation of protein levels, and decreased of glucose levels. A gadolinium-enhanced MRI revealed lesions in the ventricular wall and choroid plexus, mimicking ventriculitis. No evidence of bacterial, fungal, mycobacterial, or viral infections were observed in the CSF. Flow cytometry of CSF showed predominance of CD20+, λ+ cells. PCR examination of CSF revealed positive IgH gene rearrangement, suggesting B cell lymphoma. Endoscopic brain biopsy showed diffuse large B cell lymphoma. As the patient had no evidence of lymphoma in the other organs, we made a diagnosed of primary central nervous system lymphoma (PCNSL). A limited intraventricular spread of PCNSL is rare but important as one of differential diagnosis of ventriculitis.

  6. Contiguous spinal metastasis mimicking infectious spondylodiscitis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chul Min; Lee, Seung Hun [Dept. of Radiology, Hanyang University Hospital, Seoul (Korea, Republic of); Bae, Ji Yoon [Dept. of Pathology, National Police Hospital, Seoul (Korea, Republic of)

    2015-12-15

    Differential diagnosis between spinal metastasis and infectious spondylodiscitis is one of the occasional challenges in daily clinical practice. We encountered an unusual case of spinal metastasis in a 75-year-old female breast cancer patient that mimicked infectious spondylodiscitis. Magnetic resonance imaging (MRI) showed diffuse bone marrow infiltrations with paraspinal soft tissue infiltrative changes in 5 contiguous cervical vertebrae without significant compression fracture or cortical destruction. These MRI findings made it difficult to differentiate between spinal metastasis and infectious spondylodiscitis. Infectious spondylodiscitis such as tuberculous spondylodiscitis was regarded as the more appropriate diagnosis due to the continuous involvement of > 5 cervical vertebrae. The patient's clinical presentation also supported the presumptive diagnosis of infectious spondylodiscitis rather than spinal metastasis. Intravenous antibiotics were administered, but clinical symptoms worsened despite treatment. After pathologic confirmation by computed tomography-guided biopsy, we were able to confirm a final diagnosis of spinal metastasis.

  7. Orthokeratinised odontogenic cyst mimicking periapical cyst.

    Science.gov (United States)

    Rajalakshmi, R; Sreeja, C; Vijayalakshmi, D; Leelarani, V

    2013-10-07

    Orthokeratinised odontogenic cyst (OOC) denotes the odontogenic cyst that microscopically has an orthokeratinised epithelial lining. OOC is characterised by a less-aggressive behaviour and a low rate of recurrence. This report describes a case of OOC involving posterior part of the mandible that mimicked periapical cyst in a 14-year-old boy. The initial clinical diagnosis was given as periapical cyst based on the clinical and radiographical features. Enucleation of the cyst was performed and the specimen was sent for histopathological examination. A definite diagnosis of OOC was made by histopathological examination of the biopsy specimen. This case emphases on including OOC in the differential diagnosis of radiolucencies occurring in the periapical region of non-vital tooth.

  8. Subdural Hematoma Mimickers: A Systematic Review.

    Science.gov (United States)

    Catana, Dragos; Koziarz, Alex; Cenic, Aleksa; Nath, Siddharth; Singh, Sheila; Almenawer, Saleh A; Kachur, Edward

    2016-09-01

    A variety of subdural pathologies that may mimic hematomas are reported in the literature. We aimed to identify the atypical clinical and radiologic presentations of subdural masses that may mimic subdural hematomas. A systematic review of MEDLINE and Embase was conducted independently by 2 reviewers to identify articles describing subdural hematoma mimickers. We also present a patient from our institution with a subdural pathology mimicking a subdural hematoma. We analyzed patient clinical presentations, underlying pathologies, radiologic findings, and clinical outcomes. We included 43 articles totaling 48 patients. The mean ± SD patient age was 55.7 ± 16.8 years. Of the 45 cases describing patient history, 13 patients (27%) had a history of trauma. The underlying pathologies of the 48 subdural collections were 10 metastasis (21%), 14 lymphoma (29%), 7 sarcoma (15%), 4 infectious (8%), 4 autoimmune (8%), and 9 miscellaneous (19%). Findings on computed tomography (CT) scan were 18 hyperdense (41%), 11 hypodense (25%), 9 isodense (20%), 3 isodense/hyperdense (7%), and 3 hypodense/isodense (7%). Thirty-four patients (71%) were treated surgically; among these patients, 65% had symptom resolution. Neither the pathology (P = 0.337) nor the management strategy (P = 0.671) was correlated with improved functional outcomes. Identification of atypical history and radiologic features should prompt further diagnostic tests, including magnetic resonance imaging (MRI), to elucidate the proper diagnosis, given that certain pathologies may be managed nonsurgically. A subdural collection that is hyperdense on CT scan and hyperintense on T2-weighted MRI, along with a history of progressive headache with no trauma, may raise the suspicion of an atypical subdural pathology. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. The Victim Handling Model of Human Trafficking Through Economic Independence

    OpenAIRE

    Nuraeny, Henny; Utami, Tanti Kirana

    2016-01-01

    Human Trafficking is a modern trading of human slavery. Human Trafficking is also one of the worst forms of violation of human dignity that results in trauma to the victims. To that end, there should be a comprehensive treatment for victims. The problems that can be studied is whether a model that can be applied in the treatment of victims of trafficking in Cianjur and disseminating technical how models Handling of Victims of Human Trafficking in Cianjur. This study used normative juridical a...

  10. Molecular Modeling of Prion Transmission to Humans

    Directory of Open Access Journals (Sweden)

    Etienne Levavasseur

    2014-10-01

    Full Text Available Using different prion strains, such as the variant Creutzfeldt-Jakob disease agent and the atypical bovine spongiform encephalopathy agents, and using transgenic mice expressing human or bovine prion protein, we assessed the reliability of protein misfolding cyclic amplification (PMCA to model interspecies and genetic barriers to prion transmission. We compared our PMCA results with in vivo transmission data characterized by attack rates, i.e., the percentage of inoculated mice that developed the disease. Using 19 seed/substrate combinations, we observed that a significant PMCA amplification was only obtained when the mouse line used as substrate is susceptible to the corresponding strain. Our results suggest that PMCA provides a useful tool to study genetic barriers to transmission and to study the zoonotic potential of emerging prion strains.

  11. A Humanized Mouse Model Generated Using Surplus Neonatal Tissue

    Directory of Open Access Journals (Sweden)

    Matthew E. Brown

    2018-04-01

    Full Text Available Summary: Here, we describe the NeoThy humanized mouse model created using non-fetal human tissue sources, cryopreserved neonatal thymus and umbilical cord blood hematopoietic stem cells (HSCs. Conventional humanized mouse models are made by engrafting human fetal thymus and HSCs into immunocompromised mice. These mice harbor functional human T cells that have matured in the presence of human self-peptides and human leukocyte antigen molecules. Neonatal thymus tissue is more abundant and developmentally mature and allows for creation of up to ∼50-fold more mice per donor compared with fetal tissue models. The NeoThy has equivalent frequencies of engrafted human immune cells compared with fetal tissue humanized mice and exhibits T cell function in assays of ex vivo cell proliferation, interferon γ secretion, and in vivo graft infiltration. The NeoThy model may provide significant advantages for induced pluripotent stem cell immunogenicity studies, while bypassing the requirement for fetal tissue. : Corresponding author William Burlingham and colleagues created a humanized mouse model called the NeoThy. The NeoThy uses human neonatal, rather than fetal, tissue sources for generating a human immune system within immunocompromised mouse hosts. NeoThy mice are an attractive alternative to conventional humanized mouse models, as they enable robust and reproducible iPSC immunogenicity experiments in vivo. Keywords: NeoThy, humanized mouse, iPSC, PSC, immunogenicity, transplantation, immunology, hematopoietic stem cells, induced pluripotent stem cells, thymus

  12. Development of Combining of Human Bronchial Mucosa Models with XposeALI® for Exposure of Air Pollution Nanoparticles.

    Directory of Open Access Journals (Sweden)

    Jie Ji

    Full Text Available Exposure to agents via inhalation is of great concerns both in workplace environment and in the daily contact with particles in the ambient air. Reliable human airway exposure systems will most likely replace animal experiment in future toxicity assessment studies of inhaled agents.In this study, we successfully established a combination of an exposure system (XposeALI with 3D models mimicking both healthy and chronic bronchitis-like mucosa by co-culturing human primary bronchial epithelial cells (PBEC and fibroblast at air-liquid interface (ALI. Light-, confocal microscopy, scanning- and transmission electron microscopy, transepithelial electrical resistance (TEER measurement and RT-PCR were performed to identify how the PBEC differentiated under ALI culture condition. Both models were exposed to palladium (Pd nanoparticles which sized 6-10 nm, analogous to those released from modern car catalysts, at three different concentrations utilizing the XposeALI module of the PreciseInhale® exposure system.Exposing the 3D models to Pd nanoparticles induced increased secretion of IL-8, yet the chronic bronchitis-like model released significantly more IL-8 than the normal model. The levels of IL-8 in basal medium (BM and apical lavage medium (AM were in the same ranges, but the secretion of MMP-9 was significantly higher in the AM compared to the BM.This combination of relevant human bronchial mucosa models and sophisticated exposure system can mimic in vivo conditions and serve as a useful alternative animal testing tool when studying adverse effects in humans exposed to aerosols, air pollutants or particles in an occupational setting.

  13. Development of Combining of Human Bronchial Mucosa Models with XposeALI® for Exposure of Air Pollution Nanoparticles.

    Science.gov (United States)

    Ji, Jie; Hedelin, Anna; Malmlöf, Maria; Kessler, Vadim; Seisenbaeva, Gulaim; Gerde, Per; Palmberg, Lena

    2017-01-01

    Exposure to agents via inhalation is of great concerns both in workplace environment and in the daily contact with particles in the ambient air. Reliable human airway exposure systems will most likely replace animal experiment in future toxicity assessment studies of inhaled agents. In this study, we successfully established a combination of an exposure system (XposeALI) with 3D models mimicking both healthy and chronic bronchitis-like mucosa by co-culturing human primary bronchial epithelial cells (PBEC) and fibroblast at air-liquid interface (ALI). Light-, confocal microscopy, scanning- and transmission electron microscopy, transepithelial electrical resistance (TEER) measurement and RT-PCR were performed to identify how the PBEC differentiated under ALI culture condition. Both models were exposed to palladium (Pd) nanoparticles which sized 6-10 nm, analogous to those released from modern car catalysts, at three different concentrations utilizing the XposeALI module of the PreciseInhale® exposure system. Exposing the 3D models to Pd nanoparticles induced increased secretion of IL-8, yet the chronic bronchitis-like model released significantly more IL-8 than the normal model. The levels of IL-8 in basal medium (BM) and apical lavage medium (AM) were in the same ranges, but the secretion of MMP-9 was significantly higher in the AM compared to the BM. This combination of relevant human bronchial mucosa models and sophisticated exposure system can mimic in vivo conditions and serve as a useful alternative animal testing tool when studying adverse effects in humans exposed to aerosols, air pollutants or particles in an occupational setting.

  14. Identification of human operator performance models utilizing time series analysis

    Science.gov (United States)

    Holden, F. M.; Shinners, S. M.

    1973-01-01

    The results of an effort performed by Sperry Systems Management Division for AMRL in applying time series analysis as a tool for modeling the human operator are presented. This technique is utilized for determining the variation of the human transfer function under various levels of stress. The human operator's model is determined based on actual input and output data from a tracking experiment.

  15. Evaluating Models of Human Performance: Safety-Critical Systems Applications

    Science.gov (United States)

    Feary, Michael S.

    2012-01-01

    This presentation is part of panel discussion on Evaluating Models of Human Performance. The purpose of this panel is to discuss the increasing use of models in the world today and specifically focus on how to describe and evaluate models of human performance. My presentation will focus on discussions of generating distributions of performance, and the evaluation of different strategies for humans performing tasks with mixed initiative (Human-Automation) systems. I will also discuss issues with how to provide Human Performance modeling data to support decisions on acceptability and tradeoffs in the design of safety critical systems. I will conclude with challenges for the future.

  16. Integrated Human Futures Modeling in Egypt

    Energy Technology Data Exchange (ETDEWEB)

    Passell, Howard D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Aamir, Munaf Syed [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bernard, Michael Lewis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Beyeler, Walter E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Fellner, Karen Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hayden, Nancy Kay [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jeffers, Robert Fredric [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Keller, Elizabeth James Kistin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Malczynski, Leonard A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mitchell, Michael David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Silver, Emily [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Tidwell, Vincent C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Villa, Daniel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Vugrin, Eric D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Engelke, Peter [Atlantic Council, Washington, D.C. (United States); Burrow, Mat [Atlantic Council, Washington, D.C. (United States); Keith, Bruce [United States Military Academy, West Point, NY (United States)

    2016-01-01

    The Integrated Human Futures Project provides a set of analytical and quantitative modeling and simulation tools that help explore the links among human social, economic, and ecological conditions, human resilience, conflict, and peace, and allows users to simulate tradeoffs and consequences associated with different future development and mitigation scenarios. In the current study, we integrate five distinct modeling platforms to simulate the potential risk of social unrest in Egypt resulting from the Grand Ethiopian Renaissance Dam (GERD) on the Blue Nile in Ethiopia. The five platforms simulate hydrology, agriculture, economy, human ecology, and human psychology/behavior, and show how impacts derived from development initiatives in one sector (e.g., hydrology) might ripple through to affect other sectors and how development and security concerns may be triggered across the region. This approach evaluates potential consequences, intended and unintended, associated with strategic policy actions that span the development-security nexus at the national, regional, and international levels. Model results are not intended to provide explicit predictions, but rather to provide system-level insight for policy makers into the dynamics among these interacting sectors, and to demonstrate an approach to evaluating short- and long-term policy trade-offs across different policy domains and stakeholders. The GERD project is critical to government-planned development efforts in Ethiopia but is expected to reduce downstream freshwater availability in the Nile Basin, fueling fears of negative social and economic impacts that could threaten stability and security in Egypt. We tested these hypotheses and came to the following preliminary conclusions. First, the GERD will have an important short-term impact on water availability, food production, and hydropower production in Egypt, depending on the short- term reservoir fill rate. Second, the GERD will have a very small impact on

  17. Accuracy of stereolithographic models of human anatomy

    International Nuclear Information System (INIS)

    Barker, T.M.; Earwaker, W.J.S.; Lisle, D.A.

    1994-01-01

    A study was undertaken to determine the dimensional accuracy of anatomical replicas derived from X-ray 3D computed tomography (CT) images and produced using the rapid prototyping technique of stereolithography (SLA). A dry bone skull and geometric phantom were scanned, and replicas were produced. Distance measurements were obtained to compare the original objects and the resulting replicas. Repeated measurements between anatomical landmarks were used for comparison of the original skull and replica. Results for the geometric phantom demonstrate a mean difference of +0.47mm, representing an accuracy of 97.7-99.12%. Measurements of the skull produced a range of absolute differences (maximum +4.62mm, minimum +0.1mm, mean +0.85mm). These results support the use of SLA models of human anatomical structures in such areas as pre-operative planning of complex surgical procedures. For applications where higher accuracy is required, improvements can be expected by utilizing smaller pixel resolution in the CT images. Stereolithographic models can now be confidently employed as accurate, three-dimensional replicas of complex, anatomical structures. 14 refs., 2 tabs., 8 figs

  18. Mimicking the extracellular matrix with functionalized, metal-assembled collagen peptide scaffolds.

    Science.gov (United States)

    Hernandez-Gordillo, Victor; Chmielewski, Jean

    2014-08-01

    Natural and synthetic three-dimensional (3-D) scaffolds that mimic the microenvironment of the extracellular matrix (ECM), with growth factor storage/release and the display of cell adhesion signals, offer numerous advantages for regenerative medicine and in vitro morphogenesis and oncogenesis modeling. Here we report the design of collagen mimetic peptides (CMPs) that assemble into a highly crosslinked 3-D matrix in response to metal ion stimuli, that may be functionalized with His-tagged cargoes, such as green fluorescent protein (GFP-His8) and human epidermal growth factor (hEGF-His6). The bound hEGF-His6 was found to gradually release from the matrix in vitro and induce cell proliferation in the EGF-dependent cell line MCF10A. The additional incorporation of a cell adhesion sequence (RGDS) at the N-terminus of the CMP creates an environment that facilitated the organization of matrix-encapsulated MCF10A cells into spheroid structures, thus mimicking the ECM environment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Possible neuro-Sweet disease mimicking brain tumor in the medulla oblongata--case report.

    Science.gov (United States)

    Akiba, Chihiro; Esaki, Takanori; Ando, Maya; Furuya, Tsuyoshi; Noda, Kazuyuki; Nakao, Yasuaki; Yamamoto, Takuji; Okuma, Yasuyuki; Mori, Kentaro

    2011-01-01

    A 62-year-old male presented with a rare case of possible neuro-Sweet Disease (NSD) mimicking brain tumor in the medulla oblongata, manifesting as numbness in the bilateral upper and lower extremities, gait disturbance, dysarthria, and swallowing disturbance which gradually deteriorated over 3 months. Magnetic resonance imaging showed a mass lesion in the medulla oblongata, extending to the upper cervical cord with rim enhancement by gadolinium. The preoperative diagnosis was brain tumor, such as glioma, or inflammatory disease. His neurological symptoms gradually deteriorated, so biopsy was performed through the midline suboccipital approach. Histological examination showed infiltration of inflammatory cells, mainly lymphocytes and macrophages. Human leukocyte antigen typing showed Cw1 and B54 which strongly suggested possible NSD. Steroid pulse therapy was started after surgery and the clinical symptoms improved. Neurosurgeons should be aware of inflammatory disorders such as NSD mimicking brain tumor.

  20. Occupational Neurobrucellosis Mimicking a Brain Tumor: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Hussein Algahtani

    2017-01-01

    Full Text Available Brucellosis is a zoonotic bacterial infection which is transmitted to humans from infected animals and is endemic in many parts of the world including Saudi Arabia. In this article, we report a case of occupational neurobrucellosis that presented with a space-occupying lesion mimicking a brain tumor. We stress on the importance of obtaining detailed social history including occupation to reach the diagnosis in several conditions including brucellosis. We also stress on taking universal precautions when handling any specimens. It may be advisable that manipulation of all unknown specimens arriving at the laboratory should occur in biological safety cabinet until a highly infectious organism is ruled out. Neurobrucellosis should be included in the differential diagnosis in patients presenting with solitary mass lesion mimicking brain tumor especially in endemic areas or high occupational risk group.

  1. Combating Human Trafficking with Deep Multimodal Models

    OpenAIRE

    Tong, Edmund; Zadeh, Amir; Jones, Cara; Morency, Louis-Philippe

    2017-01-01

    Human trafficking is a global epidemic affecting millions of people across the planet. Sex trafficking, the dominant form of human trafficking, has seen a significant rise mostly due to the abundance of escort websites, where human traffickers can openly advertise among at-will escort advertisements. In this paper, we take a major step in the automatic detection of advertisements suspected to pertain to human trafficking. We present a novel dataset called Trafficking-10k, with more than 10,00...

  2. Primary central nervous system lymphoma in an human immunodeficiency virus-infected patient mimicking bilateral eye sign in brain seen in fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography.

    Science.gov (United States)

    Kamaleshwaran, Koramadai Karuppusany; Thirugnanam, Rajasekar; Shibu, Deepu; Kalarikal, Radhakrishnan Edathurthy; Shinto, Ajit Sugunan

    2014-04-01

    Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG PET/CT) has proven useful in the diagnosis, staging, and detection of metastasis and posttreatment monitoring of several malignancies in human immunodeficiency virus (HIV)-infected patients. It also has the ability to make the important distinction between malignancy and infection in the evaluation of central nervous system (CNS) lesions, leading to the initiation of the appropriate treatment and precluding the need for invasive biopsy. We report an interesting case of HIV positive 35-year-old woman presented with headache, disorientation, and decreased level of consciousness. She underwent whole body PET/CT which showed multiple lesions in the cerebrum which mimics bilateral eye in brain. A diagnosis of a primary CNS lymphoma was made and patient was started on chemotherapy.

  3. Primary central nervous system lymphoma in an human immunodeficiency virus-infected patient mimicking bilateral eye sign in brain seen in fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography

    International Nuclear Information System (INIS)

    Kamaleshwaran, Koramadai Karuppusany; Thirugnanam, Rajasekar; Shibu, Deepu; Kalarikal, Radhakrishnan Edathurthy; Shinto, Ajit Sugunan

    2014-01-01

    Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG PET/CT) has proven useful in the diagnosis, staging, and detection of metastasis and posttreatment monitoring of several malignancies in human immunodeficiency virus (HIV)-infected patients. It also has the ability to make the important distinction between malignancy and infection in the evaluation of central nervous system (CNS) lesions, leading to the initiation of the appropriate treatment and precluding the need for invasive biopsy. We report an interesting case of HIV positive 35-year-old woman presented with headache, disorientation, and decreased level of consciousness. She underwent whole body PET/CT which showed multiple lesions in the cerebrum which mimics bilateral eye in brain. A diagnosis of a primary CNS lymphoma was made and patient was started on chemotherapy

  4. Hyperdense dots mimicking microcalcifications : Mammographic findings

    International Nuclear Information System (INIS)

    Kim, Nam Hyeon; Park, Jeong Mi; Goo, Hyun Woo; Bang, Sun Woo

    1996-01-01

    To differentiate fine hyperdense dots mimicking microcalcifications from true microcalcifications on mammography. Mammograms showing hyperdense dots in ten patients (mean age, 59 years) were evaluated. Two radiologists were asked to differentiate with the naked eye the hyperdense dots seen on ten mammograms and proven microcalcifications seen on ten mammograms. Densitometry was also performed for all lesions and the contrast index was calculated. The shape and distribution of the hyperdense dots were evaluated and enquires were made regarding any history of breast disease and corresponding treatment. Biopsies were performed for two patients with hyperdense dots. Two radiologists made correct diagnoses in 19/20 cases(95%). The contrast index was 0.10-0.88 (mean 0.58) for hyperdense dots and 0.02-0.45 (mean 0.17) for true microcalcifications. The hyperdense dots were finer and homogeneously rounder than the microcalcifications. Distribution of the hyperdense dots was more superficial in subcutaneous fat (seven cases) and subareolar area (six cases). All ten patients with hyperdense dots had history of mastitis and abscesses and had been treated by open drainage (six cases) and/or folk remedy (four cases). In eight patients, herb patches had been attached. Biopsies of hyperdense dots did not show any microcalcification or evidence of malignancy. These hyperdense dots were seen mainly in older patients. Their characteristic density, shape, distribution and clinical history makes differential diagnosis from true microcalcifications easy and could reduce unnecessary diagnostic procedures such as surgical biopsy

  5. Hyperdense dots mimicking microcalcifications : Mammographic findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Nam Hyeon; Park, Jeong Mi; Goo, Hyun Woo; Bang, Sun Woo [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    1996-12-01

    To differentiate fine hyperdense dots mimicking microcalcifications from true microcalcifications on mammography. Mammograms showing hyperdense dots in ten patients (mean age, 59 years) were evaluated. Two radiologists were asked to differentiate with the naked eye the hyperdense dots seen on ten mammograms and proven microcalcifications seen on ten mammograms. Densitometry was also performed for all lesions and the contrast index was calculated. The shape and distribution of the hyperdense dots were evaluated and enquires were made regarding any history of breast disease and corresponding treatment. Biopsies were performed for two patients with hyperdense dots. Two radiologists made correct diagnoses in 19/20 cases(95%). The contrast index was 0.10-0.88 (mean 0.58) for hyperdense dots and 0.02-0.45 (mean 0.17) for true microcalcifications. The hyperdense dots were finer and homogeneously rounder than the microcalcifications. Distribution of the hyperdense dots was more superficial in subcutaneous fat (seven cases) and subareolar area (six cases). All ten patients with hyperdense dots had history of mastitis and abscesses and had been treated by open drainage (six cases) and/or folk remedy (four cases). In eight patients, herb patches had been attached. Biopsies of hyperdense dots did not show any microcalcification or evidence of malignancy. These hyperdense dots were seen mainly in older patients. Their characteristic density, shape, distribution and clinical history makes differential diagnosis from true microcalcifications easy and could reduce unnecessary diagnostic procedures such as surgical biopsy.

  6. Mimicking Bone - Chemical and Physical Challenges

    Directory of Open Access Journals (Sweden)

    Sophie C Cox

    2014-08-01

    Full Text Available It is known that chemical and physical features of bone contribute to its functionality, reactivity and mechanical performance. This fundamental rationale underpins the author’s research strategy. This paper presents a summary of efforts to fabricate a synthetic structure, referred to as a scaffold, that both chemically and physical emulates the intricate structure of bone. An understanding of key features of bone tissue that contribute to its remarkable properties is presented as a background to this work. Novel work aimed at improving the understanding of the synthesis of a ceramic biomaterial, namely hydroxyapatite, that is chemically similar to bone mineral is discussed. A case study involving the manufacture of porous scaffolds by 3D printing is also presented. In summary, this article highlights a number of on-going challenges that multidisciplinary tissue engineers aim to solve to get one step closer to mimicking bone, which clinically could improve the quality of life for millions of people worldwide.    Photo credit: By Doc. RNDr. Josef Reischig, CSc. (Author's archive [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0], via Wikimedia Commons

  7. Lymphocitic infundibuloneurohypophysitis mimicking a pituitary adenoma

    Directory of Open Access Journals (Sweden)

    Hubertus Maximilian Mehdorn

    2011-04-01

    Full Text Available A rare case of infundibulo-neurohypophysitis mimicking a pituitary adenoma is presented. A 69-years-old female patient developed polyuria and polydipsia. Laboratory analysis revealed central diabetes insipidus. No hormonal abnormalities. Cranial-magnetic resonance imaging (MRI showed a left sided mass in the adenohypophysis presuming a pituitary adenoma. The mass had contact to both internal carotids. Admission to our department for neurosurgical treatment followed. Ophthalmo - logic examination and neurological examination yielded normal findings. A second MRI focussing on the sellar-region showed a leftsided (T2-MRI.hyperintense, distended adenohypophysis, without contrast enhancement in T1. The stalk appeared thickened. T1- weighted sequences of the neurohypophysis showed loss of signal intensity. We diagnosed an infundibulo-neurohypophysitis and abstai - ned from surgical removal. The patient was discharged under treatment with corticosteroids and desmopressin. Hypophysitis is rare and shows special clinical characteristics. Despite defined radiological features to differentiate between hypophysitis and adenoma the possibility of misdiagnosis, and unnecessary surgical procedures, should always kept in mind.

  8. Indirect carotid cavernous fistula mimicking ocular myasthenia.

    Science.gov (United States)

    Leishangthem, Lakshmi; Satti, Sudhakar Reddy

    2017-10-19

    71-year-old woman with progressive left-sided, monocular diplopia and ptosis. Her symptoms mimicked ocular myasthenia, but she had an indirect carotid cavernous fistula (CCF). She was diagnosed with monocular myasthenia gravis (negative acetylcholinesterase antibody) after a positive ice test and started on Mestinon and underwent a thymectomy complicated by a brachial plexus injury. Months later, she developed left-sided proptosis and ocular bruit. She was urgently referred to neuro-interventional surgery and was diagnosed with an indirect high-flow left CCF, which was treated with Onyx liquid and platinum coil embolisation. Mestinon was discontinued. Her ophthalmic symptoms resolved. However, she was left with a residual left arm and hand hemiparesis and dysmetria secondary to a brachial plexus injury. Indirect CCF usually can present with subtle and progressive symptoms leading to delayed diagnosis or misdiagnosis. It is important for ophthalmologists to consider this differential in a patient with progressive ocular symptoms. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  9. Microfabricated adhesive mimicking gecko foot-hair

    Science.gov (United States)

    Geim, A. K.; Dubonos, S. V.; Grigorieva, I. V.; Novoselov, K. S.; Zhukov, A. A.; Shapoval, S. Yu.

    2003-07-01

    The amazing climbing ability of geckos has attracted the interest of philosophers and scientists alike for centuries. However, only in the past few years has progress been made in understanding the mechanism behind this ability, which relies on submicrometre keratin hairs covering the soles of geckos. Each hair produces a miniscule force ~10-7 N (due to van der Waals and/or capillary interactions) but millions of hairs acting together create a formidable adhesion of ~10 N cm-2: sufficient to keep geckos firmly on their feet, even when upside down on a glass ceiling. It is very tempting to create a new type of adhesive by mimicking the gecko mechanism. Here we report on a prototype of such 'gecko tape' made by microfabrication of dense arrays of flexible plastic pillars, the geometry of which is optimized to ensure their collective adhesion. Our approach shows a way to manufacture self-cleaning, re-attachable dry adhesives, although problems related to their durability and mass production are yet to be resolved.

  10. Schwannoma of the left brachial plexus mimicking a ...

    African Journals Online (AJOL)

    Schwannoma of the left brachial plexus mimicking a cervicomediastinal ... Her voice was hoarse but there was no eye signs suggestive of thyrotoxicosis. ... A presumptive diagnosis of thyroid carcinoma with retrosternal extension was made.

  11. Deep Granuloma Annulare Mimicking Inflamed Cysts in a Teenager.

    Science.gov (United States)

    Guo, Emily L; Degesys, Catherine A; Jahan-Tigh, Richard; Chan, Audrey

    2017-07-01

    We describe deep granuloma annulare (DGA) of the forehead mimicking inflamed cysts. Reactive inflammation and sterile purulent drainage may be an underrecognized feature of DGA. © 2017 Wiley Periodicals, Inc.

  12. Synchrony and motor mimicking in chimpanzee observational learning.

    Science.gov (United States)

    Fuhrmann, Delia; Ravignani, Andrea; Marshall-Pescini, Sarah; Whiten, Andrew

    2014-06-13

    Cumulative tool-based culture underwrote our species' evolutionary success, and tool-based nut-cracking is one of the strongest candidates for cultural transmission in our closest relatives, chimpanzees. However the social learning processes that may explain both the similarities and differences between the species remain unclear. A previous study of nut-cracking by initially naïve chimpanzees suggested that a learning chimpanzee holding no hammer nevertheless replicated hammering actions it witnessed. This observation has potentially important implications for the nature of the social learning processes and underlying motor coding involved. In the present study, model and observer actions were quantified frame-by-frame and analysed with stringent statistical methods, demonstrating synchrony between the observer's and model's movements, cross-correlation of these movements above chance level and a unidirectional transmission process from model to observer. These results provide the first quantitative evidence for motor mimicking underlain by motor coding in apes, with implications for mirror neuron function.

  13. Synchrony and motor mimicking in chimpanzee observational learning

    Science.gov (United States)

    Fuhrmann, Delia; Ravignani, Andrea; Marshall-Pescini, Sarah; Whiten, Andrew

    2014-01-01

    Cumulative tool-based culture underwrote our species' evolutionary success, and tool-based nut-cracking is one of the strongest candidates for cultural transmission in our closest relatives, chimpanzees. However the social learning processes that may explain both the similarities and differences between the species remain unclear. A previous study of nut-cracking by initially naïve chimpanzees suggested that a learning chimpanzee holding no hammer nevertheless replicated hammering actions it witnessed. This observation has potentially important implications for the nature of the social learning processes and underlying motor coding involved. In the present study, model and observer actions were quantified frame-by-frame and analysed with stringent statistical methods, demonstrating synchrony between the observer's and model's movements, cross-correlation of these movements above chance level and a unidirectional transmission process from model to observer. These results provide the first quantitative evidence for motor mimicking underlain by motor coding in apes, with implications for mirror neuron function. PMID:24923651

  14. Recapitulation of spinal motor neuron-specific disease phenotypes in a human cell model of spinal muscular atrophy

    Institute of Scientific and Technical Information of China (English)

    Zhi-Bo Wang; Xiaoqing Zhang; Xue-Jun Li

    2013-01-01

    Establishing human cell models of spinal muscular atrophy (SMA) to mimic motor neuron-specific phenotypes holds the key to understanding the pathogenesis of this devastating disease.Here,we developed a closely representative cell model of SMA by knocking down the disease-determining gene,survival motor neuron (SMN),in human embryonic stem cells (hESCs).Our study with this cell model demonstrated that knocking down of SMN does not interfere with neural induction or the initial specification of spinal motor neurons.Notably,the axonal outgrowth of spinal motor neurons was significantly impaired and these disease-mimicking neurons subsequently degenerated.Furthermore,these disease phenotypes were caused by SMN-full length (SMN-FL) but not SMN-A7 (lacking exon 7)knockdown,and were specific to spinal motor neurons.Restoring the expression of SMN-FL completely ameliorated all of the disease phenotypes,including specific axonal defects and motor neuron loss.Finally,knockdown of SMNFL led to excessive mitochondrial oxidative stress in human motor neuron progenitors.The involvement of oxidative stress in the degeneration of spinal motor neurons in the SMA cell model was further confirmed by the administration of N-acetylcysteine,a potent antioxidant,which prevented disease-related apoptosis and subsequent motor neuron death.Thus,we report here the successful establishment of an hESC-based SMA model,which exhibits disease gene isoform specificity,cell type specificity,and phenotype reversibility.Our model provides a unique paradigm for studying how motor neurons specifically degenerate and highlights the potential importance of antioxidants for the treatment of SMA.

  15. A long term model of circulation. [human body

    Science.gov (United States)

    White, R. J.

    1974-01-01

    A quantitative approach to modeling human physiological function, with a view toward ultimate application to long duration space flight experiments, was undertaken. Data was obtained on the effect of weightlessness on certain aspects of human physiological function during 1-3 month periods. Modifications in the Guyton model are reviewed. Design considerations for bilateral interface models are discussed. Construction of a functioning whole body model was studied, as well as the testing of the model versus available data.

  16. A sample application of nuclear power human resources model

    International Nuclear Information System (INIS)

    Gurgen, A.; Ergun, S.

    2016-01-01

    One of the most important issues for a new comer country initializing the nuclear power plant projects is to have both quantitative and qualitative models for the human resources development. For the quantitative model of human resources development for Turkey, “Nuclear Power Human Resources (NPHR) Model” developed by the Los Alamos National Laboratory was used to determine the number of people that will be required from different professional or occupational fields in the planning of human resources for Akkuyu, Sinop and the third nuclear power plant projects. The number of people required for different professions for the Nuclear Energy Project Implementation Department, the regulatory authority, project companies, construction, nuclear power plants and the academy were calculated. In this study, a sample application of the human resources model is presented. The results of the first tries to calculate the human resources needs of Turkey were obtained. Keywords: Human Resources Development, New Comer Country, NPHR Model

  17. Molecular mechanism of ocular surface damage: application to an in vitro dry eye model on human corneal epithelium.

    Science.gov (United States)

    Meloni, Marisa; De Servi, Barbara; Marasco, Daniela; Del Prete, Salvatore

    2011-01-12

    The present study was concerned with the development of a new experimental model of dry eye using human reconstructed in vitro corneal epithelium (HCE). The model is based on the use of adapted culture conditions that induce relevant modifications at the cellular and molecular level thus mimicking dry eye. The HCE model was maintained in a controlled environmental setting (relative humidity eye. The evolution of the dry eye condition was assessed by histology, immunohistochemistry staining, scanning electron microscopy, and gene expression by using TaqMan gene assay technology (mucin-4 [MUC4], matrix metallopeptidase-9 [MMP9], tumor necrosis factor-α [TNF-α], and defensin β-2 [DEFB2). The effects of different commercially available tear substitutes on the induced dry eye condition were tested. This in vitro dry eye HCE model, that was well established within 24 h, has the characteristic features of a dry eye epithelium and could be satisfactorily used for preliminary assessment of the protective activity of some artificial tears. The transcriptional study of selected biomarkers showed an increase in MUC4, MMP9, TNF-α, and hBD-2 (DEFB2) gene expression. By using a dynamic approach, we were able to define a biomarker gene signature of dry eye-induced effects that could be predictive of corneal damage in vivo and to discriminate the efficacy among different commercial artificial tears.

  18. Competency Modeling in Extension Education: Integrating an Academic Extension Education Model with an Extension Human Resource Management Model

    Science.gov (United States)

    Scheer, Scott D.; Cochran, Graham R.; Harder, Amy; Place, Nick T.

    2011-01-01

    The purpose of this study was to compare and contrast an academic extension education model with an Extension human resource management model. The academic model of 19 competencies was similar across the 22 competencies of the Extension human resource management model. There were seven unique competencies for the human resource management model.…

  19. A model of the human retina

    DEFF Research Database (Denmark)

    Jørgensen, John Leif

    1998-01-01

    Traditionally, the human eye is perceived as being "just" a camera, that renders an accurate, although limited, image for processing in the brain. This interpretation probably stems from the apparent similarity between a video- or photo-camera and a human eye with respect to the lens, the iris...

  20. Toxicology Analysis of Tissue-Mimicking Phantom Made From Gelatin

    Science.gov (United States)

    Dolbashid, A. S.; Hamzah, N.; Zaman, W. S. W. K.; Mokhtar, M. S.

    2017-06-01

    Skin phantom mimics the biological skin tissues as it have the ability to respond to changes in its environment. The development of tissue-mimicking phantom could contributes towards the reduce usage of animal in cosmetics and pharmacokinetics. In this study, the skin phantoms made from gelatin were tested with four different commonly available cosmetic products to determine the toxicity of each substance. The four substances used were; mercury-based whitening face cream, carcinogenic liquid make-up foundation, paraben-based acne cleanser, and organic lip balm. Toxicity test were performed on all of the phantoms. For toxicity testing, topographical and electrophysiological changes of the phantoms were evaluated. The ability of each respective phantom to react with mild toxic substances and its electrical resistance were analysed in to determine the toxicity of all the phantom models. Four-electrode method along with custom made electrical impedance analyser was used to differentiate electrical resistance between intoxicated phantom and non-intoxicated phantom in this study. Electrical resistance values obtained from the phantom models were significantly higher than the control group. The result obtained suggests the phantom as a promising candidate to be used as alternative for toxicology testing in the future.

  1. Modelling human emotions for tactical decision-making games

    NARCIS (Netherlands)

    Visschedijk, G.; Lazonder, Adrianus W.; van der Hulst, A.; Vink, N.; Leemkuil, Hendrik H.

    2013-01-01

    The training of tactical decision making increasingly occurs through serious computer games. A challenging aspect of designing such games is the modelling of human emotions. Two studies were performed to investigate the relation between fidelity and human emotion recognition in virtual human

  2. Modelling human emotions for tactical decision-making games

    NARCIS (Netherlands)

    Visschedijk, G.C.; Lazonder, A.W.; Hulst, A.H. van der; Vink, N.; Leemkuil, H.

    2013-01-01

    The training of tactical decision making increasingly occurs through serious computer games. A challenging aspect of designing such games is the modelling of human emotions. Two studieswere performed to investigate the relation between fidelity and human emotion recognition in virtual human

  3. Modelling Human Emotions for Tactical Decision-Making Games

    Science.gov (United States)

    Visschedijk, Gillian C.; Lazonder, Ard W.; van der Hulst, Anja; Vink, Nathalie; Leemkuil, Henny

    2013-01-01

    The training of tactical decision making increasingly occurs through serious computer games. A challenging aspect of designing such games is the modelling of human emotions. Two studies were performed to investigate the relation between fidelity and human emotion recognition in virtual human characters. Study 1 compared five versions of a virtual…

  4. Modelling dynamic human-device interaction in healthcare

    OpenAIRE

    Niezen, Gerrit

    2013-01-01

    Errors are typically blamed on human factors, forgetting that the system should have been designed to take them into account and minimise these problems. In our research we are developing tools to design interactive medical devices using human-in-the-loop modelling. Manual control theory is used to describe and analyse the dynamic aspects of human-device interaction.

  5. Minimizing Human Risk: Human Performance Models in the Space Human Factors and Habitability and Behavioral Health and Performance Elements

    Science.gov (United States)

    Gore, Brian F.

    2016-01-01

    Human space exploration has never been more exciting than it is today. Human presence to outer worlds is becoming a reality as humans are leveraging much of our prior knowledge to the new mission of going to Mars. Exploring the solar system at greater distances from Earth than ever before will possess some unique challenges, which can be overcome thanks to the advances in modeling and simulation technologies. The National Aeronautics and Space Administration (NASA) is at the forefront of exploring our solar system. NASA's Human Research Program (HRP) focuses on discovering the best methods and technologies that support safe and productive human space travel in the extreme and harsh space environment. HRP uses various methods and approaches to answer questions about the impact of long duration missions on the human in space including: gravity's impact on the human body, isolation and confinement on the human, hostile environments impact on the human, space radiation, and how the distance is likely to impact the human. Predictive models are included in the HRP research portfolio as these models provide valuable insights into human-system operations. This paper will provide an overview of NASA's HRP and will present a number of projects that have used modeling and simulation to provide insights into human-system issues (e.g. automation, habitat design, schedules) in anticipation of space exploration.

  6. Invasive Pulmonary Aspergillosis-mimicking Tuberculosis.

    Science.gov (United States)

    Kim, Sung-Han; Kim, Mi Young; Hong, Sun In; Jung, Jiwon; Lee, Hyun Joo; Yun, Sung-Cheol; Lee, Sang-Oh; Choi, Sang-Ho; Kim, Yang Soo; Woo, Jun Hee

    2015-07-01

    Pulmonary tuberculosis is occasionally confused with invasive pulmonary aspergillosis (IPA) in transplant recipients, since clinical suspicion and early diagnosis of pulmonary tuberculosis and IPA rely heavily on imaging modes such as computed tomography (CT). We therefore investigated IPA-mimicking tuberculosis in transplant recipients. All adult transplant recipients who developed tuberculosis or IPA at a tertiary hospital in an intermediate tuberculosis-burden country during a 6-year period were enrolled. First, we tested whether experienced radiologists could differentiate pulmonary tuberculosis from IPA. Second, we determined which radiologic findings could help us differentiate them. During the study period, 28 transplant recipients developed pulmonary tuberculosis after transplantation, and 80 patients developed IPA after transplantation. Two experienced radiologists scored blindly 28 tuberculosis and 50 randomly selected IPA cases. The sensitivities of radiologists A and B for IPA were 78% and 68%, respectively (poor agreement, kappa value = 0.25). The sensitivities of radiologists A and B for tuberculosis were 64% and 61%, respectively (excellent agreement, kappa value = 0.77). We then compared the CT findings of the 28 patients with tuberculosis and 80 patients with IPA. Infarct-shaped consolidations and smooth bronchial wall thickening were more frequent in IPA, and mass-shaped consolidations and centrilobular nodules (tuberculosis. Certain CT findings appear to be helpful in differentiating between IPA and tuberculosis. Nevertheless, the CT findings of about one-third of pulmonary tuberculosis cases in transplant recipients are very close to those of IPA. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  7. Bio-Inspired PVDF-Based, Mouse Whisker Mimicking, Tactile Sensor

    Directory of Open Access Journals (Sweden)

    Mohsin Islam Tiwana

    2016-10-01

    Full Text Available The design and fabrication of a Polyvinylidene fluoride (PVDF based, mouse (or rodent whisker mimicking, tactile sensor is presented. Unlike previous designs reported in the literature, this sensor mimics the mouse whisker not only mechanically, but it also makes macro movements just like a real mouse whisker in a natural environment. We have developed a mathematical model and performed finite element analysis using COMSOL, in order to optimise the whisker to have the same natural frequency as that of a biological whisker. Similarly, we have developed a control system that enables the whisker mimicking sensor to vibrate at variable frequencies and conducted practical experiments to validate the response of the sensor. The natural frequency of the whisker can be designed anywhere between 35 and 110 Hz, the same as a biological whisker, by choosing different materials and physical dimensions. The control system of this sensor enables the whisker to vibrate between 5 and 236 Hz.

  8. Engineering a 3D-Bioprinted Model of Human Heart Valve Disease Using Nanoindentation-Based Biomechanics

    Directory of Open Access Journals (Sweden)

    Dewy C. van der Valk

    2018-05-01

    Full Text Available In calcific aortic valve disease (CAVD, microcalcifications originating from nanoscale calcifying vesicles disrupt the aortic valve (AV leaflets, which consist of three (biomechanically distinct layers: the fibrosa, spongiosa, and ventricularis. CAVD has no pharmacotherapy and lacks in vitro models as a result of complex valvular biomechanical features surrounding resident mechanosensitive valvular interstitial cells (VICs. We measured layer-specific mechanical properties of the human AV and engineered a three-dimensional (3D-bioprinted CAVD model that recapitulates leaflet layer biomechanics for the first time. Human AV leaflet layers were separated by microdissection, and nanoindentation determined layer-specific Young’s moduli. Methacrylated gelatin (GelMA/methacrylated hyaluronic acid (HAMA hydrogels were tuned to duplicate layer-specific mechanical characteristics, followed by 3D-printing with encapsulated human VICs. Hydrogels were exposed to osteogenic media (OM to induce microcalcification, and VIC pathogenesis was assessed by near infrared or immunofluorescence microscopy. Median Young’s moduli of the AV layers were 37.1, 15.4, and 26.9 kPa (fibrosa/spongiosa/ventricularis, respectively. The fibrosa and spongiosa Young’s moduli matched the 3D 5% GelMa/1% HAMA UV-crosslinked hydrogels. OM stimulation of VIC-laden bioprinted hydrogels induced microcalcification without apoptosis. We report the first layer-specific measurements of human AV moduli and a novel 3D-bioprinted CAVD model that potentiates microcalcification by mimicking the native AV mechanical environment. This work sheds light on valvular mechanobiology and could facilitate high-throughput drug-screening in CAVD.

  9. Symbolic modeling of human anatomy for visualization and simulation

    Science.gov (United States)

    Pommert, Andreas; Schubert, Rainer; Riemer, Martin; Schiemann, Thomas; Tiede, Ulf; Hoehne, Karl H.

    1994-09-01

    Visualization of human anatomy in a 3D atlas requires both spatial and more abstract symbolic knowledge. Within our 'intelligent volume' model which integrates these two levels, we developed and implemented a semantic network model for describing human anatomy. Concepts for structuring (abstraction levels, domains, views, generic and case-specific modeling, inheritance) are introduced. Model, tools for generation and exploration and applications in our 3D anatomical atlas are presented and discussed.

  10. Pharmacological migraine provocation: a human model of migraine

    DEFF Research Database (Denmark)

    Ashina, Messoud; Hansen, Jakob Møller

    2010-01-01

    for migraine mechanisms. So far, however, animal models cannot predict the efficacy of new therapies for migraine. Because migraine attacks are fully reversible and can be aborted by therapy, the headache- or migraine-provoking property of naturally occurring signaling molecules can be tested in a human model....... If a naturally occurring substance can provoke migraine in human patients, then it is likely, although not certain, that blocking its effect will be effective in the treatment of acute migraine attacks. To this end, a human in vivo model of experimental headache and migraine in humans has been developed...

  11. Humanized in vivo Model for Autoimmune Diabetes

    National Research Council Canada - National Science Library

    Nepom, Gerald T; Gebe, John A

    2008-01-01

    The CD4+ T cell response is critical for cellular autoimmunity in human T1D, but incomplete understanding of issues of specific cell frequency, avidity, function, and correlation with disease status presents...

  12. Animal models for human genetic diseases | Sharif | African Journal ...

    African Journals Online (AJOL)

    The study of human genetic diseases can be greatly aided by animal models because of their similarity to humans in terms of genetics. In addition to understand diverse aspects of basic biology, model organisms are extensively used in applied research in agriculture, industry, and also in medicine, where they are used to ...

  13. Humanized mouse model for assessing the human immune response to xenogeneic and allogeneic decellularized biomaterials.

    Science.gov (United States)

    Wang, Raymond M; Johnson, Todd D; He, Jingjin; Rong, Zhili; Wong, Michelle; Nigam, Vishal; Behfar, Atta; Xu, Yang; Christman, Karen L

    2017-06-01

    Current assessment of biomaterial biocompatibility is typically implemented in wild type rodent models. Unfortunately, different characteristics of the immune systems in rodents versus humans limit the capability of these models to mimic the human immune response to naturally derived biomaterials. Here we investigated the utility of humanized mice as an improved model for testing naturally derived biomaterials. Two injectable hydrogels derived from decellularized porcine or human cadaveric myocardium were compared. Three days and one week after subcutaneous injection, the hydrogels were analyzed for early and mid-phase immune responses, respectively. Immune cells in the humanized mouse model, particularly T-helper cells, responded distinctly between the xenogeneic and allogeneic biomaterials. The allogeneic extracellular matrix derived hydrogels elicited significantly reduced total, human specific, and CD4 + T-helper cell infiltration in humanized mice compared to xenogeneic extracellular matrix hydrogels, which was not recapitulated in wild type mice. T-helper cells, in response to the allogeneic hydrogel material, were also less polarized towards a pro-remodeling Th2 phenotype compared to xenogeneic extracellular matrix hydrogels in humanized mice. In both models, both biomaterials induced the infiltration of macrophages polarized towards a M2 phenotype and T-helper cells polarized towards a Th2 phenotype. In conclusion, these studies showed the importance of testing naturally derived biomaterials in immune competent animals and the potential of utilizing this humanized mouse model for further studying human immune cell responses to biomaterials in an in vivo environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Advanced Video Activity Analytics (AVAA): Human Performance Model Report

    Science.gov (United States)

    2017-12-01

    effectively. The goal of the modeling effort is to provide an understanding of the current state of the system with respect to the impact on human ...representation of the human ‒ machine system. Third, task network modeling is relatively easy to use and understand . Lastly, it is more cost effective and can...and communication issues. Proceedings of the Human Factors and Ergonomics Society Annual Meeting. 2006;48(2):2396–2400. Reid GB, Colle HA

  15. Specific and General Human Capital in an Endogenous Growth Model

    OpenAIRE

    Evangelia Vourvachaki; Vahagn Jerbashian; : Sergey Slobodyan

    2014-01-01

    In this article, we define specific (general) human capital in terms of the occupations whose use is spread in a limited (wide) set of industries. We analyze the growth impact of an economy's composition of specific and general human capital, in a model where education and research and development are costly and complementary activities. The model suggests that a declining share of specific human capital, as observed in the Czech Republic, can be associated with a lower rate of long-term grow...

  16. Dynamic Simulation of Human Gait Model With Predictive Capability.

    Science.gov (United States)

    Sun, Jinming; Wu, Shaoli; Voglewede, Philip A

    2018-03-01

    In this paper, it is proposed that the central nervous system (CNS) controls human gait using a predictive control approach in conjunction with classical feedback control instead of exclusive classical feedback control theory that controls based on past error. To validate this proposition, a dynamic model of human gait is developed using a novel predictive approach to investigate the principles of the CNS. The model developed includes two parts: a plant model that represents the dynamics of human gait and a controller that represents the CNS. The plant model is a seven-segment, six-joint model that has nine degrees-of-freedom (DOF). The plant model is validated using data collected from able-bodied human subjects. The proposed controller utilizes model predictive control (MPC). MPC uses an internal model to predict the output in advance, compare the predicted output to the reference, and optimize the control input so that the predicted error is minimal. To decrease the complexity of the model, two joints are controlled using a proportional-derivative (PD) controller. The developed predictive human gait model is validated by simulating able-bodied human gait. The simulation results show that the developed model is able to simulate the kinematic output close to experimental data.

  17. Establishment of a Model of Microencapsulated SGC7901 Human Gastric Carcinoma Cells Cocultured with Tumor-Associated Macrophages

    Directory of Open Access Journals (Sweden)

    Jin-Ming Zhu

    2018-01-01

    Full Text Available The important factors of poor survival of gastric cancer (GC are relapse and metastasis. For further elucidation of the mechanism, a culture system mimicking the microenvironment of the tumor in humans was needed. We established a model of microencapsulated SGC7901 human GC cells and evaluated the effects of coculturing spheres with tumor-associated macrophages (TAMs. SGC7901 cells were encapsulated in alginate-polylysine-sodium alginate (APA microcapsules using an electrostatic droplet generator. MTT assays showed that the numbers of microencapsulated cells were the highest after culturing for 14 days. Metabolic curves showed consumption of glucose and production of lactic acid by day 20. Immunocytochemistry confirmed that Proliferating Cell Nuclear Antigen (PCNA and Vascular Endothelial Growth Factor (VEGF were expressed in microencapsulated SGC7901 cells on days 7 and 14. The expression of PCNA was observed outside spheroids; however, VEGF was found in the entire spheroids. PCNA and VEGF were increased after being cocultured with TAMs. Matrix metalloproteinase-2 (MMP-2 and matrix metalloproteinase-9 (MMP-9 expressions were detected in the supernatant of microencapsulated cells cocultured with TAMs but not in microencapsulated cells. Our study confirms the successful establishment of the microencapsulated GC cells. TAMs can promote PCNA, VEGF, MMP-2, and MMP-9 expressions of the GC cells.

  18. Moderately nonlinear ultrasound propagation in blood-mimicking fluid.

    Science.gov (United States)

    Kharin, Nikolay A; Vince, D Geoffrey

    2004-04-01

    In medical diagnostic ultrasound (US), higher than-in-water nonlinearity of body fluids and tissue usually does not produce strong nonlinearly distorted waves because of the high absorption. The relative influence of absorption and nonlinearity can be characterized by the Gol'dberg number Gamma. There are two limiting cases in nonlinear acoustics: weak waves (Gamma 1). However, at diagnostic frequencies in tissue and body fluids, the nonlinear effects and effects of absorption more likely are comparable (Gol'dberg number Gamma approximately 1). The aim of this work was to study the nonlinear propagation of a moderately nonlinear US second harmonic signal in a blood-mimicking fluid. Quasilinear solutions to the KZK equation are presented, assuming radiation from a flat and geometrically focused circular Gaussian source. The solutions are expressed in a new simplified closed form and are in very good agreement with those of previous studies measuring and modeling Gaussian beams. The solutions also show good agreement with the measurements of the beams produced by commercially available transducers, even without special Gaussian shading.

  19. Variation in calculated human exposure. Comparison of calculations with seven European human exposure models

    NARCIS (Netherlands)

    Swartjes F; ECO

    2003-01-01

    Twenty scenarios, differing with respect to land use, soil type and contaminant, formed the basis for calculating human exposure from soil contaminants with the use of models contributed by seven European countries (one model per country). Here, the human exposures to children and children

  20. Incorporation of human factors into ship collision risk models focusing on human centred design aspects

    International Nuclear Information System (INIS)

    Sotiralis, P.; Ventikos, N.P.; Hamann, R.; Golyshev, P.; Teixeira, A.P.

    2016-01-01

    This paper presents an approach that more adequately incorporates human factor considerations into quantitative risk analysis of ship operation. The focus is on the collision accident category, which is one of the main risk contributors in ship operation. The approach is based on the development of a Bayesian Network (BN) model that integrates elements from the Technique for Retrospective and Predictive Analysis of Cognitive Errors (TRACEr) and focuses on the calculation of the collision accident probability due to human error. The model takes into account the human performance in normal, abnormal and critical operational conditions and implements specific tasks derived from the analysis of the task errors leading to the collision accident category. A sensitivity analysis is performed to identify the most important contributors to human performance and ship collision. Finally, the model developed is applied to assess the collision risk of a feeder operating in Dover strait using the collision probability estimated by the developed BN model and an Event tree model for calculation of human, economic and environmental risks. - Highlights: • A collision risk model for the incorporation of human factors into quantitative risk analysis is proposed. • The model takes into account the human performance in different operational conditions leading to the collision. • The most important contributors to human performance and ship collision are identified. • The model developed is applied to assess the collision risk of a feeder operating in Dover strait.

  1. QSAR models of human data can enrich or replace LLNA testing for human skin sensitization

    OpenAIRE

    Alves, Vinicius M.; Capuzzi, Stephen J.; Muratov, Eugene; Braga, Rodolpho C.; Thornton, Thomas; Fourches, Denis; Strickland, Judy; Kleinstreuer, Nicole; Andrade, Carolina H.; Tropsha, Alexander

    2016-01-01

    Skin sensitization is a major environmental and occupational health hazard. Although many chemicals have been evaluated in humans, there have been no efforts to model these data to date. We have compiled, curated, analyzed, and compared the available human and LLNA data. Using these data, we have developed reliable computational models and applied them for virtual screening of chemical libraries to identify putative skin sensitizers. The overall concordance between murine LLNA and human skin ...

  2. Autoimmunity to Tropomyosin-Specific Peptides Induced by Mycobacterium leprae in Leprosy Patients: Identification of Mimicking Proteins.

    Science.gov (United States)

    Singh, Itu; Yadav, Asha Ram; Mohanty, Keshar Kunja; Katoch, Kiran; Sharma, Prashant; Pathak, Vinay Kumar; Bisht, Deepa; Gupta, Umesh D; Sengupta, Utpal

    2018-01-01

    It has been shown earlier that there is a rise in the levels of autoantibodies and T cell response to cytoskeletal proteins in leprosy. Our group recently demonstrated a rise in both T and B cell responses to keratin and myelin basic protein in all types of leprosy patients and their associations in type 1 reaction (T1R) group of leprosy. In this study, we investigated the association of levels of autoantibodies and lymphoproliferation against myosin in leprosy patients across the spectrum and tried to find out the mimicking proteins or epitopes between host protein and protein/s of Mycobacterium leprae . One hundred and sixty-nine leprosy patients and 55 healthy controls (HC) were enrolled in the present study. Levels of anti-myosin antibodies and T-cell responses against myosin were measured by ELISA and lymphoproliferation assay, respectively. Using 2-D gel electrophoresis, western blot and MALDI-TOF/TOF antibody-reactive spots were identified. Three-dimensional structure of mimicking proteins was modeled by online server. B cell epitopes of the proteins were predicted by BCPREDS server 1.0 followed by identification of mimicking epitopes. Mice of inbred BALB/c strain were hyperimmunized with M. leprae soluble antigen (MLSA) and splenocytes and lymph node cells of these animals were adoptively transferred to naïve mice. Highest level of anti-myosin antibodies was noted in sera of T1R leprosy patients. We observed significantly higher levels of lymphoproliferative response ( p  leprae . We found four mimicking epitopes between these sequences. These data suggest that these mimicking proteins tropomyosin and ATP-dependent Clp protease ATP-binding subunit of M. leprae or more precisely mimicking epitopes (four B cell epitopes) might be responsible for extensive tissue damage during type1 reaction in leprosy.

  3. Mouse models for understanding human developmental anomalies

    International Nuclear Information System (INIS)

    Generoso, W.M.

    1989-01-01

    The mouse experimental system presents an opportunity for studying the nature of the underlying mutagenic damage and the molecular pathogenesis of this class of anomalies by virtue of the accessibility of the zygote and its descendant blastomeres. Such studies could contribute to the understanding of the etiology of certain sporadic but common human malformations. The vulnerability of the zygotes to mutagens as demonstrated in the studies described in this report should be a major consideration in chemical safety evaluation. It raises questions regarding the danger to human zygotes when the mother is exposed to drugs and environmental chemicals

  4. Lessons learned from HRA and human-system modeling efforts

    International Nuclear Information System (INIS)

    Hallbert, B.P.

    1993-01-01

    Human-System modeling is not unique to the field of Human Reliability Analysis (HRA). Since human factors professionals first began their explorations of human activities, they have done so with the concept of open-quotes systemclose quotes in mind. Though the two - human and system - are distinct, they can be properly understood only in terms of each other: the system provides a context in which goals and objectives for work are defined, and the human plays either a pre-defined or ad hoc role in meeting these goals. In this sense, every intervention which attempts to evaluate or improve upon some system parameter requires that an understanding of human-system interactions be developed. It is too often the case, however, that somewhere between the inception of a system and its implementation, the human-system relationships are overlooked, misunderstood, or inadequately framed. This results in mismatches between demands versus capabilities of human operators, systems which are difficult to operate, and the obvious end product-human error. The lessons learned from human system modeling provide a valuable feedback mechanism to the process of HRA, and the technologies which employ this form of modeling

  5. Advances and perspectives in in vitro human gut fermentation modeling.

    Science.gov (United States)

    Payne, Amanda N; Zihler, Annina; Chassard, Christophe; Lacroix, Christophe

    2012-01-01

    The gut microbiota is a highly specialized organ containing host-specific assemblages of microbes whereby metabolic activity directly impacts human health and disease. In vitro gut fermentation models present an unmatched opportunity of performing studies frequently challenged in humans and animals owing to ethical concerns. Multidisciplinary systems biology analyses supported by '-omics' platforms remain widely neglected in the field of in vitro gut fermentation modeling but are key to advancing the significance of these models. Model-driven experimentation using a combination of in vitro gut fermentation and in vitro human cell models represent an advanced approach in identifying complex host-microbe interactions and niches central to gut fermentation processes. The aim of this review is to highlight the advances and challenges exhibited by in vitro human gut fermentation modeling. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Human immune system mouse models of Ebola virus infection.

    Science.gov (United States)

    Spengler, Jessica R; Prescott, Joseph; Feldmann, Heinz; Spiropoulou, Christina F

    2017-08-01

    Human immune system (HIS) mice, immunodeficient mice engrafted with human cells (with or without donor-matched tissue), offer a unique opportunity to study pathogens that cause disease predominantly or exclusively in humans. Several HIS mouse models have recently been used to study Ebola virus (EBOV) infection and disease. The results of these studies are encouraging and support further development and use of these models in Ebola research. HIS mice provide a small animal model to study EBOV isolates, investigate early viral interactions with human immune cells, screen vaccines and therapeutics that modulate the immune system, and investigate sequelae in survivors. Here we review existing models, discuss their use in pathogenesis studies and therapeutic screening, and highlight considerations for study design and analysis. Finally, we point out caveats to current models, and recommend future efforts for modeling EBOV infection in HIS mice. Published by Elsevier B.V.

  7. Encapsulated human hepatocellular carcinoma cells by alginate gel beads as an in vitro metastasis model

    International Nuclear Information System (INIS)

    Xu, Xiao-xi; Liu, Chang; Liu, Yang; Li, Nan; Guo, Xin; Wang, Shu-jun; Sun, Guang-wei; Wang, Wei; Ma, Xiao-jun

    2013-01-01

    Hepatocellular carcinoma (HCC) is the most common primary liver cancer and often forms metastases, which are the most important prognostic factors. For further elucidation of the mechanism underlying the progression and metastasis of HCC, a culture system mimicking the in vivo tumor microenvironment is needed. In this study, we investigated the metastatic ability of HCC cells cultured within alginate gel (ALG) beads. In the culture system, HCC cells formed spheroids by proliferation and maintained in nuclear abnormalities. The gene and protein expression of metastasis-related molecules was increased in ALG beads, compared with the traditional adhesion culture. Furthermore, several gene expression levels in ALG bead culture system were even closer to liver cancer tissues. More importantly, in vitro invasion assay showed that the invasion cells derived from ALG beads was 7.8-fold higher than adhesion cells. Our results indicated that the in vitro three-dimensional (3D) model based on ALG beads increased metastatic ability compared with adhesion culture, even partly mimicked the in vivo tumor tissues. Moreover, due to the controllable preparation conditions, steady characteristics and production at large-scale, the 3D ALG bead model would become an important tool used in the high-throughput screening of anti-metastasis drugs and the metastatic mechanism research. -- Highlights: •We established a 3D metastasis model mimicking the metastatic ability in vivo. •The invasion ability of cells derived from our model was increased significantly. •The model is easy to reproduce, convenient to handle, and amenable for large-scale

  8. Xenobiotic metabolism capacities of human skin in comparison with a 3D-epidermis model and keratinocyte-based cell culture as in vitro alternatives for chemical testing: phase II enzymes.

    Science.gov (United States)

    Götz, Christine; Pfeiffer, Roland; Tigges, Julia; Ruwiedel, Karsten; Hübenthal, Ulrike; Merk, Hans F; Krutmann, Jean; Edwards, Robert J; Abel, Josef; Pease, Camilla; Goebel, Carsten; Hewitt, Nicola; Fritsche, Ellen

    2012-05-01

    The 7th Amendment to the EU Cosmetics Directive prohibits the use of animals in cosmetic testing for certain endpoints, such as genotoxicity. Therefore, skin in vitro models have to replace chemical testing in vivo. However, the metabolic competence neither of human skin nor of alternative in vitro models has so far been fully characterized, although skin is the first-pass organ for accidentally or purposely (cosmetics and pharmaceuticals) applied chemicals. Thus, there is an urgent need to understand the xenobiotic-metabolizing capacities of human skin and to compare these activities to models developed to replace animal testing. We have measured the activity of the phase II enzymes glutathione S-transferase, UDP-glucuronosyltransferase and N-acetyltransferase in ex vivo human skin, the 3D epidermal model EpiDerm 200 (EPI-200), immortalized keratinocyte-based cell lines (HaCaT and NCTC 2544) and primary normal human epidermal keratinocytes. We show that all three phase II enzymes are present and highly active in skin as compared to phase I. Human skin, therefore, represents a more detoxifying than activating organ. This work systematically compares the activities of three important phase II enzymes in four different in vitro models directly to human skin. We conclude from our studies that 3D epidermal models, like the EPI-200 employed here, are superior over monolayer cultures in mimicking human skin xenobiotic metabolism and thus better suited for dermatotoxicity testing. © 2012 John Wiley & Sons A/S.

  9. Human Cancer Models Initiative | Office of Cancer Genomics

    Science.gov (United States)

    The Human Cancer Models Initiative (HCMI) is an international consortium that is generating novel human tumor-derived culture models, which are annotated with genomic and clinical data. In an effort to advance cancer research and more fully understand how in vitro findings are related to clinical biology, HCMI-developed models and related data will be available as a community resource for cancer research.

  10. Synthetic vision and memory model for virtual human - biomed 2010.

    Science.gov (United States)

    Zhao, Yue; Kang, Jinsheng; Wright, David

    2010-01-01

    This paper describes the methods and case studies of a novel synthetic vision and memory model for virtual human. The synthetic vision module simulates the biological / optical abilities and limitations of the human vision. The module is based on a series of collision detection between the boundary of virtual humans field of vision (FOV) volume and the surface of objects in a recreated 3D environment. The memory module simulates a short-term memory capability by employing a simplified memory structure (first-in-first-out stack). The synthetic vision and memory model has been integrated into a virtual human modelling project, Intelligent Virtual Modelling. The project aimed to improve the realism and autonomy of virtual humans.

  11. How do humans inspect BPMN models: an exploratory study.

    Science.gov (United States)

    Haisjackl, Cornelia; Soffer, Pnina; Lim, Shao Yi; Weber, Barbara

    2018-01-01

    Even though considerable progress regarding the technical perspective on modeling and supporting business processes has been achieved, it appears that the human perspective is still often left aside. In particular, we do not have an in-depth understanding of how process models are inspected by humans, what strategies are taken, what challenges arise, and what cognitive processes are involved. This paper contributes toward such an understanding and reports an exploratory study investigating how humans identify and classify quality issues in BPMN process models. Providing preliminary answers to initial research questions, we also indicate other research questions that can be investigated using this approach. Our qualitative analysis shows that humans adapt different strategies on how to identify quality issues. In addition, we observed several challenges appearing when humans inspect process models. Finally, we present different manners in which classification of quality issues was addressed.

  12. Modelling human agency in ancient irrigation

    NARCIS (Netherlands)

    Ertsen, M.W.

    2011-01-01

    Human activity is key in understanding ancient irrigation systems. Results of short term actions build up over time, affecting civilizations on larger temporal and spatial scales. Irrigation systems, with their many entities, social and physical, their many interactions within a changing environment

  13. Pig models for the human heart failure syndrome

    DEFF Research Database (Denmark)

    Hunter, Ingrid; Terzic, Dijana; Zois, Nora Elisabeth

    2014-01-01

    Human heart failure remains a challenging illness despite advances in the diagnosis and treatment of heart failure patients. There is a need for further improvement of our understanding of the failing myocardium and its molecular deterioration. Porcine models provide an important research tool...... in this respect as molecular changes can be examined in detail, which is simply not feasible in human patients. However, the human heart failure syndrome is based on symptoms and signs, where pig models mostly mimic the myocardial damage, but without decisive data on clinical presentation and, therefore, a heart...... to elucidate the human heart failure syndrome....

  14. Human performance models for computer-aided engineering

    Science.gov (United States)

    Elkind, Jerome I. (Editor); Card, Stuart K. (Editor); Hochberg, Julian (Editor); Huey, Beverly Messick (Editor)

    1989-01-01

    This report discusses a topic important to the field of computational human factors: models of human performance and their use in computer-based engineering facilities for the design of complex systems. It focuses on a particular human factors design problem -- the design of cockpit systems for advanced helicopters -- and on a particular aspect of human performance -- vision and related cognitive functions. By focusing in this way, the authors were able to address the selected topics in some depth and develop findings and recommendations that they believe have application to many other aspects of human performance and to other design domains.

  15. A critique of recent models for human error rate assessment

    International Nuclear Information System (INIS)

    Apostolakis, G.E.

    1988-01-01

    This paper critically reviews two groups of models for assessing human error rates under accident conditions. The first group, which includes the US Nuclear Regulatory Commission (NRC) handbook model and the human cognitive reliability (HCR) model, considers as fundamental the time that is available to the operators to act. The second group, which is represented by the success likelihood index methodology multiattribute utility decomposition (SLIM-MAUD) model, relies on ratings of the human actions with respect to certain qualitative factors and the subsequent derivation of error rates. These models are evaluated with respect to two criteria: the treatment of uncertainties and the internal coherence of the models. In other words, this evaluation focuses primarily on normative aspects of these models. The principal findings are as follows: (1) Both of the time-related models provide human error rates as a function of the available time for action and the prevailing conditions. However, the HCR model ignores the important issue of state-of-knowledge uncertainties, dealing exclusively with stochastic uncertainty, whereas the model presented in the NRC handbook handles both types of uncertainty. (2) SLIM-MAUD provides a highly structured approach for the derivation of human error rates under given conditions. However, the treatment of the weights and ratings in this model is internally inconsistent. (author)

  16. Human tissue models in cancer research: looking beyond the mouse

    Directory of Open Access Journals (Sweden)

    Samuel J. Jackson

    2017-08-01

    Full Text Available Mouse models, including patient-derived xenograft mice, are widely used to address questions in cancer research. However, there are documented flaws in these models that can result in the misrepresentation of human tumour biology and limit the suitability of the model for translational research. A coordinated effort to promote the more widespread development and use of ‘non-animal human tissue’ models could provide a clinically relevant platform for many cancer studies, maximising the opportunities presented by human tissue resources such as biobanks. A number of key factors limit the wide adoption of non-animal human tissue models in cancer research, including deficiencies in the infrastructure and the technical tools required to collect, transport, store and maintain human tissue for lab use. Another obstacle is the long-standing cultural reliance on animal models, which can make researchers resistant to change, often because of concerns about historical data compatibility and losing ground in a competitive environment while new approaches are embedded in lab practice. There are a wide range of initiatives that aim to address these issues by facilitating data sharing and promoting collaborations between organisations and researchers who work with human tissue. The importance of coordinating biobanks and introducing quality standards is gaining momentum. There is an exciting opportunity to transform cancer drug discovery by optimising the use of human tissue and reducing the reliance on potentially less predictive animal models.

  17. Human tissue models in cancer research: looking beyond the mouse.

    Science.gov (United States)

    Jackson, Samuel J; Thomas, Gareth J

    2017-08-01

    Mouse models, including patient-derived xenograft mice, are widely used to address questions in cancer research. However, there are documented flaws in these models that can result in the misrepresentation of human tumour biology and limit the suitability of the model for translational research. A coordinated effort to promote the more widespread development and use of 'non-animal human tissue' models could provide a clinically relevant platform for many cancer studies, maximising the opportunities presented by human tissue resources such as biobanks. A number of key factors limit the wide adoption of non-animal human tissue models in cancer research, including deficiencies in the infrastructure and the technical tools required to collect, transport, store and maintain human tissue for lab use. Another obstacle is the long-standing cultural reliance on animal models, which can make researchers resistant to change, often because of concerns about historical data compatibility and losing ground in a competitive environment while new approaches are embedded in lab practice. There are a wide range of initiatives that aim to address these issues by facilitating data sharing and promoting collaborations between organisations and researchers who work with human tissue. The importance of coordinating biobanks and introducing quality standards is gaining momentum. There is an exciting opportunity to transform cancer drug discovery by optimising the use of human tissue and reducing the reliance on potentially less predictive animal models. © 2017. Published by The Company of Biologists Ltd.

  18. Kernel Method Based Human Model for Enhancing Interactive Evolutionary Optimization

    Science.gov (United States)

    Zhao, Qiangfu; Liu, Yong

    2015-01-01

    A fitness landscape presents the relationship between individual and its reproductive success in evolutionary computation (EC). However, discrete and approximate landscape in an original search space may not support enough and accurate information for EC search, especially in interactive EC (IEC). The fitness landscape of human subjective evaluation in IEC is very difficult and impossible to model, even with a hypothesis of what its definition might be. In this paper, we propose a method to establish a human model in projected high dimensional search space by kernel classification for enhancing IEC search. Because bivalent logic is a simplest perceptual paradigm, the human model is established by considering this paradigm principle. In feature space, we design a linear classifier as a human model to obtain user preference knowledge, which cannot be supported linearly in original discrete search space. The human model is established by this method for predicting potential perceptual knowledge of human. With the human model, we design an evolution control method to enhance IEC search. From experimental evaluation results with a pseudo-IEC user, our proposed model and method can enhance IEC search significantly. PMID:25879050

  19. Drosophila Melanogaster as an Emerging Translational Model of Human Nephrolithiasis

    Science.gov (United States)

    Miller, Joe; Chi, Thomas; Kapahi, Pankaj; Kahn, Arnold J.; Kim, Man Su; Hirata, Taku; Romero, Michael F.; Dow, Julian A.T.; Stoller, Marshall L.

    2013-01-01

    Purpose The limitations imposed by human clinical studies and mammalian models of nephrolithiasis have hampered the development of effective medical treatments and preventative measures for decades. The simple but elegant Drosophila melanogaster is emerging as a powerful translational model of human disease, including nephrolithiasis and may provide important information essential to our understanding of stone formation. We present the current state of research using D. melanogaster as a model of human nephrolithiasis. Materials and Methods A comprehensive review of the English language literature was performed using PUBMED. When necessary, authoritative texts on relevant subtopics were consulted. Results The genetic composition, anatomic structure and physiologic function of Drosophila Malpighian tubules are remarkably similar to those of the human nephron. The direct effects of dietary manipulation, environmental alteration, and genetic variation on stone formation can be observed and quantified in a matter of days. Several Drosophila models of human nephrolithiasis, including genetically linked and environmentally induced stones, have been developed. A model of calcium oxalate stone formation is among the most recent fly models of human nephrolithiasis. Conclusions The ability to readily manipulate and quantify stone formation in D. melanogaster models of human nephrolithiasis presents the urologic community with a unique opportunity to increase our understanding of this enigmatic disease. PMID:23500641

  20. Human Digital Modeling & Hand Scanning Lab

    Data.gov (United States)

    Federal Laboratory Consortium — This laboratory incorporates specialized scanning equipment, computer workstations and software applications for the acquisition and analysis of digitized models of...

  1. A surgical ankle sprain pain model in the rat: Effects of morphine and indomethacin

    OpenAIRE

    Young Kim, Hee; Wang, Jigong; Chung, Kyungsoon; Mo Chung, Jin

    2008-01-01

    Ankle sprain is a frequent injury in humans that results in pain, swelling and difficulty in walking on the affected ankle. Currently a suitable animal model resembling human ankle sprain is lacking. Here, we describe an animal ankle sprain model induced by ankle ligament injury (ALI) in rats. Cutting combinations of the lateral ankle ligament complex produced pain, edema and difficulty of weight bearing, thereby mimicking severe (grade III) ankle sprain in humans. Analgesic compounds, morphi...

  2. Mechanical Impedance Modeling of Human Arm: A survey

    Science.gov (United States)

    Puzi, A. Ahmad; Sidek, S. N.; Sado, F.

    2017-03-01

    Human arm mechanical impedance plays a vital role in describing motion ability of the upper limb. One of the impedance parameters is stiffness which is defined as the ratio of an applied force to the measured deformation of the muscle. The arm mechanical impedance modeling is useful in order to develop a better controller for system that interacts with human as such an automated robot-assisted platform for automated rehabilitation training. The aim of the survey is to summarize the existing mechanical impedance models of human upper limb so to justify the need to have an improved version of the arm model in order to facilitate the development of better controller of such systems with ever increase in complexity. In particular, the paper will address the following issue: Human motor control and motor learning, constant and variable impedance models, methods for measuring mechanical impedance and mechanical impedance modeling techniques.

  3. A Perspective on Computational Human Performance Models as Design Tools

    Science.gov (United States)

    Jones, Patricia M.

    2010-01-01

    The design of interactive systems, including levels of automation, displays, and controls, is usually based on design guidelines and iterative empirical prototyping. A complementary approach is to use computational human performance models to evaluate designs. An integrated strategy of model-based and empirical test and evaluation activities is particularly attractive as a methodology for verification and validation of human-rated systems for commercial space. This talk will review several computational human performance modeling approaches and their applicability to design of display and control requirements.

  4. Human Spaceflight Architecture Model (HSFAM) Data Dictionary

    Science.gov (United States)

    Shishko, Robert

    2016-01-01

    HSFAM is a data model based on the DoDAF 2.02 data model with some for purpose extensions. These extensions are designed to permit quantitative analyses regarding stakeholder concerns about technical feasibility, configuration and interface issues, and budgetary and/or economic viability.

  5. Human performance modeling for system of systems analytics.

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, Kevin R.; Lawton, Craig R.; Basilico, Justin Derrick; Longsine, Dennis E. (INTERA, Inc., Austin, TX); Forsythe, James Chris; Gauthier, John Henry; Le, Hai D.

    2008-10-01

    A Laboratory-Directed Research and Development project was initiated in 2005 to investigate Human Performance Modeling in a System of Systems analytic environment. SAND2006-6569 and SAND2006-7911 document interim results from this effort; this report documents the final results. The problem is difficult because of the number of humans involved in a System of Systems environment and the generally poorly defined nature of the tasks that each human must perform. A two-pronged strategy was followed: one prong was to develop human models using a probability-based method similar to that first developed for relatively well-understood probability based performance modeling; another prong was to investigate more state-of-art human cognition models. The probability-based modeling resulted in a comprehensive addition of human-modeling capability to the existing SoSAT computer program. The cognitive modeling resulted in an increased understanding of what is necessary to incorporate cognition-based models to a System of Systems analytic environment.

  6. Chronic multifocal non-bacterial osteomyelitis in hypophosphatasia mimicking malignancy

    Directory of Open Access Journals (Sweden)

    Warmuth-Metz Monika

    2007-01-01

    Full Text Available Abstract Background Hypophosphatasia (HP is characterized by a genetic defect in the tissue-nonspecific alkaline phosphatase (TNSALP gene and predominantly an autosomal recessive trait. HP patients suffer from reduced bone mineralization. Biochemically, elevated concentrations of substrates of TNSALP, including pyridoxal-5'-phosphate and inorganic pyrophosphate occur in serum, tissues and urine. The latter has been associated with chronic inflammation and hyperprostaglandinism. Case presentation We report on 2 affected children presenting with multifocal inflammatory bone lesions mimicking malignancy: A 6 years old girl with short stature had been treated with human growth hormone since 6 months. Then she started to complain about a painful swelling of her left cheek. MRI suggested a malignant bone lesion. Bone biopsy, however, revealed chronic inflammation. A bone scan showed a second rib lesion. Since biopsy was sterile, the descriptive diagnosis of chronic non-bacterial osteomyelitis (CNO was established. The diagnostic tests related to growth failure were repeated and subsequent analyses demonstrated a molecular defect in the TNSALP gene. The second girl (10 years old complained about back pain after she had fallen from her bike. X rays of her spine revealed compressions of 2 thoracic vertebrae. At first these were considered trauma related, however a bone scan did show an additional lesion in the right 4th rib. A biopsy of this rib revealed a sterile lympho- plasmocytoid osteomyelitis suggesting multifocal CNO. Further analyses did show a decreased TNSALP in leukocytes and elevated pyridoxal phosphate in plasma, suggesting a heterozygous carrier status of HP. Conclusion Chronic bone oedema in adult HP and chronic hyper-prostaglandinism in childhood HP do suggest that in some HP patients bone inflammation is present in conjunction with the metabolic defect. Sterile multifocal osteomyelitis could be demonstrated. Non-steroidal anti

  7. Human reconstructed skin xenografts on mice to model skin physiology.

    Science.gov (United States)

    Salgado, Giorgiana; Ng, Yi Zhen; Koh, Li Fang; Goh, Christabelle S M; Common, John E

    Xenograft models to study skin physiology have been popular for scientific use since the 1970s, with various developments and improvements to the techniques over the decades. Xenograft models are particularly useful and sought after due to the lack of clinically relevant animal models in predicting drug effectiveness in humans. Such predictions could in turn boost the process of drug discovery, since novel drug compounds have an estimated 8% chance of FDA approval despite years of rigorous preclinical testing and evaluation, albeit mostly in non-human models. In the case of skin research, the mouse persists as the most popular animal model of choice, despite its well-known anatomical differences with human skin. Differences in skin biology are especially evident when trying to dissect more complex skin conditions, such as psoriasis and eczema, where interactions between the immune system, epidermis and the environment likely occur. While the use of animal models are still considered the gold standard for systemic toxicity studies under controlled environments, there are now alternative models that have been approved for certain applications. To overcome the biological limitations of the mouse model, research efforts have also focused on "humanizing" the mice model to better recapitulate human skin physiology. In this review, we outline the different approaches undertaken thus far to study skin biology using human tissue xenografts in mice and the technical challenges involved. We also describe more recent developments to generate humanized multi-tissue compartment mice that carry both a functioning human immune system and skin xenografts. Such composite animal models provide promising opportunities to study drugs, disease and differentiation with greater clinical relevance. Copyright © 2017 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  8. Some aspects of statistical modeling of human-error probability

    International Nuclear Information System (INIS)

    Prairie, R.R.

    1982-01-01

    Human reliability analyses (HRA) are often performed as part of risk assessment and reliability projects. Recent events in nuclear power have shown the potential importance of the human element. There are several on-going efforts in the US and elsewhere with the purpose of modeling human error such that the human contribution can be incorporated into an overall risk assessment associated with one or more aspects of nuclear power. An effort that is described here uses the HRA (event tree) to quantify and model the human contribution to risk. As an example, risk analyses are being prepared on several nuclear power plants as part of the Interim Reliability Assessment Program (IREP). In this process the risk analyst selects the elements of his fault tree that could be contributed to by human error. He then solicits the HF analyst to do a HRA on this element

  9. How do humans inspect BPMN models: an exploratory study

    DEFF Research Database (Denmark)

    Haisjackl, Cornelia; Soffer, Pnina; Lim, Shao Yi

    2016-01-01

    to initial research questions, we also indicate other research questions that can be investigated using this approach. Our qualitative analysis shows that humans adapt different strategies on how to identify quality issues. In addition, we observed several challenges appearing when humans inspect process......Even though considerable progress regarding the technical perspective on modeling and supporting business processes has been achieved, it appears that the human perspective is still often left aside. In particular, we do not have an in-depth understanding of how process models are inspected...... by humans, what strategies are taken, what challenges arise, and what cognitive processes are involved. This paper contributes toward such an understanding and reports an exploratory study investigating how humans identify and classify quality issues in BPMN process models. Providing preliminary answers...

  10. Vaccines against viral hemorrhagic fevers: non-human primate models.

    Science.gov (United States)

    Carrion, Ricardo; Patterson, Jean L

    2011-06-01

    Viral hemorrhagic fevers are a group of disease syndromes caused by infection with certain RNA viruses. The disease is marked by a febrile response, malaise, coagulopathy and vascular permeability culminating in death. Case fatality rates can reach 90% depending on the etiologic agent. Currently, there is no approved antiviral treatment. Because of the high case fatality, risk of importation and the potential to use these agents as biological weapons, development of countermeasures to these agents is a high priority. The sporadic nature of disease outbreaks and the ethical issues associated with conducting a human trial for such diseases make human studies impractical; therefore, development of countermeasures must occur in relevant animal models. Non-human primates are superior models to study infectious disease because their immune system is similar to humans and they are good predictors of efficacy in vaccine development and other intervention strategies. This review article summarizes viral hemorrhagic fever non-human primate models.

  11. In vivo human corneal hydration control dynamics: A new model

    NARCIS (Netherlands)

    Odenthal, M.T.P.; Nieuwendaal, C.P.; Venema, H.W.; Oosting, J.; Kok, J.H.C.; Kijlstra, A.

    1999-01-01

    PURPOSE. To introduce a new model describing human in vivo corneal deswelling after hypoxic contact lens wear, based on a damped harmonic oscillator, which can describe an overshoot in corneal deswelling, to compare this new model with the currently used exponential model, and also to test whether a

  12. In vivo human corneal hydration control dynamics: a new model

    NARCIS (Netherlands)

    Odenthal, M. T.; Nieuwendaal, C. P.; Venema, H. W.; Oosting, J.; Kok, J. H. C.; Kijlstra, A.

    1999-01-01

    PURPOSE: To introduce a new model describing human in vivo corneal deswelling after hypoxic contact lens wear, based on a damped harmonic oscillator, which can describe an overshoot in corneal deswelling, to compare this new model with the currently used exponential model, and also to test whether a

  13. Human Engineering Modeling and Performance Lab Study Project

    Science.gov (United States)

    Oliva-Buisson, Yvette J.

    2014-01-01

    The HEMAP (Human Engineering Modeling and Performance) Lab is a joint effort between the Industrial and Human Engineering group and the KAVE (Kennedy Advanced Visualiations Environment) group. The lab consists of sixteen camera system that is used to capture human motions and operational tasks, through te use of a Velcro suit equipped with sensors, and then simulate these tasks in an ergonomic software package know as Jac, The Jack software is able to identify the potential risk hazards.

  14. Model-Based approaches to Human-Automation Systems Design

    DEFF Research Database (Denmark)

    Jamieson, Greg A.; Andersson, Jonas; Bisantz, Ann

    2012-01-01

    Human-automation interaction in complex systems is common, yet design for this interaction is often conducted without explicit consideration of the role of the human operator. Fortunately, there are a number of modeling frameworks proposed for supporting this design activity. However...... (and reportedly one or two critics) can engage one another on several agreed questions about such frameworks. The goal is to aid non-aligned practitioners in choosing between alternative frameworks for their human-automation interaction design challenges....

  15. Computational Models of Human Organizational Dynamics

    National Research Council Canada - National Science Library

    Courand, Gregg

    2000-01-01

    .... ThIs is the final report for our Phase II SBIR project, conducted over three years. Our research program has contributed theory, methodology, and technology for organizational modeling and analysis...

  16. A Review on Human Respiratory Modeling.

    Science.gov (United States)

    Ghafarian, Pardis; Jamaati, Hamidreza; Hashemian, Seyed Mohammadreza

    2016-01-01

    Input impedance of the respiratory system is measured by forced oscillation technique (FOT). Multiple prior studies have attempted to match the electromechanical models of the respiratory system to impedance data. Since the mechanical behavior of airways and the respiratory system as a whole are similar to an electrical circuit in a combination of series and parallel formats some theories were introduced according to this issue. It should be noted that, the number of elements used in these models might be less than those required due to the complexity of the pulmonary-chest wall anatomy. Various respiratory models have been proposed based on this idea in order to demonstrate and assess the different parts of respiratory system related to children and adults data. With regard to our knowledge, some of famous respiratory models in related to obstructive, restrictive diseases and also Acute Respiratory Distress Syndrome (ARDS) are reviewed in this article.

  17. Biomechanical Modeling of the Human Head

    Science.gov (United States)

    2017-10-03

    Naval Research Laboratory Washington, DC 20375-5320 DISTRIBUTION STATEMENT A: Approved for public release; distribution is unlimited. October 3...Laboratory 4555 Overlook Avenue, SW Washington, DC 20375-5320 NRL/FR/6350--17-10,304 DISTRIBUTION STATEMENT A: Approved for public release; distribution is... generating a calibrated constitutive model. First, a constitutive model form that can sufficiently capture the phenomena that occur in the experimental data is

  18. Mathematical modeling of human thermoregulation : a neurophysiological approach to vasoconstriction

    NARCIS (Netherlands)

    Kingma, B.R.M.; Frijns, A.J.H.; Saris, W.H.; Steenhoven, van A.A.; Marken Lichtenbelt, van W.D.; Madani, K.; Correia, A.D.; Rosa, A.; Filipe, J.

    2012-01-01

    Skin blood flow is of major importance in human thermoregulation. Classic thermoregulation models require an explicit set point to control temperature. Normally such a set point is defined in the unit of the controlled variable (i.e. Celsius). However, the human body does not sense temperature

  19. Heterogeneous Community-based mobility model for human opportunistic network

    DEFF Research Database (Denmark)

    Hu, Liang; Dittmann, Lars

    2009-01-01

    a heterogeneous community-based random way-point (HC-RWP) mobility model that captures the four important properties of real human mobility. These properties are based on both intuitive observations of daily human mobility and analysis of empirical mobility traces. By discrete event simulation, we show HC...

  20. DEVELOPMENT OF 2D HUMAN BODY MODELING USING THINNING ALGORITHM

    Directory of Open Access Journals (Sweden)

    K. Srinivasan

    2010-11-01

    Full Text Available Monitoring the behavior and activities of people in Video surveillance has gained more applications in Computer vision. This paper proposes a new approach to model the human body in 2D view for the activity analysis using Thinning algorithm. The first step of this work is Background subtraction which is achieved by the frame differencing algorithm. Thinning algorithm has been used to find the skeleton of the human body. After thinning, the thirteen feature points like terminating points, intersecting points, shoulder, elbow, and knee points have been extracted. Here, this research work attempts to represent the body model in three different ways such as Stick figure model, Patch model and Rectangle body model. The activities of humans have been analyzed with the help of 2D model for the pre-defined poses from the monocular video data. Finally, the time consumption and efficiency of our proposed algorithm have been evaluated.

  1. Dynamic Human Body Modeling Using a Single RGB Camera.

    Science.gov (United States)

    Zhu, Haiyu; Yu, Yao; Zhou, Yu; Du, Sidan

    2016-03-18

    In this paper, we present a novel automatic pipeline to build personalized parametric models of dynamic people using a single RGB camera. Compared to previous approaches that use monocular RGB images, our system can model a 3D human body automatically and incrementally, taking advantage of human motion. Based on coarse 2D and 3D poses estimated from image sequences, we first perform a kinematic classification of human body parts to refine the poses and obtain reconstructed body parts. Next, a personalized parametric human model is generated by driving a general template to fit the body parts and calculating the non-rigid deformation. Experimental results show that our shape estimation method achieves comparable accuracy with reconstructed models using depth cameras, yet requires neither user interaction nor any dedicated devices, leading to the feasibility of using this method on widely available smart phones.

  2. Computational Modeling of Human Multiple-Task Performance

    National Research Council Canada - National Science Library

    Kieras, David E; Meyer, David

    2005-01-01

    This is the final report for a project that was a continuation of an earlier, long-term project on the development and validation of the EPIC cognitive architecture for modeling human cognition and performance...

  3. Modelling human behaviours and reactions under dangerous environment

    OpenAIRE

    Kang, J; Wright, D K; Qin, S F; Zhao, Y

    2005-01-01

    This paper describes the framework of a real-time simulation system to model human behavior and reactions in dangerous environments. The system utilizes the latest 3D computer animation techniques, combined with artificial intelligence, robotics and psychology, to model human behavior, reactions and decision making under expected/unexpected dangers in real-time in virtual environments. The development of the system includes: classification on the conscious/subconscious behaviors and reactions...

  4. Application of postured human model for SAR measurements

    Science.gov (United States)

    Vuchkovikj, M.; Munteanu, I.; Weiland, T.

    2013-07-01

    In the last two decades, the increasing number of electronic devices used in day-to-day life led to a growing interest in the study of the electromagnetic field interaction with biological tissues. The design of medical devices and wireless communication devices such as mobile phones benefits a lot from the bio-electromagnetic simulations in which digital human models are used. The digital human models currently available have an upright position which limits the research activities in realistic scenarios, where postured human bodies must be considered. For this reason, a software application called "BodyFlex for CST STUDIO SUITE" was developed. In its current version, this application can deform the voxel-based human model named HUGO (Dipp GmbH, 2010) to allow the generation of common postures that people use in normal life, ensuring the continuity of tissues and conserving the mass to an acceptable level. This paper describes the enhancement of the "BodyFlex" application, which is related to the movements of the forearm and the wrist of a digital human model. One of the electromagnetic applications in which the forearm and the wrist movement of a voxel based human model has a significant meaning is the measurement of the specific absorption rate (SAR) when a model is exposed to a radio frequency electromagnetic field produced by a mobile phone. Current SAR measurements of the exposure from mobile phones are performed with the SAM (Specific Anthropomorphic Mannequin) phantom which is filled with a dispersive but homogeneous material. We are interested what happens with the SAR values if a realistic inhomogeneous human model is used. To this aim, two human models, a homogeneous and an inhomogeneous one, in two simulation scenarios are used, in order to examine and observe the differences in the results for the SAR values.

  5. Process modeling for Humanities: tracing and analyzing scientific processes

    OpenAIRE

    Hug , Charlotte; Salinesi , Camille; Deneckere , Rebecca; Lamasse , Stéphane

    2011-01-01

    International audience; This paper concerns epistemology and the understanding of research processes in Humanities, such as Archaeology. We believe that to properly understand research processes, it is essential to trace them. The collected traces depend on the process model established, which has to be as accurate as possible to exhaustively record the traces. In this paper, we briefly explain why the existing process models for Humanities are not sufficient to represent traces. We then pres...

  6. Human eyeball model reconstruction and quantitative analysis.

    Science.gov (United States)

    Xing, Qi; Wei, Qi

    2014-01-01

    Determining shape of the eyeball is important to diagnose eyeball disease like myopia. In this paper, we present an automatic approach to precisely reconstruct three dimensional geometric shape of eyeball from MR Images. The model development pipeline involved image segmentation, registration, B-Spline surface fitting and subdivision surface fitting, neither of which required manual interaction. From the high resolution resultant models, geometric characteristics of the eyeball can be accurately quantified and analyzed. In addition to the eight metrics commonly used by existing studies, we proposed two novel metrics, Gaussian Curvature Analysis and Sphere Distance Deviation, to quantify the cornea shape and the whole eyeball surface respectively. The experiment results showed that the reconstructed eyeball models accurately represent the complex morphology of the eye. The ten metrics parameterize the eyeball among different subjects, which can potentially be used for eye disease diagnosis.

  7. Human casualties in earthquakes: Modelling and mitigation

    Science.gov (United States)

    Spence, R.J.S.; So, E.K.M.

    2011-01-01

    Earthquake risk modelling is needed for the planning of post-event emergency operations, for the development of insurance schemes, for the planning of mitigation measures in the existing building stock, and for the development of appropriate building regulations; in all of these applications estimates of casualty numbers are essential. But there are many questions about casualty estimation which are still poorly understood. These questions relate to the causes and nature of the injuries and deaths, and the extent to which they can be quantified. This paper looks at the evidence on these questions from recent studies. It then reviews casualty estimation models available, and finally compares the performance of some casualty models in making rapid post-event casualty estimates in recent earthquakes.

  8. Mimicked cartilage scaffolds of silk fibroin/hyaluronic acid with stem cells for osteoarthritis surgery: Morphological, mechanical, and physical clues

    International Nuclear Information System (INIS)

    Jaipaew, Jirayut; Wangkulangkul, Piyanun; Meesane, Jirut; Raungrut, Pritsana; Puttawibul, Puttisak

    2016-01-01

    Osteoarthritis is a critical disease that comes from degeneration of cartilage tissue. In severe cases surgery is generally required. Tissue engineering using scaffolds with stem cell transplantation is an attractive approach and a challenge for orthopedic surgery. For sample preparation, silk fibroin (SF)/hyaluronic acid (HA) scaffolds in different ratios of SF/HA (w/w) (i.e., 100:0, 90:10, 80:20, and 70:30) were formed by freeze-drying. The morphological, mechanical, and physical clues were considered in this research. The morphological structure of the scaffolds was observed by scanning electron microscope. The mechanical and physical properties of the scaffolds were analyzed by compressive and swelling ratio testing, respectively. For the cell experiments, scaffolds were seeded and cultured with human umbilical cord-derived mesenchymal stem cells (HUMSCs). The cultured scaffolds were tested for cell viability, histochemistry, immunohistochemistry, and gene expression. The SF with HA scaffolds showed regular porous structures. Those scaffolds had a soft and elastic characteristic with a high swelling ratio and water uptake. The SF/HA scaffolds showed a spheroid structure of the cells in the porous structure particularly in the SF80 and SF70 scaffolds. Cells could express Col2a, Agg, and Sox9 which are markers for chondrogenesis. It could be deduced that SF/HA scaffolds showed significant clues for suitability in cartilage tissue engineering and in surgery for osteoarthritis. - Highlights: • Silk fibroin/Hyaluronic acid was fabricated into mimicked scaffolds. • Mimicked scaffolds were incorporated with stem cells for chondrogenesis. • Mimicked scaffolds showed the clues for chondrogenic regulation. • Mimicked scaffolds had suitable performance for cartilage tissue engineering • Mimicked scaffolds showed promise for osteoarthritis surgery.

  9. Heparin-mimicking multilayer coating on polymeric membrane via LbL assembly of cyclodextrin-based supramolecules.

    Science.gov (United States)

    Deng, Jie; Liu, Xinyue; Ma, Lang; Cheng, Chong; Shi, Wenbin; Nie, Chuanxiong; Zhao, Changsheng

    2014-12-10

    In this study, multifunctional and heparin-mimicking star-shaped supramolecules-deposited 3D porous multilayer films with improved biocompatibility were fabricated via a layer-by-layer (LbL) self-assembly method on polymeric membrane substrates. Star-shaped heparin-mimicking polyanions (including poly(styrenesulfonate-co-sodium acrylate; Star-PSS-AANa) and poly(styrenesulfonate-co-poly(ethylene glycol)methyl ether methacrylate; Star-PSS-EGMA)) and polycations (poly(methyl chloride-quaternized 2-(dimethylamino)ethyl methacrylate; Star-PMeDMA) were first synthesized by atom transfer radical polymerization (ATRP) from β-cyclodextrin (β-CD) based cores. Then assembly of 3D porous multilayers onto polymeric membrane surfaces was carried out by alternating deposition of the polyanions and polycations via electrostatic interaction. The surface morphology and composition, water contact angle, blood activation, and thrombotic potential as well as cell viability for the coated heparin-mimicking films were systematically investigated. The results of surface ATR-FTIR spectra and XPS spectra verified successful deposition of the star-shaped supramolecules onto the biomedical membrane surfaces; scanning electron microscopy (SEM) and atomic force microscopy (AFM) observations revealed that the modified substrate had 3D porous surface morphology, which might have a great biological influence on the biointerface. Furthermore, systematic in vitro investigation of protein adsorption, platelet adhesion, human platelet factor 4 (PF4, indicates platelet activation), activate partial thromboplastin time (APTT), thrombin time (TT), coagulation activation (thrombin-antithrombin III complex (TAT, indicates blood coagulant)), and blood-related complement activation (C3a and C5a, indicates inflammation potential) confirmed that the heparin-mimicking multilayer coated membranes exhibited ultralow blood component activations and excellent hemocompatibility. Meanwhile, after surface coating

  10. Mimicked cartilage scaffolds of silk fibroin/hyaluronic acid with stem cells for osteoarthritis surgery: Morphological, mechanical, and physical clues

    Energy Technology Data Exchange (ETDEWEB)

    Jaipaew, Jirayut [Institute of Biomedical Engineering, Faculty of Medicine, Prince of Songkla University, 15 Karnjanavanich Road, Hat Yai, Songkhla, Thailand 90110 (Thailand); Wangkulangkul, Piyanun [Institute of Biomedical Engineering, Faculty of Medicine, Prince of Songkla University, 15 Karnjanavanich Road, Hat Yai, Songkhla, Thailand 90110 (Thailand); Department of Surgery, Faculty of Medicine, Prince of Songkla University, 15 Karnjanavanich Road, Hat Yai, Songkhla, Thailand 90110 (Thailand); Meesane, Jirut, E-mail: jirutmeesane999@yahoo.co.uk [Institute of Biomedical Engineering, Faculty of Medicine, Prince of Songkla University, 15 Karnjanavanich Road, Hat Yai, Songkhla, Thailand 90110 (Thailand); Raungrut, Pritsana [Department of Biomedical Science, Faculty of Medicine, Prince of Songkla University, 15 Karnjanavanich Road, Hat Yai, Songkhla, Thailand 90110 (Thailand); Puttawibul, Puttisak [Institute of Biomedical Engineering, Faculty of Medicine, Prince of Songkla University, 15 Karnjanavanich Road, Hat Yai, Songkhla, Thailand 90110 (Thailand); Department of Surgery, Faculty of Medicine, Prince of Songkla University, 15 Karnjanavanich Road, Hat Yai, Songkhla, Thailand 90110 (Thailand)

    2016-07-01

    Osteoarthritis is a critical disease that comes from degeneration of cartilage tissue. In severe cases surgery is generally required. Tissue engineering using scaffolds with stem cell transplantation is an attractive approach and a challenge for orthopedic surgery. For sample preparation, silk fibroin (SF)/hyaluronic acid (HA) scaffolds in different ratios of SF/HA (w/w) (i.e., 100:0, 90:10, 80:20, and 70:30) were formed by freeze-drying. The morphological, mechanical, and physical clues were considered in this research. The morphological structure of the scaffolds was observed by scanning electron microscope. The mechanical and physical properties of the scaffolds were analyzed by compressive and swelling ratio testing, respectively. For the cell experiments, scaffolds were seeded and cultured with human umbilical cord-derived mesenchymal stem cells (HUMSCs). The cultured scaffolds were tested for cell viability, histochemistry, immunohistochemistry, and gene expression. The SF with HA scaffolds showed regular porous structures. Those scaffolds had a soft and elastic characteristic with a high swelling ratio and water uptake. The SF/HA scaffolds showed a spheroid structure of the cells in the porous structure particularly in the SF80 and SF70 scaffolds. Cells could express Col2a, Agg, and Sox9 which are markers for chondrogenesis. It could be deduced that SF/HA scaffolds showed significant clues for suitability in cartilage tissue engineering and in surgery for osteoarthritis. - Highlights: • Silk fibroin/Hyaluronic acid was fabricated into mimicked scaffolds. • Mimicked scaffolds were incorporated with stem cells for chondrogenesis. • Mimicked scaffolds showed the clues for chondrogenic regulation. • Mimicked scaffolds had suitable performance for cartilage tissue engineering • Mimicked scaffolds showed promise for osteoarthritis surgery.

  11. Plant Modeling for Human Supervisory Control

    DEFF Research Database (Denmark)

    Lind, Morten

    1999-01-01

    This paper provides an overview of multilevel flow modelling (MFM) and its application for design of displays for the supervisory control of industrial plant. The problem of designing the inforrrzatian content of sacpervisory displays is discussed and plant representations like MFM using levels...

  12. Modeling Human Aesthetic Perception of Visual Textures

    NARCIS (Netherlands)

    Thumfart, Stefan; Jacobs, Richard H. A. H.; Lughofer, Edwin; Eitzinger, Christian; Cornelissen, Frans W.; Groissboeck, Werner; Richter, Roland

    Texture is extensively used in areas such as product design and architecture to convey specific aesthetic information. Using the results of a psychological experiment, we model the relationship between computational texture features and aesthetic properties of visual textures. Contrary to previous

  13. Animal model of human disease. Multiple myeloma

    NARCIS (Netherlands)

    Radl, J.; Croese, J.W.; Zurcher, C.; Enden-Vieveen, M.H.M. van den; Leeuw, A.M. de

    1988-01-01

    Animal models of spontaneous and induced plasmacytomas in some inbred strains of mice have proven to be useful tools for different studies on tumorigenesis and immunoregulation. Their wide applicability and the fact that after their intravenous transplantation, the recipient mice developed bone

  14. Modeling human behaviors and reactions under dangerous environment.

    Science.gov (United States)

    Kang, J; Wright, D K; Qin, S F; Zhao, Y

    2005-01-01

    This paper describes the framework of a real-time simulation system to model human behavior and reactions in dangerous environments. The system utilizes the latest 3D computer animation techniques, combined with artificial intelligence, robotics and psychology, to model human behavior, reactions and decision making under expected/unexpected dangers in real-time in virtual environments. The development of the system includes: classification on the conscious/subconscious behaviors and reactions of different people; capturing different motion postures by the Eagle Digital System; establishing 3D character animation models; establishing 3D models for the scene; planning the scenario and the contents; and programming within Virtools Dev. Programming within Virtools Dev is subdivided into modeling dangerous events, modeling character's perceptions, modeling character's decision making, modeling character's movements, modeling character's interaction with environment and setting up the virtual cameras. The real-time simulation of human reactions in hazardous environments is invaluable in military defense, fire escape, rescue operation planning, traffic safety studies, and safety planning in chemical factories, the design of buildings, airplanes, ships and trains. Currently, human motion modeling can be realized through established technology, whereas to integrate perception and intelligence into virtual human's motion is still a huge undertaking. The challenges here are the synchronization of motion and intelligence, the accurate modeling of human's vision, smell, touch and hearing, the diversity and effects of emotion and personality in decision making. There are three types of software platforms which could be employed to realize the motion and intelligence within one system, and their advantages and disadvantages are discussed.

  15. 3D printed phantoms mimicking cortical bone for the assessment of ultrashort echo time magnetic resonance imaging.

    Science.gov (United States)

    Rai, Robba; Manton, David; Jameson, Michael G; Josan, Sonal; Barton, Michael B; Holloway, Lois C; Liney, Gary P

    2018-02-01

    Human cortical bone has a rapid T2∗ decay, and it can be visualized using ultrashort echo time (UTE) techniques in magnetic resonance imaging (MRI). These sequences operate at the limits of gradient and transmit-receive signal performance. Development of multicompartment anthropomorphic phantoms that can mimic human cortical bone can assist with quality assurance and optimization of UTE sequences. The aims of this study were to (a) characterize the MRI signal properties of a photopolymer resin that can be 3D printed, (b) develop multicompartment phantoms based on the resin, and (c) demonstrate the feasibility of using these phantoms to mimic human anatomy in the assessment of UTE sequences. A photopolymer resin (Prismlab China Ltd, Shanghai, China) was imaged on a 3 Tesla MRI system (Siemens Skyra) to characterize its MRI properties with emphasis on T2∗ signal and longevity. Two anthropomorphic phantoms, using the 3D printed resin to simulate skeletal anatomy, were developed and imaged using UTE sequences. A skull phantom was developed and used to assess the feasibility of using the resin to develop a complex model with realistic morphological human characteristics. A tibia model was also developed to assess the suitability of the resin at mimicking a simple multicompartment anatomical model and imaged using a three-dimensional UTE sequence (PETRA). Image quality measurements of signal-to-noise ratio (SNR) and contrast factor were calculated and these were compared to in vivo values. The T2∗ and T 1 (mean ± standard deviation) of the photopolymer resin was found to be 411 ± 19 μs and 74.39 ± 13.88 ms, respectively, and demonstrated no statistically significant change during 4 months of monitoring. The resin had a similar T2∗ decay to human cortical bone; however, had lower T 1 properties. The bone water concentration of the resin was 59% relative to an external water reference phantom, and this was higher than in vivo values reported for human cortical

  16. Human thermoregulation model of RF-EMF interaction

    International Nuclear Information System (INIS)

    Niedermayr, F.

    2012-01-01

    A thermal model has been developed which allows accurate temperature computations in high resolution anatomical models. The model is based on the basic thermal model described by Pennes which neglects any of the thermoregulatory mechanisms in humans. The thermal model developed here overcomes major simplifications by the mathematical consideration of these mechanisms which is needed for modeling a physiologically correct reaction to a thermal stimulus. The local blood perfusion, as well as the local metabolic rate, is modified as a function of the local tissue temperature. The model implemented increases the blood temperature on the basis of the absorbed energy. The heat exchange at the tissue/air interface, including the skin and respiratory tract, is also improved. The model takes not only the heat dissipation by radiation, conduction and convection into consideration but also the insensible loss of water by evaporation. Furthermore, the thermal model also accounts for the active heat dissipation by sweating. The generic implementation of the thermal model makes it possible to use it for different human models (children, adults, pregnant women) and it is also possible to take implants into consideration. The performance of the model is validated by comparing the simulation results to actual temperature measurements in humans. The thermal model is used to compute the temperature elevation in humans exposed to radiofrequency electromagnetic fields. Until now, the tissue heating caused by radiofrequency electromagnetic fields could only be estimated by a surrogate, namely the specific absorption rate. The temperature elevations in children of different sizes and ages as well as pregnant women at different gestational stages exposed to plane waves is computed. Furthermore, the temperature elevation in human bodies is computed for a diagnostic modality (magnetic resonance imaging) and a therapeutic modality (medical diathermy). (author) [de

  17. Evaluation of human thorax FE model in various impact scenarios

    Directory of Open Access Journals (Sweden)

    Jansová M.

    2015-06-01

    Full Text Available The study focused on the validation of the 50th percentile male model — a detailed FE model of the thoracic segment of the human body developed within project Development of a Finite Element Model of the Human Thorax and Upper Extremities (THOMO co-funded by the European Commission (7th Framework Programme. The model response was tested in three impact scenarios: frontal, lateral and oblique. The resulting impactor contact force vs. time and chest deflection vs. time responses were compared with experimental results. The strain profile of the 5th rib was checked with lateral and oblique strain profiles from post-mortem human subject (PMHS experiments. The influence of heart and lungs on the mechanical response of the model was assessed and the material data configuration, giving the most biofidelic thorax behaviour, was identified.

  18. Using Human Induced Pluripotent Stem Cells to Model Skeletal Diseases.

    Science.gov (United States)

    Barruet, Emilie; Hsiao, Edward C

    2016-01-01

    Musculoskeletal disorders affecting the bones and joints are major health problems among children and adults. Major challenges such as the genetic origins or poor diagnostics of severe skeletal disease hinder our understanding of human skeletal diseases. The recent advent of human induced pluripotent stem cells (human iPS cells) provides an unparalleled opportunity to create human-specific models of human skeletal diseases. iPS cells have the ability to self-renew, allowing us to obtain large amounts of starting material, and have the potential to differentiate into any cell types in the body. In addition, they can carry one or more mutations responsible for the disease of interest or be genetically corrected to create isogenic controls. Our work has focused on modeling rare musculoskeletal disorders including fibrodysplasia ossificans progressive (FOP), a congenital disease of increased heterotopic ossification. In this review, we will discuss our experiences and protocols differentiating human iPS cells toward the osteogenic lineage and their application to model skeletal diseases. A number of critical challenges and exciting new approaches are also discussed, which will allow the skeletal biology field to harness the potential of human iPS cells as a critical model system for understanding diseases of abnormal skeletal formation and bone regeneration.

  19. Monte Carlo modeling of human tooth optical coherence tomography imaging

    International Nuclear Information System (INIS)

    Shi, Boya; Meng, Zhuo; Wang, Longzhi; Liu, Tiegen

    2013-01-01

    We present a Monte Carlo model for optical coherence tomography (OCT) imaging of human tooth. The model is implemented by combining the simulation of a Gaussian beam with simulation for photon propagation in a two-layer human tooth model with non-parallel surfaces through a Monte Carlo method. The geometry and the optical parameters of the human tooth model are chosen on the basis of the experimental OCT images. The results show that the simulated OCT images are qualitatively consistent with the experimental ones. Using the model, we demonstrate the following: firstly, two types of photons contribute to the information of morphological features and noise in the OCT image of a human tooth, respectively. Secondly, the critical imaging depth of the tooth model is obtained, and it is found to decrease significantly with increasing mineral loss, simulated as different enamel scattering coefficients. Finally, the best focus position is located below and close to the dental surface by analysis of the effect of focus positions on the OCT signal and critical imaging depth. We anticipate that this modeling will become a powerful and accurate tool for a preliminary numerical study of the OCT technique on diseases of dental hard tissue in human teeth. (paper)

  20. Interactive Modelling and Simulation of Human Motion

    DEFF Research Database (Denmark)

    Engell-Nørregård, Morten Pol

    menneskers led, der udviser både ikke-konveksitet og flere frihedsgrader • En generel og alsidig model for aktivering af bløde legemer. Modellen kan anvendes som et animations værktøj, men er lige så velegnet til simulering af menneskelige muskler, da den opfylder de grundlæggende fysiske principper......Dansk resumé Denne ph.d.-afhandling beskæftiger sig med modellering og simulation af menneskelig bevægelse. Emnerne i denne afhandling har mindst to ting til fælles. For det første beskæftiger de sig med menneskelig bevægelse. Selv om de udviklede modeller også kan benyttes til andre ting,er det...... primære fokus på at modellere den menneskelige krop. For det andet, beskæftiger de sig alle med simulering som et redskab til at syntetisere bevægelse og dermed skabe animationer. Dette er en vigtigt pointe, da det betyder, at vi ikke kun skaber værktøjer til animatorer, som de kan bruge til at lave sjove...

  1. Mimicking Neurotransmitter Release in Chemical Synapses via Hysteresis Engineering in MoS2 Transistors.

    Science.gov (United States)

    Arnold, Andrew J; Razavieh, Ali; Nasr, Joseph R; Schulman, Daniel S; Eichfeld, Chad M; Das, Saptarshi

    2017-03-28

    Neurotransmitter release in chemical synapses is fundamental to diverse brain functions such as motor action, learning, cognition, emotion, perception, and consciousness. Moreover, improper functioning or abnormal release of neurotransmitter is associated with numerous neurological disorders such as epilepsy, sclerosis, schizophrenia, Alzheimer's disease, and Parkinson's disease. We have utilized hysteresis engineering in a back-gated MoS 2 field effect transistor (FET) in order to mimic such neurotransmitter release dynamics in chemical synapses. All three essential features, i.e., quantal, stochastic, and excitatory or inhibitory nature of neurotransmitter release, were accurately captured in our experimental demonstration. We also mimicked an important phenomenon called long-term potentiation (LTP), which forms the basis of human memory. Finally, we demonstrated how to engineer the LTP time by operating the MoS 2 FET in different regimes. Our findings could provide a critical component toward the design of next-generation smart and intelligent human-like machines and human-machine interfaces.

  2. Huge Dermatofibrosarcoma Protuberans Mimicking a Breast Malignant Tumor with Abscess

    Directory of Open Access Journals (Sweden)

    Han-Kun Chen

    2014-12-01

    Full Text Available Dermatofibrosarcoma protuberans (DFSP is an uncommon skin cancer that most commonly occurs on the trunk and extremities. DFSP of the breast has rarely been reported, and then is almost always of small size. We report a case of rapid-growing DFSP of the breast with abscess formation mimicking breast cancer, and also make a review of related literature.

  3. Ectopic decidual reaction mimicking inguinal lymphoma on ultrasound

    DEFF Research Database (Denmark)

    Lorentzen, C.; Prangsgaard, Tina; Lorentzen, Torben

    2014-01-01

    Ectopic decidual reaction has been described in various intraperitoneal locations. We present a case of unusual ectopic decidual reaction in the groin mimicking inguinal lymphoma on ultrasound in a pregnant woman. This case contributes evidence illustrating the variability of the clinical...... presentation of ectopic decidual reaction....

  4. Cutaneous Silicone Granuloma Mimicking Breast Cancer after Ruptured Breast Implant

    Directory of Open Access Journals (Sweden)

    Waseem Asim Ghulam El-Charnoubi

    2011-01-01

    Full Text Available Cutaneous manifestations due to migration of silicone from ruptured implants are rare. Migrated silicone with cutaneous involvement has been found in the chest wall, abdominal wall, and lower extremities. We describe a case of cutaneous silicone granuloma in the breast exhibiting unusual growth mimicking breast cancer after a ruptured implant.

  5. Neoplastic stomach lesions and their mimickers: spectrum of imaging manifestations

    OpenAIRE

    Virmani, Vivek; Khandelwal, Ashish; Sethi, Vineeta; Fraser-Hill, Margret; Fasih, Najla; Kielar, Ania

    2012-01-01

    Abstract This review illustrates a wide spectrum of gastric neoplasms with emphasis on imaging findings helpful in characterizing various gastric neoplasms. Both the malignant and benign neoplasms along with focal gastric masses mimicking tumour are illustrated. Moreover, imaging clues to reach an accurate diagnosis are emphasized.

  6. Effects of mimicking: Acting prosocially by being emotionally moved

    NARCIS (Netherlands)

    Stel, M.; Baaren, R.B. van; Vonk, R.

    2008-01-01

    Mimicry is functional for empathy and bonding purposes. Studies on the consequences of mimicry at a behavioral level demonstrated that mimicry increases prosocial behavior. However, these previous studies focused on the mimickee. In the present paper, we investigated whether mimickers also become

  7. Spinal MRI of vincristine neuropathy mimicking Guillain-Barre syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Yun Woo; Yoon, Hye-Kyung; Cho, Jae Min [Department of Radiology, Samsung Medical Centre, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Kangnam-gu, Seoul 135-710 (Korea); Sung, Ki Woong [Department of Paediatrics, Samsung Medical Centre, Seoul 135-710 (Korea)

    2003-11-01

    A 4.3-year-old girl with acute leukaemia, who was being treated with chemotherapy (including vincristine), developed paraplegia. Spinal MRI showed diffusely enhancing nerve roots on contrast-enhanced images. Spinal fluid analysis showed a normal protein level. Vincristine neuropathy mimicking Guillain-Barre syndrome is thought to be the cause of the MRI abnormalities. (orig.)

  8. Spinal MRI of vincristine neuropathy mimicking Guillain-Barre syndrome

    International Nuclear Information System (INIS)

    Chang, Yun Woo; Yoon, Hye-Kyung; Cho, Jae Min; Sung, Ki Woong

    2003-01-01

    A 4.3-year-old girl with acute leukaemia, who was being treated with chemotherapy (including vincristine), developed paraplegia. Spinal MRI showed diffusely enhancing nerve roots on contrast-enhanced images. Spinal fluid analysis showed a normal protein level. Vincristine neuropathy mimicking Guillain-Barre syndrome is thought to be the cause of the MRI abnormalities. (orig.)

  9. Cutaneous lymphoid hyperplasia mimicking cutaneous lymphoma in a hyperthyroid cat

    OpenAIRE

    Snead, Elisabeth; Kerr, Moira; MacDonald, Valerie

    2013-01-01

    A 12-year-old neutered male domestic shorthair cat presented for chronic, localized, swelling and crusting of the left upper lip, weight loss, sporadic vomiting, and focal alopecia between the scapulae was diagnosed with hyperthyroidism and regional eosinophilic lymphadenitis. Treatment with methimazole exacerbated an underlying hypersensitivity disorder leading to marked generalized lymphadenopathy that histologically mimicked lymphoma.

  10. Friedreich's ataxia mimicking hereditary motor and sensory neuropathy.

    Science.gov (United States)

    Panas, Marios; Kalfakis, Nikolaos; Karadima, Georgia; Davaki, Panagiota; Vassilopoulos, Demetris

    2002-11-01

    Four patients from three unrelated families, with clinical and electrophysiological findings compatible with the diagnosis of hereditary motor and sensory neuropathy, are presented. The molecular analysis showed that the affected individuals were homozygous for the mutation in the X25 gene, characteristic of Friedreich's ataxia. These patients seem to represent a form of Friedreich's ataxia mimicking Charcot-Marie-Tooth disease.

  11. Primary Papillary Mucinous Adenocarcinoma of the Ureter Mimicking Genitourinary Tuberculosis

    Science.gov (United States)

    Gulwani, Hanni; Jain, Aruna

    2010-01-01

    Primary adenocarcinomas of the renal pelvis and ureter are rare and account for less than 1% of all malignancies at this site. We report a case of primary papillary mucinous adenocarcinoma of the ureter that clinically mimicked genitourinary tuberculosis. Early diagnosis is important for the better outcome. PMID:21151719

  12. Primary Papillary Mucinous Adenocarcinoma of the Ureter Mimicking Genitourinary Tuberculosis

    Directory of Open Access Journals (Sweden)

    Hanni Gulwani

    2010-01-01

    Full Text Available Primary adenocarcinomas of the renal pelvis and ureter are rare and account for less than 1% of all malignancies at this site. We report a case of primary papillary mucinous adenocarcinoma of the ureter that clinically mimicked genitourinary tuberculosis. Early diagnosis is important for the better outcome.

  13. Mimicking expressiveness of movements by autistic children in game play

    NARCIS (Netherlands)

    Tetteroo, D.; Shirzad, A.; Serras Pereira, M.; Zwinderman, M.J.; Duy, L.; Barakova, E.I.

    2012-01-01

    Children with Autistic Spectrum Disorder (ASD)have marked impairments in social interaction. Imitation is a basic social interaction behavior, and mimicking as an element of imitation can be a diagnostic marker for autism and thus a skill that can be targeted by behavioral training. In a comparative

  14. Breast cancer cell behaviors on staged tumorigenesis-mimicking matrices derived from tumor cells at various malignant stages

    Energy Technology Data Exchange (ETDEWEB)

    Hoshiba, Takashi [Graduate School of Science and Engineering, Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata 992-8510 (Japan); International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Tanaka, Masaru, E-mail: tanaka@yz.yamagata-u.ac.jp [Graduate School of Science and Engineering, Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata 992-8510 (Japan)

    2013-09-20

    Highlights: •Models mimicking ECM in tumor with different malignancy were prepared. •Cancer cell proliferation was suppressed on benign tumor ECM. •Benign tumor cell proliferation was suppressed on cancerous ECM. •Chemoresistance of cancer cell was enhanced on cancerous ECM. -- Abstract: Extracellular matrix (ECM) has been focused to understand tumor progression in addition to the genetic mutation of cancer cells. Here, we prepared “staged tumorigenesis-mimicking matrices” which mimic in vivo ECM in tumor tissue at each malignant stage to understand the roles of ECM in tumor progression. Breast tumor cells, MDA-MB-231 (invasive), MCF-7 (non-invasive), and MCF-10A (benign) cells, were cultured to form their own ECM beneath the cells and formed ECM was prepared as staged tumorigenesis-mimicking matrices by decellularization treatment. Cells showed weak attachment on the matrices derived from MDA-MB-231 cancer cells. The proliferations of MDA-MB-231 and MCF-7 was promoted on the matrices derived from MDA-MB-231 cancer cells whereas MCF-10A cell proliferation was not promoted. MCF-10A cell proliferation was promoted on the matrices derived from MCF-10A cells. Chemoresistance of MDA-MB-231 cells against 5-fluorouracil increased on only matrices derived from MDA-MB-231 cells. Our results showed that the cells showed different behaviors on staged tumorigenesis-mimicking matrices according to the malignancy of cell sources for ECM preparation. Therefore, staged tumorigenesis-mimicking matrices might be a useful in vitro ECM models to investigate the roles of ECM in tumor progression.

  15. Breast cancer cell behaviors on staged tumorigenesis-mimicking matrices derived from tumor cells at various malignant stages

    International Nuclear Information System (INIS)

    Hoshiba, Takashi; Tanaka, Masaru

    2013-01-01

    Highlights: •Models mimicking ECM in tumor with different malignancy were prepared. •Cancer cell proliferation was suppressed on benign tumor ECM. •Benign tumor cell proliferation was suppressed on cancerous ECM. •Chemoresistance of cancer cell was enhanced on cancerous ECM. -- Abstract: Extracellular matrix (ECM) has been focused to understand tumor progression in addition to the genetic mutation of cancer cells. Here, we prepared “staged tumorigenesis-mimicking matrices” which mimic in vivo ECM in tumor tissue at each malignant stage to understand the roles of ECM in tumor progression. Breast tumor cells, MDA-MB-231 (invasive), MCF-7 (non-invasive), and MCF-10A (benign) cells, were cultured to form their own ECM beneath the cells and formed ECM was prepared as staged tumorigenesis-mimicking matrices by decellularization treatment. Cells showed weak attachment on the matrices derived from MDA-MB-231 cancer cells. The proliferations of MDA-MB-231 and MCF-7 was promoted on the matrices derived from MDA-MB-231 cancer cells whereas MCF-10A cell proliferation was not promoted. MCF-10A cell proliferation was promoted on the matrices derived from MCF-10A cells. Chemoresistance of MDA-MB-231 cells against 5-fluorouracil increased on only matrices derived from MDA-MB-231 cells. Our results showed that the cells showed different behaviors on staged tumorigenesis-mimicking matrices according to the malignancy of cell sources for ECM preparation. Therefore, staged tumorigenesis-mimicking matrices might be a useful in vitro ECM models to investigate the roles of ECM in tumor progression

  16. A model for assessing human cognitive reliability in PRA studies

    International Nuclear Information System (INIS)

    Hannaman, G.W.; Spurgin, A.J.; Lukic, Y.

    1985-01-01

    This paper summarizes the status of a research project sponsored by EPRI as part of the Probabilistic Risk Assessment (PRA) technology improvement program and conducted by NUS Corporation to develop a model of Human Cognitive Reliability (HCR). The model was synthesized from features identified in a review of existing models. The model development was based on the hypothesis that the key factors affecting crew response times are separable. The inputs to the model consist of key parameters the values of which can be determined by PRA analysts for each accident situation being assessed. The output is a set of curves which represent the probability of control room crew non-response as a function of time for different conditions affecting their performance. The non-response probability is then a contributor to the overall non-success of operating crews to achieve a functional objective identified in the PRA study. Simulator data and some small scale tests were utilized to illustrate the calibration of interim HCR model coefficients for different types of cognitive processing since the data were sparse. The model can potentially help PRA analysts make human reliability assessments more explicit. The model incorporates concepts from psychological models of human cognitive behavior, information from current collections of human reliability data sources and crew response time data from simulator training exercises

  17. Lumped parametric model of the human ear for sound transmission.

    Science.gov (United States)

    Feng, Bin; Gan, Rong Z

    2004-09-01

    A lumped parametric model of the human auditoria peripherals consisting of six masses suspended with six springs and ten dashpots was proposed. This model will provide the quantitative basis for the construction of a physical model of the human middle ear. The lumped model parameters were first identified using published anatomical data, and then determined through a parameter optimization process. The transfer function of the middle ear obtained from human temporal bone experiments with laser Doppler interferometers was used for creating the target function during the optimization process. It was found that, among 14 spring and dashpot parameters, there were five parameters which had pronounced effects on the dynamic behaviors of the model. The detailed discussion on the sensitivity of those parameters was provided with appropriate applications for sound transmission in the ear. We expect that the methods for characterizing the lumped model of the human ear and the model parameters will be useful for theoretical modeling of the ear function and construction of the ear physical model.

  18. Interfacing polymeric scaffolds with primary pancreatic ductal adenocarcinoma cells to develop 3D cancer models

    NARCIS (Netherlands)

    Ricci, C.; Mota, C.M.; Moscato, S.; D' Alessandro, D.; Ugel, S.; Sartoris, S.; Bronte, V.; Boggi, U.; Campani, D.; Funel, N.; Moroni, Lorenzo; Danti, S.

    2014-01-01

    We analyzed the interactions between human primary cells from pancreatic ductal adenocarcinoma (PDAC) and polymeric scaffolds to develop 3D cancer models useful for mimicking the biology of this tumor. Three scaffold types based on two biocompatible polymeric formulations, such as poly(vinyl

  19. Modeling aspects of human memory for scientific study.

    Energy Technology Data Exchange (ETDEWEB)

    Caudell, Thomas P. (University of New Mexico); Watson, Patrick (University of Illinois - Champaign-Urbana Beckman Institute); McDaniel, Mark A. (Washington University); Eichenbaum, Howard B. (Boston University); Cohen, Neal J. (University of Illinois - Champaign-Urbana Beckman Institute); Vineyard, Craig Michael; Taylor, Shawn Ellis; Bernard, Michael Lewis; Morrow, James Dan; Verzi, Stephen J.

    2009-10-01

    Working with leading experts in the field of cognitive neuroscience and computational intelligence, SNL has developed a computational architecture that represents neurocognitive mechanisms associated with how humans remember experiences in their past. The architecture represents how knowledge is organized and updated through information from individual experiences (episodes) via the cortical-hippocampal declarative memory system. We compared the simulated behavioral characteristics with those of humans measured under well established experimental standards, controlling for unmodeled aspects of human processing, such as perception. We used this knowledge to create robust simulations of & human memory behaviors that should help move the scientific community closer to understanding how humans remember information. These behaviors were experimentally validated against actual human subjects, which was published. An important outcome of the validation process will be the joining of specific experimental testing procedures from the field of neuroscience with computational representations from the field of cognitive modeling and simulation.

  20. Human pluripotent stem cells: an emerging model in developmental biology.

    Science.gov (United States)

    Zhu, Zengrong; Huangfu, Danwei

    2013-02-01

    Developmental biology has long benefited from studies of classic model organisms. Recently, human pluripotent stem cells (hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, have emerged as a new model system that offers unique advantages for developmental studies. Here, we discuss how studies of hPSCs can complement classic approaches using model organisms, and how hPSCs can be used to recapitulate aspects of human embryonic development 'in a dish'. We also summarize some of the recently developed genetic tools that greatly facilitate the interrogation of gene function during hPSC differentiation. With the development of high-throughput screening technologies, hPSCs have the potential to revolutionize gene discovery in mammalian development.

  1. Modelling the basic error tendencies of human operators

    International Nuclear Information System (INIS)

    Reason, J.

    1988-01-01

    The paper outlines the primary structural features of human cognition: a limited, serial workspace interacting with a parallel distributed knowledge base. It is argued that the essential computational features of human cognition - to be captured by an adequate operator model - reside in the mechanisms by which stored knowledge structures are selected and brought into play. Two such computational 'primitives' are identified: similarity-matching and frequency-gambling. These two retrieval heuristics, it is argued, shape both the overall character of human performance (i.e. its heavy reliance on pattern-matching) and its basic error tendencies ('strong-but-wrong' responses, confirmation, similarity and frequency biases, and cognitive 'lock-up'). The various features of human cognition are integrated with a dynamic operator model capable of being represented in software form. This computer model, when run repeatedly with a variety of problem configurations, should produce a distribution of behaviours which, in total, simulate the general character of operator performance. (author)

  2. Modelling the basic error tendencies of human operators

    International Nuclear Information System (INIS)

    Reason, James

    1988-01-01

    The paper outlines the primary structural features of human cognition: a limited, serial workspace interacting with a parallel distributed knowledge base. It is argued that the essential computational features of human cognition - to be captured by an adequate operator model - reside in the mechanisms by which stored knowledge structures are selected and brought into play. Two such computational 'primitives' are identified: similarity-matching and frequency-gambling. These two retrieval heuristics, it is argued, shape both the overall character of human performance (i.e. its heavy reliance on pattern-matching) and its basic error tendencies ('strong-but-wrong' responses, confirmation, similarity and frequency biases, and cognitive 'lock-up'). The various features of human cognition are integrated with a dynamic operator model capable of being represented in software form. This computer model, when run repeatedly with a variety of problem configurations, should produce a distribution of behaviours which, in toto, simulate the general character of operator performance. (author)

  3. A novel polar-based human face recognition computational model

    Directory of Open Access Journals (Sweden)

    Y. Zana

    2009-07-01

    Full Text Available Motivated by a recently proposed biologically inspired face recognition approach, we investigated the relation between human behavior and a computational model based on Fourier-Bessel (FB spatial patterns. We measured human recognition performance of FB filtered face images using an 8-alternative forced-choice method. Test stimuli were generated by converting the images from the spatial to the FB domain, filtering the resulting coefficients with a band-pass filter, and finally taking the inverse FB transformation of the filtered coefficients. The performance of the computational models was tested using a simulation of the psychophysical experiment. In the FB model, face images were first filtered by simulated V1- type neurons and later analyzed globally for their content of FB components. In general, there was a higher human contrast sensitivity to radially than to angularly filtered images, but both functions peaked at the 11.3-16 frequency interval. The FB-based model presented similar behavior with regard to peak position and relative sensitivity, but had a wider frequency band width and a narrower response range. The response pattern of two alternative models, based on local FB analysis and on raw luminance, strongly diverged from the human behavior patterns. These results suggest that human performance can be constrained by the type of information conveyed by polar patterns, and consequently that humans might use FB-like spatial patterns in face processing.

  4. Meeting Human Reliability Requirements through Human Factors Design, Testing, and Modeling

    Energy Technology Data Exchange (ETDEWEB)

    R. L. Boring

    2007-06-01

    In the design of novel systems, it is important for the human factors engineer to work in parallel with the human reliability analyst to arrive at the safest achievable design that meets design team safety goals and certification or regulatory requirements. This paper introduces the System Development Safety Triptych, a checklist of considerations for the interplay of human factors and human reliability through design, testing, and modeling in product development. This paper also explores three phases of safe system development, corresponding to the conception, design, and implementation of a system.

  5. Discrete time modelization of human pilot behavior

    Science.gov (United States)

    Cavalli, D.; Soulatges, D.

    1975-01-01

    This modelization starts from the following hypotheses: pilot's behavior is a time discrete process, he can perform only one task at a time and his operating mode depends on the considered flight subphase. Pilot's behavior was observed using an electro oculometer and a simulator cockpit. A FORTRAN program has been elaborated using two strategies. The first one is a Markovian process in which the successive instrument readings are governed by a matrix of conditional probabilities. In the second one, strategy is an heuristic process and the concepts of mental load and performance are described. The results of the two aspects have been compared with simulation data.

  6. Humanized Mouse Model of Ebola Virus Disease Mimics the Immune Responses in Human Disease.

    Science.gov (United States)

    Bird, Brian H; Spengler, Jessica R; Chakrabarti, Ayan K; Khristova, Marina L; Sealy, Tara K; Coleman-McCray, JoAnn D; Martin, Brock E; Dodd, Kimberly A; Goldsmith, Cynthia S; Sanders, Jeanine; Zaki, Sherif R; Nichol, Stuart T; Spiropoulou, Christina F

    2016-03-01

    Animal models recapitulating human Ebola virus disease (EVD) are critical for insights into virus pathogenesis. Ebola virus (EBOV) isolates derived directly from human specimens do not, without adaptation, cause disease in immunocompetent adult rodents. Here, we describe EVD in mice engrafted with human immune cells (hu-BLT). hu-BLT mice developed EVD following wild-type EBOV infection. Infection with high-dose EBOV resulted in rapid, lethal EVD with high viral loads, alterations in key human antiviral immune cytokines and chemokines, and severe histopathologic findings similar to those shown in the limited human postmortem data available. A dose- and donor-dependent clinical course was observed in hu-BLT mice infected with lower doses of either Mayinga (1976) or Makona (2014) isolates derived from human EBOV cases. Engraftment of the human cellular immune system appeared to be essential for the observed virulence, as nonengrafted mice did not support productive EBOV replication or develop lethal disease. hu-BLT mice offer a unique model for investigating the human immune response in EVD and an alternative animal model for EVD pathogenesis studies and therapeutic screening. Published by Oxford University Press for the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  7. 3D virtual human rapid modeling method based on top-down modeling mechanism

    Directory of Open Access Journals (Sweden)

    LI Taotao

    2017-01-01

    Full Text Available Aiming to satisfy the vast custom-made character demand of 3D virtual human and the rapid modeling in the field of 3D virtual reality, a new virtual human top-down rapid modeling method is put for-ward in this paper based on the systematic analysis of the current situation and shortage of the virtual hu-man modeling technology. After the top-level realization of virtual human hierarchical structure frame de-sign, modular expression of the virtual human and parameter design for each module is achieved gradu-al-level downwards. While the relationship of connectors and mapping restraints among different modules is established, the definition of the size and texture parameter is also completed. Standardized process is meanwhile produced to support and adapt the virtual human top-down rapid modeling practice operation. Finally, the modeling application, which takes a Chinese captain character as an example, is carried out to validate the virtual human rapid modeling method based on top-down modeling mechanism. The result demonstrates high modelling efficiency and provides one new concept for 3D virtual human geometric mod-eling and texture modeling.

  8. Optimization of micro-fabricated porous membranes for intestinal epithelial cell culture and in vitro modeling of the human intestinal barrier

    Science.gov (United States)

    Nair Gourikutty Sajay, Bhuvanendran; Yin, Chiam Su; Ramadan, Qasem

    2017-12-01

    In vitro modeling of organs could provide a controlled platform for studying physiological events and has great potential in the field of pharmaceutical development. Here, we describe the characterization of in vitro modeling of the human intestinal barrier mimicked using silicon porous membranes as a substrate. To mimic an intestinal in vivo setup as closely as possible, a porous substrate is required in a dynamic environment for the cells to grow rather than a static setup with an impermeable surface such as a petri dish. In this study, we focus on the detailed characterization of Caco-2 cells cultured on a silicon membrane with different pore sizes as well as the effect of dynamic fluid flow on the model. The porous silicon membrane together with continuous perfusion of liquid applying shear stress on the cells enhances the differentiation of polarized cells by providing access to the both their basal and apical surfaces. Membranes with pore sizes of 0.5-3 µm were used and a shear stress of ~0.03 dyne cm-2 was created by applying a low flow rate of 20 nl s-1. By providing these optimized conditions, cells were able to differentiate with columnar morphology, which developed microvilli structures on their apical side and tight junctions between adjacent cells like those in a healthy human intestinal barrier. In this setup, it is possible to study the important cellular functions of the intestine such as transport, absorption and secretion, and thus this model has great potential in drug screening.

  9. A human lung xenograft mouse model of Nipah virus infection.

    Directory of Open Access Journals (Sweden)

    Gustavo Valbuena

    2014-04-01

    Full Text Available Nipah virus (NiV is a member of the genus Henipavirus (family Paramyxoviridae that causes severe and often lethal respiratory illness and encephalitis in humans with high mortality rates (up to 92%. NiV can cause Acute Lung Injury (ALI in humans, and human-to-human transmission has been observed in recent outbreaks of NiV. While the exact route of transmission to humans is not known, we have previously shown that NiV can efficiently infect human respiratory epithelial cells. The molecular mechanisms of NiV-associated ALI in the human respiratory tract are unknown. Thus, there is an urgent need for models of henipavirus infection of the human respiratory tract to study the pathogenesis and understand the host responses. Here, we describe a novel human lung xenograft model in mice to study the pathogenesis of NiV. Following transplantation, human fetal lung xenografts rapidly graft and develop mature structures of adult lungs including cartilage, vascular vessels, ciliated pseudostratified columnar epithelium, and primitive "air" spaces filled with mucus and lined by cuboidal to flat epithelium. Following infection, NiV grows to high titers (10(7 TCID50/gram lung tissue as early as 3 days post infection (pi. NiV targets both the endothelium as well as respiratory epithelium in the human lung tissues, and results in syncytia formation. NiV infection in the human lung results in the production of several cytokines and chemokines including IL-6, IP-10, eotaxin, G-CSF and GM-CSF on days 5 and 7 pi. In conclusion, this study demonstrates that NiV can replicate to high titers in a novel in vivo model of the human respiratory tract, resulting in a robust inflammatory response, which is known to be associated with ALI. This model will facilitate progress in the fundamental understanding of henipavirus pathogenesis and virus-host interactions; it will also provide biologically relevant models for other respiratory viruses.

  10. Mathematical Analysis of a Model for Human Immunodeficiency ...

    African Journals Online (AJOL)

    ADOWIE PERE

    ABSTRACT: The objective of this paper is to present a mathematical model formulated to investigate the dynamics of human immunodeficiency virus (HIV). The disease free equilibrium of the model was found to be locally and globally asymptotically stable. The endemic equilibrium point exists and it was discovered that the ...

  11. Computational 3-D Model of the Human Respiratory System

    Science.gov (United States)

    We are developing a comprehensive, morphologically-realistic computational model of the human respiratory system that can be used to study the inhalation, deposition, and clearance of contaminants, while being adaptable for age, race, gender, and health/disease status. The model ...

  12. Gene therapy in nonhuman primate models of human autoimmune disease

    NARCIS (Netherlands)

    t'Hart, B. A.; Vervoordeldonk, M.; Heeney, J. L.; Tak, P. P.

    2003-01-01

    Before autoimmune diseases in humans can be treated with gene therapy, the safety and efficacy of the used vectors must be tested in valid experimental models. Monkeys, such as the rhesus macaque or the common marmoset, provide such models. This publication reviews the state of the art in monkey

  13. Three Models of Education: Rights, Capabilities and Human Capital

    Science.gov (United States)

    Robeyns, Ingrid

    2006-01-01

    This article analyses three normative accounts that can underlie educational policies, with special attention to gender issues. These three models of education are human capital theory, rights discourses and the capability approach. I first outline five different roles that education can play. Then I analyse these three models of educational…

  14. Numerical human model for impact and seating comfort

    NARCIS (Netherlands)

    Hoof, J.F.A.M. van; Lange, R. de; Verver, M.M.

    2003-01-01

    This paper presents a detailed numerical model of the human body that can be used to evaluate both safety and comfort aspects of vehicle interiors. The model is based on a combination of rigid body and finite element techniques to provide an optimal combination of computational efficiency and

  15. Mouse Models as Predictors of Human Responses: Evolutionary Medicine.

    Science.gov (United States)

    Uhl, Elizabeth W; Warner, Natalie J

    Mice offer a number of advantages and are extensively used to model human diseases and drug responses. Selective breeding and genetic manipulation of mice have made many different genotypes and phenotypes available for research. However, in many cases, mouse models have failed to be predictive. Important sources of the prediction problem have been the failure to consider the evolutionary basis for species differences, especially in drug metabolism, and disease definitions that do not reflect the complexity of gene expression underlying disease phenotypes. Incorporating evolutionary insights into mouse models allow for unique opportunities to characterize the effects of diet, different gene expression profiles, and microbiomics underlying human drug responses and disease phenotypes.

  16. Geometry Modeling Program Implementation of Human Hip Tissue

    Directory of Open Access Journals (Sweden)

    WANG Mo-nan

    2017-10-01

    Full Text Available Abstract:Aiming to design a simulate software of human tissue modeling and analysis,Visual Studio 2010 is selected as a development tool to develop a 3 D reconstruction software of human tissue with language C++.It can be used alone. It also can be a module of the virtual surgery systems. The system includes medical image segmentation modules and 3 D reconstruction modules,and can realize the model visualization. This software system has been used to reconstruct hip muscles,femur and hip bone accurately. The results show these geometry models can simulate the structure of hip tissues.

  17. Geometry Modeling Program Implementation of Human Hip Tissue

    Directory of Open Access Journals (Sweden)

    WANG Monan

    2017-04-01

    Full Text Available Aiming to design a simulate software of human tissue modeling and analysis,Visual Studio 2010 is selected as a development tool to develop a 3 D reconstruction software of human tissue with language C++.It can be used alone. It also can be a module of the virtual surgery systems. The system includes medical image segmentation modules and 3 D reconstruction modules,and can realize the model visualization. This software system has been used to reconstruct hip muscles,femur and hip bone accurately. The results show these geometry models can simulate the structure of hip tissues.

  18. Human Lipoproteins at Model Cell Membranes

    DEFF Research Database (Denmark)

    Browning, K L; Lind, T K; Maric, S

    2017-01-01

    High and low density lipoproteins (HDL and LDL) are thought to play vital roles in the onset and development of atherosclerosis; the biggest killer in the western world. Key issues of initial lipoprotein (LP) interactions at cellular membranes need to be addressed including LP deposition and lipid...... exchange. Here we present a protocol for monitoring the in situ kinetics of lipoprotein deposition and lipid exchange/removal at model cellular membranes using the non-invasive, surface sensitive methods of neutron reflection and quartz crystal microbalance with dissipation. For neutron reflection, lipid...... support the notion of HDL acting as the 'good' cholesterol, removing lipid material from lipid-loaded cells, whereas LDL acts as the 'bad' cholesterol, depositing lipid material into the vascular wall....

  19. Modeling Human Behavior to Anticipate Insider Attacks

    Directory of Open Access Journals (Sweden)

    Ryan E Hohimer

    2011-01-01

    Full Text Available The insider threat ranks among the most pressing cyber-security challenges that threaten government and industry information infrastructures. To date, no systematic methods have been developed that provide a complete and effective approach to prevent data leakage, espionage, and sabotage. Current practice is forensic in nature, relegating to the analyst the bulk of the responsibility to monitor, analyze, and correlate an overwhelming amount of data. We describe a predictive modeling framework that integrates a diverse set of data sources from the cyber domain, as well as inferred psychological/motivational factors that may underlie malicious insider exploits. This comprehensive threat assessment approach provides automated support for the detection of high-risk behavioral "triggers" to help focus the analyst's attention and inform the analysis. Designed to be domain-independent, the system may be applied to many different threat and warning analysis/sense-making problems.

  20. A Systems Model for Teaching Human Resource Management

    Directory of Open Access Journals (Sweden)

    George R. Greene

    2013-07-01

    Full Text Available Efficient and effective human resource management is a complex, involved, and interactive process. This article presents and discusses a unique systems approach model for teaching human resource (people management processes, and the important inter-relationships within that process. The model contains two unique components related to key sub-processes: incentives management and performance evaluation. We have not observed a model applying a systems thinking paradigm presented in any textbook, journal article, business publication, or other literature addressing the topic. For nearly three decades, the model has been used in teaching a comprehensive, meaningful understanding of the human resource management process that can be effectively implemented in both corporate and academic learning venues.

  1. Modeling and simulating human teamwork behaviors using intelligent agents

    Science.gov (United States)

    Fan, Xiaocong; Yen, John

    2004-12-01

    Among researchers in multi-agent systems there has been growing interest in using intelligent agents to model and simulate human teamwork behaviors. Teamwork modeling is important for training humans in gaining collaborative skills, for supporting humans in making critical decisions by proactively gathering, fusing, and sharing information, and for building coherent teams with both humans and agents working effectively on intelligence-intensive problems. Teamwork modeling is also challenging because the research has spanned diverse disciplines from business management to cognitive science, human discourse, and distributed artificial intelligence. This article presents an extensive, but not exhaustive, list of work in the field, where the taxonomy is organized along two main dimensions: team social structure and social behaviors. Along the dimension of social structure, we consider agent-only teams and mixed human-agent teams. Along the dimension of social behaviors, we consider collaborative behaviors, communicative behaviors, helping behaviors, and the underpinning of effective teamwork-shared mental models. The contribution of this article is that it presents an organizational framework for analyzing a variety of teamwork simulation systems and for further studying simulated teamwork behaviors.

  2. Going skin deep: A direct comparison of penetration potential of lipid-based nanovesicles on the isolated perfused human skin flap model.

    Science.gov (United States)

    Ternullo, Selenia; de Weerd, Louis; Holsæter, Ann Mari; Flaten, Gøril Eide; Škalko-Basnet, Nataša

    2017-12-01

    Phospholipid-based nanocarriers are attractive drug carriers for improved local skin therapy. In the present study, the recently developed isolated perfused human skin flap (IPHSF) model was used to directly compare the skin penetration enhancing potential of the three commonly used nanocarriers, namely conventional liposomes (CLs), deformable liposomes (DLs) and solid lipid nanoparticles (SLNs). Two fluorescent markers, calcein (hydrophilic) or rhodamine (lipophilic), were incorporated individually in the three nanosystems. The nanocarrier size ranged between 200 and 300nm; the surface charge and entrapment efficiency for both markers were dependent on the lipid composition and the employed surfactant. Both carrier-associated markers could not penetrate the full thickness human skin, confirming their suitability for dermal drug delivery. CLs exhibited higher retention of both markers on the skin surface compared to DLs and SLNs, indicating a depo formation. DLs and SLNs enabled the deeper penetration of the two markers into the skin layers. In vitro and ex vivo skin penetration studies performed on the cellophane membrane and full thickness pig/human skin, respectively, confirmed the findings. In conclusion, efficient dermal drug delivery can be achieved by optimization of a lipid nanocarrier on the suitable skin-mimicking model to assure system's accumulation in the targeted skin layer. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Autoimmunity to Tropomyosin-Specific Peptides Induced by Mycobacterium leprae in Leprosy Patients: Identification of Mimicking Proteins

    Directory of Open Access Journals (Sweden)

    Itu Singh

    2018-04-01

    Full Text Available BackgroundIt has been shown earlier that there is a rise in the levels of autoantibodies and T cell response to cytoskeletal proteins in leprosy. Our group recently demonstrated a rise in both T and B cell responses to keratin and myelin basic protein in all types of leprosy patients and their associations in type 1 reaction (T1R group of leprosy.ObjectivesIn this study, we investigated the association of levels of autoantibodies and lymphoproliferation against myosin in leprosy patients across the spectrum and tried to find out the mimicking proteins or epitopes between host protein and protein/s of Mycobacterium leprae.MethodologyOne hundred and sixty-nine leprosy patients and 55 healthy controls (HC were enrolled in the present study. Levels of anti-myosin antibodies and T-cell responses against myosin were measured by ELISA and lymphoproliferation assay, respectively. Using 2-D gel electrophoresis, western blot and MALDI-TOF/TOF antibody-reactive spots were identified. Three-dimensional structure of mimicking proteins was modeled by online server. B cell epitopes of the proteins were predicted by BCPREDS server 1.0 followed by identification of mimicking epitopes. Mice of inbred BALB/c strain were hyperimmunized with M. leprae soluble antigen (MLSA and splenocytes and lymph node cells of these animals were adoptively transferred to naïve mice.ResultsHighest level of anti-myosin antibodies was noted in sera of T1R leprosy patients. We observed significantly higher levels of lymphoproliferative response (p < 0.05 with myosin in all types of leprosy patients compared to HC. Further, hyperimmunization of inbred BALB/c strain of female mice and rabbit with MLSA revealed that both hyperimmunized rabbit and mice evoked heightened levels of antibodies against myosin and this autoimmune response could be adoptively transferred from hyperimmunized to naïve mice. Tropomyosin was found to be mimicking with ATP-dependent Clp protease ATP

  4. Physiologically Based Pharmacokinetic Model for Terbinafine in Rats and Humans

    Science.gov (United States)

    Hosseini-Yeganeh, Mahboubeh; McLachlan, Andrew J.

    2002-01-01

    The aim of this study was to develop a physiologically based pharmacokinetic (PB-PK) model capable of describing and predicting terbinafine concentrations in plasma and tissues in rats and humans. A PB-PK model consisting of 12 tissue and 2 blood compartments was developed using concentration-time data for tissues from rats (n = 33) after intravenous bolus administration of terbinafine (6 mg/kg of body weight). It was assumed that all tissues except skin and testis tissues were well-stirred compartments with perfusion rate limitations. The uptake of terbinafine into skin and testis tissues was described by a PB-PK model which incorporates a membrane permeability rate limitation. The concentration-time data for terbinafine in human plasma and tissues were predicted by use of a scaled-up PB-PK model, which took oral absorption into consideration. The predictions obtained from the global PB-PK model for the concentration-time profile of terbinafine in human plasma and tissues were in close agreement with the observed concentration data for rats. The scaled-up PB-PK model provided an excellent prediction of published terbinafine concentration-time data obtained after the administration of single and multiple oral doses in humans. The estimated volume of distribution at steady state (Vss) obtained from the PB-PK model agreed with the reported value of 11 liters/kg. The apparent volume of distribution of terbinafine in skin and adipose tissues accounted for 41 and 52%, respectively, of the Vss for humans, indicating that uptake into and redistribution from these tissues dominate the pharmacokinetic profile of terbinafine. The PB-PK model developed in this study was capable of accurately predicting the plasma and tissue terbinafine concentrations in both rats and humans and provides insight into the physiological factors that determine terbinafine disposition. PMID:12069977

  5. Development of a finite element model of the human abdomen.

    Science.gov (United States)

    Lee, J B; Yang, K H

    2001-11-01

    Currently, three-dimensional finite element models of the human body have been developed for frequently injured anatomical regions such as the brain, chest, extremities and pelvis. While a few models of the human body include the abdomen, these models have tended to oversimplify the complexity of the abdominal region. As the first step in understanding abdominal injuries via numerical methods, a 3D finite element model of a 50(th) percentile male human abdomen (WSUHAM) has been developed and validated against experimental data obtained from two sets of side impact tests and a series of frontal impact tests. The model includes a detailed representation of the liver, spleen, kidneys, spine, skin and major blood vessels. Hollow organs, such as the esophagus, stomach, small and large intestines, gallbladder, bile ducts, ureters, rectum and adrenal glands are grouped into three bodybags in order to provide realistic inertial properties and to maintain the position of the solid organs in their appropriate locations. Using direct connections, the model was joined superiorly to a partial model of the human thorax, and inferiorly to models of the human pelvis and the lower extremities that have been previously developed. Material properties for various tissues of the abdomen were derived from the literature. Data obtained in a series of cadaveric pendulum impact tests conducted at Wayne State University (WSU), a series of lateral drop tests conducted at Association Peugeot-Renault (APR) and a series of cadaveric lower abdomen frontal impact tests conducted at WSU were used to validate the model. Results predicted by the model match these experimental data for various impact speeds, impactor masses and drop heights. Further study is still needed in order to fully validate WSUHAM before it can be used to assess various impact loading conditions associated with vehicular crashes.

  6. Construction of Anterior Hemi-Corneal Equivalents Using Nontransfected Human Corneal Cells and Transplantation in Dog Models.

    Science.gov (United States)

    Xu, Bin; Song, Zhan; Fan, Tingjun

    2017-11-01

    Tissue-engineered human anterior hemi-cornea (TE-aHC) is a promising equivalent for treating anterior lamellar keratopathy to surmount the severe shortage of donated corneas. This study was intended to construct a functional TE-aHC with nontransfected human corneal stromal (ntHCS) and epithelial (ntHCEP) cells using acellular porcine corneal stromata (aPCS) as a carrier scaffold, and evaluate its biological functions in a dog model. To construct a TE-aHC, ntHCS cells were injected into an aPCS scaffold and cultured for 3 days; then, ntHCEP cells were inoculated onto the Bowman's membrane of the scaffold and cultured for 5 days under air-liquid interface condition. After its morphology and histological structure were characterized, the constructed TE-aHC was transplanted into dog eyes via lamellar keratoplasty. The corneal transparency, thickness, intraocular pressure, epithelial integrity, and corneal regeneration were monitored in vivo, and the histological structure and histochemical property were examined ex vivo 360 days after surgery, respectively. The results showed that the constructed TE-aHC was highly transparent and composed of a corneal epithelium of 7-8 layer ntHCEP cells and a corneal stroma of regularly aligned collagen fibers and well-preserved glycosaminoglycans with sparsely distributed ntHCS cells, mimicking a normal anterior hemi-cornea (aHC). Moreover, both ntHCEP and ntHCS cells maintained positive expression of their marker and functional proteins. After transplantation into dog eyes, the constructed TE-aHC acted naturally in terms of morphology, structure and inherent property, and functioned well in maintaining corneal clarity, thickness, normal histological structure, and composition in dog models by reconstructing a normal aHC, which could be used as a promising aHC equivalent in corneal regenerative medicine and aHC disorder therapy. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  7. QSAR models of human data can enrich or replace LLNA testing for human skin sensitization

    Science.gov (United States)

    Alves, Vinicius M.; Capuzzi, Stephen J.; Muratov, Eugene; Braga, Rodolpho C.; Thornton, Thomas; Fourches, Denis; Strickland, Judy; Kleinstreuer, Nicole; Andrade, Carolina H.; Tropsha, Alexander

    2016-01-01

    Skin sensitization is a major environmental and occupational health hazard. Although many chemicals have been evaluated in humans, there have been no efforts to model these data to date. We have compiled, curated, analyzed, and compared the available human and LLNA data. Using these data, we have developed reliable computational models and applied them for virtual screening of chemical libraries to identify putative skin sensitizers. The overall concordance between murine LLNA and human skin sensitization responses for a set of 135 unique chemicals was low (R = 28-43%), although several chemical classes had high concordance. We have succeeded to develop predictive QSAR models of all available human data with the external correct classification rate of 71%. A consensus model integrating concordant QSAR predictions and LLNA results afforded a higher CCR of 82% but at the expense of the reduced external dataset coverage (52%). We used the developed QSAR models for virtual screening of CosIng database and identified 1061 putative skin sensitizers; for seventeen of these compounds, we found published evidence of their skin sensitization effects. Models reported herein provide more accurate alternative to LLNA testing for human skin sensitization assessment across diverse chemical data. In addition, they can also be used to guide the structural optimization of toxic compounds to reduce their skin sensitization potential. PMID:28630595

  8. DigitalHuman (DH): An Integrative Mathematical Model ofHuman Physiology

    Science.gov (United States)

    Hester, Robert L.; Summers, Richard L.; lIescu, Radu; Esters, Joyee; Coleman, Thomas G.

    2010-01-01

    Mathematical models and simulation are important tools in discovering the key causal relationships governing physiological processes and improving medical intervention when physiological complexity is a central issue. We have developed a model of integrative human physiology called DigitalHuman (DH) consisting of -5000 variables modeling human physiology describing cardiovascular, renal, respiratory, endocrine, neural and metabolic physiology. Users can view time-dependent solutions and interactively introduce perturbations by altering numerical parameters to investigate new hypotheses. The variables, parameters and quantitative relationships as well as all other model details are described in XML text files. All aspects of the model, including the mathematical equations describing the physiological processes are written in XML open source, text-readable files. Model structure is based upon empirical data of physiological responses documented within the peer-reviewed literature. The model can be used to understand proposed physiological mechanisms and physiological interactions that may not be otherwise intUitively evident. Some of the current uses of this model include the analyses of renal control of blood pressure, the central role of the liver in creating and maintaining insulin resistance, and the mechanisms causing orthostatic hypotension in astronauts. Additionally the open source aspect of the modeling environment allows any investigator to add detailed descriptions of human physiology to test new concepts. The model accurately predicts both qualitative and more importantly quantitative changes in clinically and experimentally observed responses. DigitalHuman provides scientists a modeling environment to understand the complex interactions of integrative physiology. This research was supported by.NIH HL 51971, NSF EPSCoR, and NASA

  9. The relevance of non-human primate and rodent malaria models for humans

    Directory of Open Access Journals (Sweden)

    Riley Eleanor

    2011-02-01

    Full Text Available Abstract At the 2010 Keystone Symposium on "Malaria: new approaches to understanding Host-Parasite interactions", an extra scientific session to discuss animal models in malaria research was convened at the request of participants. This was prompted by the concern of investigators that skepticism in the malaria community about the use and relevance of animal models, particularly rodent models of severe malaria, has impacted on funding decisions and publication of research using animal models. Several speakers took the opportunity to demonstrate the similarities between findings in rodent models and human severe disease, as well as points of difference. The variety of malaria presentations in the different experimental models parallels the wide diversity of human malaria disease and, therefore, might be viewed as a strength. Many of the key features of human malaria can be replicated in a variety of nonhuman primate models, which are very under-utilized. The importance of animal models in the discovery of new anti-malarial drugs was emphasized. The major conclusions of the session were that experimental and human studies should be more closely linked so that they inform each other, and that there should be wider access to relevant clinical material.

  10. Modeling Human Behaviour with Higher Order Logic: Insider Threats

    DEFF Research Database (Denmark)

    Boender, Jaap; Ivanova, Marieta Georgieva; Kammuller, Florian

    2014-01-01

    it to the sociological process of logical explanation. As a case study on modeling human behaviour, we present the modeling and analysis of insider threats as a Higher Order Logic theory in Isabelle/HOL. We show how each of the three step process of sociological explanation can be seen in our modeling of insider’s state......, its context within an organisation and the effects on security as outcomes of a theorem proving analysis....

  11. Experimental Human Cell and Tissue Models of Pemphigus

    Science.gov (United States)

    van der Wier, Gerda; Pas, Hendri H.; Jonkman, Marcel F.

    2010-01-01

    Pemphigus is a chronic mucocutaneous autoimmune bullous disease that is characterized by loss of cell-cell contact in skin and/or mucous membranes. Past research has successfully identified desmosomes as immunological targets and has demonstrated that acantholysis is initiated through direct binding of IgG. The exact mechanisms of acantholysis, however, are still missing. Experimental model systems have contributed considerably to today's knowledge and are still a favourite tool of research. In this paper we will describe to what extent human cell and tissue models represent the in vivo situation, for example, organ cultures of human skin, keratinocyte cultures, and human skin grafted on mice and, furthermore, how suitable they are to study the pathogenesis of pemphigus. Organ cultures closely mimic the architecture of the epidermis but are less suitable to answer posed biochemical questions. Cultured keratinocyte monolayers are convenient in this respect, but their desmosomal make-up in terms of adhesion molecules does not exactly reflect the in vivo situation. Reconstituted skin is a relatively new model that approaches organ culture. In models of human skin grafted on mice, acantholysis can be studied in actual human skin but now with all the advantages of an animal model. PMID:20585596

  12. A Budyko-type Model for Human Water Consumption

    Science.gov (United States)

    Lei, X.; Zhao, J.; Wang, D.; Sivapalan, M.

    2017-12-01

    With the expansion of human water footprint, water crisis is no longer only a conflict or competition for water between different economic sectors, but also increasingly between human and the environment. In order to describe the emergent dynamics and patterns of the interaction, a theoretical framework that encapsulates the physical and societal controls impacting human water consumption is needed. In traditional hydrology, Budyko-type models are simple but efficient descriptions of vegetation-mediated hydrologic cycle in catchments, i.e., the partitioning of mean annual precipitation into runoff and evapotranspiration. Plant water consumption plays a crucial role in the process. Hypothesized similarities between human-water and vegetation-water interactions, including water demand, constraints and system functioning, give the idea of corresponding Budyko-type framework for human water consumption at the catchment scale. Analogous to variables of Budyko-type models for hydrologic cycle, water demand, water consumption, environmental water use and available water are corresponding to potential evaporation, actual evaporation, runoff and precipitation respectively. Human water consumption data, economic and hydro-meteorological data for 51 human-impacted catchments and 10 major river basins in China are assembled to look for the existence of a Budyko-type relationship for human water consumption, and to seek explanations for the spread in the observed relationship. Guided by this, a Budyko-type analytical model is derived based on application of an optimality principle, that of maximum water benefit. The model derived has the same functional form and mathematical features as those that apply for the original Budyko model. Parameters of the new Budyko-type model for human consumption are linked to economic and social factors. The results of this paper suggest that the functioning of both social and hydrologic subsystems within catchment systems can be explored within

  13. Non-Human Primate Models of Orthopoxvirus Infections

    Directory of Open Access Journals (Sweden)

    Anne Schmitt

    2014-06-01

    Full Text Available Smallpox, one of the most destructive diseases, has been successfully eradicated through a worldwide vaccination campaign. Since immunization programs have been stopped, the number of people with vaccinia virus induced immunity is declining. This leads to an increase in orthopoxvirus (OPXV infections in humans, as well as in animals. Additionally, potential abuse of Variola virus (VARV, the causative agent of smallpox, or monkeypox virus, as agents of bioterrorism, has renewed interest in development of antiviral therapeutics and of safer vaccines. Due to its high risk potential, research with VARV is restricted to two laboratories worldwide. Therefore, numerous animal models of other OPXV infections have been developed in the last decades. Non-human primates are especially suitable due to their close relationship to humans. This article provides a review about on non-human primate models of orthopoxvirus infections.

  14. Human airway xenograft models of epithelial cell regeneration

    Directory of Open Access Journals (Sweden)

    Puchelle Edith

    2000-10-01

    Full Text Available Abstract Regeneration and restoration of the airway epithelium after mechanical, viral or bacterial injury have a determinant role in the evolution of numerous respiratory diseases such as chronic bronchitis, asthma and cystic fibrosis. The study in vivo of epithelial regeneration in animal models has shown that airway epithelial cells are able to dedifferentiate, spread, migrate over the denuded basement membrane and progressively redifferentiate to restore a functional respiratory epithelium after several weeks. Recently, human tracheal xenografts have been developed in immunodeficient severe combined immunodeficiency (SCID and nude mice. In this review we recall that human airway cells implanted in such conditioned host grafts can regenerate a well-differentiated and functional human epithelium; we stress the interest in these humanized mice in assaying candidate progenitor and stem cells of the human airway mucosa.

  15. Human psychophysics and rodent spinal neurones exhibit peripheral and central mechanisms of inflammatory pain in the UVB and UVB heat rekindling models.

    Science.gov (United States)

    O'Neill, Jessica; Sikandar, Shafaq; McMahon, Stephen B; Dickenson, Anthony H

    2015-09-01

    Translational research is key to bridging the gaps between preclinical findings and the patients, and a translational model of inflammatory pain will ideally induce both peripheral and central sensitisation, more effectively mimicking clinical pathophysiology in some chronic inflammatory conditions. We conducted a parallel investigation of two models of inflammatory pain, using ultraviolet B (UVB) irradiation alone and UVB irradiation with heat rekindling. We used rodent electrophysiology and human quantitative sensory testing to characterise nociceptive processing in the peripheral and central nervous systems in both models. In both species, UVB irradiation produces peripheral sensitisation measured as augmented evoked activity of rat dorsal horn neurones and increased perceptual responses of human subjects to mechanical and thermal stimuli. In both species, UVB with heat rekindling produces central sensitisation. UVB irradiation alone and UVB with heat rekindling are translational models of inflammation that produce peripheral and central sensitisation, respectively. The predictive value of laboratory models for human pain processing is crucial for improving translational research. The discrepancy between peripheral and central mechanisms of pain is an important consideration for drug targets, and here we describe two models of inflammatory pain that involve ultraviolet B (UVB) irradiation, which can employ peripheral and central sensitisation to produce mechanical and thermal hyperalgesia in rats and humans. We use electrophysiology in rats to measure the mechanically- and thermally-evoked activity of rat spinal neurones and quantitative sensory testing to assess human psychophysical responses to mechanical and thermal stimulation in a model of UVB irradiation and in a model of UVB irradiation with heat rekindling. Our results demonstrate peripheral sensitisation in both species driven by UVB irradiation, with a clear mechanical and thermal hypersensitivity of

  16. Human Factor Modelling in the Risk Assessment of Port Manoeuvers

    Directory of Open Access Journals (Sweden)

    Teresa Abramowicz-Gerigk

    2015-09-01

    Full Text Available The documentation of human factor influence on the scenario development in maritime accidents compared with expert methods is commonly used as a basis in the process of setting up safety regulations and instructions. The new accidents and near misses show the necessity for further studies in determining the human factor influence on both risk acceptance criteria and development of risk control options for the manoeuvers in restricted waters. The paper presents the model of human error probability proposed for the assessment of ship masters and marine pilots' error decision and its influence on the risk of port manoeuvres.

  17. Modeling cognition dynamics and its application to human reliability analysis

    International Nuclear Information System (INIS)

    Mosleh, A.; Smidts, C.; Shen, S.H.

    1996-01-01

    For the past two decades, a number of approaches have been proposed for the identification and estimation of the likelihood of human errors, particularly for use in the risk and reliability studies of nuclear power plants. Despite the wide-spread use of the most popular among these methods, their fundamental weaknesses are widely recognized, and the treatment of human reliability has been considered as one of the soft spots of risk studies of large technological systems. To alleviate the situation, new efforts have focused on the development of human reliability models based on a more fundamental understanding of operator response and its cognitive aspects

  18. Integration of Lightning- and Human-Caused Wildfire Occurrence Models

    DEFF Research Database (Denmark)

    Vilar, Lara; Nieto Solana, Hector; Martín, M. Pilar

    2010-01-01

    Fire risk indices are useful tools for fire prevention actions by fire managers. A fire ignition is either the result of lightning or human activities. In European Mediterranean countries most forest fires are due to human activities. However, lightning is still an important fire ignition source...... probability models at 1 × 1 km grid cell resolution in two regions of Spain: Madrid, which presents a high fire incidence due to human activities; and Aragón, one of the most affected regions in Spain by lightning-fires. For validation, independent fire ignition points were used to compute the Receiver...

  19. Modeling human gastrointestinal inflammatory diseases using microphysiological culture systems.

    Science.gov (United States)

    Hartman, Kira G; Bortner, James D; Falk, Gary W; Ginsberg, Gregory G; Jhala, Nirag; Yu, Jian; Martín, Martín G; Rustgi, Anil K; Lynch, John P

    2014-09-01

    Gastrointestinal illnesses are a significant health burden for the US population, with 40 million office visits each year for gastrointestinal complaints and nearly 250,000 deaths. Acute and chronic inflammations are a common element of many gastrointestinal diseases. Inflammatory processes may be initiated by a chemical injury (acid reflux in the esophagus), an infectious agent (Helicobacter pylori infection in the stomach), autoimmune processes (graft versus host disease after bone marrow transplantation), or idiopathic (as in the case of inflammatory bowel diseases). Inflammation in these settings can contribute to acute complaints (pain, bleeding, obstruction, and diarrhea) as well as chronic sequelae including strictures and cancer. Research into the pathophysiology of these conditions has been limited by the availability of primary human tissues or appropriate animal models that attempt to physiologically model the human disease. With the many recent advances in tissue engineering and primary human cell culture systems, it is conceivable that these approaches can be adapted to develop novel human ex vivo systems that incorporate many human cell types to recapitulate in vivo growth and differentiation in inflammatory microphysiological environments. Such an advance in technology would improve our understanding of human disease progression and enhance our ability to test for disease prevention strategies and novel therapeutics. We will review current models for the inflammatory and immunological aspects of Barrett's esophagus, acute graft versus host disease, and inflammatory bowel disease and explore recent advances in culture methodologies that make these novel microphysiological research systems possible. © 2014 by the Society for Experimental Biology and Medicine.

  20. [Human resources for health in Ecuador's new model of care].

    Science.gov (United States)

    Espinosa, Verónica; de la Torre, Daniel; Acuña, Cecilia; Cadena, Cristina

    2017-06-08

    Describe strategies implemented by Ecuador's Ministry of Public Health (MPH) to strengthen human resources for health leadership and respond to the new model of care, as a part of the reform process in the period 2012-2015. A documentary review was carried out of primary and secondary sources on development of human resources for health before and after the reform. In the study period, Ecuador developed a new institutional and regulatory framework for developing human resources for health to respond to the requirements of a model of care based on primary health care. The MPH consolidated its steering role by forging strategic partnerships, implementing human resources planning methods, and making an unprecedented investment in health worker training, hiring, and wage increases. These elements constitute the initial core for development of human resources for health policy and a health-services study program consistent with the reform's objectives. Within the framework of the reform carried out from 2012 to 2015, intersectoral work by the MPH has led to considerable achievements in development of human resources for health. Notable achievements include strengthening of the steering role, development and implementation of standards and regulatory instruments, creation of new professional profiles, and hiring of professionals to implement the comprehensive health care model, which helped to solve problems carried over from the years prior to the reform.

  1. Human performance modeling for system of systems analytics :soldier fatigue.

    Energy Technology Data Exchange (ETDEWEB)

    Lawton, Craig R.; Campbell, James E.; Miller, Dwight Peter

    2005-10-01

    The military has identified Human Performance Modeling (HPM) as a significant requirement and challenge of future systems modeling and analysis initiatives as can be seen in the Department of Defense's (DoD) Defense Modeling and Simulation Office's (DMSO) Master Plan (DoD 5000.59-P 1995). To this goal, the military is currently spending millions of dollars on programs devoted to HPM in various military contexts. Examples include the Human Performance Modeling Integration (HPMI) program within the Air Force Research Laboratory, which focuses on integrating HPMs with constructive models of systems (e.g. cockpit simulations) and the Navy's Human Performance Center (HPC) established in September 2003. Nearly all of these initiatives focus on the interface between humans and a single system. This is insufficient in the era of highly complex network centric SoS. This report presents research and development in the area of HPM in a system-of-systems (SoS). Specifically, this report addresses modeling soldier fatigue and the potential impacts soldier fatigue can have on SoS performance.

  2. Chimeric animal models in human stem cell biology.

    Science.gov (United States)

    Glover, Joel C; Boulland, Jean-Luc; Halasi, Gabor; Kasumacic, Nedim

    2009-01-01

    The clinical use of stem cells for regenerative medicine is critically dependent on preclinical studies in animal models. In this review we examine some of the key issues and challenges in the use of animal models to study human stem cell biology-experimental standardization, body size, immunological barriers, cell survival factors, fusion of host and donor cells, and in vivo imaging and tracking. We focus particular attention on the various imaging modalities that can be used to track cells in living animals, comparing their strengths and weaknesses and describing technical developments that are likely to lead to new opportunities for the dynamic assessment of stem cell behavior in vivo. We then provide an overview of some of the most commonly used animal models, their advantages and disadvantages, and examples of their use for xenotypic transplantation of human stem cells, with separate reviews of models involving rodents, ungulates, nonhuman primates, and the chicken embryo. As the use of human somatic, embryonic, and induced pluripotent stem cells increases, so too will the range of applications for these animal models. It is likely that increasingly sophisticated uses of human/animal chimeric models will be developed through advances in genetic manipulation, cell delivery, and in vivo imaging.

  3. Improving Saliency Models by Predicting Human Fixation Patches

    KAUST Repository

    Dubey, Rachit

    2015-04-16

    There is growing interest in studying the Human Visual System (HVS) to supplement and improve the performance of computer vision tasks. A major challenge for current visual saliency models is predicting saliency in cluttered scenes (i.e. high false positive rate). In this paper, we propose a fixation patch detector that predicts image patches that contain human fixations with high probability. Our proposed model detects sparse fixation patches with an accuracy of 84 % and eliminates non-fixation patches with an accuracy of 84 % demonstrating that low-level image features can indeed be used to short-list and identify human fixation patches. We then show how these detected fixation patches can be used as saliency priors for popular saliency models, thus, reducing false positives while maintaining true positives. Extensive experimental results show that our proposed approach allows state-of-the-art saliency methods to achieve better prediction performance on benchmark datasets.

  4. Improving Saliency Models by Predicting Human Fixation Patches

    KAUST Repository

    Dubey, Rachit; Dave, Akshat; Ghanem, Bernard

    2015-01-01

    There is growing interest in studying the Human Visual System (HVS) to supplement and improve the performance of computer vision tasks. A major challenge for current visual saliency models is predicting saliency in cluttered scenes (i.e. high false positive rate). In this paper, we propose a fixation patch detector that predicts image patches that contain human fixations with high probability. Our proposed model detects sparse fixation patches with an accuracy of 84 % and eliminates non-fixation patches with an accuracy of 84 % demonstrating that low-level image features can indeed be used to short-list and identify human fixation patches. We then show how these detected fixation patches can be used as saliency priors for popular saliency models, thus, reducing false positives while maintaining true positives. Extensive experimental results show that our proposed approach allows state-of-the-art saliency methods to achieve better prediction performance on benchmark datasets.

  5. A Novel Porcine Model of Septic Shock Induced by Acute Respiratory Distress Syndrome due to Methicillin-resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Shuo Wang

    2017-01-01

    Conclusions: In the present study, we developed a novel porcine model of septic shock induced by ARDS due to severe MRSA pneumonia with characteristic hyperdynamic and hypodynamic phases in 24 h, which mimicked the hemodynamic changing of septic shock in human.

  6. Genetic engineering in nonhuman primates for human disease modeling.

    Science.gov (United States)

    Sato, Kenya; Sasaki, Erika

    2018-02-01

    Nonhuman primate (NHP) experimental models have contributed greatly to human health research by assessing the safety and efficacy of newly developed drugs, due to their physiological and anatomical similarities to humans. To generate NHP disease models, drug-inducible methods, and surgical treatment methods have been employed. Recent developments in genetic and developmental engineering in NHPs offer new options for producing genetically modified disease models. Moreover, in recent years, genome-editing technology has emerged to further promote this trend and the generation of disease model NHPs has entered a new era. In this review, we summarize the generation of conventional disease model NHPs and discuss new solutions to the problem of mosaicism in genome-editing technology.

  7. Simulation Models of Human Decision-Making Processes

    Directory of Open Access Journals (Sweden)

    Nina RIZUN

    2014-10-01

    Full Text Available The main purpose of the paper is presentation of the new concept of human decision-making process modeling via using the analogy with Automatic Control Theory. From the author's point of view this concept allows to develop and improve the theory of decision-making in terms of the study and classification of specificity of the human intellectual processes in different conditions. It was proved that the main distinguishing feature between the Heuristic / Intuitive and Rational Decision-Making Models is the presence of so-called phenomenon of "enrichment" of the input information with human propensity, hobbies, tendencies, expectations, axioms and judgments, presumptions or bias and their justification. In order to obtain additional knowledge about the basic intellectual processes as well as the possibility of modeling the decision results in various parameters characterizing the decision-maker, the complex of the simulation models was developed. These models are based on the assumptions that:  basic intellectual processes of the Rational Decision-Making Model can be adequately simulated and identified by the transient processes of the proportional-integral-derivative controller; basic intellectual processes of the Bounded Rationality and Intuitive Models can be adequately simulated and identified by the transient processes of the nonlinear elements.The taxonomy of the most typical automatic control theory elements and their compliance with certain decision-making models with a point of view of decision-making process specificity and decision-maker behavior during a certain time of professional activity was obtained.

  8. Geometric Modeling and Reasoning of Human-Centered Freeform Products

    CERN Document Server

    Wang, Charlie C L

    2013-01-01

    The recent trend in user-customized product design requires the shape of products to be automatically adjusted according to the human body’s shape, so that people will feel more comfortable when wearing these products.  Geometric approaches can be used to design the freeform shape of products worn by people, which can greatly improve the efficiency of design processes in various industries involving customized products (e.g., garment design, toy design, jewel design, shoe design, and design of medical devices, etc.). These products are usually composed of very complex geometric shapes (represented by free-form surfaces), and are not driven by a parameter table but a digital human model with free-form shapes or part of human bodies (e.g., wrist, foot, and head models).   Geometric Modeling and Reasoning of Human-Centered Freeform Products introduces the algorithms of human body reconstruction, freeform product modeling, constraining and reconstructing freeform products, and shape optimization for improving...

  9. Human, Social, Cultural Behavior (HSCB) Modeling Workshop I: Characterizing the Capability Needs for HSCB Modeling

    Science.gov (United States)

    2008-07-01

    The expectations correspond to different roles individuals perform SocialConstructionis Social constructionism is a school of thought Peter L...HUMAN, SOCIAL , CULTURAL BEHAVIOR (HSCB) MODELING WORKSHOP I: CHARACTERIZING THE CAPABILITY NEEDS FOR HSCB MODELING FINAL REPORT... Social , Cultural Behavior (HSCB) Modeling Workshop I: Characterizing the Capability Needs for HSCB Modeling 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  10. Material Models for the Human Torso Finite Element Model

    Science.gov (United States)

    2018-04-04

    44-mm standard for body armors required ballistic tests of armor backed by Roma Plastilina clay . The scope has expanded to include hard armors as...conditions were not fully considered, and that the connections between the clay -backed deflections and goat lethality were preliminary results... viscosity component needed to represent organic tissue in the Mat77 material model. Material characterizations from the published literature were drawn

  11. Elucidation of xenobiotic metabolism pathways in human skin and human skin models by proteomic profiling.

    Directory of Open Access Journals (Sweden)

    Sven van Eijl

    Full Text Available BACKGROUND: Human skin has the capacity to metabolise foreign chemicals (xenobiotics, but knowledge of the various enzymes involved is incomplete. A broad-based unbiased proteomics approach was used to describe the profile of xenobiotic metabolising enzymes present in human skin and hence indicate principal routes of metabolism of xenobiotic compounds. Several in vitro models of human skin have been developed for the purpose of safety assessment of chemicals. The suitability of these epidermal models for studies involving biotransformation was assessed by comparing their profiles of xenobiotic metabolising enzymes with those of human skin. METHODOLOGY/PRINCIPAL FINDINGS: Label-free proteomic analysis of whole human skin (10 donors was applied and analysed using custom-built PROTSIFT software. The results showed the presence of enzymes with a capacity for the metabolism of alcohols through dehydrogenation, aldehydes through dehydrogenation and oxidation, amines through oxidation, carbonyls through reduction, epoxides and carboxylesters through hydrolysis and, of many compounds, by conjugation to glutathione. Whereas protein levels of these enzymes in skin were mostly just 4-10 fold lower than those in liver and sufficient to support metabolism, the levels of cytochrome P450 enzymes were at least 300-fold lower indicating they play no significant role. Four epidermal models of human skin had profiles very similar to one another and these overlapped substantially with that of whole skin. CONCLUSIONS/SIGNIFICANCE: The proteomics profiling approach was successful in producing a comprehensive analysis of the biotransformation characteristics of whole human skin and various in vitro skin models. The results show that skin contains a range of defined enzymes capable of metabolising different classes of chemicals. The degree of similarity of the profiles of the in vitro models indicates their suitability for epidermal toxicity testing. Overall, these

  12. Human pluripotent stem cells in modeling human disorders: the case of fragile X syndrome.

    Science.gov (United States)

    Vershkov, Dan; Benvenisty, Nissim

    2017-01-01

    Human pluripotent stem cells (PSCs) generated from affected blastocysts or from patient-derived somatic cells are an emerging platform for disease modeling and drug discovery. Fragile X syndrome (FXS), the leading cause of inherited intellectual disability, was one of the first disorders modeled in both embryonic stem cells and induced PCSs and can serve as an exemplary case for the utilization of human PSCs in the study of human diseases. Over the past decade, FXS-PSCs have been used to address the fundamental questions regarding the pathophysiology of FXS. In this review we summarize the methodologies for generation of FXS-PSCs, discuss their advantages and disadvantages compared with existing modeling systems and describe their utilization in the study of FXS pathogenesis and in the development of targeted treatment.

  13. Cognitive modelling: a basic complement of human reliability analysis

    International Nuclear Information System (INIS)

    Bersini, U.; Cacciabue, P.C.; Mancini, G.

    1988-01-01

    In this paper the issues identified in modelling humans and machines are discussed in the perspective of the consideration of human errors managing complex plants during incidental as well as normal conditions. The dichotomy between the use of a cognitive versus a behaviouristic model approach is discussed and the complementarity aspects rather than the differences of the two methods are identified. A cognitive model based on a hierarchical goal-oriented approach and driven by fuzzy logic methodology is presented as the counterpart to the 'classical' THERP methodology for studying human errors. Such a cognitive model is discussed at length and its fundamental components, i.e. the High Level Decision Making and the Low Level Decision Making models, are reviewed. Finally, the inadequacy of the 'classical' THERP methodology to deal with cognitive errors is discussed on the basis of a simple test case. For the same case the cognitive model is then applied showing the flexibility and adequacy of the model to dynamic configuration with time-dependent failures of components and with consequent need for changing of strategy during the transient itself. (author)

  14. Coupling of the Models of Human Physiology and Thermal Comfort

    Science.gov (United States)

    Pokorny, J.; Jicha, M.

    2013-04-01

    A coupled model of human physiology and thermal comfort was developed in Dymola/Modelica. A coupling combines a modified Tanabe model of human physiology and thermal comfort model developed by Zhang. The Coupled model allows predicting the thermal sensation and comfort of both local and overall from local boundary conditions representing ambient and personal factors. The aim of this study was to compare prediction of the Coupled model with the Fiala model prediction and experimental data. Validation data were taken from the literature, mainly from the validation manual of software Theseus-FE [1]. In the paper validation of the model for very light physical activities (1 met) indoor environment with temperatures from 12 °C up to 48 °C is presented. The Coupled model predicts mean skin temperature for cold, neutral and warm environment well. However prediction of core temperature in cold environment is inaccurate and very affected by ambient temperature. Evaluation of thermal comfort in warm environment is supplemented by skin wettedness prediction. The Coupled model is designed for non-uniform and transient environmental conditions; it is also suitable simulation of thermal comfort in vehicles cabins. The usage of the model is limited for very light physical activities up to 1.2 met only.

  15. Coupling of the Models of Human Physiology and Thermal Comfort

    Directory of Open Access Journals (Sweden)

    Jicha M.

    2013-04-01

    Full Text Available A coupled model of human physiology and thermal comfort was developed in Dymola/Modelica. A coupling combines a modified Tanabe model of human physiology and thermal comfort model developed by Zhang. The Coupled model allows predicting the thermal sensation and comfort of both local and overall from local boundary conditions representing ambient and personal factors. The aim of this study was to compare prediction of the Coupled model with the Fiala model prediction and experimental data. Validation data were taken from the literature, mainly from the validation manual of software Theseus–FE [1]. In the paper validation of the model for very light physical activities (1 met indoor environment with temperatures from 12 °C up to 48 °C is presented. The Coupled model predicts mean skin temperature for cold, neutral and warm environment well. However prediction of core temperature in cold environment is inaccurate and very affected by ambient temperature. Evaluation of thermal comfort in warm environment is supplemented by skin wettedness prediction. The Coupled model is designed for non-uniform and transient environmental conditions; it is also suitable simulation of thermal comfort in vehicles cabins. The usage of the model is limited for very light physical activities up to 1.2 met only.

  16. Endometriosis of the mesoappendix mimicking appendicitis: A case report

    Directory of Open Access Journals (Sweden)

    Suman Mewa Kinoo

    2016-09-01

    Full Text Available Although appendicitis is largely a clinical diagnosis, on occasions diagnostic modalities may be needed to aid with the diagnosis. Despite the use of adjuncts and exploratory surgery, the diagnosis may not be clear until a histological diagnosis is achieved. Endometriosis of the appendix mimicking appendicitis is one of these diagnoses described in several case reports. Endometriosis of the meso-appendix has been described in association with intussusception of the appendix in several case reports. However, to our knowledge, endometriosis of the meso-appendix mimicking appendicitis has not been reported to date. We present the case of a 33-year-old woman with classic clinical signs and symptoms of appendicitis endorsed on computed tomography imaging. The patient underwent a laparoscopic appendicectomy with the postoperative histology demonstrating a normal appendix with endometriosis of the meso-appendix.

  17. Rare extraskeletal Ewing's sarcoma mimicking as adenocarcinoma of the sigmoid.

    Science.gov (United States)

    Mertens, Michelle; Haenen, Filip W N; Siozopoulou, Vasiliki; Van Cleemput, Marc

    2017-06-01

    Extraskeletal Ewing's sarcoma (EES) is a rare finding in comparison with Ewing's sarcoma of bone and usually manifests in young patients. However, even in older patients, one must consider the diagnosis. In this case, we describe a 52-year-old woman diagnosed with EES, mimicking as adenocarcinoma of the sigmoid. The tumor was not visualized by a multi-slice spiral computed tomography of the abdomen and pelvis with intravenous contrast, and eventually the diagnosis was made by positive immunohistochemical staining for CD99 and by molecular testing for EWSR1 translocation. This combination of the patient's age and the localization of the tumor mimicking an adenocarcinoma of the sigmoid has never been described before.

  18. A dystrophic Duchenne mouse model for testing human antisense oligonucleotides.

    Directory of Open Access Journals (Sweden)

    Marcel Veltrop

    Full Text Available Duchenne muscular dystrophy (DMD is a severe muscle-wasting disease generally caused by reading frame disrupting mutations in the DMD gene resulting in loss of functional dystrophin protein. The reading frame can be restored by antisense oligonucleotide (AON-mediated exon skipping, allowing production of internally deleted, but partially functional dystrophin proteins as found in the less severe Becker muscular dystrophy. Due to genetic variation between species, mouse models with mutations in the murine genes are of limited use to test and further optimize human specific AONs in vivo. To address this we have generated the del52hDMD/mdx mouse. This model carries both murine and human DMD genes. However, mouse dystrophin expression is abolished due to a stop mutation in exon 23, while the expression of human dystrophin is abolished due to a deletion of exon 52. The del52hDMD/mdx model, like mdx, shows signs of muscle dystrophy on a histological level and phenotypically mild functional impairment. Local administration of human specific vivo morpholinos induces exon skipping and dystrophin restoration in these mice. Depending on the number of mismatches, occasional skipping of the murine Dmd gene, albeit at low levels, could be observed. Unlike previous models, the del52hDMD/mdx model enables the in vivo analysis of human specific AONs targeting exon 51 or exon 53 on RNA and protein level and muscle quality and function. Therefore, it will be a valuable tool for optimizing human specific AONs and genome editing approaches for DMD.

  19. More-Realistic Digital Modeling of a Human Body

    Science.gov (United States)

    Rogge, Renee

    2010-01-01

    A MATLAB computer program has been written to enable improved (relative to an older program) modeling of a human body for purposes of designing space suits and other hardware with which an astronaut must interact. The older program implements a kinematic model based on traditional anthropometric measurements that do provide important volume and surface information. The present program generates a three-dimensional (3D) whole-body model from 3D body-scan data. The program utilizes thin-plate spline theory to reposition the model without need for additional scans.

  20. Degenerated uterine leiomyomas mimicking malignant bilateral ovarian surface epithelial tumors

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Yi Boem Ha; Lee, Hae Kyung; Lee, Min Hee; Choi, Seo Youn; Chung, Soo Ho [Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of)

    2017-07-15

    Uterine leiomyomas are the most common benign uterine neoplasms. Undegenerated uterine leiomyomas are easily recognizable by the typical imaging findings on radiologic studies. However, degenerated fibroids can have unusual and variable appearances. The atypical appearances due to degenerative changes may cause confusion in diagnosis of leiomyomas. In this article, we report a case of a patient with extensive cystic and myxoid degeneration of uterine leiomyoma, mimicking malignant bilateral ovarian surface epithelial tumors.

  1. Addison's Disease Mimicking as Acute Pancreatitis: A Case Report.

    Science.gov (United States)

    Chaudhuri, Sayani; Rao, Karthik N; Patil, Navin; Ommurugan, Balaji; Varghese, George

    2017-04-01

    Over past two decades there has been significant improvement in medical field in elucidating the underlying pathophysiology and genetics of Addison's disease. Adrenal insufficiency (Addison's disease) is a rare disease with an incidence of 0.8/100,000 cases. The diagnosis may be delayed if the clinical presentation mimics a gastrointestinal disorder or psychiatric illness. We report a case of Addison's disease presenting as acute pain in abdomen mimicking clinical presentation of acute pancreatitis.

  2. An abdominal tuberculosis case mimicking an abdominal mass

    African Journals Online (AJOL)

    An abdominal tuberculosis case mimicking an abdominal mass. Derya Erdog˘ an a. , Yasemin Ta ¸scı Yıldız b. , Esin Cengiz Bodurog˘lu c and Naciye Go¨nu¨l Tanır d. Abdominal tuberculosis is rare in childhood. It may be difficult to diagnose as it mimics various disorders. We present a 12-year-old child with an unusual ...

  3. A case of gallbladder mass: Malakoplakia (The tumor mimicker

    Directory of Open Access Journals (Sweden)

    Kanwaljeet Singh

    2017-01-01

    Full Text Available Diagnosis of malakoplakia presenting as gall bladder mass is a diagnostic dilemma faced by pathologists, radiologists, and surgeons. Malakoplakia is a rare inflammatory disorder and tumor mimicker usually occurring in the urinary tract, may occasionally be found in gall bladder. Here, we present a rare case, presenting as gall bladder mass in a known case of gallstone disease, clinically suspected as carcinoma and later turned out to be malakoplakia in gall bladder.

  4. Investigation and Modeling of Capacitive Human Body Communication.

    Science.gov (United States)

    Zhu, Xiao-Qi; Guo, Yong-Xin; Wu, Wen

    2017-04-01

    This paper presents a systematic investigation of the capacitive human body communication (HBC). The measurement of HBC channels is performed using a novel battery-powered system to eliminate the effects of baluns, cables and instruments. To verify the measured results, a numerical model incorporating the entire HBC system is established. Besides, it is demonstrated that both the impedance and path gain bandwidths of HBC channels is affected by the electrode configuration. Based on the analysis of the simulated electric field distribution, an equivalent circuit model is proposed and the circuit parameters are extracted using the finite element method. The transmission capability along the human body is also studied. The simulated results using the numerical and circuit models coincide very well with the measurement, which demonstrates that the proposed circuit model can effectively interpret the operation mechanism of the capacitive HBC.

  5. Mechanics, Mechanobiology, and Modeling of Human Abdominal Aorta and Aneurysms

    Science.gov (United States)

    Humphrey, J.D.; Holzapfel, G.A.

    2011-01-01

    Biomechanical factors play fundamental roles in the natural history of abdominal aortic aneurysms (AAAs) and their responses to treatment. Advances during the past two decades have increased our understanding of the mechanics and biology of the human abdominal aorta and AAAs, yet there remains a pressing need for considerable new data and resulting patient-specific computational models that can better describe the current status of a lesion and better predict the evolution of lesion geometry, composition, and material properties and thereby improve interventional planning. In this paper, we briefly review data on the structure and function of the human abdominal aorta and aneurysmal wall, past models of the mechanics, and recent growth and remodeling models. We conclude by identifying open problems that we hope will motivate studies to improve our computational modeling and thus general understanding of AAAs. PMID:22189249

  6. Animation of 3D Model of Human Head

    Directory of Open Access Journals (Sweden)

    V. Michalcin

    2007-04-01

    Full Text Available The paper deals with the new algorithm of animation of 3D model of the human head in combination with its global motion. The designed algorithm is very fast and with low calculation requirements, because it does not need the synthesis of the input videosequence for estimation of the animation parameters as well as the parameters of global motion. The used 3D model Candide generates different expressions using its animation units which are controlled by the animation parameters. These ones are estimated on the basis of optical flow without the need of extracting of the feature points in the frames of the input videosequence because they are given by the selected vertices of the animation units of the calibrated 3D model Candide. The established multiple iterations inside the designed animation algorithm of 3D model of the human head between two successive frames significantly improved its accuracy above all for the large motion.

  7. A Multiscale Survival Process for Modeling Human Activity Patterns.

    Science.gov (United States)

    Zhang, Tianyang; Cui, Peng; Song, Chaoming; Zhu, Wenwu; Yang, Shiqiang

    2016-01-01

    Human activity plays a central role in understanding large-scale social dynamics. It is well documented that individual activity pattern follows bursty dynamics characterized by heavy-tailed interevent time distributions. Here we study a large-scale online chatting dataset consisting of 5,549,570 users, finding that individual activity pattern varies with timescales whereas existing models only approximate empirical observations within a limited timescale. We propose a novel approach that models the intensity rate of an individual triggering an activity. We demonstrate that the model precisely captures corresponding human dynamics across multiple timescales over five orders of magnitudes. Our model also allows extracting the population heterogeneity of activity patterns, characterized by a set of individual-specific ingredients. Integrating our approach with social interactions leads to a wide range of implications.

  8. Tracking Human Immunodeficiency Virus-1 Infection in the Humanized DRAG Mouse Model

    Science.gov (United States)

    Kim, Jiae; Peachman, Kristina K.; Jobe, Ousman; Morrison, Elaine B.; Allam, Atef; Jagodzinski, Linda; Casares, Sofia A.; Rao, Mangala

    2017-01-01

    Humanized mice are emerging as an alternative model system to well-established non-human primate (NHP) models for studying human immunodeficiency virus (HIV)-1 biology and pathogenesis. Although both NHP and humanized mice have their own strengths and could never truly reflect the complex human immune system and biology, there are several advantages of using the humanized mice in terms of using primary HIV-1 for infection instead of simian immunodeficiency virus or chimera simian/HIV. Several different types of humanized mice have been developed with varying levels of reconstitution of human CD45+ cells. In this study, we utilized humanized Rag1KO.IL2RγcKO.NOD mice expressing HLA class II (DR4) molecule (DRAG mice) infused with HLA-matched hematopoietic stem cells from umbilical cord blood to study early events after HIV-1 infection, since the mucosal tissues of these mice are highly enriched for human lymphocytes and express the receptors and coreceptors needed for HIV-1 entry. We examined the various tissues on days 4, 7, 14, and 21 after an intravaginal administration of a single dose of purified primary HIV-1. Plasma HIV-1 RNA was detected as early as day 7, with 100% of the animals becoming plasma RNA positive by day 21 post-infection. Single cells were isolated from lymph nodes, bone marrow, spleen, gut, female reproductive tissue, and brain and analyzed for gag RNA and strong stop DNA by quantitative (RT)-PCR. Our data demonstrated the presence of HIV-1 viral RNA and DNA in all of the tissues examined and that the virus was replication competent and spread rapidly. Bone marrow, gut, and lymph nodes were viral RNA positive by day 4 post-infection, while other tissues and plasma became positive typically between 7 and 14 days post-infection. Interestingly, the brain was the last tissue to become HIV-1 viral RNA and DNA positive by day 21 post-infection. These data support the notion that humanized DRAG mice could serve as an excellent model for studying the

  9. Tracking Human Immunodeficiency Virus-1 Infection in the Humanized DRAG Mouse Model

    Directory of Open Access Journals (Sweden)

    Jiae Kim

    2017-10-01

    Full Text Available Humanized mice are emerging as an alternative model system to well-established non-human primate (NHP models for studying human immunodeficiency virus (HIV-1 biology and pathogenesis. Although both NHP and humanized mice have their own strengths and could never truly reflect the complex human immune system and biology, there are several advantages of using the humanized mice in terms of using primary HIV-1 for infection instead of simian immunodeficiency virus or chimera simian/HIV. Several different types of humanized mice have been developed with varying levels of reconstitution of human CD45+ cells. In this study, we utilized humanized Rag1KO.IL2RγcKO.NOD mice expressing HLA class II (DR4 molecule (DRAG mice infused with HLA-matched hematopoietic stem cells from umbilical cord blood to study early events after HIV-1 infection, since the mucosal tissues of these mice are highly enriched for human lymphocytes and express the receptors and coreceptors needed for HIV-1 entry. We examined the various tissues on days 4, 7, 14, and 21 after an intravaginal administration of a single dose of purified primary HIV-1. Plasma HIV-1 RNA was detected as early as day 7, with 100% of the animals becoming plasma RNA positive by day 21 post-infection. Single cells were isolated from lymph nodes, bone marrow, spleen, gut, female reproductive tissue, and brain and analyzed for gag RNA and strong stop DNA by quantitative (RT-PCR. Our data demonstrated the presence of HIV-1 viral RNA and DNA in all of the tissues examined and that the virus was replication competent and spread rapidly. Bone marrow, gut, and lymph nodes were viral RNA positive by day 4 post-infection, while other tissues and plasma became positive typically between 7 and 14 days post-infection. Interestingly, the brain was the last tissue to become HIV-1 viral RNA and DNA positive by day 21 post-infection. These data support the notion that humanized DRAG mice could serve as an excellent model

  10. Human Posture and Movement Prediction based on Musculoskeletal Modeling

    DEFF Research Database (Denmark)

    Farahani, Saeed Davoudabadi

    2014-01-01

    Abstract This thesis explores an optimization-based formulation, so-called inverse-inverse dynamics, for the prediction of human posture and motion dynamics performing various tasks. It is explained how this technique enables us to predict natural kinematic and kinetic patterns for human posture...... and motion using AnyBody Modeling System (AMS). AMS uses inverse dynamics to analyze musculoskeletal systems and is, therefore, limited by its dependency on input kinematics. We propose to alleviate this dependency by assuming that voluntary postures and movement strategies in humans are guided by a desire...... expenditure, joint forces and other physiological properties derived from the detailed musculoskeletal analysis. Several attempts have been made to uncover the principles underlying motion control strategies in the literature. In case of some movements, like human squat jumping, there is almost no doubt...

  11. Cognitive Emotional Regulation Model in Human-Robot Interaction

    OpenAIRE

    Liu, Xin; Xie, Lun; Liu, Anqi; Li, Dan

    2015-01-01

    This paper integrated Gross cognitive process into the HMM (hidden Markov model) emotional regulation method and implemented human-robot emotional interaction with facial expressions and behaviors. Here, energy was the psychological driving force of emotional transition in the cognitive emotional model. The input facial expression was translated into external energy by expression-emotion mapping. Robot’s next emotional state was determined by the cognitive energy (the stimulus after cognition...

  12. Science-Based Simulation Model of Human Performance for Human Reliability Analysis

    International Nuclear Information System (INIS)

    Kelly, Dana L.; Boring, Ronald L.; Mosleh, Ali; Smidts, Carol

    2011-01-01

    Human reliability analysis (HRA), a component of an integrated probabilistic risk assessment (PRA), is the means by which the human contribution to risk is assessed, both qualitatively and quantitatively. However, among the literally dozens of HRA methods that have been developed, most cannot fully model and quantify the types of errors that occurred at Three Mile Island. Furthermore, all of the methods lack a solid empirical basis, relying heavily on expert judgment or empirical results derived in non-reactor domains. Finally, all of the methods are essentially static, and are thus unable to capture the dynamics of an accident in progress. The objective of this work is to begin exploring a dynamic simulation approach to HRA, one whose models have a basis in psychological theories of human performance, and whose quantitative estimates have an empirical basis. This paper highlights a plan to formalize collaboration among the Idaho National Laboratory (INL), the University of Maryland, and The Ohio State University (OSU) to continue development of a simulation model initially formulated at the University of Maryland. Initial work will focus on enhancing the underlying human performance models with the most recent psychological research, and on planning follow-on studies to establish an empirical basis for the model, based on simulator experiments to be carried out at the INL and at the OSU.

  13. Mathematical models of human cerebellar development in the fetal period.

    Science.gov (United States)

    Dudek, Krzysztof; Nowakowska-Kotas, Marta; Kędzia, Alicja

    2018-04-01

    The evaluation of cerebellar growth in the fetal period forms a part of a widely used examination to identify any features of abnormalities in early stages of human development. It is well known that the development of anatomical structures, including the cerebellum, does not always follow a linear model of growth. The aim of the study was to analyse a variety of mathematical models of human cerebellar development in fetal life to determine their adequacy. The study comprised 101 fetuses (48 males and 53 females) between the 15th and 28th weeks of fetal life. The cerebellum was exposed and measurements of the vermis and hemispheres were performed, together with statistical analyses. The mathematical model parameters of fetal growth were assessed for crown-rump length (CRL) increases, transverse cerebellar diameter and ventrodorsal dimensions of the cerebellar vermis in the transverse plane, and rostrocaudal dimensions of the cerebellar vermis and hemispheres in the frontal plane. A variety of mathematical models were applied, including linear and non-linear functions. Taking into consideration the variance between models and measurements, as well as correlation parameters, the exponential and Gompertz models proved to be the most suitable for modelling cerebellar growth in the second and third trimesters of pregnancy. However, the linear model gave a satisfactory approximation of cerebellar growth, especially in older fetuses. The proposed models of fetal cerebellar growth constructed on the basis of anatomical examination and objective mathematical calculations could be useful in the estimation of fetal development. © 2018 Anatomical Society.

  14. Fractional calculus model of electrical impedance applied to human skin.

    Science.gov (United States)

    Vosika, Zoran B; Lazovic, Goran M; Misevic, Gradimir N; Simic-Krstic, Jovana B

    2013-01-01

    Fractional calculus is a mathematical approach dealing with derivatives and integrals of arbitrary and complex orders. Therefore, it adds a new dimension to understand and describe basic nature and behavior of complex systems in an improved way. Here we use the fractional calculus for modeling electrical properties of biological systems. We derived a new class of generalized models for electrical impedance and applied them to human skin by experimental data fitting. The primary model introduces new generalizations of: 1) Weyl fractional derivative operator, 2) Cole equation, and 3) Constant Phase Element (CPE). These generalizations were described by the novel equation which presented parameter [Formula: see text] related to remnant memory and corrected four essential parameters [Formula: see text] We further generalized single generalized element by introducing specific partial sum of Maclaurin series determined by parameters [Formula: see text] We defined individual primary model elements and their serial combination models by the appropriate equations and electrical schemes. Cole equation is a special case of our generalized class of models for[Formula: see text] Previous bioimpedance data analyses of living systems using basic Cole and serial Cole models show significant imprecisions. Our new class of models considerably improves the quality of fitting, evaluated by mean square errors, for bioimpedance data obtained from human skin. Our models with new parameters presented in specific partial sum of Maclaurin series also extend representation, understanding and description of complex systems electrical properties in terms of remnant memory effects.

  15. Fractional calculus model of electrical impedance applied to human skin.

    Directory of Open Access Journals (Sweden)

    Zoran B Vosika

    Full Text Available Fractional calculus is a mathematical approach dealing with derivatives and integrals of arbitrary and complex orders. Therefore, it adds a new dimension to understand and describe basic nature and behavior of complex systems in an improved way. Here we use the fractional calculus for modeling electrical properties of biological systems. We derived a new class of generalized models for electrical impedance and applied them to human skin by experimental data fitting. The primary model introduces new generalizations of: 1 Weyl fractional derivative operator, 2 Cole equation, and 3 Constant Phase Element (CPE. These generalizations were described by the novel equation which presented parameter [Formula: see text] related to remnant memory and corrected four essential parameters [Formula: see text] We further generalized single generalized element by introducing specific partial sum of Maclaurin series determined by parameters [Formula: see text] We defined individual primary model elements and their serial combination models by the appropriate equations and electrical schemes. Cole equation is a special case of our generalized class of models for[Formula: see text] Previous bioimpedance data analyses of living systems using basic Cole and serial Cole models show significant imprecisions. Our new class of models considerably improves the quality of fitting, evaluated by mean square errors, for bioimpedance data obtained from human skin. Our models with new parameters presented in specific partial sum of Maclaurin series also extend representation, understanding and description of complex systems electrical properties in terms of remnant memory effects.

  16. Human-centric decision-making models for social sciences

    CERN Document Server

    Pedrycz, Witold

    2014-01-01

    The volume delivers a wealth of effective methods to deal with various types of uncertainty inherently existing in human-centric decision problems. It elaborates on  comprehensive decision frameworks to handle different decision scenarios, which help use effectively the explicit and tacit knowledge and intuition, model perceptions and preferences in a more human-oriented style. The book presents original approaches and delivers new results on fundamentals and applications related to human-centered decision making approaches to business, economics and social systems. Individual chapters cover multi-criteria (multiattribute) decision making, decision making with prospect theory, decision making with incomplete probabilistic information, granular models of decision making and decision making realized with the use of non-additive measures. New emerging decision theories being presented as along with a wide spectrum of ongoing research make the book valuable to all interested in the field of advanced decision-mak...

  17. Electromagnetic Modeling of Human Body Using High Performance Computing

    Science.gov (United States)

    Ng, Cho-Kuen; Beall, Mark; Ge, Lixin; Kim, Sanghoek; Klaas, Ottmar; Poon, Ada

    Realistic simulation of electromagnetic wave propagation in the actual human body can expedite the investigation of the phenomenon of harvesting implanted devices using wireless powering coupled from external sources. The parallel electromagnetics code suite ACE3P developed at SLAC National Accelerator Laboratory is based on the finite element method for high fidelity accelerator simulation, which can be enhanced to model electromagnetic wave propagation in the human body. Starting with a CAD model of a human phantom that is characterized by a number of tissues, a finite element mesh representing the complex geometries of the individual tissues is built for simulation. Employing an optimal power source with a specific pattern of field distribution, the propagation and focusing of electromagnetic waves in the phantom has been demonstrated. Substantial speedup of the simulation is achieved by using multiple compute cores on supercomputers.

  18. Nonnecrotizing anterior scleritis mimicking orbital inflammatory disease

    Directory of Open Access Journals (Sweden)

    Lynch MC

    2013-08-01

    Full Text Available Michelle Chen Lynch,1 Andrew B Mick21Optometry Clinic, Ocala West Veterans Affairs Specialty Clinic, Ocala, FL, USA; 2Eye Clinic, San Francisco VA Medical Center, San Francisco, CA, USABackground: Anterior scleritis is an uncommon form of ocular inflammation, often associated with coexisting autoimmune disease. With early recognition and aggressive systemic therapy, prognosis for resolution is good. The diagnosis of underlying autoimmune disease involves a multidisciplinary approach.Case report: A 42-year-old African American female presented to the Eye Clinic at the San Francisco Veteran Affairs Medical Center, with a tremendously painful left eye, worse on eye movement, with marked injection of conjunctiva. There was mild swelling of the upper eyelid. Visual acuity was unaffected, but there was a mild red cap desaturation. The posterior segment was unremarkable. The initial differential diagnoses included anterior scleritis and orbital inflammatory disease. Oral steroid treatment was initiated with rapid resolution over a few days. Orbital imaging was unremarkable, and extensive laboratory work-up was positive only for antinuclear antibodies. The patient was diagnosed with idiopathic diffuse, nonnecrotizing anterior scleritis and has been followed for over 5 years without recurrence. The rheumatology clinic monitors the patient closely, as suspicion remains for potential arthralgias including human leukocyte antigen-B27-associated arthritis, lupus-associated arthritis, seronegative rheumatoid arthritis, recurrent juvenile idiopathic arthritis, and scleroderma, based on her constitutional symptoms and clinical presentation, along with a positive anti-nuclear antibody lab result.Conclusion: Untreated anterior scleritis can progress to formation of cataracts, glaucoma, uveitis, corneal melting, and posterior segment disease with significant risk of vision loss. Patients with anterior scleritis must be aggressively treated with systemic anti

  19. Human Nonindependent Mate Choice: Is Model Female Attractiveness Everything?

    Directory of Open Access Journals (Sweden)

    Antonios Vakirtzis

    2012-04-01

    Full Text Available Following two decades of research on non-human animals, there has recently been increased interest in human nonindependent mate choice, namely the ways in which choosing women incorporate information about a man's past or present romantic partners (‘model females’ into their own assessment of the male. Experimental studies using static facial images have generally found that men receive higher desirability ratings from female raters when presented with attractive (compared to unattractive model females. This phenomenon has a straightforward evolutionary explanation: the fact that female mate value is more dependent on physical attractiveness compared to male mate value. Furthermore, due to assortative mating for attractiveness, men who are paired with attractive women are more likely to be of high mate value themselves. Here, we also examine the possible relevance of model female cues other than attractiveness (personality and behavioral traits by presenting video recordings of model females to a set of female raters. The results confirm that the model female's attractiveness is the primary cue. Contrary to some earlier findings in the human and nonhuman literature, we found no evidence that female raters prefer partners of slightly older model females. We conclude by suggesting some promising variations on the present experimental design.

  20. Maintenance modeling and optimization integrating human and material resources

    International Nuclear Information System (INIS)

    Martorell, S.; Villamizar, M.; Carlos, S.; Sanchez, A.

    2010-01-01

    Maintenance planning is a subject of concern to many industrial sectors as plant safety and business depend on it. Traditionally, the maintenance planning is formulated in terms of a multi-objective optimization (MOP) problem where reliability, availability, maintainability and cost (RAM+C) act as decision criteria and maintenance strategies (i.e. maintenance tasks intervals) act as the only decision variables. However the appropriate development of each maintenance strategy depends not only on the maintenance intervals but also on the resources (human and material) available to implement such strategies. Thus, the effect of the necessary resources on RAM+C needs to be modeled and accounted for in formulating the MOP affecting the set of objectives and constraints. In this paper RAM+C models to explicitly address the effect of human resources and material resources (spare parts) on RAM+C criteria are proposed. This extended model allows accounting for explicitly how the above decision criteria depends on the basic model parameters representing the type of strategies, maintenance intervals, durations, human resources and material resources. Finally, an application case is performed to optimize the maintenance plan of a motor-driven pump equipment considering as decision variables maintenance and test intervals and human and material resources.

  1. RECONSTRUCTION OF HUMAN LUNG MORPHOLOGY MODELS FROM MAGNETIC RESONANCE IMAGES

    Science.gov (United States)

    Reconstruction of Human Lung Morphology Models from Magnetic Resonance ImagesT. B. Martonen (Experimental Toxicology Division, U.S. EPA, Research Triangle Park, NC 27709) and K. K. Isaacs (School of Public Health, University of North Carolina, Chapel Hill, NC 27514)

  2. 3-D Model of the Human Respiratory System

    Science.gov (United States)

    The U.S. EPA’s Office of Research and Development (ORD) has developed a 3-D computational fluid dynamics (CFD) model of the human respiratory system that allows for the simulation of particulate based contaminant deposition and clearance, while being adaptable for age, ethnicity,...

  3. Maintenance modeling and optimization integrating human and material resources

    Energy Technology Data Exchange (ETDEWEB)

    Martorell, S., E-mail: smartore@iqn.upv.e [Dpto. Ingenieria Quimica y Nuclear, Universidad Politecnica Valencia (Spain); Villamizar, M.; Carlos, S. [Dpto. Ingenieria Quimica y Nuclear, Universidad Politecnica Valencia (Spain); Sanchez, A. [Dpto. Estadistica e Investigacion Operativa Aplicadas y Calidad, Universidad Politecnica Valencia (Spain)

    2010-12-15

    Maintenance planning is a subject of concern to many industrial sectors as plant safety and business depend on it. Traditionally, the maintenance planning is formulated in terms of a multi-objective optimization (MOP) problem where reliability, availability, maintainability and cost (RAM+C) act as decision criteria and maintenance strategies (i.e. maintenance tasks intervals) act as the only decision variables. However the appropriate development of each maintenance strategy depends not only on the maintenance intervals but also on the resources (human and material) available to implement such strategies. Thus, the effect of the necessary resources on RAM+C needs to be modeled and accounted for in formulating the MOP affecting the set of objectives and constraints. In this paper RAM+C models to explicitly address the effect of human resources and material resources (spare parts) on RAM+C criteria are proposed. This extended model allows accounting for explicitly how the above decision criteria depends on the basic model parameters representing the type of strategies, maintenance intervals, durations, human resources and material resources. Finally, an application case is performed to optimize the maintenance plan of a motor-driven pump equipment considering as decision variables maintenance and test intervals and human and material resources.

  4. A murine model of human myeloma bone disease

    NARCIS (Netherlands)

    Garrett, I.R.; Dallas, S.; Radl, J.; Mundy, G.R.

    1997-01-01

    Myeloma causes a devastating and unique form of osteolytic bone disease. Although osteoclast activation is responsible for bone destruction, the precise mechanisms by which myeloma cells increase osteoclast activity have not been defined. An animal model of human myeloma bone disease mould help in

  5. Animal models of human respiratory syncytial virus disease

    NARCIS (Netherlands)

    Bem, Reinout A.; Domachowske, Joseph B.; Rosenberg, Helene F.

    2011-01-01

    Infection with the human pneumovirus pathogen, respiratory syncytial virus (hRSV), causes a wide spectrum of respiratory disease, notably among infants and the elderly. Laboratory animal studies permit detailed experimental modeling of hRSV disease and are therefore indispensable in the search for

  6. Building a 3-D Appearance Model of the Human Face

    DEFF Research Database (Denmark)

    Sjöstrand, Karl; Larsen, Rasmus; Lading, Brian

    2003-01-01

    This paper describes a method for building an appearance model from three-dimensional data of human faces. The data consists of 3-D vertices, polygons and a texture map. The method uses a set of nine manually placed landmarks to automatically form a dense correspondence of thousands of points...

  7. Simplified human thermoregulatory model for designing wearable thermoelectric devices

    Science.gov (United States)

    Wijethunge, Dimuthu; Kim, Donggyu; Kim, Woochul

    2018-02-01

    Research on wearable and implantable devices have become popular with the strong need in market. A precise understanding of the thermal properties of human skin, which are not constant values but vary depending on ambient condition, is required for the development of such devices. In this paper, we present simplified human thermoregulatory model for accurately estimating the thermal properties of the skin without applying rigorous calculations. The proposed model considers a variable blood flow rate through the skin, evaporation functions, and a variable convection heat transfer from the skin surface. In addition, wearable thermoelectric generation (TEG) and refrigeration devices were simulated. We found that deviations of 10-60% can be resulted in estimating TEG performance without considering human thermoregulatory model owing to the fact that thermal resistance of human skin is adapted to ambient condition. Simplicity of the modeling procedure presented in this work could be beneficial for optimizing and predicting the performance of any applications that are directly coupled with skin thermal properties.

  8. Being human: The role of pluripotent stem cells in regenerative medicine and humanizing Alzheimer's disease models.

    Science.gov (United States)

    Sproul, Andrew A

    2015-01-01

    Human pluripotent stem cells (PSCs) have the capacity to revolutionize medicine by allowing the generation of functional cell types such as neurons for cell replacement therapy. However, the more immediate impact of PSCs on treatment of Alzheimer's disease (AD) will be through improved human AD model systems for mechanistic studies and therapeutic screening. This review will first briefly discuss different types of PSCs and genome-editing techniques that can be used to modify PSCs for disease modeling or for personalized medicine. This will be followed by a more in depth analysis of current AD iPSC models and a discussion of the need for more complex multicellular models, including cell types such as microglia. It will finish with a discussion on current clinical trials using PSC-derived cells and the long-term potential of such strategies for treating AD. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Workforce scheduling: A new model incorporating human factors

    Directory of Open Access Journals (Sweden)

    Mohammed Othman

    2012-12-01

    Full Text Available Purpose: The majority of a company’s improvement comes when the right workers with the right skills, behaviors and capacities are deployed appropriately throughout a company. This paper considers a workforce scheduling model including human aspects such as skills, training, workers’ personalities, workers’ breaks and workers’ fatigue and recovery levels. This model helps to minimize the hiring, firing, training and overtime costs, minimize the number of fired workers with high performance, minimize the break time and minimize the average worker’s fatigue level.Design/methodology/approach: To achieve this objective, a multi objective mixed integer programming model is developed to determine the amount of hiring, firing, training and overtime for each worker type.Findings: The results indicate that the worker differences should be considered in workforce scheduling to generate realistic plans with minimum costs. This paper also investigates the effects of human fatigue and recovery on the performance of the production systems.Research limitations/implications: In this research, there are some assumptions that might affect the accuracy of the model such as the assumption of certainty of the demand in each period, and the linearity function of Fatigue accumulation and recovery curves. These assumptions can be relaxed in future work.Originality/value: In this research, a new model for integrating workers’ differences with workforce scheduling is proposed. To the authors' knowledge, it is the first time to study the effects of different important human factors such as human personality, skills and fatigue and recovery in the workforce scheduling process. This research shows that considering both technical and human factors together can reduce the costs in manufacturing systems and ensure the safety of the workers.

  10. A Circuit Model of Real Time Human Body Hydration.

    Science.gov (United States)

    Asogwa, Clement Ogugua; Teshome, Assefa K; Collins, Stephen F; Lai, Daniel T H

    2016-06-01

    Changes in human body hydration leading to excess fluid losses or overload affects the body fluid's ability to provide the necessary support for healthy living. We propose a time-dependent circuit model of real-time human body hydration, which models the human body tissue as a signal transmission medium. The circuit model predicts the attenuation of a propagating electrical signal. Hydration rates are modeled by a time constant τ, which characterizes the individual specific metabolic function of the body part measured. We define a surrogate human body anthropometric parameter θ by the muscle-fat ratio and comparing it with the body mass index (BMI), we find theoretically, the rate of hydration varying from 1.73 dB/min, for high θ and low τ to 0.05 dB/min for low θ and high τ. We compare these theoretical values with empirical measurements and show that real-time changes in human body hydration can be observed by measuring signal attenuation. We took empirical measurements using a vector network analyzer and obtained different hydration rates for various BMI, ranging from 0.6 dB/min for 22.7 [Formula: see text] down to 0.04 dB/min for 41.2 [Formula: see text]. We conclude that the galvanic coupling circuit model can predict changes in the volume of the body fluid, which are essential in diagnosing and monitoring treatment of body fluid disorder. Individuals with high BMI would have higher time-dependent biological characteristic, lower metabolic rate, and lower rate of hydration.

  11. A review on otolith models in human perception.

    Science.gov (United States)

    Asadi, Houshyar; Mohamed, Shady; Lim, Chee Peng; Nahavandi, Saeid

    2016-08-01

    The vestibular system, which consists of semicircular canals and otolith, are the main sensors mammals use to perceive rotational and linear motions. Identifying the most suitable and consistent mathematical model of the vestibular system is important for research related to driving perception. An appropriate vestibular model is essential for implementation of the Motion Cueing Algorithm (MCA) for motion simulation purposes, because the quality of the MCA is directly dependent on the vestibular model used. In this review, the history and development process of otolith models are presented and analyzed. The otolith organs can detect linear acceleration and transmit information about sensed applied specific forces on the human body. The main purpose of this review is to determine the appropriate otolith models that agree with theoretical analyses and experimental results as well as provide reliable estimation for the vestibular system functions. Formulating and selecting the most appropriate mathematical model of the vestibular system is important to ensure successful human perception modelling and simulation when implementing the model into the MCA for motion analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. The organotypic multicellular spheroid is a relevant three-dimensional model to study adenovirus replication and penetration in human tumors in vitro

    NARCIS (Netherlands)

    Grill, Jacques; Lamfers, Martine L. M.; van Beusechem, Victor W.; Dirven, Clemens M.; Pherai, D. Shareen; Kater, Mathijs; van der Valk, Paul; Vogels, Ronald; Vandertop, W. Peter; Pinedo, Herbert M.; Curiel, David T.; Gerritsen, Winald R.

    2002-01-01

    The use of adenoviruses for gene transfer and as oncolytic agents is currently receiving widespread attention. As specific constraints to adenovirus distribution and spread cannot be studied in cell cultures, there is a need for an in vitro three-dimensional (3D) model mimicking the in vivo biology

  13. Genome editing of human pluripotent stem cells to generate human cellular disease models

    Directory of Open Access Journals (Sweden)

    Kiran Musunuru

    2013-07-01

    Full Text Available Disease modeling with human pluripotent stem cells has come into the public spotlight with the awarding of the Nobel Prize in Physiology or Medicine for 2012 to Drs John Gurdon and Shinya Yamanaka for the discovery that mature cells can be reprogrammed to become pluripotent. This discovery has opened the door for the generation of pluripotent stem cells from individuals with disease and the differentiation of these cells into somatic cell types for the study of disease pathophysiology. The emergence of genome-editing technology over the past few years has made it feasible to generate and investigate human cellular disease models with even greater speed and efficiency. Here, recent technological advances in genome editing, and its utility in human biology and disease studies, are reviewed.

  14. A computational model of human auditory signal processing and perception

    DEFF Research Database (Denmark)

    Jepsen, Morten Løve; Ewert, Stephan D.; Dau, Torsten

    2008-01-01

    A model of computational auditory signal-processing and perception that accounts for various aspects of simultaneous and nonsimultaneous masking in human listeners is presented. The model is based on the modulation filterbank model described by Dau et al. [J. Acoust. Soc. Am. 102, 2892 (1997...... discrimination with pure tones and broadband noise, tone-in-noise detection, spectral masking with narrow-band signals and maskers, forward masking with tone signals and tone or noise maskers, and amplitude-modulation detection with narrow- and wideband noise carriers. The model can account for most of the key...... properties of the data and is more powerful than the original model. The model might be useful as a front end in technical applications....

  15. Computational model of soft tissues in the human upper airway.

    Science.gov (United States)

    Pelteret, J-P V; Reddy, B D

    2012-01-01

    This paper presents a three-dimensional finite element model of the tongue and surrounding soft tissues with potential application to the study of sleep apnoea and of linguistics and speech therapy. The anatomical data was obtained from the Visible Human Project, and the underlying histological data was also extracted and incorporated into the model. Hyperelastic constitutive models were used to describe the material behaviour, and material incompressibility was accounted for. An active Hill three-element muscle model was used to represent the muscular tissue of the tongue. The neural stimulus for each muscle group was determined through the use of a genetic algorithm-based neural control model. The fundamental behaviour of the tongue under gravitational and breathing-induced loading is investigated. It is demonstrated that, when a time-dependent loading is applied to the tongue, the neural model is able to control the position of the tongue and produce a physiologically realistic response for the genioglossus.

  16. Growth Modeling of Human Mandibles using Non-Euclidean Metrics

    DEFF Research Database (Denmark)

    Hilger, Klaus Baggesen; Larsen, Rasmus; Wrobel, Mark

    2003-01-01

    From a set of 31 three-dimensional CT scans we model the temporal shape and size of the human mandible. Each anatomical structure is represented using 14851 semi-landmarks, and mapped into Procrustes tangent space. Exploratory subspace analyses are performed leading to linear models of mandible...... shape evolution in Procrustes space. The traditional variance analysis results in a one-dimensional growth model. However, working in a non-Euclidean metric results in a multimodal model with uncorrelated modes of biological variation. The applied non-Euclidean metric is governed by the correlation...... structure of the estimated noise in the data. The generative models are compared, and evaluated on the basis of a cross validation study. The new non-Euclidean analysis is completely data driven. It not only gives comparable results w.r.t. to previous studies of the mean modelling error, but in addition...

  17. Analyzing, Modeling, and Simulation for Human Dynamics in Social Network

    Directory of Open Access Journals (Sweden)

    Yunpeng Xiao

    2012-01-01

    Full Text Available This paper studies the human behavior in the top-one social network system in China (Sina Microblog system. By analyzing real-life data at a large scale, we find that the message releasing interval (intermessage time obeys power law distribution both at individual level and at group level. Statistical analysis also reveals that human behavior in social network is mainly driven by four basic elements: social pressure, social identity, social participation, and social relation between individuals. Empirical results present the four elements' impact on the human behavior and the relation between these elements. To further understand the mechanism of such dynamic phenomena, a hybrid human dynamic model which combines “interest” of individual and “interaction” among people is introduced, incorporating the four elements simultaneously. To provide a solid evaluation, we simulate both two-agent and multiagent interactions with real-life social network topology. We achieve the consistent results between empirical studies and the simulations. The model can provide a good understanding of human dynamics in social network.

  18. A transparent model of the human scala tympani cavity.

    Science.gov (United States)

    Rebscher, S J; Talbot, N; Bruszewski, W; Heilmann, M; Brasell, J; Merzenich, M M

    1996-01-01

    A dimensionally accurate clear model of the human scala tympani has been produced to evaluate the insertion and position of clinically applied intracochlear electrodes for electrical stimulation. Replicates of the human scala tympani were made from low melting point metal alloy (LMA) and from polymethylmeth-acrylate (PMMA) resin. The LMA metal casts were embedded in blocks of epoxy and in clear silicone rubber. After removal of the metal alloy, a cavity was produced that accurately models the human scala tympani. Investment casting molds were made from the PMMA scala tympani casts to enable production of multiple LMA casts from which identical models were fabricated. Total dimensional distortion of the LMA casting process was less than 1% in length and 2% in diameter. The models have been successfully integrated into the design process for the iterative development of advanced intracochlear electrode arrays at UCSF. These fabrication techniques are applicable to a wide range of biomedical design problems that require modelling of visually obscured cavities.

  19. Learning from video modeling examples : Effects of seeing the human model's face

    NARCIS (Netherlands)

    Van Gog, Tamara; Verveer, Ilse; Verveer, Lise

    2014-01-01

    Video modeling examples in which a human(-like) model shows learners how to perform a task are increasingly used in education, as they have become very easy to create and distribute in e-learning environments. However, little is known about design guidelines to optimize learning from video modeling

  20. Bioprinted three dimensional human tissues for toxicology and disease modeling.

    Science.gov (United States)

    Nguyen, Deborah G; Pentoney, Stephen L

    2017-03-01

    The high rate of attrition among clinical-stage therapies, due largely to an inability to predict human toxicity and/or efficacy, underscores the need for in vitro models that better recapitulate in vivo human biology. In much the same way that additive manufacturing has revolutionized the production of solid objects, three-dimensional (3D) bioprinting is enabling the automated production of more architecturally and functionally accurate in vitro tissue culture models. Here, we provide an overview of the most commonly used bioprinting approaches and how they are being used to generate complex in vitro tissues for use in toxicology and disease modeling research. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Modelling human resource requirements for the nuclear industry in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Roelofs, Ferry [Nuclear Research and Consultancy Group (NRG) (Netherlands); Flore, Massimo; Estorff, Ulrik von [Joint Research Center (JRC) (Netherlands)

    2017-11-15

    The European Human Resource Observatory for Nuclear (EHRO-N) provides the European Commission with essential data related to supply and demand for nuclear experts in the EU-28 and the enlargement and integration countries based on bottom-up information from the nuclear industry. The objective is to assess how the supply of experts for the nuclear industry responds to the needs for the same experts for present and future nuclear projects in the region. Complementary to the bottom-up approach taken by the EHRO-N team at JRC, a top-down modelling approach has been taken in a collaboration with NRG in the Netherlands. This top-down modelling approach focuses on the human resource requirements for operation, construction, decommissioning, and efforts for long term operation of nuclear power plants. This paper describes the top-down methodology, the model input, the main assumptions, and the results of the analyses.

  2. A Culture-Behavior-Brain Loop Model of Human Development.

    Science.gov (United States)

    Han, Shihui; Ma, Yina

    2015-11-01

    Increasing evidence suggests that cultural influences on brain activity are associated with multiple cognitive and affective processes. These findings prompt an integrative framework to account for dynamic interactions between culture, behavior, and the brain. We put forward a culture-behavior-brain (CBB) loop model of human development that proposes that culture shapes the brain by contextualizing behavior, and the brain fits and modifies culture via behavioral influences. Genes provide a fundamental basis for, and interact with, the CBB loop at both individual and population levels. The CBB loop model advances our understanding of the dynamic relationships between culture, behavior, and the brain, which are crucial for human phylogeny and ontogeny. Future brain changes due to cultural influences are discussed based on the CBB loop model. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Pearls and pitfalls in human pharmacological models of migraine

    DEFF Research Database (Denmark)

    Ashina, Messoud; Hansen, Jakob Møller; Olesen, Jes

    2013-01-01

    In vitro studies have contributed to the characterization of receptors in cranial blood vessels and the identification of new possible anti-migraine agents. In vivo animal models enable the study of vascular responses, neurogenic inflammation, peptide release and genetic predisposition and thus......- or migraine-provoking property of naturally occurring signaling molecules can be tested in a human model. If such an endogenous substance can provoke migraine in human patients, then it is likely, although not certain, that blocking its effect will be effective in the treatment of acute migraine attacks...... an important role in translational migraine research leading to the identification of three new principally different targets in the treatment of acute migraine attacks and has been used to examine other endogenous signaling molecules as well as genetic susceptibility factors. New additions to the model...

  4. New paradigms for metabolic modeling of human cells

    DEFF Research Database (Denmark)

    Mardinoglu, Adil; Nielsen, Jens

    2015-01-01

    review recent work on reconstruction of GEMs for human cell/tissue types and cancer, and the use of GEMs for identification of metabolic changes occurring in response to disease development. We further discuss how GEMs can be used for the development of efficient therapeutic strategies. Finally......, challenges in integration of cell/tissue models for simulation of whole body functions as well as integration of GEMs with other biological networks for generating complete cell/tissue models are presented.......Abnormalities in cellular functions are associated with the progression of human diseases, often resulting in metabolic reprogramming. GEnome-scale metabolic Models (GEMs) have enabled studying global metabolic reprogramming in connection with disease development in a systematic manner. Here we...

  5. Modelling human resource requirements for the nuclear industry in Europe

    International Nuclear Information System (INIS)

    Roelofs, Ferry; Flore, Massimo; Estorff, Ulrik von

    2017-01-01

    The European Human Resource Observatory for Nuclear (EHRO-N) provides the European Commission with essential data related to supply and demand for nuclear experts in the EU-28 and the enlargement and integration countries based on bottom-up information from the nuclear industry. The objective is to assess how the supply of experts for the nuclear industry responds to the needs for the same experts for present and future nuclear projects in the region. Complementary to the bottom-up approach taken by the EHRO-N team at JRC, a top-down modelling approach has been taken in a collaboration with NRG in the Netherlands. This top-down modelling approach focuses on the human resource requirements for operation, construction, decommissioning, and efforts for long term operation of nuclear power plants. This paper describes the top-down methodology, the model input, the main assumptions, and the results of the analyses.

  6. An Integrated Simulation Tool for Modeling the Human Circulatory System

    Science.gov (United States)

    Asami, Ken'ichi; Kitamura, Tadashi

    This paper presents an integrated simulation of the circulatory system in physiological movement. The large circulatory system model includes principal organs and functional units in modules in which comprehensive physiological changes such as nerve reflexes, temperature regulation, acid/base balance, O2/CO2 balance, and exercise are simulated. A beat-by-beat heart model, in which the corresponding electrical circuit problems are solved by a numerical analytic method, enables calculation of pulsatile blood flow to the major organs. The integration of different perspectives on physiological changes makes this simulation model applicable for the microscopic evaluation of blood flow under various conditions in the human body.

  7. Multibody model of the human upper extremity for fracture simulation

    OpenAIRE

    Milanowicz, Marcin; K?dzior, Krzysztof

    2016-01-01

    About 3.8 million people are injured in accidents at work in Europe every year. The resulting high costs are incurred by the victims themselves, their families, employers and society. We have used a numerical simulation to reconstruct accidents at work for several years. To reconstruct these accidents MADYMO R7.5 with a numerical human model (pedestrian model) is used. However, this model is dedicated to the analysis of car-to-pedestrian accidents and thus cannot be fully used for reconstruct...

  8. Hirarchical emotion calculation model for virtual human modellin - biomed 2010.

    Science.gov (United States)

    Zhao, Yue; Wright, David

    2010-01-01

    This paper introduces a new emotion generation method for virtual human modelling. The method includes a novel hierarchical emotion structure, a group of emotion calculation equations and a simple heuristics decision making mechanism, which enables virtual humans to perform emotionally in real-time according to their internal and external factors. Emotion calculation equations used in this research were derived from psychologic emotion measurements. Virtual humans can utilise the information in virtual memory and emotion calculation equations to generate their own numerical emotion states within the hierarchical emotion structure. Those emotion states are important internal references for virtual humans to adopt appropriate behaviours and also key cues for their decision making. A simple heuristics theory is introduced and integrated into decision making process in order to make the virtual humans decision making more like a real human. A data interface which connects the emotion calculation and the decision making structure together has also been designed and simulated to test the method in Virtools environment.

  9. Modeling and Visualization of Human Activities for Multicamera Networks

    Directory of Open Access Journals (Sweden)

    Aswin C. Sankaranarayanan

    2009-01-01

    Full Text Available Multicamera networks are becoming complex involving larger sensing areas in order to capture activities and behavior that evolve over long spatial and temporal windows. This necessitates novel methods to process the information sensed by the network and visualize it for an end user. In this paper, we describe a system for modeling and on-demand visualization of activities of groups of humans. Using the prior knowledge of the 3D structure of the scene as well as camera calibration, the system localizes humans as they navigate the scene. Activities of interest are detected by matching models of these activities learnt a priori against the multiview observations. The trajectories and the activity index for each individual summarize the dynamic content of the scene. These are used to render the scene with virtual 3D human models that mimic the observed activities of real humans. In particular, the rendering framework is designed to handle large displays with a cluster of GPUs as well as reduce the cognitive dissonance by rendering realistic weather effects and illumination. We envision use of this system for immersive visualization as well as summarization of videos that capture group behavior.

  10. Multivariate Models for Prediction of Human Skin Sensitization ...

    Science.gov (United States)

    One of the lnteragency Coordinating Committee on the Validation of Alternative Method's (ICCVAM) top priorities is the development and evaluation of non-animal approaches to identify potential skin sensitizers. The complexity of biological events necessary to produce skin sensitization suggests that no single alternative method will replace the currently accepted animal tests. ICCVAM is evaluating an integrated approach to testing and assessment based on the adverse outcome pathway for skin sensitization that uses machine learning approaches to predict human skin sensitization hazard. We combined data from three in chemico or in vitro assays - the direct peptide reactivity assay (DPRA), human cell line activation test (h-CLAT) and KeratinoSens TM assay - six physicochemical properties and an in silico read-across prediction of skin sensitization hazard into 12 variable groups. The variable groups were evaluated using two machine learning approaches , logistic regression and support vector machine, to predict human skin sensitization hazard. Models were trained on 72 substances and tested on an external set of 24 substances. The six models (three logistic regression and three support vector machine) with the highest accuracy (92%) used: (1) DPRA, h-CLAT and read-across; (2) DPRA, h-CLAT, read-across and KeratinoSens; or (3) DPRA, h-CLAT, read-across, KeratinoSens and log P. The models performed better at predicting human skin sensitization hazard than the murine

  11. Culture models of human mammary epithelial cell transformation

    Energy Technology Data Exchange (ETDEWEB)

    Stampfer, Martha R.; Yaswen, Paul

    2000-11-10

    Human pre-malignant breast diseases, particularly ductal carcinoma in situ (DCIS)3 already display several of the aberrant phenotypes found in primary breast cancers, including chromosomal abnormalities, telomerase activity, inactivation of the p53 gene and overexpression of some oncogenes. Efforts to model early breast carcinogenesis in human cell cultures have largely involved studies in vitro transformation of normal finite lifespan human mammary epithelial cells (HMEC) to immortality and malignancy. We present a model of HMEC immortal transformation consistent with the know in vivo data. This model includes a recently described, presumably epigenetic process, termed conversion, which occurs in cells that have overcome stringent replicative senescence and are thus able to maintain proliferation with critically short telomeres. The conversion process involves reactivation of telomerase activity, and acquisition of good uniform growth in the absence and presence of TFGB. We propose th at overcoming the proliferative constraints set by senescence, and undergoing conversion, represent key rate-limiting steps in human breast carcinogenesis, and occur during early stage breast cancer progression.

  12. Modelling the basic error tendencies of human operators

    Energy Technology Data Exchange (ETDEWEB)

    Reason, J.

    1988-01-01

    The paper outlines the primary structural features of human cognition: a limited, serial workspace interacting with a parallel distributed knowledge base. It is argued that the essential computational features of human cognition - to be captured by an adequate operator model - reside in the mechanisms by which stored knowledge structures are selected and brought into play. Two such computational 'primitives' are identified: similarity-matching and frequency-gambling. These two retrieval heuristics, it is argued, shape both the overall character of human performance (i.e. its heavy reliance on pattern-matching) and its basic error tendencies ('strong-but-wrong' responses, confirmation, similarity and frequency biases, and cognitive 'lock-up'). The various features of human cognition are integrated with a dynamic operator model capable of being represented in software form. This computer model, when run repeatedly with a variety of problem configurations, should produce a distribution of behaviours which, in toto, simulate the general character of operator performance.

  13. Personalized medicine for cystic fibrosis: establishing human model systems.

    Science.gov (United States)

    Mou, Hongmei; Brazauskas, Karissa; Rajagopal, Jayaraj

    2015-10-01

    With over 1,500 identifiable mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene that result in distinct functional and phenotypical abnormalities, it is virtually impossible to perform randomized clinical trials to identify the best therapeutics for all patients. Therefore, a personalized medicine approach is essential. The only way to realistically accomplish this is through the development of improved in vitro human model systems. The lack of a readily available and infinite supply of human CFTR-expressing airway epithelial cells is a key bottleneck. We propose that a concerted two-pronged approach is necessary for patient-specific cystic fibrosis research to continue to prosper and realize its potential: (1) more effective culture and differentiation conditions for growing primary human airway and nasal epithelial cells and (2) the development of collective protocols for efficiently differentiating disease- and patient-specific induced pluripotent stem cells (iPSC) into pure populations of adult epithelial cells. Ultimately, we need a personalized human model system for cystic fibrosis with the capacity for uncomplicated bankability, widespread availability, and universal applicability for patient-specific disease modeling, novel pharmacotherapy investigation and screening, and readily executable genetic modification. © 2015 Wiley Periodicals, Inc.

  14. 1-D blood flow modelling in a running human body.

    Science.gov (United States)

    Szabó, Viktor; Halász, Gábor

    2017-07-01

    In this paper an attempt was made to simulate blood flow in a mobile human arterial network, specifically, in a running human subject. In order to simulate the effect of motion, a previously published immobile 1-D model was modified by including an inertial force term into the momentum equation. To calculate inertial force, gait analysis was performed at different levels of speed. Our results show that motion has a significant effect on the amplitudes of the blood pressure and flow rate but the average values are not effected significantly.

  15. Modeling human diseases: an education in interactions and interdisciplinary approaches

    Directory of Open Access Journals (Sweden)

    Leonard Zon

    2016-06-01

    Full Text Available Traditionally, most investigators in the biomedical arena exploit one model system in the course of their careers. Occasionally, an investigator will switch models. The selection of a suitable model system is a crucial step in research design. Factors to consider include the accuracy of the model as a reflection of the human disease under investigation, the numbers of animals needed and ease of husbandry, its physiology and developmental biology, and the ability to apply genetics and harness the model for drug discovery. In my lab, we have primarily used the zebrafish but combined it with other animal models and provided a framework for others to consider the application of developmental biology for therapeutic discovery. Our interdisciplinary approach has led to many insights into human diseases and to the advancement of candidate drugs to clinical trials. Here, I draw on my experiences to highlight the importance of combining multiple models, establishing infrastructure and genetic tools, forming collaborations, and interfacing with the medical community for successful translation of basic findings to the clinic.

  16. Cognition and procedure representational requirements for predictive human performance models

    Science.gov (United States)

    Corker, K.

    1992-01-01

    Models and modeling environments for human performance are becoming significant contributors to early system design and analysis procedures. Issues of levels of automation, physical environment, informational environment, and manning requirements are being addressed by such man/machine analysis systems. The research reported here investigates the close interaction between models of human cognition and models that described procedural performance. We describe a methodology for the decomposition of aircrew procedures that supports interaction with models of cognition on the basis of procedures observed; that serves to identify cockpit/avionics information sources and crew information requirements; and that provides the structure to support methods for function allocation among crew and aiding systems. Our approach is to develop an object-oriented, modular, executable software representation of the aircrew, the aircraft, and the procedures necessary to satisfy flight-phase goals. We then encode in a time-based language, taxonomies of the conceptual, relational, and procedural constraints among the cockpit avionics and control system and the aircrew. We have designed and implemented a goals/procedures hierarchic representation sufficient to describe procedural flow in the cockpit. We then execute the procedural representation in simulation software and calculate the values of the flight instruments, aircraft state variables and crew resources using the constraints available from the relationship taxonomies. The system provides a flexible, extensible, manipulative and executable representation of aircrew and procedures that is generally applicable to crew/procedure task-analysis. The representation supports developed methods of intent inference, and is extensible to include issues of information requirements and functional allocation. We are attempting to link the procedural representation to models of cognitive functions to establish several intent inference methods

  17. Models of Human Information Requirements: "When Reasonable Aiding Systems Disagree"

    Science.gov (United States)

    Corker, Kevin; Pisanich, Gregory; Shafto, Michael (Technical Monitor)

    1994-01-01

    Aircraft flight management and Air Traffic Control (ATC) automation are under development to maximize the economy of flight and to increase the capacity of the terminal area airspace while maintaining levels of flight safety equal to or better than current system performance. These goals are being realized by the introduction of flight management automation aiding and operations support systems on the flight deck and by new developments of ATC aiding systems that seek to optimize scheduling of aircraft while potentially reducing required separation and accounting for weather and wake vortex turbulence. Aiding systems on both the flight deck and the ground operate through algorithmic functions on models of the aircraft and of the airspace. These models may differ from each other as a result of variations in their models of the immediate environment. The resultant flight operations or ATC commands may differ in their response requirements (e.g. different preferred descent speeds or descent initiation points). The human operators in the system must then interact with the automation to reconcile differences and resolve conflicts. We have developed a model of human performance including cognitive functions (decision-making, rule-based reasoning, procedural interruption recovery and forgetting) that supports analysis of the information requirements for resolution of flight aiding and ATC conflicts. The model represents multiple individuals in the flight crew and in ATC. The model is supported in simulation on a Silicon Graphics' workstation using Allegro Lisp. Design guidelines for aviation automation aiding systems have been developed using the model's specification of information and team procedural requirements. Empirical data on flight deck operations from full-mission flight simulation are provided to support the model's predictions. The paper describes the model, its development and implementation, the simulation test of the model predictions, and the empirical

  18. A Language for Modeling Cultural Norms, Biases and Stereotypes for Human Behavior Models

    National Research Council Canada - National Science Library

    Solomon, Steven; van Lent, Michael; Core, Mark; Carpenter, Paul; Rosenberg, Milton

    2008-01-01

    .... The Culturally-Affected Behavior project seeks to define a language for encoding ethnographic data in order to capture cultural knowledge and use that knowledge to affect human behavior models...

  19. Nerve cell-mimicking liposomes as biosensor for botulinum neurotoxin complete physiological activity

    Energy Technology Data Exchange (ETDEWEB)

    Weingart, Oliver G., E-mail: Oliver.Weingart@hest.ethz.ch; Loessner, Martin J.

    2016-12-15

    Botulinum neurotoxins (BoNT) are the most toxic substances known, and their neurotoxic properties and paralysing effects are exploited for medical treatment of a wide spectrum of disorders. To accurately quantify the potency of a pharmaceutical BoNT preparation, its physiological key activities (binding to membrane receptor, translocation, and proteolytic degradation of SNARE proteins) need to be determined. To date, this was only possible using animal models, or, to a limited extent, cell-based assays. We here report a novel in vitro system for BoNT/B analysis, based on nerve-cell mimicking liposomes presenting motoneuronal membrane receptors required for BoNT binding. Following triggered membrane translocation of the toxin's Light Chain, the endopeptidase activity can be quantitatively monitored employing a FRET-based reporter assay within the functionalized liposomes. We were able to detect BoNT/B physiological activity at picomolar concentrations in short time, opening the possibility for future replacement of animal experimentation in pharmaceutical BoNT testing. - Highlights: • A cell-free in vitro system was used to measure BoNT/B physiological function. • The system relies on nerve-cell mimicking liposomes as a novel detection system. • A FRET-based reporter assay is used as final readout of the test system. • BoNT/B physiological activity was detected at picogram quantities in short time. • The method opens the possibility to replace animal experimentation in BoNT testing.

  20. Transport of silver nanoparticles from nanocomposite Ag/alginate hydrogels under conditions mimicking tissue implantation

    Directory of Open Access Journals (Sweden)

    Kostić Danijela D.

    2017-01-01

    Full Text Available The aim of this work was to assess phenomena occurring during AgNP transport from nanocomposite Ag/alginate hydrogels under conditions relevant for potential biomedical applications as antimicrobial soft tissue implants. First, we have studied AgNP migration from the nanocomposite to the adjacent alginate hydrogel mimicking soft tissue next to the implant. AgNP deposition was carried out by the initial burst release lasting for ∼24 h yielding large aggregates on hydrogel surfaces and smaller clusters (∼400 nm in size inside. However, the overall released content was low (0.67% indicating high nanocomposite stability. In the next experimental series, release of AgNPs, 10–30 nm in size, from Ag/alginate microbeads in water was investigated under static conditions as well as under continuous perfusion mimicking vascularized tissues. Mathematical modeling has revealed AgNP release by diffusion under static conditions with the diffusion coefficient within the Ag/alginate hydrogel of 6.9x10–19 m2 s–1. Conversely, continuous perfusion induced increased AgNP release by convection with the interstitial fluid velocity estimated as 4.6 nm s–1. Overall, the obtained results indicated the influence of hydrodynamic conditions at the implantation site on silver release and potential implant functionality, which should be investigated at the experimentation beginning using appropriate in vitro systems. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 45019

  1. Nanosecond laser pulses for mimicking thermal effects on nanostructured tungsten-based materials

    Science.gov (United States)

    Besozzi, E.; Maffini, A.; Dellasega, D.; Russo, V.; Facibeni, A.; Pazzaglia, A.; Beghi, M. G.; Passoni, M.

    2018-03-01

    In this work, we exploit nanosecond laser irradiation as a compact solution for investigating the thermomechanical behavior of tungsten materials under extreme thermal loads at the laboratory scale. Heat flux factor thresholds for various thermal effects, such as melting, cracking and recrystallization, are determined under both single and multishot experiments. The use of nanosecond lasers for mimicking thermal effects induced on W by fusion-relevant thermal loads is thus validated by direct comparison of the thresholds obtained in this work and the ones reported in the literature for electron beams and millisecond laser irradiation. Numerical simulations of temperature and thermal stress performed on a 2D thermomechanical code are used to predict the heat flux factor thresholds of the different thermal effects. We also investigate the thermal effect thresholds of various nanostructured W coatings. These coatings are produced by pulsed laser deposition, mimicking W coatings in tokamaks and W redeposited layers. All the coatings show lower damage thresholds with respect to bulk W. In general, thresholds decrease as the porosity degree of the materials increases. We thus propose a model to predict these thresholds for coatings with various morphologies, simply based on their porosity degree, which can be directly estimated by measuring the variation of the coating mass density with respect to that of the bulk.

  2. Nerve cell-mimicking liposomes as biosensor for botulinum neurotoxin complete physiological activity

    International Nuclear Information System (INIS)

    Weingart, Oliver G.; Loessner, Martin J.

    2016-01-01

    Botulinum neurotoxins (BoNT) are the most toxic substances known, and their neurotoxic properties and paralysing effects are exploited for medical treatment of a wide spectrum of disorders. To accurately quantify the potency of a pharmaceutical BoNT preparation, its physiological key activities (binding to membrane receptor, translocation, and proteolytic degradation of SNARE proteins) need to be determined. To date, this was only possible using animal models, or, to a limited extent, cell-based assays. We here report a novel in vitro system for BoNT/B analysis, based on nerve-cell mimicking liposomes presenting motoneuronal membrane receptors required for BoNT binding. Following triggered membrane translocation of the toxin's Light Chain, the endopeptidase activity can be quantitatively monitored employing a FRET-based reporter assay within the functionalized liposomes. We were able to detect BoNT/B physiological activity at picomolar concentrations in short time, opening the possibility for future replacement of animal experimentation in pharmaceutical BoNT testing. - Highlights: • A cell-free in vitro system was used to measure BoNT/B physiological function. • The system relies on nerve-cell mimicking liposomes as a novel detection system. • A FRET-based reporter assay is used as final readout of the test system. • BoNT/B physiological activity was detected at picogram quantities in short time. • The method opens the possibility to replace animal experimentation in BoNT testing.

  3. Mimicking exposures to acute and lifetime concentrations of inhaled silver nanoparticles by two different in vitro approaches

    Directory of Open Access Journals (Sweden)

    Fabian Herzog

    2014-08-01

    Full Text Available In the emerging market of nano-sized products, silver nanoparticles (Ag NPs are widely used due to their antimicrobial properties. Human interaction with Ag NPs can occur through the lung, skin, gastrointestinal tract, and bloodstream. However, the inhalation of Ag NP aerosols is a primary concern. To study the possible effects of inhaled Ag NPs, an in vitro triple cell co-culture model of the human alveolar/airway barrier (A549 epithelial cells, human peripheral blood monocyte derived dendritic and macrophage cells together with an air–liquid interface cell exposure (ALICE system was used in order to reflect a real-life exposure scenario. Cells were exposed at the air–liquid interface (ALI to 0.03, 0.3, and 3 µg Ag/cm2 of Ag NPs (diameter 100 nm; coated with polyvinylpyrrolidone: PVP. Ag NPs were found to be highly aggregated within ALI exposed cells with no impairment of cell morphology. Furthermore, a significant increase in release of cytotoxic (LDH, oxidative stress (SOD-1, HMOX-1 or pro-inflammatory markers (TNF-α, IL-8 was absent. As a comparison, cells were exposed to Ag NPs in submerged conditions to 10, 20, and 30 µg Ag/mL. The deposited dose per surface area was estimated by using a dosimetry model (ISDD to directly compare submerged vs ALI exposure concentrations after 4 and 24 h. Unlike ALI exposures, the two highest concentrations under submerged conditions promoted a cytotoxic and pro-inflammatory response after 24 h. Interestingly, when cell cultures were co-incubated with lipopolysaccharide (LPS, no synergistic inflammatory effects were observed. By using two different exposure scenarios it has been shown that the ALI as well as the suspension conditions for the lower concentrations after 4 h, reflecting real-life concentrations of an acute 24 h exposure, did not induce any adverse effects in a complex 3D model mimicking the human alveolar/airway barrier. However, the highest concentrations used in the ALI setup, as well

  4. Multi-model approach to characterize human handwriting motion.

    Science.gov (United States)

    Chihi, I; Abdelkrim, A; Benrejeb, M

    2016-02-01

    This paper deals with characterization and modelling of human handwriting motion from two forearm muscle activity signals, called electromyography signals (EMG). In this work, an experimental approach was used to record the coordinates of a pen tip moving on the (x, y) plane and EMG signals during the handwriting act. The main purpose is to design a new mathematical model which characterizes this biological process. Based on a multi-model approach, this system was originally developed to generate letters and geometric forms written by different writers. A Recursive Least Squares algorithm is used to estimate the parameters of each sub-model of the multi-model basis. Simulations show good agreement between predicted results and the recorded data.

  5. Modelling large scale human activity in San Francisco

    Science.gov (United States)

    Gonzalez, Marta

    2010-03-01

    Diverse group of people with a wide variety of schedules, activities and travel needs compose our cities nowadays. This represents a big challenge for modeling travel behaviors in urban environments; those models are of crucial interest for a wide variety of applications such as traffic forecasting, spreading of viruses, or measuring human exposure to air pollutants. The traditional means to obtain knowledge about travel behavior is limited to surveys on travel journeys. The obtained information is based in questionnaires that are usually costly to implement and with intrinsic limitations to cover large number of individuals and some problems of reliability. Using mobile phone data, we explore the basic characteristics of a model of human travel: The distribution of agents is proportional to the population density of a given region, and each agent has a characteristic trajectory size contain information on frequency of visits to different locations. Additionally we use a complementary data set given by smart subway fare cards offering us information about the exact time of each passenger getting in or getting out of the subway station and the coordinates of it. This allows us to uncover the temporal aspects of the mobility. Since we have the actual time and place of individual's origin and destination we can understand the temporal patterns in each visited location with further details. Integrating two described data set we provide a dynamical model of human travels that incorporates different aspects observed empirically.

  6. A human cadaver fascial compartment pressure measurement model.

    Science.gov (United States)

    Messina, Frank C; Cooper, Dylan; Huffman, Gretchen; Bartkus, Edward; Wilbur, Lee

    2013-10-01

    Fresh human cadavers provide an effective model for procedural training. Currently, there are no realistic models to teach fascial compartment pressure measurement. We created a human cadaver fascial compartment pressure measurement model and studied its feasibility with a pre-post design. Three faculty members, following instructions from a common procedure textbook, used a standard handheld intra-compartment pressure monitor (Stryker(®), Kalamazoo, MI) to measure baseline pressures ("unembalmed") in the anterior, lateral, deep posterior, and superficial posterior compartments of the lower legs of a fresh human cadaver. The right femoral artery was then identified by superficial dissection, cannulated distally towards the lower leg, and connected to a standard embalming machine. After a 5-min infusion, the same three faculty members re-measured pressures ("embalmed") of the same compartments on the cannulated right leg. Unembalmed and embalmed readings for each compartment, and baseline readings for each leg, were compared using a two-sided paired t-test. The mean baseline compartment pressures did not differ between the right and left legs. Using the embalming machine, compartment pressure readings increased significantly over baseline for three of four fascial compartments; all in mm Hg (±SD): anterior from 40 (±9) to 143 (±44) (p = 0.08); lateral from 22 (±2.5) to 160 (±4.3) (p cadaver using a standard embalming machine. Set-up is minimal and the model can be incorporated into teaching curricula. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. The Non-Human Primate Experimental Glaucoma Model

    Science.gov (United States)

    Burgoyne, Claude F.

    2015-01-01

    The purpose of this report is to summarize the current strengths and weaknesses of the non-human primate (NHP) experimental glaucoma (EG) model through sections devoted to its history, methods, important findings, alternative optic neuropathy models and future directions. NHP EG has become well established for studying human glaucoma in part because the NHP optic nerve head (ONH) shares a close anatomic association with the human ONH and because it provides the only means of systematically studying the very earliest visual system responses to chronic IOP elevation, i.e. the conversion from ocular hypertension to glaucomatous damage. However, NHPs are impractical for studies that require large animal numbers, demonstrate spontaneous glaucoma only rarely, do not currently provide a model of the neuropathy at normal levels of IOP, and cannot easily be genetically manipulated, except through tissue-specific, viral vectors. The goal of this summary is to direct NHP EG and non-NHP EG investigators to the previous, current and future accomplishment of clinically relevant knowledge in this model. PMID:26070984

  8. Hologram QSAR model for the prediction of human oral bioavailability.

    Science.gov (United States)

    Moda, Tiago L; Montanari, Carlos A; Andricopulo, Adriano D

    2007-12-15

    A drug intended for use in humans should have an ideal balance of pharmacokinetics and safety, as well as potency and selectivity. Unfavorable pharmacokinetics can negatively affect the clinical development of many otherwise promising drug candidates. A variety of in silico ADME (absorption, distribution, metabolism, and excretion) models are receiving increased attention due to a better appreciation that pharmacokinetic properties should be considered in early phases of the drug discovery process. Human oral bioavailability is an important pharmacokinetic property, which is directly related to the amount of drug available in the systemic circulation to exert pharmacological and therapeutic effects. In the present work, hologram quantitative structure-activity relationships (HQSAR) were performed on a training set of 250 structurally diverse molecules with known human oral bioavailability. The most significant HQSAR model (q(2)=0.70, r(2)=0.93) was obtained using atoms, bond, connection, and chirality as fragment distinction. The predictive ability of the model was evaluated by an external test set containing 52 molecules not included in the training set, and the predicted values were in good agreement with the experimental values. The HQSAR model should be useful for the design of new drug candidates having increased bioavailability as well as in the process of chemical library design, virtual screening, and high-throughput screening.

  9. Are animal models predictive for human postmortem muscle protein degradation?

    Science.gov (United States)

    Ehrenfellner, Bianca; Zissler, Angela; Steinbacher, Peter; Monticelli, Fabio C; Pittner, Stefan

    2017-11-01

    A most precise determination of the postmortem interval (PMI) is a crucial aspect in forensic casework. Although there are diverse approaches available to date, the high heterogeneity of cases together with the respective postmortal changes often limit the validity and sufficiency of many methods. Recently, a novel approach for time since death estimation by the analysis of postmortal changes of muscle proteins was proposed. It is however necessary to improve the reliability and accuracy, especially by analysis of possible influencing factors on protein degradation. This is ideally investigated on standardized animal models that, however, require legitimization by a comparison of human and animal tissue, and in this specific case of protein degradation profiles. Only if protein degradation events occur in comparable fashion within different species, respective findings can sufficiently be transferred from the animal model to application in humans. Therefor samples from two frequently used animal models (mouse and pig), as well as forensic cases with representative protein profiles of highly differing PMIs were analyzed. Despite physical and physiological differences between species, western blot analysis revealed similar patterns in most of the investigated proteins. Even most degradation events occurred in comparable fashion. In some other aspects, however, human and animal profiles depicted distinct differences. The results of this experimental series clearly indicate the huge importance of comparative studies, whenever animal models are considered. Although animal models could be shown to reflect the basic principles of protein degradation processes in humans, we also gained insight in the difficulties and limitations of the applicability of the developed methodology in different mammalian species regarding protein specificity and methodic functionality.

  10. A theoretical and experimental investigation of nonlinear propagation of ultrasound through tissue mimicking media

    Science.gov (United States)

    Rielly, Matthew Robert

    An existing numerical model (known as the Bergen code) is used to investigate finite amplitude ultrasound propagation through multiple layers of tissue-like media. This model uses a finite difference method to solve the nonlinear parabolic KZK wave equation. The code is modified to include an arbitrary frequency dependence of absorption and transmission effects for wave propagation across a plane interface at normal incidence. In addition the code is adapted to calculate the total intensity loss associated with the absorption of the fundamental and nonlinearly generated harmonics. Measurements are also taken of the axial nonlinear pressure field generated from a circular focused, 2.25 MHz source, through single and multiple layered tissue mimicking fluids, for source pressures in the range from 13 kPa to 310 kPa. Two tissue mimicking fluids are developed to provide acoustic properties similar to amniotic fluid and a typical soft tissue. The values of the nonlinearity parameter, sound velocity and frequency dependence of attenuation for both fluids are presented, and the measurement procedures employed to obtain these characteristics are described in detail. These acoustic parameters, together with the measured source conditions are used as input to the numerical model, allowing the experimental conditions to be simulated. Extensive comparisons are made between the model's predictions and the axial pressure field measurements. Results are presented in the frequency domain showing the fundamental and three subsequent harmonic amplitudes on axis, as a function of axial distance. These show that significant nonlinear distortion can occur through media with characteristics typical of tissue. Time domain waveform comparisons are also made. An excellent agreement is found between theory and experiment indicating that the model can be used to predict nonlinear ultrasound propagation through multiple layers of tissue-like media. The numerical code is also used to model the

  11. Modelling human mobility patterns using photographic data shared online.

    Science.gov (United States)

    Barchiesi, Daniele; Preis, Tobias; Bishop, Steven; Moat, Helen Susannah

    2015-08-01

    Humans are inherently mobile creatures. The way we move around our environment has consequences for a wide range of problems, including the design of efficient transportation systems and the planning of urban areas. Here, we gather data about the position in space and time of about 16 000 individuals who uploaded geo-tagged images from locations within the UK to the Flickr photo-sharing website. Inspired by the theory of Lévy flights, which has previously been used to describe the statistical properties of human mobility, we design a machine learning algorithm to infer the probability of finding people in geographical locations and the probability of movement between pairs of locations. Our findings are in general agreement with official figures in the UK and on travel flows between pairs of major cities, suggesting that online data sources may be used to quantify and model large-scale human mobility patterns.

  12. Plants as models for the study of human pathogenesis.

    Science.gov (United States)

    Guttman, David S

    2004-05-01

    There are many common disease mechanisms used by bacterial pathogens of plants and humans. They use common means of attachment, secretion and genetic regulation. They share many virulence factors, such as extracellular polysaccharides and some type III secreted effectors. Plant and human innate immune systems also share many similarities. Many of these shared bacterial virulence mechanisms are homologous, but even more appear to have independently converged on a common function. This combination of homologous and analogous systems reveals conserved and critical steps in the disease process. Given these similarities, and the many experimental advantages of plant biology, including ease of replication, stringent genetic and reproductive control, and high throughput with low cost, it is proposed that plants would make excellent models for the study of human pathogenesis.

  13. Fuzzy Modelling for Human Dynamics Based on Online Social Networks.

    Science.gov (United States)

    Cuenca-Jara, Jesus; Terroso-Saenz, Fernando; Valdes-Vela, Mercedes; Skarmeta, Antonio F

    2017-08-24

    Human mobility mining has attracted a lot of attention in the research community due to its multiple implications in the provisioning of innovative services for large metropolises. In this scope, Online Social Networks (OSN) have arisen as a promising source of location data to come up with new mobility models. However, the human nature of this data makes it rather noisy and inaccurate. In order to deal with such limitations, the present work introduces a framework for human mobility mining based on fuzzy logic. Firstly, a fuzzy clustering algorithm extracts the most active OSN areas at different time periods. Next, such clusters are the building blocks to compose mobility patterns. Furthermore, a location prediction service based on a fuzzy rule classifier has been developed on top of the framework. Finally, both the framework and the predictor has been tested with a Twitter and Flickr dataset in two large cities.

  14. A Model of Representational Spaces in Human Cortex.

    Science.gov (United States)

    Guntupalli, J Swaroop; Hanke, Michael; Halchenko, Yaroslav O; Connolly, Andrew C; Ramadge, Peter J; Haxby, James V

    2016-06-01

    Current models of the functional architecture of human cortex emphasize areas that capture coarse-scale features of cortical topography but provide no account for population responses that encode information in fine-scale patterns of activity. Here, we present a linear model of shared representational spaces in human cortex that captures fine-scale distinctions among population responses with response-tuning basis functions that are common across brains and models cortical patterns of neural responses with individual-specific topographic basis functions. We derive a common model space for the whole cortex using a new algorithm, searchlight hyperalignment, and complex, dynamic stimuli that provide a broad sampling of visual, auditory, and social percepts. The model aligns representations across brains in occipital, temporal, parietal, and prefrontal cortices, as shown by between-subject multivariate pattern classification and intersubject correlation of representational geometry, indicating that structural principles for shared neural representations apply across widely divergent domains of information. The model provides a rigorous account for individual variability of well-known coarse-scale topographies, such as retinotopy and category selectivity, and goes further to account for fine-scale patterns that are multiplexed with coarse-scale topographies and carry finer distinctions. © The Author 2016. Published by Oxford University Press.

  15. Multivariate Models for Prediction of Human Skin Sensitization Hazard

    Science.gov (United States)

    Strickland, Judy; Zang, Qingda; Paris, Michael; Lehmann, David M.; Allen, David; Choksi, Neepa; Matheson, Joanna; Jacobs, Abigail; Casey, Warren; Kleinstreuer, Nicole

    2016-01-01

    One of ICCVAM’s top priorities is the development and evaluation of non-animal approaches to identify potential skin sensitizers. The complexity of biological events necessary to produce skin sensitization suggests that no single alternative method will replace the currently accepted animal tests. ICCVAM is evaluating an integrated approach to testing and assessment based on the adverse outcome pathway for skin sensitization that uses machine learning approaches to predict human skin sensitization hazard. We combined data from three in chemico or in vitro assays—the direct peptide reactivity assay (DPRA), human cell line activation test (h-CLAT), and KeratinoSens™ assay—six physicochemical properties, and an in silico read-across prediction of skin sensitization hazard into 12 variable groups. The variable groups were evaluated using two machine learning approaches, logistic regression (LR) and support vector machine (SVM), to predict human skin sensitization hazard. Models were trained on 72 substances and tested on an external set of 24 substances. The six models (three LR and three SVM) with the highest accuracy (92%) used: (1) DPRA, h-CLAT, and read-across; (2) DPRA, h-CLAT, read-across, and KeratinoSens; or (3) DPRA, h-CLAT, read-across, KeratinoSens, and log P. The models performed better at predicting human skin sensitization hazard than the murine local lymph node assay (accuracy = 88%), any of the alternative methods alone (accuracy = 63–79%), or test batteries combining data from the individual methods (accuracy = 75%). These results suggest that computational methods are promising tools to effectively identify potential human skin sensitizers without animal testing. PMID:27480324

  16. Marmosets: A Neuroscientific Model of Human Social Behavior

    Science.gov (United States)

    Freiwald, Winrich A; Leopold, David A; Mitchell, Jude F; Silva, Afonso C; Wang, Xiaoqin

    2016-01-01

    The common marmoset (Callithrix jacchus) has garnered interest recently as a powerful model for the future of neuroscience research. Much of this excitement has centered on the species’ reproductive biology and compatibility with gene editing techniques, which together have provided a path for transgenic marmosets to contribute to the study of disease as well as basic brain mechanisms. In step with technical advances is the need to establish experimental paradigms that optimally tap into the marmosets’ behavioral and cognitive capacities. While conditioned task performance of a marmoset can compare unfavorably with rhesus monkey performance on conventional testing paradigms, marmosets’ social cognition and communication are more similar to that of humans. For example, marmosets are amongst only a handful of primates that, like humans, routinely pair bond and care cooperatively for their young. They are also notably pro-social and exhibit social cognitive abilities, such as imitation, that are rare outside of the Apes. In this review, we describe key facets of marmoset natural social behavior and demonstrate that emerging behavioral paradigms are well suited to isolate components of marmoset cognition that are highly relevant to humans. These approaches generally embrace natural behavior and communication, which has been rare in conventional primate testing, and thus allow for a new consideration of neural mechanisms underlying primate social cognition and communication. We anticipate that through parallel technical and paradigmatic advances, marmosets will become an essential model of human social behavior, including its dysfunction in nearly all neuropsychiatric disorders. PMID:27100195

  17. Multilayer modeling and analysis of human brain networks

    Science.gov (United States)

    2017-01-01

    Abstract Understanding how the human brain is structured, and how its architecture is related to function, is of paramount importance for a variety of applications, including but not limited to new ways to prevent, deal with, and cure brain diseases, such as Alzheimer’s or Parkinson’s, and psychiatric disorders, such as schizophrenia. The recent advances in structural and functional neuroimaging, together with the increasing attitude toward interdisciplinary approaches involving computer science, mathematics, and physics, are fostering interesting results from computational neuroscience that are quite often based on the analysis of complex network representation of the human brain. In recent years, this representation experienced a theoretical and computational revolution that is breaching neuroscience, allowing us to cope with the increasing complexity of the human brain across multiple scales and in multiple dimensions and to model structural and functional connectivity from new perspectives, often combined with each other. In this work, we will review the main achievements obtained from interdisciplinary research based on magnetic resonance imaging and establish de facto, the birth of multilayer network analysis and modeling of the human brain. PMID:28327916

  18. Multimodal, 3D pathology-mimicking bladder phantom for evaluation of cystoscopic technologies (Conference Presentation)

    Science.gov (United States)

    Smith, Gennifer T.; Lurie, Kristen L.; Zlatev, Dimitar V.; Liao, Joseph C.; Ellerbee, Audrey K.

    2016-02-01

    Optical coherence tomography (OCT) and blue light cystoscopy (BLC) have shown significant potential as complementary technologies to traditional white light cystoscopy (WLC) for early bladder cancer detection. Three-dimensional (3D) organ-mimicking phantoms provide realistic imaging environments for testing new technology designs, the diagnostic potential of systems, and novel image processing algorithms prior to validation in real tissue. Importantly, the phantom should mimic features of healthy and diseased tissue as they appear under WLC, BLC, and OCT, which are sensitive to tissue color and structure, fluorescent contrast, and optical scattering of subsurface layers, respectively. We present a phantom posing the hollow shape of the bladder and fabricated using a combination of 3D-printing and spray-coating with Dragon Skin (DS) (Smooth-On Inc.), a highly elastic polymer to mimic the layered structure of the bladder. Optical scattering of DS was tuned by addition of titanium dioxide, resulting in scattering coefficients sufficient to cover the human bladder range (0.49 to 2.0 mm^-1). Mucosal vasculature and tissue coloration were mimicked with elastic cord and red dye, respectively. Urethral access was provided through a small hole excised from the base of the phantom. Inserted features of bladder pathology included altered tissue color (WLC), fluorescence emission (BLC), and variations in layered structure (OCT). The phantom surface and underlying material were assessed on the basis of elasticity, optical scattering, layer thicknesses, and qualitative image appearance. WLC, BLC, and OCT images of normal and cancerous features in the phantom qualitatively matched corresponding images from human bladders.

  19. Human Factors Engineering Review Model for advanced nuclear power reactors

    International Nuclear Information System (INIS)

    O'Hara, J.; Higgins, J.; Goodman, C.; Galletti, G.: Eckenrode, R.

    1993-01-01

    One of the major issues to emerge from the initial design reviews under the certification process was that detailed human-systems interface (HSI) design information was not available for staff review. To address the lack of design detail issue. The Nuclear Regulatory Commission (NRC) is performing the design certification reviews based on a design process plan which describes the human factors engineering (HFE) program elements that are necessary and sufficient to develop an acceptable detailed design specification. Since the review of a design process is unprecedented in the nuclear industry. The criteria for review are not addressed by current regulations or guidance documents and. therefore, had to be developed. Thus, an HFE Program Review Model was developed. This paper will describe the model's rationale, scope, objectives, development, general characteristics. and application

  20. A family of hyperelastic models for human brain tissue

    Science.gov (United States)

    Mihai, L. Angela; Budday, Silvia; Holzapfel, Gerhard A.; Kuhl, Ellen; Goriely, Alain

    2017-09-01

    Experiments on brain samples under multiaxial loading have shown that human brain tissue is both extremely soft when compared to other biological tissues and characterized by a peculiar elastic response under combined shear and compression/tension: there is a significant increase in shear stress with increasing axial compression compared to a moderate increase with increasing axial tension. Recent studies have revealed that many widely used constitutive models for soft biological tissues fail to capture this characteristic response. Here, guided by experiments of human brain tissue, we develop a family of modeling approaches that capture the elasticity of brain tissue under varying simple shear superposed on varying axial stretch by exploiting key observations about the behavior of the nonlinear shear modulus, which can be obtained directly from the experimental data.