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Sample records for accessory function differential

  1. Accessory spleen: differential diagnosis for lymphoma in autoimmune lymphoproliferative syndrome.

    PubMed

    Georgin-Lavialle, Sophie; Aouba, Achille; Canioni, Danielle; Rieux-Laucat, Frédéric; Fischer, Alain; Hermine, Olivier

    2010-07-01

    Mutations of Fas or, less frequently, Fas ligand genes result in a rare inherited lymphoid disorder called autoimmune lymphoproliferative syndrome (ALPS) in which lymphoma frequency is increased. We report on a patient with ALPS who had been splenectomized for giant splenomegaly and progressively developed a voluminous abdominal tumor. The histology of the removed tumor revealed that it was an accessory spleen exhibiting typical features of ALPS involvement, as shown by the presence of a large excess of CD3+CD4-CD8- T cells and plasma cells without a detectable monoclonal population. This observation highlights the lymphoma's differential diagnosis in this context.

  2. Segregated pathways to the vomeronasal amygdala: differential projections from the anterior and posterior divisions of the accessory olfactory bulb.

    PubMed

    Mohedano-Moriano, Alicia; Pro-Sistiaga, Palma; Ubeda-Bañón, Isabel; Crespo, Carlos; Insausti, Ricardo; Martinez-Marcos, Alino

    2007-04-01

    Apically and basally located receptor neurons in the vomeronasal sensory epithelium express G(i2 alpha)- and G(o alpha)-proteins, V1R and V2R vomeronasal receptors, project to the anterior and posterior accessory olfactory bulb and respond to different stimuli, respectively. The extent to which secondary projections from the two portions of the accessory olfactory bulb are convergent in the vomeronasal amygdala is controversial. This issue is addressed by using anterograde and retrograde tract-tracing methods in rats including electron microscopy. Injections of dextran-amines, Fluoro Gold, cholera toxin-B subunit and Fast Blue were delivered to the anterior and posterior accessory olfactory bulb, bed nucleus of the stria terminalis, dorsal anterior amygdala and bed nucleus of the accessory olfactory tract/anteroventral medial amygdaloid nucleus. We have demonstrated that, apart from common vomeronasal-recipient areas, only the anterior accessory olfactory bulb projects to the bed nucleus of the stria terminalis, medial division, posteromedial part, and only the posterior accessory olfactory bulb projects to the dorsal anterior amygdala and deep cell layers of the bed nucleus of the accessory olfactory tract and the anteroventral medial amygdaloid nucleus. These results provide evidence that, excluding areas of convergence, the V1R and V2R vomeronasal pathways project to specific areas of the amygdala. These two vomeronasal subsystems are therefore anatomically and functionally separated in the telencephalon.

  3. Carotenoid-binding proteins; accessories to carotenoid function.

    PubMed

    Pilbrow, Jodi; Garama, Daniel; Carne, Alan

    2012-01-01

    Understanding of the widespread biological importance of carotenoids is increasing. Accompanying this is the developing recognition that the interaction of carotenoids with other molecules, such as proteins, is also essential. Here the significance of carotenoid-protein interactions with respect to biological function is reviewed for three well characterised carotenoprotein complexes; crustacyanin, the orange carotenoid protein and glutathione-S-transferase P1. In addition a preliminary report is made on the recent partial purification of an echinenone-binding protein extracted from a New Zealand sea urchin, Evechinus chloroticus.

  4. Gallium arsenide exposure impairs splenic B cell accessory function.

    PubMed

    Gondre-Lewis, Timothy A; Hartmann, Constance B; Caffrey, Rebecca E; McCoy, Kathleen L

    2003-03-01

    Gallium arsenide (GaAs) is utilized in industries for its semiconductor and optical properties. Chemical exposure of animals systemically suppresses several immune functions. The ability of splenic B cells to activate antigen-specific helper CD4(+) T cell hybridomas was assessed, and various aspects of antigen-presenting cell function were examined. GaAs-exposed murine B cells were impaired in processing intact soluble protein antigens, and the defect was antigen dependent. In contrast, B cells after exposure competently presented peptides to the T cells, which do not require processing. Cell surface expression of major histocompatibility complex (MHC) class II molecules and several costimulatory molecules on splenic B cells, which are critical for helper T cell activation, was not affected by chemical exposure. GaAs exposure also did not influence the stability of MHC class II heterodimers, suggesting that the defect may precede peptide exchange. GaAs-exposed B cells contained a normal level of aspartyl cathepsin activity; however, proteolytic activities of thiol cathepsins B and L were approximately half the control levels. Furthermore, two cleavage fragments of invariant chain, a molecular chaperone of MHC class II molecules, were increased in GaAs-exposed B cells, indicative of defective degradation. Thus, diminished thiol proteolytic activity in B cells may be responsible for their impaired antigen processing and invariant chain degradation, which may contribute to systemic immunosuppression caused by GaAs exposure.

  5. Accessory subunits are integral for assembly and function of human mitochondrial complex I.

    PubMed

    Stroud, David A; Surgenor, Elliot E; Formosa, Luke E; Reljic, Boris; Frazier, Ann E; Dibley, Marris G; Osellame, Laura D; Stait, Tegan; Beilharz, Traude H; Thorburn, David R; Salim, Agus; Ryan, Michael T

    2016-10-06

    Complex I (NADH:ubiquinone oxidoreductase) is the first enzyme of the mitochondrial respiratory chain and is composed of 45 subunits in humans, making it one of the largest known multi-subunit membrane protein complexes. Complex I exists in supercomplex forms with respiratory chain complexes III and IV, which are together required for the generation of a transmembrane proton gradient used for the synthesis of ATP. Complex I is also a major source of damaging reactive oxygen species and its dysfunction is associated with mitochondrial disease, Parkinson's disease and ageing. Bacterial and human complex I share 14 core subunits that are essential for enzymatic function; however, the role and necessity of the remaining 31 human accessory subunits is unclear. The incorporation of accessory subunits into the complex increases the cellular energetic cost and has necessitated the involvement of numerous assembly factors for complex I biogenesis. Here we use gene editing to generate human knockout cell lines for each accessory subunit. We show that 25 subunits are strictly required for assembly of a functional complex and 1 subunit is essential for cell viability. Quantitative proteomic analysis of cell lines revealed that loss of each subunit affects the stability of other subunits residing in the same structural module. Analysis of proteomic changes after the loss of specific modules revealed that ATP5SL and DMAC1 are required for assembly of the distal portion of the complex I membrane arm. Our results demonstrate the broad importance of accessory subunits in the structure and function of human complex I. Coupling gene-editing technology with proteomics represents a powerful tool for dissecting large multi-subunit complexes and enables the study of complex dysfunction at a cellular level.

  6. Differential Objective Function.

    ERIC Educational Resources Information Center

    Kino, Mary M.; And Others

    Item response theory (IRT) has been used extensively to study differential item functioning (dif) and to identify potentially biased items. The use of IRT for diagnostic purposes is less prevalent and has received comparatively less attention. This study addressed differential objective function (dof) to identify potentially biased content units.…

  7. Differential Localization of the Streptococcal Accessory Sec Components and Implications for Substrate Export

    PubMed Central

    Yen, Yihfen T.; Cameron, Todd A.; Bensing, Barbara A.; Seepersaud, Ravin; Zambryski, Patricia C.

    2013-01-01

    The accessory Sec system of Streptococcus gordonii is comprised of SecY2, SecA2, and five proteins (Asp1 through -5) that are required for the export of a serine-rich glycoprotein, GspB. We have previously shown that a number of the Asps interact with GspB, SecA2, or each other. To further define the roles of these Asps in export, we examined their subcellular localization in S. gordonii and in Escherichia coli expressing the streptococcal accessory Sec system. In particular, we assessed how the locations of these accessory Sec proteins were altered by the presence of other components. Using fluorescence microscopy, we found in E. coli that SecA2 localized within multiple foci at the cell membrane, regardless of whether other accessory Sec proteins were expressed. Asp2 alone localized to the cell poles but formed a similar punctate pattern at the membrane when SecA2 was present. Asp1 and Asp3 localized diffusely in the cytosol when expressed alone or with SecA2. However, these proteins redistributed to the membrane in a punctate arrangement when all of the accessory Sec components were present. Cell fractionation studies with S. gordonii further corroborated these microscopy results. Collectively, these findings indicate that Asp1 to -3 are not integral membrane proteins that form structural parts of the translocation channel. Instead, SecA2 serves as a docking site for Asp2, which in turn attracts a complex of Asp1 and Asp3 to the membrane. These protein interactions may be important for the trafficking of GspB to the cell membrane and its subsequent translocation. PMID:23204472

  8. Functional characterisation of a TLR accessory protein, UNC93B1, in Atlantic salmon (Salmo salar).

    PubMed

    Lee, P T; Zou, J; Holland, J W; Martin, S A M; Scott, C J W; Kanellos, T; Secombes, C J

    2015-05-01

    Toll-like receptors (TLRs) are indispensable components of the innate immune system, which recognise conserved pathogen associated molecular patterns (PAMPs) and induce a series of defensive immune responses to protect the host. Biosynthesis, localisation and activation of TLRs are dependent on TLR accessory proteins. In this study, we identified the accessory protein, UNC93B1, from Atlantic salmon (Salmo salar) whole-genome shotgun (WGS) contigs aided by the conserved gene synteny of genes flanking UNC93B1 in fish, birds and mammals. Phylogenetic analysis showed that salmon UNC93B1 grouped with other vertebrate UNC93B1 molecules, and had highest amino acid identity and similarity to zebrafish UNC93B1. The salmon UNC93B1 gene organisation was also similar in structure to mammalian UNC93B1. Our gene expression studies revealed that salmon UNC93B1 was more highly expressed in spleen, liver and gill tissues but was expressed at a lower level in head kidney tissue in post-smolts relative to parr. Moreover, salmon UNC93B1 mRNA transcripts were up-regulated in vivo in spleen tissue from polyI:C treated salmon and in vitro in polyI:C or IFNγ stimulated Salmon Head Kidney-1 (SHK-1) cells. Initial studies into the functional role of salmon UNC93B1 in fish TLR signalling found that both wild type salmon UNC93B1 and a molecule with a site-directed mutation (H424R) co-immunoprecipitated with salmon TLR19, TLR20a and TLR20d. Overall, these data illustrate the potential importance of UNC93B1 as an accessory protein in fish TLR signalling.

  9. Functional Assembly of Accessory Optic System Circuitry Critical for Compensatory Eye Movements

    PubMed Central

    Sun, Lu O.; Brady, Colleen M.; Cahill, Hugh; Al-Khindi, Timour; Sakuta, Hiraki; Dhande, Onkar S.; Noda, Masaharu; Huberman, Andrew D.; Nathans, Jeremy; Kolodkin, Alex L.

    2015-01-01

    SUMMARY Accurate motion detection requires neural circuitry that compensates for global visual field motion. Select subtypes of retinal ganglion cells perceive image motion and connect to the accessory optic system (AOS) in the brain, which generates compensatory eye movements that stabilize images during slow visual field motion. Here, we show that the murine transmembrane semaphorin 6A (Sema6A) is expressed in a subset of On direction-selective ganglion cells (On DSGCs) and is required for retinorecipient axonal targeting to the medial terminal nucleus (MTN) of the AOS. Plexin A2 and A4, two Sema6A binding partners, are expressed in MTN cells, attract Sema6A+ On DSGC axons, and mediate MTN targeting of Sema6A+ RGC projections. Furthermore, Sema6A/Plexin-A2/A4 signaling is required for the functional output of the AOS. These data reveal molecular mechanisms underlying the assembly of AOS circuits critical for moving image perception. PMID:25959730

  10. Prevention of ultraviolet radiation-induced suppression of accessory cell function of Langerhans cells by Aloe vera gel components.

    PubMed

    Lee, C K; Han, S S; Mo, Y K; Kim, R S; Chung, M H; Park, Y I; Lee, S K; Kim, Y S

    1997-10-01

    The active components of Aloe vera gel that can prevent ultraviolet B (UVB)-induced suppression of accessory cell function of Langerhans cells (LC) were purified by activity-guided sequential fractionation followed by in vitro functional assay. The functional assay was based on the fact that exposure of freshly isolated murine epidermal cells (EC) to UVB radiation resulted in impairment of accessory cell function of LC, as measured by their ability to support anti-CD3 monoclonal antibody (mAb)-primed T-cell mitogenesis. This UVB-suppressed LC accessory cell function was prevented by addition of partially purified Aloe gel components to cultures of UVB-irradiated EC. The Aloe gel components appeared to prevent events occurring within the first 24 h after UVB irradiation that lead to the impairment of accessory cell function. The Aloe gel components did not cause proliferation of anti-CD3 mAb-primed T-cells, nor did induce proliferation of normal EC. The activity-guided final purification of Aloe gel components resulted in the isolation of two components. Both of the components were small molecular weight (MW) substances with an apparent MW of less than 1,000 Da but different from each other in net charge characteristics at pH 7.4. These results suggest that Aloe vera gel contains at least two small molecular weight immunomodulators that may prevent UVB-induced immune suppression in the skin.

  11. Cloning, expression, and functional characterization of the equine herpesvirus 1 DNA polymerase and its accessory subunit.

    PubMed

    Loregian, Arianna; Case, Alessandro; Cancellotti, Enrico; Valente, Carlo; Marsden, Howard S; Palù, Giorgio

    2006-07-01

    We report the expression and characterization of the putative catalytic subunit (pORF30) and accessory protein (pORF18) of equine herpesvirus 1 DNA polymerase, which are encoded by open reading frames 30 and 18 and are homologous to herpes simplex virus type 1 UL30 and UL42, respectively. In vitro transcription-translation of open reading frames 30 and 18 generated proteins of 136 and 45 kDa, respectively. In vitro-expressed pORF30 possessed basal DNA polymerase activity that was stimulated by pORF18, as measured by DNA polymerase assays in vitro. Purified baculovirus-expressed pORF30 exhibited DNA polymerase activity similar to that of the in vitro-expressed protein, and baculovirus-expressed pORF18 could stimulate both nucleotide incorporation and long-chain DNA synthesis by pORF30 in a dose- and time-dependent manner. The salt optima for activity of both pORF30 and the holoenzyme were substantially different from those for other herpesvirus DNA polymerases. As demonstrated by yeast two-hybrid assays, pORF30 and pORF18 could physically interact, most likely with a 1:1 stoichiometry. Finally, by mutational analysis of the 1,220-residue pORF30, we demonstrated that the extreme C terminus of pORF30 is important for physical and functional interaction with the accessory protein, as reported for UL30 and other herpesvirus DNA polymerases. In addition, a C-proximal region of pORF30, corresponding to residues 1114 to 1172, is involved in binding to, and stimulation by, pORF18. Taken together, the results indicate that pORF30 and pORF18 are the equine herpesvirus 1 counterparts of herpes simplex virus type 1 UL30 and UL42 and share many, but not all, of their characteristics.

  12. Versatile Roles of V-ATPases Accessory Subunit Ac45 in Osteoclast Formation and Function

    PubMed Central

    Lin, Zhen; Pavlos, Nathan J.; Jiang, Qing; Xu, Jiake; Dai, Ke R.; Zheng, Ming H.

    2011-01-01

    Vacuolar-type H+-ATPases (V-ATPases) are macromolecular proton pumps that acidify intracellular cargos and deliver protons across the plasma membrane of a variety of specialized cells, including bone-resorbing osteoclasts. Extracellular acidification is crucial for osteoclastic bone resorption, a process that initiates the dissolution of mineralized bone matrix. While the importance of V-ATPases in osteoclastic resorptive function is well-defined, whether V-ATPases facilitate additional aspects of osteoclast function and/or formation remains largely obscure. Here we report that the V-ATPase accessory subunit Ac45 participates in both osteoclast formation and function. Using a siRNA-based approach, we show that targeted suppression of Ac45 impairs intracellular acidification and endocytosis, both are prerequisite for osteoclastic bone resorptive function in vitro. Interestingly, we find that knockdown of Ac45 also attenuates osteoclastogenesis owing to a reduced fusion capacity of osteoclastic precursor cells. Finally, in an effort to gain more detailed insights into the functional role of Ac45 in osteoclasts, we attempted to generate osteoclast-specific Ac45 conditional knockout mice using a Cathepsin K-Cre-LoxP system. Surprisingly, however, insertion of the neomycin cassette in the Ac45-FloxNeo mice resulted in marked disturbances in CNS development and ensuing embryonic lethality thus precluding functional assessment of Ac45 in osteoclasts and peripheral bone tissues. Based on these unexpected findings we propose that, in addition to its canonical function in V-ATPase-mediated acidification, Ac45 plays versatile roles during osteoclast formation and function. PMID:22087256

  13. Neoplastic cells obtained from Hodgkin's disease function as accessory cells for mitogen-induced human T cell proliferative responses.

    PubMed

    Fisher, R I; Bates, S E; Bostick-Bruton, F; Tuteja, N; Diehl, V

    1984-05-01

    Purified human peripheral blood T cells that have been depleted of Ia-bearing cells and adherent cells do not proliferate in response to concanavalin A. The addition of as few as 1% radiated L428 tumor cells restores the proliferative capacity of the T cells. The L428 cell line is a long-term tissue culture line of Reed-Sternberg cells obtained from a patient with Hodgkin's disease. The proliferation of the T cells plus the L428 cells follows the same kinetics and has the same response to varying doses of mitogen as either unfractionated mononuclear leukocytes or purified T cells plus allogeneic adherent cells. The L428 cells are 30 times more potent as accessory cells than allogeneic adherent cells. The accessory cell function of the L428 cells is not blocked in cultures containing anti-Ia antibody. Neither supernatant from the L428 cell cultures nor human IL 1 replaces the accessory cells. The ability of the L428 cells to restore the proliferative capacity of purified T cells isolated from patients with active Hodgkin's disease was also studied. Patients with early stages of the disease had normal proliferative responses in the presence of the L428 accessory cells. However, the proliferative response of the poor prognosis, advanced-stage patients was reduced as compared to age- and sex-matched controls, supporting a deficit in their T cell function. The L428 tumor cells share many properties such as accessory cell function, morphology, and cell surface markers with the dendritic cells described in animal and human systems.

  14. Using Differentials to Differentiate Trigonometric and Exponential Functions

    ERIC Educational Resources Information Center

    Dray, Tevian

    2013-01-01

    Starting from geometric definitions, we show how differentials can be used to differentiate trigonometric and exponential functions without limits, numerical estimates, solutions of differential equations, or integration.

  15. Shared and differential traits in the accessory olfactory bulb of caviomorph rodents with particular reference to the semiaquatic capybara

    PubMed Central

    Suárez, Rodrigo; Santibáñez, Rodrigo; Parra, Daniela; Coppi, Antonio A; Abrahão, Luciana M B; Sasahara, Tais H C; Mpodozis, Jorge

    2011-01-01

    The vomeronasal system is crucial for social and sexual communication in mammals. Two populations of vomeronasal sensory neurons, each expressing Gαi2 or Gαo proteins, send projections to glomeruli of the rostral or caudal accessory olfactory bulb, rAOB and cAOB, respectively. In rodents, the Gαi2- and Gαo-expressing vomeronasal pathways have shown differential responses to small/volatile vs. large/non-volatile semiochemicals, respectively. Moreover, early gene expression suggests predominant activation of rAOB and cAOB neurons in sexual vs. aggressive contexts, respectively. We recently described the AOB of Octodon degus, a semiarid-inhabiting diurnal caviomorph. Their AOB has a cell indentation between subdomains and the rAOB is twice the size of the cAOB. Moreover, their AOB receives innervation from the lateral aspect, contrasting with the medial innervation of all other mammals examined to date. Aiming to relate AOB anatomy with lifestyle, we performed a morphometric study on the AOB of the capybara, a semiaquatic caviomorph whose lifestyle differs remarkably from that of O. degus. Capybaras mate in water and scent-mark their surroundings with oily deposits, mostly for male–male communication. We found that, similar to O. degus, the AOB of capybaras shows a lateral innervation of the vomeronasal nerve, a cell indentation between subdomains and heterogeneous subdomains, but in contrast to O. degus the caudal portion is larger than the rostral one. We also observed that four other caviomorph species present a lateral AOB innervation and a cell indentation between AOB subdomains, suggesting that those traits could represent apomorphies of the group. We propose that although some AOB traits may be phylogenetically conserved in caviomorphs, ecological specializations may play an important role in shaping the AOB. PMID:21457258

  16. Shared and differential traits in the accessory olfactory bulb of caviomorph rodents with particular reference to the semiaquatic capybara.

    PubMed

    Suárez, Rodrigo; Santibáñez, Rodrigo; Parra, Daniela; Coppi, Antonio A; Abrahão, Luciana M B; Sasahara, Tais H C; Mpodozis, Jorge

    2011-05-01

    The vomeronasal system is crucial for social and sexual communication in mammals. Two populations of vomeronasal sensory neurons, each expressing Gαi2 or Gαo proteins, send projections to glomeruli of the rostral or caudal accessory olfactory bulb, rAOB and cAOB, respectively. In rodents, the Gαi2- and Gαo-expressing vomeronasal pathways have shown differential responses to small/volatile vs. large/non-volatile semiochemicals, respectively. Moreover, early gene expression suggests predominant activation of rAOB and cAOB neurons in sexual vs. aggressive contexts, respectively. We recently described the AOB of Octodon degus, a semiarid-inhabiting diurnal caviomorph. Their AOB has a cell indentation between subdomains and the rAOB is twice the size of the cAOB. Moreover, their AOB receives innervation from the lateral aspect, contrasting with the medial innervation of all other mammals examined to date. Aiming to relate AOB anatomy with lifestyle, we performed a morphometric study on the AOB of the capybara, a semiaquatic caviomorph whose lifestyle differs remarkably from that of O. degus. Capybaras mate in water and scent-mark their surroundings with oily deposits, mostly for male-male communication. We found that, similar to O. degus, the AOB of capybaras shows a lateral innervation of the vomeronasal nerve, a cell indentation between subdomains and heterogeneous subdomains, but in contrast to O. degus the caudal portion is larger than the rostral one. We also observed that four other caviomorph species present a lateral AOB innervation and a cell indentation between AOB subdomains, suggesting that those traits could represent apomorphies of the group. We propose that although some AOB traits may be phylogenetically conserved in caviomorphs, ecological specializations may play an important role in shaping the AOB.

  17. Functional anatomy of the accessory nerve studied through intraoperative electrophysiological mapping.

    PubMed

    Brînzeu, Andrei; Sindou, Marc

    2017-03-01

    OBJECTIVE Classically the 11th cranial nerve (CN XI, or accessory nerve) is described as having a cranial and a spinal root, the latter arising from the upper segments of the spinal cord through a number of very fine rootlets. According to classical knowledge, the cranial root gives motor innervation to the vocal cords, whereas the spinal root provides the motor innervation of the sternocleidomastoid muscle (SCM) and of the upper portions of the trapezius muscle (TZ). The specific function of each of the rootlets of the spinal component is not well known. Therefore the authors aimed to map, using intraoperative direct electrical stimulation and electromyographic (EMG) recordings, the innervation territory of these rootlets in relation to their exit level from the CNS. METHODS Forty-nine patients undergoing surgery with intradural exposure at the craniocervical junction were enrolled in the study. The EMG recordings included the sternal and clavicular parts of the SCM (SCM-S and SCM-C), the superior and middle parts of the TZ (TZ-S and TZ-M), and whenever possible the vocal cords. The main trunk of CN XI, its roots (both cranial and spinal), and when possible the fine cervical rootlets, were stimulated at predetermined locations, from the jugular foramen down to the lowest cervical level exposed. The EMG responses were collected, and a map of the responses was drawn up. RESULTS Monitoring and stimulation of the spinal root were performed in all cases, whereas for the cranial root this was possible in only 19 cases. A total of 262 stimulation sites were explored: 70 at the common trunk of the nerve, 19 at the cranial root, 136 at various levels on the spinal root, and 37 at the cervical rootlets. A vocal cord response was obtained by stimulation of the cranial root in 84.2% (16/19); absence of response was considered to have a technical origin. In no case did the vocal cords respond to the stimulation of the spinal root or rootlets. Stimulation of the cervical

  18. Accessory Olfactory Bulb Function is Modulated by Input from the Main Olfactory Epithelium

    PubMed Central

    Slotnick, Burton; Restrepo, Diego; Schellinck, Heather; Archbold, Georgina; Price, Stephen; Lin, Weihong

    2013-01-01

    While it is now established that sensory neurons in both the main olfactory epithelium and the vomeronasal organ may be activated by both general and pheromonal odorants, it remains unclear what initiates sampling by the VNO. Anterograde transport of wheat germ agglutinin-horseradish peroxidase was used to determine that adequate intranasal syringing with zinc sulfate interrupted all inputs to the main olfactory bulb but left intact those to the accessory olfactory bulb. Adult male treated mice were frankly anosmic when tested with pheromonal and non-pheromonal odors and failed to engage in aggressive behavior. Treated juvenile females failed to show puberty acceleration subsequent to exposure to bedding from adult males. Activation of the immediate early gene c-Fos and electro-vomeronasogram recording confirmed the integrity of the vomeronasal system in zinc sulfate treated mice. These results support the hypothesis that odor detection by the main olfactory epithelium is required to initiate sampling by the vomeronasal system. PMID:20377623

  19. Accessory olfactory bulb function is modulated by input from the main olfactory epithelium.

    PubMed

    Slotnick, Burton; Restrepo, Diego; Schellinck, Heather; Archbold, Georgina; Price, Stephen; Lin, Weihong

    2010-03-01

    Although it is now established that sensory neurons in both the main olfactory epithelium and the vomeronasal organ may be activated by both general and pheromonal odorants, it remains unclear what initiates sampling by the vomeronasal organ. Anterograde transport of wheat germ agglutinin-horseradish peroxidase was used to determine that adequate intranasal syringing with zinc sulfate interrupted all inputs to the main olfactory bulb but left intact those to the accessory olfactory bulb. Adult male treated mice were frankly anosmic when tested with pheromonal and non-pheromonal odors and failed to engage in aggressive behavior. Treated juvenile females failed to show puberty acceleration subsequent to exposure to bedding from adult males. Activation of the immediate early gene c-Fos and electrovomeronasogram recording confirmed the integrity of the vomeronasal system in zinc sulfate-treated mice. These results support the hypothesis that odor detection by the main olfactory epithelium is required to initiate sampling by the vomeronasal system.

  20. Optogenetic Activation of Accessory Olfactory Bulb Input to the Forebrain Differentially Modulates Investigation of Opposite versus Same-Sex Urinary Chemosignals and Stimulates Mating in Male Mice.

    PubMed

    Kunkhyen, Tenzin; McCarthy, Elizabeth A; Korzan, Wayne J; Doctor, Danielle; Han, Xue; Baum, Michael J; Cherry, James A

    2017-01-01

    Surgical or genetic disruption of vomeronasal organ (VNO)-accessory olfactory bulb (AOB) function previously eliminated the ability of male mice to processes pheromones that elicit territorial behavior and aggression. By contrast, neither disruption significantly affected mating behaviors, although VNO lesions reduced males' investigation of nonvolatile female pheromones. We explored the contribution of VNO-AOB pheromonal processing to male courtship using optogenetic activation of AOB projections to the forebrain. Protocadherin-Cre male transgenic mice received bilateral AOB infections with channelrhodopsin2 (ChR2) viral vectors, and an optical fiber was implanted above the AOB. In olfactory choice tests, males preferred estrous female urine (EFU) over water; however, this preference was eliminated when diluted (5%) EFU was substituted for 100% EFU. Optogenetic AOB activation concurrent with nasal contact significantly augmented males' investigation compared to 5% EFU alone. Conversely, concurrent optogenetic AOB activation significantly reduced males' nasal investigation of diluted urine from gonadally intact males (5% IMU) compared to 5% IMU alone. These divergent effects of AOB optogenetic activation were lost when males were prevented from making direct nasal contact. Optogenetic AOB stimulation also failed to augment males' nasal investigation of deionized water or of food odors. Finally, during mating tests, optogenetic AOB stimulation delivered for 30 s when the male was in physical contact with an estrous female significantly facilitated the occurrence of penile intromission. Our results suggest that VNO-AOB signaling differentially modifies males' motivation to seek out female vs male urinary pheromones while augmenting males' sexual arousal leading to intromission and improved reproductive performance.

  1. Optogenetic Activation of Accessory Olfactory Bulb Input to the Forebrain Differentially Modulates Investigation of Opposite versus Same-Sex Urinary Chemosignals and Stimulates Mating in Male Mice

    PubMed Central

    McCarthy, Elizabeth A.; Korzan, Wayne J.; Doctor, Danielle; Han, Xue; Baum, Michael J.

    2017-01-01

    Abstract Surgical or genetic disruption of vomeronasal organ (VNO)-accessory olfactory bulb (AOB) function previously eliminated the ability of male mice to processes pheromones that elicit territorial behavior and aggression. By contrast, neither disruption significantly affected mating behaviors, although VNO lesions reduced males’ investigation of nonvolatile female pheromones. We explored the contribution of VNO-AOB pheromonal processing to male courtship using optogenetic activation of AOB projections to the forebrain. Protocadherin-Cre male transgenic mice received bilateral AOB infections with channelrhodopsin2 (ChR2) viral vectors, and an optical fiber was implanted above the AOB. In olfactory choice tests, males preferred estrous female urine (EFU) over water; however, this preference was eliminated when diluted (5%) EFU was substituted for 100% EFU. Optogenetic AOB activation concurrent with nasal contact significantly augmented males’ investigation compared to 5% EFU alone. Conversely, concurrent optogenetic AOB activation significantly reduced males’ nasal investigation of diluted urine from gonadally intact males (5% IMU) compared to 5% IMU alone. These divergent effects of AOB optogenetic activation were lost when males were prevented from making direct nasal contact. Optogenetic AOB stimulation also failed to augment males’ nasal investigation of deionized water or of food odors. Finally, during mating tests, optogenetic AOB stimulation delivered for 30 s when the male was in physical contact with an estrous female significantly facilitated the occurrence of penile intromission. Our results suggest that VNO-AOB signaling differentially modifies males’ motivation to seek out female vs male urinary pheromones while augmenting males’ sexual arousal leading to intromission and improved reproductive performance. PMID:28374006

  2. Dietary n-3 PUFA affect TcR-mediated activation of purified murine T cells and accessory cell function in co-cultures

    PubMed Central

    CHAPKIN, R S; ARRINGTON, J L; APANASOVICH, T V; CARROLL, R J; MCMURRAY, D N

    2002-01-01

    Diets enriched in n-3 polyunsaturated fatty acids (PUFA) suppress several functions of murine splenic T cells by acting directly on the T cells and/or indirectly on accessory cells. In this study, the relative contribution of highly purified populations of the two cell types to the dietary suppression of T cell function was examined. Mice were fed diets containing different levels of n-3 PUFA; safflower oil (SAF; control containing no n-3 PUFA), fish oil (FO) at 2% and 4%, or 1% purified docosahexaenoic acid (DHA) for 2 weeks. Purified (>90%) T cells were obtained from the spleen, and accessory cells (>95% adherent, esterase-positive) were obtained by peritoneal lavage. Purified T cells or accessory cells from each diet group were co-cultured with the alternative cell type from every other diet group, yielding a total of 16 different co-culture combinations. The T cells were stimulated with either concanavalin A (ConA) or antibodies to the T cell receptor (TcR)/CD3 complex and the costimulatory molecule CD28 (αCD3/αCD28), and proliferation was measured after four days. Suppression of T cell proliferation in the co-cultures was dependent upon the dose of dietary n-3 PUFA fed to mice from which the T cells were derived, irrespective of the dietary treatment of accessory cell donors. The greatest dietary effect was seen in mice consuming the DHA diet (P = 0·034 in the anova; P = 0·0053 in the Trend Test), and was observed with direct stimulation of the T cell receptor and CD28 costimulatory ligand, but not with ConA. A significant dietary effect was also contributed accessory cells (P = 0·033 in the Trend Test). We conclude that dietary n-3 PUFA affect TcR-mediated by T cell activation by both direct and indirect (accessory cell) mechanisms. PMID:12296847

  3. Accessory nerve palsy.

    PubMed

    Olarte, M; Adams, D

    1977-11-01

    After apparently uncomplicated excision of benign lesions in the posterior cervical triangle, two patients had shoulder pain. In one, neck pain and trapezius weakness were not prominent until one month after surgery. Inability to elevate the arm above the horizontal without externally rotating it, and prominent scapular displacement on arm abduction, but not on forward pushing movements, highlighted the trapezius dysfunction and differentiated it from serratus anterior weakness. Spinal accessory nerve lesions should be considered when minor surgical procedures, lymphadenitis, minor trauma, or tumours involved the posterior triangle of the neck.

  4. Surgical and conservative methods for restoring impaired motor function - facial nerve, spinal accessory nerve, hypoglossal nerve (not including vagal nerve or swallowing)

    PubMed Central

    Laskawi, R.; Rohrbach, S.

    2005-01-01

    The present review gives a survey of rehabilitative measures for disorders of the motor function of the mimetic muscles (facial nerve), and muscles innervated by the spinal accessory and hypoglossal nerves. The dysfunction can present either as paralysis or hyperkinesis (hyperkinesia). Conservative and surgical treatment options aimed at restoring normal motor function and correcting the movement disorders are described. Static reanimation techniques are not dealt with. The final section describes the use of botulinum toxin in the therapy of dysphagia. PMID:22073058

  5. Functional Interplay of Two Paralogs Encoding SWI/SNF Chromatin-Remodeling Accessory Subunits During Caenorhabditis elegans Development.

    PubMed

    Ertl, Iris; Porta-de-la-Riva, Montserrat; Gómez-Orte, Eva; Rubio-Peña, Karinna; Aristizábal-Corrales, David; Cornes, Eric; Fontrodona, Laura; Osteikoetxea, Xabier; Ayuso, Cristina; Askjaer, Peter; Cabello, Juan; Cerón, Julián

    2016-03-01

    SWI/SNF ATP-dependent chromatin-remodeling complexes have been related to several cellular processes such as transcription, regulation of chromosomal stability, and DNA repair. The Caenorhabditis elegans gene ham-3 (also known as swsn-2.1) and its paralog swsn-2.2 encode accessory subunits of SWI/SNF complexes. Using RNA interference (RNAi) assays and diverse alleles we investigated whether ham-3 and swsn-2.2 have different functions during C. elegans development since they encode proteins that are probably mutually exclusive in a given SWI/SNF complex. We found that ham-3 and swsn-2.2 display similar functions in vulva specification, germline development, and intestinal cell proliferation, but have distinct roles in embryonic development. Accordingly, we detected functional redundancy in some developmental processes and demonstrated by RNA sequencing of RNAi-treated L4 animals that ham-3 and swsn-2.2 regulate the expression of a common subset of genes but also have specific targets. Cell lineage analyses in the embryo revealed hyper-proliferation of intestinal cells in ham-3 null mutants whereas swsn-2.2 is required for proper cell divisions. Using a proteomic approach, we identified SWSN-2.2-interacting proteins needed for early cell divisions, such as SAO-1 and ATX-2, and also nuclear envelope proteins such as MEL-28. swsn-2.2 mutants phenocopy mel-28 loss-of-function, and we observed that SWSN-2.2 and MEL-28 colocalize in mitotic and meiotic chromosomes. Moreover, we demonstrated that SWSN-2.2 is required for correct chromosome segregation and nuclear reassembly after mitosis including recruitment of MEL-28 to the nuclear periphery.

  6. Functional Interplay of Two Paralogs Encoding SWI/SNF Chromatin-Remodeling Accessory Subunits During Caenorhabditis elegans Development

    PubMed Central

    Ertl, Iris; Porta-de-la-Riva, Montserrat; Gómez-Orte, Eva; Rubio-Peña, Karinna; Aristizábal-Corrales, David; Cornes, Eric; Fontrodona, Laura; Osteikoetxea, Xabier; Ayuso, Cristina; Askjaer, Peter; Cabello, Juan; Cerón, Julián

    2016-01-01

    SWI/SNF ATP-dependent chromatin-remodeling complexes have been related to several cellular processes such as transcription, regulation of chromosomal stability, and DNA repair. The Caenorhabditis elegans gene ham-3 (also known as swsn-2.1) and its paralog swsn-2.2 encode accessory subunits of SWI/SNF complexes. Using RNA interference (RNAi) assays and diverse alleles we investigated whether ham-3 and swsn-2.2 have different functions during C. elegans development since they encode proteins that are probably mutually exclusive in a given SWI/SNF complex. We found that ham-3 and swsn-2.2 display similar functions in vulva specification, germline development, and intestinal cell proliferation, but have distinct roles in embryonic development. Accordingly, we detected functional redundancy in some developmental processes and demonstrated by RNA sequencing of RNAi-treated L4 animals that ham-3 and swsn-2.2 regulate the expression of a common subset of genes but also have specific targets. Cell lineage analyses in the embryo revealed hyper-proliferation of intestinal cells in ham-3 null mutants whereas swsn-2.2 is required for proper cell divisions. Using a proteomic approach, we identified SWSN-2.2-interacting proteins needed for early cell divisions, such as SAO-1 and ATX-2, and also nuclear envelope proteins such as MEL-28. swsn-2.2 mutants phenocopy mel-28 loss-of-function, and we observed that SWSN-2.2 and MEL-28 colocalize in mitotic and meiotic chromosomes. Moreover, we demonstrated that SWSN-2.2 is required for correct chromosome segregation and nuclear reassembly after mitosis including recruitment of MEL-28 to the nuclear periphery. PMID:26739451

  7. Assessment of differential item functioning.

    PubMed

    Wang, Wen-Chung

    2008-01-01

    This study addresses several important issues in assessment of differential item functioning (DIF). It starts with the definition of DIF, effectiveness of using item fit statistics to detect DIF, and linear modeling of DIF in dichotomous items, polytomous items, facets, and testlet-based items. Because a common metric over groups of test-takers is a prerequisite in DIF assessment, this study reviews three such methods of establishing a common metric: the equal-mean-difficulty method, the all-other-item method, and the constant-item (CI) method. A small simulation demonstrates the superiority of the CI method over the others. As the CI method relies on a correct specification of DIF-free items to serve as anchors, a method of identifying such items is recommended and its effectiveness is illustrated through a simulation. Finally, this study discusses how to assess practical significance of DIF at both item and test levels.

  8. Functional Analysis of the Accessory Protein TapA in Bacillus subtilis Amyloid Fiber Assembly

    PubMed Central

    Romero, Diego; Vlamakis, Hera; Losick, Richard

    2014-01-01

    Bacillus subtilis biofilm formation relies on the assembly of a fibrous scaffold formed by the protein TasA. TasA polymerizes into highly stable fibers with biochemical and morphological features of functional amyloids. Previously, we showed that assembly of TasA fibers requires the auxiliary protein TapA. In this study, we investigated the roles of TapA sequences from the C-terminal and N-terminal ends and TapA cysteine residues in its ability to promote the assembly of TasA amyloid-like fibers. We found that the cysteine residues are not essential for the formation of TasA fibers, as their replacement by alanine residues resulted in only minor defects in biofilm formation. Mutating sequences in the C-terminal half had no effect on biofilm formation. However, we identified a sequence of 8 amino acids in the N terminus that is key for TasA fiber formation. Strains expressing TapA lacking these 8 residues were completely defective in biofilm formation. In addition, this TapA mutant protein exhibited a dominant negative effect on TasA fiber formation. Even in the presence of wild-type TapA, the mutant protein inhibited fiber assembly in vitro and delayed biofilm formation in vivo. We propose that this 8-residue sequence is crucial for the formation of amyloid-like fibers on the cell surface, perhaps by mediating the interaction between TapA or TapA and TasA molecules. PMID:24488317

  9. Differential Item Functioning from a Multilevel Perspective.

    ERIC Educational Resources Information Center

    van den Bergh, Huub; And Others

    The term differential item functioning (DIF) refers to whether or not the same psychological constructs are measured across different groups. If an item does not measure the same skills or subskills in different populations, it is said to function differentially or to display item bias. A multilevel approach to DIF is proposed. In such a model,…

  10. Sexual Behavior Increases Cell Proliferation in the Rostral Migratory Stream and Promotes the Differentiation of the New Cells into Neurons in the Accessory Olfactory Bulb of Female Rats

    PubMed Central

    Corona, Rebeca; Retana-Márquez, Socorro; Portillo, Wendy; Paredes, Raúl G.

    2016-01-01

    We have previously demonstrated, that 15 days after female rats pace the sexual interaction, there is an increase in the number of new cells that reach the granular cell layer (GrL) of the accessory olfactory bulb (AOB). The aim of the present study was to evaluate, if the first sexual experience in the female rat increases cell proliferation in the subventricular zone (SVZ) and the rostral migratory stream (RMS). We also tested if this behavior promotes the survival of the new cells that integrate into the main olfactory bulb (MOB) and AOB 45 days after the behavioral test. Sexually, naive female rats were injected with the DNA synthesis marker 5′-bromo-2′-deoxyuridine (BrdU) on the day of the behavioral test. They were randomly divided into the following groups: Female rats placed alone in the mating cage (1); Females exposed to amyl acetate odor [banana scent, (2)]; Females that could see, hear, and smell the male but physical contact was not possible [exposed to male, (3)]; Female rats that could pace the sexual interaction (4); and females that mated without the possibility of pacing the sexual interaction (5). Animals were sacrificed 2 days after the behavioral test (proliferation) or 45 days later (survival). Our results show that 2 days after females were exposed to banana scent or to the male, they had a higher number of cells in the SVZ. Females, that mated in pace and no-paced conditions had more new cells in the RMS. At 45 days, no significant differences were found in the number of new cells that survived in the MOB or in the AOB. However, mating increased the percentage of new cells, that differentiated into neurons in the GrL of the AOB. These new cells expressed c-Fos after a second sexual encounter just before the females were sacrificed. No significant differences in plasma levels of estradiol and progesterone were observed between groups. Our results indicate that the first sexual experience increases cell proliferation in the RMS and mating

  11. A novel function for the Hox gene Abd-B in the male accessory gland regulates the long-term female post-mating response in Drosophila.

    PubMed

    Gligorov, Dragan; Sitnik, Jessica L; Maeda, Robert K; Wolfner, Mariana F; Karch, François

    2013-03-01

    In insects, products of the male reproductive tract are essential for initiating and maintaining the female post-mating response (PMR). The PMR includes changes in egg laying, receptivity to courting males, and sperm storage. In Drosophila, previous studies have determined that the main cells of the male accessory gland produce some of the products required for these processes. However, nothing was known about the contribution of the gland's other secretory cell type, the secondary cells. In the course of investigating the late functions of the homeotic gene, Abdominal-B (Abd-B), we discovered that Abd-B is specifically expressed in the secondary cells of the Drosophila male accessory gland. Using an Abd-B BAC reporter coupled with a collection of genetic deletions, we discovered an enhancer from the iab-6 regulatory domain that is responsible for Abd-B expression in these cells and that apparently works independently from the segmentally regulated chromatin domains of the bithorax complex. Removal of this enhancer results in visible morphological defects in the secondary cells. We determined that mates of iab-6 mutant males show defects in long-term egg laying and suppression of receptivity, and that products of the secondary cells are influential during sperm competition. Many of these phenotypes seem to be caused by a defect in the storage and gradual release of sex peptide in female mates of iab-6 mutant males. We also found that Abd-B expression in the secondary cells contributes to glycosylation of at least three accessory gland proteins: ovulin (Acp26Aa), CG1656, and CG1652. Our results demonstrate that long-term post-mating changes observed in mated females are not solely induced by main cell secretions, as previously believed, but that secondary cells also play an important role in male fertility by extending the female PMR. Overall, these discoveries provide new insights into how these two cell types cooperate to produce and maintain a robust female PMR.

  12. Accessory mental foramen

    PubMed Central

    Balcioglu, Huseyin Avni; Kocaelli, Humeyra

    2009-01-01

    Context: Accessory mental foramen is a rare anatomical variation. Even so, in order to avoid neurovascular complications, particular attention should be paid to the possible occurrence of one or more accessory mental foramen during surgical procedures involving the mandible. Case report: A 3-dimensional computed tomography (3D-CT) scan of a female patient revealed an accessory mental foramen on the right side of her mandible. Conclusion: A 3D-CT scan should be obtained prior to mandibular surgeries so that the presence of accessory mental foramen can be detected, and so that the occurrence of a neurosensory disturbance or hemorrhage can be avoided. Although this anatomical variation is rare, it should be kept in mind that an accessory mental foramen may exist. PMID:22666714

  13. Screening Test Items for Differential Item Functioning

    ERIC Educational Resources Information Center

    Longford, Nicholas T.

    2014-01-01

    A method for medical screening is adapted to differential item functioning (DIF). Its essential elements are explicit declarations of the level of DIF that is acceptable and of the loss function that quantifies the consequences of the two kinds of inappropriate classification of an item. Instead of a single level and a single function, sets of…

  14. A class of neutral functional differential equations.

    NASA Technical Reports Server (NTRS)

    Melvin, W. R.

    1972-01-01

    Formulation and study of the initial value problem for neutral functional differential equations. The existence, uniqueness, and continuation of solutions to this problem are investigated, and an analysis is made of the dependence of the solutions on the initial conditions and parameters, resulting in the derivation of a continuous dependence theorem in which the fundamental mathematical principles underlying the continuous dependence problem for a very general system of nonlinear neutral functional differential equations are separated out.

  15. Lipopolysaccharide (LPS)-binding protein and soluble CD14 function as accessory molecules for LPS-induced changes in endothelial barrier function, in vitro.

    PubMed Central

    Goldblum, S E; Brann, T W; Ding, X; Pugin, J; Tobias, P S

    1994-01-01

    Bacterial LPS induces endothelial cell (EC) injury both in vivo and in vitro. We studied the effect of Escherichia coli 0111:B4 LPS on movement of 14C-BSA across bovine pulmonary artery EC monolayers. In the presence of serum, a 6-h LPS exposure augmented (P < 0.001) transendothelial 14C-BSA flux compared with the media control at concentrations > or = 0.5 ng/ml, and LPS (10 ng/ml) exposures of > or = 2-h increased (P < 0.005) the flux. In the absence of serum, LPS concentrations of up to 10 micrograms/ml failed to increase 14C-BSA flux at 6 h. The addition of 10% serum increased EC sensitivity to the LPS stimulus by > 10,000-fold. LPS (10 ng/ml, 6 h) failed to increase 14C-BSA flux at serum concentrations < 0.5%, and maximum LPS-induced increments could be generated in the presence of > or = 2.5%. LPS-binding protein (LBP) and soluble CD14 (sCD14) could each satisfy this serum requirement; either anti-LBP or anti-CD14 antibody each totally blocked (P < 0.00005) the LPS-induced changes in endothelial barrier function. LPS-LBP had a more rapid onset than did LPS-sCD14. The LPS effect in the presence of both LBP and sCD14 exceeded the effect in the presence of either protein alone. These data suggest that LBP and sCD14 each independently functions as an accessory molecule for LPS presentation to the non-CD14-bearing endothelial surface. However, in the presence of serum both molecules are required. Images PMID:7509346

  16. Accessory Breast Carcinoma

    PubMed Central

    Youn, Hyun Jo; Jung, Sung Hoo

    2009-01-01

    Summary Background Ectopic breast tissue usually develops along the mammary ridges, and the incidence has been reported to be 2–6% of the general population. Occurrence of primary carcinoma in ectopic breast tissue is rare. Case Report We report the case of 59-year-old woman with accessory breast carcinoma in her left axilla. Conclusion Because an accessory areola or nipple is often missing and awareness of physicians and patients about these unsuspicious masses is lacking, clinical diagnosis of accessory breast carcinoma is frequently delayed. Therefore, a mass along the ‘milk line’ should be examined carefully, and any suspicious lesions should be evaluated. PMID:20847887

  17. Function of caspase-14 in trophoblast differentiation

    PubMed Central

    White, Lloyd J; Declercq, Wim; Arfuso, Frank; Charles, Adrian K; Dharmarajan, Arun M

    2009-01-01

    Background Within the human placenta, the cytotrophoblast consists of a proliferative pool of progenitor cells which differentiate to replenish the overlying continuous, multi-nucleated syncytiotrophoblast, which forms the barrier between the maternal and fetal tissues. Disruption to trophoblast differentiation and function may result in impaired fetal development and preeclampsia. Caspase-14 expression is limited to barrier forming tissues. It promotes keratinocyte differentiation by cleaving profilaggrin to stabilise keratin intermediate filaments, and indirectly providing hydration and UV protection. However its role in the trophoblast remains unexplored. Methods Using RNA Interference the reaction of control and differentiating trophoblastic BeWo cells to suppressed caspase-14 was examined for genes pertaining to hormonal, cell cycle and cytoskeletal pathways. Results Transcription of hCG, KLF4 and cytokeratin-18 were increased following caspase-14 suppression suggesting a role for caspase-14 in inhibiting their pathways. Furthermore, hCG, KLF4 and cytokeratin-18 protein levels were disrupted. Conclusion Since expression of these molecules is normally increased with trophoblast differentiation, our results imply that caspase-14 inhibits trophoblast differentiation. This is the first functional study of this unusual member of the caspase family in the trophoblast, where it has a different function than in the epidermis. This knowledge of the molecular underpinnings of trophoblast differentiation may instruct future therapies of trophoblast disease. PMID:19747408

  18. The Accessory Genome of Pseudomonas aeruginosa

    PubMed Central

    Kung, Vanderlene L.; Ozer, Egon A.; Hauser, Alan R.

    2010-01-01

    Summary: Pseudomonas aeruginosa strains exhibit significant variability in pathogenicity and ecological flexibility. Such interstrain differences reflect the dynamic nature of the P. aeruginosa genome, which is composed of a relatively invariable “core genome” and a highly variable “accessory genome.” Here we review the major classes of genetic elements comprising the P. aeruginosa accessory genome and highlight emerging themes in the acquisition and functional importance of these elements. Although the precise phenotypes endowed by the majority of the P. aeruginosa accessory genome have yet to be determined, rapid progress is being made, and a clearer understanding of the role of the P. aeruginosa accessory genome in ecology and infection is emerging. PMID:21119020

  19. Membrane Ia expression and antigen-presenting accessory cell function of L cells transfected with class II major histocompatibility complex genes

    PubMed Central

    1984-01-01

    To study the relationship between the structure and function of Ia antigens, as well as the physiologic requirements for antigen presentation to major histocompatibility complex-restricted T cells, class II A alpha and A beta genes from the k and d haplotypes were transfected into Ltk- fibroblasts using the calcium phosphate coprecipitation technique. Individually transfected genes were actively transcribed in the L cells without covalent linkage to, or cotransformation with, viral enhancer sequences. However, cell surface expression of detectable I-A required the presence of transfected A alpha dA beta d or A alpha kA beta k pairs in a single cell. The level of I-A expression under these conditions was 1/5-1/10 that of Ia+ B lymphoma cells, or B lymphoma cells expressing transfected class II genes. These I-A-expressing transfectants were tested for accessory cell function and shown to present polypeptide and complex protein antigens to T cell clones and hybridomas in the context of the transfected gene products. One T cell clone, restricted to I-Ak plus GAT (L-glutamic acid60-L-alanine30-L-tyrosine10), had a profound cytotoxic effect on I-Ak- but not I-Ad-expressing transfectants in the presence of specific antigen. Assays of unprimed T cells showed that both Ia+ and Ia- L cells could serve as accessory cells for concanavalin A-induced proliferative responses. These data indicate that L cells can transcribe, translate, and express transfected class II genes and that such I-A-bearing L cells possess the necessary metabolic mechanisms for presenting these antigens to T lymphocytes in the context of their I-A molecules. PMID:6436430

  20. Examining the Relationship between Differential Item Functioning and Differential Test Functioning

    ERIC Educational Resources Information Center

    Pae, Tae-Il; Park, Gi-Pyo

    2006-01-01

    The present study utilized both the IRT-LR (item response theory likelihood ratio) and a series of CFA (confirmatory factor analysis) multi-sample analyses to systematically examine the relationships between DIF (differential item functioning) and DTF (differential test functioning) with a random sample of 15 000 Korean examinees. Specifically,…

  1. Estimating the Importance of Differential Item Functioning.

    ERIC Educational Resources Information Center

    Rudas, Tamas; Zwick, Rebecca

    1997-01-01

    The mixture index of fit (T. Rudas et al, 1994) is used to estimate the fraction of a population for which differential item functioning (DIF) occurs, and this approach is compared to the Mantel Haenszel test of DIF. The proposed noniterative procedure provides information about data portions contributing to DIF. (SLD)

  2. A Multilevel Assessment of Differential Item Functioning.

    ERIC Educational Resources Information Center

    Shen, Linjun

    A multilevel approach was proposed for the assessment of differential item functioning and compared with the traditional logistic regression approach. Data from the Comprehensive Osteopathic Medical Licensing Examination for 2,300 freshman osteopathic medical students were analyzed. The multilevel approach used three-level hierarchical generalized…

  3. Ramsay-Curve Differential Item Functioning

    ERIC Educational Resources Information Center

    Woods, Carol M.

    2011-01-01

    Differential item functioning (DIF) occurs when an item on a test, questionnaire, or interview has different measurement properties for one group of people versus another, irrespective of true group-mean differences on the constructs being measured. This article is focused on item response theory based likelihood ratio testing for DIF (IRT-LR or…

  4. Real and Artificial Differential Item Functioning

    ERIC Educational Resources Information Center

    Andrich, David; Hagquist, Curt

    2012-01-01

    The literature in modern test theory on procedures for identifying items with differential item functioning (DIF) among two groups of persons includes the Mantel-Haenszel (MH) procedure. Generally, it is not recognized explicitly that if there is real DIF in some items which favor one group, then as an artifact of this procedure, artificial DIF…

  5. Differential Item Functioning Analysis Using Rasch Item Information Functions

    ERIC Educational Resources Information Center

    Wyse, Adam E.; Mapuranga, Raymond

    2009-01-01

    Differential item functioning (DIF) analysis is a statistical technique used for ensuring the equity and fairness of educational assessments. This study formulates a new DIF analysis method using the information similarity index (ISI). ISI compares item information functions when data fits the Rasch model. Through simulations and an international…

  6. IL1-receptor accessory protein-like 1 (IL1RAPL1), a protein involved in cognitive functions, regulates N-type Ca2+-channel and neurite elongation.

    PubMed

    Gambino, Frédéric; Pavlowsky, Alice; Béglé, Aurélie; Dupont, Jean-Luc; Bahi, Nadia; Courjaret, Raphael; Gardette, Robert; Hadjkacem, Hassen; Skala, Henriette; Poulain, Bernard; Chelly, Jamel; Vitale, Nicolas; Humeau, Yann

    2007-05-22

    Null mutations in the IL1-receptor accessory protein-like 1 gene (IL1RAPL1) are responsible for an inherited X-linked form of cognitive impairment. IL1RAPL1 protein physically interacts with neuronal calcium sensor-1 (NCS-1), but the functional impact of the IL1RAPL1/NCS-1 interaction remains unknown. Here, we demonstrate that stable expression of IL1RAPL1 in PC12 cells induces a specific silencing of N-type voltage-gated calcium channels (N-VGCC) activity that explains a secretion deficit observed in these IL1RAPL1 cells. Importantly, this modulation of VGCC activity is mediated by NCS-1. Indeed, a specific loss-of-function of N-VGCC was observed in PC12 cells overexpressing NCS-1, and a total recovery of N-VGCC activity was obtained by a down-regulation of NCS-1 in IL1RAPL1 cells. The functional relevance of the interaction between IL1RAPL1 and NCS-1 was also suggested by the reduction of neurite elongation observed in nerve growth factor (NGF)-treated IL1RAPL1 cells, a phenotype rescued by NCS-1 inactivation. Because both proteins are highly expressed in neurons, these results suggest that IL1RAPL1-related mental retardation could result from a disruption of N-VGCC and/or NCS-1-dependent synaptic and neuronal activities.

  7. Differential pleiotropy and HOX functional organization.

    PubMed

    Sivanantharajah, Lovesha; Percival-Smith, Anthony

    2015-02-01

    Key studies led to the idea that transcription factors are composed of defined modular protein motifs or domains, each with separable, unique function. During evolution, the recombination of these modular domains could give rise to transcription factors with new properties, as has been shown using recombinant molecules. This archetypic, modular view of transcription factor organization is based on the analyses of a few transcription factors such as GAL4, which may represent extreme exemplars rather than an archetype or the norm. Recent work with a set of Homeotic selector (HOX) proteins has revealed differential pleiotropy: the observation that highly-conserved HOX protein motifs and domains make small, additive, tissue specific contributions to HOX activity. Many of these differentially pleiotropic HOX motifs may represent plastic sequence elements called short linear motifs (SLiMs). The coupling of differential pleiotropy with SLiMs, suggests that protein sequence changes in HOX transcription factors may have had a greater impact on morphological diversity during evolution than previously believed. Furthermore, differential pleiotropy may be the genetic consequence of an ensemble nature of HOX transcription factor allostery, where HOX proteins exist as an ensemble of states with the capacity to integrate an extensive array of developmental information. Given a new structural model for HOX functional domain organization, the properties of the archetypic TF may require reassessment.

  8. Synchronization with propagation - The functional differential equations

    NASA Astrophysics Data System (ADS)

    Rǎsvan, Vladimir

    2016-06-01

    The structure represented by one or several oscillators couple to a one-dimensional transmission environment (e.g. a vibrating string in the mechanical case or a lossless transmission line in the electrical case) turned to be attractive for the research in the field of complex structures and/or complex behavior. This is due to the fact that such a structure represents some generalization of various interconnection modes with lumped parameters for the oscillators. On the other hand the lossless and distortionless propagation along transmission lines has generated several research in electrical, thermal, hydro and control engineering leading to the association of some functional differential equations to the basic initial boundary value problems. The present research is performed at the crossroad of the aforementioned directions. We shall associate to the starting models some functional differential equations - in most cases of neutral type - and make use of the general theorems for existence and stability of forced oscillations for functional differential equations. The challenges introduced by the analyzed problems for the general theory are emphasized, together with the implication of the results for various applications.

  9. Diverse amino acid residues function within the type 1 peroxisomal targeting signal. Implications for the role of accessory residues upstream of the type 1 peroxisomal targeting signal.

    PubMed

    Mullen, R T; Lee, M S; Flynn, C R; Trelease, R N

    1997-11-01

    The purpose of this study was to determine whether the plant type 1 peroxisomal targeting signal (PTS1) utilizes amino acid residues that do not strictly adhere to the serine-lysine-leucine (SKL) motif (small-basic-hydrophobic residues). Selected residues were appended to the C terminus of chloramphenicol acetyltransferase (CAT) and were tested for their ability to target CAT fusion proteins to glyoxysomes in tobacco (Nicotiana tabacum L.) cv Bright Yellow 2 suspension-cultured cells. CAT was redirected from the cytosol into glyoxysomes by a wide range of residues, i.e. A/C/G/S/T-H/K/ L/N/R-I/L/M/Y. Although L and N at the -2 position (-SLL, -ANL) do not conform to the SKL motif, both functioned, but in a temporally less-efficient manner. Other SKL divergent residues, however, did not target CAT to glyoxysomes, i.e. F or P at the -3 position (-FKL, -PKL), S or T at the -2 position (-SSI, STL), or D at the -1 position (-SKD). The targeting inefficiency of CAT-ANL could be ameliorated when K was included at the -4 position (-KANL). In summary, the plant PTS1 mostly conforms to the SKL motif. For those PTS1s that possess nonconforming residue(s), other residues upstream of the PTS1 appear to function as accessory sequences that enhance the temporal efficiency of peroxisomal targeting.

  10. 26 CFR 48.4061(b)-2 - Definition of parts or accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... automotive speedometers; as well as replacement parts for automobile engines, transmissions, differentials, steering mechanisms, timers, windshild-wiper motors, and other automobile parts or accessories....

  11. 26 CFR 48.4061(b)-2 - Definition of parts or accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... automotive speedometers; as well as replacement parts for automobile engines, transmissions, differentials, steering mechanisms, timers, windshild-wiper motors, and other automobile parts or accessories....

  12. 26 CFR 48.4061(b)-2 - Definition of parts or accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... automotive speedometers; as well as replacement parts for automobile engines, transmissions, differentials, steering mechanisms, timers, windshild-wiper motors, and other automobile parts or accessories....

  13. Visual determination of differential renal function

    SciTech Connect

    Kipper, M.S.; Witztum, K.F.; Taylor, A. Jr.

    1986-05-01

    Forty patients (43 studies) referred for determination of differential renal function were imaged 24 hours after intravenous administration of Tc-99m-2, 3 DMSA. Visual assessment of relative renal uptake was estimated independently by three observers at three different hospitals from analog images on standard x-ray film. The results were compared with the relative DMSA uptake obtained by summing counts in computer-assisted regions of interest placed over each kidney. There was excellent correlation between the visual estimates of each observer and the computer-generated values (r = 0.98, 0.96, and 0.98, respectively). If a computer is not available, good visual estimates of differential uptake still may be obtained when static imaging agents such as DMSA are administered.

  14. Effects of Small Molecule Calcium-Activated Chloride Channel Inhibitors on Structure and Function of Accessory Cholera Enterotoxin (Ace) of Vibrio cholerae

    PubMed Central

    Chatterjee, Tanaya; Sheikh, Irshad Ali; Chakravarty, Devlina; Chakrabarti, Pinak; Sarkar, Paramita; Saha, Tultul; Chakrabarti, Manoj K.; Hoque, Kazi Mirajul

    2015-01-01

    Cholera pathogenesis occurs due to synergistic pro-secretory effects of several toxins, such as cholera toxin (CTX) and Accessory cholera enterotoxin (Ace) secreted by Vibrio cholerae strains. Ace activates chloride channels stimulating chloride/bicarbonate transport that augments fluid secretion resulting in diarrhea. These channels have been targeted for drug development. However, lesser attention has been paid to the interaction of chloride channel modulators with bacterial toxins. Here we report the modulation of the structure/function of recombinant Ace by small molecule calcium-activated chloride channel (CaCC) inhibitors, namely CaCCinh-A01, digallic acid (DGA) and tannic acid. Biophysical studies indicate that the unfolding (induced by urea) free energy increases upon binding CaCCinh-A01 and DGA, compared to native Ace, whereas binding of tannic acid destabilizes the protein. Far-UV CD experiments revealed that the α-helical content of Ace-CaCCinh-A01 and Ace-DGA complexes increased relative to Ace. In contrast, binding to tannic acid had the opposite effect, indicating the loss of protein secondary structure. The modulation of Ace structure induced by CaCC inhibitors was also analyzed using docking and molecular dynamics (MD) simulation. Functional studies, performed using mouse ileal loops and Ussing chamber experiments, corroborate biophysical data, all pointing to the fact that tannic acid destabilizes Ace, inhibiting its function, whereas DGA stabilizes the toxin with enhanced fluid accumulation in mouse ileal loop. The efficacy of tannic acid in mouse model suggests that the targeted modulation of Ace structure may be of therapeutic benefit for gastrointestinal disorders. PMID:26540279

  15. Effects of Small Molecule Calcium-Activated Chloride Channel Inhibitors on Structure and Function of Accessory Cholera Enterotoxin (Ace) of Vibrio cholerae.

    PubMed

    Chatterjee, Tanaya; Sheikh, Irshad Ali; Chakravarty, Devlina; Chakrabarti, Pinak; Sarkar, Paramita; Saha, Tultul; Chakrabarti, Manoj K; Hoque, Kazi Mirajul

    2015-01-01

    Cholera pathogenesis occurs due to synergistic pro-secretory effects of several toxins, such as cholera toxin (CTX) and Accessory cholera enterotoxin (Ace) secreted by Vibrio cholerae strains. Ace activates chloride channels stimulating chloride/bicarbonate transport that augments fluid secretion resulting in diarrhea. These channels have been targeted for drug development. However, lesser attention has been paid to the interaction of chloride channel modulators with bacterial toxins. Here we report the modulation of the structure/function of recombinant Ace by small molecule calcium-activated chloride channel (CaCC) inhibitors, namely CaCCinh-A01, digallic acid (DGA) and tannic acid. Biophysical studies indicate that the unfolding (induced by urea) free energy increases upon binding CaCCinh-A01 and DGA, compared to native Ace, whereas binding of tannic acid destabilizes the protein. Far-UV CD experiments revealed that the α-helical content of Ace-CaCCinh-A01 and Ace-DGA complexes increased relative to Ace. In contrast, binding to tannic acid had the opposite effect, indicating the loss of protein secondary structure. The modulation of Ace structure induced by CaCC inhibitors was also analyzed using docking and molecular dynamics (MD) simulation. Functional studies, performed using mouse ileal loops and Ussing chamber experiments, corroborate biophysical data, all pointing to the fact that tannic acid destabilizes Ace, inhibiting its function, whereas DGA stabilizes the toxin with enhanced fluid accumulation in mouse ileal loop. The efficacy of tannic acid in mouse model suggests that the targeted modulation of Ace structure may be of therapeutic benefit for gastrointestinal disorders.

  16. Phylogenetic Insights into the Functional Relationship between Primate Lentiviral Reverse Transcriptase and Accessory Proteins Vpx/Vpr

    PubMed Central

    Sakai, Yosuke; Doi, Naoya; Miyazaki, Yasuyuki; Adachi, Akio; Nomaguchi, Masako

    2016-01-01

    The efficiency of reverse transcription to synthesize viral DNA in infected cells greatly influences replication kinetics of retroviruses. However, viral replication in non-dividing cells such as resting T cells and terminally differentiated macrophages is potently and kinetically restricted by a host antiviral factor designated SAMHD1 (sterile alpha motif and HD-domain containing protein 1). SAMHD1 reduces cellular deoxynucleoside triphosphate (dNTP) pools and affects viral reverse transcription step. Human immunodeficiency virus type 2 (HIV-2) and some simian immunodeficiency viruses (SIVs) have Vpx or Vpr to efficiently degrade SAMHD1. Interestingly, the reverse transcriptase (RT) derived from HIV-1 that encodes no anti-SAMHD1 proteins has been previously demonstrated to uniquely exhibit a high enzymatic activity. It is thus not irrational to assume that some viruses may have acquired or lost the specific RT property to better adapt themselves to the low dNTP environments confronted in non-dividing cells. This adaptation process may probably be correlated with the SAMHD1-antagonizing ability by viruses. In this report, we asked whether such adaptive events can be inferable from Vpx/Vpr and RT phylogenetic trees overlaid with SAMHD1-degrading capacity of Vpx/Vpr and with kinetic characteristics of RT. Resultant two trees showed substantially similar clustering patterns, and therefore suggested that the properties of RT and Vpx/Vpr can be linked. In other words, HIV/SIVs may possess their own RT proteins to adequately react to various dNTP circumstances in target cells. PMID:27803699

  17. Asplund sets, differentiability and subdifferentiability of functions in Banach spaces

    NASA Astrophysics Data System (ADS)

    Wang, Xianfu

    2006-11-01

    We show that Asplund sets are effective tools to study differentiability of Lipschitz functions, and [epsilon]-subdifferentiability of lower semicontinuous functions on general Banach spaces. If a locally Lipschitz function defined on an Asplund generated space has a minimal Clarke subdifferential mapping, then it is -uniformly strictly differentiable on a dense G[delta] subset of X. Examples are given of locally Lipschitz functions that are -uniformly strictly differentiable everywhere, but nowhere Frechet differentiable.

  18. Extracranial spinal accessory nerve injury.

    PubMed

    Donner, T R; Kline, D G

    1993-06-01

    Eighty-three consecutive patients with extracranial accessory nerve injury seen over a 12-year period are reviewed. The most common etiology was iatrogenic injury to the nerve at the time of previous surgery. Such operations were usually minor in nature and often related to lymph node or benign tumor removal. Examination usually distinguished winging due to trapezius weakness from that of serratus anterior palsy. Trapezius weakness was seen in all cases. Sternocleidomastoid weakness was unusual. Patients with accessory palsy were evaluated by both clinical and electromyographic studies. Patients who exhibited no clinical or electrical evidence of regeneration were operated on (44 cases). Based on intraoperative nerve action potential studies, 8 lesions in continuity had neurolysis alone. Resection with repair either by end-to-end suture or by grafts was necessary in 31 cases. One case had suture removed from nerve, two had nerve placed into target muscle, and two had more proximal neurotization. Function was usually improved in both operative and nonoperative patients. Related anatomy is discussed.

  19. Stability and control of functional differential equations

    NASA Astrophysics Data System (ADS)

    Peet, Matthew Monnig

    This thesis addresses the question of stability of systems defined by differential equations which contain nonlinearity and delay. In particular, we analyze the stability of a well-known delayed nonlinear implementation of a certain Internet congestion control protocol. We also describe a generalized methodology for proving stability of time-delay systems through the use of semidefinite programming. In Chapters 4 and 5, we consider an Internet congestion control protocol based on the decentralized gradient projection algorithm. For a certain class of utility function, this algorithm was shown to be globally convergent for some sufficiently small value of a gain parameter. Later work gave an explicit bound on this gain for a linearized version of the system. This thesis proves that this bound also implies stability of the original system. The proof is constructed within a generalized passivity framework. The dynamics of the system are separated into a linear, delayed component and a system defined by a nonlinear differential equation with discontinuity in the dynamics. Frequency-domain analysis is performed on the linear component and time-domain analysis is performed on the nonlinear discontinuous system. In Chapter 7, we describe a general methodology for proving stability of linear time-delay systems by computing solutions to an operator-theoretic version of the Lyapunov inequality via semidefinite programming. The result is stated in terms of a nested sequence of sufficient conditions which are of increasing accuracy. This approach is generalized to the case of parametric uncertainty by considering parameter-dependent Lyapunov functionals. Numerical examples are given to demonstrate convergence of the algorithm. In Chapter 8, this approach is generalized to nonlinear time-delay systems through the use of non-quadratic Lyapunov functionals.

  20. Distinguishing Differential Testlet Functioning from Differential Bundle Functioning Using the Multilevel Measurement Model

    ERIC Educational Resources Information Center

    Beretvas, S. Natasha; Walker, Cindy M.

    2012-01-01

    This study extends the multilevel measurement model to handle testlet-based dependencies. A flexible two-level testlet response model (the MMMT-2 model) for dichotomous items is introduced that permits assessment of differential testlet functioning (DTLF). A distinction is made between this study's conceptualization of DTLF and that of…

  1. Multiple-Group Noncompensatory Differential Item Functioning in Raju's Differential Functioning of Items and Tests

    ERIC Educational Resources Information Center

    Oshima, T. C.; Wright, Keith; White, Nick

    2015-01-01

    Raju, van der Linden, and Fleer (1995) introduced a framework for differential functioning of items and tests (DFIT) for unidimensional dichotomous models. Since then, DFIT has been shown to be a quite versatile framework as it can handle polytomous as well as multidimensional models both at the item and test levels. However, DFIT is still limited…

  2. Human monocyte-derived soluble product(s) has an accessory function in the generation of histamine- and concanavalin A-induced suppressor T cells.

    PubMed

    Beer, D J; Dinarello, C A; Rosenwasser, L J; Rocklin, R E

    1982-08-01

    We have analyzed the cellular interactions required for the generation of histamine- and concanavalin A (Con A)-induced suppressor T cells by employing a co-culture assay and techniques for fractionation of human blood mononuclear cells (PBMC). PBMC cultured in the presence of histamine (0.1 mM-1 mM) or Con A (20 micrograms/ml) for 24 h, mitomycin treated and subsequently combined with autologous mitogen-stimulated mononuclear cells, significantly suppressed a subsequent blastogenic response. PBMC fractionated over nylon wool columns and depleted of adherent cells and enriched for T cells (NWNA-T) were unable to generate suppressor activity. However, suppressor cell function by NWNA-T cells was reconstituted by the addition of autologous monocytes. In both the histamine and ConA suppressor systems, the requirement for monocytes in the activation process was enhanced by suspending the NWNA-T population in supernatants derived from allogeneic monocytes stimulated with heat-killed Staphylococcus albus. These crude supernatants contained leukocytic pyrogen (LP) and lymphocyte activating factor (LAF). Sequential purification and separation of the crude supernatants using gel-filtration, immunoadsorption, and isoelectric focusing demonstrated that only those fractions containing LP and LAF were capable to reconstituting NWNA-T cell histamine and Con A-induced suppressor activity. Thus, these studies suggest that the accessory role of supernatants derived from activated monocytes in the generation of suppressor cells may be mediated by LP/LAF. Further studies are in progress to explore the mechanism by which soluble factors stimulate suppressor T cells.

  3. A new kind of auxiliary heart in insects: functional morphology and neuronal control of the accessory pulsatile organs of the cricket ovipositor

    PubMed Central

    2014-01-01

    Introduction In insects, the pumping of the dorsal heart causes circulation of hemolymph throughout the central body cavity, but not within the interior of long body appendages. Hemolymph exchange in these dead-end structures is accomplished by special flow-guiding structures and/or autonomous pulsatile organs (“auxiliary hearts”). In this paper accessory pulsatile organs for an insect ovipositor are described for the first time. We studied these organs in females of the cricket Acheta domesticus by analyzing their functional morphology, neuroanatomy and physiological control. Results The lumen of the four long ovipositor valves is subdivided by longitudinal septa of connective tissue into efferent and afferent hemolymph sinuses which are confluent distally. The countercurrent flow in these sinuses is effected by pulsatile organs which are located at the bases of the ovipositor valves. Each of the four organs consists of a pumping chamber which is compressed by rhythmically contracting muscles. The morphology of the paired organs is laterally mirrored, and there are differences in some details between the dorsal and ventral organs. The compression of the pumping chambers of each valve pair occurs with a left-right alternating rhythm with a frequency of 0.2 to 0.5 Hz and is synchronized between the dorsal and ventral organs. The more anteriorly located genital chamber shows rhythmical lateral movements simultaneous to those of the ovipositor pulsatile organs and probably supports the hemolymph exchange in the abdominal apex region. The left-right alternating rhythm is produced by a central pattern generator located in the terminal ganglion. It requires no sensory feedback for its output since it persists in the completely isolated ganglion. Rhythm-modulating and rhythm-resetting interneurons are identified in the terminal ganglion. Conclusion The circulatory organs of the cricket ovipositor have a unique functional morphology. The pumping apparatus at the base

  4. Torsion of Accessory Hepatic Lobe

    PubMed Central

    Natarajan, Saravanan; Jayasudha; Periasamy, Manikandhan; Rangasamy, Saminathan

    2017-01-01

    An accessory hepatic lobe is a rare congenital anomaly that can undergo torsion and present as an acute surgical emergency. A 5-year-old child admitted as acute abdomen, on laparotomy found to have torsion of accessory lobe of liver, is being reported. PMID:28082782

  5. The scolopidial accessory organ in the Jerusalem cricket (Orthoptera: Stenopelmatidae).

    PubMed

    Strauß, Johannes

    2017-03-01

    Multiple mechanosensory organs form the subgenual organ complex in orthopteroid insects, located in the proximal tibia. In several Ensifera (Orthoptera), a small chordotonal organ, the so-called accessory organ, is the most posterior part of this sensory complex. In order to document the presence of this accessory organ among the Ensifera, the chordotonal sensilla and their innervation in the posterior tibia of two species of Jerusalem crickets (Stenopelmatidae: Stenopelmatus) is described. The sensory structures were stained by axonal tracing. Scolopidial sensilla occur in the posterior subgenual organ and the accessory organ in all leg pairs. The accessory organ contains 10-17 scolopidial sensilla. Both groups of sensilla are commonly spatially separated. However, in few cases neuronal fibres occurred between both organs. The two sensillum groups are considered as separate organs by the general spatial separation and innervation by different nerve branches. A functional role for mechanoreception is considered: since the accessory organ is located closely under the cuticle, sensilla may be suited to detect vibrations transferred over the leg's surface. This study extends the known taxa with an accessory organ, which occurs in several taxa of Ensifera. Comparative neuroanatomy thus suggests that the accessory organ may be conserved at least in Tettigoniidea.

  6. AcCNET (Accessory Genome Constellation Network): comparative genomics software for accessory genome analysis using bipartite networks.

    PubMed

    Lanza, Val F; Baquero, Fernando; de la Cruz, Fernando; Coque, Teresa M

    2017-01-15

    AcCNET (Accessory genome Constellation Network) is a Perl application that aims to compare accessory genomes of a large number of genomic units, both at qualitative and quantitative levels. Using the proteomes extracted from the analysed genomes, AcCNET creates a bipartite network compatible with standard network analysis platforms. AcCNET allows merging phylogenetic and functional information about the concerned genomes, thus improving the capability of current methods of network analysis. The AcCNET bipartite network opens a new perspective to explore the pangenome of bacterial species, focusing on the accessory genome behind the idiosyncrasy of a particular strain and/or population.

  7. Legendre-Tau approximations for functional differential equations

    NASA Technical Reports Server (NTRS)

    Ito, K.; Teglas, R.

    1983-01-01

    The numerical approximation of solutions to linear functional differential equations are considered using the so called Legendre tau method. The functional differential equation is first reformulated as a partial differential equation with a nonlocal boundary condition involving time differentiation. The approximate solution is then represented as a truncated Legendre series with time varying coefficients which satisfy a certain system of ordinary differential equations. The method is very easy to code and yields very accurate approximations. Convergence is established, various numerical examples are presented, and comparison between the latter and cubic spline approximations is made.

  8. Thermomechanical milling of accessory lithics in volcanic conduits

    NASA Astrophysics Data System (ADS)

    Campbell, Michelle E.; Russell, James K.; Porritt, Lucy A.

    2013-09-01

    Accessory lithic clasts recovered from pyroclastic deposits commonly result from the failure of conduit wall rocks, and represent an underutilized resource for constraining conduit processes during explosive volcanic eruptions. The morphological features of lithic clasts provide distinctive 'textural fingerprints' of processes that have reshaped them during transport in the conduit. Here, we present the first study focused on accessory lithic clast morphology and show how the shapes and surfaces of these accessory pyroclasts can inform on conduit processes. We use two main types of accessory lithic clasts from pyroclastic fallout deposits of the 2360 B.P. subplinian eruption of Mount Meager, British Columbia, as a case study: (i) rough and subangular dacite clasts, and (ii) variably rounded and smoothed monzogranite clasts. The quantitative morphological data collected on these lithics include: mass, volume, density, 2-D image analysis of convexity (C), and 3-D laser scans for sphericity (Ψ) and smoothness (S). Shaping and comminution (i.e. milling) of clasts within the conduit are ascribed to three processes: (1) disruptive fragmentation due to high-energy impacts between clasts or between clasts and conduit walls, (2) ash-blasting of clasts suspended within the volcanic flux, and (3) thermal effects. We use a simplified conduit eruption model to predict ash-blasting velocities and lithic residence times as a function of clast size and source depth, thereby constraining the lithic milling processes. The extent of shape and surface modification (i.e. rounding and honing) is directly proportional to clast residence times within the conduit prior to evacuation. We postulate that the shallow-seated dacite clasts remain subangular and rough due to short (<2 min) residence times, whereas monzogranite clasts are much more rounded and smoothed due to deeper source depths and consequently longer residence times (up to ˜1 h). Larger monzogranite clasts are smoother than

  9. Accessory proteins for heterotrimeric G-proteins in the kidney

    PubMed Central

    Park, Frank

    2015-01-01

    Heterotrimeric G-proteins play a fundamentally important role in regulating signal transduction pathways in the kidney. Accessory proteins are being identified as direct binding partners for heterotrimeric G-protein α or βγ subunits to promote more diverse mechanisms by which G-protein signaling is controlled. In some instances, accessory proteins can modulate the signaling magnitude, localization, and duration following the activation of cell membrane-associated receptors. Alternatively, accessory proteins complexed with their G-protein α or βγ subunits can promote non-canonical models of signaling activity within the cell. In this review, we will highlight the expression profile, localization and functional importance of these newly identified accessory proteins to control the function of select G-protein subunits under normal and various disease conditions observed in the kidney. PMID:26300785

  10. Computations involving differential operators and their actions on functions

    NASA Technical Reports Server (NTRS)

    Crouch, Peter E.; Grossman, Robert; Larson, Richard

    1991-01-01

    The algorithms derived by Grossmann and Larson (1989) are further developed for rewriting expressions involving differential operators. The differential operators involved arise in the local analysis of nonlinear dynamical systems. These algorithms are extended in two different directions: the algorithms are generalized so that they apply to differential operators on groups and the data structures and algorithms are developed to compute symbolically the action of differential operators on functions. Both of these generalizations are needed for applications.

  11. Higher-order automatic differentiation of mathematical functions

    NASA Astrophysics Data System (ADS)

    Charpentier, Isabelle; Dal Cappello, Claude

    2015-04-01

    Functions of mathematical physics such as the Bessel functions, the Chebyshev polynomials, the Gauss hypergeometric function and so forth, have practical applications in many scientific domains. On the one hand, differentiation formulas provided in reference books apply to real or complex variables. These do not account for the chain rule. On the other hand, based on the chain rule, the automatic differentiation has become a natural tool in numerical modeling. Nevertheless automatic differentiation tools do not deal with the numerous mathematical functions. This paper describes formulas and provides codes for the higher-order automatic differentiation of mathematical functions. The first method is based on Faà di Bruno's formula that generalizes the chain rule. The second one makes use of the second order differential equation they satisfy. Both methods are exemplified with the aforementioned functions.

  12. DIF Trees: Using Classification Trees to Detect Differential Item Functioning

    ERIC Educational Resources Information Center

    Vaughn, Brandon K.; Wang, Qiu

    2010-01-01

    A nonparametric tree classification procedure is used to detect differential item functioning for items that are dichotomously scored. Classification trees are shown to be an alternative procedure to detect differential item functioning other than the use of traditional Mantel-Haenszel and logistic regression analysis. A nonparametric…

  13. 14 CFR 33.25 - Accessory attachments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Accessory attachments. 33.25 Section 33.25... STANDARDS: AIRCRAFT ENGINES Design and Construction; General § 33.25 Accessory attachments. The engine must operate properly with the accessory drive and mounting attachments loaded. Each engine accessory drive...

  14. Endoscopic Accessory Navicular Synchondrosis Fusion.

    PubMed

    Lui, Tun Hing

    2016-12-01

    The accessory navicular bone is one of the most common accessory ossicles of the foot. Fewer than 1% of accessory navicular bones are symptomatic, and most of these are type II accessory navicular bones. A separation of the synchondrosis is considered one of the main causes of pain. After an injury to the synchondrosis has resulted in a chondro-osseous disruption, the combined forces of tension and shear from the posterior tibial tendon and the foot aggravate the injury and prevent it from healing. Fusion of the synchondrosis is a logical surgical treatment option if the pain is recalcitrant to conservative measures. The purpose of this technical note is to report an endoscopic approach to achieve fusion. It has the advantages of better cosmesis, less scar pain, less risk of nonunion, and potential to examine the tibialis posterior tendon and the talonavicular joint.

  15. Accessory drive for a turbine engine

    SciTech Connect

    Brogdon, J.W.; Allen, K.D.; Barton, J.S.; Hicks, R.J.

    1987-02-03

    This patent describes, in combination: a radial flow turbine engine having a main shaft and a casing with air inlets open radially at one end, and an accessory drive comprising: an accessory housing positioned axially adjacent the one end of the turbine engine casing, a gear ring rotatably mounted within the accessory housing, means for mechanically drivingly connecting the gear ring to the turbine main shaft, the connecting means comprising a planetary gear arrangement contained in the accessory housing, the accessory housing having apertures open to the gear ring and circumferentially spaced from each other, at least one accessory having a driven gear, and means for mounting the at least one accessory to the accessory housing so that the accessory registers with one of the plurality of apertures and so that the gear ring meshes with the driven gear, wherein each aperture is adapted for connection with a separate accessory.

  16. Net and Global Differential Item Functioning in PISA Polytomously Scored Science Items: Application of the Differential Step Functioning Framework

    ERIC Educational Resources Information Center

    Akour, Mutasem; Sabah, Saed; Hammouri, Hind

    2015-01-01

    The purpose of this study was to apply two types of Differential Item Functioning (DIF), net and global DIF, as well as the framework of Differential Step Functioning (DSF) to real testing data to investigate measurement invariance related to test language. Data from the Program for International Student Assessment (PISA)-2006 polytomously scored…

  17. HIV-1 Accessory Proteins: Vpu and Vif

    PubMed Central

    Andrew, Amy; Strebel, Klaus

    2014-01-01

    HIV-1 Vif and Vpu are accessory factors involved in late stages of viral replication. Vif regulates viral infectivity by preventing virion incorporation of APOBEC3G and other members of the family of cytidine deaminases, while Vpu causes degradation of CD4 and promotes virus release by functionally inactivating the host factor BST-2. This chapter described techniques used for the characterization of Vif and Vpu and their functional interaction with host factors. Many of the techniques are, however, applicable to the functional analysis of other viral proteins. PMID:24158820

  18. Crystallization of accessory phases in magmas by local saturation adjacent to phenocrysts

    USGS Publications Warehouse

    Bacon, C.R.

    1989-01-01

    Accessory minerals commonly occur attached to or included in the major crystalline phases of felsic and some intermediate igneous rocks. Apatite is particularly common as inclusions, but Fe-Ti oxides, pyrrhotite, zircon, monazite, chevkinite and xenotime are also known from silicic rocks. Accessories may nucleate near the host crystal/ liquid interface as a result of local saturation owing to formation of a differentiated chemical boundary layer in which accessory mineral solubility would be lower than in the surrounding liquid. Differentiation of this boundary layer would be greatest adjacent to ferromagnesian phenocrysts, especially Fe-Ti oxides; it is with oxides that accessories are most commonly associated in rocks. A boundary layer may develop if the crystal grows more rapidly than diffusion can transport incorporated and rejected elements to and from the phenocryst. Diffusion must dominate over convection as a mode of mass transfer near the advancing crystal/liquid interface in order for a boundary layer to exist. Accumulation of essential structural constituent elements of accessory minerals owing to their slow diffusion in evolved silicate melt also may force local saturation, but this is not a process that applies to all cases. Local saturation is an attractive mechanism for enhancing fractionation during crystallization differentiation. If accessory minerals attached to or included in phenocrysts formed because of local saturation, their host phenocrysts must have grown rapidly when accessories nucleated in comparison to lifetimes of magma reservoirs. Some inconsistencies remain in a local saturation origin for accessory phases that cannot be evaluated without additional information. ?? 1989.

  19. Differential functioning of Bender Visual-Motor Gestalt Test items.

    PubMed

    Sisto, Fermino Fernandes; Dos Santos, Acácia Aparecida Angeli; Noronha, Ana Paula Porto

    2010-02-01

    Differential Item Functioning (DIF) refers to items that do not function the same way for comparable members of different groups. The present study focuses on analyzing and classifying sex-related differential item functioning in the Bender Visual-Motor Gestalt Test. Subjects were 1,052 children attending public schools (513 boys, 539 girls, ages 6-10 years). The protocols were scored using the Bender Graduated Scoring System, which evaluates only the distortion criterion using the Rasch logistic response model. The scoring system fit the Rasch model, although two items were found to be biased by sex. When analyzing differential functioning of items for boys and girls separately, the number of differentially functioning items was equal.

  20. Differentials of a State Reading Assessment: Item Functioning, Distractor Functioning, and Omission Frequency for Disability Categories

    ERIC Educational Resources Information Center

    Kato, Kentaro; Moen, Ross E.; Thurlow, Martha L.

    2009-01-01

    Large data sets from a state reading assessment for third and fifth graders were analyzed to examine differential item functioning (DIF), differential distractor functioning (DDF), and differential omission frequency (DOF) between students with particular categories of disabilities (speech/language impairments, learning disabilities, and emotional…

  1. Comparison theorems for neutral stochastic functional differential equations

    NASA Astrophysics Data System (ADS)

    Bai, Xiaoming; Jiang, Jifa

    2016-05-01

    The comparison theorems under Wu and Freedman's order are proved for neutral stochastic functional differential equations with finite or infinite delay whose drift terms satisfy the quasimonotone condition and diffusion term is the same.

  2. Generating functionals and Lagrangian partial differential equations

    SciTech Connect

    Vankerschaver, Joris; Liao, Cuicui; Leok, Melvin

    2013-08-15

    The main goal of this paper is to derive an alternative characterization of the multisymplectic form formula for classical field theories using the geometry of the space of boundary values. We review the concept of Type-I/II generating functionals defined on the space of boundary data of a Lagrangian field theory. On the Lagrangian side, we define an analogue of Jacobi's solution to the Hamilton–Jacobi equation for field theories, and we show that by taking variational derivatives of this functional, we obtain an isotropic submanifold of the space of Cauchy data, described by the so-called multisymplectic form formula. As an example of the latter, we show that Lorentz's reciprocity principle in electromagnetism is a particular instance of the multisymplectic form formula. We also define a Hamiltonian analogue of Jacobi's solution, and we show that this functional is a Type-II generating functional. We finish the paper by defining a similar framework of generating functions for discrete field theories, and we show that for the linear wave equation, we recover the multisymplectic conservation law of Bridges.

  3. Dynamic Ulnar Drift of Single Digit by an Anomalous Accessory Extensor Tendon.

    PubMed

    Smith, James R A; Amirfeyz, Rouin

    2017-03-01

    Descriptions of multiple extensor slips and accessory extensor tendons of the hand are extensively published in the contemporary literature. Despite their varied anatomy, accessory tendons seldom have a functional implication for the patient. We report a case detailing a previously undescribed accessory extensor tendon of the hand, which resulted unusually in an aberration in the mechanics of a single digit. This was explored and corrected surgically, resulting in an excellent outcome for the patient.

  4. Automobile accessories: Assessment and improvement

    SciTech Connect

    Jackson, M.

    1995-11-01

    With mandates and regulatory policies to meet both the California Air Resources Board (CARB) and the Partnership for a New Generation of Vehicles (PNGV), designing vehicles of the future will become a difficult task. As we look into the use of electric and hybrid vehicles, reduction of the required power demand by influential automobile components is necessary in order to obtain performance and range goals. Among those automobile components are accessories. Accessories have a profound impact on the range and mileage of future vehicles with limited amounts of energy or without power generating capabilities such as conventional vehicles. Careful assessment of major power consuming accessories helps us focus on those that need improvement and contributes to attainment of mileage and range goals for electric and hybrid vehicles.

  5. Fuzzy fractional functional differential equations under Caputo gH-differentiability

    NASA Astrophysics Data System (ADS)

    Hoa, Ngo Van

    2015-05-01

    In this paper the fuzzy fractional functional differential equations (FFFDEs) under the Caputo generalized Hukuhara differentiability are introduced. We study the existence and uniqueness results of solutions for FFFDEs under some suitable conditions. Also the solution to fuzzy fractional functional initial value problem under Caputo-type fuzzy fractional derivatives by a modified Adams-Bashforth-Moulton method (MABMM) is presented. The method is illustrated by solving some examples.

  6. Functional implications of differential chromosome banding.

    PubMed Central

    Hoehn, H

    1975-01-01

    Information on DNA content and banding patterns has been utilized in the construction of a novel ideogram of the human complement. Correspondence between certain features of this ideogram and the clinical record of human autosomal imbalance supports the idea that banding patterns reflect structural as well as functional heterogeneity of chromosomes. PMID:51585

  7. Intrapancreatic accessory spleen: A case report and review of the literature

    PubMed Central

    Guo, Wei; Han, Wei; Liu, Jun; Jin, Lan; Li, Jian-She; Zhang, Zhong-Tao; Wang, Yu

    2009-01-01

    Here, we report a case of intrapancreatic accessory spleen confirmed by pathologic diagnosis and discuss its differential diagnosis and surgical management with a review of the literature. PMID:19266611

  8. Accessory slips of the extensor digiti minimi.

    PubMed

    Li, Jing; Mao, Qing Hua

    2014-01-01

    During the educational dissection of a 69-year-old Chinese male cadaver, an extensor digiti minimi (EDM) with five slips on the right hand was discovered. Except for the two slips of the little finger, the two radial slips were inserted into the dorsal aponeurosis of the middle finger and the ring finger, respectively. The middle slip was connected to the junctura tendinum in the fourth intermetacarpal spaces. Variations in this region are of paramount importance for the reconstructive surgeons, who may utilize the accessory slips to restore functional capacity of the fingers.

  9. Teaching Techniques for Accessory Percussion

    ERIC Educational Resources Information Center

    Micallef, Ken

    2007-01-01

    Everyone is familiar with the main percussion instruments of the contemporary orchestra: bass drum, snare drum, suspended cymbal, vibraphone, and timpani. But as source material broadens, so do the demands placed on the percussion section. Accessory, or auxiliary percussion, can make the difference between a typical rendition of a well-known piece…

  10. Intrahepatic accessory spleen: imaging features.

    PubMed

    Izzo, Luciano; Caputo, Maria; Galati, Gaspare

    2004-06-01

    The authors present a case report of a 60-year-old man with a hepatic unknown mass. For diagnosis, they used ECO, CT (with and without contrast), MR (with and without contrast) and an ultrasound-assisted percutaneous lesion biopsy. Thus the mass-lesion in the liver appeared to be an intrahepatic accessory spleen in a patient afflicted with chronic hepatitis.

  11. Decisions that Make a Difference in Detecting Differential Item Functioning

    ERIC Educational Resources Information Center

    Sireci, Stephen G.; Rios, Joseph A.

    2013-01-01

    There are numerous statistical procedures for detecting items that function differently across subgroups of examinees that take a test or survey. However, in endeavouring to detect items that may function differentially, selection of the statistical method is only one of many important decisions. In this article, we discuss the important decisions…

  12. 14 CFR 25.1163 - Powerplant accessories.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Powerplant accessories. (a) Each engine mounted accessory must— (1) Be approved for mounting on the engine involved; (2) Use the provisions on the engine for mounting; and (3) Be sealed to prevent contamination of the engine oil system and the accessory system. (b) Electrical equipment subject to arcing or...

  13. Evaluation of a differentiation model of preschoolers' executive functions.

    PubMed

    Howard, Steven J; Okely, Anthony D; Ellis, Yvonne G

    2015-01-01

    Despite the prominent role of executive functions in children's emerging competencies, there remains debate regarding the structure and development of executive functions. In an attempt to reconcile these discrepancies, a differentiation model of executive function development was evaluated in the early years using 6-month age groupings. Specifically, 281 preschoolers completed measures of working memory, inhibition, and shifting. Results contradicted suggestions that executive functions follow a single trajectory of progressive separation in childhood, instead suggesting that these functions may undergo a period of integration in the preschool years. These results highlight potential problems with current practices and theorizing in executive function research.

  14. Macrophage differentiation and function in atherosclerosis; opportunities for therapeutic intervention?

    PubMed Central

    Williams, Howell J.; Fisher, Edward A.; Greaves, David R.

    2013-01-01

    The macrophage is exquisitely sensitive to its microenvironment, as demonstrated primarily through in vitro study. Changes in macrophage phenotype and function within the atherosclerotic plaque have profound consequences for plaque biology, including rupture and arterial thrombosis leading to clinical events such as myocardial infarction. We review the evidence for dynamic changes in macrophage numbers and macrophage differentiation within the atherosclerotic plaque microenvironment and discuss potential approaches to target macrophage differentiation for therapeutic benefit in cardiovascular disease. PMID:22572544

  15. Compartmentalized function through cell differentiation in filamentous cyanobacteria.

    PubMed

    Flores, Enrique; Herrero, Antonia

    2010-01-01

    Within the wide biodiversity that is found in the bacterial world, Cyanobacteria represents a unique phylogenetic group that is responsible for a key metabolic process in the biosphere - oxygenic photosynthesis - and that includes representatives exhibiting complex morphologies. Many cyanobacteria are multicellular, growing as filaments of cells in which some cells can differentiate to carry out specialized functions. These differentiated cells include resistance and dispersal forms as well as a metabolically specialized form that is devoted to N(2) fixation, known as the heterocyst. In this Review we address cyanobacterial intercellular communication, the supracellular structure of the cyanobacterial filament and the basic principles that govern the process of heterocyst differentiation.

  16. Zonal organization of the mammalian main and accessory olfactory systems.

    PubMed Central

    Mori, K; von Campenhause, H; Yoshihara, Y

    2000-01-01

    Zonal organization is one of the characteristic features observed in both main and accessory olfactory systems. In the main olfactory system, most of the odorant receptors are classified into four groups according to their zonal expression patterns in the olfactory epithelium. Each group of odorant receptors is expressed by sensory neurons distributed within one of four circumscribed zones. Olfactory sensory neurons in a given zone of the epithelium project their axons to the glomeruli in a corresponding zone of the main olfactory bulb. Glomeruli in the same zone tend to represent similar odorant receptors having similar tuning specificity to odorants. Vomeronasal receptors (or pheromone receptors) are classified into two groups in the accessory olfactory system. Each group of receptors is expressed by vomeronasal sensory neurons in either the apical or basal zone of the vomeronasal epithelium. Sensory neurons in the apical zone project their axons to the rostral zone of the accessory olfactory bulb and form synaptic connections with mitral tufted cells belonging to the rostral zone. Signals originated from basal zone sensory neurons are sent to mitral tufted cells in the caudal zone of the accessory olfactory bulb. We discuss functional implications of the zonal organization in both main and accessory olfactory systems. PMID:11205342

  17. The LIM protein LIMD1 influences osteoblast differentiation and function

    SciTech Connect

    Luderer, Hilary F.; Bai Shuting; Longmore, Gregory D.

    2008-09-10

    The balance between bone resorption and bone formation involves the coordinated activities of osteoblasts and osteoclasts. Communication between these two cell types is essential for maintenance of normal bone homeostasis; however, the mechanisms regulating this cross talk are not completely understood. Many factors that mediate differentiation and function of both osteoblasts and osteoclasts have been identified. The LIM protein Limd1 has been implicated in the regulation of stress osteoclastogenesis through an interaction with the p62/sequestosome protein. Here we show that Limd1 also influences osteoblast progenitor numbers, differentiation, and function. Limd1{sup -/-} calvarial osteoblasts display increased mineralization and accelerated differentiation. While no significant differences in osteoblast number or function were detected in vivo, bone marrow stromal cells isolated from Limd1{sup -/-} mice contain significantly more osteoblast progenitors compared to wild type controls when cultured ex vivo. Furthermore, we observed a significant increase in nuclear {beta}-catenin staining in differentiating Limd1{sup -/-} calvarial osteoblasts suggesting that Limd1 is a negative regulator of canonical Wnt signaling in osteoblasts. These results demonstrate that Limd1 influences not only stress osteoclastogenesis but also osteoblast function and osteoblast progenitor commitment. Together, these data identify Limd1 as a novel regulator of both bone osetoclast and bone osteoblast development and function.

  18. Pharmacological Bypass of Cockayne Syndrome B Function in Neuronal Differentiation

    PubMed Central

    Wang, Yuming; Jones-Tabah, Jace; Chakravarty, Probir; Stewart, Aengus; Muotri, Alysson; Laposa, Rebecca R.; Svejstrup, Jesper Q.

    2016-01-01

    Summary Cockayne syndrome (CS) is a severe neurodevelopmental disorder characterized by growth abnormalities, premature aging, and photosensitivity. Mutation of Cockayne syndrome B (CSB) affects neuronal gene expression and differentiation, so we attempted to bypass its function by expressing downstream target genes. Intriguingly, ectopic expression of Synaptotagmin 9 (SYT9), a key component of the machinery controlling neurotrophin release, bypasses the need for CSB in neuritogenesis. Importantly, brain-derived neurotrophic factor (BDNF), a neurotrophin implicated in neuronal differentiation and synaptic modulation, and pharmacological mimics such as 7,8-dihydroxyflavone and amitriptyline can compensate for CSB deficiency in cell models of neuronal differentiation as well. SYT9 and BDNF are downregulated in CS patient brain tissue, further indicating that sub-optimal neurotrophin signaling underlies neurological defects in CS. In addition to shedding light on cellular mechanisms underlying CS and pointing to future avenues for pharmacological intervention, these data suggest an important role for SYT9 in neuronal differentiation. PMID:26972010

  19. Locally vascularized pelvic accessory spleen.

    PubMed

    Iorio, F; Frantellizzi, V; Drudi, Francesco M; Maghella, F; Liberatore, M

    2016-01-01

    Polysplenism and accessory spleen are congenital, usually asymptomatic anomalies. A rare case of polysplenism with ectopic spleen in pelvis of a 67-year-old, Caucasian female is reported here. A transvaginal ultrasound found a soft well-defined homogeneous and vascularized mass in the left pelvis. Patient underwent MRI evaluation and contrast-CT abdominal scan: images with parenchymal aspect, similar to spleen were obtained. Abdominal scintigraphy with 99mTc-albumin nanocolloid was performed and pelvic region was studied with planar scans and SPECT. The results showed the presence of an uptake area of the radiopharmaceutical in the pelvis, while the spleen was normally visualized. These findings confirmed the presence of an accessory spleen with an artery originated from the aorta and a vein that joined with the superior mesenteric vein. To our knowledge, in the literature, there is just only one case of a true ectopic, locally vascularized spleen in the pelvis.

  20. On Parameter Differentiation for Integral Representations of Associated Legendre Functions

    NASA Astrophysics Data System (ADS)

    Cohl, Howard S.

    2011-05-01

    For integral representations of associated Legendre functions in terms of modified Bessel functions, we establish justification for differentiation under the integral sign with respect to parameters. With this justification, derivatives for associated Legendre functions of the first and second kind with respect to the degree are evaluated at odd-half-integer degrees, for general complex-orders, and derivatives with respect to the order are evaluated at integer-orders, for general complex-degrees. We also discuss the properties of the complex function f: C\\{-1,1}→C given by f(z)=z/((z+1)1/2(z-1)1/2).

  1. MIMIC Methods for Assessing Differential Item Functioning in Polytomous Items

    ERIC Educational Resources Information Center

    Wang, Wen-Chung; Shih, Ching-Lin

    2010-01-01

    Three multiple indicators-multiple causes (MIMIC) methods, namely, the standard MIMIC method (M-ST), the MIMIC method with scale purification (M-SP), and the MIMIC method with a pure anchor (M-PA), were developed to assess differential item functioning (DIF) in polytomous items. In a series of simulations, it appeared that all three methods…

  2. Three Classes of Nonparametric Differential Step Functioning Effect Estimators

    ERIC Educational Resources Information Center

    Penfield, Randall D.

    2008-01-01

    The examination of measurement invariance in polytomous items is complicated by the possibility that the magnitude and sign of lack of invariance may vary across the steps underlying the set of polytomous response options, a concept referred to as differential step functioning (DSF). This article describes three classes of nonparametric DSF effect…

  3. The epigenetic landscape of mammary gland development and functional differentiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most of the development and functional differentiation in the mammary gland occur after birth. Epigenetics is defined as the stable alterations in gene expression potential that arise during development and proliferation. Epigenetic changes are mediated at the biochemical level by the chromatin conf...

  4. Differential Item Functioning: Performance by Sex on Reading Comprehension Tests.

    ERIC Educational Resources Information Center

    Gafni, Naomi

    Items in the verbal (Hebrew and English) sections of the Psychometric Entrance Test (PET) administered for university admission in Israel were studied for differential item functioning (DIF) between the sexes. Analyses were conducted for 4,354 males and 4,901 females taking Form 3 of the PET in April 1984, and 3,786 males and 3,815 females taking…

  5. Effect of Differential Item Functioning on Test Equating

    ERIC Educational Resources Information Center

    Kabasakal, Kübra Atalay; Kelecioglu, Hülya

    2015-01-01

    This study examines the effect of differential item functioning (DIF) items on test equating through multilevel item response models (MIRMs) and traditional IRMs. The performances of three different equating models were investigated under 24 different simulation conditions, and the variables whose effects were examined included sample size, test…

  6. Using Mixed Methods to Interpret Differential Item Functioning

    ERIC Educational Resources Information Center

    Benítez, Isabel; Padilla, José-Luis; Hidalgo Montesinos, María Dolores; Sireci, Stephen G.

    2016-01-01

    Analysis of differential item functioning (DIF) is often used to determine if cross-lingual assessments are equivalent across languages. However, evidence on the causes of cross-lingual DIF is still evasive. Expert appraisal is a qualitative method useful for obtaining detailed information about problematic elements in the different linguistic…

  7. Exploring Crossing Differential Item Functioning by Gender in Mathematics Assessment

    ERIC Educational Resources Information Center

    Ong, Yoke Mooi; Williams, Julian; Lamprianou, Iasonas

    2015-01-01

    The purpose of this article is to explore crossing differential item functioning (DIF) in a test drawn from a national examination of mathematics for 11-year-old pupils in England. An empirical dataset was analyzed to explore DIF by gender in a mathematics assessment. A two-step process involving the logistic regression (LR) procedure for…

  8. Real and Artificial Differential Item Functioning in Polytomous Items

    ERIC Educational Resources Information Center

    Andrich, David; Hagquist, Curt

    2015-01-01

    Differential item functioning (DIF) for an item between two groups is present if, for the same person location on a variable, persons from different groups have different expected values for their responses. Applying only to dichotomously scored items in the popular Mantel-Haenszel (MH) method for detecting DIF in which persons are classified by…

  9. Applying a Mixed Methods Framework to Differential Item Function Analyses

    ERIC Educational Resources Information Center

    Hitchcock, John H.; Johanson, George A.

    2015-01-01

    Understanding the reason(s) for Differential Item Functioning (DIF) in the context of measurement is difficult. Although identifying potential DIF items is typically a statistical endeavor, understanding the reasons for DIF (and item repair or replacement) might require investigations that can be informed by qualitative work. Such work is…

  10. Detection of Differential Item Functioning Using the Lasso Approach

    ERIC Educational Resources Information Center

    Magis, David; Tuerlinckx, Francis; De Boeck, Paul

    2015-01-01

    This article proposes a novel approach to detect differential item functioning (DIF) among dichotomously scored items. Unlike standard DIF methods that perform an item-by-item analysis, we propose the "LR lasso DIF method": logistic regression (LR) model is formulated for all item responses. The model contains item-specific intercepts,…

  11. Analysis of Differential Item Functioning in the NAEP History Assessment.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; Ercikan, Kadriye

    1989-01-01

    The Mantel-Haenszel approach for investigating differential item functioning (DIF) was applied to United States history items within the 1986 National Assessment of Educational Progress administered to 7,812 11th graders. DIF analyses were based on responses of 7,743 11th graders. Results concerning sex and racial differences and ethnicity are…

  12. Analysis of Differential Item Functioning in the NAEP History Assessment.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; Ercikan, Kadriye

    The Mantel-Haenszel approach for investigating differential item functioning (DIF) was applied to U.S. history items that were administered as part of the National Assessment of Educational Progress (NAEP). DIF analyses were based on the responses of 7,743 students in grade 11. On some items, Blacks, Hispanics, and females performed more poorly…

  13. Assessment of Differential Item Functioning for Performance Tasks.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; And Others

    1993-01-01

    Two extensions of the Mantel Haenszel procedure that may be useful in assessing differential item functioning (DIF) are explored. Simulation results showed that, for both inferential procedures, the studied item should be included in the matching variable, as in the dichotomous case. (SLD)

  14. Evaluating the Magnitude of Differential Item Functioning in Polytomous Items.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; Thayer, Dorothy T.

    1996-01-01

    Two possible standard error formulas for the polytomous differential item functioning index proposed by N. J. Dorans and A. P. Schmitt (1991) were derived. These standard errors, and associated hypothesis-testing procedures, were evaluated through simulated data. The standard error that performed better is based on N. Mantel's (1963)…

  15. Testing for Differential Item Functioning with Measures of Partial Association

    ERIC Educational Resources Information Center

    Woods, Carol M.

    2009-01-01

    Differential item functioning (DIF) occurs when an item on a test or questionnaire has different measurement properties for one group of people versus another, irrespective of mean differences on the construct. There are many methods available for DIF assessment. The present article is focused on indices of partial association. A family of average…

  16. Effect of Multiple Testing Adjustment in Differential Item Functioning Detection

    ERIC Educational Resources Information Center

    Kim, Jihye; Oshima, T. C.

    2013-01-01

    In a typical differential item functioning (DIF) analysis, a significance test is conducted for each item. As a test consists of multiple items, such multiple testing may increase the possibility of making a Type I error at least once. The goal of this study was to investigate how to control a Type I error rate and power using adjustment…

  17. Master integrals for splitting functions from differential equations in QCD

    NASA Astrophysics Data System (ADS)

    Gituliar, Oleksandr

    2016-02-01

    A method for calculating phase-space master integrals for the decay process 1 → n masslesspartonsinQCDusingintegration-by-partsanddifferentialequationstechniques is discussed. The method is based on the appropriate choice of the basis for master integrals which leads to significant simplification of differential equations. We describe an algorithm how to construct the desirable basis, so that the resulting system of differential equations can be recursively solved in terms of (G) HPLs as a series in the dimensional regulator ɛ to any order. We demonstrate its power by calculating master integrals for the NLO time-like splitting functions and discuss future applications of the proposed method at the NNLO precision.

  18. [FUNCTIONAL DIFFERENTIATION IN BRYOZOAN COLONY: A PROTEOMIC ANALYSIS].

    PubMed

    Kutyumov, V A; Maltseva, A L; Kotenko, N; Ostrovsky, A N

    2016-01-01

    Bryozoans are typical modular organisms. They consist of repetitive structural units, the zooids. Bryozoan colonies grow by zooidal budding, with the distribution pattern of the budding loci underlying the diversity of colony forms. Budding is usually restricted to the zooids at the periphery of the colony, which form a "growing edge" or local terminal growth zones. Non-budding parts of the colony can be functionally subdivided, too. In many species colonies consists of regular, often repetitive zones of feeding and non-feeding modules, associated with a periodical degeneration and regeneration of the polypide, retractile tentacle crown with a gut and the accompanying musculature. So, there is functional differentiation in bryozoan colonies but its mechanisms are unknown. Presumably, budding and/or polypide recycling in different colony parts are induced or inhibited by certain determinants of functional specialization. An effective tool of their identification is the comparison of proteomes of functionally different zones. Here we report the results of proteomic analysis of three bryozoan species from the White Sea, which have a different colony form: Flustrellidra hispida, Terminoflustra membranaceotruncata and Securiflustra securifrons. Using differential two-dimensional electrophoresis (2D-DIGE), we compared proteomes of the growing edge and the zones consisting of feeding and non-feeding zooids in these species. We estimated the overall proteome variability, revealed proteins whose relative abundance gradually changed along the proximal-distal colony axis and suggested that they might be involved in the functional differentiation of the colony.

  19. Differential Expression and Network Inferences through Functional Data Modeling

    PubMed Central

    Telesca, Donatello; Inoue, Lurdes Y.T.; Neira, Mauricio; Etzioni, Ruth; Gleave, Martin; Nelson, Colleen

    2010-01-01

    Time–course microarray data consist of mRNA expression from a common set of genes collected at different time points. Such data are thought to reflect underlying biological processes developing over time. In this article we propose a model that allows us to examine differential expression and gene network relationships using time course microarray data. We model each gene expression profile as a random functional transformation of the scale, amplitude and phase of a common curve. Inferences about the gene–specific amplitude parameters allow us to examine differential gene expression. Inferences about measures of functional similarity based on estimated time transformation functions allow us to examine gene networks while accounting for features of the gene expression profiles. We discuss applications to simulated data as well as to microarray data on prostate cancer progression. PMID:19053995

  20. Differentiation of Spermatogonia Stem Cells into Functional Mature Neurons Characterized with Differential Gene Expression.

    PubMed

    Bojnordi, Maryam Nazm; Azizi, Hossein; Skutella, Thomas; Movahedin, Mansoureh; Pourabdolhossein, Fereshteh; Shojaei, Amir; Hamidabadi, Hatef Ghasemi

    2016-09-19

    Transplantation of embryonic stem cells (ESCs) is a promising therapeutic approach for the treatment of neurodegenerative diseases. However, ESCs are not usable clinically due to immunological and ethical limitations. The identification of an alternative safe cell source opens novel options via autologous transplantation in neuro-regeneration circumventing these problems. Here, we examined the neurogenic capacity of embryonic stem-like cells (ES-like cells) derived from the testis using neural growth factor inducers and utilized them to generate functional mature neurons. The neuronal differentiation of ES-like cells is induced in three stages. Stage 1 is related to embryoid body (EB) formation. To induce neuroprogenitor cells, EBs were cultured in the presence of retinoic acid, N2 supplement and fibroblast growth factor followed by culturing in a neurobasal medium containing B27, N2 supplements for additional 10 days, to allow the maturation and development of neuronal progenitor cells. The neurogenic differentiation was confirmed by immunostaining for markers of mature neurons. The differentiated neurons were positive for Tuj1 and Tau1. Real-time PCR dates indicated the expression of Nestin and Neuro D (neuroprogenitor markers) in induced cells at the second stage of the differentiation protocol. The differentiated mature neurons exhibited the specific neuron markers Map2 and β-tubulin. The functional maturity of neurons was confirmed by an electrophysiological analysis of passive and active neural membrane properties. These findings indicated a differentiation capacity of ES-like cells derived from the testis to functionally mature neurons, which proposes them as a novel cell source for neuroregenerative medicine.

  1. Limited role of functional differentiation in early diversification of animals

    PubMed Central

    Knope, M.L.; Heim, N.A.; Frishkoff, L.O.; Payne, J.L.

    2015-01-01

    The origin of most animal phyla and classes during the Cambrian explosion has been hypothesized to represent an ‘early burst’ of evolutionary exploration of functional ecological possibilities. However, the ecological history of marine animals has yet to be fully quantified, preventing an assessment of the early-burst model for functional ecology. Here we use ecological assignments for 18,621 marine animal genera to assess the relative timing of functional differentiation versus taxonomic diversification from the Cambrian to the present day. We find that functional diversity increased more slowly than would be expected given the history of taxonomic diversity. Contrary to previous inferences of rapid ecological differentiation from the early appearances of all well-fossilized phyla and classes, explicit coding of functional characteristics demonstrates that Cambrian genera occupied comparatively few modes of life. Functional diversity increased in the Ordovician and, especially, during the recoveries from the end-Permian and end-Cretaceous mass extinctions. Permanent shifts in the relationship between functional and taxonomic diversity following the era-bounding extinctions indicates a critical role for these biotic crises in coupling taxonomic and functional diversity. PMID:25737406

  2. Limited role of functional differentiation in early diversification of animals.

    PubMed

    Knope, M L; Heim, N A; Frishkoff, L O; Payne, J L

    2015-03-04

    The origin of most animal phyla and classes during the Cambrian explosion has been hypothesized to represent an 'early burst' of evolutionary exploration of functional ecological possibilities. However, the ecological history of marine animals has yet to be fully quantified, preventing an assessment of the early-burst model for functional ecology. Here we use ecological assignments for 18,621 marine animal genera to assess the relative timing of functional differentiation versus taxonomic diversification from the Cambrian to the present day. We find that functional diversity increased more slowly than would be expected given the history of taxonomic diversity. Contrary to previous inferences of rapid ecological differentiation from the early appearances of all well-fossilized phyla and classes, explicit coding of functional characteristics demonstrates that Cambrian genera occupied comparatively few modes of life. Functional diversity increased in the Ordovician and, especially, during the recoveries from the end-Permian and end-Cretaceous mass extinctions. Permanent shifts in the relationship between functional and taxonomic diversity following the era-bounding extinctions indicates a critical role for these biotic crises in coupling taxonomic and functional diversity.

  3. Estimation and Inference of Directionally Differentiable Functions: Theory and Applications

    NASA Astrophysics Data System (ADS)

    Fang, Zheng

    This dissertation addresses a large class of irregular models in economics and statistics -- settings in which the parameters of interest take the form φ(theta 0), where φ is a known directionally differentiable function and theta 0 is estimated by thetan. Chapter 1 provides a tractable framework for conducting inference, Chapter 2 focuses on optimality of estimation, and Chapter 3 applies the developed theory to construct a test whether a Hilbert space valued parameter belongs to a convex set and to derive the uniform weak convergence of the Grenander distribution function -- i.e. the least concave majorant of the empirical distribution function -- under minimal assumptions.

  4. Differentiable but exact formulation of density-functional theory.

    PubMed

    Kvaal, Simen; Ekström, Ulf; Teale, Andrew M; Helgaker, Trygve

    2014-05-14

    The universal density functional F of density-functional theory is a complicated and ill-behaved function of the density-in particular, F is not differentiable, making many formal manipulations more complicated. While F has been well characterized in terms of convex analysis as forming a conjugate pair (E, F) with the ground-state energy E via the Hohenberg-Kohn and Lieb variation principles, F is nondifferentiable and subdifferentiable only on a small (but dense) subset of its domain. In this article, we apply a tool from convex analysis, Moreau-Yosida regularization, to construct, for any ε > 0, pairs of conjugate functionals ((ε)E, (ε)F) that converge to (E, F) pointwise everywhere as ε → 0(+), and such that (ε)F is (Fréchet) differentiable. For technical reasons, we limit our attention to molecular electronic systems in a finite but large box. It is noteworthy that no information is lost in the Moreau-Yosida regularization: the physical ground-state energy E(v) is exactly recoverable from the regularized ground-state energy (ε)E(v) in a simple way. All concepts and results pertaining to the original (E, F) pair have direct counterparts in results for ((ε)E, (ε)F). The Moreau-Yosida regularization therefore allows for an exact, differentiable formulation of density-functional theory. In particular, taking advantage of the differentiability of (ε)F, a rigorous formulation of Kohn-Sham theory is presented that does not suffer from the noninteracting representability problem in standard Kohn-Sham theory.

  5. Differentiable but exact formulation of density-functional theory

    SciTech Connect

    Kvaal, Simen Ekström, Ulf; Helgaker, Trygve; Teale, Andrew M.

    2014-05-14

    The universal density functional F of density-functional theory is a complicated and ill-behaved function of the density—in particular, F is not differentiable, making many formal manipulations more complicated. While F has been well characterized in terms of convex analysis as forming a conjugate pair (E, F) with the ground-state energy E via the Hohenberg–Kohn and Lieb variation principles, F is nondifferentiable and subdifferentiable only on a small (but dense) subset of its domain. In this article, we apply a tool from convex analysis, Moreau–Yosida regularization, to construct, for any ε > 0, pairs of conjugate functionals ({sup ε}E, {sup ε}F) that converge to (E, F) pointwise everywhere as ε → 0{sup +}, and such that {sup ε}F is (Fréchet) differentiable. For technical reasons, we limit our attention to molecular electronic systems in a finite but large box. It is noteworthy that no information is lost in the Moreau–Yosida regularization: the physical ground-state energy E(v) is exactly recoverable from the regularized ground-state energy {sup ε}E(v) in a simple way. All concepts and results pertaining to the original (E, F) pair have direct counterparts in results for ({sup ε}E, {sup ε}F). The Moreau–Yosida regularization therefore allows for an exact, differentiable formulation of density-functional theory. In particular, taking advantage of the differentiability of {sup ε}F, a rigorous formulation of Kohn–Sham theory is presented that does not suffer from the noninteracting representability problem in standard Kohn–Sham theory.

  6. Differentiable but exact formulation of density-functional theory

    NASA Astrophysics Data System (ADS)

    Kvaal, Simen; Ekström, Ulf; Teale, Andrew M.; Helgaker, Trygve

    2014-05-01

    The universal density functional F of density-functional theory is a complicated and ill-behaved function of the density—in particular, F is not differentiable, making many formal manipulations more complicated. While F has been well characterized in terms of convex analysis as forming a conjugate pair (E, F) with the ground-state energy E via the Hohenberg-Kohn and Lieb variation principles, F is nondifferentiable and subdifferentiable only on a small (but dense) subset of its domain. In this article, we apply a tool from convex analysis, Moreau-Yosida regularization, to construct, for any ɛ > 0, pairs of conjugate functionals (ɛE, ɛF) that converge to (E, F) pointwise everywhere as ɛ → 0+, and such that ɛF is (Fréchet) differentiable. For technical reasons, we limit our attention to molecular electronic systems in a finite but large box. It is noteworthy that no information is lost in the Moreau-Yosida regularization: the physical ground-state energy E(v) is exactly recoverable from the regularized ground-state energy ɛE(v) in a simple way. All concepts and results pertaining to the original (E, F) pair have direct counterparts in results for (ɛE, ɛF). The Moreau-Yosida regularization therefore allows for an exact, differentiable formulation of density-functional theory. In particular, taking advantage of the differentiability of ɛF, a rigorous formulation of Kohn-Sham theory is presented that does not suffer from the noninteracting representability problem in standard Kohn-Sham theory.

  7. Engine starter and accessory drive system

    SciTech Connect

    Stockton, T.R.

    1986-10-07

    An engine starter and accessory drive system is described which consists of: an accessory drive means; a planetary gearset having a sun gear driveably connected to the accessory drive means, a ring gear, a carrier and planet pinions rotatably mounted on the carrier, fixed to the engine crankshaft, meshing with the sun gear and with the ring gear; means for holding the ring gear against rotation; and a starter motor and first clutch means for providing a one-way driving connection between the motor and the accessory drive means.

  8. Advanced Accessory Power Supply Topologies

    SciTech Connect

    Marlino, L.D.

    2010-06-15

    This Cooperative Research and Development Agreement (CRADA) began December 8, 2000 and ended September 30, 2009. The total funding provided by the Participant (General Motors Advanced Technology Vehicles [GM]) during the course of the CRADA totaled $1.2M enabling the Contractor (UT-Battelle, LLC [Oak Ridge National Laboratory, a.k.a. ORNL]) to contribute significantly to the joint project. The initial task was to work with GM on the feasibility of developing their conceptual approach of modifying major components of the existing traction inverter/drive to develop low cost, robust, accessory power. Two alternate methods for implementation were suggested by ORNL and both were proven successful through simulations and then extensive testing of prototypes designed and fabricated during the project. This validated the GM overall concept. Moreover, three joint U.S. patents were issued and subsequently licensed by GM. After successfully fulfilling the initial objective, the direction and duration of the CRADA was modified and GM provided funding for two additional tasks. The first new task was to provide the basic development for implementing a cascaded inverter technology into hybrid vehicles (including plug-in hybrid, fuel cell, and electric). The second new task was to continue the basic development for implementing inverter and converter topologies and new technology assessments for hybrid vehicle applications. Additionally, this task was to address the use of high temperature components in drive systems. Under this CRADA, ORNL conducted further research based on GM’s idea of using the motor magnetic core and windings to produce bidirectional accessory power supply that is nongalvanically coupled to the terminals of the high voltage dc-link battery of hybrid vehicles. In order not to interfere with the motor’s torque, ORNL suggested to use the zero-sequence, highfrequency harmonics carried by the main fundamental motor current for producing the accessory power

  9. Non-functioning Well Differentiated Endocrine Carcinoma of the Pancreas

    PubMed Central

    Terada, Tadashi

    2009-01-01

    The author reports a typical but rare case of non-functioning well differentiated endocrine carcinoma of the pancreas. A 67-year-old man was admitted to our hospital because of abdominal pain. No hormone-related symptoms were recognized. He has no familiar history of pancreatic neoplasms. Various imaging modalities including US, CT and MRI revealed a tumor of the pancreatic body. Distal pancreatectomy and splenectomy were performed. A solid well demarcated tumor was present in the pancreatic body. Peripancreatic lymph nodes showed marked swelling suggestive of metastases. Immunohistyochemically, tumor cells were positive for cytokeratin, synaptophysin, neuron-specific enolase, and CD56; they were negative for chromogranin, gastrin, glucagon, somatostatin, pancreatic polypeptide, and vasoactive intestinal polypeptide. The pathological diagnosis was non-functioning well differentiated endocrine carcinoma of the pancreas. PMID:27990210

  10. Inorganic arsenic impairs differentiation and functions of human dendritic cells

    SciTech Connect

    Macoch, Mélinda; Morzadec, Claudie; Fardel, Olivier; Vernhet, Laurent

    2013-01-15

    Experimental studies have demonstrated that the antileukemic trivalent inorganic arsenic prevents the development of severe pro-inflammatory diseases mediated by excessive Th1 and Th17 cell responses. Differentiation of Th1 and Th17 subsets is mainly regulated by interleukins (ILs) secreted from dendritic cells (DCs) and the ability of inorganic arsenic to impair interferon-γ and IL-17 secretion by interfering with the physiology of DCs is unknown. In the present study, we demonstrate that high concentrations of sodium arsenite (As(III), 1–2 μM) clinically achievable in plasma of arsenic-treated patients, block differentiation of human peripheral blood monocytes into immature DCs (iDCs) by inducing their necrosis. Differentiation of monocytes in the presence of non-cytotoxic concentrations of As(III) (0.1 to 0.5 μM) only slightly impacts endocytotic activity of iDCs or expression of co-stimulatory molecules in cells activated with lipopolysaccharide. However, this differentiation in the presence of As(III) strongly represses secretion of IL-12p70 and IL-23, two major regulators of Th1 and Th17 activities, from iDCs stimulated with different toll-like receptor (TLR) agonists in metalloid-free medium. Such As(III)-exposed DCs also exhibit reduced mRNA levels of IL12A and/or IL12B genes when activated with TLR agonists. Finally, differentiation of monocytes with non-cytotoxic concentrations of As(III) subsequently reduces the ability of activated DCs to stimulate the release of interferon-γ and IL-17 from Th cells. In conclusion, our results demonstrate that clinically relevant concentrations of inorganic arsenic markedly impair in vitro differentiation and functions of DCs, which may contribute to the putative beneficial effects of the metalloid towards inflammatory autoimmune diseases. Highlights: ► Inorganic arsenic impairs differentiation and functions of human dendritic cells (DCs) ► Arsenite (> 1 μM) blocks differentiation of dendritic cells by

  11. Exp-function method for solving fractional partial differential equations.

    PubMed

    Zheng, Bin

    2013-01-01

    We extend the Exp-function method to fractional partial differential equations in the sense of modified Riemann-Liouville derivative based on nonlinear fractional complex transformation. For illustrating the validity of this method, we apply it to the space-time fractional Fokas equation and the nonlinear fractional Sharma-Tasso-Olver (STO) equation. As a result, some new exact solutions for them are successfully established.

  12. Hunting for eruption ages in accessory minerals

    NASA Astrophysics Data System (ADS)

    Vazquez, J. A.

    2012-12-01

    A primary goal in geochronology is to provide precise and accurate ages for tephras that serve as chronostratigraphic markers for constraining the timing and rates of volcanism, sedimentation, climate change, and catastrophic events in Earth history. Zircon remains the most versatile accessory mineral for dating silicic tephras due to its common preservation in distal pyroclastic deposits, as well as the robustness of its U-Pb and U-series systems even after host materials have been hydrothermally altered or weathered. Countless studies document that zircon may be complexly zoned in age due to inheritance, contamination, recycling of antecrysts, protracted crystallization in long-lived magma reservoirs, or any combination of these. Other accessory minerals such as allanite or chevkinite can retain similar records of protracted crystallization. If the goal is to date the durations of magmatic crystallization, differentiation, and/or magma residence, then these protracted chronologies within and between accessory minerals are a blessing. However, if the goal is to date the timing of eruption with high precision, i.e., absolute ages with millennial-scale uncertainties, then this age zoning is a curse. Observations from ion microprobe 238U-230Th dating of Pleistocene zircon and allanite provide insight into the record of near-eruption crystallization in accessory minerals and serve as a guide for high-precision whole-crystal dating. Although imprecise relative to conventional techniques, ion probe analysis allows high-spatial resolution 238U-230Th dating that can document multi-millennial age distributions at the crystal scale. Analysis of unpolished rims and continuous depth profiling of zircon from small and large volume eruptions (e.g., Coso, Mono Craters, Yellowstone) reveals that the final several micrometers of crystallization often yield ages that are indistinguishable from associated eruption ages from the 40Ar/39Ar or (U-Th)/He methods. Using this approach, we

  13. Regulation of T Cell Differentiation and Function by EZH2

    PubMed Central

    Karantanos, Theodoros; Christofides, Anthos; Bardhan, Kankana; Li, Lequn; Boussiotis, Vassiliki A.

    2016-01-01

    The enhancer of zeste homolog 2 (EZH2), one of the polycomb-group proteins, is the catalytic subunit of Polycomb-repressive complex 2 (PRC2) and induces the trimethylation of the histone H3 lysine 27 (H3K27me3) promoting epigenetic gene silencing. EZH2 contains a SET domain promoting the methyltransferase activity, while the three other protein components of PRC2, namely EED, SUZ12, and RpAp46/48, induce compaction of the chromatin permitting EZH2 enzymatic activity. Numerous studies highlight the role of this evolutionary conserved protein as a master regulator of differentiation in humans involved in the repression of the homeotic gene and the inactivation of X-chromosome. Through its effects in the epigenetic regulation of critical genes, EZH2 has been strongly linked to cell cycle progression, stem cell pluripotency, and cancer biology, being currently at the cutting edge of research. Most recently, EZH2 has been associated with hematopoietic stem cell proliferation and differentiation, thymopoiesis and lymphopoiesis. Several studies have evaluated the role of EZH2 in the regulation of T cell differentiation and plasticity as well as its implications in the development of autoimmune diseases and graft-versus-host disease (GVHD). The aim of this review is to summarize the current knowledge regarding the role of EZH2 in the regulation of the differentiation and function of T cells focusing on possible applications in various immune-mediated conditions, including autoimmune disorders and GVHD. PMID:27199994

  14. The sea lamprey has a primordial accessory olfactory system

    PubMed Central

    2013-01-01

    Background A dual olfactory system, represented by two anatomically distinct but spatially proximate chemosensory epithelia that project to separate areas of the forebrain, is known in several classes of tetrapods. Lungfish are the earliest evolving vertebrates known to have this dual system, comprising a main olfactory and a vomeronasal system (VNO). Lampreys, a group of jawless vertebrates, have a single nasal capsule containing two anatomically distinct epithelia, the main (MOE) and the accessory olfactory epithelia (AOE). We speculated that lamprey AOE projects to specific telencephalic regions as a precursor to the tetrapod vomeronasal system. Results To test this hypothesis, we characterized the neural circuits and molecular profiles of the accessory olfactory epithelium in the sea lamprey (Petromyzon marinus). Neural tract-tracing revealed direct and reciprocal connections with the dorsomedial telencephalic neuropil (DTN) which in turn projects directly to the dorsal pallium and the rostral hypothalamus. High-throughput sequencing demonstrated that the main and the accessory olfactory epithelia have virtually identical profiles of expressed genes. Real time quantitative PCR confirmed expression of representatives of all 3 chemoreceptor gene families identified in the sea lamprey genome. Conclusion Anatomical and molecular evidence shows that the sea lamprey has a primordial accessory olfactory system that may serve a chemosensory function. PMID:23957559

  15. 21 CFR 890.5925 - Traction accessory.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Traction accessory. 890.5925 Section 890.5925 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory....

  16. 21 CFR 890.5925 - Traction accessory.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Traction accessory. 890.5925 Section 890.5925 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory....

  17. 21 CFR 890.5925 - Traction accessory.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Traction accessory. 890.5925 Section 890.5925 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory....

  18. 21 CFR 890.5925 - Traction accessory.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Traction accessory. 890.5925 Section 890.5925 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory....

  19. 21 CFR 890.5925 - Traction accessory.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Traction accessory. 890.5925 Section 890.5925 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5925 Traction accessory....

  20. When Do Item Response Function and Mantel-Haenszel Definitions of Differential Item Functioning Coincide?

    ERIC Educational Resources Information Center

    Zwick, Rebecca

    1990-01-01

    Use of the Mantel-Haenszel procedure as a test for differential item functioning under the Rasch model of item-response theory is examined. Results of the procedure cannot be generalized to the class of items for which item-response functions are monotonic and local independence holds. (TJH)

  1. Control of functional differential equations to target sets in function space

    NASA Technical Reports Server (NTRS)

    Banks, H. T.; Kent, G. A.

    1971-01-01

    Optimal control of systems governed by functional differential equations of retarded and neutral type is considered. Problems with function space initial and terminal manifolds are investigated. Existence of optimal controls, regularity, and bang-bang properties are discussed. Necessary and sufficient conditions are derived, and several solved examples which illustrate the theory are presented.

  2. Quantization of the Sobolev space of half-differentiable functions

    NASA Astrophysics Data System (ADS)

    Sergeev, A. G.

    2016-10-01

    A quantization of the Sobolev space V=H_01/2(S^1, R) of half- differentiable functions on the circle, which is closely connected with string theory, is constructed. The group {QS}(S^1) of quasisymmetric circle homeomorphisms acts on V by reparametrizations, but this action is not smooth. Nevertheless, a quantum infinitesimal action of {QS}(S^1) on V can be defined, which enables one to construct a quantum algebra of observables which is associated with the system (V,{QS}(S^1)). Bibliography: 7 titles.

  3. Differential Effects of Brain Disorders on Structural and Functional Connectivity

    PubMed Central

    Vega-Pons, Sandro; Olivetti, Emanuele; Avesani, Paolo; Dodero, Luca; Gozzi, Alessandro; Bifone, Angelo

    2017-01-01

    Different measures of brain connectivity can be defined based on neuroimaging read-outs, including structural and functional connectivity. Neurological and psychiatric conditions are often associated with abnormal connectivity, but comparing the effects of the disease on different types of connectivity remains a challenge. In this paper, we address the problem of quantifying the relative effects of brain disease on structural and functional connectivity at a group level. Within the framework of a graph representation of connectivity, we introduce a kernel two-sample test as an effective method to assess the difference between the patients and control group. Moreover, we propose a common representation space for structural and functional connectivity networks, and a novel test statistics to quantitatively assess differential effects of the disease on different types of connectivity. We apply this approach to a dataset from BTBR mice, a murine model of Agenesis of the Corpus Callosum (ACC), a congenital disorder characterized by the absence of the main bundle of fibers connecting the two hemispheres. We used normo-callosal mice (B6) as a comparator. The application of the proposed methods to this data-set shows that the two types of connectivity can be successfully used to discriminate between BTBR and B6, meaning that both types of connectivity are affected by ACC. However, our novel test statistics shows that structural connectivity is significantly more affected than functional connectivity, consistent with the idea that functional connectivity has a robust topology that can tolerate substantial alterations in its structural connectivity substrate. PMID:28119556

  4. Differential Effects of Brain Disorders on Structural and Functional Connectivity.

    PubMed

    Vega-Pons, Sandro; Olivetti, Emanuele; Avesani, Paolo; Dodero, Luca; Gozzi, Alessandro; Bifone, Angelo

    2016-01-01

    Different measures of brain connectivity can be defined based on neuroimaging read-outs, including structural and functional connectivity. Neurological and psychiatric conditions are often associated with abnormal connectivity, but comparing the effects of the disease on different types of connectivity remains a challenge. In this paper, we address the problem of quantifying the relative effects of brain disease on structural and functional connectivity at a group level. Within the framework of a graph representation of connectivity, we introduce a kernel two-sample test as an effective method to assess the difference between the patients and control group. Moreover, we propose a common representation space for structural and functional connectivity networks, and a novel test statistics to quantitatively assess differential effects of the disease on different types of connectivity. We apply this approach to a dataset from BTBR mice, a murine model of Agenesis of the Corpus Callosum (ACC), a congenital disorder characterized by the absence of the main bundle of fibers connecting the two hemispheres. We used normo-callosal mice (B6) as a comparator. The application of the proposed methods to this data-set shows that the two types of connectivity can be successfully used to discriminate between BTBR and B6, meaning that both types of connectivity are affected by ACC. However, our novel test statistics shows that structural connectivity is significantly more affected than functional connectivity, consistent with the idea that functional connectivity has a robust topology that can tolerate substantial alterations in its structural connectivity substrate.

  5. Nodal centrality of functional network in the differentiation of schizophrenia

    PubMed Central

    Cheng, Hu; Newman, Sharlene; Goñi, Joaquín; Kent, Jerillyn S.; Howell, Josselyn; Bolbecker, Amanda; Puce, Aina; O’Donnell, Brian F.; Hetrick, William P.

    2015-01-01

    A disturbance in the integration of information during mental processing has been implicated in schizophrenia, possibly due to faulty communication within and between brain regions. Graph theoretic measures allow quantification of functional brain networks. Functional networks are derived from correlations between time courses of brain regions. Group differences between SZ and control groups have been reported for functional network properties, but the potential of such measures to classify individual cases has been little explored. We tested whether the network measure of betweenness centrality could classify persons with schizophrenia and normal controls. Functional networks were constructed for 19 schizophrenic patients and 29 non-psychiatric controls based on resting state functional MRI scans. The betweenness centrality of each node, or fraction of shortest-paths that pass through it, was calculated in order to characterize the centrality of the different regions. The nodes with high betweenness centrality agreed well with hub nodes reported in previous studies of structural and functional networks. Using a linear support vector machine algorithm, the schizophrenia group was differentiated from non-psychiatric controls using the ten nodes with highest betweenness centrality. The classification accuracy was around 80%, and stable against connectivity thresholding. Better performance was achieved when using the ranks as feature space as opposed to the actual values of betweenness centrality. Overall, our findings suggest that changes in functional hubs are associated with schizophrenia, reflecting a variation of the underlying functional network and neuronal communications. In addition, a specific network property, betweenness centrality, can classify persons with SZ with a high level of accuracy. PMID:26299706

  6. Nodal centrality of functional network in the differentiation of schizophrenia.

    PubMed

    Cheng, Hu; Newman, Sharlene; Goñi, Joaquín; Kent, Jerillyn S; Howell, Josselyn; Bolbecker, Amanda; Puce, Aina; O'Donnell, Brian F; Hetrick, William P

    2015-10-01

    A disturbance in the integration of information during mental processing has been implicated in schizophrenia, possibly due to faulty communication within and between brain regions. Graph theoretic measures allow quantification of functional brain networks. Functional networks are derived from correlations between time courses of brain regions. Group differences between SZ and control groups have been reported for functional network properties, but the potential of such measures to classify individual cases has been little explored. We tested whether the network measure of betweenness centrality could classify persons with schizophrenia and normal controls. Functional networks were constructed for 19 schizophrenic patients and 29 non-psychiatric controls based on resting state functional MRI scans. The betweenness centrality of each node, or fraction of shortest-paths that pass through it, was calculated in order to characterize the centrality of the different regions. The nodes with high betweenness centrality agreed well with hub nodes reported in previous studies of structural and functional networks. Using a linear support vector machine algorithm, the schizophrenia group was differentiated from non-psychiatric controls using the ten nodes with the highest betweenness centrality. The classification accuracy was around 80%, and stable against connectivity thresholding. Better performance was achieved when using the ranks as feature space as opposed to the actual values of betweenness centrality. Overall, our findings suggest that changes in functional hubs are associated with schizophrenia, reflecting a variation of the underlying functional network and neuronal communications. In addition, a specific network property, betweenness centrality, can classify persons with SZ with a high level of accuracy.

  7. Normal Variants: Accessory Muscles About the Ankle.

    PubMed

    Cheung, Yvonne

    2017-02-01

    Accessory muscles around the ankle are commonly encountered as incidental findings on cross-sectional imaging. Mostly asymptomatic, accessory muscles sometimes mimic mass lesions. They have been implicated as the cause of tarsal tunnel syndrome, impingement of surrounding structures, and chronic pain. Distinguishing these muscles can be challenging, because some travel along a similar path. This article describes these accessory muscles in detail, including their relationships to the aponeurosis of the lower leg. An imaging algorithm is proposed to aid in identification of these muscles, providing a valuable tool in diagnostic accuracy and subsequent patient management.

  8. Critical roles of co-activation receptor DNAX accessory molecule-1 in natural killer cell immunity

    PubMed Central

    Xiong, Peng; Sang, Hai-Wei; Zhu, Min

    2015-01-01

    Natural killer (NK) cells, which can exert early and powerful anti-tumour and anti-viral responses, are important components of the innate immune system. DNAX accessory molecule-1 (DNAM-1) is an activating receptor molecule expressed on the surface of NK cells. Recent findings suggest that DNAM-1 is a critical regulator of NK cell biology. DNAM-1 is involved in NK cell education and differentiation, and also plays a pivotal role in the development of cancer, viral infections and immune-related diseases. However, tumours and viruses have developed multiple mechanisms to evade the immune system. They are able to impair DNAM-1 activity by targeting the DNAM-1 receptor–ligand system. We have reviewed the roles of DNAM-1, and its biological functions, with respect to NK cell biology and DNAM-1 chimeric antigen receptor-based immunotherapy. PMID:26235210

  9. An Effect Size Measure for Raju's Differential Functioning for Items and Tests

    ERIC Educational Resources Information Center

    Wright, Keith D.; Oshima, T. C.

    2015-01-01

    This study established an effect size measure for differential functioning for items and tests' noncompensatory differential item functioning (NCDIF). The Mantel-Haenszel parameter served as the benchmark for developing NCDIF's effect size measure for reporting moderate and large differential item functioning in test items. The effect size of…

  10. Fibroadenoma of the axillary accessory breast: diagnostic value of dynamic magnetic resonance imaging.

    PubMed

    Sawa, Munehisa; Kawai, Nobuyuki; Sato, Morio; Takeuchi, Taizo; Tamaki, Takeshi; Oura, Shoji

    2010-10-01

    Accessory breast is synonymous with polymastia or supernumerary breast tissue. An accessory breast without a nipple or areola is rare. We report a case of fibroadenoma of an accessory breast with no nipple or areola in a 41-year-old woman who presented with a right axillary mass associated with five small nodules in the normally situated breast. Magnetic resonance imaging (MRI) showed the accessory breast surrounding the tumor. We ignored the presence of the component surrounding the mass and made a preoperative diagnosis of an axillary mass of possible metastases from multiple breast cancers or breast cancer of unknown origin associated with multiple breast fibroadenomas. From a retrospective view, based on the histological results, MRI and dynamic MRI demonstrated a tiny component of breast-like tissue surrounding the axillary mass and an enhancement pattern typical of fibroadenoma for the axillary mass. For the later diagnosis of the axillary mass, the interpretation of whether the component of breast tissue surrounding the axillary mass was present is crucial. If the component exists, a tumor that originated from the accessory breast should be foremost in the differential diagnosis. Dynamic MRI appears to contribute to the diagnosis of fibroadenoma of an accessory breast before biopsy or surgical resection.

  11. Hair follicle nevi and accessory tragi: variable quantity of adipose tissue in connective tissue framework.

    PubMed

    Ban, M; Kamiya, H; Yamada, T; Kitajima, Y

    1997-01-01

    Controversy exists about the histologic differences between hair follicle nevi and accessory tragi. We examined 10 congenital lesions histologically, possible diagnoses of which were hair follicle nevi or accessory tragi. Two specimens out of the 10 had tiny, mature hair follicles surrounded by thick fibrous root sheaths, a few fat cells, and no cartilage. The subcutaneous fat cells of their bases were segmented by a connective tissue framework. They had histologic features of hair follicle nevi. One specimen had cartilage and abundant fat cells with a connective tissue framework in the nodule, as well as a conglomeration of numerous well-differentiated hair follicles. It possessed both elements of a hair follicle nevus and an accessory tragus. Seven specimens had abundant subcutaneous fat and showed a prominent connective tissue framework. These were typical accessory tragi. The present study suggests that the number of fat cells in the nodule or papule differs between these two conditions. All the lesions studied revealed a connective tissue framework in the subcutaneous fat. Histologic features of both hair follicle nevi and accessory tragi can coexist in a single lesion. Hair follicle nevi may represent incomplete accessory tragi with scant fat cells.

  12. Unusual insidious spinal accessory nerve palsy: a case report

    PubMed Central

    2010-01-01

    Introduction Isolated spinal accessory nerve dysfunction has a major detrimental impact on the functional performance of the shoulder girdle, and is a well-documented complication of surgical procedures in the posterior triangle of the neck. To the best of our knowledge, the natural course and the most effective way of handling spontaneous spinal accessory nerve palsy has been described in only a few instances in the literature. Case presentation We report the case of a 36-year-old Caucasian, Greek man with spontaneous unilateral trapezius palsy with an insidious course. To the best of our knowledge, few such cases have been documented in the literature. The unusual clinical presentation and functional performance mismatch with the imaging findings were also observed. Our patient showed a deterioration that was different from the usual course of this pathology, with an early onset of irreversible trapezius muscle dysfunction two months after the first clinical signs started to manifest. A surgical reconstruction was proposed as the most efficient treatment, but our patient declined this. Although he failed to recover fully after conservative treatment for eight months, he regained moderate function and is currently virtually pain-free. Conclusion Clinicians have to be aware that due to anatomical variation and the potential for compensation by the levator scapulae, the clinical consequences of any injury to the spinal accessory nerve may vary. PMID:20507553

  13. 19 CFR 10.456 - Accessories, spare parts or tools.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Accessories, spare parts or tools. 10.456 Section... Trade Agreement Rules of Origin § 10.456 Accessories, spare parts or tools. Accessories, spare parts or tools that form part of the good's standard accessories, spare parts or tools and are delivered with...

  14. Decoding the ecological function of accessory genome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Shiga toxin-producing Escherichia coli O157:H7 primarily resides in cattle asymptomatically, and can be transmitted to humans through food. A study by Lupolova et al applied a machine-learning approach to complex pan-genome information and predicted that only a small subset of bovine isolates have t...

  15. Differential item functioning analysis by applying multiple comparison procedures.

    PubMed

    Eusebi, Paolo; Kreiner, Svend

    2015-01-01

    Analysis within a Rasch measurement framework aims at development of valid and objective test score. One requirement of both validity and objectivity is that items do not show evidence of differential item functioning (DIF). A number of procedures exist for the assessment of DIF including those based on analysis of contingency tables by Mantel-Haenszel tests and partial gamma coefficients. The aim of this paper is to illustrate Multiple Comparison Procedures (MCP) for analysis of DIF relative to a variable defining a very large number of groups, with an unclear ordering with respect to the DIF effect. We propose a single step procedure controlling the false discovery rate for DIF detection. The procedure applies for both dichotomous and polytomous items. In addition to providing evidence against a hypothesis of no DIF, the procedure also provides information on subset of groups that are homogeneous with respect to the DIF effect. A stepwise MCP procedure for this purpose is also introduced.

  16. Oscillation properties of some functional fourth order hyperbolic differential equations

    NASA Astrophysics Data System (ADS)

    Petrova, Z.

    2012-11-01

    In this paper, we apply our recent results for fourth order functional ordinary differential equations and inequalities and obtain sufficient conditions for oscillation of all sufficiently smooth solutions of the following equation ∑ i+j = 2;4ai,j∂i+ju(x,y)/∂xi∂yj+ ∑ i = 1nbi(x,y)u(x-σi,y-τi)+c(x,y,u) = f(x,y), where x>0,y>0,ai,j∈R,σi≥0 and τi ≥ 0 are constants for all the indices. Also, we suppose that n∈N,bi(x,y)∈C(R+2;R+), ∀i = 1-n;c(x,y,u)∈C(R+2,R;R) and f(x,y)∈C(R+2;R). In particular, we establish sufficient conditions for the distribution of zeros this equation.

  17. Suppression subtractive hybridization analysis reveals expression of conserved and novel genes in male accessory glands of the ant Leptothorax gredleri

    PubMed Central

    2010-01-01

    Background During mating, insect males eject accessory gland proteins (Acps) into the female genital tract. These substances are known to affect female post-mating behavior and physiology. In addition, they may harm the female, e.g., in reducing its lifespan. This is interpreted as a consequence of sexual antagonistic co-evolution. Whereas sexual conflict abounds in non-social species, the peculiar life history of social insects (ants, bees, wasps) with lifelong pair-bonding and no re-mating aligns the reproductive interests of the sexes. Harming the female during mating would negatively affect male fitness and sexual antagonism is therefore not expected. Indeed, mating appears to increase female longevity in at least one ant species. Acps are presumed to play a role in this phenomenon, but the underlying mechanisms are unknown. In this study, we investigated genes, which are preferentially expressed in male accessory glands of the ant Leptothorax gredleri, to determine which proteins might be transferred in the seminal fluid. Results By a suppression subtractive hybridization protocol we obtained 20 unique sequences (USs). Twelve had mutual best matches with genes predicted for Apis mellifera and Nasonia vitripennis. Functional information (Gene Ontology) was available only for seven of these, including intracellular signaling, energy-dependent transport and metabolic enzyme activities. The remaining eight USs did not match sequences from other species. Six genes were further analyzed by quantitative RT-PCR in three life cycle stages of male ants. A gene with carboxy-lyase activity and one of unpredicted function were significantly overexpressed in accessory glands of sexually mature males. Conclusions Our study is the first one to investigate differential gene expression in ants in a context related to mating. Our findings indicate that male accessory glands of L. gredleri express a series of genes that are unique to this species, possibly representing novel

  18. Manual therapy of the mandibular accessory ligaments for the management of temporomandibular joint disorders.

    PubMed

    Cuccia, Antonino Marco; Caradonna, Carola; Caradonna, Domenico

    2011-02-01

    Temporomandibular joint disorders are characterized by chronic or acute musculoskeletal or myofascial pain with dysfunction of the masticatory system. Treatment modalities include occlusal splints, patient education, activity modification, muscle and joint exercises, myofascial therapy, acupuncture, and manipulative therapy. In the physiology of the temporomandibular joint, accessory ligaments limit the movement of the mandible. A thorough knowledge of the anatomy of accessory ligaments is necessary for good clinical management of temporomandibular joint disorders. Although general principles regarding the anatomy of the ligaments are relatively clear, very little substantiated information on the dimension, orientation, and function of the ligaments has been published, to the authors' knowledge. The authors review the literature concerning the accessory ligaments of the temporomandibular joint and describe treatment options, including manual techniques for mobilizing the accessory ligaments.

  19. Differential association between chronic cannabis use and brain function deficits.

    PubMed

    Soueif, M I

    1976-01-01

    To summarize, 12 objective tests that generated 16 test variables were administered to 850 male regular cannabis users and 839 nonusers. The tests were designed to assess various modalities, including speed of psychomotor performance, distance estimation, time estimation, immediate memory, and visuomotor coordination. Most of the test variables differentiated significantly between consumers and controls. At the same time, a significant second-order interaction emerged in most cases. This interaction meant that, under certain conditions that relate to the two dimensions "literacy-illiteracy" and/or "urbanism-ruralism," the superiority of controls over cannabis users became impressive, whereas under other conditions it almost disappeared. To account for this complex pattern of results, a working hypothesis was presented to the effect that "other conditions being equal, the lower the nondrug level of proficiency on tests of cognitive and psychomotor performance the smaller the size of function deficit associated with drug usage." For an empirical examination of the hypothesis, six predictions were formulated. Three predictions defined specific relationships between level of performance, on one hand, and each of three organismic variables, on the other: literacy, urbanism, and age. The remaining predictions delineated relationships to be expected between size of function deficit and the three organismic variables. All our predictions were confirmed, showing less function impairment to be contingent with cannabis usage among the illiterates, rurals, and older subjects. Level of cortical arousal was suggested as the central process associated with the three organismic variables. Because the version of our working hypothesis was formulated with reference to chronic material, the possibility of a transposition of the paradign to research on the acute effects of the drug was discussed. The suggestion was made that our working hypothesis, in either version, is capable of

  20. Differential Assemblage of Functional Units in Paddy Soil Microbiomes

    PubMed Central

    Kim, Yongkyu; Liesack, Werner

    2015-01-01

    Flooded rice fields are not only a global food source but also a major biogenic source of atmospheric methane. Using metatranscriptomics, we comparatively explored structural and functional succession of paddy soil microbiomes in the oxic surface layer and anoxic bulk soil. Cyanobacteria, Fungi, Xanthomonadales, Myxococcales, and Methylococcales were the most abundant and metabolically active groups in the oxic zone, while Clostridia, Actinobacteria, Geobacter, Anaeromyxobacter, Anaerolineae, and methanogenic archaea dominated the anoxic zone. The protein synthesis potential of these groups was about 75% and 50% of the entire community capacity, respectively. Their structure-function relationships in microbiome succession were revealed by classifying the protein-coding transcripts into core, non-core, and taxon-specific transcripts based on homologous gene distribution. The differential expression of core transcripts between the two microbiomes indicated that structural succession is primarily governed by the cellular ability to adapt to the given oxygen condition, involving oxidative stress, nitrogen/phosphorus metabolism, and fermentation. By contrast, the non-core transcripts were expressed from genes involved in the metabolism of various carbon sources. Among those, taxon-specific transcripts revealed highly specialized roles of the dominant groups in community-wide functioning. For instance, taxon-specific transcripts involved in photosynthesis and methane oxidation were a characteristic of the oxic zone, while those related to methane production and aromatic compound degradation were specific to the anoxic zone. Degradation of organic matters, antibiotics resistance, and secondary metabolite production were detected to be expressed in both the oxic and anoxic zones, but by different taxonomic groups. Cross-feeding of methanol between members of the Methylococcales and Xanthomonadales was suggested by the observation that in the oxic zone, they both

  1. Defining a Model for Mitochondrial Function in mESC Differentiation

    EPA Science Inventory

    Defining a Model for Mitochondrial Function in mESC DifferentiationDefining a Model for Mitochondrial Function in mESC Differentiation Differentiating embryonic stem cells (ESCs) undergo mitochondrial maturation leading to a switch from a system dependent upon glycolysis to a re...

  2. Multiscale functions, scale dynamics, and applications to partial differential equations

    NASA Astrophysics Data System (ADS)

    Cresson, Jacky; Pierret, Frédéric

    2016-05-01

    Modeling phenomena from experimental data always begins with a choice of hypothesis on the observed dynamics such as determinism, randomness, and differentiability. Depending on these choices, different behaviors can be observed. The natural question associated to the modeling problem is the following: "With a finite set of data concerning a phenomenon, can we recover its underlying nature? From this problem, we introduce in this paper the definition of multi-scale functions, scale calculus, and scale dynamics based on the time scale calculus [see Bohner, M. and Peterson, A., Dynamic Equations on Time Scales: An Introduction with Applications (Springer Science & Business Media, 2001)] which is used to introduce the notion of scale equations. These definitions will be illustrated on the multi-scale Okamoto's functions. Scale equations are analysed using scale regimes and the notion of asymptotic model for a scale equation under a particular scale regime. The introduced formalism explains why a single scale equation can produce distinct continuous models even if the equation is scale invariant. Typical examples of such equations are given by the scale Euler-Lagrange equation. We illustrate our results using the scale Newton's equation which gives rise to a non-linear diffusion equation or a non-linear Schrödinger equation as asymptotic continuous models depending on the particular fractional scale regime which is considered.

  3. Rare association in a female DSD case of phallus, accessory phallic urethra, perineal lipoma and anterior ectopic anus.

    PubMed

    Mahalik, Santosh Kumar; Mahajan, Jai Kumar; Sodhi, Kushaljit Singh; Garge, Saurabh; Vaiphei, Kim; Rao, Kattragadda L

    2013-02-01

    Disorders of sex differentiation (DSD) are a heterogeneous and broad spectrum group of diseases with a varied appearance. Presence of an accessory phallus with a phallic urethra in association with a normal vagina in a female is an extremely uncommon anomaly. We present a rare case of a genotypically female child with a normal urethra and vagina in association with a phallus, accessory phallic urethra, perineal lipoma and anterior ectopic anus.

  4. 21 CFR 878.4950 - Manual operating table and accessories and manual operating chair and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Manual operating table and accessories and manual operating chair and accessories. 878.4950 Section 878.4950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY...

  5. 21 CFR 878.4960 - Operating tables and accessories and operating chairs and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Operating tables and accessories and operating chairs and accessories. 878.4960 Section 878.4960 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES...

  6. 21 CFR 878.4960 - Operating tables and accessories and operating chairs and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Operating tables and accessories and operating chairs and accessories. 878.4960 Section 878.4960 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES...

  7. 21 CFR 878.4950 - Manual operating table and accessories and manual operating chair and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Manual operating table and accessories and manual operating chair and accessories. 878.4950 Section 878.4950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY...

  8. 21 CFR 878.4960 - Operating tables and accessories and operating chairs and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Operating tables and accessories and operating chairs and accessories. 878.4960 Section 878.4960 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES...

  9. 21 CFR 878.4950 - Manual operating table and accessories and manual operating chair and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Manual operating table and accessories and manual operating chair and accessories. 878.4950 Section 878.4950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY...

  10. 21 CFR 878.4950 - Manual operating table and accessories and manual operating chair and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Manual operating table and accessories and manual operating chair and accessories. 878.4950 Section 878.4950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY...

  11. 21 CFR 878.4950 - Manual operating table and accessories and manual operating chair and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Manual operating table and accessories and manual operating chair and accessories. 878.4950 Section 878.4950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY...

  12. 21 CFR 878.4960 - Operating tables and accessories and operating chairs and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Operating tables and accessories and operating chairs and accessories. 878.4960 Section 878.4960 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES...

  13. 21 CFR 878.4960 - Operating tables and accessories and operating chairs and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Operating tables and accessories and operating chairs and accessories. 878.4960 Section 878.4960 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES...

  14. Building the blocks of executive functioning: differentiating early developing processes contributing to executive functioning skills.

    PubMed

    Mandell, Dorothy J; Ward, Sarah E

    2011-12-01

    The neural processes that underlie executive function begin to develop in infancy. However, it is unclear how the behavior manifested by these processes are related or if they can be differentiated early in development. This study seeks to examine early emerging executive functioning skills in monkeys (Macaca fascicularis) by using an error analysis approach where traditional measures of the tasks, as well as identification of major error patterns are related. Results show that during the infancy and early juvenile period, two processes that help support set-maintenance could be differentiated: modulation of responses to novelty and persistence despite negative feedback. The results suggest that these two aspects of set-maintenance were largely independent. Modulation of responses to novelty was most prominent in the infancy and early juvenile period. The ability to persist with a response set despite negative feedback emerged in the early juvenile period and was related to task performance until the end of the study.

  15. Progress in the clinical imaging research of bone diseases on ankle and foot sesamoid bones and accessory ossicles.

    PubMed

    Li, Xiaozhong; Shi, Lenian; Liu, Taiyun; Wang, Lin

    2012-08-01

    Sesamoid bones and accessory ossicles are research focuses of foot and ankle surgery. Pains of the foot and ankle are related to sesamoid bones and accessory ossicles. The specific anatomical and functional relationship of sesamoid bones and accessory ossicles can cause such bone diseases as the dislocation of sesamoid bones and accessory bones, infection, inflammation and necrosis of sesamoid bones, cartilage softening, tenosynovitis of sesamoid bones and the sesamoid bone syndrome. However, these bone diseases are often misdiagnosed or mistreated. In patients with trauma history, relevant diseases of sesamoid bones and accessory ossicles as above mentioned are highly probable to be misdiagnosed as avulsion fractures. In such cases, radiographic findings may provide a basis for clinical diagnosis.

  16. Accessory spleen in the pelvis: A case report

    PubMed Central

    Taskin, Mine Islimye; Baser, Banu Guleç; Adali, Ertan; Bulbul, Erdoğan; Uzgoren, Engin

    2015-01-01

    Introduction Accessory Spleen (AS) is a very rare entity and usually near the spleen’s hilum and in the tail of the pancreas. Pelvis reported as an atypical and a rare localization. AS may be formed during embryonic life, they rise from the left side of the dorsal mesogastrium as a result of imperfect fusion of separate splenic masses. Presentation of case We report a case of an AS presenting as an left adnexal mass in a middle-aged woman. Transvaginal ultrasonography and magnetic resonance imaging (MRI) revealed a left adnexial mass. Laparatomy was performed, and histological examination revealed that resected mass was splenic tissue. Discussion An AS is an incidental finding of no clinical significance in most patients. AS are generally determined during radiological investigations or during open or laparoscopic surgeries. When, the AS settle in the adnexal area; the differential diagnosis could include the causes of adnexal masses like enlarged lymph nodes, subserous fibroid, ovarian tumors, organized hematoma, tuboovarian abscess. Conclusion Althought pelvic accessory spleen is a rare condition, should be considered in the differential diagnosis of adnexal masses. PMID:25985297

  17. Smallpox vaccination techniques. 2. Accessories and aftercare.

    PubMed

    Baxby, Derrick

    2003-03-28

    The various accessories used for smallpox vaccination are surveyed. These included modified vaccination instruments and various other items which facilitated the procedure, containers for preservation and transport of vaccine, sterilising equipment, aids to interpretation and recording, and a variety of skin preparations and dressings. Three phases can be discerned in the development and use of such items and procedures. Initially, in the pre-bacteriological era, there was little need for accessory equipment apart from the means of preserving and transporting vaccine. Later, particularly by the end of the 19th century, the importance of aseptic and antiseptic procedures was realised, use was made of more traumatic vaccination techniques and glass capillaries became the standard method for preservation and transport. All this led to the increasing availability of a wide range of accessories, particularly of skin preparations and dressings. Finally, from about 1930, it was appreciated that skin preparation and dressings were often unnecessary, and could be counter-productive. So, although accessories for this were still available their use was very much reduced. In some respects the use of accessories during this last phase, based on scientific analysis was a return to the earliest, 'pre-scientific', era.

  18. Functional differentiation of cytotoxic cancer drugs and targeted cancer therapeutics.

    PubMed

    Winkler, Gian C; Barle, Ester Lovsin; Galati, Giuseppe; Kluwe, William M

    2014-10-01

    There is no nationally or internationally binding definition of the term "cytotoxic drug" although this term is used in a variety of regulations for pharmaceutical development and manufacturing of drugs as well as in regulations for protecting medical personnel from occupational exposure in pharmacy, hospital, and other healthcare settings. The term "cytotoxic drug" is frequently used as a synonym for any and all oncology or antineoplastic drugs. Pharmaceutical companies generate and receive requests for assessments of the potential hazards of drugs regularly - including cytotoxicity. This publication is intended to provide functional definitions that help to differentiate between generically-cytotoxic cancer drugs of significant risk to normal human tissues, and targeted cancer therapeutics that pose much lesser risks. Together with specific assessments, it provides comprehensible guidance on how to assess the relevant properties of cancer drugs, and how targeted therapeutics discriminate between cancer and normal cells. The position of several regulatory agencies in the long-term is clearly to regulate all drugs regardless of classification, according to scientific risk based data. Despite ongoing discussions on how to replace the term "cytotoxic drugs" in current regulations, it is expected that its use will continue for the near future.

  19. Phosphoinositides differentially regulate alpha-actinin flexibility and function.

    PubMed

    Corgan, Anne Marie; Singleton, CoreyAyne; Santoso, Cynthia B; Greenwood, Jeffrey A

    2004-03-15

    Alpha-actinin is a cell-adhesion and cytoskeletal protein that bundles actin microfilaments and links these filaments directly to integrin-adhesion receptors. Phosphoinositides bind to and regulate the interaction of a-actinin with actin filaments and integrin receptors. In the present study, we demonstrate that PtdIns(3,4,5)P3 inhibits and disrupts a-actinin-bundling activity, whereas PtdIns(4,5)P2 can only inhibit activity. In addition, a protease-sensitivity assay was developed to examine the flexibility of the linker region between the actin-binding domain and the spectrin repeats of a-actinin. Both phosphoinositides influenced the extent of proteolysis and the cleavage sites. PtdIns(4,5)P2 binding decreased the proteolysis of a-actinin, suggesting a role in stabilizing the structure of the protein. In contrast, PtdIns(3,4,5)P3 binding enhanced a-actinin proteolysis, indicating an increase in the flexibility of the protein. Furthermore, phosphoinositide binding influenced the proteolysis of the N- and C-terminal domains of a-actinin, indicating regulation of structure within both domains. These results support the hypothesis that PtdIns(4,5)P2 and PtdIns(3,4,5)P3 differentially regulate a-actinin function by modulating the structure and flexibility of the protein.

  20. Improvement in Detection of Differential Item Functioning Using a Mixture Item Response Theory Model

    ERIC Educational Resources Information Center

    Maij-de Meij, Annette M.; Kelderman, Henk; van der Flier, Henk

    2010-01-01

    Usually, methods for detection of differential item functioning (DIF) compare the functioning of items across manifest groups. However, the manifest groups with respect to which the items function differentially may not necessarily coincide with the true source of the bias. It is expected that DIF detection under a model that includes a latent DIF…

  1. Controlled Speed Accessory Drive demonstration program

    NASA Technical Reports Server (NTRS)

    Hoehn, F. W.

    1981-01-01

    A Controlled Speed Accessory Drive System was examined in an effort to improve the fuel economy of passenger cars. Concept feasibility and the performance of a typical system during actual road driving conditions were demonstrated. The CSAD system is described as a mechanical device which limits engine accessory speeds, thereby reducing parasitic horsepower losses and improving overall vehicle fuel economy. Fuel consumption data were compiled for fleets of GSA vehicles. Various motor pool locations were selected, each representing different climatic conditions. On the basis of a total accumulated fleet usage of nearly three million miles, an overall fuel economy improvement of 6 percent to 7 percent was demonstrated. Coincident chassis dynamometer tests were accomplished on selected vehicles to establish the effect of different accessory drive systems on exhaust emissions, and to evaluate the magnitude of the mileage benefits which could be derived.

  2. An unusual case of retroperitoneal accessory spleen with vascular supply directly from the aorta.

    PubMed

    Souparis, A; Papaziogas, B; Alexandrakis, A; Koutelidakis, J; Paraskevas, G; Papaziogas, T

    2002-08-01

    We report on a case of a retroperitoneal accessory spleen with vascular supply directly from the aorta. A 47-year old woman presented with a six-month history of epigastric pain, intermittent nausea and vomiting. The CT scan of the abdomen revealed the presence of a retroperitoneal tumor between the spleen, left kidney and pancreas. The MR-tomography confirmed the presence of a solid tumor, with vascular supply directly from the aorta. The exploratory laparotomy showed the presence of a well-shaped accessory spleen, which was confirmed by the histological examination of the specimen. The surgeon should be aware of the possible existence of accessory spleens for the differential diagnosis of retroperitoneal tumors.

  3. Structure and diversity in mammalian accessory olfactory bulb.

    PubMed

    Meisami, E; Bhatnagar, K P

    1998-12-15

    The accessory olfactory bulb (AOB) is the first neural integrative center for the olfactory-like vomeronasal sensory system. In this article, we first briefly present an overview of vomeronasal system organization and review the history of the discovery of mammalian AOB. Next, we briefly review the evolution of the vomeronasal system in vertebrates, in particular the reptiles. Following these introductory aspects, the structure of the rodent AOB, as typical of the well-developed mammalian AOB, is presented, detailing laminar organization and cell types as well as aspects of the homology with the main olfactory bulb. Then, the evolutionary origin and diversity of the AOB in mammalian orders and species is discussed, describing structural, phylogenetic, and species-specific variation in the AOB location, shape, and size and morphologic differentiation and development. The AOB is believed to be absent in fishes but present in terrestrial tetrapods including amphibians; among the reptiles AOB is absent in crocodiles, present in turtles, snakes, and some lizards where it may be as large or larger than the main bulb. The AOB is absent in bird and in the aquatic mammals (whales, porpoises, manatees). Among other mammals, AOB is present in the monotremes and marsupials, edentates, and in the majority of the placental mammals like carnivores, herbivores, as well as rodents and lagomorphs. Most bat species do not have an AOB and among those where one is found, it shows marked variation in size and morphologic development. Among insectivores and primates, AOB shows marked variation in occurrence, size, and morphologic development. It is small in shrews and moles, large in hedgehogs and prosimians; AOB continues to persist in New World monkeys but is not found in the adults of the higher primates such as the Old World monkeys, apes, and humans. In many species where AOB is absent in the adult, it often develops in the embryo and fetus but regresses in later stages of

  4. Post-splenectomy intrapancreatic accessory spleen mimicking endocrine tumor of the pancreas

    PubMed Central

    Zhu, Hong-xu; Lou, Wen-hui; Kuang, Tian-tao; Wang, Dan-song

    2014-01-01

    INTRODUCTION Intrapancreatic accessory spleen is an uncommon congenital abnormality of the spleen with no indication for surgical intervention. Among the few cases reported, IPAS coexisted with a normal spleen. We here report the first case of IPAS arising a couple years after splenectomy with the appearance of an endocrine tumor of the pancreas. PRESENTATION OF CASE A 62-year-old female presented with a one-week history of left upper quadrant discomfort. She had splenectomy for the treatment of hypersplenism caused by cirrhotic portal hypertension two years before this admission. Her physical examination was unremarkable and laboratory data was within the normal range. Both the ultrasonography and magnetic resonance image revealed a small oval-shaped mass in the tail of her pancreas with the diameter 2 cm or less. A distal pancreatectomy was performed for the suspection of malignant neuroendocrine tumor of the pancreas. An intrapancreatic accessory spleen was confirmed by the pathologic examination. DISCUSSION Intrapancreatic accessory spleen is one kind of congenital ectopic spleen without indication for operative intervention. We present the case to support that intrapancreatic accessory spleen may enlarge through a compensatory mechanism, and raise the awareness of this intrapacreatic entity to avoid unnecessary surgical operation. CONCLUSION IPAS should be highly considered as a differential diagnosis while the lesion is no more than 2.5 cm in diameter and/or other accessory spleens show around the splenic hilum. PMID:25437661

  5. 46 CFR 169.671 - Accessories.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Accessories. 169.671 Section 169.671 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Electrical Installations Operating at Potentials of Less Than 50 Volts on Vessels of Less Than...

  6. 46 CFR 169.671 - Accessories.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Accessories. 169.671 Section 169.671 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Electrical Installations Operating at Potentials of Less Than 50 Volts on Vessels of Less Than...

  7. 46 CFR 169.671 - Accessories.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Accessories. 169.671 Section 169.671 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Electrical Installations Operating at Potentials of Less Than 50 Volts on Vessels of Less Than...

  8. 46 CFR 169.671 - Accessories.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Accessories. 169.671 Section 169.671 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Electrical Installations Operating at Potentials of Less Than 50 Volts on Vessels of Less Than...

  9. 14 CFR 23.1163 - Powerplant accessories.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...) Have torque limiting means on all accessory drives in order to prevent the torque limits established... approved as part of the powerplant driving the gearbox must— (1) Have torque limiting means to prevent the torque limits established for the affected drive from being exceeded; (2) Use the provisions on...

  10. 14 CFR 23.1163 - Powerplant accessories.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) Have torque limiting means on all accessory drives in order to prevent the torque limits established... approved as part of the powerplant driving the gearbox must— (1) Have torque limiting means to prevent the torque limits established for the affected drive from being exceeded; (2) Use the provisions on...

  11. 14 CFR 23.1163 - Powerplant accessories.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...) Have torque limiting means on all accessory drives in order to prevent the torque limits established... approved as part of the powerplant driving the gearbox must— (1) Have torque limiting means to prevent the torque limits established for the affected drive from being exceeded; (2) Use the provisions on...

  12. 14 CFR 23.1163 - Powerplant accessories.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...) Have torque limiting means on all accessory drives in order to prevent the torque limits established... approved as part of the powerplant driving the gearbox must— (1) Have torque limiting means to prevent the torque limits established for the affected drive from being exceeded; (2) Use the provisions on...

  13. 14 CFR 23.1163 - Powerplant accessories.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...) Have torque limiting means on all accessory drives in order to prevent the torque limits established... approved as part of the powerplant driving the gearbox must— (1) Have torque limiting means to prevent the torque limits established for the affected drive from being exceeded; (2) Use the provisions on...

  14. 21 CFR 890.3910 - Wheelchair accessory.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Wheelchair accessory. 890.3910 Section 890.3910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910...

  15. 21 CFR 890.3910 - Wheelchair accessory.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Wheelchair accessory. 890.3910 Section 890.3910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910...

  16. 21 CFR 890.3910 - Wheelchair accessory.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Wheelchair accessory. 890.3910 Section 890.3910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910...

  17. 21 CFR 890.3910 - Wheelchair accessory.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wheelchair accessory. 890.3910 Section 890.3910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910...

  18. 21 CFR 890.3910 - Wheelchair accessory.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Wheelchair accessory. 890.3910 Section 890.3910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3910...

  19. Electronic Position Sensor for Power Operated Accessory

    DOEpatents

    Haag, Ronald H.; Chia, Michael I.

    2005-05-31

    An electronic position sensor for use with a power operated vehicle accessory, such as a power liftgate. The position sensor includes an elongated resistive circuit that is mounted such that it is stationary and extends along the path of a track portion of the power operated accessory. The position sensor further includes a contact nub mounted to a link member that moves within the track portion such that the contact nub is slidingly biased against the elongated circuit. As the link member moves under the force of a motor-driven output gear, the contact nub slides along the surface of the resistive circuit, thereby affecting the overall resistance of the circuit. The position sensor uses the overall resistance to provide an electronic position signal to an ECU, wherein the signal is indicative of the absolute position of the power operated accessory. Accordingly, the electronic position sensor is capable of providing an electronic signal that enables the ECU to track the absolute position of the power operated accessory.

  20. Home Economics Careers in Apparel and Accessories.

    ERIC Educational Resources Information Center

    Texas Education Agency, Austin. Dept. of Occupational Education and Technology.

    This course of study on careers in apparel and accessories is one of a series on home economics careers designed to assist teacher-coordinators in Texas in promotion and/or teaching home economics cooperative education programs. The course of study consists of (1) an overview and job description, (2) a job analysis, (3) a course outline, (4)…

  1. 46 CFR 169.671 - Accessories.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Accessories. 169.671 Section 169.671 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and Electrical Electrical Installations Operating at Potentials of Less Than 50 Volts on Vessels of Less Than...

  2. Estimation of Delays and Other Parameters in Nonlinear Functional Differential Equations.

    DTIC Science & Technology

    1981-12-01

    FSTIMATION OF DELAYS AND OTHER PARAMETERS IN NONLINEAR FUNCTIONAL DIFFERENTIAL EQUATIONS by K. T. Banks and P. L. Daniel December 1981 LCDS Report #82...ESTIMATION OF DELAYS AND OTHER PARAMETERS IN NONLINEAR FUNCTIONAL DIFFERENTIAL EQUATIONS H. T. Banks and P. L. Daniel ABSTRACT We discuss a spline...based approximation scheme for nonlinear nonautonomous delay differential equations . Convergence results (using dissipative type estimates on the

  3. 21 CFR 878.4700 - Surgical microscope and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Surgical microscope and accessories. 878.4700 Section 878.4700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... microscope and accessories. (a) Identification. A surgical microscope and accessories is an AC-powered...

  4. 21 CFR 878.4700 - Surgical microscope and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Surgical microscope and accessories. 878.4700 Section 878.4700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... microscope and accessories. (a) Identification. A surgical microscope and accessories is an AC-powered...

  5. 21 CFR 878.4700 - Surgical microscope and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Surgical microscope and accessories. 878.4700 Section 878.4700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... microscope and accessories. (a) Identification. A surgical microscope and accessories is an AC-powered...

  6. 21 CFR 878.4700 - Surgical microscope and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Surgical microscope and accessories. 878.4700 Section 878.4700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... microscope and accessories. (a) Identification. A surgical microscope and accessories is an AC-powered...

  7. 21 CFR 876.5540 - Blood access device and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Blood access device and accessories. 876.5540... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5540 Blood access device and accessories. (a) Identification. A blood access device and accessories is a device intended...

  8. 21 CFR 876.5540 - Blood access device and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Blood access device and accessories. 876.5540... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5540 Blood access device and accessories. (a) Identification. A blood access device and accessories is a device intended...

  9. 21 CFR 876.5540 - Blood access device and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Blood access device and accessories. 876.5540... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5540 Blood access device and accessories. (a) Identification. A blood access device and accessories is a device intended...

  10. 21 CFR 876.5540 - Blood access device and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Blood access device and accessories. 876.5540... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5540 Blood access device and accessories. (a) Identification. A blood access device and accessories is a device intended...

  11. 14 CFR 25.1192 - Engine accessory section diaphragm.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Engine accessory section diaphragm. 25.1192....1192 Engine accessory section diaphragm. For reciprocating engines, the engine power section and all portions of the exhaust system must be isolated from the engine accessory compartment by a diaphragm...

  12. 19 CFR 10.600 - Accessories, spare parts, or tools.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Accessories, spare parts, or tools. 10.600 Section... tools. (a) General. Accessories, spare parts, or tools that are delivered with a good and that form part of the good's standard accessories, spare parts, or tools will be treated as originating goods if...

  13. 19 CFR 10.537 - Accessories, spare parts, or tools.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Accessories, spare parts, or tools. 10.537 Section... Free Trade Agreement Rules of Origin § 10.537 Accessories, spare parts, or tools. Accessories, spare parts, or tools that are delivered with a good and that form part of the good's standard...

  14. 21 CFR 872.4120 - Bone cutting instrument and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Bone cutting instrument and accessories. 872.4120... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4120 Bone cutting instrument and accessories. (a) Identification. A bone cutting instrument and accessories is a metal device intended for...

  15. 21 CFR 872.4120 - Bone cutting instrument and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Bone cutting instrument and accessories. 872.4120... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4120 Bone cutting instrument and accessories. (a) Identification. A bone cutting instrument and accessories is a metal device intended for...

  16. 21 CFR 872.4120 - Bone cutting instrument and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bone cutting instrument and accessories. 872.4120... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4120 Bone cutting instrument and accessories. (a) Identification. A bone cutting instrument and accessories is a metal device intended for...

  17. 21 CFR 872.4120 - Bone cutting instrument and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Bone cutting instrument and accessories. 872.4120... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4120 Bone cutting instrument and accessories. (a) Identification. A bone cutting instrument and accessories is a metal device intended for...

  18. 21 CFR 872.4120 - Bone cutting instrument and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Bone cutting instrument and accessories. 872.4120... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4120 Bone cutting instrument and accessories. (a) Identification. A bone cutting instrument and accessories is a metal device intended for...

  19. 21 CFR 878.4700 - Surgical microscope and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Surgical microscope and accessories. 878.4700 Section 878.4700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... microscope and accessories. (a) Identification. A surgical microscope and accessories is an AC-powered...

  20. 14 CFR 25.1192 - Engine accessory section diaphragm.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine accessory section diaphragm. 25.1192....1192 Engine accessory section diaphragm. For reciprocating engines, the engine power section and all portions of the exhaust system must be isolated from the engine accessory compartment by a diaphragm...

  1. 14 CFR 25.1192 - Engine accessory section diaphragm.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Engine accessory section diaphragm. 25.1192....1192 Engine accessory section diaphragm. For reciprocating engines, the engine power section and all portions of the exhaust system must be isolated from the engine accessory compartment by a diaphragm...

  2. 21 CFR 868.5860 - Pressure tubing and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Pressure tubing and accessories. 868.5860 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5860 Pressure tubing and accessories. (a) Identification. Pressure tubing and accessories are flexible or rigid devices intended...

  3. 21 CFR 868.5860 - Pressure tubing and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Pressure tubing and accessories. 868.5860 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5860 Pressure tubing and accessories. (a) Identification. Pressure tubing and accessories are flexible or rigid devices intended...

  4. 21 CFR 868.5860 - Pressure tubing and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pressure tubing and accessories. 868.5860 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5860 Pressure tubing and accessories. (a) Identification. Pressure tubing and accessories are flexible or rigid devices intended...

  5. 21 CFR 868.5860 - Pressure tubing and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Pressure tubing and accessories. 868.5860 Section... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5860 Pressure tubing and accessories. (a) Identification. Pressure tubing and accessories are flexible or rigid devices intended...

  6. 21 CFR 876.5540 - Blood access device and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Blood access device and accessories. 876.5540... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5540 Blood access device and accessories. (a) Identification. A blood access device and accessories is a device intended...

  7. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...

  8. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...

  9. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...

  10. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...

  11. 21 CFR 872.6300 - Rubber dam and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Rubber dam and accessories. 872.6300 Section 872...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in...

  12. 21 CFR 872.3980 - Endosseous dental implant accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Endosseous dental implant accessories. 872.3980... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3980 Endosseous dental implant accessories. (a) Identification. Endosseous dental implant accessories are manually powered devices...

  13. 21 CFR 878.3925 - Plastic surgery kit and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Plastic surgery kit and accessories. 878.3925... (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3925 Plastic surgery kit and accessories. (a) Identification. A plastic surgery kit and accessories is a device intended...

  14. 21 CFR 878.3925 - Plastic surgery kit and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Plastic surgery kit and accessories. 878.3925... (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3925 Plastic surgery kit and accessories. (a) Identification. A plastic surgery kit and accessories is a device intended...

  15. 21 CFR 878.3925 - Plastic surgery kit and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Plastic surgery kit and accessories. 878.3925... (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3925 Plastic surgery kit and accessories. (a) Identification. A plastic surgery kit and accessories is a device intended...

  16. 21 CFR 878.3925 - Plastic surgery kit and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Plastic surgery kit and accessories. 878.3925... (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3925 Plastic surgery kit and accessories. (a) Identification. A plastic surgery kit and accessories is a device intended...

  17. 21 CFR 878.3925 - Plastic surgery kit and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Plastic surgery kit and accessories. 878.3925... (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3925 Plastic surgery kit and accessories. (a) Identification. A plastic surgery kit and accessories is a device intended...

  18. 21 CFR 876.5250 - Urine collector and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Urine collector and accessories. 876.5250 Section... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5250 Urine collector and accessories. (a) Identification. A urine collector and accessories is a device intended to...

  19. 21 CFR 876.5250 - Urine collector and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Urine collector and accessories. 876.5250 Section... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5250 Urine collector and accessories. (a) Identification. A urine collector and accessories is a device intended to...

  20. 21 CFR 876.5250 - Urine collector and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Urine collector and accessories. 876.5250 Section... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5250 Urine collector and accessories. (a) Identification. A urine collector and accessories is a device intended to...

  1. 21 CFR 876.5250 - Urine collector and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Urine collector and accessories. 876.5250 Section... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5250 Urine collector and accessories. (a) Identification. A urine collector and accessories is a device intended to...

  2. 21 CFR 876.5250 - Urine collector and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Urine collector and accessories. 876.5250 Section... (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5250 Urine collector and accessories. (a) Identification. A urine collector and accessories is a device intended to...

  3. 21 CFR 884.6120 - Assisted reproduction accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Assisted reproduction accessories. 884.6120... (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6120 Assisted reproduction accessories. (a) Identification. Assisted reproduction accessories are a group...

  4. 21 CFR 884.6120 - Assisted reproduction accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Assisted reproduction accessories. 884.6120... (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6120 Assisted reproduction accessories. (a) Identification. Assisted reproduction accessories are a group...

  5. 21 CFR 884.6120 - Assisted reproduction accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Assisted reproduction accessories. 884.6120... (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6120 Assisted reproduction accessories. (a) Identification. Assisted reproduction accessories are a group...

  6. 21 CFR 884.6120 - Assisted reproduction accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Assisted reproduction accessories. 884.6120... (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6120 Assisted reproduction accessories. (a) Identification. Assisted reproduction accessories are a group...

  7. 21 CFR 884.6120 - Assisted reproduction accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Assisted reproduction accessories. 884.6120... (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Assisted Reproduction Devices § 884.6120 Assisted reproduction accessories. (a) Identification. Assisted reproduction accessories are a group...

  8. 21 CFR 876.5980 - Gastrointestinal tube and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Gastrointestinal tube and accessories. 876.5980... tube and accessories. (a) Identification. A gastrointestinal tube and accessories is a device that..., gastrointestinal string and tubes to locate internal bleeding, double lumen tube for intestinal decompression...

  9. 21 CFR 876.5980 - Gastrointestinal tube and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Gastrointestinal tube and accessories. 876.5980... tube and accessories. (a) Identification. A gastrointestinal tube and accessories is a device that..., gastrointestinal string and tubes to locate internal bleeding, double lumen tube for intestinal decompression...

  10. 21 CFR 876.5980 - Gastrointestinal tube and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Gastrointestinal tube and accessories. 876.5980... tube and accessories. (a) Identification. A gastrointestinal tube and accessories is a device that..., gastrointestinal string and tubes to locate internal bleeding, double lumen tube for intestinal decompression...

  11. 21 CFR 876.5980 - Gastrointestinal tube and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Gastrointestinal tube and accessories. 876.5980... tube and accessories. (a) Identification. A gastrointestinal tube and accessories is a device that..., gastrointestinal string and tubes to locate internal bleeding, double lumen tube for intestinal decompression...

  12. 21 CFR 876.5980 - Gastrointestinal tube and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gastrointestinal tube and accessories. 876.5980... tube and accessories. (a) Identification. A gastrointestinal tube and accessories is a device that..., gastrointestinal string and tubes to locate internal bleeding, double lumen tube for intestinal decompression...

  13. Detection of accessory spleens with indium 111-labeled autologous platelets

    SciTech Connect

    Davis, H.H., II; Varki, A.; Heaton, W.A.; Siegel, B.A.

    1980-01-01

    In two patients with recurrent immune thrombocytopenia, accessory splenic tissue was demonstrated by radionuclide imaging following administration of indium 111-labeled autologous platelets. In one of these patients, no accessory splenic tissue was seen on images obtained with technetium 99m sulfur colloid. This new technique provides a simple means for demonstrating accessory spleens and simultaneously evaluating the life-span of autologous platelets.

  14. A Generalized DIF Effect Variance Estimator for Measuring Unsigned Differential Test Functioning in Mixed Format Tests

    ERIC Educational Resources Information Center

    Penfield, Randall D.; Algina, James

    2006-01-01

    One approach to measuring unsigned differential test functioning is to estimate the variance of the differential item functioning (DIF) effect across the items of the test. This article proposes two estimators of the DIF effect variance for tests containing dichotomous and polytomous items. The proposed estimators are direct extensions of the…

  15. A Comparison of Function-Based Differential Reinforcement Interventions for Children Engaging in Disruptive Classroom Behavior

    ERIC Educational Resources Information Center

    LeGray, Matthew W.; Dufrene, Brad A.; Sterling-Turner, Heather; Olmi, D. Joe; Bellone, Katherine

    2010-01-01

    This study provides a direct comparison of differential reinforcement of other behavior (DRO) and differential reinforcement of alternative behavior (DRA). Participants included three children in center-based classrooms referred for functional assessments due to disruptive classroom behavior. Functional assessments included interviews and brief…

  16. The MIMIC Model as a Tool for Differential Bundle Functioning Detection

    ERIC Educational Resources Information Center

    Finch, W. Holmes

    2012-01-01

    Increasingly, researchers interested in identifying potentially biased test items are encouraged to use a confirmatory, rather than exploratory, approach. One such method for confirmatory testing is rooted in differential bundle functioning (DBF), where hypotheses regarding potential differential item functioning (DIF) for sets of items (bundles)…

  17. The Item Parameter Replication Method for Detecting Differential Functioning in the Polytomous DFIT Framework

    ERIC Educational Resources Information Center

    Raju, Nambury S.; Fortmann-Johnson, Kristen A.; Kim, Wonsuk; Morris, Scott B.; Nering, Michael L.; Oshima, T. C.

    2009-01-01

    The recent study of Oshima, Raju, and Nanda proposes the item parameter replication (IPR) method for assessing statistical significance of the noncompensatory differential item functioning (NCDIF) index within the differential functioning of items and tests (DFIT) framework. Previous Monte Carlo simulations have found that the appropriate cutoff…

  18. A Nested Logit Approach for Investigating Distractors as Causes of Differential Item Functioning

    ERIC Educational Resources Information Center

    Suh, Youngsuk; Bolt, Daniel M.

    2011-01-01

    In multiple-choice items, differential item functioning (DIF) in the correct response may or may not be caused by differentially functioning distractors. Identifying distractors as causes of DIF can provide valuable information for potential item revision or the design of new test items. In this paper, we examine a two-step approach based on…

  19. Epigenetic control of myeloid cell differentiation, identity and function.

    PubMed

    Álvarez-Errico, Damiana; Vento-Tormo, Roser; Sieweke, Michael; Ballestar, Esteban

    2015-01-01

    Myeloid cells are crucial effectors of the innate immune response and important regulators of adaptive immunity. The differentiation and activation of myeloid cells requires the timely regulation of gene expression; this depends on the interplay of a variety of elements, including transcription factors and epigenetic mechanisms. Epigenetic control involves histone modifications and DNA methylation, and is coupled to lineage-specifying transcription factors, upstream signalling pathways and external factors released in the bone marrow, blood and tissue environments. In this Review, we highlight key epigenetic events controlling myeloid cell biology, focusing on those related to myeloid cell differentiation, the acquisition of myeloid identity and innate immune memory.

  20. Three different clinical faces of the same histopathological entity: hair follicle nevus, trichofolliculoma and accessory tragus*

    PubMed Central

    Karabulut, Yasemin Yuyucu; Şenel, Engin; Karabulut, Hacı Halil; Dölek, Yasemin

    2015-01-01

    BACKGROUND Hair follicle nevus is a rare, congenital hamartoma with follicular differentiation characterized histologically by numerous, tiny, mature hair follicles. Trichofolliculoma, the histopathological features of which are quite similar to those of hair follicle nevus, is also a hamartoma that differs from hair follicle. Accessory tragus is a relatively common, benign congenital abnormality of the external ear with an incidence rate of 1 to 10 per 1,000 live births. OBJECTIVE This study seeks to assess the discriminatory value of currently available, histological criteria in the differential diagnosis of hair follicle nevus, accessory tragi and trichofolliculoma. METHODS Twenty-one patients comprising 9 cases of hair follicle nevus, 8 accessory tragi patients and 4 trichofolliculoma cases, were recruited to perform the study. RESULTS There were 10 males and 11 females in the study group. No significant difference was observed between the three study groups in terms of age, gender or histopathological parameters such as density of hair follicles, subcutaneous fat score and presence of connective tissue framework. Cartilaginous component was seen in 8 cases that were diagnosed as accessory tragi, while central cyst and radiating hair follicles were seen in 4 cases which were diagnosed as trichofolliculoma. CONCLUSION The results of our study showed that diagnostic discrimination of these diseases could be made only with the clinicopathologic correlation because of their clinical and histopathological similarities. PMID:26375221

  1. Accessories after the facts: Constraining the timing, duration and conditions of high-temperature metamorphic processes

    NASA Astrophysics Data System (ADS)

    Taylor, Richard J. M.; Kirkland, Christopher L.; Clark, Chris

    2016-11-01

    High-temperature metamorphic rocks are the result of numerous chemical and physical processes that occur during a potentially long-lived thermal evolution. These rocks chart the sequence of events during an orogenic episode including heating, cooling, exhumation and melt interaction, all of which may be interpreted through the elemental and isotopic characteristics of accessory minerals such as zircon, monazite and rutile. Developments in imaging and in situ chemical analysis have resulted in an increasing amount of information being extracted from these accessory phases. The refractory nature of these minerals, combined with both their use as geochronometers and tracers of metamorphic mineral reactions, has made them the focus of many studies of granulite-facies terrains. In such studies the primary aim is often to determine the timing and conditions of the peak of metamorphism, and high-temperature metasedimentary rocks may seem ideal for this purpose. For example pelites typically contain an abundance of accessory minerals in a variety of bulk compositions, are melt-bearing, and may have endured extreme conditions that facilitate diffusion and chemical equilibrium. However complexities arise due to the heterogeneous nature of these rocks on all scales, driven by both the composition of the protolith and metamorphic differentiation. In additional to lithological heterogeneity, the closure temperatures for both radiogenic isotopes and chemical thermometers vary between different accessory minerals. This apparent complexity can be useful as it permits a wide range of temperature and time (T-t) information to be recovered from a single rock sample. In this review we cover: 1) characteristic internal textures of accessory minerals in high temperature rocks; 2) the interpretation of zircon and monazite age data in relation to high temperature processes; 3) rare earth element partitioning; 4) trace element thermometry; 5) the incorporation of accessory mineral growth

  2. Differentiation mechanism and function of the cereal aleurone cells and hormone effects on them.

    PubMed

    Zheng, Yankun; Wang, Zhong

    2014-11-01

    The cereal aleurone cells differentiate from the endosperm epidermis with the exception of endosperm transfer cells. Aleurone cells contain proteins, lipids, and minerals, and are important for digesting the endosperm storage products to nurse the embryo under effects of several hormones during the seed germination. The differentiation of aleurone cells is related to location effect and special gene expression. Moreover, the differentiation of aleurone cells is probably affected by the cues from maternal tissues. In the paper, differentiation mechanism and function of aleurone cells and hormone effects on them are reviewed. Some speculations about the differentiation mechanism of aleurone cells are given here.

  3. Subicular and CA1 hippocampal projections to the accessory olfactory bulb.

    PubMed

    de la Rosa-Prieto, C; Ubeda-Banon, I; Mohedano-Moriano, A; Pro-Sistiaga, P; Saiz-Sanchez, D; Insausti, R; Martinez-Marcos, A

    2009-02-01

    The hippocampal formation is anatomically and functionally related to the olfactory structures especially in rodents. The entorhinal cortex (EC) receives afferent projections from the main olfactory bulb; this constitutes an olfactory pathway to the hippocampus. In addition to the olfactory system, most mammals possess an accessory olfactory (or vomeronasal) system. The relationships between the hippocampal formation and the vomeronasal system are virtually unexplored. Recently, a centrifugal projection from CA1 to the accessory olfactory bulb has been identified using anterograde tracers. In the study reported herein, experiments using anterograde tracers confirm this projection, and injections of retrograde tracers show the distribution and morphology of a population of CA1 and ventral subicular neurons projecting to the accessory olfactory bulb of rats. These results extend previous descriptions of hippocampal projections to the accessory olfactory bulb by including the ventral subiculum and characterizing the morphology, neurochemistry (double labeling with somatostatin), and distribution of such neurons. These data suggest feedback hippocampal control of chemosensory stimuli in the accessory olfactory bulb. Whether this projection processes spatial information on conspecifics or is involved in learning and memory processes associated with chemical stimuli remains to be elucidated.

  4. Spline Approximation for Autonomous Nonlinear Functional Differential Equations.

    DTIC Science & Technology

    1980-06-18

    Af(e / a e(-T)/ P(T)dT) + q. An easy calculation using (H2) shows that h has the Lipschitz constant XL(m+l+r1 /2) on In. This proves b) with X0 = i/L...84A(1979), 71-91. [13] R.D. Nussbaum, Uniqueness and nonuniqueness for periodic solutions of x’(t) - -g(x(t-1)), J. Differential Eqs. 34(1979), 25-54

  5. Intrapancreatic Accessory Spleen: A Diagnosis Not to Forget!

    PubMed Central

    Marques, Susana; Bispo, Miguel; Noia, Lariño

    2016-01-01

    A 69-year-old male patient was incidentally diagnosed with a 5-mm lesion in the pancreatic tail by endoscopic ultrasound (EUS). After contrast-enhanced EUS and EUS-elastography, all imaging features were highly suggestive of a benign pancreatic solid lesion such as an intrapancreatic accessory spleen (IPAS) or a benign neuroendocrine tumor. Interposition of the splenic artery precluded EUS-guided fine-needle aspiration (FNA). When an asymptomatic pancreatic mass is detected, IPAS diagnosis should be considered, and, if EUS-FNA is infeasible, contrast-enhanced EUS and EUS-elastography are useful tools to differentiate a pancreatic benign lesion as IPAS from a malignancy, with avoidance of unnecessary surgery. PMID:28100996

  6. T Cell Receptor Signaling in the Control of Regulatory T Cell Differentiation and Function

    PubMed Central

    Li, Ming O.; Rudensky, Alexander Y.

    2016-01-01

    Regulatory T cells (TReg cells), a specialized T cell lineage, have a pivotal function in the control of self-tolerance and inflammatory responses. Recent studies have revealed a discrete mode of TCR signaling that regulates Treg cell differentiation, maintenance and function and that impacts on gene expression, metabolism, cell adhesion and migration of these cells. Here, we discuss the emerging understanding of TCR-guided differentiation of Treg cells in the context of their function in health and disease. PMID:27026074

  7. Accessory cells for β-cell transplantation.

    PubMed

    Staels, W; De Groef, S; Heremans, Y; Coppens, V; Van Gassen, N; Leuckx, G; Van de Casteele, M; Van Riet, I; Luttun, A; Heimberg, H; De Leu, N

    2016-02-01

    Despite recent advances, insulin therapy remains a treatment, not a cure, for diabetes mellitus with persistent risk of glycaemic alterations and life-threatening complications. Restoration of the endogenous β-cell mass through regeneration or transplantation offers an attractive alternative. Unfortunately, signals that drive β-cell regeneration remain enigmatic and β-cell replacement therapy still faces major hurdles that prevent its widespread application. Co-transplantation of accessory non-islet cells with islet cells has been shown to improve the outcome of experimental islet transplantation. This review will highlight current travails in β-cell therapy and focuses on the potential benefits of accessory cells for islet transplantation in diabetes.

  8. ESF GROUND SUPPORT - MATERIAL DEDICATION ANALYSIS FOR STRUCTURAL STEEL AND ACCESSORIES FROM A COMMERCIAL GRADE SOURCE

    SciTech Connect

    M.D. Stine

    1996-01-23

    The purpose of this analysis is to select the critical characteristics to be verified for steel sets and accessories and the verification methods to be implemented through a material dedication process for the procurement and use of commercial grade structural steel sets and accessories (which have a nuclear safety function) to be used in ground support (with the exception of alcove ground support and alcove opening framing, which are not addressed in this analysis) for the Exploratory Studies Facility (ESF) Topopah Spring (TS) Loop. The ESF TS Loop includes the North Ramp, Main Drift, and South Ramp underground openings.

  9. Lateral facial cleft associated with accessory mandible having teeth, absent parotid gland and peripheral facial weakness.

    PubMed

    Ozçelik, D; Toplu, G; Türkseven, A; Senses, D A; Yiğit, B

    2014-07-01

    Transverse facial cleft is a very rare malformation. The Tessier no. 7 cleft is a lateral facial cleft which emanates from oral cavity and extends towards the tragus, involving both soft tissue and skeletal components. Here, we present a case having transverse facial cleft, accessory mandible having teeth, absent parotid gland and ipsilateral peripheral facial nerve weakness. After surgical repair of the cleft in 2-month of age, improvement of the facial nerve function was detected in 3-year of age. Resection of the accessory mandible was planned in 5-6 years of age.

  10. Behavior near constant solutions of functional differential equations

    NASA Technical Reports Server (NTRS)

    Hale, J. K.

    1974-01-01

    Techniques have been developed to determine in a systematic way the local behavior near constant solutions. Local integral manifolds play a very important role in this development, as they have also for ordinary differential equations. An attempt is made to indicate a few more applications of these methods to some problems in bifurcation in the spirit of Sotomayor (to appear) and to a growth model of Cooke and Yorke (to appear). It is also shown how to prove a theorem on stability under constantly acting disturbances using these methods.

  11. Exploring Differential Bundle Functioning in Mathematics by Gender: The Effect of Hierarchical Modelling

    ERIC Educational Resources Information Center

    Ong, Yoke Mooi; Williams, Julian; Lamprianou, Iasonas

    2013-01-01

    Researchers interested in exploring substantive group differences are increasingly attending to bundles of items (or testlets): the aim is to understand how gender differences, for instance, are explained by differential performances on different types or bundles of items, hence differential bundle functioning (DBF). Some previous work has…

  12. Green's functional for a higher order ordinary integro-differential equation with nonlocal conditions

    NASA Astrophysics Data System (ADS)

    Özen, Kemal

    2016-12-01

    One of the little-known techniques for ordinary integro-differential equations in literature is Green's functional method, the origin of which dates back to Azerbaijani scientist Seyidali S. Akhiev. According to this method, Green's functional concepts for some simple forms of such equations have been introduced in the several studies. In this study, we extend Green's functional concept to a higher order ordinary integro-differential equation involving generally nonlocal conditions. A novel kind of adjoint problem and Green's functional are constructed for completely nonhomogeneous problem. By means of the obtained Green's functional, the solution to the problem is identified.

  13. The accessory limb model: an alternative experimental system of limb regeneration.

    PubMed

    Endo, Tetsuya; Gardiner, David M; Makanae, Aki; Satoh, Akira

    2015-01-01

    Accessory limb model (ALM) was developed as an experimental model and functional assay for limb regeneration. The ALM provides several ways to identify pathways and test for signaling molecules that regulate limb regeneration. Here, we summarize the history of the ALM and describe the specific details involved in inducing ectopic blastemas and limbs from a skin wound on the side of the arm.

  14. Collective Dynamics Differentiates Functional Divergence in Protein Evolution

    PubMed Central

    Glembo, Tyler J.; Farrell, Daniel W.; Gerek, Z. Nevin; Thorpe, M. F.; Ozkan, S. Banu

    2012-01-01

    Protein evolution is most commonly studied by analyzing related protein sequences and generating ancestral sequences through Bayesian and Maximum Likelihood methods, and/or by resurrecting ancestral proteins in the lab and performing ligand binding studies to determine function. Structural and dynamic evolution have largely been left out of molecular evolution studies. Here we incorporate both structure and dynamics to elucidate the molecular principles behind the divergence in the evolutionary path of the steroid receptor proteins. We determine the likely structure of three evolutionarily diverged ancestral steroid receptor proteins using the Zipping and Assembly Method with FRODA (ZAMF). Our predictions are within ∼2.7 Å all-atom RMSD of the respective crystal structures of the ancestral steroid receptors. Beyond static structure prediction, a particular feature of ZAMF is that it generates protein dynamics information. We investigate the differences in conformational dynamics of diverged proteins by obtaining the most collective motion through essential dynamics. Strikingly, our analysis shows that evolutionarily diverged proteins of the same family do not share the same dynamic subspace, while those sharing the same function are simultaneously clustered together and distant from those, that have functionally diverged. Dynamic analysis also enables those mutations that most affect dynamics to be identified. It correctly predicts all mutations (functional and permissive) necessary to evolve new function and ∼60% of permissive mutations necessary to recover ancestral function. PMID:22479170

  15. Dermal fibroblasts contribute to multiple tissues in the accessory limb model.

    PubMed

    Hirata, Ayako; Gardiner, David M; Satoh, Akira

    2010-05-01

    The accessory limb model has become an alternative model for performing investigations of limb regeneration in an amputated limb. In the accessory limb model, a complete patterned limb can be induced as a result of an interaction between the wound epithelium, a nerve and dermal fibroblasts in the skin. Studies should therefore focus on examining these tissues. To date, however, a study of cellular contributions in the accessory limb model has not been reported. By using green fluorescent protein (GFP) transgenic axolotl tissues, we can trace cell fate at the tissue level. Therefore, in the present study, we transgrafted GFP skin onto the limb of a non-GFP host and induced an accessory limb to investigate cellular contributions. Previous studies of cell contribution to amputation-induced blastemas have demonstrated that dermal cells are the progenitors of many of the early blastema cells, and that these cells contribute to regeneration of the connective tissues, including cartilage. In the present study, we have determined that this same population of progenitor cells responds to signaling from the nerve and wound epithelium in the absence of limb amputation to form an ectopic blastema and regenerate the connective tissues of an ectopic limb. Blastema cells from dermal fibroblasts, however, did not differentiate into either muscle or neural cells, and we conclude that dermal fibroblasts are dedifferentiated along its developmental lineage.

  16. A Rasch Differential Item Functioning Analysis of the Massachusetts Youth Screening Instrument: Identifying Race and Gender Differential Item Functioning among Juvenile Offenders

    ERIC Educational Resources Information Center

    Cauffman, Elizabeth; MacIntosh, Randall

    2006-01-01

    The juvenile justice system needs a tool that can identify and assess mental health problems among youths quickly with validity and reliability. The goal of this article is to evaluate the racial/ethnic and gender differential item functioning (DIF) of the Massachusetts Youth Screening Instrument-Second Version (MAYSI-2) using the Rasch Model.…

  17. On the Relationship between Differential Item Functioning and Item Difficulty: An Issue of Methods? Item Response Theory Approach to Differential Item Functioning

    ERIC Educational Resources Information Center

    Santelices, Maria Veronica; Wilson, Mark

    2012-01-01

    The relationship between differential item functioning (DIF) and item difficulty on the SAT is such that more difficult items tended to exhibit DIF in favor of the focal group (usually minority groups). These results were reported by Kulick and Hu, and Freedle and have been enthusiastically discussed by more recent literature. Examining the…

  18. A Monte Carlo Study Investigating the Influence of Item Discrimination, Category Intersection Parameters, and Differential Item Functioning Patterns on the Detection of Differential Item Functioning in Polytomous Items

    ERIC Educational Resources Information Center

    Thurman, Carol

    2009-01-01

    The increased use of polytomous item formats has led assessment developers to pay greater attention to the detection of differential item functioning (DIF) in these items. DIF occurs when an item performs differently for two contrasting groups of respondents (e.g., males versus females) after controlling for differences in the abilities of the…

  19. Chondrocytic Atf4 regulates osteoblast differentiation and function via Ihh

    PubMed Central

    Wang, Weiguang; Lian, Na; Ma, Yun; Li, Lingzhen; Gallant, Richard C.; Elefteriou, Florent; Yang, Xiangli

    2012-01-01

    Atf4 is a leucine zipper-containing transcription factor that activates osteocalcin (Ocn) in osteoblasts and indian hedgehog (Ihh) in chondrocytes. The relative contribution of Atf4 in chondrocytes and osteoblasts to the regulation of skeletal development and bone formation is poorly understood. Investigations of the Atf4–/–;Col2a1-Atf4 mouse model, in which Atf4 is selectively overexpressed in chondrocytes in an Atf4-null background, demonstrate that chondrocyte-derived Atf4 regulates osteogenesis during development and bone remodeling postnatally. Atf4 overexpression in chondrocytes of the Atf4–/–;Col2a1-Atf4 double mutants corrects the reduction in stature and limb in Atf4–/– embryos and rectifies the decrease in Ihh expression, Hh signaling, proliferation and accelerated hypertrophy that characterize the Atf4–/– developing growth plate cartilages. Unexpectedly, this genetic manipulation also restores the expression of osteoblastic marker genes, namely Ocn and bone sialoprotein, in Atf4–/– developing bones. In Atf4–/–;Col2a1-Atf4 adult mice, all the defective bone parameters found in Atf4–/– mice, including bone volume, trabecular number and thickness, and bone formation rate, are rescued. In addition, the conditioned media of ex vivo cultures from wild-type or Atf4–/–;Col2a1-Atf4, but not Atf4–/– cartilage, corrects the differentiation defects of Atf4–/– bone marrow stromal cells and Ihh-blocking antibody eliminates this effect. Together, these data indicate that Atf4 in chondrocytes is required for normal Ihh expression and for its paracrine effect on osteoblast differentiation. Therefore, the cell-autonomous role of Atf4 in chondrocytes dominates the role of Atf4 in osteoblasts during development for the control of early osteogenesis and skeletal growth. PMID:22190639

  20. Regulation of ES cell differentiation by functional and conformational modulation of p53.

    PubMed Central

    Sabapathy, K; Klemm, M; Jaenisch, R; Wagner, E F

    1997-01-01

    Embryonic stem (ES) cell lines were used to examine the role of p53 during in vitro differentiation. Undifferentiated ES cells express high levels of p53 exclusively in the wild-type conformation, immunoprecipitable by monoclonal antibody PAb246, and p53 was found to be functionally active as determined by its ability to bind DNA specifically and to activate transcription of target genes. Differentiation in vitro resulted in a decrease in the levels of p53 and in a shift in its conformational status to the mutant form, detectable by monoclonal antibody PAb240, with a concomitant loss of functional activity. The presence of functional p53 in the undifferentiated ES cells renders them hypersensitive to UV irradiation, whereas the differentiated cells were resistant to UV treatment. ES cells lacking p53 exhibit enhanced proliferation in both the undifferentiated and differentiated state, and apoptosis accompanying differentiation was found to be reduced. Furthermore, wild-type ES cells undergoing apoptosis expressed functional p53. Expression of the temperature-sensitive p53val135 mutant in wild-type ES cells resulted in a reduction of apoptosis accompanying differentiation when it adopted a mutant conformation at 39 degrees C. These data demonstrate that functional inactivation of p53 allows differentiating cells to escape from apoptosis, and suggest that the conformational switch could regulate the inactivation process. PMID:9321401

  1. Accessories to the crime: recent advances in HIV accessory protein biology.

    PubMed

    Gramberg, Thomas; Sunseri, Nicole; Landau, Nathaniel R

    2009-02-01

    Recent advances in understanding the roles of the lentiviral accessory proteins have provided fascinating insight into the molecular biology of the virus and uncovered previously unappreciated innate immune mechanisms by which the host defends itself. HIV-1 and other lentiviruses have developed accessory proteins that counterattack the antiviral defenses in a sort of evolutionary battle. The virus is remarkably adept at co-opting cellular degradative pathways to destroy the protective proteins. This review focuses on recent advances in understanding three of the accessory proteins-virion infectivity factor (Vif), viral protein R (Vpr), and viral protein U (Vpu)-that target different restriction factors to ensure virus replication. These proteins may provide promising targets for the development of novel classes of antiretroviral drugs.

  2. Differential engagement of anterior cingulate cortex subdivisions for cognitive and emotional function.

    PubMed

    Mohanty, Aprajita; Engels, Anna S; Herrington, John D; Heller, Wendy; Ho, Moon-Ho Ringo; Banich, Marie T; Webb, Andrew G; Warren, Stacie L; Miller, Gregory A

    2007-05-01

    Functional differentiation of dorsal (dACC) and rostral (rACC) anterior cingulate cortex for cognitive and emotional function has received considerable indirect support. Using fMRI, parallel tasks, and within-subject analysis, the present study directly tested the proposed specialization of ACC subdivisions. A Task x Region interaction confirmed more dACC activation during color-word distractors and more rACC activation during emotion-word distractors. Activity in ACC subdivisions differentially predicted behavioral performance. Connectivity with prefrontal and limbic regions also supported distinct dACC and rACC roles. Findings provide direct evidence for differential engagement of ACC subdivisions in cognitive and emotional processing and for differential functional connectivity in the implementation of cognitive control and emotion regulation. Results point to an anatomical and functional continuum rather than segregated operations.

  3. Illustrating the Use of Nonparametric Regression To Assess Differential Item and Bundle Functioning among Multiple Groups.

    ERIC Educational Resources Information Center

    Gierl, Mark J.; Bolt, Daniel M.

    2001-01-01

    Presents an overview of nonparametric regression as it allies to differential item functioning analysis and then provides three examples to illustrate how nonparametric regression can be applied to multilingual, multicultural data to study group differences. (SLD)

  4. Is the full susceptibility of the square-lattice Ising model a differentially algebraic function?

    NASA Astrophysics Data System (ADS)

    Guttmann, A. J.; Jensen, I.; Maillard, J.-M.; Pantone, J.

    2016-12-01

    We study the class of non-holonomic power series with integer coefficients that reduce, modulo primes, or powers of primes, to algebraic functions. In particular we try to determine whether the susceptibility of the square-lattice Ising model belongs to this class, and more broadly whether the susceptibility is a solution of a differentially algebraic equation. Initial results on Tutte's nonlinear ordinary differential equation (ODE) and other simple quadratic nonlinear ODEs suggest that a large set of differentially algebraic power series solutions with integer coefficients might reduce to algebraic functions modulo primes, or powers of primes. Since diagonals of rational functions are well-known to reduce, modulo primes, or powers of primes, to algebraic functions, a large subset of differentially algebraic power series with integer coefficients may be viewed as a natural ‘nonlinear’ generalisation of diagonals of rational functions. Here we give several examples of series with integer coefficients and non-zero radius of convergence that reduce to algebraic functions modulo (almost) every prime (or power of a prime). These examples satisfy differentially algebraic equations with the encoding polynomial occasionally possessing quite high degree (and thus difficult to identify even with long series). These examples shed important light on the very nature of such differentially algebraic series. Additionally, we have extended both the high- and low-temperature Ising square-lattice susceptibility series to 5043 coefficients. We find that even this long series is insufficient to determine whether it reduces to algebraic functions modulo 3, 5, etc. This negative result is in contrast to the comparatively easy confirmation that the corresponding series reduce to algebraic functions modulo powers of 2. Finally we show that even with 5043 terms we are unable to identify an underlying differentially algebraic equation for the susceptibility, ruling out a number of

  5. Zebrafish Functional Genetics Approach to the Pathogenesis of Well-Differentiated Liposarcoma

    DTIC Science & Technology

    2015-12-01

    AWARD NUMBER: W81XWH-13-1-0340 TITLE: Zebrafish Functional Genetics Approach to the Pathogenesis of Well- Differentiated Liposarcoma PRINCIPAL...2013 - 14 Sep 2015 4. TITLE AND SUBTITLE Zebrafish Functional Genetics Approach to the Pathogenesis of Well-Differentiated Liposarcoma 5a...that FRS2 is a 12q oncogene that activates oncogenic signal transduction, using FRS2 overexpression in genetically engineered zebrafish models and in

  6. Regeneration niche differentiates functional strategies of desert woody plant species

    PubMed Central

    Briggs, John M.

    2010-01-01

    Plant communities vary dramatically in the number and relative abundance of species that exhibit facilitative interactions, which contributes substantially to variation in community structure and dynamics. Predicting species’ responses to neighbors based on readily measurable functional traits would provide important insight into the factors that structure plant communities. We measured a suite of functional traits on seedlings of 20 species and mature plants of 54 species of shrubs from three arid biogeographic regions. We hypothesized that species with different regeneration niches—those that require nurse plants for establishment (beneficiaries) versus those that do not (colonizers)—are functionally different. Indeed, seedlings of beneficiary species had lower relative growth rates, larger seeds and final biomass, allocated biomass toward roots and height at a cost to leaf mass fraction, and constructed costly, dense leaf and root tissues relative to colonizers. Likewise at maturity, beneficiaries had larger overall size and denser leaves coupled with greater water use efficiency than colonizers. In contrast to current hypotheses that suggest beneficiaries are less “stress-tolerant” than colonizers, beneficiaries exhibited conservative functional strategies suited to persistently dry, low light conditions beneath canopies, whereas colonizers exhibited opportunistic strategies that may be advantageous in fluctuating, open microenvironments. In addition, the signature of the regeneration niche at maturity indicates that facilitation expands the range of functional diversity within plant communities at all ontogenetic stages. This study demonstrates the utility of specific functional traits for predicting species’ regeneration niches in hot deserts, and provides a framework for studying facilitation in other severe environments. Electronic supplementary material The online version of this article (doi:10.1007/s00442-010-1741-y) contains supplementary

  7. Steroidogenesis by testis and accessory glands of the Lusitanian toadfish, Halobatrachus didactylus, during reproductive season.

    PubMed

    Modesto, Teresa; Freitas, Ana M M S; Canario, Adelino V M

    2015-11-01

    In teleost fish sex steroids are essential for gonadal function and have marked effects in reproductive and agonistic behavior and in the expression of secondary sexual characteristics. The Lusitanian toadfish, Halobatrachus didactylus, has two male morphotypes: type I males are territorial nest-holders and have large accessory glands while type II males are smaller, have a relatively large testis and small accessory glands. In the present study, the steroidogenic activity of the testis and accessory testicular glands of the Lusitanian toadfish were examined in vitro as well as their presence in urine. The testis of type I males produced 11-ketotestosterone (11KT) and 11β-hydroxy-4-androstene-3,17-dione (11βA) from tritiated 17-hydroxyprogesterone, while those of type II males produced testosterone (T) and 11β,17β-dihydroxy-4-andosten-3-one (11βT), but not 11KT. Additionally, the testis and accessory glands of both morphs produced mostly 5β,3α-reduced and 17,20α-hydroxylated metabolites. Type I, but not of type II, males synthesised 5β-reduced androgens in their accessory glands. The presence of 11βA exclusively in the urine of type I males during reproductive season suggests an association with maintenance of secondary sexual characteristics and behavior in this morph. The urine of both types of males contained two 5α-androstane and 5β-pregnane glucuronides. Among the latter steroids, those that are 17,21-dihydroxylated are potentially metabolites from cortisol and were found only in type I males during the spawning season. The diversity of metabolites produced by the testis and accessory glands and the presence of some in urine is suggestive of a potential role in chemical communication and reproductive behavior.

  8. Promoting effect of lactoferrin on barrier function and epithelial differentiation of human keratinocytes.

    PubMed

    Uchida, Ryo; Aoki, Reiji; Aoki-Yoshida, Ayako; Tajima, Atsushi; Takayama, Yoshiharu

    2017-02-01

    The purpose of this study was to elucidate the effects of bovine lactoferrin on keratinocyte differentiation and barrier function. Addition of bovine lactoferrin to differentiating HaCaT human keratinocytes led to increased transepithelial electrical resistance (TER), a marker of epithelial barrier function. This elevation was followed by upregulation of two differentiation markers, involucrin and filaggrin. The expression level of sterol regulatory element-binding protein-1 was also enhanced by bovine lactoferrin. The lactoferrin-induced upregulation of involucrin and filaggrin expression were confirmed in normal human epidermal keratinocytes (NHEK). Treatment with SB203580, a p38 mitogen-activated protein kinase (MAPK) α inhibitor, impaired the upregulation of involucrin and filaggrin expression in response to lactoferrin. The elevation of p38 MAPK phosphorylation was further enhanced by lactoferrin in the initial stage of differentiation of HaCaT keratinocytes. The findings suggest that bovine lactoferrin promotes epithelial differentiation by a p38-MAPK-dependent mechanism.

  9. Integral estimates for differentiable functions on irregular domains

    SciTech Connect

    Besov, Oleg V

    2011-02-11

    Integral representations for functions and their partial derivatives in terms of some fixed system of partial derivatives are constructed on irregular domains in a Euclidean space. Embedding theorems for Sobolev-type spaces into a Lebesgue space are established and the norms of the derivatives are estimated. Bibliography: 17 titles.

  10. Differentiating High-Functioning Autism and Social Phobia

    ERIC Educational Resources Information Center

    Tyson, Katherine E.; Cruess, Dean G.

    2012-01-01

    Both high-functioning autism (HFA) and social phobia (SP) involve profound social interaction deficits. Although these disorders share some similar symptoms, they are conceptualized as distinct. Because both HFA and SP are defined behaviorally, the degree of overlap between the two disorders may result in misinterpretation of symptoms. However,…

  11. Baker-Akhiezer Spinor Kernel and Tau-functions on Moduli Spaces of Meromorphic Differentials

    NASA Astrophysics Data System (ADS)

    Kalla, C.; Korotkin, D.

    2014-11-01

    In this paper we study the Baker-Akhiezer spinor kernel on moduli spaces of meromorphic differentials on Riemann surfaces. We introduce the Baker-Akhiezer tau-function which is related to both the Bergman tau-function (which was studied before in the context of Hurwitz spaces and spaces of holomorphic Abelian and quadratic differentials) and the KP tau-function on such spaces. In particular, we derive variational formulas of Rauch-Ahlfors type on moduli spaces of meromorphic differentials with prescribed singularities: we use the system of homological coordinates, consisting of absolute and relative periods of the meromorphic differential, and show how to vary the fundamental objects associated to a Riemann surface (the matrix of b-periods, normalized Abelian differentials, the Bergman bidifferential, the Szegö kernel and the Baker-Akhiezer spinor kernel) with respect to these coordinates. The variational formulas encode dependence both on the moduli of the Riemann surface and on the choice of meromorphic differential (variation of the meromorphic differential while keeping the Riemann surface fixed corresponds to flows of KP type). Analyzing the global properties of the Bergman and Baker-Akhiezer tau-functions, we establish relationships between various divisor classes on the moduli spaces.

  12. Autophagy is required for CSF-1-induced macrophagic differentiation and acquisition of phagocytic functions.

    PubMed

    Jacquel, Arnaud; Obba, Sandrine; Boyer, Laurent; Dufies, Maeva; Robert, Guillaume; Gounon, Pierre; Lemichez, Emmanuel; Luciano, Frederic; Solary, Eric; Auberger, Patrick

    2012-05-10

    Autophagy is the process by which superfluous or damaged macromolecules or organelles are degraded by the lysosome. Pharmacologic and genetic evidence indicates that autophagy plays pleiotropic functions in cellular homeostasis, development, survival, and differentiation. The differentiation of human blood monocytes into macrophages is a caspase-dependent process when triggered ex vivo by colony stimulating factor-1. We show here, using pharmacologic inhibitors, siRNA approaches, and Atg7-/- mice, that autophagy initiated by ULK1 is required for proper colony stimulating factor-1-driven differentiation of human and murine monocytes. We also unravel a role for autophagy in macrophage acquisition of phagocytic functions. Collectively, these findings highlight an unexpected and essential role of autophagy during monocyte differentiation and acquisition of macrophage functions.

  13. Boundary-value problems for elliptic functional-differential equations and their applications

    NASA Astrophysics Data System (ADS)

    Skubachevskii, A. L.

    2016-10-01

    Boundary-value problems are considered for strongly elliptic functional-differential equations in bounded domains. In contrast to the case of elliptic differential equations, smoothness of generalized solutions of such problems can be violated in the interior of the domain and may be preserved only on some subdomains, and the symbol of a self-adjoint semibounded functional-differential operator can change sign. Both necessary and sufficient conditions are obtained for the validity of a Gårding-type inequality in algebraic form. Spectral properties of strongly elliptic functional-differential operators are studied, and theorems are proved on smoothness of generalized solutions in certain subdomains and on preservation of smoothness on the boundaries of neighbouring subdomains. Applications of these results are found to the theory of non-local elliptic problems, to the Kato square-root problem for an operator, to elasticity theory, and to problems in non-linear optics. Bibliography: 137 titles.

  14. Decontamination of minimally invasive surgical endoscopes and accessories.

    PubMed

    Ayliffe, G

    2000-08-01

    lung function testing by spirometry. (7) Possible alternative disinfectants to glutaraldehyde include peracetic acid (0.2-0.35%), chlorine dioxide (700-1100 ppm) and superoxidized water. These are very effective, killing vegetative bacteria, including mycobacteria, and viruses in 5 min and bacterial spores in 10 min. An endorsement of compatibility with endoscopes, accessories and processing equipment is required from both the solution/device manufacturer and the endoscope manufacturer. Other important considerations are stability, cost and safety from the user and environmental standpoints. (8) Cleaning and disinfection or sterilization should be undertaken by trained staff in a dedicated area, e.g., SSD or TSSU. A suitable training programme is described. (9) If endoscopes are processed by immersion in disinfectants, harmful residues must be removed by thorough rinsing. Sterile or bacteria free water is essential for rinsing all invasive endoscopes and accessories to prevent recontamination. (10) If an automated washer disinfector is used it must be effective, non-damaging, reliable, easy to use and its performance regularly monitored. (11) If used, washer disinfectors and other processing equipment should be disinfected on a regular basis, i.e., between patients or at the start of each session. This will prevent biofilm formation and recontamination of instruments during rinsing. Disinfection should include the water treatment system, if present. (12) To comply with the Medical Devices Directive, manufacturers are obliged to provide full details on how to decontaminate the reusable devices they supply. This should include details of compatibility with heat, pressure, moisture, processing chemicals and ultrasonics. (13) The Infection Control Team should always be involved in the formulation and implementation of decontamination policies. Wherever possible, the national good practice guidelines produced by the Medical Devices Agency and/or professional societies shoul

  15. Differential functional effects of biomaterials on dendritic cell maturation.

    PubMed

    Park, Jaehyung; Babensee, Julia E

    2012-10-01

    The immunological outcome of dendritic cell (DC) treatment with different biomaterials was assessed to demonstrate the range of DC phenotypes induced by biomaterials commonly used in combination products. Immature DCs (iDCs) were derived from human peripheral blood monocytes, and treated with different biomaterial films of alginate, agarose, chitosan, hyaluronic acid (HA), or 75:25 poly(lactic-co-glycolic acid) (PLGA) and a comprehensive battery of phenotypic functional outcomes was assessed. Different levels of functional changes in DC phenotype were observed depending on the type of biomaterial films used to treat the DCs. Treatment of DCs with PLGA or chitosan films supported DC maturation, with higher levels of DC allostimulatory capacity, pro-inflammatory cytokine release, and expression of CD80, CD86, CD83, HLA-DQ and CD44 compared with iDCs, and lower endocytic ability compared with iDCs. Alginate film induced pro-inflammatory cytokine release from DCs at levels higher than from iDCs. Dendritic cells treated with HA film expressed lower levels of CD40, CD80, CD86 and HLA-DR compared with iDCs. They also exhibited lower endocytic ability and CD44 expression than iDCs, possibly due to an insolubilized (cross-linked) form of high molecular weight HA. Interestingly, treatment of DCs with agarose film maintained the DC functional phenotype at levels similar to iDCs except for CD44 expression, which was lower than that of iDCs. Taken together, these results can provide selection criteria for biomaterials to be used in immunomodulating applications and can inform potential outcomes of biomaterials within combination products on associated immune responses as desired by the application.

  16. Optimization of diffuse reflectance infrared spectroscopy accessories

    SciTech Connect

    Hirschfeld, T.

    1986-11-01

    The value of diffuse reflectance as an infrared or near-infrared spectroscopic sampling procedure has been limited by the low efficiency of accessories designed for it. In terms of signal-to-noise ratio, these average 2-6% for integrating spheres and 10-12% for various ellipsoidal mirror arrangements. Much better performances, up to 37% efficiency, can be obtained by optimizing a concentric confocal ellipsoidal mirror arrangement by using a very large central opening in the amular collector mirror, and adapting the throughput of the detector to the geometry of the collected beam.

  17. Reproductive biology in Anophelinae mosquitoes (Diptera, Culicidae): Fine structure of the female accessory gland.

    PubMed

    Laghezza Masci, Valentina; Di Luca, Marco; Gambellini, Gabriella; Taddei, Anna Rita; Belardinelli, Maria Cristina; Guerra, Laura; Mazzini, Massimo; Fausto, Anna Maria

    2015-07-01

    The morphology and ultrastructure of female accessory reproductive glands of Anopheles maculipennis s.s., Anopheles labranchiae and Anopheles stephensi were investigated by light and electron microscopy. The reproductive system in these species is characterized by two ovaries, two lateral oviducts, a single spermatheca and a single accessory gland. The gland is globular and has a thin duct which empties into the vagina, near the opening of the spermathecal duct. Significant growth of the accessory reproductive gland is observed immediately after blood meal, but not at subsequent digestion steps. At ultrastructural level, the gland consists of functional glandular units belonging to type 3 ectodermal glands. The secretory cells are elongated and goblet shaped, with most of their cytoplasm and large nucleus in the basal part, close to the basement lamella. Finely fibrous electron-transparent material occupies the secretory cavity that is in contact with the end of a short efferent duct (ductule) emerging from the gland duct. The present study is the first detailed description of female accessory gland ultrastructure in Anophelinae and provides insights into the gland's functional role in the reproductive biology of these insects.

  18. Transcriptional activation of melanocortin 2 receptor accessory protein by PPARγ in adipocytes

    SciTech Connect

    Kim, Nam Soo; Kim, Yoon-Jin; Cho, Si Young; Lee, Tae Ryong; Kim, Sang Hoon

    2013-09-27

    Highlights: •MRAP enhanced HSL expression. •ACTH-mediated MRAP reduced glycerol release. •PPARγ induced MRAP expression. •PPARγ bound to the MRAP promoter. -- Abstract: Adrenocorticotropic hormone (ACTH) in rodents decreases lipid accumulation and body weight. Melanocortin receptor 2 (MC2R) and MC2R accessory protein (MRAP) are specific receptors for ACTH in adipocytes. Peroxisome proliferator-activated receptor γ (PPARγ) plays a role in the transcriptional regulation of metabolic pathways such as adipogenesis and β-oxidation of fatty acids. In this study we investigated the transcriptional regulation of MRAP expression during differentiation of 3T3-L1 cells. Stimulation with ACTH affected lipolysis in murine mature adipocytes via MRAP. Putative peroxisome proliferator response element (PPRE) was identified in the MRAP promoter region. In chromatin immunoprecipitation and reporter assays, we observed binding of PPARγ to the MRAP promoter. The mutagenesis experiments showed that the −1209/−1198 region of the MRAP promoter could function as a PPRE site. These results suggest that PPARγ is required for transcriptional activation of the MRAP gene during adipogenesis, which contributes to understanding of the molecular mechanism of lipolysis in adipocytes.

  19. Differential macrophage function in Brown Swiss and Holstein Friesian cattle.

    PubMed

    Gibson, Amanda Jane; Woodman, Sally; Pennelegion, Christopher; Patterson, Robert; Stuart, Emma; Hosker, Naomi; Siviter, Peter; Douglas, Chloe; Whitehouse, Jessica; Wilkinson, Will; Pegg, Sherri-Anne; Villarreal-Ramos, Bernardo; Werling, Dirk

    2016-11-15

    There is strong evidence that high yielding dairy cows are extremely susceptible to infectious diseases, and that this has severe economic consequences for the dairy industry and welfare implications. Here we present preliminary functional evidence showing that the innate immune response differs between cow breeds. The ability of macrophages (MØ) to kill pathogens depends in part on oxygen-dependent and independent mechanisms. The oxygen-dependent mechanisms rely on the generation of reactive oxygen and nitrogen species (ROS/RNS, respectively). ROS production has been shown to activate the inflammasome complex in MØ leading to increased production of the pro-inflammatory cytokine Interleukin-1β (IL-1β). Conversely RNS inhibits inflammasome mediated IL-1β activation, indicating a division between inflammasome activation and RNS production. In the present study MØ from Brown Swiss (BS) cattle produce significantly more RNS and less IL-1β when compared to cells from Holstein Friesian (HF) cattle in response to bacterial or fungal stimuli. Furthermore, BS MØ killed ingested Salmonella typhimurium more efficiently, supporting anecdotal evidence of increased disease resistance of the breed. Inhibition of autophagy by 3-methyladenine (3-MA) stimulated IL-1β secretion in cells from both breeds, but was more pronounced in HF MØ. Blocking RNS production by l-arginase completely abolished RNS production but increased IL-1β secretion in BS MØ. Collectively these preliminary data suggest that the dichotomy of inflammasome activation and RNS production exists in cattle and differs between these two breeds. As pattern recognition receptors and signaling pathways are involved in the assessed functional differences presented herein, our data potentially aid the identification of in vitro predictors of appropriate innate immune response. Finally, these predictors may assist in the discovery of candidate genes conferring increased disease resistance for future use in

  20. Tribbles 3 Inhibits Brown Adipocyte Differentiation and Function by Suppressing Insulin Signaling

    PubMed Central

    Jeong, Ha-Won; Choi, Ran Hee; McClellan, Jamie L.; Piroli, Gerardo G.; Frizzell, Norma; Tseng, Yu-Hua; Goodyear, Laurie J.; Koh, Ho-Jin

    2016-01-01

    Recent studies have demonstrated that adult humans have substantial amounts of functioning brown adipose tissue (BAT). Since BAT has been implicated as an anti-obese and anti-diabetic tissue, it is important to understand the signaling molecules that regulate BAT function. There has been a link between insulin signaling and BAT metabolism as deletion or pharmaceutical inhibition of insulin signaling impairs BAT differentiation and function. Tribbles 3 (TRB3) is a pseudo kinase that has been shown to regulate metabolism and insulin signaling in multiple tissues but the role of TRB3 in BAT has not been studied. In this study, we found that TRB3 expression was present in BAT and overexpression of TRB3 in brown preadipocytes impaired differentiation and decreased expression of BAT markers. Furthermore, TRB3 overexpression resulted in significantly lower oxygen consumption rates for basal and proton leakage, indicating decreased BAT activity. Based on previous studies showing that deletion or pharmaceutical inhibition of insulin signaling impairs BAT differentiation and function, we assessed insulin signaling in brown preadipocytes and BAT in vivo. Overexpression of TRB3 in cells impaired insulin-stimulated IRS1 and Akt phosphorylation, whereas TRB3KO mice displayed improved IRS1 and Akt phosphorylation. Finally, deletion of IRS1 abolished the function of TRB3 to regulate BAT differentiation and metabolism. These data demonstrate that TRB3 inhibits insulin signaling in BAT, resulting in impaired differentiation and function. PMID:26801556

  1. On the local fractional derivative of everywhere non-differentiable continuous functions on intervals

    NASA Astrophysics Data System (ADS)

    Liu, Cheng-shi

    2017-01-01

    We first prove that for a continuous function f(x) defined on an open interval, the Kolvankar-Gangal's (or equivalently Chen-Yan-Zhang's) local fractional derivative f(α)(x) is not continuous, and then prove that it is impossible that the KG derivative f(α)(x) exists everywhere on the interval and satisfies f(α)(x) ≠ 0 in the same time. In addition, we give a criterion of the nonexistence of the local fractional derivative of everywhere non-differentiable continuous functions. Furthermore, we construct two simple nowhere differentiable continuous functions on (0, 1) and prove that they have no the local fractional derivatives everywhere.

  2. On the representation of bicomplex pseudoanalytic functions by integro-differential operators

    NASA Astrophysics Data System (ADS)

    Berglez, Peter

    2016-06-01

    We consider a class of bicomplex pseudoanalytic functions which can be characterized by the generalized Bers-Vekua equation D w =c w * with c =γ-1(D γ ) where D represents the generalized Cauchy-Riemann operator of bicomplex analysis and γ a suitable solution of the differential equation DD*U - (n(n + 1)/(z + z*)2)U = 0, n ∈ ℕ. Using a particular Bäcklund transformation we succeed finding explicit representations for the solutions w by means of certain integro-differential operators. These operators act on bicomplex holomorphic functions. Some cases where the function γ is of particular form are investigated in detail.

  3. Detection of Gender-Based Differential Item Functioning in a Mathematics Performance Assessment.

    ERIC Educational Resources Information Center

    Wang, Ning; Lane, Suzanne

    This study used three different differential item functioning (DIF) procedures to examine the extent to which items in a mathematics performance assessment functioned differently for matched gender groups. In addition to examining the appropriateness of individual items in terms of DIF with respect to gender, an attempt was made to identify…

  4. Children with High-Functioning Autism and Asperger's Syndrome: Can We Differentiate Their Cognitive Profiles?

    ERIC Educational Resources Information Center

    Planche, Pascale; Lemonnier, Eric

    2012-01-01

    The aim of this study was to investigate whether children with high-functioning autism (HFA) and Asperger's syndrome (AS) can be differentiated from each other and from typically developing children on their cognitive profiles. The present study included a total of 45 participants: children with autism (high-functioning autism or Asperger's…

  5. A Class of Practically Nowhere Differentiable Functions on the Complex Plane

    ERIC Educational Resources Information Center

    Hetzel, Andrew J.

    2006-01-01

    This note could find classroom use in an introductory course on complex analysis. Using some of the most significant theorems from complex analysis, the main result provides a simple method for transforming many elementary functions (defined on the complex plane) into everywhere continuous functions that are differentiable only on a nowhere dense…

  6. Building Mathematical Maturity in Calculus: Teaching Implicit Differentiation through a Review of Functions

    ERIC Educational Resources Information Center

    Hare, Angela; Phillippy, Doug

    2004-01-01

    A program on calculus is conducted, which helps students learn about inherent differentiation through a study of mathematical functions, while simultaneously reinforcing their understanding of functional concepts. This process develops their mathematical experience in the field of calculus and in other advanced quantitative programs.

  7. Differential Item Functioning Analysis of the Mental, Emotional, and Bodily Toughness Inventory

    ERIC Educational Resources Information Center

    Gao, Yong; Mack, Mick G.; Ragan, Moira A.; Ragan, Brian

    2012-01-01

    In this study the authors used differential item functioning analysis to examine if there were items in the Mental, Emotional, and Bodily Toughness Inventory functioning differently across gender and athletic membership. A total of 444 male (56.3%) and female (43.7%) participants (30.9% athletes and 69.1% non-athletes) responded to the Mental,…

  8. Starches of varied digestibilities differentially modify intestinal function in rats.

    PubMed

    Lajvardi, A; Mazarin, G I; Gillespie, M B; Satchithanandam, S; Calvert, R J

    1993-12-01

    Starches of different digestibilities may enter the colon to different extents and alter colonic function. Male Fischer 344 rats were fed diets containing 25% cooked potato starch, arrowroot starch, high amylose cornstarch or raw potato starch for 6 wk. Fecal weight, transit time, colonic thymidine kinase activity (a marker for cell proliferation), and weight, starch content and pH of the cecum and proximal and distal colon were measured. Raw potato starch was much less completely digested than high amylose cornstarch, resulting in a 32-fold greater amount of undigested starch entering the cecum in the raw potato starch group. Both the high amylose cornstarch and raw potato starch diets significantly enhanced fecal weight and produced large intestinal hypertrophy, effects that were greatest in the raw potato starch group. Raw potato starch feeding was associated with the highest level of thymidine kinase activity, although the differences in thymidine kinase activity among the four groups were not significant. This diet also produced a 50% longer transit time. Entry of a large amount of raw potato starch into the colon resulted in greater luminal acidity, greater luminal bulk and slower transit. A much smaller amount of starch entered the colon in the high amylose cornstarch group and resulted in fecal bulking but no alteration in transit.

  9. Reviewing prescription spending and accessory usage.

    PubMed

    Oxenham, Julie

    This article aims to explore the role of the stoma nurse specialist in the community and how recent initiatives within the NHS have impacted on the roles in stoma care to react to the rising prescription costs in the specialty. The article will explore how the stoma care nurse conducted her prescription reviews within her own clinical commissioning group (CCG). The findings of the reviews will be highlighted by a small case history and a mini audit that reveals that some stoma patients may be using their stoma care accessories inappropriately, which may contribute to the rise in stoma prescription spending. To prevent the incorrect use of stoma appliances it may necessitate an annual review of ostomates (individuals who have a stoma), as the author's reviews revealed that inappropriate usage was particularly commonplace when a patient may have not been reviewed by a stoma care specialist for some considerable amount of time. Initial education of the ostomate and ongoing education of how stoma products work is essential to prevent the misuse of stoma appliances, particularly accessories, as the reviews revealed that often patients were not always aware of how their products worked in practice.

  10. Two Cases of an Epidermoid Cyst Developing in an Intrapancreatic Accessory Spleen Identified during Laparoscopic Distal Pancreatectomy

    PubMed Central

    Fujii, Masakuni; Yoshioka, Masao; Shiode, Junji

    2016-01-01

    Epidermoid cysts presenting within an intrapancreatic accessory spleen are rare non-neoplastic cysts typically occurring in the pancreatic tail. This entity is difficult to diagnose given there are many types of pancreatic neoplastic cysts. We herein describe two cases of an epidermoid cyst within an intrapancreatic accessory spleen for which we performed a resection by laparoscopic distal pancreatectomy. Epidermoid cysts in an intrapancreatic accessory spleen should therefore be considered in the differential diagnosis of pancreatic tail cystic lesions. Laparoscopic distal pancreatectomy can be a useful, minimally invasive surgical approach for treating these cysts as well as for the treatment of benign or low-grade malignant tumors located in the pancreatic body or tail. PMID:27803407

  11. Differential Light Chain Assembly Influences Outer Arm Dynein Motor Function

    PubMed Central

    DiBella, Linda M.; Gorbatyuk, Oksana; Sakato, Miho; Wakabayashi, Ken-ichi; Patel-King, Ramila S.; Pazour, Gregory J.; Witman, George B.; King, Stephen M.

    2005-01-01

    Tctex1 and Tctex2 were originally described as potential distorters/sterility factors in the non-Mendelian transmission of t-haplotypes in mice. These proteins have since been identified as subunits of cytoplasmic and/or axonemal dyneins. Within the Chlamydomonas flagellum, Tctex1 is a subunit of inner arm I1. We have now identified a second Tctex1-related protein (here termed LC9) in Chlamydomonas. LC9 copurifies with outer arm dynein in sucrose density gradients and is missing only in those strains completely lacking this motor. Zero-length cross-linking of purified outer arm dynein indicates that LC9 interacts directly with both the IC1 and IC2 intermediate chains. Immunoblot analysis revealed that LC2, LC6, and LC9 are missing in an IC2 mutant strain (oda6-r88) that can assemble outer arms but exhibits significantly reduced flagellar beat frequency. This defect is unlikely to be due to lack of LC6, because an LC6 null mutant (oda13) exhibits only a minor swimming abnormality. Using an LC2 null mutant (oda12-1), we find that although some outer arm dynein components assemble in the absence of LC2, they are nonfunctional. In contrast, dyneins from oda6-r88, which also lack LC2, retain some activity. Furthermore, we observed a synthetic assembly defect in an oda6-r88 oda12-1 double mutant. These data suggest that LC2, LC6, and LC9 have different roles in outer arm assembly and are required for wild-type motor function in the Chlamydomonas flagellum. PMID:16195342

  12. Differentiating emotional processing and attention in psychopathy with functional neuroimaging.

    PubMed

    Anderson, Nathaniel E; Steele, Vaughn R; Maurer, J Michael; Rao, Vikram; Koenigs, Michael R; Decety, Jean; Kosson, David S; Calhoun, Vince D; Kiehl, Kent A

    2017-01-16

    Individuals with psychopathy are often characterized by emotional processing deficits, and recent research has examined the specific contexts and cognitive mechanisms that underlie these abnormalities. Some evidence suggests that abnormal features of attention are fundamental to emotional deficits in persons with psychopathy, but few studies have demonstrated the neural underpinnings responsible for such effects. Here, we use functional neuroimaging to examine attention-emotion interactions among incarcerated individuals (n = 120) evaluated for psychopathic traits using the Hare Psychopathy Checklist-Revised (PCL-R). Using a task designed to manipulate attention to emotional features of visual stimuli, we demonstrate effects representing implicit emotional processing, explicit emotional processing, attention-facilitated emotional processing, and vigilance for emotional content. Results confirm the importance of considering mechanisms of attention when evaluating emotional processing differences related to psychopathic traits. The affective-interpersonal features of psychopathy (PCL-R Factor 1) were associated with relatively lower emotion-dependent augmentation of activity in visual processing areas during implicit emotional processing, while antisocial-lifestyle features (PCL-R Factor 2) were associated with elevated activity in the amygdala and related salience network regions. During explicit emotional processing, psychopathic traits were associated with upregulation in the medial prefrontal cortex, insula, and superior frontal regions. Isolating the impact of explicit attention to emotional content, only Factor 1 was related to upregulation of activity in the visual processing stream, which was accompanied by increased activity in the angular gyrus. These effects highlight some important mechanisms underlying abnormal features of attention and emotional processing that accompany psychopathic traits.

  13. Polarization of an electroactive functional film on titanium for inducing osteogenic differentiation

    PubMed Central

    Zhou, Zhengnan; Li, Weiping; He, Tianrui; Qian, Lei; Tan, Guoxin; Ning, Chengyun

    2016-01-01

    To enhance the surface bioactivity of titanium (Ti) prostheses, an electroactive polyvinylidene fluoride (PVDF) film was prepared on a Ti substrate to provide a mimetic of the electrical microenvironment, which facilitated the performance of cell functions. The results of cell proliferation and differentiation assays indicated that polarization of the PVDF-Ti (PTi) altered its surface charge, thus inducing adhesion, proliferation and osteogenic differentiation of cells. The polarized PVDF-Ti (PPTi) may therefore find applications in bone regeneration. PMID:27762318

  14. Polarization of an electroactive functional film on titanium for inducing osteogenic differentiation

    NASA Astrophysics Data System (ADS)

    Zhou, Zhengnan; Li, Weiping; He, Tianrui; Qian, Lei; Tan, Guoxin; Ning, Chengyun

    2016-10-01

    To enhance the surface bioactivity of titanium (Ti) prostheses, an electroactive polyvinylidene fluoride (PVDF) film was prepared on a Ti substrate to provide a mimetic of the electrical microenvironment, which facilitated the performance of cell functions. The results of cell proliferation and differentiation assays indicated that polarization of the PVDF-Ti (PTi) altered its surface charge, thus inducing adhesion, proliferation and osteogenic differentiation of cells. The polarized PVDF-Ti (PPTi) may therefore find applications in bone regeneration.

  15. Role of Protein Phosphatase 2A in Osteoblast Differentiation and Function

    PubMed Central

    Okamura, Hirohiko; Yoshida, Kaya; Morimoto, Hiroyuki; Teramachi, Jumpei; Ochiai, Kazuhiko; Haneji, Tatsuji; Yamamoto, Akihito

    2017-01-01

    The reversible phosphorylation of proteins plays hugely important roles in a variety of cellular processes, such as differentiation, proliferation, and apoptosis. These processes are strictly controlled by protein kinases (phosphorylation) and phosphatases (de-phosphorylation). Here we provide a brief history of the study of protein phosphorylation, including a summary of different types of protein kinases and phosphatases. One of the most physiologically important serine/threonine phosphatases is PP2A. This review provides a description of the phenotypes of various PP2A transgenic mice and further focuses on the known functions of PP2A in bone formation, including its role in osteoblast differentiation and function. A reduction in PP2A promotes bone formation and osteoblast differentiation through the regulation of bone-related transcription factors such as Osterix. Interestingly, downregulation of PP2A also stimulates adipocyte differentiation from undifferentiated mesenchymal cells under the appropriate adipogenic differentiation conditions. In osteoblasts, PP2A is also involved in the ability to control osteoclastogenesis as well as in the proliferation and metastasis of osteosarcoma cells. Thus, PP2A is considered to be a comprehensive factor in controlling the differentiation and function of cells derived from mesenchymal cells such as osteoblasts and adipocytes. PMID:28241467

  16. Sclerotic fibroma (storiform collagenoma)-like stroma in a fibroadenoma of axillary accessory breast tissue.

    PubMed

    Val-Bernal, José Fernando; González-Vela, María Carmen; De Grado, Mauricio; Garijo, María Francisca

    2012-08-01

    Accessory breast tissue is a subcutaneous remnant persisting after normal embryological development of the breast. It occurs most frequently in the axilla. Fibroadenomas in axillary breast tissue are rare. We report the case of a 29-year-old female patient who presented a fibroadenoma arising in the accessory breast tissue of the right axillary fossa. The neoplasm showed foci of sclerotic fibroma-like stroma. The patient had no signs of Cowden's syndrome. To the best of our knowledge, a lesion of this kind has not been previously reported. This stromal change suggests an uncommon involutional phase of the fibroadenoma with production of sclerotic and hypocellular collagen. The lesion should be differentiated from extraneural perineuroma, from the changes in fibroadenomas in Cowden's syndrome, from sclerosing lobular hyperplasia (fibroadenomatoid mastopathy) and from pseudoangiomatous stromal hyperplasia.

  17. 21 CFR 876.5820 - Hemodialysis system and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... conditions and that consists of an extracorporeal blood system, a conventional dialyzer, a dialysate delivery system, and accessories. Blood from a patient flows through the tubing of the extracorporeal blood system and accessories to the blood compartment of the dialyzer, then returns through further tubing of...

  18. 21 CFR 876.5820 - Hemodialysis system and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... conditions and that consists of an extracorporeal blood system, a conventional dialyzer, a dialysate delivery system, and accessories. Blood from a patient flows through the tubing of the extracorporeal blood system and accessories to the blood compartment of the dialyzer, then returns through further tubing of...

  19. 21 CFR 876.5820 - Hemodialysis system and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... conditions and that consists of an extracorporeal blood system, a conventional dialyzer, a dialysate delivery system, and accessories. Blood from a patient flows through the tubing of the extracorporeal blood system and accessories to the blood compartment of the dialyzer, then returns through further tubing of...

  20. 21 CFR 876.5820 - Hemodialysis system and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... conditions and that consists of an extracorporeal blood system, a conventional dialyzer, a dialysate delivery system, and accessories. Blood from a patient flows through the tubing of the extracorporeal blood system and accessories to the blood compartment of the dialyzer, then returns through further tubing of...

  1. 14 CFR 23.1192 - Engine accessory compartment diaphragm.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Engine accessory compartment diaphragm. 23... Powerplant Powerplant Fire Protection § 23.1192 Engine accessory compartment diaphragm. For aircooled radial engines, the engine power section and all portions of the exhaust sytem must be isolated from the...

  2. 14 CFR 125.149 - Engine accessory section diaphragm.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Engine accessory section diaphragm. 125.149... Requirements § 125.149 Engine accessory section diaphragm. Unless equivalent protection can be shown by other means, a diaphragm that complies with § 125.145 must be provided on air-cooled engines to isolate...

  3. 14 CFR 23.1192 - Engine accessory compartment diaphragm.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Engine accessory compartment diaphragm. 23... Powerplant Powerplant Fire Protection § 23.1192 Engine accessory compartment diaphragm. For aircooled radial engines, the engine power section and all portions of the exhaust sytem must be isolated from the...

  4. 14 CFR 125.149 - Engine accessory section diaphragm.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Engine accessory section diaphragm. 125.149... Requirements § 125.149 Engine accessory section diaphragm. Unless equivalent protection can be shown by other means, a diaphragm that complies with § 125.145 must be provided on air-cooled engines to isolate...

  5. 14 CFR 23.1437 - Accessories for multiengine airplanes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Accessories for multiengine airplanes. 23... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 23.1437 Accessories for multiengine airplanes. For multiengine...

  6. 14 CFR 23.1437 - Accessories for multiengine airplanes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Accessories for multiengine airplanes. 23... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 23.1437 Accessories for multiengine airplanes. For multiengine...

  7. 14 CFR 23.1192 - Engine accessory compartment diaphragm.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Engine accessory compartment diaphragm. 23... Powerplant Powerplant Fire Protection § 23.1192 Engine accessory compartment diaphragm. For aircooled radial engines, the engine power section and all portions of the exhaust sytem must be isolated from the...

  8. 14 CFR 125.149 - Engine accessory section diaphragm.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Engine accessory section diaphragm. 125.149... Requirements § 125.149 Engine accessory section diaphragm. Unless equivalent protection can be shown by other means, a diaphragm that complies with § 125.145 must be provided on air-cooled engines to isolate...

  9. 14 CFR 23.1192 - Engine accessory compartment diaphragm.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine accessory compartment diaphragm. 23... Powerplant Powerplant Fire Protection § 23.1192 Engine accessory compartment diaphragm. For aircooled radial engines, the engine power section and all portions of the exhaust sytem must be isolated from the...

  10. 14 CFR 125.149 - Engine accessory section diaphragm.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Engine accessory section diaphragm. 125.149... Requirements § 125.149 Engine accessory section diaphragm. Unless equivalent protection can be shown by other means, a diaphragm that complies with § 125.145 must be provided on air-cooled engines to isolate...

  11. 21 CFR 864.3600 - Microscopes and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Microscopes and accessories. 864.3600 Section 864.3600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Pathology Instrumentation and Accessories §...

  12. 21 CFR 884.2700 - Intrauterine pressure monitor and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Intrauterine pressure monitor and accessories. 884... Monitoring Devices § 884.2700 Intrauterine pressure monitor and accessories. (a) Identification. An intrauterine pressure monitor is a device designed to detect and measure intrauterine and amniotic...

  13. 21 CFR 884.2660 - Fetal ultrasonic monitor and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Fetal ultrasonic monitor and accessories. 884.2660... Devices § 884.2660 Fetal ultrasonic monitor and accessories. (a) Identification. A fetal ultrasonic monitor is a device designed to transmit and receive ultrasonic energy into and from the pregnant...

  14. 21 CFR 884.2660 - Fetal ultrasonic monitor and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Fetal ultrasonic monitor and accessories. 884.2660... Devices § 884.2660 Fetal ultrasonic monitor and accessories. (a) Identification. A fetal ultrasonic monitor is a device designed to transmit and receive ultrasonic energy into and from the pregnant...

  15. 49 CFR 192.147 - Flanges and flange accessories.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ....147 Flanges and flange accessories. (a) Each flange or flange accessory (other than cast iron) must... be subjected in service. (c) Each flange on a flanged joint in cast iron pipe must conform in dimensions, drilling, face and gasket design to ASME/ANSI B16.1 and be cast integrally with the pipe,...

  16. 46 CFR 98.25-40 - Valves, fittings, and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Anhydrous Ammonia in Bulk § 98.25-40 Valves, fittings, and accessories. (a) All valves, flanges, fittings and accessory equipment shall be of a type suitable for use with anhydrous ammonia and shall be made... Engineering) of this chapter. Valves shall be fitted with noncorrosive material suitable for ammonia...

  17. 46 CFR 98.25-40 - Valves, fittings, and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Anhydrous Ammonia in Bulk § 98.25-40 Valves, fittings, and accessories. (a) All valves, flanges, fittings and accessory equipment shall be of a type suitable for use with anhydrous ammonia and shall be made... Engineering) of this chapter. Valves shall be fitted with noncorrosive material suitable for ammonia...

  18. 46 CFR 98.25-40 - Valves, fittings, and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Anhydrous Ammonia in Bulk § 98.25-40 Valves, fittings, and accessories. (a) All valves, flanges, fittings and accessory equipment shall be of a type suitable for use with anhydrous ammonia and shall be made... Engineering) of this chapter. Valves shall be fitted with noncorrosive material suitable for ammonia...

  19. 46 CFR 98.25-40 - Valves, fittings, and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Anhydrous Ammonia in Bulk § 98.25-40 Valves, fittings, and accessories. (a) All valves, flanges, fittings and accessory equipment shall be of a type suitable for use with anhydrous ammonia and shall be made... Engineering) of this chapter. Valves shall be fitted with noncorrosive material suitable for ammonia...

  20. 46 CFR 98.25-40 - Valves, fittings, and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Anhydrous Ammonia in Bulk § 98.25-40 Valves, fittings, and accessories. (a) All valves, flanges, fittings and accessory equipment shall be of a type suitable for use with anhydrous ammonia and shall be made... Engineering) of this chapter. Valves shall be fitted with noncorrosive material suitable for ammonia...

  1. Differentially Private Synthesization of Multi-Dimensional Data using Copula Functions

    PubMed Central

    Li, Haoran; Xiong, Li; Jiang, Xiaoqian

    2014-01-01

    Differential privacy has recently emerged in private statistical data release as one of the strongest privacy guarantees. Most of the existing techniques that generate differentially private histograms or synthetic data only work well for single dimensional or low-dimensional histograms. They become problematic for high dimensional and large domain data due to increased perturbation error and computation complexity. In this paper, we propose DPCopula, a differentially private data synthesization technique using Copula functions for multi-dimensional data. The core of our method is to compute a differentially private copula function from which we can sample synthetic data. Copula functions are used to describe the dependence between multivariate random vectors and allow us to build the multivariate joint distribution using one-dimensional marginal distributions. We present two methods for estimating the parameters of the copula functions with differential privacy: maximum likelihood estimation and Kendall’s τ estimation. We present formal proofs for the privacy guarantee as well as the convergence property of our methods. Extensive experiments using both real datasets and synthetic datasets demonstrate that DPCopula generates highly accurate synthetic multi-dimensional data with significantly better utility than state-of-the-art techniques. PMID:25405241

  2. Computing the numerical solution to functional differential equations: some recent progresses towards E. Hopf's 1952 dream

    NASA Astrophysics Data System (ADS)

    Venturi, Daniele

    2016-11-01

    The fundamental importance of functional differential equations has been recognized in many areas of mathematical physics, such as fluid dynamics, quantum field theory and statistical physics. For example, in the context of fluid dynamics, the Hopf characteristic functional equation was deemed by Monin and Yaglom to be "the most compact formulation of the turbulence problem", which is the problem of determining the statistical properties of the velocity and pressure fields of Navier-Stokes equations given statistical information on the initial state. However, no effective numerical method has yet been developed to compute the solution to functional differential equations. In this talk I will provide a new perspective on this general problem, and discuss recent progresses in approximation theory for nonlinear functionals and functional equations. The proposed methods will be demonstrated through various examples.

  3. Multicopper manganese oxidase accessory proteins bind Cu and heme.

    PubMed

    Butterfield, Cristina N; Tao, Lizhi; Chacón, Kelly N; Spiro, Thomas G; Blackburn, Ninian J; Casey, William H; Britt, R David; Tebo, Bradley M

    2015-12-01

    Multicopper oxidases (MCOs) catalyze the oxidation of a diverse group of metal ions and organic substrates by successive single-electron transfers to O2 via four bound Cu ions. MnxG, which catalyzes MnO2 mineralization by oxidizing both Mn(II) and Mn(III), is unique among multicopper oxidases in that it carries out two energetically distinct electron transfers and is tightly bound to accessory proteins. There are two of these, MnxE and MnxF, both approximately 12kDa. Although their sequences are similar to those found in the genomes of several Mn-oxidizing Bacillus species, they are dissimilar to those of proteins with known function. Here, MnxE and MnxF are co-expressed independent of MnxG and are found to oligomerize into a higher order stoichiometry, likely a hexamer. They bind copper and heme, which have been characterized by electron paramagnetic resonance (EPR), X-ray absorption spectroscopy (XAS), and UV-visible (UV-vis) spectrophotometry. Cu is found in two distinct type 2 (T2) copper centers, one of which appears to be novel; heme is bound as a low-spin species, implying coordination by two axial ligands. MnxE and MnxF do not oxidize Mn in the absence of MnxG and are the first accessory proteins to be required by an MCO. This may indicate that Cu and heme play roles in electron transfer and/or Cu trafficking.

  4. Novel function of the retinoblastoma protein in fat: regulation of white versus brown adipocyte differentiation.

    PubMed

    Hansen, Jacob B; te Riele, Hein; Kristiansen, Karsten

    2004-06-01

    The differentiation of white and brown fat cells is controlled by a similar set of transcription factors, including PPARgamma and C/EBPalpha. However, despite many similarities between the two types of fat cells, they carry out essentially opposite functions in vivo, with white adipocytes being the major energy store and brown adipocytes being potent energy-dissipaters through thermogenesis. Yet, little is known about factors differentially regulating the formation of white and brown fat cells. Members of the retinoblastoma protein family (pRB, p107, p130) have been implicated in the regulation of adipocyte differentiation, and expression and phosphorylation of the three retinoblastoma family proteins oscillate in a characteristic manner during differentiation of the white preadipocyte cell line 3T3-L1. We have recently demonstrated a surprising function of the retinoblastoma protein in the regulation of white versus brown adipocyte differentiation in vitro and possibly in vivo. Here we summarize the current knowledge on the retinoblastoma protein in fat cells, with particular emphasis on its potential role in adipocyte lineage commitment and differentiation.

  5. Human embryonic stem cells differentiate into functional renal proximal tubular-like cells.

    PubMed

    Narayanan, Karthikeyan; Schumacher, Karl M; Tasnim, Farah; Kandasamy, Karthikeyan; Schumacher, Annegret; Ni, Ming; Gao, Shujun; Gopalan, Began; Zink, Daniele; Ying, Jackie Y

    2013-04-01

    Renal cells are used in basic research, disease models, tissue engineering, drug screening, and in vitro toxicology. In order to provide a reliable source of human renal cells, we developed a protocol for the differentiation of human embryonic stem cells into renal epithelial cells. The differentiated stem cells expressed markers characteristic of renal proximal tubular cells and their precursors, whereas markers of other renal cell types were not expressed or expressed at low levels. Marker expression patterns of these differentiated stem cells and in vitro cultivated primary human renal proximal tubular cells were comparable. The differentiated stem cells showed morphological and functional characteristics of renal proximal tubular cells, and generated tubular structures in vitro and in vivo. In addition, the differentiated stem cells contributed in organ cultures for the formation of simple epithelia in the kidney cortex. Bioreactor experiments showed that these cells retained their functional characteristics under conditions as applied in bioartificial kidneys. Thus, our results show that human embryonic stem cells can differentiate into renal proximal tubular-like cells. Our approach would provide a source for human renal proximal tubular cells that are not affected by problems associated with immortalized cell lines or primary cells.

  6. Intrapancreatic accessory spleen diagnosed on radionuclide imaging.

    PubMed

    Belkhir, Sara Melboucy; Archambaud, Frédérique; Prigent, Alain; Chaumet-Riffaud, Philippe

    2009-09-01

    Intrapancreatic accessory spleen (IPAS) is ectopic splenic tissue distinct from the main spleen. A 46-year-old man with chronic hepatitis C, presented in 2006 with low right chest pain which led to a diagnosis of tuberculosis pleurisy. CT scan and MRI showed a round, homogenous, well limited mass of 3cm in the pancreas tail. Tc-99m heat-damaged red blood cell scintigraphy with SPECT-CT was performed to confirm the diagnosis of IPAS. Most cases of IPAS described in the literature were diagnosed by pathologists after distal pancreatectomy and splenectomy performed for a suspicion of pancreatic tumor. However, heat-damaged red blood cell scintigraphy remains the most commonly used diagnostic procedure for IPAS, even if superparamagnetic iron oxide MRI contrast agent may be used in the future.

  7. Fluid assisted installation of electrical cable accessories

    DOEpatents

    Mayer, Robert W.; Silva, Frank A.

    1977-01-01

    An electrical cable accessory includes a generally tubular member of elastomeric material which is to be installed by placement over a cylindrical surface to grip the cylindrical surface, when in appropriate assembled relation therewith, with a predetermined gripping force established by dilation of the tubular member, the installation being facilitated by introducing fluid under pressure, through means provided in the tubular member, between the tubular member and the cylindrical surface, and simultaneously impeding the escape of the fluid under pressure from between the tubular member and the cylindrical surface by means adjacent one of the ends of the tubular member to cause dilation of the tubular member and establish a fluid layer between the tubular member and the cylindrical surface, thereby reducing the gripping force during installation.

  8. /sup 99m/Tc-glucoheptonate for quantitation of differential renal function

    SciTech Connect

    Ziessman, H.A.; Balseiro, J.; Fahey, F.H.; Le, T.V.; Dubiansky, V.

    1987-05-01

    Differential renal function was calculated by using /sup 99m/Tc-glucoheptonate (Tc-GH) in 51 patients. Computer-acquired background-corrected individual renal function was calculated by using both the 1-3-min uptake counts and the 2-4-hr delayed static counts. The degree of correlation between the two was high (r = .96). An equally high correlation was noted in 16 children who were 12 years old or younger, in 15 patients with renal size disparity greater than 60/40%, and in six patients with abnormal creatinine clearances. Ten patients had a 30-min dynamic /sup 99m/Tc-DTPA study followed immediately by the injection of Tc-GH and acquisition of delayed static images 2-4 hr later. A high degree of correlation (r = .99) was seen between the 1-3-min differential function obtained by using Tc-DTPA and the 2-4-hr delayed differential function obtained by using Tc-GH. This study shows that Tc-GH is a clinically useful and valid tool for calculation of differential renal function and that Tc-GH combines many of the best aspects of Tc-DTPA and Tc-DMSA.

  9. Dendritic cells are accessory cells for the development of anti- trinitrophenyl cytotoxic T lymphocytes

    PubMed Central

    1980-01-01

    This study establishes that dendritic cells (DC) are the critical accessory cells for the development of anti-trinitrophenol (TNP) cytotoxic T lymphocytes (CTL) in vitro. We developed a model in which nylon wool-nonadherent spleen cells were used both as the responding and stimulating cells, the latter having been TNP-modified and x- irradiated. Thy-1-bearing CTL developed in C57BL/6, B6D2F1, and CBA mice only when small numbers of DC were added. Maximal responses in 5-d cultures were achieved with 0.5-1 DC/100 responding T cells. The DC did not have to be TNP modified directly. Anti-Ia and complement inactivated accessory cells, whereas similar treatment of the responders had no effect. DC exposed to ultraviolet radiation were ineffective, but x-irradiated DC were fully active. Culture media from DC, or from DC-nylon wool-passed spleen T cell cocultures that contained abundant CTL, would not substitute for viable DC. Enriched preparations of macrophages (M phi) were obtained from blood, peritoneal cavity, and spleens of BCG-immune and unprimed mice. M phi added at doses of 0.2-4% were weak or inactive as accessory cells. The level of Ia antigens on test M phi populations was quantitated and visualized by binding of a radioiodinated monoclonal anti-I-Ab,d antibody, clone B-21. M phi that bore substantial amounts of Ia from all organs were weak accessory cells. Addition of M phi to DC-T cell cocultures produced inhibitory effects, usually at a dose of 2% M phi. In contrast, 0.5% Ia-bearing M phi from BCG-immune boosted mice inhibited > 80% of the DC-mediated CTL response. Addition of indomethacin reversed M phi inhibition, and 10(-9) M prostaglandin E2 in turn blocked the indomethacin effect. Indomethacin also restored a low level of accessory cell function in immune-boosted adherent peritoneal cells, but not in preparations of monocytes and spleen M phi. Small numbers of DC were identified in preparations of immune- boosted peritoneal cells and may have accounted

  10. Kinetin Improves Barrier Function of the Skin by Modulating Keratinocyte Differentiation Markers

    PubMed Central

    An, Sungkwan; Cha, Hwa Jun; Ko, Jung-Min; Han, Hyunjoo; Kim, Su Young; Kim, Kyung-Suk; Lee, Song Jeong; An, In-Sook; Kim, Sangwon; Youn, Hae Jeong

    2017-01-01

    Background Kinetin is a plant hormone that regulates growth and differentiation. Keratinocytes, the basic building blocks of the epidermis, function in maintaining the skin barrier. Objective We examined whether kinetin induces skin barrier functions in vitro and in vivo. Methods To evaluate the efficacy of kinetin at the cellular level, expression of keratinocyte differentiation markers was assessed. Moreover, we examined the clinical efficacy of kinetin by evaluating skin moisture, transepidermal water loss (TEWL), and skin surface roughness in patients who used kinetin-containing cream. We performed quantitative real-time polymerase chain reaction to measure the expression of keratinocyte differentiation markers in HaCaT cells following treatment. A clinical trial was performed to assess skin moisture, TEWL, and evenness of skin texture in subjects who used kinetin-containing cream for 4 weeks. Results Kinetin increased involucrin, and keratin 1 mRNA in HaCaT cells. Moreover, use of a kinetin-containing cream improved skin moisture and TEWL while decreasing roughness of skin texture. Conclusion Kinetin induced the expression of keratinocyte differentiation markers, suggesting that it may affect differentiation to improve skin moisture content, TEWL, and other signs of skin aging. Therefore, kinetin is a potential new component for use in cosmetics as an anti-aging agent that improves the barrier function of skin. PMID:28223740

  11. The subcellular distribution and function of MTA1 in cancer differentiation.

    PubMed

    Liu, Jian; Xu, Dongkui; Wang, Haijuan; Zhang, Ying; Chang, Yanan; Zhang, Jinlong; Wang, Jia; Li, Chunxiao; Liu, Huan; Zhao, Mei; Lin, Chen; Zhan, Qimin; Huang, Changzhi; Qian, Haili

    2014-07-15

    The functions and mechanisms of metastasis-associated protein 1 (MTA1) in cancer progression are still unclear due to a lagged recognition of the subcellular localization. In the present study, using multiple molecular technologies we confirmed for the first time that MTA1 localizes to the nucleus, cytoplasm and nuclear envelope. MTA1 is primarily localized in the nucleus of normal adult tissues but in the cytoplasm of embryonic tissues. While in colon cancer, both distributions have been described. Further investigation revealed that MTA1 localizes on the nuclear envelope in a translocated promoter region (TPR)-dependent manner, while in the cytoplasm, MTA1 shows an obvious localization on microtubules. Both nuclear and cytoplasmic MTA1 are associated with cancer progression. However, these functions may be associated with different mechanisms because only nuclear MTA1 has been associated with cancer differentiation. Overexpression of MTA1 in HCT116 cells inhibited differentiation and promoted proliferation, whereas MTA1 knockdown resulted in cell differentiation and death. Theses results not only suggest that nuclear MTA1 is a good marker for cancer differentiation diagnosis and a potential target for the treatment of cancers but also reveal the necessity to differentially examine the functions of nuclear and cytoplasmic MTA1.

  12. Evolution of the continental crust as recorded in accessory minerals

    NASA Astrophysics Data System (ADS)

    Iizuka, Tsuyoshi

    2013-04-01

    Recent developments in precise in situ isotopic analysis by LA-ICPMS and SIMS allow correlating multiple isotopic systems within single grains of accessory minerals such as zircon and monazite. The combined isotope systematics have provided valuable insights into the evolution of the continental crust. Zircon, a common accessory phase in granitoids, can be precisely dated by the U-Pb system. Zircon Lu-Hf isotopic composition is a function of crustal residence time of the magmatic protolith, whereas the O isotopic composition is a sensitive record of reworking of mature sediments such as pelite. An integration of U-Pb, Lu-Hf and O isotopic data for detrital zircons from modern large rivers indicates that: (1) the preserved continental crust dominantly formed between 3.6 and 1.0 Ga, (2) the major mode of crustal development would change during the supercontinent cycle, i.e., the generation of juvenile crust during supercontinent fragmentation versus the stabilization of the generated crust via crustal remelting during supercontinent fragmentation, and (3) reworking of mature sediments increased abruptly at ca. 2.1 Ga. No granitoids are known to have survived since 4.03 Ga. Yet evidence of an even older evolved crust is provided by detrital zircons with ages up to 4.4 Ga from Mt. Narryer and Jack Hills metasedimentary rocks in the Yilgarn Craton, Western Australia. Recently, such Hadean zircons have been found from outside the Yilgarn Craton, indicating that the young Earth had widespread granitoid crust. In addition, another accessory phase, monazite, in the Mt. Narryer and Jack Hills metasedimentary rocks offers an unique opportunity to advance our knowledge of early crustal evolution. Monazite, a light rare earth element phosphate mineral, occurs as an igneous accessory phase particularly in low-Ca granitoids, in contrast to the occurrence of igneous zircon in a wide range of granitoids. U-Pb and Sm-Nd isotope systematic of monazite are analogous to U-Pb and Lu

  13. Osteogenic Differentiation of MSC through Calcium Signaling Activation: Transcriptomics and Functional Analysis

    PubMed Central

    Viti, Federica; Landini, Martina; Mezzelani, Alessandra; Petecchia, Loredana; Milanesi, Luciano; Scaglione, Silvia

    2016-01-01

    The culture of progenitor mesenchymal stem cells (MSC) onto osteoconductive materials to induce a proper osteogenic differentiation and mineralized matrix regeneration represents a promising and widely diffused experimental approach for tissue-engineering (TE) applications in orthopaedics. Among modern biomaterials, calcium phosphates represent the best bone substitutes, due to their chemical features emulating the mineral phase of bone tissue. Although many studies on stem cells differentiation mechanisms have been performed involving calcium-based scaffolds, results often focus on highlighting production of in vitro bone matrix markers and in vivo tissue ingrowth, while information related to the biomolecular mechanisms involved in the early cellular calcium-mediated differentiation is not well elucidated yet. Genetic programs for osteogenesis have been just partially deciphered, and the description of the different molecules and pathways operative in these differentiations is far from complete, as well as the activity of calcium in this process. The present work aims to shed light on the involvement of extracellular calcium in MSC differentiation: a better understanding of the early stage osteogenic differentiation program of MSC seeded on calcium-based biomaterials is required in order to develop optimal strategies to promote osteogenesis through the use of new generation osteoconductive scaffolds. A wide spectrum of analysis has been performed on time-dependent series: gene expression profiles are obtained from samples (MSC seeded on calcium-based scaffolds), together with related microRNAs expression and in vivo functional validation. On this basis, and relying on literature knowledge, hypotheses are made on the biomolecular players activated by the biomaterial calcium-phosphate component. Interestingly, a key role of miR-138 was highlighted, whose inhibition markedly increases osteogenic differentiation in vitro and enhance ectopic bone formation in vivo

  14. Global series solutions of nonlinear differential equations with shocks using Walsh functions

    NASA Astrophysics Data System (ADS)

    Gnoffo, Peter A.

    2014-02-01

    An orthonormal basis set composed of Walsh functions is used for deriving global solutions (valid over the entire domain) to nonlinear differential equations that include discontinuities. Function gn(x) of the set, a scaled Walsh function in sequency order, is comprised of n piecewise constant values (square waves) across the domain xa⩽x⩽xb. Only two square wave lengths are allowed in any function and a new derivation of the basis functions applies a fractal-like algorithm (infinitely self-similar) focused on the distribution of wave lengths. This distribution is determined by a recursive folding algorithm that propagates fundamental symmetries to successive values of n. Functions, including those with discontinuities, may be represented on the domain as a series in gn(x) with no occurrence of a Gibbs phenomenon (ringing) across the discontinuity. A much more powerful, self-mapping characteristic of the series is closure under multiplication - the product of any two Walsh functions is also a Walsh function. This self-mapping characteristic transforms the solution of nonlinear differential equations to the solution of systems of polynomial equations if the original nonlinearities can be represented as products of the dependent variables and the convergence of the series for n→∞ can be demonstrated. Fundamental operations (reciprocal, integral, derivative) on Walsh function series representations of functions with discontinuities are defined. Examples are presented for solution of the time dependent Burger's equation and for quasi-one-dimensional nozzle flow including a shock.

  15. Evaluation of Two Types of Differential Item Functioning in Factor Mixture Models with Binary Outcomes

    ERIC Educational Resources Information Center

    Lee, HwaYoung; Beretvas, S. Natasha

    2014-01-01

    Conventional differential item functioning (DIF) detection methods (e.g., the Mantel-Haenszel test) can be used to detect DIF only across observed groups, such as gender or ethnicity. However, research has found that DIF is not typically fully explained by an observed variable. True sources of DIF may include unobserved, latent variables, such as…

  16. Estimating the Importance of Differential Item Functioning. Program Statistics Research Technical Report No. 95-3.

    ERIC Educational Resources Information Center

    Rudas, Tamas; Zwick, Rebecca

    A method is proposed to assess the importance of differential item functioning (DIF) by estimating the largest possible fraction of the population in which DIF does not occur, or equivalently, the smallest possible portion of the population in which DIF may occur. The approach is based on latent class (C. C. Clogg, 1981) or mixture concepts, and…

  17. Gender-Related Differential Item Functioning on a Middle-School Mathematics Performance Assessment.

    ERIC Educational Resources Information Center

    Lane, Suzanne; And Others

    This study examined gender-related differential item functioning (DIF) using a mathematics performance assessment, the QUASAR Cognitive Assessment Instrument (QCAI), administered to middle school students. The QCAI was developed for the Quantitative Understanding: Amplifying Student Achievement and Reading (QUASAR) project, which focuses on…

  18. A Robust Outlier Approach to Prevent Type I Error Inflation in Differential Item Functioning

    ERIC Educational Resources Information Center

    Magis, David; De Boeck, Paul

    2012-01-01

    The identification of differential item functioning (DIF) is often performed by means of statistical approaches that consider the raw scores as proxies for the ability trait level. One of the most popular approaches, the Mantel-Haenszel (MH) method, belongs to this category. However, replacing the ability level by the simple raw score is a source…

  19. Power and Sample Size Calculations for Logistic Regression Tests for Differential Item Functioning

    ERIC Educational Resources Information Center

    Li, Zhushan

    2014-01-01

    Logistic regression is a popular method for detecting uniform and nonuniform differential item functioning (DIF) effects. Theoretical formulas for the power and sample size calculations are derived for likelihood ratio tests and Wald tests based on the asymptotic distribution of the maximum likelihood estimators for the logistic regression model.…

  20. The Effect of Differential Item Functioning in Anchor Items on Population Invariance of Equating

    ERIC Educational Resources Information Center

    Huggins, Anne Corinne

    2014-01-01

    Invariant relationships in the internal mechanisms of estimating achievement scores on educational tests serve as the basis for concluding that a particular test is fair with respect to statistical bias concerns. Equating invariance and differential item functioning are both concerned with invariant relationships yet are treated separately in the…

  1. Detecting Differential Item Functioning of a Course Satisfaction Instrument in the Presence of Multilevel Data

    ERIC Educational Resources Information Center

    Finch, Holmes; French, Brian

    2010-01-01

    The purposes of this study were to test for uniform differential item functioning (DIF) between male and female students on end-of-semester class evaluations in an introductory university science course and to demonstrate DIF detection methods that take into account the complex sampling mechanism that often underlies data used in such assessments.…

  2. Identification of Differential Item Functioning in Multiple-Group Settings: A Multivariate Outlier Detection Approach

    ERIC Educational Resources Information Center

    Magis, David; De Boeck, Paul

    2011-01-01

    We focus on the identification of differential item functioning (DIF) when more than two groups of examinees are considered. We propose to consider items as elements of a multivariate space, where DIF items are outlying elements. Following this approach, the situation of multiple groups is a quite natural case. A robust statistics technique is…

  3. Differential Item Functioning Detection across Two Methods of Defining Group Comparisons: Pairwise and Composite Group Comparisons

    ERIC Educational Resources Information Center

    Sari, Halil Ibrahim; Huggins, Anne Corinne

    2015-01-01

    This study compares two methods of defining groups for the detection of differential item functioning (DIF): (a) pairwise comparisons and (b) composite group comparisons. We aim to emphasize and empirically support the notion that the choice of pairwise versus composite group definitions in DIF is a reflection of how one defines fairness in DIF…

  4. Examining Type I Error and Power for Detection of Differential Item and Testlet Functioning

    ERIC Educational Resources Information Center

    Lee, Young-Sun; Cohen, Allan; Toro, Maritsa

    2009-01-01

    In this study, the effectiveness of detection of differential item functioning (DIF) and testlet DIF using SIBTEST and Poly-SIBTEST were examined in tests composed of testlets. An example using data from a reading comprehension test showed that results from SIBTEST and Poly-SIBTEST were not completely consistent in the detection of DIF and testlet…

  5. Differentiation of Cognitive Abilities as a Function of Neuroticism Level: A Measurement Equivalence/Invariance Analysis

    ERIC Educational Resources Information Center

    Bonaccio, Silvia; Reeve, Charlie L.

    2006-01-01

    This paper investigates the differentiation of cognitive abilities as a function of neuroticism. Specifically, we examine Eysenck and White's [Eysenck, H. J., and White, P. O. (1964). Personality and the measurement of intelligence. British Journal of Educational Psychology, 24, 197-201.] hypothesis that cognitive abilities are less differentiated…

  6. The differentiation and protective function of cytolytic CD4 T cells in influenza infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    CD4 T cells that recognize peptide antigen in the context of Class II MHC can differentiate into various subsets that are characterized by their helper functions. However, increasing evidence indicates that CD4 cells with direct cytolytic activity play a role in chronic, as well as, acute infections...

  7. Oscillation of certain higher-order neutral partial functional differential equations.

    PubMed

    Li, Wei Nian; Sheng, Weihong

    2016-01-01

    In this paper, we study the oscillation of certain higher-order neutral partial functional differential equations with the Robin boundary conditions. Some oscillation criteria are established. Two examples are given to illustrate the main results in the end of this paper.

  8. Effect Size Measures for Differential Item Functioning in a Multidimensional IRT Model

    ERIC Educational Resources Information Center

    Suh, Youngsuk

    2016-01-01

    This study adapted an effect size measure used for studying differential item functioning (DIF) in unidimensional tests and extended the measure to multidimensional tests. Two effect size measures were considered in a multidimensional item response theory model: signed weighted P-difference and unsigned weighted P-difference. The performance of…

  9. Item Purification in Differential Item Functioning Using Generalized Linear Mixed Models

    ERIC Educational Resources Information Center

    Liu, Qian

    2011-01-01

    For this dissertation, four item purification procedures were implemented onto the generalized linear mixed model for differential item functioning (DIF) analysis, and the performance of these item purification procedures was investigated through a series of simulations. Among the four procedures, forward and generalized linear mixed model (GLMM)…

  10. Identifying Differential Item Functioning in Multi-Stage Computer Adaptive Testing

    ERIC Educational Resources Information Center

    Gierl, Mark J.; Lai, Hollis; Li, Johnson

    2013-01-01

    The purpose of this study is to evaluate the performance of CATSIB (Computer Adaptive Testing-Simultaneous Item Bias Test) for detecting differential item functioning (DIF) when items in the matching and studied subtest are administered adaptively in the context of a realistic multi-stage adaptive test (MST). MST was simulated using a 4-item…

  11. Existence and exponential stability for impulsive stochastic partial functional differential equations

    NASA Astrophysics Data System (ADS)

    Xiao, Shuiming; Chen, Huabin

    2017-03-01

    In this paper, the existence and uniqueness, the exponential stability, and the almost sure exponential stability of mild solution for impulsive stochastic partial functional differential equations with finite delay are considered. Some sufficient conditions are established for our concerned problems, and some existing results are generalized and improved. Finally, an illustrative example is provided to show the feasibility and effectiveness of the obtained results.

  12. An Examination of Differential Item Functioning on the Vanderbilt Assessment of Leadership in Education

    ERIC Educational Resources Information Center

    Polikoff, Morgan S.; May, Henry; Porter, Andrew C.; Elliott, Stephen N.; Goldring, Ellen; Murphy, Joseph

    2009-01-01

    The Vanderbilt Assessment of Leadership in Education is a 360-degree assessment of the effectiveness of principals' learning-centered leadership behaviors. In this report, we present results from a differential item functioning (DIF) study of the assessment. Using data from a national field trial, we searched for evidence of DIF on school level,…

  13. Differential Item Functioning Analysis of the 2003-04 NHANES Physical Activity Questionnaire

    ERIC Educational Resources Information Center

    Gao, Yong; Zhu, Weimo

    2011-01-01

    Using differential item functioning (DIF) analyses, this study examined whether there were any DIF items in the National Health and Nutrition Examination Survey (NHANES) physical activity (PA) questionnaire. A subset of adult data from the 2003-04 NHANES study (n = 3,083) was used. PA items related to respondents' occupational, transportation,…

  14. Detecting Differential Item Functioning of Polytomous Items for an Ideal Point Response Process

    ERIC Educational Resources Information Center

    Wang, Wei; Tay, Louis; Drasgow, Fritz

    2013-01-01

    There has been growing use of ideal point models to develop scales measuring important psychological constructs. For meaningful comparisons across groups, it is important to identify items on such scales that exhibit differential item functioning (DIF). In this study, the authors examined several methods for assessing DIF on polytomous items…

  15. Assessing the Item Response Theory with Covariate (IRT-C) Procedure for Ascertaining Differential Item Functioning

    ERIC Educational Resources Information Center

    Tay, Louis; Vermunt, Jeroen K.; Wang, Chun

    2013-01-01

    We evaluate the item response theory with covariates (IRT-C) procedure for assessing differential item functioning (DIF) without preknowledge of anchor items (Tay, Newman, & Vermunt, 2011). This procedure begins with a fully constrained baseline model, and candidate items are tested for uniform and/or nonuniform DIF using the Wald statistic.…

  16. Investigating Gender Differential Item Functioning across Countries and Test Languages for PISA Science Items

    ERIC Educational Resources Information Center

    Le, Luc T.

    2009-01-01

    This study uses PISA cycle 3 field trial data to investigate the relationships between gender differential item functioning (DIF) across countries and test languages for science items and their formats and the four other dimensions defined in PISA framework: focus, context, competency, and scientific knowledge. The data used were collected from 60…

  17. Group-Specific Effects of Matching Subtest Contamination on the Identification of Differential Item Functioning

    ERIC Educational Resources Information Center

    Keiffer, Elizabeth Ann

    2011-01-01

    A differential item functioning (DIF) simulation study was conducted to explore the type and level of impact that contamination had on type I error and power rates in DIF analyses when the suspect item favored the same or opposite group as the DIF items in the matching subtest. Type I error and power rates were displayed separately for the…

  18. Differential Reinforcement as Treatment for Behavior Disorders: Procedural and Functional Variations.

    ERIC Educational Resources Information Center

    Vollmer, Timothy R.; Iwata, Brian A.

    1992-01-01

    This paper reviews the functional properties and procedural variations of differential reinforcement for the reduction of behavior disorders in individuals with developmental disabilities. The paper proposes that limited success may be a result of the arbitrary relationship that exists between reinforcers and target behaviors when behavioral…

  19. A Comparison of Four Differential Item Functioning Procedures in the Presence of Multidimensionality

    ERIC Educational Resources Information Center

    Bastug, Özlem Yesim Özbek

    2016-01-01

    Differential item functioning (DIF), or item bias, is a relatively new concept. It has been one of the most controversial and the most studied subject in measurement theory. DIF occurs when people who have the same ability level but from different groups have a different probability of a correct response. According to Item Response Theory (IRT),…

  20. Detection of Differential Item Functioning for More than Two Groups: A Monte Carlo Comparison of Methods

    ERIC Educational Resources Information Center

    Finch, W. Holmes

    2016-01-01

    Differential item functioning (DIF) assessment is a crucial component in test construction, serving as the primary way in which instrument developers ensure that measures perform in the same way for multiple groups within the population. When such is not the case, scores may not accurately reflect the trait of interest for all individuals in the…

  1. An Introduction to Missing Data in the Context of Differential Item Functioning

    ERIC Educational Resources Information Center

    Banks, Kathleen

    2015-01-01

    This article introduces practitioners and researchers to the topic of missing data in the context of differential item functioning (DIF), reviews the current literature on the issue, discusses implications of the review, and offers suggestions for future research. A total of nine studies were reviewed. All of these studies determined what effect…

  2. Studying Differential Item Functioning via Latent Variable Modeling: A Note on a Multiple-Testing Procedure

    ERIC Educational Resources Information Center

    Raykov, Tenko; Marcoulides, George A.; Lee, Chun-Lung; Chang, Chi

    2013-01-01

    This note is concerned with a latent variable modeling approach for the study of differential item functioning in a multigroup setting. A multiple-testing procedure that can be used to evaluate group differences in response probabilities on individual items is discussed. The method is readily employed when the aim is also to locate possible…

  3. Detecting Native Language Group Differences at the Subskills Level of Reading: A Differential Skill Functioning Approach

    ERIC Educational Resources Information Center

    Li, Hongli; Suen, Hoi K.

    2013-01-01

    Differential skill functioning (DSF) exists when examinees from different groups have different probabilities of successful performance in a certain subskill underlying the measured construct, given that they have the same ability on the overall construct. Using a DSF approach, this study examined the differences between two native language…

  4. Evaluation of Model Selection Strategies for Cross-Level Two-Way Differential Item Functioning Analysis

    ERIC Educational Resources Information Center

    Patarapichayatham, Chalie; Kamata, Akihito; Kanjanawasee, Sirichai

    2012-01-01

    Model specification issues on the cross-level two-way differential item functioning model were previously investigated by Patarapichayatham et al. (2009). Their study clarified that an incorrect model specification can easily lead to biased estimates of key parameters. The objective of this article is to provide further insights on the issue by…

  5. Parent Ratings of ADHD Symptoms: Differential Symptom Functioning across Malaysian Malay and Chinese Children

    ERIC Educational Resources Information Center

    Gomez, Rapson; Vance, Alasdair

    2008-01-01

    This study examined differential symptom functioning (DSF) in ADHD symptoms across Malay and Chinese children in Malaysia. Malay (N = 571) and Chinese (N = 254) parents completed the Disruptive Behavior Rating Scale, which lists the DSM-IV ADHD symptoms. DSF was examined using the multiple indicators multiple causes (MIMIC) structural equation…

  6. A Comparison of Two Area Measures for Detecting Differential Item Functioning.

    ERIC Educational Resources Information Center

    Kim, Seock-Ho; Cohen, Allan S.

    1991-01-01

    The exact and closed-interval area measures for detecting differential item functioning are compared for actual data from 1,000 African-American and 1,000 white college students taking a vocabulary test with items intentionally constructed to favor 1 set of examinees. No real differences in detection of biased items were found. (SLD)

  7. The Impact of Missing Data on the Detection of Nonuniform Differential Item Functioning

    ERIC Educational Resources Information Center

    Finch, W. Holmes

    2011-01-01

    Missing information is a ubiquitous aspect of data analysis, including responses to items on cognitive and affective instruments. Although the broader statistical literature describes missing data methods, relatively little work has focused on this issue in the context of differential item functioning (DIF) detection. Such prior research has…

  8. Numerical solutions of a control problem governed by functional differential equations

    NASA Technical Reports Server (NTRS)

    Banks, H. T.; Thrift, P. R.; Burns, J. A.; Cliff, E. M.

    1978-01-01

    A numerical procedure is proposed for solving optimal control problems governed by linear retarded functional differential equations. The procedure is based on the idea of 'averaging approximations', due to Banks and Burns (1975). For illustration, numerical results generated on an IBM 370/158 computer, which demonstrate the rapid convergence of the method are presented.

  9. Assessment of Differential Item Functioning under Cognitive Diagnosis Models: The DINA Model Example

    ERIC Educational Resources Information Center

    Li, Xiaomin; Wang, Wen-Chung

    2015-01-01

    The assessment of differential item functioning (DIF) is routinely conducted to ensure test fairness and validity. Although many DIF assessment methods have been developed in the context of classical test theory and item response theory, they are not applicable for cognitive diagnosis models (CDMs), as the underlying latent attributes of CDMs are…

  10. Cauchy problem and Green's functions for first order differential operators and algebraic quantization

    SciTech Connect

    Muehlhoff, Rainer

    2011-02-15

    Existence and uniqueness of advanced and retarded fundamental solutions (Green's functions) and of global solutions to the Cauchy problem is proved for a general class of first order linear differential operators on vector bundles over globally hyperbolic Lorentzian manifolds. This is a core ingredient to CAR-/CCR-algebraic constructions of quantum field theories on curved spacetimes, particularly for higher spin field equations.

  11. Differential Item Functioning (DIF) among Spanish-Speaking English Language Learners (ELLs) in State Science Tests

    ERIC Educational Resources Information Center

    Ilich, Maria O.

    2013-01-01

    Psychometricians and test developers evaluate standardized tests for potential bias against groups of test-takers by using differential item functioning (DIF). English language learners (ELLs) are a diverse group of students whose native language is not English. While they are still learning the English language, they must take their standardized…

  12. Linguistic Complexity, Schematic Representations, and Differential Item Functioning for English Language Learners in Math Tests

    ERIC Educational Resources Information Center

    Martiniello, Maria

    2009-01-01

    This article examines nonmathematical linguistic complexity as a source of differential item functioning (DIF) in math word problems for English language learners (ELLs). Specifically, this study investigates the relationship between item measures of linguistic complexity, nonlinguistic forms of representation and DIF measures based on item…

  13. Does Gender-Specific Differential Item Functioning Affect the Structure in Vocational Interest Inventories?

    ERIC Educational Resources Information Center

    Beinicke, Andrea; Pässler, Katja; Hell, Benedikt

    2014-01-01

    The study investigates consequences of eliminating items showing gender-specific differential item functioning (DIF) on the psychometric structure of a standard RIASEC interest inventory. Holland's hexagonal model was tested for structural invariance using a confirmatory methodological approach (confirmatory factor analysis and randomization…

  14. Assessing Motor Skills as a Differentiating Feature between High Functioning Autism and Asperger's Disorder

    ERIC Educational Resources Information Center

    Cid, Maria R.

    2011-01-01

    The purpose of this research was to investigate if motor skills could be used as a differentiating feature between Asperger's Disorder (AD) and High Functioning (HFA) in children under the age of 9 years, 0 months, in order to provide additional information regarding the usefulness and validity of distinguishing these two disorders. There is…

  15. Examining Differential Item Functions of Different Item Ordered Test Forms According to Item Difficulty Levels

    ERIC Educational Resources Information Center

    Çokluk, Ömay; Gül, Emrah; Dogan-Gül, Çilem

    2016-01-01

    The study aims to examine whether differential item function is displayed in three different test forms that have item orders of random and sequential versions (easy-to-hard and hard-to-easy), based on Classical Test Theory (CTT) and Item Response Theory (IRT) methods and bearing item difficulty levels in mind. In the correlational research, the…

  16. A Monte Carlo Study Investigating Missing Data, Differential Item Functioning, and Effect Size

    ERIC Educational Resources Information Center

    Garrett, Phyllis

    2009-01-01

    The use of polytomous items in assessments has increased over the years, and as a result, the validity of these assessments has been a concern. Differential item functioning (DIF) and missing data are two factors that may adversely affect assessment validity. Both factors have been studied separately, but DIF and missing data are likely to occur…

  17. The MIMIC Method with Scale Purification for Detecting Differential Item Functioning

    ERIC Educational Resources Information Center

    Wang, Wen-Chung; Shih, Ching-Lin; Yang, Chih-Chien

    2009-01-01

    This study implements a scale purification procedure onto the standard MIMIC method for differential item functioning (DIF) detection and assesses its performance through a series of simulations. It is found that the MIMIC method with scale purification (denoted as M-SP) outperforms the standard MIMIC method (denoted as M-ST) in controlling…

  18. Iterative Purification and Effect Size Use with Logistic Regression for Differential Item Functioning Detection

    ERIC Educational Resources Information Center

    French, Brian F.; Maller, Susan J.

    2007-01-01

    Two unresolved implementation issues with logistic regression (LR) for differential item functioning (DIF) detection include ability purification and effect size use. Purification is suggested to control inaccuracies in DIF detection as a result of DIF items in the ability estimate. Additionally, effect size use may be beneficial in controlling…

  19. The Matching Criterion Purification for Differential Item Functioning Analyses in a Large-Scale Assessment

    ERIC Educational Resources Information Center

    Lee, HyeSun; Geisinger, Kurt F.

    2016-01-01

    The current study investigated the impact of matching criterion purification on the accuracy of differential item functioning (DIF) detection in large-scale assessments. The three matching approaches for DIF analyses (block-level matching, pooled booklet matching, and equated pooled booklet matching) were employed with the Mantel-Haenszel…

  20. A Simulation Study of Methods for Assessing Differential Item Functioning in Computerized Adaptive Tests.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; And Others

    1994-01-01

    Simulated data were used to investigate the performance of modified versions of the Mantel-Haenszel method of differential item functioning (DIF) analysis in computerized adaptive tests (CAT). Results indicate that CAT-based DIF procedures perform well and support the use of item response theory-based matching variables in DIF analysis. (SLD)

  1. Descriptive and Inferential Procedures for Assessing Differential Item Functioning in Polytomous Items.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; Thayer, Dorothy T.; Mazzeo, John

    1997-01-01

    Differential item functioning (DIF) assessment procedures for items with more than two ordered score categories, referred to as polytomous items, were evaluated. Three descriptive statistics (standardized mean difference and two procedures based on the SIBTEST computer program) and five inferential procedures were used. Conditions under which the…

  2. A Simulation Study of Methods for Assessing Differential Item Functioning in Computer-Adaptive Tests.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; And Others

    Simulated data were used to investigate the performance of modified versions of the Mantel-Haenszel and standardization methods of differential item functioning (DIF) analysis in computer-adaptive tests (CATs). Each "examinee" received 25 items out of a 75-item pool. A three-parameter logistic item response model was assumed, and…

  3. Effects of Differential Item Functioning on Examinees' Test Performance and Reliability of Test

    ERIC Educational Resources Information Center

    Lee, Yi-Hsuan; Zhang, Jinming

    2017-01-01

    Simulations were conducted to examine the effect of differential item functioning (DIF) on measurement consequences such as total scores, item response theory (IRT) ability estimates, and test reliability in terms of the ratio of true-score variance to observed-score variance and the standard error of estimation for the IRT ability parameter. The…

  4. Parent Ratings of ADHD Symptoms: Generalized Partial Credit Model Analysis of Differential Item Functioning across Gender

    ERIC Educational Resources Information Center

    Gomez, Rapson

    2012-01-01

    Objective: Generalized partial credit model, which is based on item response theory (IRT), was used to test differential item functioning (DIF) for the "Diagnostic and Statistical Manual of Mental Disorders" (4th ed.), inattention (IA), and hyperactivity/impulsivity (HI) symptoms across boys and girls. Method: To accomplish this, parents completed…

  5. Differential Item Functioning By Sex and Race in The Hogan Personality Inventory

    ERIC Educational Resources Information Center

    Sheppard, Richard; Han, Kyunghee; Colarelli, Stephen M.; Dai, Guangdong; King, Daniel W.

    2006-01-01

    The authors examined measurement bias in the Hogan Personality Inventory by investigating differential item functioning (DIF) across sex and two racial groups (Caucasian and Black). The sample consisted of 1,579 Caucasians (1,023 men, 556 women) and 523 Blacks (321 men, 202 women) who were applying for entry-level, unskilled jobs in factories.…

  6. Fracture resistance of weakened teeth restored using accessory glass fiber posts.

    PubMed

    da Rosa, Ricardo Abreu; Barreto, Mirela Sangoi; da Rosa, Tiago Abreu; Reis, Katia Rodrigues; Kaizer, Osvaldo Bazzan

    2013-01-01

    This study used differential root weakening to evaluate the fracture resistance of bovine teeth restored using glass fiber posts (with or without accessory glass fiber posts). Fifty bovine mandibular incisors were sectioned 14 mm from the apex, fixed in acrylic resin blocks, and divided into 5 groups: healthy roots with a glass fiber post (Group 1), partially weakened teeth with a glass fiber post (Group 2), partially weakened teeth with a glass fiber post and 2 accessory glass fiber posts (Group 3), extensively weakened teeth with a glass fiber post (Group 4), and extensively weakened teeth with a glass fiber post and 5 accessory glass fiber posts (Group 5). Posts were luted with resin cement, cores were prepared using composite resin, and metallic crowns were cemented. The specimens were stored in distilled water at 37°C for more than 72 hours until the fracture resistance test. Specimens were loaded at 135 degrees relative to the long axis of the tooth at a crosshead speed of 0.5 mm/minute in a universal testing machine. All groups predominantly exhibited favorable failure patterns and there were no statistically significant differences between groups (two-way ANOVA, α = 0.05).

  7. Diabetic human adipose tissue-derived mesenchymal stem cells fail to differentiate in functional adipocytes.

    PubMed

    Barbagallo, Ignazio; Li Volti, Giovanni; Galvano, Fabio; Tettamanti, Guido; Pluchinotta, Francesca R; Bergante, Sonia; Vanella, Luca

    2016-11-30

    Adipose tissue dysfunction represents a hallmark of diabetic patients and is a consequence of the altered homeostasis of this tissue. Mesenchymal stem cells (MSCs) and their differentiation into adipocytes contribute significantly in maintaining the mass and function of adult adipose tissue. The aim of this study was to evaluate the differentiation of MSCs from patients suffering type 2 diabetes (dASC) and how such process results in hyperplasia or rather a stop of adipocyte turnover resulting in hypertrophy of mature adipocytes. Our results showed that gene profile of all adipogenic markers is not expressed in diabetic cells after differentiation indicating that diabetic cells fail to differentiate into adipocytes. Interestingly, delta like 1, peroxisome proliferator-activated receptor alpha, and interleukin 1β were upregulated whereas Sirtuin 1 and insulin receptor substrate 1 gene expression were found downregulated in dASC compared to cells obtained from healthy subjects. Taken together our data indicate that dASC lose their ability to differentiate into mature and functional adipocytes. In conclusion, our in vitro study is the first to suggest that diabetic patients might develop obesity through a hypertrophy of existing mature adipocytes due to failure turnover of adipose tissue.

  8. Berberine bioisostere Q8 compound stimulates osteoblast differentiation and function in vitro.

    PubMed

    Han, Younho; Jin, Yifeng; Lee, Sung Ho; Khadka, Daulat Bikram; Cho, Won-Jea; Lee, Kwang Youl

    2017-03-07

    The Q8 compound is a unique derivative of berberine. The present study investigated the functional role of Q8 to evaluate its potential for use in bone regeneration, especially in osteoblast differentiation. The safe concentration of Q8 increased BMP4-induced alkaline phosphatase (ALP) activity, and induced RNA expression of ALP, bone sialoprotein (BSP), and osteocalcin (OC). The activities of ALP-, BSP- and OC-luciferase reporters were also increased by Q8. During osteoblast differentiation, Q8 stabilized the Runx2 and Osterix protein abundance by blocking the ubiquitin-proteasome pathway, which in turn promoted Runx2 and Osterix induced transcriptional activity and subsequently increased the osteoblast differentiation. Meanwhile, depletion of Runx2 and Osterix markedly abolished the bone anabolic effect of Q8 on osteoblast differentiation. To evaluate the signal transduction pathway involved in the Q8-mediated regulation of Runx2 and Osterix, we examined the reporter assay using various kinase inhibitors. Treatment with a protein kinase A (PKA) inhibitor, H89 inhibited the Q8-mediated regulation of Runx2 and Osterix. Based on these findings, this study demonstrates that Q8 promotes the osteoblast differentiation by stabilization of Runx2/Osterix through the increased activation of PKA signaling. The enhancement of osteoblast function by Q8 may contribute to the prevention for osteoporosis.

  9. Successful treatment of accessory breast cancer with endocrine therapy#

    PubMed Central

    Wang, Chun-Xi; Guo, Shu-Li; Han, Li-Na

    2017-01-01

    Accessory breast cancers in males are extremely rare, and only a few cases have been reported in the literature. In this paper, an 87-year-old male patient was diagnosed with an accessory breast cancer by means of computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography-computed tomography (PET-CT), and immunohistochemistry based on needle biopsy, and has undergone successful resection and postoperative adjuvant endocrine therapy. He was the oldest male patient with an accessory breast cancer reported in the Chinese Hospital Knowledge Database and PubMed literature from 1975 to 2015. PMID:28070998

  10. Potential role of Arabidopsis PHP as an accessory subunit of the PAF1 transcriptional cofactor.

    PubMed

    Park, Sunchung; Ek-Ramos, Maria Julissa; Oh, Sookyung; van Nocker, Steven

    2011-08-01

    Paf1C is a transcriptional cofactor that has been implicated in various transcription-associated mechanisms spanning initiation, elongation and RNA processing, and is important for multiple aspects of development in Arabidopsis. Our recent studies suggest Arabidopsis Paf1C is crucial for proper regulation of genes within H3K27me3-enriched chromatin, and that a protein named PHP may act as an accessory subunit of Paf1C that promotes this function.

  11. Tracking the Spatial and Functional Gradient of Monocyte-To-Macrophage Differentiation in Inflamed Lung

    PubMed Central

    Sen, Debasish; Jones, Stephen M.; Oswald, Erin M.; Pinkard, Henry; Corbin, Kaitlin

    2016-01-01

    Myeloid-derived cells such as monocytes, dendritic cells (DCs), and macrophages are at the heart of the immune effector function in an inflammatory response. But because of the lack of an efficient imaging system to trace these cells live during their migration and maturation in their native environment at sub-cellular resolution, our knowledge is limited to data available from specific time-points analyzed by flow cytometry, histology, genomics and other immunological methods. Here, we have developed a ratiometric imaging method for measuring monocyte maturation in inflamed mouse lungs in situ using real-time using 2-photon imaging and complementary methods. We visualized that while undifferentiated monocytes were predominantly found only in the vasculature, a semi-differentiated monocyte/macrophage population could enter the tissue and resembled more mature and differentiated populations by morphology and surface phenotype. As these cells entered and differentiated, they were already selectively localized near inflamed airways and their entry was associated with changes in motility and morphology. We were able to visualize these during the act of differentiation, a process that can be demonstrated in this way to be faster on a per-cell basis under inflammatory conditions. Finally, our in situ analyses demonstrated increases, in the differentiating cells, for both antigen uptake and the ability to mediate interactions with T cells. This work, while largely confirming proposed models for in situ differentiation, provides important in situ data on the coordinated site-specific recruitment and differentiation of these cells and helps elaborate the predominance of immune pathology at the airways. Our novel imaging technology to trace immunogenic cell maturation in situ will complement existing information available on in situ differentiation deduced from other immunological methods, and assist better understanding of the spatio-temporal cellular behavior during an

  12. Exponential rational function method for space-time fractional differential equations

    NASA Astrophysics Data System (ADS)

    Aksoy, Esin; Kaplan, Melike; Bekir, Ahmet

    2016-04-01

    In this paper, exponential rational function method is applied to obtain analytical solutions of the space-time fractional Fokas equation, the space-time fractional Zakharov Kuznetsov Benjamin Bona Mahony, and the space-time fractional coupled Burgers' equations. As a result, some exact solutions for them are successfully established. These solutions are constructed in fractional complex transform to convert fractional differential equations into ordinary differential equations. The fractional derivatives are described in Jumarie's modified Riemann-Liouville sense. The exact solutions obtained by the proposed method indicate that the approach is easy to implement and effective.

  13. Human endometrial stromal stem cells differentiate into megakaryocytes with the ability to produce functional platelets.

    PubMed

    Wang, Jinju; Chen, Shuzhen; Zhang, Cheng; Stegeman, Samantha; Pfaff-Amesse, Teresa; Zhang, Ying; Zhang, Wenfeng; Amesse, Lawrence; Chen, Yanfang

    2012-01-01

    Human endometrium is a high dynamic tissue that contains endometrial stromal stem cells (hESSCs). The hESSCs have been differentiated into a number of cell lineages. However, differentiation of hESSCs into megakaryocytes (MKs) has not yet been investigated. The aim of this study was to investigate the feasibility of MK generation from hESSCs and subsequent production of functional platelets (PLTs). In our study, hESSCs were cultured from endometrial stromal cells as confirmed by positive stromal cell specific markers (CD90 and CD29) and negative hematopoietic stem cell markers (CD45 and CD34) expression. Then, hESSCs were differentiated in a medium supplemented with thrombopoietin (TPO) for 18 days. The MK differentiation was analyzed by flow cytometry and confocal microscopy. The differentiation medium was collected for PLT production analysis by flow cytometry, transmission electron microscopy and functional measurements. Our results show: 1) MKs were successfully generated from hESSCs as identified by expression of specific markers (CD41a: 1 ± 0.09% and 39 ± 3.0%; CD42b: 1.2 ± 0.06% and 28 ± 2.0%, control vs. differentiation) accompanied with reduction of pluripotent transcription factors (Oct4 and Sox2) expression; 2) The level of PLTs in the differentiation medium was 16 ± 1 number/µl as determined by size (2-4 µm) and CD41a expression (CD41a: 1 ± 0.4% and 90±2.0%, control vs. differentiation); 3) Generated PLTs were functional as evidenced by the up-regulation of CD62p expression and fibrinogen binding following thrombin stimulation; 4) Released PLTs showed similar ultra-structure characteristics (alpha granules, vacuoles and dense tubular system) as PLTs from peripheral blood determined by electron microscopic analysis. Data demonstrate the feasibility of generating MKs from hESSCs, and that the generated MKs release functional PLTs. Therefore, hESSCs could be a potential new stem cell source for in vitro MK/PLT production.

  14. Barrier function, epidermal differentiation, and human beta-defensin 2 expression in tinea corporis.

    PubMed

    Jensen, Jens-Michael; Pfeiffer, Stephan; Akaki, Tatsuya; Schröder, Jens-Michael; Kleine, Michael; Neumann, Claudia; Proksch, Ehrhardt; Brasch, Jochen

    2007-07-01

    Tinea corporis is a superficial mycotic infection resulting in substantial epidermal changes. We determined skin barrier function, epidermal differentiation, and human-beta-defensin 2 (hBD-2) protein expression in 10 patients with tinea corporis caused by Trichophyton rubrum (T. rubrum). We found disturbed skin barrier function as shown by a significant increase in transepidermal water loss (TEWL) and specific ultrastructural changes including disturbed formation of extracellular lipid bilayers, lamellar body extrusion, and deposit of clotted material at the stratum granulosum/stratum corneum interface. Epidermal proliferation in tinea increased several fold and accordingly, proliferation and inflammation-associated keratins K6, K16, and K17 were expressed. Expression of basal keratins K5 and K14 increased, whereas differentiation-associated K10 was reduced. Reduction of the cornified envelope proteins involucrin, loricrin, and the S100 protein filaggrin was also seen. Reduced filaggrin expression correlated with reduced skin hydration; protein breakdown products of filaggrin have been shown to be important for water binding. Surprisingly, we found pronounced epidermal protein expression of hBD-2, which may be related to disturbed epidermal differentiation and inflammation. hBD-2 showed a weak, although significant, antifungal activity against T. rubrum in the turbidimetric assay and the immunohistological staining was somewhat less pronounced in areas directly underneath fungal hyphae in the stratum corneum. Together, we describe profound changes in skin barrier structure and function, epidermal proliferation, and differentiation including pronounced protein expression of hBD-2 in tinea corporis.

  15. Temperament and arousal systems: A new synthesis of differential psychology and functional neurochemistry.

    PubMed

    Trofimova, Irina; Robbins, Trevor W

    2016-05-01

    This paper critically reviews the unidimensional construct of General Arousal as utilised by models of temperament in differential psychology for example, to underlie 'Extraversion'. Evidence suggests that specialization within monoamine neurotransmitter systems contrasts with the attribution of a "general arousal" of the Ascending Reticular Activating System. Experimental findings show specialized roles of noradrenaline, dopamine, and serotonin systems in hypothetically mediating three complementary forms of arousal that are similar to three functional blocks described in classical models of behaviour within kinesiology, clinical neuropsychology, psychophysiology and temperament research. In spite of functional diversity of monoamine receptors, we suggest that their functionality can be classified using three universal aspects of actions related to expansion, to selection-integration and to maintenance of chosen behavioural alternatives. Monoamine systems also differentially regulate analytic vs. routine aspects of activities at cortical and striatal neural levels. A convergence between main temperament models in terms of traits related to described functional aspects of behavioural arousal also supports the idea of differentiation between these aspects analysed here in a functional perspective.

  16. Functional maintenance of differentiated embryoid bodies in microfluidic systems: a platform for personalized medicine.

    PubMed

    Guven, Sinan; Lindsey, Jennifer S; Poudel, Ishwari; Chinthala, Sireesha; Nickerson, Michael D; Gerami-Naini, Behzad; Gurkan, Umut A; Anchan, Raymond M; Demirci, Utkan

    2015-03-01

    Hormone replacement therapies have become important for treating diseases such as premature ovarian failure or menopausal complications. The clinical use of bioidentical hormones might significantly reduce some of the potential risks reportedly associated with the use of synthetic hormones. In the present study, we demonstrate the utility and advantage of a microfluidic chip culture system to enhance the development of personalized, on-demand, treatment modules using embryoid bodies (EBs). Functional EBs cultured on microfluidic chips represent a platform for personalized, patient-specific treatment cassettes that can be cryopreserved until required for treatment. We assessed the viability, differentiation, and functionality of EBs cultured and cryopreserved in this system. During extended microfluidic culture, estradiol, progesterone, testosterone, and anti-müllerian hormone levels were measured, and the expression of differentiated steroidogenic cells was confirmed by immunocytochemistry assay for the ovarian tissue markers anti-müllerian hormone receptor type II, follicle-stimulating hormone receptor, and inhibin β-A and the estrogen biosynthesis enzyme aromatase. Our studies showed that under microfluidic conditions, differentiated steroidogenic EBs continued to secrete estradiol and progesterone at physiologically relevant concentrations (30-120 pg/ml and 150-450 pg/ml, respectively) for up to 21 days. Collectively, we have demonstrated for the first time the feasibility of using a microfluidic chip system with continuous flow for the differentiation and extended culture of functional steroidogenic stem cell-derived EBs, the differentiation of EBs into cells expressing ovarian antigens in a microfluidic system, and the ability to cryopreserve this system with restoration of growth and functionality on thawing. These results present a platform for the development of a new therapeutic system for personalized medicine.

  17. A New Class of Highly Accurate Differentiation Schemes Based on the Prolate Spheroidal Wave Functions

    DTIC Science & Technology

    2011-04-07

    absolute and relative errors to approximate the derivatives of functions f : [−1, 1] → R with bandlimit roughly c with differentiation matrices constructed...of dimension N − 2 Ec = relative l2 error when D or DC is used to approximate the second derivatives of the functions sin(cx)− x sin(c) and cos(cx...dates back to the first half of the nineteenth century, is the finite difference method. It approximates the derivative of a function f : R → R at a

  18. Estimation of time- and state-dependent delays and other parameters in functional differential equations

    NASA Technical Reports Server (NTRS)

    Murphy, K. A.

    1988-01-01

    A parameter estimation algorithm is developed which can be used to estimate unknown time- or state-dependent delays and other parameters (e.g., initial condition) appearing within a nonlinear nonautonomous functional differential equation. The original infinite dimensional differential equation is approximated using linear splines, which are allowed to move with the variable delay. The variable delays are approximated using linear splines as well. The approximation scheme produces a system of ordinary differential equations with nice computational properties. The unknown parameters are estimated within the approximating systems by minimizing a least-squares fit-to-data criterion. Convergence theorems are proved for time-dependent delays and state-dependent delays within two classes, which say essentially that fitting the data by using approximations will, in the limit, provide a fit to the data using the original system. Numerical test examples are presented which illustrate the method for all types of delay.

  19. Estimation of time- and state-dependent delays and other parameters in functional differential equations

    NASA Technical Reports Server (NTRS)

    Murphy, K. A.

    1990-01-01

    A parameter estimation algorithm is developed which can be used to estimate unknown time- or state-dependent delays and other parameters (e.g., initial condition) appearing within a nonlinear nonautonomous functional differential equation. The original infinite dimensional differential equation is approximated using linear splines, which are allowed to move with the variable delay. The variable delays are approximated using linear splines as well. The approximation scheme produces a system of ordinary differential equations with nice computational properties. The unknown parameters are estimated within the approximating systems by minimizing a least-squares fit-to-data criterion. Convergence theorems are proved for time-dependent delays and state-dependent delays within two classes, which say essentially that fitting the data by using approximations will, in the limit, provide a fit to the data using the original system. Numerical test examples are presented which illustrate the method for all types of delay.

  20. [Treatment of junctional paroxysmal tachycardia, without patent Wolff-Parkinson-White syndrome, by sectioning an accessory Kent-His bundle].

    PubMed

    Slama, R; Attuel, P; Flammang, D; Coumel, P; Guiraudon, G

    1976-11-01

    The authors report the case of a patient suffering from a Bouveret's tachycardia without syndrome of Wolff-Parkinson-White. The analysis of the tachycardic spells however showed that during a reciprocal crisis, the circuit went through a left accessory ventriculo-atrial bundle, functioning only in the reverse direction. This accessory bundle was successfully cut by the surgeon, following the procedure of wide atrioventricular desinsertion as described by the authors of Duke University for the surgical treatment of the Wolff-Parkinson-White syndrome.

  1. Compressive neuropathy of long thoracic nerve and accessory nerve secondary to heavy load bearing. A case report.

    PubMed

    Sahin, F; Yilmaz, F; Esit, N; Aysal, F; Kuran, B

    2007-03-01

    Carrying heavy loads that compress the shoulders is a possible etiological factor for both accessory and long thoracic nerve entrapment. In our patient, shouldering heavy loads damaged both nerves. A 27-year-old right-hand-dominant man was referred because of difficulty in raising his arms after a brief period of painful episodes due to heavy load bearing on both shoulders. Atrophic muscles around the shoulders, depressed and winged scapula were noted. An EMG confirmed entrapment of long thoracic and accessory nerves. An exercise program was instituted; 16 months after initial referral, though winged scapula was still noted, manual muscular strength had returned without functional limitation.

  2. 21 CFR 876.5090 - Suprapubic urological catheter and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... accessories is a flexible tubular device that is inserted through the abdominal wall into the urinary bladder with the aid of a trocar and cannula. The device is used to pass fluids to and from the urinary...

  3. 21 CFR 876.5090 - Suprapubic urological catheter and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... accessories is a flexible tubular device that is inserted through the abdominal wall into the urinary bladder with the aid of a trocar and cannula. The device is used to pass fluids to and from the urinary...

  4. 21 CFR 884.2740 - Perinatal monitoring system and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... heart rate by means of combining and coordinating uterine contraction and fetal heart monitors with... SERVICES (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Obstetrical and Gynecological Monitoring Devices § 884.2740 Perinatal monitoring system and accessories. (a) Identification. A...

  5. 21 CFR 884.2740 - Perinatal monitoring system and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... heart rate by means of combining and coordinating uterine contraction and fetal heart monitors with... SERVICES (CONTINUED) MEDICAL DEVICES OBSTETRICAL AND GYNECOLOGICAL DEVICES Obstetrical and Gynecological Monitoring Devices § 884.2740 Perinatal monitoring system and accessories. (a) Identification. A...

  6. 21 CFR 872.3980 - Endosseous dental implant accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... abutments, aid in the fabrication of dental prosthetics, and be used as an accessory with endosseous dental..., countertorque devices, placement and removal tools, laboratory pieces used for fabrication of dental...

  7. 21 CFR 872.3980 - Endosseous dental implant accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... abutments, aid in the fabrication of dental prosthetics, and be used as an accessory with endosseous dental..., countertorque devices, placement and removal tools, laboratory pieces used for fabrication of dental...

  8. 21 CFR 872.3980 - Endosseous dental implant accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... abutments, aid in the fabrication of dental prosthetics, and be used as an accessory with endosseous dental..., countertorque devices, placement and removal tools, laboratory pieces used for fabrication of dental...

  9. 21 CFR 872.3980 - Endosseous dental implant accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... abutments, aid in the fabrication of dental prosthetics, and be used as an accessory with endosseous dental..., countertorque devices, placement and removal tools, laboratory pieces used for fabrication of dental...

  10. 21 CFR 876.5630 - Peritoneal dialysis system and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... accessories is a device that is used as an artificial kidney system for the treatment of patients with renal failure or toxemic conditions, and that consists of a peritoneal access device, an administration set...

  11. 21 CFR 872.6010 - Abrasive device and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6010 Abrasive device and accessories... excessive restorative materials, such as gold, and to smooth rough surfaces from oral restorations, such...

  12. Complete Spinal Accessory Nerve Palsy From Carrying Climbing Gear.

    PubMed

    Coulter, Jess M; Warme, Winston J

    2015-09-01

    We report an unusual case of spinal accessory nerve palsy sustained while transporting climbing gear. Spinal accessory nerve injury is commonly a result of iatrogenic surgical trauma during lymph node excision. This particular nerve is less frequently injured by blunt trauma. The case reported here results from compression of the spinal accessory nerve for a sustained period-that is, carrying a load over the shoulder using a single nylon rope for 2.5 hours. This highlights the importance of using proper load-carrying equipment to distribute weight over a greater surface area to avoid nerve compression in the posterior triangle of the neck. The signs and symptoms of spinal accessory nerve palsy and its etiology are discussed. This report is particularly relevant to individuals involved in mountaineering and rock climbing but can be extended to anyone carrying a load with a strap over one shoulder and across the body.

  13. 21 CFR 872.4200 - Dental handpiece and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Identification. A dental handpiece and accessories is an AC-powered, water-powered, air-powered, or belt-driven... restorations, such as fillings, and for cleaning teeth. (b) Classification. Class I....

  14. 21 CFR 872.4200 - Dental handpiece and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Identification. A dental handpiece and accessories is an AC-powered, water-powered, air-powered, or belt-driven... restorations, such as fillings, and for cleaning teeth. (b) Classification. Class I....

  15. 21 CFR 872.6010 - Abrasive device and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6010 Abrasive device and accessories... excessive restorative materials, such as gold, and to smooth rough surfaces from oral restorations, such...

  16. PERSISTENT PUPILLARY MEMBRANE OR ACCESSORY IRIS MEMBRANE?.

    PubMed

    Gavriş, Monica; Horge, Ioan; Avram, Elena; Belicioiu, Roxana; Olteanu, Ioana Alexandra; Kedves, Hanga

    2015-01-01

    Frequently, in literature and curent practice, accessory iris membrane (AIM) and persistant pupillary membrane (PPM) are confused. Both AIM and PPM are congenital iris anomalies in which fine or thick iris strands arrise form the collarette and obscure the pupil. AIM, which is also called iris duplication, closely resembles the normal iris tissue in color and thickness and presents a virtual second pseudopupil aperture in the centre while PPM even in its extreme forms presents as a translucent or opaque membranous structure that extends across the pupil and has no pseudopupil. Mydriatiscs, laser treatment or surgery is used to clear the visual axis and optimize visual development. Surgical intervention is reserved for large, dense AIMs and PPMs. Our patient, a 29 year old male, has come with bilateral dense AIM, bilateral compound hyperopic astigmatism, BCVA OD = 0.6, BCVA OS = 0.4, IOP OU = 17 mmHg. To improve the visual acuity of the patient we decided to do a bilateral membranectomy, restoring in this way transparency of the visual axis. After surgery, the visual acuity improved to BCVA OD= 0.8, BCVA OS=0.8.

  17. A More General Model for Testing Measurement Invariance and Differential Item Functioning.

    PubMed

    Bauer, Daniel J

    2016-06-06

    The evaluation of measurement invariance is an important step in establishing the validity and comparability of measurements across individuals. Most commonly, measurement invariance has been examined using 1 of 2 primary latent variable modeling approaches: the multiple groups model or the multiple-indicator multiple-cause (MIMIC) model. Both approaches offer opportunities to detect differential item functioning within multi-item scales, and thereby to test measurement invariance, but both approaches also have significant limitations. The multiple groups model allows 1 to examine the invariance of all model parameters but only across levels of a single categorical individual difference variable (e.g., ethnicity). In contrast, the MIMIC model permits both categorical and continuous individual difference variables (e.g., sex and age) but permits only a subset of the model parameters to vary as a function of these characteristics. The current article argues that moderated nonlinear factor analysis (MNLFA) constitutes an alternative, more flexible model for evaluating measurement invariance and differential item functioning. We show that the MNLFA subsumes and combines the strengths of the multiple group and MIMIC models, allowing for a full and simultaneous assessment of measurement invariance and differential item functioning across multiple categorical and/or continuous individual difference variables. The relationships between the MNLFA model and the multiple groups and MIMIC models are shown mathematically and via an empirical demonstration. (PsycINFO Database Record

  18. Breakage-fusion-bridge cycles and large insertions contribute to the rapid evolution of accessory chromosomes in a fungal pathogen.

    PubMed

    Croll, Daniel; Zala, Marcello; McDonald, Bruce A

    2013-06-01

    Chromosomal rearrangements are a major driver of eukaryotic genome evolution, affecting speciation, pathogenicity and cancer progression. Changes in chromosome structure are often initiated by mis-repair of double-strand breaks in the DNA. Mis-repair is particularly likely when telomeres are lost or when dispersed repeats misalign during crossing-over. Fungi carry highly polymorphic chromosomal complements showing substantial variation in chromosome length and number. The mechanisms driving chromosome polymorphism in fungi are poorly understood. We aimed to identify mechanisms of chromosomal rearrangements in the fungal wheat pathogen Zymoseptoria tritici. We combined population genomic resequencing and chromosomal segment PCR assays with electrophoretic karyotyping and resequencing of parents and offspring from experimental crosses to show that this pathogen harbors a highly diverse complement of accessory chromosomes that exhibits strong global geographic differentiation in numbers and lengths of chromosomes. Homologous chromosomes carried highly differentiated gene contents due to numerous insertions and deletions. The largest accessory chromosome recently doubled in length through insertions totaling 380 kb. Based on comparative genomics, we identified the precise breakpoint locations of these insertions. Nondisjunction during meiosis led to chromosome losses in progeny of three different crosses. We showed that a new accessory chromosome emerged in two viable offspring through a fusion between sister chromatids. Such chromosome fusion is likely to initiate a breakage-fusion-bridge (BFB) cycle that can rapidly degenerate chromosomal structure. We suggest that the accessory chromosomes of Z. tritici originated mainly from ancient core chromosomes through a degeneration process that included BFB cycles, nondisjunction and mutational decay of duplicated sequences. The rapidly evolving accessory chromosome complement may serve as a cradle for adaptive evolution in

  19. Structure, expression, and biological function of INSM1 transcription factor in neuroendocrine differentiation

    PubMed Central

    Lan, Michael S.; Breslin, Mary B.

    2009-01-01

    Zinc-finger transcription factors are DNA-binding proteins that are implicated in many diverse biological functions. INSM1 (formerly IA-1) contains five zinc-finger motifs and functions as a transcription factor. INSM1 protein structure is highly conserved in homologues of different species. It is predominantly expressed in developing neuroendocrine tissues and the nervous system in mammals. INSM1 represents an important player in early embryonic neurogenesis. In pancreatic endocrine cell differentiation, Ngn3 first activates INSM1 and subsequently NeuroD/β2. Conversely, INSM1 exerts a feedback mechanism to suppress NeuroD/β2 and its own gene expression. INSM1 gene ablation in the mouse results in the impairment of pancreatic endocrine cell maturation. Further, deletion of INSM1 severely impairs catecholamine biosynthesis and secretion from the adrenal gland that results in early embryonic lethality. Genetically, INSM1 acts as a downstream factor of Mash 1 and Phox2b in the differentiation of the sympatho-adrenal lineage. In the developing neocortex, mouse embryos lacking INSM1 expression contain half the number of basal progenitors and show a reduction in cortical plate radial thickness. Cell signaling studies reveal that INSM1 contributes to the induction of cell cycle arrest/exit necessary to facilitate cellular differentiation. INSM1 is highly expressed in tumors of neuroendocrine origin. Hence, its promoter could serve as a tumor-specific promoter that drives a specific targeted cancer gene therapy for the treatment of neuroendocrine tumors. Taken together, all of these features of INSM1 strongly support its role as an important regulator during neuroendocrine differentiation.—Lan, M. S., Breslin, M. B. Structure, expression, and biological function of INSM1 transcription factor in neuroendocrine differentiation. PMID:19246490

  20. A New Integrated Onboard Charger and Accessory Power Converter for Plug-in Electric Vehicles

    SciTech Connect

    Su, Gui-Jia; Tang, Lixin

    2014-01-01

    In this paper, a new approach is presented for integrating the function of onboard battery charging into the traction drive system and accessory dc-dc converter of a plug-in electric vehicle (PEV). The idea is to utilize the segmented traction drive system of a PEV as the frond converter of the charging circuit and the transformer and high voltage converter of the 14 V accessory dc-dc converter to form a galvanically isolated onboard charger. Moreover, a control method is presented for suppressing the battery current ripple component of twice the grid frequency with the reduced dc bus capacitor in the segmented inverter. The resultant integrated charger has lower cost, weight, and volume than a standalone charger due to a substantially reduced component count. The proposed integrated charger topology was verified by modeling and experimental results on a 5.8 kW charger prototype.

  1. Faecal bile acids are natural ligands of the mouse accessory olfactory system

    PubMed Central

    Doyle, Wayne I.; Dinser, Jordan A.; Cansler, Hillary L.; Zhang, Xingjian; Dinh, Daniel D.; Browder, Natasha S.; Riddington, Ian M.; Meeks, Julian P.

    2016-01-01

    The accessory olfactory system (AOS) guides behaviours that are important for survival and reproduction, but understanding of AOS function is limited by a lack of identified natural ligands. Here we report that mouse faeces are a robust source of AOS chemosignals and identify bile acids as a class of natural AOS ligands. Single-unit electrophysiological recordings from accessory olfactory bulb neurons in ex vivo preparations show that AOS neurons are strongly and selectively activated by peripheral stimulation with mouse faecal extracts. Faecal extracts contain several unconjugated bile acids that cause concentration-dependent neuronal activity in the AOS. Many AOS neurons respond selectively to bile acids that are variably excreted in male and female mouse faeces, and others respond to bile acids absent in mouse faeces. These results identify faeces as a natural source of AOS information, and suggest that bile acids may be mammalian pheromones and kairomones. PMID:27324439

  2. Expression of an accessory cell phenotype by hairy cells during lymphocyte colony formation in agar culture.

    PubMed

    Farcet, J P; Gourdin, M F; Testa, U; Andre, C; Jouault, H; Reyes, F

    1983-01-01

    Human T lymphocytes require the cooperation of accessory cells to generate lymphocyte colonies in agar culture under PHA stimulation. Various hairy cell enriched fractions, as well as normal monocytes, have been found to be able to initiate colony formation by normal lymphocytes. Leukemic monocytes from CMML patients were also effective, but not the leukemic lymphocytes from CLL patients. The phenotype expressed by HC in agar colonies was further studied using cell surface and enzymatic markers. We have concluded that HC in agar culture in the presence of both normal T lymphocytes and PHA lose the B phenotype that they express in vivo and function like an accessory cell in contrast to normal or leukemic B lymphocytes.

  3. In vitro Differentiation of Functional Human Skeletal Myotubes in a Defined System.

    PubMed

    Guo, Xiufang; Greene, Keshel; Akanda, Nesar; Smith, Alec; Stancescu, Maria; Lambert, Stephen; Vandenburgh, Herman; Hickman, James

    2014-01-01

    In vitro human skeletal muscle systems are valuable tools for the study of human muscular development, disease and treatment. However, published in vitro human muscle systems have so far only demonstrated limited differentiation capacities. Advanced differentiation features such as cross-striations and contractility have only been observed in co-cultures with motoneurons. Furthermore, it is commonly regarded that cultured human myotubes do not spontaneously contract, and any contraction has been considered to originate from innervation. This study developed a serum-free culture system in which human skeletal myotubes demonstrated advanced differentiation. Characterization by immunocytochemistry, electrophysiology and analysis of contractile function revealed these major features: A) well defined sarcomeric development, as demonstrated by the presence of cross-striations. B) finely developed excitation-contraction coupling apparatus characterized by the close apposition of dihydropyridine receptors on T-tubules and Ryanodine receptors on sarcoplasmic reticulum membranes. C) spontaneous and electrically controlled contractility. This report not only demonstrates an improved level of differentiation of cultured human skeletal myotubes, but also provides the first published evidence that such myotubes are capable of spontaneous contraction. Use of this functional in vitro human skeletal muscle system would advance studies concerning human skeletal muscle development and physiology, as well as muscle-related disease and therapy.

  4. New mammary epithelial and fibroblastic cell clones in coculture form structures competent to differentiate functionally

    PubMed Central

    1989-01-01

    We have established and characterized a spontaneously immortalized, nontumorigenic mouse mammary cell line, designated IM-2. IM-2 cells synthesize large amounts of the milk protein beta-casein upon addition of lactogenic hormones. The induction of beta-casein occurs rapidly and does not require any exogenous extracellular matrix components. The IM- 2 cell line is morphologically heterogeneous and could be separated into cell clones with epithelial and fibroblastic characteristics. In monoculture, none of the epithelial clones could be induced to synthesize caseins. Coculture of epithelial and fibroblastic clones, however, rendered the epithelial cells competent to differentiate functionally; the addition of lactogenic hormones to these cocultures resulted in the synthesis of beta-casein in amounts comparable to that seen with the original IM-2 line. Using this unique cell system, we have investigated the interrelationships between different steps in differentiation leading to hormone-induced casein production. Independent of hormones, epithelial-fibroblastic cell contacts led to the formation of characteristic structures showing the deposition of laminin. We found that the epithelial cells located in these structures also exhibited significantly increased levels of cytokeratin intermediate filament polypeptides. Double immunofluorescence revealed that the cells inducible by hormones to synthesize casein, colocalized exactly with the areas of laminin deposition and with the cells showing greatly intensified cytokeratin expression. These results suggest that hormone-independent differentiation events take place in response to intercellular epithelial-mesenchymal contacts. These events in turn bring about a state of competence for functional differentiation after lactogenic hormonal stimulation. PMID:2466037

  5. Multipotent adult progenitor cells from bone marrow differentiate into functional hepatocyte-like cells

    PubMed Central

    Schwartz, Robert E.; Reyes, Morayma; Koodie, Lisa; Jiang, Yuehua; Blackstad, Mark; Lund, Troy; Lenvik, Todd; Johnson, Sandra; Hu, Wei-Shou; Verfaillie, Catherine M.

    2002-01-01

    We have derived from normal human, mouse, and rat postnatal bone marrow primitive, multipotent adult progenitor cells (MAPCs) that can differentiate into most mesodermal cells and neuroectodermal cells in vitro and into all embryonic lineages in vivo. Here, we show that MAPCs can also differentiate into hepatocyte-like cells in vitro. Human, mouse, and rat MAPCs, cultured on Matrigel with FGF-4 and HGF, differentiated into epithelioid cells that expressed hepatocyte nuclear factor-3β (HNF-3β), GATA4, cytokeratin 19 (CK19), transthyretin, and α-fetoprotein by day 7, and expressed CK18, HNF-4, and HNF-1α on days 14–28. Virtually all human, as well as a majority of rodent cells stained positive for albumin and CK18 on day 21; 5% (rodent) to 25% (human) cells were binucleated by day 21. These cells also acquired functional characteristics of hepatocytes: they secreted urea and albumin, had phenobarbital-inducible cytochrome p450, could take up LDL, and stored glycogen. MAPCs, which can be expanded in vitro and maintained in an undifferentiated state for more than 100 population doublings, can thus differentiate into cells with morphological, phenotypic, and functional characteristics of hepatocytes. MAPCs may therefore be an ideal cell for in vivo therapies for liver disorders or for use in bioartificial liver devices. PMID:12021244

  6. An Efficient Spectral Method for Ordinary Differential Equations with Rational Function Coefficients

    NASA Technical Reports Server (NTRS)

    Coutsias, Evangelos A.; Torres, David; Hagstrom, Thomas

    1994-01-01

    We present some relations that allow the efficient approximate inversion of linear differential operators with rational function coefficients. We employ expansions in terms of a large class of orthogonal polynomial families, including all the classical orthogonal polynomials. These families obey a simple three-term recurrence relation for differentiation, which implies that on an appropriately restricted domain the differentiation operator has a unique banded inverse. The inverse is an integration operator for the family, and it is simply the tridiagonal coefficient matrix for the recurrence. Since in these families convolution operators (i.e. matrix representations of multiplication by a function) are banded for polynomials, we are able to obtain a banded representation for linear differential operators with rational coefficients. This leads to a method of solution of initial or boundary value problems that, besides having an operation count that scales linearly with the order of truncation N, is computationally well conditioned. Among the applications considered is the use of rational maps for the resolution of sharp interior layers.

  7. In vitro Differentiation of Functional Human Skeletal Myotubes in a Defined System

    PubMed Central

    Guo, Xiufang; Greene, Keshel; Akanda, Nesar; Smith, Alec; Stancescu, Maria; Lambert, Stephen; Vandenburgh, Herman; Hickman, James

    2013-01-01

    In vitro human skeletal muscle systems are valuable tools for the study of human muscular development, disease and treatment. However, published in vitro human muscle systems have so far only demonstrated limited differentiation capacities. Advanced differentiation features such as cross-striations and contractility have only been observed in co-cultures with motoneurons. Furthermore, it is commonly regarded that cultured human myotubes do not spontaneously contract, and any contraction has been considered to originate from innervation. This study developed a serum-free culture system in which human skeletal myotubes demonstrated advanced differentiation. Characterization by immunocytochemistry, electrophysiology and analysis of contractile function revealed these major features: A) well defined sarcomeric development, as demonstrated by the presence of cross-striations. B) finely developed excitation-contraction coupling apparatus characterized by the close apposition of dihydropyridine receptors on T-tubules and Ryanodine receptors on sarcoplasmic reticulum membranes. C) spontaneous and electrically controlled contractility. This report not only demonstrates an improved level of differentiation of cultured human skeletal myotubes, but also provides the first published evidence that such myotubes are capable of spontaneous contraction. Use of this functional in vitro human skeletal muscle system would advance studies concerning human skeletal muscle development and physiology, as well as muscle-related disease and therapy. PMID:24516722

  8. It Might Not Make a Big DIF: Improved Differential Test Functioning Statistics That Account for Sampling Variability

    ERIC Educational Resources Information Center

    Chalmers, R. Philip; Counsell, Alyssa; Flora, David B.

    2016-01-01

    Differential test functioning, or DTF, occurs when one or more items in a test demonstrate differential item functioning (DIF) and the aggregate of these effects are witnessed at the test level. In many applications, DTF can be more important than DIF when the overall effects of DIF at the test level can be quantified. However, optimal statistical…

  9. An NCME Instructional Module on Using Differential Step Functioning to Refine the Analysis of DIF in Polytomous Items

    ERIC Educational Resources Information Center

    Penfield, Randall D.; Gattamorta, Karina; Childs, Ruth A.

    2009-01-01

    Traditional methods for examining differential item functioning (DIF) in polytomously scored test items yield a single item-level index of DIF and thus provide no information concerning which score levels are implicated in the DIF effect. To address this limitation of DIF methodology, the framework of differential step functioning (DSF) has…

  10. Using a Taxonomy of Differential Step Functioning to Improve the Interpretation of DIF in Polytomous Items: An Illustration

    ERIC Educational Resources Information Center

    Penfield, Randall D.; Alvarez, Karina; Lee, Okhee

    2009-01-01

    The assessment of differential item functioning (DIF) in polytomous items addresses between-group differences in measurement properties at the item level, but typically does not inform which score levels may be involved in the DIF effect. The framework of differential step functioning (DSF) addresses this issue by examining between-group…

  11. A New Method for Assessing the Statistical Significance in the Differential Functioning of Items and Tests (DFIT) Framework

    ERIC Educational Resources Information Center

    Oshima, T. C.; Raju, Nambury S.; Nanda, Alice O.

    2006-01-01

    A new item parameter replication method is proposed for assessing the statistical significance of the noncompensatory differential item functioning (NCDIF) index associated with the differential functioning of items and tests framework. In this new method, a cutoff score for each item is determined by obtaining a (1-alpha ) percentile rank score…

  12. Investigating Linguistic Sources of Differential Item Functioning Using Expert Think-Aloud Protocols in Science Achievement Tests

    ERIC Educational Resources Information Center

    Roth, Wolff-Michael; Oliveri, Maria Elena; Sandilands, Debra Dallie; Lyons-Thomas, Juliette; Ercikan, Kadriye

    2013-01-01

    Even if national and international assessments are designed to be comparable, subsequent psychometric analyses often reveal differential item functioning (DIF). Central to achieving comparability is to examine the presence of DIF, and if DIF is found, to investigate its sources to ensure differentially functioning items that do not lead to bias.…

  13. Regeneration of Thyroid Function by Transplantation of Differentiated Pluripotent Stem Cells.

    PubMed

    Kurmann, Anita A; Serra, Maria; Hawkins, Finn; Rankin, Scott A; Mori, Munemasa; Astapova, Inna; Ullas, Soumya; Lin, Sui; Bilodeau, Melanie; Rossant, Janet; Jean, Jyh C; Ikonomou, Laertis; Deterding, Robin R; Shannon, John M; Zorn, Aaron M; Hollenberg, Anthony N; Kotton, Darrell N

    2015-11-05

    Differentiation of functional thyroid epithelia from pluripotent stem cells (PSCs) holds the potential for application in regenerative medicine. However, progress toward this goal is hampered by incomplete understanding of the signaling pathways needed for directed differentiation without forced overexpression of exogenous transgenes. Here we use mouse PSCs to identify key conserved roles for BMP and FGF signaling in regulating thyroid lineage specification from foregut endoderm in mouse and Xenopus. Thyroid progenitors derived from mouse PSCs can be matured into thyroid follicular organoids that provide functional secretion of thyroid hormones in vivo and rescue hypothyroid mice after transplantation. Moreover, by stimulating the same pathways, we were also able to derive human thyroid progenitors from normal and disease-specific iPSCs generated from patients with hypothyroidism resulting from NKX2-1 haploinsufficiency. Our studies have therefore uncovered the regulatory mechanisms that underlie early thyroid organogenesis and provide a significant step toward cell-based regenerative therapy for hypothyroidism.

  14. Recovery of partial differential operators on classes of periodic functions with mixed smoothness

    NASA Astrophysics Data System (ADS)

    Balgimbayeva, Sholpan

    2016-08-01

    We consider the problem of optimal linear recovery for mixed partial differential operator A on the unit ball SBpθ r(Tn) of the Nikol'skii-Besov space of periodic functions with mixed smoothness. We find error bounds sharp in order for optimal linear recovery of operator A on class SBpθ r(Tn) . As information IMδ(f ) about the functions f from class SBpθ r(Tn) we shall use Fourier coefficients with numbers from step "hyperbolic" cross. As the linear method using the information about Fourier coefficients, we shall consider action of the mixed partial differential operator A on the special "private" sum of decomposition on system (type as wavelets) trigonometric polynomials.

  15. Unsteady Solution of Non-Linear Differential Equations Using Walsh Function Series

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.

    2015-01-01

    Walsh functions form an orthonormal basis set consisting of square waves. The discontinuous nature of square waves make the system well suited for representing functions with discontinuities. The product of any two Walsh functions is another Walsh function - a feature that can radically change an algorithm for solving non-linear partial differential equations (PDEs). The solution algorithm of non-linear differential equations using Walsh function series is unique in that integrals and derivatives may be computed using simple matrix multiplication of series representations of functions. Solutions to PDEs are derived as functions of wave component amplitude. Three sample problems are presented to illustrate the Walsh function series approach to solving unsteady PDEs. These include an advection equation, a Burgers equation, and a Riemann problem. The sample problems demonstrate the use of the Walsh function solution algorithms, exploiting Fast Walsh Transforms in multi-dimensions (O(Nlog(N))). Details of a Fast Walsh Reciprocal, defined here for the first time, enable inversion of aWalsh Symmetric Matrix in O(Nlog(N)) operations. Walsh functions have been derived using a fractal recursion algorithm and these fractal patterns are observed in the progression of pairs of wave number amplitudes in the solutions. These patterns are most easily observed in a remapping defined as a fractal fingerprint (FFP). A prolongation of existing solutions to the next highest order exploits these patterns. The algorithms presented here are considered a work in progress that provide new alternatives and new insights into the solution of non-linear PDEs.

  16. Cherubism Gene Sh3bp2 is Important for Optimal Bone Formation, Osteoblast Differentiation and Function

    PubMed Central

    Mukherjee, Padma M.; Wang, Chiachien J.; Chen, I-Ping; Jafarov, Toghrul; Olsen, Bjorn R.; Ueki, Yasuyoshi; Reichenberger, Ernst J.

    2012-01-01

    Introduction Cherubism is a human genetic disorder that causes bilateral symmetrical enlargement of the maxilla and mandible in children. It is caused by mutations in SH3BP2. The exact pathogenesis of the disorder is an area of active research. Sh3bp2 knock-in mice were developed by introducing a Pro416Arg mutation (Pro418Arg in humans) in the mouse genome. The osteoclast phenotype of this mouse model was recently described. Methods We examined the bone phenotype of the cherubism mouse model, the role of Sh3bp2 during bone formation, osteoblast differentiation and osteoblast function. Results We observed delays in early postnatal development of homozygous Sh3bp2KI/KI mice. Sh3bp2KI/KI mice exhibit increased growth plate thickness and significantly decreased trabecular bone thickness and reduced bone mineral density. Histomorphometric and μ-CT analyses reveal bone loss in cranial and appendicular skeleton. Sh3bp2KI/KI mice also exhibit a significant decrease in osteoid formation that indicates a defect in osteoblast function. Calvarial osteoblast cell cultures exhibit a decrease in alkaline phosphatase expression and mineralization suggesting reduced differentiation potential. Gene expression of osteoblast differentiation markers like collagen type-I, alkaline phosphatase and osteocalcin are decreased in osteoblast cultures from Sh3bp2KI/KI mice. Conclusions These data suggest that Sh3bp2 function regulates bone homeostasis not only through osteoclast-specific effects but also through effects on osteoblast differentiation and function. PMID:20691350

  17. Finite-difference models of ordinary differential equations - Influence of denominator functions

    NASA Technical Reports Server (NTRS)

    Mickens, Ronald E.; Smith, Arthur

    1990-01-01

    This paper discusses the influence on the solutions of finite-difference schemes of using a variety of denominator functions in the discrete modeling of the derivative for any ordinary differential equation. The results obtained are a consequence of using a generalized definition of the first derivative. A particular example of the linear decay equation is used to illustrate in detail the various solution possibilities that can occur.

  18. The DIF-Free-Then-DIF Strategy for the Assessment of Differential Item Functioning

    ERIC Educational Resources Information Center

    Wang, Wen-Chung; Shih, Ching-Lin; Sun, Guo-Wei

    2012-01-01

    The DIF-free-then-DIF (DFTD) strategy consists of two steps: (a) select a set of items that are the most likely to be DIF-free and (b) assess the other items for DIF (differential item functioning) using the designated items as anchors. The rank-based method together with the computer software IRTLRDIF can select a set of DIF-free polytomous items…

  19. Cool and hot executive function as predictors of aggression in early childhood: Differentiating between the function and form of aggression.

    PubMed

    Poland, Sarah E; Monks, Claire P; Tsermentseli, Stella

    2016-06-01

    Executive function (EF) has been implicated in childhood aggression. Understanding of the role of EF in aggression has been hindered, however, by the lack of research taking into account the function and form of aggression and the almost exclusive focus on cool EF. This study examined the role of cool and hot EF in teacher reported aggression, differentiating between reactive and proactive as well as physical and relational aggression. Children (N = 106) completed laboratory tasks measuring cool (inhibition, planning, working memory) and hot EF (affective decision-making, delay of gratification). Cool, but not hot, EF significantly contributed to understanding of childhood aggression. Inhibition was a central predictor of childhood aggression. Planning and working memory, in contrast, were significant independent predictors of proactive relational aggression only. Added to this, prosocial behaviour moderated the relationship between working memory and reactive relational aggression. This study therefore suggests that cool EF, particularly inhibition, is associated with childhood aggression across the different functions and forms.

  20. Accessory Soleus: A Case Report of Exertional Compartment and Tarsal Tunnel Syndrome Associated With an Accessory Soleus Muscle.

    PubMed

    Carrington, Scott C; Stone, Paul; Kruse, Dustin

    2016-01-01

    An accessory soleus muscle is a rare anatomic variant that frequently presents as an asymptomatic soft tissue swelling in the posteromedial ankle. Less frequently, the anomalous muscle can cause pain and swelling with activity. We present the case of a 17-year-old male with exertional compartment syndrome and associated tarsal tunnel syndrome secondary to a very large accessory soleus muscle. After surgical excision, the patient was able to return to full activity with complete resolution of symptoms.

  1. Small functional groups for controlled differentiation of hydrogel-encapsulated human mesenchymal stem cells

    NASA Astrophysics Data System (ADS)

    Benoit, Danielle S. W.; Schwartz, Michael P.; Durney, Andrew R.; Anseth, Kristi S.

    2008-10-01

    Cell-matrix interactions have critical roles in regeneration, development and disease. The work presented here demonstrates that encapsulated human mesenchymal stem cells (hMSCs) can be induced to differentiate down osteogenic and adipogenic pathways by controlling their three-dimensional environment using tethered small-molecule chemical functional groups. Hydrogels were formed using sufficiently low concentrations of tether molecules to maintain constant physical characteristics, encapsulation of hMSCs in three dimensions prevented changes in cell morphology, and hMSCs were shown to differentiate in normal growth media, indicating that the small-molecule functional groups induced differentiation. To our knowledge, this is the first example where synthetic matrices are shown to control induction of multiple hMSC lineages purely through interactions with small-molecule chemical functional groups tethered to the hydrogel material. Strategies using simple chemistry to control complex biological processes would be particularly powerful as they could make production of therapeutic materials simpler, cheaper and more easily controlled.

  2. Assessing impact of differential symptom functioning on post-traumatic stress disorder (PTSD) diagnosis.

    PubMed

    He, Qiwei; Glas, Cees A W; Veldkamp, Bernard P

    2014-06-01

    This article explores the generalizability of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) diagnostic criteria for post-traumatic stress disorder (PTSD) to various subpopulations. Besides identifying the differential symptom functioning (also referred to as differential item functioning [DIF]) related to various background variables such as gender, marital status and educational level, this study emphasizes the importance of evaluating the impact of DIF on population inferences as made in health surveys and clinical trials, and on the diagnosis of individual patients. Using a sample from the National Comorbidity Study-Replication (NCS-R), four symptoms for gender, one symptom for marital status, and three symptoms for educational level were significantly flagged as DIF, but their impact on diagnosis was fairly small. We conclude that the DSM-IV diagnostic criteria for PTSD do not produce substantially biased results in the investigated subpopulations, and there should be few reservations regarding their use. Further, although the impact of DIF (i.e. the influence of differential symptom functioning on diagnostic results) was found to be quite small in the current study, we recommend that diagnosticians always perform a DIF analysis of various subpopulations using the methodology presented here to ensure the diagnostic criteria is valid in their own studies.

  3. From Monocytes to M1/M2 Macrophages: Phenotypical vs. Functional Differentiation

    PubMed Central

    Italiani, Paola; Boraschi, Diana

    2014-01-01

    Studies on monocyte and macrophage biology and differentiation have revealed the pleiotropic activities of these cells. Macrophages are tissue sentinels that maintain tissue integrity by eliminating/repairing damaged cells and matrices. In this M2-like mode, they can also promote tumor growth. Conversely, M1-like macrophages are key effector cells for the elimination of pathogens, virally infected, and cancer cells. Macrophage differentiation from monocytes occurs in the tissue in concomitance with the acquisition of a functional phenotype that depends on microenvironmental signals, thereby accounting for the many and apparently opposed macrophage functions. Many questions arise. When monocytes differentiate into macrophages in a tissue (concomitantly adopting a specific functional program, M1 or M2), do they all die during the inflammatory reaction, or do some of them survive? Do those that survive become quiescent tissue macrophages, able to react as naïve cells to a new challenge? Or, do monocyte-derived tissue macrophages conserve a “memory” of their past inflammatory activation? This review will address some of these important questions under the general framework of the role of monocytes and macrophages in the initiation, development, resolution, and chronicization of inflammation. PMID:25368618

  4. Isolating D" structure using ScS-S differential response functions

    NASA Astrophysics Data System (ADS)

    Fisher, J.; Wysession, M.

    2003-04-01

    Differential seismic phase studies are commonly used for isolating anomalies in a particular region of the Earth. We present a method called differential response functions, DRFs, which not only isolate a travel time or attenuation measurement, but also isolate the differential response of a region. While this technique may be used with any number of phases, we demonstrate its usefulness using ScS and S phases to examine D" seismic structure. The differential response function is simply the transfer function between the ScS and S phases. By deconvolving the S phase from the ScS phase we remove source, receiver, and upper mantle contributions to the ScS phase. The remaining signal is a function of the lower mantle response to the S and ScS. The DRF contains information regarding quality factor, velocity contrasts at interfaces, interface depths, and velocities. Variations in the D" quality factor, Qμ(D"), and shear velocity, Vβ, produce significant changes to synthetic DRFs. Low velocity layers within D" produce DRFs with delayed phase corresponding to differential travel-time measurements. Attenuated ScS phases have measured attenuation values, t*, corresponding to the difference between S and ScS attenuation, δ t*(ScS-S). The shape of the DRF reflects ScS interaction with large interfaces, such as the entrance into and exit from a low velocity layer. The relative amplitude of the ScS to S phase is also maintained, allowing for improved estimates of velocity contrast at an interface. The major boon of DRF's is that they allow direct modeling of an isolated region within the earth such as D". Additional advantages of the DRF (over standard differential anomaly measurement techniques) include their ease of stacking, their dependence upon interfaces, and their simultaneous isolation of both elastic and anelastic measurements alike. Variations in the observed ScS-S DRF shape from region to region may indicate large differences between lower mantle structures

  5. Anatrophic nephrolithotomy: preservation of renal function demonstrated by differential quantitative radionuclide renal scans.

    PubMed

    Belis, J A; Morabito, R A; Kandzari, S J; Lai, J C; Gabriele, O F

    1981-06-01

    Differential quantitative radionuclide renal scans have been used to confirm that early removal of staghorn calculi by anatrophic nephrolithotomy preserves renal parenchyma without significant renal damage by the surgical procedure. The 99mtechnetium diethylenetriaminepentaacetic acid scan was useful in predicting recovery of function in the involved kidney, while the 131iodine orthoiodohippurate scan provided a quantitative evaluation of the effect of the surgical procedure on individual kidney function. All of 13 consecutive patients evaluated by 131iodine orthoiodohippurate renal scans had stable or improved effective renal plasma flow to the involved kidney and an unchanged or improved total excretory index 6 months after nephrolithotomy.

  6. Anatrophic nephrolithotomy: preservation of renal function demonstrated by differential quantitative radionuclide renal scans

    SciTech Connect

    Belis, J.A.; Morabito, R.A.; Kandzari, S.J.; Lai, J.C.; Gabriele, O.F.

    1981-06-01

    Differential quantitative radionuclide renal scans have been used to confirm that early removal of staghorn calculi by anatrophic nephrolithotomy preserves renal parenchyma without significant renal damage by the surgical procedure. The /sup 99m/technetium diethylenetriaminepentaacetic acid scan was useful in predicting recovery of function in the involved kidney, while the /sup 131/iodine orthoiodohippurate scan provided a quantitative evaluation of the effect of the surgical procedure on individual kidney function. All of 13 consecutive patients evaluated by /sup 131/iodine orthoiodohippurate renal scans had stable or improved effective renal plasma flow to the involved kidney and an unchanged or improved total excretory index 6 months after nephrolithotomy.

  7. New results for global exponential synchronization in neural networks via functional differential inclusions.

    PubMed

    Wang, Dongshu; Huang, Lihong; Tang, Longkun

    2015-08-01

    This paper is concerned with the synchronization dynamical behaviors for a class of delayed neural networks with discontinuous neuron activations. Continuous and discontinuous state feedback controller are designed such that the neural networks model can realize exponential complete synchronization in view of functional differential inclusions theory, Lyapunov functional method and inequality technique. The new proposed results here are very easy to verify and also applicable to neural networks with continuous activations. Finally, some numerical examples show the applicability and effectiveness of our main results.

  8. Differential contribution of two peroxisomal protein receptors to the maintenance of peroxisomal functions in Arabidopsis.

    PubMed

    Hayashi, Makoto; Yagi, Mina; Nito, Kazumasa; Kamada, Tomoe; Nishimura, Mikio

    2005-04-15

    Peroxisomes in higher plant cells are known to differentiate in function depending on the cell type. Because of the functional differentiation, plant peroxisomes are subdivided into several classes, such as glyoxysomes and leaf peroxisomes. These peroxisomal functions are maintained by import of newly synthesized proteins containing one of two peroxisomal targeting signals known as PTS1 and PTS2. These targeting signals are known to be recognized by the cytosolic receptors, Pex5p and Pex7p, respectively. To demonstrate the contribution of Pex5p and Pex7p to the maintenance of peroxisomal functions in plants, double-stranded RNA constructs were introduced into the genome of Arabidopsis thaliana. Expression of the PEX5 and PEX7 genes was efficiently reduced by the double-stranded RNA-mediated interference in the transgenic Arabidopsis. The Pex5p-deficient Arabidopsis showed reduced activities for both glyoxysomal and leaf peroxisomal functions. An identical phenotype was observed in a transgenic Arabidopsis overexpressing functionally defective Pex5p. In contrast, the Pex7p-deficient Arabidopsis showed reduced activity for glyoxysomal function but not for leaf peroxisomal function. Analyses of peroxisomal protein import in the transgenic Arabidopsis revealed that Pex5p was involved in import of both PTS1-containing proteins and PTS2-containing proteins, whereas Pex7p contributed to the import of only PTS2-containing proteins. Overall, the results indicated that Pex5p and Pex7p play different roles in the maintenance of glyoxysomal and leaf peroxisomal functions in plants.

  9. Neurobehavioral functioning in obstructive sleep apnea: differential effects of sleep quality, hypoxemia and subjective sleepiness.

    PubMed

    Naismith, S; Winter, V; Gotsopoulos, H; Hickie, I; Cistulli, P

    2004-02-01

    This study evaluated the relationship between neuropsychological and affective functioning, subjective sleepiness and sleep-disordered breathing in 100 patients with obstructive sleep apnea (OSA). Using principal components analysis, three indices of sleep-disordered breathing were identified from polysomnography: sleep disturbance, extent of nocturnal hypoxemia, and sleep quality. Poorer sleep quality was related to slower processing speed, somatic symptomatology and tension-anxiety levels. Nocturnal hypoxemia was related to visuconstructional abilities, processing speed and mental flexibility. Patients who had high levels of subjective sleepiness had poorer performances on a complex task of executive functioning and higher levels of tension-anxiety. These results imply a differential effect of sleep-disordered breathing on domains of neuropsychological functioning. Additionally, they suggest that a patient's subjective level of sleepiness is a good predictor of certain aspects of neurobehavioral functioning.

  10. Identification of differentially methylated loci using wavelet-based functional mixed models

    PubMed Central

    Lee, Wonyul; Morris, Jeffrey S.

    2016-01-01

    Motivation: DNA methylation is a key epigenetic modification that can modulate gene expression. Over the past decade, a lot of studies have focused on profiling DNA methylation and investigating its alterations in complex diseases such as cancer. While early studies were mostly restricted to CpG islands or promoter regions, recent findings indicate that many of important DNA methylation changes can occur in other regions and DNA methylation needs to be examined on a genome-wide scale. In this article, we apply the wavelet-based functional mixed model methodology to analyze the high-throughput methylation data for identifying differentially methylated loci across the genome. Contrary to many commonly-used methods that model probes independently, this framework accommodates spatial correlations across the genome through basis function modeling as well as correlations between samples through functional random effects, which allows it to be applied to many different settings and potentially leads to more power in detection of differential methylation. Results: We applied this framework to three different high-dimensional methylation data sets (CpG Shore data, THREE data and NIH Roadmap Epigenomics data), studied previously in other works. A simulation study based on CpG Shore data suggested that in terms of detection of differentially methylated loci, this modeling approach using wavelets outperforms analogous approaches modeling the loci as independent. For the THREE data, the method suggests newly detected regions of differential methylation, which were not reported in the original study. Availability and implementation: Automated software called WFMM is available at https://biostatistics.mdanderson.org/SoftwareDownload. CpG Shore data is available at http://rafalab.dfci.harvard.edu. NIH Roadmap Epigenomics data is available at http://compbio.mit.edu/roadmap. Supplementary information: Supplementary data are available at Bioinformatics online. Contact: jefmorris

  11. Macaque accessory optic system: II. Connections with the pretectum

    SciTech Connect

    Baleydier, C.; Magnin, M.; Cooper, H.M. )

    1990-12-08

    Connections of the accessory optic system (AOS) with the pretectum are described in the macaque monkey. Injections of tritiated amino acids in the pretectum demonstrate a major contralateral projection to the dorsal (DTN), lateral (LTN), and medial (MTN) terminal nuclei of the AOS and a sparser projection to the ipsilateral LTN. Injections of retrograde tracers, Fast Blue (FB), or wheat germ agglutinin horseradish peroxidase (WGA-HRP) plus nonconjugated horseradish peroxidase (HRP) in the LTN show that the pretectal-LTN projection originates from two nuclei. The main source of pretectal efferents to the LTN is from the pretectal olivary nucleus (OPN) and is entirely contralateral. This projection, which appears unique to primates, originates from the large multipolar cells of the OPN. In addition to this projection, the nucleus of the optic tract (NOT) projects to the ipsilateral LTN, as in nonprimates. Injection of WGA-HRP in the pretectum shows a reciprocal predominantely ipsilateral projection from the LTN to the pretectum. Retinas were observed after injection of FB in the LTN. The retinal ganglion cells projecting to the AOS are mainly distributed near the fovea and in the nasal region of the contralateral eye, suggesting a nasotemporal pattern of decussation. The demonstration of a direct connection between LTN and OPN forces to a reconsideration of the functional role of the AOS. Previous descriptions of luminance responsive cells in the LTN support a possible participation of this nucleus in the control of the pupillary light reflex.

  12. RotundRacGAP Functions with Ras during Spermatogenesis and Retinal Differentiation in Drosophila melanogaster

    PubMed Central

    Bergeret, Evelyne; Pignot-Paintrand, Isabelle; Guichard, Annabel; Raymond, Karine; Fauvarque, Marie-Odile; Cazemajor, Michel; Griffin-Shea, Ruth

    2001-01-01

    Our analysis of rotund (rn) null mutations in Drosophila melanogaster revealed that deletion of the rn locus affects both spermatid and retinal differentiation. In the male reproductive system, the absence of RnRacGAP induced small testes, empty seminal vesicles, short testicular cysts, reduced amounts of interspermatid membrane, the absence of individualization complexes, and incomplete mitochondrial condensation. Flagellar growth continued within the short rn null cysts to produce large bulbous terminations of intertwined mature flagella. Organization of the retina was also severely perturbed as evidenced by grossly misshapen ommatidia containing reduced numbers of photoreceptor and pigment cells. These morphological phenotypes were rescued by genomic rnRacGAP transgenes, demonstrating that RnRacGAP function is critical to spermatid and retinal differentiation. The testicular phenotypes were suppressed by heterozygous hypomorphic mutations in the Dras1 and drk genes, indicating cross talk between RacGAP-regulated signaling and that of the Ras pathway. The observed genetic interactions are consistent with a model in which Rac signaling is activated by Ras and negatively regulated by RnRacGAP during spermatid differentiation. RnRacGAP and Ras cross talk also operated during retinal differentiation; however, while the heterozygous hypomorphic drk mutation continued to act as a suppressor of the rn null mutation, the heterozygous hypomorphic Dras1 mutation induced novel retinal phenotypes. PMID:11509670

  13. Human foreskin fibroblast-like stromal cells can differentiate into functional hepatocytic cells.

    PubMed

    Huang, Hsing-I; Chen, Shao-Kuan; Wang, Robert Y-L; Shen, Chia-Rui; Cheng, Yu-Che

    2013-12-01

    Foreskin fibroblast-like stromal cells (FDSCs) are progenitors isolated from human tissue that can differentiate into diverse cell types. Many types of stem cells can differentiate into hepatocyte-like cells, which could be used for drug testing or in liver regeneration therapy, but whether FDSCs can be converted into functional hepatocytes is unknown. FDSCs show divergent properties when cultured in distinct media, forming spheres in Dulbecco's modified Eagle's medium (DMEM) containing F12, epidermal growth factor (EGF), and basic fibroblast growth factor (b-FGF), but have fibroblast-like morphology when cultured in DMEM-based growth medium. Both cell populations express the typical mesenchymal stem cell markers CD90, CD105, and CD73, but the p75 neurotrophin receptor (p75NTR) was detected only in FDSC spheres. Both types of FDSCs can differentiate into hepatocyte-like cells, which express typical liver markers, including albumin and hepatocyte paraffin 1 (Hep Par1), along with liver-specific biological activities. When plasmids containing the human hepatitis B virus (HBV) genome were transfected transiently into FDSCs, differentiated hepatocyte-like cells secrete large amounts of HBe and HBs antigens. FDSCs could be used for clinical hepatic therapy and/or serve as a model of HBV.

  14. The Core and Accessory Genomes of Burkholderia pseudomallei: Implications for Human Melioidosis

    PubMed Central

    Lin, Chi Ho; Karuturi, R. Krishna M.; Wuthiekanun, Vanaporn; Tuanyok, Apichai; Chua, Hui Hoon; Ong, Catherine; Paramalingam, Sivalingam Suppiah; Tan, Gladys; Tang, Lynn; Lau, Gary; Ooi, Eng Eong; Woods, Donald; Feil, Edward; Peacock, Sharon J.; Tan, Patrick

    2008-01-01

    Natural isolates of Burkholderia pseudomallei (Bp), the causative agent of melioidosis, can exhibit significant ecological flexibility that is likely reflective of a dynamic genome. Using whole-genome Bp microarrays, we examined patterns of gene presence and absence across 94 South East Asian strains isolated from a variety of clinical, environmental, or animal sources. 86% of the Bp K96243 reference genome was common to all the strains representing the Bp “core genome”, comprising genes largely involved in essential functions (eg amino acid metabolism, protein translation). In contrast, 14% of the K96243 genome was variably present across the isolates. This Bp accessory genome encompassed multiple genomic islands (GIs), paralogous genes, and insertions/deletions, including three distinct lipopolysaccharide (LPS)-related gene clusters. Strikingly, strains recovered from cases of human melioidosis clustered on a tree based on accessory gene content, and were significantly more likely to harbor certain GIs compared to animal and environmental isolates. Consistent with the inference that the GIs may contribute to pathogenesis, experimental mutation of BPSS2053, a GI gene, reduced microbial adherence to human epithelial cells. Our results suggest that the Bp accessory genome is likely to play an important role in microbial adaptation and virulence. PMID:18927621

  15. Differential Regulation of Cardiac Function and Intracardiac Cytokines by Rapamycin in Healthy and Diabetic Rats

    PubMed Central

    Luck, Christian; DeMarco, Vincent G.; Mahmood, Abuzar; Gavini, Madhavi P.

    2017-01-01

    Diabetes is comorbid with cardiovascular disease and impaired immunity. Rapamycin improves cardiac functions and extends lifespan by inhibiting the mechanistic target of rapamycin complex 1 (mTORC1). However, in diabetic murine models, Rapamycin elevates hyperglycemia and reduces longevity. Since Rapamycin is an immunosuppressant, we examined whether Rapamycin (750 μg/kg/day) modulates intracardiac cytokines, which affect the cardiac immune response, and cardiac function in male lean (ZL) and diabetic obese Zucker (ZO) rats. Rapamycin suppressed levels of fasting triglycerides, insulin, and uric acid in ZO but increased glucose. Although Rapamycin improved multiple diastolic parameters (E/E′, E′/A′, E/Vp) initially, these improvements were reversed or absent in ZO at the end of treatment, despite suppression of cardiac fibrosis and phosphoSer473Akt. Intracardiac cytokine protein profiling and Ingenuity® Pathway Analysis indicated suppression of intracardiac immune defense in ZO, in response to Rapamycin treatment in both ZO and ZL. Rapamycin increased fibrosis in ZL without increasing phosphoSer473Akt and differentially modulated anti-fibrotic IL-10, IFNγ, and GM-CSF in ZL and ZO. Therefore, fundamental difference in intracardiac host defense between diabetic ZO and healthy ZL, combined with differential regulation of intracardiac cytokines by Rapamycin in ZO and ZL hearts, underlies differential cardiac outcomes of Rapamycin treatment in health and diabetes.

  16. Differing Requirements for MALT1 Function in Peripheral B Cell Survival and Differentiation.

    PubMed

    Lee, Peishan; Zhu, Zilu; Hachmann, Janna; Nojima, Takuya; Kitamura, Daisuke; Salvesen, Guy; Rickert, Robert C

    2017-02-01

    During a T cell-dependent immune response, formation of the germinal center (GC) is essential for the generation of high-affinity plasma cells and memory B cells. The canonical NF-κB pathway has been implicated in the initiation of GC reaction, and defects in this pathway have been linked to immune deficiencies. The paracaspase MALT1 plays an important role in regulating NF-κB activation upon triggering of Ag receptors. Although previous studies have reported that MALT1 deficiency abrogates the GC response, the relative contribution of B cells and T cells to the defective phenotype remains unclear. We used chimeric mouse models to demonstrate that MALT1 function is required in B cells for GC formation. This role is restricted to BCR signaling where MALT1 is critical for B cell proliferation and survival. Moreover, the proapoptotic signal transmitted in the absence of MALT1 is dominant to the prosurvival effects of T cell-derived stimuli. In addition to GC B cell differentiation, MALT1 is required for plasma cell differentiation, but not mitogenic responses. Lastly, we show that ectopic expression of Bcl-2 can partially rescue the GC phenotype in MALT1-deficient animals by prolonging the lifespan of BCR-activated B cells, but plasma cell differentiation and Ab production remain defective. Thus, our data uncover previously unappreciated aspects of MALT1 function in B cells and highlight its importance in humoral immunity.

  17. Peripheral blood monocytes from patients with HBV related decompensated liver cirrhosis can differentiate into functional hepatocytes.

    PubMed

    Yan, Li; Han, Ying; Wang, Jingbo; Liu, Jingmei; Hong, Liu; Fan, Daiming

    2007-11-01

    Peripheral blood monocytes (PBMCs) have the potential to differentiate into various progenitor cells. Here we have investigated the differentiation potential of PBMCs derived from patients with HBV related decompensated liver cirrhosis into hepatocyte-like cells. In our clinical trial, the PBMCs from 2 patients were mobilized by the recombinant human granulocyte colony stimulating factor, followed by leukapheresis and transplantation of PBMCs. PBMCs, induced by recombinant human hepatocyte growth factors, were identified by the expression of hepatocyte markers and specific biological functions with biochemical assays in vitro. Patients showed a lasting clinical amelioration for more than one year after transplantation, and hepatocyte-like cells were identified by expressing liver specific genes, synthesizing albumin, urea, aspirate transaminase, and glycogen, which were all similar to the human normal hepatic cell line QZG. Our results clearly demonstrated that mobilized PBMCs from patients with HBV related decompensated liver cirrhosis could differentiate into functional hepatocyte-like cells, indicating the possibility of autologous cell transplantation for treating patients with HBV related decompensated liver cirrhosis.

  18. Functional evaluation of neural stem cell differentiation by single cell calcium imaging.

    PubMed

    Eiriz, Maria Francisca; Grade, Sofia; Rosa, Alexandra; Xapelli, Sara; Bernardino, Liliana; Agasse, Fabienne; Malva, João O

    2011-09-01

    Neurogenesis in the adult mammalian brain occurs in two specific brain areas, the subventricular zone (SVZ) bordering the lateral ventricles and the subgranular zone (SGZ) of the hippocampus. Although these regions are prone to produce new neurons, cultured cells from these neurogenic niches tend to be mixed cultures, containing both neurons and glial cells. Several reports highlight the potential of the self-healing capacity of the brain following injury. Even though much knowledge has been produced on the neurogenesis itself, brain repairing strategies are still far away from patients cure. Here we review general concepts in the neurogenesis field, also addressing the methods available to study neural stem cell differentiation. A major problem faced by research groups and companies dedicated to brain regenerative medicine resides on the lack of good methods to functionally identify neural stem cell differentiation and novel drug targets. To address this issue, we developed a unique single cell calcium imaging-based method to functionally discriminate different cell types derived from SVZ neural stem cell cultures. The unique functional profile of each SVZ cell type was correlated at the single cell level with the immunodetection of specific phenotypic markers. This platform was raised on the basis of the functional response of neurons, oligodendrocytes and immature cells to depolarising agents, to thrombin and to histamine, respectively. We also outline key studies in which our new platform was extremely relevant in the context of drug discovery and development in the area of brain regenerative medicine.

  19. Rtfc (4931414P19Rik) Regulates in vitro Thyroid Differentiation and in vivo Thyroid Function

    PubMed Central

    Yu, Yang; Liu, Chang; Zhang, Junxia; Zhang, Mimi; Wen, Wei; Ruan, Xianhui; Li, Dapeng; Zhang, Shuang; Gao, Ming; Chen, Lingyi

    2017-01-01

    Thyroid is a one of the most important endocrine organs. Understanding the molecular mechanism underlying thyroid development and function, as well as thyroid diseases, is beneficial for the clinical treatment of thyroid diseases and tumors. Through genetic linkage analysis and exome sequencing, we previously identified an uncharacterized gene C14orf93 (RTFC, mouse homolog: 4931414P19Rik) as a novel susceptibility gene for familial non-medullary thyroid carcinoma, and demonstrated its function in promoting thyroid tumor. However, the role of RTFC in thyroid development and function remains unexplored. In this study, we found that knockout of Rtfc compromises the in vitro thyroid differentiation of mouse embryonic stem cells. In contrast, Rtfc−/− mice are viable and fertile, and the size and the morphology of thyroid are not affected by Rtfc knockout. However, female Rtfc−/− mice, but not male Rtfc−/− mice, display mild hypothyroidism. In summary, our data suggest the roles of Rtfc in in vitro thyroid differentiation of embryonic stem cells, and in vivo thyroid function. PMID:28230092

  20. Impact of Metabolism on T-Cell Differentiation and Function and Cross Talk with Tumor Microenvironment

    PubMed Central

    Kouidhi, Soumaya; Elgaaied, Amel Benammar; Chouaib, Salem

    2017-01-01

    The immune system and metabolism are highly integrated and multilevel interactions between metabolic system and T lymphocyte signaling and fate exist. Accumulating evidence indicates that the regulation of nutrient uptake and utilization in T cells is critically important for the control of their differentiation and manipulating metabolic pathways in these cells can shape their function and survival. This review will discuss some potential cell metabolism pathways involved in shaping T lymphocyte function and differentiation. It will also describe show subsets of T cells have specific metabolic requirements and signaling pathways that contribute to their respective function. Examples showing the apparent similarity between cancer cell metabolism and T cells during activation are illustrated and finally some mechanisms being used by tumor microenvironment to orchestrate T-cell metabolic dysregulation and the subsequent emergence of immune suppression are discussed. We believe that targeting T-cell metabolism may provide an additional opportunity to manipulate T-cell function in the development of novel therapeutics. PMID:28348562

  1. Numerical rate function determination in partial differential equations modeling cell population dynamics.

    PubMed

    Groh, Andreas; Kohr, Holger; Louis, Alfred K

    2017-02-01

    This paper introduces a method to solve the inverse problem of determining an unknown rate function in a partial differential equation (PDE) based on discrete measurements of the modeled quantity. The focus is put on a size-structured population balance equation (PBE) predicting the evolution of the number distribution of a single cell population as a function of the size variable. Since the inverse problem at hand is ill-posed, an adequate regularization scheme is required to avoid amplification of measurement errors in the solution method. The technique developed in this work to determine a rate function in a PBE is based on the approximate inverse method, a pointwise regularization scheme, which employs two key ideas. Firstly, the mollification in the directions of time and size variables are separated. Secondly, instable numerical data derivatives are circumvented by shifting the differentiation to an analytically given function. To examine the performance of the introduced scheme, adapted test scenarios have been designed with different levels of data disturbance simulating the model and measurement errors in practice. The success of the method is substantiated by visualizing the results of these numerical experiments.

  2. Rtfc (4931414P19Rik) Regulates in vitro Thyroid Differentiation and in vivo Thyroid Function.

    PubMed

    Yu, Yang; Liu, Chang; Zhang, Junxia; Zhang, Mimi; Wen, Wei; Ruan, Xianhui; Li, Dapeng; Zhang, Shuang; Gao, Ming; Chen, Lingyi

    2017-02-23

    Thyroid is a one of the most important endocrine organs. Understanding the molecular mechanism underlying thyroid development and function, as well as thyroid diseases, is beneficial for the clinical treatment of thyroid diseases and tumors. Through genetic linkage analysis and exome sequencing, we previously identified an uncharacterized gene C14orf93 (RTFC, mouse homolog: 4931414P19Rik) as a novel susceptibility gene for familial non-medullary thyroid carcinoma, and demonstrated its function in promoting thyroid tumor. However, the role of RTFC in thyroid development and function remains unexplored. In this study, we found that knockout of Rtfc compromises the in vitro thyroid differentiation of mouse embryonic stem cells. In contrast, Rtfc(-/-) mice are viable and fertile, and the size and the morphology of thyroid are not affected by Rtfc knockout. However, female Rtfc(-/-) mice, but not male Rtfc(-/-) mice, display mild hypothyroidism. In summary, our data suggest the roles of Rtfc in in vitro thyroid differentiation of embryonic stem cells, and in vivo thyroid function.

  3. Multivoxel patterns reveal functionally differentiated networks underlying auditory feedback processing of speech.

    PubMed

    Zheng, Zane Z; Vicente-Grabovetsky, Alejandro; MacDonald, Ewen N; Munhall, Kevin G; Cusack, Rhodri; Johnsrude, Ingrid S

    2013-03-06

    The everyday act of speaking involves the complex processes of speech motor control. An important component of control is monitoring, detection, and processing of errors when auditory feedback does not correspond to the intended motor gesture. Here we show, using fMRI and converging operations within a multivoxel pattern analysis framework, that this sensorimotor process is supported by functionally differentiated brain networks. During scanning, a real-time speech-tracking system was used to deliver two acoustically different types of distorted auditory feedback or unaltered feedback while human participants were vocalizing monosyllabic words, and to present the same auditory stimuli while participants were passively listening. Whole-brain analysis of neural-pattern similarity revealed three functional networks that were differentially sensitive to distorted auditory feedback during vocalization, compared with during passive listening. One network of regions appears to encode an "error signal" regardless of acoustic features of the error: this network, including right angular gyrus, right supplementary motor area, and bilateral cerebellum, yielded consistent neural patterns across acoustically different, distorted feedback types, only during articulation (not during passive listening). In contrast, a frontotemporal network appears sensitive to the speech features of auditory stimuli during passive listening; this preference for speech features was diminished when the same stimuli were presented as auditory concomitants of vocalization. A third network, showing a distinct functional pattern from the other two, appears to capture aspects of both neural response profiles. Together, our findings suggest that auditory feedback processing during speech motor control may rely on multiple, interactive, functionally differentiated neural systems.

  4. Detection and differentiation of influenza viruses with glycan-functionalized gold nanoparticles.

    PubMed

    Zheng, Longtang; Wei, Jinhua; Lv, Xun; Bi, Yuhai; Wu, Peixing; Zhang, Zhenxing; Wang, Pengfei; Liu, Ruichen; Jiang, Jingwen; Cong, Haolong; Liang, Jingnan; Chen, Wenwen; Cao, Hongzhi; Liu, Wenjun; Gao, George F; Du, Yuguang; Jiang, Xingyu; Li, Xuebing

    2017-05-15

    Accurate diagnosis of influenza viruses is difficult and generally requires a complex process because of viral diversity and rapid mutability. In this study, we report a simple and rapid strategy for the detection and differentiation of influenza viruses using glycan-functionalized gold nanoparticles (gGNPs). This method is based on the aggregation of gGNP probes on the viral surface, which is mediated by the specific binding of the virus to the glycans. Using a set of gGNPs bearing different glycan structures, fourteen influenza virus strains, including the major subtypes currently circulating in human and avian populations, were readily differentiated from each other and from a human respiratory syncytial virus in a single-step colorimetric procedure. The results presented here demonstrate the potential of this gGNP-based system in the development of convenient and portable sensors for the clinical diagnosis and surveillance of influenza viruses.

  5. Tissue-specific DNA demethylation is required for proper B-cell differentiation and function

    PubMed Central

    Orlanski, Shari; Labi, Verena; Reizel, Yitzhak; Spiro, Adam; Lichtenstein, Michal; Levin-Klein, Rena; Koralov, Sergei B.; Skversky, Yael; Rajewsky, Klaus; Cedar, Howard; Bergman, Yehudit

    2016-01-01

    There is ample evidence that somatic cell differentiation during development is accompanied by extensive DNA demethylation of specific sites that vary between cell types. Although the mechanism of this process has not yet been elucidated, it is likely to involve the conversion of 5mC to 5hmC by Tet enzymes. We show that a Tet2/Tet3 conditional knockout at early stages of B-cell development largely prevents lineage-specific programmed demethylation events. This lack of demethylation affects the expression of nearby B-cell lineage genes by impairing enhancer activity, thus causing defects in B-cell differentiation and function. Thus, tissue-specific DNA demethylation appears to be necessary for proper somatic cell development in vivo. PMID:27091986

  6. Electrical double layers and differential capacitance in molten salts from density functional theory

    DOE PAGES

    Frischknecht, Amalie L.; Halligan, Deaglan O.; Parks, Michael L.

    2014-08-05

    Classical density functional theory (DFT) is used to calculate the structure of the electrical double layer and the differential capacitance of model molten salts. The DFT is shown to give good qualitative agreement with Monte Carlo simulations in the molten salt regime. The DFT is then applied to three common molten salts, KCl, LiCl, and LiKCl, modeled as charged hard spheres near a planar charged surface. The DFT predicts strong layering of the ions near the surface, with the oscillatory density profiles extending to larger distances for larger electrostatic interactions resulting from either lower temperature or lower dielectric constant. Inmore » conclusion, overall the differential capacitance is found to be bell-shaped, in agreement with recent theories and simulations for ionic liquids and molten salts, but contrary to the results of the classical Gouy-Chapman theory.« less

  7. Electrical double layers and differential capacitance in molten salts from density functional theory

    SciTech Connect

    Frischknecht, Amalie L.; Halligan, Deaglan O.; Parks, Michael L.

    2014-08-05

    Classical density functional theory (DFT) is used to calculate the structure of the electrical double layer and the differential capacitance of model molten salts. The DFT is shown to give good qualitative agreement with Monte Carlo simulations in the molten salt regime. The DFT is then applied to three common molten salts, KCl, LiCl, and LiKCl, modeled as charged hard spheres near a planar charged surface. The DFT predicts strong layering of the ions near the surface, with the oscillatory density profiles extending to larger distances for larger electrostatic interactions resulting from either lower temperature or lower dielectric constant. In conclusion, overall the differential capacitance is found to be bell-shaped, in agreement with recent theories and simulations for ionic liquids and molten salts, but contrary to the results of the classical Gouy-Chapman theory.

  8. Effect of RGD-functionalization and stiffness modulation of polyelectrolyte multilayer films on muscle cell differentiation

    PubMed Central

    Gribova, Varvara; Gauthier-Rouvière, Cécile; Albigès-Rizo, Corinne; Auzely-Velty, Rachel; Picart, Catherine

    2014-01-01

    Skeletal muscle tissue engineering holds promise for the replacement of muscle due to an injury and for the treatment of muscle diseases. Although RGD substrates have been widely explored in tissue engineering, there is no study aimed at investigating the combined effects of RGD nanoscale presentation and matrix stiffness on myogenesis. In the present work, we use polyelectrolyte multilayer films made of poly(L-lysine) (PLL) and poly(L-glutamic) acid (PGA) as substrates of tunable stiffness that can be functionalized by a RGD adhesive peptide to investigate important events in myogenesis, including adhesion, migration, proliferation and differentiation. C2C12 myoblasts were used as cellular models. RGD presentation on soft films and increased film stiffness could both induce cell adhesion, but integrins involved in adhesion were different in case of soft and stiff films. Moreover, soft films with RGD peptide appeared to be the most appropriate substrate for myogenic differentiation while the stiff PLL/PGA films significantly induced cell migration, proliferation and inhibited myogenic differentiation. The ROCK kinase was found to be involved in myoblast response to the different films. Indeed, its inhibition was sufficient to rescue the differentiation on stiff films, but no significant changes were observed on stiff films with the RGD peptide. These results suggest that different signaling pathways may be activated depending on mechanical and biochemical properties of the multilayer films. This study emphasizes the superior advantage of the soft PLL/PGA films presenting the RGD peptide in terms of myogenic differentiation. This soft RGD-presenting film may be further used as coating of various polymeric scaffolds for muscle tissue engineering. PMID:23261924

  9. Effect of lamin A/C knockdown on osteoblast differentiation and function.

    PubMed

    Akter, Rahima; Rivas, Daniel; Geneau, Graziello; Drissi, Hicham; Duque, Gustavo

    2009-02-01

    Recent studies have associated mutations in lamin A/C, a component of the nuclear lamina, with premature aging and severe bone loss. In this study, we hypothesized that reduced expression of lamin A/C has a negative impact on osteoblastogenesis and bone formation in vitro. We inhibited lamin A/C using increasing doses of lamin A/C siRNA in normal human osteoblasts and differentiating mesenchymal stem cells (MSCs). Untreated cells and cells treated with vehicle but without the siRNA-oligo were used as control. The level of effectiveness of siRNA was determined by RT-PCR, Western blot, and immunofluorescence. Nuclear blebbing, a typical finding of lamin A/C inhibition, was quantified using propidium iodine staining, and its effect on cell survival was determined using MTS-formazan. Furthermore, alizarin red and alkaline phosphatase staining were correlated with osteocalcin secretion and levels of expression of osteocalcin, osterix, bone sialoprotein, and Runx2. Finally, the nuclear binding activity of Runx2, an essential transcription factor for osteoblast differentiation, was assessed using ELISA and EMSA. A successful inhibitory effect on the lamin A/C gene at doses of 400-800 nM oligo was obtained without affecting cell survival. Whereas osteoblast function was significantly affected by lamin A/C inhibition, siRNA-treated MSC showed a higher incidence of nuclear changes, lower osteoblast differentiation, and enhanced adipocyte differentiation. Finally, lamin A/C knockdown reduced Runx2 nuclear binding activity without affecting Runx2 expression. In summary, our results indicate that lamin A/C is a new factor needed for osteoblast differentiation that plays an important role in the cellular mechanisms of age-related bone loss.

  10. CD4 CTL, a Cytotoxic Subset of CD4+ T Cells, Their Differentiation and Function

    PubMed Central

    Takeuchi, Arata; Saito, Takashi

    2017-01-01

    CD4+ T cells with cytotoxic activity (CD4 CTL) have been observed in various immune responses. These cells are characterized by their ability to secrete granzyme B and perforin and to kill the target cells in an MHC class II-restricted fashion. Although CD4 CTLs were once thought to be an in vitro artifact associated with long-term culturing, they have since been identified in vivo and shown to play important roles in antiviral and antitumor immunity, as well as in inflammation. Functional characterization of CD4 CTL suggests their potential significance for therapeutic purposes. However, in order to develop effective CD4 CTL therapy it is necessary to understand the differentiation and generation of these cells. Although the mechanisms regulating development of various CD4+ Th subsets have been clarified in terms of the cytokine and transcription factor requirement, the CD4 CTL differentiation mechanism remains elusive. These cells are thought to be most closely related to Th1 cells secreting IFNγ and regulated by eomesodermin and/or T-bet transcription factors for their differentiation. However, our studies and those of others have identified CD4 CTLs within other CD4+ T cell subsets, including naïve T cells. We have identified class I-restricted T cell-associated molecule as a marker of CD4 CTL and, by using this marker, we detected a subset of naïve T cells that have the potential to differentiate into CD4 CTL. CD4 CTL develops at sites of infections as well as inflammation. In this review, we summarize recent findings about the generation of CD4 CTL and propose a model with several differentiation pathways. PMID:28280496

  11. Differentiating the stem cell pool of human hair follicle outer root sheath into functional melanocytes.

    PubMed

    Schneider, Marie; Dieckmann, Christina; Rabe, Katrin; Simon, Jan-Christoph; Savkovic, Vuk

    2014-01-01

    Bench-to-Bedside concepts for regenerative therapy place significant weight on noninvasive approaches, with harvesting of the starting material as a header. This is particularly important in autologous treatments, which use one's bodily constituents for therapy. Precisely the stretch between obtaining therapeutic elements invasively and noninvasively places non-intrusive "sampling" rather than "biopsy" in the center of the road map of developing an autologous regenerative therapy. We focus on such a noninvasively available source of adult stem cells that we carry with us throughout our life, available at our fingertips-or shall we say hair roots, by a simple plucking of hair: the human hair follicle. This chapter describes an explant procedure for cultivating melanocytes differentiated from the stem cell pool of the hair follicle Outer Root Sheath (ORS). In vivo, the most abundant derivatives of the heterogeneous ORS stem cell pool are epidermal cells-melanocytes and keratinocytes which complete their differentiation-either spontaneously or upon picking up regenerative cues from damaged skin-and migrate from the ORS towards the adjacent regenerating area of the epidermis. We have taken advantage of the ORS developmental potential by optimizing explant primary culture, expansion and melanogenic differentiation of resident ORS stem cells towards end-stage melanocytes in order to obtain functional melanocytes noninvasively for the purposes of transplantation and use them for the treatment of depigmentation disorders. Our protocol specifies sampling of hair with their ORS, follicle medium-air interface primary culture, stimulation of cell outgrowth, adherent culture and differentiation of ORS stem cells and precursors towards fully functional melanocytes. Along with cultivation, we describe selection techniques for establishing and maintaining a pure melanocyte population and methods suitable for determining melanocyte identity.

  12. Accessory costs of seed production and the evolution of angiosperms.

    PubMed

    Lord, Janice M; Westoby, Mark

    2012-01-01

    Accessory costs of reproduction frequently equal or exceed direct investment in offspring, and can limit the evolution of small offspring sizes. Early angiosperms had minimum seed sizes, an order of magnitude smaller than their contemporaries. It has been proposed that changes to reproductive features at the base of the angiosperm clade reduced accessory costs thus removing the fitness disadvantage of small seeds. We measured accessory costs of reproduction in 25 extant gymnosperms and angiosperms, to test whether angiosperms can produce small seeds more economically than gymnosperms. Total accessory costs scaled isometrically to seed mass for angiosperms but less than isometrically for gymnosperms, so that smaller seeds were proportionally more expensive for gymnosperms to produce. In particular, costs of abortions and packaging structures were significantly higher in gymnosperms. Also, the relationship between seed:ovule ratio and seed size was negative in angiosperms but positive in gymnosperms. We argue that the carpel was a key evolutionary innovation reducing accessory costs in angiosperms by allowing sporophytic control of pre- and postzygotic mate selection and timing of resource allocation. The resulting reduction in costs of aborting unfertilized ovules or genetically inferior embryos would have lowered total reproductive costs enabling early angiosperms to evolve small seed sizes and short generation times.

  13. Amphibian gut microbiota shifts differentially in community structure but converges on habitat-specific predicted functions

    PubMed Central

    Bletz, Molly C.; Goedbloed, Daniel J.; Sanchez, Eugenia; Reinhardt, Timm; Tebbe, Christoph C.; Bhuju, Sabin; Geffers, Robert; Jarek, Michael; Vences, Miguel; Steinfartz, Sebastian

    2016-01-01

    Complex microbial communities inhabit vertebrate digestive systems but thorough understanding of the ecological dynamics and functions of host-associated microbiota within natural habitats is limited. We investigate the role of environmental conditions in shaping gut and skin microbiota under natural conditions by performing a field survey and reciprocal transfer experiments with salamander larvae inhabiting two distinct habitats (ponds and streams). We show that gut and skin microbiota are habitat-specific, demonstrating environmental factors mediate community structure. Reciprocal transfer reveals that gut microbiota, but not skin microbiota, responds differentially to environmental change. Stream-to-pond larvae shift their gut microbiota to that of pond-to-pond larvae, whereas pond-to-stream larvae change to a community structure distinct from both habitat controls. Predicted functions, however, match that of larvae from the destination habitats in both cases. Thus, microbial function can be matched without taxonomic coherence and gut microbiota appears to exhibit metagenomic plasticity. PMID:27976718

  14. Differential effects of hunger and satiety on insular cortex and hypothalamic functional connectivity.

    PubMed

    Wright, Hazel; Li, Xiaoyun; Fallon, Nicholas B; Crookall, Rebecca; Giesbrecht, Timo; Thomas, Anna; Halford, Jason C G; Harrold, Joanne; Stancak, Andrej

    2016-05-01

    The insula cortex and hypothalamus are implicated in eating behaviour, and contain receptor sites for peptides and hormones controlling energy balance. The insula encompasses multi-functional subregions, which display differential anatomical and functional connectivities with the rest of the brain. This study aimed to analyse the effect of fasting and satiation on the functional connectivity profiles of left and right anterior, middle, and posterior insula, and left and right hypothalamus. It was hypothesized that the profiles would be altered alongside changes in homeostatic energy balance. Nineteen healthy participants underwent two 7-min resting state functional magnetic resonance imaging scans, one when fasted and one when satiated. Functional connectivity between the left posterior insula and cerebellum/superior frontal gyrus, and between left hypothalamus and inferior frontal gyrus was stronger during fasting. Functional connectivity between the right middle insula and default mode structures (left and right posterior parietal cortex, cingulate cortex), and between right hypothalamus and superior parietal cortex was stronger during satiation. Differences in blood glucose levels between the scans accounted for several of the altered functional connectivities. The insula and hypothalamus appear to form a homeostatic energy balance network related to cognitive control of eating; prompting eating and preventing overeating when energy is depleted, and ending feeding or transferring attention away from food upon satiation. This study provides evidence of a lateralized dissociation of neural responses to energy modulations.

  15. Highly efficient differentiation of hESCs to functional hepatic endoderm requires ActivinA and Wnt3a signaling

    PubMed Central

    Hay, David C.; Fletcher, Judy; Payne, Catherine; Terrace, John D.; Gallagher, Ronald C. J.; Snoeys, Jan; Black, James R.; Wojtacha, Davina; Samuel, Kay; Hannoun, Zara; Pryde, Anne; Filippi, Celine; Currie, Ian S.; Forbes, Stuart J.; Ross, James A.; Newsome, Philip N.; Iredale, John P.

    2008-01-01

    Human embryonic stem cells (hESCs) are a valuable source of pluripotential primary cells. To date, however, their homogeneous cellular differentiation to specific cell types in vitro has proven difficult. Wnt signaling has been shown to play important roles in coordinating development, and we demonstrate that Wnt3a is differentially expressed at critical stages of human liver development in vivo. The essential role of Wnt3a in hepatocyte differentiation from hESCs is paralleled by our in vitro model, demonstrating the importance of a physiologic approach to cellular differentiation. Our studies provide compelling evidence that Wnt3a signaling is important for coordinated hepatocellular function in vitro and in vivo. In addition, we demonstrate that Wnt3a facilitates clonal plating of hESCs exhibiting functional hepatic differentiation. These studies represent an important step toward the use of hESC-derived hepatocytes in high-throughput metabolic analysis of human liver function. PMID:18719101

  16. Solutions to an advanced functional partial differential equation of the pantograph type.

    PubMed

    Zaidi, Ali A; Van Brunt, B; Wake, G C

    2015-07-08

    A model for cells structured by size undergoing growth and division leads to an initial boundary value problem that involves a first-order linear partial differential equation with a functional term. Here, size can be interpreted as DNA content or mass. It has been observed experimentally and shown analytically that solutions for arbitrary initial cell distributions are asymptotic as time goes to infinity to a certain solution called the steady size distribution. The full solution to the problem for arbitrary initial distributions, however, is elusive owing to the presence of the functional term and the paucity of solution techniques for such problems. In this paper, we derive a solution to the problem for arbitrary initial cell distributions. The method employed exploits the hyperbolic character of the underlying differential operator, and the advanced nature of the functional argument to reduce the problem to a sequence of simple Cauchy problems. The existence of solutions for arbitrary initial distributions is established along with uniqueness. The asymptotic relationship with the steady size distribution is established, and because the solution is known explicitly, higher-order terms in the asymptotics can be readily obtained.

  17. Importance of renal depth correction for quantitation of differential renal function

    SciTech Connect

    Choi, H.; Kirchner, P.T.

    1985-05-01

    To assess the frequency and magnitude of errors caused by asymmetries in renal depth, when estimates of differential function are based only posterior projections (as in DTPA studies). The authors compared ratios of right-to-left (R/L) DMSA localization derived from posterior camera images with R/L ratios based on geometric mean of posterior and anterior counts of each kidney. The factor (X) required to convert the ratio of R/L posterior counts to the more accurate R/L geometric counts (Rp/Lp.X = Rg/Lg) was determined in 55 randomly selected patients referred for DMSA studies. Frequency distributions for X and l/X reveal that the use of posterior counts alone is likely to produce differential flow/function estimates with errors greater than 30% in 5% of patients, greater than 20% in 16 of patients. Lack of depth correction also widens the normal range derived from normal controls, thus reducing sensitivity and specificity of quantitative renal studies by two different mechanisms. The authors recommend routine application of depth correction by conjugate counting or ultrasound techniques for all quantitations of renal function.

  18. Existence, uniqueness, and stability of stochastic neutral functional differential equations of Sobolev-type

    SciTech Connect

    Yang, Xuetao; Zhu, Quanxin

    2015-12-15

    In this paper, we are mainly concerned with a class of stochastic neutral functional differential equations of Sobolev-type with Poisson jumps. Under two different sets of conditions, we establish the existence of the mild solution by applying the Leray-Schauder alternative theory and the Sadakovskii’s fixed point theorem, respectively. Furthermore, we use the Bihari’s inequality to prove the Osgood type uniqueness. Also, the mean square exponential stability is investigated by applying the Gronwall inequality. Finally, two examples are given to illustrate the theory results.

  19. Discontinuous initial value problems for functional differential-algebraic equations of mixed type

    NASA Astrophysics Data System (ADS)

    d'Albis, H.; Augeraud-Véron, E.; Hupkes, H. J.

    We study the well-posedness of initial value problems for nonlinear functional differential-algebraic equations of mixed type. We are interested in solutions to such problems that admit a single jump discontinuity at time zero. We focus specially on the question whether unstable equilibria can be stabilized by appropriately choosing the size of the jump discontinuity. We illustrate our techniques by analytically studying an economic model for the interplay between inflation and interest rates. In particular, we investigate under which circumstances the central bank can prevent runaway inflation by appropriately hiking the interest rate.

  20. Case report: accessory head of the deep forearm flexors

    PubMed Central

    JONES, M.; ABRAHAMS, P. H.; SAÑUDO, J. R.

    1997-01-01

    In 1813 Gantzer described 2 accessory muscles in the human forearm which bear his name (Wood, 1868; Macalister, 1875) and these have subsequently been reported with variable attachments (Wood, 1868; Macalister, 1875; Turner, 1879; Schäfer & Thane, 1894; Le Double, 1897; Dykes & Anson, 1944; Mangini, 1960; Malhotra et al. 1982; Kida, 1988; Tountas & Bergman, 1993). The accessory heads of the deep flexors of the forearm (Gantzer's muscles) have been described as 2 different small bellies which insert either into FPL or FDP. There are no previous reports which have mentioned the existence of an accessory muscle which inserts into both of the 2 deep flexors of the forearm as in the case presented here. PMID:9306208